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帕金森病患者坐立速度的可调性

世界核心医学期刊文摘（神经病学分册） 2005年第8期1卷 29-30页

作者： Mak M.K.y. hui-chan c.w.y. 高中宝 Dept. of Rehabilitation Sciences Hong Kong Polytechnic UniversityHung Hom Hong Kong

Objective: To evaluate whether Parkinsonian patients could modify the speed of a sit-to-stand (STS) task to the same extent as that of healthy subjects. Met hods: Twenty Parkinsonian patients and 20 control subjects were instructed to st and up at a natural and fast speed. Kinematic data and kinetic data were recorde d. Results: Parkinsonian patients were significantly slower than healthy individ uals during STS at a natural speed. when required to perform STS task at a fast speed,these patients could increase both peak horizontal and vertical velocities of the task, by significantly increasing hip and ankle dorsiflexion torques and the rate of torque production, just as the control subjects did. In fact, no di fference was found for the percentage changes in both peak velocities and moveme nt time between the two groups, though similar between-group differences during STS at a natural speed still existed at a fast speed. conclusions: Parkinsonian patients had problems in generating adequate lower limb joint torques and in th e rate of torque production when performing STS at a natural ***, thes e patients were capable of increasing the speed of their STS with the same perce ntage changes as those of healthy subjects. Significance: The capability of Park insonian patients for increasing movement speed gives new insights to rehabilita tion strategy.

关键词：帕金森病可调性康复治疗健康受试者生成率背屈关节力矩动力学数据

功能性电刺激促进首次急性卒中患者下肢运动康复和行走能力:一项随机安慰剂对照试验

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世界核心医学期刊文摘（神经病学分册） 2005年第6期1卷 55-56页

作者： hui- chan c.w.y. Li L.S.w. 沈才飞 Dept. of Rehabilitation Sciences Hong Kong Polytechnic University Hung Hum Kowloon Hong Kong Dr.

Background and Purpose - The effectiveness of functional electrical stimulation (FES) has been investigated in chronic hemiplegia. The present study examines whether FES, given during acute stroke, was more effective in promoting motor recovery of the lower extremity and walking ability than standard rehabilitation alone. Methods - Forty- six subjects, 70.9± 8.0 years old and 9.2± 4.1 days after stroke, were assigned randomly to 1 of 3 groups receiving standard rehabilitation with FES or placebo stimulation or alone (control). FES was applied 30 minutes and placebo stimulation 60 minutes, 5 days per week for 3 weeks. Outcome measurements included composite spasticity score, maximum isometric voluntary contraction of ankle dorsi- flexors and planter- flexors, and walking ability. They were recorded before treatment, weekly during the 3- week treatment, and at week 8 after stroke. Results - No significant differences were found in the baseline measurements. After 3 weeks of treatment, there was a significant reduction in the percentage of composite spasticity score, and a significant improvement in the ankle dorsiflexion torque, accompanied by an increase in agonist electromyogram and a reduction in electromyogram cocontraction ratio in the FES group, when compared with the other 2 groups (P cts in the FES group were able to walk after treatment, and 84.6% of them returned home, in comparison with the placebo (53.3% ) and control (46.2% , P conclusions - Fifteen sessions of FES, applied to subjects with acute stroke plus standard rehabilitation, improved their motor and walking ability to the degree that more subjects were able to return to home.

关键词：功能性电刺激急性卒中下肢运动行走能力安慰剂对照康复治疗证实有效屈肌背侧收缩情况

Effect of terrain and building structures on the airflow in an airport

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第6期13卷 461-468页

作者： Dennis y. c. LEUNG w. y. LO w. y. cHOw P. w. chan Department of Mechanical Engineering The University of Hong Kong Hong Kong China Hong Kong Observatory Hong Kong China

The aim of this study was to perform computational fluid dynamics (cFD) simulations on the airflows at the Hong Kong International Airport (HKIA). In particular, the effects of hangar buildings and terrain were studied to explore the effects of turbulence on flying aircraft, especially during landing. The cFD simulation showed that significant differences in wind speeds may occur between the north and the south runways on the western part of the HKIA under typhoon conditions with a strong north to northwesterly wind. Simulation also showed that the hanger buildings between the two runways on the western side and the nearby terrain could be causing the observed difference in the wind speeds. The results also indicated that these obstacles could cause significant wind speed variations at the western end of the south runway. This may affect the operation of landing aircraft. The cFD results for a typical typhoon case were analyzed and found to match the wind data recorded by an aircraft landing that day.

关键词： computational fluid dynamics (cFD) Hong Kong International Airport (HKIA) Low-level wind effect Hangars Terrain

computational fluid dynamics simulation of the wind flow over an airport terminal building

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第6期11卷 389-401页

作者： chun-ho LIU Dennis y.c.LEUNG Alex c.S.MAN P.w.chan Department of Mechanical Engineering The University of Hong Kong Hong Kong Observatory

Turbulence in the wake generated by wind flow over buildings or obstacles may produce complex flow patterns in downstream *** include the recirculating flow and wind deficit areas behind an airport terminal building and their potential impacts on the aircraft landing on nearby runways.A computational fluid dynamics(cFD) simulation of the wind flow over an airport terminal building was performed in this study of the effect of the building wake on landing *** normal meteorological conditions,the studied airport terminal building causes limited effects on landing aircraft because most of the aircraft have already landed before entering the turbulent wake *** simulating the approach of a tropical cyclone,additional cFD sensitivity tests were performed to study the impacts of building wake under extreme meteorological *** was found that,in a narrow range of prevalent wind directions with wind speeds larger than a certain threshold value,a substantial drop in wind speed(>3.6 m/s) along the glide path of aircraft was observed in the building *** cFD results also showed that under the most critical situation,a drop in wind speed as large as 6.4 m/s occurred right at the touchdown point of landing aircraft on the runway,an effect which may have a significant impact on aircraft *** study indicated that a comprehensive analysis of the potential impacts of building wake on aircraft operations should be carried out for airport terminals and associated buildings in airfields to ensure safe aviation operation under all meteorological conditions and to facilitate implementation of precautionary measures.

关键词： Aviation safety Building aerodynamics computational fluid dynamics (cFD) k-e turbulence model Tropicalcyclone

Purge and trap method to determine alpha factors of VOc liquid-phase mass transfer coefficients

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chinese Science Bulletin 2000年第S1期45卷 76-79页

作者： S.c.Lee L.y.chan c.y.chan Department of civil & Structural Engineering The Hong Kong Polytechnic UniversityHong KongChina Correspondence should be addressed to Wang XinmingDepartment of Civil & Structural EngineeringThe Hong Kong Polytechnic UniversityHong KongChina Correspondence should be addressed to Wang XinmingDepartment of Civil & Structural EngineeringThe Hong Kong Polytechnic UniversityHong KongChina Correspondence should be addressed to Wang Xinming

A theoretical approach and laboratory practice of determining the alpha factors of volatile organic compound (VOc) liquid-phase mass transfer coefficients are present in this study. Using Purge & Trap concentrator, VOc spiked water samples are purged by high-purity nitrogen in the laboratory, the VOc liquid-phase mass transfer rate constants under the laboratory conditions are then obtained by observing the variation of VOcs purged out of the water with the purge time. The alpha factors of VOc liquid-phase mass transfer coefficients are calculated as the ratios of the liquid-phase mass transfer rate constants in real water samples to their counterparts in pure water under the same experimental conditions. This direct and fast approach is easy to control in the laboratory, and would benefit mutual comparison among researchers, so might be useful for the study of VOc mass transfer across the liquid-gas interface.

关键词： mass transfer coefficient purge and trap volatile organic compounds alpha factor.

comprehensive characterization of indoor airborne bacterial profile

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Journal of Environmental Sciences 2009年第8期21卷 1148-1152页

作者： P. L. chan P. H. F. yu y. w. cheng c. y. chan P. K. wong Department of Biology The Chinese University of Hong Kong Department of Applied Biology and chemical Technology The Hong Kong Polytechnic University Department of Microbiology The Chinese University of Hong Kong

This is the first detailed characterization of the airborne bacterial profiles in indoor environments. Two restaurants were selected for this study. Fifteen genera of bacteria were isolated from each restaurant and identified by three different bacterial identification systems including MIDI, Biolog and Riboprinter. The dominant bacteria of both restaurants were Gram-positive bacteria in which Micrococcus and Bacillus species were the most abundant. Most bacteria identified were representative species of skin and respiratory tract of human, and soil. Although the bacterial levels in these two restaurants were below the limit of the Hong Kong Indoor Air Quality Objective （HKIAQO） Level 1 standard （i.e., 〈 500 cfu/m^3）, the majority of these bacteria were opportunistic pathogens. These results suggested that the identity of airborne bacteria should also be included in the IAQ to ensure there is a safety guideline for the public.

关键词： airborne bacterial profile bacterial identification indoor air quality

Perception of Potential Health Risk of climate change and Utilization of Fans and Air conditioners in a Representative Population of Hong Kong

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International Journal of Disaster Risk Science 2020年第1期11卷 105-118页

作者： yang Gao Emily y.y.chan Holly c.y.Lam Aiwei wang Department of Sport and Physical Education Hong Kong Baptist UniversityHong KongChina collaborating centre for Oxford University and cUHK for Disaster and Medical Humanitarian Response The Jockey Club School of Public Health and Primary CareThe Chinese University of Hong KongHong KongChina

climate change, especially as reflected in heat waves, is a rising threat worldwide. Appropriate use of cooling devices can protect people from health impacts during a heat wave. A population-based telephone survey was conducted in a representative sample of residents in Hong Kong to investigate ownership and use of domestic cooling devices, identify correlates, and examine their associations with risk perception of potential health impact of climate change. More than 90% of the 1002 respondents owned and used cooling devices at home. The majority(57.7%) perceived the potential health risk of climate change at a high level. However, risk perception had no relationship with ownership and utilization of cooling devices. Old people(≥ 65 years), the low-educated, those with low income, and those with chronic diseases were more likely not to use air conditioners when feeling *** findings suggest that there are no signs showing people have taken more protective actions although half of respondents recognized climate change as a threat. Familial economic condition may be a major determinant in ownership and use of air conditioners at home. Old people and those with chronic diseases are at high risk of adverse exposure to climate change and therefore should be equipped with appropriate measures to use cooling devices.

关键词： climate change Domestic cooling device Heat wave health impact Hong Kong Risk perception

A MULTIPLE INTELLIGENT AGENT SySTEM FOR cREDIT RISK PREDIcTION VIA AN OPTIMIZATION OF LOcALIZED GENERALIZATION ERROR wITH DIVERSITy

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Journal of Systems Science and Systems Engineering 2007年第2期16卷 166-180页

作者： Daniel S. yEUNG wing w. y. NG Aki P. F. chan Patrick P. K. chan Michael FIRTH Eric c. c. TSANG Media and Life Science computing Laboratory Shenzhen Graduate School Harbin Institute of Technology Shenzhen 518055 China Department of computing Hong Kong Polytechnic University Hong Kong China Department of Finance and Insurance Lingnan University Hong Kong

company bankruptcies cost billions of dollars in losses to banks each year. Thus credit risk prediction is a critical part of a bank＇s loan approval decision process. Traditional financial models for credit risk prediction are no longer adequate for describing today＇s complex relationship between the financial health and potential bankruptcy of a company. In this work, a multiple classifier system （embedded in a multiple intelligent agent system） is proposed to predict the financial health of a company. In our model, each individual agent （classifier） makes a prediction on the likelihood of credit risk based on only partial information of the company. Each of the agents is an expert, but has limited knowledge （represented by features） about the company. The decisions of all agents are combined together to form a final credit risk prediction. Experiments show that our model out-performs other existing methods using the benchmarking compustat American corporations dataset.

关键词： credit rating business intelligence localized generalization error multiple classifier system feature grouping

Nitric oxide removal by wastewater bacteria in a biotrickling filter

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Journal of Environmental Sciences 2014年第3期26卷 555-565页

作者： Hejingying Niu Dennis y c Leung chifat wong Tong Zhang Mayngor chan Fred c c Leung Department of Mechanical Engineering The University of Hong Kong School of Biological Sciences The University of Hong Kong Department of civil Engineering The University of Hong Kong

Nitric oxide （NO） is one of the most important air pollutants in atmosphere mainly emitted from combustion source. A biotriclding filter was designed and operated to remove NO from an air stream using bacteria extracted from the sewage sludge of a municipal sewage treatment plant. To obtain the best operation conditions for the biotrickling filter, orthogonal experiments （L9（34）） were designed. Inlet oxygen concentration was found to be the most significant factor of the biotrickling filter and has a significant negative effect on the system. The optimal conditions of the biotrickling filter occurred at a temperature of 40℃, a pH of 8.0 and a chemical oxygen demand of 165 mg/L in the recycled water with no oxygen in the system. The bacteria sample was detected by DNA sequencing technology and showed 93%-98% similarity to Pseudomonas mendocina. Moreover, a full gene sequencing results indicated the bacterium was a brand new strain and named as P. mendocina DLHK. This strain can transfer nitrate to organic nitrogen. The result suggested the assimilation nitrogen process in this system. Through the isotope experimental analysis, two intermediate products （^15NO and ^15N2O） were found. The results indicated the denitrification function and capability of the biotrickling filter in removing NO.

关键词： NO reduction biotrickling filter orthogonal experiment Pseudomonas mendocina isotope labeling