826 resultados para Stack Overflow
Resumo:
Self-report underpins our understanding of falls among people with Parkinson’s (PwP) as they largely happen unwitnessed at home. In this qualitative study, we used an ethnographic approach to investigate which in-home sensors, in which locations, could gather useful data about fall risk. Over six weeks, we observed five independently mobile PwP at high risk of falling, at home. We made field notes about falls (prior events and concerns) and recorded movement with video, Kinect, and wearable sensors. The three women and two men (aged 71 to 79 years) having moderate or severe Parkinson’s were dependent on others and highly sedentary. We most commonly noted balance protection, loss, and restoration during chair transfers, walks across open spaces and through gaps, turns, steps up and down, and tasks in standing (all evident walking between chair and stairs, e.g.). Our unobtrusive sensors were acceptable to participants: they could detect instability during everyday activity at home and potentially guide intervention. Monitoring the route between chair and stairs is likely to give information without invading the privacy of people at high risk of falling, with very limited mobility, who spend most of the day in their sitting rooms.
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We focus this work on the theoretical investigation of the block-copolymer poly [oxyoctyleneoxy-(2,6-dimethoxy-1,4phenylene-1,2-ethinylene-phenanthrene-2,4diyl) named as LaPPS19, recently proposed for optoelectronic applications. We used for that a variety of methods, from molecular mechanics to quantum semiempirical techniques (AMI, ZINDO/S-CIS). Our results show that as expected isolated LaPPS19 chains present relevant electron localization over the phenanthrene group. We found, however, that LaPPS19 could assemble in a pi-stacked form, leading to impressive interchain interaction; the stacking induces electronic delocalization between neighbor chains and introduces new states below the phenanthrene-related absorption; these results allowed us to associate the red-shift of the absorption edge, seen in the experimental results, to spontaneous pi-stack aggregation of the chains. (C) 2009 Wiley Periodicals, Inc. Int J Quantum Chem 110: 885-892, 2010
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Thin Cd(2)Nb(2)O(7) films were grown on single-crystal p-type SiO(2)/Si substrates by the metallo-organic decomposition (MOD) technique. The films were investigated by X-ray diffraction, X-ray energy-dispersive spectroscopy, and field emission scanning electron microscopy, and showed a single phase (cubic pyrochlore), a crack-free spherical grain structure, and nanoparticles with a mean size of about 68 nm. A Cauchy model was also used in order to obtain the thickness and index of refraction of the stack layers (transparent layer/SiO(2)/Si) by spectroscopic ellipsometry (SE). The dielectric constant (K) of the films was calculated to be about 25 from the capacitance-voltage (C-V) measurements. (c) 2008 Elsevier Ltd. All rights reserved.
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We present experimental evidence of the existence of cell variability in terms of threshold light dose for Hep G2 (liver cancer cells) cultured. Using a theoretical model to describe the effects caused by successive photodynamic therapy (PDT) sessions, and based on the consequences of a partial response we introduce the threshold dose distribution concept within a tumor. The experimental model consists in a stack of flasks, and simulates subsequent layers of a tissue exposed to PDT application. The result indicates that cells from the same culture could respond in different ways to similar PDT induced-damages. Moreover, the consequence is a partial killing of the cells submitted to PDT, and the death fraction decreased at each in vitro PDT session. To demonstrate the occurrence of cell population modification as a response to PDT, we constructed a simple theoretical model and assumed that the threshold dose distribution for a cell population of a tumor is represented by a modified Gaussian distribution.
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The design of binary morphological operators that are translation-invariant and locally defined by a finite neighborhood window corresponds to the problem of designing Boolean functions. As in any supervised classification problem, morphological operators designed from a training sample also suffer from overfitting. Large neighborhood tends to lead to performance degradation of the designed operator. This work proposes a multilevel design approach to deal with the issue of designing large neighborhood-based operators. The main idea is inspired by stacked generalization (a multilevel classifier design approach) and consists of, at each training level, combining the outcomes of the previous level operators. The final operator is a multilevel operator that ultimately depends on a larger neighborhood than of the individual operators that have been combined. Experimental results show that two-level operators obtained by combining operators designed on subwindows of a large window consistently outperform the single-level operators designed on the full window. They also show that iterating two-level operators is an effective multilevel approach to obtain better results.
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Sterners Specialfabrik AB tillverkar bland annat mynt- och biljettautomater. För att underlätta felsökning, underhåll, avläsning av statistik med mera på en automat är det lämpligt att detta utförs på en PC över Internet. Det innebär att automaten inte behöver besökas då dessa uppgifter skall utföras. Examensarbetet går ut på att få en PIC mikrokontroller att kommunicera med en användare vid en PC över internet. För detta krävs att en TCP/IP stack implementeras på PICmikrokontrollern. Arbetet ledde till en fungerande demoapplikation som klarar av att kommunicera över TCP/IP. Demoapplikationen innehåller diverse olika funktioner för att demonstrera hur en automat skulle kunna styras och övervakas.
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Internet protocol TV (IPTV) is predicted to be the key technology winner in the future. Efforts to accelerate the deployment of IPTV centralized model which is combined of VHO, encoders, controller, access network and Home network. Regardless of whether the network is delivering live TV, VOD, or Time-shift TV, all content and network traffic resulting from subscriber requests must traverse the entire network from the super-headend all the way to each subscriber's Set-Top Box (STB).IPTV services require very stringent QoS guarantees When IPTV traffic shares the network resources with other traffic like data and voice, how to ensure their QoS and efficiently utilize the network resources is a key and challenging issue. For QoS measured in the network-centric terms of delay jitter, packet losses and bounds on delay. The main focus of this thesis is on the optimized bandwidth allocation and smooth datatransmission. The proposed traffic model for smooth delivering video service IPTV network with its QoS performance evaluation. According to Maglaris et al [5] First, analyze the coding bit rate of a single video source. Various statistical quantities are derived from bit rate data collected with a conditional replenishment inter frame coding scheme. Two correlated Markov process models (one in discrete time and one incontinuous time) are shown to fit the experimental data and are used to model the input rates of several independent sources into a statistical multiplexer. Preventive control mechanism which is to be include CAC, traffic policing used for traffic control.QoS has been evaluated of common bandwidth scheduler( FIFO) by use fluid models with Markovian queuing method and analysis the result by using simulator andanalytically, Which is measured the performance of the packet loss, overflow and mean waiting time among the network users.
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The purpose of this project is to update the tool of Network Traffic Recognition System (NTRS) which is proprietary software of Ericsson AB and Tsinghua University, and to implement the updated tool to finish SIP/VoIP traffic recognition. Basing on the original NTRS, I analyze the traffic recognition principal of NTRS, and redesign the structure and module of the tool according to characteristics of SIP/VoIP traffic, and then finally I program to achieve the upgrade. After the final test with our SIP data trace files in the updated system, a satisfactory result is derived. The result presents that our updated system holds a rate of recognition on a confident level in the SIP session recognition as well as the VoIP call recognition. In the comparison with the software of Wireshark, our updated system has a result which is extremely close to Wireshark’s output, and the working time is much less than Wireshark. In the aspect of practicability, the memory overflow problem is avoided, and the updated system can output the specific information of SIP/VoIP traffic recognition, such as SIP type, SIP state, VoIP state, etc. The upgrade fulfills the demand of this project.
Resumo:
Internet protocol TV (IPTV) is predicted to be the key technology winner in the future. Efforts to accelerate the deployment of IPTV centralized model which is combined of VHO, encoders, controller, access network and Home network. Regardless of whether the network is delivering live TV, VOD, or Time-shift TV, all content and network traffic resulting from subscriber requests must traverse the entire network from the super-headend all the way to each subscriber's Set-Top Box (STB). IPTV services require very stringent QoS guarantees When IPTV traffic shares the network resources with other traffic like data and voice, how to ensure their QoS and efficiently utilize the network resources is a key and challenging issue. For QoS measured in the network-centric terms of delay jitter, packet losses and bounds on delay. The main focus of this thesis is on the optimized bandwidth allocation and smooth data transmission. The proposed traffic model for smooth delivering video service IPTV network with its QoS performance evaluation. According to Maglaris et al [5] first, analyze the coding bit rate of a single video source. Various statistical quantities are derived from bit rate data collected with a conditional replenishment inter frame coding scheme. Two correlated Markov process models (one in discrete time and one in continuous time) are shown to fit the experimental data and are used to model the input rates of several independent sources into a statistical multiplexer. Preventive control mechanism which is to be including CAC, traffic policing used for traffic control. QoS has been evaluated of common bandwidth scheduler( FIFO) by use fluid models with Markovian queuing method and analysis the result by using simulator and analytically, Which is measured the performance of the packet loss, overflow and mean waiting time among the network users.
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This dissertation is focused on theoretical and experimental studies of optical properties of materials and multilayer structures composing liquid crystal displays (LCDs) and electrochromic (EC) devices. By applying spectroscopic ellipsometry, we have determined the optical constants of thin films of electrochromic tungsten oxide (WOx) and nickel oxide (NiOy), the films’ thickness and roughness. These films, which were obtained at spattering conditions possess high transmittance that is important for achieving good visibility and high contrast in an EC device. Another application of the general spectroscopic ellipsometry relates to the study of a photo-alignment layer of a mixture of azo-dyes SD-1 and SDA-2. We have found the optical constants of this mixture before and after illuminating it by polarized UV light. The results obtained confirm the diffusion model to explain the formation of the photo-induced order in azo-dye films. We have developed new techniques for fast characterization of twisted nematic LC cells in transmissive and reflective modes. Our techniques are based on the characteristics functions that we have introduced for determination of parameters of non-uniform birefringent media. These characteristic functions are found by simple procedures and can be utilised for simultaneous determination of retardation, its wavelength dispersion, and twist angle, as well as for solving associated optimization problems. Cholesteric LCD that possesses some unique properties, such as bistability and good selective scattering, however, has a disadvantage – relatively high driving voltage (tens of volts). The way we propose to reduce the driving voltage consists of applying a stack of thin (~1µm) LC layers. We have studied the ability of a layer of a surface stabilized ferroelectric liquid crystal coupled with several retardation plates for birefringent color generation. We have demonstrated that in order to accomplish good color characteristics and high brightness of the display, one or two retardation plates are sufficient.
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A newsletter published periodically to keep the faculty, students, staff, and community informed about the activities taking place on the campus of LaGuardia Community College Cover article: SEVEN DISTINGUISHED GUESTS TO ATTEND SYMPOSIUM ON LAGUARDIA & ETHNIC VOTE. Other entries: BHE ADOPTS TENURE GUIDELINES AND IMPLEMENTATION STEPS; OVERFLOW AUDIENCE ATTENDS POST VISIONS OF WAR SYMPOSIUM; LAGUARDIA FLYERS SEEK FIRST BASKETBALL WIN; DIVISION OF CONTINUING EDUCATION BEGINS 3RD YEAR WITH WINTER PROGRAM; TYPING FOR HANDICAPPED PROGRAM SEEKS ADDITIONAL STUDENTS.
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Neste trabalho estuda-se o processo de flotação por ar dissolvido (FAD) como método de remoção de óleos emulsificados. Realizou-se uma revisão bibliográfica tanto do processo de flotação como dos fundamentos físico-químicos envolvidos na estabilidade e flotação de emulsões. Foram realizados testes de estabilidade de emulsões, de FAD descontínuos e contínuos, utilizando-se emulsões de 1000 mg/l de Óleo diesel e heptano. Verificou-se a eficiência do sulfato de alumínio e de compostos poliméricos como agentes desestabilizantes. Estudou-se a influência do tipo e concentração dos agentes desestabilizantes, pH da emulsão, do tipo de água e agitação nos testes de estabilidade como também na flotação por ar dissolvido. Os resultados obtidos indicaram a viabilidade técnica da aplicação do processo para a clarificação de efluentes oleosos atingindo valores de turbidez residual satisfatórios (menores que 5 UNT). O sulfato de alumínio mostrou-se mais eficiente como agente desestabilizante de ambas emulsões nos estudos de estabilidade e testes de PAD descontínuos, mas o polímero catiônico C-505 apresentou melhores resultados nos testes de flotação contínuos. O presente trabalho ainda apresenta um estudo de dimensionamento e do custo da unidade de FAD para remoção de óleos emulsificados que leva em consideração os custos de investimentos e de operação da unidade. Verifica-se que o custo total da unidade depende da vazão de alimentação, taxa de recirculação, taxa ar/sólido em massa e concentração inicial de óleos. Conclui-se que para as taxas de ar/sólido usados na indústria (geralmente menores que 0,1) o custo operacional do reagente é o parâmetro determinante do custo total atualizado da unidade. Isto faz com que o custo total atualizado seja essencialmente independente da relação taxa de aplicação - taxa ar/sólido.
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No processo de desdobramento dos blocos de granito e basalto, os teares utilizam granalha de ferro/aço como abrasivo gerando grandes quantidades de material fino a base dos minerais constituintes das rochas, da granalha cominuída e do desgaste das lâminas (lama abrasiva). Este trabalho tem por objetivo caracterizar a lama abrasiva no estágio em que esta sai do processo de desdobramento das rochas (rejeito). Isto acontece quando a granalha atinge a fração < 0,42 mm e perde suas propriedades abrasivas, dispensando, desta forma, sua presença no sistema. O equipamento utilizado para a retirada da lama não abrasiva é o hidrociclone, que através do overflow conduz o rejeito a uma bacia de decantação. A caracterização do rejeito foi realizada tanto em amostras individuais, como em amostras coletadas diretamente nos tanques de decantação provenientes da serragem de diferentes tipos litológicos, enfatizando, principalmente, os aspectos físicos (morfológico e granulométrico) que caracterizam esta lama não abrasiva. Este estudo busca, também, quantificar o volume produzido de rejeito pelas principais empresas de desdobramento do setor, bem como o provável aproveitamento econômico, através de métodos de separação mineral apropriados, de modo que se determine uma rota viável na ordem técnica e econômica. Outro aspecto abordado foi o impacto ambiental gerado pela deposição destes rejeitos, uma vez que, poucas empresas do setor têm a preocupação efetiva de adequar suas bacias de decantação com as normas vigentes da legislação ambiental. Após o esgotamento dessas bacias, os rejeitos são descartados em aterros próximos às empresas ou nos “lixões” e aterros das prefeituras municipais. Observa-se, desta forma, que não há o devido tratamento, haja vista, o material apresentar elevado percentual de sólidos (ferro, quartzo, feldspato) e pH em torno de 12 (alcalino).
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O tema da responsabilidade social empresarial vem ganhando força e atenção tanto das organizações empresariais quanto da sociedade civil. Os impactos do mundo pós-guerra, da globalização e do desenvolvimento somam consequências ambientais, sociais e poluição. Como atores inseridos nessas realidades, as empresas também sofrem as consequências destas mudanças. O próprio papel das organizações na sociedade e os limites e alcances de sua atuação recebem novas perspectivas. A conjuntura atual traz às empresas novos desafios e possibilidades no que se refere à Responsabilidade Corporativa. Estas mudanças têm impacto na própria organização da empresa (seus objetivos, relacionamento com consumidores, trabalhadores etc.) e, como consequência, em suas próprias estratégias. Grande parte das ações de Responsabilidade Corporativa se baseia em visões estreitas de atuação – essencialmente, uma postura reativa, como consequência de pressões e obrigações. No entanto, tem-se observado a ascensão de uma nova proposta, mais proativa: em algumas empresas pioneiras, a Responsabilidade Corporativa é vista como parte integrante e fundamental da estratégia empresarial, gerando benefícios não apenas para a sociedade, mas também para a própria empresa. O presente trabalho inicia-se com uma investigação da literatura sobre a evolução da Responsabilidade Social. Em seguida, propõe-se um modelo conceitual, relacionando Responsabilidade Corporativa e Estratégia, o qual expõe os caminhos possíveis de integração entre estes. Parte-se, portanto da ideia de que a Responsabilidade Corporativa pode ser abordada como uma questão estratégica, capaz de atender, em diferentes níveis e profundidades, pontos cruciais para o bom desempenho empresarial. A aplicabilidade do modelo proposto é demonstrada através da análise de exemplos ilustrativos de empresas que vêm incorporando a Responsabilidade Corporativa como parte integrante de sua estratégia de negócio. Como conclusão, constata-se que, quando é parte de uma estratégia formal, a adoção de uma abordagem responsável não só traz ganhos de imagem, mas também gera, para empresas que a praticam, resultados tangíveis, ao mesmo tempo em pode assegurar, para a Sociedade, um mundo mais sustentável, com melhor qualidade de vida para todos.
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Esta animação descreve as representações de números binários sem sinal, representação de sinal e magnitude, complemento de 1, complemento de 2. Também são apresentadas a adição de números sem sinal, a subtração em complemento de 2, o conceito de overflow e exceção. O projeto de uma unidade lógica e aritmética (ULA) é descrito, assim como alguns exemplos das operações: slt e beq. Três versões da operação de multiplicação, que é mais complicada que a de soma, são apresentadas por meio de figuras e algoritmos. A representação de ponto flutuante e o padrão IEEE 754 também são descritos.