For capturing and recycling of CO_(2)in the internal combustion engine,Rankle cycle engine can reduce the exhaust pollutants effectively under the condition of ensuring the engine thermal efficiency by using the techn...For capturing and recycling of CO_(2)in the internal combustion engine,Rankle cycle engine can reduce the exhaust pollutants effectively under the condition of ensuring the engine thermal efficiency by using the techniques of spraying water in the cylinder and optimizing the ignition advance angle.However,due to the water spray nozzle need to be installed on the cylinder,which increases the cylinder head design difficulty and makes the combustion conditions become more complicated.In this paper,a new method is presented to carry out the closing inlet and exhaust system for internal combustion engines.The proposed new method uses liquid oxygen to solidify part of cooled CO_(2)from exhaust system into dry ice and the liquid oxygen turns into gas oxygen which is sent to inlet system.The other part of CO_(2)is sent to inlet system and mixed with oxygen,which can reduce the oxygen-enriched combustion detonation tendency and make combustion stable.Computing grid of the IP52FMI single-cylinder four-stroke gasoline-engine is established according to the actual shape of the combustion chamber using KIVA-3V program.The effects of exhaust gas recirculation(EGR)rate are analyzed on the temperatures,the pressures and the instantaneous heat release rates when the EGR rate is more than 8%.The possibility of enclosing intake and exhaust system for engine is verified.The carbon dioxide trapping device is designed and the IP52FMI engine is transformed and the CO_(2)capture experiment is carried out.The experimental results show that when the EGR rate is 36%for the optimum EGR rate.When the liquid oxygen of 35.80-437.40 g is imported into the device and last 1-20 min,respectively,21.50-701.30 g dry ice is obtained.This research proposes a new design method which can capture CO_(2)for vehicular internal combustion engine.展开更多
This paper takes the right branch main channel Bridge of Huai River Bridge in Huainan as the engineering background, uses the finite element software Midas and the ANSYS to simulate and analyze the jacking constructio...This paper takes the right branch main channel Bridge of Huai River Bridge in Huainan as the engineering background, uses the finite element software Midas and the ANSYS to simulate and analyze the jacking construction of the bridge, and according to the theoretical calculation, the construction monitoring plan is developed, and the stress and deformation of the key section and part of the structure are monitored. Construction monitoring combined with 3 g network and data acquisition module, monitoring data for the real time measurement, the centralized acquisition and wireless transmission, accomplish on-line real-time monitoring of the bridge construction process, effective control of jacking construction and monitoring. The comparison between theoretical analysis and measured results shows that the simulation results are reasonable, and the construction monitoring scheme based on 3G network and data collection can be used as reference.展开更多
分析了新工科发展背景下的网络工程专业传统实验平台在实验室基础配套设施、网络链路类型和数据通信设备、实践教学开展和实验室管理维护方面存在的问题,采取使用IT厂商和开源项目提供的模拟器和虚拟机软件方法解决这些问题,对比了思科P...分析了新工科发展背景下的网络工程专业传统实验平台在实验室基础配套设施、网络链路类型和数据通信设备、实践教学开展和实验室管理维护方面存在的问题,采取使用IT厂商和开源项目提供的模拟器和虚拟机软件方法解决这些问题,对比了思科Packet Tracer模拟器、开源项目GNS3、Oracle VM VirtualBox和EVE-NG的软件工作特征,描述了网络工程专业核心课程在虚拟仿真实验平台上的参考案例和部署建议,说明了基于上述模拟器和虚拟机软件搭建的网络工程专业虚拟仿真实验平台进行虚实结合实验是完全可行和有效的。展开更多
Drones have become indispensable tools in various domains, from surveillance and environmental monitoring to disaster response and communication relay. However, their growing use in critical missions necessitates robu...Drones have become indispensable tools in various domains, from surveillance and environmental monitoring to disaster response and communication relay. However, their growing use in critical missions necessitates robust security measures to protect against potential threats and ensure the integrity of operations. This research presents a novel secure architecture for a swarm of drones deployed on surveillance missions. Leveraging a reliable foundation established through Delaunay triangulation for communication among drones, this work introduces advanced security protocols to enhance the protection and integrity of the network. The architecture employs a mesh network topology connecting six drones, each configured for specific surveillance tasks, including perimeter monitoring, area scanning, thermal imaging, traffic observation, communication relay, and incident response. The mesh network design ensures extended coverage, redundancy, load balancing, and self-configuration, significantly improving reliability and resilience. Security validation was conducted using GNS3 and Ettercap, simulating various vulnerability scenarios. Comparative performance analysis between a classic drone network and the proposed secure mesh network demonstrates superior traffic management and robustness against potential attacks. The results underscore the architecture’s suitability for secure and reliable operations in critical surveillance environments.展开更多
基金Supported by National Natural Science Foundation of China(Grant No.51176082)Importation and Development of High-Caliber Talents Project of Beijing Municipal Institutions of China(Grant No.CIT&TCD20140311)Beijing Municipal Natural Science Foundation of China(Grant No.SQKZ201510016004)
文摘For capturing and recycling of CO_(2)in the internal combustion engine,Rankle cycle engine can reduce the exhaust pollutants effectively under the condition of ensuring the engine thermal efficiency by using the techniques of spraying water in the cylinder and optimizing the ignition advance angle.However,due to the water spray nozzle need to be installed on the cylinder,which increases the cylinder head design difficulty and makes the combustion conditions become more complicated.In this paper,a new method is presented to carry out the closing inlet and exhaust system for internal combustion engines.The proposed new method uses liquid oxygen to solidify part of cooled CO_(2)from exhaust system into dry ice and the liquid oxygen turns into gas oxygen which is sent to inlet system.The other part of CO_(2)is sent to inlet system and mixed with oxygen,which can reduce the oxygen-enriched combustion detonation tendency and make combustion stable.Computing grid of the IP52FMI single-cylinder four-stroke gasoline-engine is established according to the actual shape of the combustion chamber using KIVA-3V program.The effects of exhaust gas recirculation(EGR)rate are analyzed on the temperatures,the pressures and the instantaneous heat release rates when the EGR rate is more than 8%.The possibility of enclosing intake and exhaust system for engine is verified.The carbon dioxide trapping device is designed and the IP52FMI engine is transformed and the CO_(2)capture experiment is carried out.The experimental results show that when the EGR rate is 36%for the optimum EGR rate.When the liquid oxygen of 35.80-437.40 g is imported into the device and last 1-20 min,respectively,21.50-701.30 g dry ice is obtained.This research proposes a new design method which can capture CO_(2)for vehicular internal combustion engine.
文摘This paper takes the right branch main channel Bridge of Huai River Bridge in Huainan as the engineering background, uses the finite element software Midas and the ANSYS to simulate and analyze the jacking construction of the bridge, and according to the theoretical calculation, the construction monitoring plan is developed, and the stress and deformation of the key section and part of the structure are monitored. Construction monitoring combined with 3 g network and data acquisition module, monitoring data for the real time measurement, the centralized acquisition and wireless transmission, accomplish on-line real-time monitoring of the bridge construction process, effective control of jacking construction and monitoring. The comparison between theoretical analysis and measured results shows that the simulation results are reasonable, and the construction monitoring scheme based on 3G network and data collection can be used as reference.
文摘分析了新工科发展背景下的网络工程专业传统实验平台在实验室基础配套设施、网络链路类型和数据通信设备、实践教学开展和实验室管理维护方面存在的问题,采取使用IT厂商和开源项目提供的模拟器和虚拟机软件方法解决这些问题,对比了思科Packet Tracer模拟器、开源项目GNS3、Oracle VM VirtualBox和EVE-NG的软件工作特征,描述了网络工程专业核心课程在虚拟仿真实验平台上的参考案例和部署建议,说明了基于上述模拟器和虚拟机软件搭建的网络工程专业虚拟仿真实验平台进行虚实结合实验是完全可行和有效的。
文摘Drones have become indispensable tools in various domains, from surveillance and environmental monitoring to disaster response and communication relay. However, their growing use in critical missions necessitates robust security measures to protect against potential threats and ensure the integrity of operations. This research presents a novel secure architecture for a swarm of drones deployed on surveillance missions. Leveraging a reliable foundation established through Delaunay triangulation for communication among drones, this work introduces advanced security protocols to enhance the protection and integrity of the network. The architecture employs a mesh network topology connecting six drones, each configured for specific surveillance tasks, including perimeter monitoring, area scanning, thermal imaging, traffic observation, communication relay, and incident response. The mesh network design ensures extended coverage, redundancy, load balancing, and self-configuration, significantly improving reliability and resilience. Security validation was conducted using GNS3 and Ettercap, simulating various vulnerability scenarios. Comparative performance analysis between a classic drone network and the proposed secure mesh network demonstrates superior traffic management and robustness against potential attacks. The results underscore the architecture’s suitability for secure and reliable operations in critical surveillance environments.
