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Relational characteristics and dynamics between high-tech firms in the Pearl River Delta and the empowerment for technological innovation by Hong Kong

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Journal of Geographical Sciences 2025年第2期35卷 382-408页

作者： XU Jili Anthony G.O.YEH George C.S.LIN LIU Xingjian YANG Fan Fiona LUO Zixin Guangzhou Institute of geography Guangdong Academy of Sciences Department of Urban planning and Design The University of Hong Kong Department of geography The University of Hong Kong school of geography and planning Sun Yat-Sen University

The perfection of the cross-border regional innovation system of the Pearl River Delta(PRD) and Hong Kong remarkably underpins the construction of the Guangdong-Hong Kong-Macao Greater Bay Area(GBA) towards an international technological innovation *** paper focuses on the relational characteristics of the usage of technological innovation functions and elements, including labor force, technology, and producer services from Hong Kong by high-technology firms in the PRD, and probes into the influencing factors by integrating the objective perspective on the impact of firm-level socioeconomic attributes and subjective perspective on the open interpretations on the reasons by using or not using technological innovation functions and elements from Hong Kong by various stakeholders in high-technology domains in the PRD. Key research findings are fourfold. First, Hong Kong's technological innovation functions primarily ride on its institutional advantages under the “One Country, Two Systems” framework to empower high-technology firms in the PRD by expanding their international market, international business operation, and financing, but cross-border investment and entrepreneurship has retrieved to a relatively marginalized position. The degree of supply-demand relations of producer services is the highest, followed by labor force and ***, Hong Kong-invested, large-sized, and long-standing high-technology firms in the PRD are more inclined to use technological innovation elements from Hong Kong, while domestic,small-and-medium-sized, and start-up high-technology firms in the PRD are in turn, gradually unhooked from the supply of technological innovation elements from Hong Kong. Third, Hong Kong enjoys both advantages and disadvantages in supplying labor forces, technologies, and producer services to high-technology firms in the PRD, with advantages in competitiveness,international linkages and visions, and disadvantages in high cost, lack of more profoun

关键词： Guangdong-Hong Kong-Macao Greater Bay Area high-technology firms high-technology industries Hong Kong Pearl River Delta regional innovation system

Digital Economy's Impact on Carbon Emission Performance:Evidence from the Yangtze River Delta, China

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Chinese Geographical Science 2025年第2期 217-233页

作者： ZHANG Xinlin QIU Fangdao LIU Jibin school of geography Geomatics and Planning Jiangsu Normal University school of Geographical Science Jiangsu Second Normal University school of Architecture and Urban planning Jilin Jianzhu University

Climate change caused by carbon emissions is a hot topic of concern. Enhancing carbon emission performance(CEP)emerges as a pivotal strategy to curtail carbon emissions, with the digital economy recognized as a crucial instrument for bolstering CEP. Grounded in theoretical analysis, this article takes the Yangtze River Delta region(YRD) as the research object and conducts empirical analysis for the period from 2010 to 2021. The Super Epsilon-Based Measure(EBM) model was employed to assess CEP, while the entropy method was used to quantify the level of the digital economy. Baseline regression models and mediation effect models were constructed to test the research hypotheses. Additionally, the Spatial Durbin Model(SDM) was utilized to analyze the spatial spillover effects of the digital economy. Some conclusions were drawn as follows. Firstly, both the digital economy and CEP exhibit growing trends and demonstrate significant spatial distribution characteristics. Cities with high CEP are increasingly concentrated along the Yangtze River and coastal areas. Meanwhile, the digital economy generally demonstrates a spatial distribution pattern of being higher in the southeast and lower in the northwest. Secondly, the digital economy exerts a notable and consistent positive influence on CEP, but this impact is not primarily achieved through promoting green technology innovation. Instead, the digital economy exhibits a stronger intermediary effect on CEP by facilitating industrial structure upgrading and rationalization. Thirdly, the digital economy significantly enhancing local CEP but having an insignificant impact on neighboring cities' CEP. To address these findings, cities ought to invest in digital infrastructure, incentivize digital innovation through policy and financial backing, and harness advanced technologies like 5G and blockchain to promote low-carbon, intelligent production and lifestyles, while enhancing industrial structure and regional cooperation to foste

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Different mechanisms of Eurasian snow cover on precipitation during the early and late pre-rainy season in South China

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Science China Earth Sciences 2025年第3期68卷 882-897页

作者： Zhixiang XIAO Anmin DUAN Yuhang CHEN Chen WEI Xiaoli LUO school of geography and planning Nanning Normal University State Key Laboratory of Marine Environmental Science College of Ocean and Earth Sciences Xiamen University Guangxi Climate Center

The interannual variability in precipitation during the pre-rainy season(PRS) in South China is significantly correlated with Eurasian snow cover. This study elucidates the distinct mechanisms by which Eurasian snow cover anomalies in March influence precipitation during the early(pre-monsoon) and late(post-monsoon) PRS. In the early PRS, anomalous snow cover in the western region of Eastern Europe(WEE) triggers a southeastward-propagating wave train that impacts Central *** teleconnection pattern induces anomalous cyclonic circulation in Central Asia, which reinforces the midlatitude zonal wind,contributing to the zonal wind wave train pattern towards East Asia. As a result, the East Asian subtropical westerly jet and the western North Pacific subtropical high are enhanced, and the related upper-level divergence, ascending motion, and moisture convergence in South China are intensified, collectively promoting precipitation there. In contrast, during the late PRS, increased snow cover across the eastern sector of Eastern Europe(EEE) and the region east of Lake Baikal(ELB) inhibit South China's precipitation. The wave pattern associated with the EEE(ELB) snow anomaly propagates southeastwards(southwards) to lower latitudes, intensifying the western North Pacific subtropical high. Furthermore, the perturbation stemming from the ELB region induces negative geopotential height anomalies aloft and amplifies the baroclinic anticyclone over the western Pacific. This resulted in prevailing subsidence over South China, which in turn suppresses precipitation during the late PRS. Numerical experiments corroborate the observed circulation adjustments and precipitation responses to snow cover anomalies in the two periods, lending credence to the proposed mechanisms.

关键词： Eurasian snow cover Pre-rainy season South China Wave train

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Land use/cover change and ecological network in Gansu Province,China during 2000-2020 and their simulations in 2050

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Journal of Arid Land 2025年第1期17卷 43-57页

作者： MA Xinshu XIN Cunlin CHEN Ning XIN Shunjie CHEN Hongxiang ZHANG Bo KANG Ligang WANG Yu JIAO Jirong College of geography and Environmental Science Northwest Normal UniversityLanzhou 730070China College of Earth and Environment Science Lanzhou UniversityLanzhou 730030China school of Architecture and Urban planning Lanzhou Jiaotong UniversityLanzhou 730070China

Land use/cover change(LUCC)constitutes the spatial and temporal patterns of ecological security,and the construction of ecological networks is an effective way to ensure ecological *** the spatial and temporal change characteristics of ecological network and analyzing the integrated relationship between LUCC and ecological security are crucial for ensuring regional ecological *** is one of the provinces with fragile ecological environment in China,and rapid changes in land use patterns in recent decades have threatened ecological ***,taking Gansu Province as the study area,this study simulated its land use pattern in 2050 using patch-generating land use simulation(PLUS)model based on the LUCC trend from 2000 to 2020 and integrated the LUCC into morphological spatial pattern analysis(MSPA)to identify ecological sources and extract the ecological corridors to construct ecological network using circuit *** results revealed that,according to the prediction results in 2050,the areas of cultivated land,forest land,grassland,water body,construction land,and unused land would be 63,447.52,39,510.80,148,115.18,4605.21,8368.89,and 161,752.40 km^(2),*** number of ecological sources in Gansu Province would increase to 80,with a total area of 99,927.18 km^(2).The number of ecological corridors would increase to 191,with an estimated total length of 6120.66 *** ecological sources and ecological corridors showed a sparse distribution in the northwest and dense distribution in the southeast of the province at the spatial *** number of ecological pinch points would reach 312 and the total area would expect to increase to 842.84 km^(2),with the most pronounced increase in the Longdong *** with 2020,the number and area of ecological barriers in 2050 would decrease significantly by 63 and 370.71 km^(2),*** general,based on the prediction results,the connectivity of ecological network of Gansu

关键词： patch-generating land use simulation(PLUS)model morphological spatial pattern analysis(MSPA) circuit theory ecological source ecological resistance surface ecological corridor ecological pinch point

Extraction of gravel characteristics and spatial inversion for ecological restoration monitoring in the Northern Tibetan Plateau

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Journal of Mountain Science 2025年第2期22卷 556-574页

作者： KONG Bo YU Huan QIU Xia HU Wenkai HE Bing GUAN Xudong Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China College of geography and planning Chengdu University of TechnologyChengdu 610059China Tibet Geological Environment Monitoring Center Lhasa 850000China school of Computer Science Chengdu University of Information TechnologyChengdu 610225China Sichuan Real Estate Registration Center(Sichuan Provincial Land and Cadastral Affairs Center) Chengdu 610072China

Previous studies have often focused on monitoring grassland growth as the primary target of remote sensing investigations on grassland ecological restoration in the northern Tibetan Plateau,overlooking the crucial role played by gravel in the ecological restoration of these *** study utilizes supervised classification and segmentation techniques based on machine learning to extract gravel morphology profiles from field-sampled plot images and calculate their characteristic *** a multivariate linear approach combined with Principal Component Analysis(PCA),a model for inferring gravel characteristic parameters is *** features,particle size characteristics,and spatial distribution patterns of gravel are *** reveal that gravel predominantly exhibit sub-rounded shapes,with 80%classified as fine *** coefficients of determination(R2)between gravel particle size and coverage,perimeter,and area are 0.444,0.724,and 0.557,respectively,indicating linear *** cumulative contribution rate of the top five remote sensing factors is 95.44%,with the first geological factor contributing 77.64%,collectively reflecting the primary information of the 20 factors *** shows that areas with larger gravel particle sizes correspond to increased perimeter and *** in the Nagqu Prefecture of northern Tibet have a particle size range of 4-8 mm,primarily comprising fine gravel which accounts for 94.61%.These findings provide a scientific basis for extracting gravel characteristic parameters and understanding their spatial distribution variations in the northern Tibetan Plateau.

关键词： Gravel characteristics parameters Northern Tibetan Plateau Gravel outline extraction Remote sensing inversion Grassland degradation

Light Use Efficiency Model Based on Chlorophyll Content Better Captures Seasonal Gross Primary Production Dynamics of Deciduous Broadleaf Forests

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Chinese Geographical Science 2025年第1期35卷 55-72页

作者： YANG Rongjuan LIU Ronggao LIU Yang CHEN Jingming XU Mingzhu HE Jiaying State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China university of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Humid Subtropical Ecogeographical Processes of the Ministry of Education School of Geographical SciencesFujian Normal UniversityFuzhou 350007China Department of geography and planning University of TorontoTorontoON M5S 3G3Canada

Gross primary production(GPP)is a crucial indicator representing the absorption of atmospheric CO_(2) by *** present,the estimation of GPP by remote sensing is mainly based on leaf-related vegetation indexes and leaf-related biophysical para-meter leaf area index(LAI),which are not completely synchronized in seasonality with *** this study,we proposed chlorophyll content-based light use efficiency model(CC-LUE)to improve GPP estimates,as chlorophyll is the direct site of photosynthesis,and only the light absorbed by chlorophyll is used in the photosynthetic *** CC-LUE model is constructed by establishing a linear correlation between satellite-derived canopy chlorophyll content(Chlcanopy)and *** method was calibrated and validated utiliz-ing 7-d averaged in-situ GPP data from 14 eddy covariance flux towers covering deciduous broadleaf forest ecosystems across five dif-ferent climate *** showed a relatively robust seasonal consistency between Chlcanopy with GPP in deciduous broadleaf forests under different climatic *** CC-LUE model explained 88% of the in-situ GPP seasonality for all validation site-year and 56.0% of in-situ GPP variations through the growing season,outperforming the three widely used LUE models(MODIS-GPP algorithm,Vegetation Photosynthesis Model(VPM),and the eddy covariance-light use efficiency model(EC-LUE)).Additionally,the CC-LUE model(RMSE=0.50 g C/(m^(2)·d))significantly improved the underestimation of GPP during the growing season in semi-arid region,re-markably decreasing the root mean square error of averaged growing season GPP simulation and in-situ GPP by 75.4%,73.4%,and 37.5%,compared with MOD17(RMSE=2.03 g C/(m^(2)·d)),VPM(RMSE=1.88 g C/(m^(2)·d)),and EC-LUE(RMSE=0.80 g C/(m^(2)·d))*** chlorophyll-based method proved superior in capturing the seasonal variations of GPP in forest ecosystems,thereby provid-ing the possibility of a more precise depiction of forest seasonal carbon uptake.

关键词： canopy chlorophyll content(Chlcanopy) photosynthesis gross primary production(GPP) light use efficiency(LUE)model seasonal dynamics deciduous broadleaf forest(DBF)

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Rainfall impacts on nonpoint nitrogen and phosphorus dynamics in an agricultural river in subtropical montane reservoir region of southeast China

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Journal of Environmental Sciences 2025年第3期149卷 551-563页

作者： Yuanyi Wang Hai Xu Xingchen Zhao Lijuan Kang Yu Qiu Hans Paerl Guangwei Zhu Huiyun Li Mengyuan Zhu Boqiang Qin Yunlin Zhang Mingliang Liu Key Laboratory of Lake and Watershed Science for Water Security Nanjing Institute of Geography&LimnologyChinese Academy of SciencesNanjing 210008China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China school of geography and Ocean Science Nanjing UniversityNanjing 210023China Institute of Marine Sciences University of North Carolina at Chapel HillNC 28557USA Hangzhou Institute of Ecological and Environmental Sciences Hangzhou 310005China

The increased frequency and intensity of heavy rainfall events due to climate change could potentially influence the movement of nutrients from land-based regions into recipient ***,little information is available on how the rainfall affect nutrient dynamics in subtropicalmontane rivers with complex land *** study conducted high-frequency monitoring to study the effects of rainfall on nutrients dynamics in an agricultural river draining to Lake Qiandaohu,a montane reservoir of southeast *** results showed that riverine total nitrogen(TN)and total phosphorus(TP)concentrations increased continuously with increasing rainfall intensity,while TN:TP *** heavy rainfall and rainstorm drove more than 30%of the annual N and P loading in only 5.20%of the total rainfall period,indicating that increased storm runoff is likely to exacerbate eutrophication in montane ***_(3)^(−)-N is the primary nitrogen form lost,while particulate phosphorus(PP)dominated phosphorus *** source of N is cropland,and themain source of P is residential ***,forestedwatersheds have better drainage quality,while it is still a potential source of nonpoint pollution during rainfall *** and TP concentrations were significantly higher at sites dominated by cropland and residential area,indicating their substantial contributions to deteriorating river water ***,TN and TP concentrations reached high values in May-August when rainfall was most intense,while they were lower in autumn and winter than that in spring and summer under the same rainfall *** results emphasize the influence of rainfall-runoff and land use on dynamics of riverine N and P loads,providing guidance for nutrient load reduction planning for Lake Qiandaohu.

关键词： Non-point source pollution Rainfall events Land use type Mountain area Deepwater reservoir

Spatial non-stationary characteristics between temperate grasslands based on a mixed geographically weighted regression model

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Journal of Geographical Sciences 2022年第6期32卷 1076-1102页

作者： SONG Xiaolong MI Nan MI Wenbao LI Longtang College of Agriculture Ningxia UniversityYinchuan 750021China school of geography and planning Ningxia UniversityYinchuan 750021China

Spatial models are effective in obtaining local details on grassland biomass,and their accuracy has important practical significance for the stable management of grasses and *** this end,the present study utilized measured quadrat data of grass yield across different regions in the main growing season of temperate grasslands in ningxia of China(August 2020),combined with hydrometeorology,elevation,net primary productivity(NPP),and other auxiliary data over the same ***,non-stationary characteristics of the spatial scale,and the effects of influencing factors on grass yield were analyzed using a mixed geographically weighted regression(MGWR)*** results showed that the model was suitable for correlation *** spatial scale of ratio resident-area index(PRI)was the largest,followed by the digital elevation model,NPP,distance from gully,distance from river,average July rainfall,and daily temperature range;whereas the spatial scales of night light,distance from roads,and relative humidity(RH)were the most *** influencing factors maintained positive and negative effects on grass yield,save for the strictly negative effect of *** regression results revealed a multiscale differential spatial response regularity of different influencing factors on grass *** parameters revealed that the results of Ordinary least squares(OLS)(Adjusted R^(2)=0.642)and geographically weighted regression(GWR)(Adjusted R^(2)=0.797)models were worse than those of MGWR(Adjusted R^(2)=0.889)*** on the results of the RMSE and radius index,the simulation effect also was MGWR>GWR>OLS ***,the MGWR model held the strongest prediction performance(R^(2)=0.8306).Spatially,the grass yield was high in the south and west,and low in the north and east of the study *** results of this study provide a new technical support for rapid and accurate estimation of grassland yield to dynamically adjust grazing decision in the semi-ar

关键词： grass yield spatial non-stationary mixed geographically weighted regression model temperate grassland ningxia

Control Structures and Algorithms for Force Feedback Bilateral Teleoperation Systems: A Comprehensive Review

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Computer Modeling in Engineering & Sciences 2025年第2期142卷 973-1019页

作者： Jiawei Tian Yu Zhou Lirong Yin Salman A.AlQahtani Minyi Tang Siyu Lu Ruiyang Wang Wenfeng Zheng Department of Computer Science and Engineering Major in Bio Artificial IntelligenceHanyang UniversityAnsan-si15577Republic of Korea Department of geography and Anthropology Louisiana State UniversityBaton RougeLA 70803USA Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityRiyadh11574Saudi Arabia school of Automation University of Electronic Science and Technology of ChinaChengdu610054China

Force feedback bilateral teleoperation represents a pivotal advancement in control technology,finding widespread application in hazardous material transportation,perilous environments,space and deep-sea exploration,and healthcare *** paper traces the evolutionary trajectory of force feedback bilateral teleoperation from its conceptual inception to its current *** elucidates the fundamental principles underpinning interaction forces and tactile exchanges,with a specific emphasis on the crucial role of tactile *** this review,a quantitative analysis of force feedback bilateral teleoperation development trends from 2011 to 2024 has been conducted,utilizing published journal article data as the primary source of *** review accentuates classical control frameworks and algorithms,while also delving into existing research advancements and prospec-tive breakthrough ***,it explores specific practical scenarios ranging from intricate surgeries to hazardous environment exploration,underscoring the technology’s potential to revolutionize industries by augmenting human manipulation of remote *** underscores the pivotal role of force feedback bilateral teleoperation as a transformative human-machine interface,capable of shaping flexible control strategies and addressing technological *** research endeavors in force feedback bilateral teleoperation are expected to prioritize the creation of more immersive experiences,overcoming technical hurdles,fortifying human-machine collaboration,and broadening application domains,particularly within the realms of medical intervention and hazardous *** the continuous progression of technology,the integration of human intelligence and robotic capabilities is expected to produce more innovations and breakthroughs in the field of automatic control.

关键词： Force feedback bilateral teleoperation robot development history application prospect