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121.
122.
Umberto C. Gatti Susan M. Bogus Suzanne Schneider 《Construction Management & Economics》2014,32(6):548-564
The monitoring of construction workforce physical strain can be a valuable management strategy in improving workforce productivity, safety, health, and quality of work. Nevertheless, clear relationships between workforce performance and physical strain have yet to be established. An exploratory investigation of the relationship between task level productivity and physical strain was conducted. Nine participants individually performed a four-hour simulated construction task while a wearable physiological status monitor continuously assessed their physiological condition. Heart rate, relative heart rate, and breathing rate were utilized as predictors of physical strain, and task level–single factor productivity was used as an index of productivity. Numerous regression models were generated using the collected data. This investigation initially unsuccessfully attempted to establish a relationship between physiological condition and productivity at the individual worker level. However, an analysis of the regression models showed that there is a relationship between productivity and either heart rate or relative heart rate at the group level, and that this relationship is parabolic. Breathing rate was proved to not be a significant predictor of productivity. Research results significantly improve understanding of the relationship between work physiology and task productivity. Researchers and practitioners may use the tested monitoring devices, analysis methods, and results to design further applied studies and to improve workforce productivity. 相似文献
123.
Jooyoung Jang Susan Bell Trickett Christian D. Schunn J. Gregory Trafton 《International journal of human-computer studies》2012,70(11):812-827
Spatial arrangement of information can have large effects on problem solving. Although such effects have been observed in various domains (e.g., instruction and interface designs), little is known about the cognitive processing mechanisms underlying these effects, nor its applicability to complex visual problem solving. In three experiments, we showed that the impact of spatial arrangement of information on problem solving time can be surprisingly large for complex real world tasks. It was also found that the effect can be caused by large increases in slow, external information searches (Experiment 1), that the spatial arrangement itself is the critical factor and the effect is domain-general (Experiment 2a), and that the underlying mechanism can involve micro-strategy selection for information encoding in a response to differing information access cost (Experiment 2b). Overall, these studies show a large slowdown effect (i.e., approximately 30%) that stacking information produces over spatially distributed information, and multiple paths by which this effect can be produced. 相似文献
124.
Pervasive systems must offer an open, extensible, and evolving portfolio of services which integrate sensor data from a diverse range of sources. The core challenge is to provide appropriate and consistent adaptive behaviours for these services in the face of huge volumes of sensor data exhibiting varying degrees of precision, accuracy and dynamism. Situation identification is an enabling technology that resolves noisy sensor data and abstracts it into higher-level concepts that are interesting to applications. We provide a comprehensive analysis of the nature and characteristics of situations, discuss the complexities of situation identification, and review the techniques that are most popularly used in modelling and inferring situations from sensor data. We compare and contrast these techniques, and conclude by identifying some of the open research opportunities in the area. 相似文献
125.
126.
Timothy Rumbell John Barnden Susan Denham Thomas Wennekers 《Autonomous Agents and Multi-Agent Systems》2012,25(1):1-45
Emotion mechanisms are often used in artificial agents as a method of improving action selection. Comparisons between agents
are difficult due to a lack of unity between the theories of emotion, tasks of agents and types of action selection utilised.
A set of architectural qualities is proposed as a basis for making comparisons between agents. An analysis of existing agent
architectures that include an emotion mechanism can help to triangulate design possibilities within the space outlined by
these qualities. With this in mind, twelve autonomous agents incorporating an emotion mechanism into action selection are
selected for analysis. Each agent is dissected using these architectural qualities (the agent architecture, the action selection
mechanism, the emotion mechanism and emotion state representation, along with the emotion model it is based on). This helps
to place the agents within an architectural space, highlights contrasting methods of implementing similar theoretical components,
and suggests which architectural aspects are important to performance of tasks. An initial framework is introduced, consisting
of a series of recommendations for designing emotion mechanisms within artificial agents, based on correlations between emotion
roles performed and the aspects of emotion mechanisms used to perform those roles. The conclusion discusses how problems with
this type of research can be resolved and to what extent development of a framework can aid future research. 相似文献
127.
Aaron J. Welsh Denis Dezest Liviu Nicu Susan Trolier‐McKinstry 《Journal of the American Ceramic Society》2017,100(3):848-858
The functional properties of electroceramic thin films can be degraded by subtractive patterning techniques used for microelectromechanical (MEMS) applications. This work explores an alternative deposition technique, where lead zirconate titanate (PZT) liquid precursors are printed onto substrates in a desired geometry from stamp wells (rather than stamp protrusions). Printing from wells significantly increased sidewall angles (from ~1 to >35 degrees) relative to printing solutions from stamp protrusions. Arrays of PZT features were printed, characterized, and compared to continuous PZT thin films of similar thickness. Three‐hundred‐nanometer‐thick printed PZT features exhibit a permittivity of 730 and a loss tangent of 0.022. The features showed remanent polarizations of 26 μC/cm2, and coercive fields of 95 kV/cm. The piezoelectric response of the features produced an e31,f of ?5.2 C/m2. This technique was also used to print directly atop prepatterned substrates. Optimization of printing parameters yielded patterned films with 90° sidewalls. Lateral feature sizes ranged from hundreds of micrometers down to one micrometer. In addition, several device designs were prepatterned onto silicon on insulator (SOI) wafers (Si/SiO2/Si with thicknesses of 0.35/1/500 μm). The top patterned silicon was released from the underlying material, and PZT was directly printed and crystallized on the free‐standing structures. 相似文献
128.
Javad Tavakoli Mary Susan Brewer Aniseh Zarei Jelyani Parviz Estakhr 《International Journal of Food Properties》2017,20(12):3256-3265
The oxidative stability of refined olive oil with incorporated Pistacia khinjuk fruit oil (PKFO; 0.5%, 1%, 2%, 5%, and 10%) during thermal processing at 170ºC for 8 h was evaluated. The conjugated diene values, carbonyl values, acid values, oil/oxidative stability indices, and total tocopherol content were measured during thermal processing. Olive oil containing 0.5% PKFO was identified as the most oxidative stable oil followed by oils containing 100 ppm TBHQ and 1, 5, 10, and 2% PKFO. No significant difference between samples of olive oil containing 100 ppm TBHQ and 1% PKFO was observed. Thus, it was concluded that PKFO at levels lower than 1% could provide stronger antioxidation activity in comparison with TBHQ (the strongest syntactic antioxidant used in the food industry). Moreover, reduction in tocopherol compounds during thermal processing was higher in olive oil containing TBHQ as compared to those in pure olive oil. 相似文献
129.
Niccols Alison; Milligan Karen; Sword Wendy; Thabane Lehana; Henderson Joanna; Smith Ainsley; Liu Jennifer; Jack Susan 《Canadian Metallurgical Quarterly》2010,24(3):466
To examine the impact of integrated treatment programs (those with substance use treatment and pregnancy-, parenting-, or child-related services) on maternal mental health, we compiled a database of studies of integrated programs published between 1990 and 2007 with outcome data on maternal mental health. There were 18 cohort studies, 3 randomized trials, and 2 quasi-experimental studies. Of the five studies comparing integrated to nonintegrated programs, three studies provided enough information to allow for them to be combined in a meta-analysis. The average effect size was 0.23 (95% CI = 0.15 to 0.31, SE = 0.04), p Q = 5.66, p = .059. This meta-analysis is the first systematic quantitative review of studies evaluating the impact of integrated programs on maternal mental health. Findings suggest that integrated programs may be associated with a small advantage over nonintegrated programs in improving maternal mental health. This review highlights the need for further research with improved methodology, study quality, and reporting to improve our understanding of how best to meet the mental health needs of mothers with substance abuse issues. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
130.
South Susan C.; Krueger Robert F.; Iacono William G. 《Canadian Metallurgical Quarterly》2009,21(4):622
The Dyadic Adjustment Scale (DAS; G. B. Spanier, 1976) is the most widely used inventory of relationship satisfaction in the social sciences, yet the question of whether it is measuring the same concept in men and women has never been addressed. In the current study, the authors examined the factor structure of the DAS in a sample of 900 currently married couples who participated in the Minnesota Twin Family Study. Confirmatory factor analysis was applied to a second-order factor solution with Spanier’s four factors (Dyadic Consensus, Dyadic Satisfaction, Dyadic Cohesion, Affectional Expression) loading on one higher order factor (Relationship Adjustment), to test for measurement invariance across gender. The second-order solution was relatively invariant across gender, even when taking into account the nonindependent nature of the data. This suggests that the best conceptualization of the DAS is one of a gender-invariant measure of marital adjustment with four distinct subfactors and that differences between men and women on any of these constructs can be interpreted by both clinicians and researchers as true mean differences rather than measurement bias. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献