检索结果-南通市图书馆

Efficiency of the motion amplification device with viscous dampers and its application in high-rise buildings

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2009年第4期8卷 521-536页

作者： henry c.Huang WSP Asia Ltd.

After nearly a decade of application and investigation, a motion amplification device with viscous dampers for energy dissipation has been recognized as an effective solution to mitigate wind or seismic excitation, especially for stiff structural systems. As a result of compensation of amplified motion, it has been proved that the efficiency of viscous damper largely depends on the motion amplification device configuration, particularly for device stiflhess. In this paper, a ＂scissor-jack＂ type of motion amplification device, called a ＂toggle brace damper＂ system, is studied. It is demonstrated that the efficiency of such a device reflected by its amplification factor is not merely a function of its geometric configuration, but is highly dependent on the support elements＇ stiffness as well, similar to the mechanism of a leverage arm. Accordingly, a mathematical model in terms of complex modulus of the viscous damper with consideration of the support brace＇s stiffness is established. The results indicate that the efficiency of the motion amplification device with viscous dampers significantly depends on the stiffness of the support elements. Other parameters, such as toggle brace configuration and damping values of the viscous damper, are studied and compared. As an application example, numerical analyses are conducted to study the dynamic performance of a 39-story office tower installed with toggle brace dampers constructed on soft soil in a reclaimed area, under a combined effect of the vortex shedding of an adjacent existing 52-story building and earthquakes. The results show that viscous dampers with a motion amplification system using a properly designed toggle brace device proved to be an effective solution to alleviate the external excitations.

关键词： motion amplification device vibration mitigation viscous damper energy dissipation toggle brace damper

A stable cS-FEM for the static and seismic stability of a single square tunnel in the soil where the shear strength increases linearly with depth

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2022年第4期14卷 1253-1265页

作者： H.c.nguyen L.nguyen-Son Department of civil and Environmental Engineering Imperial College LondonLondonUK Department of civil Engineering and Industrial Design University of LiverpoolLiverpoolUK Faculty of civil Engineering Ho Chi Minh City University of Technology(HUTECH)Ho Chi Minh CityViet Nam

A numerical procedure using a stable cell-based smoothed finite element method(cS-FEM)is presented for estimation of stability of a square tunnel in the soil where the shear strength increases linearly with *** kinematically admissible displacement fields are approximated by uniform quadrilateral elements in conjunction with the strain smoothing technique,eliminating volumetric locking issues and the singularity associated with the Mohrecoulomb ***,a rich set of simulations was performed to compute the static stability of a square tunnel with different geometries and soil *** presented results are in excellent agreement with the upper and lower bound solutions using the standard finite element method(FEM).The stability charts and tables are given for practical use in the tunnel design,along with a newly proposed formulation for predicting the undrained stability of a single square ***,the seismic stability number was computed using the present numerical *** results reveal that the seismic stability number reduces with an increasing value of the horizontal seismic acceleration(a_(h)),for both cases of the weightless soil and the soil with unit ***,the link between the static and seismic stability numbers is described using corrective factors that represent reductions in the tunnel stability due to seismic *** is shown from the numerical results that the corrective factor becomes larger as the unit weight of soil mass increases;however,the degree of the reduction in seismic stability number tends to reduce for the case of the homogeneous ***,this advanced numerical procedure is straightforward to extend to three-dimensional(3D)limit analysis and is readily applicable for the calculation of the stability of tunnels in highly anisotropic and heterogeneous soils which are often encountered in practice.

关键词： Tunnels Stability Limit analysis cell-based smoothed finite element method (cS-FEM) Second-order cone programming(SOcP)

Pointed p^3-Dimensional Hopf Algebras in Positive characteristic

在线全文

学校读者我要写书评

暂无评论

Algebra colloquium 2018年第3期25卷 399-436页

作者： Van c. nguyen Xingting Wang Department of Mathematics Hood College Frederick MD 21701 USA Department of Mathematics Howard University Washington DC 20059 USA

We focus on the classification of pointed p^3-dimensional Hopf algebras H over any algebraically closed field of prime characteristic p 〉 0. In particular, we consider certain cases when the group of grouplike elements is of order p or p^2 that is, when H is pointed but is not connected nor a group algebra. The structures of the associated graded algebra gr H are completely described as bosonizations of graded braided Hopf algebras over group algebras, and most of the lifting structures of H are given. This work provides many new examples of （parametrized） non-commutative, non-cocommutative finite- dimensional Hopf algebras in positive characteristic.

关键词： braided Hopfalgebras Yetter-Drinfeld modules positive characteristic pointed Hopf algebras Nichols algebras

The use of the node-based smoothed finite element method to estimate static and seismic bearing capacities of shallow strip footings

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 180-196页

作者： H.c.nguyen T.Vo-Minh Department of civil and environmental engineering imperial college londonuk Department of civil engineering and industrial design university of liverpoolliverpooluk Faculty of civil engineering ho chi minh city university of technology(hutech)ho chi minh cityviet nam

The node-based smoothed finite element method(NS-FEM)is shortly presented for calculations of the static and seismic bearing capacities of shallow strip footings.A series of computations has been performed to assess variations in seismic bearing capacity factors with both horizontal and vertical seismic *** results obtained agree very well with those using the slip-line method,revealing that the magnitude of the seismic bearing capacity is highly dependent upon the combinations of various directions of both components of the seismic *** upward vertical seismic acceleration reduces the seismic bearing capacity compared to the downward vertical seismic acceleration in *** addition,particular emphasis is placed on a separate estimation of the effects of soil and superstructure inertia on each seismic bearing capacity *** the effect of inertia forces arising in the soil on the seismic bearing capacity is non-trivial,and the superstructure inertia is the major contributor to reductions in the seismic bearing *** tables and charts are given for practical application to the seismic design of the foundations.

关键词： Limit analysis Node-based smoothed finite element method(NS-FEM) Second-order cone programming(SOcP) Seismic bearing capacity Strip footing

Interventions and targets aimed at improving quality in inflammatory bowel disease ambulatory care

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2013年第38期19卷 6375-6382页

作者： Adam V Weizman Geoffrey c nguyen Division of Gastroenterology Women’s College HospitalUniversity of TorontoTorontoON M5S 1B2Canada Mount Sinai Hospital centre for Inflammatory Bowel Disease University of TorontoTorontoON M5G 1X5Canada Division of Gastroenterology and Hepatology Johns Hopkins School of MedicineBaltimoreMD 21205United States

Over the past decade,there has been increasing focus on improving the quality of healthcare delivered to patients with chronic diseases,including inflammatory bowel *** bowel disease is a complex,chronic condition with associated morbidity,health care costs,and reductions in quality of *** condition is managed primarily in the outpatient *** delivery of high quality of care is suboptimal in several ambulatory inflammatory bowel disease domains including objective assessments of disease activity,the use of steroid-sparing agents,screening prior to anti-tumor necrosis factor therapy,and monitoring thiopurine *** review outlines these gaps in performance and provides potential initiatives aimed at improvement including reimbursement programs,quality improvement frameworks,collaborative efforts in quality improvement,and the use of healthcare information technology.

关键词： Ambulatory care crohn’s disease Inflammatory bowel disease Quality improvement Ulcerative colitis

A correlation between pulse diagnosis of human body and health monitoring of structures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2004年第1期3卷 117-125页

作者： c.c.chang henry T.Y.Yang Department of civil Engineering Hong Kong University of Science and TechnologyHong Kong Department of Mechanical and Environmental EngineeringUniversity of California Department of Mechanical and Environmental Engineering University of California

The concept of health monitoring is a key aspect of the field of medicine that has been practiced for a long time. A commonly used diagnostic and health monitoring practice is pulse diagnosis, which can be traced back approximately five thousand years in the recorded history of china. With advances in the development of modern technology, the concept of health monitoring of a variety of engineering structures in several applications has begun to attract widespread attention. Of particular interest in this study is the health monitoring of civil structures. It seem natural, and even beneficial, that these two health-monitoring methods, one as applies to the human body and the other to civil structures, should be analyzed and compared. In this paper, the basic concepts and theories of the two monitoring methods are first discussed. Similarities are then summarized and commented upon. It is hoped that this correlation analysis may help provide structural engineers with some insights into the intrinsic concept of using pulse diagnosis in human health monitoring, which may of be some benefit in the development of modern structural health monitoring methods.

关键词： human health monitoring pulse diagnosis structural health monitoring vibration-based techniques local detection techniques

Presence of phthalates in gastrointestinal medications: Is there a hidden danger?

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2013年第41期19卷 7042-7047页

作者： Zane R Gallinger Geoffrey c nguyen Mount Sinai Hospital centre for Inflammatory Bowel Disease University of TorontoTorontoOntarioM5G 1X5Canada Division of Gastroenterology Johns Hopkins University School of MedicineBaltimoreMD 21287United States

Pharmaceutical companies that produce gastrointestinal(GI)medications often utilize phthalates for their ability to localize medication *** prescribed GI medications that may utilize phthalates are 5-Aminosalicylates,proton pump inhibitors,and pancreatic *** understanding of the cumulative health effects of phthalates from medications remains unclear,and there is increasing evidence that phthalates are not *** studies in animals have shown that phthalates,specifically dibutyl phthalate and Di-(2-ethyl-hexyl)phthalate,have the potential to alter and/or inhibit reproductive biology and in utero *** the lack of definitive human data,many cohort and cross-sectional studies demonstrate concerning associations between phthalates and poor health status,specifically developmental *** studies and studies with larger sample sizes are required to determine whether phthalates actually cause negative health *** is also important that physicians regularly review and discuss with patients the medicinal ingredients in their medications and supplements,specifically in pregnant woman with inflammatory bowel disease.

关键词： Phthalates Dibutyl phthalate 5-Aminosalicylates Medications Development Pregnancy

Use of Silicon Substituents in the Syntheses of Natural and Non-natural Molecules

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 chemistry 2005年第8期23卷 1106-1108页

作者： WONG, henry N. c. Department of chemistry Institute of Chinese Medicine and Central Laboratory of Institute of Molecular Technology for Drug Discovery and Synthesis The Chinese University of Hong Kong Shatin New TerritoriesHong Kong SAR China

Trimethylsilyl groups have been used in our research as a director as well as a bulky and lipophilic group in our quest for natural and non-natural molecules.

关键词： trimethylsilyl bulky group lipophilic group

Quality of care delivered to hospitalized inflammatory bowel disease patients

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2013年第38期19卷 6360-6366页

作者： Adam V Weizman Geoffrey c nguyen Division of Gastroenterology Women’s College HospitalUniversity of TorontoTorontoM5S 1B2OntarioCanada Mount Sinai Hospital centre for Inflammatory Bowel Disease University of TorontoTorontoM5G 1X5OntarioCanada Division of Gastroenterology and Hepatology Johns Hopkins School of MedicineBaltimoreMD 21201United States

Hospitalized patients with inflammatory bowel disease(IBD)are at high risk for morbidity,mortality,and health care utilization *** the literature on trends in hospitalization rates for this disease is conflicting,there does appear to be significant variation in the delivery of care to this complex group,which may be a marker of suboptimal quality of *** is a need for improvement in identifying patients at risk for hospitalization in an effort to reduce ***,appropriate screening for a number of hospital acquired complications such as venous thromboembolism and clostridium difficile infection is *** review discusses areas of inpatient care for IBD patients that are in need of improvement and outlines a number of potential quality improvement initiatives such as payfor-performance models,quality improvement frameworks,and healthcare information technology.

关键词： crohn’s disease Hospitalization Inflammatory bowel disease Quality improvement Ulcerative colitis