2D transition metal carbides and/or nitrides, so-called MXenes, are noted as ideal fast-charging cation-intercalation electrode materials, which nevertheless suffer from limited specific capacities. Herein, it is reported that constructing redox-active phosphorus−oxygen terminals can be an attractive strategy for Nb4C3 MXenes to remarkably boost their specific capacities for ultrafast Na+ storage. As revealed, redox-active terminals with a stoichiometric formula of PO2- display a metaphosphate-like configuration with each P atom sustaining three P-O bonds and one P=O dangling bond. Compared with conventional O-terminals, metaphosphate-like terminals empower Nb4C3 (denoted PO2-Nb4C3) with considerably enriched carrier density (fourfold), improved conductivity (12.3-fold at 300 K), additional redox-active sites, boosted Nb redox depth, nondeclined Na+-diffusion capability, and buffered internal stress during Na+ intercalation/de-intercalation. Consequently, compared with O-terminated Nb4C3, PO2-Nb4C3 exhibits a doubled Na+-storage capacity (221.0 mAh g-1), well-retained fast-charging capability (4.9 min at 80% capacity retention), significantly promoted cycle life (nondegraded capacity over 2000 cycles), and justified feasibility for assembling energy−power-balanced Na-ion capacitors. This study unveils that the molecular-level design of MXene terminals provides opportunities for developing simultaneously high-capacity and fast-charging electrodes, alleviating the energy−power tradeoff typical for energy-storage devices.

International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / This paper describes a system of Total Border Surveillance, which is cost effective, closes existing gaps and is less manpower intensive than the current techniques. The system utilizes a fleet of commercially available aircraft converted to unmanned capability, existing GPS and surveillance systems and autonomous ground stations to provide the desired coverage.

Thesis (MScPhysio)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The aim of this study was to improve the measurement of postural dynamism in the sitting position using a three-dimensional (3D) motion analysis system. The primary objective was to describe pilot data for postural dynamism of the cervical and thoracic spines while working at a desktop computer. The secondary objective was to refine the process of posture measurement and analysis by decreasing data processing time. Certain factors in 3D motion analysis can lead to an increase in gaps in data collected during trial capture, which in turn will lead to a longer time of data processing. In the first phase of this study, a number of such factors were identified and altered. A series of pilot studies was performed to test the improvement of data processing time when altering these factors. In the first two pilot studies, camera and tripod positionings were explored and refined, workstation layout and anatomical landmark marker placement were investigated, and optimal capture frequency was established. In both these pilot studies, outcomes were established by means of trial and error by experimenting with a variety of different options for the different outcomes. In the third pilot study, computer software which provides computer tasks for the participant during primary trial capture was tested. Two independent computer users performed all the activities as per software, after which they were required to give oral feedback and suggestions on improvement in terms of user friendliness. The objective of the fourth and final pilot study was to include all of the outcomes from the preceeding pilot studies and attempt a trial run of the actual data collection process. A study participant with no affiliation to the research project was used and a complete trial run was performed after which the measurement process was deemed feasible. In the primary study, 18 student volunteers completed a sequence of computer tasks, including keyboard, mouse and reading activities. Prior to data capture, full range of motion of the thoracic and cervical spines were measured in three dimensions for every participant. Data capture took place for the full duration of performance of all computer activities. Outcome parameters for postural dynamism included true range of motion (degrees), proportional range of motion (percentage) and motion frequency (movement per minute) in all three planes of motion of the cervical and thoracic spines. Typing tasks were associated with biggest movement ranges and motion frequencies. Mouse activity was associated with the most stationary posture, exhibiting the least frequent movement as well as the smallest ranges of motion. The results from this study allow us to better understand the dynamic nature of posture, as well as postural dynamism associated with different computer tasks. This study provides a baseline for future research of 3D motion analysis of the sitting posture. It also marks the need for further research regarding ergonomics, use and potential alternatives in the computer workstation and input devices. / AFRIKAANSE OPSOMMING: Hierdie studie het ten doel gehad om die meting van posturale dinamisme in die sitposisie te verbeter deur middel van „n drie-dimensionele (3D) bewegingsanalisesisteem. Die primêre doelwit was om loodsdata te beskryf vir posturale dinamisme van die servikale en torakale werwelkolomme terwyl op „n rekenaar gewerk word. Die sekondêre doelwit was om die proses van postuurmeting en analise te verfyn deur die dataprosesseringstyd te verminder. Sekere faktore van 3D bewegingsanalise kan „n vermeerdering van gapings in ingesamelde data tot gevolg hê, wat weer kan lei na „n verlengde tydperiode van dataprosessering. In die eerste fase van hierdie studie is sulke faktore identifiseer en aangepas. „n Reeks loodsstudies is uitgevoer om die verbetering van dataprosesseringstyd te toets namate aanpassings aan hierdie faktore gemaak is. Tydens die eerste twee loodsstudies is verskillende kamera en driepoot posisionering ondersoek en verfyn, werkstasie uitleg en anatomiese baken merker plasing is ondersoek en die optimale dataversamelingsfrekwensie is vasgestel. In beide hierdie loodsstudies is die uitkomste vasgestel op grond van toets- en fouteer deur te eksperimenteer met „n verskeidenheid opsies soos van toepassing op die betrokke uitkomste. Tydens die derde loodsstudie is rekenaarsagteware getoets wat die rekenaaraktiwiteit vir die studiedeelnemers verskaf het tydens primêre data-insameling. Twee onafhanklike persone het al die aktiwiteite volgens die sagteware voltooi en het verbale terugvoer en aanbevelings gegee oor hoe om die program te verbeter. Die vierdie en finale loodsstudie het gepoog om al die uitkomste van die eerste drie loodsstudies in te sluit en „n toetsmeting te doen van die ware dataversamelingsproses. „n Onafhanklike studiedeelnemer met geen affiliasie tot die navorsingsprojek nie het „n toetslopie van die hele versamelingsproses gedoen en die metingsproses is haalbaar verklaar. Tydens die primêre studie het 18 student-vrywilligers „n reeks rekenaartake gedoen (insluitend sleutelbord en muisaktiwiteite sowel as „n leesopdrag). Voor die aanvang van dataversameling is die volle bewegingsomvange van die torakale en servikale werwelkolomme van elke deelnemer gemeet. Dataversameling is vir die volle durasie van die uitvoer van rekenaaraktiwiteite gedoen. Uitkomsparameters vir posturale dinamisme het die volgende ingesluit: Omvang van beweging (grade), proporsionele omvang van beweging (persentasie) en bewegingsfrekwensie (bewegings per minuut) in al drie bewegingsvlakke van die servikale en torakale werwelkolomme. Sleutelbord-aktiwiteite is geässosieer met die grootste bewegingsomvange en die meeste bewegingsfrekwensie. Muisaktiwiteit is geässosieer met die mees stasionêre postuur en het die heel minste gereelde beweging getoon in die algemeen. Die resultate van hierdie studie help om die dinamise natuur van postuur beter te verstaan, sowel as posturale dinamisme wat met verskillende rekenaartake verbind word. Die studie bied „n basislyn vir die toekomstige navorsings wat posturale dinamisme met verskillende rekenaartake meet. Dit merk ook die behoefte aan verdere navorsing aangaande ergonomika, gebruik en alternatiewe tot rekenaarwerkstasie en –toerusting.

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

published_or_final_version / Transport Studies / Master / Master of Arts

published_or_final_version / Urban Planning / Master / Master of Science in Urban Planning

This study is concerned with determining the effects that video display terminal use had on reporters' and editors' attitudes toward their jobs and the machines themselves. Data for this investigation were obtained with questionnaires returned from seventy-one reporters and editors who use video terminals in their daily work. Questionnaire data were supplemented with interview data from thirteen questionnaire respondents, Ten hypotheses in five categories were tested with the t test. Four additional hypotheses were tested with raw data. Findings showed that video terminal use enhanced perceived job professionalism and made respondents think they should make more money. Attitudes toward video terminals improved after use of the devices, and respondents recognized the value of video terminal training in college,

Contratos de concessão de serviços públicos em setores de infraestrutura, e particularmente no setor portuário, deverão passar por um período de revisões contratuais no Brasil. O prazo de concessões realizadas na década de 1990 está se encerrando, e alterações substanciais nas condições de diversos contratos realizadas sem a devida preocupação com os impactos no equilíbrio econômico-financeiro aumentam a complexidade nos processos de renegociação. A renegociação de contratos de concessão é um tema de grande foco acadêmico, por ser uma grande fonte de ineficiências e custos de transação em concessões de serviços públicos, podendo eliminar os benefícios do processo de competição via licitação e acarretar em maiores tarifas e/ou menor qualidade no serviço aos usuários. Nesse contexto, esta dissertação tem como objetivo contribuir com os aspectos metodológicos associados ao reequilíbrio econômico-financeiro de contratos de concessão, com aplicação específica em arrendamentos do setor portuário. As mudanças no ambiente regulatório devem visar um aumento de transparência e previsibilidade no processo de renegociação, com vistas a garantir que serviços públicos sejam prestados de forma adequada e universal (objetivo do Poder Público) e que o agente privado receba uma remuneração justa em relação aos investimentos realizados. Ainda que os princípios sejam claros, a revisão de contratos firmados com o Poder Público e a quantificação de eventuais desequilíbrios não são exercícios 100% unívocos. A falta de dados históricos confiáveis e a sobreposição de fatores ordinários e extraordinários dificultam a definição de parâmetros e exigem uma arquitetura meticulosa para estabelecer a álgebra mais adequada e conceber uma solução satisfatória. / In Brazil, the first cycle of concession contracts of transport infrastructure assets is about to end, giving birth to a period of contract renegotiations. In the seaport industry, the concession contracts signed in the 1990s terminated or are about to expire. However, in most cases their clauses have not been adapted to meet the many factors that affected the implicit financial equilibrium, increasing the complexity of the renegotiation process. The renegotiation of concession contracts has been addressed in several academic works. The authors acknowledge that this process is a major source of inefficiencies and transaction costs in public service concessions, and may reduce or eliminate the benefits of competition through bidding processes, leading to higher costs and/or worst level of service to users. In this context, this thesis proposed a methodology to evaluate the financial equilibrium of concession contracts in seaport terminals, as well as to make sure this equilibrium is not affected whenever changes in contract conditions happen. Changes in regulatory framework should increase transparency and predictability of contract renegotiation processes, ensuring public services are properly provided and private agents investments are correctly recovered. Nevertheless, the concession contract renegotiations and the evaluation of the implicit financial equilibrium are usually difficult to accomplish due to lack of reliable data and miscomprehension of ordinary and extraordinary factors. As a result, is usually necessary to develop detailed and ad hoc approaches to achieve a satisfactory solution both for government and private parties.

Este trabalho visa identificar, a partir de um levantamento de dados dos fluxos de cargas conteinerizadas e custos operacionais de transporte, os locais mais promissores para a instalação de futuros terminais intermodais de carga rodo-ferroviários, com auxílio de um Sistema de Informações Geográficas (TransCAD), objetivando a redução dos custos e otimização das operações logísticas envolvidas na rede de transportes do estado de São Paulo. Simulações são feitas para a instalação de até dez terminais intermodais rodo-ferroviários em pontos estratégicos do interior do Estado, considerando-se duas condições: a primeira com um terminal existente só em Santos e todos os pontos candidatos escolhidos pelo modelo de localização das p-medianas do TransCAD e, a segunda, considerando-se, além de Santos, os oito terminais intermodais já existentes no Estado. Apresenta-se uma análise dos custos de rede e os mapas temáticos de áreas de influência de cada uma das soluções obtidas pelo modelo. Os resultados são comparados com o trabalho de TONDO (1992). Conclui-se que as soluções encontradas através de um novo enfoque de modelagem do problema, são significativamente diferentes daqueles propostos por TONDO (1992). / Based on a data collection of containerized cargo flows and operational transport costs, this study has the objective of identifying promising points to install future road-rail intermodal container terminals, using a Geographic Information System (TransCAD) and the objective function of reducing costs and optimising logistic operations on the transport network of the state of São Paulo. Simulations are presented for the instalation of up to ten road-rail intermodal terminals at strategic locations in the interior of the State, considering two conditions: the first one, with only one terminal placed at the port of Santos and all the candidate points beeing chosen by the p-median location model of TransCAD, and the second one, considering Santos and the other eight existing intermodal terminals in the State. An analysis of the network costs and thematic maps of the influence areas of each solution are presented. The results are compared with the study by TONDO (1992). It is concluded that the solutions obtained by this new modeling focus of the problem, are considerably different from the ones obtained by TONDO (1992).

Esta pesquisa tem por objetivo principal investigar e avaliar as transformações ocorridas na organização espacial das estações ferroviárias, com o advento da sua integração física com a rede do metrô, na cidade de São Paulo, entre 1979, ano de inauguração da primeira estação integrada, a do Brás, e 2010, ano de inauguração da estação integrada Tamanduateí. São cinco estações delimitadas neste estudo, e que foram divididas em dois grupos: no primeiro, as de estruturas conectadas - Brás, Luz e Santo Amaro -; no segundo, as estações de estrutura compartilhada - Barra Funda e Tamanduateí. Este trabalho estrutura-se em cinco partes. Primeira: Conceitos gerais, objetivos e metodologia da pesquisa. Segunda: Análise das transformações na tipologia das estações ferroviárias, até o advento da integração modal. Terceira: Diretrizes para projetos de arquitetura de estações ferroviárias, de metrô e de integração modal. Quarta: Análise das cinco estações sob três aspectos: organização espacial da estação ferroviária e do metrô, integração física e atendimento ao fluxo de transferência. Quinta: As análises são cruzadas com as informações contidas no embasamento teórico, considerações finais. Cada estação apresenta as marcas das intervenções efetuadas em diferentes períodos na ferrovia. As análises das estações delinearam as diversas fases da integração intra-modal CPTM-Metrô na cidade de São Paulo, expondo pontos positivos, equívocos e seu estado atual / This research aims to investigate and to evaluate the changes occurring in the spatial organization of the railway stations, with the advent of the interchange with the metro network in the city of Sao Paulo, between 1979, opening´s year of the first station of this kind, Bras, and 2010, opening´s year of Tamanduatei. There are five stations defined in this study, and they were divided into two groups: in the first, the connected structures - Bras, Luz and Santo Amaro -; in the second, shared structure - Barra Funda and Tamanduatei. This study is divided into five parts. First: General concepts, objectives and research´s methodology. Second: Analysis of changes in the railway station´s types, until the advent of modal interchange. Third: Guidelines for architectural design of railway stations, subway and modal interchanges. Fourth: Analysis of the five stations under three aspects: spatial organization of the railway station and the subway, the interchange and attendance of the transfer. Fifth: the analyses are crossed with the information contained in the theoretical basis, concluding remarks. Each station has marks of interventions carried out at different periods of time in the railroad. The station´s analyses outlined the various stages of intra-modal interchange CPTMMetro in the city of Sao Paulo, exposing positive points, misconceptions and the current state