Telecommunication industry in national legal norm must be able to provide lawful interception functions of offenders phone. The traditional PSTN and GSM have had such a system that can provide investigating authorities to monitor telephone and mobile phone users. In the meanwhile, IP telephony must provide the same monitor functions. However, the current SIP-based IP telephony is still unable to provide this monitoring function. In my thesis, I designed and implemented a monitoring system structure over SIP. It can efficiently carry out lawful interception without violating SIP communication. Additionally, it will not cause any overload on server, but will be able to monitor immediately. The recorded data can be played back without any delay and distortion. A database is built up first for those who are monitored. When SIP dialog begins, SIP proxy inspects whether a call must be monitored. If it is the case of monitoring, a duplicate packet flow is delivered to the monitor. The monitor can playback. I believe this implementation can become a platform for further work in the lawful interception.

Nous avons proposé des mécanismes pour mettre en œuvre la mémoïsation de fonction au niveau logiciel dans le cadre de nos efforts pour améliorer les performances du code séquentiel. Nous avons analysé le potentiel de la mémoïsation de fonction sur des applications et le gain de performance qu'elle apporte sur des architectures actuelles. Nous avons proposé trois approches - une approche simple qui s'applique au chargement et qui fonctionne pour toute fonction de bibliothèque liée dynamiquement, une approche à la compilation utilisant LLVM qui peut permettre la mémoïsation pour toute fonction du programme, ainsi qu'une proposition d'implémentation de la mémoïsation en matériel et ses avantages potentiels. Nous avons démontré avec les fonctions transcendantales que l'approche au chargement est applicable et donne un bon avantage, même avec des architectures et des compilateurs (avec la restriction qu'elle ne peut être appliquée que pour les fonctions liées dynamiquement) modernes. Notre approche à la compilation étend la portée de la mémoïsation et en augmente également les bénéfices. Cela fonctionne pour les fonctions définies par l’utilisateur ainsi que pour les fonctions de bibliothèque. Nous pouvons gérer certains types de fonctions non pures comme les fonctions avec des arguments de type pointeur et l'utilisation de variables globales. La mémoïsation en matériel abaisse encore le seuil de profitabilité de la mémoïsation et donne plus de gain de performance en moyenne. / We have proposed mechanisms to implement function memoization at a software level as part of our effort to improve sequential code performance. We have analyzed the potential of function memoization on applications and its performance gain on current architectures. We have proposed three schemes - a simple load time approach which works for any dynamically linked function, a compile time approach using LLVM framework which can enable memoization for any program function and also a hardware proposal for doing memoization in hardware and its potential benefits. Demonstration of the link time approach with transcendental functions showed that memoization is applicable and gives good benefit even under modern architectures and compilers (with the restriction that it can be applied only for dynamically linked functions). Our compile time approach extends the scope of memoization and also increases the benefit due to memoization. This works for both user defined functions as well as library functions. It can handle certain kind of non pure functions like those functions with pointer arguments and global variable usage. Hardware memoization lowers the threshold for a function to be memoized and gives more performance gain on average.

In farming of fruit trees it is of interest to know the light interception of the trees. Therefore, in this project, a geometric model of the trees was derived using LiDAR data and this was combined with a sky model to estimate the light interceptionof orchard trees. The light interception was estimated by first synthesising a discrete model of the hemispherical sky, which holds a measure of global lightradiation in each node. The light interception of the trees was then estimated by ray tracing from the sky, applying a radiation absorption model where rays passed the point cloud representation of the trees. Comparing the interception model to measurements of photosynthetically active radiation (PAR) underneath a tree, the qualitative agreement was high and the quantitative analysis showed a reasonable, albeit noisy, correspondence between the model output and the real world measurements. When comparing the estimations produced by the solar-geometry model and the tree volume (estimated also with LiDAR), a correspondence between the surface area of the tree and the interception was found. When comparing tree volume and light interception against actual yield numbers (total weight, average fruit weight and fruit count per tree), the observable trend was that light interception did better in predicting the average fruit size, while the volume did a better job of estimating the two others. The results were encouraging, however, because ground truth data were only available for 18 trees, future work will have to compare with a greater number of measurements over multiple growing seasons.

The Appalachian Region is a rich and diverse forest ecosystem impacted by present and past mining activities. The Surface Mining Control and Reclamation Act (SMCRA) of 1977 was enacted to resolve many of the environmental problems caused by surfacing mining, such as landslides, erosion, flooding, and poor water quality. As with many solutions, this one came with its own set of environmental problems due to compaction and the introduction of aggressive non-native grasses and shrubs altering hydrologic processes and ecosystem function. The Forestry Reclamation Approach (FRA) is a method for re-establishing forested ecosystems on mined lands. This project evaluated the effect of FRA on throughfall by comparing 10-, 20-, and 100-year old tree plots consisting of coniferous or deciduous trees. Throughfall rates were significantly impacted by tree type and age. Coniferous trees intercepted more rainfall than deciduous ones and the older trees tended to intercept the least. Presence/absence of leaves impacted throughfall depths for deciduous trees. Throughfall was significantly impacted by storm event characteristics. Results may help guide management of forested watersheds regarding strategies to reduce water yields on mined lands.

Two experimental rainfall simulation plots in the Edwards Aquifer region of Texas were established to measure the effects of brush clearing on surface and subsurface water movement pathways. Multi-stage rainfall simulations were carried out at a site with Juniperus ashei (ashe juniper) cover both before and after brush removal, with three replications of a particular rainfall event for each vegetation condition. Similar simulations were carried out on a plot with a longstanding grass cover. Both plots included trenches at their downhill ends for observation of shallow lateral subsurface flow. Canopy interception was found to represent a major water loss, with interception of 32.7 mm for an average 166 mm, 5.25 hr rainfall event. Brush clearing had little impact on surface runoff, with no overland flow occurring at the juniper plot for either vegetation condition, while 31.9 percent of applied rainfall moved as overland flow at the grass plot. This difference was attributed to differences in the structure and permeability of the epikarst. Brush removal caused significant (90 percent confidence level) reduction in shallow lateral subsurface flow into the trench after brush removal, with 56.7 percent of water reaching the surface entering the trench for the pre-cut condition and only 43.4 percent for the post-cut condition. However, subsurface water movement through other pathways increased from 31.0 to 54.1 percent after brush removal. This additional water, due to removal of canopy interception, could either move off-site through conduit and fracture flow or remain on site as storage in conduits, unconsolidated caliche/marl layers, or in soil pockets. Two tracer tests with fluorescent dyes were also conducted using simulated rainfall to assess discrete flow paths discharging into the trench at the downhill end of the juniper plot. Analysis of samples from sixteen outlet locations revealed that not all areas of the plot were connected hydraulically to the trench. Additionally, subsurface flow paths were found to have a high degree of interconnection, linking conduit flow outlets with multiple inlet locations on the plot surface. Conduits showed strong connection with an area surrounding juniper vegetation, with rapid water flow (up to 2.4 m/h) from this area.

Intercepter une cible en mouvement est un défi spatiotemporel relevé par de nombreuses espèces animales. Ici, nous nous sommes intéressés à la capture fovéale lors de l’orientation saccadique du regard vers une cible visuelle mobile chez le singe vigile. La théorie actuelle propose que l’interception saccadique fasse intervenir deux voies neuronales. Une première voie acheminerait, via le colliculus supérieur profond (CSp), un signal de position échantillonnée au générateur saccadique. La seconde, via le cervelet, fournirait une commande supplémentaire sur la base des signaux de mouvement visuel. Une étude comportementale a été réalisée afin d’analyser la dynamique de l’influence de ces signaux sur la trajectoire saccadique et a permis de mettre en évidence une influence continue. Dans une seconde étude, nous avons testé la robustesse du système oculomoteur à une perturbation spatiotemporelle inattendue (par microstimulation électrique du CSp) et montré la présence de saccades de correction précises. L’ensemble de nos résultats plaide pour une représentation continue du but des saccades d’interception. / Intercepting a visual moving target is a spatiotemporal challenge for the brain achieved by various species. Here, we investigated the foveal capture of a moving target by saccadic gaze shifts in the awake monkey. The current theory proposes that the saccadic interception involves two neural pathways. A first pathway would convey to the saccade burst generator a sampled target position signal through the superior colliculus (SC). The second one, through the cerebellum, would convey an additional command on the basis of motion-related signals. A behavioral experiment was performed to analyze the influence of motion-related signals on the saccade dynamics and allowed showing a continuous influence. In a second study, we tested the robustness of the oculomotor system to an unexpected spatiotemporal perturbation (by electrical microstimulation in the deep SC) and showed the presence of accurate correction saccades. Our results argue for a continuous representation of the saccade goal.

La compréhension du cycle de l'eau d'une région où les ressources en eau sont limitées est fondamentale pour assurer une gestion durable de celles-ci, c'est le cas de Galápagos. Cette thèse présente la première étude intégrée du fonctionnement hydrogéologique des aquifères perché de l'île San Cristóbal. Pour ce faire, une approche pluridisciplinaire, fondée sur la mise en place d'un site expérimental sur le bassin versant de Cerro Gato (CG), a été conduite. Pour quantifier les entrées d'eau dans le système hydrologique une approche canopée-transfert hydrique du sol a été utilise. La recharge est principalement affectée par l'altitude en raison de l'effet orographique sur les gradients de pluie et d'évapotranspiration. Néanmoins, à haute altitude, la différence est principalement associée à la couverture végétale en raison de l'apport additionnel fourni par l'interception du brouillard sous la forêt. Une analyse hydrologique montre que les pertes des bassins versants situés à haute-altitude deviennent les entrées d'eau souterraine des bassins versants situés à moyenne altitude (comme CG). Les données du méthode électromagnétique héliportée SkyTEM permettent définir l'extension du bassin hydrogéologique de CG qui est plus grande que le bassin hydrologique. Des approches précédemment décrites, découlent un modèle conceptuel des sources de CG. Ainsi, les eaux souterraines de ces sources sont issues d'un aquifère perché qui s'est formé à la faveur d'une fine couche peu perméable. Ce modèle est testé par simulations numériques qui montrent cette plausibilité. Cette thèse fournit les fondements scientifiques d'une gestion durable des ressources en eau. / The understanding of the hydrogeological functioning in regions such as San Cristobal Island (Galapagos), where water is limited, is fundamental for a suitable management of its resources. This work is the first study of this type on high-level aquifers in San Cristobal using a multi-disciplinary approach, based in the implementation of an experimental site and modeling strategies. For this purpose, a hydrological network was installed in Cerro Gato (CG) and surrounding watersheds. Inputs to the watershed are estimated using the joint modeling of a canopy and soil water transfer. Recharge rates are mainly affected by altitude in mid-elevation watersheds, whereas land cover is the main controlling factor at high-elevation watersheds because of the additional input of fog interception in forests. A hydrological analysis shows that losses from the high-elevation basins become groundwater inputs in the mid-elevation basins, while others have inputs from watersheds at the same altitude, such as CG. The detailed geometry of its hydrogeological watershed is obtained from the dataset of a high resolution AEM SkyTEM survey, which confirms the assumption that its hydrogeological watershed is bigger than its hydrological one. Results from these approaches allow proposing a hydrogeological conceptual model for the springs of CG, where the groundwater flow of springs is fed by a perched aquifer suspended by a low permeability thin layer. This model is tested with numerical simulations, which confirm the plausibility of the existence of a perched aquifer. This thesis provides scientific basis for an effective water management strategy.

As comunicações entre pessoas presentes são tuteladas na Constituição brasileira, como decorrência da liberdade de manifestação do pensamento, do direito à intimidade e à vida privada, da inviolabilidade do domicílio e do direito a não autoincriminação. Embora sejam constitucionalmente tuteladas, as comunicações entre pessoas presentes podem ser restringidas, desde que sejam observadas as exigências de reserva de lei, de reserva de jurisdição e de proporcionalidade. A interceptação de comunicação entre pessoas presentes é meio de investigação de prova, que, por meio de restrição a direitos e garantias fundamentais, visa a descoberta de fontes de prova para a persecução penal. Trata-se de instrumento processual que consiste em atividade de captação e de registro de comunicação entre pessoas presentes de caráter reservado, por um terceiro, com o emprego de meios técnicos, utilizados em operação oculta e simultânea à comunicação, sem o conhecimento dos interlocutores ou com o conhecimento de um ou de alguns deles. A interceptação domiciliar e a interceptação ambiental são espécies de interceptação de comunicação entre pessoas presentes. O objeto e o caráter insidioso desta modalidade de interceptação impõem a necessidade de uma disciplina jurídica autônoma, sob enfoques da admissibilidade e do procedimento probatório, que devem ser previstos em lei precisa e clara. / The communications between present people are protected by the Brazilian Constitution, arising out of the freedom of expression of ones thoughts, the right to intimacy and privacy, the dwelling defense and by the right not to produce self-incrimination. Despite being protected constitutionally, the communications between present people can be restricted as long as in accordance with the demands in reserve of law, in reserve of jurisdiction and of proportionality. The communications interception between present people is a means of investigation of evidence, which by means of restriction of rights and fundamental guarantees, objectives uncovering the sources of evidence for accusatory procedure. It is a question of procedural tool which consists in the activity of registering and recording communications between present people with secretive nature, by a third person, with the use of technical means, applied in concealed action and concurrent to the communication without the knowledge of the interlocutors or just the knowledge of one or few of them. Dwelling - interception and surrounding-interception are types of interception of communications between present people. The object and deceitful nature of this modality of interception imposes the need of an autonomous juridical regulation, under the perspectives of admissibility and of probatory procedure, which must be foreseen by clear and precise law

As comunicações entre pessoas presentes são tuteladas na Constituição brasileira, como decorrência da liberdade de manifestação do pensamento, do direito à intimidade e à vida privada, da inviolabilidade do domicílio e do direito a não autoincriminação. Embora sejam constitucionalmente tuteladas, as comunicações entre pessoas presentes podem ser restringidas, desde que sejam observadas as exigências de reserva de lei, de reserva de jurisdição e de proporcionalidade. A interceptação de comunicação entre pessoas presentes é meio de investigação de prova, que, por meio de restrição a direitos e garantias fundamentais, visa a descoberta de fontes de prova para a persecução penal. Trata-se de instrumento processual que consiste em atividade de captação e de registro de comunicação entre pessoas presentes de caráter reservado, por um terceiro, com o emprego de meios técnicos, utilizados em operação oculta e simultânea à comunicação, sem o conhecimento dos interlocutores ou com o conhecimento de um ou de alguns deles. A interceptação domiciliar e a interceptação ambiental são espécies de interceptação de comunicação entre pessoas presentes. O objeto e o caráter insidioso desta modalidade de interceptação impõem a necessidade de uma disciplina jurídica autônoma, sob enfoques da admissibilidade e do procedimento probatório, que devem ser previstos em lei precisa e clara. / The communications between present people are protected by the Brazilian Constitution, arising out of the freedom of expression of ones thoughts, the right to intimacy and privacy, the dwelling defense and by the right not to produce self-incrimination. Despite being protected constitutionally, the communications between present people can be restricted as long as in accordance with the demands in reserve of law, in reserve of jurisdiction and of proportionality. The communications interception between present people is a means of investigation of evidence, which by means of restriction of rights and fundamental guarantees, objectives uncovering the sources of evidence for accusatory procedure. It is a question of procedural tool which consists in the activity of registering and recording communications between present people with secretive nature, by a third person, with the use of technical means, applied in concealed action and concurrent to the communication without the knowledge of the interlocutors or just the knowledge of one or few of them. Dwelling - interception and surrounding-interception are types of interception of communications between present people. The object and deceitful nature of this modality of interception imposes the need of an autonomous juridical regulation, under the perspectives of admissibility and of probatory procedure, which must be foreseen by clear and precise law

<p>Voice over Internet Protocol (VoIP), also called IP telephony is rapidly becoming a familiar term and as a technology it is invading the enterprise, private usage, and educational and government organizations. Exploiting advanced voice coding & compression techniques and bandwidth sharing over packet switched networks, VoIP can dramatically improve bandwidth efficiency. Moreover enhanced security features, mobility support, and cost reduction features of VoIP are making it a popular choice for personal communication. Due to its rapid growth in popularity VoIP is rapidly becoming the next generation phone system.</p><p>Lawful interception is a mean of monitoring private communication of users that are suspected of criminal activities or to be a threat to national security. However, government regulatory bodies and law enforcement agencies are becoming conscious of the difficulty of lawful interception of public communication due to the mobilitysupport and advanced security features implemented in some implementations of VoIP technology. There has been continuous pressure from the government upon the operators and vendors to find a solution that would make lawful interception feasible and successful. Key escrow was proposed as a solution by the U. S. National Security Agency. In key escrow the key(s) for a session are entrusted to a trusted third party and upon proper authorization law enforcement agencies can receive the session key(s) from this trusted third party However, key escrow adds some security vulnerabilities and potential risks as an unethical employee of the key escrow agent (or a law enforcement agency that has received the session key(s)) can misuse the key(s) to forge content of a communication session -- as he or she possesses the same key(s) as the user used for this session.</p><p>This thesis addresses the issue of forged session content, by proposing, implementing, and evaluating a cryptographic model which allows key escrow session content. The implementation utilizes an existing implementation of a Session Initiation Protocol (SIP) user agent ‘minisip’ developed at KTH. The performance evaluation results suggest that the proposed model can support key escrow while protecting the user communication from being forged with the cost of minimal computational resource and negligible overhead. <em>without</em> the possibility of undetectable fabrication of<em><strong>  </strong></em>session content. The implementation utilizes an existing implementation of a Session Initiation Protocol (SIP) user agent ‘minisip’ developed at KTH. The performance evaluation results suggest that the proposed model can support key escrow while protecting the user communication from being forged with the cost of minimal computational resource and negligible overhead.</p>