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The purpose of this paper is to study heat and steam transfer in a vertical air gap and improve thermal protective performance of protective clothing under thermal radiation and hot steam.

An experiment-based model was introduced to analyze heat and moisture transfer in the vertical air gap between the protective clothing and human body. A developed test apparatus was used to simulate different air gap sizes (3, 6, 9, 12, 15, 18, 21 and 24 mm). The protective clothing with different air gap sizes was subjected to dry and wet heat exposures.

The increase of the air gap size reduced the heat and moisture transfer from the protective clothing to the skin surface under both heat exposures. The minimum air gap size for the initiation of natural convection in the dry heat exposure was between 6 and 9 mm, while the air gap size for the occurrence of natural convection was increased in the wet heat exposure. In addition, the steam mass flux presented a sharp decrease with the rising of the air gap size, followed by a stable state, mainly depending on the molecular diffusion and the convection mass transfer.

This research provides a better understanding of the optimum air gap under the protective clothing, which contributes to the design of optimum air gap size that provided higher thermal protection against dry and wet heat exposures.

This paper describes the finite element solution of conjugate heat transfer problems with and without the use of gap elements. Direct and iterative methods to incorporate gap elements into a general finite element program are presented, along with their advantages and disadvantages of the two gap element treatments in the framework of finite elements. The numerical performance of the iterative gap element treatment is discussed in detail in comparison with analytical solutions for both 2‐ and 3‐D gap conductance problems. Numerical tests show that the number of iterations depends on the non‐dimensional number Bi = hL/k, and it increases approximately linearly with Bi for Bi≥0.6. Here, for gap heat transfer problems, h is taken to be the inverse of the contact resistance. This conclusion holds true for both 2‐ and 3‐D problems, for both linear and quadratic elements and for both transient and steady state calculations. Further numerical results for conjugate heat transfer problems encountered in heat exchanger and micro chemical reactors are computed using the gap element approach, the direct numerical simulations and analytical solutions whenever solvable. The results reveal that for the standard heat exchanger designs, an accurate prediction of temperature distribution in the moving streams must take into consideration the radial temperature distribution and the accuracy of the calculations depends on the non‐dimensional number Bi = hR/2k. From gap element calculations, it is found that classical analytical solutions are valid for a heat transfer analysis of an exchanger system, only when Bi<0.1. This important point so far has been neglected in virtually all the textbooks on heat transfer and must be included to complete the heat transfer theory for heat exchanger designs. Results also suggest that for thermal fluids systems with chemical reactions such as micro fuel cells, the gap element approach yields accurate results only when the heat transfer coefficient that accounts for the chemical reactions is used. However, when these heat transfer coefficients are not available, direct numerical simulations should be used for an accurate prediction of the thermal performance of these systems.

The purpose of this paper is to provide the details of developments to research works in the distribution characteristics of the air gaps within firefighters’ clothing and research methods to evaluate the effect of air gaps on the thermal protective performance of firefighters’ clothing.

In this paper, the distribution of air gaps within firefighters’ clothing was first analyzed, and the air gaps characteristics were summarized as thickness, location, heterogeneity, orientation and dynamics. Then, the evaluation of the air gap on the thermal protective performance of fighters’ clothing was reviewed for both experimental and numerical studies.

The air gaps within clothing layers and between clothing and skin play an important role in determining the thermal protective performance of firefighters’ protective clothing. It is obvious that research works on the effects of actual air gaps entrapped in firefighters’ clothing on thermal protection are comparatively few in number, primarily focusing on static and uniform air gaps at the fabric level. Further studies should be conducted to define the characteristic of air gap, deepen the understand of mechanism of heat transfer and numerically simulate the 3D dynamic heat transfer in clothing to improve the evaluation of thermal protective performance provided by the firefighters’ clothing.

Air gaps within thermal protective clothing play a crucial role in the protective performance of clothing and provide an efficient way to provide fire-fighting occupational safety. To accurately characterize the distribution of air gaps in firefighters’ clothing under high heat exposure, the paper will provide guidelines for clothing engineers to design clothing for fighters and optimize the clothing performance.

This paper is offered as a concise reference for researchers’ further research in the area of the effect of air gaps within firefighters’ clothing under thermal exposure.

The vortex shedding from a rectangular cylinder improves the heat transfer rates. Introducing a ground effect in such a flow system alters the shedding frequency, which in turn enables to vary the cooling rates of the cylinder. In the present study a laminar flow passing over a rectangular cylinder with a ground effect is considered. The flow and energy equations are solved numerically using a control volume approach. Strouhal and Stanton number variations due to gap height are computed and the influence of Strouhal number on Stanton number variation behind the cylinder is examined. The study is extended to include the predictions of entropy generation in the solution domain. It is found that shedding frequency increases as gap height reduces and further reduction in gap height results in diminishing of vortex shedding, in which case confined flow is developed in the gap. Heat transfer rates improve when Strouhal number is maximum. In the case of confined flow situation, heat transfer rates enhance substantially in the region close to the top corner of the cylinder, in which case, non‐uniform cooling of the surface is resulted.

The extent to which means-tested transfers, social insurance, and tax credits fill the gap between a family's private resources and the poverty threshold is a periodic barometer of the social safety net. Using data on families from the Current Population Survey I examine how the level and composition of before- and after-tax and after-transfer poverty gaps changed in response to changes in the policy and economic landscapes over the past two decades. The estimates presented here indicate not only dramatic changes in the level and sources of income maintenance programs filling the poverty gap, but also dramatic changes in which demographic groups successfully fill the gap. From the peak-to-peak business-cycle years of 1979 to 1999, the fraction of the gap left unfilled among non-elderly families in poverty has expanded by 25 percent, while the unfilled gap has increased by 50 percent among single female-headed families, families headed by non-whites, and families residing in the Northeast. In a given year the poor in the South fill considerably less of the poverty gap with cash welfare, but make up for much of the shortfall with higher payments of food stamps, SSI, and SSDI. Over time the poor in all regions of the country have substituted SSI, SSDI, and the EITC for cash welfare. Indeed, by 1999 the unfilled gap for families with related children present would be one-fifth larger without the EITC. With the exception of married-couple families, this apparent rate of replacement of disability payments and tax credits for cash welfare is less than one for one, leaving most poor families, especially non-white families and single female-headed families, financially more vulnerable today than in previous decades.

The purpose of this paper is to perform the stimulation in order to examine the effects on the heat transfer coefficient and the flowfield properties at the vicinity of the gap due to variations in the width-to-depth ratio.

The governing equations were discreted by using the finite volume method, and based on pressure-velocity coupled algorithm, the heat transfer coefficients outside and inside the gaps, defined by the width-to-depth ratio of 1, 2/3, 1/2, 1/3 and 1/4, were obtained by the Fluent software.

The number of vortex inside the gap depends on the width-to-depth ratio, and the maximum value of the heat transfer coefficient emerges on the downstream surface.

The study gives a feasible method to simulate the flowfield and the heat transfer inside the gap, which will help the design of the thermal protection system for reentry vehicles.

The purpose of this paper is through a literature study and a study of the Saab offset cases to identify strategies to increase inter-organizational transfer capability.

This paper is based on a literature study and a study of three of Saab’s offset cases and Saab’s process for technology transfer.

This study has identified inter-organizational transfer strategies based on the importance of the hierarchy of decision-making and the change from capacity transfers to capability transfers in offset business. The type of performance goals set in the business agreement decides how to realize the transfer. The hierarchy of decision-making creates a need to align the understanding of the performance goals between the different parts of the organization, which affect the plans for how to transfer knowledge between the organizational as well as the individual levels. To reach the performance goals of the technology transfer, there needs to be a balance between the disseminative capability of the sender and the absorptive capability of the receiver.

This study is based on a single case within a relatively unique industry with an offset perspective and production transfers. Therefore, there is also a need for future studies to confirm the identified relationships within outsourcing/offset within other industries and other types of transfers.

A change from capacity transfers to capability transfers in both outsourcing/offshoring and offset business indicates that more research should be placed on the disseminative capacity of the sender. The literature review revealed that the disseminative capacity of the sender has been the subject of less research than the absorptive capacity of the receiver.

For training in a corporate setting transfer of training is essential. Yet time and again research shows transfer is a problem. Reflection on theory and years of practice as a trainer is the basis for this article. It aims to contribute to analysis and if possible to the solution of the persistent problem of transfer. First the concept of “frame” is illustrated; then the transfer problem is described in the form of challenges for trainer, trainee and organisation. The transfer frame is introduced, presenting transfer as a two‐way process. How can this view contribute to benefit transfer? Transfer may improve by closely connect the two contexts in which the trainee/employee functions. In the context of training there should be performance and the in context of work there should be learning. Training techniques creating “as if” situations are applicable in both contexts. An instruction like “evoke” may help the trainee/employee to operate successfully in the role of manager of his/her own transfer process. Further research is required to establish empirical evidence for or against the transfer effects of evocation strategies and “as if” techniques.

The purpose of this paper was to study laminar fluid flow and convective heat transfer in a conical gap at small conicity angles up to 4° for the case of disk rotation with a fixed cone.

In this paper, the improved asymptotic expansion method developed by the author was applied to the self-similar Navier–Stokes equations. The characteristic Reynolds number ranged from 0.001 to 2.0, and the Prandtl numbers ranged from 0.71 to 10.

Compared to previous approaches, the improved asymptotic expansion method has an accuracy like the self-similar solution in a significantly wider range of Reynolds and Prandtl numbers. Including radial thermal conductivity in the energy equation at small conicity angle leads to insignificant deviations of the Nusselt number (maximum 1.23%).

This problem has applications in rheometry to experimentally determine viscosity of liquids, as well as in bioengineering and medicine, where cone-and-disk devices serve as an incubator for nurturing endothelial cells.

The study can help design more effective devices to nurture endothelial cells, which regulate exchanges between the bloodstream and the surrounding tissues.

To the best of the authors’ knowledge, for the first time, novel approximate analytical solutions were obtained for the radial, tangential and axial velocity components, flow swirl angle on the disk, tangential stresses on both surfaces, as well as static pressure, which varies not only with the Reynolds number but also across the gap. These solutions are in excellent agreement with the self-similar solution.

The paper intends to identify the causes or gaps in transfer of managerial knowledge between academia and practitioners and to develop a framework that overcomes the gaps through knowledge management, information technology and human resource practices. The paper aims to suggest a strategic approach based on the knowledge transfer cycle.

The paper presents the development of a conceptual model based on existing research findings and conceptual models in the literature combined with the experience of academicians.

There has been very little transfer of research knowledge due to the inherent barriers in its creation, diffusion, adoption and utilization by practitioners. By enhancing the industry orientation of academicians and adopting systematic processes of review and dissemination, early adopters (practitioners) can experiment and learn to apply theoretical knowledge, which, when supported by institutional mechanisms, of human resource management, information technology and knowledge management (KM), can minimize or eliminate knowledge transfer gaps, leading to improved competitiveness and performance of the firm.

The framework has been developed from concepts of KM and transfer and learning and needs to be validated empirically.

The framework developed can guide researchers in their approach toward knowledge creation so that their output is adopted by industry and thus has value. Practitioner industries can develop practices based on the framework to enhance their ability to leverage academic knowledge for competitive advantage.

The paper would enable the framing of policies by higher education institutions and industry to facilitate more effective and efficient transfer of knowledge between researchers and practitioners, leading to enhanced organizational competitive advantage, which would benefit society.

The paper provides a framework based on the knowledge transfer cycle model for enhancing the effectiveness and efficiency of research knowledge adoption and utilization.