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The paper presents preliminary results on the research methodology of evaluating the ergonomic properties of gloves protecting against cuts and stabs by hand knives. Four manual dexterity tests were selected for the study: TEST 1: evaluation of fine finger movements pursuant to PN-EN 420; TEST 2: cylinder grip and pull test according to PN-EN 1082 evaluating gross movements of the arms and hands; TEST 3: Purdue Pegboard Test evaluating fine finger movements; TEST 4: evaluation of gross movements of the arms and hands while performing simulated occupational tasks. The tested gloves differed in terms of construction and material (metal mesh or knitwear incorporating a metal yarn) and were selected depending on the scope of work activities performed during meat cutting and boning. The tests were conducted on a homogeneous group of subjects. During the performance of the four dexterity tests, we monitored the loading of four groups of muscles of the upper limb (adductor pollicis, extensor carpi radialis, flexor carpi ulnaris, and biceps brachii) using surface electromyography (EMG). Additionally, subjective sensations concerning the strain on the upper limb were evaluated using a questionnaire survey.The objective of the study was to identify a group of tests that would be characterized by high sensitivity and ensure reliable assessment of gloves protecting against cuts and stabs by hand knives. The results showed that not all of the dexterity captured differences in the way the gloves affected dexterity. This was corroborated by electromyographic measurements, which revealed considerable differences in load of upper limb muscles when using various gloves and further supported by the subjective sensations of the participants, as reported in the questionnaire study. It was concluded that in order to reliably evaluate the ergonomic properties of gloves protecting against cuts and stabs by hand knives it is necessary to design new dexterity tests that would reflect actual workplace conditions, and could simulate occupational activities. Workplace observations helped to identify specific aspects of manual dexterity (fine, medium, gross), and types of hand movement associated with professional activities including different force configurations (finger flexion, wrist abduction, and pressing with the fingers and wrist). Based on those observations three new manual dexterity tests dedicated exclusively to evaluation of the ergonomic properties of gloves protecting against cuts and stabs by hand knives have been proposed.  相似文献   
74.
Social play is an increasingly important constituent of the digital game experience. Though there is a growing understanding of how the social context influences the experience of playing, there is little known about how the experience of play influences the social experience. Specifically, it is not even known whether winning or losing affects a player's sense of social presence with their co-players. This paper provides the results of two studies aiming to explore this interaction. The first study is a lab-based study that looked at whether social presence varied in collocated teams playing team-based games depending on whether they won or lost. The second study is a user experience survey which measured how variables in the context of gameplay affected social presence across a number of team-based online games. The results of both studies show that when teams lose, the negative impact on social presence is greater within teams than between the competing teams. This has implications for how studies in this area should be analysed and also, through consideration of individual games, suggests that mechanisms in the games may lead to the reduced social presence.  相似文献   
75.
Problematic smartphone use is an important public health challenge and is linked with poor mental health outcomes. However, little is known about the mechanisms that maintain this behavior. We recruited a sample of 308 participants from Amazon’s Mechanical Turk labor market. Participants responded to standardized measures of problematic smartphone use, and frequency of smartphone use, depression and anxiety and possible mechanisms including behavioral activation, need for touch, fear of missing out (FoMO), and emotion regulation. Problematic smartphone use was most correlated with anxiety, need for touch and FoMO. The frequency of use was most correlated (inversely) with depression. In regression models, problematic smartphone use was associated with FoMO, depression (inversely), anxiety, and need for touch. Frequency of use was associated with need for touch, and (inversely) with depressive symptoms. Behavioral activation mediated associations between smartphone use (both problematic and usage frequency) and depression and anxiety symptoms. Emotional suppression also mediated the association between problematic smartphone use and anxiety. Results demonstrate the importance of social and tactile need fulfillment variables such as FoMO and need for touch as critical mechanisms that can explain problematic smartphone use and its association with depression and anxiety.  相似文献   
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77.
《Computer Networks》2008,52(6):1125-1141
In the context of multimedia and real-time systems, this article introduces a generic interpreter of QoS properties (xQoS-Interpreter) for the Application Data Units (ADUs) composing standard and proprietary multimedia streams. This approach is intended to make the QoS properties of ADUs publicly available to any mechanism of the underlying communication system. The use of this information allows for cross-layer QoS optimization of the communication services taking the actual per-packet requirements of the applications into account. A case study showing how the xQoS-Interpreter is used at transport layer to seamlessly optimize the perceived QoS of an end-to-end video transmission is presented. In this scenario, the xQoS-Interpreter is used to optimize a TCP-friendly Rate Control mechanism (TFRC) over congested wireless network services in order to demonstrate the feasibility and advantages of our approach.  相似文献   
78.
The introduction of sit-stand worktables was examined in this study. Purchasers at four companies were interviewed regarding preparations prior to purchase, follow-up after installation, and if expectations had been fulfilled. Personnel at the four companies answered a questionnaire examining use of the worktables' sit-stand function, and the influence of some variables on this. Utilisation of the sit-stand function was less than what could be expected to relieve static musculoskeletal loading during VDU work. Pain experienced during the past year, and education on the use of the worktable gave rise to modest increases in utilisation. Investment in sit-stand worktables was satisfactory to purchasers, in terms of providing flexible furniture to suit modern organisational dynamics. Users were, in general, positive to the worktables, but showed poor compliance in using them. User and purchaser satisfaction with regard to improving individual health ergonomics was questionable in respect of the low level of usage.  相似文献   
79.
SUMMARY

An inexpensive gas chromatographic integrator with digital readout is described. The device is precise to ±1 count and shows linear response to within ±2%. It is directly compatible with flame ionization detectors and is easily adapted to thermal conductivity detectors.  相似文献   
80.
In practice, classifiers in an ensemble are not independent. This paper is the continuation of our previous work on ensemble subset selection [A. Ula?, M. Semerci, O.T. Y?ld?z, E. Alpayd?n, Incremental construction of classifier and discriminant ensembles, Information Sciences, 179 (9) (2009) 1298–1318] and has two parts: first, we investigate the effect of four factors on correlation: (i) algorithms used for training, (ii) hyperparameters of the algorithms, (iii) resampled training sets, (iv) input feature subsets. Simulations using 14 classifiers on 38 data sets indicate that hyperparameters and overlapping training sets have higher effect on positive correlation than features and algorithms. Second, we propose postprocessing before fusing using principal component analysis (PCA) to form uncorrelated eigenclassifiers from a set of correlated experts. Combining the information from all classifiers may be better than subset selection where some base classifiers are pruned before combination, because using all allows redundancy.  相似文献   
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