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Production Chain Length and PPI-CPI Divergence:Analysis Based on the Global Input-output Price Model
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作者 Ni Hongfu Yan Bingqian Wu Liyuan 《China Economist》 2024年第3期49-69,共21页
Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production ... Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production chains.The question is how the changing length of production chains will affect CPI and PPI,as well as CPI-PPI correlation?By constructing a global input-output price model,this paper offers a theoretical discussion on the impact of production chain length on the CPI-PPI divergence.Our findings suggest that the price shock of international bulk commodities has a greater impact on China’s PPI than that on CPI.The effects on both China’s PPI and CPI estimated by using the single-country input-output model are higher than the results estimated with the global input-output model.However,the difference between CPI and PPI variations estimated with the global input-output model is greater than the result estimated with the single-country input-output model,which supports the view that the lengthening of production chains,especially international production chains,leads to a divergence between CPI and PPI.Empirical results based on cross-national panel data also suggest that the lengthening of production chains has reduced the CPI-PPI correlation for countries,i.e.the lengthening of production chains has increased the PPI-CPI divergence.That is to say,policymakers should target not just CPI in maintaining price stability,but instead focus on the stability of both PPI and CPI.Efforts can be made to proactively adjust the price index system,and formulate the industrial chain price index. 展开更多
关键词 Global value chains length of production chains consumer price index producer price index
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Promoting grain production through high-standard farmland construction:Evidence in China
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作者 Shuai Hao Guogang Wang +4 位作者 Yantao Yang Sicheng Zhao Shengnan Huang Liping Liu Huanhuan Zhang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期324-335,共12页
Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capa... Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capacity.Based on panel data from 31 sample provinces,autonomous regions,and municipalities in China from 2005–2017,this study explored the impact of HSFC on grain yield using the difference-in-differences(DID)method.The results showed that HSFC significantly increased total grain production,which is robust to various checks.HSFC increased grain yield through three potential mechanisms.First,it could increase the grain replanting index.Second,it could effectively reduce yield loss due to droughts and floods.Last,HSFC could strengthen the cultivated land by renovating the low-and medium-yielding fields.Heterogeneity analysis found that the HSFC farmland showed a significant increase in grain yield only in the main grain-producing areas and balanced areas.In addition,HSFC significantly increased the yields of rice,wheat,and maize while leading to a reduction in soybean yields.The findings suggest the government should continue to promote HSFC,improve construction standards,and strictly control the“non-agriculturalization”and“non-coordination”of farmland to increase grain production further.At the same time,market mechanisms should be used to incentivize soybean farming,improve returns and stabilize soybean yields. 展开更多
关键词 high-standard farmland farmland construction food security food production area DIFFERENCE-IN-DIFFERENCES
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A Comparative Study of Different Methods on Quality Assessment of Soil Environment Polluted by Zinc in Agricultural Production Areas——A Case Study in Shulan City of Jilin Province
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作者 李润林 姚艳敏 于士凯 《Agricultural Science & Technology》 CAS 2012年第10期2191-2196,共6页
[Objective] The aim was to explore evaluated precision on quality of soil environment polluted with zinc in agricultural production areas and to provide references for verification of production area.[Method] In Shula... [Objective] The aim was to explore evaluated precision on quality of soil environment polluted with zinc in agricultural production areas and to provide references for verification of production area.[Method] In Shulan City in Jilin Province,soils were sampled and analyzed in a laboratory using single-factor pollution index and GIS based spatial interpolation.The quality of environment polluted with zinc was assessed and related methods were compared according to Environment Quality Standard of Green Food Production Area.[Result] Spatial interpolation of zinc in soils based on GIS proved more precise than traditional methods;cokriging method with co-factors was higher in precision than common cokriging;cokriging method with zinc and organic matter was higher in precision than cokriging with zinc alone.[Conclusion] Quality assessment on environment polluted with zinc based on GIS interpolation is more scientific and reasonable than traditional methods. 展开更多
关键词 Agricultural production area Soil Environment Quality Assessment COKRIGING Ordinary kriging
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Employment and development levels in rural areas of the Russian Federation
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作者 Guzel SALIMOVA Gulnara NIGMATULLINA +2 位作者 Gamir HABIROV Alisa ABLEEVA Rasul GUSMANOV 《Regional Sustainability》 2024年第3期124-134,共11页
The development of agro-industrial complex is important for ensuring national food security and national health.The development of rural areas is subject to the development of agriculture and local infrastructure,as w... The development of agro-industrial complex is important for ensuring national food security and national health.The development of rural areas is subject to the development of agriculture and local infrastructure,as well as the availability of various services.This study selected 15 indicators in 2021 to analyze the employment and development levels in rural areas of 71 regions of the Russian Federation using the analytical grouping method.The results indicated that 20 regions(Group 1)had the highest percentage of rural population(33.10%).The percentage of population engaged in agriculture had the highest value(12.40%)in 31 regions(Group 2).Moreover,20 regions(Group 3)had the highest investments in fixed assets at the expense of municipal budget(11.80 USD/person).Increasing the investments in fixed assets carried out from the budget of the municipality can improve the employment level in rural areas.Then,we used cluster analysis to divide 14 regions of the Volga Federal District in the Russian Federation into 3 clusters.Cluster 1 covered Kirov Region and Republic of Mari El;Cluster 2 included Ulyanovsk Region,Saratov Region,Nizhny Novgorod Region,Perm Territory,Orenburg Region,Chuvash Region,and Republic of Mordovia;and Cluster 3 contained Republic of Tatarstan,Samara Region,Udmurtian Republic,Penza Region,and Republic of Bashkortostan.Results indicated that the 2 regions of Cluster 1 need to increase the availability of resources and natural gas and improve the investment attractiveness of rural areas.The 7 regions of Cluster 2 needed to develop infrastructure,public services,and agricultural production.We found the highest employment level in rural areas,the largest investments in fixed assets at the expense of municipal budget,the largest residential building area per 10,000 persons,and the largest individual residential building area in the 5 regions of Cluster 3.This study makes it possible to draw up a comprehensive regional development program and proves the need for the development of rural areas,which is especially important for the sustainable development of the Russian Federation. 展开更多
关键词 Rural areas Employment level Labor productivity Investments in fixed assets Sustainable Development Goal(SDG) Russian Federation
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Agricultural Production Structure Optimization: A Case Study of Major Grain Producing Areas, China 被引量:4
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作者 LU Sha-sha LIU Yan-sui +1 位作者 LONG Hua-lou GUAN Xing-liang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第1期184-197,共14页
A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors (e.g., eco... A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors (e.g., eco-social benefit maximization, food security, employment stability and ecosystem balance). In this study, an interval-probabilistic agricultural production structure optimization model (IPAPSOM) is formulated for tackling uncertainty presented as discrete intervals and/or probability distribution. The developed model improves upon the existing probabilistic programming and inexact optimization approaches. The IPAPSOM considers not only food security policy constraints, but also involves rural households’income increase and eco-environmental conversation, which can effectively reflect various interrelations among different aspects in an agricultural production structure optimization system. Moreover, it can also help examine the reliability of satisfying (or risk of violating) system constraints under uncertainty. The model is applied to a real case of long-term agricultural production structure optimization in Dancheng County, which is located in Henan Province of Central China as one of the major grain producing areas. Interval solutions associated with different risk levels of constraint violation are obtained. The results are useful for generating a range of decision alternatives under various system benefit conditions, and thus helping decision makers to identify the desired agricultural production structure optimization strategy under uncertainty. 展开更多
关键词 major grain producing areas agricultural production structure optimization interval-probabilistic programming food security farmers’income increase China
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A Study on Japanese Traditional Rice Production Technique in Warm Areas and Its Modern Ecological Value
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作者 Lei YE Lulu QIAN 《Asian Agricultural Research》 2019年第1期38-41,共4页
Japanese traditional rice production technique features " sparse seeding,long cultivation,scattered planting and limited transplanting",and scientific rice production methods of deep plowing,fertilization,we... Japanese traditional rice production technique features " sparse seeding,long cultivation,scattered planting and limited transplanting",and scientific rice production methods of deep plowing,fertilization,weeding,irrigation and drainage are employed.This technique has reversed the common practice of " dense seeding and planting" in rice paddies and changed the history of growing rice spikes purely out of stems,thus enabling stable and high yields of several tillering grain crops including rice.The technique can provide a useful reference for developing modern rice production in warm areas. 展开更多
关键词 Japan TRADITIONAL rice production TECHNIQUE in WARM areas SPARSE SEEDING and PLANTING Nougyou Zitoku
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Measurement of Grain Production Efficiency in Main Grain-producing Areas and Analysis of Inter-provincial Differences--A Study Based on Super-SBM Model and Malmquist Index
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作者 Qi Heng Su Jing-yan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2022年第2期86-96,共11页
China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-p... China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-producing areas has become the fundamental way to strengthen the grain production capacity and improve the national food security capability,and to improve the efficiency of grain production in major grain-producing areas requires empirical support.This paper used the Super SBM model and the Malmquist index to measure the grain production efficiency of the main grain-producing areas from 2001 to 2020 from both static and dynamic perspectives,and compared the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas.The results showed that from 2001 to 2020,the grain production in the main grain-producing areas was in a relatively ineffective state,and the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas were obvious.The order of grain production efficiency in different soil types was black soil region>red-yellow soil region>paddy soil region>fluvo-aquic soil region,and the order of grain production efficiency of the provinces(autonomous regions)in the main grain-producing areas was Jilin>Heilongjiang>Inner Mongolia>Jiangxi>Hunan>Sichuan>Hubei>Jiangsu>Liaoning>Henan>Anhui>Shandong>Hebei.From 2001 to 2020,the total factor productivity of grain in the main grain-producing areas increased,but due to the trade-off between the technological progress and the growth of technical efficiency,the increase in the total factor productivity of grain in the main grain-producing areas was small,and the growth mainly came from the increase of input factors in this period.The total factor productivity of grain in Hebei,Heilongjiang,Liaoning,Jilin,Inner Mongolia,Shandong,Jiangsu,Henan and Anhui increased,but the increase was small,while the total factor productivity of grain in Jiangxi,Sichuan,Hunan and Hubei provinces declined. 展开更多
关键词 main grain-producing area grain production efficiency inter-provincial difference
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Content Determination of Total Flavonoids in Tetracera asiatica from 10 Different Production Areas in Guangxi
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作者 Fangfang DA Zhonghua DAI Hua ZHU 《Medicinal Plant》 2017年第5期11-13,共3页
[Objectives] To determine the content of total flavonoids in Tetracera asiatica from different production areas in Guangxi and provide a basis for improving the quality standards of crude drug. [Methods] Using 50% eth... [Objectives] To determine the content of total flavonoids in Tetracera asiatica from different production areas in Guangxi and provide a basis for improving the quality standards of crude drug. [Methods] Using 50% ethanol as extractor,NaNO_2-Al(NO_3)_3-NaOH as chromogenic system and rutin as the reference substance,the content of total flavonoids from the crude drug was determined. [Results] A method for determining the content of total flavonoids was established,the content of total flavonoids was 11.35-21.35 mg·g^(-1),and the average content was 17.64 mg·g^(-1). [Conclusions] The method had high repeatability and stability,and the method was simple,rapid and sensitive and suitable for quantitative analysis. 展开更多
关键词 Tetracera asiatica TOTAL FLAVONOIDS CONTENT determination GUANGXI DIFFERENT production areas
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IMPLICATION OF CLIMATE CHANGE FOR AGRICULTURAL PRODUCTION IN EASTERN AREAS OF CHINA
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作者 王馥棠 《中国气象科学研究院年报》 1995年第0期17-24,共8页
IMPLICATIONOFCLIMATECHANGEFORAGRICULTURALPRODUCTIONINEASTERNAREASOFCHINAWangFutang(王馥棠)IMPLICATIONOFCLIMATEC... IMPLICATIONOFCLIMATECHANGEFORAGRICULTURALPRODUCTIONINEASTERNAREASOFCHINAWangFutang(王馥棠)IMPLICATIONOFCLIMATECHANGEFORAGRICULTU... 展开更多
关键词 馥棠 production EASTERN CLIMATE OF CHANGE areas AGRICULTURAL
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Climate Characteristics in Three Gorges Reservoir Area after Water Storage and Its Impact on the Production Potential
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作者 钟海玲 高荣 杨霞 《Meteorological and Environmental Research》 CAS 2010年第2期53-56,共4页
Based on the meteorological data from 33 stations of Three Gorges Reservoir from 1960 to 2008,climate yield of rice,corn and winter wheat and the changes of climatic potential productivity after water storage in Three... Based on the meteorological data from 33 stations of Three Gorges Reservoir from 1960 to 2008,climate yield of rice,corn and winter wheat and the changes of climatic potential productivity after water storage in Three Gorges Reservoir were calculated by the dynamic statistic model of crop growth.The results showed that the temperature in Three Gorges Reservoir was fluctuant decreased before late 1980s,and warmed rapidly after the late 1980s.The precipitation had little change before the late 1990s and had a slight decrease after the late 1990s.Sunshine hours were more in 1960s and 1970s,and then it changed little after 1980s.After water storage,the temperature increased in Three Gorges Reservoir as a whole.The precipitation decreased in the south of Three Gorges Reservoir,while it increased in the northwest of Three Gorges Reservoir.The sunshine hours were reduced except that in the vicinity of Dianjiang.After water storage,climatic potential productivity of rice decreased in the northwest and the northeast,while it increased in the south of Three Gorges Reservoir.The climatic potential productivity of corn decreased in the northeast and the southwest,but increased in the rest of Three Gorges Reservoir.The climatic potential productivity of winter wheat increased almost in total. 展开更多
关键词 Three Gorges Reservoir area Water storage Climatic potential productivity CHANGE China
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Influential Factors of Water Productivity of Maize in Oasis of Arid Areas——A Case Study of Linze County
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作者 胡广录 张济世 樊立娟 《Agricultural Science & Technology》 CAS 2012年第9期1854-1858,共5页
[Objective] The aim was to research influential factors of water productivity of maize in oasis in arid areas. [Method] In middle reach of Heihe River in Linze County of Zhangye City, maize, a major crop in irrigated ... [Objective] The aim was to research influential factors of water productivity of maize in oasis in arid areas. [Method] In middle reach of Heihe River in Linze County of Zhangye City, maize, a major crop in irrigated area in the oasis, was studied and nine influential factors were chosen through grey relation analysis. [Result] According to grey relation analysis, top five factors influencing water produc- tivity of maize during 1995-2009 were as follows: applied quantity of chemical fertil- izers〉labour input〉seeds〉mulch amount〉pesticide amount, which indicated that controllable factors, instead of uncontrollable ones, dominate in influence of water productivity of maize in oasis in arid areas. [Conclusion] With water resource limited, investment of controllable factors in high-efficient agricultural production should be the major strategy to improve water productivity of maize in oasis of arid areas. 展开更多
关键词 MAIZE Water productivity Influential factors Gray relation analysis Irri-gated areas in oasis
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Production Characteristics and the Control Factors of Surface Wells for Relieved Methane Drainage in the Huainan Mining Area 被引量:6
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作者 XU Hongjie SANG Shuxun +1 位作者 FANG Liangcai HUANG Huazhou 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第4期932-941,共10页
Based on the production data of a large number of surface drainage wells in the Huainan mining area,the present study shows that four types of typical production characteristics for relieved methane wells are recogniz... Based on the production data of a large number of surface drainage wells in the Huainan mining area,the present study shows that four types of typical production characteristics for relieved methane wells are recognized,of which the stable type for production and gas concentration is the most dominate,as determined by a comprehensive study on the volume and concentration of drained gases, as well as the stress changes of rocks influenced by mining.Some influence factors for the productive differences of the drainage wells were also been discussed.The results indicate that protective coal-seam mining has a significant effect on overlying strata,which promotes the development of pores and fractures of coal reservoirs for methane desorption and migration;however,the production and the stability of drainage wells are affected by deformation and damage of the overlying strata.The second distribution of strata stress is caused by mining engineering,and if the stress load is larger than the carrying capacity of the extraction well,the gas production would be influenced by the drainage well that has been damaged by rock movement.Furthermore,the case damage occurs first in the weak, lithologic interface by its special mechanical properties.The stability of drainage wells and the production status are also influenced by the different drilling techniques,uneven distribution of gas concentration,and combination of gob gas and methane from the protected layer. 展开更多
关键词 relieved methane surface drainage well Huainan mining area production characteristic control factor
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Distribution of gas hydrate reservoir in the first production test region of the Shenhu area,South China Sea 被引量:19
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作者 Ru-wei Zhang Jing-an Lu +5 位作者 Pen-fei Wen Zeng-gui Kuang Bao-jin Zhang Hua Xue Yun-xia Xu Xi Chen 《China Geology》 2018年第4期493-504,共12页
In May and July of 2017,China Geological Survey (CGS),and Guangzhou Marine Geological Survey (GMGS)carried out a production test of gas hydrate in the Shenhu area of the South China Sea and acquired a breakthrough of ... In May and July of 2017,China Geological Survey (CGS),and Guangzhou Marine Geological Survey (GMGS)carried out a production test of gas hydrate in the Shenhu area of the South China Sea and acquired a breakthrough of two months continuous gas production and nearly 3.1×10^5 m^3 of production. The gas hydrate reservoir in the Shenhu area of China,is mainly composed of fine-grained clay silt with low permeability,and very difficult for exploitation,which is very different from those discovered in the USA,and Canada (both are conglomerate),Japan (generally, coarse sand)and India (fracture-filled gas hydrate).Based on 3D seismic data preserved-amplitude processing and fine imaging,combined with logging-while-drilling (LWD)and core analysis data,this paper discusses the identification and reservoir characterization of gas hydrate orebodies in the Shenhu production test area.We also describe the distribution characteristics of the gas hydrate deposits and provided reliable data support for the optimization of the production well location.Through BSR feature recognition,seismic attribute analysis, model based seismic inversion and gas hydrate reservoir characterization,this paper describes two relatively independent gas hydrate orebodies in the Shenhu area,which are distributed in the north-south strip and tend to be thicker in the middle and thinner at the edge.The effective thickness of one orebody is bigger but the distribution area is relatively small.The model calculation results show that the distribution area of the gas hydrate orebody controlled by W 18/W 19 is about 11.24 km^2,with an average thickness of 19 m and a maximum thickness of 39 m,and the distribution area of the gas hydrate orebody controlled by W11/W17 is about 6.42 km^2,with an average thickness of 26 m and a maximum thickness of 90 m. 展开更多
关键词 Shenhu area GAS HYDRATE production test RESERVOIR distnbution
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Variation Characteristics of Hydrothermal Resources Effectiveness Under the Background of Climate Change in Southern Rice Production Area of China 被引量:2
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作者 YE Qing YANG Xiao-guang +2 位作者 DAI Shu-wei LI Yong GUO Jian-ping 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第12期2260-2279,共20页
The spatiotemporal characteristics of hydrothermal resources in southern rice production area of China have changed under the background of climate change,and this change would affect the effectiveness of hydrothermal... The spatiotemporal characteristics of hydrothermal resources in southern rice production area of China have changed under the background of climate change,and this change would affect the effectiveness of hydrothermal resources during local rice growing period.According to the cropping system subdivision in southern rice production area of China during 1980s,this study used climate data from 254 meteorological stations and phonological data from 168 agricultural observation stations in the south of China,and adopted 6 international evaluation indices about the effectiveness of hydrothermal resources to analyze the temporal and spatial characteristics of hydrothermal resources during the growing period of single cropping rice system and double cropping rice system for 16 planting zones in the whole study area.The results showed that:in southern rice production area of China,the effectiveness of thermal resources of single cropping rice area(SCRA) was less than that of double cropping rice area(DCRA),whereas the effectiveness of thermal resources of both SARA and DCRA showed a decreasing trend.The index value of effective precipitation satisfaction of SCRA was higher than that of DCRA,nevertheless the index value of effective precipitation satisfaction of both SCRA and DCRA showed a decreasing trend.There was a significant linear relationship between effective thermal resource and water demand,likely water demand increased by 18 mm with every 100°C d increase of effective heat.Effective precipitation satisfaction index(EPSI) showed a negative correlation with effective heat,yet showed a positive correlation with effective precipitation.EPSI reduced by 1% when effective heat resource increased by 125°C d.This study could provide insights for policy makers,land managers or farmers to improve water and heat resource uses and rationally arrange rice production activities under global climate change condition. 展开更多
关键词 climate change rice production area effectiveness of hydrothermal resources spatiotemporal characteristics
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Spatiotemporal changes of gross primary productivity and its response to drought in the Mongolian Plateau under climate change 被引量:1
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作者 ZHAO Xuqin LUO Min +3 位作者 MENG Fanhao SA Chula BAO Shanhu BAO Yuhai 《Journal of Arid Land》 SCIE CSCD 2024年第1期46-70,共25页
Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation... Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate change.In this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during 1982-2018.The main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%area.Specifically,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered well.Warming aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central regions.Notably,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were significant.Climate warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to drought.Additionally,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude increased.The cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 months.The findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas. 展开更多
关键词 gross primary productivity(GPP) climate change warming aridification areas drought sensitivity cumulative effect duration(CED) Mongolian Plateau
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Identifying Spatial Heterogeneity in the Effects of High-Tech Firm Density on Housing Prices:Evidence from Guangdong-Hong Kong-Macao Greater Bay Area,China
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作者 WANG Yang WU Kangmin +2 位作者 ZHANG Hong’ou LIU Yi YUE Xiaoli 《Chinese Geographical Science》 SCIE CSCD 2023年第2期233-249,共17页
Innovation capitalization is a new concept in innovation geography research.Extant research on a city scale has proven that innovation is an important factor affecting housing prices and verified that innovation has a... Innovation capitalization is a new concept in innovation geography research.Extant research on a city scale has proven that innovation is an important factor affecting housing prices and verified that innovation has a capitalization effect.However,few studies investigate the spatial heterogeneity of innovation capitalization.Thus,case verification at the urban agglomeration scale is needed.Therefore,this study proposes a theoretical framework for the spatial heterogeneity of innovation capitalization at the urban agglomeration scale.Examining the Guangdong-Hong Kong-Macao Greater Bay Area(GHMGBA),China as a case study,the study investigated the spatial heterogeneity of the influence of high-tech firms,representing innovation,on housing prices.This work verified the spatial heterogeneity of innovation capitalization.The study constructed a data set influencing housing prices,comprising 11 factors in 5 categories(high-tech firms,convenience of living facilities,built environment,the natural environment,and the fundamentals of the districts)for 419 subdistricts in the GHMGBA.On the global scale,the study finds that high-tech firms have a significant and positive influence on housing prices,with the housing price increasing by 0.0156%when high-tech firm density increases by 1%.Furthermore,a semi-geographically weighted regression(SGWR)analysis shows that the influence of high-tech firms on housing prices has spatial heterogeneity.The areas where high-tech firms have a significant and positive influence on housing prices are mainly in the GuangzhouFoshan metropolitan area,western Shenzhen-Dongguan,north-central Zhongshan-Nansha district,and Guangzhou—all areas with densely distributed high-tech firms.These results confirm the spatial heterogeneity of innovation capitalization and the need for further discussion of its scale and spatial limitations.The study offers implications for relevant GHMGBA administrative authorities for spatially differentiated development strategies and housing policies that consider the role of innovation in successful urban development. 展开更多
关键词 innovation capitalization high-tech firms housing prices spatial heterogeneity semi-geographically weighted regression(SGWR) Guangdong-Hong Kong-Macao Greater Bay area(GHMGBA)
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Application of the monitoring and early warning system for internal solitary waves:Take the second natural gas hydrates production test in the South China Sea as an example
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作者 Dan-yi Su Bin-bin Guo +5 位作者 Qian-yong Liang Chu-jin Liang Fei-long Lin Su-meng Jiang Yi-fei Dong Xue-min Wu 《China Geology》 CAS CSCD 2023年第4期676-684,共9页
Internal solitary waves(ISWs) contain great energy and have the characteristics of emergency and concealment. To avoid their damage to offshore engineering, a new generation of monitoring and early warning system for ... Internal solitary waves(ISWs) contain great energy and have the characteristics of emergency and concealment. To avoid their damage to offshore engineering, a new generation of monitoring and early warning system for ISWs was developed using technologies of double buoys monitoring, intelligent realtime data transmission, and automatic software identification. The system was applied to the second natural gas hydrates(NGHs) production test in the Shenhu Area, South China Sea(SCS) and successfully provided the early warning of ISWs for 173 days(from October 2019 to April 2020). The abrupt changes in the thrust force of the drilling platform under the attack of ISWs were consistent with the early warning information, proving the reliability of this system. A total of 93 ISWs were detected around the drilling platform. Most of them occurred during the spring tides in October–December 2019 and April 2020, while few of them occurred in winter. As suggested by the theoretical model, the full-depth structure of ISWs was a typical current profile of mode-1, and the velocities of wave-induced currents can reach 80 cm/s and30 cm/s, respectively, in the upper ocean and near the seabed. The ISWs may be primarily generated from the interactions between the topography and semidiurnal tides in the Luzon Strait, and then propagate westward to the drilling platform. This study could serve as an important reference for the early warning of ISWs for offshore engineering construction in the future. 展开更多
关键词 Internal solitary wave Early warning Offshore engineering Drilling platform Natural gas hydrates production test Shenhu area South China Sea
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Secondary Production of Macrobenthos in Mangrove Area of Tong'an Bay,China 被引量:2
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作者 ZHOU Xiping CAI Lizhe 《Journal of Ocean University of China》 SCIE CAS 2010年第2期151-156,共6页
Studies on secondary production lead to a better understanding of the functions of the macrobenthic ecosystem.Basedon the macrobenthic data obtained at 6 sampling stations from April 2006 to January 2007,Brey's(19... Studies on secondary production lead to a better understanding of the functions of the macrobenthic ecosystem.Basedon the macrobenthic data obtained at 6 sampling stations from April 2006 to January 2007,Brey's(1990)empirical formula wasapplied to calculate the secondary production of macrobenthos in the mangrove area of Tong'an Bay.The results showed that themean annual secondary production of macrobenthos was 13.24 gAFDWm-2-a-1.The mean secondary production in the mangrovehabitat was 12.22 gAFDWm-2-a-1,lower than that in the non-mangrove habitat,which was 15.29 gAFDWm-2-a-1.Two possible rea-sons existed for this difference.First,mollusk and crustacean,which contribute more to the secondary production,probably benefitfrom longer inundation period in the non-mangrove habitat.Second,the higher organic matter in the mangrove habitat results in hy-poxia in the bottom sediment,which may decrease the secondary production.The annual mean production-to-biomass(P/B)ratio inTong'an Bay was 1.17,with a ratio of 1.27 in the mangrove habitat and 0.96 in the non-mangrove habitat,which was coincident withthe much higher density of Limnodriloides sp.and Corophium sp.in the mangrove habitat than in the non-mangrove habitat.Themaximum secondary production and P/B ratio of macrobenthos both appeared at sampling station FL2 in April,2006(namelyApril-FL2)with values of 31.38 gAFDWm-2-a-1and 2.20,respectively.The macrobenthic secondary production in Tong'an Bay islower than those in other intertidal studies except that in Haitan Strait,the reason being the different sediment properties.The P/Bratio in Tong'an Bay was the lowest due to the high proportion of crustaceans in the macrobenthic community. 展开更多
关键词 secondary production MACROBENTHOS P/B ratio Tong'an Bay mangrove area
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Lateral bearing characteristics of subsea wellhead assembly in the hydrate trial production engineering
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作者 Jing Zeng Wen-wei Xie +8 位作者 Bei-bei Kou Jing-an Lu Xing-chen Li De-jun Cai Hao-xian Shi Ke-wei Zhang Hua-qing Liu Jin Li Bo Li 《China Geology》 CAS CSCD 2023年第3期455-465,共11页
Conductor and suction anchor are the key equipment providing bearing capacity in the field of deep-water drilling or offshore engineering,which have the advantages of high operation efficiency and short construction p... Conductor and suction anchor are the key equipment providing bearing capacity in the field of deep-water drilling or offshore engineering,which have the advantages of high operation efficiency and short construction period.In order to drill a horizontal well in the shallow hydrate reservoir in the deep water,the suction anchor wellhead assembly is employed to undertake the main vertical bearing capacity in the second round of hydrate trial production project,so as to reduce the conductor running depth and heighten the kick-off point position.However,the deformation law of the deep-water suction anchor wellhead assembly under the moving load of the riser is not clear,and it is necessary to understand the lateral bearing characteristics to guide the design of its structural scheme.Based on 3D solid finite element method,the solid finite element model of the suction anchor wellhead assembly is established.In the model,the seabed soil is divided into seven layers,the contact between the wellhead assembly and the soil is simulated,and the vertical load and bending moment are applied to the wellhead node to simulate the riser movement when working in the deep water.The lateral bearing stability of conventional wellhead assembly and suction anchor wellhead assembly under the influence of wellhead load is discussed.The analysis results show that the bending moment is the main factor affecting the lateral deformation of the wellhead string;the anti-bending performance from increasing the outer conductor diameter is better than that from increasing the conductor wall thickness;for the subsea wellhead,the suction anchor obviously improves the lateral bearing capacity and reduces the lateral deformation.The conduct of the suction anchor wellhead assembly still needs to be lowered to a certain depth that below the maximum disturbed depth to ensure the lateral bearing stability,Thus,a method for the minimum conductor running depth for the suction anchor wellhead assembly is developed.The field implementations show that compared with the first round of hydrate trial production project,the conductor running depth is increased by 9.42 m,and there is no risk of wellhead overturning during the trial production.The method for determining the minimum conductor running depth in this paper is feasible and will still play an important role in the subsequent hydrate exploration and development. 展开更多
关键词 Natural gas hydrate Deep-water Subsea wellhead Suction anchor Wellhead stability 3D solid finite element method Hydrate trial exploration engineering Natural gas hydrate trial production Shenhu area The South China Sea
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Distributed optical fiber acoustic sensor for in situ monitoring of marine natural gas hydrates production for the first time in the Shenhu Area,China 被引量:2
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作者 Xiang-ge He Xue-min Wu +6 位作者 Lei Wang Qian-yong Liang Li-juan Gu Fei Liu Hai-long Lu Yi Zhang Min Zhang 《China Geology》 2022年第2期322-329,共8页
The distributed acoustic sensor(DAS)uses a single optical cable as the sensing unit,which can capture the acoustic and vibration signals along the optical cable in real-time.So it is suitable for monitoring downhole p... The distributed acoustic sensor(DAS)uses a single optical cable as the sensing unit,which can capture the acoustic and vibration signals along the optical cable in real-time.So it is suitable for monitoring downhole production activities in the process of oil and gas development.The authors applied the DAS system in a gas production well in the South China Sea for in situ monitoring of the whole wellbore for the first time and obtained the distributed acoustic signals along the whole wellbore.These signals can clearly distinguish the vertical section,curve section,and horizontal production section.The collected acoustic signal with the frequency of approximately 50 Hz caused by the electric submersible pump exhibit a signal-to-noise ratio higher than 27 dB.By analyzing the acoustic signals in the production section,it can be located the layers with high gas production rates.Once an accurate physical model is built in the future,the gas production profile will be obtained.In addition,the DAS system can track the trajectory of downhole tools in the wellbore to guide the operation.Through the velocity analysis of the typical signals,the type of fluids in the wellbore can be distinguished.The successful application of the system provides a promising whole wellbore acoustic monitoring tool for the production of marine gas hydrate,with a good application prospect. 展开更多
关键词 Gas hydrate production monitoring Optical fiber sensor Distributed acoustic sensor In situ monitoring Fluid type NGHs exploration trial engineering Oil and gas exploration engineering Shenhu area South China Sea
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