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Study on Rural Solid Waste Collection and Transportation Mode and Route Optimization Strategy in the Cold Regions of Northern China
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作者 Li Chuan-gang Liu Peng +1 位作者 Xu Hui Ma Li 《Journal of Northeast Agricultural University(English Edition)》 2023年第4期75-88,共14页
Rural vitalization is a major strategy for reform and development of agriculture and rural areas in China,the key task of which is improving rural living environment.Imperfect rural solid waste(RSW)collection and tran... Rural vitalization is a major strategy for reform and development of agriculture and rural areas in China,the key task of which is improving rural living environment.Imperfect rural solid waste(RSW)collection and transportation system exacerbates the pollution of RSW to rural living environment,while it has not been established and improved in the cold region of Northern China due to climate and economy.Through the analysis of the current situation of RSW source separation,collection,transportation and disposal in China,an RSW collection and transportation system suitable for the northern cold region was developed.Considering the low winter temperature in the northern cold region,different requirements for RSW collection,transportation and terminal disposal,scattered source points and single terminal disposal nodes in rural areas,the study focused on determining the number and location of transfer stations,established a model for transfer stations selection and RSW collection and transportation routes optimization for RSW collection and transportation system,and proposed the elite retention particle swarm optimization–genetic algorithm(ERPSO–GA).The rural area of Baiquan County was taken as a representative case,the collection and transportation scheme of which was given,and the feasibility of the scheme was clarified by simulation experiment. 展开更多
关键词 rural solid waste(RSW) collection and transportation route optimization rural environment collection and transportation costs elite retention particle swarm optimization-genetic algorithm(ERPSO-GA)
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Combinations of Transportation Policies to Promote BRT Usage Using Artificial Society Model
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作者 Hiroaki Inokuchi 《Journal of Traffic and Transportation Engineering》 2024年第1期1-10,共10页
Various transportation systems have been developed in recent years.In this study,an artificial society model is developed to examine the combination of transportation policies in urban areas.In this model,each trip ma... Various transportation systems have been developed in recent years.In this study,an artificial society model is developed to examine the combination of transportation policies in urban areas.In this model,each trip maker selects the primary and terminal transportation modes.An artificial society model is applied to the southeastern region of Osaka City,Japan.The effects of introducing BRT(bus rapid transit,primary transportation)and on-demand buses(terminal transportation)are investigated.The results confirm that BRT is used by a certain number of users.An increase in the use of BRT will increase the amount of walking,thus resulting in a healthy city.However,on-demand buses are rarely used as terminal transportation.Additionally,the development of bicycle parking stations near BRT stops is shown to be effective in the northern section of the BRT route. 展开更多
关键词 Artificial society model bus rapid transit on-demand bus transportation policy.
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Current Status of Sludge Collection, Transportation and Treatment in Ho Chi Minh City 被引量:1
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作者 Nguyen Trung Viet Tran Thi My Dieu Nguyen Thi Phuong Loan 《Journal of Environmental Protection》 2013年第12期1329-1335,共7页
In the process of construction and development, Ho Chi Minh City is discharging about six types of sludge: 1) sludge from urban wastewater drainage systems;2) sludge from industrial wastewater drainage system;3) sludg... In the process of construction and development, Ho Chi Minh City is discharging about six types of sludge: 1) sludge from urban wastewater drainage systems;2) sludge from industrial wastewater drainage system;3) sludge from the canal dredging activities periodically;4) sludge from septic tanks;5) sludge from the water treatment station/plant;6) sludge from the construction sites. Sludge’s components are very different among types of sludge, sludge from the sewer network and canal dredging contain mainly sand and soil (70% - 90% dry weight), while the sludge from the wastewater/water treatment station/plant and from septic tanks contain mainly biodegradable organic substances (55% - 80% dry weight). The concentrations of all above-mentioned sludge (except sludge from the hazardous industrial wastewater treatment plant) are lower than toxic threshold. The volume of total sludge is about 3000 - 4000 m3/day (5000 - 6000 tons/day), excepting the amount of sludge generated from the water treatment plant (which is collected and treated separately). Sludge from wastewater treatment plants and septic tanks is collected, transported and recycled to become organic fertilizer. The other types of sludge are collected, transported, and disposed at the “unknown” locations, even though they have different values for use. 展开更多
关键词 SLUDGE SLUDGE collection SLUDGE transportation SLUDGE Treatment SLUDGE Management
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Establishment and application of performance evaluation model for collection and transportation system of municipal solid waste
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作者 彭绪亚 林晓东 +2 位作者 贾传兴 王渝昆 黄媛媛 《Journal of Central South University》 SCIE EI CAS 2009年第S1期351-356,共6页
On the basis of analyzing the typical waste collection and transportation mode,the evaluation index system for performance of the waste collection and transportation system was proposed with three grades,which related... On the basis of analyzing the typical waste collection and transportation mode,the evaluation index system for performance of the waste collection and transportation system was proposed with three grades,which related to six factors,such as economic evaluation,high efficient evaluation,environmental impact assessment,resource evaluation,evaluation of security and emergency,evaluation of management and society. With the performance evaluation theory,the performance evaluation model of waste collection and transportation system was constructed,which quantified the grading standard of index and determined the index weight in analytic hierarchy process (AHP). After evaluating the waste collection and transportation system of the main districts of Chongqing city,the results show that the it has an excellent performance evaluation grade with very high performance level of three indices involving evaluation of management and society,environmental impact assessment,evaluation of security and emergency and quite low performance level of two indices that include high efficient evaluation and economic evaluation. 展开更多
关键词 MUNICIPAL solid waste collection and transportation SYSTEM performance evaluation index SYSTEM ANALYTIC HIERARCHY process
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Adding Sputum Collection and Transportation Services for Early Identification TB Cases in Hard-to-Reach Difficult Terrain—Will It Help?
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作者 Badri Thapa Banuru Muralidhara Prasad +3 位作者 Sarabjit Singh Chadha Subrat Mohanty Deepak R. Mishra Jamie Tonsing 《Journal of Tuberculosis Research》 2017年第4期220-228,共9页
A community engagement project was designed and implemented to reach 10.6 million population in 13 districts of Uttarakhand state—India, to identify presumptive TB patients (PTBPs) and link to free diagnostics servic... A community engagement project was designed and implemented to reach 10.6 million population in 13 districts of Uttarakhand state—India, to identify presumptive TB patients (PTBPs) and link to free diagnostics services, either through referral or sputum collection and transportation (SCT). The objective of this study is to determine additional yield of TB patients achieved by providing SCT services in comparison to referrals of PTBPs identified in hard-to-reach areas. This was before and after comparative study conducted between April-June 2014 (2Q2014-before) to July-September 2014 (3Q2014-after). SCT was advised for all PTBPs identified from community level interventions between July-September 2014 (3Q2014-after). In 3Q2014, additional 279 (34%) PTBPs were examined in the microscopy centre with an additional 36 (51%) new smear positive (NSP) patient diagnosed. A total of 46 NSP (128%) were contributed by SCT alone. Higher proportion (94%) of TB patients was initiated on treatment in 3Q2014 in comparison to 2Q2014 (91%). SCT as a strategy for early case detection in hard-to-reach difficult terrain yields positive results in comparison to mere referral of PTBPs. 展开更多
关键词 Hard-to-Reach SPUTUM collection and transportation India TUBERCULOSIS Project Axshya
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Transportation Development Transition in China 被引量:5
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作者 JIN Fengjun DING Jinxue +2 位作者 WANG Jiao'e LIU Dong WANG Chengjin 《Chinese Geographical Science》 SCIE CSCD 2012年第3期319-333,共15页
Scientific development is an invaluable asset to a country.Policies and development modes should be carried out based on scientific findings not only in industry,but also in transportation infrastructure construction.... Scientific development is an invaluable asset to a country.Policies and development modes should be carried out based on scientific findings not only in industry,but also in transportation infrastructure construction.Building an integrated transportation system,which is in line with the national requirements of China and supports sustainable socio-economic development,is a key strategic issue related to building a moderately prosperous society and achieving realistic goals of a medium-level developed country.Based on a systematic review of the advances in China's transportation infrastructure over the last 60 years,this paper explores the main drivers of transportation development,including national policy,transportation structure,investment efficiency,and technological innovation.Analysis shows that China's comprehensive transportation infrastructure construction since 1949 can be divided into five stages initiated by these drivers,which correspond to four transition modes:policy transition,structural transition,efficiency transition,and technology transition.The transition path of China's transportation development shows that the dominant factors have changed,and the interval for each transition has shortened.With the implementation of the '12th Five-Year Plan',China's transportation infrastructure construction is showing some new characteristics and facing a new development transition.Finally,this paper analyzes the trends in transportation development in China and concludes that technological innovation will be the main driving force to increase the transportation supply and service area in the future. 展开更多
关键词 交通运输结构 中国 交通基础设施建设 综合运输体系 中等发达国家 技术创新 综合交通运输 交通发展
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Users’ Perception on Operation and Performance of Public Transport Systems in African Developing Countries: The Case of Bus Rapid Transit (BRT) in Dar es Salaam City, Tanzania
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作者 Emmanuel Elifadhili Mchome Uwezo Wilbard Nzoya 《Open Journal of Applied Sciences》 2023年第12期2408-2420,共13页
Public transport system has been a means of addressing transportation challenges in urban areas, such as traffic congestion, traffic jam and long travel time in cities worldwide. Transportation in Africa is unique in ... Public transport system has been a means of addressing transportation challenges in urban areas, such as traffic congestion, traffic jam and long travel time in cities worldwide. Transportation in Africa is unique in that it has the least developed public transport systems in the world, while also being one of the fastest urbanizing continents. Bus Rapid Transit being one of the public transport systems was introduced in Africa in 2008 as a means to provide solution on urban transportation challenges. Despite of public transport being the main means of transport in African developing countries, there have been a number of challenges that affects efficiency of performance of the system and makes its users uncomfortable. Therefore, the study aimed at exploring the setbacks or challenges associated with operation and performance of the BRT system in the African developing countries and address them. The study employed mixed methods research design that integrates both qualitative and quantitative data collection methods and analysis. The study findings reveal that, there is an improvement on the perspectives of the commuters on public transport after introduction of BRT system. However, some challenges such as long waiting time, passengers overcrowding during peak hours, as well as safety and security can slowly change the perspective of the commuters. Therefore, to address these challenges it is recommended to reduce the long waiting time and improve accessibility by introduction of passenger information displays (bus information system) and automated fare collection system;reduce travel time by introduction of bus priority signal;and improve safety and security by introduction of signage and CCTV Camera within the bus and bus stops. 展开更多
关键词 Bus Rapid transit Commuters’ Perception Public transport System
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Seasonal Transition Features of Large-Scale Moisture Transport in the Asian-Australian Monsoon Region 被引量:22
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作者 何金海 孙丞虎 +2 位作者 刘芸芸 Jun MATSUMOTO 李维京 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第1期1-14,共14页
Using NCEP/NCAR reanalysis data for the period of 1957-2001, the climatological seasonal transition features of large-scale vertically integrated moisture transport (VIMT) in the Asian-Australian monsoon region are ... Using NCEP/NCAR reanalysis data for the period of 1957-2001, the climatological seasonal transition features of large-scale vertically integrated moisture transport (VIMT) in the Asian-Australian monsoon region are investigated in this paper. The basic features of the seasonal transition of VIMT from winter to summer are the establishment of the summertime "great moisture river" pattern (named the GMR pattern) and its eastward expansion, associated with a series of climatological events which occurred in some "key periods", which include the occurrence of the notable southerly VIMT over the Indochina Peninsula in mid March, the activity of the low VIMT vortex around Sri Lanka in late April, and the onset of the South China Sea summer monsoon in mid May, among others. However, during the transition from summer to winter, the characteristics are mainly exhibited by the establishment of the easterly VIMT belt located in the tropical area, accompanied by some events occurring in "key periods". Further analyses disclose a great difference between the Indian and East Asian monsoon regions when viewed from the meridional migration of the westerly VIMT during the seasonal change process, according to which the Asian monsoon region can be easily divided into two parts along the western side of the Indochina Peninsula and it may also denote different formation mechanisms between the two regions. 展开更多
关键词 seasonal transition moisture transport Asian-Australian monsoon
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Collective transport of Lennard-Jones particles through one-dimensional periodic potentials
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作者 何健辉 温家乐 +2 位作者 陈沛荣 郑冬琴 钟伟荣 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第7期7-14,共8页
The surrounding media in which transport occurs contains various kinds of fields, such as particle potentials and external potentials. One of the important questions is how elements work and how position and momentum ... The surrounding media in which transport occurs contains various kinds of fields, such as particle potentials and external potentials. One of the important questions is how elements work and how position and momentum are redistributed in the diffusion under these conditions. For enriching Fick's law, ordinary non-equilibrium statistical physics can be used to understand the complex process. This study attempts to discuss particle transport in the one-dimensional channel under external potential fields. Two kinds of potentials—the potential well and barrier—which do not change the potential in total, are built during the diffusion process. There are quite distinct phenomena because of the different one-dimensional periodic potentials. By the combination of a Monte Carlo method and molecular dynamics, we meticulously explore why an external potential field impacts transport by the subsection and statistical method. Besides, one piece of evidence of the Maxwell velocity distribution is confirmed under the assumption of local equilibrium. The simple model is based on the key concept that relates the flux to sectional statistics of position and momentum and could be referenced in similar transport problems. 展开更多
关键词 transport external potential collective diffusion Maxwell velocity distribution
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Formation of Edge Transport Barriers by L-H Transition and Large Reversed Plasma Current on LHD
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作者 K. TOI S. OHDACHI +14 位作者 F. WATANABE K. NARIHARA T. MORISAKI 高翔 M. GOTO K. IDA S. MASUZAKI K. MIYAZAWA S. MOR.ITA S. SAKAKIBARA K. TANAKA T. TOKUZAWA K.W. WATANABE 严龙文 M. YOSHINUMA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第1期5-9,共5页
On the Large Helical Device (LHD) where nested magnetic surfaces are surrounded by the ergodic field layer, edge transport barrier (ETB) was produced in neutral-beam-injection (NBI) heated plasmas through transi... On the Large Helical Device (LHD) where nested magnetic surfaces are surrounded by the ergodic field layer, edge transport barrier (ETB) was produced in neutral-beam-injection (NBI) heated plasmas through transition and non-transition processes. The former case is the ETB formation by L-Htransition, where characteristics of L-H transition observed in a tokamak plasma are clearly recognized. The confinement improvement is the modest (- 10%), compared with the ISS95 international stellarator scaling. The threshold power for the transition is comparable or slightly lower than the ITER scaling law established by tokamaks and compact tori. The ETB is formed inside the ergodic field layer of the vacuum field. The ETB formation destabilizes edge coherent modes such as m/n = 1/1, 2/3 and 1/2, of which rational surfaces are in the magnetic hill. The formed ETB is partially and transiently destroyed by these coherent edge MHD modes and edge localized modes (ELMs) typically observed in Ha signals. The latter ETB is observed in a plasma with large reversed NBI-driven current more than 100 kA at Bt = 1 T. In these plasmas, the edge magnetic shear is enhanced by the current and the rotational transform in the core region is expected to be appreciably reduced. Thus reduced rotational transform in the plasma central region will enhance outward heat and particle fluxes toward ergodic edge layer. The ETB with steep electron temperature gradient up to - 5 keV/m is formed by blocking enhanced outward heat flux. 展开更多
关键词 edge transport barrier ergodic field layer L-H transition ELMS edge MHD modes
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Effects of Hyperosmolality on Expression of Urea Transporter A2 and Aquaporin 2 in Mouse Medullary Collecting Duct Cells
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作者 金文敏 姚曦 +4 位作者 王桃霞 冀倩倩 李永霞 杨晓 姚丽君 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2012年第1期59-64,共6页
In this study,the effects of hyperosmolality on the expression of urea transporter A2 (UTA2) and aquaporin 2 (AQP2) were investigated in transfected immortalized mouse medullary collecting duct (mIMCD3) cell line.AQP2... In this study,the effects of hyperosmolality on the expression of urea transporter A2 (UTA2) and aquaporin 2 (AQP2) were investigated in transfected immortalized mouse medullary collecting duct (mIMCD3) cell line.AQP2-GFP-pCMV6 and UTA2-GFP-pCMV6 plasmids were stably transfected into mIMCD3 cells respectively.Transfected mIMCD3 and control cells were cultured in different hy-pertonic media,which were made by NaCl alone,urea alone,or an equiosmolar mixture of NaCl and urea.The mRNA and protein expression of AQP2 was elevated by the stimulation of NaCl alone,urea alone and NaCl plus urea in AQP2-mIMCD3 cells;whereas NaCl alone and NaCl plus urea rather than urea alone increased the mRNA and protein expression of UTA2 in UTA2-mIMCD3 cells,and all the expression presented an osmolality-dependent manner.Moreover,the mRNA and protein expression of UTA2 rather than AQP2 was found to be synergistically up-regulated by a combination of NaCl and urea in mIMCD3 cells.It is concluded that NaCl and urea synergistically induce the expression of UTA2 rather than AQP2 in mIMCD3 cells,and hyperosmolality probably mediates the expression of AQP2 and UTA2 through different mechanisms. 展开更多
关键词 aquaporin 2 urea transporter A2 HYPEROSMOLALITY inner medullary collecting duct
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Phase transition and charge transport through a triple dot device beyond the Kondo regime
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作者 熊永臣 朱占武 贺泽东 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期628-634,共7页
Semiconductor quantum dot structure provides a promising basis for quantum information processing, within which to reveal the quantum phase and charge transport is one of the most important issues. In this paper, by m... Semiconductor quantum dot structure provides a promising basis for quantum information processing, within which to reveal the quantum phase and charge transport is one of the most important issues. In this paper, by means of the numerical renormalization group technique, we study the quantum phase transition and the charge transport for a parallel triple dot device in the strongly correlated limit, focusing on the effect of inter-dot hopping t beyond the Kondo regime. We find the quantum behaviors depend closely on the initial electron number on the dots, and the present model may map to single,double, and side-coupled impurity models in different parameter spaces. An orbital spin-1/2 Kondo effect between the conduction leads and the bonding orbital, and several magnetic-frustration phases are demonstrated when t is adjusted to different regimes. To understand these phenomena, a canonical transformation of the energy levels is given, and important physical quantities with respect to increasing t and necessary theoretical discussions are shown. 展开更多
关键词 semiconductor quantum dot device parallel triple dot structure quantum phase transition charge transport strongly correlated effect
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A new formula of recovery factor for non-equilibrium transport of graded suspended sediment in the Middle Yangtze River 被引量:1
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作者 LI Lin-lin XIA Jun-qiang +2 位作者 ZHOU Mei-rong DENG Shan-shan LI Zhi-wei 《Journal of Mountain Science》 SCIE CSCD 2023年第1期87-100,共14页
Suspended sediment concentrations in the Middle Yangtze River(MYR)reduced greatly after the Three Gorges Project operation,causing the composition of bed material to coarsen continuously.However,little is known about ... Suspended sediment concentrations in the Middle Yangtze River(MYR)reduced greatly after the Three Gorges Project operation,causing the composition of bed material to coarsen continuously.However,little is known about the non-equilibrium transport of graded suspended sediment owing to different bed material compositions(BMCs)along the MYR,and it is necessary to determine the magnitude of recovery factor.Using the Markov stochastic process in conjunction with the hiding-exposure effect of non-uniform bed-material,a new formula is proposed for calculating the recovery factor including the effect of different BMCs,and it is incorporated into the non-equilibrium transport equation to simulate the recovery processes of suspended load in both sand-gravel bed and sand bed reaches of the MYR.The results show that:(i)the recovery rate of graded sediment concentrations at Zhicheng was slower than that at Shashi during the period 2003-2007;(ii)the mean recovery factors of the coarse,medium,and fine sediment fractions in the ZhichengShashi reach were 0.152,0.0012,and 0.0005,respectively,and the coarse sediment recovered up to the maximum sediment concentration of 0.138 kg/m3over a distance of 15 km;and(iii)the results of the new formula that can consider the effect of bed material composition are in general agreement with the field observations,and the spatial and temporal delay effects are inversely related to particle size and BMC.Consequently,the BMC effect on the nonequilibrium sediment transport in different reaches of the MYR needs to be considered for higher simulation accuracy. 展开更多
关键词 non-equilibrium sediment transport bed material composition transition probability recovery factor Middle Yangtze River
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Effects of the HMT on Nucleon Collective Flows within BUU Transport Model
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作者 张芳 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第1期27-30,共4页
Within the framework of a semiclassical Boltzmann-Uehling-Uhlenbeck (BUU) transport model, the high mo- mentum tail (HMT) effects of nucleon momentum distribution in the nucleus on the nucleon collective flows are... Within the framework of a semiclassical Boltzmann-Uehling-Uhlenbeck (BUU) transport model, the high mo- mentum tail (HMT) effects of nucleon momentum distribution in the nucleus on the nucleon collective flows are studied in semieentral Au+Au collisions. The HMT due to the isospin-dependent short-range correlations causes a smaller value of the collective flows. We find that the HMT effects on the nucleon collective flows are remarkable at beam energy of 300 MeV/nucleon and become weak as the incident beam energy increases. The results indicate that for the collective flow studies at intermediate energies, the HMT of nucleon momentum distribution in nucleus should be taken into account in transport models. 展开更多
关键词 HMT IS of Effects of the HMT on Nucleon collective Flows within BUU transport Model in on
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A Multi-Mode Public Transportation System Using Vehicular to Network Architecture
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作者 Settawit Poochaya Peerapong Uthansakul +8 位作者 Monthippa Uthansakul Patikorn Anchuen Kontorn Thammakul Arfat Ahmad Khan Niwat Punanwarakorn Pech Sirivoratum Aranya Kaewkrad Panrawee Kanpan Apichart Wantamee 《Computers, Materials & Continua》 SCIE EI 2022年第12期5845-5862,共18页
The number of accidents in the campus of Suranaree University of Technology(SUT)has increased due to increasing number of personal vehicles.In this paper,we focus on the development of public transportation system usi... The number of accidents in the campus of Suranaree University of Technology(SUT)has increased due to increasing number of personal vehicles.In this paper,we focus on the development of public transportation system using Intelligent Transportation System(ITS)along with the limitation of personal vehicles using sharing economy model.The SUT Smart Transit is utilized as a major public transportation system,while MoreSai@SUT(electric motorcycle services)is a minor public transportation system in this work.They are called Multi-Mode Transportation system as a combination.Moreover,a Vehicle toNetwork(V2N)is used for developing theMulti-Mode Transportation system in the campus.Due to equipping vehicles with On Board Unit(OBU)and 4G LTE modules,the real time speed and locations are transmitted to the cloud.The data is then applied in the proposed mathematical model for the estimation of Estimated Time of Arrival(ETA).In terms of vehicle classifications and counts,we deployed CCTV cameras,and the recorded videos are analyzed by using You Only Look Once(YOLO)algorithm.The simulation and measurement results of SUT Smart Transit and MoreSai@SUT before the covid-19 pandemic are discussed.Contrary to the existing researches,the proposed system is implemented in the real environment.The final results unveil the attractiveness and satisfaction of users.Also,due to the proposed system,the CO_(2) gas gets reduced when Multi-Mode Transportation is implemented practically in the campus. 展开更多
关键词 Smart transit intelligent transportation system(ITS) dedicated short range communication(DSRC) vehicle to network(V2N) vehicle to everything(V2X) electric vehicle(EV) you only look once(YOLO)
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The Challenges Faced on Transit Transport Corridors by Landlocked Countries in Central Africa: Literature Review
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作者 Djasrabe Frederic Helai Huang Chenghui Mao 《Open Journal of Applied Sciences》 2021年第11期1200-1211,共12页
The landlocked countries are the one without access to the sea and can be assimilate as countries around the world with a disadvantage of geography situation location. Chad and the Central African Republic are two of ... The landlocked countries are the one without access to the sea and can be assimilate as countries around the world with a disadvantage of geography situation location. Chad and the Central African Republic are two of the 40 landlocked countries around the world that transport 80% of their goods by road and rail, and as much as almost more than 50% of their passengers through a transit country with a transit transport system which is crucial for their trade and exchanges. The study aims to introduce the importance to have a good and efficiency transport network infrastructure in Central Africa to facilitate the trade for the landlocked countries of Central Africa (Chad and the Central African Republic), member of CEMAC trade area and proposes some measures that can be adopt</span><span style="font-family:"">ed</span><span style="font-family:""> to improve their conditions and ameliorate the trade for those countries. 展开更多
关键词 Central Africa transit transport Corridor for Landlocked Countries
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LIM1863 is useful to explore collective cancer cell migration,and the group of heterogeneous cells undergoing collective migration behaves like a supracellular unit
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作者 JINSONG WU ZHENG ZHI +5 位作者 WENZHONG XU DIANCGENG LI QIUBO LI YAN HAN JIANMING HE XI LIANG 《BIOCELL》 SCIE 2023年第12期2671-2680,共10页
Collective cancer cell migration(CCCM)and epithelial-to-mesenchymal transition(EMT)play key roles in metastasis.This study reports that the colorectal carcinoma cell line LIM1863 is useful for the study of CCCM and EM... Collective cancer cell migration(CCCM)and epithelial-to-mesenchymal transition(EMT)play key roles in metastasis.This study reports that the colorectal carcinoma cell line LIM1863 is useful for the study of CCCM and EMT.Methods:Hematoxylin and eosin staining,scanning electron microscopy,transmission electron microscopy,and western blot analysis were performed.Results:LIM1863 automatically grew as spheroids in suspension and had important typical epithelial properties,including several layers of cells arranged around a central lumen,apical-basal polarity,and types of cell-cell junctions.Treatment with a combination of both TGF beta 1 and TNF alpha induced definite and distinct EMT,a spheroid changing phenotype to form a monolayer high-confluent patch without lumen,without polarity.Spontaneous CCCM occurred in spheroids.Flat EMT cells adhered to the base of a dish,exhibited persistent movement as a cluster of cells,and then shed,resulting in a cluster.All cells from one cluster undergoing CCCM died.Otherwise,all cells undergoing EMT disappeared and almost all cells located in the cell reservoir survived and proliferated.Conclusion:LIM1863 is an excellent cell line to study CCCM and EMT.The group of heterogeneous cells undergoing CCCM behaves like a supracellular unit. 展开更多
关键词 Colorectal cancer Epithelial-to-mesenchymal transition collective cell migration Supracellular migration METASTASIS
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公交专用车道规划管理思辨及公共汽电车交通发展纾困
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作者 孔令斌 徐康明 +16 位作者 陈小鸿 关宏志 安健 潘昭宇 高胜庆 杨涛 景国胜 周涛 邵丹 刘明姝 刘迁 苏跃江 钟志新 王园园 黄伟 郑猛 刘振国 《城市交通》 2024年第1期15-28,共14页
2023年上半年,公安部推出10项公安交管新措施,其中包括优化城市公交专用车道管理。北京、深圳、青岛、南通等地陆续发布公交专用车道相关管理措施,引发广泛讨论与关注。围绕公交专用车道管理措施背后的原因与调整的依据,公交专用车道本... 2023年上半年,公安部推出10项公安交管新措施,其中包括优化城市公交专用车道管理。北京、深圳、青岛、南通等地陆续发布公交专用车道相关管理措施,引发广泛讨论与关注。围绕公交专用车道管理措施背后的原因与调整的依据,公交专用车道本身的规划、管理与使用问题,以及公共汽电车交通运营困境,特邀城市交通行业专家学者和公共汽电车运营管理研究的一线工作人员以笔谈的形式交流观点。在此基础上,探索在城市存量发展阶段如何建立常态化路权变更规则和评估机制,以及公共汽电车交通纾困之路。 展开更多
关键词 交通治理 公共汽电车 公交专用车道 公交优先 路权 公平 效率 政策
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中国“新能源矿产目录”厘定研究
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作者 张艳飞 陈其慎 +7 位作者 邢佳韵 龙涛 郑国栋 任鑫 王琨 李媚 陈仁凤 张宇民 《中国矿业》 北大核心 2024年第1期1-11,共11页
全球能源体系正在加速从传统能源向新能源转变,新能源产业发展需要的矿产资源已成为大国博弈的焦点。科学厘定我国“新能源矿产目录”,对于保障国家能源安全和经济安全意义重大。首先,界定了新能源、新能源“产-储-运-用”体系、新能源... 全球能源体系正在加速从传统能源向新能源转变,新能源产业发展需要的矿产资源已成为大国博弈的焦点。科学厘定我国“新能源矿产目录”,对于保障国家能源安全和经济安全意义重大。首先,界定了新能源、新能源“产-储-运-用”体系、新能源矿产的概念,据此进一步提出了涵盖重要性、关键性及新能源领域对矿产需求影响程度3个维度的中国“新能源矿产目录”评价体系和评价方法;然后,按照“产-储-运-用”的4大环节梳理出新能源领域主要使用的43种矿产作为备选矿产清单,并通过系统评价确定了涵盖锂、铜、钒、硅(高纯石英)、钕、镝、镨、铽、铀、铂等19种矿产的中国“新能源矿产目录”;最后,分析了我国新能源矿产的供应保障情况,指出我国8种新能源矿产高度紧缺、依赖进口,另外11种矿产目前能够保障需求,未来极有可能面临供不应求、依赖进口的局面,亟需提前布局,加大勘查开发和投资力度,确保国家新能源矿产资源稳定供应。 展开更多
关键词 能源转型 新能源 新能源矿产 “产-储-运-用”体系 中国
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宅基地资格权回归集体成员权的实质与路径
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作者 杨青贵 《西南政法大学学报》 2024年第4期52-66,共15页
“三权分置”背景下的宅基地资格权,是“两权分置”背景下宅基地使用权中身份性内容析出后权利化的结果,但实质上源自集体所有权及其塑造的集体对成员“户有所居”保障关系。将宅基地资格权定位为集体成员权,符合宅基地资格权探索的实... “三权分置”背景下的宅基地资格权,是“两权分置”背景下宅基地使用权中身份性内容析出后权利化的结果,但实质上源自集体所有权及其塑造的集体对成员“户有所居”保障关系。将宅基地资格权定位为集体成员权,符合宅基地资格权探索的实践理性,是宅基地资格权向集体成员权的应然回归。宅基地资格权由集体成员组成的农户所拥有的宅基地分配请求权、宅基地使用权回复权、宅基地补助补偿权及衔接权能构成,其行使不得违背“限禁规则”。基于保障功能及其对应集体成员权实现的要求,宅基地资格权设定应当采取登记生效模式,并明确村级农村集体经济组织或村民委员会在宅基地管理中的权限,代表成员集体开展宅基地资格权认定与登记工作。将“自愿有偿”作为主体放弃宅基地资格权的强制要求,坚持宅基地资格权不得流转,并以“户有所居”保障功能实现为依据。通过相应的衔接规则,可以实现宅基地资格权与集体住房保障、国家住房保障、土地征收制度有序衔接。 展开更多
关键词 宅基地资格权 集体成员权 衔接规则 保障功能
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