493 research outputs found
Robust safety zones for manipulators with uncertain dynamics in collaborative robotics
In this paper, an approach for computing online safety zones for collaborative robotics in a robust way, despite uncertain robot dynamics, is proposed. The strategy implements the speed and separation monitoring paradigm, and considers human and robot enclosed in bounding volumes. The human-robot collaboration is monitored by a supervisory controller that guides the robot to stop along a path-consistent trajectory in case of collision danger between human and robot. The size of the robot safety zone is minimized online according to the stop time of the manipulator, and the uncertain robot dynamics is considered using interval arithmetic to ensure compliance with the joint torques limits even in case of imperfect knowledge of the dynamic model parameters. The results verify the effectiveness of the proposed approach, and evaluate the influence of dynamics variations on human-robot collaboration
Eficiência e viabilidade econômica da aplicação de fungicidas no controle da ferrugem asiática da soja em Campo Grande, MS.
Objetivou-se avaliar a eficiência e a viabilidade econômica da aplicação de fungicidas no controle da ferrugem asiática da soja, Phakopsora packyrhizi, em Campo Grande, MS. O ensaio foi conduzido em na safra 2007-2008. Foram avaliados os fungicidas (g i.a./ha): picoxistrobina + ciproconazole (40 + 16, 50 + 20 e 60 + 24) + nimbus 0,25% (v/v), piraclostrobina + epoxiconazole (66,5 + 25); azoxistrobina + ciproconazole (60 + 24) + nimbus 0,25% (v/v); trifloxistrobina + tebuconazole (50 + 100) + auero 0,13% (v/v) e trifloxistrobina + ciproconazole (56,25 + 24) + aureo 0,13% (v/v). Três aplicações foram realizadas, quinzenalmente, a partir do estádio fenológico R2. Foram realizadas 10 avaliações da severidade da doença (terços inferior e superior da planta) e três da desfolha (a partir do estádio R7), com intervalos de sete dias. Após plotagem das curvas de progresso (CP), foram calculadas as áreas abaixo das CP para a severidade da doença (AACPD) e desfolha (AACPDes). Ao final do ensaio, avaliou-se o rendimento de grãos (Rend - kg/ha), a massa de 1.000 grãos (MMG - g) e a viabilidade econômica do controle da doença. O clima durante a condução do ensaio foi favorável ao desenvolvimento da ferrugem asiática, constatando-se relação positiva entre a precipitação e a severidade da doença. Todos os fungicidas apresentaram valores de AACPD inferiores ao da testemunha, com destaque para picoxistrobina + ciproconazole (maior dose). Esse tratamento também apresentou o menor índice de AACPDes. Os fungicidas apresentaram índices semelhantes de Rend, embora superiores à testemunha. Quanto a MMG, maior índice foi atribuído a azoxistrobina + ciproconazole. A mistura trifloxistrobina + tebuconazole apresentou a menor eficiência de controle da ferrugem asiática. Com base na severidade da doença, rendimento de grãos e nos benefícios econômico gerados pela aplicação de fungicidas, identificou-se os fungicidas picoxistrobina + ciproconazole (60 + 24), azoxistrobina + ciproconazole e trifloxistrobina + ciproconazole como os mais promissores para o controle de P. packyrhizi
Microestrutura da fibra alimentar do albedo de laranja: um estudo por técnicas físicas e análise de imagens.
As fibras alimentares são consumidas naturalmente em cereais, frutas e hortaliças, mas também são adicionadas na forma concentrada em alimentos processados. Diferentes fontes de fibras têm diferentes estruturas e composições químicas, que irão definir a sua finalidade nutricional ou tecnológica. Este trabalho tem como objetivo a caracterização de fibra alimentar do albedo da laranja submetida a dois métodos de secagem (liofilização e convencional) e divididas por intervalos granulométricos. Para as determinações de densidade, área superficial, porosidade e distribuição de tamanho de poro, utilizaram-se técnicas clássicas da tecnologia de sistema particulado e foram comparadas com imagens de microscopia eletrônica de varredura. Os resultados apontaram que o método de secagem é o que mais influenciou na redução do volume de poros do material, também visualizado nas características microestruturais reveladas pela análise de imagem. O intervalo granulométrico da fibra particulada apresentou-se inversamente proporcional à densidade e à área superficial específica do material. A fibra alimentar do albedo da laranja apresentou características estruturais que permitem a diversificação de novos produtos alimentícios com alto valor nutritivo e comercial
Lenalidomide before and after Autologous Hematopoietic Stem Cell Transplantation in Multiple Myeloma
Although multiple myeloma remains incurable outside of allogeneic hematopoietic stem cell transplantation, novel agents made available only in the last few decades have nonetheless tremendously improved the landscape of myeloma treatment. Lenalidomide, of the immunomodulatory class of drugs, is one of those novel agents. In the non-transplant and relapsed/refractory settings, lenalidomide clearly benefits patients in terms of virtually all meaningful outcomes including overall survival. Data supporting the usage of lenalidomide as part of treatment approaches incorporating high-dose chemotherapy with autologous stem cell support (ASCT) are less mature as pertains to such long-term outcomes and toxicity, and lenalidomide is not currently approved by regulatory agencies for use in the context of ASCT in either the United States or Europe. That said, relatively preliminary efficacy data describing lenalidomide as a component of ASCT-based treatment approaches to MM are indeed promising, and consequently lenalidomide's role in ASCT-based treatment strategies is growing. In this review we summarize existing data that pertains to lenalidomide in the specific context of ASCT, and we share our thoughts on how our own group applies these data to approach this complex issue clinically
Computer Simulation and Fire Drill in an Educational Building
Despite the evolution of computational models for evacuation simulations, there's still some doubt if they can generate accurate results. The objective is to analyze and compare the evacuation times of a fire drill and a computer simulation in an educational building. The method consisted of a fire drill with prior notice of a 4-floor building with classrooms in a public university. A computational model was developed for the same building and population using the evacuation simulation software Pathfinder. The results were that the evacuation times observed in the computer simulation were slightly lower than the times of the fire drill because people covered smaller distances due to the random distribution performed by the Pathfinder software and because in the drill some time was spent for the start of the movement toward the exit, which was estimated at around 30 seconds, while the software was configured for a pre-movement time equal to zero. The use of the computer simulation, therefore, proved to be an effective solution to replace the fire drill, since it allows for the identification of design failures and for the simulation of different scenarios in less time and without the need to mobilize people
Field‐based validation of penalty shooting recommendations: An experiment with elite youth football players
Research has suggested many ways in which professional football players can increase their penalty shooting success rate. We set up a field experiment testing these recommendations. We perform the experiment with one of the most successful youth academies in the world. All players are highly skilled, including prospective and current Brazilian youth national players. The players either decide themselves where to shoot or the coach tells them where to shoot. The coach does not reveal if the decision is based on a random allocation or his own choice. The algorithm randomly selects where players must shoot. The results from the experiment show that the best outcome is when players choose where they want to shoot. Coaches and random algorithm have a lower success rate, although following research‐based recommendations. The findings are important as they show that researchers should test their recommendations in the field as they do not necessarily translate into real‐life settings
When a woman replaces a man: evaluating coach dismissal in professional tennis
Purpose
Previous research indicates gender discrimination in leadership positions. However, performance and not gender should be the key indicator when evaluating a leader. We examine the performance effect of changing from a female to a male coach and vice versa.
Methodology
We analyze 1,093 Billie Jean King Cup singles matches from 2006 to 2016, with the match result as the dependent variable. First, we examine the very short-term effects arising from the change of a coach with a regression discontinuity design. Second, we evaluate the short-, medium-, and long-term performances.
Findings
The results show that the gender of the new coach has no significant effect on performance. However, when a female coach succeeds another female coach, performance improves. This provides an argument in favor of female leadership.
Practical Implications
Team managers should primarily focus on the quality of the coach instead of gender. The results also suggest that a continuum of female leadership is likely advantageous.
Research Contribution
This paper contributes to the debate regarding the misrepresentation of women as head coaches and offers an avenue for further research
Non-myeloablative allogeneic transplantation with alemtuzumab, fludarabine and cyclophosphamide using 3-6/6 HLA matched donors
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