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Prevalence, risk factors, clinical course, and outcome of acute kidney injury in Chinese intensive care units: a prospective cohort study 被引量:43
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作者 WEN Ying JIANG Li +21 位作者 XU Yuan QIAN Chuan-yun LI Shu-sheng QIN Tie-he CHEN Er-zhen LIN Jian-dong AI Yu- hang WU Da-wei WANG Yu-shan SUN Ren-hua HU Zhen-jie CAO Xiang-yuan ZHOU Fa-chun HE Zhen-yang ZHOU Li-hua AN You-zhong KANG Yan MA Xiao-chun YU Xiang-you ZHAO Ming-yan XI Xiu-ming DU Bin 《Chinese Medical Journal》 SCIE CAS CSCD 2013年第23期4409-4416,共8页
Background Acute kidney injury (AKI) has been recognized as a major healthcare problem affecting millions of patients worldwide.However,epidemiologic data concerning AKI in China are still lacking.The objectives of ... Background Acute kidney injury (AKI) has been recognized as a major healthcare problem affecting millions of patients worldwide.However,epidemiologic data concerning AKI in China are still lacking.The objectives of this study were to characterize AKI defined by RIFLE criteria,assess the association with hospital mortality,and evaluate the impact of AKI in the context of other risk factors.Methods This prospective multicenter observational study enrolled 3,063 consecutive patients from 1 July 2009 to 31 August 2009 in 22 ICUs across China's Mainland.We excluded patients who were admitted for less than 24 hours (n=1623),younger than 18 years (n=127),receiving chronic hemodialysis (n=29),receiving renal transplantation (n=1) and unknown reasons (n=28).There were 1255 patients in the final analysis.AKI was diagnosed and classified according to RIFLE criteria.Results There were 396 patients (31.6%) who had AKI,with RIFLE maximum class R,I,and F in 126 (10.0%),91 (7.3%),and 179 (14.3%) patients,respectively.Renal function deteriorated in 206 patients (16.4%).In comparison with non AKI patients,patients in the risk class on ICU admission were more likely to progress to the injury class (odds ratio (OR) 3.564,95% confidence interval (CI) 1.706-7.443,P =0.001],while patients in the risk class (OR 5.215,95% CI 2.798-9.719,P <0.001) and injury class (OR 13.316,95% CI 7.507-23.622,P <0.001) had a significantly higher probability of deteriorating into failure class.The adjusted hazard ratios for 90-day mortality were 1.884 for the risk group,3.401 for the injury group,and 5.306 for the failure group.Conclusions The prevalence of AKI was high among critically ill patients in Chinese ICUs.In comparison with non-AKI patients,patients with RIFLE class R or class I on ICU admission were more susceptibility to progression to class I or class F.The RIFLE criteria were robust and correlated well with clinical deterioration and mortality. 展开更多
关键词 acute kidney injury intensive care units MORTALITY PREVALENCE risk factors
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Decrease-radix design principle for carrying/borrowing free multi-valued and application in ternary optical computer 被引量:42
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作者 YAN JunYong JIN Yi ZUO KaiZhong 《Science in China(Series F)》 2008年第10期1415-1426,共12页
In this paper a new theory referred to as the decrease-radix design (DRD) is proposed, which is found in the research of logic units of ternary (tri-valued) optical computer. Based on the theory proposed, the prin... In this paper a new theory referred to as the decrease-radix design (DRD) is proposed, which is found in the research of logic units of ternary (tri-valued) optical computer. Based on the theory proposed, the principles and the regulations of the DRD for making operation units of multi-valued operation with carrying/borrowing free are also presented. The research work has come to the following important conclusion: let D be a special state contained in n physical informative states, then one may figure out any multi-valued processors within n^(n×n) carrying/borrowing free n-valued units by the composition some of n×n×(n-1) simplest basic operating units according to the regulations of DRD proposed in this paper. The detailed systematic way of our design regulations is highlighted step by step in the paper with an example of design of a tri-valued logic optical operating unit. The real architecture, the procedure, and the experimental results of our sample in tri-valued logic operating unit are given. Finally, a re-constructible model of ternary logical optical processor is introduced. The theory proposed in the paper has laid down a solid foundation for the design of re-constructible carrying/borrowing free operating units in ternary optical computers and can be widely used as the designing reference in a variety of multi-valued logic operating units. 展开更多
关键词 carrying/borrowing free operating units decrease-radix design re-constructible ternary optical computer
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Reliability and validity of the Chinese version of the Readiness for Hospital Discharge Scale-Parent Form in parents of preterm infants 被引量:33
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作者 Yongfeng Chen Jinbing Bai 《International Journal of Nursing Sciences》 2017年第2期88-93,共6页
Background: The Readiness for Hospital Discharge Scale (RHDS)-Parent Form shows satisfactory reli-ability and validity to assess the readiness of parents to take care of their children discharged from hospitals in Wes... Background: The Readiness for Hospital Discharge Scale (RHDS)-Parent Form shows satisfactory reli-ability and validity to assess the readiness of parents to take care of their children discharged from hospitals in Western countries. However, the reliability and validity of this instrument has not been evaluated in Chinese populations.Objectives: Evaluate the psychometric features of the RHDS-Parent Form among Chinese parents of preterm infants. Methods: The RHDS-Parent Form was translated into a Chinese version following an international in-strument translation guideline. A total of 168 parents with preterm infants were recruited from the neonatal intensive care units of two tertiary-level hospitals in China. The internal consistency of this measure was assessed using the Cronbach's a coefficient;confirmatory factor analysis was conducted to evaluate the construct validity;and Pearson correlation coefficient was used to report the convergent validity. Results: The Chinese version of RHDS (C-RHDS)-Parent Form included 22 items with 4 subscales, ac-counting for 56.71% of the total variance. The C-RHDS-Parent Form and its subscales showed good reliability (Cronbach's a values 0.78-0.92). This measure and its subscales showed positive correlations with the score of Quality of Discharge Teaching Scale. Conclusion: The factor structure of C-RHDS-Parent Form is partially consistent with the original English version. Future studies are needed to explore the factors within this measure before it is widely used in Chinese clinical care settings. 展开更多
关键词 PARENT Preterm infant Neonatal intensive care units Readiness for hospital discharge Scale-Parent Form Psychometric property Instrument translation
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The assessment of soil loss by water erosion in China 被引量:24
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作者 Baoyuan Liu Yun Xie +10 位作者 Zhiguang Li Yin Liang Wenbo Zhang Suhua Fu Shuiqing Yin Xin Wei Keli Zhang Zhiqiang Wang Yingna Liu Ying Zhao Qiankun Guo 《International Soil and Water Conservation Research》 SCIE CSCD 2020年第4期430-439,共10页
Soil erosion is a major environmental problem in China.Planning for soil erosion control requires accurate soil erosion rate and spatial distribution information.The aim of this article is to present the methods and r... Soil erosion is a major environmental problem in China.Planning for soil erosion control requires accurate soil erosion rate and spatial distribution information.The aim of this article is to present the methods and results of the national soil erosion survey of China completed in 2011.A multi-stage,unequal probability,systematic area sampling method was employed.A total of 32,948 sample units,which were either 0.2-3 km2 small catchments or 1 km2 grids,were investigated on site.Soil erosion rates were calculated with the Chinese Soil Loss Equation in 10 m by 10 m grids for each sample unit,along with the area of soil loss exceeding the soil loss tolerance and the proportion of area in excess of soil loss tolerance relative to the total land area of the sample units.Maps were created by using a spatial interpolation method at national,river basin,and provincial scales.Results showed that the calculated average soil erosion rate was 5 t ha-1 yr-1 in China,and was 18.2 t ha-1 yr-1 for sloped,cultivated cropland.Intensive soil erosion occurred on cropland,overgrazing grassland,and sparsely forested land.The proportions of soil loss tolerance exceedance areas of sample units were interpolated through the country in 250 m grids.The national average ratio was 13.5%,which represents the area of land in China that requires the implementation of soil conservation practices.These survey results and the maps provide the basic information for national conservation planning and policymaking. 展开更多
关键词 National soil erosion survey CSLE Sample units Chinese soil loss map Soil erosion rate Ratio of soil erosion area
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ADMM-based Distributed State Estimation for Integrated Energy System 被引量:24
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作者 Yaxin Du Wen Zhang Tingting Zhang 《CSEE Journal of Power and Energy Systems》 SCIE CSCD 2019年第2期275-283,共9页
In order to have an accurate knowledge of system-wide operation states,it is necessary to perform state estimation for the integrated energy system(IES)as the basis of energy man-agement and control.Centralized state ... In order to have an accurate knowledge of system-wide operation states,it is necessary to perform state estimation for the integrated energy system(IES)as the basis of energy man-agement and control.Centralized state estimation is practically infeasible for IES due to the unreliability of communication,the barrier on privacy,and the large scale of integrated systems.This paper proposes a distributed state estimation algorithm based on the alternating direction method of multipliers(ADMM)for IES containing electricity,heat,and natural gas.Various coupling units are taken into full consideration in modeling of IES state estimation to reflect the harmonization of multi energy.On the basis of bilinear measurement model,the state estimation considering nonlinear measurements can be replaced by an equivalent three-stage problem containing two linear state estimations and an intermediate transformation to avoid non-convex optimization.The three-stage procedure for IES state estimation can be further decoupled over three sub-systems with coordination on coupling units,yielding a fully distributed scheme based on ADMM.A modified ADMM with the self-adjusting penalty parameter is also adopted to enhance the convergence.Simulation results demonstrate the validity and superiority of the proposed algorithm. 展开更多
关键词 Alternating direction method of multipliers coupling units distributed state estimation integrated energy system
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On Structure,production,and market of bamboo-based panels in China 被引量:23
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作者 蒋身学 张齐生 姜树海 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第2期151-156,165,共6页
Since bamboo has the advantages of straight grain, beautiful color, high strength and toughness, and excellent abrasion resistance, bamboo-based panels have been widely used in the fields of vehicle, construction, shi... Since bamboo has the advantages of straight grain, beautiful color, high strength and toughness, and excellent abrasion resistance, bamboo-based panels have been widely used in the fields of vehicle, construction, ship building, furniture, and decoration to partly take the place of wood, steel, plastic etc in China. This paper briefly described the basic component units, including strip, sliver, and particle, of bamboo-based panel and pointed out that to design the structure of bamboo-based panels should follow the principle of symmetric structure, surface forming method, and structuring principle of equalizing stress. According to the processing methods and formation of component units, the authors classified the bamboo-based panels in China into 13 types and presented the manufacturing technique and uses of the bamboo products, such as plybamboo, bamboo flooring, and bamboo-wood composite products in detail. In the last part of the paper, much information were offered on the output, market, and selling prospect of each type of bamboo-based panels. 展开更多
关键词 Bamboo-based panel Component units STRUCTURE Production process MARKET
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做好文稿的退修工作 被引量:23
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作者 曹作华 田力 《编辑学报》 CSSCI 北大核心 2001年第6期351-352,共2页
为了确保科技信息准确、快速、广泛地传播 ,编辑在做文稿退修时须把握好以下几点 :1)注意对文稿内容、结构及统计数据的审查与质疑。 2 )注意对文稿标准化的审查与修改 ,使题名、摘要、关键词、名词术语、计量单位等符合科技期刊的标准... 为了确保科技信息准确、快速、广泛地传播 ,编辑在做文稿退修时须把握好以下几点 :1)注意对文稿内容、结构及统计数据的审查与质疑。 2 )注意对文稿标准化的审查与修改 ,使题名、摘要、关键词、名词术语、计量单位等符合科技期刊的标准化规范化要求。 3 )尊重作者劳动 ,退修意见力求准确、全面、具体 ,要求明确 。 展开更多
关键词 科技论文 文稿退修 编辑工作 文稿审查
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Ophiolites of the Central Asian Orogenic Belt:Geochemical and petrological characterization and tectonic settings 被引量:16
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作者 Harald Furnes Inna Safonova 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1255-1284,共30页
We present a compilation of published data(field,petrography,ages and geochemistry)from 73 ophiolitic complexes of the Central Asian Orogenic Belt.The ophiolitic complexes,ranging in age from Neoproterozoic to Triassi... We present a compilation of published data(field,petrography,ages and geochemistry)from 73 ophiolitic complexes of the Central Asian Orogenic Belt.The ophiolitic complexes,ranging in age from Neoproterozoic to Triassic.have been geochemically classified as subduction-related and subductionunrelated categories applying recent,well-established discrimination diagrams.The subductionunrelated category is further subdivided into Mid-Ocean Ridge type(MOR),a common rift-drift stage and Plume type,and the subduction-related category is subdivided into Backarc(BA),Forearc(FA).Backarc to Forearc(BA-FA)and Volcanic Arc(VA)types.The four subduction-related types define highly different geochemical features,with the BA and FA types defining end members showing subduction influence of 10%-100%and 90%-100%subduction influence,respectively,and the two other types(BAFA and VA)define values between the two end members.The subduction-related category comprises79%of the examined ophiolites,of which the BA type ophiolites is by far the dominant group,followed by the BA-FA type,and with FA and VA types as subordinate groups.The Neoproterozoic and Ordovician complexes exhibit the highest,whereas those of Silurian age exhibit the lowest subduction-influence.Of the remaining 21%subduction-unrelated ophiolites,the MOR type dominates.Both the subductionrelated and subduction-unrelated types,in particular the latter,are commonly associated with alkaline basalts taken to represent ocean island magmatism.Harzburgite,dunite,gabbro and basalt are the common lithologies in all ophiolite types,whereas the BA-FA,FA and VA types generally contain intermediate to felsic rocks,and in the FA type boninites occur.The subduction-related ophiolites types generally show low metamorphic grade,whereas greenschist.amphibolite and blueschist grades occur in the subduction-unrelated and BA types.The highly different subduction contribution(from 0 to 100%in the MOR and FA,respectively),attest to variable dips of the subducting slab,as well as variable flux of s 展开更多
关键词 GEOCHEMICAL classification Subduction-unrelated units Subduction-related units SUBDUCTION fingerprint Intra-plate MAGMAS Arc erosion
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New injury severity score(NISS)outperforms injury severity score(ISS)in the evaluation of severe blunt trauma patients 被引量:20
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作者 Hui Li Yue-Feng Ma 《Chinese Journal of Traumatology》 CAS CSCD 2021年第5期261-265,共5页
Purpose:The injury severity score(ISS)and new injury severity score(NISS)have been widely used in trauma evaluation.However,which scoring system is better in trauma outcome prediction is still disputed.The purpose of ... Purpose:The injury severity score(ISS)and new injury severity score(NISS)have been widely used in trauma evaluation.However,which scoring system is better in trauma outcome prediction is still disputed.The purpose of this study is to evaluate the value of the two scoring systems in predicting trauma outcomes,including mortality,intensive care unit(ICU)admission and ICU length of stay.Methods:The data were collected retrospectively from three hospitals in Zhejiang province,China.The comparisons of NISS and ISS in predicting outcomes were performed by using receiver operator characteristic(ROC)curves and Hosmer-Lemeshow statistics.Results:A total of 1825 blunt trauma patients were enrolled in our study.Finally,1243 patients were admitted to ICU,and 215 patients died before discharge.The ISS and NISS were equivalent in predicting mortality(area under ORC curve[AUC]:0.886 vs.0.887,p=0.9113).But for the patients with ISS>25,NISS showed better performance in predicting mortality.NISS was also significantly better than ISS in predicting ICU admission and prolonged ICU length of stay.Conclusion:NISS outperforms ISS in predicting the outcomes for severe blunt trauma and can be an essential supplement of ISS.Considering the convenience of NISS in calculation,it is advantageous to promote NISS in China's primary hospitals. 展开更多
关键词 Injury severity score New injury severity score MORTALITY Intensive care units
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NUMERICAL SIMULATION OF TWO-DIMENSIONAL OVERTOPPING AGAINST SEAWALLS ARMORED WITH ARTIFICIAL UNITS IN REGULAR WAVES 被引量:17
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作者 LU Yong-jin LIU Hua +1 位作者 WU Wei ZHANG Jiu-shan 《Journal of Hydrodynamics》 SCIE EI CSCD 2007年第3期322-329,共8页
A new mathematical model for the overtopping against seawalls armored with artificial units in regular waves was established. The 2-D numerical wave flume, based on the Reynolds Averaged Navier-Stokes (RANS) equatio... A new mathematical model for the overtopping against seawalls armored with artificial units in regular waves was established. The 2-D numerical wave flume, based on the Reynolds Averaged Navier-Stokes (RANS) equations and the standard κ-ε turbulence model, was developed to simulate the turbulent flows with the free surface, in which the Volume Of Fluid (VOF) method was used to handle the large deformation of the free surface and the relaxation approach of combined wave generation and absorbing was implemented. In order to consider the effects of energy dissipation due to the armors on a slope seawall, a porous media model was proposed and implemented in the numerical wave flume. A series of physical model experiments were carried out in the same condition of the numerical simulation to determine the drag coefficient in the porous media model in terms of the overtopping discharge. Compared the computational value of overtopping over the seawall with the experimental data, the values of the effective drag coefficient was calibrated for the layers of blocks at different locations along the seawalls. 展开更多
关键词 porous media OVERTOPPING SEAWALL armored units 2-D numerical wave flume regular waves
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Factors affecting the seismic behavior of segmental precast bridge columns 被引量:17
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作者 Haitham DAWOOD Mohamed ELGAWADY Joshua HEWES 《Frontiers of Structural and Civil Engineering》 CSCD 2014年第4期388-398,共11页
This manuscript discusses the design parameters that potentially affect the lateral seismic response of segmental precast post-tensioned bridge piers. The piers consist ofprecast circular cross section segments stacke... This manuscript discusses the design parameters that potentially affect the lateral seismic response of segmental precast post-tensioned bridge piers. The piers consist ofprecast circular cross section segments stacked one on top of the other with concentric tendons passing through ducts made in the segments during casting. The bottommost segments of the piers were encased in steel tubes to enhance ductility and minimize damage. An FE model was used to investigate different design parameters and how they influence the lateral force - displacement response of the piers. Design parameters investigated included the initial post-tensioning stress as a percentage of the tendon yield stress, the applied axial stresses on concrete due to post-tensioning, pier aspect ratios, construction details, steel tube thicknesses, and internal mild steel rebar added as energy dissipaters. Based on the data presented, an initial tendon stress in the range of 40%-60% of its yield stress and initial axial stress on concrete of approximately 20% of the concrete's characteristic strength is appropriate for most typical designs. These design values will prevent tendon yielding until lateral drift angle reaches approximately 4.5%. Changing the steel tube thickness, height, or a combination of both proved to be an effective parameter that may be used to reach a target performance level at a specific seismic zone. 展开更多
关键词 finite element analysis CONCRETE precast units BRIDGES
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Severe sepsis and septic shock in the elderly:An overview 被引量:15
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作者 Prashant Nasa Deven Juneja Omender Singh 《World Journal of Critical Care Medicine》 2012年第1期23-30,共8页
The incidence of severe sepsis and septic shock is increasing in the older population leading to increased admissions to the intensive care units(ICUs). The elderly are predisposed to sepsis due to co-existing comorbi... The incidence of severe sepsis and septic shock is increasing in the older population leading to increased admissions to the intensive care units(ICUs). The elderly are predisposed to sepsis due to co-existing comorbidities, repeated and prolonged hospitalizations, reduced immunity, functional limitations and above all due to the effects of aging itself. A lower threshold and a higher index of suspicion is required to diagnose sepsis in this patient population because the initial clinical picture may be ambiguous, and aging increases the risk of a sudden deterioration in sepsis to severe sepsis and septic shock. Management is largely based on standard international guidelines with a few modifications. Age itself is an independent risk factor for death in patients with severe sepsis, however, many patients respond well to timely and appropriate interventions. The treatment should not be limited or deferred in elderly patients with severe sepsis only on the grounds of physician prejudice, but patient and family preferences should also be taken into account as the outcomes are not dismal. Future investigations in the management of sepsis should not only target good functional recovery but also ensure social independence and quality of life after ICU discharge. 展开更多
关键词 ELDERLY patients INTENSIVE care units OUTCOME SEVERE SEPSIS
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蛇形管式高压加热器在大型火电机组中的应用 被引量:16
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作者 凌峰 《电站辅机》 2014年第3期5-7,28,共4页
随着机组容量增大,加热器的设计参数也在不断地提高,传统U形管式高压加热器的设计难度越来越大,而蛇形管式高压加热器,有着良好的热弹性及失效率较低的特点,能更好地满足当前辅机设备高参数的设计需求。在大型机组中推广采用蛇形管式加... 随着机组容量增大,加热器的设计参数也在不断地提高,传统U形管式高压加热器的设计难度越来越大,而蛇形管式高压加热器,有着良好的热弹性及失效率较低的特点,能更好地满足当前辅机设备高参数的设计需求。在大型机组中推广采用蛇形管式加热器结构,为提高加热器的可靠性,提供了新的设计思路。 展开更多
关键词 机组 高压加热器 换热管 U形管 蛇形管 设计 参数 应用
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Ansys软件中的单位制分析 被引量:15
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作者 李如忠 《机械设计与制造》 北大核心 2008年第2期90-91,共2页
在用Ansys进行有限元分析时不需要输入单位,但使用的单位必须统一。通过量纲分析说明了Ansys中保证单位统一的方法。并编制了计算机程序,方便在Ansys中的单位设置和选择。并说明了如何确定采用英制单位的分析算例的输出结果的单位。
关键词 ANSYS 有限元分析 单位 量纲
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Advances in the development of power supplies for the Internet of Everything 被引量:16
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作者 Xiayue Fan Xiaorui Liu +2 位作者 Wenbin Hu Cheng Zhong Jun Lu 《InfoMat》 SCIE CAS 2019年第2期130-139,共10页
The Internet of Everything(IoE),which aims to realize information exchange and communications for anything with the Internet,has revolutionized our modern world.Serving as the driving force for devices in the IoE netw... The Internet of Everything(IoE),which aims to realize information exchange and communications for anything with the Internet,has revolutionized our modern world.Serving as the driving force for devices in the IoE network,power supply systems play a fundamental role in the development of the IoE.However,due to the complexity,multifunctionality and wide-scale deployment of diverse applications,power supply systems face great challenges,including distribution,connection,charging technologies,and management.In this review,some challenges and advances in the development of both power supply systems and their units are presented.In the overall system-level field,establishing sustainable and maintenancefree power supply systems through wireless connections,efficient power management and integrated energy harvesting and storage systems is highlighted.Additionally,the main performance metrics of power supply units are discussed,including energy density,service life,and self-power ability.In addition,some directions of power quality assessment for both the system and unit levels of power supply systems are presented,aiming to provide insight into the future development of high-performance power supply systems for the IoE. 展开更多
关键词 assessment of power supply systems Internet of Everything power supply systems power supply units
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论意义的两个来源和语言哲学的任务——从语言游戏规则和单位的还原说起 被引量:13
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作者 陈保亚 《北京大学学报(哲学社会科学版)》 CSSCI 北大核心 2006年第1期32-39,共8页
维特根斯坦《哲学研究》中意义即用法的理论只是意义来源的一个方面。由对指称的概括形成的意义是意义的另一个来源。自然语言是通过有限单位和游戏规则生成无限句子的活动,学会语言游戏必须掌握这些有限的单位和游戏规则,而提取这些单... 维特根斯坦《哲学研究》中意义即用法的理论只是意义来源的一个方面。由对指称的概括形成的意义是意义的另一个来源。自然语言是通过有限单位和游戏规则生成无限句子的活动,学会语言游戏必须掌握这些有限的单位和游戏规则,而提取这些单位和游戏规则需要平行周遍对比。对平行周遍对比的进一步分析可以看出,意义用法论和意义概括论这两个意义的来源不能相互替代,都是初始的,这就决定了语言哲学的任务不仅仅是弄懂词的用法,更重要的是要通过对概括方式和概括过程的分析来回答和认识论有关的问题。 展开更多
关键词 语言游戏 单位 规则 词的用法 词的意义
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DEA方法的Excel实现 被引量:12
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作者 王斌会 《统计与决策》 CSSCI 北大核心 2006年第5期143-144,共2页
关键词 DEA方法 Excel C^2R模型 C^2GS^2模型 数据包络分析 units 相对有效性 决策单元 运筹学
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Reduced parameter model on trajectory tracking data with applications 被引量:14
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作者 王正明 朱炬波 《Science China(Technological Sciences)》 SCIE EI CAS 1999年第2期190-199,共10页
The data fusion in tracking the same trajectory by multi-measurement unit (MMU) is considered. Firstly, the reduced parameter model (RPM) of trajectory parameter (TP), system error and random error are presented, and ... The data fusion in tracking the same trajectory by multi-measurement unit (MMU) is considered. Firstly, the reduced parameter model (RPM) of trajectory parameter (TP), system error and random error are presented, and then the RPM on trajectory tracking data (TTD) is obtained, a weighted method on measuring elements (ME) is studied and criteria on selection of ME based on residual and accuracy estimation are put forward. According to RPM, the problem about selection of ME and self-calibration of TTD is thoroughly investigated. The method improves data accuracy in trajectory tracking obviously and gives accuracy evaluation of trajectory tracking system simultaneously. 展开更多
关键词 TRAJECTORY tracking data REDUCED PARAMETER model selection of measurement units SELF-CALIBRATION ACCURACY evaluation.
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The growth mechanism of hydrotalcite crystal 被引量:15
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作者 WU JianSong XIAO YingKai +1 位作者 WAN JianYu WEN LiRong 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第4期872-878,共7页
From the point of growth units, the growth mechanism of hydrotalcite (HT) crystal is investigated in this paper. Results show that the growth morphology of HT is consistent with the model of anion coordination polyhed... From the point of growth units, the growth mechanism of hydrotalcite (HT) crystal is investigated in this paper. Results show that the growth morphology of HT is consistent with the model of anion coordination polyhedron growth units. The Raman shift of growth solutions of HT, Cu-HTlc, and Cu-Zn-HTlc are monitored using Raman spectroscopy. In the experiment, the growth units of Mg-Al-hydrotalcite are [Mg-(OH)6]4- and [Al-(OH)6]3-, and the growth units of Cu-Htlc and Cu-Zn-HTlc are [Mg-(OH)6]4- and [Al-(OH)6]3-, respectively. The growth process of hydrotalcite is as follows: growth units first incorpo- rate into metal layers, then metal layers adsorb An- and H2O, and the growth units incorporate into layer compounds according to this rule. Growth units will have different incorporations and growth morphologies caused by different growth surroundings. Furthermore, the reason why Cu-HTlc is difficult to synthesize is also interpreted in this paper. 展开更多
关键词 model of anion coordination polyhedron growth units growth mechanism growth morphology Jahn-Teller effect
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Integrated-resonant metadevices:a review 被引量:14
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作者 Jin Yao Rong Lin +1 位作者 Mu Ku Chen Din Ping Tsai 《Advanced Photonics》 SCIE EI CAS CSCD 2023年第2期7-33,共27页
Integrated-resonant units(IRUs),associating various meta-atoms,resonant modes,and functionalities into one supercell,have been promising candidates for tailoring composite and multifunctional electromagnetic responses... Integrated-resonant units(IRUs),associating various meta-atoms,resonant modes,and functionalities into one supercell,have been promising candidates for tailoring composite and multifunctional electromagnetic responses with additional degrees of freedom.Integrated-resonant metadevices can overcome many bottlenecks in conventional optical devices,such as broadband achromatism,efficiency enhancement,response selectivity,and continuous tunability,offering great potential for performant and versatile application scenarios.We focus on the recent progress of integrated-resonant metadevices.Starting from the design principle of IRUs,a variety of IRU-based characteristics and subsequent practical applications,including achromatic imaging,light-field sensing,polarization detection,orbital angular momentum generation,metaholography,nanoprinting,color routing,and nonlinear generation,are introduced.Existing challenges in this field and opinions on future research directions are also provided. 展开更多
关键词 integrated-resonant units metadevices metasurfaces nanophotonic devices planar optics
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