341 |
Le pluralisme juridique international : contribution des juges internationaux à la mise en cohérence du droit international / International Legal Pluralism : Contribution of International Judges to the Consistency of International LawClaeys-Broutin, Odile 07 December 2011 (has links)
Le droit international évolue et se traduit par une augmentation des normes, des organisations et des juridictions internationales, faisant craindre une fragmentation du droit international au sein de l’ordre juridique international. L’ordre juridique international s’entend, au sens large, comme le droit international régissant la société internationale. Celui-ci englobe les ordres juridiques internationaux spécialisés, composés des organisations internationales. Chacune d’entre elles comprend une juridiction ou un tribunal arbitral. La problématique de cette thèse est de déterminer, par l’étude du pluralisme juridique international, si ce risque de fragmentation du droit international est avéré ou non. Elle se fonde, pour ce faire, sur une analyse systémique des ordres juridiques internationaux, pour établir si ceux-ci établissent des rapports de droit entre eux, ainsi que sur une analyse normative des ordres juridiques, afin de déterminer si chacun d’entre eux a une cohérence propre. Dans une première partie, il est démontré que le pluralisme juridique international semble désordonné, induisant un risque de fragmentation du droit international, en raison, d’une part, de la multiplication des ordres juridiques internationaux et, d’autre part, de leur carence institutionnelle. Il est démontré ensuite, dans une seconde partie, que le pluralisme juridique international s’ordonne grâce à la mise en cohérence du droit international par les juges internationaux. Ceux-ci coordonnent la jurisprudence internationale grâce à leur jurisdictio (dire le droit) et érigent un véritable pouvoir juridictionnel international à travers leur imperium (rendre une décision obligatoire). / International law evolves at a rapid pace, and results in a strong increase in norms, organizations and international courts, raising increasing fears about a fragmentation of international law within the international legal order itself. The international legal order is defined, in the broadest sense of the term, as international law aimed at governing international society. This includes specialized international legal systems, made up of a number of international organizations ; each one including a court or an arbitral tribunal. The aim of this thesis is to determine, through the study of international legal pluralism, weather this foreseen risk of a possible fragmentation of the international law is, in the end, proven or not. In order to fulfill this aim, our work is based, on the one hand, on a systemic analysis of international legal orders, this in order to determine whether these bodies establish legal relationships between themselves, and on the other hand, on a normative analysis of legal systems, to determine this time whether each one sets up, or not, its proper inner coherence.In the first part, we show that the international legal pluralism seems to be uncoordinated, inducing a risk of fragmentation of international law, this due, in part, to the proliferation of international legal orders and, and in other part, to their lack of institutional ground. In the second part, we aim at proving that the international legal pluralism finds best its balance when international law is put into practice by international judges. They coordinate international jurisprudence through their jurisdictio (apply the law) and set out the boundaries of a true international judicial power through their imperium (to pronounce a binding decision).
|
342 |
Intersection arithmétique et problème de Lehmer elliptique / Lehmer's problem and arithmetic intersectionWinckler, Bruno 20 November 2015 (has links)
Cette thèse étudie le problème de minoration de la hauteur canonique sur les courbeselliptiques. Son résultat diophantien principal utilise des méthodes d’intersectionarithmétique pour retrouver un résultat de Laurent, qui démontrait la conjecturede Lehmer pour les courbes elliptiques à multiplications complexes à un exposant" près, tout en explicitant complètement sa dépendance en divers paramètres liésà la courbe elliptique ; une telle démarche peut être motivée par la conjecture deLang, qui présage une minoration possible de la hauteur canonique proportionnelle,essentiellement, à la hauteur de Faltings de la courbe.Notre dissertation commence toutefois par une partie dédiée à l’explicitation duthéorème de densité de Chebotarev, qui reprend les grandes lignes d’un travail deLagarias et Odlyzko, et s’avère être cruciale dans notre approche du problème deLehmer elliptique. On obtient également des majorations des zéros de Siegel et de lanorme du plus petit idéal premier entrant en jeu dans le théorème de Chebotarev. / In this thesis we consider the problem of lower bounds for the canonical height onelliptic curves, aiming for the conjecture of Lehmer. Our main diophantine result isan explicit version of a theorem of Laurent (who proved this conjecture for ellipticcurves with CM up to a " exponent) using arithmetic intersection, enlightening thedependence with parameters linked to the elliptic curve ; such a result can be motivatedby the conjecture of Lang, hoping for a lower bound proportional to, roughly,the Faltings height of the curve.Nevertheless, our dissertation begins with a part dedicated to a completely explicitversion of the density theorem of Chebotarev, along the lines of a previous workdue to Lagarias and Odlyzko, which will be crucial to investigate the elliptic Lehmerproblem. We also obtain upper bounds for Siegel zeros, and for the smallest primeideal whose Frobenius is in a fixed conjugacy class.
|
343 |
Elliptic curve cryptography algorithms resistant against power analysis attacks on resource constrained devices / Algorithmes cryptographiques à base de courbes elliptiques résistant aux attaques par analyse de consommationHoussain, Hilal 21 December 2012 (has links)
Les systèmes de cryptographie à base de courbe elliptique (ECC) ont été adoptés comme des systèmes standardisés de cryptographie à clé publique (PKC) par l'IEEE, ANSI, NIST, SEC et WTLS. En comparaison avec la PKC traditionnelle, comme RSA et ElGamal, l'ECC offre le même niveau de sécurité avec des clés de plus petites tailles. Cela signifie des calculs plus rapides et une consommation d'énergie plus faible ainsi que des économies de mémoire et de bande passante. Par conséquent, ECC est devenue une technologie indispensable, plus populaire et considérée comme particulièrement adaptée à l’implémentation sur les dispositifs à ressources restreintes tels que les réseaux de capteurs sans fil (WSN). Le problème majeur avec les noeuds de capteurs chez les WSN, dès qu'il s'agit d’opérations cryptographiques, est les limitations de leurs ressources en termes de puissance, d'espace et de temps de réponse, ce qui limite la capacité du capteur à gérer les calculs supplémentaires nécessaires aux opérations cryptographiques. En outre, les mises en oeuvre actuelles de l’ECC sur WSN sont particulièrement vulnérables aux attaques par canaux auxiliaires (SCA), en particulier aux attaques par analyse de consommation (PAA), en raison de l'absence de la sécurité physique par blindage, leur déploiement dans les régions éloignées et le fait qu’elles soient laissées sans surveillance. Ainsi, les concepteurs de crypto-processeurs ECC sur WSN s'efforcent d'introduire des algorithmes et des architectures qui ne sont pas seulement résistants PAA, mais également efficaces sans aucun supplément en termes de temps, puissance et espace. Cette thèse présente plusieurs contributions dans le domaine des cryptoprocesseurs ECC conscientisés aux PAA, pour les dispositifs à ressources limitées comme le WSN. Premièrement, nous proposons deux architectures robustes et efficaces pour les ECC conscientisées au PAA. Ces architectures sont basées sur des algorithmes innovants qui assurent le fonctionnement de base des ECC et qui prévoient une sécurisation de l’ECC contre les PAA simples (SPA) sur les dispositifs à ressources limitées tels que les WSN. Deuxièmement, nous proposons deux architectures additionnelles qui prévoient une sécurisation des ECC contre les PAA différentiels (DPA). Troisièmement, un total de huit architectures qui incluent, en plus des quatre architectures citées ci-dessus pour SPA et DPA, deux autres architectures dérivées de l’architecture DPA conscientisée, ainsi que deux architectures PAA conscientisées. Les huit architectures proposées sont synthétisées en utilisant la technologie des réseaux de portes programmables in situ (FPGA). Quatrièmement, les huit architectures sont analysées et évaluées, et leurs performances comparées. En plus, une comparaison plus avancée effectuée sur le niveau de la complexité du coût (temps, puissance, et espace), fournit un cadre pour les concepteurs d'architecture pour sélectionner la conception la plus appropriée. Nos résultats montrent un avantage significatif de nos architectures proposées par rapport à la complexité du coût, en comparaison à d'autres solutions proposées récemment dans le domaine de la recherche. / Elliptic Curve Cryptosystems (ECC) have been adopted as a standardized Public Key Cryptosystems (PKC) by IEEE, ANSI, NIST, SEC and WTLS. In comparison to traditional PKC like RSA and ElGamal, ECC offer equivalent security with smaller key sizes, in less computation time, with lower power consumption, as well as memory and bandwidth savings. Therefore, ECC have become a vital technology, more popular and considered to be particularly suitable for implementation on resource constrained devices such as the Wireless Sensor Networks (WSN). Major problem with the sensor nodes in WSN as soon as it comes to cryptographic operations is their extreme constrained resources in terms of power, space, and time delay, which limit the sensor capability to handle the additional computations required by cryptographic operations. Moreover, the current ECC implementations in WSN are particularly vulnerable to Side Channel Analysis (SCA) attacks; in particularly to the Power Analysis Attacks (PAA), due to the lack of secure physical shielding, their deployment in remote regions and it is left unattended. Thus designers of ECC cryptoprocessors on WSN strive to introduce algorithms and architectures that are not only PAA resistant, but also efficient with no any extra cost in terms of power, time delay, and area. The contributions of this thesis to the domain of PAA aware elliptic curve cryptoprocessor for resource constrained devices are numerous. Firstly, we propose two robust and high efficient PAA aware elliptic curve cryptoprocessors architectures based on innovative algorithms for ECC core operation and envisioned at securing the elliptic curve cryptoprocessors against Simple Power Analysis (SPA) attacks on resource constrained devices such as the WSN. Secondly, we propose two additional architectures that are envisioned at securing the elliptic curve cryptoprocessors against Differential Power Analysis (DPA) attacks. Thirdly, a total of eight architectures which includes, in addition to the two SPA aware with the other two DPA awareproposed architectures, two more architectures derived from our DPA aware proposed once, along with two other similar PAA aware architectures. The eight proposed architectures are synthesized using Field Programmable Gate Array (FPGA) technology. Fourthly, the eight proposed architectures are analyzed and evaluated by comparing their performance results. In addition, a more advanced comparison, which is done on the cost complexity level (Area, Delay, and Power), provides a framework for the architecture designers to select the appropriate design. Our results show a significant advantage of our proposed architectures for cost complexity in comparison to the other latest proposed in the research field.
|
344 |
Binary Arithmetic for Finite-Word-Length Linear Controllers : MEMS Applications / Intégration sur électronique dédiée et embarquée du traitement du signal et de la commande pour les microsystemes appliqués à la microrobotiqueOudjida, Abdelkrim Kamel 20 January 2014 (has links)
Cette thèse traite le problème d'intégration hardware optimale de contrôleurs linéaires à taille de mot finie, dédiés aux applications MEMS. Le plus grand défi est d'assurer des performances de contrôle satisfaisantes avec un minimum de ressources logiques. Afin d'y parvenir, deux optimisations distinctes mais complémentaires peuvent être entreprises: en théorie de contrôle et en arithmétique binaire. Seule cette dernière est considérée dans ce travail.Comme cette arithmétique cible des applications MEMS, elle doit faire preuve de vitesse afin de prendre en charge la dynamique rapide des MEMS, à faible consommation de puissance pour un contrôle intégré, hautement re-configurabe pour un ajustement facile des performances de contrôle, et facilement prédictible pour fournir une idée précise sur les ressources logiques nécessaires avant l'implémentation même.L'exploration d'un certain nombre d'arithmétiques binaires a montré que l'arithmétique radix-2r est celle qui répond au mieux aux exigences précitées. Elle a été pleinement exploitée afin de concevoir des circuits de multiplication efficaces, qui sont au fait, le véritable moteur des systèmes linéaires.L'arithmétique radix-2r a été appliquée à l'intégration hardware de deux structures linéaires à taille de mot finie: un contrôleur PID variant dans le temps et à un contrôleur LQG invariant dans le temps,avec un filtre de Kalman. Le contrôleur PID a montré une nette supériorité sur ses homologues existants. Quant au contrôleur LQG, une réduction très importante des ressources logiques a été obtenue par rapport à sa forme initiale non optimisée / This thesis addresses the problem of optimal hardware-realization of finite-word-length(FWL) linear controllers dedicated to MEMS applications. The biggest challenge is to ensuresatisfactory control performances with a minimal hardware. To come up, two distinct butcomplementary optimizations can be undertaken: in control theory and in binary arithmetic. Only thelatter is involved in this work.Because MEMS applications are targeted, the binary arithmetic must be fast enough to cope withthe rapid dynamic of MEMS; power-efficient for an embedded control; highly scalable for an easyadjustment of the control performances; and easily predictable to provide a precise idea on therequired logic resources before the implementation.The exploration of a number of binary arithmetics showed that radix-2r is the best candidate that fitsthe aforementioned requirements. It has been fully exploited to designing efficient multiplier cores,which are the real engine of the linear systems.The radix-2r arithmetic was applied to the hardware integration of two FWL structures: a linear timevariant PID controller and a linear time invariant LQG controller with a Kalman filter. Both controllersshowed a clear superiority over their existing counterparts, or in comparison to their initial forms.
|
345 |
Calcul flottant haute performance sur circuits reconfigurables / High-performance floating-point computing on reconfigurable circuitsPasca, Bogdan Mihai 21 September 2011 (has links)
De plus en plus de constructeurs proposent des accélérateurs de calculs à base de circuits reconfigurables FPGA, cette technologie présentant bien plus de souplesse que le microprocesseur. Valoriser cette flexibilité dans le domaine de l'accélération de calcul flottant en utilisant les langages de description de circuits classiques (VHDL ou Verilog) reste toutefois très difficile, voire impossible parfois. Cette thèse a contribué au développement du logiciel FloPoCo, qui offre aux utilisateurs familiers avec VHDL un cadre C++ de description d'opérateurs arithmétiques génériques adapté au calcul reconfigurable. Ce cadre distingue explicitement la fonctionnalité combinatoire d'un opérateur, et la problématique de son pipeline pour une précision, une fréquence et un FPGA cible donnés. Afin de pouvoir utiliser FloPoCo pour concevoir des opérateurs haute performance en virgule flottante, il a fallu d'abord concevoir des blocs de bases optimisés. Nous avons d'abord développé des additionneurs pipelinés autour des lignes de propagation de retenue rapides, puis, à l'aide de techniques de pavages, nous avons conçu de gros multiplieurs, possiblement tronqués, utilisant des petits multiplieurs. L'évaluation de fonctions élémentaires en flottant implique souvent l'évaluation en virgule fixe d'une fonction. Nous présentons un opérateur générique de FloPoCo qui prend en entrée l'expression de la fonction à évaluer, avec ses précisions d'entrée et de sortie, et construit un évaluateur polynomial optimisé de cette fonction. Ce bloc de base a permis de développer des opérateurs en virgule flottante pour la racine carrée et l'exponentielle qui améliorent considérablement l'état de l'art. Nous avons aussi travaillé sur des techniques de compilation avancée pour adapter l'exécution d'un code C aux pipelines flexibles de nos opérateurs. FloPoCo a pu ainsi être utilisé pour implanter sur FPGA des applications complètes. / Due to their potential performance and unmatched flexibility, FPGA-based accelerators are part of more and more high-performance computing systems. However, exploiting this flexibility for accelerating floating-point computations by manually using classical circuit description languages (VHDL or Verilog) is very difficult, and sometimes impossible. This thesis has contributed to the development of the FloPoCo software, a C++ framework for describing flexible FPGA-specific arithmetic operators. This framework explicitly separates the description of the combinatorial functionality of an arithmetic operator, and its pipelining for a given precision, operating frequency and target FPGA.In order to be able to use FloPoCo for designing high performance floating-point operators, we first had to design the optimized basic blocks. We first developed pipelined addition architectures exploiting the fast-carry lines present in modern FPGAs. Next, we focused on multiplication architectures. Using tiling techniques, we proposed novel architectures for large multipliers, but also truncated multipliers, based on the multipliers found in modern FPGA DSP blocks. We also present a generic FloPoCo operator which inputs the expression of a function, its input and output precisions, and builds an optimized polynomial evaluator for the fixed-point evaluation of this function. Using this building block we have designed floating-point operators for the square-root and exponential functions which significantly outperform existing operators. Finally, we also made use of advanced compilation techniques for adapting the execution of a C program to the flexible pipelines of our operators.
|
346 |
Multiple Constant Multiplication Optimization Using Common Subexpression Elimination and Redundant NumbersAl-Hasani, Firas Ali Jawad January 2014 (has links)
The multiple constant multiplication (MCM) operation is a fundamental operation in digital signal processing (DSP) and digital image processing (DIP). Examples of the MCM are in finite impulse response (FIR) and infinite impulse response (IIR) filters, matrix multiplication, and transforms.
The aim of this work is minimizing the complexity of the MCM operation using common subexpression elimination (CSE) technique and redundant number representations. The CSE technique searches and eliminates common digit patterns (subexpressions) among MCM coefficients. More common subexpressions can be found by representing the MCM coefficients using redundant number representations.
A CSE algorithm is proposed that works on a type of redundant numbers called the zero-dominant set (ZDS). The ZDS is an extension over the representations of minimum number of non-zero digits called minimum Hamming weight (MHW). Using the ZDS improves CSE algorithms' performance as compared with using the MHW representations. The disadvantage of using the ZDS is it increases the possibility of overlapping patterns (digit collisions). In this case, one or more digits are shared between a number of patterns. Eliminating a pattern results in losing other patterns because of eliminating the common digits. A pattern preservation algorithm (PPA) is developed to resolve the overlapping patterns in the representations.
A tree and graph encoders are proposed to generate a larger space of number representations. The algorithms generate redundant representations of a value for a given digit set, radix, and wordlength. The tree encoder is modified to search for common subexpressions simultaneously with generating of the representation tree. A complexity measure is proposed to compare between the subexpressions at each node. The algorithm terminates generating the rest of the representation tree when it finds subexpressions with maximum sharing. This reduces the search space while minimizes the hardware complexity.
A combinatoric model of the MCM problem is proposed in this work. The model is obtained by enumerating all the possible solutions of the MCM that resemble a graph called the demand graph. Arc routing on this graph gives the solutions of the MCM problem. A similar arc routing is found in the capacitated arc routing such as the winter salting problem. Ant colony optimization (ACO) meta-heuristics is proposed to traverse the demand graph. The ACO is simulated on a PC using Python programming language. This is to verify the model correctness and the work of the ACO. A parallel simulation of the ACO is carried out on a multi-core super computer using C++ boost graph library.
|
347 |
A study of the dynamics of developing sustained church planting movements in Asian nations, based on lessons learned in the 2004-2005 NEXT conferences in East AsiaSmith, Stephen Robert 30 November 2007 (has links)
This study attempts to be an exhaustive analysis of the dynamics of developing sustained
church planting movements in Asian nations, based on lessons learned in the 2004-2005
NEXT conferences in East Asia. Principles are being discovered and methodologies developed
in East Asia on how to build sustained church planting movements around the world.
To understand these, consolidate learning, and apply that learning in a variety of crosscultural
ministry contexts, a series of conferences were hosted by my wife and myself. Eight
week-long ”NEXT conferences” were held, consisting of sixty experienced strategy coordinators
plus eleven regional supervisors, to wrestle with these issues. This paper is based on
the findings of these conferences; specifically, that there are divine principles and particular
methodologies which enable missionaries to cooperate with the Holy Spirit in developing
sustained church planting movements that saturate ethno-linguistic people groups and cities
of Asia, and ultimately, the rest of the world. / Christian Spirituality, Church History and Missiology) / M.Th. (Missiology)
|
348 |
An evaluation of Training for Trainers (T4T) as an aid for developing sustained church planting movements (CPMs)Smith, Stephen Robert 09 1900 (has links)
This paper attempts to evaluate Training for Trainers (T4T) as an aid for developing healthy and sustained church planting movements (CPMs). The thesis is that Training for Trainers (T4T) can enable and sustain (by the Spirit’s power) healthy church planting movements because a discipleship process is built into the methodology that develops believers
in their personal and communal growth and equips them to repeat the process with other individuals they reach. The very format of the T4T process provides a context for developing disciples inwardly and training disciples to minister outwardly. The T4T process continues over the course of months and years to systematically move believers through the
essential stages of sustained church planting movements:
Bridges in conversations with the lost from non-spiritual topics to the gospel in order to find those God is preparing (knowing whom to talk to and how to start)
• Reproducible evangelism methods that are effective in the local context and can be learned by any new believer
• Reproducible discipleship that addresses both short-term and long-term spiritual
growth in a manner appropriate to the local worldview and able to be passed on by a new believer
• Reproducible church models appropriate to the local context and able to be led and passed on by new believers
• Leadership development and multiplication patterns that develop leaders rapidly in the context of ministry and enable the number of leaders to keep pace with the number of new churches.
T4T moves each new generation of disciples (trainers) and churches through this process because it casts vision for and gives loving accountability for disciples to truly become trainers of others. It does this primarily through a three-thirds training process. T4T is training
for trainers who will train trainers who will train trainers. T4T attempts to initiate movements of God in which at least four generations of new disciples and churches emerge. This paper evaluates T4T is based on case studies, survey instruments and biblical principles and then offers recommendations for CPM practitioners. / Christian Spirituality, Church History and Missiology / D. Th. (Missiology)
|
349 |
Ocorrência natural de sexuados, produção in vitro de rainhas e multiplicação de colônias em Tetragonisca augustula (Hymenoptera, Apidae, Meliponini) / Natural occurrence of sexuals, production in vitro of queens and colony multiplication in Tetragonisca angustula (Hymenoptera, Apidae, Meliponini).Prato, Mauro 04 February 2011 (has links)
Com o avanço da meliponicultura, a utilização das abelhas sem ferrão, assim como de seus subprodutos, tem abrangido novas áreas, como a polinização de culturas agrícolas. Assim, a demanda pelo aumento do número de colônias tem sido constante, porém devido ao pouco conhecimento sobre a biologia reprodutiva dessas abelhas, há dificuldade de produção de colônias em larga escala, acarretando uma séria limitação quanto à utilização comercial desses polinizadores. Buscamos com este trabalho, oferecer ferramentas que possibilitem a multiplicação de colônias de abelhas sem ferrão em grande quantidade em um curto período de tempo. Nas abelhas indígenas sem ferrão (exceto no gênero Melipona e nos casos onde ocorrem rainhas-miniatura) a quantidade de alimento ingerido pelas larvas fêmeas é o fator responsável pela diferenciação das castas, pois as larvas que se tornam rainhas ingerem mais alimento que as larvas de futuras operárias, não havendo diferença qualitativa entre o alimento fornecido às larvas que originarão ambas as castas. De acordo com este modelo de determinação de castas, buscamos estabelecer a produção in vitro de rainhas em Tetragonisca angustula oferecendo maior quantidade de alimento às larvas de operárias, induzindo seu desenvolvimento em rainhas, que após a emergência foram introduzidas em mini-colônias órfãs para verificação da sua viabilidade (fecundação natural e postura de ovos). Em condições naturais as larvas de T. angustula que se tornam rainhas e operárias recebem respectivamente 55 µL e 8 µL de alimento em média. Assim, para a produção in vitro de rainhas oferecemos 55 µL de alimento a larvas de operárias coletadas em estágio pré-alimentação de ninhos naturais e conseguimos uma taxa de sobrevivência de até 51% e de 19% na obtenção de rainhas fisiogástricas, configurando um avanço em relação à taxa natural de emergência de rainhas, que foi de 0,21%. Das mini-colônias onde foram introduzidas rainhas virgens, 41% tiveram sucesso e se tornaram colônias perenes. A utilização de larvas de operárias na produção in vitro de rainhas é possível devido ao fato de as larvas serem totipotentes, assim como a utilização de alimento coletado de células de cria de operárias/machos, pois os resultados das análises comparativas do conteúdo protéico e de aminoácidos totais e livres dos alimentos contidos em células de cria de operárias/machos e células reais mostraram não haver diferenças significativas. A utilização de alimento larval de Scaptotrigona aff. depilis na criação in vitro de rainhas de T. angustula mostrou a possibilidade de produção de rainhas viáveis com esta nova técnica embora os perfis protéicos dos alimentos larvais de ambas as espécies sejam diferentes. Os experimentos de produção in vitro de rainhas com diferentes quantidades de alimento oferecido às larvas mostraram a existência de uma quantidade limite de alimento entre 35 µL e 45 µL acima da qual todos os indivíduos se tornam rainhas e abaixo da qual todos se tornam operárias, não havendo a ocorrência de indivíduos intermediários (intercastas). Introduzindo as rainhas produzidas in vitro em mini-colônias órfãs, conseguimos o estabelecimento de 16 colônias perenes a partir de seis colônias doadoras de material no período de seis meses, o que configura um avanço de 33% em relação às técnicas tradicionais de multiplicação de colônias que conseguiriam formar, no máximo, 12 colônias no mesmo período. A verificação da freqüência de produção de sexuados nas colônias naturais ao longo do ano mostrou que os machos são produzidos sazonalmente com alta taxa no período de fevereiro a abril, e embora as rainhas possuam uma produção baixa e homogênea ao longo do ano, concluímos que aquelas produzidas no período onde ocorre maior disponibilidade de machos possuem maiores chances de serem fecundadas. Assim, foi extremamente importante sincronizar a produção in vitro de rainhas com o período de maior disponibilidade de machos, uma vez que a fecundação destas ocorreu naturalmente. A produção in vitro de rainhas e a multiplicação de colônias nas abelhas sem ferrão se tornam ferramentas importantes para as técnicas de manejo que visam obter colônias em larga escala, com emprego na polinização, meliponicultura e conservação. / With the improvement of meliponiculture, the use of stingless bees, as well as their byproducts, has comprised new areas, such as the pollination of crops. Thus, the requirement by increasing the number of colonies has been constant, but due to poor knowledge about reproductive biology of these bees, have been difficult produce colonies on a large scale, what causes serious limitations on the commercial use of these pollinators. Our goals were to offer tools that allowed the multiplication of stingless bees colonies in large quantities in a short time. In stingless bees (except in the genus Melipona and in cases where there are miniature-queens) the amount of food ingested by female larvae is the responsible feature for caste differentiation, because the larvae that will become queens must to ingest more food than the larvae of future workers, and there is no qualitative difference between the food provided to larvae of both castes. According to this model of caste determination, we aimed at to establish the in vitro production of queens in Tetragonisca angustula, offering a large quantity of larval food to the workers larvae, thus inducing their development into queens that after rearing were introduced in orphaned mini-colonies to verify their feasibility (natural mating and egg laying). Under natural conditions the larvae of T. angustula that become queens and workers receive respectively, 55 µL and 8 µL of food on average. Thus, for the in vitro production of queens we offered 55 µL of food to workers larvae collected in pre-feeding stage from natural nests and we were able to get a survival rate up to 51 % and 19% in obtaining viable queens, which is an improvement compared to 0,21% of rearing queens observed in natural hives. About 41% of mini-colonies, where viable queens were introduced were successful and have become perennial colonies. The use of workers larvae on in vitro production of queens is possible because the larvae are totipotent, as well as the use of food collected from workers/males brood cells, because the results of comparative analysis of protein content and total and free amino acids of food stored in worker/males brood cells and royal cells showed no significant differences. The use of larval food from Scaptotrigona aff. depilis on in vitro rearing of T. angustula queens showed the possibility of producing viable queens, with this new technique, although the protein profiles of larval food of both species were different. The experiments of in vitro production of queens with different amounts of food offered to the larvae showed the existence of a threshold quantity of food between 35 mL and 45 mL above which all individuals become queens and below which all individuals become workers, without the occurrence of intermediate individuals (intercaste). Inserting the queens produced in vitro in orphaned mini-colonies, we were able to establish 16 perennial colonies as from six colonies donors of material in six months, constituting an increase of 33% compared to traditional techniques of multiplication of colonies which would form up only 12 colonies in the same period. Verification of frequency of sexuals reared in natural colonies over the year showed that males are produced seasonally with high rate in the period from February to April, and although the queens have a low and homogeneous occurrence over the year, we concluded that the queens produced during the period where there is greater availability of males, have higher chances of being fertilized. Thus, was extremely important synchronize the in vitro production of queens with the period where there is greater availability of males, since fertilization of these queens occurred naturally. The in vitro production of queens and multiplication of colonies in stingless bees become important tools for handling techniques that aim to obtain colonies on a large scale, with employment in pollination, meliponiculture and conservation.
|
350 |
La fragmentation du droit international public : l'oeuvre de codification à la lumière de la fragmentation du droit international / The fragmentation of international law : the codification of international law in the light of its fragmentationMoundounga Ntsigou, Serge 25 January 2013 (has links)
Le phénomène de fragmentation reste assez complexe et se trouve mêlé à celui d’internormativité en ce sens qu’il englobe l’étude de la relation entre droit et société et, notamment, le droit international en tant que système juridique. La présente étude constitue, de manière générale, un essai sur l’œuvre de codification et de développement du droit international, en prenant en compte les récentes évolutions du droit international symbolisés dans ce que l’on qualifie, de plus en plus, de fragmentation du droit international. L’hypothèse gravite autour de l’extraordinaire expansion que connait cette discipline depuis près de cinquante ans et des changements survenus au niveau de ce qu’on appelle communément la « Communauté internationale ». L’intérêt est suscité par l’évolution des méthodes d’élaboration des normes du droit international, notamment du fait de la multiplication des organes compétents de l’ONU et le besoin de trouver des solutions pratiques au phénomène des conflits normatifs au niveau international. Ce sont là les deux conséquences (législative et institutionnelle) du phénomène de fragmentation qui menacent aujourd’hui l’ordre juridique international et l’unité du droit international. Il semble donc normal, compte tenu de cette situation, que se produise un nouvel essor de l’idée de codification du droit international. / The phenomenon of fragmentation is quite complex and is involved in the phenomenon of internormativity in so much as it includes the study of the relationship between law and society and, in particular, international law as a legal system. This study is, as a general, an essay on the work of codification and progressive development of international law as embodied in the practice of the International Law Commission, taking into account recent developments in international law symbolized in what is termed, increasingly, fragmentation of international law. The case revolves around the extraordinary expansion that this discipline has being knowing for nearly fifty years now and around the changes affecting what is commonly called the ‘international community’. The interest is generated by the evolution of methods for the development of international law, owing in particular to the multiplication of the competent organs of the UN and the need to find practical solutions to the phenomenon of normative conflicts at the international level. These are two consequences (legal and institutional) of the phenomenon of fragmentation that now has come to threaten the international legal order and the unity of international law. Therefore, given this situation, the need for a strengthening of the concept of codification of international.
|
Page generated in 0.0421 seconds