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Operations management for competitive advantage / Richard B. Chase, Nicholas J. Aquilano, F. Robert jacobs. 9th ed.

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国际女摄影师Lydia jacobs镜头下的油画风格摄影

丛书名： The Irwin/McGraw-Hill series. Operations and decision sciences.

2001年

作者： Richard B. Chase Nicholas J. Aquilano F. Robert jacobs.

来源：畅想之星图书光盘版（南... 畅想之星图书光盘版（南... 评论

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旅游世界 2020年第8期 68-87页

作者：朱国伟清荷不详大西洋摄影家协会

Lydia jacobs(清荷)美加籍华裔,多年任职婴幼儿产品工程师和平面设计师,擅长自然风光和静物摄影。自然风光作品曾获多伦多国际摄影节银奖,静物作品曾获多伦多国际兰花摄影比赛金奖。作品发表在***/member/lydiajacobs,【英国版】Practic... 详细信息

Lydia jacobs(清荷)美加籍华裔,多年任职婴幼儿产品工程师和平面设计师,擅长自然风光和静物摄影。自然风光作品曾获多伦多国际摄影节银奖,静物作品曾获多伦多国际兰花摄影比赛金奖。作品发表在***/member/lydiajacobs,【英国版】Practical Photography杂志,图虫和500px视觉中国等,曾任PPEA美国大众摄影交流协会西雅图分会会长和北美文学城摄影沙龙版主,现任大西洋摄影家协会副会长。

关键词：摄影家协会油画风格摄影比赛平面设计师静物摄影婴幼儿产品自然风光摄影节

Completeness of citizen science biodiversity data from a volunteered geographic information perspective

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Geo-Spatial Information Science 2017年第1期20卷 3-13页

作者： Clemens jacobs Alexander Zipf GIScience Research Group Institute of GeographyHeidelberg UniversityHeidelbergGermany

Observations of living organisms by citizen scientists that are reported to online portals are a valuable source of *** are also a special kind of volunteered geographic information(VGI).VGI data have issues of completeness,which arise from biases caused by the opportunistic nature of the data collection *** examined the completeness of bird species represented in citizen science observation data from eBird and iNaturalist in US National Parks(NPs).We used approaches for completeness estimation which were developed for data from OpenStreetMap,a crowdsourced map of the ***,we used an extrinsic approach,comparing species lists from citizen science data with National Park Service ***,we examined two intrinsic approaches using total observation numbers in NPs and the development of the number of new species being added to the data-set over *** from the extrinsic approach provided appropriate completeness estimations to evaluate the intrinsic *** found that total observation numbers are a good estimator of species completeness of citizen science data from US *** is also a close relationship between species completeness and the ratio of new species added to observation data *** numbers in a given year.

关键词： Citizen science Volunteered Geographic Information(VGI) data quality completeness

Between fighting and tolerance： reproductive biology of wingless males in the ant Cardiocondyla venustula

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Insect Science 2017年第5期24卷 818-828页

作者： Susanne jacobs Jurgen Heinze LS ZoologielEvolutionsbiologie Universitat Regensburg Regensburg Germany

Male reproductive tactics vary widely across the species of the ant genus Cardiocondyla, from obligatory lethal combat among co-occurring males to complete mutual tolerance. The African species C. venustula Wheeler, 1908 has an intermediate phylogenetic position between taxa with fighting males and taxa with tolerant males and also shows an intermediate male behavior. Males from 2 native populations in South Africa and a population introduced to Puerto Rico attacked and killed freshly eclosing rivals but rarely engaged in deadly fights with adult competitors, Instead, several males per colony established small ＂territories＂ in their natal nests and defended them against other males. Males with a stable territory had more contact with female sexuals than nonterritorial males and more frequently engaged in mating attempts. In controlled choice experiments, female sexuals did not show any preference for particular males. We suggest that male territoriality in C. venustula is an adaptation to the seasonal production of large numbers of female sexuals by multiple mothers.

关键词： Cardiocondyla ergatoid males Formicidae male competition sexual selection territoriality

Numerical prediction of the frictional losses in sliding bearings during start-stop operation

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Friction 2021年第3期9卷 583-597页

作者： Florian KÖNIG Christopher SOUS Georg jacobs Institute for Machine Elements and Systems Engineering Rheinisch-Westfälische Technische Hochschule Aachen UniversitySchinkelstraße 10Aachen 52062Germany

With the increased use of automotive engine start-stop systems,the numerical prediction and reduction of frictional losses in sliding bearings during starting and stopping procedures has become an important *** engineering practice,numerical simulations of sliding bearings in automotive engines are performed with statistical asperity contact models with empirical values for the necessary surface *** aim of this study is to elucidate the applicability of these approaches for the prediction of friction in sliding bearings subjected to start-stop *** this purpose,the friction performance of sliding bearings was investigated in experiments on a test rig and in transient mixed elasto-hydrodynamic simulations in a multi-body simulation environment(mixed-EHL/MBS).In mixed-EHL/MBS,the extended Reynold’s equation with flow factors according to Patir and Cheng has been combined on the one hand with the statistical asperity contact model according to Greenwood and Tripp and on the other hand with the deterministic asperity contact model according to *** detailed comparison of simulation and experimental results clarifies that the application of statistical asperity contact models with empirical values of the necessary inputs leads to large deviations between experiment and *** actual distribution and position of surface roughness,as used in deterministic contact modelling,is necessary for a reliable prediction of the frictional losses in sliding bearings during start-stop operation.

关键词： sliding bearing friction wearing-in contact model,mixed elasto-hydrodynamic simulation

Role of CD20^+ T cells in multiple sclerosis:implications for treatment with ocrelizumab

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Neural Regeneration Research 2020年第4期15卷 663-664页

作者： Stefan Gingele Thomas Skripuletz Roland jacobs Department of Neurology Hannover Medical SchoolHannoverGermany Department of Clinical Immunology&Rheumatology Hannover Medical SchoolHannoverGermany

Features of CD20^+T cells:CD20 is a membrane-spanning hosphoprotein strongly expressed on the cell surface of B lineage cells and is widely regarded as a B cell specific ***,CD20(Figure 1)is also expressed at a low level on a small subset of CD3^+T cells which therefore are sometimes referred to as CD20dimCD3^+T cells in contrast to CD20brightCD19^+B cells which represent the majority of cells expressing CD20(Hultin et al.,1993).The amount of the CD20 antigen has been assessed to be 25 to 50 times higher on CD20^+CD19^+B cells compared to CD20^+CD3^+T cells(Hultin et al.,1993).At first description of this cell population the frequency of these CD20^+T cells has been described to represent an average of 2.4%of all peripheral blood lymphocytes(50 healthy controls)(Hultin et al.,1993).

关键词： al. CD20 assessed

Void fill and support techniques to stabilize drift excavated through a transition zone mined by a TBM at the Stillwater mine

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International Journal of Mining Science and Technology 2017年第1期27卷 71-76页

作者： Johnson Josh jacobs Curt Ferster Mark Tadolini Stephen Stillwater Mining Company NyeMT 59061USA Minova GeorgetownKYUSA

Stillwater Mining Company is the only U.S. producer of platinum group metals （PGMs） and the largest producer outside of South Afiica and Russia. The company controls a considerable portion of the J-M reef and is currently developing the ＂Blitz Project,＂ which will provide a main haulage level, ore pass systems, backfill plants, and fiow-through ventilation to increase production and ensure sustainable extraction of this critical strategic mineral. While driving two sub-parallel footwall laterals 8125 m in length, one of the development drifts experienced a massive fall in a geologically disturbed area created by a mafic dike intrusion. Combinations of a void fill material （Tekseal）, polyurethane injection, fore poling coupled with steel arches, and supplemental bolting allow safe and efficient advance through this geologically dis- turbed zone. This paper presents the details of this project.

关键词： TBM Ground Dike Cutterhead

Influence of lanthanum level and interactions with nitrogen source on early development of Juglans nigra

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Journal of Rare Earths 2009年第2期27卷 270-279页

作者： Nicodemus Michael A Salifu K Francis jacobs Douglass F Department of Forestty and Natural Resources Hardwood Tree Improvement and Regeneration Center Purdue University West Lafayette IN 47907 USA

Rare earth elements have been used for 30 years in Chinese agriculture to improve growth and yield. Numerous scientific studies have shown improvements in physiology, mineral nutrition, and growth, though deleterious effects may also occur. Very few studies have been performed on woody species. We exponentially fertilized one-year old black walnut （Juglans nigra L.） seedlings with 0, 0.1, 1, 10, or 100 mg lanthanum （La） and 800 mg nitrogen （N） as NaNO3, （NH4）2SO4, NH4NO3, or no N. One month following final fertilization, growth, mineral nutrition, photosynthesis, chlorophyll, and nitrate reductase activity were assessed. Plants fertilized with the highest level of La had reduced fine root growth, concentrations of magnesium, calcium, nickel, and phosphorus, photosynthesis levels, and chlorophyll a content. Foliar La concentration showed an interaction effect, with three to four times greater concentration in plants fed at 100 mg La to those given 10 mg La for （NH4）2SO4 and NHaNO3 treatments. The results suggested no beneficial effects of La addition at levels used in this study and interactions between N source and La levels did not have an important impact on the growth, mineral nutrition, or physiology of black walnut seedlings.

关键词： lanthanum nitrate reductase chlorophyll photosynthesis Jugians nigra rare earths

The politics of the basic benefit package health reforms in Tajikistan

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Global Health Research and Policy 2019年第1期4卷 257-268页

作者： Eelco jacobs University of Basel BaselSwitzerland KIT Royal Tropical Institute AmsterdamThe Netherlands

Background:Health reform is a fundamentally political ***,evidence on the interplay between domestic politics,international aid and the technical dimensions of health systems,particularly in the former Soviet Union and Central Asia,remains *** regard has been given to the political dimensions of Tajikistan’s Basic Benefit Package(BBP)reforms that regulate entitlements to a guaranteed set of healthcare services while introducing *** objective of this paper is therefore to explore the governance constraints to the introduction and implementation of the BBP and associated health management ***:This qualitative study draws on literature review and key informant *** analysis was guided by a political economy framework exploring the interplay between structural and institutional features on the one hand and agency dynamics on the *** on that the article presents the main themes that emerged on structure-agency dynamics,forming the key governance constraints to the BBP reform and ***:Policy incoherence,parallel and competing central government mandates,and regulatory fragmentation,have emerged as dominant drivers of most other constraints to effective design and implementation of the BBP and associated health reforms in Tajikistan:overcharging and informal payments,a weak link between budgeting and policymaking,a practice of non-transparent budget bargaining instead of a rationalisation of health expenditure,little donor harmonisation,and weak accountability to ***:This study suggests that policy incoherence and regulatory fragmentation can be linked to the neopatrimonial character of the regime and donor behaviour,with detrimental consequences for the health system..These findings raise questions on the unintended effects of non-harmonised piloting of health reforms,and the interaction of health financing and management interventions with entrenched power ***

关键词： Health governance Health financing Health policy Health reform Tajikistan Political economy