Reactive synthesis is a class of methods to construct a provably-correct control system, referred to as a robot, with respect to a temporal logic specification in the presence of a dynamic and uncontrollable environme...
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The classification of visual human action is important in the development of systems that interact with humans. This study investigates an image-based classifica- tion of the human state while using a walking support ...
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The classification of visual human action is important in the development of systems that interact with humans. This study investigates an image-based classifica- tion of the human state while using a walking support system to improve the safety and dependability of these systems. We categorize the possible human behavior while utilizing a walker robot into eight states (i.e., sitting, standing, walking, and five falling types), and propose two different methods, namely, normal distribution and hidden Markov models (HMMs), to detect and recognize these states. The visual feature for the state classification is the centroid position of the upper body, which is extracted from the user's depth images. The first method shows that the centroid position follows a normal distribution while walking, which can be adopted to detect any non-walking state. The second method implements HMMs to detect and recognize these states. We then measure and compare the performance of both methods. The classification results are employed to control the motion of a passive-type walker (called "RT Walker") by activating its brakes in nonwalking states. Thus, the system can be used for sit/stand support and fall prevention. The experiments are performed with four subjects, including an experienced physiotherapist. Results show that the algorithm can be adapted to the new user's motion pattern within 40 s, with a fall detection rate of 96.25% and state classification rate of 81.0%. The proposed method can be implemented to other abnormality detection/classification applications that employ depth image-sensing devices.
Interfacial asymmetry in conjunction with strain engineering can provide an alternate pathway to achieve efficient and controllable spin to charge conversion. This hypothesis is experimentally verified using spin-Seeb...
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This paper introduces the PettingZoo library and the accompanying Agent Environment Cycle ("AEC") games model. PettingZoo is a library of diverse sets of multi-agent environments with a universal, elegant Py...
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Energy is a systematic problem involving many fields and disciplines. Discourse about it requires systems thinking. This research aims to reveal trends and future work related to system thinking on renewable energy. T...
Energy is a systematic problem involving many fields and disciplines. Discourse about it requires systems thinking. This research aims to reveal trends and future work related to system thinking on renewable energy. The method used is a bibliometric analysis of the Scopus database using VOSviewer software. Through the selection process, 284 documents deemed relevant were selected from journal articles and conference proceedings. Through VOSviewer analysis, 4 clusters of related keyword groups are shown. Four very influential words in this research theme are systems theory with 224 occurrences, renewable energy resources with 142 occurrences, renewable energy with 112 occurrences, and system dynamics with 102 occurrences. Through network visualization, the relationship between concepts both within one cluster and between clusters is shown. The visualization overlays is used as a basis of mapping the future work related to system thinking on renewable energy which include renewable energy resources, system theory, system dynamics, alternative energy, sustainable development, decision making, and renewable energy technology. This study concludes that bibliometric analysis through VOSviewer is proven to be able to show trends and future work for systems thinking on renewable energy research.
It was not sufficient to merely establish the amount of wear on friction surfaces in brake mechanisms for a certain period of time. The principal objective is to determine the intensity of wear on the friction mating ...
It was not sufficient to merely establish the amount of wear on friction surfaces in brake mechanisms for a certain period of time. The principal objective is to determine the intensity of wear on the friction mating surfaces in general, as this will enable us to evaluate the reliability of the braking systems in passenger vehicles under operating conditions. The main purpose of the paper is to substantiate a methodology for assessing the wear intensity in frictional interfaces specifically for disc brakes that are installed in passenger vehicles. The primary objectives of the research work were identified. Conducted, accordingly, is the analysis to determine the extent to which various parameters for braking vehicles influence the wear on friction surfaces in disc brakes. Our substantiation is based on observed patterns of friction surfaces wear for disc brake mechanisms. A mathematical method was developed for estimating the intensity of wear on friction surfaces in disc brake mechanisms. Devised, additionally, was a technique for experimental research involving cyclic emergency braking of a vehicle on a dry horizontal asphalt concrete road. An analytical-graphical method was adopted to simulate the wear process on the friction surfaces of disc brakes for such passenger vehicles as: Daewoo Lanos, Lada Priora, Chevrolet Aveo and Forza. Each braking cycle consists of 30 emergency braking sequences, with initial braking speeds ranging from 10 to 35 m / s. The vehicle used was fully loaded and the aerodynamic force of air resistance was taken into account. The wear intensity of the friction interface during the braking cycle was evaluated by a special criterion. This criterion was calculated as the average sum of the friction interface wear ratios (as the difference between the disc and the friction lining wear) and the corresponding braking distance at which the wear occurred. For clarity, all measurement results were presented in both graphical and tabular formats.
In today's world sales and demand for products has grown exponentially. There is always a need of the products in a huge count in terms of production, handling of such a huge count of products is not possible with...
In today's world sales and demand for products has grown exponentially. There is always a need of the products in a huge count in terms of production, handling of such a huge count of products is not possible without automation process but the instruments used of such automation process is of high cost which is not feasible for the small scale industries to implement such a high-cost machine for their use cases. To overcome the above problem of handling the products, a low-cost pick and place robot has been designed for handling the products, this robot is designed based on RRT:R configuration for the robot body, with this configuration this robot can handle products in complex positions. This robot is featured with the six DOF (degrees of freedom) for its movement. This robot is a tele-operated robot that can be controlled using a specialized mobile application developed using MIT APP INVENTOR 2 which makes the user use this robot without any special support for controlling, this robot gives a hassle-free experience for the user who is controlling the robot. By using this robot pick and place tasks can be simplified and the process can be automated and the rate of product handling can be increased.
In a non-majors upper-level undergraduate environmental history course focused on the Laurentian Great Lakes, students researched and wrote micro-histories of the Rochester, NY area. Many were focused on water-quantit...
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In a non-majors upper-level undergraduate environmental history course focused on the Laurentian Great Lakes, students researched and wrote micro-histories of the Rochester, NY area. Many were focused on water-quantity, quality, recreation, and pollution. This article briefly explains the approach and its potential applications to other interdisciplinary water courses. Then five of the original micro-water history cases are presented. It concludes with the lessons learned as a class and for teaching local water history in the future incorporating the previous class' findings.
Gait abnormalities introduce undesired patterns that limit stability, efficiency, and finally, walker independence. Most of the current algorithms for the identification of gait events using kinematic and inertial dat...
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ISBN:
(数字)9781728159072
ISBN:
(纸本)9781728159089
Gait abnormalities introduce undesired patterns that limit stability, efficiency, and finally, walker independence. Most of the current algorithms for the identification of gait events using kinematic and inertial data have obtained high performance in healthy subjects. However, most of them showed limited performance when tested with impaired subjects. We hypothesize that to improve gait event detection one must take into consideration the differences between the dynamics of each phase. In this paper, we developed and evaluated a novel methodology for adaptation of a set of parameters for gait event detection using mechanical perturbations. Our proposal employs an ensemble-based procedure for the characterization of the ankle dynamics. We based our proposal on a hybrid model of the human dynamics during gait where the parameters of the dynamics model are abruptly changed according to a Markov chain. In this document, we described the adaptive algorithm and presented preliminary results on a gait simulator. We demonstrated the ability of the algorithm to adapt the parameters according to the changes in human walking.
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