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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Full spectrum : Amnesty International and economic, social, and cultural rights

Rowe, Paul W. 04 June 2009
In 2001, Amnesty International, the worlds largest international human rights non-governmental organization, made the decision to change its narrow mandate into a much broader mission statement that called for the protection and promotion of both civil and political rights and economic, social and cultural rights. Although the organization had added to its original mandate core concerning the release of prisoners of conscience before, the addition of economic, social, and cultural rights represented a major shift away from Amnesty Internationals classic focus on civil and political rights. Amnesty Internationals decision to promote all of the human rights listed in the United Nations Universal Declaration of Human Rights and become a full spectrum human rights defender was a controversial one within the organization. The debate by the Amnesty membership over whether to accept an expanded form of mandate took place within the organization over a period of a decade before any changes were made. Concerns and fears over accepting economic, social and cultural rights into the mandate ranged from the practical to the theoretical.<p> This thesis will look at the decision made by Amnesty International to begin actively promoting and defending economic, social and cultural rights. It will examine why a leading human rights organization decided to modify its focus considerably and what the challenges were in doing this. In exploring the issues of contention brought up during the debates by the organizations membership, the larger questions surrounding international political acceptance of economic, social, and cultural rights will be examined.
82

Lågoffsetkomparator / Lowoffsetcomparator

Fransson, Daniel January 2002 (has links)
Detecting small signals with a comparator demands that the total voltage offset is lower than the actual signal. The total offset includes the voltage offset in the comparator and the voltage offset that is created by the offset currents that flows thru the load at the comparators input. The goal with this comparator that has been developed has been that it will have a total voltage offset at maximum 500 uV. The comparator does not need to be extremely fast or does not need to operate in a big frequency area. To have all the flexibility that is needed a full custom technique is used. When the mismatch is most unfavourable the total offset is 209.24 uV which is within the goal. / För att kunna detektera små signalnivåer med en komparator krävs att den har en lägre total spänningsoffset än den signalnivå den skall detektera. I den totala offseten ingår dels den rena spänningsoffseten i komparatorn och dels den spänningsoffset som kommer att skapas när offsetströmmar på komparatorns ingångar går igenom den last som finns på ingången. Målet med den komparator som utvecklats har varit att den skall ha en total spänningsoffset på maximalt 500 uV. Inga direkta krav såsom att den skall vara snabb och att den skall kunna arbeta inom ett stort frekvensområde finns. För att få den flexibilitet som behövs är komparatorn konstruerad i en så kallad full custom teknik. När missanpassningen är som mest ogynnsam hamnar den totala spänningsoffseten på 209.24 uV vilket ligger inom målet med god marginal.
83

L'estudi de les funcions utilitzant el full de càlcul com a eina de treball: anàlisi d'un procés constructiu basat en la manipulació i la visualització

Segura Lores, Maria Josefa 02 October 2001 (has links)
Analitzem el procés d'aprenentatge de l'alumnat d'ensenyament secundària en relació a l'estudi de funcions amb la utilització del full de càlcul com a eina de treball sota un model metodològic constructiu enfocat en la manipulació la visualització.Com a treball d'innovació pretenem dissenyar i construir una seqüència d'aprenentatge sobre les funcions i implementar la unitat didàctica elaborada. Com a recerca, en primer lloc, analitzar el procés d'aprenentatge dels alumnes en relació als continguts treballats en el tema de funcions, l'eina informàtica (full de càlcul), la metodologia emprada, la unitat didàctica elaborada i l'actitud de l'alumnat. I en segon lloc, millorar la unitat didàctica elaborada i que constitueix part del currículum de l'aprenentatge.Aquests quatre objectius es concreten en:a) Revisar, en procés constructiu, la unitat didàctica dissenyada i elaborar una nova proposta, partint de l'anàlisi i la classificació de les dificultats i/o els errors comesos pels alumnes en relació a l'estudi de les funcions i en l'ús del full de càlcul per estudiar-les i , en concret atenent a les seves característiques, intentant determinar els motius que els provoquen.b) Valorar com influencia, en el procés d'aprenentatge de l'alumnat, el full de càlcul.c) Revisar la metodologia de treball desenvolupada en la innovació didàctica en l'estudi de funcions utilitzant el full de càlcul sota un procés constructiu enfocat en la manipulació i la visualització.d) Concretar les actituds de l'alumnat dintre del seu procés d'aprenentatge. / This thesis belongs to the field of Mathematical Didactics (education, learning). We analyse the learning process of the secondary education student in relation to the study of functions with the use of spreadsheets as a work tool with a constructive methodologist model directed to manipulation and visualization.There are two focuses: as an innovation work and as a research work.As an innovation work we design and construct a learning sequence about functions and we create a teaching unit. Therefore, first of all we have prepared a teaching unit thought to study the functions using the spreadsheets at 4th level of obligatory secondary education (ESO in Spanish abbreviation). The students are 15 years old. The study of the functions goes towards the identification of the graphic behaviour of a straight line and a parabola according to the variations of its parameters and to recognize its characteristics across different algebraic situations that have been generated by affine and quadratic function. Secondly, we prepared a new teaching unit thought for Humanities "Bachillerato" (Spanish high school). The students are 16 to 18 years old. The purpose is to find and to recognize the functions, the graphics and the characteristics of the functions from the algebraic expression of the function. The functions studied are exponential, logarithmic, polynomial and rational functions. In the two last functions are applied derivates.As a research, firstly, we have analysed the student learning process in relation to the contents worked on the function subject, computer tool (spreadsheets), methodology used, the teaching unit and the student's attitude. Secondly, we have improved the teaching unit that constitutes a part of the learning curriculum.We have concreted these objectives in: a) to revise, in constructive process, the designed teaching unit and to elaborate a new proposal, b) to value how the spreadsheets affects the student's learning process, c) to revise the work methodology developed in the didactic innovation in the study of the functions using the spreadsheets for manipulation and visualization, d) to concrete the student's attitude within their learning process.Taking into account the objectives above mentioned the stages of our research design are: stage of elaboration, empiric stage and conclusive stage. The first is the stage of elaboration of the teaching unit; the second is the empiric stage, and finally, the conclusive stage where, at the end of every school year at every studied level, we analyse all the information collected during the process development and finally, we draw the conclusions.
84

Optimal Routing and Power Allocation for Wireless Networks with Imperfect Full-Duplex Nodes

Ramirez Dominguez, David 24 July 2013 (has links)
We study a wireless full-duplex network with imperfect interference cancellation and solve the routing and power allocation problem in this network. We use a model that focuses on the effects of full-duplex by including residual self-interference and one hop interference while other interfering signals are considered negligible in comparison. We first solve the optimal power allocation for a fixed route. We then propose a priority-first search algorithm to find the joint route and power allocation to maximize throughput. The algorithm proposed has a non decomposable priority metric, but is efficiently evaluated by our solution for a fixed route. We analyze the performance of our solution in a more realistic model by deriving bounds between optimal solutions in both models. Through simulations we show that, even with imperfect interference cancellation, full-duplex achieves a higher throughput than half-duplex or direct transmission for moderate transmission power.
85

Full-Duplex Infrastructure Nodes: Achieving Long Range with Half-duplex Mobiles

Everett, Evan 06 September 2012 (has links)
One of the primary sources of inefficiency in today's wireless networks is the half-duplex constraint - the assumption that nodes cannot transmit and receive simultaneously in the same band. The reason for this constraint and the hurdle to full-duplex operation is self-interference: a node's transmit signal appears at its own receiver with very high power, desensitizing the receiver electronics and precluding the reception of a packet from a distant node. Recent research has demonstrated that full-duplex can indeed be feasible by employing a combination of analog and digital self-interference cancellation mechanisms. However, two glaring limitations remain. The first is that the full-duplex state-of-the-art requires at least two antennas and extra RF resources that space-constrained mobile devices may not be able to accommodate. The second limitation is range: current full-duplex demonstrations have been for ranges less than 10~m. At longer distances nodes must transmit with higher power to overcome path loss, and the power differential between the self-interference and the signal-of-interest becomes more that the current cancellation mechanisms can handle. We therefore present engineering solutions for answering the following driving questions: (a) can we leverage full-duplex in a network consisting mostly of half-duplex mobiles? and (b) can we extend the range of full-duplex by achieving self-interference suppression sufficient for full-duplex to outperform half-duplex at ranges exceeding 100 m? In answer to the first question, we propose moving the burden of full-duplexing solely to access points (APs), enabling the AP to boost network throughput by receiving an uplink signal from one half-duplex mobile, while simultaneously transmitting a downlink signal to another half-duplex mobile in the same band. In answer to the second question we propose an AP antenna architecture that uses a careful combination of three mechanisms for passive suppression of self-interference: directional isolation, absorptive shielding, and cross-polarization. Results from a 20 MHz OFDM prototype demonstrate that the proposed AP architecture can achieve 90+ dB total self-interference suppression, enabling >50% uplink rate gains over half-duplex for ranges up to 150 m.
86

Full-duplex Wireless: Design, Implementation and Characterization

January 2012 (has links)
One of the fundamental assumptions made in the design of wireless networks is that the wireless devices have to be half-duplex, i.e., they cannot simultaneously transmit and receive in the same frequency band. The key deterrent in implementing a full-duplex wireless device, which can simultaneously transmit and receive in the same frequency band, is the large power differential between the self-interference from a device's own transmissions and the signal of interest coming from a distant source. In this thesis, we revisit this basic assumption and propose a full-duplex radio design. The design suppresses the self-interference signal by employing a combination of passive suppression, and active analog and digital cancellation mechanisms. The active cancellations are designed for wideband, multiple subcarrier (OFDM), and multiple antenna (MIMO) wireless communications systems. We then implement our design as a 20 MHz MIMO OFDM system with a 2.4 GHz center frequency, suitable for Wi-Fi systems. We perform extensive over-the-air tests to characterize our implementation. Our main contributions are the following: (a) the average amount of active cancellation increases as the received self-interference power increases and as a result, the rate of a full-duplex link increases as the transmit power of communicating devices increases, (b) applying digital cancellation after analog cancellation can sometimes increase the self-interference and the effectiveness of digital cancellation in a full-duplex system will depend on the performance of the cancellation stages that precede it, (c) our full-duplex device design achieves an average of 85 dB of self-interference cancellation over a 20 MHz bandwidth at 2.4 GHz, which is the best cancellation performance reported to date, (d) our full-duplex device design achieves 30-84% higher ergodic rates than its half-duplex counterpart for received powers in the range of [-75, -60] dBm. As a result, our design is the first one to achieve Wi-Fi ranges; in comparison, no implementation to date has achieved Wi-Fi ranges. Consequently, we have conclusively demonstrated that Wi-Fi full-duplex is practically feasible and hence shown that one of the commonly made assumptions in wireless networks is not fundamental.
87

Distributed Full-duplex via Wireless Side Channels: Bounds and Protocols

Bai, Jingwen 16 September 2013 (has links)
In this thesis, we study a three-node full-duplex network, where the infrastructure node has simultaneous up- and downlink communication in the same frequency band with two half-duplex nodes. In addition to self-interference at the full-duplex infrastructure node, the three-node network has to contend with the inter-node interference between the two half-duplex nodes. The two forms of interferences differ in one important aspect that the self-interference is known at the interfered receiver. Therefore, we propose to leverage a wireless side-channel to manage the inter-node interference. We characterize the impact of inter-node interference on the network achievable rate region with and without a side-channel between the nodes. We present four distributed full-duplex inter-node interference cancellation schemes, which leverage the device-to-device wireless side-channel for improved interference cancellation. Of the four, bin-and-cancel is asymptotically optimal in high signal-to-noise ratio limit which uses Han-Kobayashi common-private message splitting and achieves within 1 bits/s/Hz of the capacity region for all values of channel parameters. The other three schemes are simpler compared to bin-and-cancel but achieve the near-optimal performance only in certain regimes of channel values. Asymptotic multiplexing gains of all proposed schemes are derived to show analytically that leveraging the side channel can be highly beneficial in increasing the multiplexing gain of the system exactly in those regimes where inter-node interference has the highest impact.
88

Halltider : Eskilstunas handboll- och innebandyföreningars tillgång till 40x20 planer

Petersson, Petrus January 2010 (has links)
For youths leisure activity the organized sport is vital. Young people become increasingly sedentary and the healths of young people are the various municipalities responsibility. In Eskilstuna, the handball is very popular but there are only three grounds that meet the standards of the dimensions of a handball pitch, 40x20 meters. The same dimensions are used by floorball. Eskilstuna municipality owns one of these, the other two is privately built and owned and the municipality rents time in the halls. IF Guif and HK Eskil are two handballclubs in the central part of Eskilstuna. They have access to only one 40x20 meters pitch that they have to share between their 45 teams. Hence forth the handball player’s in Eskilstuna rarely has the opportunity to practise at full-size pitches before they reach junior age. In the part of Eskilstuna called Torshälla, the situations for another handballclubb is much better. Gökstens BK uses the full-sized Ellfolkarenan together with Torshälla IBK, a floorballclub. The new built Ellfolkarenan has been a big boast for Gökstens BK and they are now pleased white their access to practice areas. Floorballclubs in Eskilstuna have, due to private construction, access to two full-sized halls. In addition, they are practising in halls which are just below the authorized dimensions. Despite this, they have difficulties to get access to the new hall times to expand their club by starting up new teams with practise at attractive times of the day. With only three full-sized halls, Eskilstuna is among the big-sized municipalities in Sweden with most people per full-sized hall. If a new multipurposearena with three pitches would be built in Eskilstuna, the municipality would count themselves by those of the big-seized municipalities that are below average of people per full-sized hall.
89

Simulating a Novel Nitrogen Removal Process Using EnviroPro Designer

Waheed, Jabeen 18 May 2010 (has links)
Ammonia removal is an important problem that Canadian municipalities are encountering in their wastewater treatment systems due to ammonia’s adverse environmental effects and its increasingly stringent discharge standards. Nitrogen compounds are generally removed from wastewater by a combination of nitrification and denitrification. In full nitrification, ammonia is first biologically oxidized to nitrite, which is then oxidized to nitrate by nitrite-oxidizing bacteria. In denitrification, the resulting nitrate has to be first reduced to nitrite in order to be converted to nitrous oxide, then nitric oxide, and finally to nitrogen gas. Since, nitrite is an intermediary compound in both nitrification and denitrification, it may be more efficient to produce a partial nitrification up to nitrite and then denitrification starting from this nitrite. In this research, EnviroPro Designer was used to simulate, optimize and compare process models for both full nitrification and partial nitrification. The Full System model simulates the traditional full nitrification followed by denitrification. Partial System-1 model simulates the partial nitrification process followed by denitrification directly from nitrite. Partial System-1 significantly reduced the ammonia and domestic waste concentrations in the effluent while achieving 1.5 times faster denitrification rates and utilizing 33% less oxygen. Partial System-1 was further optimized to develop a novel nitrogen removal process, Partial System-3, which incorporated an additional third anoxic stage while the aerobic stage in sludge treatment was removed. Partial System-3 successfully reduced the ammonia and nitrite concentrations in the effluent to values well within the current guidelines while consuming 50% less oxygen than the Full System, which reflected favorably on utility savings. It also showed 2 times faster denitrification rates, and displayed superior domestic waste consumption. Furthermore, the capital and operational costs were less than other nitrogen removal systems investigated in this thesis. The novel Partial System-3 appears to be the best option for removal of nitrogen from medium to high strength wastewater, and further experimental research is required to confirm the kinetic and yield constants assumed in the simulations.
90

Full spectrum : Amnesty International and economic, social, and cultural rights

Rowe, Paul W. 04 June 2009 (has links)
In 2001, Amnesty International, the worlds largest international human rights non-governmental organization, made the decision to change its narrow mandate into a much broader mission statement that called for the protection and promotion of both civil and political rights and economic, social and cultural rights. Although the organization had added to its original mandate core concerning the release of prisoners of conscience before, the addition of economic, social, and cultural rights represented a major shift away from Amnesty Internationals classic focus on civil and political rights. Amnesty Internationals decision to promote all of the human rights listed in the United Nations Universal Declaration of Human Rights and become a full spectrum human rights defender was a controversial one within the organization. The debate by the Amnesty membership over whether to accept an expanded form of mandate took place within the organization over a period of a decade before any changes were made. Concerns and fears over accepting economic, social and cultural rights into the mandate ranged from the practical to the theoretical.<p> This thesis will look at the decision made by Amnesty International to begin actively promoting and defending economic, social and cultural rights. It will examine why a leading human rights organization decided to modify its focus considerably and what the challenges were in doing this. In exploring the issues of contention brought up during the debates by the organizations membership, the larger questions surrounding international political acceptance of economic, social, and cultural rights will be examined.

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