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斯里兰卡破坏珊瑚礁的环境经济状况

人类环境杂志 1998年第8期27卷 625-632页

作者： h■kan berg Marcus C.hman Sebastian Tro■ng 0lofLindén 王燕海洋生态毒理学瑞典斯德哥尔摩大学动物学系哥斯达黎加Tortnguero加勒比保护公司斯德哥尔摩大学动物学系

珊瑚礁对于很多人,特别是发展中国家沿海地区的人口来说是一种非常重要的资源。有关斯里兰卡和东南亚珊瑚礁的有效信息已被用来评价珊瑚礁所提供的生态作用和从一些生态系统功能中所得到的长期的经济效益。据估计,斯里兰卡珊瑚礁的经济... 详细信息

珊瑚礁对于很多人,特别是发展中国家沿海地区的人口来说是一种非常重要的资源。有关斯里兰卡和东南亚珊瑚礁的有效信息已被用来评价珊瑚礁所提供的生态作用和从一些生态系统功能中所得到的长期的经济效益。据估计,斯里兰卡珊瑚礁的经济价值为20年时间里每平方公里礁的价值为14万～7500万美元。在调查了开采珊瑚的经济后果并分析了经营20多年的旅游区后发现,其经济成本(11万～736万美元)超过净收益(75万～167万美元)661万美元之多。最大成本和旅游业(200万～300万美元)的衰落和侵蚀(100万～400万美元)的增加有关。然而,由于从短期的角度来看,从开采珊瑚中得到的利益比从捕鱼和农业中得到的还多,所以在农村,仍然有开采珊瑚的刺激。这些结果对于管理会产生一定的影响并且还表明,通过立法来禁止沿海地区开采珊瑚礁的行为,对国家的经济发展有好处。

关键词：珊瑚礁环境经济斯里兰卡经济价值

A CALCULUS FOR SERVICES INNOVATION

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Journal of Systems Science and Systems Engineering 2007年第2期16卷 129-165页

作者： James M. TIEN Daniel berg Department of Decision Sciences and Engineering Systems Rensselaer Polytechnic Institute Troy New York USA

Innovation in the services area - especially in the electronic services （e-services） domain - can be systematically developed by first considering the strategic drivers and foci, then the tactical principles and enablers, and finally the operational decision attributes, all of which constitute a process or calculus of services innovation. More specifically, there are four customer drivers （i.e., collaboration, customization, integration and adaptation）, three business foci （i.e., creation-focused, solution-focused and competition-focused）, six business principles （i.e., reconstruct market boundaries, focus on the big picture not numbers, reach beyond existing demand, get strategic sequence right, overcome organizational hurdles and build execution into strategy）, eight technical enablers （i.e., software algorithms, automation, telecommunication, collaboration, standardization, customization, organization, and globalization）, and six attributes of decision informatics （i.e., decision-driven, information-based, real-time, continuously-adaptive, customer-centric and computationally-intensive）. It should be noted that the four customer drivers are all directed at empowering the individual - that is, at recognizing that the individual can, respectively, contribute in a collaborative situation, receive customized or personalized attention, access an integrated system or process, and obtain adaptive real-time or just-in-time input. The developed process or calculus serves to identify the potential white spaces or blue oceans for innovation. In addition to expanding on current innovations in services and related experiences, white spaces are identified for possible future innovations; they include those that can mitigate the unforeseen consequences or abuses of earlier innovations, safeguard our rights to privacy, protect us from the always-on, interconnected world, provide us with an authoritative search engine, and generate a GDP metric that can adequately measure the gro

关键词： Services innovation decision informatics software algorithms automation globalization collaboration customization integration adaptation standardization telecommunication organization business principles

Small-Scale Mineralogical heterogeneity from Variations in Phase Assemblages in the Transition Zone and D" Layer Predicted by Convection Modelling

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Journal of Earth Science 2011年第2期22卷 160-168页

作者： Arie P van den berg David A Yuen Michael h G Jacobs Maarten V de hoop Earth Sciences Department Utrecht University Department of Geology and Geophysics and Minnesota Supercomputing Institute University of MinnesotaMinneapolisMN 55415USA Institut für Metallurgie TU ClausthalClausthal-ZellerfeldGermany Department of Mathematics and Center of Applied and Computational Mathematics Purdue UniversityWest LafayetteINUSA

Small-scale heterogeneity in the deep mantle is concentrated in the upper-mantle transition zone （TZ）, in the depth range 410-660 km and also at the bottom 250 km D＂ region. This encourages a more detailed investigation of the potential for seismic reflectivity imaging by modelling heterogeneous structures in mantle convection models including phase transitions of the TZ and D＂ regions. We applied finite elements with variable spacing near the boundary layers in 2-D cylindrical geometry that allow for sufficient spatial resolution. We investigated several models including an extended Boussinesq （EBA） model, focused on the D＂ region, and a compressible （ALA） model for the TZ region. The results for the D＂ region show typical lens-shaped structures of post-perovskite （PPV） embedded in the perovskite （PV） background mantle, where the thickness of the lenses, at 200-400 km, strongly depends on the Clapeyron slope of the PV-PPV transition. A second phase transition （double crossing） occurs in case the core temperature is higher than the intercept temperature Ti. Our phase-dependent rheology results in contrasting effective viscosity between PV and PPV. Our model results reveal a distinctly clear mechanical weakening of the PPV lenses with about an order of magnitude lower viscosity. The shear wave-speed distributions computed from our convection results are strongly correlated with the heterogeneous distribution of the mineral phase. Gradients in the seismic wave-speed that are the target of seismological reflectivity imaging are clearly revealed. The wave-speed results show a clear resolution of the top and bottom interfaces of the PPV lenses. Our ALA model for the TZ is based on a thermodynamical model for the magnesium end- member of an olivine-pyroxene mantle. The model predicts a much more complex distribution of mineral phases, compared to our D＂ results, in agreement with the greater number of mineral phases involved in the olivine-pyroxene phase diagram for the P

关键词： mantle convection phase transition post-perovskite mineralogical heterogeneity.

ON SERVICES RESEARCh AND EDUCATION

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Journal of Systems Science and Systems Engineering 2006年第3期15卷 257-283页

作者： James M.TIEN Daniel berg Department of Decision Sciences and Engineering Systems Rensselaer Polytechnic Institute

The importance of the services sector can not be overstated; it employs 82.1 percent of the U. S. workforce and 69 percent of graduates from an example technological university. Yet, university research and education have not followed suit. Clearly, services research and education deserve our critical attention and support since services - and services innovation - serve as an indispensable engine for global economic growth. The theme of this paper is that we can and should build services research and education on what has occurred in manufacturing research （especially in regard to customization and intellectual property） and education; indeed, services and manufactured goods become indistinguishable as they are jointly co-produced in real-time. Fortunately, inasmuch as manufacturing concepts, methodologies and technologies have been developed and refined over a long period of time （i.e., since the 1800s）, the complementary set of concepts, methodologies and technologies for services are more obvious. however, while new technologies （e.g., the Internet） and globalization trends have served to enable, if not facilitate, services innovation, the same technologies （e.g., the Internet） and 21st Century realities （e.g., terrorism） are making services innovation a far more complex problem and, in fact, may be undermining previous innovations in both services and manufacturing. Finally, there is a need to define a ＂knowledge-adjusted＂ GDP metric that can more adequately measure the growing knowledge economy, one driven by intangible ideas and services innovation.

关键词： Services manufacturing customization innovation education intellectual property

Preparation of AlN thin films for film bulk acoustic resonator application by radio frequency sputtering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 464-470页

作者： kan LI hao JIN De-miao WANG Yi-fei TANG Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

Aluminum nitride （AlN） thin films with high c-axis orientation have been prepared on a glass substrate with an Al bottom electrode by radio frequency （RF） reactive magnetron sputtering. Based on the analysis of berg＇s hysteresis model, the improved sputtering system is realized without a hysteresis effect. A new control method for rapidly depositing highly c-axis oriented AlN thin films is proposed. The N2 concentration could be controlled by observing the changes in cathode voltage, to realize the optimum processing condition where the target could be fixed stably in the transition region, and both stoichiometric film composition and a high deposition rate could be obtained. Under a 500 W RF power of a target with a 6 cm diameter, a substrate temperature of 450 ℃, a target-substrate distance of 60 mm and a N2 concentration of 25%, AlN thin film with preferential （002） orientation was deposited at 2.3 μm/h which is a much higher rate than previously achieved. Through X-ray diffraction （XRD） analysis, the full width at half maximum （FWhM） of AlN （002） was shown to be about 0.28°, which shows the good crystallinity and crystal orientation of AlN thin film. With other parameters held constant, any increase or decrease in N2 concentration results in an increase in the FWhM of AlN.

关键词： Aluminum nitride (A1N) Piezoelectric thin film Radio frequency (RF) reactive sputtering Preferred orientation,Film bulk acoustic resonator (FBAR)

Unsupervised learning of charge-discharge cycles from various lithium-ion battery cells to visualize dataset characteristics and to interpret model performance

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Energy and AI 2024年第3期17卷 397-405页

作者： Akihiro Yamashita Sascha berg Egbert Figgemeier helmholtz Institute Münster:Ionics in Energy Storage(IMD-4/hI MS) Forschungszentrum JülichJülichGermany Institute for Power Electronics and Electrical Drives(ISEA) RWTH Aachen UniversityAachenGermany Jülich Aachen Research Alliance JARA-EnergyGermany

Machine learning (ML) is a rapidly growing tool even in the lithium-ion battery (LIB) research field. To utilize this tool, more and more datasets have been published. however, applicability of a ML model to different information sources or various LIB cell types has not been well studied. In this paper, an unsupervised learning model called variational autoencoder (VAE) is evaluated with three datasets of charge-discharge cycles with different conditions. The model was first trained with a publicly available dataset of commercial cylindrical cells, and then evaluated with our private datasets of commercial pouch and hand-made coin cells. These cells used different chemistry and were tested with different cycle testers under different purposes, which induces various characteristics to each dataset. We report that researchers can recognise these characteristics with VAE to plan a proper data preprocessing. We also discuss about interpretability of a ML model.

关键词： Unsupervised learning Dimensionality reduction Inductive bias .Machine learning Variational autoencoder

A CASE FOR SERVICE SYSTEMS ENGINEERING

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Systems Science and Systems Engineering 2003年第1期12卷 13-38页

作者： James M.TIEN Daniel berg Department of Decision Sciences and Engineering Systems Rensselaer Polytechnic Institute Troy New York 12110-3590U.S.A.Department of Decision Sciences and Engineering Systems Rensselaer Polytechnic Institute TroyNew York 12110-3590U.S.A.

A case is made for further developing a branch of systems engineering that focuses on problems and issues which arise in the service sector. We promulgate this special focus not only because of the size and importance of the service sector but also because of the unique opportunities that systems engineering can exploit in the design and joint production and delivery of services. We begin by considering the economic, technological and demographic contexts within which the service sector has flourished; we then address both services, especially emerging services, and systems engineering, followed by a discussion of how to advance the field of service systems engineering, and concluding with several remarks. In particular, a number of service systems engineering methods are identified to enhance the design and production/delivery of services, especially taking advantage of the unique features that characterize services - namely, services, especially emerging services, are information-driven, customer-centric, e-oriented, and productivity-focused.

关键词： Service sector systems engineering information technology decision technologies customer-centric productivity

Ab initio prediction of fast non-equilibrium transport of nascent polarons in SrI2: a key to high-performance scintillation

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npj Computational Materials 2016年第1期2卷 77-83页

作者： Fei Zhou Babak Sadigh Paul Erhart Daniel Åberg Physical and Life Sciences Directorate Lawrence Livermore National LaboratoryLivermoreCAUSA Department of Physics Chalmers University of TechnologyGothenburgSweden

The excellent light yield proportionality of europium-doped strontium iodide(SrI2:Eu)has resulted in state-of-the-artγ-ray detectors with remarkably high-energy resolution,far exceeding that of most halide *** this class of materials,the formation of self-trapped hole polarons is very ***,polaron formation is usually expected to limit carrier mobilities and has been associated with poor scintillator light-yield proportionality and *** using a recently developed first-principles method,we perform an unprecedented study of polaron transport in SrI2,both for equilibrium polarons,as well as nascent polarons immediately following a self-trapping *** propose a rationale for the unexpected high-energy resolution of *** identify nine stable hole polaron configurations,which consist of dimerised iodine pairs with polaron-binding energies of up to 0.5 *** are connected by a complex potential energy landscape that comprises 66 unique nearest-neighbour migration *** initio molecular dynamics simulations reveal that a large fraction of polarons is born into configurations that migrate practically barrier free at room ***,carriers created duringγ-irradiation can quickly diffuse away reducing the chance for nonlinear recombination,the primary culprit for non-proportionality and resolution *** conclude that the flat,albeit complex,landscape for polaron migration in SrI2 is a key for understanding its outstanding *** insight provides important guidance not only for the future development of high-performance scintillators but also of other materials,for which large polaron mobilities are crucial such as batteries and solid-state ionic conductors.

关键词： polaron equilibrium iodine

hip prosthetic loosening:A very personal review

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World Journal of Orthopedics 2021年第9期12卷 629-639页

作者： Bengt Mjöberg Department of Orthopedics Lund UniversityLund SE-22100Sweden

hip prosthetic loosening is often difficult to detect at an early stage,and there has been uncertainty for a long time as to when the loosening occurs and thus to the basic *** comparing different diagnostic methods,we found that loosening is best defined as prosthetic migration and measured by radiostereometric *** evidence indicates that poor interlock,poor bone quality,and resorption of a necrotic bone bed may initiate loosening during or shortly after surgery;this forms the basis of the theory of early *** factors do affect the subsequent progression of loosening,which may increase subclinically during a long period of ***,the loosening may be detected on standard radiographs and may be interpreted as late loosening but should to be interpreted as late detection of *** theory of early loosening explains the rapid early migration,the development of periprosthetic osteolysis and granulomas,the causality between wear and loosening,and largely the epidemiology of clinical failure of hip *** discussed are definition of loosening,the pattern of early migration,the choice of migration threshold,the current understanding of loosening,a less exothermic bone cement,cemented taper-slip stems,a new exciting computed tomography-based technique for simpler implant migration studies,and research suggestions.

关键词： hip prosthesis Prosthesis failure Radiostereometric analysis Bone resorption Bone cements Radionuclide imaging