Dissertations / Theses on the topic 'Limited space'

In this thesis, we present variants of Shor and Zhurbenko's r-algorithm, motivated by the memoryless and limited memory updates for differentiable quasi-Newton methods. This well known r-algorithm, which employs a space dilation strategy in the direction of the difference between two successive subgradients, is recognized as being one of the most effective procedures for solving nondifferentiable optimization problems. However, the method needs to store the space dilation matrix and update it at every iteration, resulting in a substantial computational burden for large-sized problems. To circumvent this difficulty, we first develop a memoryless update scheme. In the space transformation sense, the new update scheme can be viewed as a combination of space dilation and reduction operations. We prove convergence of this new algorithm, and demonstrate how it can be used in conjunction with a variable target value method that allows a practical, convergent implementation of the method. For performance comparisons we examine other memoryless and limited memory variants, and also prove a modification of a related algorithm due to Polyak that employs a projection on a pair of Kelley's cutting planes. These variants are tested along with Shor's r-algorithm on a set of standard test problems from the literature as well as on randomly generated dual transportation and assignment problems. Our computational experiments reveal that the proposed memoryless space dilation and reduction algorithm (VT-MSDR) and the proposed modification of the Polyak-Kelly cutting plane method (VT-PKC) provide an overall competitive performance relative to the other methods tested with respect to solution quality and computational effort. The r-Algorithm becomes increasingly more expensive with an increase in problem size, while not providing any gain in solution quality. The fixed dilation (with no reduction) strategy (VT-MSD) provides a comparable, though second-choice, alternative to VT-MSDR. Employing a two-step limited memory extension over VT-MSD sometimes helps in improving the solution quality, although it adds to computational effort, and is not as robust a procedure.
Master of Science

There are several important semiconductor devices in which the transport of carriers is controlled by punch-through space-charge effects. Examples include the Bipolar Mode Static Induction Transistor (BSIT), ultrasmall Punch-through MOSFETs, and BARITT diodes for microwave applications. The development of punch-through space-charge type of devices is a technology motivated by the demanding high density among the IC chips. This dissertation discusses a device which operates in a punch-through condition with space-charge control of currents. It is a two terminal device, which could be fabricated with no deviation from today's technology. The device structure is simple, with two n⁺ or p⁺ regions formed in p⁻ or n⁻ substrate, respectively. Punch-through space-charge limited structures both n⁺p⁻n⁺ and p⁺n⁻p⁺, were simulated using a general one-dimensional semiconductor device performance simulation program GESIM1 for dynamic and static analysis. The results of simulation show that the potential barrier height decreases with increasing applied potential and with a reduction of the spacing L between the n⁺ diffusion in an n⁺p⁻n⁺ structure. The resistance increases as the spacing L is increased. A two-dimensional analytical model of carrier transport in the device was developed. This model accounts for surface effects as well as the space-charge limited flow. Also, a one-dimensional model that includes mobile carriers effects on the device operation. Structures of various configurations were fabricated and tested. Electrical evaluations of these structures provided large value resistors in a remarkably small area compare to traditional integrated resistors. The resistance was observed to increase with the spacing L and with the resistivity of the starting substrate. These punch-through space-charge limited loads should have applications as an alternative approach for integrated resistors in high-speed VLSI applications. They can provide very small area, large value resistors based on the space-charge limiting action of the device. The range of resistance value is large, and small dimensions lead to small capacitance and fast switching times.

The aim of this bachelor's project was to find a typology for an apartment house in Dharavi in Mumbai, India. Dharavi is extremely congested and living space is scarce so the goal was to come up with good solutions for very small apartments that wouldn't be so costly and that each could be shared by a family. How could one make most of a very limited and shared living space? The family is a very important structure in the Dharavian sociaty and it seems like people rarely live alone or have their own space. The question whether individual space is important arose but is not answered in this project. However a home with a certain flexibility might be helpful if there's need to divide living space and change the home according to several people's wishes and needs. The idea of people's need of more spaces to the home than one single room was interesting during the project, as was the thought of taking advantage of the warm climate and not seal the home completely off from outdoors.  Important aspects of the project, except creating apartments that didn't have a big footprint, was to create homes that improved living conditions. These homes would need to be well ventilated and have sufficient light sources, among other qualities. The central part of the typology came to be, literally, a small courtyard to provide these mentioned qualities.

DSTC designs with high diversity and coding gains and efficient detection and code matrices optimization algorithms in cooperative MIMO networks are proposed in this thesis. Firstly, adaptive power allocation (PA) algorithms with different criteria for a cooperative MIMO system equipped with DSTC schemes are proposed and evaluated. Linear receive filter and maximum likelihood (ML) detection are considered with amplify-and-forward (AF) and decode-and-forward (DF) cooperation strategies. In the proposed algorithms, the elements in the PA matrices are optimized at the destination node and then transmitted back to the relay nodes via a feedback channel. Linear minimum mean square error (MMSE) receive filter expressions and the PA matrices depend on each other and are updated iteratively. Stochastic gradient (SG) algorithms are developed with reduced detection complexity. Secondly, an DSTC scheme is proposed for two-hop cooperative MIMO networks. An adjustable code matrix obtained by a feedback channel is employed to transform the space-time coded matrix at the relay node. The effects of the limited feedback and the feedback errors are assessed. An upper bound on the pairwise error probability analysis is derived and indicates the advantage of employing the adjustable code matrices at the relay nodes. An alternative optimization algorithm for the adaptive DSTC scheme is also derived in order to eliminate the need for feedback. Thirdly, an adaptive delay-tolerant DSTC (DT-DSTC) scheme is proposed for two-hop cooperative MIMO networks. An ML receiver and adjustable code matrices are considered for different DSTC configuration schemes subject to a power constraint with a DF cooperation strategy. An upper bound on the pairwise error probability and rank criteria analysis are derived and indicates the advantage of the proposed coding algorithm. Adaptive DT-DSTC algorithms are extended to the cooperative MIMO systems using an AF strategy and opportunistic relaying algorithms in order to achieve a delay-tolerant coding scheme combined with the optimal power allocation strategies.

Diese Arbeit leistet Beiträge im Bereich der deskriptiven Komplexitätstheorie. Zunächst beschäftigen wir uns mit der ungelösten Frage, ob es eine Logik gibt, welche die Klasse der Polynomialzeit-Eigenschaften (PTIME) charakterisiert. Wir betrachten Graphklassen, die unter induzierten Teilgraphen abgeschlossen sind. Auf solchen Graphklassen lässt sich die 1976 von Gallai eingeführte modulare Zerlegung anwenden. Graphen, die durch modulare Zerlegung nicht zerlegbar sind, heißen prim. Wir stellen ein neues Werkzeug vor: das Modulare Zerlegungstheorem. Es reduziert (definierbare) Kanonisierung einer Graphklasse C auf (definierbare) Kanonisierung der Klasse aller primen Graphen aus C, die mit binären Relationen auf einer linear geordneten Menge gefärbt sind. Mit Hilfe des Modularen Zerlegungstheorems zeigen wir, dass Fixpunktlogik mit Zählen (FP+C) PTIME auf der Klasse aller Permutationsgraphen und auf der Klasse aller chordalen Komparabilitätsgraphen charakterisiert. Wir beweisen zudem, dass modulare Zerlegungsbäume in Symmetrisch-Transitive-Hüllen-Logik mit Zählen (STC+C) definierbar und damit in logarithmischem Platz berechenbar sind. Weiterhin definieren wir eine neue Logik für die Komplexitätsklasse Logarithmischer Platz (LOGSPACE). Wir erweitern die Logik erster Stufe mit Zählen um einen Operator, der eine in logarithmischem Platz berechenbare Form der Rekursion erlaubt. Die resultierende Logik LREC ist ausdrucksstärker als die Deterministisch-Transitive-Hüllen-Logik mit Zählen (DTC+C) und echt in FP+C enthalten. Wir zeigen, dass LREC LOGSPACE auf gerichteten Bäumen charakterisiert. Zudem betrachten wir eine Erweiterung LREC= von LREC, die sich gegenüber LREC durch bessere Abschlusseigenschaften auszeichnet und im Gegensatz zu LREC ausdrucksstärker als die Symmetrisch-Transitive-Hüllen-Logik (STC) ist. Wir beweisen, dass LREC= LOGSPACE sowohl auf der Klasse der Intervallgraphen als auch auf der Klasse der chordalen klauenfreien Graphen charakterisiert.
This theses is making contributions to the field of descriptive complexity theory. First, we look at the main open problem in this area: the question of whether there exists a logic that captures polynomial time (PTIME). We consider classes of graphs that are closed under taking induced subgraphs. For such graph classes, an effective graph decomposition, called modular decomposition, was introduced by Gallai in 1976. The graphs that are non-decomposable with respect to modular decomposition are called prime. We present a tool, the Modular Decomposition Theorem, that reduces (definable) canonization of a graph class C to (definable) canonization of the class of prime graphs of C that are colored with binary relations on a linearly ordered set. By an application of the Modular Decomposition Theorem, we show that fixed-point logic with counting (FP+C) captures PTIME on the class of permutation graphs and the class of chordal comparability graphs. We also prove that the modular decomposition tree is definable in symmetric transitive closure logic with counting (STC+C), and therefore, computable in logarithmic space. Further, we introduce a new logic for the complexity class logarithmic space (LOGSPACE). We extend first-order logic with counting by a new operator that allows it to formalize a limited form of recursion which can be evaluated in logarithmic space. We prove that the resulting logic LREC is strictly more expressive than deterministic transitive closure logic with counting (DTC+C) and that it is strictly contained in FP+C. We show that LREC captures LOGSPACE on the class of directed trees. We also study an extension LREC= of LREC that has nicer closure properties and that, unlike LREC, is more expressive than symmetric transitive closure logic (STC). We prove that LREC= captures LOGSPACE on the class of interval graphs and on the class of chordal claw-free graphs.

Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2000.
Includes bibliographical references (leaves 91-96).
Facing disinvestment and unemployment, many places look to culture-based strategies for revitalization. Traditional models of culture-based community revitalization, however, have been criticized for contributing to gentrification, social polarization, and cultural discrimination. Communities seeking to avoid the contradictions of market oriented culture-based revitalization strategies can look to the efforts of community based organizations for models of how culture and the arts can contribute to revitalization without being limited to defining the benefits of their efforts solely in economic terms. In this thesis, I describe the efforts of one arts organization, Time & Space Limited (TSL), as an example of this process. Through an in-depth case study, I describe the role of TSL, a community-based arts organization, in creating an alternative strategy for community revitalization through the arts in Hudson, New York.
by Christian Willauer.
M.C.P.

A relatively new picosatellite standard, CubeSats have traditionally been used for simple educational missions. As CubeSats become more complex and utilize more complex sensors such as imagers, they gain enhanced credibility as satellite platforms. Imaging systems on CubeSats have the potential to be used for a variety of uses, such as earth and weather monitoring, attitude determination, and remote sensing. However the size and power limitations of CubeSats pose an interesting challenge to the design of a capable, robust imaging system. This thesis outlines the objectives and requirements of CP-3’s imaging system, and describes the development process and methods. Test results from the imaging system are included, as well as lessons learned gleaned from CP-3’s on-orbit operations. This document can serve as a guideline for other teams wishing to develop imaging systems. While other developers may have different requirements or constraints, this roadmap illustrates each of the many considerations that must be taken into account when designing an imaging system.

La thèse porte sur les mesures de courants transitoires limités par la charge d'espace dans des films minces organiques (épaisseur < 500 nm). Ce type de films est souvent utilisé dans des applications dans le domaine de l'électronique organique comme couches actives semi-conductrices. Le transport électrique dans ces films dépend en premier lieu du transport des porteurs de charge dans le milieu massif et de leur piégeage, mais aussi de l'efficacité de l'injection des porteurs de charges à partir des électrodes métalliques. L'ensemble est de plus conditionné par le taux de désordre inhérent aux matériaux organiques. L'approche qui consiste à utiliser la mesure de courants transitoires est extrêmement attractive car elle permet en principe de fournir une information sur tous ces aspects à l'issue d'un seul type de mesure. Dans ce cadre, trois contributions principales peuvent être dégagées de la thèse. 1) Tout d'abord, nous avons validé un montage expérimental qui utilise un amplificateur à transfert d'impédance pour la mesure des courants transitoires limités par la charge d'espace. Ce type de montage s'avère supérieur au circuit de pont électrique le plus largement utilisé jusqu'à maintenant car il présente une meilleure sensibilité en courant, une meilleure bande passante, et ne nécessite aucun réglage ni de la symétrie du pont ni de l'ajustement de la taille de l'échantillon. On a pu démontrer que le pic de courant de déplacement initial, qui sature l'amplificateur au tout début de la mesure n'introduit pas d'erreur dans la mesure de la mobilité. 2) Ensuite concernant l'étude plus spécifique du transport dans un dendrimère à base de tri-arylamine, les réponse en courant obtenues expérimentalement se sont avérées en bon accord avec le modèle de déplacement-diffusion. Cependant, la troisième leçon que nous avons apprise est que l'obtention d'un tel accord a nécessité que soient très bien définies les conditions initiales tant de l'expérience que de la simulation et qu'un modèle théorique le plus complet possible de l'échantillon soit considéré. Pour le dendrimère ce modèle a dû prendre en compte l'effet de la barrière au contact et les effets de piégeage. Un accord encore meilleur a été obtenu en intégrant de surcroit les effets de désordre. 3) La complète impossibilité d'obtenir un bon accord sans un modèle physique complet de l'échantillon indique que les paramètres liés au piégeage, à la barrière au contact et à la mobilité peuvent véritablement être ajustés sans aucune ambigüité. Ainsi, une caractérisation électrique complète en cohérence avec la simulation a pu être obtenue à l'issue d'un seul type de mesures. Les résultats obtenus, alliant à la fois amélioration technique et support numérique, témoignent de la grande utilité de cette technique de mesure de courant transitoire limité par la charge d'espace pour caractériser en détails le transport dans les films minces organiques
The thesis concerns space-charge-limited transient current measurements in thin (le500 nm) organic films. Such films find important applications in organic electronics, where they are referred to as organic semiconductor layers. Electrical transport in such films depends on bulk charge carrier transport and trapping, as well efficiency of charge carrier injection from electrodes. These, are all in turn depend on disorder inherent to organic materials. The transient measurement approach is very attractive, as it can, in principle, deliver information on all these aspects in one single measurement. In the thesis, three main contributions are presented. 1) A transimpedance amplifier based setup for space-charge-limited current transient measurement is validated. This type of setup is superior to the widely used bridge circuit, notably because of better current sensitivity, bandwidth, no need for bridge symmetry and no need for per sample adjustment. It is demonstrated that initial displacement current spike, which saturates the amplifier at the beginning of measurement, does not introduce error in the measurement of mobility. 2) A dendrimer molecule has been investigated. Experimental current responses are shown to be in agreement with the drift-diffusion model. However, obtaining agreement requires well defined initial conditions in experiment as well as in simulation, and also complete theoretical model of the sample. In the case of dendrimer, this model had to take into account both contact barrier and trapping effects. Furthermore, better agreement was obtained when taking disorder effects into account. 3) The impossibility of obtaining any agreement without complete physical model of the sample indicates that trapping, contact barrier and mobility parameters could be fitted without ambiguity. Therefore, complete electrical characterization consistent with simulation can be obtained using the transient technique. The results obtained further increase well known usefulness of transient space-charge-limited current characterization of thin organic films

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California
With every new spacecraft that is designed comes a greater density of information that will be stored once it is in operation. This, coupled with the desire to reduce the number of ground stations needed to download this information from the spacecraft, places new requirements on telemetry transmitters. These new transmitters must be capable of data rates of 320 Mbps and beyond. Although the necessary bandwidth is available for some non-bandwidth-limited transmissions in Ka-Band and above, many systems will continue to rely on more narrow allocations down to X-Band. These systems will require filtering of the modulation to meet spectral limits. The usual requirements of this filtering also include that it not introduce high levels of inter-symbol interference (ISI) to the transmission. These constraints have been addressed at CE by implementing a DSP technique that pre-filters a QPSK symbol set to achieve bandwidth-limited 320 Mbps operation. This implementation operates within the speed range of the radiation-hardened digital technologies that are currently available and consumes less power than the traditional high-speed FIR techniques.

Kyoto University (京都大学)
0048
新制・課程博士
博士(工学)
甲第14871号
工博第3139号
新制||工||1470(附属図書館)
27293
UT51-2009-K667
京都大学大学院工学研究科高分子化学専攻
(主査)教授 伊藤 紳三郎, 教授 長谷川 博一, 教授 金谷 利治
学位規則第4条第1項該当

We study two classes of stochastic systems, the limited processor sharing system and the multi-server system. They share the common feature that multiple jobs/customers are being processed simultaneously, which makes the study of them intrinsically difficult. In the limited processor sharing system, a limited number of jobs can equally share a single server, and the excess ones wait in a first-in-first-out buffer. The model is mainly motivated by computer related applications, such as database servers and packet transmission over the Internet. This model is studied in the first part of the thesis. The multi-server queue is mainly motivated by call centers, where each customer is handled by an agent. The number of customers being served at any time is limited by number of agents employed. Customers who can not be served upon arrival wait in a first-in-first-out buffer. This model is studied in the second part of the thesis.

This thesis presents an investigation of reactive transport of species in porous media, with the aim to understand better and predict the fate of radionuclide in engineered and natural barriers of future deep geological disposal facilities for nuclear waste. The work involves developments of several pore-scale models for simulating reactive transport by coupling convective, adsorptive and diffusive processes. Pore network models (PNM) are amongst the appealing approaches that provide a suitable description for dealing with mutable pore space structures. Such models have been used to describe conservative as well as reactive transport in saturated and unsaturated porous media. In the present thesis, pore network models based on a regular tessellation of truncated octahedral cells are proposed and developed to simulate mass transport in porous media with incomplete pore space information due to limitation of existing characterisation techniques. Bentonite and Opalinus Clay are selected to illustrate the methodology. The micro- and meso-structure of these clays and their effects on the transport behaviour are investigated. The research shows that the clays are anisotropic and heterogeneous with fast diffusion parallel to the bedding plane and slow diffusion perpendicular to the bedding plane. In addition, different types of species have different accessible porosity and macroscopic diffusion coefficients. The anisotropy and heterogeneity of clays are achieved by different length scales and percentage of pores in different directions in the pore network models. The transport behaviour of various species, including sorption and anion exclusion, is simulated and analyzed. The effect of sorption is simulated via changing the pore radii by a coarse grained mathematical formula or by a formula directly in each pore. The results are in good agreement with experimentally measured macroscopic (bulk) diffusivities for the materials studied, including anisotropic diffusion coefficients. This lends strong support to the physical realism of the proposed models. The developed methodology can be used for any micro and meso-porous material with known distribution of pore sizes. It can be extended to other pore space changing mechanisms, in addition to sorption, to derive mechanism-based evolution laws for the transport parameters of porous media.

Two sets of electrically small antennas in the form of coplanar meander dipoles have been designed and tested in this study. The meander dipoles are the anti-symmetrical and the symmetrical meander structures. Both sets were based on the 1.0 GHz linear halfwavelength dipole, i.e., all the meander dipole antennas have equal total arm lengths of 150.0 mm. Each set consists of several antennas, with different number of meander sections. The anti-symmetrical meander antennas were fabricated from copper (on RT/duroid substrate) whilst the symmetrical meander antennas were fabricated from copper, thick- and thin-film high temperature superconducting (HTS) materials. The first type of meander antennas was fed from underneath the circuit, through the substrate. The meander antennas are electrically small. However, as the physical size decreases, the frequency of operation increases resulting in an electrical size increase. The antennas were found to be inefficient, which is inherent to their small size. In addition, the far-field radiation pattern was close to that of a short dipole. Although they are inefficient as compared with large antennas, they can potentially have increased gain and increased efficiency with the use of superconducting material. This potential has been demonstrated by the second design, even though they have much smaller electrical and physical size. Coplanar strip (CPS) feeding line was employed to help reduce radiation pattern distortion. No matching network was designed because the antennas are reasonably well-matched to the input. Instead, a quarter-wavelength sleeve balun was incorporated to reduce the feeding loss and stray radiation. It also behaves as a matching network. The HTS symmetrical meander antennas were found to outperform the corresponding copper structures in terms of gain and efficiency. They also exhibit the supergain ratio in the range 10 to 45 over the corresponding copper structures. The symmetrical meander antennas operate at almost the same frequency as that of a linear halfwavelength dipole which has the same track length. This shows that the linear dipole can be miniaturised by meandering its radiating structure, whilst maintaining the frequency of operation. Numerical simulations were also done on all the designed antennas. The suitability of the HTS meander antennas for space-limited applications has been demonstrated.

The Reduction of engine noise, one of the primary noise sources in trucks and busses, is essential in order to fulfill various noise emission regulations such as ISO 362 [1]. At the same time, it is equally important to meet market demands in order to attract new customers while competing with other brands to lower overall noise levels. Sound power is a convenient descriptor of noise emissions when compared to sound pressure it is not dependent on the distance from the source and the surrounding environment. A number of standards for sound power measurement exist, requiring different methods, tools and environments. In engine development at Scania the sound power level is measured for different engine types for noise level determination and comparison purposes. Additionally, attempts to reduce noise through modifications of engine parts require many iterations in which sound pressures recorded at specific microphone positions are of primary interest. The necessity of running each engine at different speeds and load conditions with various modifications during development (combined with time restrictions) narrows down the choices to ISO 3745 which involves measuring sound power with stationary microphones. Despite ISO3745 apparent ease of use, prerequisites such as the number of microphones, the distance limitation of the microphones and free field conditions often pose a practical challenge. In Scania’s anechoic chamber it is impossible to meet these requirements due to limitations inherent to the room design such as size, poor absorption and limited space on the underside of the engine. This thesis comprises engine acoustic simulations in Nastran together with various measurements. Based on these, guidelines for power calculation have been developed taking into account the level of uncertainty and correction factors.

Space-charge effects play a dominant role in many areas of physics. In high-power microwave devices using high-current, relativistic electron beams, it places a limit on the amount of radiation a device can produce. Because the beam's space-charge can actually reflect a portion of the beam, the ability to accurately predict the amount of current a device can carry is needed. This current value is known as the space-charge limited current. Because of the mathematical difficulties, this limit is typically estimated from a one-dimensional theory. This work presents a two-dimensional theory for calculating an upper-bound for the space-charge limited current of relativistic electron beams propagating in grounded coaxial drift tubes. Applicable to annular beams of arbitrary radius and thickness, the theory includes the effect introduced by a finite-length drift tube of circular cross-section. Using Green's second identity, the need to solve Poisson's equation is transferred to solving a Sturm-Liouville eigenvalue problem, which is easily solved by elementary methods. In general, the resulting eigenvalue, which is required to estimate the limiting current, must be numerically determined. However, analytic expressions can be found for frequently encountered limiting cases. Space-charge effects also produce the fundamental collective behavior found in plasmas, especially in plasma sheaths. A plasma sheath is the transition region between a bulk plasma and an adjacent plasma-facing surface. The sheath controls the loss of particles from the plasma in order to maintain neutrality. Using a fully kinetic theory, the problem of a planar sheath with a single-minimum electric potential profile is investigated. Appropriate for single charge-state ions of arbitrary temperature, the theory includes the emission of warm electrons from the surface as well as a net current through the sheath and is compared to particle-in-cell simulations. Approximate expressions are developed for estimating the sheath potential as well as the transition to space-charge saturation. The case of a space-charge limited sheath is discussed and compared to the familiar Child-Langmuir law.

The work is concerned with the band-limited signal extrapolation using truncated series of prolate spheroidal wave function. Our aim is to investigate the extent to which it is possible to extrapolate signal from its samples taken in a finite interval. It is often believed that this extrapolation method depends on computing definite integrals. We show an alternative approach by using the least squares method and we compare it with the methods of numerical integration. We also consider their performance in the presence of noise and the possibility of using these algorithms for real-time data processing. Finally all proposed algorithms are tested using real data from a microphone array, so that their performance can be compared.

付記する学位プログラム名: グローバル生存学大学院連携プログラム
Kyoto University (京都大学)
0048
新制・課程博士
博士(工学)
甲第20341号
工博第4278号
新制||工||1662(附属図書館)
京都大学大学院工学研究科社会基盤工学専攻
(主査)教授 寶 馨, 教授 立川 康人, 准教授 佐山 敬洋
学位規則第4条第1項該当

Resistive random access memory (RRAM), based on a two-terminal resistive switching device with a switching element sandwiched between two electrodes, has been an attractive candidate to replace flash memory owing to its simple structure, excellent scaling potential, low power consumption, high switching speed, and good retention and endurance properties. However, due to the current limited understanding of the device mechanism, RRAMs research are still facing several issues and challenges including instability of operation parameters, the relatively high reset current, the limited retention and the unsatisfactory endurance. In this study, we investigated the switching mechanisms, conditions and applications of oxygen vacancy (Vo) filament formation in resistive memories. By studying the behavior of conductive Vo nanofilaments in several metal/oxide/metal resistive devices of various thicknesses of oxides, a resulting model supported by the data postulates that there are two distinct modes of creating oxygen vacancies: i) a conventional bulk mode creation, and ii) surface mode of creating oxygen vacancies at the active metal-dielectric interface. A further investigation of conduction mechanism for the Vo CF only based memories is conducted through insertion of a thin layer of titanium into a Pt/ Ta2O5/Pt structure to form a Pt/Ti/ Ta2O5/Pt device. A space charge limited (SCL) conduction model is used to explain the experimental data regarding SET process at low voltage ranges. The evidence for existence of composite copper/oxygen vacancy nanofilaments is presented. The innovative use of hybrid Vo/Cu nanofilament will potentially overcome high forming voltage and gas accumulation issues. A resistive floating electrode device (RFED) is designed to allow the generation of current/voltage pulses that can be controlled by three independent technology parameters. Our recent research has demonstrated that in a Cu/TaOx/Pt resistive device multiple Cu conductive nanofilaments can be formed and ruptured successively. Near the end of the study, quantized and partial quantized conductance is observed at room temperature in metal-insulator-metal structures with graphene submicron-sized nanoplatelets embedded in a 3-hexylthiophene (P3HT) polymer layer. As an organic memory, the device exhibits reliable memory operation with an ON/OFF ratio of more than 10.
Ph. D.

This thesis concerns with electrical and optoelectical properties of thin organic semiconductor layers. In the research, organic electroluminescent devices were prepared and the effect of illumination and inclusion of organic interlayers, that act as alternative electrodes, on charge injection and transport were investigated on them by means of electrical measurement and impedance spectroscopy. On the basis of measured data, the thesis attempts to determine materials best suited for interlayers, which could make an improvement of electric properties of electroluminescent devices possible. The sence of using a combination of direct current measurement and impedance spectroscopy was also discussed in the thesis.

Neste trabalho analisa-se o problema do transporte do feixe de elétrons em canhões de elétrons, estruturas periódicas de ímãs permanentes e em coletores de simples e múltiplos estágios. Essa análise é de relevância em projetos de dispositivos de micro-ondas de potência dos tipos amplicador klystron e válvula TWT. Determina-se a dinâmica das partículas a partir da solução da equação da trajetória que é derivada da força de Lorentz e da conservação de energia. A equação da trajetória obtida é diferencial de segunda ordem, não-linear e independentemente do tempo para o potencial generalizado. Utiliza-se o método de Runge-Kutta de 4a Ordem para integrar a equação da trajetória das partículas. Obtém-se o potencial escalar elétrico a partir da solução da equação de Poisson. Numericamente, obtêm-se os po- tenciais escalares elétricos e magnéticos, por meio do Método de Elementos Finitos (MEF). Ao longo do movimento de uma partícula, obtida a partir da solução da equação da trajetória, deposita-se carga elétrica. Utilizam-se macropartículas, uma vez que é praticamente impossível modelar cada partícula do problema, a partir do método Partícula na Célula (Particle in Cell - PIC). Neste caso, tem-se um problema acoplado para o potencial escalar elétrico e as trajetórias das macropartículas, uma vez que, as trajetórias das macropartículas dependem dos potenciais e estes, por sua vez, dependem das trajetórias. À convergência deste problema acoplado utiliza-se o Método das Aproximações Sucessivas (MAS). A plataforma desenvolvida, baseada nos métodos acima, compõe-se de duas ferramentas computacionais. A primeira, XMGUN, dedica-se ao projeto de: canhões de elétrons com grades e grades de sombreamento; e coletores de simples e múltiplos estágios considerando, ainda, a emissão de elétrons secundários. A segunda, XMAGUN, volta-se ao projeto de estruturas periódicas com ímãs permanentes. Afere-se o desempenho da ferramenta computacional XMGUN com o diodo plano de Pierce operando na condição em que a corrente é limitada pelas cargas espaciais. Por sua vez, verica-se o desempenho do XMAGUN por meio de simulações com estruturas do tipo PPM separadas pelo vácuo e na presença de pole pieces. Os resultados obtidos em todas as simulações convergiram satisfatoriamente para as soluções analíticas. Utilizando o XMGUN, projeta-se um canhão de elétrons com 30 kV de tensão de anodo e uma perveância de 1,37 Perv com capacidade de fornecer uma corrente elétrica de 7,1 A. Esse canhão tem uma malha com 2796 elementos e 5057 nós. As principais características geométricas do canhão de elétrons são: raio do catodo rc=14,6 mm; raio do disco do catodo rk =6,2 mm; e ângulo do eletrodo de focalização = 37. Neste caso, a velocidade transversal normalizada e o alcance do feixe zw observados são de 0,068 e 26,88 mm respectivamente. Obtém-se uma concordância superior a 93% em corrente e perveância com o EGUN. Utilizando, ainda, o XMGUN, são simulados coletores de simples e múltiplos estágios. O coletor de simples estágio apresenta 1612 nós e 2969 elementos, e o de 4 (quatro) estágios, 2496 nós e 4257 elementos. As tensões dos eletrodos do 1o, 2o, 3o e 4o estágio são de 9,45 kV, 8,65 kV, 6,45 kV e 3,45 kV respectivamente. Durante as simulações, devido à emissão de elétrons secundários, observa-se, para o coletor de simples estágio, macropartículas penetrando na região de deriva, fenômeno este indesejado, e não observado para o coletor de 4 (quatro) estágios. Considerando o XMAGUN, projeta-se um arranjo periódico com pole pieces e 5 (cinco) ímãs permanentes, capaz de fornecer um campo magnético, no centro da estrutura, de 0,42 T. Neste caso, a geometria do arranjo periódico obtida é: raio interno rm1 e externo rm2 do ímã permanente são iguais a 3,5 mm e 7,5 mm respectivamente; raio externo do pole piece r3 = 7,5 mm ; raio interno rf1 e externo rf2 da ponteira do pole piece são 1,6 mm e 3,05 mm respectivamente; espessura do ímã permanente T=2,95 mm; período magnético L =8,5 mm. A remanência do ímã permanente utilizada é de Br=0,85 T. A malha dessa estrutura periódica magnética apresenta pouco mais de 20.000 nós e 40.000 elementos.
In this paper we analyze the problem of transport of the electron beam in electron guns, periodic arrays of permanent magnets and collectors of simple and multiple stages. This analysis is of relevance in the design of power microwave devices such as klystron amplier and TWT valve. The dynamics of particles is determined from the solution of the equation of the trajectory that is derived from the Lorentz force and energy conservation law. The equation of the trajectory obtained is differential of second-order, non-linear and time independent for the generalized potential. It is used the Runge-Kutta 4th order method to integrate the equation of the trajectory of the particles. The electric scalar potential is obtained from the solution of the Poisson equation. Numerically, we obtain the electric and magnetic scalar potentials, using the Finite Element Method (FEM). Throughout the motion of a particle, obtained from the solution of the equation of the trajectory, electrical charge it is deposited. Macroparticles are used, since it is virtually impossible to model each particle of the problem, based on Particle in Cell scheme (Particle in Cell - PIC). In this case, there is a coupled problem for the electric scalar potential and the trajectories of the macroparticles, since these trajectories depend on the potential and the potential, in turn, depends on the trajectories. In order to abtain the convergence of this coupled problem, it used the Method of Successive Approximations (MSA). The platform developed, based on the above methods, consists of two computational tools. The rst, XMGUN, is dedicated to the project of: electron guns with grids and shadow-grids, and collectors of simple and multiple stages, where secondary electrons emission is considered. The second, XMAGUN, is used to the design of periodic permanent magnets structures. The XMGUN was benchmarked against the plan Pierce diode under space charge limited condiction. In turn, the XMAGUN was benchmarked against PPM like structures, separated by a vacuum and in the presence of pole pieces. The results, in all simulations, converged satisfactorily to the analytical solu- tions. Using XMGUN, it is designed an electron gun with 30 kV anode voltage, 1.37 Perv capable of supplying an electric current of 7.1 A. This gun has a mesh with 2796 elements and 5057 nodes. The main geometric characteristics of the electron gun are: cathode radius rc = 14.6 mm; cathode disc radius rk = 6.2 mm; and half cone angle = 37. In this case, the normalized transverse velocity and beam-waist distance from anode zw are 0.068 and 26.88 mm respectively. An agreement above 93% in current and perveance is found when compared with EGUN. XMGUN is also used to simulate single and multi stage collectors. The single-stage collector has 1612 nodes and 2969 elements, while the 4 (four) stages collector has 2496 nodes and 4257 we elements. The collector electrode voltages of the 1st, 2nd, 3rd and 4th stage are 9.45 kV 8.65 kV 3.45 kV 6.45 kV, respectively. During the simulations, due to yield of secondary electrons, for the single stage collector, it is observed macroparticles entering into the drift region, a phenomenon unwanted, and not observed for the 4 (four) stage collector. Whereas XMAGUN is projected at a periodic arrangement with pole pieces and 5 (ve) permanent magnets, capable of providing a magnetic eld in the center of the structure was 0.42 T. In this case, the geometry of the periodic arrangement is obtained: inner and outer radius of the permanent magnet rm1 = 3.5 mm and 7.5 mm respectively rm2 =; outer radius of the pole piece r3 = 7.5 mm, internal radius and external tip of the pole piece rf1=rf2 =1.6 mm and 3.05 mm respectively; permanent magnet thickness T = 2.95 mm magnetic period L = 8.5 mm. The remanence of the permanent magnet used is Br = 0.85 T. The net periodic structure of magnetic features little more than 20,000 nodes and 40,000 elements.

Mestrado em Engenharia Eletrónica e Telecomunicações
Com a crescente necessidade de transporte de mercadoria como resultado da globalização económica, é importante o melhoramento dos processos e procedimentos das operações logísticas como o carregamento e descarregamento de mercadoria, por forma às corporações aumentarem a sua vantagem competitiva e rentabilidade. Esta dissertação explora e apresenta dois temas relacionados com processos logísticos: Posicionamento de volumes e tecnologias de deteção para monitorização de mercadorias. Uma heurística foi desenvolvida para atribuição e posicionamento 3D de volumes dentro de contentores seguindo uma estratégia de colocação que produz soluções verticalmente estáveis e com um alto grau de compactação. Desenvolveram-se dois protótipos usando tecnologia de deteção capaz de medição de volumes, varrimento por laser e visão estereoscópica por computador, como fundação para um sistema para monitorizar o carregamento e descarregamento de mercadorias. Estes sistemas pretendem providenciar assistência para os operadores logísticos na aplicação de normas e identificação de potenciais problemas. Os resultados obtidos pela heurística são promissores, mostrando que um conjunto de simples regras de posicionamento de caixas consegue obter uma boa percentagem de ocupação de volume do contentor. Ambos os protótipos de deteção apresentaram bons resultados nos testes de laboratório, com o protótipo de visão estereoscópica provando ser o mais preciso e fiável para potencial desenvolvimento em uma aplicação a ser instalada em contentores. Esta dissertação conclui com observações acerca de futuros melhoramentos e desenvolvimentos para o trabalho implementado.
With the ever necessity of cargo transportation as the results of economic globalization, it is important to improve the processes and procedures of logistic operations such as cargo loading and unloading, in order for corporations to increase their competitive advantage and profitability. This dissertation explores and presents two subjects related with logistic processes: Volume placement and sensing technologies for cargo monitoring. A heuristic was developed for 3D volume assignment and placement inside containers following a positioning strategy that produces vertically stable solutions with a high degree of compactness. Two prototypes using sensing technology capable of volume measurement, laser range finding and computer stereo vision, were developed as a foundation for a system for monitoring the loading and unloading of cargo. These systems aim to provide assistance to logistic operators on the application of standards and identification of potential issues. The obtained results on the heuristic are promising, showing that a simple set of rules for placement of boxes can achieve a good occupation percentage of the container’s volume. Both sensing prototypes showed good results on lab tests with the stereo vision prototype proving to be the most accurate and reliable for potential further developments into an application to be installed in containers. This dissertation concludes with remarks regarding future improvements and developments for the implemented work.

A presente dissertação propõe uma revisão e reflexão críticas ao exercício de projeto entregue no “Concurso Prémio Universidades Trienal de Lisboa Millennium BCP”, fundamentadas no estudo e análise dos limites do espaço público na relação física, visual e metafórica com a sua envolvente. Neste contexto, o ritmo de crescimento desapropriado e desequilibrado entre o núcleo urbano de Sines e o seu complexo industrial e portuário originaram a separação entre a cidade e a sua frente mar, um “virar as costas” ao meio que, desde a sua origem, foi o seu principal recurso de fomentação. Esta dessincronização provocou um conflito entre sistemas (urbano, natural e industrial), motivando a rutura e parcialização do território sineense. A falta de integridade provocou o aparecimento de espaços obsoletos e expetantes, lugares que, aparentemente esquecidos, provocam desordem sobre a paisagem, assim como incapacidade de atração da mesma. Desta forma, a resposta à problemática da investigação desenvolvida é apresentada com base em novas abordagens e perspetivas que integram e evidenciam os limites na definição de um determinado lugar, de uma cultura e das ações a desenvolver; ABSTRACT: The following thesis suggests a revision and critical reflexion over the undertanking exercise delivered in the “Concurso Prémio Universidades Trienal de Lisboa Millennium BCP”, based in the study and analysis of the public spaces limits in the physical, visual and metaphorical link with its surroundings. In this context, the unappropriated and uneven flow of growth between the urban core of Sines and its industrial complex comprising the harbour created the separation between the city and its ocean front, an authentic “back out” to the surroundings, responsible for its first resource of fomentation since the dawn of times. This desynchronization creates a conflict between systems (urban, natural and industrial), motivating the rupture and fragmentation of Sines’ territory. The lack of integrity caused the appearance of obsolete and expectant spaces, places that, apparently forgotten, generate chaos over the landscape as well as the inability to lure and create appealing factors. Thus, the answer to the problematic of the developed investigation is provided based in new approaches and perspectives that integrate and highlight the limits in the definition of a certain place, a certain culture and the actions to develop.

O presente trabalho de projecto, resulta da leitura do território e do lugar de Sines, inserida numa primeira fase de reflexão promovida por um concurso nacional de arquitectura, culminando num projecto, plano de acção, que em grande medida pretende clarificar aspectos fenomenológicos, de escala e arquitectura, para isso referências e casos de estudo, suportam a acção sugerida, esta revista e direccionada para o tema de interesse, espaço público e a tipologia arquitectónica do rossio. O rossio espaço vazio é o organizador do conjunto sugerido, a sua mais íntima relação com as premissas de projecto de conectar e aproximar diferentes partes da cidade, expressam a importância de o abordar de forma mais individual. As construções portuárias, atribuíram novos valores e características ao território, alguns desacertos continuam a carecer de um ajuste, profundas alterações topográficas e manifestas fronteiras administrativas, não promovem um sentido democrático e acessível, e a introdução de um lugar capaz de aproximar paisagens, industrial e urbe, sendo ele próprio espaço que suporta actividades de ambas, deve constituir a orientação do trabalho. A reflexão teórica e prática sugere espaço público, na relação entre diferentes limites, um rossio na frente-de-água, as possibilidades particulares do proposto, pretendem se expressar por conceitos demonstráveis e outros perceptíveis pela especificidade do lugar, programas, funções e cenários eventuais; ABSTRACT: The present work of project, results from the analysis of the territory and the place of Sines, inserted in a first stage of reflection promoted by a national architectural competition. It originated a project and an action plan, which largely aims to clarify phenomenological aspects, scale and architecture. References and case studies support the suggested action, wich was reviewed and focused on the theme of interest, public space and the architectural typology of the terrace. The terrace empty space is the organizer of the suggested set, its most intimate relationship with the project premises of connecting and approaching different parts of the city, expressing the importance of approaching it in a more individual way. The port constructions have given new values and features to the territory, some misadventures continue to lack an adjustment, deep topographical changes and manifest administrative boundaries, do not promote a democratic and accessible sense, and the introduction of a place capable of approaching landscapes, industrial and space being itself the space that supports activities of both, should constitute the orientation of work. The theoretical and practical reflection suggests public space, in the relation between different limits, a terrace in water front, the particular possibilities of the proposed work, intend to express themselves by demonstrable concepts and others perceptible by the specificity of the place, programs, functions and eventual scenarios.

Dissertação de Mestrado para obtenção do grau de Mestre em Arquitectura, apresentada na Universidade de Lisboa - Faculdade de Arquitectura.
Desde que o Homem precisou de se proteger contra os elementos naturais adversos que surgiu a necessidade de criar uma estrutura que fosse capaz de o abrigar – esta foi a primeira forma de casa, dado que supria apenas essa necessidade. Ora, essa função é ultrapassada quando essa estrutura artificial, no meio da natureza, começa a ser personalizada por quem a utiliza, sendo nesse momento que surge a CASA. Desde cedo que ela é factor de estabilidade e segurança, sendo por isso factor fulcral na identificação do Homem como pessoa. Assim sendo, se o Arquitecto for capaz de compreender a importância que este elemento tem para a vida de cada um, ser-lhe-á possível proceder ao desenho de projecto de uma forma mais consciente, de modo a que o utilizador final se identifique com ela e a passe a reconhecer como sua. O acto de DESENHAR A CASA, que toma em consideração os seus moradores e percebe o que é realmente necessário que nela exista para que o sentimento de apropriação e pertença se desenvolva, torna-se ainda mais importante quando se trata de uma situação de realojamento social, tendo em conta que acabará inevitavelmente por ter que haver uma mudança de lugar íntimo – a CASA. No Bairro do Barruncho é imperativa a necessidade de uma solução arquitectónica de habitação que solucione a situação de precariedade infraestrutural. Assim sendo, foi criada e desenvolvida uma relação próxima com os moradores, de modo a que estes identificassem as fragilidades – que devem ser corrigidas – e as potencialidades – que serão utilizadas como ponto de partida para uma integração social dos mesmos na sociedade – do próprio Bairro. Deste modo DESENHAR DA CASA acaba por implicar alguma reestruturação do Bairro, porque ele por si só é a CASA dos seus moradores.
ABSTRACT: From that moment Man felt the need to protect himself from the adverse natural elements, rose the urge to create a structure which would be capable of sheltering him – this was the first form of house, since it only satisfied that need. Now, that function is surpassed when that artificial structure, in the middle of nature, begins to be customized by those who use it, that being the moment of the creation of a HOUSE. From the beginning of times it is seen as a stability and safety factor, hence being a fundamental factor in the identification of Man as person. Thus, if the Architect is able to understand the importance that this element has to the life of each one, it will be possible for him or her to make the project design in a more conscious way, enabling the final user to identify him or herself with it and as his or her own. The act of DRAWING THE HOUSE, which takes in to account their users and realizes what really must be in it in order to allow the development of the senses of ownership and belonging, becomes even more important when dealing with a situation of social resettlement, given that inevitably there will have to exist a shift of their intimate place – HOME. In Bairro do Barruncho, the need for an architectonic housing solution that ends the situation of infra-structural precariousness is of the utmost importance. Thus was created and nurtured a close relationship with the residents, in such a way that they would identify the fragilities – which must be corrected – and the potentialities – which will be used as a starting point towards the social integration of themselves in the society – the Neighborhood itself. Hence, DRAWING THE HOUSE will eventually lead to some restructuring of the District, as it stands by itself as the HOME of its residents.

Propomos um enfoque sobre a requalificação da Praça Roosevelt na perspectiva da produção do espaço relacionando os campos da dominação e o da apropriação. As transformações nos usos e funções dos lugares revelam o movimento do capital reestruturando a cidade a sua imagem. Propomos uma análise do espaço público enfocando como o mesmo é absorvido pelos diferentes ciclos do capital. Neste sentido, a Praça Roosevelt pode ser entendida como metonímia dos ciclos de modernização que configuraram a própria metrópole. Entre o campo da dominação política e da acumulação do capital temos que o espaço público caminha no sentido do controle e da privatização, perdendo seu caráter de efetividade social. No embate entre propriedade e apropriação emergem os conflitos no espaço público. Embora a tendência seja uma limitação do uso de forma cada vez mais recrudescedora, enquanto possibilidade, a vida social pode se insurgir reclamando seu lugar no espaço público.
We propose a focus upon the recovery of Roosevelt Square within the prospect of producing space within the contexts of possession and appropriation. The transformations in the uses and functions of these spaces reveal the movement of capital, restructuring the city in its fashion. We propose an analysis of public spaces focusing on how they are absorbed within different cycles of capital investment. In this sense Roosevelt Square may be understood as a synecdoche of the cycles of modernization that have shaped the metropolis. Between the fields of political power and that of accumulation of capital we would have to say that public spaces are moving in the direction of control and privatization, losing their character in terms of social importance. In the battle between property acquisition and public appropriation conflicts emerge within public spaces. Although the trend is for ever more persistent limitation of their possible uses, social activities may take place there, reclaiming their place in public spaces.

Tese de Mestrado em Arquitectura
O presente trabalho teve como principal objectivo uma reflexão acerca da problemática da adequação urbana que existia no caso de estudo do bairro da Cova da Moura, mais concretamente, da falta de continuidade que está patente nos limites do bairro. A articulação que me propus criar para explicar da melhor maneira o tema em questão, passou numa primeira instância pela definição do que é um limite, e de como este se define na Cova da Moura. Partindo então dessa premissa, analisei, através da obra de sociólogos, arquitectos e filósofos, os limites físicos e sociológicos que podemos definir para este mesmo lugar, com o propósito de clarificar de um modo adequado a especificidade social vivida na Cova da Moura. Funcionando então como base teórica e conceptual para a elaboração do ponto chave deste trabalho, a vertente prática associada a um Projecto de Arquitectura, elaborei uma solução construída para o problema que era vivido num dos limites existentes no bairro, na falta de articulação causada pela linha ferroviária existente a Norte da Cova da Moura, através de um edifício que permite a ligação entre as cotas adjacentes à estação. Chega-se então à conclusão que nós, enquanto Arquitectos, temos a obrigação de resolver e acima de tudo pensar este tipo de problemas no tecido urbano, caso contrário contribuímos unicamente para complexificar o que já é difícil de resolver. Por esta razão assistimos a situações em que a Arquitectura não resolve os problemas associados a determinado território, o que resulta num condicionamento da qualidade da experiência arquitectónica por parte dos utilizadores.
The current work had, as the main goal, a thought about the urban suitability that exists in the case study of Cova da Moura, more specifically, the lack of continuity that are displaced around the limits of this quarter. The organization that I’ve created to explain in a correct way this theme, passed by, firstly by a definition of the limit itself, and how it is exactly defined in Cova da Moura. Starting on this assumption, I’ve analyzed, through the work of some sociologists, architects and philosophers, the physical and sociological limits that we can define for this place, with the purpose of clarifying in an adequate way the social specificity that is lived in this quarter. Functioning as a theoretical and conceptual basis for the elaboration of this work, the practical side of an Architectural Project, I’ve created a built solution for the living problem around the boundaries of the quarter. on the lack or connection existing North of Cova da Moura, through a building capable of linking the two different heights on both side of the railroad. We can effectively conclude that we, as forming architects, have the obligation to solve and, above all think, this kind of urban tissues problems, otherwise we’ll only turn the problem even harder to solve. For this reason we can figure lots of situations in which Architecture does not solve the problems related with the territory, conditioning the quality of the users architectural experience.

This thesis studies the problem of modeling life-limited spare units in a steady-state scenario. This means that units that have a predefined lifespan are to be modeled in a scenario where all conditions are kept constant and all transients have faded out. OPUS10 is a spare parts optimization software developed by Systecon AB. There is no way to explicitly model the life-limited units in OPUS10, although there are different approximate models that are built on adjustments of the failure rate and repair fraction or the definition of preventive maintenance. The objective of this thesis is to analyze the usage of life-limited items in real life and to investigate what approximated models different OPUS10 users will utilize in their modeling of life-limited units. Furthermore, the objective is to analyze the consequences of the approximated models and to investigate the possibility of an improved model. The results show that the main interest when choosing which approximated model to use is the type of life limit. There are three different types of operating time life limits investigated. Either the unit is discarded immediately after the life limit is reached, or it is instead discarded at the next failure. There is also the possibility of resetting of the life limit timer at each maintenance. In all three cases, it is shown that if choosing the most fitting approximate model, the results are very accurate. If the life limit is instead measured in calendar time, even the best approximation will give an under-estimation of the expected number of backorders. It is also shown that most of the OPUS10 users model life-limited units as preventive maintenance with discard, which is not the best approximation in any of the types of life limits.

La conception de cellules solaires organiques de type hétérojonction en volume a été proposée pour la première fois en 1990. Ces dispositifs sont composés d’un mélange de polymères conjugués, donneurs d’électrons, et de fullerènes, accepteur d’électrons, et ont pour la première fois permis d’atteindre un rendement de conversion énergétique significatif (de l’ordre de 2%) avec des semi-conducteurs organiques. Dans ce contexte, cette thèse a porté sur l'étude approfondie d’une série de molécules donneurs d’électrons de forme d’haltère, dont le groupement planaire est l’unité triazatruxène (TAT) et le cœur déficient en électrons le thienopyrroledione (TPD). Les molécules de cette série se différencient par la nature des chaînes alkyles, attachées à l’unité centrale et aux unités TAT. Plus précisément, la relation entre la nature des chaînes latérales et les propriétés moléculaires et thermiques de ces molécules en forme d’haltère ont été étudiées en détail. L'impact des chaînes alkyles sur la morphologie en film mince à l’échelle nanométrique a également été étudié. Afin de mieux comprendre l’influence de la microstructure des films minces (constitués soit uniquement des molécules donneuses soit de mélanges molécules/fullerènes), le transport de charge dans le plan du film et perpendiculairement au plan ont été mesurées en fonction de la phase (amorphe, cristalline, …) du matériau. Des cellules solaires BHJ en mélange avec le dérivé de fullerène ont également été réalisées
The prospective conception of electron-donor/electron-acceptor (D/A) bulk heterojunction solar cells was first reported in 1990s, which blended the semiconducting polymer with fullerene derivatives, enhancing the power conversion efficiency. Since then, interests on this domain has been increasing continuously, and the efficiencies of BHJ solar cells have been increased dramatically. In this context, this thesis focuses on the study of a series of dumbbell-shaped small molecule donors, based on a highly planar unit called triazatruxene. The only difference between those molecules is the side-chains attached to central units and TAT units. As a consequence, the relationship between side chains nature and optoelectronic and structural properties of our TAT-based dumbbell-shaped molecular architecture will be investigated in detail. The impact of the alkyl chains on the molecular and thin film properties was also studied, with a particular emphasis put on microstructure and charge transport aspects. In-plane and out-of-plane charge carrier transport, with pure molecules and blend with fullerene, are measured in different systems. BHJ solar cells in blend with fullerene derivatives were also realized

Thesis (M.S. in Astronautical Engineering)--Naval Postgraduate School, December 2002.
Thesis advisor(s): Christopher M. Brophy, Jose O. Sinibaldi. Includes bibliographical references (p. 45-47). Also available online.

Nous présentons des inégalités fonctionnelles pour les processus ponctuels. Nous prouvons une inégalité de Sobolev logarithmique modifiée, une inégalité de Stein et un théorème du moment quatrième sans terme de reste pour une classe de processus ponctuels qui contient les processus binomiaux et les processus de Poisson. Les preuves reposent sur des techniques inspirées de l'approche de Malliavin-Stein et du calcul avec l'opérateur $Gamma$ de Bakry-Émery. Pour mettre en œuvre ces techniques nous développons une analyse stochastique pour les processus ponctuels. Plus généralement, nous mettons au point une théorie d'analyse stochastique sans hypothèse de diffusion. Dans le cadre des processus de Poisson ponctuels, l'inégalité de Stein est généralisée pour étudier la convergence stable vers des limites conditionnellement gaussiennes. Nous appliquons ces résultats pour approcher des processus Gaussiens par des processus de Poisson composés et pour étudier des graphes aléatoires. Nous discutons d'inégalités de transport et de leur conséquence en termes de concentration de la mesure pour les processus binomiaux dont la taille de l'échantillon est aléatoire. Sur un espace métrique mesuré quelconque, nous présentons un développement de la concentration de la mesure qui prend en compte l'agrandissement parallèle d'ensembles disjoints. Cette concentration améliorée donne un contrôle de toutes les valeurs propres du Laplacien métrique. Nous discutons des liens de cette nouvelle notion avec une version de la courbure de Ricci qui fait intervenir le transport à plusieurs marginales
We present functional inequalities and limit theorems for point processes. We prove a modified logarithmic Sobolev inequalities, a Stein inequality and a exact fourth moment theorem for a large class of point processes including mixed binomial processes and Poisson point processes. The proofs of these inequalities are inspired by the Malliavin-Stein approach and the $Gamma$-calculus of Bakry-Emery. The implementation of these techniques requires a development of a stochastic analysis for point processes. As point processes are essentially discrete, we design a theory to study non-diffusive random objects. For Poisson point processes, we extend the Stein inequality to study stable convergence with respect to limits that are conditionally Gaussian. Applications to Poisson approximations of Gaussian processes and random geometry are given. We discuss transport inequalities for mixed binomial processes and their consequences in terms of concentration of measure. On a generic metric measured space, we present a refinement of the notion of concentration of measure that takes into account the parallel enlargement of distinct sets. We link this notion of improved concentration with the eigenvalues of the metric Laplacian and with a version of the Ricci curvature based on multi-marginal optimal transport

Esta dissertação é consequência de uma pesquisa em poéticas visuais que aborda e articula modos de intensificação das potencialidades do corpo humano como abertura, meio de inscrição e disseminação da vida como obra em processo. O corpo é pensado como lugar e limite de onde o sentido parte, partilha, colide e compõe com outros corpos. O trabalho se constitui em cinco volumes, ao mesmo tempo autônomos e vinculados entre si. Em cada um deles, dimensões da experiência vital, conjugadas a procedimentos artísticos, são exploradas e apresentadas de diversas maneiras. Assim, a soma de segmentos que resultam no conjunto da dissertação abre um espaço de relações contíguo ao deslindar do seu próprio contorno, canteiro que se mede e se faz simultaneamente.
This dissertation stems from research conducted on visual poetics, which starts with an overview and analysis of ways of intensifying the human body’s potential, and proceeds to explore ways of inscribing and disseminating life as a work in progress. The body is reflected as a place and a limit from which meaning originates, splits, collides, and creates with other bodies. This paper consists of five volumes, all of which are independent, yet connected at the same time. In different ways, each volume presents and explores life combined with artistic procedures. Thus, the sum of all the presented elements that come together in this dissertation, opens a space of relations, contiguous to the unraveling of its own contour like a workspace that is simultaneously being measured and created.

The central claim of the thesis is that contemporary painting can be productively considered and made through a renewed investigation of syntax. Beginning with a detailed examination of Jonathan Lasker's work, I argue that a recomposed concept of syntax as a critical method distinguishes what I term 'syntactical painting' from modernist formalism and postmodern quotation. Looking to Rosalind Krauss' writing on Pablo Picasso, I discuss the mutability of the sign; and through Tomma Abts' use of shadow I rework Clement Greenberg's pejorative term 'homeless representation' into a positive avenue of enquiry. I then consider an alternative idea of syntax, identifiable in Daniel Buren, Robert Ryman and Wade Guyton, that works from outside of the frame. Here, I contend that using real space to critique painting fails to replace internalised invention, and that a continued resistance towards illusion has run its course. In the text, I rethink modernist assertions of objectness over imagery, along with Michael Fried's absorption/theatricality concepts, to propose Duccio's diagrammatic space and Frank Stella's reconciliation of flatness with the frame as models for painting whereby the viewer can clearly experience syntax. Such discussions reveal how certain meta-reflexive operations, which are otherwise largely neglected by critical discourse, can be reappraised via syntactical painting. The thesis accompanies my painting practice, in which I use soft films of transparent oil to pictorialise the materiality of the prepared field. The paintings are meticulously rendered, and appear as though drawn or printed. I use bands of colour to bring a particular delicacy to the figuring of the frame, which is achieved through transparency and trompe l'oeil illusion. I often conceive of painting as a two-dimensional stage space that curtails fictive distance as it represents it, and as an abstract diagram for the re-presentation of photography's installation shot of painting and the gallery.

Cette thèse contribue à l’étude des effets géants et anormaux de piézo-résistance (PZR) observés dans le nano-silicium. La PZR du silicium massif est devenue la clé de voûte de nombreuses technologies dont l’industrie micro-électronique vise des dispositifs de dimensions nanométriques. Il est donc logique d’investiguer la PZR du silicium à ces échelles spatiales où ont été révélé l’existence d’une PZR géante et d’une PZR d’amplitude « normale » mais de signe anormale. Cependant l’origine de ces effets reste peu claire et dans certains cas, leur véracité a été remise en cause. L’ensemble de ces effets semble corrélé à un appauvrissement en porteurs libres où le courant devient limité par la charge d’espace (en anglais SCLC). Pour mettre en lumière la dépendance en contrainte mécanique des taux de capture et d’émission de porteurs libres sur des pièges liés aux défauts cristallins, nous utilisons la technique de spectroscopie d’impédance qui, alliée à la spectroscopie de photoémission, suggère que les pièges en question sont ceux liés aux défauts intrinsèques de surface. La PZR géante n’est observée qu’en dehors du régime stationnaire. Dans le régime stationnaire dans laquelle se situe l’ensemble des études précédentes, bien qu’une PZR géante ne soit pas observée, une PZR de signe anormale est mesurée dans le silicium où une densité de défauts bien choisis a été introduite. Nous démontrons que cette dernière est due à un changement de type de porteur majoritaire induit par la tension appliquée en régime SCLC. Le chapitre 1 aborde l’historique de la PZR jusqu’aux observations de la PZR géante et anomale dans le nano-silicium. Le chapitre 2 présente les modèles physiques de la PZR en régime ohmique. La théorie des SCLCs est ensuite introduite. Le chapitre 3 présente les dispositifs expérimentaux, les procédures de mesure ainsi que les échantillons étudiés. Le chapitre 4 contient les principaux résultats obtenus par la spectroscopie d’impédance. Une PZR géante et nouvel effet de piézo-capacitance sont observés. Une comparaison avec la théorie indique que les dispositifs opèrent dans une régime SCLC en présence de pièges électroniques rapides, et que la PZR géante résulte de la dépendance en contrainte des taux de capture et d’émission de ces pièges. Ceci donne lieu à des changements importants de densités de porteurs hors du régime stationnaire. Ce chapitre se termine sur une discussion, revisitée à la lumière de nos résultats, des effets controversés de PZR géante publiés dans la littérature. Le chapitre 5 traite la mesure de la dépendance en contrainte du « pinning » du niveau de Fermi de surface, réalisée en combinant cartographie Raman et photoémission sur des leviers en silicium statiquement fléchis dont les surfaces sont terminées par une oxyde native. L’observation d’un déplacement du niveau de Fermi de surface pair en contrainte tend à montrer que les défauts intrinsèques de surface (type Pb0) sont à l’origine des effets géants présentés dans le chapitre 4.Le chapitre 6 aborde les mesures en régime stationnaire de PZR du silicium n.i.d. de type n pour laquelle une densité de bi-lacunes de silicium a été introduite. La caractéristique courant-tension montre trois régimes : à basse tension une loi ohmique dominé par les électrons majoritaires ; à des tensions intermédiaires une loi de Mott-Gurney modifiée des trous injectés depuis les contacts p++ ; à haute tension un régime plasma électron-trou. La PZR est déterminée par le porteur majoritaire. A basse tension un comportement du silicium type n est observé (i.e. de signe négatif) tandis qu’aux tensions intermédiaires une PZR similaire à celle du silicium type p est observée (i.e. de signe positive). A haute tension la PZR correspond à la somme de ces, conséquence directe de la présence d’électrons et de trous dans le régime plasma. Le chapitre 7, tout en résumant les conclusions principales de cette thèse développe également les directions futures à explorer
This thesis presents a study of giant, anomalous piezo-resistance (PZR) in depleted nano-silicon. PZR in bulk silicon is a technologically important phenomenon in which mechanical stress changes the electrical resistivity via a change in the charge carrier effective masses. With continued reductions in device dimensions, it is of interest to explore the PZR of silicon micro- and nano-objects in which giant PZR and PZR of anomalous sign have been reported in recent years. The physical origin of these effects remains unclear and in some cases, even the veracity of the claimed results has been questioned. Some basic elements of the claimed effects are agreed upon, for example they occur in surface depleted nanostructures where transport is described by space charge limited currents (SCLC). In this thesis the details of the stress-dependence of the charge trapping and emission rates at fast electronic traps during SCLC transport in fully depleted silicon-on-insulator is probed using impedance spectroscopy. This, combined with an X-ray photo-electron spectroscopy study of statically deflected silicon cantilevers, strongly suggests that giant, non-steady-state PZR is due to stress-induced changes to hole trapping dynamics at intrinsic interface states. In contrast, under steady-state conditions like those used in all previous studies, giant PZR is not observed even in the presence of interface traps. On the other hand, anomalous, steady-state PZR is observed in defect engineered SCLC devices, and is shown to be the result of a voltage bias induced type change of the majority carrier. In chapter 1 the history of PZR is introduced. Prior reports of giant and anomalous PZR are then discussed. Chapter 2 presents the physical description of the PZR in silicon when transport occurs in the Ohmic regime. Both large-signal and small-signal SCLC transport are then introduced. Chapter 3 introduces the experimental details and the samples used throughout this work. Chapter 4 contains the principal impedance spectroscopy results. Giant, anomalous PZR and a novel piezo-capacitance are observed under non-steady-state conditions in fully-depleted silicon-on-insulator. Comparison of theory and data indicate that the devices operate in the SCLC regime in the presence of fast traps, and that the giant, anomalous PZR results from the stress dependence of the charge capture and emission rates of these traps. This in turn yields large changes of the non-equilibrium charge carrier concentrations. The importance of these observations in clarifying the physical origin, and the veracity of previous reports of steady-state, giant PZR, is discussed. Chapter 5 reports a comparison of Raman and XPS maps on statically deflected silicon cantilevers, providing a spectroscopic measurement of the stress-dependence of the pinned surface Fermi level at natively oxidized (001) silicon surfaces. A simplified analysis of the observed even symmetry of the stress-induced Fermi level shifts suggests that intrinsic interface defects (Pb0) are likely responsible for the giant, anomalous PZR reported in Chapter 4. Chapter 6 reports the DC bias dependence of the PZR in n.i.d. n-type, defect engineered silicon devices. The device characteristic exhibits three regimes; an Ohmic regime at low biases dominated by equilibrium electrons, a modified Mott-Gurney regime at intermediate biases dominated by holes injected from p++ contacts, and an electron-hole plasma regime at high biases. In each case the PZR depends on the majority carrier type; at low biases the usual n-type PZR is observed (i.e. the sign is negative); at intermediate biases it switches to the bulk p-type (i.e. positive) PZR; in the plasma regime, the PZR is a combination of the bulk electron and hole values. The results help shed light on observations of anomalous (i.e. sign reversed) PZR in depleted nano-silicon. Finally, chapter 7 summarizes the conclusions and introduces possible future research directions

Recall that a Banach space X has the Dunford-Pettis property if every weakly compact operator defined on X takes weakly compact sets into norm compact sets. Some valuable characterisations of Banach spaces with the Dunford-Pettis property are: X has the DPP if and only if for all Banach spaces Y, every weakly compact operator from X to Y sends weakly convergent sequences onto norm convergent sequences (i.e. it requires that weakly compact operators on X are completely continuous) and this is equivalent to “if (xn) and (x*n) are sequences in X and X* respectively and limn xn = 0 weakly and limn x*n = 0 weakly then limn x*n xn = 0". A striking application of the Dunford-Pettis property (as was observed by Grothendieck) is to prove that if X is a linear subspace of L() for some finite measure  and X is closed in some Lp() for 1 ≤ p < , then X is finite dimensional. The fact that the well known spaces L1() and C() have this property (as was proved by Dunford and Pettis) was a remarkable achievement in the early history of Banach spaces and was motivated by the study of integral equations and the hope to develop an understanding of linear operators on Lp() for p ≥ 1. In fact, it played an important role in proving that for each weakly compact operator T : L1()  L1() or T : C()  C(), the operator T2 is compact, a fact which is important from the point of view that there is a nice spectral theory for compact operators and operators whose squares are compact. There is an extensive literature involving the Dunford-Pettis property. Almost all the articles and books in our list of references contain some information about this property, but there are plenty more that could have been listed. The reader is for instance referred to [4], [5], [7], [8], [10], [17] and [24] for information on the role of the DPP in different areas of Banach space theory. In this dissertation, however, we are motivated by the two papers [7] and [8] to study alternative Dunford-Pettis properties, to introduce a scale of (new) alternative Dunford-Pettis properties, which we call DP*-properties of order p (briefly denoted by DP*P), and to consider characterisations of Banach spaces with these properties as well as applications thereof to polynomials and holomorphic functions on Banach spaces. In the paper [8] the class Cp(X, Y) of p-convergent operators from a Banach space X to a Banach space Y is introduced. Replacing the requirement that weakly compact operators on X should be completely continuous in the case of the DPP for X (as is mentioned above) by “weakly compact operators on X should be p-convergent", an alternative Dunford-Pettis property (called the Dunford-Pettis property of order p) is introduced. More precisely, if 1 ≤ p ≤ , a Banach space X is said to have DPPp if the inclusion W(X, Y)  Cp(X, Y) holds for all Banach spaces Y . Here W(X, Y) denotes the family of all weakly compact operators from X to Y. We now have a scale of “Dunford-Pettis like properties" in the sense that all Banach spaces have the DPP1, if p < q, then each Banach space with the DPPq also has the DPPp and the strongest property, namely the DPP1 coincides with the DPP. In the paper [7] the authors study a property on Banach spaces (called the DP*-property, or briey the DP*P) which is stronger than the DPP, in the sense that if a Banach space has this property then it also has DPP. We say X has the DP*P, when all weakly compact sets in X are limited, i.e. each sequence (x*n)  X * in the dual space of X which converges weak* to 0, also converges uniformly (to 0) on all weakly compact sets in X. It turns out that this property is equivalent to another property on Banach spaces which is introduced in [17] (and which is called the *-Dunford-Pettis property) as follows: We say a Banach space X has the *-Dunford-Pettis property if for all weakly null sequences (xn) in X and all weak* null sequences (x*n) in X*, we have x*n(xn) n 0. After a thorough study of the DP*P, including characterisations and examples of Banach spaces with the DP*P, the authors in [7] consider some applications to polynomials and analytic functions on Banach spaces. Following an extensive literature study and in depth research into the techniques of proof relevant to this research field, we are able to present a thorough discussion of the results in [7] and [8] as well as some selected (relevant) results from other papers (for instance, [2] and [17]). This we do in Chapter 2 of the dissertation. The starting point (in Section 2.1 of Chapter 2) is the introduction of the so called p-convergent operators, being those bounded linear operators T : X  Y which transform weakly p-summable sequences into norm-null sequences, as well as the so called weakly p-convergent sequences in Banach spaces, being those sequences (xn) in a Banach space X for which there exists an x  X such that the sequence (xn - x) is weakly p-summable. Using these concepts, we state and prove an important characterisation (from the paper [8]) of Banach spaces with DPPp. In Section 2.2 (of Chapter 2) we continue to report on the results of the paper [7], where the DP*P on Banach spaces is introduced. We focus on the characterisation of Banach spaces with DP*P, obtaining among others that a Banach space X has DP*P if and only if for all weakly null sequences (xn) in X and all weak* null sequences (x*n) in X*, we have x*n(xn) n 0. An important characterisation of the DP*P considered in this section is the fact that X has DP*P if and only if every T  L(X, c0) is completely continuous. This result proves to be of fundamental importance in the study of the DP*P and its application to results on polynomials and holomorphic functions on Banach spaces. To be able to report on the applications of the DP*P in the context of homogeneous polynomials and analytic functions on Banach spaces, we embark on a study of “Complex Analysis in Banach spaces" (mostly with the focus on homogeneous polynomials and analytic functions on Banach spaces). This we do in Chapter 3; the content of the chapter is mostly based on work in the books [23] and [14], but also on the work in some articles such as [15]. After we have discussed the relevant theory of complex analysis in Banach spaces in Chapter 3, we devote Chapter 4 to considering properties of polynomials and analytic functions on Banach spaces with DP*P. The discussion in Chapter 4 is based on the applications of DP*P in the paper [7]. Finally, in Chapter 5 of the dissertation, we contribute to the study of “Dunford-Pettis like properties" by introducing the Banach space property “DP*P of order p", or briefly the DP*Pp for Banach spaces. Using the concept “weakly p-convergent sequence in Banach spaces" as is defined in [8], we define weakly-p-compact sets in Banach spaces. Then a Banach space X is said to have the DP*-property of order p (for 1 ≤ p ≤ ) if all weakly-p-compact sets in X are limited. In short, we say X has DP*Pp. As in [8] (where the DPPp is introduced), we now have a scale of DP*P-like properties, in the sense that all Banach spaces have DP*P1 and if p < q and X has DP*Pq then it has DP*Pp. The strongest property DP*P coincides with DP*P. We prove characterisations of Banach spaces with DP*Pp, discuss some examples and then consider applications to polynomials and analytic functions on Banach spaces. Our results and techniques in this chapter depend very much on the results obtained in the previous three chapters, but now we have to find our own correct definitions and formulations of results within this new context. We do this with some success in Sections 5.1 and 5.2 of Chapter 5. Chapter 1 of this dissertation provides a wide range of concepts and results in Banach spaces and the theory of vector sequence spaces (some of them very deep results from books listed in the bibliography). These results are mostly well known, but they are scattered in the literature - they are discussed in Chapter 1 (some with proof, others without proof, depending on the importance of the arguments in the proofs for later use and depending on the detail with which the results are discussed elsewhere in the literature) with the intention to provide an exposition which is mostly self contained and which will be comfortably accessible for graduate students. The dissertation reflects the outcome of our investigation in which we set ourselves the following goals: 1. Obtain a thorough understanding of the Dunford-Pettis property and some related (both weaker and stronger) properties that have been studied in the literature. 2. Focusing on the work in the paper [8], understand the role played in the study of difierent classes of operators by a scale of properties on Banach spaces, called the DPPp, which are weaker than the DP-property and which are introduced in [8] by using the weakly p-summable sequences in X and weakly null sequences in X*. 3. Focusing on the work in the paper [7], investigate the DP*P for Banach spaces, which is the exact property to answer a question of Pelczynsky's regarding when every symmetric bilinear separately compact map X x X  c0 is completely continuous. 4. Based on the ideas intertwined in the work of the paper [8] in the study of a scale of DP-properties and the work in the paper [7], introduce the DP*Pp on Banach spaces and investigate their applications to spaces of operators and in the theory of polynomials and analytic mappings on Banach spaces. Thereby, not only extending the results in [7] to a larger family of Banach spaces, but also to find an answer to the question: “When will every symmetric bilinear separately compact map X x X  c0 be p-convergent?"
Thesis (M.Sc. (Mathematics))--North-West University, Potchefstroom Campus, 2012.

Yu Wai Ching.
"Architecture Department, Chinese University of Hong Kong, Master of Architecture Programme 2007-2008, design report."
Includes bibliographical references (p. 204-206).
Thesis Statement --- p.5
Study Method --- p.9
"Phenomenon, Principle & Appearance" --- p.11
Study Area --- p.15
Precedent study --- p.17
Chapter - --- Chinese character --- p.19
Chapter - --- Platonic solid --- p.35
Chapter - --- Crystal --- p.43
Architectural example study --- p.59
Chapter - --- Phenomenon - simple but interesting subdivision --- p.61
Chapter - --- Principle - subdivision --- p.71
Chapter - --- envelope arrangment --- p.115
Chapter - --- opening --- p.127
Chapter - --- space extension --- p.135
Chapter - --- Reading examples with principles --- p.145
Testing on site --- p.155
Site context --- p.157
Site planning --- p.163
Testing on village houses --- p.177
Housing types --- p.179
Floor units --- p.183
House unit --- p.189
Bibliography --- p.203

碩士
國立交通大學
光電工程系所
97
In this study, we developed a new vertical transistor and called space-charge limited transistors. Firstly, we discussed the pentacene carrier mobility in the vertical structure. The gold surface is modified by exposed ultraviolet light for several mins. According to our observation, after UV-treated gold surface, the work function of gold surface will be increased, the surface energy will be increased, and pentacene mobility will be improved, too. We used atomic force microscope to observe the pentacene molecular on gold with or without the UV treatment. In addition, we also observed the influence of pentacene deposition rate and mobility by used X-ray Diffractometer and atomic force microscope. Then, we demonstrated that the carrier will influence the bandwidth of frequency response. We used the polystyrene spheres as nano-scale mask to produce a mesh of the electrode structure, and we used the best previous results of pentacene evaporation to fabricate the space charge limited transistor. Therefore, we got a one volt operation voltage. However, we found some issues, such as the shadow effect of polystyrene spheres mask, the impact by nonuniform distribution of spheres, and the crystallization of active layer material itself so that the electrode spacing will be too close by using atomic force microscope and scanning electron microscope.

碩士
國立交通大學
光電工程研究所
103
The organic transistor has become more and more popular in recent years due to its advantages such as lower cost, simplicity in process, flexibility and high uniformity in large area which can hardly be found in the silicon transistor. This thesis will restrict transistors (space-charge-limited transistor, SCLT) components for small molecule material on the electrical properties of structures for Discussion. In the past we often used a conjugated polymer material poly (3-hexylthiophene), P3HT as an active layer material element, but the P3HT will react with the Oxygen in the air, resulting in deterioration of the electrical characteristics of components, as well as carrier mobility is not high. So we find some small molecules like HAT7 and TIPS pentacene to replace P3HT. Since HAT7 for the more novelty material, so this thesis only some discussion of basic electrical characteristics, but also has a structure in SCLT on/off ratio of 1000 to 10000. It is a good result on this basic research. On the other hand, from the recent studies have shown that TIPS pentacene can use different deposition methods, so that there is a small molecule arrangement direction of crystallization, and to obtain a high carrier mobility. Another advantage is able to stable in the air leading to most organic material, so we chose TIPs pentacene active layer material as a component. We use several thermal annealing conditions to make SCLT having current on/off ratio over 100000 and high output current over 20. To make the flexible device without package, we focused on TIPS pentacene SCLT for atmospheric stability made a series of tests.