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141.
142.
Adaptive HVAC zone modeling for sustainable buildings   总被引:1,自引:0,他引:1  
Control of energy flows within a building is critical to achieving optimal performance of heating, ventilation and air-conditioning (HVAC) systems. To design optimal HVAC control strategies, a dynamic model of the HVAC system - particularly the building zones that it services - is essential. As analysis of building energy consumption is facilitated by the accurate prediction of indoor environmental conditions, techniques that dynamically model HVAC zones are crucial, and as such, is an active area of research. This paper focuses on real-time HVAC zone model fitting and prediction techniques based on physical principles, as well as the use of genetic algorithms for optimization. The proposed approach is validated by comparing real-time HVAC zone model fitting and prediction against the corresponding experimental measurements. In addition, comparison with prediction results using an algorithm based on feedback-delayed Kalman filters has demonstrated the superiority of the proposed approach in terms of prediction accuracy.  相似文献   
143.
To test the hypothesis that industrial metal contaminants select for microorganisms tolerant to unrelated agents, such as antibiotics, we analyzed metal and antibiotic tolerance patterns in microbial communities in the intake and discharge of ash settling basins (ASBs) of three coal-fired power plants. High-throughput flow-cytometric analyses using cell viability probes were employed to determine tolerances of entire bacterioplankton communities, avoiding bias toward culturable versus nonculturable bacteria. We found that bacterioplankton collected in ASB discharges were significantly more tolerant to metal and antibiotic exposures than bacterioplankton collected in ASB intakes. Optical properties of microorganisms collected in ASB discharges indicated no defensive physiological adaptations such as formation of resting stages or excessive production of exopolymers. Thus, it is likely that the elevated frequency of metal and antibiotic tolerances in bacterioplankton in ASB discharges were caused by shifts in microbial community composition, resulting from the selective pressure imposed by elevated metal concentrations or organic toxicants present in ASBs.  相似文献   
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Only a few studies have examined hormones in psychopathy, and results have been mixed. It has been suggested that because hormone systems are highly interconnected, it may be important to examine multiple systems simultaneously to gain a clearer picture of how hormones work together to predispose for a certain construct. In the present study, we attempt to clarify the role of the hormones cortisol and testosterone in psychopathy by examining both hormones in a community sample of 178 adults demonstrating a wide range of psychopathy scores. Results showed that psychopathy scores were associated with an increased ratio of testosterone (baseline) to cortisol responsivity to a stressor. Psychopathy was not associated with either of these measures independently or with baseline cortisol levels. These findings suggest that these highly interconnected hormone systems may work in concert to predispose to psychopathy. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
146.
The ability to image objects, whether natural or man made, beneath soil is extremely beneficial. The detection scenario becomes increasingly difficult when the object and the soil are composed of the same material, as in the detection of subsurface rocks. The feasibility of detecting rock in similar composition is explored. An active multi-spectral millimeter wave (mmW) imaging system operating from 90–140 GHz is used to detect lava rock buried beneath lava sand at various depths, up to a limit of 64 mm. The principal component analysis method was used in the data processing.  相似文献   
147.
Wheat gluten was reacted with citric acid to produce natural superabsorbent materials able to absorb up to 78 times its weight in water. The properties of the modified gluten samples were characterized using Fourier Transform Infra‐red (FTIR) spectroscopy, thermogravimetric analysis, and water uptake. The reaction between gluten and citric acid was examined for gluten : citric acid ratios of 0.38 : 1 to 0.75 : 1 at temperatures from 100 to 130°C. More citric acid reacted for samples containing higher citric acid concentrations and at higher temperatures. FTIR analyses indicated the presence of carboxylate groups on the modified gluten samples, which resulted in modified samples having higher water uptake values than neat gluten. The sample with a gluten:citric acid ratio of 0.5 : 1 and reaction temperature of 120°C had the largest water uptake value. Also, all modified gluten samples had lower thermal stability than neat gluten. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
148.
Although several good instruments have been developed to measure homonegativity, a comparative psychometric analysis of such instruments has not been published since Schwanberg (1993). The current investigation draws on several samples (including an annual survey of introductory human sexuality students) to examine the psychometric properties of 3 commonly used measures of homonegativity: Hudson and Ricketts' (1980) Index of Homophobia, Herek's (1984, 1988) Attitudes Toward Lesbians and Gay Men, and Morrison and Morrison's (2002) Modern Homonegativity Scale. The validity of each instrument was assessed, and each demonstrated approximately normally distributed data, high reliability, and a unidimensional factor structure. The 3 instruments are strongly intercorrelated and demonstrate a high degree of both convergent and discriminant validity. It is suggested that the Modern Homonegativity Scale has a slight advantage because it results in somewhat more normally distributed data than the other 2 scales. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
149.
Wheat gluten films of various thicknesses formed at 30–70°C were treated with cold sulfuric acid to produce sulfated gluten films. Chemical, thermal, thermal stability, and water uptake properties were characterized for neat and sulfated films. The sulfated gluten films were able to absorb up to 30 times their weight in deionized water. However, this value dropped to 3.5 when the film was soaked in a 0.9% (w/w) NaCl solution. The films were also soaked 4 times in deionized water, and each soaking resulted in a reduced water uptake capacity. The temperature of film formation had no effect on the final water uptake properties. Also, thinner films had higher concentrations of sulfate groups than thicker films; this resulted in higher water uptake values. In addition, sulfated gluten films had comparable glass‐transition temperatures but lower thermal stabilities than the neat gluten films. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
150.
This study investigated how female elementary education pre-service teachers in the United States, Turkey and Taiwan learned spatial skills from structured activities involving discrete, as opposed to continuous, transformations in interactive computer programs, and how these activities transferred to non-related standardized tests of spatial visualization and mental rotation. The study used a pretest, intervention, posttest research design with experimental and comparison groups. The experimental group participated in transformational geometry visualization exercises, once a week for six weeks, for approximately 20 minutes each session. Instruments were standardized measures of spatial visualization and mental rotation; intervention activity worksheets directed the participants through 2D and 3D transformational geometry tasks in computer environments. For Turkish and Taiwanese participants, the experimental group improved significantly more than the control group in spatial visualization, while the American participants showed no such significant improvement.  相似文献   
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