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Classification with Convolutional Neural Networks in MapReduce
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作者 Min Chen 《Journal of Computer and Communications》 2024年第8期174-190,共17页
Deep learning (DL) techniques, more specifically Convolutional Neural Networks (CNNs), have become increasingly popular in advancing the field of data science and have had great successes in a wide array of applicatio... Deep learning (DL) techniques, more specifically Convolutional Neural Networks (CNNs), have become increasingly popular in advancing the field of data science and have had great successes in a wide array of applications including computer vision, speech, natural language processing, etc. However, the training process of CNNs is computationally intensive and has high computational cost, especially when the dataset is huge. To overcome these obstacles, this paper takes advantage of distributed frameworks and cloud computing to develop a parallel CNN algorithm. MapReduce is a scalable and fault-tolerant data processing tool that was developed to provide significant improvements in large-scale data-intensive applications in clusters. A MapReduce-based CNN (MCNN) is developed in this work to tackle the task of image classification. In addition, the proposed MCNN adopted the idea of adding dropout layers in the networks to tackle the overfitting problem. Close examination of the implementation of MCNN as well as how the proposed algorithm accelerates learning are discussed and demonstrated through experiments. Results reveal high classification accuracy and significant improvements in speedup, scaleup and sizeup compared to the standard algorithms. 展开更多
关键词 Distributed System Image Classification CNNS MAPREDUCE OVERFITTING
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A Distributed Ant Colony Optimization Applied in Edge Detection
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作者 Min Chen 《Journal of Computer and Communications》 2024年第8期161-173,共13页
With the rise of image data and increased complexity of tasks in edge detection, conventional artificial intelligence techniques have been severely impacted. To be able to solve even greater problems of the future, le... With the rise of image data and increased complexity of tasks in edge detection, conventional artificial intelligence techniques have been severely impacted. To be able to solve even greater problems of the future, learning algorithms must maintain high speed and accuracy through economical means. Traditional edge detection approaches cannot detect edges in images in a timely manner due to memory and computational time constraints. In this work, a novel parallelized ant colony optimization technique in a distributed framework provided by the Hadoop/Map-Reduce infrastructure is proposed to improve the edge detection capabilities. Moreover, a filtering technique is applied to reduce the noisy background of images to achieve significant improvement in the accuracy of edge detection. Close examinations of the implementation of the proposed algorithm are discussed and demonstrated through experiments. Results reveal high classification accuracy and significant improvements in speedup, scaleup and sizeup compared to the standard algorithms. 展开更多
关键词 Distributed System Ant Colony Optimization Edge Detection MAPREDUCE SPEEDUP
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A Distributed Particle Filter Applied in Single Object Tracking
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作者 Di Wang Min Chen 《Journal of Computer and Communications》 2024年第8期99-109,共11页
Visual object-tracking is a fundamental task applied in many applications of computer vision. Particle filter is one of the techniques which has been widely used in object tracking. Due to the virtue of extendability ... Visual object-tracking is a fundamental task applied in many applications of computer vision. Particle filter is one of the techniques which has been widely used in object tracking. Due to the virtue of extendability and flexibility on both linear and non-linear environments, various particle filter-based trackers have been proposed in the literature. However, the conventional approach cannot handle very large videos efficiently in the current data intensive information age. In this work, a parallelized particle filter is provided in a distributed framework provided by the Hadoop/Map-Reduce infrastructure to tackle object-tracking tasks. The experiments indicate that the proposed algorithm has a better convergence and accuracy as compared to the traditional particle filter. The computational power and the scalability of the proposed particle filter in single object tracking have been enhanced as well. 展开更多
关键词 Distributed System Particle Filter Single Object Tracking
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科学研究的第五范式——以智能驱动的材料设计为例 被引量:6
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作者 Can Leng Zhuo Tang +5 位作者 Yi-Ge Zhou Zean Tian Wei-Qing Huang Jie Liu Keqin Li Kenli Li 《Engineering》 SCIE EI CAS CSCD 2023年第5期126-137,I0003,I0004,共14页
科学正在进入一个新时代——第五范式——它被认为是知识整合到不同领域的主要特征,是基于无所不在的机器学习系统的计算社区中智能驱动的工作。在此,我们通过在天河一号超级计算机系统上构建的催化材料专门设计的典型平台案例,生动地... 科学正在进入一个新时代——第五范式——它被认为是知识整合到不同领域的主要特征,是基于无所不在的机器学习系统的计算社区中智能驱动的工作。在此,我们通过在天河一号超级计算机系统上构建的催化材料专门设计的典型平台案例,生动地阐明了第五范式的本质,旨在促进第五范式在其他领域的培养。第五范式平台主要包括模型自动构建(原始数据提取)、指纹自动构建(神经网络特征选择)以及跨学科知识串联的重复迭代(“火山图”)。与分解一起进行的是对迭代中实现的体系结构的性能评估。通过讨论,第五范式的智能驱动平台可以极大地简化和改进研究中极其繁琐和具有挑战性的工作,并通过补偿机器学习中缺少样本和替代一些由于计算资源不足而导致的数值计算来实现数值计算与机器学习之间的相互反馈,从而加速探索过程。在数据驱动的学科中,跨学科专家的协同作用和对动态数据需求的急剧增长仍然是一个挑战。我们相信,对第五范式平台的一瞥可以为其在其他领域的应用铺平道路。 展开更多
关键词 机器学习 自动构建 天河一号 数据驱动 神经网络 动态数据 知识整合 科学研究
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基于LUCC的城市生态安全研究进展 被引量:36
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作者 张浩 马蔚纯 HO Hon Hing 《生态学报》 CAS CSCD 北大核心 2007年第5期2109-2117,共9页
近代工业革命以来特别是二战以后,世界范围内城市化发展迅速,受城市化驱动的土地利用/覆盖变化(Land use/cover change,LUCC)及其环境影响越来越突出,不仅对城市生态安全产生了危胁,甚至在区域和全球尺度上影响生态系统的结构与功能,成... 近代工业革命以来特别是二战以后,世界范围内城市化发展迅速,受城市化驱动的土地利用/覆盖变化(Land use/cover change,LUCC)及其环境影响越来越突出,不仅对城市生态安全产生了危胁,甚至在区域和全球尺度上影响生态系统的结构与功能,成为当今地球生态系统平衡与人类社会可持续发展的研究热点。尽管LUCC与城市生态安全态势有密切联系,然而目前研究中对土地利用变化的驱动机制较为侧重,涉及LUCC对城市生态安全影响的研究文献仍很缺乏。从城市生态安全的概念辨析入手,评述了国内外LUCC与城市生态安全响应研究的进展,将相关研究分为两个阶段:即定性和(半)定量研究阶段。指出了现有研究在理论体系与研究方法在指导实践中的不足之处,即:(1)基于LUCC城市尺度的生态安全研究的理论体系尚不成熟,目前的研究多未结合研究区域LUCC的动态特征对城市生态安全状态进行评价,因而也难以应用于指导城市生态建设实践;(2)目前的城市土地利用的生态影响实例研究中仍很缺乏采用数学模型、地理信息系统(GIS)、环境影响评价(EIA)、生态风险评价技术(ERA)及政策仿真等手段进行动态化的、多场景(Multi-Scenarios)模拟分析的综合运用,也缺乏对这些研究方法在实践中的应用的比较研究;(3)缺乏从土地利用动态监测、驱动力机制、生态响应等方面进行区域生态安全演变及调控的综合研究,现实指导意义有限。在上述工作的基础上,探讨了此研究领域未来的发展方向,即:(1)实现不同研究尺度的紧密结合;(2)多种研究方法的集成运用;(3)基于多学科知识体系的评价方法与指标体系的明细化与合理化。 展开更多
关键词 土地利用/覆盖变化(LUCC) 城市生态安全 城市化 生态调控
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制度环境、产权性质与公司慈善捐赠--来自沪深A股上市公司的经验证据 被引量:8
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作者 朱金凤 Jun Lin 《财经论丛》 CSSCI 北大核心 2015年第10期77-87,共11页
公司慈善捐赠驱动因素的研究已有很多成果,但从制度环境和产权性质角度进行研究的很少。本文以沪深A股上市公司为样本,系统考察了制度环境、产权性质对公司慈善捐赠的影响。研究证实,中国各地区制度环境差异显著影响公司慈善捐赠,制度... 公司慈善捐赠驱动因素的研究已有很多成果,但从制度环境和产权性质角度进行研究的很少。本文以沪深A股上市公司为样本,系统考察了制度环境、产权性质对公司慈善捐赠的影响。研究证实,中国各地区制度环境差异显著影响公司慈善捐赠,制度环境的改善促进了企业捐赠水平的提高,且这种正向影响在非国有控股企业表现更为明显。非国有控股企业捐赠水平高于国有控股企业,且在国有控股企业中,地方政府控股国有企业捐赠水平高于中央政府控股企业。这些结论对理解制度环境在促进企业捐赠中的作用,认识中国不同产权性质企业慈善行动的深层含义具有一定的启示意义。 展开更多
关键词 制度环境 合法性 产权性质 慈善捐赠
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Accelerating Packet Classification with Counting Bloom Filters for Virtual Open Flow Switching 被引量:4
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作者 Jinyuan Zhao Zhigang Hu +1 位作者 Bing Xiong Keqin Li 《China Communications》 SCIE CSCD 2018年第10期117-128,共12页
The growing trend of network virtualization results in a widespread adoption of virtual switches in virtualized environments. However, virtual switching is confronted with great performance challenges regarding packet... The growing trend of network virtualization results in a widespread adoption of virtual switches in virtualized environments. However, virtual switching is confronted with great performance challenges regarding packet classification especially in Open Flow-based software defined networks. This paper first takes an insight into packet classification in virtual Open Flow switching, and points out that its performance bottleneck is dominated by flow table traversals of multiple failed mask probing for each arrived packet. Then we are motivated to propose an efficient packet classification algorithm based on counting bloom filters. In particular, counting bloom filters are applied to predict the failures of flow table lookups with great possibilities, and bypass flow table traversals for failed mask probing. Finally, our proposed packet classification algorithm is evaluated with real network traffic traces by experiments. The experimental results indicate that our proposed algorithm outperforms the classical one in Open v Switch in terms of average search length, and contributes to promote virtual Open Flow switching performance. 展开更多
关键词 OpenFlow virtual switching packet classification flow table lookups counting bloom filters
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Pathogenicity of Klebsiella pneumonia(KpC4)infecting maize and mice 被引量:5
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作者 HUANG Min LIN Li +7 位作者 WU Yi-xin Honhing Ho HE Peng-fei LI Guo-zhi HE Peng-bo XIONG Guo-ru YUAN Yuan HE Yue-qiu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第7期1510-1520,共11页
Recently, a new bacterial top rot disease of maize has frequently appeared in many areas of Yunnan Province, China. The pathogen of the disease was identified as Klebsiella pneumoniae (KpC4), which is well known to ... Recently, a new bacterial top rot disease of maize has frequently appeared in many areas of Yunnan Province, China. The pathogen of the disease was identified as Klebsiella pneumoniae (KpC4), which is well known to cause pulmonary and urinary diseases in humans and animals and occasionally exists as a harmless endophyte in plants. To evaluate the viru- lence of the maize pathogen to maize and mice, we inoculated maize and mice with routine inoculation and intraperitoneal injection respectively according to Koch's postulates. The results showed that KpC4 and the clinical strain K. pneumoniae 138 (Kp138) were all highly pathogenic to maize and mice and the strain re-isolated from diseased mice also caused typical top rot symptoms on maize by artificial inoculation. It is highlighting that a seemingly dedicated human/animal pathogen could cause plant disease. This is the first report of K. pneumoniae, an opportunistic pathogen of human/animal, could infect maize and mice. The findings serve as an alert to plant, medical and veterinarian scientists regarding a potentially dangerous bacterial pathogen infecting both plants and animals/humans. The maize plants in the field could serve as a reservoir for K. pneumoniae which might infect animals and probably humans when conditions are favorable. The new findings not only are significant in the developing control strategy for the new disease in Yunnan, but also serve as a starting point for further studies on the mechanism of pathogenesis and epidemiology of K. pneumoniae. 展开更多
关键词 Klebsiella pneumoniae maize top rot disease isolation and identification pathogenicity tests white mouse
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Public priorities and consumer preferences for selected attributes of automated vehicles 被引量:1
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作者 Paulina Lustgarten Scott Le Vine 《Journal of Modern Transportation》 2018年第1期72-79,共8页
Public opinion and consumer preferences are among the various constraints on the rollout of automated cars, as they will affect the decision-making of both automotive industry actors and public-sector regulators. This... Public opinion and consumer preferences are among the various constraints on the rollout of automated cars, as they will affect the decision-making of both automotive industry actors and public-sector regulators. This study contributes to the growing body of the literature regarding this issue, through a moderate-scale survey (n = 370) that incorporated both prioritization/attitudinal questions (regarding public opinion) and a stated-prefer- ence module (to identify consumer preferences). The sur- vey protocol includes a stated-preference approach to investigate consumers' preferences for the possibility of very high rates of speed in automated cars on long-distance journeys. We found separately identifiable effects for average travel speeds (manifested as journey duration) and maximum travel speed in the stated-preference scenarios. In the 'prioritization' component of the survey, respondents ranked having the 'highest possible level of safety' as the single most important benefit that they would like auto- mated cars to deliver, ahead of benefits such as being able to performing activities while traveling or having traffic congestion reduced. This result has consequences for the car-following distances that are programmed into the control algorithms of automated cars. Documenting this finding is important, as decisions must be made in the near future by driving-algorithm designers, public-sector regu- lators, and ultimately the judiciary regarding the guidelines for acceptable automated driving-behavior instructions. 展开更多
关键词 Automated car Stated-preference LOGISTICREGRESSION
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Probiotics for Antibiotic-Associated Diarrhea: What, When, and How Long?
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作者 John R. Ferguson Karen Taylor 《International Journal of Clinical Medicine》 CAS 2022年第12期571-583,共13页
Probiotics have been formally defined as “live microorganisms that confer a health benefit on the host when administered in adequate amounts.” Although a range of applications has been explored for probiotics, their... Probiotics have been formally defined as “live microorganisms that confer a health benefit on the host when administered in adequate amounts.” Although a range of applications has been explored for probiotics, their utility in antibiotic-associated diarrhea (AAD) is both biologically plausible and supported by abundant clinical evidence. However, the strength of evidence underlying the efficacy of specific strains and formulations for AAD varies widely. This review leverages recent meta-analyses and systematic reviews to clarify some outstanding issues on the utility of probiotics for AAD, including which strains have evidence for efficacy in AAD, what doses have been demonstrated to be effective, and the optimal duration of probiotic therapy, and provides practical guidance on how to select an appropriate product. Some trends emerged in this analysis of recent meta-analyses and systematic reviews, including: 1) Certain probiotics, such as Saccharomyces boulardii and some Lactobacilli-containing products, are consistently found to be effective for the management of AAD;2) Dosing thresholds for efficacy exist that must be achieved through the administration of probiotics that reliably contain the labeled amounts of probiotic constituents;3) Most effective probiotics are initiated at the same time as antibiotic therapy and continued for between 1 and 3 weeks after the cessation of therapy. These data suggest that attention must be paid to species, dose, and duration when selecting an appropriate product for patients initiating antibiotic therapy;further considerations may include the antibiotic used and the patient’s baseline risk for AAD. 展开更多
关键词 PROBIOTICS AAD Saccharomyces boulardii LACTOBACILLI
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Residential relocation in response to light rail transit investment:case study of the Hudson–Bergen Light Rail system
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作者 Xiaobo Liu Yi Deng Scott Le Vine 《Journal of Modern Transportation》 2016年第2期139-144,共6页
It is widely acknowledged that the improved accessibility enabled by investment in public transport services can, under favorable market conditions, impact the local real estate market within the zone of influence of ... It is widely acknowledged that the improved accessibility enabled by investment in public transport services can, under favorable market conditions, impact the local real estate market within the zone of influence of the service's stations. The motivation for this study is to establish the nature of two such impacts, specifically the spatial and socio-economic patterns of residential relocations that are driven by the new light rail transit (LRT) service. Using empirical data (n = 1,023) from the Hudson-Bergen Light Rail system in New Jersey (US), we report findings regarding the impacts of the introduction of the new LRT service. We investigate two linked dimensions; the first is the distinctive socio-economic profile of LRT passengers who self-report having relocated to the new transit corridor due, at least in part, to the new transit service. The second is their proximity (following their resi- dential relocation) to the new LRT line' s stations. We present a novel analysis that accounts for endogeneity between these two dimensions of residential relocation. Of light rail passengers who engaged in a residential relocation in the 5 years prior to the survey, two-thirds (69 %) indicate that proximity to the light rail service was a 'somewhat' or 'very' important consideration. Via the multivariate analysis, we demonstrate that small household size, low income, youth (as opposed to older age), and low car ownership are each positively linked, ceteris paribus, with having engaged in a residential reloca- tion motivated by the new transit service. Finally, higher household income is found to be associated with distance (after relocation) to the nearest transit station, which is consistent with bid-rent theory. 展开更多
关键词 Light rail transit Residential relocation Transit-oriented development
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一个轻型智力发育迟缓家族中异常ATP依赖的Lon蛋白酶基因突变
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作者 Higgins J.J. Pucilowska J. +2 位作者 Lombardi R.Q. Rooney J.P. 李一明 《世界核心医学期刊文摘(神经病学分册)》 2005年第5期33-33,共1页
Background: Identifying the genetic factors that contribute to memory and lea rning is limited by the complexity of brain development and the lack of suitable human models for mild disorders of cognition. Methods: Pre... Background: Identifying the genetic factors that contribute to memory and lea rning is limited by the complexity of brain development and the lack of suitable human models for mild disorders of cognition. Methods: Previously, a disease lo cus was mapped for a mild type of nonsyndromic mental retardation (IQ between 50 and 70) to a 4.2-MB interval on chromosome 3p25-pter in a large kindred. Th e genes and transcripts within the candidate region were systematically analyzed for mutations by single-strand polymorphism analysis and DNA sequencing. Resu lts: A nonsense mutation causing a premature stop codon in a novel gene (cereblo n; CRBN) was identified that encodes for an ATP-dependent Lon protease. The pr edicted protein sequence is highly conserved across species, and it belongs to a family of proteins that selectively degrade short-lived polypeptides and regu late mitochondrial replication and transcription. One member of the Lon-contai ning protein family is regionally expressed in the human hippocampus, an importa nt neuroanatomic region that is involved in long-term potentiation and learnin g. The mutation in the CRBN gene described interrupts an N-myristoylation site and eliminates a casein kinase II phosphorylation site at the C terminus. Concl usions: A gene on chromosome 3p that is associated with mild mental retardation in a large kindred is reported. This finding implicates a role for the ATP-dep endent degradation of proteins in memory and learning. 展开更多
关键词 智力发育迟缓 ATP Lon 基因突变 认知障碍 线粒体复制 蛋白谱 无义突变 终止密码子 长时程增强
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In search of America's old covered bridges
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作者 Ronald G.Knapp 《Built Heritage》 CSCD 2021年第2期16-38,共23页
America's first documented wooden covered bridge was erected at Philadelphia,Pennsylvania in 1805.Hundreds were constructed within two decades and at least 10,000 by the later 1800s.As settlers moved West,broad ri... America's first documented wooden covered bridge was erected at Philadelphia,Pennsylvania in 1805.Hundreds were constructed within two decades and at least 10,000 by the later 1800s.As settlers moved West,broad rivers were crossed with inventive structures incorporating timber trusses ingeniously developed by carpenters.Called covered bridges because of the roof and siding needed to protect the timber trusses,they became ubiquitous features on the American landscape.Over the past two centuries,most covered bridges were lost to flood,ice,arson,lightening,decay,as well as"progress,"replaced by"modern"iron,concrete,and steel spans.Of some 700 covered bridges remaining,many are mere replicas of their original forms no longer supported by timber trusses.Genuine historic bridges remain largely from the last half of the 1800s while civic boosterism has led to claims of earlier dates with often questionable authenticity.This essay presents three wooden covered bridges constructed in the 1820s along a 10-mile stretch of the Wallkill River in New Paltz,New York.Of the three,only Perrine's Bridge,constructed first in 1821 and covered in 1822,is still standing with intact Burr timber trusses.Perrine's is an iconic structure with exceptional heritage value because of authentic re-building and restoration in 1834,1846,1917,and 1968.Using documentary records,this essay establishes an accurate intertwined chronology for the three bridges,detailing nineteenth century building practices and contentious mid-twentieth century struggles pitting preservationists wanting authentic restoration against those wanting removal. 展开更多
关键词 Covered Bridge Timber truss Burr truss Town lattice truss Perrine's Bridge New Palt Bridge Phillies Bridge New York State New Paltz Conservation Restoration
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An Integrated Cyber-Physical Simulation Environment for Smart Grid Applications 被引量:14
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作者 Yuxin Wan Junwei Cao +4 位作者 Shuqing Zhang Guoyu Tu Chao Lu Xingtao Xu Keqin Li 《Tsinghua Science and Technology》 SCIE EI CAS 2014年第2期133-143,共11页
The concept of Cyber-Physical Systems (CPSs), which combine computation, networking, and physical processes, is considered to be beneficial to smart grid applications. This study presents an integrated simulation en... The concept of Cyber-Physical Systems (CPSs), which combine computation, networking, and physical processes, is considered to be beneficial to smart grid applications. This study presents an integrated simulation environment to provide a unified platform for the investigation of smart grid applications involving power grid monitoring, communication, and control. In contrast to the existing approaches, this environment allows the network simulator to operate independently, importing its results to the power system simulation. This resolves conflicts between discrete event simulation and continuous simulation. In addition, several data compensation methods are proposed and investigated under different network delay conditions. A case study of wide-area monitoring and control is provided, and the efficiency of the proposed simulation framework has been evaluated based on the experimental results. 展开更多
关键词 CONTROL cyber-physical system SIMULATION smart grid wide-area monitoring
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China’s corridor bridges:heritage buildings over water 被引量:1
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作者 Ronald G.Knapp Terry E.Miller Jie Liu 《Built Heritage》 CSCD 2020年第2期21-39,共19页
Essentially unknown in the rest of the world and only recently appreciated in China,the globally significant 3000+‘corridor bridges’(langqiao)in China far outnumber the better-known‘covered bridges’found in North ... Essentially unknown in the rest of the world and only recently appreciated in China,the globally significant 3000+‘corridor bridges’(langqiao)in China far outnumber the better-known‘covered bridges’found in North America and Europe.Rivaling or exceeding those in the West in number,age,complexity,and architectural ambition,some of China’s outstanding timber langqiao in the mountains of Fujian and Zhejiang provinces are on the cusp of being inscribed as UNESCO World Heritage cultural sites.Throughout south and central China today there is moreover a resurgence of new timber langqiao being erected using traditional carpentry alongside the unprecedented construction of modern marvels of steel and concrete.Archaeological evidence in 2001 uncovered China’s earliest‘corridor bridge’—thus the oldest known covered bridge in the world—with a length of 42m dating to the Han dynasty 2000 years ago.The Rulong Bridge,which dates to 1625 and is documented as the oldest standing woven arch-beam langqiao,can be visited today in Qingyuan county,southern Zhejiang.Even older langqiao with parallel log beams as the substructure have come to light in neighboring Fujian province,most notably the Zhiqing Bridge in a rural area of Jian’ou city that dates to 1490.China’s bridges,whether with a corridor atop or without,have traditionally not been included under the umbrella of‘vernacular architecture’even as they usually were created by local craftspeople employing the same approaches and practices for dwellings and temples.Just as with these better researched structures,langqiao must be studied not only from the perspective of architecture,but also anthropology,geography,history,and sociology,among other disciplines.Rather than being abandoned as artifacts from the past,China’s langqiao today represent a living tradition that continues serving rural communities as places of passage,spaces for leisure and marketing,sites for worship,and increasingly destinations for tourists in search of nostalgic connections with China’s past.The research presented in this article draws heavily from the authors’China’s Covered Bridges:Architecture over Water,a comprehensive book published in late 2019 in Shanghai and London by Shanghai Jiao Tong University Press that will be distributed in 2020 by the University of Hawai’i Press.Despite the scope of this book,the complexity of China’s langqiao remains understudied. 展开更多
关键词 Corridor bridges Covered bridges Heritage tourism Langqiao Rural tourism Vernacular architecture
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The genus Pythium in Taiwan,China(1)-a synoptic review
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作者 Hon-Hing HO 《Frontiers in Biology》 CSCD 2009年第1期15-28,共14页
The genus Pythium,with slightly over 280 described species,has been classified traditionally with other filamentous,coenocytic,sporangia-producing fungi as“Phycomyetes”.However,with recent advances in chemical,ultra... The genus Pythium,with slightly over 280 described species,has been classified traditionally with other filamentous,coenocytic,sporangia-producing fungi as“Phycomyetes”.However,with recent advances in chemical,ultrastructural and molecular studies,Pythium spp.are now considered as“fungus-like organisms”or“pseudo-fungi”and are placed in the Kingdom Chromista or Kingdom Straminopila,distinct from the true fungi of the Kingdom Fungi or Kingdom Mycota.They are widely distributed throughout the world as soil saprophytes or plant pathogens.Because of the warm moist maritime climate,Taiwan,China,is especially rich in Pythium species.To date,48 species of Pythium have been reported from Taiwan,China,with the dominant species being Py.vexans,Py.spinosum,Py.splendens,Py.aphanidermatum,Py.dissotocum and Py.acanthicum.There is no definite geographical distribution of Pythium spp.in Taiwan,China.Twenty nine species of Pythium have proven to be plant pathogens attacking a wide variety of woody and herbaceous plants primarily causing pre-and post-emergence seedling damping-off,root rot,stem rot and rotting of fruits,tubers and ginger rhizomes,resulting in serious economic losses.The most important plant pathogenic species include Py.aphanidermatum and Py.Myriotylum,which are most active during the hot and wet summer months;whereas Py.splendens,Py.spinosum,Py.ultimum and Py.irregulare cause the greatest damage in the cool winter.Most Pythium spp.are non-specific pathogens,infecting mainly juvenile or succulent tissues.This review attempts to assess the taxonomic position of the genus Pythium and provide details of the historical development of the study of Pythium as pathogens in Taiwan,China,causing diseases of sugarcane,trees,vegetables,fruits,specialty crops and flowering plants,as well as measures to control these diseases.Of special note is the introduction of the S-H mixture which,when used as soil amendment,effectively controls many soil-borne Pythium diseases during the early stages of plant growth.The diversity of Pythium species in Taiwan,China,is discussed in comparison with the situation in the mainland of China and suggestions are made to fully utilize Pythium spp.as agents for biological control,in industry and medicine. 展开更多
关键词 Pythiaceae OOMYCETES CHROMISTA Straminolia plant pathogens soil-borne disease saprophytes MYCOPARASITES biodiversity
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On eco-planning for an eco-demonstration park (EDP) and sustainability-Case study of the Luhua EDP in the Chongming Island of Shanghai,China
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作者 Xiangrong WANG Yi YONG +5 位作者 Shixiong WANG Hao ZHANG Hing Hon HO Pingjian WANG Shoubing WANG Weizhen CHEN 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2008年第2期178-186,共9页
Thebackground,concept,connotation,principles,andmethodsofeco-planningforanEco-Demonstration Park(EDP)and sustainability were examined based on a case study of the Luhua EDP in the Chongming Island of Shanghai,China,wh... Thebackground,concept,connotation,principles,andmethodsofeco-planningforanEco-Demonstration Park(EDP)and sustainability were examined based on a case study of the Luhua EDP in the Chongming Island of Shanghai,China,which is an important part of Shanghai Eco-city planning and construction in the 21st century.By analyzing natural,social and economic conditions,calculating population using the land capacity eco-model,eco-function zoning,and eco-construction,an innovative eco-industrial structure and technical chain were formulated.A comprehensive eco-planning scheme for the EDP was proposed,including planning and management strategies for subsystems of efficient industry,good quality human settlement,high standard eco-construction and eco-tourism as well as effective environmental protection and attractive landscape.The EDP should be an area with coordinated and sustainable economic,social and environmental subsystems.Eco-planning for the EDP should be a very important part of eco-city planning and sustainability.The paper aims to set up a theoretical framework and practical basis for eco-planning and promoting harmony between human and nature. 展开更多
关键词 eco-demonstration park(EDP) eco-planning eco-model Luhua Chongming Island SHANGHAI
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Energy-aware scheduling with reconstruction and frequency equalization on heterogeneous systems
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作者 Yong-xing LIU Ken-li LI +1 位作者 Zhuo TANG Ke-qin LI 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2015年第7期519-531,共13页
With the increasing energy consumption of computing systems and the growing advocacy for green computing, energy efficiency has become one of the critical challenges in high-performance heterogeneous computing systems... With the increasing energy consumption of computing systems and the growing advocacy for green computing, energy efficiency has become one of the critical challenges in high-performance heterogeneous computing systems. Energy consumption can be reduced by not only hardware design but also software design. In this paper, we propose an energy-aware scheduling algorithm with equalized frequency, called EASEF, for parallel applications on heterogeneous computing systems. The EASEF approach aims to minimize the finish time and overall energy consumption. First, EASEF extracts the set of paths from an application. Then, it reconstructs the application based on the extracted set of paths to achieve a reasonable schedule. Finally, it adopts a progressive way to equalize the frequency of tasks to reduce the total energy consumption of systems. Randomly generated applications and two real-world applications are examined in our experiments. Experimental results show that the EASEF algorithm outperforms two existing algorithms in terms of makespan and energy consumption. 展开更多
关键词 Directed acyclic graph Dynamic voltage scaling Energy aware Heterogeneous systems Taskscheduling
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China’s structural transformation:reaching potential GDP in the financial services sector
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作者 Sara Hsu Alba Carolina Melchor Simon 《China Finance and Economic Review》 2016年第2期37-57,共21页
China’s economy faces the daunting challenge of shifting from a manufacturing-based economy to a services-based economy.Reforms in the services sector are slated to continue to take place in the coming years,includin... China’s economy faces the daunting challenge of shifting from a manufacturing-based economy to a services-based economy.Reforms in the services sector are slated to continue to take place in the coming years,including in the financial sector.In this paper,we explore China’s success and challenges with structural change,then take a closer look at the financial services sector to find out where reforms have occurred,where the potential lies,and what the future will bring.We first describe structural change with regard to growth and TFP,then as it applies to China.We examine China’s financial services sector.Next,we calculate potential GDP of the financial services sector now and with the implementation of expected reforms.We find that,given even conservative estimates,the value added of the financial intermediation sector could double,as labor,capital,technology,and elasticity respond to liberalization policies.Whether potential GDP under reforms is reached is another question;therefore,we recommend that China both increase the pace of implementation,focusing in particular on reducing the oligopoly in the banking sector,increasing investment options by reforming its bond and equity markets,and enhancing innovation in the financial sphere while controlling for risk. 展开更多
关键词 China financial sector structural transformation BANKING
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