H Dagdougui

R Minciardi

A Ouammi

M Robba

R Sacile

Modelling and control of a hybrid renewable energy system to supply demand of a green-building

Keywords: DSS, optimization, wind energy, PV, smart grid

Renewable energy sources are an "indigenous" environmental option, , economically competitive with conventional power generation where good wind and solar resources are available. Hybrid plants can help in improving the economic and environmental sustainability of renewable energy systems to fulfil the energy demand. The aim of this paper is to present the architecture of a Decision Support System (DSS) that can be used for the optimal energy management at a local scale through the integration of different renewable energy sources. The integrated model representing a hybrid energy generation system connected to the grid is developed. It consists of PV and solar thermal modules, wind turbine and biomass plant. Moreover, a framework is presented for the optimization of the different ways to ensure the electrical and thermal energy demand of the microgrid as well as the water demand, with specific reference to two main cases for the real time energy optimal control: the presence/absence of a storage system. Finally, the optimization model has been applied to a case study.

Introduction

The sustainable security of energy supply, led both developed and developing countries to make and implement new policies to improve efficiency in energy consumption, to adopt new alternatives like renewable energy systems. To face the economic, social, technological and environmental challenges, the need for energy conservation as well as for developing renewable technologies becomes ever more critical. As reported by [START_REF] Juan | A hybrid decision support system for sustainable office building renovation and energy performance improvement[END_REF], in the EU and US, buildings energy consumption has even exceeded the energy consumption of the industrial and transportation sectors. Renewable energy utilization is one of the most important aspects of green buildings. The wind and solar energy are freely available and environmental friendly. One common disadvantage of these resources, is their unpredictable behaviour, in addition, the variation of these sources may not match with the time distribution demand [START_REF] Yang | Optimal sizing method for stand-alone hybrid solar-wind system with LPSP technology by using genetic algorithm[END_REF]). Furthermore, the wind energy systems may not be technically viable at all sites because of low wind speeds and being more unpredictable than solar energy. As to solve this drawbacks, the complementary combination of each component characteristic may lead to enhancement of system efficiency and reliability. In addition, combined utilization of these renewable energy sources are therefore becoming increasingly attractive and are being widely used as alternative of oil-produced energy (Nema et al. [2009]). Hybrid renewable energy systems are becoming popular for remote area power generation applications due to advances in renewable energy technologies and subsequent rise in prices of petroleum products, and due to the possibility of attenuating fluctuations in produced power. Economic aspects of these technologies are sufficiently promising to include them in developing power generation capacity for developing countries (M.K Deshmukh and S. S Deshmukh [2008]). Hybrid systems can be considered as a reasonable solution, capable to support systems that cover the energy demands of both stand-alone and grid connected consumers. Commonly, it consists of a mix of two or more energy sources used jointly to provide increased system efficiency as well as greater balance in energy supply. In literature, several papers have studied the design and planning of hybrid renewable energy systems (for example: [START_REF] Paska | K1os, Hybrid power systems -An effective way of utilising primary energy sources[END_REF]; [START_REF] Ashok | Optimised model for community-based hybrid energy system[END_REF]; Ekren and Yetkin Ekren [2008]). The aim of this paper is to present the architecture of a Decision Support System (DSS) that can be used for the hourly energy management of a mix of renewable energy systems. Specifically, an integrated model representing a hybrid energy generation system (characterized by solar plate collector, PV, biomass, wind and battery storage) connected to the grid is developed. The approach is based on mathematical modelling of each component, then an optimization problem is solved in order to better manage and control the energy flow so to ensure reliable supply of demand. The hybrid energy generation system for a general building connected to the electrical network (that is considered in this work) is reported in Figure 1. This hybrid system consists of one PV module, one wind turbine, one biomass plant, one solar flat plat collector, and one battery to store electricity. The optimization of such system aims to generate energy satisfying the demands in real time (i.e., heating demand, electrical demand and water demand) thus taking into account the available renewable energy resources in each time interval. The flat plat collector and biomass plant are uniquely used to ensure heating demand. Either energy produced by the wind turbine or the energy produced by the PV module can be directly used to satisfy a part of the electrical demand as well as the water demand through pumping, and/or can contribute to supply the heating demand. The electricity surplus from wind turbine and the PV module can be sent to the storage battery or/and sold to the network. The battery storage system can receive electrical energy from PV module and wind turbine and can provide free energy for heating, electricity, and pumping needs in cases of deficit in electricity. Furthermore, the network connection offers the possibility to purchase electricity in case of failure of the storage system.

The system model

In particular, the following entities are defined: The power output from the wind turbine unit is expressed as a function of the wind speed, In fact, a linear wind model [16] assumes a linear (affine) dependence (within the interval [v c , v r ]) of the wind turbine power output, t wt P , on the current wind speed at the hub height t v , t=0,…,T-1, being T the time horizon in hour. The following equation is used to simulate the electrical power output of the wind turbine [START_REF] Notton | Decentralized wind energy system providing small electrical loads in remote areas[END_REF]): ,

                  f t f t r r r t c c r c t r c t t wt v v v v v p v v v v v v v p v v P   0 0 t=0,..,T-1 (1)
where r p is the rated electrical power, c v is the cut in wind speed, r v is the rated wind speed, and f v is the cut off wind speed.

In general, the wind speed measurements are given at a height different than the hub height of the wind turbine, the following equation is used to evaluate the wind speed at the desired height [START_REF] Rodolfo | Multi-objective design of PV-wind-diesel-hydrogen battery systems[END_REF]):

) 0 ln( ) 0 ln( z data H z hub H t data v t v  t=0,..,T-1 (2)
Where t v is the wind speed at the height of the hub, data H is the height of the measurement, hub H is the hub height, 0 z is the surface roughness length, and t data v is the wind speed at the height of the measurements.

Energy from the PV module

The output power generated from the PV module, with respect to the solar radiation, can be calculated using the following formula [START_REF] Hocaoglu | A novel hybrid (wind-photovoltaic) system sizing procedure[END_REF]):

t pc f PV pv t pv G p S P    t=0,..,T-1 (3)
where pv S is the solar cell array area, PV  is the module reference efficiency, f p is the packing factor, pc  is the power conditioning efficiency, and t G is the hourly irradiance.

Energy from the biomass heating plant

Energy provided by the biomass heating plant depends on the used biomass quantity t u [m 3 hour -1 ], the biomass volumetric mass, VM [kg m -3 ] (i.e., the ratio between the dry mass [kg] and the volume [m3]), the lower heating value, LHV [MJ kg -1 ]. The LHV assumes that the latent heat of vaporization of water in the fuel and the reaction products is not recovered. Then, it can be calculated once higher heating value (HHV) and moisture content (MC) are known. The HHV is the total energy release in the combustion with all of the products at 273 K in their natural state when water has released its latent heat of condensation. In the considered work, the HHV is evaluated from the basic data analysis of biomass. The biomass MC [%] represents the water amount present in the biomass and it can be expressed as a percentage of the dry weight. As regards production plant, the plant is supposed to operate at the maximum productivity level. The following equation states that the plant developed energy t B E [kWh]:

VM LHVu E t bh t B  2778 . 0  t=0,..,T-1 (4)
Where bh  is the plant efficiency and 0.2778 is a conversion factor.

Energy from the flat plate collector

The useful thermal energy extracted from the water collector depends on the instantaneous incident solar irradiation, the plate area, and its efficiency [START_REF] El Fadar | Modelling and performance study of a continuous adsorption refrigeration system driven by parabolic trough solar collector[END_REF]). (7)

The hourly energy t p E that can be used in time interval for pumping water is given by:

t p t p Net t p PV t p WT t p CH E E E E     , , , t=0,..,T-1; (8)
The amount of pumped water is proportional to the energy used for this purpose, that is

ps gh t p E t w Q    t=0,..,T-1
Where  is the water density [kg m -3 ], g is the gravity constant acceleration [m s -2 ]; ps  is the pumping system efficiency and h is the height of pumping.

Energy flow exchange with the network:

The energy that is sent to the network is composed by the surplus produced by the wind turbine and the surplus produced by the PV module, i.e.,

t Net PV t Net WT t Net E E E , , ~  t=0,..,T-1 (10)
The energy that is taken from the network is given by

t p Net t e Net t h Net t Net E E E E , , , ˆ   t=0,.., T-1 (11)
The energy productions by the wind turbine and the PV module in each time interval can be used for different supply purposes: electrical demand, heating demand, water demand, sent to the battery or sold to the network. Thus, the following equations hold Instead, as regards biomass and flat collector plant, the produced energy can be less or equal to the available potential. In fact, biomass may not be used (also because if it is summer heating does not work and heating cannot be sent to the network), and water for heating passing through the plate collector may be stopped. This implies the following relations:

t B t h B E E  , t=0,..,T-1 (14) t FPC t h FPC E E  , t=0,..,T-1 (15)
Finally, t

Net PV E , and t Net WT E , are known because they are the surplus of electrical energy. That is,

           t b PV E t t PV E t e PV E t p PV E t PV E t Net PV E , , , , , 0 max , t=0,..,T-1 (16)            t b WT E t t WT E t e WT E t p WT E t WT E t Net WT E , , , , , 0 max , t=0,..,T-1 (17)

The battery storage state equation

The battery works as an inventory for the electrical energy that can, in this way, be stored. Specifically, a state equation for the battery storage can be formalized. That is,

t e CH t h CH t p CH t b PV E t b WT E t CB t CB        , , 1 t=0,…, T-1 (18)

The optimization problem

The decision variables of the optimization problem are The objective function (to be minimized) is characterized by the weighted sum of the deviation from the various demands., as well two terms to be maximized related to the energy sent to the storage system and the electrical network That is,

                                               1 1 1 1 2 1 1 , , , 2 1 1 , , ,
CB E Q gh CH E E E E CH E E E E CH E E E E E Z       t=0,..,T-1 (19)
Where  ,  ,  , and  are weighting factors, and C is the size of the battery. The problem is here solved using mathematical programming techniques through a commercial optimization package. Dynamic programming could also be used to reduce the overall problem complexity, decomposing it in sub-problems. In the case of absence of battery energy storage, since there are no state equations and available energy varies in each time interval, the optimization problem can be run at each time interval in a separated way. In the following, the optimization problem is solved for a specific case study, in which there is not the presence of the battery storage (thus, the variables related to the battery storage are known and equal to zero).

Application to a case study

The proposed DSS has been tested using the real data obtained from Capo Vado site, which is the windiest site in the region of Liguria, in Italy (Ouammi et al [2010]). The data of the First November 2008 have been used. They consist of the hourly wind speed, recorded at the height of 10m, and hourly solar irradiation (see figure 2). The optimization problem has been solved using the optimization tool Lingo (www.lindosystems.org). Figure 2: Hourly wind speed and solar radiation in the site of Capo Vado The wind model described by equations above has been applied to the specific case study, using the wind turbine G-3120 35 kW with the following parameters www.endurancewindpower.com:

v c = 3.5 [m/s], v r = 11[m/s], v f = 25 [m/s], P r = 35 [kW], hub H =30.5 [m], data H =10 [m], 0 z = 0.03 [m].
For the PV module, the features that has been used consist of: S pv =100 m 2 , η pv =0.11, η pc =0.86 and P f =0.9. 1234567891 0 1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0 2 1 2 2 2 3 2 Figure 3 shows the hourly energy produced by the wind turbine, as well as the hourly energy produced by the PV module. In fact, the figure shows that the energy range produced by the wind turbine is included between 14.3 kWh at 3:00 and a maximum value of 36.5 kWh at 16:00. However, for the solar module, the energy production reaches its maximum 4.5 kWh at 12:00. It seems that the energy production coming from the wind turbine is higher than the energy produced from the PV module. This fact is mainly due to the high wind speed in November and the low solar radiation. 1234567891 0 1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0 2 1 2 2 2 3 2 The optimal energy management that is addressed to satisfy the electrical energy needs of the household is displayed in Figure 4,The electrical energy demand reaches its higher hourly peak value of 2.4 kWh at 18:00 and a minimum of 1.3 kWh at 04:00. The hourly periods have been defined throughout the day: period A (1<t<8), period B (8≤t<17) and period C (17≤t≤24). During period A and C, the electrical energy needs were totally provided by the wind turbine owing to the absence of the solar radiation. During the period B, both the wind turbine and solar PV module provide sufficient energy to meet the hourly electrical energy demand of the household with a dominant participation of the solar PV module. 5 shows the contribution of biomass unit and the flat plate solar collector through the daily hours, we mention that these systems are responsible in addition to energy given by PV and wind turbine to provide a part of heating energy needs. In one hand, it can be shown that the energy delivered by the biomass system goes between a maximum that equals to 2 kWh and a minimum equal to 0.5 kWh. On the other hand, as regard the flat plate solar collector (FPSC), the energy produced from the sum goes directly to contribute in the satisfaction of the heating energy requirements, reaches a maximum of 1kWh at 12:00. We must notate that in this typical day, no wind and PV contribution is remarked for the supply of heat needs, the Biomass as well as the FPSC are the only one that furnish the heating needs of the household, As regard the water demand, its availability is depending on the working pumps which must use the electrical energy coming from the wind and PV systems in order to pump water. As displayed by Figure 6, three peaks are perfectly met during the hours of the day 6:00AM, 12:00PM and 19:00 PM, thus mainly using electrical energy from the wind turbine. By comparing energy produced by each system, it appears that the wind turbine provides the higher amount of energy. This behavior is mainly due to the high wind potential available in Capo Vado site compared with solar energy. In order to ensure the sustainability of the hybrid system, and addressing the mismatch between the intermittencies of wind and solar irradiation on one part and of demand in another part, the system presented in this paper integrates both: an internal storage system and a connection with the electrical grid, the main goal of implementing these two systems are: -the electricity generated by the wind and the solar modules exceed the total demand of the household, electricity will be "stored" at the battery and/or "sold" to the network.

-Once the battery is fully charged, the electricity excess will be sold directly to the electrical Network.

-Once the electricity generated by the wind, solar modules, biomass and FPSC is not sufficient, the deficit of electricity and/or the heating and/or pumping water system will be compensated by the electricity cumulated in the battery or purchased from the grid. The choice between these two electrical systems (battery and Network) will be guaranteed by the objective function and its constraints, thus by making the system more reliable as possible.

The cumulative storage battery level can be well seen from Figure 7, in fact, the battery has a large transitory regime until it reaches its higher storage value. This storage is effectuated during the day and at each hour, thus assuming that the battery was empty at t=0 which correspond to the initial time. In figure 8, the hourly electricity sold to the network is displayed. It can be shown that this transfer occurs during all the hours of the day, where the wind turbine is the one that send the excess of energy.

Conclusion

A DSS for real time energy management is here proposed to define the optimal energy flows in a building characterized by a mix of renewable resources (solar plate collector, PV, biomass, wind and battery storage) to satisfy different energy demands. The model is applied to the case of Capo Vado (Liguria Region) and optimal results to satisfy all the energy demands are found for a testing day in the month of November.

  The energy from wind turbine/PV that is sent to the battery [kWh] in time interval (t, t+1); t w Q : The amount of water pumped [m 3 /h] in time interval (t, t+1); t e CH : energy provided from the battery to the electricity [kWh] in time interval (t, t+1), t=0,..,T-1; t h CH : energy provided from the battery to the heating system [kWh] in time interval (t, t+1); t p CH : energy provided from the battery to the pumping [kWh] in time interval (t, t+1); t CB : the level of battery charge [kWh] at time instant t, t=0,..,T-1.

Figure 1 .

 1 Figure 1. The considered hybrid system 2.1 Energy from the wind turbine

Figure 3 :

 3 Figure 3: Hourly energy produced during the first November 2008.Figure3shows the hourly energy produced by the wind turbine, as well as the hourly energy produced by the PV module. In fact, the figure shows that the energy range produced by the wind turbine is included between 14.3 kWh at 3:00 and a maximum value of 36.5 kWh at 16:00. However, for the solar module, the energy production reaches its maximum 4.5 kWh at 12:00. It seems that the energy production coming from the wind turbine is higher than the energy produced from the PV module. This fact is mainly due to the high wind speed in November and the low solar radiation.

Figure 4 :

 4 Figure 4: Optimal electrical energy controlThe optimal energy management that is addressed to satisfy the electrical energy needs of the household is displayed in Figure4,The electrical energy demand reaches its higher hourly peak value of 2.4 kWh at 18:00 and a minimum of 1.3 kWh at 04:00. The hourly periods have been defined throughout the day: period A (1<t<8), period B (8≤t<17) and period C (17≤t≤24). During period A and C, the electrical energy needs were totally provided by the wind turbine owing to the absence of the solar radiation. During the period B, both the wind turbine and solar PV module provide sufficient energy to meet the hourly electrical energy demand of the household with a dominant participation of the solar PV module.

Figure 5 :

 5 Figure5: Optimal heating energy control Figure5shows the contribution of biomass unit and the flat plate solar collector through the daily hours, we mention that these systems are responsible in addition to energy given by PV and wind turbine to provide a part of

Figure 6 :

 6 Figure 6: Optimal control of the water demand

Figure 7 :

 7 Figure 7: wind and solar energy sent to the battery

Figure 8 :

 8 Figure 8: energy sold to the network

  The hourly energy that can be used in time interval for heating, t

	That is, E , is expressed by t=0,..,T-1 E that can be used in time interval is expressed by: t=0,..,T-1 t h t h Net t h B CH E E    , , The hourly electrical energy t t G A E t fpc fpc t FPC   .  t h FPC t h PV t h WT t h E E E E    , , , e Where h t e t e Net t e PV t e WT t e CH E E E E     , , , t=0,..,T-1;	(5) (6)

fpc  is the efficiency of the solar flat plate collector, fpc A [m 2 ] is the area and t G [kW/m 2 ] is the solar irradiation. 2.5 Produced thermal and electrical energy H. Dagdougui et al. / A dynamic optimization model for smart micro-grid: integration of a mix of renewable resources for a green building 4


Veronika Lux-Pogodalla
email: veronika.lux@atilf.fr

Alain Polguère
email: alain.polguere@atilf.fr

Construction of a French Lexical Network: Methodological Issues

We present a new lexicographic enterprise that aims at producing a French Lexical Network or FLN. We begin by introducing the project as such and then proceed with a characterization of the FLN: the FLN as a generic lexical model, its network structure and the different types of lexical entities it models. Finally, we focus on two aspects of our lexicographic methodology: the incremental identification of the FLN's wordlist and our editing tool.

The French Lexical Network project

We present a lexicographic project that has just been officially launched (early 2011) and whose aim is to build a new type of lexical resource called French Lexical Network, hereafter FLN. 1 Though the construction of the FLN is conceived as a long-term enterprise, we focus here on the first three-year phase, i.e. the tasks that have actually been planned and funded in the context of a more global R&D project called RELIEF. For lack of space and in order to concentrate on the very specific topic of lexical resources' design and construction, we will ignore the application/valorisation aspects of RELIEF and exclusively deal with the FLN itself. We are fully aware of the fact that, by presenting a lexical resource that is only emerging from the drawing board, we have no tangible "results" to offer as yet. However, we believe that the FLN project is sufficiently specified, both in terms of design of the lexical resource and of lexicographic methodology, to be of interest for the research community-not to mention the importance there is for the FLN team to benefit from early feedback from this community. Additionally, it will appear clearly in what follows that the FLN is not a project that started from scratch, but a project that directly builds on previous research and lexicographic work performed over the last two decades. The structure of the remainder of the paper is as follows. The main characteristics of the FLN are presented in section 2.: the FLN as a generic lexical model, its network structure and the different types of lexical entities it describes. In section 3., we focus on two aspects of our lexicographic methodology: the incremental identification of the FLN's wordlist and our editing tool. Before we begin, let's mention that a lexicographic team of around 15 persons is being put together for the initial three-year phase of the FLN project. Lexicographic strategies embedded in our theoretical and methological framework of reference-the Explanatory Combinatorial Lexicology [START_REF] Mel'čuk | Introduction à la lexicologie explicative et combinatoire[END_REF][START_REF] Mel'čuk | Explanatory Combinatorial Dictionary[END_REF]-will serve to extract linguistic information from corpora. However, 1 The French name of the targeted lexical resource is Réseau Lexical du Franc ¸ais or RLF we will also make extensive use of the Trésor de la Langue Franc ¸aise informatisé [START_REF] Dendien | Le Trésor de la Langue Franc ¸aise informatisé: un exemple d'informatisation d'un dictionnaire de langue de référence[END_REF], hereafter TLFi,2 as a mother lexical database from which we will extract lexicographic information to be reinterpreted and exploited within the FLN.

Main characteristics of the FLN

This section offers a three-step characterization of the global structure of the FLN: the FLN as a generic lexical model (2.1.), the lexical network structure of the FLN (2.2.) and the various types of lexical entities this network connects (2.3.).

Generic lexical model

In a nutshell, the FLN is designed to belong to the -Net family of lexical resources, such as WordNet [START_REF] Fellbaum | WordNet: An Electronic Lexical Database[END_REF] and FrameNet [START_REF] Baker | The Structure of the FrameNet Database[END_REF]Ruppenhofer et al., 2010). In addition to its network structure, that will be examined in section 2.2., it shares two main characteristics with WordNet and FrameNet: 1. it is not a dictionary, i.e. it is not a "textual," linear model of the lexicon;

2. it is nevertheless built in a lexicographic way, i.e. manually by a lexicographic team.

Like WordNet and FrameNet, the FLN has been from the onset conceived of as a generic, general purpose lexical database. However, it is possible to derive a wider range of lexical resources from it: lexicons for NLP systems, fullfledged dictionary entries (similar to those of standard dictionaries) and on-line lexical resources for language teaching/learning. For this reason, it is not focusing on a limited set of specific properties of lexical units (such as semantic hierarchical organization of synsets for WordNet or frames controlling the semantics-syntax interface for FrameNet), but adopts a global view of all lexical properties, very much like dictionaries would do: lexicographic definition, grammatical features, syntactic combinatorics (roughly, subcategorization frames), lexical combinatorics and derivational links. In that respect, the FLN is equivalent to a virtual dictionary [START_REF] Selva | Vers une deuxième génération de dictionnaires électroniques[END_REF] or, rather, to virtual dictionaries of various macro-and microstructures that can automatically be generated from it.

Lexical network structure

The FLN's architecture is similar to a lexical system, as presented in [START_REF] Polguère | Lexical systems: graph models of natural language lexicons[END_REF]: a huge network of lexical units connected by a broad range of lexical links encoding semantic or combinatorial lexical relations. The bulk of the network structuring is carried out by means of the system of standard lexical functions [START_REF] Mel'čuk | Lexical Functions: A Tool for the Description of Lexical Relations in the Lexicon[END_REF], that allows for a rigorous encoding of lexical paradigmatic links (synonymy, antonymy, conversivity, actant names, etc.) as well as syntagmatic links (collocations controlled by lexical units-their typical intensifiers, support verbs, etc.). Lexical functions have previously been used in the design of other lexical databases [START_REF] Fontenelle | Turning a bilingual dictionary into a lexical-semantic database[END_REF][START_REF] Selva | Vers une deuxième génération de dictionnaires électroniques[END_REF]; the FLN is drawing mainly from previous work done on the DiCo lexical database [START_REF] Steinlin | Compiling a "classical" explanatory combinatorial lexicographic description into a relational database[END_REF] in making use of a double encoding of lexical links:

1. formulas based on the formal language of lexical function relations [START_REF] Kahane | Formal Foundation of Lexical Functions[END_REF];

2. "popularization" of these formulas in the form of paraphrases (in controlled natural language) of the corresponding paradigmatic or syntagmatic link.

For instance, following this approach, the paradigmatic link holding between KILL V [These mushrooms can kill you!] and LETHAL is to be encoded as follows in the lexicographic article for this sense of KILL V (popularization comes first, followed by the lexical function formula):3

[X] that can ∼ Able 1 lethal

The formal encoding allows for various computations on the lexical graph and the popularization allows for the generation of general public lexicographic descriptions (dictionary articles) from the lexical database. 4Beside lexical-functional links, the FLN graph will also encode embedding of semantemes (lexical senses) through its formal definitions-see section 3.2.2. below. The main aim of the FLN network structuring is to build a model of French lexical knowledge that is truly generic and independent of any specific textual (dictionary-like) or hierarchical (ontology-like) organization. It can also be expected that the chosen model, because of its non-textual nature, will be closer to what is generally believed to be the network-like structure of the mental lexicon (Aitchison,2.3. Lexical entities that are nodes of the FLN graph The FLN will be stored as an SQL database, which will implement its network structure as a set of connections between lexical entities of different types. Central to the lexicographic description are lexical units proper, which are of two kinds: Only lexemes and idioms are considered in the FLN as fullfledged lexical units, and they are the actual units of lexicographic description. Vocables-polysemic words-are modelled as sets of lexical units connected in the graph by a relation of copolysemy. The FLN will put strong emphasis on phraseology, i.e. on the set phrases of the language, known as phrasemes. Following [START_REF] Mel'čuk | Phrasemes in Language and Phraseology in Linguistics[END_REF], three main types of phrasemes are being considered: (full) idioms, linguistic clichés and collocations.

Because they are lexical units, as much as lexemes are, idioms will be described by "normal" lexicographic articles, and not embedded in the article of one of the lexemes they formally contain. For instance, COUP DE SOLEIL is not to be described as embedded lexical entity in the article for COUP I.1, as it is presently the case in standard language French dictionaries such as Petit Robert (Rey-Debove and Rey, 2010).

Linguistic clichés, such as Fr. Après vous ! 'Go ahead!' (lit. 'After you') are the second type of phrasemes that will be accounted for by lexicographic articles. However, because they are not actual lexical units, clichés will not be considered as "entries" in the database and will receive a somewhat simplified description: no actual lexicographic definition (which will be replaced with the specification of the communicational goals of the speaker) and no indication of combinatorial properties.

As for collocations-compositional though phraseological expressions [START_REF] Hausmann | Un dictionnaire des collocations est-il possible ? Travaux de littérature et de linguistique de l[END_REF][START_REF] Benson | The BBI Dictionary of English Word Combinations[END_REF]-, they will be accounted for in the article for their base by means of syntagmatic lexical functions, following the approach taken in the DiCo (already mentioned in section 2.2.) and other related lexicographic models.

It can be noted that the lexicological principles adopted for the FLN are very much the same as those of the DiCo project, except for two major differences:

1. Each lexical unit is to be semantically described by a complete and formalized lexicographic definitionwhereas the DiCo only provides a description of the actancial structure of the unit together with a semantic label [START_REF] Polguère | Étiquetage sémantique des lexies dans la base de données DiCo[END_REF]Polguère, To appear).

2. The data structure of the FLN is a true lexical system, i.e. a network of semantic and combinatorial connections between lexical units. The DiCo's lexical links are in reality connecting lexical units to string of characters (lexical forms), pretty much like any standard dictionary.7

By reifying the target of lexical links, the FLN will play in the same "formal" league as WordNet or FrameNetthough its initial vocabulary coverage will of course be very small in comparison (see section 3.1. below, on the FLN's coverage).

Lexicographic methodology

This section deals with two methodological aspects of the project that we consider crucial and to which particular attention has been paid: the incremental identification of the FLN's "wordlist" (3.1.) and the writing of FLN articles (3.2.3.).

3.1. The FLN's lexical coverage 3.1.1. Incremental identification of the "wordlist"

In the long run, the FLN should cover the bulk of basic contemporary French. This is a gigantic task, that can only be handled through a series of carefully planned successive efforts. As mentioned earlier, this paper deals exclusively with the initial three-year phase. At the end of this first phase, the FLN should possess a "wordlist"-though the term wordlist may not be fully relevant in the specific case of a lexical network-of at least 10,000 vocables. 8 How are these vocables selected among the 70 to 80,000 vocables described in a standard commercial dictionary such as Nouveau Petit Robert, idioms included?

The FLN is not designed as a dictionary and, therefore, the process of selecting and building the wordlist can be very different from the selection process implemented by lexicographers of "traditional" dictionaries, such as the TLF, our dictionary of reference (see end of section 1. above).

Because of publishing constraints-need for regular releasing of fully completed volumes-, the TLF lexicographers had to first define a whole wordlist, proceeding afterwards through it in strict alphabetical order: vocables starting with the letter A being described first, those with letter B second, etc. Contrary to this, our progression will not be alphabetical. It will proceed through series of important lexical fields of the language: vocables whose basic lexical unit belong to the semantic field of feelings, of relationships, of animals, of tools, etc. This allows us to start with an initial priming wordlist-Fr. nomenclature d'amorc ¸age-that will constantly grow during the project, following a logic that will be detailed shortly.

The priming wordlist

How do we determine the priming wordlist that will be the "seed" from which the whole FLN wordlist will grow in the years to come? In the beginning, priority is given to the most basic, common French vocables. To identify them, we made use of four types of sources:

1. well-known lists of "basic French" developed mainly for applications in language teaching; essentially: the 3,500 vocables of the Franc ¸ais fondamental [START_REF] Gougenheim | L'élaboration du franc ¸ais fondamental[END_REF] Through a cross-checking process,10 we have identified a priming wordlist of 3,739 vocables, which we believe will induce the description of the basic, minimal set of vocables any speaker of the language, any NLP system, etc., should master.

The number of 3,739 may seem arbitrary, and to some extent it is. This, however, is inconsequential for three reasons. First, it can be noted that most studies on vocabulary thresholds for basic language proficiency conclude to vo-cabulary sizes that range from 3,000 "word families" 11 for basic use to 9 to 10,000 for advanced proficiency [START_REF] Hirsh | What Vocabulary Size Is Needed to Read Unsimplified Texts for Pleasure? Reading in a Foreign Language[END_REF][START_REF] Nation | How large a vocabulary is needed for reading and listening? The Canadian Modern Language Review[END_REF]. Our 3,739 vocables priming wordlist is therefore in the lower bracket, but still in the realm of what can be considered as a reasonable, basic vocabulary. Second, what matters most is that the vocables we have selected do all belong to basic French and none are peripheral elements of the French vocabulary. Third, it is irrelevant whether one, or two, or 36 vocables have been omitted whose inclusion in the priming wordlist vocabulary would be justified. If a vocable is "missing" for whatever reason, and if it truly belongs to basic French, the induction process that we are now about to describe will catch up with it and have it included in the induced wordlist-Fr. nomenclature induite.

The induced wordlist

There are three different ways a vocable that is not present in the priming wordlist can be induced from it: 1) its basic lexical unit is a "close" semantic derivative (nominalization, verbalization, etc.) of the basic lexical unit of a priming vocable, 2) it is a very common idiom formally made up of lexemes of the priming wordlist or 3) its various senses are the target of a significant number of lexical links originating from the lexicographic description of units of the priming wordlist. 1) Induced close semantic derivatives A lexical unit L 2 is a semantic derivative of a lexical unit L 1 if it is the target of a paradigmatic lexical-functional link originating from L 1 . The semantic derivation relation between these two units may or may not be marked morphologically.

We use the eleven following paradigmatic lexicalfunctional links to identify what we term the close semantic derivatives of a given lexical unit L. Notice that the eleven above-mentioned lexical functions are used here in their "narrow sense," described in the glosses that accompany them. For instance, strictly speaking, VICTIM [of a murder] is a valid S 2 for MURDER N [by X of Y], but it should not be considered as being a close semantic derivative because its meaning is much vaguer than 'Y of a murder' (*murderee).

It is good practice in Explanatory Combinatorial Lexicography to describe a vocable V together with all vocables whose basic lexical unit (basic sense) is a close semantic derivative of the basic lexical unit of V. For instance, MURDER N should necessarily be lexicographically described together with MURDER V , MURDEROUS, MUR-DERER and MURDERESS. In order to adhere to Explanatory Combinatorial methodology, we consider as induced vocables all vocables whose basic lexical unit is a close semantic derivative of the basic lexical unit of a priming vocable. For instance, though PR ÉVISION 'prediction' is not in our priming wordlist, it is included into the induced wordlist as it is a close semantic derivative of the priming vocable PR ÉVOIR 'predict.' Notice however that, at this stage, only close semantic derivatives that are commonly used and do not belong to specialized vocabularies will be induced. For instance, HASE 'femal hare' is a close semantic derivative of LI ÈVRE '(male) hare,' which belongs to the priming wordlist, but it will not be directly induced from it because of its almost technical nature.

2) Induced idioms The priming wordlist is made up of lexemic vocables. Any common idiom that is formally made up of lexemes that belong to the priming wordlist will be systematically included into the induced wordlist. For instance, as COUP, DE and SOLEIL (see section 2.3. above) all belong to the priming wordlist, COUP DE SOLEIL 'sunburn' is identified as induced vocable and added to the lexicographic team's in-tray.

3) High degree nodes of the graph In the process of describing vocables of the priming wordlist, lexicographers will be lead to introduce "on the fly" many new nodes in the FLN graph. They correspond to lexical units that are the target of links originating from priming lexical units. Two main types of links have to be considered. Firstly, any lexical unit used in a lexicographic definition for a priming lexical unit is necessarily the target of a lexical link (of semantic inclusion). If this target is itself a priming lexical unit, nothing needs to be done. If it is not, a minimal entry for it is generated on the fly in order to make the link hold 12 (on FLNs' definitions, see section 3.2.2. below). For instance, if ASTRE-a very basic but not so com-mon term roughly equivalent to 'celestial body'-is used as a generic component in the definition of the lexeme SOLEIL 'sun,' then ASTRE will be included in the FLN graph, with minimal information (mainly, its part of speech and some illustrative linguistic examples). Secondly, any lexical unit that is the target of a lexicalfunctional link originating from the description of a priming lexical unit also has to be inserted on the fly in the FLN graph. For instance, the adjectival unit RETENTIS-SANT 'resounding' will be inserted in the graph though it is not among the 3,739 units of the priming wordlist because COUP I.1 'knock' is a priming lexical unit and RETENTIS-SANT is one possible Magn (= intensifier) for it. 13 As a result of the strategy of on-the-fly creation of entries for targeted lexical units, the FLN graph will gradually incorporate a large number of roughly sketched nodes that did not belong to the priming wordlist. A statistical analysis of the graph will regularly be performed in order to identify a list of top non-priming nodes of the graph that possess a high degree of connectivity. These nodes define the next batch of vocables to be inserted in the induced wordlist.

Figure 1 visualizes the wordlist expansion via insertion of idioms, close semantic derivatives and targeted units. As we see, starting from the initial priming wordlist, the FLN will induce its own expansion according to a very simple logic: lexical units that are often referred to by units of the priming wordlist are "important" units, on which lexicographic work should focus. This strategy can be applied indefinitely as a guide to the expansion of the FLN.

Writing of FLN's articles 3.2.1. In lexicography, size matters

Work previously done on the DiCo database and on other extremely rich and formalized lexicographic models based on Explanatory Combinatorial Lexicology [START_REF] Mel'čuk | Dictionnaire explicatif et combinatoire du franc ¸ais contemporain[END_REF][START_REF] Mel'čuk | Dictionnaire explicatif et combinatoire du franc ¸ais contemporain[END_REF][START_REF] Mel'čuk | Dictionnaire explicatif et combinatoire du franc ¸ais contemporain[END_REF][START_REF] Mel'čuk | Dictionnaire explicatif et combinatoire du franc ¸ais contemporain[END_REF] has shown that even skilled lexicographers fail to ensure the coherence of such lexical models when they grow to more than a thousand entries or so.

If one wants to use this kind of approach to embark on a major lexicographic project, a rich tailor-made editing environment is required. FLN articles have to comply to a well-specified structure that could be encoded, in theory, as an XML schema, and 13 More precisely, it corresponds to the semi-standard lexical function in respect to noise Magn, or Magnnoise.

enforced through the use of an XML editor. However, there are two aspects of the FLN project that make it impossible to rely on such basic lexicographic tools. Firstly, building the FLN is a true, large-scale lexicographic enterprise involving the coordinated work of an organized lexicographic team. There is therefore a need to possess an editor that, on top of ensuring the control of the formal validity of the description, will implement a lexicographic production line, with its various tasks (drafting, development, completion with corpus data, revision cycles, etc.) and their logical organization-a workflow management tool system. Secondly, what really makes the editing of an FLN article complex is the fact that the information it contains has to be stored not as text, but as a database of connected entities forming a lexical graph. We believe that only this type of data structure will ultimately allow us to perform efficient consistency checks and other logical operations on our model of the lexicon. We are particularly interested in the possibility of using the graph structure of the FLN and formal properties of lexical-functional links to implement semi-automatic drafting of vocables based on potential analogies with already existing descriptions-on this, see Jousse (2010, p. 236-257). Off-the-shelf professional dictionary production softwares such as TLex14 (de Schryver and de Pauw, 2007) do exist and are used to build major commercial dictionaries. In our case, we chose to work in close collaboration with MVS Publishing Solutions,15 our partner in the RELIEF project (see section 1.), to tune their Dixit editor for our specific needs. This editor is a component of a software suite mainly used for the publication of daily newspapers. It controls the writing process of newspaper articles (structuring of the article, handling of its editorial cycle and SQL storage of textual as well as non-textual information), data management and automatic generation of printed articles based on predefined layout rules. Thus, it already contains all functionalities one needs in order to perform the writing and, even, publication/dissemination of lexicographic articles. In the remainder of this section, we will first describe the FLN microstructure the editor has to handle (3.2.2.), then explain the main features of the editor (3.2.3.).

Structure of a lexicographic article

The structure of an FLN article is very similar to that of a DiCo record [START_REF] Lareau | A practical guide to writing DiCo entries[END_REF][START_REF] Jousse | Le DiCo et sa version DiCouèbe[END_REF], and an SQL export of the DiCo data is actually being used for tuning the FLN lexicographic editor. As can be seen in Figure 2 below, with the article for ADMIRER I 'to admire [someone for something],' an FLN article is divided into six main sections, of which only the second one-Definition-is absent from DiCo records and will therefore be presented in some detail here.

1. Grammatical features This section lists features encoding combinatorial properties of the keyword (register, part of speech, inflectional restrictions, etc.).

Definition

In the FLN, each full lexical unit is to be semantically described by means of a paraphrastic definition (which was not the case in the DiCo). Each definition is made up of two components:

a. The definiendum is a description of the actancial structure of the keyword. b. The definiens (definition proper) is the analytical paraphrase of the keyword's meaning. Prototypically, a definiens is mainly made up of a central component (CC) and one or more peripherical components (PC). Lexicographers annotate the text of the definiens so as to make its internal structure explicite. For example, the definiens in Figure 2 below is encoded in the background as follows: 16

<DEFINIENS label="apprécier"> <CC>L'individu X apprécie Y pour Z</CC> <PC role="intensity"> beaucoup</PC> <PC role="cause"> du fait des qualités exceptionnelles de Z</PC> </DEFINIENS> As indicated in 3.1.3., each lexical item occurring in the definition is connected by a semantic inclusion link to a specific lexical unit-whether priming, induced or pending description-, whose own definition, if it exists, will be subjected to the same formal treatment. Of course, such strategy will make the process of writing a lexicographic definition very slow and, in some respects, tedious. It should be noted, however, that it has the positive effect of forcing lexicographers to proceed very selectively and with economy in writing lexicographic definitions, thus ensuring the production of definitions of greater clarity 17 -see, for instance, the systematic use of a basic defining vocabulary in the definitions of the Longman dictionary (Summers, 2005).

3. Government pattern This section describes how the keyword's semantic actants can be expressed as its syntactic dependents. A database of French government patterns will be included in the FLN data structure and valency tables (roughly, subcategorization frames) appearing in a lexicographic article will ultimately be directly imported from this base rather than manually typed by lexicographers.

Lexical functions

This section is the core of the lexical description, as explained in 2.2. Lexical links implemented here will be the main structuring elements 16 For more information on this approach to formally structuring lexicographic definitions, see [START_REF] Barque | From the Definitions of the Trésor de la Langue Franc ¸aise To a Semantic Database of the French Language[END_REF]. 17 The rather wordy definition for ADMIRER I in the TLF is Considérer quelqu'un ou quelque chose avec un sentiment d'étonnement mêlé de plaisir exalté et d'approbation, le plus souvent motivé par la supériorité qu'on lui reconnaît dans divers domaines de la vie intellectuelle, esthétique, morale, etc. 'To consider someone or something with a feeling of mixed exalted pleasure and approbation, usually motivated by the superiority one acknowledges to him/it in various aspects of life-intellectual, esthetic, moral, etc.' of the FLN lexical graph. For lack of space, we cannot enter into the details of the encoding of paradigmatic and syntagmatic links by means of lexical functions. This topic is largely dealt with in the literature on Explanatory Combinatorial Lexicology cited in this paper.

5.

Examples This section of FLN articles will be much more structured than what can be seen in Figure 2, where only examples imported from the DiCo appear.

In an actual FLN article, there will be several types of lexicographic examples, mainly: citations from texts of various genres with exact references-extracted from Frantext 18 and other ATILF in-house corporaand hand-crafted adaptations of corpus/Internet data.

6. Phraseology This last section lists idioms or linguistic clichés that formally contain the keyword. Each enumerated phraseme is linked to the corresponding FLN article.

Designing a lexicographic editor

Recall that the unit of lexicographic description in the FLN is the lexical unit: lexeme ("word" taken in one specific sense) or idiom. Though other lexical entities-such as linguistic clichés (cf. 2.3. above)-may be described by means of lexicographic articles, the editor is essentially providing an interface for lexicographers to describe properties of lexical units. The lexicographic editor for FLN is currently being prototyped by MVS Publishing Solutions using their Dixit general purpose editor. Figure 2 below is a sample screendump of the editor's interface in its present, very preliminary state. It shows the ADMIRER I entry, based on DiCo data to which a full-fledged lexicographic definition has been added. The purpose of this figure is mainly for the reader to visualize better the type of lexicographic data we are dealing with. The editing interface helps lexicographers produce descriptions that comply to the microstructure presented above. Practically, their task is closer to filling-in a very complex and structured form than to performing free writing, which is precisely what is required for lexicographic tasks. Moreover, in each section, the editor provides assistance to control compliance to particular constraints on content, ultimately ensuring that the entry is built as a valid subgraph of the global FLN. Depending on the constraints, the level and type of assistance will vary in each section, for instance:

• Normalized content can be directly selected from menus. Text items selected from menus are noneditable text in the article. (They can only be modified through menu selection.)

• Normalized content can also be selected via a form providing filtering features. This is for instance the case with the Lexical functions section: there are hundreds of potential lexical function formulas, too many for a single menu. Lexicographers can either indicate some features of the lexical function they are looking

Conclusion

As mentioned at the very beginning of this paper, we are presenting a new lexicographic project and it is too early for us, at the time of writing, to be able to draw any conclusion from our theoretical and methodological choices. However, we believe the content, structure and methodological design of the FLN to be original enough to generate interest for anyone concerned with the construction and availability of multi-purpose lexical resources. Of particular relevance is the fact that the FLN is designed as a truly generic database. It targets NLP exploitation-that imposes very strong formal constraints on lexical data-as well as pedagogical exploitation-that shows zero tolerance to error in the modeling of linguistic rules. Note that the FLN will be made available on the CNRTL website19 in the course of its growth, both as a source SQL database and via a web-based interface for manual consultation. It is also our intention to later explore the possibility to generate LMF20 compatible exports of FLN data.

Figure 1 :

 1 Figure 1: Self induced expansion of the wordlist

Figure 2 :

 2 Figure 2: DiCo's data for ADMIRER I 'to admire [someone for something]' processed with the FLN editor

  ACTRESS, DOG → BITCH; 4. V 0 : verbal conversion of L, e.g. KNOCK N → KNOCK V ; 5. S 0 : nominal conversion of L, e.g. KNOCK V → KNOCK N ; 6. Adj 0 : adjectival conversion of L, e.g. COAST N → Able i : adjectives meaning 'that has the ability to be the i th actant of L', e.g. LOVE V → LOVABLE [= Able 2 ]. 11. strict Mult: collective nouns that do include in their definition the meaning of L, e.g. LEAF → FOLIAGEbut SCHOOL [of fish, shrimps. . . ] is not induced directly from FISH, as it is too vague.

	COASTAL;
	7. Adv 0 : adverbial conversion of L, e.g. SLOW Adj →
	SLOWLY;
	8. S i : nouns meaning 'i th actant of L', e.g. DRIVE V →

1. Syn: exact synonyms of L, e.g. MOVIE → FILM N ; 2. Anti: exact antonyms of L, e.g. LEGAL → ILLEGAL; 3. of opposite sex Syn ∩ : quasi-synonym (more specifically, intersecting synonym) of L that denotes the same individual/animal as L but of the opposite sex, e.g. ACTOR → DRIVER [= S 1 ]; 9. A i : adjectives meaning 'that is the i th actant of L', e.g. HUNGER → HUNGRY [= A 1 ];

11 In P. Nation's terminology, a word family is a word morphological base form plus all its associated inflectional variants and regular morphological derivations.

10.

TLF stands for the original "paper" dictionary and TLFi for its electronic on-line version. The TLFi's URL is: http://atilf.atilf.fr/tlf.htm.

X stands here for the first actant of the keyword (KILLV = 'X kills Y') and ∼ for the keyword itself.

For a general public dictionary (manually) generated from the DiCo database, see the Lexique actif du franc ¸ais[START_REF] Mel | Lexique actif du franc ¸ais[END_REF].2003).The main originality of the FLN in terms of structuring, when compared to databases of the -Net family, is that it proposes a multi-dimensional graph structure for all standard paradigmatic and syntagmatic links; it does not organize lexical information "through the eyes" of just a few selected links, such as hyperonymy or synonymy. To the best our knowledge, such structure has yet to be implemented, at least for the French language.

He got a knock on his head when he fell.

The burglar stroke him a blow on his head.

Of course, a lexical link in the DiCo can specify the actual lexical sense that is the target of the link (coup#I.1 instead of just coup). This, however, is only transparent for the human user of the database and no actual connection is implemented at the level of the data structure.

In comparison, the DiCo-which covers a "sample" rather than a "core" French vocabulary-has a wordlist of 395 finalized (status 0) and 145 prefinalized (status 1) vocables, for a total of 1,127 word senses. The DiCo is accessible on-line in two forms: 1) the DiCouèbe interface to DiCo's SQL tables (http: //olst.ling.umontreal.ca/dicouebe) and 2) the Di-CoPop dictionary pages automatically generated from the SQL tables (http://olst.ling.umontreal.ca/dicopop).

This list, compiled at the Institut National de la Langue Franc ¸aise (INaLF), is available from the Éduscol French government website: http://eduscol.education.fr/.

 10 For instance, the Robert Benjamin's wordlist contains many vocables that are mainly relevant in the context of primary school education and by no means belong to the minimal core of French vocabulary-QUADRILAT ÈRE 'quadrilateralN', SOR-CIER/SORCI ÈRE 'sorcerer'/'sorceress,' etc. Such vocables are not to be included in the priming wordlist.

Of course, it can also be the case that this unit, though not priming, is already present in the lexical graph as a result of an earlier on-the-fly generation.

http://tshwanedje.com/

http://www.mvs.fr/

http://www.cnrtl.fr/

Lexical Markup Framework,ISO-24613:2008 (Francopoulo

Acknowledgements

Many thanks to Sébastien Haton, Jasmina Milićević, Dorota Sikora and two reviewers for WoLeR 2011 for their comments on a preliminary version of this paper. We are very grateful to Pascale Lefranc ¸ois (Université de Montréal) and Ophélie Tremblay (Université du Québec à Montréal) for giving us access to their research material, that helped us greatly in the construction of the FLN priming wordlist; we additionally thank Caroline Bégin (MELS) and Hélène Cajolet-Laganière (Université de Sherbrooke) for authorizing the dissemination of the information contained in Lefranc ¸ois et al. (2011). The RELIEF project is supported by a grant from the Agence de Mobilisation Économique de Lorraine (AMEL) and Fonds Européen de Développement Régional (FEDER).