Bin Wang

Denis Duhamel
email: denis.duhamel@enpc.fr

On the design and optimization of acoustic network resonators for tire/road noise reduction

Keywords: Acoustic network resonator, End correction, Resonant frequency, Optimization

In this work we propose a numerical method for the calculation of resonant frequencies of network resonators and we also present an optimization method based on genetic algorithms to get targeted resonant frequencies of the network resonators. We can optimize parameters of the network structure such as junction types and end positions. Experiments are conducted on optimized wooden network resonators to validate the method. Good agreement is found between the measured and targeted resonant frequencies. Applications to tire/road noise are considered.

Introduction

Tire treads and road textures in the contact zones between tires and roads can be considered as acoustic network resonators. Consequently, the acoustic fields around the tire/road systems are influenced by network resonances. These network resonances in the contact zone in Fig. 1 are seen as one of the noise enhancement mechanisms in [START_REF] Sandberg | Tyre/road noise reference book[END_REF]. Since the network resonators in the contact zone have large influence on the acoustic fields around their resonant frequencies, the network resonators should be investigated in detail. First studies of some simple acoustic resonators are reviewed as follows. Besides porous materials and perforated panels, narrow quarter-wave tube resonators are also widely used for the sound absorption in a wall or panel for a narrow frequency band based on the resonance of air inside the tube and the viscous shear and thermal conductivity losses on the tube walls. The model by Zwikker and Kosten [START_REF] Zwikker | Sound Absorbing Materials[END_REF] for wave propagation in cylindrical tubes included the viscosity and thermal conductivity. Tijdeman [START_REF] Tijdeman | On the propagation of sound waves in cylindrical tubes[END_REF] proved that this model is complete and accurate for both narrow and wide tubes. Eerden [START_REF] Van Der Eerden | Noise reduction with coupled prismatic tubes[END_REF] studied the influence of the viscous and thermal conductivity losses on the absorption coefficient and concluded that the viscothermal effects cannot be neglected if the resonators are used for sound absorption because they result in energy being dissipated and the effective speed of sound inside the tube can be considerably reduced. Around the resonant frequencies, we can see a maximum sound absorption. The theory and applications of quarter-wave resonators are summarized in [START_REF] Field | Theory and applications of quarter-wave resonators: A prelude to their use for attenuating noise entering buildings through ventilation openings[END_REF].

The quarter-wave tube has an open and a closed end, but resonators with two open ends can also be used for the sound absorption, especially for the case where air needs to be transported through walls or one needs to see through the wall. Eerden [START_REF] Van Der Eerden | Noise reduction with coupled prismatic tubes[END_REF] studied this case, and concluded that at low frequencies (f < 2000Hz) the waves propagating in the resonator are not absorbed at the end but are reflected back into the resonator due to the mass reactance at the free end. For higher frequencies (2000 -10000Hz) the waves are absorbed due to radiation into infinity. In order to create broadband sound absorption, coupled tube resonators with different cross-sectional areas and lengths can be applied. The mechanism for the broadband absorption is that the sound energy is dissipated by the viscothermal effects and the incident waves are cancelled due to the broadband resonance of air in the coupled resonators.

Helmholtz resonators (HRs) are also used to control the noise inside enclosures in many studies. Helmholtz resonators can be considered as a mass-spring system. The spring stiffness is represented by the volume of air and the mass is given by the small column of vibrating air in a perforation of the panel. The energy can be dissipated by the vibrating air and the porous material placed in the volume. See [START_REF] Fahy | A note on the interaction between a helmholtz resonator and an acoustic mode of an enclosure[END_REF][START_REF] Slaton | Acoustic power measurements of a damped aeroacoustically driven resonatora)[END_REF][START_REF] Cummings | The effects of a resonator array on the sound field in a cavity[END_REF][START_REF] Doria | Control of acoustic vibrations of an enclosure by means of multiple resonators[END_REF][START_REF] Inácio | Design of duct cross sectional areas in bass-trapping resonators for control rooms[END_REF] for different applications of these Helmholtz resonators to noise reduction. More specifically T-shaped acoustic resonators can be seen in many studies for noise control in small enclosures, see for instance [START_REF] Merkli | Acoustic resonance frequencies for a t-tube[END_REF][START_REF] Li | On the design of long t-shaped acoustic resonators[END_REF][START_REF] Li | Vibroacoustic behavior and noise control studies ofadvanced composite structures[END_REF][START_REF] Yu | Acoustic resonators for noise control in enclosures: modelling, design and optimization[END_REF][START_REF] Li | Noise control of mock-scale chambercore payload fairing using integrated acoustic resonators[END_REF][START_REF] Lane | Fairing noise control using tubeshaped resonators[END_REF] for models and experimental results on these resonators.

If we are interested more specifically in tire noise, today the noise due to the vibrations of a rolling tire can be calculated with convincing accuracy. However, air pumping is not understood very well. In [START_REF] Hayden | Roadside noise from the interaction of a rolling tire with the road surface[END_REF] Hayden described the air movement in the contact zone between a rolling tire and a road. Air is squeezed out when the treads at the entrance of the contact zone are compressed on the road surface, and flows into the voids when the treads lift up from the road surface. Daffayet et al. [START_REF] Deffayet | Air-pumping phenomena in road cavities[END_REF] measured the pressure in cylindrical cavities over which a smooth tire rolled. They assumed that the noise is generated by opening and closing the cavities in the contact zone. Ronneberger [START_REF] Ronneberger | Experimentelle und theoretische untersuchungen spezieller mechanismen der rollgeräusche[END_REF] thought that air was displaced by the changing gaps between the tire and road surfaces, because the treads are deformed by road roughness. These sources are located in the contact zone between the tire and the road and the sound is modified by the horn effect.

Horn effect is an essential noise enhancement mechanism. The tire/road system can be seen as a horn-like structure. The surfaces of the tire and the road constitute horns in front of and behind the contact zone. The noise generated in the contact zone is amplified by the multiple reflections between the tire surface and the road surface which are acoustically reflecting surfaces. The amplification of the horn effect reaches up to 10 to 20dB in the results of previous studies, where the road and the tire are modeled with smooth surfaces. A first attempt at an analytical description of the horn effect was made by Ronneberger [START_REF] Ronneberger | Towards quantitative prediction of tyre/road noise[END_REF]. Kropp et al. [21] suggested a theoretical model based on multipole synthesis.

The model can provide a reasonable prediction of noise levels at mid and high frequencies for a tire placed on a hard surface. However, it overestimates the horn amplification effect at low frequencies. Graf et al. [START_REF] Graf | Horn amplification at a tyre/road interface-part i: experiment and computation[END_REF][START_REF] Graf | On the horn effect of a tyre/road interface, part i: Experiment and computation[END_REF] first investigated experimentally the horn amplification of sound generated by a simple acoustic source. The boundary element method is then shown to give predictions. The dependence of the horn-effect on different geometrical parameters is also investigated both through experiments and boundary element calculations. It shows that for the intermediate frequency range the BEM provides an excellent tool to calculate the horn effect for practical geometries. The aim of the work by Anfosso et al. [START_REF] Anfosso-Ledee | Tyre / road noise horn effect : 2d modelling by analytical and numerical models[END_REF][START_REF] Anfosso-Ledee | Tire/road noise: comparison of 2d and 3d models for horn effect[END_REF] is also to predict the amplification due to horn effect.

Sound pressure amplification of a 2D infinite rigid cylinder is obtained using the analytical approach based on modal decomposition of sound pressure. It gives quick and accurate results, but is limited to simple geometrical configurations and purely reflecting properties of boundaries. In [START_REF] Fadavi | Tire/road noise: 3d model for horn effect[END_REF] Fadavi et al deal with the horn effect using a 3D cylinder tire model. The sound pressure and sound amplification are calculated in the space around the 3D tire model using the Boundary Element Method. The influence of different parameters such as the position and size of the source are studied in terms of amplification and sound pressure spectrums. All these studies are made for smooth roads and tires and do not take into account the real geometry of the tire or the road.

In this work, we want to estimate the influence of non smooth geometries on the horn effet. For this, we focus on network resonators and use several assumptions for the networks. There are only right-angled junctions in the networks. The pipes in the networks have the same cross-section. The networks could have open or closed ends. For the open ends, end corrections depend on flange shapes. So, first, methods for the calculation of end corrections will be introduced in section 2. Next, in section 3, a numerical method for the calculation of resonant frequencies of network resonators will be developed. Then, in section 4 an optimization method will be proposed to get the targeted resonant frequencies. Some examples of the application of the optimization method are shown in section 5 while comparisons with experimental measurements are given in section 6. Last some conclusions will be given.

Determination of end corrections

The length is an important parameter for calculating the resonant frequencies of a network with open ends. A short distance should be added to each end of the network to get precise results. This short distance is called the end correction, which makes each straight part of the network a little longer than its physical length.

From the perspective of waves, standing waves occur during the network resonances. The sound waves are reflecting at open ends, which are not perfectly at the end sections of the network, but at small distances (end corrections) outside the network.

The end corrections of the network open ends can be obtained from the radiation impedances which have small but finite values by (1) from [START_REF] Dalmont | Radiation impedance of tubes with different flanges: numerical and experimental investigations[END_REF].

δ = Re[k -1 arctan( -Z r iρc )] (1)
The upper script ∼ means that it is a frequency-dependent quantity. Here only the real part of the end correction is considered, which is the most useful in the present study. To estimate the end corrections of the network, the radiation impedances of the open ends should be calculated first by the impedance transfer equation of an acoustic transmission line (2) from [START_REF] Dalmont | Radiation impedance of tubes with different flanges: numerical and experimental investigations[END_REF], because Z r cannot be calculated or measured directly at the pipe end.

Z r = -iρc tan[arctan( -Z l iρc ) -kl] (2)
Z l is the impedance at an abscissa x = -l, i.e., at a distance l from the open end. It can be calculated as Dalmont did using a BEM numerical method [START_REF] Dalmont | Radiation impedance of tubes with different flanges: numerical and experimental investigations[END_REF].

Equation [START_REF] Zwikker | Sound Absorbing Materials[END_REF] means that the radiation impedance can be obtained from the case where Z l is an input impedance of a pipe of length l. Then the end Only the end corrections of longitudinal pipes will be discussed. For transverse pipes they can be calculated approximately by Dalmont's fit formula [START_REF] Tijdeman | On the propagation of sound waves in cylindrical tubes[END_REF] for rectangular flanges because the flange of transverse ends is flat.

δ sq = δ sq∞ + a sq b sq (δ sq0 -δ sq∞ ) + 0.057 a sq b sq [1 -( a sq b sq ) 5 ]a ef f (3)
with δ sq∞ = 0.811a ef f and δ sq0 = 0.597a ef f , in which a ef f = 2a sq / √ π. Here, 2b sq is the flange width, respectively. b sq is the shorter one of the two distances between the transverse end and the sides AD or BC in Fig. 2 for which the value of b sq for pipe number 2 is shown. 2a sq = 0.009m is the pipe width which is small and not shown in the figure. In order to calculate the end corrections of longitudinal pipes, half a cylinder is meshed for BEM, which is shown in Fig. 3a and3b. This is a longitudinal pipe, like pipe 1 in Fig. 2, but located at the center of the contact zone. Since the plane surface is rigid, it can be considered as a symmetric plane. A symmetric plane of the cylinder exists, so only half of the cylinder is meshed. The radius of the cylinder is 0.27m. The half pipe has rectangular cross-section with area of 0.0045m × 0.009m. The length is 0. Other parts of the model are rigid.

The acoustic pressure at the central node of the closed end is calculated by a BEM software. This software was developped by the authors and some details on the formulation which has been used can be found in [START_REF] Duhamel | L'acoustique des problèmes couplés fluide-structure -application au contrôle actif du son[END_REF]. For the computations in this article, first order elements of triangular or quadrangular shapes were used. The number of nodes was approximatly 1600 and the number of elements 2900. This was found sufficient for the frequency band which is studied in the following.

The acoustic velocity at the closed end of the pipe is unity, so the impedance of the piston is obtained. Then the radiation impedance is calculated from this impedance by equation ( 2). The end corrections of the longitudinal pipe for cylinders of different widths are shown in Fig. 4 for ka < 0.23, and the frequency interval is 200Hz. They are obtained by BEM as no analytical formula can be used in this case. For each width of the cylinder, the end corrections are frequency-dependent, but their standard deviations are very small (see Fig. 5), which indicates that they tend to be very close to the mean values. The standard deviation is calculated by equation ( 4). So the mean values of end corrections for each width in Fig. 5 are used to get a fit formula of end corrections [START_REF] Field | Theory and applications of quarter-wave resonators: A prelude to their use for attenuating noise entering buildings through ventilation openings[END_REF], in which w is half of the width.

σ = 1 N N i=1 (x i -µ) 2 (4)
with µ = 1 N N i=1
x i , where x i is the end correction at each frequency and N is the number of frequencies calculated.

δ = 0.00808 + 0.22128w -3.72112w 2 + 19.80897w 3 (5)
This fit formula will be used in section 4. The same procedure can be used to get fit formulas for other pipes and flanges of different shapes and dimensions.

Calculation of resonant frequencies 160

In the network, there are columns of air. Waves traveling in air will reflect back when they reach the end. A standing wave is created at the resonant frequency of the network. An open network will resonate if there is an antinode at each open end. These anti-nodes are places where there are maximum velocities and minimum pressures (p = 0). However, these zero pressures are 165 not at the physical ends of the network as they are altered by their contacts with air. In fact they are at the end correction positions of the network.

Knowing the resonant frequencies of the network is essential. The network has a great influence on the exterior acoustic field around the resonant frequencies, and at other frequencies there is no change of acoustic pressure. In order to calculate this influence the resonant frequencies should be estimated first, otherwise all the frequencies should be calculated and it leads to large computations.

There are analytical solutions for simple pipes such as a straight pipe, a T-shaped pipe and so on. However, numerical methods should be adopted in order to get the resonant frequencies of complex networks. It is assumed that there is a plane wave in the straight parts of the network for the cross-sections are quite small compared to the wavelengths.

Merkli [START_REF] Merkli | Acoustic resonance frequencies for a t-tube[END_REF] Theoretically, Merkli's model can be applied to other cases such as a Lshaped junction pipe, a cross junction pipe or a network. However before estimating the resonant frequencies, the end corrections of branches at the junction positions should be calculated precisely. Existing models can only give approximate estimations of these interior end corrections. If we use Merkli's model to calculate the resonant frequencies of a network, there will be large errors due to the approximate interior end corrections. In order to avoid using these interior corrections, numerical methods should be adopted for the calculation of the resonant frequencies.

The resonant frequencies can be obtained by solving an eigenvalue problem For a 2D network whose junctions and branches are in the same plane, an automatic calculation procedure can be implemented to get the resonant frequencies. Abaqus GUI will generate an input file '*.inp' which is sent to the processor while running a simulation. A simple case of a straight pipe is solved to get the '*.inp' file which can be modified for complex networks. In this file, the straight pipe mesh information is deleted, then mesh information of the network to be solved is added. New node and element sets are defined for the zero pressure boundary conditions. The other parts of this file keep the same data as before.

Since 2D meshes are quite easy to get, Matlab is used to create the mesh information for the network, and the node and element sets for the boundary conditions. The other information from the old file of straight pipe is written into the new '*.inp' file by Matlab as well.

The automatic procedure for calculating the resonant frequencies of 2D networks is: create the '*.inp' by Matlab, submit it to Abaqus by commands in Matlab, and then post-process the Abaqus output script in Matlab. This Mat-lab programme is named as '2DNRF' (for 2D Network Resonance Frequency), which will be used in section 4.

Optimization of network structures

The value and number of resonant frequencies vary according to the network structures. Because of this dependence, it should be possible to find the wanted resonant frequencies or a maximum number of resonant frequencies by optimizing the network structure.

The parameters that describe a network are the number and positions of Then the initial population can be generated by using a random number generator. There are two parts in a population, a binary part of network dimensions and an integer part of junction types. We can create a random binary matrix of size N ind × Lind for the parameters of network dimensions, where N ind specifies the number of individuals and Lind the length of the individuals.

For the parameters of junction types, we can give an integer (0, 1 and 2) matrix of size N ind×Lind jun where Lind jun is the number of junctions. By combining these two matrices, the initial population is obtained. The purpose of this work is to find the wanted resonant frequencies or as many resonant frequencies as possible by designing and optimizing the network.

The 2D FEM, implemented in the MATLAB code 2DNRF proposed before, has been used for estimating values of f r and the number of resonant frequencies of a network. If f w is the wanted resonant frequency and there are several resonant frequencies f r1 , f r2 , ... for the network i, the objective function for the first purpose is given by

ObjV 1 (x i ) = min(|f r1 -f w |, |f r2 -f w |, ...) (8)
where x i is the chromosome of network i.

If the purpose is to find as many resonant frequencies as possible, the objective function is the number of resonant frequencies. A minus sign is added to get a minimization problem. One has

ObjV 2 (x i ) = -count(f r1 , f r2 , ...) (9)
We can minimize the two objective functions, which only depends on the parameters of the network (dimensions and junction types). A population is first initialized and then improved through repetitive application of the mutation, crossover and selection operators. This process is repeated until a fixed number of generations has been reached. If we are not satisfied with the results, we can adjust the specified parameters of GA or networks and then run the optimization program again until we get targeted resonant frequencies.

Design examples

In order to illustrate that GA works for the optimization of 2D networks and that the resonant frequencies can be obtained by the GA process, some examples are given.

All the dimension parameters of the network can be optimized within given ranges during the GA process, but for the sake of simplicity some of them are specified. The network to be optimized in this section has 14 open ends and 12 junctions. The junction positions are arranged in four columns and three rows, and their coordinates depend on end coordinates. In Fig. 8 there is an example of networks generated randomly in the first generation of the GA procedure. In Three types of junctions introduced before can be seen in this example. They are T junction with left branch, T junction with right branch and cross junction.

The corrections of open ends can be obtained by the methods introduced before. If the ends are closed, there is no need to add end corrections to the original pipe lengths.

Unflanged networks

In this example there is no flange, so the end corrections, 0.001684m, can be calculated by equation [START_REF] Inácio | Design of duct cross sectional areas in bass-trapping resonators for control rooms[END_REF] which is from paper [START_REF] Dalmont | Radiation impedance of tubes with different flanges: numerical and experimental investigations[END_REF]. By giving the GA parameters, such as the number of individuals, the generation gap, the maximum number of generations and the wanted resonant frequencies, and running the GA program once, an optimal network can be found. This network has the closest resonant frequency to the targeted resonant frequency. The GA parameters should be adjusted for each case to obtain acceptable results. In Fig. 10 we can see the minimum difference between the targeted frequency 1400Hz and the resonant frequencies of individuals in each generation in GA procedure. In the first generation the difference is 259.52Hz. From the second generation it becomes 6.93Hz. In the 7th generation a very good result is found. The difference between its resonant frequency and the targeted frequency 1400Hz is 0.22Hz. The number of individuals in each generation used in the GA procedure is 1000. This leads to a computing time of about two hours to get the final result by the GA algorithm.

δ sq0 = 0.597a ef f (10)

Flanged networks

In this example the network is between the cylinder and the plane surface used in section 2. The calculations of open end corrections are presented before.

The end corrections of longitudinal open ends can be calculated by formula [START_REF] Field | Theory and applications of quarter-wave resonators: A prelude to their use for attenuating noise entering buildings through ventilation openings[END_REF].

For the transverse ends their corrections, 0.0054m, 0.0057m, and 0.0054m, are given by formula (3). Longitudinal and some transverse coordinates of the ends are given in table 3. The other transverse coordinates vary within the ranges which are shown in table 3. The pipe cross-sections are the same, 0.009m × 0.009m. Boundary conditions p = 0 should be applied to the open ends, where p is the acoustic pressure. In table 3, EC means the value of longitudinal end correction, which can be calculated by formula [START_REF] Field | Theory and applications of quarter-wave resonators: A prelude to their use for attenuating noise entering buildings through ventilation openings[END_REF].

In this section we try to get networks with the maximum number of resonant frequencies within the frequency range 0 -2000Hz. With the dimension In Fig. 12, the maximum number of resonant frequencies of a network in the first generation is 3. It changes to 4 in the 8th generation and then keeps the same value until the end of the GA procedure. Since we are interested in periodic networks, only networks with repeated junctions could be generated in each generation. So the number of individuals in each generation is just 30.

From the above examples one can conclude that the GA process developed before is suitable for the optimization and design of networks. Once the ranges of dimension parameters of networks are given, networks with targeted resonant frequencies can be found. The design examples will be validated by measurements in section 6.

Experimental validation

Wooden networks are built and measured in order to validate the optimization in section 5. First a network without flange is measured. This network is optimized and built to target the resonant frequency 1400Hz. Then a network between a cylinder and a plane surface is built and measured to search 4 resonant frequencies predicted in section 4.

Unflanged network

An unflanged network in Fig. 13a is measured in order to validate the optimization. The network in Fig. 13a is built with wood. A speaker and a microphone are put near the open ends in Fig. 13a. The optimized network is a 2D network, so the depth is not given in the optimization. In the experiments, the depth that we use is 0.01m.

The SPL obtained by the microphone is shown in Fig. 13b. We can see a deep valley at frequency 1370Hz which is close to the targeted resonant frequency 1400Hz. So the GA optimization procedure developed before can give the resonant frequencies that we want.

Flanged network

The network between the cylinder and the plane surface is optimized in section 5.2. The acoustic fields of network 1 in Fig. 11a are calculated and SPL. The lower dip in the experimental curve compared to the computation can be explained by the damping in the system coming for instance from the wood material. From the predicted and measured SPL we can see that the optimized wooden network has the resonant frequencies that we want.

Conclusions

A numerical method for the calculation of resonant frequencies of network resonators has been proposed. Based on this numerical method, an optimization method using genetic algorithm is developed in order to get the targeted resonant frequencies of the network resonators. The optimization method is validated by experiments of design examples of wooden network resonators. The measured resonant frequencies of the optimized network resonators agree well with the targeted resonant frequencies. The good agreements also prove that the end corrections are estimated correctly.

Tire treads and road textures in the contact zones between tires and roads can be considered as networks. The network resonance is an important mechanism of the tire/road noise. With the methods proposed in this work, it is possible to investigate the influence of these networks on the tire/road noise and to design tire treads and road textures.

For a real tire the method could be applied by first estimating the end corrections of the pipe. This will need a fine mesh of the tire surface and potentially large computations but efficient methods such as BEM based on Fast Multipole Methods could help to get results in a reasonable time. Computations of resonant frequencies of the network in the contact zone should be done without too much difficulties. The method can also be applied to estimate the influence of the road surface of the acoustic radiation. This needs to describe the road asperities and to mesh a part of the road in the boundary element model.

Figure 1 :

 1 Figure 1: Network resonators in the contact zone between a tire and a road

Figure 2 :

 2 Figure 2: A network (in red) between a round surface and a rigid plane surface

Figure 3 :

 3 Figure 3: (a) Half a mesh of the boundary element model of a rectangular tube with a cylindrical flange; (b) Details of the mesh of the tube.

  1m. It has an open end and a closed end which has a unit velocity as boundary condition. The base surface behind the piston is modelled as flat to reduce the elements because the flange shape behind the piston has no influence on the end correction of the open end of this pipe. It has a very small impedance which is used to minimize the reflections.

Figure 4 :

 4 Figure 4: End corrections of longitudinal pipes with cylindrical flanges of different widths within 2000Hz (ka < 0.23).

Figure 5 :

 5 Figure 5: Standard deviations and mean values of end corrections of longitudinal pipes with cylindrical flanges of different widths.

  proposed a simple model to calculate the resonant frequencies of a T-shaped resonator by using the wave propagation theory. In this model, end corrections for open ends should be considered. Besides, the end correction of each branch at the junction position should also be included in the model. So for each open branch, the effective length includes the physical length of the branch, the end correction at the junction position and the end correction of the open end. Dalmont's [27] methods and results can be used for the calculations of the open end corrections. With his methods, the open end flanges could have any shape and dimension. The end corrections at the junction position can be calculated with the model of Li [12].

( 6 )

 6 of an undamped finite element model. (K -ω 2 M )φ = 0 (6) K is the stiffness matrix, M is the mass matrix, ω = 2πf and φ is the eigenvector. Finite element software Abaqus is chosen to perform the resonant frequencies extraction procedure, which is a linear perturbation procedure. The networks have open ends. The impedance boundary conditions cannot be applied to these ends in Abaqus. So their end corrections should be taken into account in the models. The branches with open ends in finite element models are created longer than their physical lengths. Since at the resonant frequencies the pressures are zero at the end correction positions, zero pressure boundary conditions are applied. The other boundary conditions are rigid. The values of these end corrections for open ends are computed by relation (5). Then the network with corrected lengths for the open ends is meshed.

  ends, junction types, junction positions and pipe cross-sections. In this work there are only longitudinal and transverse pipes in a network, so the junction positions depend on the end positions. If the end positions are known, the junction positions are known. The 2D network considered in this work consists of the three types of junctions shown in Fig.6a-6c.

Figure 6 :

 6 Figure 6: (a) T junction with left branch; (b) T junction with right branch; (c) Cross junction

Figure 7 :

 7 Figure 7: An example of network for the chromosome representation

For

  the minimization problem, the most fit individuals have the lowest numerical values of the associated objective function. The raw objective values in equation (8) or (9) are usually only used as an intermediate stage in determining the relative performance of individuals. The fitness function is normally used to transform the objective function value into a measure of relative fitness. Here, individuals are assigned a fitness according to the rank of their raw objective values in the population rather than the raw performance.

Fig. 8

 8 Fig.8 we can see 14 positions for the open ends, but the network has 12 open ends due to the junction types. The circles represent the junction positions.

Figure 8 :

 8 Figure 8: An example of networks generated randomly in the first generation of the GA procedure

Figure 9 :

 9 Figure 9: (a) Network with the resonant frequency 1254Hz; (b) Network with the resonant frequency 1400Hz; (c) Network with the resonant frequency 1590Hz.

Figure 10 :

 10 Figure 10: The minimum difference between the targeted frequency 1400Hz and the resonant frequencies of individuals in each generation in the GA procedure

Figure 11 :

 11 Figure 11: (a) Network 1; (b) Network 2.

Figure 12 :

 12 Figure 12: The maximum number of resonant frequencies for each generation in the GA procedure

  355

Table 1 :

 1 Coordinates of central points of open ends of a unflanged network

	End	x(m)	y(m)	End	x(m)	y(m)
	1	0.0475	-0.051684	8	-0.0475	0.051684
	2	0.0325	-0.051684	9	-0.0325	0.051684
	3	-0.0325	-0.051684	10	0.0325	0.051684
	4	-0.0475	-0.051684	11	0.0475	0.051684
	5	-0.076684 [-0.0475, -0.015]	12	0.076684	[0.015, 0.0475]
	6	-0.076684	[-0.01, 0.01]	13	0.076684	[-0.01, 0.01]
	7	-0.076684	[0.015, 0.0475]	14	0.076684 [-0.0475, -0.015]

Table 2 :

 2 Results for the targeted resonant frequencies

	Case Targeted(Hz) Obtained(Hz) Error(%)
	1	1250	1254	0.32
	2	1400	1400	0
	3	1600	1590	0.625
	In table 2, the wanted resonant frequencies are obtained by optimizing the
	network structure and the maximum error is less than 1%. The network struc-
	tures can be seen in Fig.9a-9c. Besides the resonant frequencies shown in table
	2, these three networks have other resonant frequencies within 2000Hz. They
	are 1926Hz in case 1, 1976Hz in case 2 and 1947Hz in case 3.

Table 3 :

 3 Coordinates of central points of open ends of the network between a cylinder and a

	plane surface
	End	x(m)	y(m)	End	x(m)	y(m)
	1	[0.042, 0.0705]	-0.05 -EC	8	[-0.0705, -0.042] 0.05 + EC
	2	[0.0045, 0.033]	-0.05 -EC	9	[-0.033, -0.0045] 0.05 + EC
	3	[-0.033, -0.0045] -0.05 -EC	10	[0.0045, 0.033]	0.05 + EC
	4	[-0.0705, -0.042] -0.05 -EC	11	[0.042, 0.0705]	0.05 + EC
	5	-0.0804	-0.03333	12	0.0804	0.03333
	6	-0.0807	0	13	0.0807	0
	7	-0.0804	0.03333	14	0.0804	-0.03333

Table 4 :

 4 Networks with four resonant frequencies

	Resonant frequency	1st	2nd	3rd	4th
	N etwork1			1055Hz 1797Hz 1799Hz 1929Hz
	N etwork2			1201Hz 1799Hz 1890Hz 1989Hz
		5
	maximum number of resonant frequencies	3 4
		2
		2	4	6	8 10 12 14 16 18 20 22 24 26 28 30
					generations

Acknowledgment

This work was funded by the China Scholarship Council (CSC) and by the French Environment and Energy Management Agency (ADEME).

measured in order to validate the GA optimization methods. When we measure the case without network, we close the pipe ends in Fig. 14b with woods.

In our calculations, a dimensionless point source is used, and it has been assumed omni-directional. The general tendencies and frequency-dependant variations of the sound pressure will be compared between the predicted and measured results. Such comparisons are very common and widely used in previous studies such as in [START_REF] Cummings | The effects of a resonator array on the sound field in a cavity[END_REF] and [START_REF] Yu | Acoustic resonators for noise control in enclosures: modelling, design and optimization[END_REF]. So it is not necessary to use a omnidirectional source in our experiments. A numerical signal is generated and then sent to a real loudspeaker. This is the source used in these experiments. Its dimensions are 0.12m × 0.12m × 0.12m.

The radius and width of the cylinder are 0.27m and 0.15m. Its location can be seen in the sketch of the experimental setup Fig. 14a. Sweep signals within 2000Hz are generated by a generator. The center of the speaker is at (1m, 0m, 0.06m). The microphone is at (0.1m, 0m, 0.005m).

The predicted results are shown in Fig. 15a. The resonant frequencies of this optimized network are given in section 5.2, which are 1055Hz, 1797Hz, 1799Hz and 1929Hz. The second and the third resonant frequencies are very close, so just one extremum can be seen around 1800Hz in Fig. 15a, where we can see two other extrema around 1055Hz and 1929Hz. The measured results are given in Fig. 15b, where the variations of SPL are similar to the predicted results in Fig. 15a. Around the wanted resonant frequen-


DESIR (DARIAH ERIC Sustainability

Refined) work package 4 Technology contributes to DARIAH's long-term sustainability by technologically enhancing DARIAH's research infrastructure and services. To this end four new and innovative technology areasentity-based search, scholarly content management, text analytic services and visualisationshall shape DARIAH's profile. The present document forms a prerequisite for the aforementioned objective and conducts for that reason a gap analysis of the current DARIAH infrastructure, concentrating on four areas: text analytic services, scholarly content management, entity-based search and visualisation. The competencies and resources of the three technology partners in this work package correspond to these four areas. The conceptual models -as proposal for the identified gaps -are subject to later deliverables in the project, but in the course of undertaking the gap analysis already first impressions of possible conceptual models are apparent and will be presented here. The concept of the gap analysis in this context means not only to identify missing tools or services in the DARIAH infrastructure landscape but also to recognize potential for enhancement with already existing tools and services. 1 Baillot, Mertens, Romary (2016), p. 153 2 http://www.

1

Introduction and scope of the report "Presently, there exists a vast library of tools, services, software [...]. One of the principal aims of DARIAH is to promote and facilitate the re-use of such materials, in order to accelerate new research, enable a more responsive and open publishing environment for humanities data, allow collaborations to be concluded more efficiently, with the overall goal of supporting not just digital services and complex digital objects in arts and humanities research but to broaden and deepen the adoption of digital methods and digital workflows amongst humanities scholars." 1 This overall mission statement of DARIAH -the Digital Research Infrastructure for the Arts and Humanities -is also guiding the DESIR project.

2 Against this background the aim of work package 4 and the document at hand is twofold: first and foremost an inventory of the current DARIAH infrastructure according to four specific areas will be compiled. These areas include entity-based search, scholarly content management, text-analytic services and visualisation. This structured overview represents the current status quo not only in terms of general infrastructure but also in terms of individual tools, services or software, being provided or maintained by DARIAH. The inventory should ideally cover in this context all national branch activities -e.g. DARIAH-DE or DARIAH-FR -and includes also DARIAH-EU resp. the DARIAH ERIC as 3 supranational administration umbrella for all DARIAH activities. Nevertheless our gap analysis will only result in a fragmentary picture of all existing activities, also because it is 4 not necessary in this respective context. On the one hand this is connected to the by now huge bandwidth of European DARIAH activities and the steady expansion in terms of participating countries, community growth or differentiating services and resources. On the other hand there is currently no overarching inventory or registry, although there are several inventories on a national level. The upcoming DARIAH market place could possibly be some kind of central information hub for services, tools and resources -at least for the in-kind contributions of the partner countries and will be marked in the subsequent chapter. With regard to the description of work this fragmentary picture shouldn't be a problem as the main outcome of this work package shall be conceptual models with potential of contributing to the DARIAH landscape. Secondly the resulting DARIAH inventory will undergo a gap analysis with respect to technology specialisations on side of the DESIR technology partners. The gap analysis will focus on four main areas which have been predetermined by the description of work for the DESIR project:

• entity-based search,

• scholarly content management,

• text-analytic services and • visualisation. The document at hand should not only identify gaps in the DARIAH inventory but rather explore possibilities to close the gaps. This step will be detailed subject of the subsequent deliverable D4.2 Conceptual Models. D4.2 has to present conceptual modules for the identified gaps with respect to the aforementioned four areas. The further process of work package 4 will subject the conceptual models to a code-sprint, validate them, and prepare a proof-of-concept.

2

Technology partners in WP4 As extension of the preceding information compilation we prepared an overview on the partners' applied workflows and technologies in order to better understand the course of the work in work package 4. By this we are able to evaluate the DARIAH inventory right from the start with the available resources and competencies in mind as preparatory work for the collection of ideas for conceptual models or demonstrators.

Applied technologies among the technology partners

The following table lists the applied development, maintenance and provisioning technologies amongst the partners in WP4. This information can be useful to assess compatibilities or synergies in the development of the conceptual models.

Service roles among the technology partners

The table below collects some meta-information on the roles of the technology partners. Aim of this paragraph is to be able to evaluate the yet to come conceptual models in a strategic perspective. Context: it is not uncommon that service are being developed by an institution and that the same institution subsequently takes further care of the service, be it as service provider, maintainer or in a developer role. As long as the institution already fulfils all of these roles, this may be unproblematic. In practice many institutions are unhappy with the maintainer and provider role but fulfil them given that there is no regulating policy available for this issue. The abovementioned diagram has to be read with some scepticism as with one exception -ICM -all partners envisage themselves not in the service provider role. Partly and motivated by the development and further support for certain services a partner might be sliding into a maintainer and/or provider role but usually don't take this role. Read with a certain degree of sincerity one can assume that all partner institutions see their focus on research and research-related development activities. Maintenance and provision comes inevitably here and there into effect but is clearly not seen as work focus and is always dependent on the available funding resources. This leads to certain consequences for the development of digital services and resources, mainly in terms of standardisation and documentation.

Current services or software among the technology partners

Inventory of DARIAH activities in four areas

The following section provides an overview of the current infrastructure and service offerings of DARIAH according to the four areas: entity-based search, scholarly content management, text-analytic services and visualisation. As mentioned before, this deliverable is not tasked with the preparation of a comprehensive inventory but is said to focus on certain areas.

In the following step this inventory will be screened for gaps -or rather potentials -for contributions by the technological partners in DESIR. The table presents publicly offered services such as desktop applications, web applications, mobile applications and APIs, basically in the sense of service as the DARIAH (in kind) contribution tool understands them: (data) hosting service, (processing) service, support service and access to resources. The services may be aimed at basic infrastructure requirements, scholarly collaboration, conducting of research and user services. Where possible, the services are linked with a URL. The listed resources focus on services, tools and software instead of content. Therefore publication and research data repositories or digital editions are intentionally left out. This selection is not always possible, this is why to some degree databases have been incorporated in the inventory. Again: an exhaustive inventory of all available DH resources within DARIAH will be only within reach with the upcoming marketplace. Also the reliability of the collected information has to be considered. Information on websites regarding the status of a service are often unclear. Is it still being developed, is it a productive service being used, is the service discontinued and just present for documentation purpose? To address this issue a column has been added in the table, displaying the maintenance status of the services. An x in this column indicates that from the information on the website we assume that the service is still active to some degree. So far the following sources have been investigated for services : Table 1: Technology partners in DESIR WP4

Figure

  Figure 1: Service roles of technology partners in DESIR

Figure 2 :•

 2 Figure 2: Services and software among the technology partners in DESIR WP4

Figure 3 :

 3 Figure 3: The DARIAH In-Kind Contribution tool (as of November 2017)

  12 http://it.dariah.eu/registro/en/ 13 http://www.parthenos-project.eu/Download/Deliverables/D5.2_Report_on_design_Joint_Resource_Registry.pdf 14 https://www-dev.dariah.eu/what-we-provide/tools-list/ 15 https://de.dariah.eu/list-services which will perspectively be included in the DARIAH-EU Marketplace 16 http://dasish.eu/ 17 http://teresah.dariah.eu/ 18 See here http://teresah.dariah.eu/about/rdf DESIR INFRADEV-03-2016-2017 -Individual support to ESFRI and other world-class research infrastructures, Grant Agreement no. 731081.

19•

  DARIAH-DE: https://de.dariah.eu/list-services contains a comprehensive list of available services and tools that qualify for production use. As DARIAH-DE passed through two funding phases and is now in the midst of the third funding phase and paid considerable effort to the sustainability of the created infrastructure, the overview -nearly a service catalogue -on the DARIAH-DE website is a reliable portfolio of available and functional services. A comprehensive -although in German language -overview of the service portfolio can be found in Kálmán, Kong, Schwardmann (2016). 20 • DARIAH-EU: the website http://dariah.eu/ gives currently only a glimpse overview of the resources that have been developed within the national branches of DARIAH. Even the relaunched website of DARIAH-EU will only be able to offer a complete 21 overview once the DARIAH Marketplace will be launched. The reasoning behind the DARIAH Marketplace and the according In-Kind-Contribution Tool is described a bit more in the previous chapter. • DARIAH-IT: http://it.dariah.eu/sito/strumenti/ showcases a broad collection resources being developed in humanities-related research contexts in Italy. The relation to DARIAH is more or less loose which makes it difficult to identify services that are functional and accessible beyond a funded project period. Beyond this, it remains unclear along which criteria the resources have been selected or whether they are up to date. Therefore only a small assortment has been selected for the inventory below and still the listed resources have to be considered with caution. 19 As of September 2017. 20 Kálmán, Kong, Schwardmann (2016), p. 234ff. 21 https://www-dev.dariah.eu/what-we-provide/tools-list/ as preliminary development instance. DESIR INFRADEV-03-2016-2017 -Individual support to ESFRI and other world-class research infrastructures, Grant Agreement no. 731081. • DARIAH-GR: the website of Greek DARIAH branch http://www.dyas-net.gr/ contains a list of Greek humanities-related tools and services. As long as the resources seem to be available in English they have been considered for our inventory. • DARIAH-BE: the website of DARIAH-BE http://be.dariah.eu/services-overview offers a comprehensive list of tools and services for digital scholarship in the arts and humanities in Belgium. Although it is not clear along which criteria the resources have been selected, the listed resources give the impression to be more or less functional and available. • DARIAH-AT: http://www.digital-humanities.at/de/dha/projects the Austrian DH resources reveal a strong emphasis on digital editions or other content-focussed resources. Only a few of them are considered in the inventory below although they make the impression of being functional and accessible on a beyond-project base. Another feature of the Austrian resources is the CLARIN provenance. Services with a clear CLARIN provenance haven't been considered in the inventory. • DARIAH-FR & Huma-Num: http://www.huma-num.fr/services-et-outils Huma-Num serves as gathering point for humanities-related French research services. Huma-num mission is to ensure the preservation of the scientific heritage of the laboratories and to reduce recurrent costs by pooling an infrastructure by co-managing and sharing tools, instruments and data management systems. Huma-num is also part of the DARIAH organisation providing their infrastructure for european projects. • CLARIAH-NL: https://www.clariah.nl/en/ The Common Lab Research Infrastructure for the Arts and Humanities is not a national DARIAH branch as DARIAH-DE or DARIAH-BE but can be explained with the strong CLARIN uptake in the Netherlands. CLARIAH-NL offers a distributed infrastructure for the humanities and social sciences. Different from the national DARIAH websites above, CLARIAH doesn't offer list or registry of tools and services on its website. • For Switzerland, the ASSH has open a German webpage for DARIAH announcements: http://www.sagw.ch/sagw/laufende-projekte/dariah.html The aforementioned list of resources is by no means complete but may be sufficient for an overview of the available services to deduct focal points or gaps. to keep in mind, that the inventory is fragmentary. The reasons for have been explained above and are related to the situation in DARIAH that in 2017 -the time of writingthe marketplace is not yet available. There is no comprehensive overview on the DARIAH landscape. For this reason, the fragmentary inventory may be better understood as indication for specific competencies or centers of gravity. The large presence of scholarly content-related services may indicate such a center of gravity. The analysis of the figures follows below. The table below is an aggregated facet of the inventory above. It groups all 110 services into three categories: infrastructure, research, and communication. The finding is -not surprisingly -that most DARIAH activities can be related more or less directly to this hasn't been done in this document. It would have been impossible to gather the user requirements of the current DARIAH user base. This could be subject to a larger undertaking, which is not possible and not within the scope of this work package. So one has to consider, that the aforementioned inventory of DARIAH's services and resources is fragmentary and represents a snapshot of the situation in autumn 2017. It has been compiled with regard to the requirements of the DESIR project, therefore focussing on four categories -entity-based search, text-analytic services, scholarly content management and visualisation. The inventory indicates centres of gravity of DARIAH in terms of services and resources. Areas with a lesser accumulation of services -for instance entity-based search -can be identified but one cannot inevitably deduct a gap from this. The gaps will be later defined in another, more indirect manner: with look at the DARIAH inventory the technology partners in WP4 draft ideas for possible innovative services and resources. As long as the idea for a service meets a potential demand in the DARIAH community and is coincidentally innovative and functional it addresses a gap in the sense of this work package. The analysis of the current DARIAH service portfolio leads to the following conclusions, which may be later used as basis for discussion of the conceptual models. 4.2 Interpretation of findings DARIAH's services and resources concentrate on research related services. To a lesser degree services may be associated to infrastructure and communication (compare figure 4 below). These three categories come as an alternative facet to the four categories from DESIR's description of work. Although the gain of knowledge may be minor the result underpins the orientation of DARIAH as research infrastructure. Interestingly the communication related share of services is the smallest one, which may be based on the already sufficient availability of (free or commercial) communication tools. It is clear that research infrastructure initiatives can't compete with the established and widely-used tools as Skype, forums, messengers, e-mail. A different facet becomes possible when arranging the services along the DARIAH VCCs. The DARIAH Virtual Competency Centers function as an umbrella structure to coordinate and 40 promote DARIAH activities along four headlines: VCC1 -e-Infrastructure; VCC2-Research and Education Liaison; VCC3 -Scholarly Content Management Advocacy and VCC4 -Impact and Outreach. These categories differ a little bit from the infrastructural or technological view of the DESIR DoW but nevertheless the focus of DARIAH as research infrastructure becomes clear with 43 services relevant for scholarly content management (VCC3) and 66 services relevant for e-Infrastructure (VCC1). 40 https://www.dariah.eu/activities/competence-centers-list/ DESIR INFRADEV-03-2016-2017 -Individual support to ESFRI and other world-class research infrastructures, Grant Agreement no. 731081.

Figure 4 :Figure

 4 Figure 4: Services according to the categories research, infrastructure and communication

Figure 6 :

 6 Figure 6: Service categories according to Description of Work 41

Figure

  Figure 7: Frequency of services in DARIAH

Figures

  FiguresFigure 1: Service roles of technology partners in DESIR 1 Figure 2: Services and software among the technology partners in DESIR WP4 1 Figure 3: The DARIAH In-Kind Contribution tool (as of November 2017) 1 Figure 4: Services according to the categories research, infrastructure and communication Figure 5: DARIAH inventory according to four DARIAH Virtual Competence Centers Figure 6: Service categories according to Description of Work Figure 7: Frequency of services in DARIAH

for Mathematical and Computational Modelling, University of Warsaw Basic unit of the university; leading HPC and R&D centre in Poland; provides research infrastructure within ICT and HPC; interdisciplinary research; applied C/C++; Fortran; Java(Web, Desktop); Scala; Python; JavaScript; R; GitHub; GitLab; SVN; Redmine; Jenkins; Maven; Apache/Tomcat; Hadoop ecosystem; developer maintainer provider VisNow -a generic visualization framework http://visnow.icm.edu.pl DESIR INFRADEV-03-2016-2017 -Individual support to ESFRI and other world-class research infrastructures, Grant Agreement no. 731081. D4.1 Gap Analysis of DARIAH Research Infrastructure v1.0 | page 9 mathematics; computational sciences and data science multiple DB engines INRIA Institut national de recherche en informatique et en automatique represented by the ALMAnaCH team (Automatic Language Modelling and Analysis & Computational Humanities) INRIA is the French institute for computer science and applied mathematics; it promotes "scientific excellence for technology transfer and society"; divided in various research centres; no major policies in terms of software sustainability or applied technologies; only a centralised repository on GitLab is provided; development approach depends on specific team; open software; hosted externally Java; Python; Javascript (jquery, angularjs); Elasticsearch; lucene; mysql; Machine learning toolkits; NLP libraries; Maven; travis/jenkins; git; Json; XML (mostly TEI); XSLT developer maintainer (N)ERD -a (Named) entity recognition and disambiguation service: http://nerd.huma-num.fr http://github.com/kermitt2/nerd GROBID -Generation Of BIbliographic Data http://github.com/kermitt2/grobid http://github.com/kermitt2/grobid- ner http://github.com/kermitt2/grobid- quantities L3S at the University of Hanover Research interests of L3S: web science (Twitter, Wikipedia, etc.); Big Data (Hadoop, Spark, etc.); Text Mining; NLP; Data Mining; Machine Learning; Crowdsourcing; applied technologies and methods depend on the respective project, there is no mandatory standard procedure Java, Maven, Hadoop, Spark, (Scala), Python, Tomcat, MySQL, git, SVN, Jenkins, Weka, RapidMiner, Eclipse, IntelliJ, NLP libraries developer maintainer provider BibSonomy -a social bookmarking system for web links and literature references http://www.bibsonomy.org/

Table 2 : Applied technologies among the DESIR technology partners in WP4 Question ICM INRIA L3S UGOE-SUB (RDD) What workflows or methods do you employ? (Agile/Scrum vs. Waterfall, DevOps vs. HandOff, Git-Flow, etc.) No No (Yes for BibSonomy) No In which way do you document your code? Javadoc formalised in code review (VisNow). Comments (however not always a shared approach) Eclipse settings enforcing comments Javadoc, sometimes just comments, in part with Sphinx Where do you operate the systems? Own HPC Centre Inria research center server Dedicated/computing centre server rooms in Hannover, Kassel and Würzburg GWDG (local computing center) How do you provide systems? Openstack/ VMWare/ Bare Metal Bare Metal/ VMWare/KVM Our team has some dedicated Bare Metal servers. Bare Metal VMWare for important Services, Openstack, Some test systems on KVM on Bare Metal Do you use configuration management? (in ITIL sense or tools like puppet/ chef/ ansible) Yes: SVN, Salt, Ansible, Puppet The ALMAnaCH team has 5 servers. There are dedicated teams doing some basic maintenance. The rest is manual work. The servers are usually allocated for demos and heavy processing. No (config in RCS) Yes: Puppet, No ITIL How do you document systems and their state? Wiki, Nagios, Icing2 In a PAD, servers are usually not shared among many people. Wiki, Nagios Wiki, Nagios Do you use tools for time series analytics / metrics? Yes: MRTG, Munin, Zabbix No No Yes: Grafana for Telegraf Data Web/Usage Analytics Yes: Piwik, Other No Awstats, Piwik Piwik DESIR INFRADEV-03-2016-2017 -Individual support to ESFRI and other world-class research infrastructures, Grant Agreement no. 731081. D4.1 Gap Analysis of DARIAH Research Infrastructure v1.0 | page 11

 2

Table 3 : Service roles among technology partners in DESIR WP4 (self assessment) In which service roles do you see your institution? ICM INRIA L3S UGOE-SUB Researcher X 5 X X X Developer X X X X Maintainer X Provider X

 3

Table 4 : Development and service competencies among the technology partners in DESIR WP4

 4

	Service	Partner Tags	Entity-based	Scholarly	Text-analytic	Visualisation	Other
				search	content	services
					management
	https://www.bibsonomy.org/	L3S	Social	X 6	X
			Bookmarking

http://git.l3s.uni-hannover.de/ L3S Code hosting/ issue tracking X http://nerd.huma-num.fr INRIA Data extraction X https://github.com/helgeho/

Ar chiveSpark L3S Data extraction X X http://scraper.bibsonomy.org/ L3S Data extraction X http://traces1.saclay.inria.fr/gr obid INRIA Metadata conversion X X X https://hal.archives-ouvertes.fr /DARIAH INRIA Publication repository X X https://visnow.icm.edu.pl/ ICM Data visualisation X http://remotevis.icm.edu.pl/ (non-public)

		ICM	Desktop cloud				X
			visualization
	http://cermine.ceon.pl/	ICM	Data extraction	X	X	X
	http://comac.ceon.pl	ICM	Bibliography		X		X
			analytics
	https://repod.pon.edu.pl	ICM	Research data		X		X
			repository
	http://repozytorium.ceon.pl	ICM	Publication
			repository
	= 19 services			4	14	4	9	5

X http://bibliotekanauki.ceon.pl ICM Journal platform X http://otworzksiazke.pl ICM Book platform X

Table 2 : Applied technologies among the DESIR technology partners in WP4

 2

Table 3 : Service roles among technology partners in DESIR WP4 (self assessment) Table 4: Development and service competencies among the technology partners in DESIR WP4Table 5 : DARIAH inventory according to the four DESIR DoW categories Table 6: DARIAH inventory according to three aggregated categories Table 7: DARIAH inventory according to four DARIAH Virtual Competence Centers

 35

http://traces1.saclay.inria.fr/inri a/ INRIA Repository analytics X X X X https://textgridrep.org/en/ UGOE-S UB Research data repository X X X https://de.dariah.eu/repository UGOE-S UB Research data repository X X X https://textgrid.de/ UGOE-S UB Virtual research environment X X 6 X = applies DESIR INFRADEV-03-2016-2017 -Individual support to ESFRI and other world-class research infrastructures, Grant Agreement no. 731081.

Project website for Humanities at Scale: http://has.dariah.eu/

Baillot, Mertens, Romary (2016), p. 152

A provisional development instance of the In-kind contribution tool is available here: https://dariah-beta.dans.knaw.nl/data/contrib/filter , the technical documentation may be found here: https://dans-labs.github.io/dariah/ and the user manuals on Github here: https://github.com/Dans-labs/dariah/wiki

http://be.dariah.eu/project/ramses-online Content, database, corpus X X http://www.tic.ugent.be/ VRE X X X http://be.dariah.eu/project/dariah-vl-virtual-re search-environment-service-infrastructure-vr e-si VRE X https://transkribus.eu/Transkribus/ Data analysis X X X http://www.digital-humanities.at/de/dha/s-pr oject/read-recognition-and-enrichment-archiv al-documents VRE X http://www.digital-humanities.at/de/dha/s-pr oject/medcon VRE, network analysis X http://www.digital-humanities.at/de/dha/s-pr oject/mapping-historical-networks-apis VRE, content X X http://www.digital-humanities.at/de/dha/s-pr oject/gams Content, VRE X 34 Service is defined according to D5.2 DARIAH (in kind) contribution tool as (Data) hosting service, (processing) service, support service and access to resources. 35 Maintained or applicable is to understood as qualitative criteria in this regard. A service was recognized as maintained or applicable only if the hosting website appeared to be up to date.

Service is defined according to D5.2 DARIAH (in kind) contribution tool as (Data) hosting service, (processing) service, support service and access to resources.

Maintained or applicable is to understood as qualitative criteria in this regard. A service was recognized as maintained or applicable only if the hosting website appeared to be up to date.


archive ouverte pluridisciplinaire HAL, est destinée au dépôt

Objective & Background

Rooftop PV systems in urban areas are very interesting because (1) they do not emit pollutants nor GHGs during their exploitation, (2) they produce electricity where this electricity is consumed and (3) they add value to unused urban roofs. Solar resource assessment and mapping at the urban scale will thus be crucial to develop solar cadasterswhich are meant to analyze the solar potential on roofs, help public or private decision-makers and investors, as well as promote the development of rooftop PV systems in these urban areas.

This communication presents the high-quality and innovative solar cadaster for Nantes Metropole, developed by the French startup In Sun We Trust. This solar cadaster provides a free, accurate and easyto-use tool for the general public to assess solar potential of rooftop PV systems in the 30 km x 30 km region of Nantes Metropole, in the North-West part of France.

Method

The development of this solar cadaster has required:  a high-quality long-term solar resource dataset. We chose the database Helioclim-3, which provides solar irradiation data from satellite observations (www.soda-is.com). To improve the accuracy of our cadaster, we calibrated this dataset with local in-situ pyranometric measurements from Météo France;  a decametric digital terrain model (DTM) to describe the orography (SRTM, srtm.csi.cgiar.org);  a high-accuracy 10 cm digital surface model (DSM) to provide 3D description of buildings, vegetation and superstructures. This DSM has been provided by the IGN French national mapping agency, using aerial images correlation;  a high-accuracy map of buildings to provide location and contours of corresponding roofs. We chose to use BDTOPO provided by IGN.

We developed a specific algorithm to detect on roofs 1 m 2 planar patches without local superstructures, from the DSM. This algorithm also estimates the angular orientations of each patch. Additionally, we created an optimized algorithm to compute the local shadow mask for each detected patch. This algorithm uses several levels of details from the DSM and the DTM. With the local shadow mask, the angular orientation and the calibrated Helioclim-3 datasets we computed the long-term average of monthly sums of solar global irradiation. Finally, from these solar irradiations we infer energy production, environmental metrics and finance metrics to assess the potential of rooftop PV systems using simulation models.

Conclusion

The solar cadaster developed by In Sun We Trust for Nantes Metropole with the support of TRANSVALOR, IGN and MINES ParisTech is now operational and is available at nantesmetropole.insunwetrust.solar for free. In addition to the innovative methodology used to produce this solar cadaster, the funding method is also innovative. It is not solely based on public funds, but also partly supported by a business model with local selected PV installers, who are connected with potential clients thanks to the solar cadaster. It is believed that this first innovative solar cadaster will be used as a basis for future solar cadasters, to help every citizen and to promote rooftop PV systems in urban areas.

  Solar cadaster of Nantes metropole based on high resolution solar mapping at urban scale from 10 cm digital surface model for rooftop PV development D Callegari, N. Bodereau, M Bourgeon, A. Ebel, E Dion, M Force, E Séguin, Etienne Wey, Laurent Saboret, Benoît Gschwind, et al. To cite this version: D Callegari, N. Bodereau, M Bourgeon, A. Ebel, E Dion, et al.. Solar cadaster of Nantes metropole based on high resolution solar mapping at urban scale from 10 cm digital surface model for rooftop PV development. ICEM 2017, Jun 2017, Bari, Italy. hal-01695387 Solar cadaster of Nantes Metropole based on high resolution solar mapping at urban scale from 10 cm Digital Surface Model for rooftop PV development Callegari D.

  1 , Bodereau N. 1 , Bourgeon M. 1 , Ebel A. 1 , Dion E 2 , Force M 2 , E. Séguin 3 , E. Wey 4 , L.

	Saboret 4 , B. Gschwind 5 , P. Blanc 5
	1 ISWT 2.0, 42 avenue Alexandre 92000 Nanterre
	2 Nantes Metropole, 2, Cours du champ de Mars 44923 Nantes Cedex 9
	3 Institut National de l'Information Géographique et Forestière, 73 avenue de paris, 94165 Saint-
	Mande 4 TRANSVALOR, Parc de Haute Technologie, 694 Av. du Doc. Maurice Donat, 06255 Mougins
	5 MINES ParisTech, PSL Research University, Centre for Observation, Impacts, Energy, CS 10207 -
	06904 Sophia Antipolis, France

L'