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81.
This study examined the effects of wrist rest and forearm support on reducing computer operators' activities using the trapezius, deltoid, biceps brachii, extensor carpi radialis longus, and extensor digitorum. 12 young (M= 25.9 yr., SD= 2.4) men were asked to perform both static and dynamic mouse operations in four conditions, two using a wrist rest and two using a forearm support. Analysis showed that use of the forearm support had a significant effect on reducing the EMG activity in muscles of the trapezius, deltoid, biceps brachii, extensor carpi radialis longus, and extensor digitorum. However, the wrist rest only significantly reduced deltoid and extensor carpi radialis longus activities. 相似文献
82.
How do humans use target-predictive contextual information to facilitate visual search? How are consistently paired scenic objects and positions learned and used to more efficiently guide search in familiar scenes? For example, humans can learn that a certain combination of objects may define a context for a kitchen and trigger a more efficient search for a typical object, such as a sink, in that context. The ARTSCENE Search model is developed to illustrate the neural mechanisms of such memory-based context learning and guidance and to explain challenging behavioral data on positive-negative, spatial-object, and local-distant cueing effects during visual search, as well as related neuroanatomical, neurophysiological, and neuroimaging data. The model proposes how global scene layout at a first glance rapidly forms a hypothesis about the target location. This hypothesis is then incrementally refined as a scene is scanned with saccadic eye movements. The model simulates the interactive dynamics of object and spatial contextual cueing and attention in the cortical What and Where streams starting from early visual areas through medial temporal lobe to prefrontal cortex. After learning, model dorsolateral prefrontal cortex (area 46) primes possible target locations in posterior parietal cortex based on goal-modulated percepts of spatial scene gist that are represented in parahippocampal cortex. Model ventral prefrontal cortex (area 47/12) primes possible target identities in inferior temporal cortex based on the history of viewed objects represented in perirhinal cortex. 相似文献
83.
Y. Z. Liu X. T. Zu J. Lian L. Wang X. Q. Huang Z. G. Wang 《Philosophical Magazine Letters》2013,93(11):705-712
Ti–Al–Zr alloy has been oxidized at 360°C in alkaline steam at a pressure of 10.3?±?0.7?MPa. Cross-sectional transmission electron microscopy (TEM) observations indicated that the oxide scale of Ti–Al–Zr alloy was composed of outer and inner subscales, in which the outer layer consists of anatase-TiO2 and the inner layer a mixture of TiO and Ti2O. The thickness of the Ti2O, TiO and anatase-TiO2 were approximately 50, 100 and 400?nm, respectively. These results were confirmed by X-ray energy dispersive spectrometry (EDS) measurements. The enhanced corrosion of titanium alloys in LiOH solution is attributed to a high hexagonal Ti2O to tetragonal TiO2 phase transformation rate induced by the substitution of Li+ for Ti4+ in the oxide layer. 相似文献
84.
Piracy is the greatest threat facing the global music industry today. This study explores the effects of artist adoration and the perceived risk of being caught on the attitude and intention to engage in pirating a digital song among college students. The moderating effect of cultural environment factor is also examined. Experiments using between-group factorial designs were conducted in the United States and Taiwan. The results show that perceived risk of getting caught and cultural environment are important factors that can significantly affect the attitude and intention toward downloading unauthorized music. In addition, a two-way (Perceived Risk × Culture) and a three-way interaction in the model are also observed. 相似文献
85.
Junwei Huang Lehua Cheng Jing Zhu 《The International journal for the psychology of religion》2013,23(1):29-41
Jesse Bering (2002) investigated how American university students in an interview task conceived of dead persons' mentality immediately after death. He found that different categories of mental states or capacities were conceived differently: psychobiological and perceptual states ceased, whereas emotional, desire, and epistemic states continued. Our Study 1 was a replication of Bering's experiment in a different cultural setting, in which the subjects were Chinese undergraduate students. A similar pattern of results was found. In Study 2, instead of being asked about a dead person's various mental states immediately following the death, participants were asked to judge a dead person's mental states after the person had been dead for 2 days. The overall pattern of participants' responses was not affected by this manipulation, but they did show an increase in attributions of certain mental states to dead agnostics. In addition, a more refined breakdown of responses revealed that individuals tended to judge that, upon death, visual and auditory perception continued, whereas olfactory and gustatory sensation ceased. 相似文献
86.
This study investigated how frequency demand and motion feedback influenced composite ocular movements and eye-hand synergy during manual tracking. Fourteen volunteers conducted slow and fast force-tracking in which targets were displayed in either line-mode or wave-mode to guide manual tracking with target movement of direct position or velocity nature. The results showed that eye-hand synergy was a selective response of spatiotemporal coupling conditional on target rate and feedback mode. Slow and line-mode tracking exhibited stronger eye-hand coupling than fast and wave-mode tracking. Both eye movement and manual action led the target signal during fast-tracking, while the latency of ocular navigation during slow-tracking depended on the feedback mode. Slow-tracking resulted in more saccadic responses and larger pursuit gains than fast-tracking. Line-mode tracking led to larger pursuit gains but fewer and shorter gaze fixations than wave-mode tracking. During slow-tracking, incidences of saccade and gaze fixation fluctuated across a target cycle, peaking at velocity maximum and the maximal curvature of target displacement, respectively. For line-mode tracking, the incidence of smooth pursuit was phase-dependent, peaking at velocity maximum as well. Manual behavior of slow or line-mode tracking was better predicted by composite eye movements than that of fast or wave-mode tracking. In conclusion, manual tracking relied on versatile visual strategies to perceive target movements of different kinematic properties, which suggested a flexible coordinative control for the ocular and manual sensorimotor systems. 相似文献
87.
This study examines the dynamic regulation process responding to an external stimulus. The damped oscillator model has been used to describe this process. However, the model does not allow a nonzero steady state, even though the oscillations may continue and do not necessarily damp toward zero. This study introduces the driven damped oscillator model which has an additional parameter to identify different patterns of the steady state. Three methods, generalized local linear approximation, continuous time structural equation modeling, and analytic solutions of differential equations are provided to estimate model parameters. A simulation study indicates that parameters in the driven damped oscillator model are well recovered. The model is then illustrated using a data set on the daily reports of sales after a sale promotion. Potential applications and possible expansions of this model are also discussed. 相似文献
88.
This study investigated the sensitivity of common fit indices (i.e., RMSEA, CFI, TLI, SRMR-W, and SRMR-B) for detecting misspecified multilevel SEMs. The design factors for the Monte Carlo study were numbers of groups in between-group models (100, 150, and 300), group size (10, 20, 30, and 60), intra-class correlation (low, medium, and high), and the types of model misspecification (Simple and Complex). The simulation results showed that CFI, TLI, and RMSEA could only identify the misspecification in the within-group model. Additionally, CFI, TLI, and RMSEA were more sensitive to misspecification in pattern coefficients while SRMR-W was more sensitive to misspecification in factor covariance. Moreover, TLI outperformed both CFI and RMSEA in terms of the hit rates of detecting the within-group misspecification in factor covariance. On the other hand, SRMR-B was the only fit index sensitive to misspecification in the between-group model and more sensitive to misspecification in factor covariance than misspecification in pattern coefficients. Finally, we found that the influence of ICC on the performance of targeted fit indices was trivial. 相似文献
89.
Ming Huang Xinye Yang Jichun Xiong Jiarong Li Sen Yang 《Philosophical Magazine Letters》2013,93(9):392-399
ABSTRACTThe interaction between interfacial dislocations and γ/γ′ interface is critical to the high temperature creep properties of single crystal superalloys. However, only a few studies have paid attention to the detailed structure such as local interfacial morphologies and the elemental distribution around interfacial dislocations. In this paper, the interfacial protrusions and related dislocations in a single crystal superalloy after creep at high temperature – low stress have been investigated in detail. It is found that the morphology and size of the interfacial protrusions remain almost the same during the early and middle stages of high temperature creep, which indicates a local equilibrium at the interfacial protrusions. Steps at different height are formed at the γ/γ′ interface at the initial stage of high temperature creep since dislocations could move along the γ/γ′ interface, which indicates that dislocation motion at different creep stage may affect the morphology of γ/γ′ interface. 相似文献
90.
Tsatomu Mashimo Masao Ono Takahiro Kinoshita Xinsheng Huang Toyotaka Osakabe Hiroshi Yasuoka 《Philosophical Magazine Letters》2013,93(11):687-690
It was found that an atomic-scale graded structure was formed, and a phase change occurred, in an In–Pb alloy by the sedimentation of substitutional solute atoms under an ultrastrong gravitational field (820?000?g (maximum); 150°C; 100?h). Continuous gradients in the concentration of Pb (from about 6 to 45?at.%) and In (from about 94 to 55?at.%) and resulting changes in the lattice constant were observed. Fcc (Pb-rich) and tetragonal (In-rich) phases appeared in the strong- and weak-gravity regions respectively from a single starting fct α phase. It is suggested that sedimentation of substitutional atoms can be used to control the compositions and structure of bulk materials and also thin films or layer interfaces. 相似文献