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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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Formation mechanism of fault accommodation zones under combined stress in graben basin:Implications from geomechanical modeling
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作者 Qi-Qiang Ren Jin-Liang Gao +3 位作者 Rong-Tao Jiang Jin Wang Meng-Ping Li Jian-Wei Feng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期54-76,共23页
A fault accommodation zone is a type of structure that is defined as regulating displacement and strain between faults structure.Increasing numbers of fault accommodation zones are being identified in graben basins,in... A fault accommodation zone is a type of structure that is defined as regulating displacement and strain between faults structure.Increasing numbers of fault accommodation zones are being identified in graben basins,indicating the potential exploration target and petroleum accumulation areas.This study aims to analyze the formation mechanism and development of fault accommodation zones under combined stress by a numerical simulation method considering geomechanical modeling.Using three-dimensional(3-D)seismic interpretation and fractal dimension method,exampled with the Dongxin fault zone,the fault activity and fault combination pattern were conducted to quantitatively characterize the activity difference in fault accommodation zones.Combined with mechanical experiment test,a geomehcanical model was established for fault accommodation zones in a graben basin.Integrating the paleostress numerical simulations and structural physical simulation experiment,the developmental characteristics and genetic mechanism of fault accommodation zones were summarized.Influenced by multi movements and combined stresses,three significant tectonic evolution stages of the Dongxing Fault Zone(DXFZ)were distinguished:During the E_(s)^(3)sedimentary period,the large difference in the stress,strain,and rupture distribution in various faults were significant,and this stage was the key generation period for the prototype of the DXFZ,including the FAZ between large-scale faults.During the E_(s)^(2)sedimentary period,the EW-trending symmetric with opposite dipping normal faults and the NE-SW trending faults with large scale were furtherly developed.The junction area of two secondary normal faults were prone to be ruptured,performing significant period for inheriting and developing characteristics of fault accommodation zones.During the Es1 sedimentary period,the high-order faults in the DXFZ exhibited the obvious fault depressions and strike-slip activity,and the fault accommodation zones were furtherly inherited and developed.This stage was the molded and formative period of the FAZ,the low-order faults,and the depression in the DXFZ. 展开更多
关键词 Fault accommodation zone Graben basin Fault activity Tectonic physical simulation experiment Finite element numerical simulation Dongxin fault zone
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Twenty-Three Years of Insect Pollinator-Dependent Crop Studies in Agro-Ecological Zones of Cameroon (2011-2020)
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作者 Népidé Ndobadé Carine Egono Ndemé Carole Christèle +1 位作者 Daniel Farda Mazi Sanda 《Agricultural Sciences》 2024年第8期877-908,共32页
Cultivation of pollinator-dependent crops has expanded globally, increasing our reliance on insect pollination. This essential ecosystem service is provided by a wide range of managed and wild pollinators whose abunda... Cultivation of pollinator-dependent crops has expanded globally, increasing our reliance on insect pollination. This essential ecosystem service is provided by a wide range of managed and wild pollinators whose abundance and diversity are thought to be in decline, threatening sustainable food production. In Cameroon, several studies on pollinator-dependent crops carried out in different agro-ecological zones (AEZ) have been published in national and international journals, in order to present the importance and impact of flowering insects on fruit and seed yields of plant species. We proposed to produce a review article highlighting the different flowering insects and their importance for different plants according to AEZ, without however focusing on the quality of the journal (predator or non-predator) and how the different insects were identified (scientific names given in the publications). Thus, from 1997 to 2020, we collected 116 published papers from which only 26 were kept for this review. The results show that Hymenoptera, including the Apidae, followed by Megachilidae, are the most excellent pollinators of plant species in Cameroon, and they are present in different agro-ecological zones. The majority of publications focused on bees, particularly the honeybee Apis mellifera. 展开更多
关键词 Agro-Ecological zones Cameroon Flowering Insects HYMENOPTERA POLLINATORS
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Disparities in Prevalence and Determinants of Hypertension amongst Bamiléké Adults Residing in Two Different Agroecological Zones of Cameroon
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作者 Maxwell Wandji Nguedjo Nanhah Kamga Jules Vidal +7 位作者 Alice Louise Woguia Pauline Vervaine Hagbe David Goda Dany Joël Ngassa Ngoumen Hippolyte Tene Mouafo Boris Gabin Kingue Azantsa Judith Laure Ngondi Julius Enyong Oben 《Open Journal of Epidemiology》 2024年第3期419-443,共25页
Background: Cardiovascular diseases such as hypertension (HTN) are one of the main causes of death in Cameroon. This study aimed at assessing prevalence disparities and determinants of hypertension amongst Bamilé... Background: Cardiovascular diseases such as hypertension (HTN) are one of the main causes of death in Cameroon. This study aimed at assessing prevalence disparities and determinants of hypertension amongst Bamiléké adults residing in two different agroecological zones of Cameroon. Methods: A cross-sectional and descriptive survey was conducted among Bamiléké population living in the Highlands zone (Western region) and in the Monomodal Rainforest zone (Littoral region) of Cameroon from August 2016 to August 2017. Participants (962) were aged at least 20 years old. Data on sociodemographic, hemodynamic, anthropometric, and biochemical parameters and lifestyle of the participants were collected. Results: Results obtained revealed that 34.2% were hypertensive and those residing in the highland zone were more affected than those living in the monomodal rainforest zone (44.5% vs 22.9%). The different subtypes of HTN (Isolated systolic hypertension (14.1%), isolated diastolic hypertension (7.2%) and Systo-diastolic hypertension (23.3%)) were also more prevalent in the Highlands Zone. The most prevalent stage of HTN was pre-HTN (31.5%). However, people living in the monomodal rainforest zone were more affected by pre-HTN compared to Bamiléké living in the highland zone (33.6% vs. 29.6%). Results also showed that high consumption (≥ 3 times/week) of carbohydrate- and fat-rich foods, ageing, obesity, and marital status were associated with high blood pressure in both agroecological zones. Besides, secondary education (OR = 0.68;95% CI: 0.42 - 0.99) in the Highlands Zone and high (≥3 times/week) vegetable consumption (OR = 0.66;95% CI: 0.44 - 0.98) in the Monomodal Rainforest Zone had a protective effect on elevated blood pressure of population. Conclusion: There is a disparity in the prevalence of hypertension and some of its determinants among Bamiléké adults residing in different agroecological zones. This work highlights the need to advocate for local and ethno-cultural health policies to prevent, diagnose and manage hypertension. 展开更多
关键词 HYPERTENSION DISPARITIES Determinants Bamiléké Ethnic Group Agroecological Zone
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Numerical investigation of geostress influence on the grouting reinforcement effectiveness of tunnel surrounding rock mass in fault fracture zones
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作者 Xiangyu Xu Zhijun Wu +3 位作者 Lei Weng Zhaofei Chu Quansheng Liu Yuan Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期81-101,共21页
Grouting is a widely used approach to reinforce broken surrounding rock mass during the construction of underground tunnels in fault fracture zones,and its reinforcement effectiveness is highly affected by geostress.I... Grouting is a widely used approach to reinforce broken surrounding rock mass during the construction of underground tunnels in fault fracture zones,and its reinforcement effectiveness is highly affected by geostress.In this study,a numerical manifold method(NMM)based simulator has been developed to examine the impact of geostress conditions on grouting reinforcement during tunnel excavation.To develop this simulator,a detection technique for identifying slurry migration channels and an improved fluid-solid coupling(FeS)framework,which considers the influence of fracture properties and geostress states,is developed and incorporated into a zero-thickness cohesive element(ZE)based NMM(Co-NMM)for simulating tunnel excavation.Additionally,to simulate coagulation of injected slurry,a bonding repair algorithm is further proposed based on the ZE model.To verify the accuracy of the proposed simulator,a series of simulations about slurry migration in single fractures and fracture networks are numerically reproduced,and the results align well with analytical and laboratory test results.Furthermore,these numerical results show that neglecting the influence of geostress condition can lead to a serious over-estimation of slurry migration range and reinforcement effectiveness.After validations,a series of simulations about tunnel grouting reinforcement and tunnel excavation in fault fracture zones with varying fracture densities under different geostress conditions are conducted.Based on these simula-tions,the influence of geostress conditions and the optimization of grouting schemes are discussed. 展开更多
关键词 Numerical manifold method(NMM) Grouting reinforcement Geostress condition Fault fracture zone Tunnel excavation
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Evaluation of excavation damaged zones(EDZs)in Horonobe Underground Research Laboratory(URL)
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作者 Koji Hata Sumio Niunoya +1 位作者 Kazuhei Aoyagi Nobukatsu Miyara 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期365-378,共14页
Excavation of underground caverns,such as mountain tunnels and energy-storage caverns,may cause the damages to the surrounding rock as a result of the stress redistribution.In this influenced zone,new cracks and disco... Excavation of underground caverns,such as mountain tunnels and energy-storage caverns,may cause the damages to the surrounding rock as a result of the stress redistribution.In this influenced zone,new cracks and discontinuities are created or propagate in the rock mass.Therefore,it is effective to measure and evaluate the acoustic emission(AE)events generated by the rocks,which is a small elastic vibration,and permeability change.The authors have developed a long-term measurement device that incorporates an optical AE(O-AE)sensor,an optical pore pressure sensor,and an optical temperature sensor in a single multi-optical measurement probe(MOP).Japan Atomic Energy Agency has been conducting R&D activities to enhance the reliability of high-level radioactive waste(HLW)deep geological disposal technology.In a high-level radioactive disposal project,one of the challenges is the development of methods for long-term monitoring of rock mass behavior.Therefore,in January 2014,the long-term measurements of the hydro-mechanical behavior of the rock mass were launched using the developed MOP in the vicinity of 350 m below the surface at the Horonobe Underground Research Center.The measurement results show that AEs occur frequently up to 1.5 m from the wall during excavation.In addition,hydraulic conductivity increased by 2e4 orders of magnitude.Elastoplastic analysis revealed that the hydraulic behavior of the rock mass affected the pore pressure fluctuations and caused micro-fractures.Based on this,a conceptual model is developed to represent the excavation damaged zone(EDZ),which contributes to the safe geological disposal of radioactive waste. 展开更多
关键词 Excavation damaged zone(EDZ) Optical sensor Long-term monitoring Acoustic emission(AE) Shaft sinking
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Characteristics of transfer zones under the influence of preexisting faults and regional stress transformation:Wenchang A subsag,Zhujiang River Mouth Basin,northern South China Sea
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作者 Wei LI Mingyue CAO +7 位作者 Meifang MENG Caiwei FAN Hui LI Jia LI Wanqiu WU Ruiqing QIN Xingan LI Yiming LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期744-759,共16页
A transfer zone in rift basins preserves important information on regional tectonic evolution and plays significant roles in hydrocarbon accumulation.Based on the systematic analysis of 3D seismic data and hydrocarbon... A transfer zone in rift basins preserves important information on regional tectonic evolution and plays significant roles in hydrocarbon accumulation.Based on the systematic analysis of 3D seismic data and hydrocarbon accumulation conditions,the geometry,kinematics,and reservoir control of a large synthetic overlapping transfer zone in the south of the Wenchang A subsag in the Zhujiang(Pearl)River Mouth basin were investigated.Results indicate that the development and evolution of the transfer zone was controlled by the interaction between pre-existing faults and regional stress transformation.The intense rifting of the main faults of the transfer zone controlled the development of source rocks and faultcontrolled slope break paleogeomorphology.The strike-slip overprint since the Oligocene is conducive to the formation of a large-scale fault-anticline trap,and the secondary faults in the transfer zone contribute to the hydrocarbon transportation.The conjugate intersection area of the NE-and NW-trending faults offers more opportunity for hydrocarbon migration and accumulation. 展开更多
关键词 transfer zone pre-existing fault regional stress transformation CENOZOIC Wenchang A Subsag Zhujiang(Pearl)River Mouth Basin
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Comparative Study of the Types of Photovoltaic Panels Used in Solar Pumping Systems in Dry Tropical Zones: Case of Adamawa Region in Cameroon
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作者 Boussaibo Andre Waoudowa Kande Veronique +1 位作者 Ndjiya Ngasop Stephane Gautier Kitmo 《Open Journal of Energy Efficiency》 2024年第3期79-87,共9页
In the dry tropical zone where access to water is increasingly difficult for populations, solar pumping units are increasingly installed to provide water to population. In the local market, there are essentially two t... In the dry tropical zone where access to water is increasingly difficult for populations, solar pumping units are increasingly installed to provide water to population. In the local market, there are essentially two types of solar panels, namely monocrystalline and polycrystalline. However, the part of the local market is more dominated by the polycrystalline panel. In this work, comparative studies are carried out in order to characterize the two types of solar panels with regard to local constraints. Tests were carried out over the course of the sun to establish the performance of each type. The panels used have the same electrical characteristics and are connected to loads with same characteristics. Under the set operating conditions, the monocrystalline panel presents more performance than the polycrystalline panel. Although the local market is dominated by the polycrystalline panel, dust deposition tests on the surface of the panels show that the performance of the polycrystalline panel is more affected compared to the performance of the monocrystalline panel. 展开更多
关键词 Solar Pumping Monocrystalline Cell Polycrystalline Cell Dry tropical Zone Dustdeposit
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The Tenth Anniversary of Free Trade Pilot Zones in China:Fundamental Experiences and Enhancement Strategies
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作者 Pei Changhong 《China Economist》 2024年第3期2-20,共19页
Since the 18th National Congress of the Communist Party of China,the country has established 21 Free Trade Pilot Zones(FTZs),achieving significant pioneering results in reform and opening up and creating a strong demo... Since the 18th National Congress of the Communist Party of China,the country has established 21 Free Trade Pilot Zones(FTZs),achieving significant pioneering results in reform and opening up and creating a strong demonstrative effect nationwide.The basic experience from a decade of FTZs includes:adhering to the centralized and unified leadership of the CPC Central Committee;combining top-level design with encouragement of grassroots innovation;leveraging the distinct characteristics and strengths of FTZs to form a differentiated development pattern;maintaining the integration of opening up with domestic reforms;using openness to drive reforms;and organically combining openness with national security assurance.Under the current and future new circumstances,China’s FTZs face new challenges and tasks.In accordance with the directives of the 20th National Congress of the Communist Party of China,an enhancement strategy for the FTZs needs to be implemented.This involves the following:First,accurately understanding and responding to the changing situation to create strategic opportunities.Second,shifting paradigms to implement innovation-driven strategies,using the new development pattern concept to guide the reform experiments and construction of the FTZs.Third,granting more autonomy to FTZs for reforms,pursuing progress while maintaining stability,and solidly advancing the reform experiments in the FTZs.Fourth,orderly expanding the opening up of the service sector and cautiously advancing the internationalization of the renminbi.Fifth,promoting innovative development in trade to build a strong trade nation.Sixth,establishing synergy with bilateral FTZs,Belt and Road cooperation,and national diplomatic strategies to enhance the linkage effect. 展开更多
关键词 Tenth anniversary of Free Trade Pilot zones experience summary enhancement strategy conception
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Research on Disciplines in China’s Local Universities from the Perspective of Special Zones
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作者 Yi Zhang Jiaozhi Wang +1 位作者 Min Wang Jianguo Zhou 《教育技术与创新》 2024年第2期46-58,共13页
China's local colleges and universities are the main force of China's higher education.Due to the limited construction funds,weak discipline foundation and other reasons,China's local colleges and universi... China's local colleges and universities are the main force of China's higher education.Due to the limited construction funds,weak discipline foundation and other reasons,China's local colleges and universities generally face the embarrassment of weak discipline.How to break the constraints of the traditional management system,concentrate and efficiently allocate limited resources to achieve the overall improvement of the discipline construction level,the successful experience of China's special economic zones provides model reference and construction guidance for Chinese local universities.This study takes the subject special zones of local universities in China as the research object,chooses the theoretical system of economics and institutional theory as the logical starting point of the research,constructs the research framework of three dimensions of idea value,system design and action strategy,takes the reform of special economic zones as the institutional model and practice reference,and carries out the research from five dimensions of reform subject,logic,path,idea and strategy.Explore the effective development path of the rise of discipline construction. 展开更多
关键词 local colleges and universities special economic zone special subject zone
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Zones of Openness China’s reforms in its free trade zones offer opportunities to the world
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作者 ZHAO ZHONGXIU KONG QINGFENG ZHU YONGBIAO 《ChinAfrica》 2024年第8期24-25,共2页
Since the 18th National Congress of the Communist Party of China held in 2012,the construction of pilot free trade zone has emerged as a strategically important approach for China’s reform and opening up efforts.Thes... Since the 18th National Congress of the Communist Party of China held in 2012,the construction of pilot free trade zone has emerged as a strategically important approach for China’s reform and opening up efforts.These zones exemplify China’s proactive and open strategy,serving as a key driver for promoting high-quality development.In September 2013,China launched its first pilot free trade zone,China(Shanghai)Pilot Free Trade Zone.Over the past decade,21 additional pilot free trade zones have been established across the country.This expansion has created a comprehensive reform and opening up innovation agenda that spans the eastern,western,southern,northern,and central regions,while integrating coastal,inland,and border areas. 展开更多
关键词 Zone INLAND integrating
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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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Numerical analysis of water-alternating-CO_(2) flooding for CO_(2)-EOR and storage projects in residual oil zones 被引量:1
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作者 Boyu Liu Jun Yao Tunan Sun 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第5期1-11,共11页
Residual oil zones(ROZs)have high residual oil saturation,which can be produced using CO_(2) miscible flooding.At the same time,these zones are good candidates for CO_(2) sequestration.To evaluate the coupled CO_(2)-E... Residual oil zones(ROZs)have high residual oil saturation,which can be produced using CO_(2) miscible flooding.At the same time,these zones are good candidates for CO_(2) sequestration.To evaluate the coupled CO_(2)-EOR and storage perfor-mance in ROZs for Water-Alternating-CO_(2)(WAG)flooding,a multi-compositional CO_(2) miscible model with molecular diffusion was developed.The effects of formation parameters(porosity,permeability,temperature),operation parameters(bottom hole pressure,WAG ratio,pore volume of injected water),and diffusion coeffcient on the coupled CO_(2)-EOR and storage were investigated.Five points from the CO_(2) sequestration curve and the oil recovery factor curve were selected to help better analyze coupled CO_(2)-EOR and storage.The results demonstrate that enhanced performance is observed when formation permeability is higher and a larger volume of water is injected.On the other hand,the performance diminishes with increasing porosity,molecular diffusion of gas,and the WAG ratio.When the temperature is around 100℃,coupled CO_(2)-EOR and storage performance is the worst.To achieve optimal miscible flooding,it is recommended to maintain the bottom hole pressure(BHP)of the injection well above 1.2 minimum miscibility pressure(MMP),while ensuring that the BHP of the production well remains sufficiently high.Furthermore,the tapered WAG flooding strategy proves to be profitable for enhanced oil recovery,as compared to a WAG ratio of 0.5:1,although it may not be as effective for CO_(2) sequestration. 展开更多
关键词 Residual oil zone WAG injection Carbon sequestration Enhanced oil recovery Injection strategies
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Reservoir heterogeneity controls of CO_(2)-EOR and storage potentials in residual oil zones:Insights from numerical simulations 被引量:1
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作者 Yan-Yong Wang Xiao-Guang Wang +4 位作者 Ren-Cheng Dong Wen-Chao Teng Shi-Yuan Zhan Guang-Yong Zeng Cun-Qi Jia 《Petroleum Science》 SCIE EI CSCD 2023年第5期2879-2891,共13页
Residual oil zones(ROZs)have large potential for CO_(2)enhanced oil recovery(EOR)and geologic storage.During CO_(2)injection,the migration of CO_(2)in ROZs controls the performance of both EOR and storage.However,it h... Residual oil zones(ROZs)have large potential for CO_(2)enhanced oil recovery(EOR)and geologic storage.During CO_(2)injection,the migration of CO_(2)in ROZs controls the performance of both EOR and storage.However,it has not been clearly visualized and understood that how geological heterogeneity factors control the transport of CO_(2)in ROZs.In this study,the oil recovery performance and geologic storage potential during continuous CO_(2)injection in a representative ROZ are studied based on geostatistical modelling and high-fidelity three-phase flow simulation.We examined the influence of autocorrelation length of permeability,global heterogeneity(DykstraeParsons coefficient),and permeability anisotropy on cumulative oil recovery and CO_(2)retention fraction.Simulation results indicate that,as the permeability autocorrelation length increases,the cumulative oil recovery and CO_(2)storage efficiency decrease.This results from the accelerated migration of CO_(2)along high permeability zones(i.e.,gas channeling).The increase in global heterogeneity and permeability anisotropies can lead to low oil recovery and poor CO_(2)sequestration performance,depending on the degree of CO_(2)channeling.The net utilization ratio of CO_(2)(CO_(2)retained/oil produced)unfavorably increases with both autocorrelation length and Dykstra eParsons coefficient,but decreases with the increase in kv/kh.Such a decrease is attributed to enlarged swept volume induced by gravity override.The study provides important implications for fieldscale CO_(2)EOR and storage applications in ROZs. 展开更多
关键词 Residual oil zones CO_(2)injection Enhanced oil recovery Geologic sequestration
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Characterizing large-scale weak interlayer shear zones using conditional random field theory 被引量:1
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作者 Gang Han Chuanqing Zhang +5 位作者 Hemant Kumar Singh Rongfei Liu Guan Chen Shuling Huang Hui Zhou Yuting Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第10期2611-2625,共15页
The shear behavior of large-scale weak intercalation shear zones(WISZs)often governs the stability of foundations,rock slopes,and underground structures.However,due to their wide distribution,undulating morphology,com... The shear behavior of large-scale weak intercalation shear zones(WISZs)often governs the stability of foundations,rock slopes,and underground structures.However,due to their wide distribution,undulating morphology,complex fabrics,and varying degrees of contact states,characterizing the shear behavior of natural and complex large-scale WISZs precisely is challenging.This study proposes an analytical method to address this issue,based on geological fieldwork and relevant experimental results.The analytical method utilizes the random field theory and Kriging interpolation technique to simplify the spatial uncertainties of the structural and fabric features for WISZs into the spatial correlation and variability of their mechanical parameters.The Kriging conditional random field of the friction angle of WISZs is embedded in the discrete element software 3DEC,enabling activation analysis of WISZ C2 in the underground caverns of the Baihetan hydropower station.The results indicate that the activation scope of WISZ C2 induced by the excavation of underground caverns is approximately 0.5e1 times the main powerhouse span,showing local activation.Furthermore,the overall safety factor of WISZ C2 follows a normal distribution with an average value of 3.697. 展开更多
关键词 Interlayer shear weakness zone Baihetan hydropower station Conditional random field Kriging interpolation technique Activation analysis
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Variations in Surface Urban Heat Island and Urban Cool Island Intensity:A Review Across Major Climate Zones 被引量:1
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作者 Muhammad Sadiq KHAN Sami ULLAH CHEN Liding 《Chinese Geographical Science》 SCIE CSCD 2023年第6期983-1000,共18页
The climate has an impact on the urban thermal environment,and the magnitude of the surface urban heat island(SUHI)and urban cool island(UCI)vary across the world’s climatic zones.This literature review investigated:... The climate has an impact on the urban thermal environment,and the magnitude of the surface urban heat island(SUHI)and urban cool island(UCI)vary across the world’s climatic zones.This literature review investigated:1)the variations in the SUHI and UCI intensity under different climatic backgrounds,and 2)the effect of vegetation types,landscape composition,urban configuration,and water bodies on the SUHI.The SUHI had a higher intensity in tropical(Af(tropical rainy climate,Köppen climate classification),Am(tropical monsoon climate),subtropical(Cfa,subtropical humid climate),and humid continental(Dwa,semi-humid and semi-arid monsoon climate)climate zones.The magnitude of the UCI was low compared to the SUHI across the climate zones.The cool and dry Mediterranean(Cfb,temperate marine climate;Csb,temperate mediterranean climate;Cfa)and tropical climate(Af)areas had a higher cooling intensity.For cities with a desert climate(BWh,tropical desert climate),a reverse pattern was found.The difference in the SUHI in the night-time was greater than in the daytime for most cities across the climate zones.The extent of green space cooling was related to city size,the adjacent impervious surface,and the local climate.Additionally,the composition of urban landscape elements was more significant than their configuration for sustaining the urban thermal environment.Finally,we identified future research gaps for possible solutions in the context of sustainable urbanization in different climate zones. 展开更多
关键词 urban heat island intensity(SUHI) urban cool island intensity(UCI) day-night surface urban heat island(SUHI) climate zones landscape composition and configuration sustainable urbanization
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Assessing the Impact of Industrial Zones on the Environmental Pollution in Hai Phong’s Coastal Areas, Vietnam
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作者 Pham Thi Song Thu Doan Quang Tri 《Journal of Geoscience and Environment Protection》 2023年第7期11-29,共19页
Pollution in the coastal areas negatively affects biochemical indicators of seawater, human health and marine organisms. Hai Phong is a coastal city of Vietnam with the development of socio-economic activities, repres... Pollution in the coastal areas negatively affects biochemical indicators of seawater, human health and marine organisms. Hai Phong is a coastal city of Vietnam with the development of socio-economic activities, representing through an increasing number of industrial zones. This study is to evaluate the pollution of large industrial zones in Hai Phong city using numerical models. The numerical simulation (MIKE 21 SW, FM, ECO Lab) models were applied to simulate the wave propagation, hydraulic regime, water quality in coastal Hai Phong area. The MIKE 21 ECO Lab model was used to evaluate sources of waste from the large coastal industrial zones to some aquaculture zones. The calibration and validation results of wave propagation and the hydrodynamic models were resonably good, with Nash coefficient ranging from 0.65 to 0.90 and a percent bias (PBIAS) from 5.6% to 9.4%. The simulation results of water quality and concentration of pollutants (DO, BOD<sub>5</sub>, COD, TSS, Fe, and Coliform) in 2023 at the aquaculture locations show that the BOD<sub>5</sub>, COD, and TSS concentrations were higher than the allowable limits stated in the national technical regulation on surface water quality (QCVN 08:2023/BTNMT) and lower than the allowable limits stated in the national technical regulation on marine water quality (QCVN 10:2023/BTNMT). The outcomes of this study will provide more information to support managers to come up with a better socio-economic development plan for Hai Phong city to achieve sustainable development. 展开更多
关键词 Coastal Areas Water Quality MIKE 21 Industrial zones Costal Pollution
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Preservation Potentials of Essential Oils of Ocimum basilicum and Ocimum gratissimum from Two Agro-Ecological Zones on Freshwater Smoke-Dried Oreochromis niloticus Fish Sold in Some Local Markets in Cameroon
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作者 Tsi Celestine Angu Pride Ndasi Ngwasiri +2 位作者 Lifoter Kenneth Navti Diane Youmbi Yimta Fonteh Florence Anyanwe Angaba 《Advances in Biological Chemistry》 2023年第5期192-207,共16页
Dried fish are susceptible to bacteria and fungi attack and are liable to chemical changes which cause losses in quality and reduction of shelf-life. It is important therefore to maintain the quality of fish because c... Dried fish are susceptible to bacteria and fungi attack and are liable to chemical changes which cause losses in quality and reduction of shelf-life. It is important therefore to maintain the quality of fish because continuous consumption of contaminated fish and their products may predispose consumers to health hazards. Maintenance of high quality fish therefore calls for adequate and effective preservation techniques. The study examined the effectiveness of essential oils of Ocimum basilicum and Ocimum gratissimum from two Agro-ecological zones of Cameroon in limiting the microbial proliferation and preserving the quality of smoke-dried Oreochromis niloticus fish stored at 25˚C for two months. The plant materials were harvested from the Western Highlands and Monomodal Humid Forest agroecological zones of Cameroon. Extraction of the essential oil from the plants was done by hydro-distillation. The fish species (Oreochromis niloticus) used in this study was chosen based on a survey study on the most consumed species of freshwater smoke-dried fish in the Western Highlands and Monomodal Humid Forest Agro-ecological zones of Cameroon. Heterotrophic bacteria counts, fungi counts and Enterobacteriaceae counts were used to assess the level heterotrophic bacteria, fungi and Enterobacteriaceae respectively in the fish samples during storage and were done by culture techniques using total plate count agar, potato dextrose agar and violet red bile glucose agar respectively. Total volatile basic nitrogen, peroxide value, and thiobarbituric acid reactive substance assays were used as spoilage indices to assess the nutritional quality of the fish during storage. From the survey study, Oreochromis niloticus was the most consumed smoke-dried fish in the Western Highlands (35.45%) and Monomodal Humid Forest (34.55%) agroecological zones. All the EOs caused a significant reduction in the microbial loads, total volatile basic nitrogen, peroxide value, and thiobarbituric acid reactive substance of smoke-dried Oreochromis niloticus as storage progressed. However, the reduction in these values was more pronounced in samples treated with essential oils of O. gratissimum from the Western Highlands, with heterotrophic bacteria, fungi and Enterobacteriaceae counts being 5.89, 6.97 and 4.59 log<sub>10</sub> cfu/g respectively at the end of the storage period. This was followed by essential oils of O. gratissimum from the Monomodal Humid Forest with heterotrophic bacteria, fungi and Enterobacteriaceae counts being 6.11, 7.79 and 4.86 log<sub>10</sub> cfu/g respectively at the end of the storage period. Also, essential oils of O. gratissimum from the Western Highlands was more effective in preserving the fish quality as lowest total volatile basic nitrogen (12.29 mg/100g), peroxide value (2.79 mEq O<sub>2</sub>·Kg<sup>−1</sup>) and thiobabituric reactive substance (1.695 mg MDA/Kg) values were observed for fish samples treated with this extract at the end of the storage period. This was followed by essential oils of O. gratissimum from the Monomodal Humid Forest with total volatile basic nitrogen (14.95 mgN/100g), Peroxide value (3.23 mEq O<sub>2</sub>·Kg<sup>−1</sup>) and thiobabituric reactive substance (2.354 mg MDA/Kg) at the end of the storage period. From the results obtained, essential oils from O. gratissimum were more effective than that from O. basilicum in the two agroecological zones and should be considered as natural alternative to chemical preservatives for further application in food preservation. 展开更多
关键词 Oreochromis niloticus Essential Oils Fish Quality Ocimum basilicum Ocimum gratissimum Agro-Ecological Zone
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Identification of the Breach of Short-Term Rental Regulations in Irish Rent Pressure Zones
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作者 Guowen Liu Inmaculada Arnedillo-Sánchez Zhenshuo Chen 《Journal of Computer and Communications》 2023年第2期8-19,共12页
The housing crisis in Ireland has rapidly grown in recent years. To make a more significant profit, many landlords are no longer renting out their houses under long-term tenancies but under short-term tenancies. Regul... The housing crisis in Ireland has rapidly grown in recent years. To make a more significant profit, many landlords are no longer renting out their houses under long-term tenancies but under short-term tenancies. Regulating rentals in Rent Pressure Zones with the highest and rising rents is becoming a tricky issue. In this paper, we develop a breach identifier to check short-term rentals located in Rent Pressure Zones with potential breaches only using publicly available data from Airbnb (an online marketplace focused on short-term home-stays) and Irish government websites. First, we use a Residual Neural Network to filter out outdoor landscape photos that negatively impact identifying whether an owner has multiple rentals in a Rent Pressure Zone. Second, a Siamese Neural Network is used to compare the similarity of indoor photos to determine if multiple rental posts correspond to the same residence. Next, we use the Haversine algorithm to locate short-term rentals within a circle centered on the coordinate of a permit. Short-term rentals with a permit will not be restricted. Finally, we improve the occupancy estimation model combined with sentiment analysis, which may provide higher accuracy. 展开更多
关键词 Housing Crisis Short-Term Rental Irish Rent Pressure Zone Image Recognition Breach Identification
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Application of GIS based analytical hierarchy process and multicriteria decision analysis methods to identify groundwater potential zones in Jedeb Watershed, Ethiopia
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作者 Temesgen Mekuriaw Manderso Yitbarek Andualem Mekonnen Tadege Aragaw Worku 《Journal of Groundwater Science and Engineering》 2023年第3期221-236,共16页
The hydrogeological situation of the study area requires the identification of groundwater potential.Remote sensing and satellite data have proven to be reliable tools for understanding various factors that affect gro... The hydrogeological situation of the study area requires the identification of groundwater potential.Remote sensing and satellite data have proven to be reliable tools for understanding various factors that affect groundwater occurrence and movement.This study employed weighted overlay analysis based on satellite imagery and secondary data to create a thematic map for characterizing groundwater potentials in the study area located within Abbay Basin,Ethiopia.Remote sensing(RS)and GIS-based Fuzzy-Analytical Hierarchy Process methods were utilized to classify groundwater potential(GWP)zones into five categories:Very good,good,moderate,poor,and very poor.The central and eastern parts of the study area were identified as having high(33.186%)and very high(2.351%)groundwater potentials,while the western part exhibited poor and very poor potential areas.The groundwater potential map delineated higher and moderate potentials,suitable for installing shallow and production bores.This research demonstrates the effectiveness of RS and GIS techniques for delineating groundwater potential zones,which can aid in the planning and management of groundwater resources.The research findings have the potential to contribute to the formulation of improved groundwater management programs in the study area. 展开更多
关键词 Analytical Hierarchy Process DELINEATION Groundwater potential zones Jedeb Watershed Remote sensing
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