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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.
211

Disaster Management in India: Analysis of Factors Impacting Capacity Building

Erramilli, Bala Prasad 09 December 2008 (has links)
Governments are responsible for administrative arrangements dealing with disasters. Effective policies play a vital role in mitigating the impact of disasters and reducing likely losses of life and property. Yet, it had been noted that such losses were increasing, raising questions about efficacy of government policies and the factors that made them effective. This study adopted a comparative method, responding to a long-standing demand of disaster research, for examining the record in India. There were noticeable differences among its states, with some having undertaken comprehensive reform in an all-hazards approach, while others continued with old policies. This research studied four states with the objective of identifying variables that were critical in undertaking policy reform for building capacities. The roles of economic resources, democratically decentralized institutions, political party systems and focusing events were examined. Findings revealed that these factors had varying impact on state capabilities. Economic resources were an inevitable part of disaster management, but did not necessarily translate into policy reform. Panchayati Raj Institutions, which were democratically decentralized bodies, displayed tremendous potential. However, their role was limited mostly to the response phase, with states severely circumscribing their involvement. The nature of political party systems was able to explain policy reform to an extent. Cohesive systems in Gujarat, Tamil Nadu and Orissa correlated with administrative capacities, unlike in fragmented Bihar. However, anti-incumbency sentiments and strong community mobilization impacted contestation more than electoral salience of public goods. The most nuanced and significant explanation was provided by experience of focusing events. States that suffered major disasters revealed unmistakable evidence of double-loop learning, leading to comprehensive policy reform and capacity building. This research provides empirical support to theory about the role of focusing events and organizational learning in policy reform. Methodologically, it underscores the importance of the comparative approach, and its successful application in a federal framework. The significance of this research is most for policy makers and practitioners, as it serves to alert them on the need for reform without waiting for the next big disaster to catch them unprepared.
212

Inversion of Nonlinear Dispersive Wave and its Application in Determining Tsunami Wave Soure

Li, Lieh-Yu 13 April 2011 (has links)
In this study, the method of deciding the water level of the initial tsunami is proposed by using spatial-temporal focusing (Coalescence) theory and waveform inversion reciprocal with Green function. Tsunami and earthquake are so closely bonded that the current tsunami numerical model is dependent on the parameters of the fault and the initial tsunami water level by calculating the theory of half flexibility. But in fact, it is not easy to have the parameters of seabed fault so that the initial tsunami water level is very hard to get a accurate value. On the other hand, although the parameters of fault can be speculated by seismic waves, because ground is uneven medium, therefore, it is still a lot of improvement to get the parameters of fault by using seismic waves. For the tsunami simulation, if you have the value of the initial tsunami water level, the fault parameters can be estimated.Since the propagation of tsunami in the ocean is a linear behavior, the propagating process is affected by the topography of the ocean and the nonlinear effect so minimal that it is to satisfy the linear shallow water equations and the requirement of reversibility;However, in fact, the values of the water level measured by the tide stations on the coast are influenced by the shoaling effect so that the reversibility of linear system can not be directly applied to Coastal areas.Therefore, the overall Inversion procedure on this study consists of two parts; the first one is that the usage of variable coefficient Korteweg-de Vries (vKdV) equation and the Coalescence theory inverses the data gathered by the Coastal tide stations to the water level data where the depth is more than 50m on the linear region, and compares the above results with the stimulation and confirms the accuracy of the inversed waveform;The second one is that according to the reversibility of the linear system the use of least squares and least squares QR- decomposition (LSQR) method reproduce the initial tsunami wave source that compares with the initial tsunami wave source by stimulating and has a very good conformity. The seismic parameters can be easily decided by the above results.
213

MATERIALS, METHODS, AND INSTRUMENTATION FOR PREPARATIVE-SCALE ISOELECTRIC TRAPPING SEPARATIONS

North, Robert Yates 2009 May 1900 (has links)
Isoelectric trapping (IET) has become an accepted preparative-scale electrophoretic separation technique. However, there are still a number of shortcomings that limit its utility. The performance of the current preparative-scale IET systems is limited by the serial arrangement of the separation compartments, the difficulties in the selection of the appropriate buffering membranes, the effect of Joule heating that may alter separation selectivity and a lack of methods for the determination of the true, operational pH value inside the buffering membranes. In order to bolster the current membrane pH determination methods which rely on the separation of complex ampholytic mixtures, a fluorescent carrier ampholyte mixture was synthesized. The use of a fluorescent mixture allows for a reduced load of carrier ampholytes, thereby reducing a possible source of error in the pH determinations. A mixture of carrier ampholytes tagged with an alkoxypyrenetrisulfonate fluorophore was shown to have suitable fluorescence and ampholytic properties and used to accurately determine the pH of high pH buffering membranes under actual IET conditions. In a more elegant solution to the difficulties associated with pH determinations, a method utilizing commercial UV-transparent carrier ampholytes as the ampholyte mixture to be separated was developed. By using commercial carrier ampholytes and eliminating the need to synthesize, purify, and blend fluorescently tagged ampholytes, the new method greatly simplified the determination of the operational pH value of the buffering membranes. In order to address the remaining limitations, a new system has been developed that relies on (i) parallel arrangement of the electrodes and the collection compartments, (ii) a directionally-controlled convection system for the delivery of analytes, (iii) short anode-to-cathode distances, (iv) short intermembrane distances, and (v) an external cooling system. This system has been tested in four operational modes and used for the separation of small molecule ampholytic mixtures, for the separation of protein isoforms, and direct purification of a target pI marker from a crude reaction mixture.
214

Spin-polarized transport in magnetic nanostructures

O'Gorman, Brian Curtin 19 January 2011 (has links)
Two of the principal phenomena observed and exploited in the field of spintronics are giant magnetoresistance (GMR) and spin transfer torque (STT). With GMR, the resistance of a magnetic multilayer is affected by the relative orientation of its magnetic layers due to (electron) spin dependent scattering. For the STT effect, a spin-polarized electric current is used to alter the magnetic state of a ferromagnet. Together, GMR and STT are at the foundation of numerous technologies, and they hold promise for many more applications. To achieve the high current densities (~10¹² A/m²) that are necessary to observe STT effects, point contacts – constricted electrical pathways (~1–100 nm in diameter) between conducting materials – are often used because of their small cross-sectional areas. In this sense, we have explored STT in bilayer magnetic nanopillars, where an electric current was used to induce precession of a ferromagnetic layer. This precessional state was detected as an increase in resistance of the device, akin to GMR. Temperature dependent measurements of the onset of precession shed light on the activation mechanism, but raised further questions about its detailed theory. Point contacts can also be used as local sources or detectors of electrons. In this context, we have observed transverse electron focusing (TEF) in a single crystal of bismuth. TEF is a k-selective technique for studying electron scattering from within materials. Using lithographically fabricated point contacts, we have studied the temperature dependence of the relaxation time for ballistic electrons from 4.2 to 100 K. These measurements indicated a transition between electron-electron dominated scattering at low temperatures and electron-phonon scattering as the Debye temperature was approached. We present preliminary work toward a TEF experiment to measure spin dependent scattering from a non-magnet/magnet interface. We also investigated spin wave propagation in thin, magnetic waveguide structures. At the boundary between the waveguide and continuous magnetic film, spin wave rays were found to radiate into the film, or to reflect and form standing waves in the waveguide. A circular defect in the waveguide was observed to cause diffraction of spin waves, generating an interference pattern of higher modes of oscillation. / text
215

Techniques de déduction automatique vues comme recherche de preuve en calcul des séquents

Farooque, Mahfuza 19 December 2013 (has links) (PDF)
Le raisonnement assisté par ordinateur joue un rôle crucial en informatique et en logique mathématique, de la programmation logique à la déduction automatique, en passant par les assistants à la démonstration. Le but de cette thèse est la conception d'un cadre général où différentes techniques de raisonnement assisté par ordinateur peuvent être implémentées, pour que ces dernières puissent collaborer, être généralisées, et être implémentées de manière plus sûre. Le cadre que je propose est un calcul des séquents appelé LKp(T), qui généralise un système de la littérature à la présence d'une théorie pour laquelle nous avons une procédure de décision, comme l'arithmétique linéaire. Cette thèse développe la méta-théorie de LKp(T), avec par exemple la propriété de complétude logique. Nous montrons ensuite comment le système spécifie une procédure de recherche de preuve qui émule une technique connue du domaine de la Satisfiabilité-modulo-théories appelée DPLL(T). Enfin, les tableaux de clauses et les tableaux de connexions sont d'autres techniques populaires en déduction automatique, d'une nature relativement différente de DPLL. Cette thèse décrit donc également comment ces techniques de tableaux peuvent être décrites en termes de recherche de preuve dans LKp(T). La simulation est donnée à la fois pour la logique propositionnelle et la logique du premier ordre, ce qui ouvre de nouvelles perspectives de généralisation et de collaboration entre les techniques de tableaux et DPLL, même en présence d'une théorie.
216

Kampinės dispersijos panaudojimas galingų ir ultratrumpų impulsinių šviesos pluoštų formavimui netiesinių sąveikų metu / The use of angular dispersion for formation of high peak power and ultrashort pulsed light beams in nonlinear interactions

Zaukevičius, Audrius 27 December 2012 (has links)
Disertacija yra skirta išnagrinėti ir paaiškinti impulsinių šviesos pluoštų parametrinio stiprinimo metu vykstančius reiškinius. Ypatingas dėmesys yra skiriamas erdvinei-laikinei impulsinio šviesos pluošto dinamikai stiprinimo metu. Visi nagrinėjamų reiškinių tyrimai buvo atliekami taikant skaitmeninio modeliavimo metodus. Modelyje panaudotos lygtys buvo išvestos iš Maksvelo lygčių, išsamiai aptariant lygčių išvedimo metu daromas prielaidas. Naudojantis pateiktu modeliu buvo gauti skaitmeniniai rezultatai, kurie parodė, jog nekolineariame parametriniame stiprintuve, kuomet kaupinimo ir signalinio impulsų frontai nėra sutapatinti, signalinis impulsas tampa pakrypęs ir be kampinės dispersijos taip pat įgyja ir erdvinį čirpą. Nustatyta, kad indukuotų erdvinės ir kampinės dispersijų mažėjimo sparta, didinant signalinio impulso laikinį čirpą, yra skirtinga. Pagrindiniai šio teorinio tyrimo rezultatai buvo patvirtinti eksperimentiškai. Taip pat šioje disertacijoje yra pristatomas naujas ir universalus impulsinių kūginių bangų parametrinio stiprinimo metodas, kuriame sustiprinti impulsai patys susispaudžia laike ir erdvėje paprasčiausiai sklisdami laisvoje erdvėje. Šis metodas leidžia formuoti didelio smailinio intensyvumo invariantiškus bangų paketus, galinčius nusklisti daugelį Relėjaus nuotolių norimoje medžiagoje. Priešingai nei įprastame čirpuotų impulsų stiprinimo metode, šis metodas nereikalauja impulsų spaustuvo, o tai žymiai palengvina parametrinį kelių optinių ciklų... [toliau žr. visą tekstą] / This thesis is aimed to provide an extensive picture of the phenomena encountered in optical parametric amplification of pulsed light beams. The particular attention is paid for the spatio-temporal dynamics of the pulsed light beams being amplified. All the research has been done by means of numerical methods. The equations used in the model were derived from the Maxwell’s equations and the assumptions made along the derivation of equations were discussed. Using the presented model it has been numerically demonstrated, that in noncollinear optical parametric amplifier, when pulse fronts of pump and signal are not matched, the signal pulse becomes tilted and aside from angular dispersion acquires a spatial chirp. It has been shown, that the magnitudes of the induced spatial and angular dispersions decrease at different rates with the increase of the signal pulse temporal chirp. The main results of this study were verified experimentally. Additionally, in this thesis we have proposed a novel and versatile method for pulsed conical wave parametric amplification with subsequent spatio-temporal compression during propagation in free space. It allows to form ultra-intense and propagation invariant wave-packets capable to propagate over many Rayleigh range in the desired material. In contrast to ordinary chirped-pulse amplification technique it does not require a pulse compressor, thus greatly facilitates the parametric amplification of few-cycle light pulses.
217

The use of angular dispersion for formation of high peak power and ultrashort pulsed light beams in nonlinear interactions / Kampinės dispersijos panaudojimas galingų ir ultratrumpų impulsinių šviesos pluoštų formavimui netiesinių sąveikų metu

Zaukevičius, Audrius 27 December 2012 (has links)
This thesis is aimed to provide an extensive picture of the phenomena encountered in optical parametric amplification of pulsed light beams. The particular attention is paid for the spatio-temporal dynamics of the pulsed light beams being amplified. All the research has been done by means of numerical methods. The equations used in the model were derived from the Maxwell’s equations and the assumptions made along the derivation of equations were discussed. Using the presented model it has been numerically demonstrated, that in noncollinear optical parametric amplifier, when pulse fronts of pump and signal are not matched, the signal pulse becomes tilted and aside from angular dispersion acquires a spatial chirp. It has been shown, that the magnitudes of the induced spatial and angular dispersions decrease at different rates with the increase of the signal pulse temporal chirp. The main results of this study were verified experimentally. Additionally, in this thesis we have proposed a novel and versatile method for pulsed conical wave parametric amplification with subsequent spatio-temporal compression during propagation in free space. It allows to form ultra-intense and propagation invariant wave-packets capable to propagate over many Rayleigh range in the desired material. In contrast to ordinary chirped-pulse amplification technique it does not require a pulse compressor, thus greatly facilitates the parametric amplification of few-cycle light pulses. / Disertacija yra skirta išnagrinėti ir paaiškinti impulsinių šviesos pluoštų parametrinio stiprinimo metu vykstančius reiškinius. Ypatingas dėmesys yra skiriamas erdvinei-laikinei impulsinio šviesos pluošto dinamikai stiprinimo metu. Visi nagrinėjamų reiškinių tyrimai buvo atliekami taikant skaitmeninio modeliavimo metodus. Modelyje panaudotos lygtys buvo išvestos iš Maksvelo lygčių, išsamiai aptariant lygčių išvedimo metu daromas prielaidas. Naudojantis pateiktu modeliu buvo gauti skaitmeniniai rezultatai, kurie parodė, jog nekolineariame parametriniame stiprintuve, kuomet kaupinimo ir signalinio impulsų frontai nėra sutapatinti, signalinis impulsas tampa pakrypęs ir be kampinės dispersijos taip pat įgyja ir erdvinį čirpą. Nustatyta, kad indukuotų erdvinės ir kampinės dispersijų mažėjimo sparta, didinant signalinio impulso laikinį čirpą, yra skirtinga. Pagrindiniai šio teorinio tyrimo rezultatai buvo patvirtinti eksperimentiškai. Taip pat šioje disertacijoje yra pristatomas naujas ir universalus impulsinių kūginių bangų parametrinio stiprinimo metodas, kuriame sustiprinti impulsai patys susispaudžia laike ir erdvėje paprasčiausiai sklisdami laisvoje erdvėje. Šis metodas leidžia formuoti didelio smailinio intensyvumo invariantiškus bangų paketus, galinčius nusklisti daugelį Relėjaus nuotolių norimoje medžiagoje. Priešingai nei įprastame čirpuotų impulsų stiprinimo metode, šis metodas nereikalauja impulsų spaustuvo, o tai žymiai palengvina parametrinį kelių optinių ciklų... [toliau žr. visą tekstą]
218

霾害之後 ——以北京PM2.5監測資料公開探討政策轉向之過程 / After Haze: the Policy Change Process of PM2.5 Information Disclosure

湯思斯, Tang, Si Si Unknown Date (has links)
2011年末,一場持續數天的霧霾天氣席捲北京,環保部門卻並未提供相關污染物PM2.5的監測數據。相關法律法規的落後,以及環保部門的不作為,激起民眾的不滿。隨著美國駐華大使館、環保NGO、微博名人和廣大民眾的持續參與與推動,政府相關資訊政策也逐漸變化,最終將PM2.5納入空氣質量標準并公佈監測數據。本文以此次霧霾污染事件作為「焦點事件」切入點,首先藉由事件回顧討論“誰來監測”的問題,探討了環境信息公開的理論與實踐;然後分析政策變化的過程,歸納「政策變化模型」,討論政策變化形成的原因,分析各行為者在政策變化中的角色和作用;最後,由此事件得出這一政策轉變的影響以及啟示,歸納目前環境資訊公開領域制度層面所存在的缺失,并就此事件的經驗對於政府和環境NGO給出建議。 / In the end of 2011, the city of Beijing was hit by a long-lasting haze. However, the city’s Environmental Protection Bureau was unable to provide the public with the data of a critical pollutant – PM2.5. The political inaction of the government has caused great discontent among the public. With the continuous efforts from the US Embassy in China, environmental NGOs, Sina Weibo celebrity users and the public, the official information disclosure policy has seen a big change – the government has adopted a higher standard and taken steps to publish the data of PM2.5. This article takes the haze incident as a “focusing event”. It firstly reviews the case and discusses the theories and practices of the environmental information disclosure. It then analyzes the process of this policy change and forms a policy change model to determine the contributing factors and the roles of different actors. The concluding part summarizes the omission of the current information disclosure system, and makes recommendations to the government and the NGOs.
219

付箋紙を用いたフォーカシングの空間づくり

Ito, Yoshimi, 伊藤, 義美 25 October 2001 (has links)
No description available.
220

フォーカシング体験とパーソナリティの研究

伊藤, 義美, Ito, Yoshimi, 小畑, 豊美, Obata, Atsumi, 栗野, 理恵子, Kurino, Rieko 25 March 2002 (has links)
No description available.

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