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911.
In the reliability-based design optimization (RBDO) model, the mean values of uncertain system variables are usually applied
as design variables, and the cost is optimized subject to prescribed probabilistic constraints as defined by a nonlinear mathematical
programming problem. Therefore, a RBDO solution that reduces the structural weight in uncritical regions does not only provide
an improved design but also a higher level of confidence in the design. In this paper, we present recent developments for
the RBDO model relative to two points of view: reliability and optimization. Next, we develop several distributions for the
hybrid method and the optimum safety factor methods (linear and nonlinear RBDO). Finally, we demonstrate the efficiency of
our safety factor approach extended to nonlinear RBDO with application to a tri-material structure. 相似文献
912.
Ekrem Sava 《Computers & Mathematics with Applications》2007,54(11-12):1380-1386
In this paper we prove a general theorem on |A;δ|k-summability factors of infinite series under suitable conditions by using an almost increasing sequence, where A is a lower triangular matrix with non-negative entries. Also, we deduce a similar result for the weighted mean method. 相似文献
913.
Information technology (IT) in Saudi Arabia: Culture and the acceptance and use of IT 总被引:2,自引:0,他引:2
The unified theory of acceptance and use of technology (UTAUT), a model of the user acceptance of IT, synthesizes elements from several prevailing user acceptance models. It has been credited with explaining a larger proportion of the variance of ‘intention to use’ and ‘usage behavior’ than do preceding models. However, it has not been validated in non-Western cultures. Using a survey sample collected from 722 knowledge workers using desktop computer applications on a voluntary basis in Saudi Arabia, we examined the relative power of a modified version of UTAUT in determining ‘intention to use’ and ‘usage behavior’. We found that the model explained 39.1% of intention to use variance, and 42.1% of usage variance. In addition, drawing on the theory of cultural dimensions, we hypothesized and tested the similarities and differences between the North American and Saudi validations of UTAUT in terms of cultural differences that affected the organizational acceptance of IT in the two societies. 相似文献
914.
Beyond parallel play: Science befriending the art of method acting to advance healing relationships.
Andres-Hyman Raquel C.; Strauss John S.; Davidson Larry 《Canadian Metallurgical Quarterly》2007,44(1):78
Research underscores the central role of factors in healing that appear to relate to the therapeutic relationship. These nonspecific or common factors and placebo effects are often overshadowed by an emphasis in the field on particular empirically supported therapies. Yet relationship variables account for a greater proportion of the variance in treatment outcomes than the technical intervention employed, representing a notable blind spot in our science and, by extension, our practice. As a consequence, clinical instruction in psychology and in the health professions more broadly generally lacks adequate specificity with respect to how to cultivate a healing relationship. Through the elaboration of several techniques derived from theatrical traditions, the authors propose that method acting and similar schools of drama provide a method for honing clinical skills in these areas that is amenable to empirical scrutiny. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
915.
In a birth cohort prenatally exposed to rubella, we assessed whether prospectively documented premorbid neuromotor dysfunction, mannerisms, deviant behaviors, and temperament during childhood and adolescence were impaired in cases who developed depressive disorder (DD) relative to rubella-exposed controls and cases who developed schizophrenia spectrum psychosis (SSP). Premorbid neuromotor dysfunction and mannerisms were not increased among DD cases compared to controls or SSP cases. With regard to temperament, approachability was greater in DD cases than in controls and SSP cases. There were numerical increases in the proportions of DD cases with premorbid deviant behaviors compared to controls, but the findings fell short of statistical significance; the proportion of subjects with deviant behaviors in DD cases was similar to that found for SSP. These results indicate that premorbid neuromotor dysfunction and mannerisms may be specific to SSP among major psychiatric disorders in this cohort, and suggest that premorbid deviant behaviors are increased in both DD and SSP. Greater premorbid approachability may be associated with an increased risk of adult DD. Implications of these findings for school psychology are furnished. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
916.
爆轰法制备纳米颗粒的探索 总被引:1,自引:0,他引:1
综述了爆炸应用的发展和采用爆轰法合成纳米粉体的实践工作,结合控制爆破在工程建设中发挥的作用,提出“控制爆轰技术”应用于纳米颗粒合成,据此总结讨论和探索了爆轰法制备纳米颗粒存在的内因素和外因素。并指出,内因素是采用爆轰法制备纳米粉体的关键因素。 相似文献
917.
Effectiveness of any alternative dispute resolution (ADR) method depends on the national legal system to which it is subjected. In Singapore, the increasing growth in the use of ADR methods may be adduced to developments in the Singapore legal environment. This paper reviews the characteristics of the Singapore national legal system for arbitration. It examines how the legal system facilitates effective use of ADR. By its features, the Singapore national legal system ensures parties’ autonomy but deters parties from taking opportunistic advantage of the voluntary nature of ADR. It enables procedural flexibility, and confidentiality of arbitration proceedings. It insulates the arbitration process from intervention from the Singapore courts and from corruption; and it provides maximum judicial support in the arbitral process. Hence, it ensures that disputes can be brought to a conclusion within a reasonable amount of time, at a reasonable cost, as well as preserving business relationships. The Singapore legal system insures the integrity of arbitration and the independence of arbitrators and arbitral institutions by immunity provisions. In addition, the legal system enhances the use of mediation and conciliation in a sequential tier with arbitration by providing a time limit for mediation or conciliation to terminate should they fail to produce a mutually acceptable settlement. In Singapore, the court system is generally known to be efficient; hence, ADR faces the practical challenge of becoming lengthier than court proceedings. The continuing search for and use of expedited arbitration procedures by arbitral institutions such as the Singapore International Arbitration Centre should reduce this challenge. This paper provides useful information on how a national legal system may be designed to support the use of ADR methods and facilitate their effectiveness. 相似文献
918.
K. Sopian M. Syahri S. Abdullah M. Y. Othman B. Yatim 《Canadian Metallurgical Quarterly》2007,133(1):26-31
Theoretical and experimental investigations on an unglazed solar hot water heater with integrated storage system were conducted. The system was comprised of a collector and storage tank which was integrated into one unit. All parts of the system have been fabricated from fiberglass reinforced polyester (GFRP). The absorber plate has water tubes of semielliptical shape. The width and length of the absorber plate were 1.4 and 1.8?m, respectively. The absorber plate was fabricated from GFPR using a special resin composition that provides good thermal conductivity and absorptivity. The storage tank has a capacity of 496?L. The storage tank is of sandwich construction with a core material made of polyurethane foam that combines stiffness and lightness of the structure with very good thermal insulation properties. An average tank temperature of 53°C was achieved at an average solar radiation level of 700?W/m2 and ambient temperature of 28°C. The thermal efficiencies of the system were evaluated at 48 and 57% for cloudy and clear days, respectively. Transient performance of the system was predicted by solving the mathematical models consisting of energy balance equations of the system that have been converted to finite difference form and solved by a personal computer. The experimental results were in close agreement as has been found with the theoretical predictions. 相似文献
919.
The Singapore government is encouraging construction enterprises to venture abroad for exporting their services and become global players since the local construction pie is shrinking and the global market is growing. The Building and Construction Authority of Singapore has revamped the contractors registration system with the hope of bringing about merger and acquisition of companies for improving the local contractors’ standing in the global construction scene. To diversify into new markets in a new environment, which is very different from local environment, requires diversification vis-à-vis exporting strategy. This study examines the attitudes and views of contractors, operating in Singapore (excluding foreign contractors), on how the strategic move should be focused for diversification vis-à-vis exporting services. The aim of this study is to establish the survival skills necessary for Singapore’s construction small and medium sized enterprises (SMEs) to venture abroad. A postal questionnaire survey was conducted and the results show that local construction SMEs who have diversified have reaped the benefits derived from diversification into new markets abroad. The main conclusions are that construction SMEs have to export their services in order to survive and they can enhance their export capabilities by forming a consortium with the help of local government. 相似文献
920.
Martijn van Praagh Magnus Persson Kenneth M. Persson 《Canadian Metallurgical Quarterly》2007,133(7):750-757
The mobility of pollutants from air pollution control (APC) residues is strongly influenced by its contact with water. This study aims to verify the applicability of time-domain reflectometry (TDR) to infer water and solute movement in situ in an APC residue–compost mixture in a laboratory column. The calibrated dielectric permittivity–volumetric water content relationship (K?θv) for the material shows a distinct plateau at midrange volumetric water contents, which are underestimated by Topp’s K?θv model throughout the studied range. The coating of probes enables a clear TDR signal collection and analysis up to electrical conductivity values of 280?mS?cm?1. Heterogeneities in packing and channel flow in the column are revealed by TDR measurements. Water contents inferred by TDR signal analysis require careful interpretation when used in materials such as APC residues, due to the high amount of water bound in the hydration shells of ions released into the pore water. 相似文献