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A Study on Theoretical Model and Applied Evaluation of Land Use Performance of High-tech Zone in Urban Fringe: A Case Study in Haidian District, Beijing 被引量:3
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作者 Ban Maosheng Fang Chuanglin Liu Xiaoli 《Chinese Journal of Population,Resources and Environment》 北大核心 2008年第1期91-96,共6页
High-tech industrial zone is an important carrier for constructing innovative cities. It also plays an important role in implementing the national independent innovative strategy. How-ever, most of the high-tech indus... High-tech industrial zone is an important carrier for constructing innovative cities. It also plays an important role in implementing the national independent innovative strategy. How-ever, most of the high-tech industrial zones have many problems in their development process, such as efficiency of land use, weakness of oriented function and lack of land intensive. To solve these problems, the authors of this paper introduced the concept of land use performance and established the theoretical model to assess the land use performance of high-tech industrial zones. The model consists of the following three-dimensional parts: land use benefit, land use efficiency and innovative function. Based on this theory model, an index system which was composed of three secondary indictors, eight tertiary indictors and 37 fourth-grade indictors was set up to evaluate the land use performance of high-tech zone. To avoid the defects of plus model and function model, the authors brought out a three-dimensional evaluation model to examine the index of the land use performance of the high-tech industrial parks, which equals to the evaluation indicator system of land use performance of high-tech zone based on the above research. The authors examined the land use performance of five different high-tech industrial parks in Haidian District, Beijing City. The results indicated that the indicator system per-forms better in the aspect of evaluating land use benefit, land use efficiency and function of the high-tech industrial zone compared with other models. 展开更多
关键词 high-tech industry zone innovative ability land use performance theoretical mode
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A LOCATIONAL COMPARATIVE STUDY ON HIGH-TECH INDUSTRIAL ZONES IN CHINA 被引量:4
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作者 魏心镇 史永辉 《Chinese Geographical Science》 SCIE CSCD 1994年第1期1-7,共7页
There are three ports in this poper.Part I is involved in discussion of threeessential soft factors acting at development of high-tech industry-location,nctworkand comptehensive factors.It strobes the role of brains a... There are three ports in this poper.Part I is involved in discussion of threeessential soft factors acting at development of high-tech industry-location,nctworkand comptehensive factors.It strobes the role of brains and practical capeity inhigh-tech development,clarifying the same importance of qualified personnel networkas information network,elucidating both intemal and external impetus Part II dealswith locatkinal comparison among high-tech industrial zones in Ch;. for which anAnalysis of Hierarchy Process (AHP) method is used. Upe esults, Chinesehigh-tech industrial zones are divided into four grades. The las. p proposes four aspects as implementation measures for high-tech industrial zone in China. 展开更多
关键词 high-tech INDUSTRY ESSENTIAL SOFT FACTOR AHP
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The Role of China's High-Tech Zones in Its Regional Economic Development 被引量:2
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作者 刘瑞明 赵仁杰 《China Economist》 2016年第5期44-56,共13页
National high-tech industrial development zones represent a major strategy of the Chinese government in developing high-tech industries and spurring regional economic growth. The effect of this policy is yet to be pro... National high-tech industrial development zones represent a major strategy of the Chinese government in developing high-tech industries and spurring regional economic growth. The effect of this policy is yet to be proven. Based on the panel data of 283 Chinese cities between 1984 and 2012, this paper investigates the effect of high-tech zones on regional economic development. Empirical results suggest that first, national hightech zones have remarkably enhanced regional GDP and per capita GDP growth, and this conclusion still holds true after multiple rounds of robustness test; second, the economic effect of national high-tech zones is subject to diminishing marginal return and compared with higher-tier cities, lower-tier cities benefited more from the creation of national hightech zones. This paper concludes that national high-tech zones where special policies are experimented and offered not only drive economic development but, if properly distributed across regions, may help reduce regional economic disparities as well. The results of this study provide important implications for the future distribution of national high-tech zones and the creation of other relevant policies. 展开更多
关键词 national high-tech zones regional economic growth difference-in-differences method
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Spatial Pattern Evolution and Industrial Characteristics of Economic and Technological Development Zones and High-tech Industrial Zones in China 被引量:1
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作者 LI Jingxian LIU Qing LI Guicai 《Journal of Landscape Research》 2021年第2期11-16,共6页
Economic and technological development zone and high-tech industrial zone are important types of development zone in China,and there are differences in their connotation and goal setting.In this paper,basic data of na... Economic and technological development zone and high-tech industrial zone are important types of development zone in China,and there are differences in their connotation and goal setting.In this paper,basic data of national and provincial economic and technological development zones and high-tech industrial zones in China were collected and arranged.Kernel density analysis and other GIS spatial analysis techniques were used to analyze the evolution laws of spatial patterns of economic and technological development zones and high-tech industrial zones in cities from 2006 to 2018.First,the agglomeration intensity was compared by measuring the degree of regional agglomeration and dispersion on the two time nodes.Next,kernel density method was used to explore the evolution of the two in the spatial layout and location,and analyze development commonness and difference of economic and technological development zones and high-tech industrial zones.Finally,the trend and reason of spatial evolution of development zones with different leading industries were explored.Research results show that:①the agglomeration degree of layout of high-tech industrial zones is stronger than that of economic and technological development zones,and there are similarities and differences in distribution trend of spatial patterns of the two types of development zones;②the distribution of labor-intensive,capital-intensive and technology-intensive development zones is concentrated at smaller scales and dispersed at larger ones;③although there are differences between the economic and technological development zones and the high-tech industrial zones in the goal,support,structure and function,management system and so on,their spatial development presents a trend of convergence.In the future,when enhancing urban-rural planning and public administration,governments should combine the trend of industrial transformation and upgrading,and optimize spatial layout of development zones by adjusting industrial structure,layout,transportation and land use. 展开更多
关键词 Economic and technological development zone high-tech industrial zone Spatial pattern
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A Study of the Industrial Development in Huazhong Agricultural High-tech Industrial Development Zone
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作者 Yougang ZHANG Shuhui SHAO 《Asian Agricultural Research》 2017年第5期45-47,共3页
This paper illustrates the current situation and problems concerning the industrial structure in Huazhong Agricultural High-tech Industrial Development Zone,and analyzes the internal contradictions that exist in indus... This paper illustrates the current situation and problems concerning the industrial structure in Huazhong Agricultural High-tech Industrial Development Zone,and analyzes the internal contradictions that exist in industry: small-scale land operation has become an inherent obstacle to the industrial development in Agricultural High-tech Zone; farmers are always in a passive position in industrial restructuring optimization; government's policy failures and rent-seeking behaviors have hindered industrial development; the research,popularization and application of agricultural science and technology is not suited to industrial development requirements. Finally,this paper makes the corresponding recommendations for industrial development in Huazhong Agricultural High-tech Industrial Development Zone. 展开更多
关键词 Huazhong Agricultural high-tech Industrial Development zone Industrial development RECOMMENDATIONS
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The Impact of the Establishment of National High-tech Zones on Total Factor Productivity of Chinese Enterprises
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作者 Wang Mingyi Liu Xiaoyu 《China Economist》 2023年第3期68-93,共26页
The National High-tech Zone(NHTZs)is an important strategic platform for cultivating high-tech industries and realizing high-quality economic development in China.Based on the combined data from 2006 to 2014 of the in... The National High-tech Zone(NHTZs)is an important strategic platform for cultivating high-tech industries and realizing high-quality economic development in China.Based on the combined data from 2006 to 2014 of the industrial enterprise database,the customs database,and the China Development Zones Audit and Announcement Catalogue(abbreviated asthe Catalogue),this paper systematically investigates the influence of the construction of NHTZs on enterprise’s total factor productivity(TFP).Results show that NHTZs have a positive impact on the TFP of enterprises in the zone,and this conclusion is still valid after considering endogeneity problems.Furthermore,the above productivity effects of NHTZs are heterogeneous in terms of enterprise ownership,external environment and establishment time,and NHTZs have greater stimulation effects on enterprise productivity after comparing with other types of functional zones.An investigation of the specific mechanisms at play shows that NHTZs promote the TFP of enterprises in the zone through the release of preferential policies,strengthening the“technology spillover effects”of imported intermediate goods,enhancing enterprise’s innovation ability and attracting talent.In addition,based on the decomposition of industry productivity,this paper also investigates the impact of NHTZs on changes in industry productivity and finds that NHTZs promote the overall productivity of specific industries mainly by stimulating the productivity improvement of incumbent enterprises and expanding the market share of high-productivity enterprises.Moreover,the preferential policies of NHTZs do not significantly stimulate high-productivity enterprises to enter the zones,nor do they cause low-productivity enterprises to exit.This research is helpful in objectively evaluating the economic effects of the NHTZs in China and in providing a theoretical basis for its further adjustment. 展开更多
关键词 National high-tech zones(NHTZs) total factor productivity(TFP) DIFFERENCE-IN-DIFFERENCES changes in industry productivity
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Comprehensive Control Measures and Effect Evaluation of Groundwater Over-exploitation Areas in High-tech Zone,Jining in 2020
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作者 Shengqing LI Fei XIE 《Meteorological and Environmental Research》 CAS 2022年第3期82-85,共4页
Groundwater over-exploitation is a major problem in groundwater development, utilization and protection. At present, the area of shallow groundwater over-exploitation in the High-tech Zone is 76 km^(2). In this study,... Groundwater over-exploitation is a major problem in groundwater development, utilization and protection. At present, the area of shallow groundwater over-exploitation in the High-tech Zone is 76 km^(2). In this study, the system and mechanism construction, engineering measure construction, and control effect of national comprehensive control project of groundwater over-exploitation areas in the High-tech Zone in 2020 were evaluated, and the comprehensive control of groundwater over-exploitation in the High-tech Zone in the year was summarized to provide effective basis for the continuous implementation of comprehensive control of groundwater over-exploitation. At the same time, the water-saving and exploitation reduction effect and generalizability of different measures were studied to provide useful reference for other over-exploitation areas. 展开更多
关键词 GROUNDWATER Over-exploitation area Exploitation reduction effect high-tech zone Jining
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Economic Development Strategies and Optimization of High-tech Development Zones from the Perspective of"Four-transform and Three-famous":Taking Nanchang High-tech Development Zone as an Example
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作者 Zhikang DENG Meixuan REN 《Asian Agricultural Research》 2020年第7期8-11,共4页
In recent years,high-tech development zones(hi-tech zones)have always occupied a very important position in the strategy of promoting China's innovative development.The combination of the"four-transform and t... In recent years,high-tech development zones(hi-tech zones)have always occupied a very important position in the strategy of promoting China's innovative development.The combination of the"four-transform and three-famous"coordinated economic development strategy pioneered by Zhejiang Province in 2015 and the coordinated economic development of high-tech zones is particularly important for modern China at a critical time for innovative economic development.In this article,based on the research on the coordination mechanism of economic activities and development of Nanchang High-tech Zone,the development course of high-tech zones in China is elaborated,the early economic models in high-tech zones of Nanchang and China are analyzed,the existing problems in the structure of economic development of high-tech zones are analyzed in depth,the main driving factors for promoting the economic development of high-tech zones are studied from the aspects of capital,space,industry,economic model,etc.,and corresponding development strategies for high-tech development zones in China are proposed. 展开更多
关键词 Four-transform and three-famous National high-tech development zone Economic development Strategy and optimization Innovative technology
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Evolution of Industrial Competitiveness Based on Evaluation of Urban Competitiveness of Dongguan City:A Case Study of Songshan Lake High-tech Zone
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作者 TANG Shiyu LU Bin HE Dongran 《Journal of Landscape Research》 2020年第3期57-64,共8页
Based on the theoretical system of urban competitiveness,the evaluation model of urban competitiveness from the perspective of competition and cooperation was established.According to the significance index and explan... Based on the theoretical system of urban competitiveness,the evaluation model of urban competitiveness from the perspective of competition and cooperation was established.According to the significance index and explanatory index,the urban competitiveness was divided into urban comprehensive competitiveness(UC),urban internal node competitiveness(NC)and external competitiveness of urban network(EC).The scores and rankings of UC,NC and EC in 2006,2010 and 2015 were obtained by conducting the comprehensive evaluation of the urban competitiveness of Dongguan City with integrated usage of the principal component analysis and Technique for Order Preference by Similarity to an Ideal Solution and the data of other 20 cities in Guangdong province,Hong Kong and Macao.The research showed that the competitiveness of Dongguan City has been greatly improved during the decade of 2006–2015,and the regional cities in Guangdong Province had significant differences,which are reflected in the two dimensions of urban internal node competitiveness(NC)and external competitiveness of urban network(EC).Based on this,this study further analyzed Dongguan’s urban competitiveness from two dimensions of NC and EC,and took Dongguan Songshan Lake High-tech Zone as an example to study how to promote Dongguan’s urban competitiveness from the industrial level. 展开更多
关键词 Dongguan Songshan Lake high-tech zone External competitiveness of urban network Improvement of comprehensive competitiveness
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High-tech Industrial Development Zones in Nanjing,Suzhou,Changzhou and Wuxi
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《China's Foreign Trade》 1996年第12期16-16,共1页
Nanjing High-tech Industrial Devel-opment Zone It is a state-level high-tech in-dustrial development zone approved by theState Council, with an area of 16.5 sq km,comprising seven sq km of industrial area,five sq km o... Nanjing High-tech Industrial Devel-opment Zone It is a state-level high-tech in-dustrial development zone approved by theState Council, with an area of 16.5 sq km,comprising seven sq km of industrial area,five sq km of Taiwan invested area, three sqkm of university teaching and scientificresearch area and 1.5 sq km of compositeservice area. The development zone is 13.5 kmfrom the city center, with convenient trafficconditions, three state highways and a pro- 展开更多
关键词 area HIGH high-tech Industrial Development zones in Nanjing Suzhou Changzhou and Wuxi
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Characteristics and Development Modes of Standardization forChina's National High-Tech Zones:A Review
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作者 郑巧英 田川 徐成华 《China Standardization》 2012年第2期52-57,共6页
Indigenous innovation focused on the development of technical standards has become the core of China's innovation policy,since China released the "Outline of the National Program for Longand Medium-Term Scien... Indigenous innovation focused on the development of technical standards has become the core of China's innovation policy,since China released the "Outline of the National Program for Longand Medium-Term Scientific and Technological Development (2006-2020)" in 2006.Meanwhile,standardization issues are greatly emphasized by high-tech zones which serve as the major carriers of national economic growth as well as innovation clusters in the context of fast-growing international standardization.By means of the effective guide of the government,the standardization of high-tech zones in China now presents a wide range of operating modes.Specifically,they can be divided predominantly into the government promotion mode,the alliance collaboration mode,the research-standard-industry linkage mode,and the talent training mode,in terms of the main body of work and influence factors. 展开更多
关键词 National high-tech zone STANDARDIZATION standard development modes
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Early Triassic Volcanic Rocks in the Western Yarlung Zangbo Suture Zone:Implications for the Opening of the Neo-Tethys Ocean 被引量:1
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作者 HE Juan LI Yalin +4 位作者 HOU Yunling ZHOU Aorigele WEI Yushuai CHEN Xi DAI Jingen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期324-336,共13页
In this study,zircon U-Pb dating of volcanic rocks from the Zhongba ophiolite of the Yarlung Zangbo Suture Zone(YZSZ)in southern Xizang(Tibet)yielded an age of 247±3 Ma.According to whole rock geochemical and Sr-... In this study,zircon U-Pb dating of volcanic rocks from the Zhongba ophiolite of the Yarlung Zangbo Suture Zone(YZSZ)in southern Xizang(Tibet)yielded an age of 247±3 Ma.According to whole rock geochemical and Sr-NdPb isotopic data,the Early Triassic samples could be divided into two groups:Group 1 with P-MORB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70253–0.70602,ε_(Nd)(t)values of 4.2–5.3,(^(206)Pb/^(204)Pb)_(t)ratios of 16.353–18.222,(^(207)Pb/^(204)Pb)_(t)ratios of 15.454–15.564,and(^(208)Pb/^(204)Pb)_(t)ratios of 35.665–38.136;Group 2 with OIB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70249–0.70513,ε_(Nd)(t)values of 4.4–4.9,(^(206)Pb/^(204)Pb)_(t)ratios of 17.140–18.328,(^(207)Pb/^(204)Pb)_(t)ratios of 15.491–15.575,and(^(208)Pb/^(204)Pb)_(t)ratios of 36.051–38.247.Group 2 rocks formed by partial melting of the mantle source enriched by a former plume,and assimilated continental crustal material during melt ascension.The formation of Group 1 rocks corresponds to the mixing of OIB melts,with the same components as Group 2 and N-MORBs.The Zhongba Early Triassic rocks belong to the continental margin type ophiolite and formed in the continental–oceanic transition zone during the initial opening of the Neo-Tethys in southern Xizang(Tibet). 展开更多
关键词 RIFT Early Triassic magmatism Yarlung Zangbo Suture zone NEO-TETHYS Southern Xizang TIBET
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Improving creep strength of the fine-grained heat-affected zone of novel 9Cr martensitic heat-resistant steel via modified thermo-mechanical treatment 被引量:1
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作者 Jingwen Zhang Liming Yu +6 位作者 Yongchang Liu Ran Ding Chenxi Liu Zongqing Ma Huijun Li Qiuzhi Gao Hui Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1037-1047,共11页
The infamous type Ⅳ failure within the fine-grained heat-affected zone (FGHAZ) in G115 steel weldments seriously threatens the safe operation of ultra-supercritical (USC) power plants.In this work,the traditional the... The infamous type Ⅳ failure within the fine-grained heat-affected zone (FGHAZ) in G115 steel weldments seriously threatens the safe operation of ultra-supercritical (USC) power plants.In this work,the traditional thermo-mechanical treatment was modified via the replacement of hot-rolling with cold rolling,i.e.,normalizing,cold rolling,and tempering (NCT),which was developed to improve the creep strength of the FGHAZ in G115 steel weldments.The NCT treatment effectively promoted the dissolution of preformed M_(23)C_(6)particles and relieved the boundary segregation of C and Cr during welding thermal cycling,which accelerated the dispersed reprecipitation of M_(23)C_(6) particles within the fresh reaustenitized grains during post-weld heat treatment.In addition,the precipitation of Cu-rich phases and MX particles was promoted evidently due to the deformation-induced dislocations.As a result,the interacting actions between precipitates,dislocations,and boundaries during creep were reinforced considerably.Following this strategy,the creep rupture life of the FGHAZ in G115 steel weldments can be prolonged by 18.6%,which can further push the application of G115 steel in USC power plants. 展开更多
关键词 G115 steel fine-grained heat-affected zone creep strength element segregation nano-sized precipitates
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Vibration Control of A Flexible Marine Riser System Subject to Input Dead Zone and Extraneous Disturbances 被引量:1
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作者 ZHOU Li WANG Guo-rong WAN Min 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期271-284,共14页
An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control... An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller. 展开更多
关键词 adaptive backstepping control disturbance observer flexible marine riser input dead zone vibration control
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Chengdu High-Tech Zone
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《China Today》 2001年第4期28-29,共2页
关键词 Chengdu high-tech zone
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One-year results for myopia control of orthokeratology with different back optic zone diameters: a randomized trial using a novel multispectral-based topographer 被引量:1
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作者 Wen-Ting Tang Xiang-Ning Luo +4 位作者 Wen-Jing Zhao Jia Liao Xin-Yue Xu Hui-Dan Zhang Li Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期324-330,共7页
AIM:To present the 1-year results of a prospective cohort study investigating the efficacy,potential mechanism,and safety of orthokeratology(ortho-k)with different back optic zone diameters(BOZD)for myopia control in ... AIM:To present the 1-year results of a prospective cohort study investigating the efficacy,potential mechanism,and safety of orthokeratology(ortho-k)with different back optic zone diameters(BOZD)for myopia control in children.METHODS:This randomized clinical study was performed between Dec.2020 and Dec.2021.Participants were randomly assigned to three groups wearing ortho-k:5 mm BOZD(5-MM group),5.5 mm BOZD(5.5-MM group),and 6 mm BOZD(6-MM group).The 1-year data were recorded,including axial length,relative peripheral refraction(RPR,measured by multispectral refractive topography,MRT),and visual quality.The contrast sensitivity(CS)was evaluated by CSV-1000 instrument with spatial frequencies of 3,6,12,and 18 cycles/degree(c/d);the corneal higher-order aberrations(HOAs)were measured by iTrace aberration analyzer.The one-way ANOVA was performed to assess the differences between the three groups.The correlation between the change in AL and RPR was calculated by Pearson’s correlation coefficient.RESULTS:The 1-year results of 20,21,and 21 subjects in the 5-MM,5.5-MM,and 6-MM groups,respectively,were presented.There were no statistical differences in baseline age,sex,or ocular parameters between the three groups(all P>0.05).At the 1-year visit,the 5-MM group had lower axial elongation than the 6-MM group(0.07±0.09 vs 0.18±0.11 mm,P=0.001).The 5-MM group had more myopic total RPR(TRPR,P=0.014),with RPR in the 15°–30°(RPR 15–30,P=0.015),30°–45°(RPR 30–45,P=0.011),temporal(RPR-T,P=0.008),and nasal area(RPR-N,P<0.001)than the 6-MM group.RPR 15–30 in the 5.5-MM group was more myopic than that in the 6-MM group(P=0.002),and RPR-N in the 5-MM group was more myopic than that in the 5.5-MM group(P<0.001).There were positive correlations between the axial elongation and the change in TRPR(r=0.756,P<0.001),RPR 15–30(r=0.364,P=0.004),RPR 30–45(r=0.306,P=0.016),and RPR-N(r=0.253,P=0.047).The CS decreased at 3 c/d(P<0.001),and the corneal HOAs increased in the 5-MM group(P=0.030).CONCLUSION:Ortho-k with 5 mm BOZD can control myopia progression more effectively.The mechanism may be associated with greater myopic shifts in RPR. 展开更多
关键词 relative peripheral refraction ORTHOKERATOLOGY MYOPIA back optic zone diameter axial length multispectral refractive topography
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High-tech Industrial Zones Take Lead in Industrial Innovation
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《China Textile》 2011年第1期8-8,共1页
China’s 56 leading high-tech industrial zones have led the country’s industrial innovation, playing an important role in the nation’s social and economic development, a government statement said on Jan 1.
关键词 high-tech Industrial zones Take Lead in Industrial Innovation THAN GDP
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The Influence of the Closure of the East Paleo-Tethys Ocean on Southern South China:Evidences from Kinematics and^(40)Ar/^(39)Ar Geochronology of the Rongxian Ductile Shear Zone in Southeastern Guangxi 被引量:1
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作者 HUANG Wenqiang LI Saisai +5 位作者 XIN Liangwei FENG Zuohai ZHANG Hongrui GENG Jieli LIU Kun SHI Chunyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1125-1140,共16页
The Triassic was a crucial period in the tectonic evolution of the South China Block.Research on tectonic deformation during this period provides information on intracontinental orogenic mechanisms in South China.In t... The Triassic was a crucial period in the tectonic evolution of the South China Block.Research on tectonic deformation during this period provides information on intracontinental orogenic mechanisms in South China.In this study,alongside thermochronological analyses,we examine the macroscopic and microscopic structural features of the Rongxian ductile shear zone,located south of the Darongshan granite in the southeastern part of Guangxi Province,on the southern margin of South China.Sinistral shear is indicated by the characteristics of rotatedσ-type feldspar porphyroclasts,stretching lineations defined by elongated quartz grains and the orientations of quartz c-axes.LA-ICP-MS U-Pb dating of zircons from two samples of granitic mylonite and one of granite yielded ages of ca.256 Ma.Furthermore,two samples of granitic mylonite yield muscovite^(40)Ar/^(39)Ar plateau ages of 249-246 Ma.These results indicate that the Rongxian ductile shear zone resulted from Early Triassic deformation of the late Permian Darongshan granite.This deformation was likely related to the closure of the eastern Paleo-Tethys Ocean and the subsequent collision of the South China and Indochina blocks,during the early stage of the Indosinian orogeny. 展开更多
关键词 ductile shear zone ^(40)Ar/^(39)Ar geochronology TRIASSIC South China Block East Paleo-Tethys Ocean
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Dynamic Identification and Evolution of Urban-suburban-rural Transition Zones Based on the Blender of Natural and Humanistic Factors: A Case Study of Chengdu, China
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作者 DENG Wei JIANG Zhenyuan +3 位作者 ZHANG Shaoyao REN Ping ZHANG Hao WANG Zhanyun 《Chinese Geographical Science》 SCIE CSCD 2024年第5期791-809,共19页
Urban-suburban-rural(U-S-R)zones exhibit distinctive transitional characteristics in interaction between human and nature.U-S-R transition zones(U-S-RTZ)are also highlighting the function diversity and landscape heter... Urban-suburban-rural(U-S-R)zones exhibit distinctive transitional characteristics in interaction between human and nature.U-S-R transition zones(U-S-RTZ)are also highlighting the function diversity and landscape heterogeneity across territorial spaces.As a super megacity in western China,Chengdu’s rapid urbanization has driven the evolution of U-S-R spaces,resulting in a sequential structure.To promote the high-quality spatial development of urban-rural region in a structured and efficient manner,it is essential to con-duct a scientific examination of the multidimensional interconnection within the U-S-RTZ framework.By proposing a novel identifica-tion method of U-S-RTZ and taking Chengdu,China as a case study,grounded in a blender of natural and humanistic factors,this study quantitatively delineated and explored the spatial evolutions of U-S-RTZ and stated the optimization orientation and sustainable devel-opment strategies of the production-living-ecological spaces along the U-S-R gradients.The results show that:1)it is suitable for the quantitative analysis of U-S-RTZ by established three-dimensional identification system in this study.2)In 1990-2020,the urban-sub-urban transition zones(U-STZ)in Chengdu have continuously undergone a substantial increase,and the scale of the suburban-rural transition zones(S-RTZ)has continued to expand slightly,while the space of rural-ecological transition zones(R-ETZ)has noticeably compressed.3)The landuse dynamics within U-S-RTZ has gradually increased in 1990-2020.The main direction of landuse transition was from farmland to construction land or woodlands,with the expansion of construction land being the most significant.4)R-ETZ primarily focus on ecological functions,and there is a trade-off relationship between the production-ecological function within the S-RTZ,and in the U-STZ,production-living composite functions are prioritized.This study emphasizes the importance of elastic planning and precise governance within the U-S-RTZ in a rapid urbanization region,particularly highlighting the role of suburbs as landscape corridors and service hubs in urban-rural integration.It elucidates to the practical implications for achieving high-quality development of integrated U-S-R territorial spaces. 展开更多
关键词 transition zone urban-suburban-rural zones spatial identification evolution mechanism Chengdu China
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Advances in seismological methods for characterizing fault zone structure
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作者 Yan Cai Jianping Wu +1 位作者 Yaning Liu Shijie Gao 《Earthquake Science》 2024年第2期122-138,共17页
Large earthquakes frequently occur along complex fault systems.Understanding seismic rupture and long-term fault evolution requires constraining the geometric and material properties of fault zone structures.We provid... Large earthquakes frequently occur along complex fault systems.Understanding seismic rupture and long-term fault evolution requires constraining the geometric and material properties of fault zone structures.We provide a comprehensive overview of recent advancements in seismological methods used to study fault zone structures,including seismic tomography,fault zone seismic wave analysis,and seismicity analysis.Observational conditions limit our current ability to fully characterize fault zones,for example,insufficient imaging resolution to discern small-scale anomalies,incomplete capture of crucial fault zone seismic waves,and limited precision in event location accuracy.Dense seismic arrays can overcome these limitations and enable more detailed investigations of fault zone structures.Moreover,we present new insights into the structure of the Anninghe-Xiaojiang fault zone in the southeastern margin of the Qinghai-Xizang Plateau based on data collected from a dense seismic array.We found that utilizing a dense seismic array can identify small-scale features within fault zones,aiding in the interpretation of fault zone geometry and material properties. 展开更多
关键词 fault zone structure TOMOGRAPHY fault zone wave seismic activity Anninghe-Xiaojiang fault zone
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