777 research outputs found

    Inelastic Deformation of Metal Matrix Composites

    Get PDF
    The deformation mechanisms of a Ti 15-3/SCS6 (SiC fiber) metal matrix composite (MMC) were investigated using a combination of mechanical measurements and microstructural analysis. The objectives were to evaluate the contributions of plasticity and damage to the overall inelastic response, and to confirm the mechanisms by rigorous microstructural evaluations. The results of room temperature experiments performed on 0 degree and 90 degree systems primarily are reported in this report. Results of experiments performed on other laminate systems and at high temperatures will be provided in a forthcoming report. Inelastic deformation of the 0 degree MMC (fibers parallel to load direction) was dominated by the plasticity of the matrix. In contrast, inelastic deformations of the 90 degree composite (fibers perpendicular to loading direction) occurred by both damage and plasticity. The predictions of a continuum elastic plastic model were compared with experimental data. The model was adequate for predicting the 0 degree response; however, it was inadequate for predicting the 90 degree response largely because it neglected damage. The importance of validating constitutive models using a combination of mechanical measurements and microstructural analysis is pointed out. The deformation mechanisms, and the likely sequence of events associated with the inelastic deformation of MMCs, are indicated in this paper

    Inelastic deformation of metal matrix composites: Plasticity and damage mechanisms, part 2

    Get PDF
    The inelastic deformation mechanisms for the SiC (SCS-6)/Ti-15-3 system were studied at 538 C (1000 F) using a combination of mechanical measurements and detailed microstructural examinations. The objectives were to evaluate the contributions of plasticity and damage to the overall MMC response, and to compare the room temperature and elevated temperature deformation behaviors. Four different laminates were studied: (0)8, (90)8,(+ or -45)2s, and (0/90)2s, with the primary emphasis on the unidirectional (0)8, and (90)8 systems. The elevated temperature responses were similar to those at room temperature, involving a two-stage elastic-plastic type of response for the (0)8 system, and a characteristic three-stage deformation response for the (90)8 and (+ or -45)2s systems. The primary effects of elevated temperatures included: (1) reduction in the 'yield' and failure strengths; (2) plasticity through diffused slip rather than concentrated planar slip (which occurred at room temperature); and (3) time-dependent deformation. The inelastic deformation mechanism for the (0)8 MMC was dominated by plasticity at both temperatures. For the (90)8 and (+ or -45)2s MMCs, a combination of damage and plasticity contributed to the deformation at both temperatures

    The Impacts of Deceptive Advertising on Women Consumer

    Get PDF
    Every day, consumers are exposed to hundreds of commercial messages. The ultimate goal of advertising is to robustly attract consumers by giving them product-related information, application of the products, demonstrate the uses of the products, and guide them to purchase the products. It is absolutely necessary to ensure that consumers perceive advertising as something positive and not otherwise. Consumers’ positive attitudes towards advertising can generate profit for companies, and that is only if advertising can promote products that the consumers needs. Advertising should follow ethical guidelines. Some actions that are quite unethical include women exploitation, influencing consumers to buy a product without providing them with adequate knowledge on what is to be bought, and deceptive advertising, involving false claims and other issues which could lead to moral deterioration of the society. This paper is an effort to find out the impacts of these types of deceptive advertisements on women

    Unusual Tunneling Characteristics of Double-quantum-well Heterostructures

    Get PDF
    We report tunneling phenomena in double In0.53_{0.53}Ga0.47_{0.47}As quantum-well structures that are at odds with the conventional parallel-momentum-conserving picture of tunneling between two-dimensional systems. We found that the tunneling current was mostly determined by the correlation between the emitter and the state in one well, and not by that between those in both wells. Clear magnetic-field-dependent features were first observed before the main resonance, corresponding to tunneling channels into the Landau levels of the well near the emitter. These facts provide evidence of the violation of in-plane momentum conservation in two-dimensional systems.Comment: Submitted to ICPS-27 conference proceeding as a contributed pape

    Drastic Reduction of Shot Noise in Semiconductor Superlattices

    Full text link
    We have found experimentally that the shot noise of the tunneling current II through an undoped semiconductor superlattice is reduced with respect to the Poissonian noise value 2eI2eI, and that the noise approaches 1/3 of that value in superlattices whose quantum wells are strongly coupled. On the other hand, when the coupling is weak or when a strong electric field is applied to the superlattice the noise becomes Poissonian. Although our results are qualitatively consistent with existing theories for one-dimensional mulitple barriers, the theories cannot account for the dependence of the noise on superlattice parameters that we have observed.Comment: 4 Pages, 3Figure

    High Commitment Human Resource Management Practices and Employee Outcomes, HR Attribution Theory and a Proposed Model in the Context of Bangladesh

    Get PDF
    Human resource management (HRM) practices have been studied as a composite or bundle approach with different names including different practices. Each bundle includes common HRM practices of staffing, compensation, training and development, performance appraisal, job design and career development issues with varying dimensions. The present study refers these HRM practices as High Commitment HRM (HCHRM) practices. Prior studies identify these HCHRM practices related to employee outcomes of satisfaction, commitment and retention. Consistent with early findings, the present study believes a relation between HCHRM and employee outcomes. Additionally, HR attribution theory is discussed here to explain the causal relationship between HCHRM practices and employee outcomes. Based on the review of HCHRM practices literatures and existing HRM practices of Bangladesh, a research model is proposed and propositions are developed, The model is expected to be tested in future to identify the relationship among HCHRM practices, HR attribution and employee outcomes in the context of Bangladesh. The proposed model can be tested in other countries as well

    Green HRM for Green Services: A Proposed Best Practices Green HRM Model for Green Banking Performance in Bangladesh

    Get PDF
    The study proposes best practices Green HRM model to improve and innovate green banking services of the banking organizations of Bangladesh. The proposed model provides insights into what extent HRM practices can be linked to capitalize green banking services for greening the economy. Therefore, it can increase the environmental awareness and the theoretical and managerial insights for an effective implementation of green banking through green HRM practices. The banking sector in Bangladesh is at a stage of planning ecological adaptation in response to global green efforts. The present study develops a HRM model suggesting that bank management should link HRM practices to use bank employee capabilities for improving and innovating green banking services in their green strategies. Furthermore, the review on extant literature on green banking across the globe provides evidences of financial sector responses to global ecological concern. This study addresses future empirical study on the proposed model to justify green HRM impact on green services in banking industry and other industries within and beyond Bangladesh. Keywords: Green HRM, Green Management, Best Practices Green HRM, Green Banking, Bangladesh

    User and Provider Perspectives on Improving Mental Healthcare for Syrian Refugee Women in Winnipeg, Manitoba, Canada

    Get PDF
    Introduction: Refugees have higher risk of developing mental illness like anxiety, depression and Post-Traumatic Stress Disorder as they flee from violence. Women refugees may have unique mental healthcare needs due to their vulnerability to gender-based violence and abuse during flight from war. The research question of this study was what the health system can do better to address the mental healthcare needs of refugee women in Winnipeg. Methods: Semi-structured interviews were conducted with 9 Syrian refugee women and 6 service providers/decision makers. The interviews were analyzed using qualitative inductive analysis and coded for themes based on recurring issues. Results: Limited understanding of mental health and illness among refugees, stigma, and the need for culturally competent care were noted by the service providers. System navigation, language, unemployment and safety of family members left behind in Syria were the main concerns of the refugee women. While there are many programs available for refugee women in Winnipeg, lack of collaboration and coordination among providers was identified. Conclusions: This study recommends that service providers use resources developed by UNHCR and Canadian physicians in providing culturally competent care, decision makers take leadership roles in implementing better collaboration among agencies, employers be open in hiring refugees and everyone in the society ensures that the refugee women feel welcomed and included
    corecore