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Finite element analysis on the static and fatigue characteristics of composite multi-leaf spring

2008年

作者： jeffrey s. Abrams Robert H. Bell

来源：畅想之星图书光盘版（南... 评论

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2012年第3期13卷 159-164页

作者： Joo-teck jeffrey KUEH Tarlochan FARIs Department of Mechanical Engineering Universiti Tenaga Nasional

This paper investigated the static and fatigue behaviors of steel and composite multi-leaf spring using the ANsYs V I 2 software. The dimensions of an existing conventional leaf spring of a light commercial vehicle were used. The same dimensions were used to design composite multi-leaf spring for the two materials, E-glass fiber/epoxy and E-glass fiber/vinyl ester, which are of great interest to the transportation industry. Main consideration was given to the effects of material composition and its fiber orientation on the static and fatigue behaviors of leaf spring. The design constraints were bending stresses, deflection and fatigue life. Compared to the steel leaf spring, the designed composite spring has much lower bending stresses and deflections and higher fatigue life cycles.

关键词： Leaf spring Composites Finite element stress Deflection Fatigue

Ranking grey numbers based on dominance grey degrees

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Journal of systems Engineering and Electronics 2014年第4期25卷 618-626页

作者： Yong Liu jeffrey Forrest Naiming Xie College of Economics and Management Nanjing University of Aeronautics and Astronautics school of Business Jiangnan University Mathematics Department Slippery Rock University of USA

With respect to the decision making problems where a lot of fuzzy and grey information always exists in the real-life decision making information system methods as fuzzy mathematics, it is difficult for such uncertainty probability, and interval numbers to deal with. To this end, based on the thought and method of grey numbers, grey degrees and interval numbers, the concept of dominance grey degree is defined. And then a method of ranking interval grey numbers based on the dominance grey degree is proposed. After discussing the relevant properties, the paper finally uses an example to demonstrate the effectiveness and applicability of the model. The result shows that the proposed model can more accurately describe uncertainty decision making problems, and realize the total ordering process for multiple-attribute decision-making problems.

关键词： grey information dominance grey degree intervalgrey number total ordering.

Bioinspired Dry Adhesive Materials and Their Application in Robotics： A Review

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Journal of Bionic Engineering 2016年第2期13卷 181-199页

作者： Yasong Li jeffrey Krahn Carlo Menon MENRVA Research Group School of Engineering Science Simon Fraser University 8888 University Drive Burnaby BC V5A 1S6 Canada

Dry adhesives inspired from climbing animals, such as geckos and spiders, rely on van der Waals forces to attach to the opposing surface. Biological fibrillar dry adhesives have a hierarchical structure closely resembling a tree： the surface of the skin on the animal＇s feet is covered in arrays of slender micro-fibrils, each of which supports arrays of fibrils in submicron dimensions. These nano-meter size fibrils can conform closely to the opposing surfaces to induce van der Waals interaction. Bioinspired dry adhesives have been developed in research laboratories for more than a decade. To mimic the biological fibrillar adhesives, fibrillar structures have been prepared using a variety of materials and geometrical arrangements. In this review article, the mechanism and selected fabrication methods of fibrillar adhesives are summarized for future reference in adhesive development. Robotic applications of these bioinspired adhesives are also introduced in this article. Various successful appli- cations of bioinspired fibrillar adhesives can shed light on developing smart adhesives for use in automation.

关键词： bioinspired gecko adhesive van der Waals forces biomimetic climbing robot bioinspired tape

Fabrication and Testing of self Cleaning Dry Adhesives Utilizing Hydrophobicity Gradient

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Journal of Bionic Engineering 2015年第2期12卷 270-275页

作者： Enrico Bovcro jeffrey Krahn Carlo Menon MENRVA Lab School of Engineering Science Simon Fraser University 8888 University Drive Burnaby BC Canada V5A 1S6

In this paper we present a method to create a hydrophobicity gradient on the surface of a Polydimethylsiloxane （PDMs） dry adhesive. The method consists of the partial silanization of the surface of the dry adhesive by Chemical Vapour Deposition （CVD） of octadecyltrichlorosilane （OTs）. The partial silanization of the surface of the sample results in a hydrophobic to hy- drophilic gradient across the surface of the dry adhesive. The resulting change in hydrophobicity across the surface of the dry adhesive results in the uphill motion of a droplet of water, which appears to be directly proportional to the area of contact between the droplet and the adhesive. Normal adhesion testing is performed to quantify the effect of the hydrophobic gradient across the surface of the sample. While a variation in adhesion are only minimally affected by the silanization, and the motion strength across the sample is measured, the adhesive properties of the droplet of water doesn＇t cause any loss of adhesion.

关键词： dry adhesion self cleaning hydrophobic silanization polymers PDMs

A zoological perspective on payments for ecosystem services

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Integrative Zoology 2007年第2期2卷 68-78页

作者： jeffrey A.McNEELY IUCN–The World Conservation Union GlandSwitzerland

The concept of payments for ecosystem services is being developed as an important means of providing a more diverse flow of benefits to people living in and around habitats valuable for *** Kyoto Protocol,under the United Nations Framework Convention on Climate Change,includes a Clean Development Mechanism to provide for payments for certain forms of carbon sequestration that may benefit animal species(at least as an incidental benefit).Other market-based approaches for paying for carbon sequestration services outside the Kyoto framework are being promoted in various parts of the *** common form of payment for ecosystem services is compensating upstream landowners for managing their land in ways that maintain downstream water quality;this can include habitat management that benefits wild animal *** biodiversity itself is difficult to value,it can be linked to other markets,such as certification in the case of sustainably-produced forest *** paper expands on some of the markets for ecosystem services that also benefit wildlife,identifies relevant sources of information,and highlights some of the initiatives linking such markets to poverty *** markets work for ecosystem services requires an appropriate policy framework,government support,operational institutional support,and innovation at scales from the site level to the national *** have much to contribute to all of these steps.

关键词： biodiversity carbon trading ecosystem services payments watersheds

Using economic instruments to overcome obstacles to in situ conservation of biodiversity

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Integrative Zoology 2006年第1期1卷 25-31页

作者： jeffrey A.McNEELY IUCN-The World Conservation Union GlandSwitzerland

The leading direct cause of the loss of biodiversity is habitat alteration and *** we are to address this cause directly,we need to find ways of changing the behavior of rural *** has shown that this is done most effectively through the use of economic instruments,ranging from taxes that discourage over-exploitation,to direct payments for conservation activities carried out by rural land-owners or those occupying the *** many parts of the world,governments provide incentives such as tax breaks to private *** countries recognize specific use rights on particular parts of the land,enabling the land-owners to earn appropriate *** many protected areas have resident human populations,it is especially important that they be encouraged to contribute to the objectives of the protected area,and economic incentives offer an important way of doing so;they might,for example,be given employment in the protected area or in associated tourism *** payments to farmers for conserving watersheds is becoming increasingly popular,in both developed and developing *** conservation will require both removing perverse subsidies and developing a wide range of approaches for rewarding land-owners for biodiversity conservation activities.

关键词： ecosystem services incentives indigenous peoples protected areas resource rights

systems or species? Approaches to conservation for the 21st century

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Integrative Zoology 2006年第2期1卷 86-95页

作者： jeffrey A.McNEELY IUCN-The World Conservation Union GlandSwitzerland

One of the hot debates in the conservation community is whether to focus on individual species(for example,through species recovery plans,or lists of threatened species)or on systems approaches(such as the ecosystem approach advocated by the Convention on Biological Diversity).This paper will discuss some of the various options,before reaching a conclusion that both approaches are valid and mutually reinforcing,and that the dichotomy is a false *** more importantly,no conservation investment is likely to be effective if economic,social,and political factors are driving in the opposite ***,we need multiple approaches that build a stronger political constituency,new ways of providing knowledge for decisions,better ways of mobilizing information and dynamic approaches that enable us to adapt to changing conditions,and new ways to generate funding for conservation.

关键词： biodiversity conservation ecosystem approach protected areas species

Future technology-enabled care for diabetes and hyperglycemia in the hospital setting

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World Journal of Diabetes 2019年第9期10卷 473-480页

作者： Alex Renato Montero jeffrey s Dubin Paul sack Michelle F Magee Medstar Diabetes Institute WashingtonDC 20010United States Department of Medicine MedStar Georgetown University HospitalWashingtonDC 20007United States Medstar Washington Hospital Center WashingtonDC 20010United States Medstar Union Memorial Hospital BaltimoreMD 21218United States Medstar Health Research Institute WashingtonDC 20010United States

Patients with diabetes are increasingly common in hospital settings where optimal glycemic control remains *** technology-enabled support systems are being designed,adapted and evaluated to meet this *** pump use,increasingly common in outpatients,has been shown to be safe among select *** pump protocols and provider training are needed to optimize pump use in the *** glucose monitoring(CGM)has been shown to be comparable to usual care for blood glucose surveillance in intensive care unit(ICU)settings but data on cost effectiveness is *** use in non-ICU settings remains investigational and patient use of home CGM in inpatient settings is not recommended due to safety *** to unstructured insulin prescription,a continuum of effective electronic medical record-based support for insulin prescription exists from passive order sets to clinical decision support to fully automated electronic Glycemic Management *** efficacy and cost among these systems remains *** array of novel platforms are being evaluated to engage patients in technology-enabled diabetes education in the *** hold tremendous promise in affording universal access to hospitalized patients with diabetes to effective self-management education and its attendant short/long term clinical benefits.

关键词： Diabetes Inpatients Continuous subcutaneous insulin infusion Continuous glucose monitoring Clinical decision support Patient education self-management

Abnormal psychology in a changing world / 5th ed.

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Abnormal psychology in a changing world /