检索结果-南通市图书馆

An Adaptive Nonsingular Fast Terminal Sliding Mode Control for Yaw Stability Control of Bus Based on STI Tire Model

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2021年第4期34卷 182-195页

作者： Xiaoqiang Sun Yujun Wang Yingfeng Cai Pak kin wong Long Chen Automotive Engineering Research Institute Jiangsu UniversityZhenjiang 212013China Department of Electromechanical Engineering University of MacaoTaipaMacaoChina State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China

Due to the bus characteristics of large quality,high center of gravity and narrow wheelbase,the research of its yaw stability control(YSC)system has become the focus in the field of vehicle system ***,the tire nonlinear mechanical properties and the effectiveness of the YSC control system are not considered carefully in the current *** this paper,a novel adaptive nonsingular fast terminal sliding mode(ANFTSM)control scheme for YSC is proposed to improve the bus curve driving stability and safety on slippery ***,the STI(Systems Technologies Inc.)tire model,which can effectively reflect the nonlinear coupling relationship between the tire longitudinal force and lateral force,is established based on experimental data and firstly adopted in the bus YSC system *** this basis,a more accurate bus lateral dynamics model is built and a novel YSC strategy based on ANFTSM,which has the merits of fast transient response,finite time convergence and high robustness against uncertainties and external disturbances,is ***,to solve the optimal allocation problem of the tire forces,whose objective is to achieve the desired direct yaw moment through the effective distribution of the brake force of each tire,the robust least-squares allocation method is *** verify the feasibility,effectiveness and practicality of the proposed bus YSC approach,the TruckSim-Simulink co-simulation results are finally *** co-simulation results show that the lateral stability of bus under special driving conditions has been significantly *** research proposes a more effective design method for bus YSC system based on a more accurate tire model.

关键词： Bus Yaw stability control Sliding mode control STI tire model Co-simulation

Highly active antiretroviral therapy per se decreased mortality and morbidity of advanced human immunodeficiency virus disease in Hong Kong

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2005年第16期118卷 1338-1345页

作者： CHAN Chi-wai CHENG Lai-sim CHAN wai-kit wong Ka-hing Integrated Treatment Centre Department of Health Hong Kong China

Background Morbidity and mortality of advanced human immunodeficiency virus infection （HIV） have declined in Western industrialized countries since the availability of highly active antiretroviral therapy （HAART）. It is unclear if this has also happened in Hong Kong. Methods We studied a retrospective cohort of patients with advanced HIV disease in Hong Kong, China. First, the mortality of advanced HIV disease per year was calculated for the decade 1993 to 2002, both annually and according to patient observation before and after 1997. Second, the event rates were estimated for the clinical end points of acquired immune deficiency syndrome （AIDS） and death. Univariate and multivariate analyses were then performed to identify associated factors. Results The crude mortality of advanced HIV disease declined from 10. 8 - 30. 4 per 100 patients during 1993 - 1996, to 0. 8 - 6. 9 per 100 patients during 1997 - 2002. A rate ratio of 4. 04 （95% CI, 2. 52 - 6. 47） was evident for those observed in 1993 - 1996, compared to those in 1997 - 2002. In a multivariate analysis where calendar period was adjusted, use of＇highly active antiretroviral therapy was associated with rate ratios of 0. 13 （95% CI, 0. 05 -0. 33） for death after AIDS, 0. 08 （95% CI, 0. 04 -0. 19） for AIDS after a CD4 cell count 〈200/μ1, and 0.21 （95% CI, 0.07 -0.67） for death after CD4 cell count 〈200/μl. In the same analysis, calendar period ceased to be a significant factor after adjustment for use of HAART. Conclusions The mortality and morbidity of advanced human immunodeficiency virus disease have declined in Hong Kong. This improved prognosis was attributable to the use of highly active antiretroviral therapy.

关键词： highly active antiretroviral therapy mortality· morbidity acquired immunodeficiency syndrome

Successful conservative management of Class III iatrogenic aortic dissection

在线全文

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2018年第3期15卷 235-237页

作者： wai kin Chi Gary Tse Bryan PY Yan Department of Medicine and Therapeutics Faculty of Medicine The Chinese University of Hong Kong Hong Kong China Division of Cardiology Prince of Wales Hospital Shatin Hong Kong China Li Ka Shing Institute of Health Sciences Faculty of Medicine The Chinese University of Hong Kong Hong Kong China

Iatrogenic aortic dissection (IAD) is a rare complication of percutaneous coronary intervention (PCI) with an estimated incidence of 0.02%-0.04%. IAD occurs more frequently in the setting of urgent PCI for acute myocardial infarction (AMI) (0.19%) than for elective procedures (0.01%).[1] The mortality risk associated with IAD is high (16%) and is comparable to that for spontaneous aortic dissection (16%). Urgent surgery is the treatment of choice for extensive dissection or hemodynamic instability. In this report, we present a case of severe IAD that was managed conservatively with good clinical outcome.

关键词：大动脉解剖治疗管理医生 III 保守总线标准

Optical coherence tomography-guided percutaneous transluminal angioplasty in renal artery fibromuscular dysplasia

在线全文

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2020年第3期17卷 173-174页

作者： wai kin Chi Tan Guang Ming Bryan P Yan Division of Cardiology Department of Medicine and TherapeuticsPrince of Wales Hospitalthe Chinese University of Hong KongHong KongChina

A 40-year-old woman was referred for resistant hypertension despite three anti-hypertensive medications including a diuretic at maximum tolerated *** has no family history of fibromuscular dysplasia(FMD).Contrast-enha... 详细信息

关键词： Fibromuscular dysplasia Optical coherence tomography Renal artery stenosis

Model Checking for a General Linear Model with Nonignorable Missing Covariates

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2012年第1期28卷 99-110页

作者： Zhi-hua SUN wai-Cheung IP Heung wong School of Mathematical sciences Graduate University of Chinese Academy of SciencesBeijing 100049China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Department of Applied Mathematics Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

In this paper, we investigate the model checking problem for a general linear model with nonignorable missing covariates. We show that, without any parametric model assumption for the response probability, the least squares method yields consistent estimators for the linear model even if only the complete data are applied. This makes it feasible to propose two testing procedures for the corresponding model checking problem： a score type lack-of-fit test and a test based on the empirical process. The asymptotic properties of the test statistics are investigated. Both tests are shown to have asymptotic power 1 for local alternatives converging to the null at the rate n-r, 0 ≤ r 〈 1/2. Simulation results show that both tests perform satisfactorily.

关键词： general linear model model checking nonignorable missing covariates sensitivity analysis

An unusual case of hypereosinophilic syndrome and disseminated intravascular coagulation

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2005年第18期118卷 1582-1584页

作者： YEUNG Tok-fai LAU Siu-wah wong kin Department of Medicine and Geriatrics Our Lady of Maryknoll Hospital Hong Kong ChinaDepartment of Medicine and Geriatrics Our Lady of Maryknoll Hospital Hong Kong China Department of Medicine and Geriatrics Our Lady of Maryknoll Hospital Hong Kong China

Idiopathic hypereosinophilic syndrome （HES） is a heterogeneous disorder characterized by hypereosinophilia and organ damage which affects men more commonly than women （9：1）. The disease can be detected incidentally, but more often presents either insidiously or acutely with cardiac, neurological, cutaneous, pulmonary or gastro- intestinal manifestations, with cardiac involvement being a major cause of morbidity and morality in patients. 1.2 Although a major mechanism of tissue damage in HES is due to thromboembolism,3 fullblown disseminated intravascular coagulation （DIC） is apparently rare. This paper describes a man who presented acutely with life-threatening DIC complicating HES and its management, the first Chinese case reported in the literature.

关键词： hypereosinophilic syndrome·disseminated intravascular syndrome·low molecular weight heparin

Ignition Pattern Analysis for Automotive Engine Trouble Diagnosis Using Wavelet Packet Transform and Support Vector Machines

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2011年第5期24卷 870-878页

作者： VONG Chi-man wong Pak-kin TAM Lap-mou ZHANG Zaiyong Department of Computer and Information Science Faculty of Science and Technology University of Macao Macao China Department of Electromechanical Engineering Faculty of Science and Technology University of Macao Macao China

Engine spark ignition is an important source for diagnosis of engine *** on the waveform of the ignition pattern,a mechanic can guess what may be the potential malfunctioning parts of an engine with his/her experience and ***,this manual diagnostic method is imprecise because many spark ignition patterns are very ***,a diagnosis needs many trials to identify the malfunctioning *** the mechanic needs to disassemble and assemble the engine parts for *** tackle this problem,an intelligent diagnosis system was established based on ignition ***,the captured patterns were normalized and *** wavelet packet transform（WPT） was employed to extract the representative features of the ignition ***,a classification system was constructed by using multi-class support vector machines（SVM） and the extracted *** classification system can intelligently classify the most likely engine fault so as to reduce the number of diagnosis *** results show that SVM produces higher diagnosis accuracy than the traditional multilayer feedforward neural *** is the first trial on the combination of WPT and SVM to analyze ignition patterns and diagnose automotive engines.

关键词： automotive engine ignition pattern diagnosis pattern classification wavelet packet transform support vector machines.

ABC/2 formula for"bedside"postoperative pneumocephalus volume measurement

在线全文

学校读者我要写书评

暂无评论

Chinese Neurosurgical Journal 2022年第4期8卷 284-291页

作者： David Yuen Chung Chan Eric Yuk Hong Cheung Ka Ho Hui Cecelia Mei Sze Leung Stephanie Chi Ping Ng wai Kit Mak George Kwok Chu wong Tat Ming Danny Chan wai Sang Poon Division of Neurosurgery Department of SurgeryFaculty of MedicinePrince of Wales HospitalThe Chinese University of Hong KongHong KongSARChina

Background:Postoperative pneumocephalus is associated with a higher risk of recurrence of chronic subdural hematoma(cSDH).However,there is no verified simple way to measure the pneumocephalus volume at the bedside for daily clinical *** ABC/2 method was shown to be a simple and reliable technique to estimate volumes of intracranial lesions,such as intracranial *** study aims to evaluate the accuracy of the ABC/2 formula in estimating volumes of pneumocephalus,as compared to the gold standard with computer-assisted volumetric ***:A total of 141 postoperative computed tomographic(CT)brain scans of cSDH patients with burr-hole drainage were *** volume was measured independently by both the ABC/2 formula and the computer-assisted volumetric *** the computer-assisted measurement,the volume of the air was semiautomatically segmented and calculated by computer *** regression was used to determine the correlation between the ABC/2 method and computer-assisted ***:The postoperative pneumocephalus volume after bilateral burr-hole drainage was significantly larger than that of unilateral burr-hole drainage(29.34 ml versus 12.21 ml,p<0.001).The estimated volumes by the formula ABC/2 significantly correlated to the volumes as measured by the computer-assisted volumetric technique,with r=0.992(p<0.001).The Pearson correlation coefficient is very close to 1,which signifies a very strong positive correlation,and it is statistically ***:An excellent correlation is observed between the ABC/2 method and the computer-assisted *** study verified that the ABC/2 method is an accurate and simple"bedside"technique to estimate pneumocephalus volume.

关键词： ABC/2 Chronic subdural haematoma Burr-hole Pneumocephalus

Application of PCR and real-time PCR for monitoring cyanobacteria, Microcystis spp. and Cylindrospermopsis raciborskii in Macao freshwater reservoir

在线全文

学校读者我要写书评

暂无评论

Frontiers of Earth Science 2014年第2期8卷 291-301页

作者： Weiying ZHANG Inchio LOU wai kin UNG Yijun KONG Kai Meng MOK Department of Civil and Environmental Engineering Faculty of Science and Technology University of Macao Macao SAR China Laboratory & Research Center Macao Water Co. Ltd. Macao SAR China

Freshwater algal blooms have become a growing concern world-wide. They are caused by a high level ofcyanobacteria, predominantly Microcystis spp. and Cylindrospermopsis raciborskii, which can produce microcystin and cylindrospermopsin, respectively. Longtime exposure to these cyanotoxins may affect public health, thus reliable detection, quantification, and enumeration of these harmful algae species has become a priority in water quality management. Traditional manual enumeration of algal bloom cells primarily involves microscopic identification which limited by inaccuracy and time-consumption. With the development of molecular techniques and an increasing number of microbial sequences available in the Genbank database, the use of molecular methods can be used for more rapid, reliable, and accurate detection and quantification. In this study, multiplex polymerase chain reaction （PCR） and real-time quantitative PCR （qPCR） techniques were developed and applied for monitoring cyanobacteria Microcystis spp. and C. raciborskii in the Macao Storage Reservoir （MSR）. The results showed that the techniques were successful for identifying and quantifying the species in pure cultures and mixed cultures, and proved to be a potential application for water sampling in MSR. When the target species were above 1 million cells/L, similar cell numbers estimated by microscopic enumeration and qPCR were obtained. Further quantification in water samples indicated that the ratio of the estimated number of cell by microscopy and qPCR was 0.4-12.9 for cyanobacteria and 0.2-3.9 for C. raciborskii. However, Microcystis spp. was not observed by manual enumeration, while it was detected at low levels by qPCR, suggesting that qPCR is more sensitive and accurate. Thus the molecular approaches provide an additional reliable monitoring option to traditional micro- scopic enumeration for the ecosystems monitoring program.

关键词： cyanobacteria Microcystis spp. C. racibors-kii microscopy PCR and real-time PCR