According to China Daily on May 1, ZTE Corp plans to strengthen its position in the European market in the fields of telecom infrastructure, smart phones and government and enterprise solutions, according to company o...According to China Daily on May 1, ZTE Corp plans to strengthen its position in the European market in the fields of telecom infrastructure, smart phones and government and enterprise solutions, according to company officials.展开更多
Fossil fuels may be out of fashion,but sales of foreignowned resources across Asia are expected to attract a broad mix of bidders.Some of Asia’s biggest foreignowned oil and gas assets,worth more than US$40 billion,a...Fossil fuels may be out of fashion,but sales of foreignowned resources across Asia are expected to attract a broad mix of bidders.Some of Asia’s biggest foreignowned oil and gas assets,worth more than US$40 billion,are to be sold in 2017,with potential bidders expected to include Chinese energy companies and sovereign funds.Assets to be sold include US-based Chevron’s US$1billion(0.94 billion euros)joint ownership stake with China’s state-owned CNOOC in an offshore oil field.展开更多
Lhasa has witnessed many changes a is joined the whole of China embarking on the road towards a mar-ket economy,an abrupt switch from formnerly pre-vailing planned economy.
China has gained rich experience in the photovoltaic industry, and is capable of providing high-quality photovoltaic products and services at lower prices,
Recently,Internet of Drones(IoD)has garnered significant attention due to its widespread applications.However,deploying IoD for area coverage poses numerous limitations and challenges.These include interference betwee...Recently,Internet of Drones(IoD)has garnered significant attention due to its widespread applications.However,deploying IoD for area coverage poses numerous limitations and challenges.These include interference between neighboring drones,the need for directional antennas,and altitude restrictions for drones.These challenges necessitate the development of efficient solutions.This research paper presents a cooperative decision-making approach for an efficient IoDdeployment to address these challenges effectively.The primary objective of this study is to achieve an efficient IoDdeployment strategy thatmaximizes the coverage regionwhile minimizing interference between neighboring drones.In deployment problem,the interference increases as the number of deployed drones increases,resulting in bad quality of communication.On the other hand,deploying a few drones cannot satisfy the coverage demand.To accomplish this,an enhanced version of a concise population-based meta-heuristic algorithm,namely Improved Particle SwarmOptimization(IPSO),is applied.The objective function of IPSO is defined based on the coverage probability,which is primarily influenced by the characteristics of the antennas and drone altitude.A radio frequency(RF)model is derived to evaluate the coverage quality,considering both Line of Sight(LOS)and Non-Line of Sight(NLOS)down-link coverage probabilities for ground communication.It is assumed that each drone is equipped with a directional antenna to optimize coverage in a given region.Extensive simulations are conducted to assess the effectiveness of the proposed approach.Results demonstrate that the proposed method achieves maximum coverage with minimum transmission power.Furthermore,a comparison is made against Collaborative Visual Area Coverage Approach(CVACA),and a game-based approach in terms of coverage quality and convergence speed.The simulation results reveal that our approach outperforms both CVACA and the gamebased schemes in terms of coverage and convergence speed.Comparisons validate the superiority of our approach over existing methods.To assess the robustness of the proposed RFmodel,we have considered two distinct ranges of noise:range1 spanning from−120 to−90 dBm,and range2 spanning from−90 to−70 dBmfor different numbers of UAVs.In summary,this research presents a cooperative decision-making approach for efficient IoD deployment to address the challenges associatedwith area coverage and achieves an optimal coveragewithminimal interference.展开更多
AASHTO’s guideline for geometric design of highways and similar guidelines require that roadside areas on the inside of horizontal curves be cleared of high objects to provide stopping sight distance. The guidelines ...AASHTO’s guideline for geometric design of highways and similar guidelines require that roadside areas on the inside of horizontal curves be cleared of high objects to provide stopping sight distance. The guidelines have analytical models for determining the extent of clearance, known as the horizontal sightline offset or clearance offset, for simple curves. Researchers in the past have developed analytical models for clearance offsets for spiraled and reverse curves. Very few researchers developed analytical models for available sight distances for compound curves. Still missing are models for horizontal sightline offsets and locations of the offsets for compound curves. The objective of this paper is to present development of analytical models and charts for determining horizontal sightline offsets and their locations for compound curves. The paper considers curves whose component arcs are individually shorter than stopping sight distance. The resulting models and the charts have been verified with accurate values determined using graphical methods. The models and the charts will find application in geometric design of highway compound curves.展开更多
Having cleared all the hurdles to enter the market, locally incorporated foreign banks declare their intentions to dive into the personal housing loan business in China A battle is brewing between domestic and locally...Having cleared all the hurdles to enter the market, locally incorporated foreign banks declare their intentions to dive into the personal housing loan business in China A battle is brewing between domestic and locally incorporated foreign banks over展开更多
Following a strong start at the Spring Edition of Intertextile Shanghai Home Textiles early this year,global industry players have turned their sights to the next international event in August 2023.As the first Autumn...Following a strong start at the Spring Edition of Intertextile Shanghai Home Textiles early this year,global industry players have turned their sights to the next international event in August 2023.As the first Autumn Edition to be held in the wake of China lifting many of its pandemicrelated border restrictions,the three-day fair will gather around 1,000 international and domestic exhibitors.展开更多
针对非线性船舶航向控制系统,将Line of Sight(LOS)引导律与滑模控制算法相结合,设计一种航向保持滑模控制算法,通过设计合理的李雅普诺夫函数及利用其稳定性理论对系统的稳定性进行了分析,并利用"育龙"轮运动数学模型进行计...针对非线性船舶航向控制系统,将Line of Sight(LOS)引导律与滑模控制算法相结合,设计一种航向保持滑模控制算法,通过设计合理的李雅普诺夫函数及利用其稳定性理论对系统的稳定性进行了分析,并利用"育龙"轮运动数学模型进行计算机模拟仿真,验证设计思想的可行性和控制算法的合理性及有效性。仿真结果表明,控制算法可以保证航向控制系统的渐近收敛及稳定,根据该控制算法所设计的控制器,能够使船舶航向精确的保持在预定航向上,具有优良的控制效果。展开更多
文摘According to China Daily on May 1, ZTE Corp plans to strengthen its position in the European market in the fields of telecom infrastructure, smart phones and government and enterprise solutions, according to company officials.
文摘Fossil fuels may be out of fashion,but sales of foreignowned resources across Asia are expected to attract a broad mix of bidders.Some of Asia’s biggest foreignowned oil and gas assets,worth more than US$40 billion,are to be sold in 2017,with potential bidders expected to include Chinese energy companies and sovereign funds.Assets to be sold include US-based Chevron’s US$1billion(0.94 billion euros)joint ownership stake with China’s state-owned CNOOC in an offshore oil field.
文摘Lhasa has witnessed many changes a is joined the whole of China embarking on the road towards a mar-ket economy,an abrupt switch from formnerly pre-vailing planned economy.
文摘China has gained rich experience in the photovoltaic industry, and is capable of providing high-quality photovoltaic products and services at lower prices,
基金funded by Project Number INML2104 under the Interdisciplinary Center of Smart Mobility and Logistics at King Fahd University of Petroleum and Minerals.This study also was supported by the Special Research Fund BOF23KV17.
文摘Recently,Internet of Drones(IoD)has garnered significant attention due to its widespread applications.However,deploying IoD for area coverage poses numerous limitations and challenges.These include interference between neighboring drones,the need for directional antennas,and altitude restrictions for drones.These challenges necessitate the development of efficient solutions.This research paper presents a cooperative decision-making approach for an efficient IoDdeployment to address these challenges effectively.The primary objective of this study is to achieve an efficient IoDdeployment strategy thatmaximizes the coverage regionwhile minimizing interference between neighboring drones.In deployment problem,the interference increases as the number of deployed drones increases,resulting in bad quality of communication.On the other hand,deploying a few drones cannot satisfy the coverage demand.To accomplish this,an enhanced version of a concise population-based meta-heuristic algorithm,namely Improved Particle SwarmOptimization(IPSO),is applied.The objective function of IPSO is defined based on the coverage probability,which is primarily influenced by the characteristics of the antennas and drone altitude.A radio frequency(RF)model is derived to evaluate the coverage quality,considering both Line of Sight(LOS)and Non-Line of Sight(NLOS)down-link coverage probabilities for ground communication.It is assumed that each drone is equipped with a directional antenna to optimize coverage in a given region.Extensive simulations are conducted to assess the effectiveness of the proposed approach.Results demonstrate that the proposed method achieves maximum coverage with minimum transmission power.Furthermore,a comparison is made against Collaborative Visual Area Coverage Approach(CVACA),and a game-based approach in terms of coverage quality and convergence speed.The simulation results reveal that our approach outperforms both CVACA and the gamebased schemes in terms of coverage and convergence speed.Comparisons validate the superiority of our approach over existing methods.To assess the robustness of the proposed RFmodel,we have considered two distinct ranges of noise:range1 spanning from−120 to−90 dBm,and range2 spanning from−90 to−70 dBmfor different numbers of UAVs.In summary,this research presents a cooperative decision-making approach for efficient IoD deployment to address the challenges associatedwith area coverage and achieves an optimal coveragewithminimal interference.
文摘AASHTO’s guideline for geometric design of highways and similar guidelines require that roadside areas on the inside of horizontal curves be cleared of high objects to provide stopping sight distance. The guidelines have analytical models for determining the extent of clearance, known as the horizontal sightline offset or clearance offset, for simple curves. Researchers in the past have developed analytical models for clearance offsets for spiraled and reverse curves. Very few researchers developed analytical models for available sight distances for compound curves. Still missing are models for horizontal sightline offsets and locations of the offsets for compound curves. The objective of this paper is to present development of analytical models and charts for determining horizontal sightline offsets and their locations for compound curves. The paper considers curves whose component arcs are individually shorter than stopping sight distance. The resulting models and the charts have been verified with accurate values determined using graphical methods. The models and the charts will find application in geometric design of highway compound curves.
文摘Having cleared all the hurdles to enter the market, locally incorporated foreign banks declare their intentions to dive into the personal housing loan business in China A battle is brewing between domestic and locally incorporated foreign banks over
文摘Following a strong start at the Spring Edition of Intertextile Shanghai Home Textiles early this year,global industry players have turned their sights to the next international event in August 2023.As the first Autumn Edition to be held in the wake of China lifting many of its pandemicrelated border restrictions,the three-day fair will gather around 1,000 international and domestic exhibitors.
文摘基于机器人队形控制中的领航者-跟随者方法(Leader-Follower Method)和基于行为方法(Behavior-based Method),提出了一种用于多自治水下机器人(AUV)队形控制的新方法。该方法以领航者来确定整个AUV编队的前进状态,跟随者时刻跟随领航者以保持一定的队形形状。同时,领航者和跟随者都被赋予一定的行为特性以实现奔向目标、队形维持、队形转换及障碍避碰等功能。考虑到领航者在行进过程中有可能会发生意外而导致任务失败,本方法设定一特殊的跟随者令其作为候选领航者时刻跟随领航者以防万一。分别采用模糊规划器和Line of Sight(LOS)技术来实现AUV编队的障碍避碰和导航。
文摘针对非线性船舶航向控制系统,将Line of Sight(LOS)引导律与滑模控制算法相结合,设计一种航向保持滑模控制算法,通过设计合理的李雅普诺夫函数及利用其稳定性理论对系统的稳定性进行了分析,并利用"育龙"轮运动数学模型进行计算机模拟仿真,验证设计思想的可行性和控制算法的合理性及有效性。仿真结果表明,控制算法可以保证航向控制系统的渐近收敛及稳定,根据该控制算法所设计的控制器,能够使船舶航向精确的保持在预定航向上,具有优良的控制效果。
