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Discovery and inspiration of large-and medium-sized glutenite-rich oil and gas fields in the eastern South China Sea:An example from Paleogene Enping Formation in Huizhou 26 subsag,Pearl River Mouth Basin 被引量:1
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作者 XU Changgui GAO Yangdong +4 位作者 LIU Jun PENG Guangrong LIU Pei XIONG Wanlin SONG Penglin 《Petroleum Exploration and Development》 SCIE 2024年第1期15-30,共16页
Based on the practice of oil and gas exploration in the Huizhou Sag of the Pearl River Mouth Basin,the geochemical indexes of source rocks were measured,the reservoir development morphology was restored,the rocks and ... Based on the practice of oil and gas exploration in the Huizhou Sag of the Pearl River Mouth Basin,the geochemical indexes of source rocks were measured,the reservoir development morphology was restored,the rocks and minerals were characterized microscopically,the measured trap sealing indexes were compared,the biomarker compounds of crude oil were extracted,the genesis of condensate gas was identified,and the reservoir-forming conditions were examined.On this basis,the Paleogene Enping Formation in the Huizhou 26 subsag was systematically analyzed for the potential of oil and gas resources,the development characteristics of large-scale high-quality conglomerate reservoirs,the trapping effectiveness of faults,the hydrocarbon migration and accumulation model,and the formation conditions and exploration targets of large-and medium-sized glutenite-rich oil and gas fields.The research results were obtained in four aspects.First,the Paleogene Wenchang Formation in the Huizhou 26 subsag develops extensive and thick high-quality source rocks of semi-deep to deep lacustrine subfacies,which have typical hydrocarbon expulsion characteristics of"great oil generation in the early stage and huge gas expulsion in the late stage",providing a sufficient material basis for hydrocarbon accumulation in the Enping Formation.Second,under the joint control of the steep slope zone and transition zone of the fault within the sag,the large-scale near-source glutenite reservoirs are highly heterogeneous,with the development scale dominated hierarchically by three factors(favorable facies zone,particle component,and microfracture).The(subaqueous)distributary channels near the fault system,with equal grains,a low mud content(<5%),and a high content of feldspar composition,are conducive to the development of sweet spot reservoirs.Third,the strike-slip pressurization trap covered by stable lake flooding mudstone is a necessary condition for oil and gas preservation,and the NE and nearly EW faults obliquely to the principal stress have the best control on traps.Fourth,the spatiotemporal configuration of high-quality source rocks,fault transport/sealing,and glutenite reservoirs controls the degree of hydrocarbon enrichment.From top to bottom,three hydrocarbon accumulation units,i.e.low-fill zone,transition zone,and high-fill zone,are recognized.The main area of the channel in the nearly pressurized source-connecting fault zone is favorable for large-scale hydrocarbon enrichment.The research results suggest a new direction for the exploration of large-scale glutenite-rich reservoirs in the Enping Formation of the Pearl River Mouth Basin,and present a major breakthrough in oil and gas exploration. 展开更多
关键词 Pearl River Mouth Basin Huizhou Sag Huizhou 26 subsag PALEOGENE Enping Formation GLUTENITE large-and medium-sized oil and gas field
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Formation of large-and medium-sized Cretaceous volcanic reservoirs in the offshore Bohai Bay Basin,East China
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作者 XU Changgui ZHANG Gongcheng +3 位作者 HUANG Shengbing SHAN Xuanlong LIU Tingyu LI Jiahui 《Petroleum Exploration and Development》 SCIE 2024年第3期535-547,共13页
Based on the geological and geophysical data of Mesozoic oil-gas exploration in the sea area of Bohai Bay Basin and the discovered high-yield volcanic oil and gas wells since 2019,this paper methodically summarizes th... Based on the geological and geophysical data of Mesozoic oil-gas exploration in the sea area of Bohai Bay Basin and the discovered high-yield volcanic oil and gas wells since 2019,this paper methodically summarizes the formation conditions of large-and medium-sized Cretaceous volcanic oil and gas reservoirs in the Bohai Sea.Research shows that the Mesozoic large intermediate-felsic lava and intermediate-felsic composite volcanic edifices in the Bohai Sea are the material basis for the formation of large-scale volcanic reservoirs.The upper subfacies of effusive facies and cryptoexplosive breccia subfacies of volcanic conduit facies of volcanic vent-proximal facies belts are favorable for large-scale volcanic reservoir formation.Two types of efficient reservoirs,characterized by high porosity and medium to low permeability,as well as medium porosity and medium to low permeability,are the core of the formation of large-and medium-sized volcanic reservoirs.The reservoir with high porosity and medium to low permeability is formed by intermediate-felsic vesicular lava or the cryptoexplosive breccia superimposed by intensive dissolution.The reservoir with medium porosity and medium to low permeability is formed by intense tectonism superimposed by fluid dissolution.Weathering and tectonic transformation are main formation mechanisms for large and medium-sized volcanic reservoirs in the study area.The low-source“source-reservoir draping type”is the optimum source-reservoir configuration relationship for large-and medium-sized volcanic reservoirs.There exists favorable volcanic facies,efficient reservoirs and source-reservoir draping configuration relationship on the periphery of Bozhong Sag,and the large intermediate-felsic lava and intermediate-felsic composite volcanic edifices close to strike-slip faults and their branch faults are the main directions of future exploration. 展开更多
关键词 Bohai Sea CRETACEOUS large-and medium-sized volcanic reservoirs effective reservoir source-reservoir configuration exploration direction
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Small and Medium-Sized Enterprises Digital Management Facing Difficulties and Solutions
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作者 Jianhui Li 《Proceedings of Business and Economic Studies》 2024年第5期200-205,共6页
The advent of the digital era has provided strong technical support for the high-quality development of the social economy.The integration of the social economy with Internet technology has given rise to new industrie... The advent of the digital era has provided strong technical support for the high-quality development of the social economy.The integration of the social economy with Internet technology has given rise to new industries.However,the traditional development model of small and medium-sized enterprises(SMEs)is increasingly unable to meet the demands of economic growth,and digital management has gradually become a key approach for these enterprises to achieve their development goals.Currently,SMEs face challenges such as talent shortages,insufficient funds,and a lack of awareness regarding transformation.This paper will analyze the difficulties SMEs encounter in implementing digital management and explore potential development paths for their digital transformation. 展开更多
关键词 Small and medium-sized enterprises Digital management Market economy
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Research on the Coordinated Development of Inclusive Finance and Financing for Small and Medium-sized Enterprises
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作者 Yanfei Li Xue Liang 《Proceedings of Business and Economic Studies》 2024年第4期214-219,共6页
As an important force in promoting economic and social development,small and medium-sized enterprises play a crucial role in enhancing China’s economic strength,creating employment opportunities,and promoting industr... As an important force in promoting economic and social development,small and medium-sized enterprises play a crucial role in enhancing China’s economic strength,creating employment opportunities,and promoting industrial structural transformation.However,due to their inherent weaknesses,small and medium-sized enterprises often face difficulties in financing within the traditional financial service system.This makes it difficult for small and medium-sized enterprises to inject vitality into the development of the market economy by expanding their financing scale.Since 2013,China has vigorously developed inclusive finance and extended the services of traditional financial institutions to small and medium-sized enterprises,providing policy guidance,resource support,and technical support to alleviate the financing difficulties of small and medium-sized enterprises.Based on this,this article focuses on the current financing problems faced by small and medium-sized enterprises and specifically elaborates on how to lower the financing threshold for small and medium-sized enterprises and broaden their financing channels through inclusive finance,in order to promote the development of inclusive finance and a virtuous cycle of financing for small and medium-sized enterprises. 展开更多
关键词 Inclusive finance Financing for small and medium-sized enterprises Financial institution
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Research on the Generation of Professional Skill Modules for Talent Cultivation in the Landscape Architecture Profession for Industry-Education Integration of Small and Medium-Sized Enterprises
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作者 Fengyi Xu Yang Su 《Journal of Contemporary Educational Research》 2024年第6期227-232,共6页
Due to industry characteristics or regional limitations,many students in certain majors tend to seek employment in small and medium-sized enterprises(SMEs).SMEs face certain challenges in implementing industry-educati... Due to industry characteristics or regional limitations,many students in certain majors tend to seek employment in small and medium-sized enterprises(SMEs).SMEs face certain challenges in implementing industry-education integration,and there is a lack of mature methods in specific implementation processes and talent cultivation plan generation.Taking the landscape architecture profession as an example,this paper conducts a correlation analysis and cross-analysis of the industry-required professional skills based on surveys of over 300 industry practitioners employed in SMEs.It provides professional skill cultivation modules based on market feedback.This research process and analysis method have certain reference significance for the rapid production of adaptive talent cultivation professional skill modules in other industries targeting SMEs. 展开更多
关键词 Landscape architecture profession Talent cultivation Industry-education integration Small and medium-sized enterprises
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Maintenance,Repair,and Reinforcement Measures for Dilapidated Small and Medium-Sized Bridges
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作者 Xu Meng Bo Liu +1 位作者 Ji Li Zhi Tu 《Journal of Architectural Research and Development》 2024年第1期62-67,共6页
The paper initiates by exploring the importance of maintaining,repairing,and reinforcing bridges.Subsequently,it delves into routine and preventative maintenance measures tailored for small to medium-sized bridges.Add... The paper initiates by exploring the importance of maintaining,repairing,and reinforcing bridges.Subsequently,it delves into routine and preventative maintenance measures tailored for small to medium-sized bridges.Additionally,the paper examines repair and reinforcement techniques specifically designed for deteriorated small and medium-sized bridges,encompassing methods for fortifying both the bridge foundation and upper and lower structures.Lastly,the paper proposes suggestions aimed at fostering discussions and exchanges on the development of maintenance and repair processes for deteriorated small and medium-sized bridges. 展开更多
关键词 Dilapidated small and medium-sized bridges Maintenance Repair and reinforcement
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The Application of Knowledge Management(KM)by Small and Medium-Sized Enterprises(SME)in Manufacturing Industry
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作者 Danrui Yin Chin Lye Ooi 《Proceedings of Business and Economic Studies》 2024年第4期293-299,共7页
To accelerate the digital transformation of small and medium-sized manufacturing enterprises(SMEs),this study delves into the primary challenges encountered in adopting knowledge management(KM)within these organizatio... To accelerate the digital transformation of small and medium-sized manufacturing enterprises(SMEs),this study delves into the primary challenges encountered in adopting knowledge management(KM)within these organizations and identifies the essential methods for successful implementation.The objective is to provide practical recommendations for the effective adoption of KM.This research suggests that enterprises should promote knowledge management through three key approaches:enhancing employees’cognitive understanding,standardizing knowledge systems,and tailoring business scenarios to meet diverse needs.These findings offer valuable insights into the digital transformation of SMEs in the manufacturing sector,ultimately helping these businesses to remain competitive and innovative in a rapidly changing market.By addressing the specific needs and challenges faced by SMEs,this study aims to contribute to a more comprehensive understanding of how knowledge management can be leveraged to drive digital transformation and improve overall business performance. 展开更多
关键词 Knowledge management(KM) Small and medium-sized enterprises(SME) Manufacturing industry
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Comparative Test on Spring Medium-sized Watermelon Varieties in Beijing
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作者 Shengqi MU Chao MA +4 位作者 Jianbo ZENG Yanli CHEN Ying ZHANG Xuesong YOU Jin XU 《Agricultural Biotechnology》 CAS 2023年第3期20-22,共3页
[Objectives]This study was conducted to select suitable medium-sized watermelon varieties for early spring cultivation in Beijing.[Methods]Seven watermelon varieties were collected,including Beinong Tianjiao 2,Beinong... [Objectives]This study was conducted to select suitable medium-sized watermelon varieties for early spring cultivation in Beijing.[Methods]Seven watermelon varieties were collected,including Beinong Tianjiao 2,Beinong Tianjiao,Hongfuji,Yongfeng 1,Beinong Futian,Beinong Shijia,and Beinong Jinxiu,and Jingxin 2 was used as the control check(CK).The growth period,morphological traits,yield traits and fruit quality of the tested varieties were investigated.[Results]Beinong Tianjiao 2 had an earlier maturation stage,a fruit development period of 38 d and a total growth period of 118 d.It showed stable growth,with a single fruit weight of 7.56 kg,a fruit setting rate of 0.99 per plant,and a yield of 83076.9 kg/hm~2,which ranked,respectively,second,first,and second among all tested varieties,and were significantly superior to the CK.Furthermore,this variety had thin and tough peel,a bright red flesh color,high central sugar content,loose and crisp flesh,and a good taste.[Conclusions]It is preliminarily believed that it is suitable for early spring watermelon production in Beijing area. 展开更多
关键词 medium-sized watermelon Variety comparison Beijing area High yield High quality
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Application of Connected Truck Data to Evaluate Spatiotemporal Impact of Rest Area Closures on Ramp Parking
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作者 Jijo K. Mathew Jairaj Desai +1 位作者 Edward D. Cox Darcy M. Bullock 《Journal of Transportation Technologies》 2024年第3期289-307,共19页
Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck s... Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck stops are the only places for the trucks to stop legally and safely. In locations without sufficient parking areas, trucks often park on interstate ramps, which create safety risks for other interstate motorists. Historically, agencies have employed costly and time intensive manual counting methods, camera surveillance, and driver surveys to assess truck parking. Connected truck data, available in near real-time, offers an efficient alternative to practitioners to assess truck parking patterns and identify areas where there may be insufficient safe parking spaces. This paper presents a case study of interstate I-70 in east central Indiana and documents the observed spatiotemporal impacts of a rest area closure on truck parking on nearby interstate ramps. Results showed that there was a 28% increase in parking on ramps during the rest area closure. Analysis also found that ramps closest to the rest area were most impacted by the closure, seeing a rise in truck parking sessions as high as 2.7 times. Parking duration on the ramps during rest area closure also increased drastically. Although it was expected that this would result in increased parking by trucks on adjacent ramps, this before, during, after scenario provided an ideal scenario to evaluate the robustness of these techniques to assess changing parking characteristics of long-haul commercial trucks. The data analytics and visualization tools presented in this study are scalable nationwide and will aid stakeholders in informed data-driven decision making when allocating resources towards improving the nations commercial vehicle parking infrastructure. 展开更多
关键词 Connected truck Data Rest Areas Exit Ramps truck Parking Commercial Vehicles
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Excessive Drowsiness among Truck Drivers in Benin in 2023: Associated Factors and Risk of Crashes Occurrence
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作者 Mongbo Virginie Mobali Wilondja Célestin Kpozehouen Alphonse 《Open Journal of Epidemiology》 2024年第1期167-179,共13页
Introduction: Over-drowsiness is a condition with serious consequences, including road accidents. The condition, however, is often ignored both by carers as well as victims themselves. The aim of the present study was... Introduction: Over-drowsiness is a condition with serious consequences, including road accidents. The condition, however, is often ignored both by carers as well as victims themselves. The aim of the present study was to investigate the factors associated with excessive drowsiness in Cotonou, Benin 2023, along with its influence on the occurrence of crashes among truck drivers. Methods: This was a descriptive and analytical cross-sectional study, held from March 13 to April 10, 2023, focusing on large truck drivers over 18 years of age, selected by convenience from parking lots in and around the city of Cotonou. Data collected using questionnaires on socio-demographic and behavioral factors, sleeping habits and working conditions were processed using Stata 15.0 software. Excessive drowsiness was defined by a score above 10 on the Epworth scale. Associated factors were found by multiple logistic regression, at a threshold of 0.05. Results: Altogether 304 drivers, all male and aged 35.98 ± 8.42 years, were surveyed. The prevalence of excessive drowsiness was 29.2%. The associated factors identified were not practicing sport OR = 2.27, CI95% = [1.33;3.86], p = 0,002;sleep duration per working day OR = 1.82;CI95% = [1.06;3.11], p = 0,027 and average distance travelled per day OR = 3.40;CI95% = [1.53;7.56], p = 0,003. Excessive drowsiness was associated with a 1.73-fold increased risk of road accidents (CI95% [1.04;2.87];p = 0.03). Conclusion: Communicating excessive drowsiness and its associated factors to all the stakeholders in the haulage chain is essential to help prevent road accidents. 展开更多
关键词 DROWSINESS Large trucks Accidents BENIN
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A comparative study on kinetics and dynamics of two dump truck lifting mechanisms using MATLAB simscape
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作者 Thong Duc Hong Minh Quang Pham +2 位作者 Son Cong Tran Lam Quang Tran Truong Thanh Nguyen 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第2期146-156,共11页
In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been developed.The mechanical and hydraulic simulation models are e... In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been developed.The mechanical and hydraulic simulation models are established using MATLAB Simscape to analyze their kinetics and dynamics in the lifting and holding stages.The simulation findings are compared to the analytical calculation results in the steady state,and both methods show good agreement.In the early lifting stage,Model 1 produces greater force and discharges goods in the container faster than Model 2.Meanwhile,Model 2 reaches a higher force and ejects goods from the container cleaner than its counterpart at the end lifting stage.The established simulation models can consider the effects of dynamic loads due to inertial moments and forces generated during the system operation.It is crucial in studying,designing,and optimizing the structure of hydraulic-mechanical systems. 展开更多
关键词 Dump truck Lifting mechanism HYDRAULIC MATLAB Simscape Kinetic dynamic analysis
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Intermodal Competition: Cargo Airships versus Long-Haul Trucking for Perishable Commodities
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作者 Barry Everett Prentice 《Journal of Transportation Technologies》 2024年第2期195-211,共17页
Intermodal competition changes with changes in technology, economics, and environmental concerns. Trucks and airships are generally considered not to be competitors, but this depends on the distance of haul. The tonne... Intermodal competition changes with changes in technology, economics, and environmental concerns. Trucks and airships are generally considered not to be competitors, but this depends on the distance of haul. The tonne-kilometer cost of trucking rises much more quickly with distance than it does the cost of a cargo airship. At some distance, the two modes are direct substitutes. The costs of the Mexico-Canada refrigerated truck supply chain are compared with the costs of a 100t-lift, electrically-powered airship. The flight characteristics of the Hindenburg Zeppelin are used as a model for a modern cargo airship. The supply chain cost of trucking tomatoes is used to test the theorical proposition. The cost difference works out to about US10¢/kg (5¢/lb) advantage for trucking Mexican tomatoes to Canada. However, this cost disadvantage of the airship could be made up by their vibrationless ride, better air circulation and one-day service versus four days by truck. This alternative form of transportation could have a positive impact on worldwide north-south distribution of food. Airships can overcome trade barriers and distance to open new markets for perishable food exports. In addition, they would reduce the carbon emissions of transport. Canada imports 160,000 refrigerated truckloads of fruits and vegetables by from the southern US and Mexico. With an average driving distance of 3,000 km, these trucks emit 606,000 MT of CO<sub>2</sub> annually. Airships powered by hydrogen fuel cells would have zero-carbon emissions. Markets are not yet incorporating the environmental advantage of airships in any freight comparison, but inevitably this will be important. 展开更多
关键词 AIRSHIP Refrigerated trucks Mexico Tomatoes Carbon-emissions Perishables
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Quantifying the Impact of In-Cab Alerts on Truck Speed Reductions in Ohio
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作者 Jairaj Desai Jijo K. Mathew Darcy M. Bullock 《Journal of Transportation Technologies》 2024年第3期273-288,共16页
In-cab alerts warn commercial vehicle drivers of upcoming roadway incidents, slowdowns and work zone construction activities. This paper reports on a study evaluating the driver response to in-cab alerts in Ohio. Driv... In-cab alerts warn commercial vehicle drivers of upcoming roadway incidents, slowdowns and work zone construction activities. This paper reports on a study evaluating the driver response to in-cab alerts in Ohio. Driver response was evaluated by measuring the statistical trends of vehicle speeds after the in-cab alerts were received. Vehicle speeds pre and post in-cab alert were collected over a 47 day period in the fall of 2023 for trucks traveling on interstate roadways in Ohio. Results show that approximately 22% of drivers receiving Dangerous Slowdown alerts had reduced their speeds by at least 5 mph 30 seconds after receiving such an alert. Segmenting this analysis by speed found that of vehicles traveling at or above 70 mph at the time of alerting, 26% reduced speeds by at least 5 mph. These speed reductions suggest drivers taking actional measures after receiving alerts. Future studies will involve further analysis on the impact of the types of alerts shown, roadway characteristics and overall traffic conditions on truck speeds passing through work zones. 展开更多
关键词 In-Cab Alerts Connected truck Data Driver Alerts Dangerous Slowdowns
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Seroprevalence Survey of HIV and Hepatitis B Virus and Behavioral Characteristics among Heavy Truck Drivers along Port Sudan-Khartoum Highways
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作者 Sara S. Osman Adam A. Mattar Omnia M. Hamid 《Open Journal of Medical Microbiology》 2024年第1期11-22,共12页
The prevalence of human immunodeficiency virus (AIDS) and hepatitis B virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The pr... The prevalence of human immunodeficiency virus (AIDS) and hepatitis B virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The present study aimed to screen for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and behavioral characteristics among heavy truck drivers in Port Sudan. A cross-sectional study was conducted on 274 heavy truck drivers and their assistants who used the highway Port Sudan-Khartoum in Port Sudan city during 2019-2021. Data on behavioral characteristics and substance use habits were collected using a structured questionnaire, and an ELISA test was used to screen for HIV and HBV infections in the study participants. The chi-square test, odds ratio, and confidence intervals were used to find the association between behavioral characteristics and seropositive HIV/HBV. Of the 274 enrolled participants, the seroprevalence rates of HIV were 2.7% and HBV was 23.7%. Ninety-four (34.3%) of them had a history of high-risk sexual behavior outside of marriage;only two (0.7%) used condoms;14.2% of participants reported alcohol use;and 1.1% reported drug use. Univariate analysis revealed that having a sex history outside of marriage with ≥1 sex partner and never using a condom with a spouse or casual partner were significant risk factors for HIV and HBV among drivers. Fortunately, we found that most of the drivers reported low alcohol and drug use. Concerning this study, the seroprevalence of HIV and HBV is highly associated with a history of having sex outside of marriage and sexual behavior among truck drivers and assistances. Additional studies are needed to further investigate other STIs and behavioral characteristics associated with factors in truck drivers/assistance in different truck stop regions in Sudan. 展开更多
关键词 Sexual Transmitted Infection Port Sudan truck Drivers/Assistance
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Real-Time Co-optimization of Gear Shifting and Engine Torque for Predictive Cruise Control of Heavy-Duty Trucks
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作者 Hongqing Chu Xiaoxiang Na +4 位作者 Huan Liu Yuhai Wang Zhuo Yang Lin Zhang Hong Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期294-317,共24页
Fuel consumption is one of the main concerns for heavy-duty trucks.Predictive cruise control(PCC)provides an intriguing opportunity to reduce fuel consumption by using the upcoming road information.In this study,a rea... Fuel consumption is one of the main concerns for heavy-duty trucks.Predictive cruise control(PCC)provides an intriguing opportunity to reduce fuel consumption by using the upcoming road information.In this study,a real-time implementable PCC,which simultaneously optimizes engine torque and gear shifting,is proposed for heavy-duty trucks.To minimize fuel consumption,the problem of the PCC is formulated as a nonlinear model predictive control(MPC),in which the upcoming road elevation information is used.Finding the solution of the nonlinear MPC is time consuming;thus,a real-time implementable solver is developed based on Pontryagin’s maximum principle and indirect shooting method.Dynamic programming(DP)algorithm,as a global optimization algorithm,is used as a performance benchmark for the proposed solver.Simulation,hardware-in-the-loop and real-truck experiments are conducted to verify the performance of the proposed controller.The results demonstrate that the MPC-based solution performs nearly as well as the DP-based solution,with less than 1%deviation for testing roads.Moreover,the proposed co-optimization controller is implementable in a real-truck,and the proposed MPC-based PCC algorithm achieves a fuel-saving rate of 7.9%without compromising the truck’s travel time. 展开更多
关键词 Heavy-duty truck Predictive cruise control Model predictive control Pontryagin’s maximum principle Real-truck implementation
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A human-sensitive frequency band vibration isolator for heavy-duty truck seats
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作者 Qingqing LIU Shenlong WANG +5 位作者 Ge YAN Hu DING Haihua WANG Qiang SHI Xiaohong DING Huijie YU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第10期1733-1748,共16页
In this study,a human-sensitive frequency band vibration isolator(HFBVI)with quasi-zero stiffness(QZS)characteristics for heavy-duty truck seats is designed to improve the comfort of heavy-duty truck drivers on uneven... In this study,a human-sensitive frequency band vibration isolator(HFBVI)with quasi-zero stiffness(QZS)characteristics for heavy-duty truck seats is designed to improve the comfort of heavy-duty truck drivers on uneven roads.First,the analytical expressions for the force and displacement of the HFBVI are derived with the Lagrange equation and d'Alembert's principle,and are validated through the prototype restoring force testing.Second,the harmonic balance method(HBM)is used to obtain the dynamic responses under harmonic excitation,and further the influence of pre-stretching on the dynamic characteristics and transmissibility is discussed.Finally,the experimental prototype of the HFBVI is fabricated,and vibration experiments are conducted under harmonic excitation to verify the vibration isolation performance(VIP)of the proposed vibration isolator.The experimental results indicate that the HFBVI can effectively suppress the frequency band(4-8 Hz)to which the human body is sensitive to vertical vibration.In addition,under real random road spectrum excitation,the HFBVI can achieve low-frequency vibration isolation close to 2 Hz,providing new prospects for ensuring the health of heavy-duty truck drivers. 展开更多
关键词 human-sensitive frequency band quasi-zero stiffness(QZS) heavy-duty truck seat real random road spectrum low-frequency vibration isolation
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A Predictive Energy Management Strategies for Mining Dump Trucks
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作者 Yixuan Yu Yulin Wang +1 位作者 Qingcheng Li Bowen Jiao 《Energy Engineering》 EI 2024年第3期769-788,共20页
The plug-in hybrid vehicles(PHEV)technology can effectively address the issues of poor dynamics and higher energy consumption commonly found in traditional mining dump trucks.Meanwhile,plug-in hybrid electric trucks c... The plug-in hybrid vehicles(PHEV)technology can effectively address the issues of poor dynamics and higher energy consumption commonly found in traditional mining dump trucks.Meanwhile,plug-in hybrid electric trucks can achieve excellent fuel economy through efficient energy management strategies(EMS).Therefore,a series hybrid system is constructed based on a 100-ton mining dump truck in this paper.And inspired by the dynamic programming(DP)algorithm,a predictive equivalent consumption minimization strategy(P-ECMS)based on the DP optimization result is proposed.Based on the optimal control manifold and the SOC reference trajectory obtained by the DP algorithm,the P-ECMS strategy performs real-time stage parameter optimization to obtain the optimal equivalent factor(EF).Finally,applying the equivalent consumption minimization strategy(ECMS)realizes real-time control.The simulation results show that the equivalent fuel consumption of the P-ECMS strategy under the experimentally collected mining cycle conditions is 150.8 L/100 km,which is 10.9%less than that of the common CDCS strategy(169.3 L/100 km),and achieves 99.47%of the fuel saving effect of the DP strategy(150 L/100 km). 展开更多
关键词 Mining dump truck energy management strategy plug-in hybrid electric vehicle equivalent consumption minimization strategy dynamic programming
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Reducing Electrical Consumption in Stationary Long-Haul Trucks
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作者 Kajal Sheth Dhvanil Patel Gautam Swami 《Open Journal of Energy Efficiency》 2024年第3期88-99,共12页
On average, long-haul trucks in the U.S. use approximately 667 million gallons of fuel each year just for idling. This idling primarily facilitates climate control operations during driver rest periods. To mitigate th... On average, long-haul trucks in the U.S. use approximately 667 million gallons of fuel each year just for idling. This idling primarily facilitates climate control operations during driver rest periods. To mitigate this, our study explored ways to diminish the electrical consumption of climate control systems in class 8 trucks through innovative load reduction technologies. We utilized the CoolCalc software, developed by the National Renewable Energy Laboratory (NREL), which integrates heat transfer principles with extensive weather data from across the U.S. to mimic the environmental conditions trucks face year-round. The analysis of the CoolCalc simulations was performed using MATLAB. We assessed the impact of various technologies, including white paint, advanced curtains, and Thinsulate insulation on reducing electrical demand compared to standard conditions. Our findings indicate that trucks operating in the eastern U.S. could see electrical load reductions of up to 40%, while those in the western regions could achieve reductions as high as 55%. Such significant decreases in energy consumption mean that a 10 kWh battery system could sufficiently manage the HVAC needs of these trucks throughout the year without idling. Given that many long-haul trucks are equipped with battery systems of around 800 Ah (9.6 kWh), implementing these advanced technologies could substantially curtail the necessity for idling to power air conditioning systems. 展开更多
关键词 Long-Haul trucks Electricity Consumption Idling Reduction HVAC Systems Climate Control Energy Efficiency
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基于TruckSim矿用汽车转向工况侧倾运动特性分析 被引量:2
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作者 王旭斌 徐珂 《机械设计与制造》 北大核心 2023年第6期193-196,共4页
车辆发生转向时,由于离心力的作用而产生侧倾运动,空载高速转向时该部分作用将更为明显,进而影响车辆平稳运输。根据悬挂系统的特性差异,对所研究矿用汽车前后悬挂的侧倾中心和侧倾轴进行分析;基于以上分析,对转向时的侧倾运动进行分析... 车辆发生转向时,由于离心力的作用而产生侧倾运动,空载高速转向时该部分作用将更为明显,进而影响车辆平稳运输。根据悬挂系统的特性差异,对所研究矿用汽车前后悬挂的侧倾中心和侧倾轴进行分析;基于以上分析,对转向时的侧倾运动进行分析,获取关键参数的变化模型;根据理论分析结果,基于Matlab/Simulink建立车辆转向工况表征侧倾运动的分析模型;根据悬挂特性和转向特性,分别建立分析模型,与车辆多体动力学模型联合,基于TruckSim建立整车转向特征分析模型;分析在固定转向盘稳态回转试验时,车辆的行驶轨迹;对空载高速转向工况下,车辆内外轮转角特征曲线,悬挂刚度、位移、侧倾刚度等参数变化进行分析;对比分析考虑转向侧倾与否的转角特征及偏差与理论分析之间的差异,以验证分析的可靠性。结果可知:车辆内外侧悬挂缸出现伸缩跳动,此时出现了附加转向效应叠加在车轮上;车轮需要较大的侧偏角,满足侧向力的需要;此时,整车的转向角关系不单单满足Ackerman定理,还增加了轮胎的侧偏角;未考虑转向侧倾时,转角偏差值随着转角的增加而不断增大,最大偏差达到了0.4223°,而考虑时,转角偏差的目标值为0.3618°。因此表明,所建立的分析模型具有较好的分析结果,能够更精确的反应车辆转向过程中,侧倾运动各部分参数的变化,为此类研究提供参考。 展开更多
关键词 矿用汽车 油气悬挂 刚度 侧倾运动 转向工况 模型
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Clinical outcome of medium-sized hepatocellular carcinoma treated with microwave ablation 被引量:10
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作者 Ai-Xue Sun Zhi-Li Cheng +5 位作者 Pan-Pan Wu Yue-Hong Sheng Xiu-Juan Qu Wen Lu Cheng-Gong Zhao Guo-Jun Qian 《World Journal of Gastroenterology》 SCIE CAS 2015年第10期2997-3004,共8页
AIM:To evaluate the outcomes of patients withmedium-sized hepatocellular carcinoma(HCC)who underwent percutaneous microwave ablation(MWA).METHODS:We retrospectively reviewed all patients with a single medium-sized HCC... AIM:To evaluate the outcomes of patients withmedium-sized hepatocellular carcinoma(HCC)who underwent percutaneous microwave ablation(MWA).METHODS:We retrospectively reviewed all patients with a single medium-sized HCC who underwent percutaneous MWA from January 2010 to January2013.Technical success,technical effectiveness and complications were subsequently observed.Survival curves were constructed using the Kaplan-Meier method.The Cox proportional hazards model was fitted to each variable.The relative prognostic significance o f t h e va r i a b l e s fo r p re d i c t i n g ove ra l l s u r v i va l rate,recurrence-free survival rate and local tumor recurrence(s)was assessed using univariate analysis.All variables with a P value<0.20 were subjected to multivariate analysis.RESULTS:The study included 182 patients(mean age,58 years;age range:22-86 years)with a single HCC(mean size,3.72±0.54 cm;range:3.02-5.00cm).The estimated technical effectiveness rate was93%in 182 patients.The major complication rate was2.7%(5/182),including liver abscess in 4 cases,and abdominal bleeding at the puncture site in 1 case.Thirty-day mortality rate was 0.5%(1/182).One patient died due to liver abscess-related septicemia.Cumulative recurrence-free survival and overall survival(OS)rates were 51%,36%,27%and 89%,74%,60%at 1,2,and 3 years,respectively.Age(P=0.017)and tumor diameter(P=0.029)were independent factors associated with local tumor recurrence.None of the factors had a statistically significant impact on recurrence-free survival.Serum albumin level(P=0.009)and new lesion(s)(P=0.029)were independently associated with OS.CONCLUSION:Percutaneous MWA is a relatively safe and effective treatment for patients with medium-sized HCC. 展开更多
关键词 HEPATOCELLULAR CARCINOMA medium-sized TUMOR Microw
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