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Tourism development has been a particularly intense area of negotiation in the Spanish countryside since the 1990s because of its major role in public policies for the economic restructuring, the regionalisation of policy instruments and its own intersectoral nature. This leads us to examine how the coordination takes place within the actors engaged in the tourist development of Sierra de Albarracín. This research adopts an inductive approach to the social relations that underlie the construction of a tourism project territory. From the meeting between the methodology of the social network analysis and the analytical framework of the School of Proximity, the procedure presented here helps to understand the logics of territorial construction. Cooperation appears more fictitious than the policy instruments of governance envisage. Questioning both cooperative and conflictive proximities offers new clues for the evaluation of public policy instruments.

Between 2007 and 2013, the European Rural Development Policy targets were supported by the LEADER policy, an instrument that can be interpreted differently according to each country. Based on the examples of France and Lithuania, we studied the way in which the institutional organization of the device at local level helps to understand the stakeholders system and how adaptable it is to situations in each of the corresponding countries and project areas. A comparative approach, based on a joint methodology of investigation and analysis, was used on four project areas: Joniškis and Ignalina in Lithuania, and Gévaudan-Lozère and Pays Coeur d’Hérault in France. It shows that, in all cases, a form of “municipalization” of the LEADER programme, or at least a strong integration of the association sector, is dominant and seems to be established. Studying the network of stakeholders helps to identify the interknowledge as well as the interdependency relationships that lie at the heart of the system. The development of the “social capital of individuals” is often an entry point, if not a cornerstone, of the stakeholders system in place. Finally, it is through the analysis of the project selection process that we can truly grasp the characteristics of the new public action mode, in particular by studying the allocation of projects in these local areas.

Pour relever les défis de l’agriculture africaine, notamment de l’autosuffisance alimentaire, de la création d’emploi et de richesse, le modèle du contrat agricole est promu par certains États et bailleurs de fonds internationaux dans le cadre d’un discours performatif sur les vertus des partenariats entre agro-industries et producteurs. Toutefois, les contrats agricoles suscitent des interprétations contradictoires. Les uns en font un modèle qui aurait des effets d’entraînement sur l’économie rurale, tandis que les autres y voient des stratégies de prédation des ressources agricoles, qui sont néfastes pour les communautés locales. D’un côté comme de l’autre, les analyses restent centrées sur des questions éthiques et parfois idéologiques. Les conditions de fonctionnement des contrats et leurs impacts en termes de développement sont peu abordés. Notre contribution, basée sur des enquêtes sociologiques menées au Sénégal, vise à caractériser objectivement les formes d’interaction (positive ou négative) entre contrats agricoles et développement des territoires qui abritent une filière rizicole. C’est à partir de ces enjeux de croisement entre développement agricole et développement territorial que nous développons une démarche méthodologique permettant de réaliser ce type de diagnostic. À l’échelle des régions dominées par la riziculture, nous mettons en exergue des trajectoires territoriales contrastées par rapport à l’interaction entre modèle agricole et développement territorial. Ce diagnostic est interprété par la connaissance des systèmes d’acteurs, notamment à l’aide de deux indicateurs, à savoir : la centralité, qui donne une indication sur les questions de gouvernance territoriale, et la densité des liens, qui renseigne sur l’importance du contrat agricole par rapport à d’autres modes de mise en relation. Concernant l’insertion des contrats agricoles, la structure des réseaux d’acteurs permet d’identifier un mode de gouvernance centralisé autour de la banque agricole nationale et de quelques industriels. Mais on note aussi une persistance des rapports informels et des structures communautaires (familles, amis, voisins) qui fonctionnent en parallèle du contrat agricole et qui remettent en cause le discours politique par rapport au potentiel transformateur des contrats agricoles.

A vidékfejlesztésnek a közös agrárpolitika (2007–2013) második pillérébe történő eredményes integrálásához a helyi szereplők kezdeményezéseire épülő közösségi tervezési módszerek elsajátítása szükséges, ami egyben a LEADER egyik célja is: alulról építkező helyi fejlesztéssel javítani a vidéki térségek helyzetét, hatékonyabbá tenni a forrásfelhasználást. Az Európai Unióban jellemzően sikeres LEADER-módszer beépült a Nemzeti Vidékfejlesztési Programba és az Új Magyarország Vidékfejlesztési Tervbe, végrehajtása a Vidékfejlesztési Minisztérium hatáskörébe tartozik. Fontos kérdés azonban, hogy a megvalósítás során a magyarországi intézményi és eljárási keretek diktálta sajátos feltételek mennyiben alkalmasak a helyi szereplők aktív részvételének ösztönzésére, a helyi demokrácia konszolidálására. Baranya megyében végzett empirikus kutatásokra építve két szempontból tárgyaljuk a helyi akciócsoportok megszervezésének és működésének kérdését: a partnerségi együttműködések összetételén és a szereplők közötti hálózatok elemzésén keresztül. Az „erős” polgármesterek – részint vállalt szerepük, részint tekintélyük okán – központi helyet foglalnak el ezekben a hálózatokban. A LEADER-tengely működését vizsgálva úgy tűnik, az önkormányzatok (jellemzően a polgármesterek) uralják a programot, és ők játszanak meghatározó szerepet az akciócsoportok partnerségi struktúrájában. Az alapelvek értelmében decentralizált, alulról építkező, az önkormányzati, a civil és a vállalkozói szféra egyenrangú partnerségére építő LEADER program magyarországi megvalósulása így a központi hatalom túlsúlya (a központosított, bürokratikus szabályozási környezet) mellett a helyi hatalom, a helyi önkormányzat dominanciájával jellemezhető.

We investigate radiation-induced effects on the DC, AC and thermal characteristics of high-performance SiGe HBTs fabricated on thin-film SOI. TCAD simulations indicate novel heavy-ion charge collection phenomena resulting from the unique [C.sub.B][E.sup.B]C device layout of this technology platform. Index Terms--C-SiGe, Heterojunction bipolar transistors, radiation effects, SiGe HBT, silicon-on-insulator (SOI), TCAD.

This paper presents a detailed investigation of the dual base method for intrinsic and extrinsic HBT's base resistance extraction that is of utmost importance for process monitoring and device modeling purpose. Ring emitter test structures layout, dc measurement conditions, and extraction methodology have been improved to get reliable results. A particular attention has been drawn to the external base resistance extraction and the effect of parasitic resistances is highlighted. The method has been generalized for an extraction of the base resistance specific parameters using any number of geometries (widths and lengths) and therefore demonstrates the base resistance scalability. This method is applied to a ST state-of-art fully self aligned double poly BiCMOS SiGeC technology, and results are discussed. Index Terms--Base resistance, bipolar modeling, dual base test structure, sheet resistance.

The technology optimization of a vertical SiGeC heterojunction bipolar transistor (HBT) on thin-film silicon-on-insulator (SOI) substrates is presented. Findings reveal fully functional devices and ideal operation for high and low collector doping.

The time invariant (TI) widely linear (WL) minimum variance distortionless response (MVDR) beamformer for the optimal reception of an unknown signal corrupted by potentially noncircular interferences is discussed. Findings reveal the suitability of the beamformer for spectrum monitoring or passive listening in noncircular context.

Three polarization diversity (PD)-2q-MUSIC algorithms depending on the a priori knowledge about the polarization of the sources are discussed. Results suggest the increase in performance of PD-2q algorithms with q when resolution in both direction of arrival and polarization is required.

An extension of the Music method to an arbitrary even order 2q (q greater than equal to 1) is proposed, giving rise to the 2q-Music methods. The performance analysis of these methods show off important results for direction-finding applications and in particular the best performance with respect to 2-Music and 4-Music, of 2q-Music method with q > 2, despite their variance, when some resolution is required.

New enlightening results about the behavior, properties, and performance of the optimal widely linear (WL) receiver for demodulation of a binary phase-shift keying (BPSK) signal corrupted by rectilinear interferences are presented. By simple algebraic operation of demodulation on the baseband signal, the minimum shift keying and Gaussian minimum shift keying (GMSK) modulations can be made to approximately correspond to a BPSK modulation allowing the application of the simple antenna interference cancellation (SAIC) concept to the GMS cellular network at the mobile level.

The Independent Component Analysis using Redundancies in the quadricovariance (ICAR) algorithm, exploiting the information contained in the data statistics at fourth order only is proposed. This algorithm allows the processing of overdetermined mixtures of sources, provided the latter have marginal fourth-order (FO) cumulants with the same sign, which is generally the case in radio communications contexts.

A new blind identification (BI) method that exploits the fourth-order data statistics only (FOBIUM) is presented to process both overdetermined and underdetermined instantaneous mixtures of statistically independent sources. The FOBIUM method is shown to require a relatively weak number of snapshots to generate good output performances for currently used radiocommunication sources, such as quadrature phase shift keying (QPSK) sources.

The mechanisms, resolution and maximal processing capacity of numerous 2qth order array processing methods are discussed. The geometry, number of Virtual Sensors (VSs) of the Virtual Array (VA) and the number of sources that could be processed by a 2qth order method by exploiting the algebraic structure of C (sub 2q,x) are controlled by the arrangement of the 2qth order data statistics.

An analysis conducted to check the behavior, and to propose adaptations of the current second-order (SO) blind source separation (BSS) methods is presented. The extension for deterministic sources like frequency shift keying (FSK) and continuous phase frequency shift keying (CPFSK) sources is proposed.

The problem is addressed of estimating second-order statistics of a frequency-selective Rayleigh channel in the context of the wideband code division multiple access (CDMA) mode of the Universal Mobile Telephone Service (UMTS). Performances are evaluated, and it is shown that significant improvement of the performance of a RAKE receiver is achieved.

Fourth-order (FO) direction finding (DF) methods have been usually employed for non-Gaussian signals. It has been shown through the use of the virtual cross-correlation (VCC) concept that the application of FO cumulants for the DF problem increases the effective aperture of an arbitrary antenna array. This led to the virtual array (VA) concept. The VA concept is presented through an alternative manner that is easier and more direct to handle than the VCC tool.

Linear-quadratic (LQ) filters for signal detection and direction-of-arrival estimation in the real case were extended to the complex plane. Specifically, an optimal second-order complex LQ array receiver for random and non-random signals was designed for the non-Gaussian case using a criterion based on the deflection or output signal-to-noise ratio. Its performance in an environment corrupted by spatially fourth-order white noise was also evaluated.

The implementation of backhauling links poses several challenges to the designers which are requested to limit the hardware costs in the framework of complex millimeter wave radio systems. This work presents a monolithically integrated E-band I/Q receiver covering the whole bandwidth from 71 to 86 GHz. The chip was implemented in a 55 nm SiGe BiCMOS technology which allows reaching a high level of integration. The receiver is based on a Low Noise Amplifier (LNA) stage and a Variable-Gain Amplifier (VGA) which provide a −11 dBm IP1dB. A double balanced mixer provides I/Q baseband outputs through a reduced-size differential phase shifter which allows to contain the chip size to 1.8 mm2. [ABSTRACT FROM AUTHOR]

This paper proposes unprecedented Expectation Propagation (EP)-based receivers for Circular Faster-Than-Nyquist (CFTN) signaling. This concept yields a Minimum Mean-Square-Error equalizer for InterSymbol Interference (ISI) processing combined with a block which we call Constellation Matcher in charge of the symbol estimates realignment with the constellation. From this framework, we explore different scheduling strategies leading to iterative EP-based receivers with our without decision feedback. Then, by extending the family of the EP process to a subset of non-circular Gaussian distributions results in a Widely Linear (WL) equalization. This new WL-EP receiver best fits the CFTN model, allowing enhanced performance at the cost of a slightly increased complexity. Also, we propose to restrict the Gaussian family to circular Gaussian distributions with identity covariance matrices up to a scaling factor. Combined with CFTN, this particular family allows a low-complexity Frequency-Domain processing of the equalization without requiring any cyclic prefix. The proposed EP-based receivers for CFTN are then evaluated for different spectral efficiencies and computational complexities. Our simulations show that they completely handle the ISI up to 5 bits/s/Hz and double the spectral efficiency compared to Nyquist signaling with almost no performance loss. [ABSTRACT FROM AUTHOR]

The use of widely linear mean square estimation (WLMSE) in statistical signal processing of complex data is better than using linear systems. In normal complex data regression is widely linear, as it is linear to both x and x* axes, where x* is a complex conjugate of x. However WLMSE should not be used where circularity is assumed. The use of WLMSE and a comparison of the MSE using widely linear and linear systems is used.

To meet the challenges of African agriculture, particularly food self-sufficiency, job creation and wealth, the agricultural contract model is being promoted by some governments and international donors in the framework of a performative discourse on the virtues of partnerships between agro-industries and producers. However, agricultural contracts give rise to contradictory interpretations. Some see it as a model that would have spillover effects on the rural economy, while others see it as a strategy of predation of agricultural resources, which is harmful to local communities. On both sides, analyses remain focused on ethical and sometimes ideological issues. The operating conditions of the contracts and their impacts in terms of development are little addressed. Our contribution, based on sociological surveys conducted in Senegal, aims at objectively characterizing the forms of interaction (positive or negative) between agricultural contracts and the development of the territories where the rice sector is located. On the basis of these issues of articulation between agricultural development and territorial development, we are proposing a methodological approach to carry out this type of diagnosis. At the scale of the regions dominated by rice growing, we highlight that the territorial trajectories are contrasted in relation to the interaction between the agricultural model and territorial development. This diagnosis is interpreted through the knowledge of the systems of actors, in particular with the help of two indicators, namely centrality, which gives an indication of the issues of territorial governance, and the density of social relations, which provides information on the importance of the agricultural contract in relation to other modes of relationship building. With regard to the insertion of agricultural contracts, the structure of the networks of actors makes it possible to identify a centralized mode of governance at the level of the national agricultural bank and a few agro-industrial enterprises. Nevertheless, informal relationships and traditional local structures (families, friends, neighbors) persist and function in parallel with the agricultural contract, calling into question the political discourse regarding the transformative potential of agricultural contracts. [ABSTRACT FROM AUTHOR]

Maximum oscillation frequency (${f}_{\textit {MAX}}$) of mm-wave transistors is one of the key figures of merit (FOMs) for evaluating the HF-performance of a given technology. However, accurate measurements of ${f}_{\textit {MAX}}$ are very difficult. Determination of ${f}_{\textit {MAX}}$ is significantly affected by the measurement uncertainties in the admittance (${y}$) parameters. In order to get rid of the random measurement error and to obtain a reliable and stable ${f}_{\textit {MAX}}$ value, the frequency dependent ${y}$ -parameters are described by rational functions formulated from the small-signal hybrid ${\pi }$ -model of the transistor under investigation. The parameters of these functions are determined following a least square error technique that minimizes the functional error with the measured data. The approach is especially useful for a fast and reliable evaluation of ${f}_{\textit {MAX}}$ value. Devices from two different SiGe and an FDSOI (Fully Depleted Silicon On Insulator) MOS technology are measured and stable ${f}_{\textit {MAX}}$ values are estimated following this approach. [ABSTRACT FROM AUTHOR]

The synchronization and/or time acquisition problem in the presence of interferences has been strongly studied these last two decades, mainly to mitigate the multiple access interferences from other users in DS/CDMA systems. Among the available receivers, only some scarce receivers may also be used in other contexts such as F/TDMA systems. However, these receivers assume implicitly or explicitly circular (or proper) interferences and become suboptimal for noncircular (or improper) interferences. Such interferences are characteristic in particular of radio communication networks using either rectilinear (or monodimensional) modulations such as BPSK modulation or modulation becoming quasirectilinear after a preprocessing such as MSK, GMSK, or OQAM modulations. For this reason, the purpose of this paper is to introduce and to analyze the performance of second-optimal array receivers for synchronization and/or time acquisition of BPSK, MSK, and GMSK signals corrupted by noncircular interferences. For given performances and in the presence of rectilinear signal and interferences, the proposed receiver allows a reduction of the number of sensors by a factor at least equal to two.

In this article, the electrical model of a millimeter-wave (mmW), silicon-based noise source is developed in the frequency range up to 325 GHz. The model is studied as a function of the biasing current and the structure size. The noise source is based on a Schottky diode realized on the 55-nm SiGe BiCMOS technology from STMicroelectronics, Crolles, France. Due to the ability of being integrated on silicon, this noise source can be used for high-frequency in situ noise characterization of advanced silicon CMOS or bipolar technologies in the mmW range. In previous study, the diode was used as a noise source when biased near the avalanche regime, and an excess noise ratio (ENR) up to 20 dB has been achieved in a frequency range up to 260 GHz. In this article, the ENR value of the diode is retrieved from the electrical model and compared to the value extracted by measurements. The extracted ENR value was also studied for several diode sizes and biasing currents and measured up to 325 GHz, with a good agreement with the modeling. [ABSTRACT FROM AUTHOR]

A 240-GHz direct conversion I–Q receiver with 74-GHz RF bandwidth is reported. It features a mixer-first architecture with fundamental local oscillator (LO)-frequency Gilbert-cell downconversion mixers, variable-gain baseband amplifiers, and a 240-GHz LO source, making it the first fully integrated 240-GHz I–Q receiver. With a phase noise of −82 dBc/Hz at 1-MHz offset, the LO source has a 27-GHz tuning range and consists of a 120-GHz voltage-controlled oscillator (VCO), a frequency doubler, and a static divide-by-128 chain. The measured peak downconversion gain is 23 dB and is adjustable over 38 dB. Along with the IF bandwidth of 59 GHz, the wide RF bandwidth makes it suitable for both high data-rate communication and emerging quantum computing applications. The chip occupies an area of 1.837 mm2 and consumes 859 mW. [ABSTRACT FROM AUTHOR]