A Review of Fin - and - Tube Heat Exchangers in Air - conditioning Applications

Robert Yie-Zu Hu,Chi-Chuan Wang 대한설비공학회 2005 대한설비공학회 강연회 및 기타간행물 Vol.- No.-

A Review of Fin-and-Tube Heat Exchangers in Air-Conditioning Applications

Hu, Robert,Wan, Chi-Chuan The Society of Air-Conditioning and Refrigerating 2007 International Journal Of Air-Conditioning and Refr Vol.15 No.3

This study presents a short overview of the researches in connection to the fin-and-tube heat exchangers with and without the influence of dehumidification. Contents of this review article include the data reduction method, performance data, updated correlations, and the influence of hydrophilic coating for various enhanced fin patterns. This study emphasizes on the experimental researches. Performance of both sensible cooling and dehumidifying conditions are reported in this review article.

A Review of Fin-and-Tube Heat Exchangers inAir-Conditioning Applications

Robert Hu,Chi-Chuan Wang 대한설비공학회 2007 International Journal Of Air-Conditioning and Refr Vol.15 No.3

From Specialisation to Diversification in Science and Technology Parks

Robert Hassink,Xiaohui Hu 세계과학도시연합 2012 World Technopolis Review Vol.1 No.1

Science and technology parks have been popular among policy-makers at several spatial levels to promote innovation and economic growth of certain localities. However, this mainly property-led policy tool has been criticised for two reasons. First, it often failed to successfully support regional networking and technology transfer to regional firms. Only unplanned science and technology parks, such as Silicon Valley, seem to have been successfully fostering regional networking and technology transfer which has led, in turn, to the development of competitive innovative clusters. Secondly, it has too often bet on the same horses and become too specialised in the same fields, such as in micro-electronics or in biotechnology. This specialisation has been theoretically supported by the cluster concept. It has led to both a zero sum game of competition between locations as well as potentially negative path dependence and lock-ins. This paper suggests increasingly supporting diversification in science and technology parks by bringing together hitherto unconnected technologies. Several recently discussed concepts could be used to support diversification, such as related variety (Frenken et al. 2007), regional branching (Boschma and Frenken 2011), regional innovation platforms (Harmaakorpi et al. 2011) and transversality (Cooke 2011).

Bending of steel fibers on partly supported elastic foundation

Hu, Xiao Dong,Day, Robert,Dux, Peter Techno-Press 2001 Structural Engineering and Mechanics, An Int'l Jou Vol.12 No.6

Fiber reinforced cementitious composites are nowadays widely applied in civil engineering. The postcracking performance of this material depends on the interaction between a steel fiber, which is obliquely across a crack, and its surrounding matrix. While the partly debonded steel fiber is subjected to pulling out from the matrix and simultaneously subjected to transverse force, it may be modelled as a Bernoulli-Euler beam partly supported on an elastic foundation with non-linearly varying modulus. The fiber bridging the crack may be cut into two parts to simplify the problem (Leung and Li 1992). To obtain the transverse displacement at the cut end of the fiber (Fig. 1), it is convenient to directly solve the corresponding differential equation. At the first glance, it is a classical beam on foundation problem. However, the differential equation is not analytically solvable due to the non-linear distribution of the foundation stiffness. Moreover, since the second order deformation effect is included, the boundary conditions become complex and hence conventional numerical tools such as the spline or difference methods may not be sufficient. In this study, moment equilibrium is the basis for formulation of the fundamental differential equation for the beam (Timoshenko 1956). For the cantilever part of the beam, direct integration is performed. For the non-linearly supported part, a transformation is carried out to reduce the higher order differential equation into one order simultaneous equations. The Runge-Kutta technique is employed for the solution within the boundary domain. Finally, multi-dimensional optimization approaches are carefully tested and applied to find the boundary values that are of interest. The numerical solution procedure is demonstrated to be stable and convergent.

From Specialisation to Diversification in Science and Technology Parks

Hassink, Robert,Hu, Xiaohui World Technopolis Association 2012 World Technopolis Review Vol.1 No.1

Science and technology parks have been popular among policy-makers at several spatial levels to promote innovation and economic growth of certain localities. However, this mainly property-led policy tool has been criticised for two reasons. First, it often failed to successfully support regional networking and technology transfer to regional firms. Only unplanned science and technology parks, such as Silicon Valley, seem to have been successfully fostering regional networking and technology transfer which has led, in turn, to the development of competitive innovative clusters. Secondly, it has too often bet on the same horses and become too specialised in the same fields, such as in micro-electronics or in biotechnology. This specialisation has been theoretically supported by the cluster concept. It has led to both a zero sum game of competition between locations as well as potentially negative path dependence and lock-ins. This paper suggests increasingly supporting diversification in science and technology parks by bringing together hitherto unconnected technologies. Several recently discussed concepts could be used to support diversification, such as related variety (Frenken et al. 2007), regional branching (Boschma and Frenken 2011), regional innovation platforms (Harmaakorpi et al. 2011) and transversality (Cooke 2011).

Income and Education Inequalities in Brain and Central Nervous System Cancer Incidence in Canada: Trends over Two Decades

Alysha Roberts,Min Hu,Mohammad Hajizadeh 대한암예방학회 2021 Journal of cancer prevention Vol.26 No.2

The socioeconomic gradient of brain and central nervous system (CNS) cancer incidence in Canada is poorly understood. This study aimed to measure socioeconomic inequalities in brain and CNS cancer incidence in Canada from 1992 to 2010. Using a unique census division level dataset (n = 280) pooled from the Canadian Cancer Registry (CCR), the Canadian Census of Population and the National Household Survey, we measured brain and CNS cancer incidence in Canada. The age-adjusted concentration index (C) was used to measure income- and education-related inequalities in brain and CNS cancers in Canada, and for men and women, separately. Time trend analyses were conducted to examine the changes in socioeconomic inequalities in brain and CNS cancers in Canada over time. The results indicated that the crude brain and CNS cancer incidence increased from 7.29 to 8.17 per 100,000 (annual percentage change: 0.70) over the study period. The age-adjusted C results suggested that the brain and CNS cancer incidence was not generally significantly different for census division of different income and educational levels. There was insufficient evidence to support changes in income and education-related inequalities over time. Since the incidence of brain and CNS cancers in Canada showed no significant association with socioeconomic status, future cancer control programs should focus on other risk factors for this cancer subset. Key Words Social inequalities, Brain neoplasms, Central nervous system neoplasms, Incidence, Canada

TRAF3 regulates the effector function of regulatory T cells and humoral immune responses

( Jae Hoon Chang ),( Hongbo Hu ),( Jin Jin ),( Nahum Puebla Osorio ),( Yichuan Xiao ),( Brian E Gilbert ),( Robert Brink ),( Stephen E Ullrich ),( Shao Cong Sun ) 영남대학교 약품개발연구소 2014 영남대학교 약품개발연구소 연구업적집 Vol.24 No.0

Regulatory T cells (Treg cells) control different aspects of immune responses, but how the effector functions of Treg cells are regulated is incompletely understood. Here we identified TNF receptor-associated factor 3 (TRAF3) as a regulator of Treg cell function. Treg cell-specific ablation of TRAF3 impaired CD4 T cell homeostasis, characterized by an increase in the Th1 type of effector/memory T cells. Moreover, the ablation of TRAF3 in Treg cells resulted in increased antigen-stimulated activation of follicular T helper cells (TFH cells), coupled with heightened formation of germinal centers and production of high-affinity IgG antibodies. Although the loss of TRAF3 did not reduce the overall frequency of Treg cells, it attenuated the antigen-stimulated production of follicular Treg cells (TFR cells). TRAF3 signaling in Treg cells was required to maintain high level expression of inducible co-stimulator (ICOS), which in turn was required for TFR cell generation and inhibition of antibody responses. These findings establish TRAF3 as a mediator of Treg cell function in the regulation of antibody responses and suggest a role for TRAF3 in mediating ICOS expression in Treg cells.

Wind Effects on Tall Buildings with a Porous Double-Skin Façade

Shengyu Tian,Cassandra Brigden,Caroline Kingsford,Gang Hu,Robert Ong,K.C.S. Kwok Council on Tall Building and Urban Habitat Korea 2022 International journal of high-rise buildings Vol.11 No.4

Double-Skin Facades (DSF) on tall buildings are becoming increasingly common in urban environments due to their ability to provide architectural merit, passive design, acoustic control and even improved structural efficiency. This study aims to understand the effects of porous DSF on the aerodynamic characteristics of tall buildings using wind tunnel tests. High Frequency Force Balance and pressure tests were performed on the CAARC standard tall building model with a variable porous DSF on the windward face. The introduction of a porous DSF did not adversely affect the overall mean forces and moments experienced by the building, with few differences compared to the standard tall building model. There was also minimal variation between the results for the three porosities tested: 50%, 65% and 80%. The presence of a full-height porous DSF was shown to effectively reduce the mean and fluctuating wind pressure on the side face of the building by about 10%, and a porous DSF over the lower half height of the building was almost as effective. This indicates that the porous DSF could be used to reduce the design load on cladding and fixtures on the side faces of tall buildings, where most damage to facades typically occurs.

A Comparison Study between Convex-Louver , Wavy , and Plain Fin-and-Tube Heat Exchangers

C. C. Wang,Y. Z. Robert Hu,Y. M. Tsai 대한기계학회 1998 Heat transter conference Vol.6 No.1