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What's So Special about China's Producer Services?An Input–output Analysis 被引量:5
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作者 Dazhong Cheng Peter w.daniels 《China & World Economy》 SCIE 2014年第1期103-120,共18页
In the present study, five stylized facts about China "s producer services are established through international, intersectoral and intertemporal comparisons based on input --output tables. First, the overall service... In the present study, five stylized facts about China "s producer services are established through international, intersectoral and intertemporal comparisons based on input --output tables. First, the overall service input ratio is the lowest in all the sample economies. Second, most producer services are supplied by the traditional labor-intensive sectors. Third, manufacturing is the biggest user of producer services, and service industry is the second, while the opposite is true for most of the other sample economies. Fourth, unlike other economies, China "s "R&D" is characterized more by consumer services than producer services. Fifth, China has fairly lower service input ratios in almost all the industries. The backward and forward linkages coefficients are both smaller for "real estate activities" and "finance and insurance. "" Policy reform should focus not only on specific producer services but also on reducing obstacles that are inhibiting the balanced development of diverse producer services that will help China to optimize its economic structure. 展开更多
关键词 Chinese economy input-output analysis producer services
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Frequency related localisation of harmonic elastic waves in stratified welds
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作者 D.J.Colquitt A.B.Movchan +1 位作者 I.S.Jones w.daniels 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第4期567-572,共6页
The paper presents a computational model for elastic waves in a structured weld adjacent to the free surface of an elastic solid. The main emphasis is on the interaction of waves with the micro-structure of the weld. ... The paper presents a computational model for elastic waves in a structured weld adjacent to the free surface of an elastic solid. The main emphasis is on the interaction of waves with the micro-structure of the weld. Effects of localisation and channeling of waves are addressed. A model of a grain structure within the weld is also considered. 展开更多
关键词 Macro-structured welds Waves in stratified media Dispersion Localisation
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服务地理学的前景
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作者 P.w.daniels 王庆生 +1 位作者 杨延哲 浦光梁 《地理译报》 CSCD 1992年第4期15-19,共5页
一、需要继续向劳务生产转移吗?发达的经济结构仍需完成从商品生产到服务生产的转移过程。截至1990年1月,美国制造业(包括建筑业)的就业水平比1980年降低了3%,(100万人),而服务业的就业率却增加了3%,(2000万人)。从制造业向服务业转移... 一、需要继续向劳务生产转移吗?发达的经济结构仍需完成从商品生产到服务生产的转移过程。截至1990年1月,美国制造业(包括建筑业)的就业水平比1980年降低了3%,(100万人),而服务业的就业率却增加了3%,(2000万人)。从制造业向服务业转移的工人数目也不断上升。一些部门在制造业中的比重有较大增加。 展开更多
关键词 服务地理学 经济学 前景
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农药——利大于弊的典型
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作者 Robert.w.daniels 梁中民 《农药译丛》 1989年第5期16-23,共8页
农药安全性是一个十分激动人的情绪的、一直受到社会各界团体指责、至今农药工业界为之勉强维护的主题。为了避免任何混乱,可能最好是首先将农药的定义明确下来。农药一般的定义是指用于杀死、控制或消灭任何对于人类所利用的农作物、... 农药安全性是一个十分激动人的情绪的、一直受到社会各界团体指责、至今农药工业界为之勉强维护的主题。为了避免任何混乱,可能最好是首先将农药的定义明确下来。农药一般的定义是指用于杀死、控制或消灭任何对于人类所利用的农作物、家畜或人类环境的有害生物的化学品,这一定义范围包括了所有的以它们的用途命名的较为特殊的化合物,例如:杀虫剂、杀菌剂、除草剂、杀线虫剂、杀藻剂、杀软体动物剂、植物生长调节剂等。 展开更多
关键词 农药 安全性
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Phenology of high-arctic butterflies and their floral resources: Species-specific responses to climate change 被引量:2
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作者 Toke T.HФYE Anne ESKILDSEN +3 位作者 Rikke R. HANSEN Joseph J.BOwDEN Niels M.SCHMIDT w.daniel KISSLING 《Current Zoology》 SCIE CAS CSCD 2014年第2期243-251,共9页
Current global warming is particularly pronounced in the Arctic and arthropods are expected to respond rapidly to these changes. Long-term studies of individual arthropod species from the Arctic are, however, virtuall... Current global warming is particularly pronounced in the Arctic and arthropods are expected to respond rapidly to these changes. Long-term studies of individual arthropod species from the Arctic are, however, virtually absent. We examined butterfly specimens collected from yellow pitfall traps over 14 years (1996-2009) at Zackenberg in high-arctic, north-east Greenland. Specimens were previously sorted to the family level. We identified them to the species level and examined long-term species-specific phenological responses to recent summer wanning. Two species were rare in the samples (Polaris fritillary Boloria polaris and Arctic blue Plebejus glandon) and statistical analyses of phenological responses were therefore restricted to the two most abundant species (Arctic fritillary, B. chariclea and Northern clouded yellow Colias hecla). Our analyses demonstrated a trend towards earlier flight seasons in B. chariclea, but not in C. hecla. The timing of onset, peak and end of the flight season in B. chariclea were closely related to snowmelt, July temperature and their interaction, whereas onset, peak and end of the flight season in C. hecla were only related to timing of snowmelt. The duration of the butterfly flight season was significantly positively related to the temporal overlap with floral resources in both butterfly species. We further demonstrate that yellow pitfall traps are a useful alternative to transect walks for butterfly recording in tundra habitats. More phenological studies of Arctic arthropods should be carded out at the species level and ideally be analysed in context with interacting species to assess how ongoing climate change will affect Arctic biodiversity in the near future [Current Zoology 60 (2): 243-251, 2014]. 展开更多
关键词 ARCTIC ARTHROPOD Flight period GREENLAND Pitfall trap Zackenberg
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How does stiffness of trabecular meshwork affect outflow resistance in human eyes?
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作者 Fan Yuan Lucinda J.Camras +2 位作者 w.daniel Stamer David Epstein Pedro Gonzalez 《医用生物力学》 EI CAS CSCD 北大核心 2013年第S1期86-88,共3页
Purpose Ocular hypertension is the primary risk factor for development of glaucoma and the only modifiable endpoint<sup>[1,2]</sup>.Clinical trials involving thousands of patients have shown consistently t... Purpose Ocular hypertension is the primary risk factor for development of glaucoma and the only modifiable endpoint<sup>[1,2]</sup>.Clinical trials involving thousands of patients have shown consistently that lowering intraocular pressure(IOP)in those with glaucoma,whether or not their IOP is above normal,slows vision loss.IOP elevation is the result of diminished outflow facility in the conventional outflow pathway;and the highest resistance to aqueous humor outflow resides in the juxtacanalicular tissue(JCT)layer of trabecular meshwork(TM)and the inner wall of Schlemm’s canal(SC).However,mechanisms of outflow facility decrease in glaucomatous eyes remain to be determined. 展开更多
关键词 OUTFLOW TRABECULAR glaucoma INTRAOCULAR facility consistently STIFFNESS CANAL lowering ENDPOINT
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Scaling Notebooks as Re-configurable Cloud Workflows
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作者 Yuandou wang Spiros Koulouzis +5 位作者 Riccardo Bianchi Na Li Yifang Shi Joris Timmermans w.daniel Kissling Zhiming Zhao 《Data Intelligence》 EI 2022年第2期409-425,共17页
Literate computing environments,such as the Jupyter(i.e.,Jupyter Notebooks,JupyterLab,and JupyterHub),have been widely used in scientific studies;they allow users to interactively develop scientific code,test algorith... Literate computing environments,such as the Jupyter(i.e.,Jupyter Notebooks,JupyterLab,and JupyterHub),have been widely used in scientific studies;they allow users to interactively develop scientific code,test algorithms,and describe the scientific narratives of the experiments in an integrated document.To scale up scientific analyses,many implemented Jupyter environment architectures encapsulate the whole Jupyter notebooks as reproducible units and autoscale them on dedicated remote infrastructures(e.g.,highperformance computing and cloud computing environments).The existing solutions are stl limited in many ways,e.g.,1)the workflow(or pipeline)is implicit in a notebook,and some steps can be generically used by different code and executed in parallel,but because of the tight cell structure,all steps in the Jupyter notebook have to be executed sequentially and lack of the flexibility of reusing the core code fragments,and 2)there are performance bottlenecks that need to improve the parallelism and scalability when handling extensive input data and complex computation.In this work,we focus on how to manage the workflow in a notebook seamlessly.We 1)encapsulate the reusable cells as RESTful services and containerize them as portal components,2)provide a composition tool for describing workflow logic of those reusable components,and 3)automate the execution on remote cloud infrastructure.Empirically,we validate the solution's usability via a use case from the Ecology and Earth Science domain,illustrating the processing of massive Light Detection and Ranging(LiDAR)data.The demonstration and analysis show that our method is feasible,but that it needs further improvement,especially on integrating distributed workflow scheduling,automatic deployment,and execution to develop as a mature approach. 展开更多
关键词 Scientific experiments Jupyter Notebooks Workflow management Ecosystem structure data products CLOUD SCALABILITY
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美国弗吉尼亚矿区土地复垦重组土壤的温室试验
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作者 雷永振 朱荫楣 +1 位作者 M.M.ALLEY w.L.daniels 《土壤肥料》 CSCD 1995年第5期1-5,共5页
在美国弗吉尼亚州的一个金属矿区进行土地复垦,其废弃物矿砂和矿泥的不良质地和磷素缺乏是恢复土地生产力的两大限制因素。通过温室盆栽试验,选择矿砂与矿泥重组土壤的最佳比例和加入磷素的最佳用量,为下一步进行的田间试验和土地复... 在美国弗吉尼亚州的一个金属矿区进行土地复垦,其废弃物矿砂和矿泥的不良质地和磷素缺乏是恢复土地生产力的两大限制因素。通过温室盆栽试验,选择矿砂与矿泥重组土壤的最佳比例和加入磷素的最佳用量,为下一步进行的田间试验和土地复垦工程的实施提供基础资料。 展开更多
关键词 土地复垦 矿砂 矿泥 磷素 土壤肥力
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Predicting release and aquatic effects of total dissolved solids from Appalachian USA coal mines 被引量:1
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作者 w.L.daniels C.E.Zipper Z.w.Orndorff 《International Journal of Coal Science & Technology》 EI CAS 2014年第2期152-162,共11页
Appalachian USA coal mines have been implicated as major stressors to aquatic life in headwater streams via discharge of total dissolved solids(TDS).This paper summarizes column leaching studies of spoils(n>50)and ... Appalachian USA coal mines have been implicated as major stressors to aquatic life in headwater streams via discharge of total dissolved solids(TDS).This paper summarizes column leaching studies of spoils(n>50)and refuse and TDS effects on local water quality and biotic response.The initial pH of most materials is near-neutral.Initial specific conductance(SC)values range from 500-1,000 to >3,000 μs/cm,but 2/3 of materials drop below 500 ls/cm after several pore volumes of leaching.Studies of mining-influenced streams have found altered aquatic life,relative to natural conditions with no mining influence,at SC ranging from-200 to-700 ls/cm with depressed aquatic life consistently associated with elevated TDS;mechanisms causing such effects are under investigation.We suggest that active mine operations should be modified to place high TDS producing materials in ways that reduce contact with percolating drainage waters. 展开更多
关键词 Mine spoil Weathering-Acid base accounting Water quality Valley fills
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获得性心瓣膜病的影像学检查
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作者 M.weise R.weise +1 位作者 w.G.daniel 宋玉娥 《德国医学》 CAS 1995年第3期151-152,共2页
本文综述了临床上关于获得性心瓣膜病的影像学检查方法,并阐述了各方法的价值,费用和应用情况,最后提出了逐步诊断法。传统的X线胸片 疑有心瓣膜病时,除详细询问病史、全面体检和ECG检查外,还需拍胸片。胸片需包括二个平面,即后前位和... 本文综述了临床上关于获得性心瓣膜病的影像学检查方法,并阐述了各方法的价值,费用和应用情况,最后提出了逐步诊断法。传统的X线胸片 疑有心瓣膜病时,除详细询问病史、全面体检和ECG检查外,还需拍胸片。胸片需包括二个平面,即后前位和侧位。它可了解心脏的大小和形态、肺血情况、肺和胸膜的变化及近心血管的状况。心脏横径与整个胸廊直径之比仍为判断心脏大小的实用方法。 展开更多
关键词 心脏瓣膜疾病 CT 超声心动图 核磁共振成像
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