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991.
Currently, the development of leading‐edge technology for recording and loading human motion on the basis of haptic information is required in the fields of manufacturing and human support. Human movement is an assembly of motion components. Since human movements should be supported by a robot in real time, it is necessary to integrate the motion components that were saved earlier. Once such motion integration is realized, future technology for use in daily human life can be developed. This paper proposes the integrated reproduction of the decomposed components of human motion by using a motion copying system. This system is the key technology for the realization of the acquisition, saving, and reproduction of real‐world haptic information. By using the proposed method, it is possible not only to achieve expert skill acquisition, skill transfer to robots, and power assist for each motion component, but also to open up new areas of applications. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 181(1): 28–35, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21263 相似文献
992.
Gavriel Salvendy 《Theoretical Issues in Ergonomics Science》2013,14(2):169-178
Stages in the development of the classification for human motions are reviewed from the 17th century up to the present day, with special emphasis on the discrete events approach to the classification of human motions as advocated by the Gilbreths. It is put forward that this approach is inappropriate both from the psychological and the physiological view point; while at the same time it is emphasized that, although the therblig approach contributed significantly to the understanding of human motions and skills, nevertheless it may be more harmful than beneficial in the long run. The additive properties of the discrete events approach to the analysis of human motions are considered. Results of the investigations reported here suggest that, in the performance of repetitive tasks of the nature described here, the therblig times of the task are independent units within a work cycle, when analysed by means of 100 cycles. Thus, the times are additive in the mathematical sense, but when the same task is repeated only once, or a very few times, and analysed by single cycles, the therblig times form an integrated part of the entire work cycle and, therefore, their times are not additive in the mathematical sense. 相似文献
993.
Paola Songia Mattia Chiesa Valentina Alfieri Ilaria Massaiu Donato Moschetta Veronika Myasoedova Vincenza Valerio Laura Fusini Paola Gripari Marco Zanobini Paolo Poggio 《International journal of molecular sciences》2021,22(4)
Mitral valve prolapse (MVP) associated with severe mitral regurgitation is a debilitating disease with no pharmacological therapies available. MicroRNAs (miRNA) represent an emerging class of circulating biomarkers that have never been evaluated in MVP human plasma. Our aim was to identify a possible miRNA signature that is able to discriminate MVP patients from healthy subjects (CTRL) and to shed light on the putative altered molecular pathways in MVP. We evaluated a plasma miRNA profile using Human MicroRNA Card A followed by real-time PCR validations. In addition, to assess the discriminative power of selected miRNAs, we implemented a machine learning analysis. MiRNA profiling and validations revealed that miR-140-3p, 150-5p, 210-3p, 451a, and 487a-3p were significantly upregulated in MVP, while miR-223-3p, 323a-3p, 340-5p, and 361-5p were significantly downregulated in MVP compared to CTRL (p ≤ 0.01). Functional analysis identified several biological processes possible linked to MVP. In addition, machine learning analysis correctly classified MVP patients from CTRL with high accuracy (0.93) and an area under the receiving operator characteristic curve (AUC) of 0.97. To the best of our knowledge, this is the first study performed on human plasma, showing a strong association between miRNAs and MVP. Thus, a circulating molecular signature could be used as a first-line, fast, and cheap screening tool for MVP identification. 相似文献
994.
995.
Maryam Saeidifar A. Khanlarkhani M. Eslami-Moghaddam Hassan Mansouri-Torshizi Ali Akbar Saboury 《Polycyclic Aromatic Compounds》2016,36(1):40-57
The interaction of 1, 10-phenanthroline octhyldithiocarbamato palladium(II) nitrate ([Pd(Oct-dtc)(phen)]NO3) with human serum albumin (HSA) has been investigated by various spectroscopic techniques under physiological conditions. Here, HSA was titrated with the Pd(II) complex, followed by UV–Vis absorption spectroscopy to estimate a binding constant (Kb) and other thermodynamic parameters. The results indicate that the Pd (II) complex has a high affinity for bind HSA. Thermodynamic analysis showed that the enthalpy (ΔH°) and entropy changes (ΔS°) are positive and Gibbs free energy change (ΔG°) is negative which indicated that hydrophobic interactions played the predominant role in the binding process. Fluorescence spectroscopy were used to show the mechanism and binding parameters of this interaction. Utilizing the Stern–Volmer equation, the Pd(II) complex quenched the intrinsic fluorescence of HSA via a static quenching procedure. The specific binding distances between the tryptophan (donor) proteins and Pd(II) complex (acceptor) were estimated by Forster resonance energy transfer. The CD results also showed the conformational changes on serum albumin upon binding with the Pd(II) complex. 相似文献
996.
E-commerce customers demand quick and easy access to products in large search spaces according to their needs and preferences. To support and facilitate this process, recommender systems (RS) based on user preferences have recently played a key role. However the elicitation of customers preferences is not always precise either correct, because of external factors such as human errors, uncertainty and vagueness proper of human beings and so on. Such a problem in RS is known as natural noise and can bias customers recommendations. Despite different proposals have been presented to deal with natural noise in RS none of them is able to manage properly the inherent uncertainty and vagueness of customers preferences. Hence, this paper is devoted to a new fuzzy method for managing in a flexible and adaptable way such uncertainty of natural noise in order to improve recommendation accuracy. Eventually a case study is performed to show the improvements produced by this fuzzy method regarding previous proposals. 相似文献
997.
《Ergonomics》2012,55(2):265-272
A ball-catching task in which the ball was caused to enter on a parabolic flight path by means of a mechanical apparatus was administered to 36 male students between the ages of 18 and 40 years. An electronic device enabled the ball to be illuminated for predetermined temporal intervals during its flight. Results indicated that in this relatively unpredictable task opportunity to watch the ball for longer periods of time resulted in increased catching success. Results are discussed in relation to previous experimental work in which the ball was on a more predictable trajectory (since output information was available) and are related to the perceptual moment hypothesis. 相似文献
998.
《Behaviour & Information Technology》2012,31(9):902-919
The fast aging of many western and eastern societies and their increasing reliance on information technology create a compelling need to reconsider older users' interactions with computers. Changes in perceptual and motor skill abilities that often accompany the aging process have important implications for the design of information input devices. This paper summarises the results of two comparative studies on information input with 90 subjects aged between 20 and 75 years. In the first study, three input devices – mouse, touch screen and eye-gaze control – were analysed concerning efficiency, effectiveness and subjective task difficulty with respect to the age group of the computer user. In the second study, an age-differentiated analysis of hybrid user interfaces for input confirmation was conducted combining eye-gaze control with additional input devices. Input confirmation was done with the space bar of a PC keyboard, speech input or a foot pedal. The results of the first study show that regardless of participants' age group, the best performance in terms of short execution time results from touch screen information input. This effect is even more pronounced for the elderly. Regarding the hybrid interfaces, the lowest mean execution time, error rate and task difficulty were found for the combination of eye-gaze control with the space bar. In conclusion, we recommend using direct input devices, particularly a touch screen, for the elderly. For user groups with severe motor impairments, we suggest eye-gaze information input. 相似文献
999.
A total of 286 lactic acid bacteria isolated from goat’s dairy products in northwest of Argentina were characterized. Lactobacilli (38%) and cocci (62%) were identified according to morphological, physiological, and relevant technological properties. L. plantarum (14%) and Enterococcus (34%) were the predominant species. S. thermophilus, Pediococcus and L. plantarum were the highest acid producers. Eight strains of L. fermentum produced bacteriocins or metabolites similar to bacteriocins. The API-ZYM test was applied to 39 isolates. Eight strains were selected from their both technological properties and enzymatic activities for use as starter or adjunct culture in the manufacture of artisanal goat cheeses. 相似文献
1000.
Siegfried Bolenz Josefine Römisch Thorsten Wenker 《International Journal of Food Science & Technology》2014,49(7):1644-1653
Chocolate mass of low viscosity is preferred for most applications. Milk powder influences processing behaviour, flow properties and taste of milk chocolate. The project aimed to investigate influences of skim milk powders containing amorphous or crystalline lactose on flow properties after producing samples by roller milling and conching or alternatively by ball milling. For the first case, it was found that mass consistency before roller milling is strongly influenced by lactose type; producers must specify it and adapt initial mass fat content. Little impact on final products was found after processing milk powders at equilibrium moisture. If predried powders are used for reducing conching time, crystalline lactose leads to chocolate with slightly lower viscosity. At ball mill processing, crystalline lactose resulted in significantly lower viscosity, for example 15% at 40 s?1; thus, for this process, it can be recommended to use special milk powders high in crystalline lactose content. 相似文献