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111.
Personal exposure in a displacement ventilated room is examined. The stratified flow and the considerable concentration gradients necessitate an improvement of the widely used fully mixing compartmental approach. The exposure of a seated and a standing person in proportion to the stratification height is examined by means of full-scale measurements. A breathing thermal manikin is used to simulate a person. It is found that the flow in the boundary layer around a person is able to a great extent to entrain and transport air from below the breathing zone. In the case of non-passive, heated contaminant sources, this entrainment improves the indoor air quality. Measurements of exposure due to a passive contaminant source show a significant dependence on the flow field as well as on the contaminant source location. Poor system performance is found in the case of a passive contaminant released in the lower part of the room close to the occupant. A personal exposure model for displacement ventilated rooms is proposed. The model takes the influence of gradients and the human thermal boundary layer into account. Two new quantities describing the interaction between a person and the ventilation are defined. 相似文献
112.
Peter Gregory 《Advanced materials (Deerfield Beach, Fla.)》1996,8(6):463-466
An influential and refreshingly frank report on the state of health of non-university materials research in Germany has recently been published. National Research Centers, Max Planck Institutes, and Fraunhofer Institutes are among the organizations covered. Recommendations are made on the basis of materials type, and on the performances of the individual institutes. The conclusions of this self-portrait, painted by representatives of the organizations themselves along with participants from the universities, industry, and state, will provide food for thought for both German materials scientists and those in other European countries concerned with the future development of this crucial economic sector. 相似文献
113.
When West meets East: Contributions of Eastern traditions to the future of psychotherapy. 总被引:1,自引:0,他引:1
Bankart C. Peter; Koshikawa Fusako; Nedate Kaneo; Haruki Yutaka 《Canadian Metallurgical Quarterly》1992,29(1):141
Discusses 2 interrelated traditions as they are reflected in contemporary and traditional approaches to psychotherapy in Japan. One uses various meditational and self-focusing instructional sets whose common goal is to facilitate the slowing down, deepening, and clearer focusing of sensory and interpersonal awareness. The 2nd tradition focuses on physical self-regulation and autonomic self-control through exercises that foster enhanced voluntary control over physical states and processes. Eastern psychology offers a set of practices that help the individual overcome the inherent selfishness of his/her isolated experience. The goals of such work include recognition of gratitude to important people in the client's life, rediscovery of the joy of meaningful work, and the experience of a unifying cosmic consciousness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
114.
115.
This study examined people's willingness to restrain themselves during a naturally occurring social dilemma situation—the 1991 California water shortage. The findings suggest that people are more willing to support authorities who make water conservation decisions when these authorities use fair decision-making procedures. Procedural justice effects were not found to be influenced by the perceived severity of the resource scarcity or the favorability of the authorities' decisions. Rather, they were primarily based on concerns for having positive, relational bonds to the authorities. These relational effects were found to be stronger for those respondents who identify more with their community. The study suggests that the effectiveness of authorities is primarily linked to the nature of their social bonds with community members. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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117.
The aim of this study was to contrast the validity of two opposing explanatory hypotheses about the effect of online communication on adolescents' well-being. The displacement hypothesis predicts that online communication reduces adolescents' well-being because it displaces time spent with existing friends, thereby reducing the quality of these friendships. In contrast, the stimulation hypothesis states that online communication stimulates well-being via its positive effect on time spent with existing friends and the quality of these friendships. We conducted an online survey among 1,210 Dutch teenagers between 10 and 17 years of age. Using mediation analyses, we found support for the stimulation hypothesis but not for the displacement hypothesis. We also found a moderating effect of type of online communication on adolescents' well-being: Instant messaging, which was mostly used to communicate with existing friends, positively predicted well-being via the mediating variables (a) time spent with existing friends and (b) the quality of these friendships. Chat in a public chatroom, which was relatively often used to talk with strangers, had no effect on adolescents' well-being via the mediating variables. 相似文献
118.
Confluent graphs capture the connection properties of train tracks, offering a very natural generalization of planar graphs,
and—as the example of railroad maps shows—are an important tool in graph visualization. In this paper we continue the study
of confluent graphs, introducing strongly confluent graphs and tree-confluent graphs. We show that strongly confluent graphs
can be recognized in NP (the complexity of recognizing confluent graphs remains open). We also give a natural elimination
ordering characterization of tree-confluent graphs, and we show that this class coincides with the (6,2)-chordal bipartite
graphs. Finally, we define outerconfluent graphs and identify the bipartite permutation graphs as a natural subclass. 相似文献
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120.
研制成用LD泵浦的声光调Q的Nd:YVO4-KTP腔内倍频激光器,得到了TEM00模、频率高达100kHz的稳定的532um绿激光脉冲系列输出,阈值泵浦功率为27mW;在连续570mW的泵浦功率下,绿激光脉冲的峰值功率达1100W,脉宽为4.6us;输出功率稳定,在±5℃的工作温度变化下,输出功率变化小于±2%。此种器件可望得到广泛的应用。 相似文献