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1.
This study examines the links between antecedents and consequences of Gabonese teachers' (N= 152) work motivation. The theoretical underpinnings are based on the Motivational Model of Job Burnout (MMJB) which is grounded in Self-Determination Theory (SDT) and states that the more supervisors satisfy an employee's need for self-determination, competence, and relatedness, the more self-determined is the latter's work motivation. The level of self-determined motivation has an impact on job satisfaction, which in turn determines life satisfaction. Higher levels of self-determined motivation also buffer emotional exhaustion and psychological distress. The model was confirmed via structural equation modeling and provides support for the validity and generalizability of the MMJB and SDT. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
An effective two-stage method has been developed for imparting antimicrobial properties to regular polyethylene terephthalate (R-PET), polyethylene glycol modified polyethylene terephthalate (PEG-M-PET), R-PET/Cotton blend (R-PET/C) and PEG-M-PET/Cotton blend (PEG-M-PET/C) fabrics. The method consists of partial hydrolysis of the fabrics to create carboxylic groups in PET macromolecules followed by subsequent reaction with dimethylalkylbenzyl ammonium chloride (DMABAC) under alkaline conditions. The reaction conditions such as pH, reaction temperature and time, carboxylic content, and DMABAC concentration were studied. Characterization of the finished fabrics was carried out through scanning electron microscopy (SEM) and Fourier transform infrared spectra (FTIR). All the modified PET fabrics showed excellent antibacterial activity towards Gram-positive (Bacillus mycoides), Gram-negative (Escherichia coli), and nonfilamentous fungus (Candida albicans). The achieved antimicrobial functions on the PET fabrics are durable in repeated laundering processes. Even after laundering 10 times the fabrics could still provide more than 85% of its antimicrobial activity against B. mycoides, E. coli, and C. albicans. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
3.
穷举法是程序设计中经常用到的一种算法,用来解决一些用常规的数学方法无法解决的问题.文章通过两个典型的例子对穷举法的思路和有关注意事项进行了分析,供编程学习者参考.  相似文献   
4.
李圣华 《炭素技术》2006,25(2):49-55
针对炭素制品生产过程产生的粉尘、沥青烟气、噪声等主要涉及工业卫生及环境保护等方面的问题进行剖析,并对治理方法做了简要的介绍。  相似文献   
5.
双活性基活性染料真丝绸染色工艺研究   总被引:7,自引:0,他引:7  
双活性基活性染料用于真丝绸染色有诸多影响因素:缚酸剂用碳酸氢钠比碳酸钠的固色率高用量在2%~4%,pH为8~9时最为合适:染色温度从60℃升到85℃时固色率提高3%~8%,超过85℃时易造成“灰伤”.当元明粉的用量从30g/l升到60g/l时上染率和固色率提高10%。随着浴比的增加,其固色率会有不同程度的降低,在实验条件下,浴比为1:40最好。通过上染曲线,讨论了染色过程的控制。  相似文献   
6.
Organizations today face shortages of IT personnel. We investigated workplace factors in one state government in hope of identifying factors that influence perceived organizational support (POS) within an IT work environment. A combination of job characteristics (challenging job and perceived workload), job stressors (work exhaustion, role conflict, and role ambiguity), and the organization’s discretionary actions (pay-for-performance and mentoring opportunities) were measured and hierarchical regression was used to determine the relationships. Four control variables were also included (age, gender, organizational tenure, and professional versus administrator status). Role ambiguity, role conflict, work exhaustion, career mentoring, and pay-for-performance together explained 62% of the variance in the IT employees’ POS. Career mentoring and role ambiguity explained most of the variance.  相似文献   
7.
The amendment of patent law of India in 2005 to fulfill her international obligation under the TRIPS Agreement (World Trade Organization Agreement on Trade Related Intellectual Property Rights) was an outcome of an attempt to balance the competing interests of several stakeholders, including indigenous pharmaceutical companies, multi-national pharmaceutical companies, non-governmental organizations and civil society groups concerned with access to affordable drugs. The adverse consequence of this delicate balancing is introduction of some provisions in the Act whose compatibility with the TRIPS Agreement is questionable, and which therefore are prone to litigations. Section 107A(b) of the amended patent law dealing with parallel imports is one such provision, which, if interpreted word for word could have significant connotations for the rights of a patent owner. This article aims to examine the inconsistencies intrinsic in Section 107A(b) and discusses the divergences in the Indian patent law associated with the doctrine of exhaustion and parallel imports. This article also proposes legal amendments with a view to eliminate inconsistencies intrinsic in the section and enlarge the ambit of the exhaustion principle conceptualized therein, while concurrently remaining compliant with the TRIPS Agreement.  相似文献   
8.
Probabilistic model checking for the quantification of DoS security threats   总被引:1,自引:0,他引:1  
Secure authentication features of communication and electronic commerce protocols involve computationally expensive and memory intensive cryptographic operations that have the potential to be turned into denial-of-service (DoS) exploits. Recent proposals attempt to improve DoS resistance by implementing a trade-off between the resources required for the potential victim(s) with the resources used by a prospective attacker. Such improvements have been proposed for the Internet Key Exchange (IKE), the Just Fast Keying (JFK) key agreement protocol and the Secure Sockets Layer (SSL/TLS) protocol. In present article, we introduce probabilistic model checking as an efficient tool-assisted approach for systematically quantifying DoS security threats. We model a security protocol with a fixed network topology using probabilistic specifications for the protocol participants. We attach into the protocol model, a probabilistic attacker model which performs DoS related actions with assigned cost values. The costs for the protocol participants and the attacker reflect the level of some resource expenditure (memory, processing capacity or communication bandwidth) for the associated actions. From the developed model we obtain a Discrete Time Markov Chain (DTMC) via property preserving discrete-time semantics. The DTMC model is verified using the PRISM model checker that produces probabilistic estimates for the analyzed DoS threat. In this way, it is possible to evaluate the level of resource expenditure for the attacker, beyond which the likelihood of widespread attack is reduced and subsequently to compare alternative design considerations for optimal resistance to the analyzed DoS threat. Our approach is validated through the analysis of the Host Identity Protocol (HIP). The HIP base-exchange is seen as a cryptographic key-exchange protocol with special features related to DoS protection. We analyze a serious DoS threat, for which we provide probabilistic estimates, as well as results for the associated attacker and participants' costs.  相似文献   
9.
In this study, stress relaxation compression tests were performed to investigate the strain rate sensitivity, activation volume and mobile dislocations in carbon nanotubes/aluminum (CNTs/Al) composites. The results reveal that, with the addition of CNTs, the strain rate sensitivity of CNTs/Al increased. Meanwhile, a smaller V* of CNTs/Al compared with pure Al was attributed mainly to the CNT-Al interfaces and partly to the increased forest dislocations cutting activities in grain interior, which was related to the tendency of short ranges order formation during plastic deformation. The incorporation of CNTs also improved the dislocation storage capability and reduced the dislocation velocity, leading to a lower mobile dislocation exhaustion rate.  相似文献   
10.
建筑工人职业流动率较高,建筑工人频繁的职业流动不利于建筑产品供给效率的提高。本文基于资源保存理论和情感事件理论,构建了建设项目组织情境下辱虐管理影响建筑工人流动意愿的被调节的中介效应模型。研究结果发现,辱虐管理显著正向影响建筑工人的流动意愿,情绪耗竭部分中介辱虐管理和建筑工人流动意愿之间的关系,建筑工人传统性反向调节辱虐管理和建筑工人流动意愿之间的关系以及情绪耗竭的中介效应。建筑工人传统性越高,辱虐管理和建筑工人流动意愿之间的正向联系就越弱,情绪耗竭的中介效应也越弱。  相似文献   
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