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三峡库区山区农业生态系统转型 认领
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作者 梁鑫源 李阳兵 +1 位作者 邵景安 冉彩虹 《地理学报:英文版》 SCIE CSCD 2020年第2期281-296,共16页
The Three Gorges Reservoir Area(TGRA)is typical of an ecologically vulnerable area,comprised of rural and mountainous areas,and with high immigration.Because of its economic and ecologic importance,studying the tradit... The Three Gorges Reservoir Area(TGRA)is typical of an ecologically vulnerable area,comprised of rural and mountainous areas,and with high immigration.Because of its economic and ecologic importance,studying the traditional agroecosystem changes in the TGRA is key to rural development and revitalization.In this study,we apply a framework of theoretical analysis,empirical study,and trend prediction to the Caotangxi River watershed within the TGRA.Using QuickBird high-resolution remote sensing images from 2012 to 2017 to evaluate natural resources and farmers’behavior,we analyze the transition and trends in the traditional agroecosystem in mountainous areas of the TGRA at spatial scale of the man-land relationship.We find that the agroecosystem in the TGRA can be divided into four modes using 100 m interval buffer rings:high-low-low,high-low-high,low-high-low and low-low-high mode where the different modes represent the agricultural development stages in the TGRA.Furthermore,the traditional agroecosystem in TGRA,represented by system elements such as farmers and sloping farmland,is transforming to accommodate the diversification of farmer livelihoods.For example,sloping farmland,which was dominated by a production function,now has equal emphasis on ecological and economic functions.Spatially,the range of the agroecosystem transition has migrated beyond high mountain areas to flat valley areas.Generally,this study provides an overview of land use in rural areas,controls on soil and water loss in mountainous areas,and better rural living environments in the TGRA. 展开更多
关键词 Three Gorges RESERVOIR Area ecologically fragile area mountainous area TRADITIONAL AGROECOSYSTEM TRANSITION empirical study SPATIAL scale
FTA建设下中国与斯里兰卡经贸合作的问题及对策研究 认领
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作者 赵青松 郭婉茹 《天津商务职业学院学报》 2020年第1期33-40,共8页
作为连接亚非欧海上航路的枢纽,斯里兰卡具有重要的地缘优势和战略合作价值。近年来,中斯双边贸易增长迅速,两国贸易互补性强;中方对斯投资持续增长,现已成为其最大投资国和基础设施建设合作伙伴。虽然中斯双方已经举行五轮FTA谈判,但... 作为连接亚非欧海上航路的枢纽,斯里兰卡具有重要的地缘优势和战略合作价值。近年来,中斯双边贸易增长迅速,两国贸易互补性强;中方对斯投资持续增长,现已成为其最大投资国和基础设施建设合作伙伴。虽然中斯双方已经举行五轮FTA谈判,但在自贸区降税范围上仍存在分歧,为此,中斯两国应扩大农产品贸易,加强纺织业、旅游业等领域的合作,深化中方对斯投资及工程承包合作,推动"一带一路"倡议与斯里兰卡"愿景2025"计划的合作对接,加快中斯双边自贸区谈判。 展开更多
关键词 FTA(Free TRADE Area) 中国 斯里兰卡 自由贸易区 经贸合作
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Changes in sensorimotor regions of the cerebral cortex in congenital amusia:a case-control study 认领
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作者 Jun-Jie Sun Xue-Qun Pan +4 位作者 Ru Yang Zhi-Shuai Jin Yi-Hui Li Jun Liu Da-Xing Wu 《中国神经再生研究:英文版》 SCIE CAS 2021年第3期531-536,共6页
Perceiving pitch is a central function of the human auditory system;congenital amusia is a disorder of pitch perception.The underlying neural mechanisms of congenital amusia have been actively discussed.However,little... Perceiving pitch is a central function of the human auditory system;congenital amusia is a disorder of pitch perception.The underlying neural mechanisms of congenital amusia have been actively discussed.However,little attention has been paid to the changes in the motor rain within congenital amusia.In this case-control study,17 participants with congenital amusia and 14 healthy controls underwent functional magnetic resonance imaging while resting with their eyes closed.A voxel-based degree centrality method was used to identify abnormal functional network centrality by comparing degree centrality values between the congenital amusia group and the healthy control group.We found decreased degree centrality values in the right primary sensorimotor areas in participants with congenital amusia relative to controls,indicating potentially decreased centrality of the corresponding brain regions in the auditory-sensory motor feedback network.We found a significant positive correlation between the degree centrality values and the Montreal Battery of Evaluation of Amusia scores.In conclusion,our study identified novel,hitherto undiscussed candidate brain regions that may partly contribute to or be modulated by congenital amusia.Our evidence supports the view that sensorimotor coupling plays an important role in memory and musical discrimination.The study was approved by the Ethics Committee of the Second Xiangya Hospital,Central South University,China(No.WDX20180101GZ01)on February 9,2019. 展开更多
关键词 congenital amusia degree centrality lifelong impairment local functional connectivity music discrimination primary motor area primary sensorimotor area primary sensory area resting-state functional magnetic resonance imaging voxel-based analysis
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Removal of Dyes from Wastewater by Adsorption onto Activated Carbon: Mini Review 认领
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作者 Soonmin Ho 《地球科学和环境保护期刊(英文)》 2020年第5期120-131,共12页
Nowadays, wastewater from dyeing industries became a challenging issue in the world. Researchers have reported several techniques to treat those effluents based on their projects. Adsorption is the most common method ... Nowadays, wastewater from dyeing industries became a challenging issue in the world. Researchers have reported several techniques to treat those effluents based on their projects. Adsorption is the most common method because of cheap, simple and effective method. In this work, activated carbon was used for dye adsorption purpose. This adsorbent has high surface area and high porosity to remove dye. This review highlighted some important results of the last few years regarding the use of activated carbon in wastewater treatment. Research findings supported that adsorption process is spontaneous in nature. Adsorption data confirmed Langmuir model, indicating the chemisorption occurred. 展开更多
关键词 ACTIVATED Carbon WASTEWATER Treatment DYE ADSORPTION Surface Area
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Real Time Vehicular Traffic Simulation for Black Hole Attack in the Greater Detroit Area 认领
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作者 Abdulaziz Alshammari Mohamed A Zohdy +1 位作者 Debatosh Debnath George Corser 《信息安全(英文)》 2020年第1期71-80,共10页
Vehicular Ad-hoc Networks (VANETs) technology has recently emerged, and gaining significant attention from the research because it is promising technologies related to Intelligent Transportation System (ITSs) and smar... Vehicular Ad-hoc Networks (VANETs) technology has recently emerged, and gaining significant attention from the research because it is promising technologies related to Intelligent Transportation System (ITSs) and smart cities. Wireless vehicular communication is employed to improve traffic safety and to reduce traffic congestion. Each vehicle in the ad-hoc network achieves as a smart mobile node categorized by high mobility and forming of dynamic networks. As a result of the movement of vehicles in a continuous way, VANETs are vulnerable to many security threats so it requisites capable and secure communication. Unfortunately, Ad hoc networks are liable to varied attacks like Block Hole attacks and Grey Hole attacks, Denial of service attacks, etc. Among the most known attacks are the Black Hole attacks while the malicious vehicle is able to intercept the data and drops it without forwarding it to the cars. The main goal of our simulation is to analyze the performance impact of black hole attack in real time vehicular traffic in the Greater Detroit Area using NS-2 and SUMO (Simulation of Urban). The simulation will be with AODV protocol. 展开更多
关键词 Black Hole ATTACKS Vehicular Ad Hoc Networks AODV Protocol SIMULATION SUMO GREATER DETROIT Area
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Breakthrough of shallow shale gas exploration in Taiyang anticline area and its significance for resource development in Zhaotong, Yunnan Province, China 认领
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作者 LIANG Xing XU Zhengyu +8 位作者 ZHANG Zhao WANG Weixu ZHANG Jiehui LU Huili ZHANG Lei ZOU Chen WANG Gaocheng MEI Jue RUI Yun 《石油勘探与开发:英文版》 2020年第1期12-29,共18页
Based on exploration and development results and evaluation of marine shale gas in South China in the past ten years, in view of the features of "high maturity, strong tectonic reformation and high shear stress&q... Based on exploration and development results and evaluation of marine shale gas in South China in the past ten years, in view of the features of "high maturity, strong tectonic reformation and high shear stress" of the shale in Zhaotong exploration zone in the Yunnan and Guizhou Plateau, as well as the key issues of long time diffusion and leakage of shallow shale gas, and the preservation conditions, the factors controlling shallow shale gas sweet spot and key zone selection evaluation technology of shale gas are investigated. From 2017 to 2018, the first significant exploration breakthrough was made in the Taiyang anticline at a buried depth of 700 to 2 000 m, discovering large-scale proved geological reserves of shallow shale gas. By examining the accumulation conditions and sweet spot control factors of the shallow shale gas in this area, it is found that the accumulation and productivity potential of shale gas in the mountainous area with complex structure outside basin are controlled by five factors:(1) The gas-rich area has weak tectonic reformation and good preservation conditions on the whole, taking on typical anticline trap occurrence mode.(2) The gas-rich area is in over-pressure state and high in shale gas content.(3) The gas-rich area has high quality shale and thus superior source rock condition.(4) The gas-rich area has high quality reservoirs dominated by class I.(5) The shale gas reservoir in the gas-rich area has high content of brittle minerals and small difference between maximum and minimum horizontal stresses which are conducive to hydraulic fracturing. The innovative practice and core technologies formed during the exploration and production capacity construction of shallow shale gas in the Zhaotong demonstration zone have great reference significance for shallow shale gas exploration and development in other areas. 展开更多
关键词 SHALLOW shale gas SILURIAN Longmaxi FORMATION Ordovician Wufeng FORMATION EXPLORATION BREAKTHROUGH Taiyang ANTICLINE area Zhaotong area ANTICLINE
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Leaf area index estimated by direct, semi-direct, and indirect methods in European beech and sycamore maple stands 认领
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作者 Jakub Cerny Pavel Haninec Radek Pokorny 《林业研究:英文版》 SCIE CAS CSCD 2020年第3期827-836,共10页
Leaf area index(LAI)is one of the most important characteristics of forest stands that affects the fundamentals of tree physiological processes,biomass production,and mechanical stability.The LAI results obtained by t... Leaf area index(LAI)is one of the most important characteristics of forest stands that affects the fundamentals of tree physiological processes,biomass production,and mechanical stability.The LAI results obtained by the semi-direct and indirect methods(the needle technique and an LAI-2000 PCA)in three European beech(Fagus sylvatica L.)stands and one sycamore maple(Acer pseudoplatanus L.)stand were compared with LAI estimated by litter traps during the 2013 growing season.Seasonal LAI was estimated using an LAI-2000 PCA which showed similar trends among the stands and strongly corresponded to phenological phases of deciduous stands in Europe,with the fastest rate of leaf area increment occurring during the first month following bud break.During the growing season,maximum stand LAI value was on June 19th and reached 4.5–5.1,and 4.0 in the beech and maple stands,respectively.The needle technique significantly underestimated(p<0.05)direct LAI on average by 22.0% and 40.0% in the beech and maple stands,respectively.The LAI-2000 PCA insignificantly underestimated(p>05)LAI on average by 15.1%and 5.8%in the beech and maple stands,respectively.All methods for LAI estimation at the stand level could be applicable in deciduous forest stands(beech,maple)with similar site and stand characteristics.However,calibration by direct method is necessary to obtain the required precision. 展开更多
关键词 LEAF area index Specific LEAF area LITTER TRAP Needle technique LAI-2000 PCA
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Urbanization and eco-environment coupling circle theory and coupler regulation 认领
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作者 FANG Chuanglin CUI Xuegang +1 位作者 DENG Xiangzheng LIANG Longwu 《地理学报:英文版》 SCIE CSCD 2020年第7期1043-1059,共17页
A near-distance,nonlinear coupling relationship objectively exists between urbanization and the eco-environment.The issue of how to coordinate the relationship between them has become a global strategic and scientific... A near-distance,nonlinear coupling relationship objectively exists between urbanization and the eco-environment.The issue of how to coordinate the relationship between them has become a global strategic and scientific issue.This study reveals the nature,relationship and intensity of coupling between urbanization and the eco-environment from a theoretical perspective.Based on the strength of coupling,relationships can be characterized as having very-low,low,medium,high,very-high or full coupling intensity,which correspond to the categories of random coupling,indirect coupling,loose coupling,cooperative coupling,close coupling,and controlled coupling.Together,these make up an urbanization and eco-environment"coupling tower."This study also develops an urbanization and eco-environment coupling circle theory and generates 45 coupling graphs(including linear,exponential-curve,logarithmic-curve,double exponential-curve and S-curve graphs)per 10°of rotation of the coupling circle,with different graphs corresponding to different urban development stages and development models.Of the various coupling graphs,the S-curve graph is considered the optimum,as it reflects the best interactivity scenario between urbanization and the eco-environment.Using an S-curve coupling graph,and with the help of an SD model and based on the complex one-to-one,one-to-many,and many-to-many relationships between the variables,this study develops the Urbanization and Eco-environment Coupler(UEC).The UEC is composed of 11 regulating elements and 201 variables.If one variable changes,it changes the whole,affecting the structure,function and regulation of the entire coupler.The UEC includes three spatio-temporal scales:static regulation between multiple urbanization areas and eco-environment areas at the same time,dynamic regulation between the same urbanization area and eco-environment area at different times,and dynamic regulation between multiple urbanization areas and eco-environment areas at different times.Regulation gradually promotes evolu 展开更多
关键词 coupling circle theory coupler regulation urbanization area eco-environment area
Relationship between the Northern Hemisphere Sea Ice Area and Global Temperature by Multifractal Analysis 认领
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作者 Fumio Maruyama 《应用数学与应用物理(英文)》 2020年第5期896-909,共14页
Changes in Arctic sea ice are an important fingerprint of natural and anthropogenic climate change. In general, fractal properties may be observed in the time series of the dynamics of complex systems. To study the re... Changes in Arctic sea ice are an important fingerprint of natural and anthropogenic climate change. In general, fractal properties may be observed in the time series of the dynamics of complex systems. To study the relations among the Northern Hemisphere (NH) sea ice area, solar activity, global temperature, and Pacific Decadal Oscillation (PDO) index, we investigated changes in the fractal behavior of these time series by multifractal analysis and applying the wavelet coherence. The relationship between the solar activity: solar flux, sunspot number (SSN), and ultraviolet B (UV-B), and NH sea ice area was assessed based on changes in fractality. We identified the existing relations among the NH sea ice area, global temperature, and PDO based on changes in fractality and wavelet coherence. In the 2000s when the global warming hiatus occurred, after the order formation of NH sea ice area in the early 2000s, the change in state from multifractal to monofractal of the PDO and global temperature occurred, when fluctuations became large and multifractality became strong. We identified a small change in fractality for NH sea ice area, UV-B, and global temperature and a large change in fractality for solar flux, SSN, and PDO, which had large fluctuation. Our results will contribute to further studies on climate change. 展开更多
关键词 NH Sea ICE Area Solar FLUX Global Temperature PDO WAVELET MULTIFRACTAL
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Distribution of Radioactive Elements and Their Relation to the Radiogenic Heat Production at Jabal Kharazah Area, North Eastern Desert, Egypt 认领
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作者 Mohamed A. Shaheen 《地球科学和环境保护期刊(英文)》 2020年第4期155-168,共14页
A map of radiogenic heat production RHP was constructed from airborne spectral gamma-ray data of Jabal Kharazah area, North Eastern Desert, Egypt. The study area possesses a range of RHP varying from 0.2 to 5.7 μW/m-... A map of radiogenic heat production RHP was constructed from airborne spectral gamma-ray data of Jabal Kharazah area, North Eastern Desert, Egypt. The study area possesses a range of RHP varying from 0.2 to 5.7 μW/m-3 with an average value 1.38 μW/m-3, while the standard deviation value is 0.7 μW/m-3. The maximum values are associated with the acidic rocks in the northeast, southeast and a small portion in the northwest zones. About 68% of the readings are higher than the average RHP value in the area, thus Jabal Kharazah area can be considered as heat production area due to the relatively high radioactive mineral concentrations. There are excellent relationships between the derived RHP and the three radioactive elements, Uranium (eU), Thorium (eTh) and Potassium (K). 展开更多
关键词 Radiogenic Heat Production RHP Jabal Kharazah Area AIRBORNE SPECTRAL GAMMA-RAY
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Interest of Splitting the Enthalpies of Vaporization in Four Distinct Parts Reflecting the Van der Waals and the Hydrogen Bonding Forces 认领
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作者 Paul Laffort 《物理化学期刊(英文)》 2020年第2期117-137,共21页
An experimental characterization of the Van der Waals forces involved in volatile organic compounds (VOC) dissolved into stationary phases of gas liquid chromatography (GLC) has been started at the beginning of the se... An experimental characterization of the Van der Waals forces involved in volatile organic compounds (VOC) dissolved into stationary phases of gas liquid chromatography (GLC) has been started at the beginning of the seventies. This field has been reactivated from 1994 thanks to a fruitful cooperation between our CNRS team and the group of Ervin Kováts at the Federal Polytechnic School of Lausanne. The applied strategy can be summarized, in the first instance, as the experimental measurement of accurate and superabundant mutual affinities of a limited number of VOC and stationary phases and their processing using an original tool named Multiplicative Matrix Analysis (MMA). Then, in the second stage, the obtained results have been compared with molecular properties well established, as the Van der Waals molecular volume, the refraction index and the polar surface area (PSA), in order to get generalized values for any compound. The present study summarizes the positive results developed in our three last papers on this topic (2013, 2016 and 2018), as well as the attempt to overcome the negative ones using enthalpies of vaporization. 展开更多
关键词 Enthalpy of VAPORIZATION Van der WAALS Intermolecular FORCES Molecular Polarity Polar Surface Area GAS-LIQUID Chromatography Chemo-Informatics OLFACTION
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Modeling Secure Home Area Network Based on IoT for Resource Constraints Environment 认领
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作者 Minsu Park Mwawi Kayuni +1 位作者 Tiwonge Manda Hyunsung Kim 《电脑和通信(英文)》 2020年第1期45-70,共26页
The Internet of things (IoT) can be used in our daily life. Home area network (HAN) is one of the applications of loT. However, deploying HAN for underdeveloped countries in Africa is not easy due to the lack of Inter... The Internet of things (IoT) can be used in our daily life. Home area network (HAN) is one of the applications of loT. However, deploying HAN for underdeveloped countries in Africa is not easy due to the lack of Internet connectivity and stable electricity. First of all, Internet in Africa is growing fast but the majority of countries in Africa have Internet penetration of less than 10%. Furthermore, the problem of accessing electricity varies greatly across African countries, which is still less than 30% of the average usage rate. The aim of this paper is to model a secure HAN based on IoT for resource constraints environment, which are focused on both network connectivity and energy stability. Poor connectivity, the prevalence of low-end devices and several other obstacles should be considered for the secure HAN deployment in developing and underdeveloped countries. The proposed HAN model will provide the resource constraints module composed of network connectivity function and energy stability function to support the two constraints based on the IoT basic module and the security and privacy module. The proposed HAN model could be securely applied to various countries HAN applications with poor electricity supply and network connectivity. 展开更多
关键词 HOME Area NETWORK Security PRIVACY Internet of THINGS DELEGATION
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Research on Improvement of Utilization of Open Space: Through Demonstration Experiment Focusing on Spatial Elements 认领
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作者 Yuka Kimura Yuichi Sueshige +2 位作者 Eisuke Aoki Yusuke Inaduka Hideaki Takayanagi 《土木工程与建筑:英文版》 2020年第3期153-159,共7页
Along with the rise of buildings, a large number of public open spaces have been created for the purpose of mitigating hatching restrictions and the like. However, many of them are used at low levels, and there remain... Along with the rise of buildings, a large number of public open spaces have been created for the purpose of mitigating hatching restrictions and the like. However, many of them are used at low levels, and there remain very few known public open spaces. In this research, we set up a resting place to demonstrate the effect of elements and placement in order to obtain knowledge for appropriately managing and utilizing such low use open public spaces. The survey means analyzed the presence/absence of the attraction/retention degree based on the cross-sectional traffic volume by video analysis and a hearing questionnaire survey for the users of the resting place. From the results, we have found that placement methods and effects that exceed the expectation value of each element, regionality, and attachment, occur by continuing experiments. 展开更多
关键词 PUBLIC open space low USAGE area REST area SOCIAL experiment SPATIAL element.
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青藏高原边缘区地震灾后的经济韧性及恢复效率——以汶川Ms 8.0地震极重灾区为例 认领
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作者 周侃 刘宝印 樊杰 《地理学报:英文版》 SCIE CSCD 2020年第8期1363-1381,共19页
The border areas of the Tibetan Plateau and the neighboring mountainous areashave a high incidence of earthquakes with a magnitude greater than Ms 5.0, as well as havinga dense distribution of geological disasters suc... The border areas of the Tibetan Plateau and the neighboring mountainous areashave a high incidence of earthquakes with a magnitude greater than Ms 5.0, as well as havinga dense distribution of geological disasters such as collapses, landslides, and debris flows.Revealing the post-disaster economic development and recovery process is very importantfor enhancing disaster prevention and response capacity in order to formulate control policiesand recovery methods for post-disaster economic reconstruction based on economic resilience.Using long-term socioeconomic data and the autoregressive integrated moving average(ARIMA) model, this paper calculated the economic resilience index of the areas mostseverely affected by the Wenchuan Earthquake of 2008 and adopted the improved variablereturns to scale (VRS) date envelopment analysis (DEA) model and the Malmquist productivityindex to analyze the efficiency and effect of annual post-disaster recovery. The resultsshow that: (1) the economic resilience index of the areas most severely affected by theWenchuan Earthquake was 0.877. The earthquake resulted in a short-term economic recessionin the affected areas, but the economy returned to pre-quake levels within two years. Inaddition, the industrial economy was less resilient than agriculture and the service industry. (2)The comprehensive economic recovery efficiency of the disaster-stricken area in the yearfollowing the disaster was 0.603. The comprehensive efficiency, the pure technical efficiency,and the scale efficiency of the plain and hilly areas were significantly greater than those of theplateau and mountain areas. (3) The annual fluctuation in total factor productivity (TFP) followingthe disaster was considerable, and the economic recovery efficiency decreased significantly,resulting in a short-term economic recession. The TFP index returned to steadystate following decreases of 33.7% and 15.2%, respectively, in the two years following thedisaster. (4) The significant decrease in the post-disaster recovery efficiency 展开更多
关键词 economic resilience recovery efficiency Malmquist productivity index post-disaster reconstruction area Wenchuan Earthquake border areas of the Tibetan Plateau
Assessment of the Protected Areas Strategy in Togo under Sustainable Management: The Case Study of Oti-Keran, Togodo, and Abdoulaye Faunal Reserve 认领
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作者 Kossi Fandjinou Kebin Zhang +5 位作者 Fousseni Folega Beckline Mukete Xiaohui Yang Kperkouma Wala Koffi Akpagana Eve Bohnett 《生态学期刊(英文)》 2020年第4期141-159,共19页
This study aims to identify the drivers of environmental degradation due to the dependency of surrounding residents on three protected areas in Togo, Africa (Oti-Keran, Togodo, and Abdoulaye national parks (abbr. OTA ... This study aims to identify the drivers of environmental degradation due to the dependency of surrounding residents on three protected areas in Togo, Africa (Oti-Keran, Togodo, and Abdoulaye national parks (abbr. OTA national parks)). Surveys of villagers conducted in and around the OTA national parks added to data downloaded from Indexmundi data portal. National-level trend analysis results indicated: 1) the number of terrestrial protected areas showed an upward trend, while savannah and forest cover showed alarming decrease trends. 2) At the local level, supplying socio-economic needs in the three selected protected areas directly resulted in biodiversity degradation through animal grazing, hunting and farming. 3) Over 70% of the respondent’s livelihoods consisted of farming and related dependencies on the protected areas for timber and non-timber forest products and income despite the protected status hold by these classified areas. 4) The OTA national parks have been experiencing an increase of anthropogenic pressure such as uncontrolled tree logging and hunting, which seriously impacts animal and vegetation biodiversity. 5) Policymakers should invest more resources in implementing an integrated management system based not only on a holistic vision of the PA that includes participatory management but also accounts for multi-dimensional principles to enable anthropogenic activities in and around the protected areas to satisfy sustainable development requirements. 展开更多
关键词 Classified Area MULTI-DIMENSIONAL PRINCIPLE Viable STRATEGY Approach
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Spatial-temporal Heterogeneity of Green Development Efficiency and Its Influencing Factors in Growing Metropolitan Area: A Case Study for the Xuzhou Metropolitan Area 认领
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作者 QIU Fangdao CHEN Yang +3 位作者 TAN Juntao LIU Jibin ZHENG Ziyan ZHANG Xinlin 《中国地理科学:英文版》 SCIE CSCD 2020年第2期352-365,共14页
This study analyzed the spatial-temporal heterogeneity of green development efficiency and its influencing factors in the growing Xuzhou Metropolitan Area for the period 2000–2015.The slacks-based measure(SBM)model,s... This study analyzed the spatial-temporal heterogeneity of green development efficiency and its influencing factors in the growing Xuzhou Metropolitan Area for the period 2000–2015.The slacks-based measure(SBM)model,spatial autocorrelation,and the geographically weighted regression(GWR)model were used to conduct the analysis.The conclusions were as follows:first,the overall efficiency of green development of the Xuzhou Metropolitan Area decreased,the regional differences and spatial agglomeration shrunk and differences within the region were the main contributors to the regional differences of green development efficiency.Second,the counties with high-efficiency green development were distributed along the coast,and along the routes of the Beijing-Shanghai and the Eastern Longhai railways.A developing axis of the high-efficiency counties was the main feature of the spatial pattern for green development efficiency.Third,regarding spatial correlation and green development efficiency,the High-High type counties in the Xuzhou Metropolitan Area formed a centralized distribution corridor along the inter-provincial border areas of Henan and Jiangsu,whereas the Low-Low type counties were concentrated in the external,marginal parts of the metropolitan area.Fourth,the major factors(ranked in decreasing order of impact)influencing green development efficiency were innovation,government regulations,the economic development level,energy consumption,and industrial structure.These factors exerted their influence to varying extents;the influence of the same factor had different effects in different regions and obvious spatial differences were observed for the different regions. 展开更多
关键词 GROWING METROPOLITAN area green development EFFICIENCY spatial and TEMPORAL HETEROGENEITY influential factors XUZHOU METROPOLITAN Area China
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LiDAR Helps Differentiate Stand Health and Productivity Levels within a Northern Hardwood Forest 认领
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作者 Christopher F. Hansen Paul G. Schaberg +2 位作者 Allan M. Strong Shelly A. Rayback Gary J. Hawley 《林学期刊(英文)》 2020年第1期66-80,共15页
Light detection and ranging (LiDAR) data can provide detailed information about three-dimensional forest structure. However, links between forest structure and tree function have not been fully evaluated using LiDAR. ... Light detection and ranging (LiDAR) data can provide detailed information about three-dimensional forest structure. However, links between forest structure and tree function have not been fully evaluated using LiDAR. We assessed the relationship of LiDAR-derived structural categories to tree health and productivity on 36 hardwood plots at the Hubbard Brook Experimental Forest, New Hampshire, USA. We established nine plot replicates for each of four LiDAR-based vegetation categories: 1) high crown and high understory closure;2) high crown and low understory closure;3) low crown and high understory closure;and 4) low crown and low understory closure. Ground-based measures of canopy structure, site, stand and individual tree measures were collected on plots during summer 2012. Significant differences among LiDAR categories were found for several response variables. Lower basal area increment for sugar maple (Acer saccharum), decreased foliar nutrition for yellow birch (Betula alleghaniensis), and lower overall crown health were all associated with high understory closure provided that overstory closure was also high. These results suggest that LiDAR measures can be used to assess competitive interactions between overstory and understory vegetation, and that LiDAR shows promise for identifying stands with reduced health and productivity due to factors such as competition or overstocking. 展开更多
关键词 BASAL Area INCREMENT Crown Health FOLIAR Nutrition TREE Function TREE Mortality
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粤港澳大湾区规划治理与协作策略 认领
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作者 姚江春 池葆春 +3 位作者 刘中毅 He Donghua Zeng Zheng Li Caige 《城市规划:英文版》 CSCD 2020年第2期24-34,共11页
The development of the Guangdong-Hong Kong-Macao Greater Bay Area is an important part of China’s national strategy in the new era.This paper reviews the process of cross-border planning collaboration in this area,fr... The development of the Guangdong-Hong Kong-Macao Greater Bay Area is an important part of China’s national strategy in the new era.This paper reviews the process of cross-border planning collaboration in this area,from functional division to institutional coordination.However,this process is still constrained by problems such as having few platforms and channels of collaboration,too much reliance on the provincial government,limited measures of collaboration,and weak coordination on the issues concerning core interests.It argues that the orientation should be building an open collaboration framework with multi-party participation and the specific strategies should include establishing a multi-level and multi-party planning collaboration framework,promoting the planning integration of three metropolitan areas,co-building a unified international quality life circle,promoting the co-building and co-sharing of strategic areas,and exploring diversified measures of planning collaboration. 展开更多
关键词 Guangdong-Hong Kong-Macao Greater Bay Area planning collaboration planning governance high quality life circle strategic area
Discussion of Construction of Hainan International Tourism Island and Psychological Health of Tourism Area Residents 认领
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作者 Duoyu Wu Chunru Wang +1 位作者 Chenyun Xu Guo Min 《护理学期刊(英文)》 2020年第4期439-448,共10页
In the ongoing construction of an international tourism island in Hainan, China, the research on the mental health of the residents in the tourism destination is one of the main contents of the research on tourism dev... In the ongoing construction of an international tourism island in Hainan, China, the research on the mental health of the residents in the tourism destination is one of the main contents of the research on tourism development. Tourism area is the cell of Hainan International Tourism Island. The mental health service of the residents in the tourism area is an important part of the health work construction of the international tourism island and the basic way to realize the health care for everyone. Nowadays, people’s demand for mental health services is far greater than the current supply. In view of the current situation of the limited mental health services provided, we put forward higher requirements and directions for the future development of mental health services in tourist areas. It is planned to carry out the first large-scale publicity and education on mental health of residents in Hainan tourism area in China, and evaluate the effect;carry out a large-scale investigation on mental health of residents in the tourism area, and carry out professional intervention and treatment for patients with mental diseases. Finally, the mental health service network and service institutions covering the tourism areas of Hainan Province were established to provide scientific support for the harmonious and healthy development of the international tourism island in Hainan Province. 展开更多
关键词 HAINAN International TOURISM ISLAND PSYCHOLOGICAL HEALTH TOURISM Area
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Study of the Dispersive Component of the Surface Energy of Polylactides by Inverse Gas Chromatography at Infinite Dilution 认领
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作者 Carla Zarazir Mohamad Rajab +3 位作者 Houssam Obeid Joumana Toufaily Imad Toufeili Tayssir Hamieh 《美国分析化学(英文)》 2020年第3期129-136,共8页
Inverse gas chromatography at infinite dilution is a powerful technique that can be advantageously used to characterize the surface physicochemical properties of solid substrates as oxides and polymers in both forms o... Inverse gas chromatography at infinite dilution is a powerful technique that can be advantageously used to characterize the surface physicochemical properties of solid substrates as oxides and polymers in both forms of powder or fibres. In the case of polymer, this technique can be used to determine the second order transition phenomena temperatures. This paper was devoted to the determination of the glass transition temperature of polylactide polymer. The dispersive component of the surface energy ?of polylactides was determined by inverse gas chromatography at infinite dilution. Various theoretical models were used to deduce the dispersive component of the surface energy of the solid substrates. These models are based on the calculation of the molecular areas of adsorbed molecules on the polymer surface: geometrical model, cylindrical molecular model, liquid density model, BET method, Kiselev results and the two-dimensional Van der Waals and Redlich-Kwong equations. The curves relative to the variation of as a function of the temperature showed a specific graph with a maximum value of ?at a certain particular temperature characteristic to the investigated polylactide polymer. In fact, the maxima of ?indicated the presence of glass transition temperature Tg of polylactide whatever the molecular model used. This study showed a glass transition temperature equal to 64°C confirming that obtained by other studies. 展开更多
关键词 Adsorption SURFACE Area SURFACE Energy RETENTION Volume N-ALKANES EQUATIONS of State
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