O tênis de mesa é um dos esportes de raquete mais rápidos do mundo, exigindo muito pouco tempo para planejar e executar seus movimentos. Neste sentido, detectar a quantidade de rotação da bola, velocidade e direção torna-se fundamental para produzir respostas motoras eficientes. Entretanto, existem algumas questões que ainda não foram exploradas como o quanto a disponibilidade das informações auditiva e visual interfere na acurácia da percepção da rotação da bola e no tempo necessário para perceber estas rotações. O propósito do presente estudo foi analisar a influência da informação auditiva e visual na percepção da rotação da bola e no desempenho no tênis de mesa. Os atletas profissionais foram submetidos a dois estudos: o primeiro destinado a verificar a contribuição da informação auditiva e visual na percepção da rotação da bola e no tempo necessário para essa percepção. O segundo, proposto para avaliar a influência da informação auditiva no desempenho da tarefa de contra-ataque no tênis de mesa. Participaram do estudo 22 mesatenistas de alto rendimento de ambos os sexos (21 homens e 1 mulher) com média de idade de 22,55 ± 6,15. O teste de percepção de rotação (estudo 1) analisou o número de acertos e o tempo de reação por meio de uma rotina desenvolvida no software Matlab (Apêndice D). Os atletas visualizavam a tela de um computador e respondiam em um teclado o mais rápido possível. Os atletas analisaram um movimento de forehand nas intensidades de rotação: muita rotação (bola girando a aproximadamente 140 r/s); média (bola girando a aproximadamente 105 r/s); pouca rotação (bola girando a aproximadamente 84 r/s); batida chapada (bola girando a aproximadamente 70 r/s), nas seguintes condições: a) informação auditiva; b) informação visual; c) informação auditiva e visual. Os atletas analisaram 20 bolas para cada condição sendo cinco de cada tipo de efeito. Para o teste de desempenho (estudo 2) o atleta teve que responder adequadamente com o movimento de contra-ataque de forehand em um alvo previamente marcado na mesa. Foram golpeadas 80 bolas nas mesmas intensidades de rotação mencionadas acima. Os atletas foram avaliados em duas condições: com informação auditiva e sem informação auditiva. Os resultados do estudo 1 revelaram que mesatenistas foram capazes de perceber a magnitude de rotação da bola nas três condições. O percentual de acertos foi de 77,5%, 91,14% e 96,36% para as condições de informação auditiva, visual e combinadas, respectivamente. Quanto ao tempo de reação, os resultados revelaram que na condição somente informação auditiva (2,32 ± 0,41 s) os atletas demoraram mais tempo para responder do que em relação a condição somente informação visual (2,07 ± 0,36 s), já na condição informação auditiva e visual (1,85 ± 0,35 s) os atletas se mostraram mais rápidos ainda concordando com as informações número de acertos obtidas neste estudo. Para o estudo 2 os resultados revelaram que quando os atletas contra-atacaram na condição informação auditiva, o número de acertos foi de 37,69 ± 5,43 enquanto, quando a audição dos atletas foi privada a média de acertos foi 33,15 ± 6,84. Os resultados apontaram que mesatenistas foram capazes de utilizar as informações auditiva e visual para perceber a magnitude da rotação da bola no golpe forehand, porém, no estudo 1 quando as informações foram combinadas o número de acertos aumentou 5,22% e o tempo de reação diminuiu 0,22 s. No estudo 2 Quando a informação auditiva foi privada houve uma diminuição na média do número de acertos de 4,54. / Table tennis is one of the fastest racket sports in the world, requiring very little time to plan and execute your moves. In this sense, detecting a quantity of ball spin, velocity and direction becomes fundamental to produce efficient motor responses. However, there are some questions that have not yet been explored for example how much the availability of auditory and visual information interferes with the accuracy of the perception of the rotation of the ball and the time needed to perceive these rotations. The purpose of the present study is to analyze the influence of auditory and visual information on the perception of ball rotation and performance in table tennis. The volunteers were submitted to two studies: the first one to verify the contribution of the auditory and visual information in the perception of the rotation of the ball and in the time necessary for this perception. The second, proposed to evaluate the influence of auditory information on the performance of the counter-attack task in table tennis. Twenty-two high-level table tennis players men and women (21 men and 1 woman) with a mean age of 22.55 ± 6.15 participated in the study. The rotation perception test (study 1) analyzed the number of hits and the reaction time through a routine developed in Matlab software. The athletes visualized the screen of a computer and answered in a keyboard as soon as possible. The athletes analyzed a forehand movement in the rotation intensities: fast spin (spinning ball foward at 140 r/s); medium spin (105 r/s); slow spin (84 r/s); flat hit (70 r/s), under the following conditions: a) auditory information; b) visual information; c) auditory and visual information. The athletes analyzed 20 balls for each condition, five of each type of rotation. For the performance test (study 2) the athlete had to respond adequately with the forehand counterattack movement on a previously marked target at the table. 80 balls were struck at the same intensities of rotation mentioned above. The athletes were evaluated in two conditions: with auditory information and without auditory information. The results of the study 1 revealed that table tennis players were able to perceive the magnitude of rotation of the ball in the three conditions. The percentage of correct answers was 77.5%, 91.14% and 96.36% for auditory, visual and combined information conditions, respectively. Regarding the reaction time, the results revealed that in the condition only auditory information (2.32 ± 0.41 s) the athletes took more time to respond, since in the condition only visual information (2.07 ± 0.36 s) delayed a little less and in the condition auditory and visual information (1.85 ± 0.35 s) the athletes showed themselves to be faster still agreeing with the information number of hits obtained in this study. For the study 2 the results revealed that when the athletes counterattacked in the auditory information condition, the number of hits was 37.69 ± 5.43, whereas when the hearing of the athletes was private the average hit was 33.15 ± 6.84. The results indicated that table tennis players were able to use auditory and visual information to realize the magnitude of the ball rotation in the forehand blow, however, in study 1 when the informations were combined the number of right answered increased 5.22% and the reaction time decreased by 0.22 s. In study 2 When the auditory information was depriving, there was a decrease in the average number of hits 4.54.

Let G be a group. A Weak Cayley Table mapping ϕ : G → G is a bijection such that ϕ(g1g2) is conjugate to ϕ(g1)ϕ(g2) for all g1, g2 in G. The set of all such mappings forms a group W(G) under composition. We study W(G) for the seventeen wallpaper groups G.

We review some computational aspects of motor control. The problem of trajectory control is phrased in terms of an efficient representation of the operator connecting joint angles to joint torques. Efficient look-up table solutions of the inverse dynamics are related to some results on the decomposition of function of many variables. In a biological perspective, we emphasize the importance of the constraints coming from the properties of the biological hardware for determining the solution to the inverse dynamic problem.

No description available.

Rapporten behandlar utvecklingsarbetet av ett nytt gåbord i samarbete med Skaraborgs sjukhus. Målet med arbetet var delvis att lokalisera och lösa de problem som fanns med det befintliga gåbordet. Samt utöver detta utveckla och göra bordet ergonomiskt anpassat för både vårdare och patient. Arbetet är uppdelat i bakgrund, förstudie, idégenerering, konceptutveckling och till sist ett resultat. I förstudien har de olika gåbord som finns på marknaden studerats och vilka problem det finns med dessa genom intervjuer med berörda parter. Genom en innehållsrik kravspecifikation och riktlinjer från Svensk standard (ISO-11199, 2005) har arbetet haft tydliga ramar för den utvecklande processen. Med hjälp av ett antal kreativitetsmetoder har ett stort antal lösningar hittats som efter en utvärdering gallrats till ett fåtal kvarvarande. Efter det följande utvecklingsarbetet har dessa idéer förbättrats till ett slutgiltigt koncept, en produkt som möter de krav som satts upp. / This report deals with the development of a new walking table in cooperation with the hospitals in Skaraborg. The goal was partally to locate and solve the problems that existed with the walking aid, and with a usability outlook develop the table to suit both nurses and patients. The work is divided into a literature study, idea generation, concept development and finally a result part. In the preliminary study, the group looked at various walking tables available on the market today and what problems there are with them through interviews. Through a comprehensive specification of requirements and guidelines from the Swedish standard association, the work could go on to the developing process. With the help of some different creativity techniques, a large number of solutions where found, and after evaluating these solutions a smaller amount of concepts could be developed futher. After improvement of these ideas, the project resulted in a product that met the requirements set by the user and project team.

The first topic of this thesis is a mixed radix-16/8/4/2 64b/32b integer divider which uses a variety of techniques, including operand scaling, table partitioning, and table sharing, to increase performance without paying the cost of increasing complexity. The second topic is a noise immune address transition detector¡]ATD¡^circuit. We employ a simple feedback loop to stabilize the generated CS¡]chip select¡^signal and two delay cells to dynamically adjust the width of the CS strobe.

Encryption, digital signature and digital watermark are three popular methods to prevent a wide variety of multimedia products from illegal copy or subterfuge attacks. In particular, digital watermarking recently draws a lot of attention since it hides desirable information in transmitted audio, image and video data files without affecting much the data quality. The thesis proposes two watermarking methods for audio and image data. And both watermarking methods embed watermark signals in the spatial/time domain using a so-call Pixel Weight Table. The experiment results shows that the two methods have good performance. In addition, I propose a guantitive measuring method, called APSNR, to characterize the audio perceptual transparency.

<p>Rapporten behandlar utvecklingsarbetet av ett nytt gåbord i samarbete med Skaraborgs sjukhus. Målet med arbetet var delvis att lokalisera och lösa de problem som fanns med det befintliga gåbordet. Samt utöver detta utveckla och göra bordet ergonomiskt anpassat för både vårdare och patient. Arbetet är uppdelat i bakgrund, förstudie, idégenerering, konceptutveckling och till sist ett resultat. I förstudien har de olika gåbord som finns på marknaden studerats och vilka problem det finns med dessa genom intervjuer med berörda parter. Genom en innehållsrik kravspecifikation och riktlinjer från Svensk standard (ISO-11199, 2005) har arbetet haft tydliga ramar för den utvecklande processen. Med hjälp av ett antal kreativitetsmetoder har ett stort antal lösningar hittats som efter en utvärdering gallrats till ett fåtal kvarvarande. Efter det följande utvecklingsarbetet har dessa idéer förbättrats till ett slutgiltigt koncept, en produkt som möter de krav som satts upp.</p> / <p>This report deals with the development of a new walking table in cooperation with the hospitals in Skaraborg. The goal was partally to locate and solve the problems that existed with the walking aid, and with a usability outlook develop the table to suit both nurses and patients. The work is divided into a literature study, idea generation, concept development and finally a result part. In the preliminary study, the group looked at various walking tables available on the market today and what problems there are with them through interviews. Through a comprehensive specification of requirements and guidelines from the Swedish standard association, the work could go on to the developing process. With the help of some different creativity techniques, a large number of solutions where found, and after evaluating these solutions a smaller amount of concepts could be developed futher. After improvement of these ideas, the project resulted in a product that met the requirements set by the user and project team.</p>

Thesis--M. Phil., University of Hong Kong, 1983.

The goal of the project is to develop, build, and test a modular steel structure that can be tested on an educational shaking table to demonstrate structural dynamic and earthquake engineering principles. The advantage of the structure is that it can be tested into its non-linear range and yielded parts can easily be replaced for subsequent tests. The steel modular structure represents a multi-story moment resisting frame and is comprised of sheet metal beams and columns bolted to “rigid” steel angles. This structure is tested on a unidirectional shaking table, viz. “Quanser Shake Table II”. The structure is designed to achieve a specific mode of failure through non-linear analysis. A non-linear pushover analysis is carried out to determine stiffness and strength of the structure as well as potential hinge locations. Eigen-value analysis is undertaken to determine all the natural periods and frequencies that will help in understanding its dynamic response. The structure is analyzed and tested for various ground motions to study the effects of an earthquake on a multi-storied frame. Educational modules provide a set of experiments that can be easily performed on the test structure. / text