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Immediate and lasting improvements in weight distribution seen in baropodometry following a high-velocity, low-amplitude thrust manipulation of the sacroiliac joint

GRASSI, Daniel de Oliveira; SOUZA, Marcial Zanelli de; FERRARETO, Silvia Belissa; MONTEBELO, Maria Imaculada de Lima; GUIRRO, Elaine Caldeira de Oliveira
Fonte: CHURCHILL LIVINGSTONE Publicador: CHURCHILL LIVINGSTONE
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.62%
The biomechanics of the sacroiliac joint makes the pelvic segment responsible for proper weight distribution between lower extremities; however, it is known to be susceptible to altered mobility. The objective of this study was to analyze baropodometric responses following thrust manipulation on subjects with sacroiliac joint restrictions. Twenty asymptomatic subjects were submitted to computerized baropodometric analysis before, after, and seven days following sacroiliac manipulation. The variables peak pressure and contact area were obtained at each of these periods as the average of absolute values of the difference between the right and left foot based on three trials. Data revealed significant reduction only in peak pressure immediately after manipulation and at follow-up when compared to pre-manipulative values (p < 0.05). Strong correlation was found between the dominant foot and the foot with greater contact area (r - 0.978), as well as between the side of joint restriction and the foot with greater contact area (r = 0.884). Weak correlation was observed between the dominant foot and the foot with greater peak pressure (r = 0.501), as well as between the side of joint restriction and the foot with greater peak pressure (r = 0.694). The results suggest that sacroiliac joint manipulation can influence peak pressure distribution between feet...

Uma proposta de sistema robótico para manipulação e interação física segura em ambientes não estruturados; A proposal of a robotic manipulation system for safe physical interaction in non-structured environments

Pedro, Leonardo Marquez
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/06/2013 PT
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Este trabalho propõe um sistema de manipulação robótica para interação física segura com objetos ou humanos em ambientes não estruturados. A proposta considera a execução de tarefas de manipulação e a prevenção e tratamento de colisões utilizando apenas uma lei de controle, o controle de impedância. A inovação científica consiste em um sistema multifuncional implementado com uma única lei de controle em contraste com os sistemas já existem que utilizam chaveamento entre controladores para cada diferente funcionalidade do sistema, e que apresentam diversas desvantagens como instabilidade e oscilações, aumento da complexidade de programação, entre outras. Inicialmente é proposto um planejador de manipulação e regrasping baseado na combinação de trajetórias suaves e na adaptação dos parâmetros de um controle de impedância em tempo de execução. A mudança da impedância para cada etapa é obtida pela modificação dos parâmetros de inércia, rigidez e amortecimento do controlador. A estabilidade desta mudança dinâmica é possível pela utilização de trajetórias suaves obtidas com planejador Squeezed Screw modificado, cujas trajetórias geradas são livres de descontinuidades na posição e na velocidade. Adicionalmente...

Efeitos da manipulação na articulação sacroilíaca e transição lombossacral sobre os sinais de indivíduos portadores de instabilidade do tornozelo; Effects of manipulation on sacroiliac joint anda lumbossacral transition on the signs in individuals with ankle sprain

Gustavo Luiz Bortolazzo
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 24/02/2014 PT
Relevância na Pesquisa
36.62%
A manipulação articular é uma técnica utilizada na área de reabilitação física com o objetivo de aumentar a mobilidade articular e gerar respostas reflexas para diminuir a dor, melhorar o controle motor e a flexibilidade. Indivíduos com instabilidade do tornozelo apresentam alteração do controle motor no membro inferior homolateral ao tornozelo instável e alteração do controle postural, o que pode alterar a simetria entre os músculos posturais. A tese está apresentada em formato alternativo, com apresentação de 3 artigos, que têm como objetivos avaliar o efeito da técnica de manipulação articular na sacroilíaca e transição lombossacral sobre a atividade elétrica dos músculos que movem o tornozelo e a coluna lombar, sobre o limiar de dor à pressão, sobre a flexibilidade e sobre a assimetria dos músculos paravertebrais lombares ao nível de L5. Vinte voluntários foram divididos aleatoriamente em grupo experimental (n=10), em que os voluntários receberam manipulação na articulação sacroilíaca e transição lombossacral e grupo placebo (n=10), em que os voluntários receberam manobra sem efeitos terapêuticos. Foi realizada avaliação eletromiográfica dos músculos paravertebrais lombares ao nível de L5...

Dietary nutrient manipulation to improve the performance and tibia characteristics of broilers fed oak acorn (Quercus Brantii Lindl)

Houshmand,M; Hojati,F; Parsaie,S
Fonte: Fundação APINCO de Ciência e Tecnologia Avícolas Publicador: Fundação APINCO de Ciência e Tecnologia Avícolas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2015 EN
Relevância na Pesquisa
36.58%
An experiment was conducted to evaluate the effects of dietary nutrients (protein, methionine, and choline) manipulation on the performance and tibia characteristics of broilers fed diets containing 15% oak acorn. A completely randomized design with five treatments and four replicates of 15 chicks each, was used. One group was fed a diet based on corn (without oak acorn) as control and other four groups were fed diets containing oak acorn with one of the following nutrient manipulation: without nutrient manipulation, high level of methionine (100% more than NRC), high level of CP (10% more than NRC), and addition of 0.2% choline. Starter and finisher diets were fed from one to 21 and 22 to 42 d of age, respectively. The results indicated that group fed diet without nutrient manipulation presented higher feed intake and worse feed conversion ratio (p<0.05) compared with the control group throughout the experiment. Elevated levels of methionine, protein, and choline had significant beneficial effects on feed conversion ratio during starter phase. Feeding oak acorn negatively influenced tibia bone characteristics (bone ash and strength) both at 21 and 42 d of age, whereas the supplementation with protein, methionine and choline prevented those negative effects. In conclusion...

Influence of osteopathic manipulation on blood flow velocity of the cerebral circulation in chronic mechanical neck pain

Stelle,Rafael; Zeigelboim,Bianca Simone; Lange,Marcos C.; Marques,Jair Mendes
Fonte: Sociedade Brasileira para o Estudo da Dor Publicador: Sociedade Brasileira para o Estudo da Dor
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 EN
Relevância na Pesquisa
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BACKGROUND AND OBJECTIVES: Osteopathic manipulation is indicated for pain, myofascial tensions and/or decreased movement amplitude. This study aimed at checking whether osteopathic manipulation with cervical rhythmic articulatory technique generates abnormal blood flow velocity oscillations or risks to internal carotid, vertebral and basilar arteries circulation. METHODS: The sample was made up of 58 individuals with chronic mechanical cervical pain (40 females and 18 males), with mean age of 36 years, submitted to internal carotid, vertebral and basilar arteries ultrasound before and after a single osteopathic manipulation with cervical rhythmic articulatory technique. Individuals were evaluated by ultrasound in three moments: control evaluation, rest control evaluation and study evaluation. Separation was sequential and methods were randomly and blindly applied. RESULTS: Ultrasound has shown no significant differences in the comparison of flow velocity variables means among evaluations. However, a slight increase in vertebral, intracranial and basilar arteries blood flow was observed after osteopathic manipulation with cervical rhythmic articulatory technique in the study evaluation, without statistical significance. CONCLUSION: In this studied population...

Immediate effects of upper thoracic manipulation on the skin surface temperature of the vertebral region in healthy women

Packer,Amanda Carine; Dibai-Filho,Almir Vieira; Costa,Ana Cláudia de Souza; Macedo,Aline Barbosa; Bortolazzo,Gustavo Luiz; Rodrigues-Bigaton,Delaine
Fonte: Universidade de São Paulo Publicador: Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2015 EN
Relevância na Pesquisa
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Manipulation of the spinal column is a manual therapeutic resource characterized by passive thrust of a given joint at a high velocity and low amplitude within the limits of anatomic integrity. The objective of the present study was to assess the immediate effects of upper thoracic manipulation on skin temperature in the vertebral region in healthy women. Thus, a randomized controlled blind trial was realized in the university community. Twenty-six healthy women were randomly allocated into an experimental group (n=13) and a placebo group (n=13). A single session of upper thoracic spine manipulation (segment T3) was performed. Infrared thermography was used to determine changes in skin temperature in the vertebral region. Images were taken prior to, immediately after and both five and 10 minutes after manipulation. Two-way repeated measures analysis of variance with post hoc Bonferroni test was used for inter and intragroup comparisons. The level of significance was set to 5%. No significant differences were found between the different evaluation times in either group (p>0.05). In the intergroup analysis, no statistically significant differences were found in any of the comparisons (p>0.05). Based on the method employed, thoracic spine manipulation of the T3 vertebral segment does not promote changes in skin surface temperature in the region manipulated in asymptomatic individuals.

Learning Dextrous Manipulation Skills for Multifingered Robot Hands

Nelson, Randal C. ; Fuentes, Olac
Fonte: University of Rochester. Computer Science Department. Publicador: University of Rochester. Computer Science Department.
Tipo: Relatório
ENG
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We present a method for autonomous learning of dextrous manipulation skills with multifingered robot hands. We use heuristics derived from observations made on human hands to reduce the degrees of freedom of the task and make learning tractable. Our approach consists of learning and storing a few basic manipulation primitives for a few prototypical objects and then using an associative memory to obtain the required parameters for new objects and/or manipulations. The parameter space of the robot is searched using a modified version of the evolution strategy, which is robust to the noise normally present in real-world complex robotic tasks. Given the difficulty of modeling and simulating accurately the interactions of multiple fingers and an object, and to ensure that the learned skills are applicable in the real world, our system does not rely on simulation; all the experimentation is performed by a physical robot, in this case the 16-degree-of-freedom Utah/MIT hand. Experimental results show that accurate dextrous manipulation skills can be learned by the robot in a short period of time.

Manipulation of elections : algorithms and infeasibility results

Faliszewski, Piotr (1980 - ); Hemaspaandra, Lane A.
Fonte: University of Rochester Publicador: University of Rochester
Tipo: Tese de Doutorado Formato: Number of Pages:ix, 123 leaves
ENG
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Thesis (Ph. D.)--University of Rochester. Dept. of Computer Science, 2009.; Voting and elections are at the core of democratic societies. People vote to elect leaders, decide policies, and organize their lives, but elections also have natural applications in computer science. For example, agents in multiagent systems often need to work together to complete some task, but each agent may have its own set of beliefs, preferences, and goals. Voting provides agents with a natural way to reach decisions that take all their preferences into account. With elections playing such an important role both in real-life political settings and in computer science, it is natural to ask about their resistance to misuse. Two particular types of election misuse are manipulation and bribery. In manipulation, a group of voters chooses to misrepresent its preferences in order to obtain a more desirable outcome, and in bribery an outside agent, the briber, asks (possibly at a cost) a group of voters to change its votes, to obtain some outcome desirable for the briber. Classical results from political science show that, for any reasonable election system, there are scenarios where at least some voters have an incentive to attempt manipulation. In this thesis we seek to protect elections from manipulators and bribers by making their computational task of finding good manipulations/bribes prohibitively expensive. When this is not possible...

Nano-manipulation of single DNA molecules based on atomic force microscopy

Lu, Junhong; Li, Haikuo; An, Hongjie; Wang, Guo-Hua; Wang, Ying; Li, Minqian; Zhang, Yi; Li, Bin; Hu, Jun
Fonte: IEEE Publicador: IEEE
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
Relevância na Pesquisa
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Nano-manipulation of single atoms and molecules is a critical technique in nanoscience and nanotechnology. This paper will focus on the recent development of the manipulation of single DNA molecules based on atomic force microscopy (AFM) in our laboratory. Precise manipulation has been realized including varied manipulating modes such as "cutting", "pushing", "folding", "kneading", "picking up", "dipping", etc. The cutting accuracy is dominated by the size of the AFM tip, which is usually 10 nm or less. Single DNA fragments can be cut and picked up and then amplified by single molecule PCR. Thus positioning isolation and sequencing can be performed.; Lu Jun-Hong, Li Hai-Kuo, An Hong-Jie, Wang Guo-Hua, Wang Ying, Li Min -Qian, Zhang Yi, Li Bin and Hu Jun

Gezielter Beeinflussung der Fluxondynamik in Stapeln intrinsischer Josephson-Kontakte aus Bi_2Sr_2CaCu_2O_{8+x}; Aimed Manipulation of fluxon dynamics in stacks of intrinsic Josephson-junctions out of Bi_2Sr_2CaCu_2O_{8+x}

Oehmichen, Virginia
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
Relevância na Pesquisa
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Ziel der vorliegenden Arbeit war es, das Verständnis der Fluxondynamik intrinsischer Josephson-Kontakte aus BSCCO zu erweitern und diese Dynamik gezielt zu beeinflussen. Es wurden neue Ansätze zur Erzeugung von THz-Strahlung erforscht. Hierzu wurden Stufenstapel aus BSCCO mit Abmessungen von 1-3 µm Breite und 3-10 µm Länge präpariert. Der benötigte Fabrikationsprozess, basierend auf der doppelseitigen Technik von Wang et al., wurde etabliert. An den so hergestellten Proben wurden Transportmessungen ohne und mit Magnetfeld durchgeführt. Das Magnetfeld im Bereich einiger Tesla lag parallel zu den CuO_2-Doppelebenen an. Es konnten kollektive Plasmaresonanzen beobachtet werden. Diese waren im Vergleich zu den Resonanzen in Mesastrukturen~cite{Heim02} stabiler. Die Resonanzen lassen sich im unteren Strombereich einer außer-Phase-Konfiguration zuordnen, während es im oberen Strombereich aufgrund der Kombinationen mehrere mögliche Konfigurationen gibt. Die Fluxonenanordnung in einer außer-Phase-Konfiguration im unteren Strombereich wird ebenfalls gestützt durch an diesen Stufenstapeln gemessenen Flux-Flow-Oszillationen. Da die in-Phase-Konfiguration sich hier nicht eindeutig erkennen ließ, wurde die Fluxondynamik zur Erzeugung von THz-Strahlung gezielt beeinflusst durch die beiden folgenden Ansätze: * Steuerstrom * geometrische Beeinflussung: breitenmodulierter Stapel Zur elektronischen Beeinflussung wurde eine zusätzliche Stromleitung...

The Nature and Ethical Significance of Manipulation

Gorin, Moti
Fonte: Universidade Rice Publicador: Universidade Rice
Relevância na Pesquisa
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What distinguishes manipulative interpersonal influence from non-manipulative influence? When is it wrong to manipulate a person and what makes it wrong? I articulate a novel account according to which interpersonal manipulation is a process of influence that deliberately fails to track reasons. To manipulate a reasons-responsive person is to render her detached from an important aspect of reality, namely, her reasons or the considerations that ought to govern her behavior. This is what makes manipulation pro tanto morally impermissible (when it is). My account of manipulation provides a helpful framework for thinking through some of the philosophically neglected ethical issues arising out the application of social scientific research on human decision making in the domains of health care and public policy.

Adaptive Evolving Strategy for Dextrous Robotic Manipulation

Arismendi, César; Álvarez, David; Garrido, Santiago; Moreno Lorente, Luis Enrique
Fonte: Springer Publicador: Springer
Tipo: info:eu-repo/semantics/acceptedVersion; info:eu-repo/semantics/article
Publicado em /03/2014 ENG
Relevância na Pesquisa
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A robot task can be represented as a set of trajectories conformed by a sequence of poses. In this way it is possible to teach a mobile robot to accomplish a manipulation task, and also to reproduce it. Nevertheless robot navigation may normally introduce inaccuracies in localization due to natural events as wheel-slides, causing a mismatch between the end-effector and the objects or tools the robot is supposed to interact with. We propose an algorithm for adapting manipulation trajectories for different locations. The adaptation is achieved by optimizing in position, orientation and energy consumption. The approach is built over the basis of Evolution Strategies, and only uses forward kinematics permitting to avoid all the inconveniences that inverse kinematics imply, as well as convergence problems in singular kinematic configurations. Manipulation paths generated with this algorithm can achieve optimal performance, sometimes even improving original path smoothness. Experimental results are presented to verify the algorithm.; The research leading to these results has received funding from the RoboCity2030-II-CM project (S2009/DPI-1559), funded by Programas de Actividades I+D en la Comunidad de Madrid and cofunded by Structural Funds of the EU.

Probabilistic Learning of Human Manipulation of Objects towards Autonomous Robotic Grasping

Faria, Diego Resende
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Tese de Doutorado
ENG
Relevância na Pesquisa
36.68%
Nesta tese estuda-se a forma como os seres humanos manipulam objectos do quotidiano, modelando-os de forma probabilística. Os modelos probabilísticos são também utlizados para a representação das tarefas e dos movimentos, com o objectivo de dotar mãos robóticas com elevado grau de autonomia. Um modelo volumétrico probabilístico centrado no objecto é proposto para representar a sua forma a partir de exploração táctil. O mapa volumétrico do objecto é também útil para a fusão de dados multimodais, mapas da região de contacto e força táctil durante uma pega estável. Este modelo é refinado através da segmentação do volume em componentes, aproximadas por superquádricas, e sobrepondo os pontos de contactos tendo em conta o contexto da tarefa. Uma nova técnica para identificação de objectos através de exploração táctil de objectos é proposta. Diferentes pontos de contacto são associados a forma de um objecto através de modelos de misturas, permitindo a identificação de um objecto através de um conjunto de configurações base que a mão toma durante a exploração. Os seres humanos destacam-se quando se trata de tarefas de manipulação do quotidiano, sendo capaz de aprender novas habilidades ou adaptar-se a novos e complexos ambientes. Esta capacidade resulta de uma aprendizagem pessoal...

The effects of thoracic manipulation versus mobilization for chronic neck pain: a randomized controlled trial pilot study

Suvarnnato, T.; Puntumetakul, R.; Kaber, D.; Boucaut, R.; Boonphakob, Y.; Arayawichanon, P.; Chatchawan, U.
Fonte: The Society of Physical Therapy Science Publicador: The Society of Physical Therapy Science
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
36.62%
[Purpose] To investigate effects of thoracic manipulation versus mobilization on chronic neck pain. [Methods] Thirty-nine chronic neck pain subjects were randomly assigned to single level thoracic manipulation, single level thoracic mobilization, or a control group. The cervical range of motion (CROM) and pain ratings (using a visual analog scale: VAS) were measured before, immediately after and at a 24-hour follow-up. [Results] Thoracic manipulation significantly decreased VAS pain ratings and increased CROM in all directions in immediate and 24-hour follow-ups. The thoracic mobilization group significantly increased in CROM in most directions at immediate follow-up and right and left rotational directions at the 24-hour follow-up. Comparisons between groups revealed the CROM for the manipulation group to increase significantly more than for control subjects in most directions at immediate follow-up and flexion, left lateral flexion and left rotation at the 24-hour follow-up. The CROM for the thoracic mobilization group significantly increased in comparison to the control group in flexion at immediate follow-up and in flexion and left rotation at the 24-hour follow-up. [Conclusion] The study demonstrated reductions in VAS pain ratings and increases in CROM at immediate and 24-hour follow-ups from both single level thoracic spine manipulation and thoracic mobilization in chronic neck pain.; Thavatchai Suvarnnato...

Multi-sensor based segmentation of human manipulation tasks

Hendrich, Norman; Klimentjew, Denis; Zhang, Jianwei
Fonte: IEEE Publicador: IEEE
Tipo: info:eu-repo/semantics/acceptedVersion; info:eu-repo/semantics/conferenceObject Formato: application/pdf
Publicado em /10/2010 ENG
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In this paper we present an overview of a multisensor setup designed to record and analyse human in-hand manipulation - tasks consisting of several phases of finger motions following the initial grasp. During the experiments all of the hand, finger, and object positions are recorded, as are the contact forces applied to the manipulated objects. The use of instrumented sensing objects complements the data. The goal is to understand and extract a basic set of finger and hand movement patterns, which can then be combined to perform a complete manipulation task, and which can be transferred to control robotic hands. The segmentation of whole manipulation traces into several phases corresponding to individual basic patterns is the first step towards this goal. Initial analysis and segmentation of two typical manipulation tasks are presented, showing the advantages of the multi-modal analysis.; European Community's Seventh Framework Program; Proceedings of: 2010 IEEE Conference on Multisensor Fusion and Integration for Intelligent Systems (FMI), September 5-7, 2010, Salt Lake City, USA

Depreciation manipulation and its impact on firms' returns

Vadeikaite, Kristina
Fonte: NSBE - UNL Publicador: NSBE - UNL
Tipo: Dissertação de Mestrado
Publicado em /01/2010 ENG
Relevância na Pesquisa
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA – School of Business and Economics; Earnings management is typically achieved via discretionary accruals (such as depreciation). Dechow et al. (1996), Archibald (1972), and Peasnell et al. (2000) present results on the market reaction to depreciation manipulation that are inconsistent. They find either no reaction or a negative one. This study aims at settling this contradiction by using several different methods, in order to identify a possible manipulation, with a sample of S&P500 firms. Data suggests that firms are manipulating depreciation. Furthermore, an analysis of useful life of assets reveals that firms have been increasing it since the dot com bubble burst and that its value is larger in profitable firms. However, results of our event studies reveal that the market is not reacting to deprecation manipulation. Thus, it seems possible for firms to fool the markets via this specific manipulation.

Manipulación diestra en ambientes desconocidos : un modelo bio-inspirado; Dexterous manipulation in unknown environments : a bio-inspired model

Matuk Herrera, Rosana Isabel
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2008 SPA
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En la actualidad, la manipulación robótica diestra y autónoma en ambientes desconocidos aún nos eluye. Niños de pocos años pueden levantar y manipular objetos no familiares con mayor destreza que los robots actuales. En consecuencia, los investigadores en robótica coinciden cada vez más que ideas de la biología pueden resultar beneficiosas en el diseño de mejores modelos para los robots. En este trabajo de tesis se presentan un modelo de control y algoritmos para cada una de las fases de manipulación, que están fuertemente inspirados en estudios neurofisiológicos sobre manipulación diestra humana. El control de las fuerzas de presa y carga en cada fase es dirigido por señales que simulan las respuestas aferentes humanas durante un proceso de manipulación. El objetivo del modelo es manipular objetos desconocidos con estabilidad de la presa y comportamiento similar al humano. Se utilizaron elementos finitos para simular computacionalmente dos dedos opuestos que toman objetos desconocidos, y un dedo presionando objetos. Los dos componentes esenciales del modelo de control propuesto fueron simulados y testeados exitosamente: la estimación del coeficiente de fricción entre el objeto y los dedos, y la detección del deslizamiento incipiente.; At present...

Magnetic Manipulation and Assembly of Multi-component Particle Suspensions

Erb, Randall Morgan
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação Formato: 6383465 bytes; application/pdf
Publicado em //2009 EN_US
Relevância na Pesquisa
36.58%

This thesis will investigate previously unexplored concepts in magnetic manipulation including controlling the assembly of magnetic and nonmagnetic particles either in bulk fluid or near a substrate. Both uniform glass interfaces and substrates with magnetic microstructures are considered. The main goal of this work is to discuss new strategies for implementing magnetic assembly systems that are capable of exquisitely controlling the positions and orientations of single-component as well as multi-component particle suspensions, including both magnetic and non-magnetic particles. This work primarily focuses on controlling spherical particles; however, there are also several demonstrations of controlling anisotropically shaped particles, such as microrods and Janus colloids.

Throughout this work, both conventional magnetophoresis and inverse magnetophoresis techniques were employed, the latter relying on ferrofluid, i.e. a suspension of magnetic nanoparticles in a nonmagnetic carrier fluid, which provides a strong magnetic permeability in the surrounding fluid in order to manipulate effectively non-magnetic materials. In each system it was found that the dimensionless ratio between magnetic energy and thermal energy could be successfully used to describe the degree of control over the positions and orientations of the particles. One general conclusion drawn from this work is that the ferrofluid can be modeled with a bulk effective permeability for length scales on the order of 100 nm. This greatly reduces modeling requirements since ferrofluid is a complex collection of discrete nanoparticles...

Manipulation of elections by minimal coalitions

Connett, Christopher
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
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Social choice is the study of the issues arising when a population of individuals attempts to combine its views with the objective of determining a collective policy. Recent research in artificial intelligence raises concerns of articial intelligence agents applying computational resources to attack an election. If we think of voting as a way to combine honest preferences, it would be undesirable for some voters cast ballots that differ from their true preferences and achieve a better result for themselves at the expense of the general social welfare. Such an attack is called manipulation. The Gibbard-Satterthwaite theorem holds that all reasonable voting rules will admit a situation in which some voter achieves a better result for itself by misrepresenting its preferences. Bartholdi and Orlin showed that finding a beneficial manipulation under the single transferable vote rule is NP-Complete. Our work explores the practical dificulty of the coalitional manipulation problem. We computed the minimum sizes of successful manipulating coalitions, and compared this to theoretical results.

In-hand manipulation of children aged four and five-years-old: translation, rotation and shift movements, in Bloemfontein

Visser,Marieta; Nel,Mariette; de Vries,Juanne; Klopper,Erina; Olën,Kabi; van Coller,Johanette
Fonte: South African Journal of Occupational Therapy Publicador: South African Journal of Occupational Therapy
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2014 EN
Relevância na Pesquisa
36.65%
BACKGROUND AND AIM: Children are often referred to occupational therapy for deficits in hand function, specifically in-hand manipulation problems. There is however no standardised measurement instrument with age-related norms available that evaluates all in-hand manipulation components. The aim of the study was to describe the in-hand manipulation skills of a multicultural group of four- and five-year-old children in Bloemfontein. METHODS: A quantitative, descriptive study that included 98 four and 97 five-year-old English-speaking children was conducted. An observation checklist was compiled from non-standardised activities and standardised tests published in the literature to cover all aspects of in-hand manipulation. Video footage of each child performing the activities was used to score the checklists RESULTS: A total of 195 children participated in the study, with 98 (50.3%) in the four-year-old and 97 (49.7%) in the five-year-old groups. The following percentages of four-year-old children had successful task completion (without compensation): finger-to-palm translation 11.2%, simple rotation 29.6%, complex rotation 44.9%, complex rotation with stabilisation 13.3% and shift movements 68.4%. The following percentages of five-year-olds had successful completion (without compensation): finger-to-palm translation 22.7%...