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Bar chart

A bar chart or bar graph is a chart or graph that presents categorical data with rectangular bars with heights or lengths proportional to the values that they represent. The bars can be plotted vertically or horizontally. A vertical bar chart is sometimes called a column chart.

A bar graph shows comparisons among discrete categories. One axis of the chart shows the specific categories being compared, and the other axis represents a measured value. Some bar graphs present bars clustered in groups of more than one, showing the values of more than one measured variable.

History
Many sources consider William Playfair (1759-1824) to have invented the bar chart and the Exports and Imports of Scotland to and from different parts for one Year from Christmas 1780 to Christmas 1781 graph from his The Commercial and Political Atlas to be the first bar chart in history. Diagrams of the velocity of a constantly accelerating object against time published in The Latitude of Forms (attributed to Jacobus de Sancto Martino or, perhaps, to Nicole Oresme) about 300 years before can be interpreted as "proto bar charts".

Usage
Bar graphs/charts provide a visual presentation of categorical data. Categorical data is a grouping of data into discrete groups, such as months of the year, age group, shoe sizes, and animals. These categories are usually qualitative. In a column (vertical) bar chart, categories appear along the horizontal axis and the height of the bar corresponds to the value of each category.

Bar charts have a discrete domain of categories, and are usually scaled so that all the data can fit on the chart. When there is no natural ordering of the categories being compared, bars on the chart may be arranged in any order. Bar charts arranged from highest to lowest incidence are called Pareto charts.

Grouped (clustered) and stacked
Bar graphs can also be used for more complex comparisons of data with grouped (or "clustered") bar charts, and stacked bar charts.

In grouped (clustered) bar charts, for each categorical group there are two or more bars color-coded to represent a particular grouping. For example, a business owner with two stores might make a grouped bar chart with different colored bars to represent each store: the horizontal axis would show the months of the year and the vertical axis would show revenue.

Alternatively, Stacked bar charts (also known as Composite bar charts) stack bars on top of each other so that the height of the resulting stack shows the combined result. Unlike a grouped bar chart where each factor is displayed next to another, each with their own bar, the stacked bar chart displays multiple data points stacked in a single row or column. This may, for instance, take the form of uniform height bars charting a time series with internal stacked colours indicating the percentage participation of a sub-type of data. Another example would be a time series displaying total numbers, with internal colors indicating participation in the total by sub-types. Stacked bar charts are not suited to data sets having both positive and negative values.

Grouped bar charts usually present the information in the same order in each grouping. Stacked bar charts present the information in the same sequence on each bar.

Variable-width (variwide)

Variable-width bar charts, sometimes abbreviated variwide (bar) charts, are bar charts having bars with non-uniform widths. Generally:
 * Bars represent quantities with respective rectangles of areas A that are respective arithmetic products of related pairs of
 * — vertical-axis quantities (A/X) and
 * — horizontal-axis quantities (X).

 * Arithmetically, the area of each bar (rectangle) is determined a product of sides' lengths:
 *  = Area A for each bar

Roles of the vertical and horizontal axes may be reversed, depending on the desired application.

Examples of variable-width bar charts are shown at Wikimedia Commons.

Advantages

 * 1) Easy to read and interpret: Bar charts are easy to read and interpret, even for people without a background in statistics or data visualization. The bars make it easy to compare values and see trends, making it a useful tool for communicating information to a wide range of audiences.
 * 2) Can handle large amounts of data: Bar charts can handle large amounts of data and still provide a clear representation of the information. The bars can be made narrow or wide to fit a large number of categories or data points, and the use of color or patterns can make it easier to distinguish between them.
 * 3) Customizable: Bar charts can be customized to suit the needs of the user. For example, the color, width, and height of the bars can be adjusted to make the chart more visually appealing, and labels and annotations can be added to provide additional information.
 * 4) Useful for comparing values: Bar charts are particularly useful for comparing values between categories or data points. They allow for quick identification of differences and similarities, making it easy to draw conclusions and make decisions.

Limitations

 * 1) Limited use for continuous data: Bar charts are not useful for displaying continuous data, such as temperature or time. For continuous data, a line chart or scatter plot may be more appropriate. Bar charts of continuous data with error bars are sometimes referred to as dynamite plots.
 * 2) Limited use for small sample sizes: Bar charts may not be useful for displaying small sample sizes, as the bars may not accurately represent the data. In such cases, a histogram or box plot may be more appropriate.
 * 3) May be misleading: Bar charts can be misleading if the scale is not appropriate or if the data is presented in a way that is designed to mislead the viewer. For example, if the y-axis is truncated, the differences between the bars may appear larger than they actually are.
 * 4) Limited scope for multivariate data: Bar charts can only display one or two variables at a time, making them less useful for displaying multivariate data. In such cases, a scatter plot or heat map may be more appropriate.

title: Bar chart


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User:Sureshan

Hi I'm Sureshan here, from Kasaragod, Kerala. Currently from Munich, Germany

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: User:Sureshan


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Gwangyang

Gwangyang is a city in South Jeolla Province, South Korea. Gwangyang city is the home of POSCO's Gwangyang Steel Works, the largest facility of its kind in the world. The city is also home to K League Classic football side Jeonnam Dragons.

Gwangyang is at the centre of development for the Gwangyang Bay Area Free Economic Zone (GFEZ), the third-largest among the six free economic zones of South Korea, covering 92.7 square kilometers. The Free Economic Zone focus on port container handling, steel production, shipbuilding as well as leisure facilities. The area has become a mega business hub, exploiting its accessibility to China.

Famous people from Gwangyang include National Intelligence Service head Kim Seung-kew. To the north of the city is the county of Gurye, to the east along the Seomjin River is the county of Hadong in Gyeongsangnam-do, and to the south is the Gwangyang Bay. Mountains in the city include Baegunsan (백운산, 1,217m), to the south is Gayasan (가야산, 497m) and Gubonghwasan (구봉화산, 473m). Baegunsan is the second-highest mountain in Jeollanam-do with the exception of Jirisan (지리산, 1,915 m).

The average yearly temperature is 13.7 °C, the average in January is 0.1 °C, and the average in July is 27.8 °C. The average yearly precipitation is 1296 mm

As of October 14, 2007, plans are being set up and a referendum is being planned for a merging of the cities of Yeosu, Suncheon and Gwangyang into a new metropolitan city, taking advantage of the Gwangyang Bay Free Economic Zone, Yeosu's Expo 2012 bid and port facilities, Suncheon's educational institutes and Gwangyang's POSCO plant.

Symbols

 * Tree : Gorosoe
 * Bird : Sea gull
 * Flower : Camellia

Gwangyang Steel Works
The Steel Works in Gwangyang is POSCO's second mill in the country after the mill in Pohang. The mill boasts having the largest steel plant in the world, the most modern technology, and the best facilities for steel manufacturing. It presently produces coil used for making bridges, iron structures, cars, refrigerators, and more. Its production capacity averages about 18 million tons per year. This plant is also a tourist destination for many people, attracting more than 300,000 people from around the globe.

Location
Gwangyang is a strategically important city situated in the southern center of the Korean peninsula. For these geopolitical reasons, Gwangyang is a city which functions as an axis for the balanced development of the country covering South Jeolla area with western parts of Mokpo and Muan.

Places of interest
Gwangyang is home to many unique natural and cultural sites as well as many different festivals during the four seasons. Points of interest include: The festivals include:
 * The Baegun mountains
 * Maehwa Village
 * Yudang Park
 * The Natural Resort Park
 * Gwangyang Cultural Center
 * The Baegun Mountain Medicinal Water Festival
 * The Maehwa Culture Festival
 * The Jeoneo Fish Festival

Festival
Gwangyang is famous for its beautiful apricot trees. In Korean, Ume flower is called maehwa(매화) and it has been honored for its early blooming. Because of its characteristic, the Gwangyang Maehwa Festival is the earliest opened festival in the whole South Jeolla Province area.

Other festivals in Gwangyang are the Baegunsan Mountain Gorosoe Festival, Seomjingang Culture Festival and the Gwangyang Sutbulgui Festival.

Twin towns – Sister cities
Gwangyang is twinned with:

title: Gwangyang


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Severn (disambiguation)

Severn most commonly refers to the River Severn, the longest in the United Kingdom.

Severn may also refer to:

Australia

 * Severn River (New South Wales)
 * Severn River (Queensland)

Canada

 * Severn River (central Ontario)
 * Severn River (northern Ontario)

New Zealand

 * Severn River (New Zealand)

United Kingdom

 * River Severn, the longest river in the United Kingdom
 * Severn Estuary, the estuary of that river
 * Bristol Channel, also known as the Severn Sea, the stretch of water to the west of the estuary
 * River Seven, a river in North Yorkshire, England

United States

 * Severn River (Maryland)
 * Severn River (Virginia)

Canada

 * Severn, Ontario and Port Severn
 * Fort Severn, a Hudson's Bay Company post at the mouth of the Severn River in northern Ontario
 * Fort Severn Airport, Ontario, Canada
 * Fort Severn First Nation, the northernmost community in Ontario
 * Severn Bridge, Ontario, Canada

United Kingdom

 * Severn Beach, South Gloucestershire, England
 * Severn (Caldicot ward), an electoral ward in Monmouthshire, Wales
 * Severn Stoke

United States

 * Severn, Maryland, a census-designated place
 * Severn, North Carolina, a town
 * Fort Severn, one of the three original military bases that now make up the United States Naval Academy

People with the given name

 * Severn Cullis-Suzuki (born 1979), environmental activist, speaker, television host and author
 * Severn Darden (1929–1995), American comedian
 * Severn Teackle Wallis (1816–1894), American lawyer

People with the surname

 * Christopher Severn (born 1935), American former screen actor
 * Claud Severn (1869–1933), British colonial governor of Hong Kong, son of Walter Severn
 * Cliff Severn (1925-2014), American cricketer and child screen actor
 * Dan Severn (born 1958), American martial artist and professional wrestler
 * Edmund Severn (1862–1942), American violinist and composer
 * Ernest Severn (1933-1987), American child screen actor
 * James Severn (born 1991), English association footballer
 * Joseph Severn (1793–1879), English portrait and subject painter
 * Raymond Severn (1930-1994), American cricketer and child screen actor
 * Walter Severn (1830–1904), English watercolour artist, son of Joseph Severn
 * William Severn (1938-1983), American child screen actor
 * Winston Severn (born 1942), American former cricketer and child screen actor
 * Yvonne Severn (1927-2006), American child screen actress

People with the title

 * Prince Edward, Duke of Edinburgh (born 1964) has the title Viscount Severn as one of his subsidiary titles.

Arts, entertainment, and media

 * Severn Sound, a UK Independent Local Radio station that broadcast throughout Gloucestershire
 * Severn Valley (Cthulhu Mythos), a fictional setting in the writings of Ramsey Campbell
 * The Severn (radio), a radio station serving Shrewsbury and Oswestry, England

Ships

 * HMS Severn, the name of nine ships and one submarine of the Royal Navy
 * Severn-class lifeboat, the largest class of lifeboat used by the RNLI
 * SS Severn River
 * USS Severn (1867), a ship from the American Civil War

Other uses

 * Severn, a codename of an early beta version of the Fedora operating system, then known as Red Hat Linux 9.0.93
 * Severn School, an independent preparatory school in Severna Park, Maryland

title: Severn (disambiguation)


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Talk:Public-key cryptography

External links modified (January 2018)
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Trim and tidy
Have just done a tidy-up of the intro. The rest of the article is in dire need of the same. - Snori (talk) 19:14, 26 December 2018 (UTC)
 * Have now done a fairly brutal edit of the body. I would suggest that the most important element to any further changes are: Keeping/building a good structure of sections; Tight wording; Good citations to back the text. - Snori (talk) 20:35, 26 December 2018 (UTC)

I believe the introduction needs another clarification. imo it confuses the objective (mathematical) fact that asymmetric cryptography allows for two unrelated keys to encrypt and decrypt any string / message with the convention that one of those keys is considered public and the other private for most uses. Your comments welcome.--BBird (talk) 13:47, 7 August 2019 (UTC)
 * You’re absolutely right about the confusion of the two objective facts in the lead, but the problems with this article go further than that. I came to it hoping to find an explanation about how it is that one key (namely, the private key) can decrypt something that was encrypted using another key (namely, the public one), but there is nothing in the entire article that explains this.

 * The principle seems to imply that the two keys are related, but... how, exactly? In fact, the first bullet of the Description section does (somewhat) confirm a relation by stating that the private key must “match” the public one that was used for the encryption. Again: how exactly do they match? 74.58.147.69 (talk) 20:17, 27 August 2019 (UTC)

Reverted vandalism
I have just reverted a spate of changes by @2402:3a80:19f8:c3dc::2 which had seemingly randomly copy-pasted chunks of text of the article into different sections. As far as I can tell there were no meaningful contributions made with any of these edits – just nuisance text. I think I got them all. Phidica (talk) 02:17, 9 December 2022 (UTC)

 * @Phidica It looks like you got it all. I wasn't sure what was going on with this contribution. Thanks for evaluating it. ~Kvng (talk) 15:24, 12 December 2022 (UTC)

Diffie Hellman Diagram
Is the Diffie Hellman Diagram accurate? Im under the impression that the shared secret is obtained by a shared public secret combined with the two private keys. The diagram seems to indicate that the private key of Alice with the public key of Bob is equal to the private key of Bob mixed with the public key of Alice. Epachamo (talk) 23:48, 9 February 2024 (UTC)

 * Yes, it is accurate. Alice and Bob's private keys are $$a$$ and $$b$$, and their public keys are $$g^a$$ and $$g^b$$.  Alice computes the shared secret by combining her private key $$a$$ with Bob's public key $$g^b$$ via $$(g^b)^a = g^{ba} = g^{ab}$$; Bob computes the shared secret by combining his private key $$b$$ with Alice's public key $$g^a$$ via $$(g^a)^b = g^{ab}$$.
 * The whole point is that Alice and Bob need only exchange public information over a channel that an adversary may be eavesdropping on, and can still establish a shared secret. If each party had to also learn the other party's private key in advance over some secret channel they'd previously established, it wouldn't have been a revolutionary idea in 1976. Taylor Riastradh Campbell (talk) 11:47, 10 February 2024 (UTC)

Can a pair of keys do anything other than encryption?
I would be grateful if someone explained to me the complete purpose of public and private keys if there is any type of public-private cryptosystem that does not serve, in its core, for encryption.

From my understanding, this is a simple matter: public keys serve to encrypt data and private keys serve to decrypt data. Thus, the only thing public-private cryptosystems can do is encrypt and decrypt data.

If I understood these systems correctly, the purpose of public-private cryptosystems is in fact not limited to data confidentiality, but any other application (digital cash, password-authenticated key agreement, time-stamping services, etc.) uses encryption because that is the base of pubic-private cryptosystems.

The state of the article at my last edit was quite easier for non-experts, it would be good to have a similar first paragraph in the lead. Have I misunderstand something?

PS: after the first @Taylor Riastradh Campbell's revert of my edit, I investigated the topic before ediiting the lead; after that, I was sure that public-private cryptosystems were limited to encryption, so I was bold to get a faster feedback, I see nothing wrong on doing this.

Emunah00 (talk) 01:41, 18 June 2024 (UTC)

 * An encryption scheme is loosely a system to turn plaintext messages into ciphertexts in a way that can be reversed, with a security goal to conceal any patterns in the plaintext from an adversary. (The formalization is ciphertext indistinguishability.)  In the public-key setting, anyone with a public key can turn plaintexts into ciphertexts, but only those who know the related private key can decrypt the ciphertexts to recover the plaintexts.  Reversibility, and the security goal of concealing patterns in messages, are defining characteristics of encryption.
 * The first public-key cryptosystem ever published, Diffie-Hellman key exchange, is a way for Alice and Bob to agree on a secret key by exchanging only public information that can be eavesdropped. This is public-key key agreement.  Neither one can pick the secret key in advance—they just get a random key out of the procedure, which nobody else knows.  So on its own this is not encryption.  You can build a public-key encryption scheme on top of public-key key agreement, by combining it with a secret-key (authenticated) cipher (e.g., IES), but that is extra structure which is not itself part of public-key key agreement.
 * Public-key signature doesn't involve concealing patterns in messages at all. It is loosely a system where anyone with a public key can use it to verify signed messages, but only those who know the related private key can make signatures that will pass verification.  (The formalization is unforgeability.)  Although there are some signature schemes that encode part of the message in the signature, you can't in general recover a message from a signature—there's no reversibility.
 * Some signature schemes have a subroutine that resembles a very limited form of encryption, mainly those based on the RSA trapdoor function. But you can't simply take a secure RSA-based encryption scheme like RSAES-OAEP or RSA-KEM-with-a-DEM as a subroutine and make a secure signature scheme out of that, or vice versa.  And there's no generic way to turn a public-key encryption scheme into a public-key signature scheme, or vice versa.  There are many public-key signature schemes—most of them, really!—that don't involve the RSA trapdoor function, or any structure that really resembles a public-key encryption scheme as a subroutine.  Examples:
 * Schnorr signature
 * Lamport signature and Merkle signature (based on one-way hash functions only)
 * Rabin signature (loosely related to RSA, sometimes misrepresented in textbooks as a completely broken public-key encryption scheme)
 * BLS digital signature
 * Falcon (signature scheme)
 * Other examples of public-key cryptosystems that don't involve encryption:
 * Public-key key encapsulation provides a way for someone to simultaneously create and send a random secret key to a recipient using the recipient's public key, but like in public-key key agreement, the sender can't choose what the random secret key will be. Modern public-key encryption schemes are built out of public-key key encapsulation, not the other way around.
 * Dual_EC_DRBG is a public-key pseudorandom number generator: anyone can use the public key to expand a secret seed into an arbitrarily long roughly-uniform string of bits (like a normal pseudorandom number generator), but only those who know the private key (like the NSA) can use one output to guess the next output without knowing the seed. (The NSA doesn't get to learn the seed, though, only the next output—it's still not encryption!)
 * A verifiable random function is a system where only those who know a private key can compute a pseudorandom function of given inputs, but anyone who knows the related public key can verify that the outputs are correct. This is more related to signature than to encryption.
 * None of the examples you gave necessarily involve encryption:
 * Digital cash is almost always based on signature, sometimes blind signature as in Ecash, sometimes ordinary signature as in Bitcoin.
 * Password-authenticated key exchange takes passwords as inputs, and returns a random shared key (sometimes together with an indication that the passwords matched), but the parties generally can't choose what the random shared key will be—otherwise, if they chose it in advance, why would they bother with the human-memorable password?
 * Trusted timestamping services are all about signatures, not encryption. One party is trusted to operate a clock and keep a private signing key secret; anyone can submit a message and get a signed timestamped version of it that everyone else, having the public key of the timestamping service distributed, can verify.
 * Taylor Riastradh Campbell (talk) 02:43, 18 June 2024 (UTC)
 * Thank you for your detailed response, I'm sorry for introducing those errors in the lead (if you provided just one very clear example like Diffie-Hellman key exchange in your first or second revert I would have understood).
 * I have a minor question: according to its article, public-key key encapsulation does involve encryption, if I understood it correctly, doesn't it?
 * Do you think it's possible to summarize both public-key cryptosystems that don't envolve encryption taking a common property of all of them, yet keeping it understandable by non-expert readers?
 * Emunah00 (talk) 03:39, 18 June 2024 (UTC)
 * Public-key key encapsulation takes a public key and produces two outputs at once:
 * a random secret key
 * an encapsulation of that secret key, from which the secret key can be recovered only with knowledge of the private key corresponding to the public key
 * But you have no control over what the random secret key will be, other than by running it repeatedly and filtering for ones you like—you can't pick the secret key in advance and find a working encapsulation for it.
 * This can be used as a subroutine in a public-key encryption scheme to send a message, by using the random secret key with an authenticated cipher on the message and transmitting the message's ciphertext alongside the encapsulated secret key:
 * To Encrypt(pubkey, message):
 * (secretkey, encapsulation) := Encapsulate(pubkey)
 * ciphertext := AuthenticatedEncrypt(secretkey, message)
 * return (ciphertext, encapsulation)
 * To Decrypt(privkey, (ciphertext, encapsulation)):
 * secretkey := Decapsulate(privkey, encapsulation)
 * message := AuthenticatedDecrypt(secretkey, ciphertext)
 * return message, or fail if authentication failed
 * Given a public-key encryption scheme, you can also build a public-key key encapsulation scheme. But it is practically always easier to design a secure public-key key encapsulation scheme than it is to design a secure public-key encryption scheme, so essentially all new designs—e.g., the NIST PQCRYPTO submissions—start with key encapsulation and derive encryption from that.
 * Only archaic legacy designs like RSAES-PKCS1-v1_5 and RSAES-OAEP do it the other way around—and even then, they build a very limited public-key encryption scheme out of the RSA trapdoor function that only handles short messages, and then use the limited encryption scheme to transmit a short random secret key, and then use that in a public-key key encapsulation mechanism like I sketched above to encrypt arbitrary-length messages. Taylor Riastradh Campbell (talk) 11:35, 19 June 2024 (UTC)
 * Well, I tried that for the lead, but rather than expound on it in paragraphs of abstract prose defining a property, I tried to illustrate it with two practical examples.
 * The common property is that the cryptosystem involves pairs of keys that are mathematically related, so the public key has one power and the private key has a related power which—as a security goal—can't be derived from the public key or from any use of the cryptosystem interacting with whoever has the private key.
 * The most prominent examples are probably encryption (public key: power to send secret messages; private key: power to receive secret messages that were sent using the public key) and signature (public key: power to verify messages; private key: power to sign messages that will pass verification by the public key), with some other less-common examples like VRFs (public key: power to verify a random function was evaluated; private key: power to evaluate the random function that is verified by the public key).
 * In practice, signature and key agreement are probably the most widely used—just about every web page you load leads to signature and key agreement behind the scenes; public-key encryption, VRFs, PAKEs, and others see much less use in the real world. But public-key key agreement is a little more abstract than public-key encryption, so it's harder to illustrate with an example. Taylor Riastradh Campbell (talk) 13:21, 19 June 2024 (UTC)
 * The most prominent examples are probably encryption (public key: power to send secret messages; private key: power to receive secret messages that were sent using the public key) and signature (public key: power to verify messages; private key: power to sign messages that will pass verification by the public key), with some other less-common examples like VRFs (public key: power to verify a random function was evaluated; private key: power to evaluate the random function that is verified by the public key).
 * In practice, signature and key agreement are probably the most widely used—just about every web page you load leads to signature and key agreement behind the scenes; public-key encryption, VRFs, PAKEs, and others see much less use in the real world. But public-key key agreement is a little more abstract than public-key encryption, so it's harder to illustrate with an example. Taylor Riastradh Campbell (talk) 13:21, 19 June 2024 (UTC)

 * WP:TLDR If I understand your question correctly, I think a simpler view of the system would answer it.

 * Firstly, the system operates on the creation of a related pair of keys. Which one is the public key and which is the private is purely a matter of choice (often enforced by cryptographic systems but it doesn't have to be).

 * Secondly, although one would normally encrypt a message with one key and decrypt it with other, this is also purely a matter of convention. There is nothing preventing the originator of the message decrypting the plain text message with either key and the recipient encrypting it with the partner key to recover the plain text. The intermediate encrypted message is just as encrypted as doing it the other way around. It is only necessary to know in which direction the encrypter processed the message.

 * As you noted: anything can be encrypted as long as it is represented as a stream of binary numbers. A well know public key encryption system, in reality isn't quite. PGP is in fact a symmetric cypher system (in that the same key is used to encrypt and decrypt the actual message). What makes it appear to be a public key system is the public key part of the system is only used to encrypt the symmetric key (individually generated for each message). This makes it substantially more efficient than a naked public key system because public key systems with keys that are large enough to be considered secure are much more computationally expensive than symmetric systems. PGP thus only has to public key encrypt a symmetric key which can be much smaller for the same security and thus the computation is kept to a minimum. 2A00:23C8:9883:A001:6012:33CA:E0B6:6163 (talk) 14:59, 18 June 2024 (UTC)
 * This is a misconception that makes no sense in most cases, and leads to security-destroying blunders in cases where it looks like it might make sense.
 * This misconception makes no sense in most cryptosystems, because public keys and private keys are different kinds of things. For example, in the public-key signature scheme Ed25519, the public key is the encoding of a point $$(x, y)$$ on an elliptic curve, satisfying $$-x^2 + y^2 \equiv 1 - (121665/121666) x^2 y^2 \pmod{2^{255} - 19},$$ and the private key is (or can be hashed to derive) an integer $$s \in [0, 2^{252} + 27742317777372353535851937790883648493)$$ together with a 256-bit string.  Even if you were to misinterpret the private scalar $$s$$ as the $$y$$-coordinate of a public point (and ignore the extra 256-bit string in the private key), only about half of the possibilities satisfy the equation; the rest can't be valid public keys.
 * This misconception makes no sense in most cryptosystems, because public keys and private keys are different kinds of things. For example, in the public-key signature scheme Ed25519, the public key is the encoding of a point $$(x, y)$$ on an elliptic curve, satisfying $$-x^2 + y^2 \equiv 1 - (121665/121666) x^2 y^2 \pmod{2^{255} - 19},$$ and the private key is (or can be hashed to derive) an integer $$s \in [0, 2^{252} + 27742317777372353535851937790883648493)$$ together with a 256-bit string.  Even if you were to misinterpret the private scalar $$s$$ as the $$y$$-coordinate of a public point (and ignore the extra 256-bit string in the private key), only about half of the possibilities satisfy the equation; the rest can't be valid public keys.

 * In the cryptosystems where it kinda sorta looks plausible if you squint, which is really limited to RSA-based cryptosystems, this misconception leads to security-destroying blunders. If you look at an RSA public key as $$(n, e)$$ and an RSA private key as $$(n, d)$$ with $$ed \equiv 1 \pmod{\lambda(n)},$$ and if you look only at the pure RSA trapdoor function $$x \mapsto x^e \bmod n$$ itself (which is not a public-key encryption scheme or a public-key signature scheme), the inverse $$y \mapsto y^d \bmod n$$ is the same function so the roles of $$e$$ and $$d$$ look similar.  But the similarity ends there.  Almost all encryption and signature schemes based on RSA in the real world use $$e = 65537$$ for efficiency (RSA supports some of the cheapest public-key operations, second only to Rabin signature), and derive $$d := e^{-1} \bmod \lambda(n)$$, and have a host of other details on top of the trapdoor function—sometimes called padding schemes—to make a secure encryption scheme, or a host of different details to make a secure signature scheme.  If you try to interchange the public key and the private key in these cases, security is immediately lost because there's no more secrets in the private key—everyone knows it's $$(n, 65537)$$!  More generally, in secure RSA-based cryptosystems like RSA-FDH signature or RSA-KEM key encapsulation or RSAES-OAEP encryption, it is safe to use public exponent $$e$$ as low as 3.  But to resist Wiener's attack and variants like Boneh–Durfee, one must use private exponent $$d \gg n^{0.292}$$ (and it is conjectured that $$d \gg n^{0.5}$$ may be needed).  That is, although the public exponent $$e$$ and the private exponent $$d$$ are syntactically the same kind of thing (exponents in $$\mathbb Z/\lambda(n)\mathbb Z$$), they have completely different security requirements.  So it is not ‘purely a matter of choice’ which one is the public key and which one is the private key.
 * Taylor Riastradh Campbell (talk) 13:02, 19 June 2024 (UTC)

 * WP:TLDR. You are making this more complicated than this needs to be. You can generate the pair of keys how you like. But there is no requirement that one is specifically the public key and other is the private. Though, obviously in any cryptographic system, you have to settle on one or the other. Whichever key that you use to encrypt (and you can use either), you have to use the other to decrypt (and vice versa). 2A00:23C8:9883:A001:783C:2503:45B1:2CB0 (talk) 13:26, 19 June 2024 (UTC)

 * This is not true, and it suggests that you're only familiar with the idealized textbook treatment of a single family of cryptosystems, that is, those based on the RSA trapdoor function. While this pop-science oversimplification of cryptography is common in classroom settings, it's wrong and, if applied in practice, can destroy security of what might have otherwise been a secure cryptosystem.
 * Would you like to explain how to use an Ed25519 public key to create a signature, or cite the literature that explains how to do this? Taylor Riastradh Campbell (talk) 14:11, 19 June 2024 (UTC)
 * Would you like to explain how to use an Ed25519 public key to create a signature, or cite the literature that explains how to do this? Taylor Riastradh Campbell (talk) 14:11, 19 June 2024 (UTC)

title: Talk:Public-key cryptography


text:
Talk:Asymmetric key algorithm

Merge?
This should probably be combined with Public-key cryptography or vice-versa. Rasmus Faber 15:40, 8 Dec 2003 (UTC)

Error: pure nonsense
''Not all asymmetric key algorithms operate in precisely this fashion. The most common have the property that Alice and Bob own two keys; neither of which is (so far as is known) deducible from the other.''

Pure nonsense, in most cases it is simple to generate the public key from the private, but the reverse is intended to be VERY hard. Tacvek 23:13, 18 Apr 2005 (UTC)

 * Are you sure? RSA's two keys are interchangeable: either key can be chosen as the public key.  It is very hard to deduce one given the other in any direction.  Of course, I'm no expert in the overwhelming majority of asymmetric algorithms, but isn't this how most of them work? Vesta 04:42, 19 Apr 2005 (UTC)

 * I think I'm correct (not an expert either), and regardless in practive when a private key is stored enough information to generate the public key is stored with it. Gpg for instance allows recreation of 'public key', from 'private key'. Even if key is considered just the number
 *
 * DSA for example (as far as i can tell from the page) indicates that all 3 components of the public key are required for signing, which makes the public key part of the private for all real intents and purposes. (Note that that is actually only signing, not full encyption.)
 * As for RSA using either key i would assume that there is a reason key e is given out publicly, rather than key d. I suspect it has to do with the fact that e is restricted to 1<e<φ, while key e is not restricted in any such way. Presumably this is because it is significantly easier to find e (public) from d (private) than d (private) from e (public).
 * The final word though is that while perhaps in theory one cannot be easilly derived from the other, in practice the information needed for getting the public key is almost always stored with the private key. I suspect the article sould reflect this fact rather than the misleading one currently there. Tacvek 22:28, 19 Apr 2005 (UTC)

 * Your argument sounds good. If nobody else objects, I'd say that you're in the right to go ahead and change it. Vesta 06:17, 20 Apr 2005 (UTC)

title: Talk:Asymmetric key algorithm


text:
Gift wrapping algorithm

In computational geometry, the gift wrapping algorithm is an algorithm for computing the convex hull of a given set of points.

Planar case
In the two-dimensional case the algorithm is also known as Jarvis march, after R. A. Jarvis, who published it in 1973; it has O(nh) time complexity, where n is the number of points and h is the number of points on the convex hull. Its real-life performance compared with other convex hull algorithms is favorable when n is small or h is expected to be very small with respect to n. In general cases, the algorithm is outperformed by many others (see Convex hull algorithms).

Algorithm
For the sake of simplicity, the description below assumes that the points are in general position, i.e., no three points are collinear. The algorithm may be easily modified to deal with collinearity, including the choice whether it should report only extreme points (vertices of the convex hull) or all points that lie on the convex hull. Also, the complete implementation must choose how to deal with degenerate cases when the convex hull has only 1 or 2 vertices, as well as with the issues of limited arithmetic precision, both of computer computations and input data. The gift wrapping algorithm begins with i=0 and a point p0 known to be on the convex hull, e.g., the leftmost point, and selects the point pi+1 such that all points are to the right of the line pi pi+1. This point may be found in O(n) time by comparing polar angles of all points with respect to point pi taken for the center of polar coordinates. Letting i=i+1, and repeating with until one reaches ph=p0 again yields the convex hull in h steps. In two dimensions, the gift wrapping algorithm is similar to the process of winding a string (or wrapping paper) around the set of points.

The approach can be extended to higher dimensions.

Pseudocode

algorithm jarvis(S) is // S is the set of points // P will be the set of points which form the convex hull. Final set size is i.    pointOnHull := leftmost point in S // which is guaranteed to be part of the CH(S) i := 0 repeat P[i] := pointOnHull endpoint := S[0]     // initial endpoint for a candidate edge on the hull for j from 0 to |S| do // endpoint == pointOnHull is a rare case and can happen only when j == 1 and a better endpoint has not yet been set for the loop if (endpoint == pointOnHull) or (S[j] is on left of line from P[i] to endpoint) then endpoint := S[j]  // found greater left turn, update endpoint i := i + 1 pointOnHull := endpoint until endpoint == P[0]     // wrapped around to first hull point

Complexity
The inner loop checks every point in the set S, and the outer loop repeats for each point on the hull. Hence the total run time is $$O(nh)$$. The run time depends on the size of the output, so Jarvis's march is an output-sensitive algorithm.

However, because the running time depends linearly on the number of hull vertices, it is only faster than $$O(n \log n)$$ algorithms such as Graham scan when the number h of hull vertices is smaller than log n. Chan's algorithm, another convex hull algorithm, combines the logarithmic dependence of Graham scan with the output sensitivity of the gift wrapping algorithm, achieving an asymptotic running time $$O(n \log h)$$  that improves on both Graham scan and gift wrapping.

title: Gift wrapping algorithm


text:
Operation Big

Operation Big was an operation of the Alsos Mission, the Allied seizure of facilities, materiel, and personnel related to the German nuclear weapon project during World War II. It was tasked with sweeping several targeted towns in the area of southwest Germany designated to the French First Army, including Hechingen, Bisingen, Haigerloch, and Tailfingen.

Operating behind German lines the U.S. task force successfully carried out its mission of seizing or destroying all project related assets and capturing its top scientists in the last week of April and first week of May, 1945.

History
Shortly after the liberation of Paris it was decided to bomb German nuclear facilities wherever they lay in order to deprive the Soviet Union of their technology and personnel, unless American troops could get to them first. Worried that French forces might beat the US to Werner Heisenberg's laboratory in Hechingen, Alsos chief Lt-Col Boris Pash hastily organized a flying column of combat engineers from the 1269th Engineer Combat Battalion, the U.S. Sixth Army Group's T-Force intelligence assault force ("Task Force A"). His team reached Horb three days later and headed for Haigerloch while the French forward troops occupied themselves with looking for members of the Vichy Government twenty miles deeper into Württemberg in the Sigmaringen enclave.

Pash and his engineers, accompanied by the Sixth Army Group's Chief of Intelligence, General Eugene Harrison, overran Haigerloch on 23 April 1945.

Here the elated scientists made their first big discovery. As the engineer troops consolidated the group’s position in the town, the ALSOS team shot open a bolted door sealing the entrance to a cave in the side of a cliff. Inside, the team found a large chamber and several smaller rooms crammed with instruments, control boxes, and an array of cylinders described by a frightened German technician as a uranium machine. Though missing its uranium element, the device was an operating atomic pile, captured undamaged.

With help from engineers, the scientists spent two days dismantling the equipment. Three large drums of heavy water, used to control the reaction in the pile, were later found in the laboratory's main chamber and a German scientist told Pash that the reactor's uranium cubes had been concealed beneath hay in a nearby barn.

The task force then proceeded to Hechingen where they found and detained Erich Bagge, Carl Friedrich von Weizsäcker, Max von Laue, and Karl Wirtz, then went on to Tailfingen where they arrested Otto Hahn. Heisenberg, who had left Hechingen on 19 April, was captured by Pash and a small force at his home in Urfeld am Walchensee, on 3 May 1945.

title: Operation Big


text:
User talk:Sureshan

Hello, welcome to Wikipedia. Here are some useful links in case you haven't already found them;

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Wikipedia:Indian wikipedians' notice board
Hi. I would like you to be an active member of Indian wikipedians' notice board. utcursch 07:42, Dec 29, 2004 (UTC)

Kasaragod District
I reverted your image test in the above article. Please use sandbox for such testing. Thanks, Ganeshk  ( talk ) 08:29, 23 April 2006 (UTC)

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title: User talk:Sureshan


text:
Hong Kong Disneyland

Hong Kong Disneyland (abbreviated HKDL; also known as HK Disneyland) is a theme park located on reclaimed land in Penny's Bay, Lantau Island, Hong Kong. It was the first Disneyland in Asia outside of Japan until Shanghai Disneyland in 2016. Hong Kong Disneyland is located inside the Hong Kong Disneyland Resort and is owned and managed by Hong Kong International Theme Parks. It is the most visited theme park in Hong Kong, followed by Ocean Park Hong Kong. Hong Kong Disneyland opened to visitors on Monday, September 12, 2005, at 13:00 HKT. Disney attempted to avoid problems of cultural backlash by incorporating Chinese culture, customs, and traditions when designing and building the resort, including adherence to the rules of feng shui. Notably, a bend was put in a walkway near the Hong Kong Disneyland Resort entrance so good qi energy would not flow into the South China Sea.

The park consists of eight themed areas: Main Street, U.S.A., Fantasyland, Adventureland, Tomorrowland, Grizzly Gulch, Mystic Point, Toy Story Land, and World of Frozen. The newest themed area — World of Frozen, opened on 20 November 2023. There are single tickets and annual passes, called Magic Access, that are available for tourists who visit Hong Kong Disneyland. The theme park's cast members speak Cantonese, English, and Mandarin. Printed guide maps were printed in traditional and simplified Chinese as well as English. Guide maps are now available on the Hong Kong Disneyland mobile app as well as the ability to reserve park visits and other related information for park visits.

The park has a daily capacity of 34,000 visitors — the lowest of all Disneyland parks. The park attracted 5.2 million visitors in its first year, below its target of 5.6 million. Visitor numbers fell 20% in the second year to 4 million, inciting criticisms from local legislators. However, the park attendance jumped by 8% in the third year, attracting a total of 4.5 million visitors in 2007. In 2009, the park attendance again increased by 2% to 4.8 million visitors. The attendance continued to surge and received 5.23 million guests in the 2009/2010 fiscal year. Since the opening of Hong Kong Disneyland, the theme park has hosted over 100 million guests. According to AECOM and TEA, Hong Kong Disneyland is the 13th most visited theme park in the world in 2013, with 7.4 million visitors.

Majority-owned (53%) by the Hong Kong Government but managed by Disney, the park first turned an annual net profit of HK$109million (US$13.97million) for the year ended 29 September 2012. However, it has operated at an increasing loss in 2015, 2016 and 2017. Hong Kong Disneyland currently occupies 27.5 ha and hosts 6–7 million visitors annually. The park capacity will increase to handle up to 10 million visitors annually over a 15-year expansion period.

Early history

Penny's Bay was filled in to provide land for the construction of Hong Kong Disneyland. The bay was previously undeveloped except for the Cheoy Lee Shipyard, which opened in the 1960s.

The city's chief executive, Tung Chee-hwa, was instrumental in introducing the Disneyland project to Hong Kong. When the SARS epidemic devastated the city's economy in 2003, it was hoped that the new Disneyland would help boost confidence in Hong Kong's tourism industry.

Hong Kong Disneyland had one of the shortest construction periods of any Disneyland-style theme park. On 12 January 2003, more than 400 guests celebrated the groundbreaking of Hong Kong Disneyland after the finishing of land reclamation in Penny's Bay. The audience included Tung Chee-hwa; Michael D. Eisner, former chairman and CEO of The Walt Disney Company; Bob Iger, president of The Walt Disney Company; and Jay Rasulo, former president of Walt Disney Parks and Resorts. On 23 September 2004, a special "castle topping ceremony" was held in the park to commemorate the placing of the tallest turret on Sleeping Beauty Castle.

On 12 September 2005, Hong Kong Disneyland was officially opened to the public. The opening ceremony was officiated by Zeng Qinghong, who was then the vice president of China. To help Hong Kong Disneyland grow, the Chinese government had deliberately slowed down the development of Shanghai Disney Resort, which was first conceived in the early 2000s.

Expansion

In January 2012, Hong Kong Disneyland has been in the process of negotiating with the Government of Hong Kong to invest its HK$5 billion profit for new attractions. Further details of the expansion would be announced within a 12-month period from January 2012. A shopping complex and new hotels would be taken into consideration for the new expansion plan.

In Hong Kong financial secretary John Tsang's 2013–14 budget speech, he announced that a new night time parade: "Disney Paint The Night Parade", as well as a themed area featuring characters from the Marvel Universe, will be built in Hong Kong Disneyland. On 8 October 2013 then Walt Disney Parks and Resorts chairman Thomas O. Staggs confirmed the development of the Iron Man Experience.

On 17 February 2014, Hong Kong Disneyland announced its 2012–13 financial results as well as a plan for the third hotel at the resort. The third hotel would be the largest hotel at the resort, featuring 750 rooms with an adventure and exotic theme, and would cost HK$4.26 billion to build. The third hotel, Disney Explorers Lodge, opened on 30 April 2017.

Hong Kong Disneyland was also built with the space for a second park directly across from the entrance to the current park. Disney has not yet announced that the second park is in development. Land is also available for additional hotels other than the three current, but the common thought is that the second park will be built before a fourth hotel. However, it was announced in September 2020 by the Hong Kong Government that Hong Kong Disneyland's option to purchase the 60-hectare expansion site next to the existing park will not be extended after its expiry on 24 September 2020 as it is unable to commit to using the site in the near future.

On 22 November 2016, the Walt Disney Company and the Hong Kong Government announced plans for a multi-year, HK$10.9 billion expansion of Hong Kong Disneyland. The proposed expansion includes a Frozen-themed area (announced for 2021), a Marvel-themed area (opening in phases from 2018 to 2023), a redesigned Sleeping Beauty Castle and hub (announced for 2020), a reimagined attraction (announced for 2021), a new Moana stage show (announced for 2018), and live entertainment.

On 24 May 2018, Hong Kong Disneyland opened the first project part of the multi-year expansion: Moana: a Homecoming Celebration, an atmosphere stage show performed daily at the newly built Jungle Junction venue in Adventureland. The park also gave more information on the coming projects as well as the revised dates for these projects: the shooting dark ride Ant-Man and The Wasp: Nano Battle!, replacing Buzz Lightyear Astro Blasters, opened in 2019 and the new expanded castle will be unveiled in 2020, in time for the park's 15th anniversary. Park officials also confirmed the rumors that the future Frozen-themed area will feature a copy of Epcot's Frozen Ever After and a family roller coaster named Wandering Oaken’s Sliding Sleighs, replacing the previously announced Dancing Sleighs ride, and that the area was opened in 2023.

On 26 January 2020, the park closed due to the ongoing COVID-19 pandemic along with Ocean Park Hong Kong and Shanghai Disneyland Park. It remained closed for nearly five months, reopening on 18 June 2020. It was the second worldwide Disney park to reopen after Shanghai Disneyland. It reopened with similar strict rules as Shanghai Disneyland, which included limited guest attendance, social distancing, temperature checks, and mandatory wearing of face masks. Hong Kong Disneyland closed again from 15 July to 25 September 2020 due to a heavy upsurge in domestic cases. After reopening for approximately two months, it was announced the park would close for a third time on 2 December 2020 due to a rising number of COVID-19 cases in the region. The park reopened on 19 February 2021. The park closed for the fourth time on 7 January 2022 due to the rising number of cases of the Omicron variant, and reopened on 21 April 2022.

In 2023, Hong Kong Disneyland expanded again and created the world's first and largest "Frozen" theme park – "Frozen World", which officially opened to tourists on 20 November of that year. Visitors can experience the adventure journey of Arendelle here.

Timeline

 * 1998
 * August – The Walt Disney Company and the government of Hong Kong announce their intention to construct a themed entertainment park in Hong Kong, the second in Asia, the first in China
 * 1999
 * February – Penny's Bay, Lantau Island is announced as the future site of the Hong Kong Disneyland Resort
 * 10 December – Disney and the Hong Kong Government sign an agreement for building the second Disney Resort in Asia
 * 2003
 * 1 January – Construction on Hong Kong Disneyland Resort begins
 * 2004
 * 22 November – Disney announces that the opening day of the park has been rescheduled from 2006 to 12 September 2005
 * 2005
 * 12 September – Hong Kong Disneyland officially opening ceremony or grand opening and officially opening to the public so officially full formal opening took place at 13:00 HKT officially opening presidented by the Chief Executive of Hong Kong Donald Tsang, Chief Executive Officer of the Walt Disney Company Michael Eisner, Vice President of the People's Republic of China Zeng Qinghong as Beijing declaration congress and President of the Walt Disney Company Bob Iger officially marked to cutting scissors ribbon.
 * 2006
 * June – HKDL announces to release Summer Passes to boost its first year attendance
 * 13 July – Autopia, Stitch Encounter and UFO Zone opens in HKDL as first part of its expansion
 * August – Exclusive treats are provided for Summer Pass holders so as to further boost the park's attendance
 * 4 September – More than 60,000 Summer Passes have been sold since 1 July. However, Hong Kong Disneyland has missed its target of 5.6 million in the first year of operation, with only about 5 million guests entered the park since the opening
 * 28 September – HKDL launches its annual pass
 * 30 September – Disney's Halloween celebration held for the first time through 31 October 2006
 * 14 December – HKDL announced three new attractions to be added to the park in 2007–2008
 * 2007
 * 26 June – HKDL revealed its attractions for the park's 2007 summer – "Mickey's Summer Blast" and announcement of Mickey's Water Works Parade and Animation Academy's opening date – 14 July 2007
 * 19 December – HKDL revealed 4 new attractions and entertainment venues to open in 2008 with "It's a Small World": Muppet Mobile Lab, High School Musical Celebration, Turtle Talk with Crush and the Art of Animation
 * 2008
 * 28 April – "It's a Small World" opens in HKDL as first extension of Fantasyland
 * 2009
 * 10 July – The Legislative Council of Hong Kong approved the three land expansion of HKDL
 * 13 December – Groundbreaking ceremony for the construction of the three land expansion

 * 2010
 * 12 September – HKDL celebrates its 5th year milestone
 * 2011
 * 21 January – HKDL hosts the year-long 5th anniversary programme "Celebration in the Air"
 * 18 November – Toy Story Land opens
 * 2012
 * 14 July – Grizzly Gulch opens
 * 2013
 * 17 May – Mystic Point opens
 * 7 October – Iron Man Experience is announced
 * 6 November – Disney Paint the Night parade is announced
 * 2014
 * February – Construction of Iron Man Experience begins
 * 1 October – Nighttime parade Disney Paint the Night starts to run
 * 2015
 * 12 September – HKDL celebrates its 10th year milestone
 * 17 November – HKDL hosts the year-long 10th anniversary programme "Happily Ever After"
 * 17 December – Fairytale Forest, a new attraction in Fantasyland, opens
 * 21 December – Mickey and the Wondrous Storybook replaces The Golden Mickeys as the new flagship live stage show of Fantasyland
 * 2016
 * 11 June – Star Wars: Tomorrowland Takeover, a Star Wars-themed seasonal event, launches
 * 22 November – HKDL announces its new expansion and development plan, which includes the construction of a Frozen-themed area, introduction of Marvel-themed rides, redesigning of the Sleeping Beauty Castle and more
 * 2017
 * 11 January – Iron Man Experience opens
 * 30 April – Disney Explorers Lodge opens
 * 31 August – Buzz Lightyear Astro Blasters closed to be replaced by Ant-Man and The Wasp: Nano Battle!
 * 13 October – Construction begins on Moana, Frozen, and Marvel attractions
 * 14 December – Royal Princess Garden opens temporarily at Main Street, U.S.A.
 * 2018
 * 1 January – The Sleeping Beauty Castle closed for redesign, causing the Disney in the Stars fireworks to be discontinued as well.
 * 15 March – We Love Mickey! debuts at Main Street, U.S.A.
 * 25 May – Moana: A Homecoming Celebration opens at Jungle Junction in Adventureland
 * 7 November – We Love Mickey! Birthday Edition debuts at Main Street, U.S.A. as part of Mickey Mouse's 90th Anniversary
 * 2019
 * 16 February – The "Heart" Gazebo at Fantasyland closed to give way for the Frozen Land
 * 31 March – Ant-Man and The Wasp: Nano Battle! opens
 * 21 June – Royal Princess Garden and Bibbidi Bobbidi Boutique at Main Street, U.S.A. has closed for relocation to Fantasyland
 * 1 July – Bibbidi Bobbidi Boutique at Fantasyland has officially opened to the public

 * 2020
 * 26 January – The park closed due to the COVID-19 pandemic.
 * 18 June – Following a nearly five-month closure, the park reopened to the public with new and enhanced health and safety measures.
 * 15 July – The park closed for the second time due to a rising number of COVID-19 cases.
 * 12 September – While closed, the park celebrated its 15th anniversary.
 * 24 September – Hong Kong Disneyland's option to purchase the adjacent expansion site expired and will not be renewed
 * 25 September – The park reopened to the public, implementing reduced operations, including closures on Tuesdays and Thursdays (except public holidays and special days designated by the resort from time to time).
 * 21 November – The park's centerpiece castle, now called Castle of Magical Dreams, was officially unveiled.
 * 2 December – The park closed for the third time due to a rising number of COVID-19 cases.
 * 2021
 * 19 February – The park reopens for the third time.
 * 17 November – The park closed for one day following a single COVID-19 exposure from a park guest.
 * 2022
 * 7 January – The park closes for the fourth time due to fears of a COVID-19 surge of the Omicron variant.
 * 21 April – The park reopens for the fourth time.
 * 18 June – Momentous debuts.
 * 2023
 * 1 September – The park increased operations to be opened 6 days a week, with closures occurring on Wednesdays instead of Tuesdays and Thursdays (except public holidays and special days designated by the resort from time to time).
 * 20 November – World of Frozen is opened to the public, in honor of the film's 10th-anniversary celebration and as part of the Disney 100 Years of Wonder celebration.
 * 2024
 * 25 April – A new daytime show, Find Your Super Power: Battle for Stark Expo, and a new nighttime show, Find Your Super Power: Battle in the Sky, were both debuted in Stark Expo within Tomorrowland, as part of the "Marvel: Season of the Super Heroes" celebration.

 * 2024
 * Stark Expo

Park layout and attractions

The park, partially in Islands District and Tsuen Wan District, is divided into "lands" (themed areas) and well-concealed backstage areas. On entering a land, a guest is completely immersed in a themed environment and is unable to see or hear any other realm. The idea behind this was to develop theatrical "stages" with seamless passages from one land to the next. The public areas occupy approximately 27.4 ha. When the park initially opened, it consisted of only four themed areas instead of the traditional five lands:
 * Main Street, U.S.A., designed to resemble an early 20th-century Midwest town;
 * Adventureland, featuring jungle-themed adventures;
 * Fantasyland, bringing to life characters from fairy tales and Disney films;
 * Tomorrowland, an optimistic vision of the future.

On 30 June 2009, Donald Tsang, the then Chief Executive of Hong Kong, announced that the expansion of Hong Kong Disneyland had been approved by the Executive Council. The park received three new themed lands — Grizzly Gulch, Mystic Point and Toy Story Land — all located outside the Disneyland Railroad track, south of the current area.

 * Toy Story Land, based on the Disney·Pixar film series Toy Story. Opened 18 November 2011.
 * Grizzly Gulch, reminiscing an abandoned mining town set amidst mountains and woods. Opened 14 July 2012.
 * Mystic Point, heart of a dense, uncharted rain forest where supernatural events take place. Opened 17 May 2013.

On 2 May 2017, the Executive Council approved another multi-year expansion of Hong Kong Disneyland, adding two new themed lands — World of Frozen and Stark Expo — to the park.

 * World of Frozen, themed to the popular Disney franchise Frozen. Opened on 20 November 2023.
 * Stark Expo, inviting guests to combat villains with Marvel superheroes. Opening in 2024.

Throughout the park are 'Hidden Mickeys', or representations of Mickey Mouse heads inserted subtly into the design of attractions and environmental decor.

An elevated berm supports the narrow gauge Hong Kong Disneyland Railroad (built by Severn Lamb) that circumnavigates the park.

Lands of Hong Kong Disneyland
The park currently has eight themed areas hosting various rides, shops, restaurants, and live entertainment.

Main Street, U.S.A.
Inspired by the Main Street, U.S.A. in Disneyland, the buildings of this Main Street are almost identical to those in Anaheim. Like other Disney theme parks, Hong Kong Disneyland's Main Street, U.S.A. serves as the entrance of the park. Plans originally featured a restaurant under the Railroad station, but were scrapped due to budget reasons. The decor is small-town America from the years 1890–1910.

Though being very similar to Anaheim's main street, the theme is heavily influenced by European immigrants. Plaza Inn — which has the identical exterior design as the one in Disneyland — mimics a classical Chinese eatery that was created by a wealthy American couple who were infatuated with Chinese culture. Another restaurant, the Market House Bakery is reminiscent of a bakery founded by a Viennese pastry chef who brought the world's most famous desserts from the Austrian imperial court.

Unlike Main Streets from other parks, Main Street at Hong Kong Disneyland is built mainly of wood instead of stone. There are no horse-drawn streetcars, though tracks for another of the Main Street Vehicle can be seen in concept art.

At the end of Main Street is the Castle of Magical Dreams. Renewed in 2020, it has double the height of the previous Sleeping Beauty Castle, the nodes are integrated with symbols relating to 13 princesses.

Adventureland
Hong Kong Disneyland's Adventureland is the biggest among all Disney parks. It features a large island area home to Tarzan's Treehouse, which is circled by the Jungle Cruise (Jungle River Cruise) — much like the Rivers of America in most Frontierland theme areas. The Adventureland is also home to the "Festival of the Lion King" show. The new atmosphere stage show "Moana: a Homecoming Celebration" debuted on 25 May 2018 at Jungle Junction. A new outdoor venue. it is the first part of the multi-year expansion being unveiled to the public.

Fantasyland
Fantasyland features Castle of Magical Dreams (formerly Sleeping Beauty Castle) as its icon. It also has several attractions based on Disney films such as The Many Adventures of Winnie the Pooh, Dumbo the Flying Elephant, It's a Small World and Cinderella's Carousel. There is also Fantasy Gardens where costumed Disney characters can be met, and a Fairy Tale Forest.

Tomorrowland
Tomorrowland at Hong Kong Disneyland is themed to a SpacePort which features an emphasis on metallic trim, dominated by blue and purple hues. Since the opening of the park, unique attractions have been added into the Hong Kong's Tomorrowland, such as a new Autopia and Stitch Encounter. The first ever Marvel attraction in a Disney theme park, The Iron Man Experience, opened on 11 January 2017 in an area previously envisioned for a Star Tours-type attraction. The land also featured Buzz Lightyear Astro Blasters on opening day, but that was replaced with Ant-Man and The Wasp: Nano Battle!, which opened on 31 March 2019. Hong Kong Disneyland announced that the attractions will be redesign and become part of Stark Expo.

Toy Story Land
Opened on 18 November 2011, Toy Story Land is the first new themed land since the opening of Hong Kong Disneyland in 2005. It is located to the west side of the park, behind Fantasyland. Toy Story Land is themed using bamboo to act as giant blades of grass surrounding the area. The themed land makes use of characters from the Toy Story movies, such as an enlarged Woody, Rex, an oversized paper plane, and Luxo Jr.

Toy Story Land was marketed by the park as "Asia exclusive". For some time its only counterpart, Toy Story Playland, is located at Walt Disney Studios Park in Marne-la-Vallée, France. Since Toy Story Land became popular at this park, it will become more common. One at Disney’s Hollywood Studios in Orlando opened in June 2018, and one in Shanghai Disneyland opened on April 26, 2018.

Grizzly Gulch
Opened on 14 July 2012, this land is the Hong Kong equivalent of Frontierland and Critter Country. The themed land reminisces an abandoned mining town called "Grizzly Gulch", set amidst mountains and woods. The centrepiece structure is Big Grizzly Mountain Runaway Mine Cars, inspired by Grizzly Peak in Disney California Adventure Park. The town was set to be founded 8 August 1888 — the luckiest day of the luckiest month of the luckiest year — by prospectors looking to discover gold.

Mystic Point
Opened on 17 May 2013, Mystic Point is a new themed land in Hong Kong Disneyland. It is also the final area opened in Hong Kong Disneyland's current expansion. It is set in 1909 at an adventurer's outpost established in 1896 in a dense, uncharted rain forest surrounded by mysterious forces and supernatural events. The site features Mystic Manor, home of Lord Henry Mystic, a world traveler and adventurer and his mischievous monkey, Albert.

World of Frozen
A land behind Fantasyland hosts two rides themed to the movie Frozen. World of Frozen is set in the fictional Kingdom of Arendelle. The land features two rides, a sleigh-style family rollercoaster, called Wandering Oaken's Sliding Sleighs, and a Frozen dark ride similar to Frozen Ever After at EPCOT. It was originally set to open in 2020, but the opening date was delayed to 20 November 2023, due to the COVID-19 pandemic.

Stark Expo
On 22 November 2016, it was announced that Tomorrowland would be partly transformed into a Marvel-themed area, as part of a massive six year expansion plan. This expansion would see the replacement of Buzz Lightyear Astro Blasters by an attraction featuring Ant-Man and The Wasp, named "Ant-Man and The Wasp: Nano Battle!" for 2019 and the construction, on the former Autopia site, of a major E ticket attraction, "Avengers Quinjet", based on the Avengers franchise to be completed by 2024.

Entertainment and celebrations
Seasonal entertainment, such as "Disney's Haunted Halloween", "A Sparkling Christmas", and "Disney's Chinese New Year", are held in the park to celebrate major holidays.

Disney Paint the Night
Paint the Night debuted on 11 September 2014. It is a successor of the Main Street Electrical Parade and the first fully LED parade Disney has ever created. It features seven original floats containing over 740,000 individual lights. According to David Lightbody, Director of Entertainment and Costuming of the resort, the creative team spent over 2 years and developed over 1,000 scenic and lighting designs to ensure the parade.

Follow Your Dreams and Momentous
With the completion of Sleeping Beauty Castle's transformation into the Castle of Magical Dreams, new daytime and nighttime shows were introduced.

Follow Your Dreams, the daytime show, debuted on 30 June 2021, and is Hong Kong Disneyland’s first outdoor castle stage show. The show involves Mickey Mouse, his friends, and other Disney characters as they take the audience on a journey to inspire them to never give up on their dreams.

Momentous, the nighttime spectacular, debuted on 18 June 2022. Billed as “The Most Magical Show on Earth”, Momentous tells the story of life and the moments it brings through the lens of Disney and Pixar stories and music. The spectacular, originally known as Cherish the Memories, was designed during the castle transformation.

Both shows were slated to premiere in 2020 for Hong Kong Disneyland’s 15th anniversary celebration (in fact, Momentous uses the anniversary anthem "Love the Memory" as its main theme), but were delayed due to the COVID-19 pandemic.

"We Love Mickey" Projection Show
This spectacular was designed to fill the void between the closure of Disney in the Stars as the castle underwent its transformation; this nightly show of approximately 15 minutes is described as a surprise celebration that will transform the buildings along Main Street, U.S.A. into a canvas of vibrant, colorful visuals that pay tribute to Mickey Mouse's major milestones. It was permanently replaced by Momentous.

Park celebrations
Hong Kong Disneyland has organised entertainment and a number of shows as part of the festive celebrations to attract more visitors, especially young adults.

One of the events is the world's exclusive Disney's Haunted Halloween, which is the only Magic Kingdom-themed park in the world to celebrate the Halloween season with frightening walk-through attractions. Even though the attractions are full of living haunts and spectres that appear around corners, Disney tradition is preserved and gory scenes are excluded. It was later replaced by Disney Halloween Time event for serious challenge.

Amenities
Hong Kong Disneyland gives out free birthday badges to people celebrating their birthday at Hong Kong Disneyland. Name tags are also available when you ask the cast members. One of the special features of Hong Kong Disneyland is that there are free Disneyland themed stickers given out in the park and hotels. Visitors may ask cast members for these exclusive stickers. Each sticker is themed by an individual Disney character.There are also select cast members who wears stashes offering opportunities for pin-trading.

Hong Kong Disneyland: The Grand Opening Celebration Album
Hong Kong Disneyland: The Grand Opening Celebration Album was the soundtrack for the grand opening ceremony of Hong Kong Disneyland at Hong Kong Disneyland Resort. Much of the album are Cantonese or Mandarin cover of theme songs of animated Disney films. The package contains a DVD featuring music videos. The album does not contain any music used in the park.

Track listing

 * Released: 2 September 2005
 * Label: Sony Music Entertainment (Hong Kong)
 * Language: Cantonese and Mandarin
 * Status: Out of print

 * 1) Jacky Cheung – "Let the Wonder Soar" (讓奇妙飛翔) (Cantonese)
 * 2) Twins – "It's a Small World"
 * 3) Eason Chan – "A Whole New World" (from Aladdin)
 * 4) Karen Mok – "When You Wish Upon a Star" (from Pinocchio)
 * 5) Twins – "Mickey Mouse Theme"
 * 6) Jolin Tsai – "Under the Sea" (from The Little Mermaid)
 * 7) Kelly Chen & Kellyjackie – "On a Date With Him to Disneyland" (他約我去迪士尼)
 * 8) Nicholas Tse – "Bare Necessities" (from The Jungle Book)
 * 9) CoCo Lee – "Colors of the Wind" (from Pocahontas)
 * 10) Joey Yung – "Undying True Love" (from Beauty and the Beast)
 * 11) Kelly Chen – "Reflection" (from Mulan)
 * 12) Harlem Yu – "Can You Feel the Love Tonight" (from The Lion King)
 * 13) Jacky Cheung – "Let the Wonder Soar" (讓奇妙飛翔) (Mandarin)

DVD
 * Subtitles: Traditional Chinese
 * Region Code: All region

 * 1) "Let the Wonder Soar" (讓奇妙飛翔) music video – Jacky Cheung
 * 2) "On a Date With Him to Disneyland" (他約我去迪士尼) music video – Kelly Chen & Kellyjackie
 * 3) Cars trailer
 * 4) The Chronicles of Narnia: The Lion, The Witch and the Wardrobe trailer
 * 5) Chicken Little trailer
 * 6) Sky High trailer

MTR
The park is accessible on the MTR via the purpose-built Disneyland Resort line, a themed shuttle train service between the Disneyland Resort station adjacent to the park, and Sunny Bay station, where passengers can transfer to the Tung Chung line for access to Hong Kong Island, Kowloon, or Tung Chung. The line runs modified Metro Cammell M-Trains on the 3.5 km non-stop route. The trains have been converted to run fully automatically without drivers.

Bus

Long Win Bus operates 3 regular routes to the Disneyland Resort Public Transport Interchange in front of the park.

Route R8 is a circular route running between Disneyland and the Lantau Link Toll Plaza Bus Interchange. The latter can be accessed by any of the routes with the A or E prefixes (e.g. A11 or E32), and is always the first stop after crossing the Tsing Ma Bridge. It is the only all-day route serving the park, and is jointly operated with vehicles from Citybus.

Two additional regular routes, running on weekends and public holidays only, provide direct service between other places in the New Territories and Disneyland. They are route R33 to Tuen Mun station, connecting to the MTR, and route R42 to Tai Wai station via Tsuen Wan and Sha Tin. For both routes, one trip departs towards Disneyland in the mornings and the return trip departs approximately 20 minutes after the evening fireworks display.

In addition to the above regular trips, seven special routes (including one cross-harbour route) operate to and from Disneyland before and after special events at the park, of which two are operated by Citybus and the other five by Long Win Bus.

Certain midday and late evening trips of Citybus route B5 between the Hong Kong–Zhuhai–Macau Bridge Hong Kong Port and Sunny Bay station are routed via Disneyland.

2005/2006 Overcrowding problems
Just before the grand opening, the park was criticised for overestimating the daily capacity. The problem became apparent on the charity preview day on 4 September 2005, when 30,000 locals visited the park. The event turned out to be a disappointment, as there were too many guests. Wait times at fast food outlets were at least 45 minutes, and wait times at rides went up to 2 hours.

Although the park's shareholders and the Hong Kong Government set pressure upon the park to lower the capacity, the park insisted on keeping the limit, only agreeing to relieve the capacity problem by extending the opening time by one hour and introducing more discounts during weekdays. However, the park stated that local visitors tend to stay in the park for more than nine hours per visit, implying that the mentioned practices would do little to solve the problem.

During the Lunar New Year 2006, many visitors arrived at the park in the morning bearing valid tickets, but were refused entry, because the park was already at full capacity. Some disgruntled visitors, mainly tourists, attempted to force their way into the park by climbing over the barrier gates. Disneyland management was forced to revise their ticketing policy and designated future periods close to public holidays as 'special days' during which admission would only be allowed through a date-specific ticket. Ticket prices during the week were changed to reflect cheaper prices. Meanwhile, weekend prices were raised. The prices were changed in an attempt to crowd-control so the crowds would be more even throughout the week and therefore the lines would not be as bad on weekends.

Public relations
Disney initially refused to release the attendance figures after media reports surfaced saying the park's attendance numbers might be lower than expected. Disney finally declared on 24 November 2005, that Disney had over 1 million guests during its first two months of operation.

In response to negative publicity locally and to boost visitor numbers, Hong Kong Disneyland offered $50 discounts for admission tickets to holders of Hong Kong I.D. cards in the period before 2005 Christmas. Also, from March to June 2006, the park offered Hong Kong I.D. card holders the opportunity to purchase a two-day admission ticket for the price of a single day ticket.

Attendance
The significant decline in attendance between 2020 and 2023 is due to the COVID-19 regulations imposed in Hong Kong, which included, during several periods, temporary closure of the Resort, reduction in Park capacity, quarantine measures and vaccinations required for visitors entering Hong Kong.

In popular culture
In the 2012 Indian Tamil-language musical romantic comedy film Podaa Podi, a song depicting the relationship between a father and son, written by Vaali and sung by Silambarasan himself, was shot with him and his 1 year old nephew Samarth at Hong Kong Disneyland, making it the first Tamil film to be shot there.

The hit Indian sitcom Taarak Mehta Ka Ooltah Chashmah filmed episodes 1470 to 1478 at Hong Kong Disneyland, where various show characters experienced the attractions.

The music video for the song "Boss" by MIRROR was filmed at Hong Kong Disneyland in 2021.

title: Hong Kong Disneyland


text:
Operation Harborage

Operation Harborage was an operation to capture German nuclear energy program scientists, materiel, and facilities in southwestern Germany in the waning days of World War II.

History
Part of the Allied Alsos Mission, Operation Harborage was led by Manhattan Project intelligence division chief Col. John Lansdale, Jr. on behalf of project head General Leslie Groves, under the direction of Alsos commander Col. Boris Pash. It was carried out by Alsos team members assisted by combat engineers from the 1269th Engineer Combat Battalion, the U.S. Sixth Army's T-Force intelligence assault force.

Shortly after the liberation of Paris it was decided to bomb German nuclear facilities wherever they lay in order to deprive the Soviet Union of their technology and personnel, unless American troops could get to them first. In late April 1945 Harborage teams were directed toward the Black Forest cities of Hechingen, Bisingen and Haigerloch. These centers of the relocated German effort were all scheduled to be seized by the French and occupied by them post-war.

By cutting ahead of the French First Army's forward troops and operating behind enemy lines American technical intelligence units swept the area clean, seizing and transporting off what they could and destroying the rest. The result left the French deprived of a share of the boost German technology and brainpower provided other Allies through the Cold War; these ended up divided among the U.S. (which reaped the lion's share), Soviet Union, and Britain.

title: Operation Harborage


text:
Utrecht Science Park

Utrecht Science Park (also known as De Uithof) is a neighbourhood in Utrecht and the largest science park in the Netherlands. It is located to the east of the city. It is the largest campus of Utrecht University. Apart from the faculties of Law, Humanities and University College Utrecht, most of the university buildings are located in Utrecht Science Park. It is also a main location of the HU University of Applied Sciences Utrecht and the University Medical Center Utrecht, and houses the main university library, student housing and botanical gardens.

History
The Dutch government purchased a plot of land of approximately 300 hectares for Utrecht University in 1958. The area was named "De Uithof", after a local farm. The first building, currently known as the Marinus Ruppert Building, opened in 1961.

The city council decided to officially rename De Uithof to "Utrecht Science Park" in 2018.

Transportation
On 14 December 2019, the Uithoflijn line 22 of the Utrecht sneltram (light rail) system opened, connecting Utrecht Centraal railway station to De Uithof. It replaced bus line 12 which used bi-articulated buses. The Uithoflijn has 5 tram stops in De Uithof: Padualaan, Heidelberglaan, UMC, WKZ / Máxima and the tram terminal P+R Science Park.

The tram stop P+R Science Park has a large park-and-ride facility, designed by KCAP, construction of which began in August 2011.

Buildings in De Uithof
Some of the buildings on De Uithof have an unusual architecture, and some have won prizes for their architecture. The Educatorium, designed by Rem Koolhaas (1997), contains a glass-bottomed walking bridge and circular walls. The Minnaertgebouw used to contain a large basin that was used to collect rain water, and its outer wall is supported by large characters, M, I, N, N, A, E, R, T. The Universiteitsbibliotheek (University Library), designed by Wiel Arets (2004), is known for its spacious interior and black exterior. All three of these buildings are featured in the book 1001 Buildings You Must See Before You Die.

University buildings
This is a partial list of buildings at the Utrecht Science Park. The official names of all of the buildings are found here. Many of the buildings are named after scientists that worked in a field which is similar to the specialization of the occupants of the building. The Dutch word "gebouw" means "building".
 * Aardwetenschappengebouw (Earth Sciences Building) - geoscience
 * Bestuursgebouw – board, management and administration of Utrecht University
 * Buys Ballotgebouw (BBG), named after meteorologist C. H. D. Buys Ballot - experimental physics
 * Caroline Bleekergebouw, named after physicist and instrument maker Caroline Bleeker - workshop for scientific instruments
 * David de Wiedgebouw, named after pharmacologist David de Wied - pharmacology
 * Educatorium - lecture halls
 * Hans Freudenthalgebouw, named after mathematician Hans Freudenthal - mathematics
 * Hijmans van den Berghgebouw, named after physician Abraham Albert Hijmans van den Bergh – (bio)medical education
 * Kruytgebouw (formerly known as Trans-3), named after chemist Hugo R. Kruyt - chemistry, business startups
 * Leonard S. Ornsteinlaboratorium, named after physicist Leonard Ornstein - experimental physics
 * Marinus Ruppertgebouw (formerly known as Trans-1), named after pedagogue Marinus Ruppert, who started the development of buildings on De Uithof - lecture and workshop halls, computer hall
 * Martinus J. Langeveldgebouw (formerly known as Centrumgebouw Zuid), named after Martinus J. Langeveld, Faculty of Social Sciences founder - social science
 * Minnaertgebouw, named after astronomer Marcel Minnaert - physics, geoscience, student services
 * Nicolaas Bloembergengebouw, named after physicist Nicolaas Bloembergen – science, NMR spectroscopy
 * Robert J. Van de Graafflaboratorium, named after physicist and instrument maker Robert J. Van de Graaff - particle accelerator for physics
 * Sjoerd Groenmangebouw (formerly known as Centrumgebouw Noord), named after sociologist Sjoerd Groenman - social science, student services
 * Stratenum, named after physician W. van Straaten – medical education
 * Universiteitsbibliotheek Uithof - Main library
 * Victor J. Koningsbergergebouw, named after biologist Victor Jacob Koningsberger - medicine, geoscience, other science
 * Willem C. van Unnikgebouw (formerly known as Trans-2), named after bible scholar Willem C. van Unnik - social science

Student housing
There are five housing locations with a total of around 3000 rooms, with more under development:

 * Cambridgelaan, built in 1998. 1002 rooms.
 * De Bisschoppen (the Bishops,) built in 2006. 552 rooms.
 * Casa Confetti, built in 2008. 377 rooms.
 * Johanna, built in 2015. 655 rooms.
 * Campus USP 030, built in 2020. 400 rooms.

Convenient facilities

 * SPAR
 * Olympos

title: Utrecht Science Park