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Formation and ecological response of sand patches in the protection system of Shapotou section of the Baotou-Lanzhou railway,China
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作者 DUN Yaoquan QU Jianjun +4 位作者 KANG Wenyan LI Minlan LIU Bin WANG Tao SHAO Mei 《Journal of Arid Land》 SCIE CSCD 2024年第2期298-313,共16页
The development of bare patches typically signifies a process of ecosystem degradation.Within the protection system of Shapotou section of the Baotou-Lanzhou railway,the extensive emergence of bare sand patches poses ... The development of bare patches typically signifies a process of ecosystem degradation.Within the protection system of Shapotou section of the Baotou-Lanzhou railway,the extensive emergence of bare sand patches poses a threat to both stability and sustainability.However,there is limited knowledge regarding the morphology,dynamic changes,and ecological responses associated with these sand patches.Therefore,we analyzed the formation and development process of sand patches within the protection system and its effects on herbaceous vegetation growth and soil nutrients through field observation,survey,and indoor analysis methods.The results showed that sand patch development can be divided into three stages,i.e.,formation,expansion,and stabilization,which correspond to the initial,actively developing,and semi-fixed sand patches,respectively.The average dimensions of all sand patch erosional areas were found to be 7.72 m in length,3.91 m in width,and 0.32 m in depth.The actively developing sand patches were the largest,and the initial sand patches were the smallest.Throughout the stage of formation and expansion,the herbaceous community composition changed,and the plant density decreased by more than 50.95%.Moreover,the coverage and height of herbaceous plants decreased in the erosional area and slightly increased in the depositional lobe;and the fine particles and nutrients of soils in the erosional area and depositional lobe showed a decreasing trend.In the stabilization phases of sand patches,the area from the inlet to the bottom of sand patches becomes initially covered with crusts.Vegetation and 0-2 cm surface soil condition improved in the erosional area,but this improvement was not yet evident in the depositional lobe.Factors such as disturbance,climate change,and surface resistance to erosion exert notable influences on the formation and dynamics of sand patches.The results can provide evidence for the future treatment of sand patches and the management of the protection system of Shapotou section of the Baotou-Lanzhou railway. 展开更多
关键词 railway protection system sand patch MORPHOLOGY vegetation characteristic soil property
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Computational Strategy Research on the Development of Kiruna,in Sweden
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作者 Ruocheng Sun 《建筑工程(中英文版)》 2024年第1期9-19,共11页
In Kiruna,nearly all the residents support the migration plan in order to make LKAB able to continue the mining process.Based on current condition,a larger part of this town will be demolished by the sinking land caus... In Kiruna,nearly all the residents support the migration plan in order to make LKAB able to continue the mining process.Based on current condition,a larger part of this town will be demolished by the sinking land caused by iron ore mining processing operated by LKAB.Since then,most of the buildings in the sinking district will be relocated in another district.However,the situation in Kiruna is not quite the same as when this kind of migration happens in another place.In other place,while migration happens,even if not most,a large part of the local residents will resist and fight for their house and properties.Concentrated on the ownership of different buildings and tried find the relationship between the public and private buildings to discover some issue that will help to work on the computational urban design. 展开更多
关键词 Iron Mine Economic PUBLIC PRIVATE Property OWNERSHIP TRANSPORTATION EMPLOYMENT Economical System development History Swarm Intelligence Logic Processing
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Integration of Transport and Land Use Planning by Transit-Oriented Development for Economic Sustainability of the Standard Gauge Railway Projects in Tanzania
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作者 Emmanuel Elifadhili Mchome Uwezo Wilbard Nzoya 《Journal of Transportation Technologies》 2023年第4期756-771,共16页
Tanzania is one of the countries in Africa that has engaged in the projects for construction of the electrified Standard Gauge Railway (SGR). However, lack of integration of transportation and land-use planning threat... Tanzania is one of the countries in Africa that has engaged in the projects for construction of the electrified Standard Gauge Railway (SGR). However, lack of integration of transportation and land-use planning threatens economic sustainability of the SGR project. This study was carried out for the purpose of finding-out how transportation can be integrated with land-use planning for economic sustainability of the project. The study was carried-out by using qualitative research approach through demonstration as case study. Findings show that construction of the SGR is not integrated with land-use planning around the stations and along the SGR corridor. It is concluded that economic sustainability of the SGR projects can be achieved by integration of transport and land-use planning. As demonstrated, it is recommended to deliberate for integration of transportation and land-use planning in the SGR projects of which the prime land within Transit Stations can be efficiently used by using Transit Oriented Development and secure more land for production activities around the Transit Stations and along the SGR corridor. 展开更多
关键词 Economic Sustainability Standard Gauge railway Land Planning Transit-Oriented development SGR Transit Stations
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Intellectual Property Protection and High-Quality Development of Xinjiang Melons under the Big Food Concept
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作者 Miaomiao XU Yulan BAI +3 位作者 Jinjin WANG Yuanpeng SUN Jin ZENG Zhiguo SUN 《Asian Agricultural Research》 2023年第8期1-7,共7页
The development of diversified foods such as melons under the big food concept can reduce the pressure on staple food grain.Xinjiang has the advantages of building a new development pattern of dual circulation of dive... The development of diversified foods such as melons under the big food concept can reduce the pressure on staple food grain.Xinjiang has the advantages of building a new development pattern of dual circulation of diversified food industry and establishing a national diversified food safety and high-quality assurance center.The construction of an agricultural power needs the strategic support of an intellectual property power.This paper introduced and studied Xinjiang s melon industry and its agricultural intellectual property resources,analyzed the six main problems,including many idle land resources have not been developed into melon fields and the role of melons in diversified food supply systems not well played.Finally,it proposed to vigorously develop diversified food industries such as melons in Xinjiang and establish an eight-point strategy such as national diversified food safety and high-quality assurance center. 展开更多
关键词 Big food concept Strategy of building an intellectual property power MELON Intellectual property INHERITANCE Innovation and development Xinjiang
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Current situation and development trend of design methods for subgrade structure of high speed railways
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作者 Yangsheng Ye Degou Cai +3 位作者 Qianli Zhang Shaowei Wei Hongye Yan Lin Geng 《Railway Sciences》 2023年第3期289-309,共21页
Purpose–This method will become a new development trend in subgrade structure design for high speed railways.Design/methodology/approach–This paper summarizes the structural types and design methods of subgrade bed ... Purpose–This method will become a new development trend in subgrade structure design for high speed railways.Design/methodology/approach–This paper summarizes the structural types and design methods of subgrade bed for high speed railways in China,Japan,France,Germany,the United States and other countries based on the study and analysis of existing literature and combined with the research results and practices of high speed railway subgrade engineering at home and abroad.Findings–It is found that in foreign countries,the layered reinforced structure is generally adopted for the subgrade bed of high speed railways,and the unified double-layer or multi-layer structure is adopted for the surface layer of subgrade bed,while the simple structure is adopted in China;in foreign countries,different inspection parameters are adopted to evaluate the compaction state of fillers according to their respective understanding and practice,while in China,compaction coefficient,subsoil coefficient and dynamic deformation modulus are adopted for such evaluation;in foreign countries,the subgrade top deformation control method,the subgrade bottom deformation control method,the subsurface fill strength control method are mainly adopted in subgrade bed structure design of high speed railways,while in China,dynamic deformation control of subgrade surface and dynamic strain control of subgrade bed bottom layer is adopted in the design.However,the cumulative deformation of subgrade caused by train cyclic vibration load is not considered in the existing design methods.Originality/value–This paper introduces a new subgrade structure design method based on whole-process dynamics analysis that meets subgrade functional requirements and is established on the basis of the existing research at home and abroad on prediction methods for cumulative deformation of subgrade soil. 展开更多
关键词 High speed railway Subgrade engineering Subgrade bed structure Design method Existing research development trend
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Development and psychometric properties of the Malaysian elder abuse scale
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作者 Tengku Aizan Hamid Yadollah Abolfathi Momtaz +4 位作者 Rahimah Ibrahim Mariani Mansor Asnarulkhadi Abu Samah Nurizan Yahaya Siti Farra Zillah Abdullah 《Open Journal of Psychiatry》 2013年第3期283-289,共7页
Elder abuse is an emerging issue of serious concern with life-threatening consequences. This study aimed to develop and assess the validity and reliability of a new scale to assess elder abuse. A cross-sectional multi... Elder abuse is an emerging issue of serious concern with life-threatening consequences. This study aimed to develop and assess the validity and reliability of a new scale to assess elder abuse. A cross-sectional multistage sampling technique was used to obtain a nationally representative sample of older Malaysians. The iterative development process resulted in a 16-item, four-dimension scale. Exploratory factor analysis yielded a 10-item scale with three factors. The value of Cronbach’s alpha for total scale and its subscales indicated sufficient internal consistency. Multitrait scaling analysis also showed good convergent and discriminant validity. Furthermore, predictive validity of the proposed scale was established by demonstrating a statistically significant association between elder abuse and depression through multiple logistic regression analysis. The findings from this study demonstrate an acceptable level of validity and reliability for new scale. This scale can be used by health and social care workers to identify elder abuse cases. 展开更多
关键词 ELDER ABUSE Elderly PSYCHOMETRIC properties SCALE development
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Intellectual Property Protection and High-quality Development of Grape Industrial Clusters in Xinjiang 被引量:2
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作者 Miaomiao XU Jinjin WANG +3 位作者 Yulan BAI Jin ZENG Yuanpeng SUN Zhiguo SUN 《Asian Agricultural Research》 2023年第5期1-7,共7页
This paper introduced the grape industry in Xinjiang and its agricultural intellectual property resources,and analyzed six major problems such as the ineffective leading role of intellectual property rights in high-qu... This paper introduced the grape industry in Xinjiang and its agricultural intellectual property resources,and analyzed six major problems such as the ineffective leading role of intellectual property rights in high-quality development.Finally,it proposed eight strategies to build a national-level regional fine-grain breeding base for grapes and develop“agricultural chips”in the context of the strategy of strengthening the country with intellectual property and innovation-driven development strategy. 展开更多
关键词 GRAPE Industrial clusters Intellectual property High-quality development XINJIANG
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Intellectual Property Protection and New Development Pattern Construction of Xinjiang Jujube 被引量:2
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作者 Miaomiao XU Yulan BAI +3 位作者 Jinjin WANG Yuanpeng SUN Jin ZENG Zhiguo SUN 《Asian Agricultural Research》 2023年第7期1-8,共8页
"Three new developments"is the guiding ideology of Chinese-style high-quality development in the new era.Jujube(Zizyphus jujube Mill.)is a plant of Zizyphus of Rhamnaceae,which originated in China and has be... "Three new developments"is the guiding ideology of Chinese-style high-quality development in the new era.Jujube(Zizyphus jujube Mill.)is a plant of Zizyphus of Rhamnaceae,which originated in China and has been listed as one of the"five fruits"since ancient times.Xinjiang is the most important jujube producing area in China,and its yield has accounted for 50%of the national jujube yield.In the five prefectures and cities of southern Xinjiang,as well as the regimental farms of southern and eastern Xinjiang of Xinjiang Production and Construction Corps,the jujube industry is an advantageous characteristic industry in agriculture.This paper studied Xinjiang jujube industry and its agricultural intellectual property resources,analyzed six major issues to be further implemented,such as the"three new developments"thinking and the strategy of building an intellectual property power,and puts forward eight strategies such as coordinating the two markets and two resources to accelerate the construction of a new development pattern and dual circulation of jujube. 展开更多
关键词 Jujube(Zizyphus jujube Mill.) FRUIT Intellectual property New development pattern XINJIANG
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RESEARCH AND DEVELOPMENT OF VIRTUAL PROTOTYPE OF RUNNING GEARS FOR RAILWAY VEHICLE 被引量:6
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作者 ZOU Yisheng DING Guofu +2 位作者 ZHANG Weihua XU Mingheng HE Yong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第1期36-41,共6页
Virtual prototype is an important idea to resolve design problems of railway vehicle. A different development method, which is based on national product and autonomous development, and would like to reflect the specia... Virtual prototype is an important idea to resolve design problems of railway vehicle. A different development method, which is based on national product and autonomous development, and would like to reflect the specialty of railway vehicle development in China, is presented. According to the developing process of railway vehicle, the research contents and developing method are pointed out. The integration between CAD and performance analysis software on dynamics and strength is mainly considered. In CAD environment, the properties for dynamics computing are extracted directly from the model and exported with model. This method can avoid data losing caused by model rebuilding in CAE software, and increase the direct dependence of product CAD. Then the vehicle model with properties will be used for real-time dynamics and kinematics analysis and simulation. Therefore, the strength of the parts can be analyzed. The results of dynamics and strength analysis will be fed back to optimize the design model. All operations are dispatched by a control platform, and all data are managed according to the principle of PDM. Testing results show this method is correct. 展开更多
关键词 Virtual prototype railway vehicle Property extraction Dynamics analysis Strength analysis
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Texture development and tensile properties of Mg?Yb binary alloys during hot extrusion and subsequent annealing 被引量:4
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作者 Lu Li Cuncai Zhang +3 位作者 Hao Lv Chunrong Liu Zhuozhang Wen Jingwen Jiang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第1期267-283,共17页
Ytterbium(Yb)containing magnesium alloys have aroused extensive interest due to their excellent mechanical properties after thermomechanical processing and heat treatment.Unfortunately,the sole effect of Yb addition o... Ytterbium(Yb)containing magnesium alloys have aroused extensive interest due to their excellent mechanical properties after thermomechanical processing and heat treatment.Unfortunately,the sole effect of Yb addition on the microstructure and mechanical properties of pure Mg matrix remains uncertain to date.In this work,the effects of Yb concentration on the texture development and tensile properties of pure Mg matrix during hot extrusion and the subsequent annealing were systematically investigated.The results revealed that the constitutional supercooling induced by Yb addition refined the as-cast microstructure but exerted a negligible effect on the original columnar grain morphology.When extruded at 300°C,the dynamic recrystallization(DRX)process was considerably retarded.The in-grain misorientation axes(IGMA)analysis combined with TEM observation indicated that non-basal slips operated with increasing Yb concentration.Specifically,the prismaticslip should be robustly activated in Mg-1.0 Yb extrudate,promoting the formation of the texture with{10?10}plane normal to the extrusion direction(ED),while for the Mg?2.0 Yb counterpart,the increased activity of pyramidal<c+a>slip and the relaxation of basal/<c+a>dislocations generated an ED-tilted texture component.The preferential grain growth dominated the subsequent annealing texture development at 400°C when a comparable grain size was achieved.An obvious ED-tilted texture intensity with the peak around<12 13>was observed in Mg-2.0 Yb alloy,which was primarily caused by grains with the basal orientation vanished and with the non-basal orientations intensified due to a higher concentration of Yb solute.Favored by the grain refinement,the Mg-2.0 Yb extrudate exhibited a high tensile yield strength of 304±3.5 MPa,while the subsequently annealed counterpart presented a favorable elongation to failure of 14.8±1.2%,which mainly due to the homogeneous grain structure,weak ED-tilted texture,and dissolution of coarse phases after high-temperature annealing. 展开更多
关键词 Magnesium alloy YTTERBIUM Texture development Tensile properties
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Application and development in railway vehicles trend of new welding technologies manufacturing industry 被引量:5
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作者 王春生 刘杰 +1 位作者 王洪潇 段珍珍 《China Welding》 EI CAS 2015年第4期9-14,共6页
This paper introduces the application of new automatic welding technologies in railway vehicles manufacturing industry, and presents the state of art of advanced friction stir welding technology, semi-penetration lase... This paper introduces the application of new automatic welding technologies in railway vehicles manufacturing industry, and presents the state of art of advanced friction stir welding technology, semi-penetration laser welding technology and laser-arc hybrid welding technology in manufacturing aluminum alloy body shell, stainless steel body shell and bogie. This paper also analyzes the application and development trend of three welding technologies in the future. 展开更多
关键词 railway vehicles friction stir welding semi-penetration laser welding laser-arc hybrid welding development trend
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The role of the Mg_(17)Al_(12)-phase in the high-pressure die-cast magnesium-aluminum alloy system
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作者 J.P.Weiler 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第11期4235-4246,共12页
The Mg_(17)Al_(12)β-phase is highly influential to the performance of magnesium-aluminum high-pressure die-casting alloys. Numerous studies have investigated the effect of this phase on the room temperature and eleva... The Mg_(17)Al_(12)β-phase is highly influential to the performance of magnesium-aluminum high-pressure die-casting alloys. Numerous studies have investigated the effect of this phase on the room temperature and elevated-temperature mechanical properties as well as the corrosion,flammability, thermal conductivity and castability performance. This work summarizes the results of these works, as well as the studies that describe control of the Mg_(17)Al_(12)-phase through alloying additions that modify the microstructure and resulting alloy performance. The results of this work can be used as a basis for the development of alloying additions that enable modifications to the performance of high-pressure die-cast magnesium-aluminum-based alloys. 展开更多
关键词 Magnesium alloys HPDC Alloy development properties
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Construction of China Osmanthus City and Intellectual Property Right Protection in Xianning City in the Context of Three New Developments 被引量:12
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作者 Li GAO Zhiguo SUN +2 位作者 Yueqiu HE Jiandong LAI Hongguo CHEN 《Asian Agricultural Research》 2022年第9期1-6,15,共7页
Xianning City of Hubei Province is one of the five major traditional osmanthus producing areas in the world and the hometown of osmanthus in China. Xianning is constructing China Osmanthus City in the whole city. This... Xianning City of Hubei Province is one of the five major traditional osmanthus producing areas in the world and the hometown of osmanthus in China. Xianning is constructing China Osmanthus City in the whole city. This paper first introduces the main characteristics of the osmanthus industry in Xianning City, and analyzes the characteristics of traditional knowledge, biological genetic resources, new plant varieties, patents, geographical indications, and trademarks. Then, it studies the intellectual property resources of the osmanthus industry, and analyzes the main problems existing in the construction of China Osmanthus City and intellectual property right protection. Finally, it comes up with constructive recommendations including applying for China and Globally Important Agricultural Heritage Systems, developing colored-leaf osmanthus varieties, creating a regional public brand of osmanthus specialty products, and building a new development pattern of osmanthus industry. 展开更多
关键词 China Osmanthus City Three new developments(new development stage philosophy and paradigm) OSMANTHUS Intellectual property right High-quality development
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Design and Development of Composite Plywood that Integrates Fire Resistance,Water Resistance and Wear Resistance
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作者 Xingyu Liang Xiaoyu Gu +4 位作者 Myint Myint Paing Hsu Yuhang He Rongzhuo Zhang Conghui Cai Zheng Wang 《Journal of Renewable Materials》 SCIE EI 2023年第5期2333-2344,共12页
In order to improve the fire resistance,water resistance and wear resistance of ordinary plywood products in the wood processing industry,three composite structures of plywood products S1,S2 and S3 were designed in th... In order to improve the fire resistance,water resistance and wear resistance of ordinary plywood products in the wood processing industry,three composite structures of plywood products S1,S2 and S3 were designed in this paper,and a reasonable production process was proposed.Through the physical and mechanical properties and fire resistance testing and technical and economic analysis,the applicability of composite plywood was evaluated.The results of the study showed that the physical mechanics of the three kinds of composite structure plywood met the standard requirements,and their fire resistance was far better than that of ordinary plywood.Among them,the S1 structural board had the best overall physical and mechanical properties.The S3 structural board showed the best fire resistance,which was about 1.9 times more than that of ordinary plywood,and the added cost was the lowest.The thin cork board added to the S2 structural board had poor fire performance since the air in the cork board cavities had a certain combustion-supporting effect,which inhibited the fire resistance of high-pressure laminate(HPL)layer.Moreover,the additional cost of the S2 board was the highest,and its comprehensive performance was the worst.The S3 structural plywood product composed of HPL fireproof board with a thickness of about 1 mm in the surface layer and ordinary plywood with a thickness of about 12 mm in the core layer was the most cost-effective product,which could meet the needs of various fields such as construction,home furnishing,decoration and transportation. 展开更多
关键词 Wear resistance PLYWOOD structural design and development physical and mechanical properties fire resistance
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Development on manufacturing technology of railway locomotive and rolling stock industry in China 被引量:1
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作者 WANG Kejia (China National Railway Locomotive and Rolling-Stock Industry Corporation (100844 ))SUN Shuangjin (Changchun Railway Car Works) 《China Welding》 EI CAS 1994年第2期151-156,共6页
This paper described progress and development on the welding technology and vehicle manufacture during last decade, which promoted the technical progress for development and creation a considerable variety of high qua... This paper described progress and development on the welding technology and vehicle manufacture during last decade, which promoted the technical progress for development and creation a considerable variety of high quality products in railway locomotive and rolling stock industry. 展开更多
关键词 MANUFACTURING development railway TECHNOLOGY INDUSTRY
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KL-SG High-Speed Rail-a catalyst for national economic development Sri Viknesh Permalu and Karthigesu Nagarajoo
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作者 Sri Viknesh Permalu Karthigesu Nagarajoo 《Railway Sciences》 2024年第3期265-278,共14页
Purpose-In an increasingly interconnected world,transportation infrastructure has emerged as a critical determinant of economic growth and global competitiveness.High-speed rail(HSR),characterized by its exceptional s... Purpose-In an increasingly interconnected world,transportation infrastructure has emerged as a critical determinant of economic growth and global competitiveness.High-speed rail(HSR),characterized by its exceptional speed and efficiency,has garnered widespread attention as a transformative mode of transportation that transcends borders and fosters economic development.The Kuala Lumpur-Singapore(KL-SG)HSR project stands as a prominent exemplar of this paradigm,symbolizing the potential of HSR to serve as a catalyst for national economic advancement.Design/methodologylapproach-This paper is prepared to provide an insight into the benefits and advantages of HSR based on proven case studies and references from global HSRs,including China,Spain,France and Japan.Findings-The findings that have been obtained focus on enhanced connectivity and accessibility,attracting foreign direct investment,revitalizing regional economies,urban development and city regeneration,boosting tourism and cultural exchange,human capital development,regionai integration and environmental and sustainability benefits.Originality/value-The KL-SG HSR,linking Kuala Lumpur and Singapore,epitomizes the potential for HSR to be a transformative agent in the realm of economic development.This project encapsulates the aspirations of two dynamic Southeast Asian economies,united in their pursuit of sustainable growth,enhanced connectivity and global competitiveness.By scrutinizing the KLSG High-Speed Rail through the lens of economic benchmarking,a deeper understanding emerges of how such projects can drive progress in areas such as cross-border trade,tourism,urban development and technological innovation. 展开更多
关键词 High-speed rail TRANSPORTATION railways Sustainable mobility Socioeconomic development Technology Papertype Case study
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The Yoruba version of LittlEARS Auditory Questionnaire: Evaluation of auditory development in children with normal hearing
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作者 Olawunmi Kayode Adebolajo A.Adeyemo 《Journal of Otology》 CSCD 2018年第3期92-96,共5页
The goal of this study was to translate the LittlEARS Auditory Questionnaire into Yoruba language for use with Yoruba-speaking parents and to evaluate the psychometric properties of the Yoruba version of questionnaire... The goal of this study was to translate the LittlEARS Auditory Questionnaire into Yoruba language for use with Yoruba-speaking parents and to evaluate the psychometric properties of the Yoruba version of questionnaire. Translation of the LittlEARS Auditory Questionnaire into Yoruba language was done using a back-translation method. The study participants included 423 parents of normal hearing children aged6 e24 months. Psychometric analyses(scale analysis and item analysis) of the translated questionnaire was done. The scale characteristics in the dataset are: Internal consistency: Cronbach's alpha?0.907;reliability; Split-half?0.701; predictive accuracy; Guttman's lambda?0.583; correlation between total score and children's age?0.783. The regression analysis showed that 75.3% of the variance in the total scores can be explained by age. The Yoruba version of the LittlEARS Auditory Questionnaire is a dependable and valid tool as evidenced by the results of psychometric analyses. The tool is useful for assessing auditory development in children between 6 and 24 months of age. 展开更多
关键词 AUDITORY development HEARING LOSS LittlEARS AUDITORY QUESTIONNAIRE PSYCHOMETRIC properties
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Optimal allocation of land resources in the process of economic development
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作者 LIN Qing 《Ecological Economy》 2015年第4期313-321,共9页
In this paper,the writer uses a mathematical model to analyze:a theoretical model of land resources optimal allocation with the constraint of sustainable development;equilibrium and defects of land resources allocatio... In this paper,the writer uses a mathematical model to analyze:a theoretical model of land resources optimal allocation with the constraint of sustainable development;equilibrium and defects of land resources allocation in a competitive market;and how effective governmental supervision can change the equilibrium in the market and promote the optimization of land resources allocation.The main points of this paper are:continuous and excessive conversions that change land resources from agricultural use to non-agricultural use in the process of economic development are economic rules;a competitive market is an important way to improve the efficiency of land resources allocation;effective governmental supervision can cover the shortage of market and promote the optimization of land resources allocation;a reasonable arrangement of land property rights can reduce the transaction costs of government management in optimizing land resources allocation;and,the targets of land resources optimal allocation are developing along with economic development. 展开更多
关键词 economic development PROCESS LAND resources optimal ALLOCATION sustainable development LAND property RIGHTS
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High-Speed EMUs:Characteristics of Technological Development and Trends 被引量:15
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作者 Hongwei Zhao Jianying Liang Changqing Liu 《Engineering》 SCIE EI 2020年第3期234-244,共11页
1.A worldwide history of high-speed trains High-speed railway(HSR)is defined by the International Union of Railways(UIC)as new lines with design speeds above 250 kmh1 and upgraded existing lines with speeds of up to 2... 1.A worldwide history of high-speed trains High-speed railway(HSR)is defined by the International Union of Railways(UIC)as new lines with design speeds above 250 kmh1 and upgraded existing lines with speeds of up to 200 kmh1[1].In China,HSR is defined as new passenger-dedicated lines designed for electric multiple unit(EMU)trains running at a speed of 250 kmh1 or above(actual or reserved),with an initial operation speed not lower than 200 kmh1[2].The worldwide development of HSRs and high-speed EMUs can be roughly divided into three stages:initial operation,line platform expansion,and rapid development. 展开更多
关键词 development. railway PASSENGER
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Development and application of titanium alloy casting technology in China 被引量:5
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作者 NAN Hai XIE Cheng-mu ZHAO Jia-qi 《China Foundry》 SCIE CAS 2005年第4期239-245,共7页
The development and research of titanium cast alloy and its casting technology, especially its application in aeronautical industry in China are presented. The technology of molding, melting and casting of titanium al... The development and research of titanium cast alloy and its casting technology, especially its application in aeronautical industry in China are presented. The technology of molding, melting and casting of titanium alloy, casting quality control are introduced. The existing problems and development trend in titanium alloy casting technology are also discussed. 展开更多
关键词 steel CASTINGS inserted die microstructure mechanical properties flame QUENCHING cast titanium alloy CASTING technology quality control development TREND
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