VictorJuiz/thesis huggingface dataset:
Physical Synthesis Toolkit for Area and Power Optimization on FPGAs
Keywords: Area and Power Optimization Algorithms
Physical Synthesis
Power Modeling
Field-Programmable Gate Arrays

A Field-Programmable Gate Array (FPGA) is a configurable platform for implementing a variety of logic circuits. It implements a circuit by the means of logic elements, usually Lookup Tables, connected by a programmable routing network. To utilize an FPGA effectively Computer Aided Design (CAD) tools have been developed. These tools implement circuits by using a traditional CAD flow, where the circuit is analyzed, synthesized, technology mapped, and finally placed and routed on the FPGA fabric. This flow, while generally effective, can produce sub-optimal results because once a stage of the flow is completed it is not revisited. This problem is addressed by an enhanced flow known Physical Synthesis, which consists of a set of iterations of the traditional flow with one key difference: the result of each iteration directly affects the result of the following iteration. An optimization can therefore be evaluated and then adjusted as needed in the following iterations, resulting in an overall better implementation. This CAD flow is challenging to work with because for a given FPGA researchers require access to each stage of the flow in an iterative fashion. This is particularly challenging when targeting modern commercial FPGAs, which are far more complex than a simple Lookup Table and Flip-Flop model generally used by the academic community. This dissertation describes a unified framework, called the Physical Synthesis Toolkit (PST), for research and development of optimizations for modern FPGA devices. PST provides access to modern FPGA devices and CAD tool flow to facilitate research. At the same time the amount of effort required to adapt the framework to a new FPGA device is kept to a minimum. To demonstrate that PST is an effective research platform, this dissertation describes optimization and modeling techniques that were implemented inside of it. The optimizations include: an area reduction technique for XOR-based logic circuits implemented on a 4-LUT based FPGA (25.3% area reduction), and a dynamic power reduction technique that reduces glitches in a circuit implemented on an Altera Stratix II FPGA (7% dynamic power reduction). The modeling technique is a novel toggle rate estimation approach based on the XOR-based decomposition, which reduces the estimate error by 37% as compared to the latest release of the Altera Quartus II CAD tool.
Colloidal Quantum Dot Schottky Barrier Photodetectors
Keywords: nanotechnology
Schottky barrier
nanocrystal
colloidal quantum dot
solution processed semiconductor
optoelectronic
photovoltaic
photodetector

Herein, we report the first solution-processed broadband photodetectors to break the past compromise between sensitivity and speed of response. Specifically, we report photodiodes having normalized detectivity (D*) > 1012 Jones and a 3dB bandwidth of > 2.9 MHz. This finding represents a 170,000 fold improvement in response speed over the most sensitive colloidal quantum dot (CQD) photodetector reported1 and a 100,000 fold improvement in sensitivity over the fastest CQD photodetector reported2. At the outset of this study, sensitive, solution-processed IR photodetectors were severely limited by low response speeds1. Much faster response speeds had been demonstrated by solution-processed photodetectors operating in the visible3, but these devices offered no benefits for extending the spectral sensitivity of silicon. No available solution-processed photodetector combined high sensitivity, high operating speed, and response to illumination across the UV, visible and IR. We developed a fast, sensitive, solution-processed photodetector based on a photodiode formed by a Schottky barrier to a CQD film. Previous attempts to form sensitive photodetectors based on CQD photodiodes had demonstrated low quantum efficiencies that limited sensitivity4,5. Efficient, sensitive semiconductor photodiodes are based on two fundamental characteristics: a large built-in potential that separates photogenerated charge carriers and minimizes internal noise generation, and high semiconductor conductivity for efficient collection of photogenerated charge. Schottky barriers to CQD films were developed to provide high, uniform built-in potentials. A multi-step CQD ligand exchange procedure was developed to allow deposition of tightly packed films of CQDs with high mobility and sufficiently well-passivated surfaces to form high-quality metallurgical junctions. The temporal response of the CQD photodiodes showed separate drift and diffusion components. Combined with detailed measurements of the Schottky barrier, these characteristics provided the physical basis for a numerical model of device operation. Based on this understanding, devices that excluded the slow diffusive component were fabricated, exploiting only the sub-microsecond field-driven transient to achieve MHz response bandwidth. These devices are the first to combine megahertz-bandwidth, high sensitivity, and spectral-tunability in photodetectors based on semiconducting CQDs. Record performance is achieved through advances in materials and device architecture based on a detailed understanding the physical mechanisms underlying the operation of CQD photodiodes.
Wireless Communication over Fading Channels with Imperfect Channel Estimates
Keywords: Wireless communication
Fading channels
Diversity combining
Channel estimation error

In wireless communication systems, transmitted signals are corrupted by fading as well as noise. The receiver can benefit from the estimates of fading channels to detect the transmitted symbols. However, in practical wireless systems channel information cannot be estimated perfectly at the receiver. Therefore, it is crucial to examine the effect of channel estimation error on the structure and performance of the receivers. In the first part of the thesis, we study single-user systems with single-antenna reception over fading channels in the presence of Gaussian-distributed channel estimation error. By using the statistical information of the channel estimation error, we will derive the structure of maximum-likelihood receivers for a number of different modulation formats and then analyze their performance over fading channels. In the second part of the thesis, we consider the uplink of multi-user wireless systems with multi-antenna reception. For conventional diversity combining techniques such as maximal ratio combining and optimum combining we analyze the performance degradation due to imperfect channel estimates in the presence of multiple interfering users for several fading channels. By investigating the probability density function of the output signal-to-interference ratio, we will derive analytical expressions for several performance measures such as the average signal-to-interference ratio, outage probability and average bit-error probability. These expressions quantify performance degradation due to channel estimation error.
Cultural Expressions of Tokugawa Japan and Chosŏn Korea: an Analysis of the Korean Embassies in the Eighteenth Century
Keywords: Japan-Korea relations
the 18th century

This doctoral thesis presents a historical study of the diplomatic exchanges between the Japanese and the Korean embassy in the eighteenth century. Neighbourly relationships (J: kōrin, K: kyorin) were maintained between Tokugawa Japan (1603-1868) and Chosŏn Korea (1392-1910) for more than 250 years. The visitations of the Korean embassy, dispatched to congratulate a new Tokugawa shogun, were often seen as the symbol of their amicable and friendly relationship, and it is well known that the Koreans were cordially welcomed by the Tokugawa bakufu. Despite these neighbourly relations, the visitations of the embassy had a more pragmatic purpose. More complex political conditions and nature were immanent within and between the both states. In the diplomatic interaction, the officials in the two states had traditional and obstinately-held perceptions towards the counterpart hidden behind the pleasant gesture. In this thesis, I attempt to uncover what is associated with these neighbourly relations, by revealing the cultural awareness and consciousness of these two states in East Asia through detailed examinations of the historical sources. To find the notions behind the exchange, my thesis illustrates Japanese and Korean hua-yi awareness that came to light through the interactions between the Japanese and the Koreans. The Chinese hua-yi order, the concept of looking at the Chinese dynasties as the center, was said to dominate the East Asian order. From the Chinese point of view, Tokugawa Japan and Chosŏn Korea were barbaric and on the margins, but from the perspectives of the two countries, they certainly recognized themselves as the centers. On the basis of the dynamism of historical events, thoughts, and notions between Tokugawa Japan and Chosŏn Korea in the eighteenth century, this research will examine multi-layered perspectives of the individual Japanese and Koreans who played essential roles in diplomacy. How were those officials representing the two states aware of their peers, and how did these notions affect the modern history of the two countries? This question is consistently engaged in this thesis, and to answer it the research will be further explored.
Migrant and Border Subjects in Late Choson Korea
Keywords: Korea
Choson
Neo-Confucianism
Ming
Jurchen
Migration
Lineage
Ritual
Qing
Manchu

This thesis explores the changing approach of the Chosŏn state to subjects with foreign lineages in the period between the Imjin War (1592-98) and the early nineteenth century. Chosŏn Korea underwent considerable upheaval during the Imjin War and the wars of the Ming-Qing transition. Many Jurchen subjects of the Chosŏn court were forced from their homes in the Tumen Valley into the banner armies of the rising Qing state, with only a remnant persisting in Chosŏn. Additionally, large numbers of Ming Chinese entered Chosŏn either with the Ming army or as refugees from war in Liaodong. Initially, the Chosŏn state responded to its Jurchen and Ming Chinese subjects primarily through pragmatic concern about the loyalty of these subjects to the Chosŏn and the burden they imposed on the agricultural economy. As a result, the Chosŏn court welcomed and even defended the Jurchen as established Chosŏn subjects but was cautious of the more alien Ming deserters and refugees. Ming migrant status did not improve during the remainder of the seventeenth century. Ming Chinese lineages were considered, along with Jurchen and Japanese, within the same invidious submitting foreigner tax category. During the same period fraudulent Ming migrants became a focus for sedition among non-elites. The eighteenth century rise of Ming Loyalist ritualism transformed the response of the Chosŏn court to such foreign lineages as Ming migrant lineages were encouraged to participate in court-sponsored Ming loyalist rituals. Along with this ritual participation Ming migrant status was transformed from that of submitting foreigners to that of imperial subjects, while Jurchen and Japanese lineages disappeared. At the same time, hagiographic biographies were written of the original Ming Chinese refugees which praised them for coming to Chosŏn because of Neo-Confucian loyalty to the Ming. The Chosŏn state responded to foreign lineages according to changing circumstances. Neo-Confucian ritualism only played a role in response to Ming lineages in the eighteenth century when earlier concerns about disloyalty and social disruption had largely passed.
Neural Mechanisms of Temporomandibular Joint and Masticatory Muscle Pain
Keywords: excitatory amino acid
TRPV1
glutamate
capsaicin
incision
trigeminal
pre-emptive analgesia

The underlying nociceptive mechanisms in temporomandibular joint (TMJ) and masticatory muscles in many pain conditions are still unclear, largely due to the limited study of peripheral and central neural mechanisms affecting craniofacial musculoskeletal tissues. This study provided evidence in support of Hypothesis 1: Peripheral glutamatergic and capsaicin-sensitive mechanisms modulate the properties of primary afferents and brainstem neurons processing deep craniofacial nociceptive information. Effects of glutamate and capsaicin injected into the receptive field of deep craniofacial nociceptive afferents or TMJ of TMJ-responsive nociceptive neurons in trigeminal subnucleus caudalis/upper cervical cord (Vc/UCC) were studied in halothane-anesthetized rats. When injected alone, glutamate and capsaicin activated and induced peripheral sensitization in many afferents. Following glutamate injection, capsaicin-evoked activity was greater than that evoked by capsaicin alone, whereas following capsaicin injection, glutamate-evoked responses were similar to those of glutamate alone. When injected alone, glutamate and capsaicin also activated and induced central sensitization in most Vc/UCC neurons. Following glutamate injection, capsaicin evoked greater activity and less sensitization compared with capsaicin alone, whereas following capsaicin, glutamate was less effective in activating and sensitizing most Vc/UCC neurons. This apparent desensitizing effect of capsaicin on glutamate-evoked excitability of Vc/UCC neurons contrasts with the lack of capsaicin-induced modulation of glutamate-evoked afferent excitability, suggesting that peripheral and central sensitization may be differentially involved in the nociceptive effects of glutamate and capsaicin applied to deep craniofacial tissues. Further evidence of glutamate-capsaicin interactions was documented in the attenuation by TMJ pre-injection of glutamate receptor antagonists of jaw muscle activity reflexly evoked by TMJ injection of capsaicin. Moreover, additional findings support Hypothesis 2: Surgical cutaneous incision modulates the properties of brainstem neurons processing deep craniofacial nociceptive information. TMJ-responsive nociceptive Vc/UCC neurons could be activated by surgical incision of the skin overlying the TMJ and this incision-induced afferent barrage caused nociceptive neurons to be temporarily refractory to further capsaicin-induced central sensitization. These novel findings suggest that peripheral glutamate and capsaicin receptor mechanisms as well as surgical cutaneous incision may be involved in the nociceptive processing of deep craniofacial afferent inputs and may interact to modulate both activation as well as sensitization evoked from these tissues.
Behavioural Model Fusion
Keywords: Model Merging
Model Composition
Model Management
Behavioural Models
Refinement
Temporal Logic
Bisimulation/Simulation
State Machine

In large-scale model-based development, developers periodically need to combine collections of interrelated models. These models may capture different features of a system, describe alternative perspectives on a single feature, or express ways in which different features alter one another's structure or behaviour. We refer to the process of combining a set of interrelated models as "model fusion". A number of factors make model fusion complicated. Models may overlap, in that they refer to the same concepts, but these concepts may be presented differently in each model, and the models may contradict one another. Models may describe independent system components, but the components may interact, potentially causing undesirable side effects. Finally, models may cross-cut, modifying one another in ways that violate their syntactic or semantic properties. In this thesis, we study three instances of the fusion problem for "behavioural models", motivated by real-world applications. The first problem is combining "partial" models of a single feature with the goal of creating a more complete description of that feature. The second problem is maintenance of "variant" specifications of individual features. The goal here is to combine the variants while preserving their points of difference (i.e., variabilities). The third problem is analysis of interactions between models describing "different" features. Specifically, given a set of features, the goal is to construct a composition such that undesirable interactions are absent. We provide an automated tool-supported solution to each of these problems and evaluate our solutions. The main novelties of the techniques presented in this thesis are (1) preservation of semantics during the fusion process, and (2) applicability to large and evolving collections of models. These are made possible by explicit modelling of partiality, variability and regularity in behavioural models, and providing semantic-preserving notions for relating these models.
Interactive Content Adaptation
Keywords: Content Adaptation
Mobile Devices
Web
Customization
Context
Systems

Mobile devices are increasingly being used to access Web content but lack the resources for proper presentation to the user. To address this problem, content is typically customized to be more suitable for a mobile environment. Automatic customization of web content is a challenging problem because fine-grain adaptation often depends on both the relevance of individual objects on a web page, as well as the context of access (e.g., screen size of device being used, network connectivity, location, etc.). We present Usage-aware Interactive Content Adaptation, an adaptation technique that allows a user who is unsatisfied with the system’s adaptation decision to take control of the adaptation process and make changes until the content is suitably adapted for her purposes. The adaptation system learns from the user’s modifications and adjusts its prediction for future accesses by other users. With this approach, users are empowered to correct bad adaptation decisions made by the system without being overly burdened. We applied the technique in two domains: adapting the quality of images to reduce download times and save energy and bandwidth, and customizing the layout of images to improve the utilization of screen real-estate. The work was evaluated through a series of user studies, and the results show that user feedback can be effectively used to provide appropriate customizations (i) for objects with varying relevance, (ii) when context affects the users adaptation requirements, and (iii) when the same content can be used for multiple purposes by different users.
Acquiring and Reasoning about Variability in Goal Models
Keywords: Software Engineering
Requirements Engineering

One of the most essential parts of any software requirements analysis effort is the exploration of alternative ways by which stakeholder problems can be solved. Systematic modeling and analysis of requirements variability allows better decision making during the early requirements phase and substantiates design choices pertaining to the configurability aspect of the system-to-be. This thesis proposes the use of goal models for capturing and reasoning about requirements variability. The goal models we adopt consist of AND/OR decompositions of stakeholder goals and express alternative ways by which stakeholders may wish to achieve them. By capturing goal variability using such models, we propose a shift of focus from variability of the software design, to variability of the problem that the design is intended to solve. This way, we ensure that every important variation of the problem is identified and analyzed before variations of the solution are specified. The thesis exploits opportunities that arise from this new viewpoint. Firstly, a variability-intensive goal decomposition process is proposed. The process is based on associating each high-level goal to a set of variability concerns that must be addressed through decomposition. We introduce a universal categorization of such concerns and also show how domain-specific variability concerns can be identified by annotating domain corpora. Concern-driven decomposition offers a structured way of thinking about problem variability, while systematizing its identification process. Further, an expressive LTL-based preference language is introduced to support leverage of large spaces of goal alternatives. The language allows the expression of preferences over behavioral and qualitative properties of solutions and a reasoning tool allows the identification of alternatives that satisfy these preferences. This way, individual stakeholders can get the solution that exactly fits their needs in a particular situation, through simply specifying desired high-level characteristics of these solutions. Finally, a framework for connecting alternatives at the goal level to alternative configurations of common desktop applications is presented. The framework shows how a vast number of configurations of a software application can be evaluated and ranked with respect to a small number of quality goals that are more intuitive to and comprehensible by end users.
Nogood Processing in CSPs
Keywords: Computer Science
Constraint Satisfaction
Propositional Satisfiability

The constraint satisfaction problem is an NP-complete problem that provides a convenient framework for expressing many computationally hard problems. In addition, domain knowledge can be efficiently integrated into CSPs, providing a potentially exponential speedup in some cases. The CSP is closely related to the satisfiability problem and many of the techniques developed for one have been transferred to the other. However, the recent dramatic improvements in SAT solvers that result from learning clauses during search have not been transferred successfully to CSP solvers. In this thesis we propose that this failure is due to a fundamental restriction of \newtext{nogood learning, which is intended to be the analogous to clause learning in CSPs}. This restriction means that nogood learning can exhibit a superpolynomial slowdown compared to clause learning in some cases. We show that the restriction can be lifted, delivering promising results. Integration of nogood learning in a CSP solver, however, presents an additional challenge, as a large body of domain knowledge is typically encoded in the form of domain specific propagation algorithms called global constraints. Global constraints often completely eliminate the advantages of nogood learning. We demonstrate generic methods that partially alleviate the problem irrespective of the type of global constraint. We also show that more efficient methods can be integrated into specific global constraints and demonstrate the feasibility of this approach on several widely used global constraints.