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The purpose of this paper is to study the effects of dimple geometries and arrangements on the heat transfer enhancement in a dimple jacketed heat exchanger.

For the purpose of this paper, with the experimental validated numerical model, this paper carries out numerical simulations of both single dimples with different geometries and the whole dimple jacketed heat exchanger with different dimple arrangements. For a single dimple, its secondary vortex flow, temperature differences and the pressure drop performance for different geometries are analyzed. For the whole dimple jacketed heat exchanger, the heat transfer and pressure drop performances are investigated by comparing the no dimple, triangular and rectangular dimple arrangements.

Results show that dimples can improve the heat transfer efficiency compared with conventional jacketed heat exchanger, and specific geometries and arrangement of dimples for better heat transfer performance are figured out.

This paper considers both dimple geometries and arrangements, which can be useful for further applications in specific integrated devices or similar applications.

The aims of this study are to conduct a systematic review of public–private partnership (PPP) studies published from 2009 to 2019, to compare the results with Ke et al. (2009) who reviewed the PPP literature published from 1998 to 2008, and to trace the evolution of the PPP knowledge in the past two decades. This study also presents the possible directions that the PPP research may go towards in the future, arguably.

This study carried out a top journal-based search to identify the quality PPP articles published from 2009 to 2019. A total of 12 top-tier construction journals were systematically searched in the database of web of science (WOS), from which 279 PPP articles were identified for review.

The number of the identified articles, the titles of the journals, institutions, the most cited papers, and prevalent research methods were analyzed and compared. The existing PPP studies in construction journals were classified into seven streams. Through analysis of the PPP research status and gaps, five future research directions were revealed.

This study contributes to the current body of knowledge by revealing the research trend of PPP from 2009 to 2019. It presents the change of PPP development trend in the past decade through comparison with Ke et al. (2009). It also reveals the major research streams and points out the directions that the PPP research may go towards in the future. Moreover, this study is helpful to the practice as well. It can enhance the practitioners' understanding of the PPP development in the past decade. In addition, it identified the research institutions contributing the most in the area of PPP, which may serve as valuable reference for practitioners to locate the best institutions for consultancy or collaboration.

The purpose of this paper is to numerically investigate the heat transfer performance of aviation kerosene flowing in smooth and enhanced tubes with asymmetric fins at supercritical pressures and to reveal the effects of several key parameters, such as mass flow rate, heat flux, pressure and inlet temperature on the heat transfer.

A CFD approach is taken and the strong variations of the thermo-physical properties as the critical point is passed are taken into account. The RNG k-ε model is applied for simulating turbulent flow conditions.

The numerical results reveal that the heat transfer coefficient increases with increasing mass flow rate and inlet temperature. The effect of heat flux on heat transfer is more complicated, while the effect of pressure on heat transfer is insignificant. The considered asymmetric fins have a small effect on the fluid temperature, but the wall temperature is reduced significantly by the asymmetric fins compared to that of the corresponding smooth tube. As a result, the asymmetric finned tube leads to a significant heat transfer enhancement (an increase in the heat transfer coefficient about 23-41 percent). The enhancement might be caused by the re-development of velocity and temperature boundary layers in the enhanced tubes. With the asymmetric fins, the pressure loss in the enhanced tubes is slightly larger than that in the smooth tube. A thermal performance factor is applied for combined evaluation of heat transfer enhancement and pressure loss.

The asymmetric fins also caused an increased pressure loss. A thermal performance factor ? was used for combined evaluation of heat transfer enhancement and pressure loss. Results show that the two enhanced tubes perform better than the smooth tube. The enhanced tube 2 gave better overall heat transfer performance than the enhanced tube 1. It is suggested that the geometric parameters of the asymmetric fins should be optimized to further improve the thermal performance and also various structures need to be investigated.

The asymmetric fins increased the pressure loss. The evaluation of heat transfer enhancement and pressure loss Results showed that the two enhanced tubes perform better than the smooth tube. It is suggested that the geometric parameters of the asymmetric fins should be optimized to further improve the thermal performance and also various structures need to be investigated to make the results more engineering useful.

The paper presents unique solutions for thermal performance of a fluid at near critical state in smooth and enhanced tubes. The findings are of relevance for design and thermal optimization particularly in aerospace applications.

By use of equivalence operators δ_i and semiequivalence operators ε_i, studies the clustering problems of complex systems. Presents the δ (1,3) disconnection principle, dual‐transformation principle for analysing and operating complex systems and large‐scale systems. Discusses interconnectivity and disconnectivity of complex systems. Presents some related theorems. Discusses hierarchy of systems according to the pansystems clustering approach proposed.

Building on the resource- and knowledge-based views, this paper aims to explore how coopetition affects radical innovation and the roles of knowledge structure and external knowledge integration in the relationship between coopetition and radical innovation.

This study proposes a research model to examine the mediating role of external knowledge integration on the coopetition-radical innovation link, where the mediation is moderated by the firm’s knowledge structure (including component knowledge and architectural knowledge). The authors use regression and bootstrapping to test the proposed model with survey data from 241 Chinese technology firms.

This study finds that coopetition positively affects radical innovation and the effect is fully mediated by external knowledge integration. Additionally, component knowledge negatively moderates the coopetition-external knowledge integration link and architectural knowledge positively moderates this relationship. Further, the mediating effect of external knowledge integration is also moderated by component knowledge and architectural knowledge.

Firms should engage in coopetition to promote radical innovation. Further, it is necessary for firms to appropriately manage coopetition according to their internal knowledge structure.

This study explains why scholars have different ideas about the relationship between coopetition and radical innovation by exploring the mediating role of external knowledge integration and the moderating effect of knowledge structure. Firms possess increased possibilities for knowledge leakage and partner opportunism with high levels of component knowledge, which will reduce the positive effect coopetition on external knowledge integration; thus, they are less likely to realize radical innovation. Instead, firms possess increased opportunities for resource sharing with high levels of architectural knowledge, thus improving the positive effect coopetition on external knowledge integration and they are more likely to achieve radical innovation.

Miniature loop heat pipes (MLHPs) are highly efficient passive heat transfer devices, which have considerable advantages over conventional heat pipes. Currently, miniature LHPs with ammonia and water as working fluids have been developed and utilized in electronics cooling within temperature range of 50°C-70°C at any orientation in 1-g conditions.

The authors studied the standard procedure for the development of bi-porous nickel wicks and their characterization. Three different shaped nickel powders were studied, and best fitting nickel powder for electronics cooling application was reported. The manufacturing of bi-porous wick structures was analyzed with parameters such as porosity, permeability, capillary pressure and effective thermal conductivity for efficient performance of MLHP.

The study investigated the sintering process for number of samples to identify effective sample for the particular application. It is found that carbonyl nickel powder (type 287) with particle size of 2.6-3.3 µm gives promising results. Permeability and porosity were found to be highest in this case.

It is found that carbonyl nickel powder type with particle size gives promising results. Permeability and porosity was found to be highest in this case.

Although scholars in strategic management have identified innovating and exit as firms’ two sequential strategic responses to long-run crisis, the potential interdependency has yet remained implicit. Specifically, in the context of Chinese Privately Owned Enterprises (POEs), this study investigates the interrelationship of these two strategic responses during long-run crisis. Building on resource redeployment perspective, the authors propose that firms tend to simultaneously leverage innovating and exit responses.

The authors use the data from the 2010 Chinese POEs survey to verify how firms in the long-term crisis made strategic responses after the 2008 financial crisis. Besides, the authors utilize Probit regressions as the basic analysis and further employ bivariate Probit regressions to conduct robustness tests.

This study provides empirical evidence confirming that firms in the long-run period of the crisis tend to adopt both exit and innovating strategies at the same time, that is, the strategy of resource redeployment. Moreover, this study further finds that government subsidies, the degree of marketization and firm’s organizational capability could all accentuate the decision-making of firms’ resource redeployment.

The authors thus contribute to the study of strategic responses to crisis in strategic management by dynamically find out the interdependency of two responses and enrich the research on resource redeployment perspective by identifying three influential positive antecedents, adding to the ongoing investigation on positive drivers of resource redeployment.

There is significant amount of literature tackling different issues related to the port industry. The present chapter focuses on a single business unit of seaports aiming at the documentation of works related to container terminals.

An effort to review, collect and present the majority of the works present in the last 30 years, between 1980 and 2010, has been made in order to picture the problems dealt and methods used by the authors in the specific research field. To facilitate the reader, studies have been grouped under five categories of addressed problems (productivity and competitiveness, yard and equipment utilization, equipment scheduling, berth planning, loading/unloading) and four modelling methodologies (mathematics and operations research, management and economics, simulation, stochastic modelling).

The analysis shows that most works focus on productivity and competitiveness issues followed by yard and equipment utilisation and equipment scheduling. In reference to the methodologies used managerial and economic approaches lead, followed by mathematics and operations research.

In reference to future research, two fields have been identified where there is scope of significant contribution by the academic community: container terminal security and container terminal supply chain integration.

The present chapter provides the framework for researchers in the field of port container terminals to picture the so far works in this research area and enables the identification of gaps at both research question and methodology level for further research.

This paper aims to construct rental housing indices and identify market segmentation for more effective property-management strategies.

The hedonic model was employed to construct the rental indices. Using the k-means++ and REDCAP (Regionalisation with Dynamically Constrained Agglomerative Clustering and Partitioning) approaches, the authors conducted clustering analysis and identified different market segmentation. The empirical study relied on the database of 80,212 actual rental transactions in Beijing, China, spanning 2016–2018.

Rental housing market segmentation may distribute across administrative boundaries. Properly segmented indices could provide a better account for the heterogeneity and spatial continuity of rental housing and as well be crucial for effective property management.

Residential rent might not only vary over space but also interplays with housing price. It would be worth studying how the rental market functions together with the owner-occupied sector in the future.

Residential rental indices are of great importance for policymakers to be able to evaluate housing policies and for property managers to implement competitive strategies in the rental market. Their constructions largely depend on the analysis of market segmentation, a trade-off between housing spatial heterogeneity and continuity.

This paper fills the gap in knowledge concerning segmented rental indices construction, particularly in China. The spatial constrained clustering approach (REDCAP) was also initially introduced to identify regionalised market segmentation due to its superior performance.

With the fierce competition in a knowledge economy, knowledge-intensive enterprises (KIEs) make technological progress in their catching-up processes through implementing product innovation and process innovation. In this study, the aim is to understand the determinants of enterprise innovation type in China's catch-up environment. Further, this paper intends to deal with two related questions. First, what effect does the internal knowledge base have on KIEs' technology innovation activities? Second, considering the technology gap and technology development speed, what are the different impacts of the knowledge base on the type of technology innovation activities?

This paper collected data from 212 KIEs in China through a two-stage questionnaire survey, combined with statistical data for research. The hypothesis was tested by regression analysis. Specifically, descriptive statistics and regression analysis are introduced to test the hypothetical relationship between the knowledge base and technology innovation. Meanwhile, multiple regression is used to test whether there is any difference in the influence of technology gap and technology development speed on enterprise knowledge base and technology innovation. Finally, the corresponding robustness tests are done.

This study finds that in a sample of Yangtze River Delta KIEs, firms' knowledge base influences innovation types. Specifically, the knowledge base width (KBW) and knowledge base depth (KBD) positively influence process innovation, and KBD positively affects product innovation. Regarding the effects of catch-up context factors on KIEs’ innovation choice, a wide technology gap tends to positively influence product innovation in industries with high levels of KBW. Moreover, when technology development speed is high, its potential positive influence on process innovation will be more significant for industries with deeper knowledge bases.

This paper fills the research gap that existing studies ignore the relationship between types of technology innovation and knowledge base dimensions, especially for KIEs. First, this paper deepens the understanding of the impact mechanism of KIEs' existing knowledge base on innovation activities; the unique use of resources by enterprises is the basis of enterprises' competitive advantage and will become enterprises' competitive advantage. Second, this study indicates that against different backdrops of technology gap and technology development speed, enterprises with different knowledge bases will adopt different types of technology innovation activities. Third, this paper shows that a wider technology gap provides broader innovation space, so the technology gap plays a pulling role in KBW and product innovation, thus pushing forward enterprises' technological catch-up.