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More tree growth reduction due to consecutive drought and its legacy effect for a semiarid larch plantation in Northwest China
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作者 Yanfang Wan Pengtao Yu +5 位作者 Yanhui Wang Jiamei Li Yushi Bai Yipeng Yu Bingbing Liu Xiaocha Wei 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期188-196,共9页
Extreme climate has increasingly led to negative impacts on forest ecosystems globally,especially in semiarid areas where forest ecosystems are more vulnerable.However,it is poorly understood how tree growth is affect... Extreme climate has increasingly led to negative impacts on forest ecosystems globally,especially in semiarid areas where forest ecosystems are more vulnerable.However,it is poorly understood how tree growth is affected by different drought events.In 2006–2009,the larch plantations in the semiarid areas of Northwest China were negatively affected by four consecutive dry years,which was a very rare phenomenon that may occur frequently under future climate warming.In this study,we analyzed the effect of these consecutive dry years on tree growth based on the data of the tree rings in the dominant layer of the forest canopy on a larch plantation.We found that the tree-ring width index(RWI)in dry years was lower than that in normal years,and it experienced a rapidly decreasing trend from 2006 to 2009(slope=-0.139 year^(-1),r=-0.94)due to water supply deficits in those dry years.Drought induced legacy effects of tree growth reduction,and consecutive dry years corresponded with greater growth reductions and legacy effects.Growth reductions and legacy effects were significantly stronger in the third and fourth consecutive dry years than that of single dry year(p<0.05),which might have been due to the cumulative stress caused by consecutive dry years.Our results showed that larch trees experienced greater tree growth reduction due to consecutive dry years and their legacy effect,and the trees had lower recovery rates after consecutive dry years.Our results highlight that consecutive dry years pose a new threat to plantations under climate warming,and thus,the effect of climate extremes on tree growth should be considered in growth models in semiarid areas. 展开更多
关键词 Tree rings Drought effects legacy effects Growth-climate relationships Larix principis-rupprechtii
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Overstory functional groups indicate the legacy of land use in a secondary tropical forest in southwestern China
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作者 Yun Deng Wenfu Zhang +9 位作者 Min Cao Jinlong Dong Hui Chen Xiaobao Deng Jiajia Liu Xiaoyang Song Shangwen Xia Liqing Sha Shengdong Yuan Luxiang Lin 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期91-105,共15页
Anthropogenic disturbances are widespread in tropical forests and influence the species composition in the overstory.However,the impacts of historical disturbance on tropical forest overstory recovery are unclear due ... Anthropogenic disturbances are widespread in tropical forests and influence the species composition in the overstory.However,the impacts of historical disturbance on tropical forest overstory recovery are unclear due to a lack of disturbance data,and previous studies have focused on understory species.In this study,the purpose was to deter-mine the influence of historical disturbance on the diver-sity,composition and regeneration of overstory species in present forests.In the 20-ha Xishuangbanna tropical sea-sonal rainforest dynamics plot in southwestern China,the historical disturbance boundaries were delineated based on panchromatic photographs from 1965.Factors that drove species clustering in the overstory layer(DBH≥40 cm)were analyzed and the abundance,richness and composition of these species were compared among different tree groups based on multiple regression tree analysis.The coefficient of variation of the brightness value in historical panchro-matic photographs from 1965 was the primary driver of spe-cies clustering in the overstory layer.The abundance and richness of overstory species throughout the regeneration process were similar,but species composition was always different.Although the proportion of large-seeded and vigorous-sprouting species showed no significant differ-ence between disturbed and undisturbed forests in the tree-let layer(DBH<20 cm),the difference became significant when DBH increased.The findings highlight that historical disturbances have strong legacy effects on functional group composition in the overstory and the recovery of overstory species was multidimensional.Functional group composi-tion can better indicate the dynamics of overstory species replacement during secondary succession. 展开更多
关键词 Historical disturbance legacy effects Secondary forests Overstory species Functional groups
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The legacy effects of rubber defoliation period on the refoliation phenology,leaf disease,and latex yield 被引量:1
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作者 De-Li Zhai Jian-Chu Xu 《Plant Diversity》 SCIE CAS CSCD 2023年第1期98-103,共6页
The leaf phenology of trees has received particular attention for its crucial role in the global water and carbon balances,ecosystem,and species distribution.However,current studies on leaf phenology have mainly focus... The leaf phenology of trees has received particular attention for its crucial role in the global water and carbon balances,ecosystem,and species distribution.However,current studies on leaf phenology have mainly focused on temperate trees,while few studies including tropical trees.Little attention has been paid to globally extensive industrial plantations.Rubber plantations are important to both the local and global economies.In this study,we investigated the legacy effects of defoliation phenology on the following year’s leaf flushing,leaf disease,and also latex yield of rubber trees,an economically important tree to local people and the world.Results show that extended duration of defoliation increased the subsequent duration of refoliation and rates of infection by powdery mildew disease,but led to reduced latex yield in March.This legacy effect of rubber defoliation may relate to the carbohydrate reserved in the trees.A longer duration of defoliation would consume more reserved carbohydrates,reducing available reserves for disease defense and latex production.Extended duration of defoliation period was associated with either a lower temperature before the cessation of latex tapping in October-November and/or a higher temperature after the cessation of latex tapping in December-January.Leaf falling signals the end of photosynthetic activities in deciduous trees.Thus,the leaf falling phenology will impact ecological processes involving rubber trees.Our findings indicated that the inclusion of defoliation periods in future rubber trees’ research,will be crucial to furthering our understanding of leaf flushing,powdery mildew disease,and latex yield. 展开更多
关键词 CARBOHYDRATE DEFOLIATION legacy effect PHENOLOGY Rubber trees
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敏捷供应链中基于多代理的Legacy系统封装技术 被引量:8
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作者 刘敏 李彪 张申生 《上海交通大学学报》 EI CAS CSCD 北大核心 2001年第2期197-200,共4页
为解决敏捷供应链中各异构 Legacy系统的封装、集成问题 ,分析了直接数据库存取、基于函数与过程的调用、基于多代理封装等 3种 Legacy系统封装方案 ,采用 CORBA、智能代理技术构造了基于多代理的 Legacy系统封装框架 ,以实现系统的功... 为解决敏捷供应链中各异构 Legacy系统的封装、集成问题 ,分析了直接数据库存取、基于函数与过程的调用、基于多代理封装等 3种 Legacy系统封装方案 ,采用 CORBA、智能代理技术构造了基于多代理的 Legacy系统封装框架 ,以实现系统的功能与信息集成 .在 Windows环境下实现了构成内封装适配器的网络通信代理、服务分解代理与监控执行代理等 3个智能代理 . 展开更多
关键词 敏捷供应链 代理 legacy系统 封装
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Legacy系统封装技术及其在供应链管理中的应用 被引量:4
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作者 刘建勋 张申生 《计算机工程》 CAS CSCD 北大核心 2002年第5期46-48,共3页
介绍了系统的封装方法,通过一个实例介绍了其在供应链中的具体应用。该实例亦说明通过对封装来实现系统集成是LegacyLegacy有效和可行的。
关键词 软件系统 企业 legacy系统 封装技术 供应链管理
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正确设置EFIBIOS与Legacy BIOS安装Windows系统 被引量:4
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作者 余立强 《教育教学论坛》 2015年第3期175-177,共3页
本文阐述了计算机主板中的EFI BIOS与Legacy BIOS的基本概念,使用命令操作,解决GPT磁盘与MBR磁盘格式间的转换问题,比较全面地描述了用U盘引导安装Windows系统中的系统分区方案,具有很好的实际操作性和指导作用。
关键词 EFI BIOS legacy BIOS U盘引导 分区方案 安装Windows
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NonStop CORBA应用与legacy系统的集成技术
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作者 寿建霞 郭永艳 《浙江工业大学学报》 CAS 2004年第3期290-295,共6页
在利用NonStopCORBA技术开发大型企业级应用系统时,必然要将许多非CORBA的client/server(即legacy系统)集成到CORBA应用系统中来,为了不重写legacy系统代码,必须采用一种包装技术。详细阐述了可实现legacy系统与CORBA应用集成的legacy... 在利用NonStopCORBA技术开发大型企业级应用系统时,必然要将许多非CORBA的client/server(即legacy系统)集成到CORBA应用系统中来,为了不重写legacy系统代码,必须采用一种包装技术。详细阐述了可实现legacy系统与CORBA应用集成的legacy包装技术。采用该技术创建的legacywrapper是一个CORBA程序,它通过对legacy系统进行封装,从而使得legacy系统可集成到CORBA应用中。以C++pathsendclientwrapper为例,分析了legacyclientwrapper的创建步骤,给出了详细的编程细节。该技术已应用于多个NonStopCORBA应用系统中。 展开更多
关键词 NONSTOP CORBA legacy系统 集成 WRAPPER 事件框架
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Obama's Legacy The Foreign Policy of the Late-Term Obama Administration
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作者 Ni Feng 《Contemporary International Relations》 2017年第2期67-81,共15页
The year 2014 was a tipping point for the Barack Obama Administration--that was the year when it strove to forge a legacy of the Obarna era but came up against challenges arising from major changes that were taking pl... The year 2014 was a tipping point for the Barack Obama Administration--that was the year when it strove to forge a legacy of the Obarna era but came up against challenges arising from major changes that were taking place internationally and domestically. The Administration was then focused on maintaining a fragile balance between creating this legacy and responding to these challenges. Obama stuck to his fundamental principles when dealing with overseas affairs, but he also came up with new responses. The dynamic balance struck between these two formed the basis of the global strategy of the late-term Obama Administration. The Administration's focus at this time highlights the dilemma it faced in forging a legacy. Further, the foreign policy of Obama and Trump are actually not so different; they both supported some degree of isolationism with a focus on domestic issues. 展开更多
关键词 US global strategy Obama's legacy diplomatic legacy
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Health, Physical Activity and the Rio de Janeiro 2016 Olympic Games: Legacy or Fallacy? 被引量:4
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作者 Vagner Rosa Bizarro Tatiane Andreazza Lucchese +7 位作者 Amanda Maia Breis Karine Rucker Minelli Salles Alves Fernandes Mikele Torino Paletti Ana Luísa Conceição de Jesus Raphael Calafange Marques Pereira Denise Rosso Tenório Wanderley Rocha Alberto Krayyem Arbex 《Health》 CAS 2016年第1期9-17,共9页
It is generally expected that the Rio de Janeiro 2016 Olympic and Paralympic Games will bring health and social benefits to their host city and to Brazil. This assumption comes from “common sense”, as a logical conc... It is generally expected that the Rio de Janeiro 2016 Olympic and Paralympic Games will bring health and social benefits to their host city and to Brazil. This assumption comes from “common sense”, as a logical conclusion arising from the fact that host cities “inspire” and stimulate lifestyle changes. Benefits are also expected on tourism, self-image, architecture and the economy of the country as a whole. But are these expectations real and evidence-based? What parts of these “facts” are concrete and which ones are not? This paper suggests available ways of quantifying positive effects of hosting an Olympic Game, and puts the focus of this approach on the Rio de Janeiro 2016 Olympic Games and their true legacy, seeking scientific certainties. 展开更多
关键词 Physical Activity Olympic Games Paralympic Games Olympic legacy Rio de Janeiro Rio 2016
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A Component Mining Approach to Incubate Grid Services in Object-Oriented Legacy Systems 被引量:2
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作者 Jian-Zhi Li Zhuo-Peng Zhang Bing Qiao Hong-Ji Yang 《International Journal of Automation and computing》 EI 2006年第1期47-55,共9页
This paper describes an approach for Grid service component mining in object-oriented legacy systems, applying software clustering, architecture recovery, program slicing and wrapping techniques to decompose a legacy ... This paper describes an approach for Grid service component mining in object-oriented legacy systems, applying software clustering, architecture recovery, program slicing and wrapping techniques to decompose a legacy system, analyse the concerned components and integrate them into a Grid environment. The resulting components with core legacy code function in a Grid service framework. 展开更多
关键词 Grid service legacy system software component software clustering architecture recovery program slicing.
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Soil polygon disaggregation through similarity-based prediction with legacy pedons 被引量:5
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作者 LIU Feng GENG Xiaoyuan +3 位作者 ZHU A-xing Walter FRASER SONG Xiaodong ZHANG Ganlin 《Journal of Arid Land》 SCIE CSCD 2016年第5期760-772,共13页
Conventional soil maps generally contain one or more soil types within a single soil polygon.But their geographic locations within the polygon are not specified.This restricts current applications of the maps in site-... Conventional soil maps generally contain one or more soil types within a single soil polygon.But their geographic locations within the polygon are not specified.This restricts current applications of the maps in site-specific agricultural management and environmental modelling.We examined the utility of legacy pedon data for disaggregating soil polygons and the effectiveness of similarity-based prediction for making use of the under-or over-sampled legacy pedon data for the disaggregation.The method consisted of three steps.First,environmental similarities between the pedon sites and each location were computed based on soil formative environmental factors.Second,according to soil types of the pedon sites,the similarities were aggregated to derive similarity distribution for each soil type.Third,a hardening process was performed on the maps to allocate candidate soil types within the polygons.The study was conducted at the soil subgroup level in a semi-arid area situated in Manitoba,Canada.Based on 186 independent pedon sites,the evaluation of the disaggregated map of soil subgroups showed an overall accuracy of 67% and a Kappa statistic of 0.62.The map represented a better spatial pattern of soil subgroups in both detail and accuracy compared to a dominant soil subgroup map,which was commonly used in practice.Incorrect predictions mainly occurred in the agricultural plain area and the soil subgroups that are very similar in taxonomy,indicating that new environmental covariates need to be developed.We concluded that the combination of legacy pedon data with similarity-based prediction is an effective solution for soil polygon disaggregation. 展开更多
关键词 legacy pedon data similarity-based prediction spatial disaggregation conventional soil maps
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A Service Composition Approach Based on Sequence Mining for Migrating E-learning Legacy System to SOA 被引量:1
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作者 Zhuo Zhang Dong-Dai Zhou +1 位作者 Hong-Ji Yang Shao-Chun Zhong 《International Journal of Automation and computing》 EI 2010年第4期584-595,共12页
With the fast development of business logic and information technology, today's best solutions are tomorrow's legacy systems. In China, the situation in the education domain follows the same path. Currently, there e... With the fast development of business logic and information technology, today's best solutions are tomorrow's legacy systems. In China, the situation in the education domain follows the same path. Currently, there exists a number of e-learning legacy assets with accumulated practical business experience, such as program resource, usage behaviour data resource, and so on. In order to use these legacy assets adequately and efficiently, we should not only utilize the explicit assets but also discover the hidden assets. The usage behaviour data resource is the set of practical operation sequences requested by all users. The hidden patterns in this data resource will provide users' practical experiences, which can benefit the service composition in service-oriented architecture (SOA) migration. Namely, these discovered patterns will be the candidate composite services (coarse-grained) in SOA systems. Although data mining techniques have been used for software engineering tasks, little is known about how they can be used for service composition of migrating an e-learning legacy system (MELS) to SOA. In this paper, we propose a service composition approach based on sequence mining techniques for MELS. Composite services found by this approach will be the complementation of business logic analysis results of MELS. The core of this approach is to develop an appropriate sequence mining algorithm for mining related data collected from an e-learning legacy system. According to the features of execution trace data on usage behaviour from this e-learning legacy system and needs of further pattern analysis, we propose a sequential mining algorithm to mine this kind of data of tile legacy system. For validation, this approach has been applied to the corresponding real data, which was collected from the e-learning legacy system; meanwhile, some investigation questionnaires were set up to collect satisfaction data. The investigation result is 90% the same with the result obtained through our approach. 展开更多
关键词 Service composition E-LEARNING sequence mining algorithm service-oriented architecture (SOA) legacy system
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Zika Virus Controversies: Epidemics as a Legacy of Mega Events?
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作者 Alberto Krayyem Arbex Vagner Rosa Bizarro +5 位作者 Mikele Torino Paletti Odirlei Joanir Brandt Ana Luísa Conceição de Jesus Ian Werner Luiggi Miguez Dantas Mirella Hansen de Almeida 《Health》 CAS 2016年第7期711-722,共12页
The current knowledge of the Zika Virus epidemic clearly lacks a comprehensive understanding of its determinants and clinical outcomes. Until recently regarded as a “simple” dengue-like infection, it nowadays turned... The current knowledge of the Zika Virus epidemic clearly lacks a comprehensive understanding of its determinants and clinical outcomes. Until recently regarded as a “simple” dengue-like infection, it nowadays turned into a real challenge to Public Health around the world. The Zika Epidemic shows a quick spread, affects unprepared health systems, and presents with severe neurological complications of newborns—a concrete threat to pregnancies. This re-emerging infectious disease is a source of deep doubts and harsh debates regarding Public Health and even bioethical issues. Several doubts still remain on how to deal with the various possible transmission ways of the disease, the surge of a generation of thousands of microcephalic newborns (and questions on how to handle them within limited health systems), and severe malformations concentrated so far in Northeastern Brazil. Finally, a debate is raised about how the “Endemic State” of Brazil, deeply merged in a health care crisis for almost 40 years now, currently confronts 3 current epidemics of the arboviruses Dengue, Chikungunya and now Zika, all associated with a lack of basic sanitation. Brazil must deal with these biological threats in the context of the Rio 2016 Olympic Games, since Chikungunya has probably been brought to Brazil during the FIFA Soccer World Cup (2014) and Zika Virus spread is associated with the Soccer Confederations Cup (2013). 展开更多
关键词 Zika Virus Epidemic MICROCEPHALY BIOETHICS Public Health Guillain-Barré Syndrome Rio 2016 CHIKUNGUNYA Dengue Olympic Games legacy Basic Sanitation
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Usng Middleware to Migrate Legacy System:A Case Study
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作者 邢大红 Liu Zongtian +1 位作者 Xu Dong Yang Xuejun 《High Technology Letters》 EI CAS 2003年第4期91-93,共3页
There has been an increasing need to migrate legacy systems to new hardware technologies and software development paradigms because the legacy systems present problems such as low effectiveness and high maintenance. I... There has been an increasing need to migrate legacy systems to new hardware technologies and software development paradigms because the legacy systems present problems such as low effectiveness and high maintenance. If organizations want to remain competitive in today’s fast changing business and technological environment, they must overcome these problems. Middleware is a valuable technology in that it provides convenient methods to construct system infrastructure, so it can be used to migrate the legacy systems. This paper gives a case study on using middleware technologies for the implementation of reengineering distributed and heterogeneous bank legacy system in Anhui branch of China Construction Bank. Using middleware to migrate legacy system has proved to be good choice in practice. 展开更多
关键词 legacy system MIDDLEWARE MIGRATE
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Using a Health Level 7 Interoperability Bus to Support Legacy Systems in the Health Domain
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作者 Rafael Andrade Aldo von Wangenheim +1 位作者 Alexandre Savaris Karine Petry 《E-Health Telecommunication Systems and Networks》 2013年第4期72-80,共9页
In order to reduce the effort in the integration and actualization of heterogeneous healthcare legacy systems that should share a common database, we propose the creation of an interoperability bus using the HL7 stand... In order to reduce the effort in the integration and actualization of heterogeneous healthcare legacy systems that should share a common database, we propose the creation of an interoperability bus using the HL7 standard—the HL7Middleware. This interoperability bus is an intermediate layer responsible for the communication between a database, health information systems and medical equipment, called HL7Server. Connected systems use the HL7 messaging semantics to store and retrieve data from the database. We validate our approach with respect to two different criteria: performance and integration costs. Benchmark tests were executed with and without the use of HL7Middleware and with different network bandwidths. These results demonstrated that the performance of the interoperability bus is higher when compared to traditional database access for larger volumes of data and when the bandwidth of the user is considerably lower than the bandwidth of the connection between HL7Server and database. The overall development and deployment cost was considered low and the reusability degree of wrapper code was considered high, thus suggesting a progressive reduction of the integration costs of additional services and subsystems of an organization. 展开更多
关键词 MIDDLEWARE Healthcare INTEROPERABILITY BUS legacy System HL7 TELEMEDICINE
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The Legacy
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作者 Bill Gaither 胡光麟 《语言教育》 1993年第10期38-40,共3页
Benjy and I were working in the yard together oneafternoon. It was during a summer between college terms, atime of uncertainty② for my son. Benjy wanted to *followin my footsteps③ as a musician, but he was *impatien... Benjy and I were working in the yard together oneafternoon. It was during a summer between college terms, atime of uncertainty② for my son. Benjy wanted to *followin my footsteps③ as a musician, but he was *impatientfor④ success. I *ached for⑤ him and wished I could 展开更多
关键词 college WANTED uncertainty MAYBE The legacy THINGS EVERYONE granted 卜名 NEVER
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Performance Comparisons of Programs in Different Programming Languages Converted from Legacy Finite Element Codes
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作者 Thiruchelvam Arudchelvam Samuel Ratnajeevan Herbert Hoole 《Journal of Electrical Engineering》 2014年第5期213-220,共8页
The FORTRAN programming language was used in early days of writing finite element field computation to write programs Much of those codes were developed in an ad hoc way. Today, modem software developers face problems... The FORTRAN programming language was used in early days of writing finite element field computation to write programs Much of those codes were developed in an ad hoc way. Today, modem software developers face problems in understanding, modifying and utilizing those codes. As modem software engineers are very concerned with object oriented design, if those codes are converted into an object oriented language, they could be redesigned and deployed in an object oriented system. Those legacy codes often need to be converted not only into an object oriented programming language such as Java but also into functional oriented languages such as C. Conversion of those legacy codes into modem languages gives many advantages. The purpose of this paper is to compare the performances of such converted legacy finite element codes originally written in FORTRAN, the relevant converted C program and Java program. Sample finite element programs written in FORTRAN are converted for purposes of comparison into modem languages such as C and Java. Performances are compared based on the execution time. In addition to that, the memory sizes of the execution file of FORTRAN and C programs are also compared. Java being interpretive there is no execution file to compare. 展开更多
关键词 Finite element method legacy software performance evaluation re-engineering.
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Mt. Longhu Scenic Area and Its Taoist Legacy
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《China Today》 2001年第9期22-24,共3页
关键词 Longhu Scenic Area and Its Taoist legacy MT
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Preserving Legacy
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作者 Christophe Alexandre 《ChinAfrica》 2019年第8期54-55,共2页
In today's interconnected world, it is clear that culture has the power to transform the societies. Its various manifestations -ranging from precious historical monuments and museums to traditional practices and f... In today's interconnected world, it is clear that culture has the power to transform the societies. Its various manifestations -ranging from precious historical monuments and museums to traditional practices and forms of contemporary art - enrich every aspect of people's daily lives in countless ways. 展开更多
关键词 PRESERVING legacy interconnected world precious HISTORICAL MONUMENTS
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力狮LEGACY2.0R
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《汽车时代》 2006年第Z1期108-111,共4页
06款LEGACY力狮享有与斯巴鲁征战WRC (世界汽车拉力锦标赛)系列赛车相同的特质和核心技术,WRC赛车在艰苦崎岖比赛环境中夺冠所配备的“秘密武器”,也同样为LEGACY力狮所拥有。驾驶这款 LEGACY力狮,不但能保证驾驶者安全,还能令驾驶者体... 06款LEGACY力狮享有与斯巴鲁征战WRC (世界汽车拉力锦标赛)系列赛车相同的特质和核心技术,WRC赛车在艰苦崎岖比赛环境中夺冠所配备的“秘密武器”,也同样为LEGACY力狮所拥有。驾驶这款 LEGACY力狮,不但能保证驾驶者安全,还能令驾驶者体验驾驭赛车的感觉,拥有更多的驾驶乐趣。 展开更多
关键词 比赛环境 斯巴鲁 legacy2.0R 性力 蒸笋 一瓣 如海
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