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51.
Rainwater collection as a possible water source in developing countries is introduced. The major parameters in calculating the size of the tank are defined. Six methods that have been used previously to relate demand, storage, reliability and the rainfall pattern are compared to the Ottawa Model over a wide range of demands. 相似文献
52.
An introduction to parallel process interventions is provided by a comprehensive review of the theoretical constructs and empirical studies regarding the use of the parallel process in supervision. Although more direct investigations of the parallel process are needed, we conclude that parallel process interventions within the supervisory relationship can be extremely potent and impactful. Recommendations for the facilitative application of the parallel process in the supervision and training of professional psychologists, as well as case examples, are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Preliminary Development of a Model and Measure of Computer-Mediated Communication (CMC) Competence 总被引:1,自引:0,他引:1
Brian H. Spitzberg 《Journal of Computer-Mediated Communication》2006,11(2):629-666
The rationale for developing a theoretical model of computer-mediated communication (CMC) competence is established through review of social trends in the use of new media technologies. Special attention is paid to the role new media play in the formation and development of personal relationships. A model of CMC competence is then developed along the lines of motivation, knowledge, skills, context, and outcomes as a metaphorical typology for organizing existing CMC research. This research is reviewed as it informs, and is organized by, the model of CMC competence. A sampling of formal propositions resulting from the model is elaborated, and the results of preliminary pilot studies of the model are reviewed. The model is offered as a first step in examining individual differences in the domain of CMC relationships and media choice. 相似文献
54.
A specific radioimmunoassay for platelet-activating factor (PAF) sensitive in the range 10–1000 pg (0.02–2 pmoles) has been
developed. Detailed quantitative hapten inhibition studies showed specificity for the acetyl group at C-2 of PAF, a requirement
for the ether linkage at C-1 and some tolerance for substituents on the choline nitrogen. No significant cross-reactivity
was found with phosphatidylcholine and lysophosphatidylcholine or with lysoPAF.
Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl
Ether Lipids, Tokyo, Japan, May 1989. 相似文献
55.
56.
M.C. Wu Y.K. Chen T. Tanbun-Ek R.A. Logan M.A. Chin 《Photonics Technology Letters, IEEE》1991,3(10):874-876
The tunabilities of both the wavelength and the pulse-width of monolithic mode-locked semiconductor lasers are demonstrated. Pulses shorter than 1.6 ps, tunable over 8.8 mu m, have been generated by a temperature-tuned monolithic colliding pulse mode-locked (CPM) quantum-well laser. For a fixed wavelength, the pulse-width is independently controlled from 1.2 ps to longer than 3 ps by external bandpass filters. Near transform-limited time-bandwidth products of 0.34 were maintained throughout the tuning processes.<> 相似文献
57.
Katherine A. B. Logan Michael J. S. Floate 《Journal of the science of food and agriculture》1985,36(11):1084-1092
For 30 acid upland and hill soils, with initial pH from 3.5 to 5.8, and loss on ignition from 14% to 94%, cation exchange capacity varied with pH according to the relationship CEC = m pH+C, where m and C are characteristic of each soil. The slope m depended on loss on ignition (LOI), and is given by: m=Δ CEC/Δ=0.22 LOI+1.92. Because of these relationships, CEC measured at the natural pH of the soil (in 0.025 M MgSO4 solution) is more relevant to field conditions than a conventional measurement at pH7. An improved method for estimating lime requirement (LR) of these soils was developed, based on the relationship found between LR and the difference in CEC (ΔCEC) between that at the natural pH of the soil and that at the target pH of 5.5: LR=1.12 ΔCEC+1.48. Lime requirement can therefore also be estimated from loss on ignition using the earlier relationships, and is given by: LR=(0.25 LOI+2.15) Δ+1.48, where Δ is the difference between the natural pH (in 0.025 M MgSO4) and the target pH. Predictions based on this agreed well with results for a further 10 soils. 相似文献
58.
Because families seek help from pediatricians for a variety of child behavioral and psychological problems, interdisciplinary collaboration between pediatrics and psychology has much potential. Such a collaboration would offer new opportunities for psychologists in primary health care settings and could help fulfill the significant psychosocial training needs of pediatricians delivering primary, secondary, and tertiary services. These needs are particularly acute for secondary care, with its increasing emphasis on child development, psychosocial aspects of pediatrics, developmental disabilities, adolescence, and school problems. Additionally, collaboration could enhance treatment of a wide variety of problems with both medical and psychological components such as hyperactivity, enuresis, juvenile onset obesity, and childrearing problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
60.
We study non-linear behaviour in a model chemical reaction scheme (proposed by Sal?nikov), in which a single chemical species undergoes a two-stage, first-order decay process. The second stage is exothermic and has a temperature-dependent rate, and as a result, spontaneous oscillations in the temperature and the concentration of an intermediate chemical are known to be possible. An additional oscillation is imposed on the system by varying the ambient temperature in a sinusoidal manner. Primary resonance occurs when the forcing frequency coincides with the frequency of the natural oscillations in this scheme and an infinite sequence of super-and subharmonic resonances is also present. Chaos is possible for appropriate parameter values and may result either from the Feigenbaum period-doubling cascade, or else as a result of the Ruelle-Takens approach through quasi-periodicity. 相似文献