Miracle-dz/UniFAR-FTUs huggingface dataset:
Heurísticas para o problema de caminho mais curto robusto

O problema de caminho mais curto (SP, do ingles Shortest Path) consiste em encontrar o caminho mais curto partindo de um vertice de origem $s \in V$ ate um vertice de destino $t \in V$ onde o custo total do caminho e minimo. Porem, diversas aplicacoes para o SP dependem de dados que nao sao fixos. O Problema do Caminho Mais Curto Robusto (RSP, do ingles Robust Shortest Path) generaliza o SP de forma que os dados incertos podem ser modelados como um intervalo ou como um conjunto de cenarios discretos. Este trabalho foca no criterio de otimizacao robusta minmax com arrependimento relativo utilizado a modelagem por intervalo para as incertezas. Foram desenvolvidas diversas heuristicas com enfase no fornecimento de metodos eficientes e escalaveis para resolver o minmax RSP Intervalar com arrependimento relativo, como heuristicas construtivas, heuristicas baseadas em pilot method, e um algoritmo genetico de chaves aleatorias.
Methods of Reverse Engineering a Bitstream for Field Programmable Gate Array Protection

Field Programmable Gate Arrays (FPGAs) are found in numerous industries including consumer electronics, automotive, military and aerospace, and critical infrastructure. The ability to be reprogrammed as well as large computational power and relatively low price make them a good fit for low-volume applications that cannot justify the Non-Recurring Engineering (NRE) costs associated with producing Application-Specific Integrated Circuits (ASICs). FPGAs however, have seen a variety of security issues stemming from the fact that their configuration files are not inherently protected. This research assesses the feasibility of reverse engineering the bitstream format for a previously unexplored FPGA, as well as the utilization of the knowledge gained during that process to create a bitstream parser and perform a bitstream modification attack. The reverse engineering process utilizes Tool Command Language (TCL) scripts to automate the modification of various configuration options and then synthesize the resulting bitstream. Various configuration options for Input/Output Blocks (IOBs) are mapped to their respective locations in the bitstream and the encoding format for the configuration of several Look-Up Tables (LUTs) is discovered. This information is then utilized to create a bitstream parser that takes a bitstream as an input and outputs configuration information for IOBs. Additionally, a bitstream modification attack is performed that changes the original design logic by modifiying the bitstream directly to change the configuration values of a LUT. Both the parser and bitstream modification attack are shown to work validating the information gained through the reverse engineering process.
Influence of contribution-based resource allocation mechanism on individual resource sharing cooperation in social networks

In social networks, resource sharing behaviors always take place in groups of individuals and rely on voluntary cooperation. In this work, first, a multi-player donor recipient game in which strategies describe individuals’ varying degrees of willingness to share resources is formulated, instead of using the limited binary decisions (e.g. share or not share) in a classical donor-recipient game. Second, the evolutionary dynamics of individual strategies are explored under the influence of two contribution-based resource allocation mechanisms: the total contribution-based allocation mechanism (TCAM) and the direct contribution-based allocation mechanism (DCAM). The results indicate that the network is dominated by the full-cooperation strategy when the cost-to-benefit ratio of resources is not too large and the DCAM is more effective than TCAM. Furthermore, the underlying reason why some strategies with higher sharing willingness can coexist in specific situations, is also explained in detail by leveraging macroscopic and microscopic perspective analysis. Finally, the influences of slandering and whitewashing behaviors conducted by a few malicious individuals on the allocation mechanisms are also studied. Current research will offer new insights into understanding the influence and optimizing the resource allocation policies in social networks.
On discontinuous differential equations

The paper studies and compare generalized solutions to discontinuous differential equations. This way, are studied and compared the Euler, Filippov, Hermes, Krasovskii, and Sentis generalized solutions to discontinuous differential equations. In particular, are studied relations between Euler and Hermes solutions. In addition, it is proved that Hermes solutions satisfy some properties that are analogous to the properties satisfied by Euler solutions.
Bancos e concentração de crédito no Brasil: 1995-2004

A partir da estabilizacao monetaria em 1994, houve uma aceleracao do processo de consolidacao bancaria no Brasil. Este movimento segue tendencia mundial de concentracao, na medida em que o segmento e desregulamentado. O presente trabalho analisa o efeito da concentracao bancaria quanto a concessao de credito, no Brasil, no periodo de 1995 a 2004. Para isso, foi realizada estimacao em painel utilizando dados das vinte e sete unidades da federacao. Os resultados corroboram a ideia de que o processo de consolidacao do setor bancario brasileiro exerce impacto negativo sobre a concessao de credito e, assim, prejudica, principalmente, as regioes menos desenvolvidas do pais.
Tree Technology for Memory Confidentiality Integrity Protection

PCIPunderline{ }Tree is a Parallelized memory Confidentiality and Integrity Protection technology (PCIP) method that pre-diffuses and encrypts the data stored in off-chip counter value for confidentiality and integrity protection of data, adding redundant checking data to the protection data block to ensure the integrity and confidentiality of the memory data. Then use the Simple Scalar tool to run 10 processors (SPEC2000) benchmark programs to simulation test. The result shows that the PCIPunderline{ }Tree method is greatly improved the running efficiency and the efficiency of encryption methods to compare with the Parallelized Encryption and Integrity Checking Engine (PE-ICE) method, at the same time, through the redundant data to check data integrity is better than using complex Hash algorithm to calculate the checking value and reduce system delay, reduce storage overhead chip, and ensure the real-time encryption and checking.
Cicada-inspired self-cleaning superhydrophobic surfaces

Water-based heat transfer surfaces in HVAC&R (Heating, Ventilation, Air Conditioning and Refrigeration) systems have biofouling or microbial growth which might not only impose adverse effects to public health but also deteriorate the heat transfer performance of surfaces. In nature, a living creature is surviving while being exposed to formidable condition such as bacteria and fungi. Cicada wing has known to have multi-functional wings exhibiting nonwetting, and anti-microbial due to nanoscale pillars and biochemicals to achieve non-wetting characteristics. We conducted experiments on cicada wings and cicada-inspired engineered superhydrophobic samples to show that droplets jumping from superhydrophobic wings could carry away individual particles (~100 µm) or cluster of particles. This study was investigated on self-cleaning mechanism using jumping droplet condensation and elucidate further antifouling characteristics of non-wetting heat transfer surfaces.
Metodologias para validação de proteções de linhas de transmissão

Este trabalho tem como objetivo descrever a aplicacao atual de equipamentos de protecao e controle no sistema de transmissao e apresentar os recursos, metodologias e procedimentos que sao utilizados pelos especialistas em protecao para a realizacao de testes em sistemas de protecao de linhas de transmissao do Sistema Interligado Nacional (SIN), dotados de esquemas de teleprotecao, tanto durante o processo de comissionamento de novas instalacoes comonos processos de manutencao. Devido as suas caracteristicas, as metodologias apresentadas constituem-se hoje como a principal alternativa a fim de validar de forma plena os desempenhos operacionais dos sistemas de protecao, esquemas e equipamentos de teleprotecao associados, disjuntores, esquemas de religamento com verificacao de sincronismo e eventuais esquemas especiais de protecao que dependam do intercâmbio de informacoes entre os terminais envolvidos. Uma metodologia para validacao de equipamentos e esquemas de protecao e controle sera tambem apresentada usando simulacao em tempo real, com o objetivo de adequar- se a nova realidade imposta pela tecnologia digital e pelo aumento da complexidade dos sistemas eletricos de potencia.
Elastic properties and frequency performance of a novel 3–0-type three-component composite

Abstract A three-component 3–0-type composite based on the ferroelectric PZT-type ceramic is studied to show the elastic properties and their links to the piezoelectric properties and resonance frequencies. The corundum ceramic is used as a component with a large elastic stiffness, and in the presence of this component, almost equal volume fractions of corundum mc and air pores mp are achieved at 0.05 < mc < 0.18. This influences the elastic and other properties of the studied composite. Experimental results on its performance are interpreted in terms of a model wherein an interaction between the 3–0 ferroelectric ceramic/corundum and 3–0 ferroelectric ceramic/air regions plays the important role. A correlation between the elastic and piezoelectric anisotropy factors is observed, and the anisotropy of the piezoelectric coefficients / ≈ −4 is stated at mc > 0.10. The studied composite is of interest as an active element of piezoelectric transducers and sensors.
Simulation of blood flow past a distal arteriovenous-graft anastomosis at low Reynolds numbers

Patients with end-stage renal disease are usually treated by hemodialysis while waiting for a kidney transplant. A common device for vascular access is an arteriovenous graft (AVG). However, AVG failure induced by thrombosis has been plaguing dialysis practice for decades. Current studies indicate that the thrombosis is caused by intimal hyperplasia, which is triggered by the abnormal flows and forces [e.g., wall shear stress (WSS)] in the vein after AVG implant. Due to the high level of complexity, in almost all of the existing works of modeling and simulation of the blood-flow vessel-AVG system, the graft and blood vessel are assumed to be rigid and immobile. Very recently, we have found that the compliance of graft and vein can reduce flow disturbances and lower WSS [Z. Bai and L. Zhu, “Three-dimensional simulation of a viscous flow past a compliant model of arteriovenous-graft anastomosis,” Comput. Fluids 181, 403–415 (2019)]. In this paper, we apply the compliant model to investigate possible effects of several dimensionless parameters (AVG graft-vein diameter ratio Rgv, AVG attaching angle θ, flow Reynolds numbers Re, and native vein speed Vv) on the flow and force fields near the distal AVG anastomosis at low Reynolds numbers (up to several hundreds). Our computational results indicate that the influences of the parameters Rgv, θ, and Re lie largely on the graft and the influence of Vv lies largely on the vein. In any case, the WSS, wall shear stress gradient, and wall normal stress gradient and their averaged values on the graft are significantly greater than those on the vein.Patients with end-stage renal disease are usually treated by hemodialysis while waiting for a kidney transplant. A common device for vascular access is an arteriovenous graft (AVG). However, AVG failure induced by thrombosis has been plaguing dialysis practice for decades. Current studies indicate that the thrombosis is caused by intimal hyperplasia, which is triggered by the abnormal flows and forces [e.g., wall shear stress (WSS)] in the vein after AVG implant. Due to the high level of complexity, in almost all of the existing works of modeling and simulation of the blood-flow vessel-AVG system, the graft and blood vessel are assumed to be rigid and immobile. Very recently, we have found that the compliance of graft and vein can reduce flow disturbances and lower WSS [Z. Bai and L. Zhu, “Three-dimensional simulation of a viscous flow past a compliant model of arteriovenous-graft anastomosis,” Comput. Fluids 181, 403–415 (2019)]. In this paper, we apply the compliant model to investigate possible effects.
Simplified wide dynamic range CMOS image sensor with 3t APS reset-drain actuation

Um sensor de imagem e uma matriz de pequenas celulas fotossensiveis chamadas sensores de pixeis. Um pixel, elemento el fotografico (picture) pix, e a menor porcao de uma imagem. Assim o sensor de pixel e a menor celula de um sensor de imagem, capaz de detectar um ponto singular da imagem. Este ponto e entao usado para reconstruir um quadro completo de imagem. Sensores de imagem CMOS sao atualmente largamente utilizados tanto em câmeras profissionais como em aparelhos moveis em geral como celulares. Uma importante caracteristica de um bom sensor de imagem e a capacidade de acomodar na mesma imagem regioes de alta e baixa luminosidade, chamada de alcance dinâmico do sensor. Muitas tecnicas, encontradas na literatura, sao capazes de aumentar o alcance dinâmico do sensor, cada uma com vantagens e desvantagens, tanto retardando o nivel de saturacao quanto reduzindo o ruido base. Nao idealidades introduzidas durante o processo de fabricacao produzem artefatos indesejaveis na imagem conhecidos com ruido de padrao fixo (fixed-pattern noise) FPN e esta entre os principais contribuintes para a determinacao do ruido base em sensores de imagem CMOS. Reducao de FPN em sensores de imagem com largo alcance dinâmico ainda e um desafio, pois ao aplicar qualquer das tecnicas existentes, outras caracteristicas essenciais do sensor sao comprometidas, como velocidade de processamento, reducao de area fotossensivel, ou aumento de custo de fabricacao. Este trabalho tem por objetivo aprimorar a operacao de sensores de imagem CMOS, que operam com largo alcance dinâmico para aplicacoes praticas em geral, atraves da aplicacao de tecnicas simples de circuito, sem interferir no processo de fabricacao. Para isso e proposto uma maneira simples e inovadora de aumentar o alcance dinâmico da mais basica e popular arquitetura de sensor de pixel atualmente usada em tecnologias CMOS. A ideia proposta tem duas diferencas basicas do corrente estado-da-arte. A primeira e a capacidade de aumentar o alcance dinâmico sem elevar o nivel de tensao de qualquer sinal de controle acima do nivel da alimentacao. A segunda e a simplicidade da tecnica de reducao de FPN neste tipo de sensor em relacao as demais encontradas na literatura. Nas tecnicas, atualmente encontradas na literatura, a elevacao do nivel de tensao em alguns sinais de controle e necessaria para evitar arquiteturas mais complexas, que reduzem a area fotossensivel do sensor. Por outro lado a elevacao da tensao acima do nivel da alimentacao e prejudicial, pois reduz o tempo de vida util do sensor de imagem. A simplicidade da tecnica de reducao de FPN proposta neste trabalho e capaz de manter inalterada caracteristicas importantes do sensor, como aquelas citadas acima, sem custo de fabricacao adicional.
Analysis and experiments on transmission characteristics of LCCL mobile wireless power transfer system

Wireless power transfer (WPT) systems can be used in various situations such as electric vehicles and electronic equipments. This paper developed a mobile WPT system with a LCCL resonance structure and a parameter configuration method to develop favorable transmission characteristics. Using the circuit equivalence principle, the formula for output power and transmission efficiency of the system was obtained. The system parameters were determined and the transmission characteristics of the system were analyzed by simulation. The experimental platform was built according to the determined parameters and was used to analyze the transmission characteristics of the system. The experimental results show that the developed system can acquire favorable transmission characteristics and provide an effective means for 1.5 kW WPT application.
An End-to-End Calibration Method for Welding Robot Laser Vision Systems With Deep Reinforcement Learning

Structured light calibration and robot hand-eye calibration are two of the most crucial parts in welding robot laser vision systems. The main aspect of this calibration is accuracy. To reduce the impact of errors in the calibration process and improve the accuracy, an end-to-end calibration method for laser vision systems based on deep reinforcement learning is proposed. The proposed method involves two dual learning tasks: a pixel-to-point module and a point-to-wrist transformation. The pixel-to-point module predicts the locations of the feature points in the welding image, while the point-to-wrist transformation establishes an accurate conversion relationship from the pixel frame to the wrist frame of the robot. Point-to-wrist transformation consists of two major components: “actor” and “critic. ” The “actor” model aims to infer the coordinates of the feature points in the wrist frame of the robot. In offline training, the “critic” model is introduced to guide the learning process of the “actor” model by maintaining the geometric consistency between the image coordinate and the robot coordinate. According to experimental results from the welding robot with continuous motion and changing poses, the proposed method significantly reduces the impact of errors in the calibration process and establishes a more accurate conversion relationship.
A Clinical Trial Design With Covariate-Adjusted Response-Adaptive Randomization Using Superiority Confidence of Treatments

Abstract Adaptive randomization using response outcome or covariate is commonly used in the literature. However, the performance of these designs has not been thoroughly studied, especially when there are various interactions between the covariate and treatment. We have conducted simulations to evaluate the performance of commonly used designs under two-arm and multiple-arm situations. When a predictive factor exists, in the phase II trial conduction using adaptive designs, such as the BATTLE-1, BATTLE-2 trial, and ISPY-2 trials, researchers evaluate the operating characteristics using the traditional power assessment. In this article, new criteria are used in a general modeling frame work to incorporate the complicated interaction. Based on our evaluation, the covariate-adjusted and response-adaptive randomization (Sc-ca) results in a greater total number of responders. Additionally, the design can detect the treatment effect difference in subgroups, and consistently assign patients to the most beneficial treatment according to their covariate profiles. This translates into a higher proportion of individuals receiving optimized treatments compared with other commonly used designs. This adaptive design is a step toward personalized therapy to benefit each patient enrolled in a prospective clinical trial, when there is the strong evidence that predictive factors exist.
Numerical Methods for Elliptic Partial Differential Equations and Optimal Control Problems

This thesis studies numerical methods for elliptic partial differential equations and optimal control problems. Second order and fourth order elliptic equations arise in various applications, for example, image processing, thin plates and the Stokes problem in stream function vorticity formulation. The first part focuses on fourth order elliptic equations and a unified convergence analysis framework known as the Hessian discretisation method. The second part focuses on the numerical analysis for optimal control problems governed by second order and fourth order elliptic equations. The second order problems are first considered for which the corresponding framework is called the gradient discretisation method.
Performance Degradation Assessment for Electrical Machines Based on SOM and Hybrid DHMM

Aimed at the timely detection of the degradation of electrical machines and the organization of active maintenance, numerous studies on performance degradation assessment have been conducted. However, previous research still suffers from two deficiencies: 1) determining the relevant relationship among diverse machine degradation states and assessing the specific degree of deterioration and 2) determining the evolutionary relationships among degradation and failure modes and assessing the failure modes corresponding to different degradation scenarios. To address these two deficiencies, a novel performance degradation assessment method is proposed. First, the self-organizing feature map (SOM) network is used to mine the latent degradation states of electrical machines. Second, the latent states are quantified according to established statistical health indexes, and by analyzing the distribution of extracted health indexes corresponding to different degradation states, the relevant transition relationships of the valid degradation states and the final evolving fault types are determined. Third, a hybrid discrete HMM is developed to fully describe the transition process among different states and assess the degradation scenario of a machine in an online manner. The results of a real application of an electric point machine show that the proposed method can identify valid degradation states and obtain a superior assessment accuracy.
Computation of Lebesgue’s Space-Filling Curve

The means of realizing or approximating the Lebesgue space-filling curve (SFC) with binary arithmetic on a uniformly spaced binary grid are not obvious, one problem being its formulation in terms of ternary representations; that impediment can be overcome via use of a binary-oriented Cantor set. A second impediment, namely the Devil’s Staircase feature, also created by the role of the Cantor set, can be overcome via the definition of a “working inverse”, thereby providing means of achieving compatibility with such a grid. The results indicate an alternative way to proceed, in realizing an approximation to Lebesgue’s SFC, which circumvents any complication raised by Cantor sets and is compatible with binary and integer arithmetic. Well-known constructions such as the z-curve or Morton order, sometimes considered in association with Lebesgue’s SFC, are treated as irrelevant.
Analysis of Image Revival through Visual Attention & Saliency Ingredient

The express use of internet and multimedia technology, people regularly generate partial-duplicate images for sharing of picture, information delivery, and so on. Unlike in traditional image retrieval, the duplicate regions in partial same images are only parts of the whole images and the various kinds of Technique involve scale, viewpoint, Brightness, and resolution. Such technique makes the retrieval task more complicated and challenging. Nevertheless, partial duplicate image Revival is expecting by various real world applications (such as fake image detection, copy protection, and landmark search) and thus has Attention increasing research attention. In object based image retrieval methods usually use the Full image as the query. This technique has been in comparison with the text retrieval system by using the bag of visual words (BOV) [3]. There is Plenty of background noise in the images and impossible to perform interaction operation on the large scale Directory of the images. Two observations are makeable as a user point of view. First, people show various region through the images which are shared on the web, we also expect that the returned result also focus on the main parts. Regions of interest are only found in salient region of the retrieval. Second and the similar region in the returned result also same to the salient region of the images. To filter out the non-salient region from the image, which able to remove the background noise we introduce visual attention analysis technique. We also want to produce saliency region which Contain the expected visual contents.