期刊文献+
共找到1,198篇文章
< 1 2 60 >
每页显示 20 50 100
Key-Value Store Coupled with an Operating System for Storing Large-Scale Values
1
作者 Jeonghwan Im Hyuk-Yoon Kwon 《Computers, Materials & Continua》 SCIE EI 2022年第11期3333-3350,共18页
The key-value store can provide flexibility of data types because it does not need to specify the data types to be stored in advance and can store any types of data as the value of the key-value pair.Various types of ... The key-value store can provide flexibility of data types because it does not need to specify the data types to be stored in advance and can store any types of data as the value of the key-value pair.Various types of studies have been conducted to improve the performance of the key-value store while maintaining its flexibility.However,the research efforts storing the large-scale values such as multimedia data files(e.g.,images or videos)in the key-value store were limited.In this study,we propose a new key-value store,WR-Store++aiming to store the large-scale values stably.Specifically,it provides a new design of separating data and index by working with the built-in data structure of the Windows operating system and the file system.The utilization of the built-in data structure of the Windows operating system achieves the efficiency of the key-value store and that of the file system extends the limited space of the storage significantly.We also present chunk-based memory management and parallel processing of WR-Store++to further improve its performance in the GET operation.Through the experiments,we show that WR-Store++can store at least 32.74 times larger datasets than the existing baseline key-value store,WR-Store,which has the limitation in storing large-scale data sets.Furthermore,in terms of processing efficiency,we show that WR-Store++outperforms not only WR-Store but also the other state-ofthe-art key-value stores,LevelDB,RocksDB,and BerkeleyDB,for individual key-value operations and mixed workloads. 展开更多
关键词 Key-value stores large-scale values chunk-based memory management parallel processing
在线阅读 下载PDF
Geometric Analysis of Singularity for Single-Gimbal Control Moment Gyro Systems 被引量:8
2
作者 汤亮 徐世杰 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2005年第4期295-303,共9页
This research is focused on the singularity analysis for single-gimbal control moment gyros systems (SCMGs) which include two types, with constant speed (CSCMG) or variable speed (VSCMG) rotors. Through angular ... This research is focused on the singularity analysis for single-gimbal control moment gyros systems (SCMGs) which include two types, with constant speed (CSCMG) or variable speed (VSCMG) rotors. Through angular momentum hypersurfaces of singular states, the passable and impassable singular points are discriminated easily, meanwhile the information about how much the angular momentum workspace as well as the steering capability available is provided directly. It is obvious that the null motions of steering laws are more effective for the five pyramid configuration(FPC) than for the pyramid configuration(PC) from the singular plots. The possible degenerate hyperbolic singular points of the preceding configurations are calculated and the distinctness of them is denoted by the Gaussian curvature. Furthermore, failure problems to steer integrated power and attitude control system (IPACS) are also analyzed. A sufficient condition of choosing configurations of VSCMGs to guarantee the IPACS steering is given. The angular momentum envelops of VSCMGs, in a given energy and a limited range of rotor speeds, are plotted. The connection and distinctness between CSCMGs and VSCMGs are obtained from the point of view of envelops. 展开更多
关键词 attitude control single-gimbal control moment gyros SINGULARITY geometric analysis angular momentum hypersurfaces store energy
在线阅读 下载PDF
The Global Positioning System (GPS): Creating Satellite Beacons in Space, Engineers Transformed Daily Life on Earth 被引量:6
3
作者 Peter Weiss 《Engineering》 SCIE EI 2021年第3期290-303,共14页
1.Prologue In late 1990,war in the Persian Gulf loomed beyond a January deadline for lraq to pull its invading forces back from Kuwait.On the front lines of the buildup leading to Operation Desert Storm,American troop... 1.Prologue In late 1990,war in the Persian Gulf loomed beyond a January deadline for lraq to pull its invading forces back from Kuwait.On the front lines of the buildup leading to Operation Desert Storm,American troops began asking their families back home to shop local marine supply stores for commercial satellite navigation receivers and to mail the devices to them in the Middle East.A groundbreaking satellite constellation that the US military had been developing for decades to provide the nation's troops with global navigation data still lacked about a third of its full count of spacecraft. 展开更多
关键词 STORES EARTH BREAKING
在线阅读 下载PDF
Big Data Analytics in Healthcare——A Systematic Literature Review and Roadmap for Practical Implementation 被引量:2
4
作者 Sohail Imran Tariq Mahmood +1 位作者 Ahsan Morshed Timos Sellis 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第1期1-22,共22页
The advent of healthcare information management systems(HIMSs)continues to produce large volumes of healthcare data for patient care and compliance and regulatory requirements at a global scale.Analysis of this big da... The advent of healthcare information management systems(HIMSs)continues to produce large volumes of healthcare data for patient care and compliance and regulatory requirements at a global scale.Analysis of this big data allows for boundless potential outcomes for discovering knowledge.Big data analytics(BDA)in healthcare can,for instance,help determine causes of diseases,generate effective diagnoses,enhance Qo S guarantees by increasing efficiency of the healthcare delivery and effectiveness and viability of treatments,generate accurate predictions of readmissions,enhance clinical care,and pinpoint opportunities for cost savings.However,BDA implementations in any domain are generally complicated and resource-intensive with a high failure rate and no roadmap or success strategies to guide the practitioners.In this paper,we present a comprehensive roadmap to derive insights from BDA in the healthcare(patient care)domain,based on the results of a systematic literature review.We initially determine big data characteristics for healthcare and then review BDA applications to healthcare in academic research focusing particularly on No SQL databases.We also identify the limitations and challenges of these applications and justify the potential of No SQL databases to address these challenges and further enhance BDA healthcare research.We then propose and describe a state-of-the-art BDA architecture called Med-BDA for healthcare domain which solves all current BDA challenges and is based on the latest zeta big data paradigm.We also present success strategies to ensure the working of Med-BDA along with outlining the major benefits of BDA applications to healthcare.Finally,we compare our work with other related literature reviews across twelve hallmark features to justify the novelty and importance of our work.The aforementioned contributions of our work are collectively unique and clearly present a roadmap for clinical administrators,practitioners and professionals to successfully implement BDA initiatives in their organizations. 展开更多
关键词 Big data analytics(BDA) big data architecture healthcare NoSQL data stores patient care ROADMAP systematic literature review
在线阅读 下载PDF
A Hierarchy of Axiom Systems for Set Theory
5
作者 张锦文 《Chinese Quarterly Journal of Mathematics》 CSCD 1989年第3期7+1-6,共7页
在文献[1,2]中,我们研究了范畴论基础,建立了集合的公理系统ACG,它能够处理超出了集合与类的极其大的汇合。本文进一步推广了系统ACG,建立了集合论公理系统的三个无穷序列:H<sub>0</sub>,H<sub>1</sub>,…;J<... 在文献[1,2]中,我们研究了范畴论基础,建立了集合的公理系统ACG,它能够处理超出了集合与类的极其大的汇合。本文进一步推广了系统ACG,建立了集合论公理系统的三个无穷序列:H<sub>0</sub>,H<sub>1</sub>,…;J<sub>0</sub>,J<sub>1</sub>,…,G<sub>0</sub>,G<sub>1</sub>,…。在建立这些公理系统的过程中,我们使用了类型论的方法,它们描述的能力是逐步增长的, 展开更多
关键词 集合论公理系统 AXIOM 类型论 范畴论 无穷序列 Numbers 数学季刊 stored INFINITY proof
在线阅读 下载PDF
Sorption Characteristics of CO<sub>2</sub>on Rocks and Minerals in Storing CO<sub>2</sub>Processes 被引量:2
6
作者 Takashi Fujii Satomi Nakagawa +2 位作者 Yoshiyuki Sato Hiroshi Inomata Toshiyuki Hashida 《Natural Resources》 2010年第1期1-10,共10页
As CO2 is injected into pore spaces of water-filled reservoir rocks, it displaces much of the pore fluids. In short terms (several to tens of years), the greater part of the injected CO2 is predicted to stay as free C... As CO2 is injected into pore spaces of water-filled reservoir rocks, it displaces much of the pore fluids. In short terms (several to tens of years), the greater part of the injected CO2 is predicted to stay as free CO2 , i.e. in a CO2 rich dense phase that may contain some water. This paper investigates the sorption characteristics for rocks (quartzose arenite, greywacke, shale, granite and serpentine) and minerals (quartz and albite) in the CO2 rich dense phase. The measurements were conducted at 50°C and 100°C, and pressures up to 20 MPa. Our results demonstrated that significant quantities of CO2 were sorbed with all the samples. Particularly, at 50°C and 100°C, quartzose arenite showed largest sorption capacity among the other samples in higher pressures (>10 MPa). Furthermore, comparison with model prediction based on the pore filling model, which assumed that CO2 acts as filling pore spaces of the rocks and minerals, suggested the importance of the sorption mechanism in the CO2 geological storage in addition to the pore-filling mechanism. The present results should be pointed out that the sorption characteristics may have significant and meaningful effect on the assessment of CO2 storage capacity in geological media. 展开更多
关键词 Sorption Characteristics Rocks MINERALS storing CO2 PROCESSES CO2 Geological Storage
暂未订购
Research on Solar Cell with Storing Solar Energy Film
7
作者 李宝骏 赵阳春 +3 位作者 杨淘 祝金兰 高飞 付希亮 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期228-230,共3页
Solar cell is an effective apparatus which can transform solar energy into electrical energy. However, the main problem is the low density and discontinuity of solar energy at present. The solar cell with a layer of r... Solar cell is an effective apparatus which can transform solar energy into electrical energy. However, the main problem is the low density and discontinuity of solar energy at present. The solar cell with a layer of rare earth film can absorb incidence sunlight and enhance the energy density of solar energy. The rare earth film can absorb solar energy and bear high temperature of 300~450 ℃. Moreover, in rainy days or at night, the film radiates the solar energy it stored in 8~12 h, so that the solar cell can work continuously, which remarkably enhanced the efficiency of solar cell. 展开更多
关键词 solar energy CELL storing energy solar energy film rare earths
在线阅读 下载PDF
A DESIGN FOR THE GLOBAL KARST INFORMATION MANAGEMENT SYSTEM
8
作者 Lin Xinhong The Institute of Karst Geology, Guilin, China 《中国岩溶》 CAS CSCD 北大核心 1992年第S1期232-238,共7页
"The Global Karst Information Management System (GKIMS)" is a sub-project of International Geological Correlation Program Project 299 "Geology, Climate, Hydrology and Karst Formation". GKIMS is dev... "The Global Karst Information Management System (GKIMS)" is a sub-project of International Geological Correlation Program Project 299 "Geology, Climate, Hydrology and Karst Formation". GKIMS is developed on AST-386 microcomputer by using DBASE-Ⅲ plus, FOX-BASE, FORTRAN and BASIC as the supporting software. 展开更多
关键词 FORTRAN Correlation SUPPORTING stored KARST BASIC latter HARDWARE CONVENIENT distinguished
在线阅读 下载PDF
Construction of a sequential light-harvesting system via supramolecular copolymerization
9
作者 Hongwei Qian Tangxin Xiao +1 位作者 Robert B.P.Elmes Leyong Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第8期1-2,共2页
The current energy crisis is a worldwide problem and the search for clean and economic energy production is a global challenge.In this context,the exploitation and utilization of solar energy is becoming more and more... The current energy crisis is a worldwide problem and the search for clean and economic energy production is a global challenge.In this context,the exploitation and utilization of solar energy is becoming more and more popular.Photosynthesis in nature sets an outstanding example to harvest,transfer and store solar energy[1].In most of the photosynthetic organisms such as purple photosynthetic bacteria,the rigid protein scaffolds serve as key elements to bind pigments and control their excitation energy transfer.Sequential energy transfer is especially intriguing in this field to make full use of full-band solar energy.To mimic natural photosynthesis[2]. 展开更多
关键词 BECOMING HARVESTING STORE
原文传递
Numerical Investigation of the Thermal Behavior of a System with a Partition Wall Incorporating a Phase Change Material
10
作者 Nisrine Hanchi Hamid Hamza +2 位作者 Jawad Lahjomri Khalid Zniber Abdelaziz Oubarra 《Fluid Dynamics & Materials Processing》 EI 2023年第5期1227-1236,共10页
The work deals with the thermal behavior of a conventional partition wall incorporating a phase change material(PCM).The wall separates two environments with different thermal properties.The first one is conditioned,w... The work deals with the thermal behavior of a conventional partition wall incorporating a phase change material(PCM).The wall separates two environments with different thermal properties.The first one is conditioned,while the adjacent space is characterized by a temperature that changes sinusoidally in time.The effect of the PCM is assessed through a comparative analysis of the cases with and without PCM.The performances are evaluated in terms of dimensionless energy stored within the wall,comfort temperature and variations of these quantities as a function of the amount of PCM and its emplacement. 展开更多
关键词 Phase change materials rangemelting temperature composite wall comfort temperature dimensionless energy stored
在线阅读 下载PDF
Feasibility Study of Optimal Sizing of Micro-Cogeneration System for Convenience Stores in Bangkok
11
作者 Suapphong Kritsanawonghong Weijun Gao Pawinee Iamtrakul 《Energy and Power Engineering》 2014年第5期69-81,共13页
In this paper, the optimization of micro-cogeneration (μ-CHP) system sizing for convenience stores in Thailand is conducted under the present condition of fuel prices and tariff rates. The assessment of (μ-CHP) syst... In this paper, the optimization of micro-cogeneration (μ-CHP) system sizing for convenience stores in Thailand is conducted under the present condition of fuel prices and tariff rates. The assessment of (μ-CHP) system performance is analyzed by using Primary Energy Saving (PES) Ratio for evaluating the energy performance. Also, the Annual Cost Saving Ratio (CSR) and Payback Period (PBP) are used for evaluating the economic performance of μ-CHP system. The analysis results show the optimal size of μ-CHP system under possible conditions including the operating schedule and system’s efficiency were conducted. 展开更多
关键词 CONVENIENCE STORES MICRO-COGENERATION system Energy Efficiency ECONOMIC Assessment Thailand
暂未订购
A Design of Acoustic Signal Wireless Acquisition System for Stored Grain Pests Based on Compressed Sensing
12
作者 韩安太 杨悦梅 袁炼红 《Journal of Donghua University(English Edition)》 EI CAS 2012年第1期89-93,共5页
In order to achieve the acoustic signal distributed acquisition of stored grain pests, a novel acoustic signal acquisition system was presented based on the wireless sensor networks. And the system architecture, hardw... In order to achieve the acoustic signal distributed acquisition of stored grain pests, a novel acoustic signal acquisition system was presented based on the wireless sensor networks. And the system architecture, hardware configuration, and software were introduced in detail. Considering bandwidth limitation of wireless sensor networks, random sampling algorithm based on the compressed sensing theory was proposed. The developed acoustic signal acquisition system was applied in sampling the crawl acoustic signal of Tribolinm castaneum Herbst adults in granary. Preliminary experimentation indicated the rationality and practicability of the developed system and the proposed algorithm. They can implement the remote, real-time, and reliable wireless transmission for the acoustic signal sampled data of multiple points stored grain pests effectively. 展开更多
关键词 wireless sensor networks compressed sensing random sampling stored grain pests acoustic signal
在线阅读 下载PDF
Storing and Searching Metadata for Digital Broadcasting on Set-Top Box Environments
13
作者 Jong-Hyun Park Ji-Hoon Kang 《Journal of Software Engineering and Applications》 2008年第1期26-32,共7页
Digital broadcasting is a novel paradigm for the next generation broadcasting. Its goal is to provide not only better quality of pictures but also a variety of services that is impossible in traditional airwaves broad... Digital broadcasting is a novel paradigm for the next generation broadcasting. Its goal is to provide not only better quality of pictures but also a variety of services that is impossible in traditional airwaves broadcasting. One of the important factors for this new broadcasting environment is the interoperability among broadcasting applications since the environment is distributed. Therefore the broadcasting metadata becomes increasingly important and one of the metadata standards for a digital broadcasting is TV-Anytime metadata. TV-Anytime metadata is defined using XML schema, so its instances are XML data. In order to fulfill interoperability, a standard query language is also required and XQuery is a natural choice. There are some researches for dealing with broadcasting metadata. In our previous study, we have proposed the method for efficiently managing the broadcasting metadata in a service provider. However, the environment of a Set-Top Box for digital broadcasting is limited such as low-cost and low-setting. Therefore there are some considerations to apply general approaches for managing the metadata into the Set-Top Box. This paper proposes a method for efficiently managing the broadcasting metadata based on the Set-Top Box and a prototype of metadata management system for evaluating our method. Our system consists of a storage engine to store the metadata and an XQuery engine to search the stored metadata and uses special index for storing and searching. Our two engines are designed independently with hardware platform therefore these engines can be used in any low-cost applications to manage broadcasting metadata. 展开更多
关键词 Digital BROADCASTING METADATA Management storing and SEARCHING XML Data XQUERY Processing TV-Anytime METADATA Set-Top BOX
暂未订购
Teaching Reform and Practice in Colleges and Universities under 1 + X Certificate System -- Taking the Course "Online Store Operation and Promotion" as an Example
14
作者 TANGYi 《外文科技期刊数据库(文摘版)教育科学》 2022年第5期184-187,共4页
Under the double background of "National Vocational Education Reform Implementation Plan" and "1 + X" certificate system, the steady progress of "online shop operation and promotion" cour... Under the double background of "National Vocational Education Reform Implementation Plan" and "1 + X" certificate system, the steady progress of "online shop operation and promotion" course teaching in colleges and universities has achieved good results, especially promoting the reform of teaching content and methods, and paying more attention to the training of professional talents. This paper firstly to the "1 + X" certificate system and "store operation and promotion" course for a simple introduction, and then based on the "1 + X" certificate system, focus on the "store operation and promotion" course teaching reform objectives and content. In the teaching reform content of the "online store operation and promotion" curriculum, we should focus on four aspects: one is to systematically optimize the teaching content;the second is to innovate the teaching methods;the third is to cultivate professional teachers;the fourth is to optimize the curriculum teaching evaluation system. 展开更多
关键词 "1 + X" certificate system online store operation and promotion teaching reform
在线阅读 下载PDF
“苹果税”反竞争性研究:根源、表现及治理进路 被引量:1
15
作者 张海汝 李勇坚 蒋艳 《企业经济》 北大核心 2025年第2期59-68,共10页
应用商店作为典型的数字平台,成为应用软件分发行业的“守门人”,对应用软件开发者收取“抽成”已成为应用商店行业普遍现象。目前,以“苹果税”为代表的“抽成”行为已对应用软件行业的发展产生了不良影响,引发了世界各国的诉讼和监管... 应用商店作为典型的数字平台,成为应用软件分发行业的“守门人”,对应用软件开发者收取“抽成”已成为应用商店行业普遍现象。目前,以“苹果税”为代表的“抽成”行为已对应用软件行业的发展产生了不良影响,引发了世界各国的诉讼和监管行动。我国作为全球“苹果税”比例最高的地区,对以“苹果税”为代表的应用商店平台“抽成”行为的监管还相对滞后,制约了我国应用软件行业的健康有序发展。对此,本文针对App Store“苹果税”的形成根源与具体表现进行分析,在借鉴世界各国监管规制App Store“苹果税”行为实践经验的基础上,针对我国“苹果税”与类似“抽成”行为的现实情况,提出治理我国应用软件分发平台抽成行为的对策建议。 展开更多
关键词 App Store “苹果税” 应用商店 抽成行为
在线阅读 下载PDF
Confined proton transport in water-containing layered manganese oxide electrodes 被引量:1
16
作者 Wenwei Cai Feng Pan Shunning Li 《Chinese Journal of Structural Chemistry》 2025年第5期15-18,共4页
Understanding the proton dynamic behavior in inorganic materials has long been a topic of intense fascination[1],especially in the field of electrochemical energy storage[2].One of the examples is the research of prot... Understanding the proton dynamic behavior in inorganic materials has long been a topic of intense fascination[1],especially in the field of electrochemical energy storage[2].One of the examples is the research of proton transport in transition metal oxides,which dates back to 1971[3]when RuO_(2) was discovered to be capable of storing protons via reversible redox reactions[4].In aqueous electrolytes,the thin film RuO_(2) electrode exhibits a surface pseudocapacitive behavior[5],which could be modified by the structural water in its hydrated form due to the facile Grotthuss hopping mode of protons along the established hydrogen bonds inside the bulk phase[6].Soon later,Goodenough et al.reported the capacitor-like behavior of amorphous MnO_(2)·xH_(2)O electrode in an aqueous KCl electrolyte[7],and further studies on the hydrated MnO_(2) electrodes prepared by sol-gel processes have soon discovered that the intercalation of protons from aqueous electrolytes plays an indispensable role in the charge storage mechanism[8].In recent years,the research interest on rechargeable aqueous batteries has fueled the renaissance of mechanistic study of proton transport in transition metal oxides[9],which can operate as cathodes or anodes via a topotactic insertion mechanism similar to that in Li-ion batteries[10].However,due to the challenges for experimental detection of local chemical environments of the inserted protons,a comprehensive understanding of proton dynamic behavior in these electrodes remains largely lacking. 展开更多
关键词 transition metal oxideswhich storing protons inorganic materials thin film ruo proton transport reversible redox reactions understanding proton dynamic behavior electrochemical energy storage one
原文传递
What's on Each Floor?
17
作者 Maria Chiu 《空中英语教室(初级版.大家说英语)》 2025年第6期34-35,54,共3页
Conversation A(in a department store)Sara:Department store directories are helpful.Sam:They are.Today,I have to buy new furniture and bedding for my apartment.They're on the sixth floor.
关键词 BEDDING FURNITURE department store store directories FLOOR
原文传递
学与练
18
《初中生辅导》 2025年第4期28-34,共7页
一、单词拼写1.Light travels much faster than___(声音).2.It's______(容易的)for us to pay online with Alipay now,3.The teacher often____(测试)his students in math.4.At that time,things could be_____(困难的)for the w... 一、单词拼写1.Light travels much faster than___(声音).2.It's______(容易的)for us to pay online with Alipay now,3.The teacher often____(测试)his students in math.4.At that time,things could be_____(困难的)for the workers.5.It's said that she's__(储备)nearly one ton of potatoes at home.6.In his spare time,Dr.Yuan loves playing the piano and listening to__(音乐),especially Mozart's. 展开更多
关键词 tests MUSIC pay online STORES sound DIFFICULT EASY MOZART
原文传递
Get Around
19
《China Textile》 2025年第5期78-79,共2页
Train Mass Rapid Transit(MRT)was put into service in 1987,and has since been augmented by and linked to the Light Rapid Transit.Combined,you can often get you within walking distance of most destinations.The maps on t... Train Mass Rapid Transit(MRT)was put into service in 1987,and has since been augmented by and linked to the Light Rapid Transit.Combined,you can often get you within walking distance of most destinations.The maps on the metro system are easy to read,complete with English version.You can easily purchase an EZ-Link card or a NETS Flashpay Card(stored value cards)at all MRT stations and bus interchange. 展开更多
关键词 Nets Flashpay Card nets flashpay card stored train mass rapid transit mrt Light Rapid Transit EZ Link Card Stored Value Cards light rapid MRT
在线阅读 下载PDF
善意时刻
20
作者 Joseph J.Mazzella 《疯狂英语(新读写)》 2025年第6期34-36,76,共4页
简单的善举不仅温暖了他人,也让施助者感受到内心的充盈与喜悦,既彰显出爱的力量,更传递出分享的真谛。1 I have no idea why some stores make shelves so high that only a professional basketball player can reach them,but they d... 简单的善举不仅温暖了他人,也让施助者感受到内心的充盈与喜悦,既彰显出爱的力量,更传递出分享的真谛。1 I have no idea why some stores make shelves so high that only a professional basketball player can reach them,but they do.I experienced one of them just the other day.I had just picked up some toothpaste and deodorant and was heading to the dog food section when I took a short cut through the toy section. 展开更多
关键词 TOYS toy section STORES short cut dog food shelves
在线阅读 下载PDF
上一页 1 2 60 下一页 到第
使用帮助 返回顶部