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The capability to predict and evaluate the motor pressure during each phase by means of a numerical analysis can significantly increase the efficiency of the preliminary design process with a reduction of both the motor development and operational costs. This paper aims to perform numerical simulation to analyze the ignition transient in solid rocket motor by solving Euler equation coupled with some semi-empirical correlations. These relations take into account the main phenomena affecting the ignition transient. Coupling relationships include the heat transfer of the gas to the propellant and erosive burning rate relationship.

The current research effort divides motor into series of control volumes along the port axis, and the variation of port area, burning surface and burning rate along the port are taken into account. A set of governing equations are then solved using explicit, time-dependent, predictor-corrector finite difference method. The numerical model helps to capture and embed shock wave associated with igniter flow within the solution. Second-order artificial viscosity dampens out the numerical oscillations due to sharp gradient within the flow field. The developed computer code predicts the start-up characteristics of motor. The study also provides comparison of simulation results with in-house experimental motor.

Simulations are performed with and without erosive burning to demonstrate that the flow model is a good physical approximation of motor. Numerical results calculated by this model without erosive burning are not in good agreement with experimental results. This minor discrepancy has motivated the inclusion of erosive burning in numerical model. The simulated results are then compared with the experimental data for head-end and rear-end pressure. The agreement between simulation and experiment is remarkable. In summary, major finding of this study is that unsteady quasi-one-dimensional gas dynamic model can capture the flow field in the motor during ignition transient effectively.

Unsteady quasi-one-dimensional gas dynamic model can capture the flow field in the motor during ignition transient effectively. However, in systems where two- and three-dimensional effects are pre-dominant, one would require to develop a more elaborate, multi-dimensional model which will allow for further understanding of the flow behavior and eventually lead to modeling of rocket motors with more complex geometries.

The close agreement between experimental and simulation results can be considered as forced to some degree, because the general mathematical model of erosive burning contains a free variable erosive burning exponent. However, in future, this variable can be established a priori by erosive burning tests.

The solid propellant ignition process consists of series of rapid events and must be completed in a fraction of a second. An understanding of the dynamics of ignition has become increasingly vital with the development of larger and more sophisticated solid propellant rocket motors. This research effort provides the simulation framework to predict and evaluate the motor pressure during each phase by means of a numerical analysis, thus significantly increasing the efficiency of the preliminary design process with a reduction of both the motor development and operational costs.

This study aims to test the relationship between virtual knowledge sharing (VKS) and team effectiveness (TE) during the COVID-19 pandemic. The study also explores the moderating role of collaborative technologies.

This is a cross-sectional study conducted in the service sector of India. A purposive sample of 321 knowledge workers from National Capital Region of India was used. Questionnaires were distributed to knowledge workers working in a virtual environment. The hypotheses were tested with confirmatory factor analysis and structural equation modeling (SEM) using partial least square-SEM.

The study reveals that, amid the COVID-19 pandemic, virtual knowledge sharing (VKS) positively affects team effectiveness (TE). Furthermore, the impact of VKS on TE is contingent upon the utilization of collaborative technologies.

The study contributes to the existing literature by exploring the impact of VKS on TE during the COVID-19 pandemic and the importance of collaborative technologies in facilitating virtual team collaboration, which has practical implications for organizations seeking to enhance TE in virtual environments.

OF all the delightful recreations classed, for divers professional reasons, under the general designation of work, which cause the librarian's existence to be regarded with envious eyes as one of the most joyous and irresponsible on earth, the most delectable is surely that of cataloguing ; and the moments when the cataloguer feels himself fullest of enthusiasm, when he knows it would be impossible to exchange his lot with any human being, are those spent in the absorbing occupation of correcting proofs, for then to the more sensuous delights of the game are added the zest and ardour of combat. Some day I may, with the editor's sanction, make a few observations on the pleasures of cataloguing in general: for the present I am going to consider only this final phase. A curious feature of the pastime or “work,” to adopt the conventional phraseology, is that some people are unable to see the fun of it and innocently suppose the term “work” to be meant seriously. Still, when one reflects that every sport is looked upon by outsiders either as a deadly form of depravity, or as idiotically tedious and laborious, it is clear that this feature is neither wonderful nor exceptional. Golf, angling, football, punting, mountaineering, even book‐collecting, are each looked upon as “work” by those who love other kinds of recreation, which may yet be in reality not a whit less arduous.

The purpose of this paper is to identify higher authority organizational stressors encountered by higher education deans.

This current research employed a qualitative approach utilizing a contextual paradigm with a multiple case study methodology.

Out of ten investigated deans in a public higher education institution in Malaysia, nine reported experiences of organizational stressor elements arising from higher authority. Three non-overlapping subthemes were systematically discovered.

Successful identification of these higher authority organizational stressors has implications for higher education management policies. Policies that reduce or eliminate these stressors may create a positive and progressive environment for deans and the higher education field.

This study will thus serve to promote a deeper understanding of higher authority organizational stressors encountered by higher education deans.

Two research questions are addressed: what are black female college students’ perceptions of current messages present on web sites about HIV/AIDS awareness and prevention?; and what messages do black female college students find culturally relevant to them, and why? Results indicate that these women perceive several communication barriers including lack of trust and unfamiliarity with information sources, stigma ascribed to HIV, as well as misconceptions and traditional values held by some in the black community and health institutions. HIV prevention messages are perceived as relevant if they exhibit qualities including interactive features. The paper aims to discuss these issues.

To understand black collegiate women as health information seekers, it is important to engage paradigms that allow researchers to make sense of how group members construct their content needs, what helps shape this construction, and the meaning derived from the consumption of the information, focus groups are an effective qualitative method for enabling collective discussion and interaction between research participants that facilitates the exploration of under-researched topics like HIV prevention as well as the language commonly used by respondents to describe HIV from a socio-cultural perspective. The research team conducted three focus groups to appraise current black female college students’ attitudes and perceptions of messages presented on HIV/AIDS prevention and awareness web sites

HIV prevention messages are perceived as relevant if they exhibit qualities including interactive features, practical advice using non-technical vocabulary, content authored and disseminated by familiar and trustworthy individuals and institutions, and risk related to individual behaviors rather than the demographic group. Implications of the findings and suggestions for future research on the design of health information systems are provided.

This research is based on a small sample size based on one region of the USA.

Health communication materials should also provide strategies for dispelling myths, and combating feelings of stigma, and mistrust. In addition, practical advice such as questions to ask physicians may help to produce positive and desirable outcomes as black women seek services from the healthcare system. The message itself must take into account a number of factors include short and simple messages, clean web pages, navigation structures that make information easy to find, comprehensive information all found in a single web site, and interactive features to facilitate discussion and sharing. In particular, with social media, women can also play a role in the creation and dissemination of health messages in multiple modalities including text, spoken word, still and moving images, and music.

“A major component of preventive health practice is the availability and provision of information regarding risks to health and promotional measures for enhancing the health status among this population” (Gollop, 1997, p. 142). However, as Dervin (2005) cautions, while information is necessary, it is insufficient to encourage behavior change. To combat the health disparities that differentially impact African-American women requires expertize and understanding from multiple perspectives. By providing insight into how black collegiate women perceive HIV prevention information needs, the women in the focus groups lend a necessary voice in the effort toward healthy equity through the creation of effective health interventions that will appeal to them.

The author seeks to create an online and socially connected experience characteristic of ongoing user input and active engagement in content development which targets the population. From a human-computer interaction viewpoint, the authors are seeking to avoid design divorced from context and meaning. In developing such an experience, the authors will need to triangulate the roles of culture, context, and design to reduce the content divide, yet amplify the notion of participatory web. Participatory web embodies a social justice movement to build web content from voices typically dampened in the discourse. It (re)shapes meaning, identity, and ecologies in the process of foci on particular social, health, and political causes (e.g. HIV/AIDS). Giving black women ownership over the creation of health information on the internet may improve the ability to provide targeted HIV prevention content that is culturally salient and more effective in reducing HIV infections in this community.

The study aims to define a research agenda for creating resource-efficient supply chains (RESCs) by identifying and analysing their key characteristics as well as future research opportunities.

We follow a systematic review method to analyse the literature and to understand RESC, taking a substantive theory approach. Our approach is grounded in a specific domain, the agri-food sector, because it is an intensive user of an extensive range of resources.

The review shows that works of literature has looked at the use of resources primarily from the environmental impact perspective. There is a need to explore whether or not and how logistics/supply chain decisions will affect the overall configuration of future food supply chains in an era of resource scarcity and depletion and what the trade-offs will be.

The paper proposes an agenda for future research in the area of RESC. The framework proposed along with the key characteristics identified for RESC can be applied to other sectors.

Our research should facilitate further understanding of the implications and trade-offs of supply chain decisions taken on the use of resources by supply chain managers.

The paper explores the interaction between supply chains and natural resources and defines the key characteristics of RESC.

In the architecture, engineering and construction (AEC) industry, technology developers have difficulties in fully understanding user needs due to the high domain knowledge threshold and the lack of effective and efficient methods to minimise information asymmetry between technology developers and AEC users. The paper aims to discuss this issue.

A synthetic approach combining domain knowledge and text mining techniques is proposed to help capture user needs, which is demonstrated using building information modelling (BIM) apps as a case. The synthetic approach includes the: collection and cleansing of BIM apps’ attribute data and users’ comments; incorporation of domain knowledge into the collected comments; performance of a sentiment analysis to distinguish positive and negative comments; exploration of the relationships between user sentiments and BIM apps’ attributes to unveil user preferences; and establishment of a topic model to identify problems frequently raised by users.

The results show that those BIM app categories with high user interest but low sentiments or supplies, such as “reality capture”, “interoperability” and “structural simulation and analysis”, should deserve greater efforts and attention from developers. BIM apps with continual updates and of small size are more preferred by users. Problems related to the “support for new Revit”, “import & export” and “external linkage” are most frequently complained by users.

The main contributions of this work include: the innovative application of text mining techniques to identify user needs to drive BIM apps development; and the development of a synthetic approach to orchestrating domain knowledge, text mining techniques (i.e. sentiment analysis and topic modelling) and statistical methods in order to help extract user needs for promoting the success of emerging technologies in the AEC industry.