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Can environmental sustainability be decoupled from economic growth? Empirical evidence from Eastern Europe using the common correlated effect mean group test 被引量:1
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作者 Kwaku ADDAI Berna SERENER Dervis KIRIKKALELI 《Regional Sustainability》 2023年第1期68-80,共13页
The European Union(EU) and Organisation for Economic Co-operation and Development(OECD) aim to develop long-term policies for their respective member countries. Having observed increasing dangers to the environment po... The European Union(EU) and Organisation for Economic Co-operation and Development(OECD) aim to develop long-term policies for their respective member countries. Having observed increasing dangers to the environment posed by rising economic growth, they are seeking pathways to enable policy action on economic growth and environmental sustainability. Given the facts in theoretical and empirical studies, this study assessed the validity of the decoupling hypothesis by investigating asymmetricity in the relationship between environmental sustainability and economic growth in nine Eastern European countries from 1998 to 2017 using the cross-section augmented Dickey-Fuller(CADF) unit root, panel corrected standard error(PCSE), common correlated effect mean group(CCEMG), and Dumitrescu Hurlin causality approaches. Both population growth and drinking water are used as controlled variables. The outcomes establish strong cointegration among all the variables of interest. According to the results of CCEMG test, economic growth exerts short-term environmental degradation but has long-term environmental benefits in Eastern Europe;and population growth and drinking water exert a positive effect on environmental sustainability in both the short-and long-run. The results of Dumitrescu Hurlin causality test indicate that environmental sustainability is unidirectionally affected by economic growth. Based on these outcomes, we suggest the following policies:(1) the EU and OECD should implement member-targeted policies on economic growth and fossil-fuel use towards regulating industrial pollution, water use, and population control;and(2) the EU and OECD member countries should invest in environmental technologies through green research and development(R&D) to transform their dirty industrial processes and ensure productive energy use. 展开更多
关键词 Economic growth environment sustainability Decoupling Carbon emissions Eastern Europe Common correlated effect mean group(CCEMG)test Econometrics Population growth
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Stereoscopic Camera-Sensor Model for the Development of Highly Automated Driving Functions within a Virtual Test Environment
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作者 René Degen Martin de Fries +3 位作者 Alexander Nüßgen Marcus Irmer Mats Leijon Margot Ruschitzka 《Journal of Transportation Technologies》 2023年第1期87-114,共28页
The need for efficient and reproducible development processes for sensor and perception systems is growing with their increased use in modern vehicles. Such processes can be achieved by using virtual test environments... The need for efficient and reproducible development processes for sensor and perception systems is growing with their increased use in modern vehicles. Such processes can be achieved by using virtual test environments and virtual sensor models. In the context of this, the present paper documents the development of a sensor model for depth estimation of virtual three-dimensional scenarios. For this purpose, the geometric and algorithmic principles of stereoscopic camera systems are recreated in a virtual form. The model is implemented as a subroutine in the Epic Games Unreal Engine, which is one of the most common Game Engines. Its architecture consists of several independent procedures that enable a local depth estimation, but also a reconstruction of a whole three-dimensional scenery. In addition, a separate programme for calibrating the model is presented. In addition to the basic principles, the architecture and the implementation, this work also documents the evaluation of the model created. It is shown that the model meets specifically defined requirements for real-time capability and the accuracy of the evaluation. Thus, it is suitable for the virtual testing of common algorithms and highly automated driving functions. 展开更多
关键词 Sensor Model Virtual test environment Stereoscopic Camera Unreal Engine OPENCV ADAS/AD
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Site Test of Thermal Environment of Rammed Earth Construction in Anji County of China
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作者 马金柱 高璞 《Journal of Landscape Research》 2012年第4期3-9,共7页
The scientific evaluation on heat insulation and preservation capacity of rammed earth construction can provide an effective evidence for its superiority in preserving thermal environment of the construction. By takin... The scientific evaluation on heat insulation and preservation capacity of rammed earth construction can provide an effective evidence for its superiority in preserving thermal environment of the construction. By taking an eco-hotel in Zhejiang Anji County as the research object, 33 test points have been set. The indoor and outdoor air temperature of eco-hotel and the surface temperature of building envelopes had been recorded by using data acquisition instrument, temperature transmitter and other equipments from January 27 to February 2 in 2007. Then, the data of a period had been selected for comparison and analysis and the results had been obtained as follows. In January when the temperature difference between day and night in Anji was not large, without particular thermal insulation measures and equipments, the indoor temperature of eco-hotel fluctuated very little, showing that rammed earth construction was of obvious capacity for heat preservation and insulation, that its heat stability was evident and that it could ensure excellent indoor thermal environment. 展开更多
关键词 Rammed EARTH construction INDOOR THERMAL environment SITE test
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Laboratory Test on Long-Term Deterioration of Cement Soil in Seawater Environment 被引量:8
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作者 杨俊杰 闫楠 +1 位作者 刘强 张玥宸 《Transactions of Tianjin University》 EI CAS 2016年第2期132-138,共7页
Laboratory tests were conducted to study the effects of curing time, cement ratio and seawater pressure on cement soil deterioration formed at simulative marine soft clay sites. Deterioration depth was determined on t... Laboratory tests were conducted to study the effects of curing time, cement ratio and seawater pressure on cement soil deterioration formed at simulative marine soft clay sites. Deterioration depth was determined on the basis of characteristics of penetration resistance and penetration depth curves, and the deterioration depth of cement soil with the cement ratio of 7%, reached 31.8 mm after 720 d. Results of research indicated that deterioration extended quickly under seawater environment and the deterioration depth increased with the prolonging curing time. In addition, the water pressure could speed up deterioration. With the increase of cement content, the strength of cement soil increased obviously. At the same time, the deterioration depth decreased significantly. The concentration of calcium ion in the cement stabilized soil increased with the increase of depth, while that of magnesium ion gradually decreased. The variations were consistent with energy dispersive spectrometer(EDS)analysis results, and the calcium concentration with depth was in a good consistency with strength distribution at long term. The results showed that the deterioration became more serious with the curing time, and it was related to calcium leaching. 展开更多
关键词 cement soil marine clay deterioration depth micro-cone penetration test seawater environment
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Fieldwork Test Research of the Impact on Building Physical Environment on Six Types of Atrium Space in Cold Climates 被引量:3
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作者 Ye-Hao Song Jun-Jie Li +2 位作者 Ning Zhu Jia-Liang Wang Zheng-Hao Lin 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第4期84-90,共7页
Since the research on verification to passive design strategies in sustainable building is at the initial stage,and its test method and verification conclusion are not scientific enough to validate,this paper proposes... Since the research on verification to passive design strategies in sustainable building is at the initial stage,and its test method and verification conclusion are not scientific enough to validate,this paper proposes the necessity of building physical environmental monitoring to quantitative optimization of passive strategies efficiency from the perspective of architecture design and building environment. Adopting comparative research method,this research chooses six types of atrium space in cold climate in China as a prototype,focusing on building physical environmental performance difference in and between atrium and building main space. Spatial parameters of the atrium space will be divided into four factors: spatial geometry,interfacial properties,internal and external related categories. With subdividing these four factors into sub-factors,this paper makes crosscomparison among the sub-factors to clarify passive strategies effectiveness in atrium. Data comparison analysis shows that Winter atrium passive strategy in cold regions from traditional view is not obvious in practical application,and test data need to be stratified refined in atrium design in case of optimizing passive strategy from building prototype perspective. 展开更多
关键词 atrium space building physical environment fieldwork test space effect
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5G technology requirements and related test environments for evaluation 被引量:2
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作者 Xi Meng Jian Li +1 位作者 Dong Zhou Dacheng Yang 《China Communications》 SCIE CSCD 2016年第S2期42-51,共10页
To meet the considerably increase of mobile data traffic and wireless communication connections around 2020,the 5th generation(5G)mobile network will necessarily consider more frequency bands,enabling technologies and... To meet the considerably increase of mobile data traffic and wireless communication connections around 2020,the 5th generation(5G)mobile network will necessarily consider more frequency bands,enabling technologies and diversified key performance indicators and test environments comparing with existing network,for example Long Term Evolution.More specifically,the obvious difference between 5G and previous wireless communication system are not only included eMBB(enhance mobile broadband) usage scenario,but also introduced mMTC(massive machine type communications)and URLLC(ultra-reliable and low latency communications) usage scenarios.Hence,in order to evaluate 5G related technologies,some novel test environments will be widely discussed,as well as,certain new key performance indicators will be drawn into5 G evaluation methodology for satisfied new requirements.We will discuss characteristic of these 4 candidate test environments,such as indoor isolated environment,high speed train environment;and the definition of 15 keys performance indicator will be explained and clarified,for example,Throughput,Network Energy Efficiency,Device Connection Density and so on.Furthermore,high-level assessment method of each test environment also will be initially considered.It is notable that an initial evaluation of indoor isolated environment also can be found,which the results show that there are 3 times average cell spectral efficiency than IMT-advanced's in same test environment. 展开更多
关键词 5G IMT-2020 test environment requirements key performance indicators
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Realization of Reconfigurable Virtual Environments for Virtual Testing 被引量:2
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作者 Wen-Yan Wu Zheng-Xu Zhao 《International Journal of Automation and computing》 EI 2005年第1期25-36,共12页
This paper presents the design and implementation of reconfigurable virtual environments (VEs) for virtual testing. It proposes a hybrid design approach that is derived from a so-called integration and composition of ... This paper presents the design and implementation of reconfigurable virtual environments (VEs) for virtual testing. It proposes a hybrid design approach that is derived from a so-called integration and composition of the reconfiguration strategy. The designing process has thus evolved from binding virtual objects using reconfiguration rules within the context of virtual testing scenarios. Therefore reconfigurable virtual environments are established with improved flexibility and scalability, tailored to a wide range of virtual testing applications. Those virtual environments integrate virtual testing scenarios, data acquisition, databases, rule mapping and application interfaces, which yield modular testing functions and an open-ended system architecture with a set of extensible interface tools to realize data exchange within reconfigurable VEs. This enables virtual testing scenarios to be reconfigured interactively based on real time data and communication between virtual environments and real environments. A virtual testing application has been implemented using reconfigurable VEs. Keywords Virtual environment - virtual testing - reconfigurable virtual reality Wenyan Wu graduated from Dalian University of Technology, China, with BSc and MSc in 1988 and 1991 respectively. She earned her PhD degree from University of Derby, UK, in 2002. She had taught and researched in Harbin Institute of Technology, China and De Montfort University, UK. She is currently a senior lecturer in simulation and virtual reality at Staffordshire University, UK. Her research interests include computer graphics, Virtual Reality and Augmented Reality system, advanced interface, modelling and simulation, distribution system.Zhengxu Zhao BSc, MSc, PhD, CEng, CITP, MBCS, full Professor in Applied Computing, Director of Virtual Reality Centre. He is also a Cheng Kong Scholar Project Professor in Virtual Reality Technology and Director of Virtual Reality Research Centre at the Southeast University, P R China. Professor Zhao’s research interests include computing graphics and VR systems, industrial process simulation, CIM and manufacturing management systems. 展开更多
关键词 Virtual environment virtual testing reconfigurable virtual reality
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Relationships Between Agronomic and Environmental Soil Test Phosphorus in Three Typical Cultivated Soils in China 被引量:2
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作者 WANG Xin-Min JIE Xiao-Lei +2 位作者 ZHU Yong-Guan HOU Yan-Lin ZHANG Tie-Quan 《Pedosphere》 SCIE CAS CSCD 2008年第6期795-800,共6页
A study was conducted to determine the relationships between agronomic soil test P and environmental soil test P in three soils predominately distributing in three typical agricultural production areas of China. Soil ... A study was conducted to determine the relationships between agronomic soil test P and environmental soil test P in three soils predominately distributing in three typical agricultural production areas of China. Soil P was analyzed using Bray-1 (BP), Olsen (OP), and Mehlich-3 (MP) methods as agronomic tests, and using Fe-oxide impregnated filter paper (FeP), anion-exchange resin membrane (RP), and water (WP) as environmental tests. There were linear relationships between soil P extractable with all the tests evaluated. The regression coefficients, R^2, ranged from 0.8164 to 0.9409 between each two of the agronomic soil test P, and ranged from 0.4702 to 0.8990 between each two of the environmental soil test P, when the three soils were considered separately. When soil test P was analyzed across all the three soils, the highest regression R^2 was found between OP and MP (0.7940) amongst agronomic soil test P, and between FeP and RP amongst environmental soil test P (0.8842). While all of the three agronomic soil test P was linearly related to each of the environmental soil test P across the three soils, strongest relationships were found between OP and environmental soil test P. Agronomic OP may be adopted as an analytical tool for environmental prediction of soil P. 展开更多
关键词 environment PHOSPHORUS testing methods
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Smart projectile acceleration testing in harsh launch environment 被引量:1
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作者 MA Jin PEI Dong-xing +1 位作者 SHEN Da-wei ZHANG Jing 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第2期121-124,共4页
In order to solve the problem of parametric test of smart projectile launch,the launch environment of smart projectile was analyzed.a reasonable and feasible storage testing method was proposed,and a multi-channel tes... In order to solve the problem of parametric test of smart projectile launch,the launch environment of smart projectile was analyzed.a reasonable and feasible storage testing method was proposed,and a multi-channel test system suitable for the environment was designed.The system was successfully applied to a certain range test,and dynamic parameters such as triaxial acceleration of smart projectile launch environment were acquired.The test results play an important role in the improvements of smart projectile design process. 展开更多
关键词 launch environment smart projectile store testing tri-axial acceleration
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The Application of GGE Biplot Analysis for Evaluating Test Locations and Mega-Environment Investigation of Cotton Regional Trials 被引量:15
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作者 XU Nai-yin Fok Michel +2 位作者 ZHANG Guo-wei LI Jian ZHOU Zhi-guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第9期1921-1933,共13页
In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to g... In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to governmental organizations in charge of cultivar registration. Where competition among breeding companies exists, effective and fair multi-environment variety trials are of utmost importance to motivate investment in breeding. The objective of this study was to use genotype main effect plus genotype by environment interaction(GGE) biplot analysis to evaluate test locations in terms of discrimination ability, representativeness and desirability, and to investigate the presence of multiple mega-environments in cotton production in the Yangtze River Valley(YaRV), China. Four traits(cotton lint yield, fiber length, lint breaking tenacity, micronaire) and two composite selection indices were considered. It was found that the assumption of a single mega-environment in the YaRV for cotton production does not hold. The YaRV consists of three cotton mega-environments: a main one represented by 11 locations and two minor ones represented by two test locations each. This demands that the strategy of cotton variety registration or recommendation must be adjusted. GGE biplot analysis has also led to the identification of test location superior for cotton variety evaluation. Although test location desirable for selecting different traits varied greatly, Jinzhou, Hubei Province, China, was found to be desirable for selecting for all traits considered while Jianyang, Sichuan Province, China, was found to be desirable for none. 展开更多
关键词 COTTON multi-environmental trial GGE biplot test location mega-environment
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A test method for evaluating the thermal environment of underground coal mine refuge alternatives
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作者 D.S.Yantek L.Yan +2 位作者 N.W.Damiano M.A.Reyes J.R.Srednicki 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第3期343-355,共13页
Since 2009,the Mine Safety and Health Administration(MSHA)has required mines to install refuge alternatives(RAs)in underground coal mines.One of the biggest concerns with occupied RAs is the possible severity of the r... Since 2009,the Mine Safety and Health Administration(MSHA)has required mines to install refuge alternatives(RAs)in underground coal mines.One of the biggest concerns with occupied RAs is the possible severity of the resulting thermal environment.In 30 CFR 7.504,the maximum allowable apparent temperature(AT)for an occupied RA is specified as 35℃(95°F).Manufacturers must conduct heat/humidity tests to demonstrate that their RAs meet the 35℃(95°F)AT limit.For these tests,heat input devices are used to input the metabolic heat of actual miners.A wide variety of test methods,sensors,and heat input devices could be used when conducting such tests.Since 2012,the National Institute for Occupational Safety and Health(NIOSH)has conducted over thirty 96-hour heat/humidity tests on four different RAs.This paper discusses the test equipment and procedures used during these investigations.This information is useful for RA manufacturers conducting RA heat/humidity tests,for other researchers investigating RA heat/humidity buildup,and for those who need to assess the thermal environment of any confined space where people may be trapped or are seeking refuge. 展开更多
关键词 REFUGE CHAMBER REFUGE ALTERNATIVE CONFINED space THERMAL environment test method Temperature
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Tribological behaviors of hydrogenated diamond-like carbon films in different testing environments
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作者 CHEN Jian-min LI Hong-xuan +2 位作者 XU Tao ZHOU Hui-di LIU Hui-wen 《中国有色金属学会会刊:英文版》 CSCD 2004年第z1期341-347,共7页
Hydrogenated diamond-like carbon (DLC) films were deposited on Si substrate using plasma enhanced chemical vapor deposition(PECVD) technique with CH4 plus H2 as the feedstock. The tribological properties of the hydrog... Hydrogenated diamond-like carbon (DLC) films were deposited on Si substrate using plasma enhanced chemical vapor deposition(PECVD) technique with CH4 plus H2 as the feedstock. The tribological properties of the hydrogenated DLC films were measured on a ball-on-disk tribometer in different testing environments (humid air,dry air, dry O2, dry Ar and dry N2 ) sliding against Si3 N4 balls. The friction surfaces of the films and Si3 N4 balls were observed on a scanning electron microscope (SEM) and investigated by X-ray photoelectron spectroscopy (XPS). The results show that the tribological properties of the hydrogenated DLC films are strongly dependent on the testing environments. In dry Ar and dry N2 environments, the hydrogenated DLC films provide a superlow friction coefficient of about 0. 008 -0.01 and excellent wear resistance (wear life of above 56 km). In dry air and dry O2, the friction coefficient is increased to 0. 025 - 0.04 and the wear life is decreased to about 30 km. When sliding in moist air, the friction coefficient of the films is further increased to 0. 08 and the wear life is decreased to 10. 4 km. SEM and XPS analyses show that the tribological behaviors appear to rely on the transferred carbon-rich layer processes on the Si3 N4 balls and on the friction-induced oxidation of the films controlled by the nature of the testing environments. 展开更多
关键词 hydrogenated DLC films tribological behaviors testing environments PECVD
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A Test Bed for Information Security Skill Development with Virtual Training Environment
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作者 Alok Tripathi Abhinav Mishra Gudalur Varadarajan Raghunathan 《Computer Technology and Application》 2011年第6期449-455,共7页
New attacks are emerging rapidly in Information Security; hence the tools and technologies available for securing the information needs substantial upgradation as well as skills for operationalization to mitigate thes... New attacks are emerging rapidly in Information Security; hence the tools and technologies available for securing the information needs substantial upgradation as well as skills for operationalization to mitigate these attacks. It requires creation of practical training environment with tools and technologies available for Information Security. The design of Information Security courses involves scenario based hands-on-labs with real time security incidents and problems with global reach which could be customized quickly as per the scenario and user's requirement. In order to understand the underlying concepts as well as to learn the practical aspects of network and system security environment, an initiative has been taken and a Virtual Test Bed has been developed to meet the above objectives. It is an essential component in Information Security training concept which could be used to perform actual security attacks and remedial measures as well as to test the effectiveness of protection mechanisms and help in handling the security incidents effectively. This paper discusses the development of this Test Bed for Information Security skill development with virtual training environment using which Information Security concepts, attacks on networks/systems and practical scenarios are simulated for imparting hands on training to participants. 展开更多
关键词 ATTACKS information security test bed virtual training environment SIMULATION
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The dynamic analysis of natural environment change of nuclear test field in Lop Nur region of China
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作者 Hu Dongsheng Pang Xilei +5 位作者 Zhang Huajing Xu Bing Yu Xuefeng Tian Xinhong An Zhisheng Zhang Guowei 《Engineering Sciences》 EI 2008年第3期37-44,共8页
Using earth satellite observation means, remote sensing information distilled technique and regional research production, we have roundly analyzed and made an integrated evaluation about the Lop Nur nuclear test field... Using earth satellite observation means, remote sensing information distilled technique and regional research production, we have roundly analyzed and made an integrated evaluation about the Lop Nur nuclear test field in western China. This product reveals the rarely-known nuke explosion effect and response events of geology conditions. It also offers us legible and practical first-hand materials about human extreme effects, important engineering environment and intimidating influence process. By excavating and appraising the materials gradually on the natural environment factors changing in the test field through macroscopic elimination and typical filtration, it can supply basic scientific data for security of national nuclear usage, appraising the nuclear environment synthetically and developing nuclear strategy expediently. 展开更多
关键词 earth's satellite observation the nuclear test field the nuke explosion effect and the response process of geological environment comprehensive evaluation of natural resource environment Lop Nut region of China
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Dynamic behavior of new cutting subgrade structure of expensive soil under train loads coupling with service environment 被引量:16
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作者 QIU Ming-ming YANG Guo-lin +3 位作者 SHEN Quan YANG Xiao WANG Gang LIN Yu-liang 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期875-890,共16页
Expansive soil is sensitive to dry and wet environment change. And the volume deformation and inflation pressure of expansive soil may induce to cause the deformation failure of roadbed or many other adverse effects. ... Expansive soil is sensitive to dry and wet environment change. And the volume deformation and inflation pressure of expansive soil may induce to cause the deformation failure of roadbed or many other adverse effects. Aimed at a high-speed railway engineering practice in the newly built Yun-Gui high-speed railway expansive soil section in China, indoor vibration test on a full-scaled new cutting subgrade model is carried out. Based on the established track-subgrade-foundation of expansive soil system dynamic model test platform, dynamic behavior of new cutting subgrade structure under train loads coupling with extreme service environment(dry, raining, and groundwater level rising) is analyzed comparatively. The results show that the subgrade dynamic response is significantly influenced by service conditions and the dynamic response of subgrade gradually becomes stable with the increasing vibration times under various service environment conditions. The vertical dynamic soil stress is related with the depth in an approximate exponential function, and the curves of vertical dynamic soil stress present a "Z" shape distribution along transverse distance. The peak value of dynamic soil stress appears below the rail, and it increases more obviously near the roadbed surface. However, the peak value of dynamic soil stress is little affected outside 5.0 m of center line. The vibration velocity and acceleration are in a quadratic curve with an increase in depth, and the raining and groundwater level rising increase both the vibration velocity and the acceleration. The vertical deformations at different depths are differently affected by service environment in roadbed. The deformation of roadbed increases sharply when the water gets in the foundation of expansive soil, and more than 60% of the total deformation of roadbed occurs in expansive soil foundation. The laid waterproofing and drainage structure layer, which weakens the dynamic stress and improves the track regularity, presents a positive effect on the control deformation of roadbed surface. An improved empirical formula is then proposed to predict the dynamic stress of ballasted tracks subgrade of expansive soil. 展开更多
关键词 high-speed RAILWAY FULL-SCALE model testing dynamic response expansive SOIL service environment NEW SUBGRADE structure
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An enriched environment increases the expression of fibronectin type Ⅲ domain-containing protein 5 and brain-derived neurotrophic factor in the cerebral cortex of the ischemic mouse brain 被引量:12
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作者 Ke-Wei Yu Chuan-Jie Wang +7 位作者 Yi Wu Yu-Yang Wang Nian-Hong Wang Shen-Yi Kuang Gang Liu Hong-Yu Xie Cong-Yu Jiang Jun-Fa Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第9期1671-1677,共7页
Many studies have shown that fibronectin type III domain-containing protein 5(FDNC5) and brain-derived neurotrophic factor(BDNF) play vital roles in plasticity after brain injury. An enriched environment refers to an ... Many studies have shown that fibronectin type III domain-containing protein 5(FDNC5) and brain-derived neurotrophic factor(BDNF) play vital roles in plasticity after brain injury. An enriched environment refers to an environment that provides animals with multi-sensory stimulation and movement opportunities. An enriched environment has been shown to promote the regeneration of nerve cells, synapses, and blood vessels in the animal brain after cerebral ischemia;however, the exact mechanisms have not been clarified. This study aimed to determine whether an enriched environment could improve neurobehavioral functions after the experimental inducement of cerebral ischemia and whether neurobehavioral outcomes were associated with the expression of FDNC5 and BDNF. This study established ischemic mouse models using permanent middle cerebral artery occlusion(pMCAO) on the left side. On postoperative day 1, the mice were randomly assigned to either enriched environment or standard housing condition groups. Mice in the standard housing condition group were housed and fed under standard conditions. Mice in the enriched environment group were housed in a large cage, containing various toys, and fed with a standard diet. Sham-operated mice received the same procedure, but without artery occlusion, and were housed and fed under standard conditions. On postoperative days 7 and 14, a beam-walking test was used to assess coordination, balance, and spatial learning. On postoperative days 16–20, a Morris water maze test was used to assess spatial learning and memory. On postoperative day 15, the expression levels of FDNC5 and BDNF proteins in the ipsilateral cerebral cortex were analyzed by western blot assay. The results showed that compared with the standard housing condition group, the motor balance and coordination functions(based on beam-walking test scores 7 and 14 days after operation), spatial learning abilities(based on the spatial learning scores from the Morris water maze test 16–19 days after operation), and memory abilities(based on the memory scores of the Morris water maze test 20 days after operation) of the enriched environment group improved significantly. In addition, the expression levels of FDNC5 and BDNF proteins in the ipsilateral cerebral cortex increased in the enriched environment group compared with those in the standard housing condition group. Furthermore, the Pearson correlation coefficient showed that neurobehavioral functions were positively associated with the expression levels of FDNC5 and BDNF(r = 0.587 and r = 0.840, respectively). These findings suggest that an enriched environment upregulates FDNC5 protein expression in the ipsilateral cerebral cortex after cerebral ischemia, which then activates BDNF protein expression, improving neurological function. BDNF protein expression was positively correlated with improved neurological function. The experimental protocols were approved by the Institutional Animal Care and Use Committee of Fudan University, China(approval Nos. 20160858 A232, 20160860 A234) on February 24, 2016. 展开更多
关键词 beam-walking test brain-derived neurotrophic factor cerebral ischemia correlation analysis enriched environment fibronectin typeⅢdomain-containing protein 5 Morris water maze task neural plasticity NEUROPROTECTION permanent middle cerebral artery occlusion
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Effect of drying environment on engineering properties of an expansive soil and its microstructure 被引量:11
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作者 KONG Ling-wei WANG Min +1 位作者 GUO Ai-guo WANG Yong 《Journal of Mountain Science》 SCIE CSCD 2017年第6期1194-1201,共8页
This paper investigates the effect of drying environment, i.e. temperature and relative humidity, on the engineering properties and microscopic pore size distribution of an expansive soil. The shrinkage tests under di... This paper investigates the effect of drying environment, i.e. temperature and relative humidity, on the engineering properties and microscopic pore size distribution of an expansive soil. The shrinkage tests under different drying temperatures and relative humidity are carried out in a constant climate chamber. Then, the undisturbed samples, prepared in different drying environment, are used for the triaxial tests and mercury intrusion tests. It is found that the drying environment has noticeable influence on the engineering properties of expansive soils and it can be characterized by the drying rate. The linear shrinkage and strength increase with the decrease of the drying rate. The non-uniform deformation tends to happen in the high drying rate, which subsequently furthers the development of cracks. In addition, during the drying process, the variation of pores mainly focuses on the inter-aggregate pores and inter-particle pores. The lower drying rate leads to larger variation of pore size distribution. 展开更多
关键词 Expansive soils Drying environment Shrinkage Strength Pore size distribution Triaxial test
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Temporal and Spatial Factors Affecting the Nature of Genotype x Environment Interaction in Sugarcane (<i>Saccharum officinarum L.</i>) under Ethiopian Agro-Climatic Conditions: An Integrated Approach 被引量:1
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作者 Mebrahtom Ftwi Firew Mekbib Eyasu Abraha 《American Journal of Plant Sciences》 2017年第7期1721-1749,共29页
Analytical approaches are important for identification the causes of Genotype x environment interaction (GEI) in multi-environment trials (MET). The objectives of this investigation were to explore the nature and caus... Analytical approaches are important for identification the causes of Genotype x environment interaction (GEI) in multi-environment trials (MET). The objectives of this investigation were to explore the nature and causes of the GEI in sugarcane under Ethiopian agro ecological conditions. Data of Cane yield, recoverable sucrose% and sugar yield obtained from 13 test environments were subjected to Additive Main and Multiplicative Interaction (AMMI2) for empirical study. For environmental characterization, mean values of twenty seven temporal and spatial factors were subjected to Principal Component Analysis (PCA). Moreover, to identify the environmental factors affecting the patterns of GEI and its components, mean values of these factors were correlated with environment AMMI2 IPCA scores of the yield traits studied. Results of the present study indicated that the GEI accounted for larger variation than the genotypic effects which suggested its importance and complexity. The PCA bi-plot successfully identified the environmental factors that most discriminated the test environments (crop years and locations). The correlation analysis between the environmental factors and environmental AMMI2 IPCA scores adequately identified the environmental factors affecting GEI and its components. Soil organic matter% and soil clay%, pan evaporation at establishment, relative humidity at growth stage and harvesting month were the major factors that substantially affect the GEI interaction patterns in cane yield while maximum relative humidity recorded during the growing season, all temperature regimes recorded during the entire growing season and at different crop stages were the major factors that affect GEI in recoverable sucrose%. Moreover, the pattern of GEI in sugar yield was significantly affected by harvest age, percent of clay in soil, altitude, relative humidity at harvest and pan evaporation at establishment. For efficient environmental selection and networks, genotype evaluations and formulation of appropriate sugarcane breeding strategy, f METs should adopt the inclusion of these environmental factors identified as major factors influencing the patterns of GEI. Moreover, more information will be generated if other physiological and soil moisture stress indices are included in future GEI studies in sugarcane. 展开更多
关键词 AMMI Bi-Plots environmental COVARIATES Genotypes MET PCA Bi-Plots test environments
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Problems Related to Divers Health and Comfort in Hyperbaric He-O_2 Environment
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作者 Mao Fangguan Senior Engineer, The Naval Medical Research Institute, Chinese People’s Liberation Army, Shanghai, 200433 《China Ocean Engineering》 SCIE EI 1996年第4期495-496,共2页
The Diver Gas Recovery System(DGRS)is an important accessory equipment of the 300m Saturation Dive System. The system facilitates the recycling of the breathing gases for divers,therefore,it has great economic benefit... The Diver Gas Recovery System(DGRS)is an important accessory equipment of the 300m Saturation Dive System. The system facilitates the recycling of the breathing gases for divers,therefore,it has great economic benefits. In April 1995, a 300 m unmanned test and a 100 m manned test on the HY2031 DGRSwere carried out successively.Ten months later,another manned test on the HY2032 DGRS 展开更多
关键词 test Problems Related to Divers Health and Comfort in Hyperbaric He-O2 environment
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Physical characteristics of high concentrated gas hydrate reservoir in the Shenhu production test area,South China Sea
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作者 Jiapeng JIN Xiujuan WANG +7 位作者 Zhenyu ZHU Pibo SU Lixia LI Qingping LI Yiqun GUO Jin QIAN Zhendong LUAN Jilin ZHOU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第2期694-709,共16页
High concentrated and heterogeneous distribution of gas hydrates have been identified in the gas hydrate production test region in the Shenhu area,South China Sea.The gas hydrate-bearing sediments with high saturation... High concentrated and heterogeneous distribution of gas hydrates have been identified in the gas hydrate production test region in the Shenhu area,South China Sea.The gas hydrate-bearing sediments with high saturation locate at two ridges of submarine canyon with different thickness and saturations just above the bottom simulating reflection.The crossplots of gamma ray,acoustic impedance(P-impedance)and porosity at four sites show that the sediments can be divided into the upper and lower layers at different depths,indicating different geotechnical reservoir properties.Therefore,the depositional environments and physical properties at two ridges are analyzed and compared to show the different characteristics of hydrate reservoir.High porosity,high P-wave velocity,and coarse grain size indicate better reservoir quality and higher energy depositional environment for gas hydrate at Sites W18 and W19 than those at Sites W11 and W17.Our interpretation is that the base of canyon deposits at Sites W18 and W19 characterized by upward-coarsening units may be turbidity sand layers,thus significantly improving the reservoir quality with increasing gas hydrate saturation.The shelf and slope sliding deposits compose of the fine-grained sediments at Sites W11 and W17.The gas hydrate production test sites were conducted at the ridge of W11 and W17,mainly because of the thicker and larger area of gas hydrate-bearing reservoirs than those at Sites W18 and W19.All the results provide useful insights for assessing reservoir quality in the Shenhu area. 展开更多
关键词 reservoir properties gas hydrate production test region depositional environment South China Sea
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