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说“鱼翔浅底”中的“翔”
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作者 宋子伟 《语文天地》 2003年第02M期8-8,共1页
关键词 “鱼浅底” “翔” 高中 《沁园春·长沙》 郭沫若 语文 阅读
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发挥国防经济优势 促进西部军民结合产业发展——《翔式道路:西部技术产业军地融合发展路径》序 被引量:4
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作者 梁清文 《西安财经学院学报》 2010年第2期123-126,共4页
《翔式道路:西部技术产业军地融合发展路径》遵循经济非均衡发展的客观规律,提出发挥军地融合高新技术产业优势促进西部产业结构优化升级路径,即"翔式道路"。关于发展军地融合高新技术产业是西部地区产业结构优化升级与军民... 《翔式道路:西部技术产业军地融合发展路径》遵循经济非均衡发展的客观规律,提出发挥军地融合高新技术产业优势促进西部产业结构优化升级路径,即"翔式道路"。关于发展军地融合高新技术产业是西部地区产业结构优化升级与军民结合、寓军于民发展的战略基点的观点,"翔式道路"的概括,以及实施"翔式道路"的措施等理论对策等,有重要的实践意义与学术价值。 展开更多
关键词 国防经济 西部地区 “翔式道路” 军民结合产业
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不同香型白酒在陶缸陈酿过程中的变化研究
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作者 祝成 蒋燕明 +9 位作者 管莹 易翔 左可成 万朕 柯锋 詹苏 孙婷婷 施鹏 罗高建 童国强 《酿酒科技》 2023年第11期70-76,共7页
为了弄清楚不同香型白酒在陶缸陈酿过程中的变化情况,更好地指导原酒的科学贮存,选取3种香型白酒(清香、浓香、酱香)分别放入陶缸中进行陈酿3年,研究3种香型白酒在陶缸陈酿过程中酒精度、金属元素、微量风味成分和感官风格的变化情况。... 为了弄清楚不同香型白酒在陶缸陈酿过程中的变化情况,更好地指导原酒的科学贮存,选取3种香型白酒(清香、浓香、酱香)分别放入陶缸中进行陈酿3年,研究3种香型白酒在陶缸陈酿过程中酒精度、金属元素、微量风味成分和感官风格的变化情况。随着储存时间的延长,酯类物质含量总体呈现下降趋势,三年左右趋于平衡,酸类物质缓慢增加,高级醇含量轻微下降;Na、K、Mg、Fe、Zn等金属元素显示出升高的趋势;感官评分呈一定的增加趋势。 展开更多
关键词 白酒 微量成分 陶缸陈酿
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Flight Range Optimization of Extended Range Guided Munitions 被引量:1
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作者 夏群力 祁载康 林德福 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期383-388,共6页
By the study of extended range guided munitions (ERGM) trajectory characteristics, ERGM free-flight and glide trajectory characteristics are revealed and illustrated. On the basis of free-flight trajectory mathematica... By the study of extended range guided munitions (ERGM) trajectory characteristics, ERGM free-flight and glide trajectory characteristics are revealed and illustrated. On the basis of free-flight trajectory mathematical model, a two-parameter optimization problem of quadrant elevation and rocket ignition time is studied. Using the atmosphere mathematical model, the best glide-starting point of the downward trajectory is determined. With an optimal control mathematical model, the ERGM optimal glide trajectory is obtained. 展开更多
关键词 free-flight trajectory parameter optimization optimal glide trajectory
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Analysis on Soil Nutrients and Formulated Fertilization Recommend of Rapeseed in Linxiang County,Yunnan Province
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作者 赵应学 杨景华 +1 位作者 王建新 鲁耀 《Agricultural Science & Technology》 CAS 2015年第2期281-284,共4页
[Objective] The aim was to learn the soil nutrient status of the main rapeseed planting areas in Linxiang County,Yunnan Province,and propose full production potential of soil and fertilizer recommendations,thereby pro... [Objective] The aim was to learn the soil nutrient status of the main rapeseed planting areas in Linxiang County,Yunnan Province,and propose full production potential of soil and fertilizer recommendations,thereby promoting local rapeseed production and income.[Method] The soil samples collected in field and tested in laboratory,with amount of fertilizer needed by rapeseed investigation were combined to calculate the formulated fertilization.[Result] Most of the soil organic matter and nutrient content of NPK were at the middle or higher level in the main rapeseed planting areas in Linxiang County.However,more than half of the soils were acidic or strongly acidic,and the soil p H maintained below 5.5.The shortage soil boron was more serious,the average content and nearly 60% of the sample of soil available boron were less than 0.5 mg/kg.[Conclusion] The formulated fertilization recommendations were identified as follows.To achieve the goal of 3 750 kg/hm^2240,150 and 75 kg/ha,if the application amount of manure was 15 000 kg/h,the total fertilizer N,P2O5,K2 O amount applied were separately 300,195 and 195 kg/hm^2.The chemical fertilizer N,P2O5,K2 O amount applied should be respectively 240,150 and 75 kg/hm^2,if the application amount of manure was 15 000 kg/hm^2.The nitrogen species of urea(containing N 46%),causing weakest effect on soil acidification,was selected and applied about with 525 kg/hm^2.The alkaline calcium magnesium phosphate(P2O520%),alternating superphosphate,was applied with about 750 kg/hm^2.Sulfuric acid potassium(K2O 50%) was applied with about 150 kg/hm^2.About 7.5kg/hm^2 borax was applied into soil as basal fertilizer,while spraying 7.5 kg/hm^2 fluid boron at the Bolting stag. 展开更多
关键词 Linxiang county RAPESEED Soil nutrient Formulated fertilization
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The relation between modes of lithologic association and interlayer-gliding structures in coal mine 被引量:6
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作者 LE Qi-lang CHEN Ping YANG Wei-min 《Journal of Coal Science & Engineering(China)》 2010年第1期47-52,共6页
As a case study of the Panji No.1 Coal Mine in Anhui Province, based on thesite measured and statistical data, summarized the lithologic associations, characteristicsand distribution laws of interlayer-gliding structu... As a case study of the Panji No.1 Coal Mine in Anhui Province, based on thesite measured and statistical data, summarized the lithologic associations, characteristicsand distribution laws of interlayer-gliding structures and tectonic coal in the No.11-2 coalseams.The results show that 9 modes of lithologic association can form interlayer-glidingstructures.It is more easy for rock slip to occur when the lithologic associations are mainroof + coal seam + immediate floor type, compound roof+immediate roof + coal seam +immediate floor type and immediate roof + coal seam + immediate floor type.Lithologicassociations of roof and floor are the precondition to the formation of interlayer-glidingstructures. 展开更多
关键词 coal seam roof and floor modes of lithologic association interlayer-gliding structure Panji No.1 Coal Mine
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摇头飞椅挠性吊挂件的安全可靠性比对分析
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作者 张宇光 姚俊 蔡昶 《质量与标准化》 2022年第2期41-44,共4页
摇头飞椅挠性吊挂件的常用方式是圆环链或钢丝绳。本文以圆环链和钢丝绳为研究对象,从承载能力、抗挤压和碰撞能力等几个方面对其使用过程中的安全可靠性进行了比对分析,并就如何提高挠性吊挂件在使用过程中的安全可靠性提出了相关建议。
关键词 摇头飞椅 挠性吊挂件 安全可靠性
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Unmanned wave glider heading model identification and control by artificial fish swarm algorithm 被引量:2
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作者 WANG Lei-feng LIAO Yu-lei +2 位作者 LI Ye ZHANG Wei-xin PAN Kai-wen 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第9期2131-2142,共12页
We introduce the artificial fish swarm algorithm for heading motion model identification and control parameter optimization problems for the“Ocean Rambler”unmanned wave glider(UWG).First,under certain assumptions,th... We introduce the artificial fish swarm algorithm for heading motion model identification and control parameter optimization problems for the“Ocean Rambler”unmanned wave glider(UWG).First,under certain assumptions,the rigid-flexible multi-body system of the UWG was simplified as a rigid system composed of“thruster+float body”,based on which a planar motion model of the UWG was established.Second,we obtained the model parameters using an empirical method combined with parameter identification,which means that some parameters were estimated by the empirical method.In view of the specificity and importance of the heading control,heading model parameters were identified through the artificial fish swarm algorithm based on tank test data,so that we could take full advantage of the limited trial data to factually describe the dynamic characteristics of the system.Based on the established heading motion model,parameters of the heading S-surface controller were optimized using the artificial fish swarm algorithm.Heading motion comparison and maritime control experiments of the“Ocean Rambler”UWG were completed.Tank test results show high precision of heading motion prediction including heading angle and yawing angular velocity.The UWG shows good control performance in tank tests and sea trials.The efficiency of the proposed method is verified. 展开更多
关键词 unmanned wave glider artificial fish swarm algorithm heading model parameters identification control parameters optimization
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A Potential Flow Based Flight Simulator for an Underwater Glider 被引量:3
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作者 Surasak Phoemsapthawee Marc Le Boulluec +1 位作者 Jean-Marc Laurens Fran ois Deniset 《Journal of Marine Science and Application》 2013年第1期112-121,共10页
Underwater gliders are recent innovative types of autonomous underwater vehicles (AUVs) used in ocean exploration and observation. They adjust their buoyancy to dive and to return to the ocean surface. During the ch... Underwater gliders are recent innovative types of autonomous underwater vehicles (AUVs) used in ocean exploration and observation. They adjust their buoyancy to dive and to return to the ocean surface. During the change of altitude, they use the hydrodynamic forces developed by their wings to move forward. Their flights are controlled by changing the position of their centers of gravity and their buoyancy to adjust their trim and heel angles. For better flight control, the understanding of the hydrodynamic behavior and the flight mechanics of the underwater glider is necessary. A 6-DOF motion simulator is coupled with an unsteady potential flow model for this purpose. In some specific cases, the numerical study demonstrates that an inappropriate stabilizer dimension can cause counter-steering behavior. The simulator can be used to improve the automatic flight control. It can also be used for the hydrodynamic design optimization of the devices. 展开更多
关键词 underwater glider potential flow Newton-Euler equation autonomous underwater vehicles (AUVs) flight simulator
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Energy Storage System with Ultracapacitors for Thermal Underwater Glider
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作者 王乐萍 张连洪 姜军鹏 《Transactions of Tianjin University》 EI CAS 2013年第2期98-102,共5页
A power system with proton exchange membrane fuel cells (PEMFC) was designed for thermal underwater glider.Heat generated by PEMFC is used as the propulsion power of the glider,and the electricity is used in the contr... A power system with proton exchange membrane fuel cells (PEMFC) was designed for thermal underwater glider.Heat generated by PEMFC is used as the propulsion power of the glider,and the electricity is used in the control and sensor system.An electric energy storage system (ESS) is required which possesses high power density with good cycle life.Ultracapacitors which exhibit high power density and cycle life are considered as energy storage devices.Simulations based on a specific voyage condition indicate that ESS with ultracapacitors has positive effects on reducing the output power demand of PEMFC and lightening the power system.Experimental results show that the state of charge (SOC) is related to the capacitance and resistance in ultracapacitor ESS. 展开更多
关键词 thermal underwater glider proton exchange membrane fuel cell ultracapacitor energy storage system state of charge
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Chinese Athlete Breaks 110-meter Hurdles World Record
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作者 Qing Qing & Xu Jingxing 《China & The World Cultural Exchange》 2006年第9期42-43,共2页
Liu Xiang of China set a world mark in the 110-meter hurdles on July 12, breaking the record he shared with Britain’s Colin Jackson. Liu’s time of 12.88 seconds at the IAAF Super Grand Prix athletics meeting in Laus... Liu Xiang of China set a world mark in the 110-meter hurdles on July 12, breaking the record he shared with Britain’s Colin Jackson. Liu’s time of 12.88 seconds at the IAAF Super Grand Prix athletics meeting in Laussane, Switzerland was 0.03 better than the record he matched in winning gold at the 2004 Athens Olympics. 展开更多
关键词 中国 田径运动员 110米跨栏跑 世界纪录
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台军世纪初年计划多
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作者 周义 周丽 《当代海军》 2001年第6期7-7,共1页
据最新消息,台湾2001年度“国防”机密预算总额达583亿元新台币。这些经费将主要用于政治作战、情报业务、战备通信、军事补给修护、武器装备、军事设施、特种军事人员、科学研究、军事工程及设备等九方面。
关键词 台湾省 军队建设 军事预算 “庐山”计划 “翔升”计划 “脉护”计划
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Quasi-equilibrium glide adaptive guidance for hypersonic vehicles 被引量:31
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作者 XU MingLiang CHEN KeJun +1 位作者 LIU LuHua TANG GuoJian 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第3期856-866,共11页
The entry-glide guidance strategy for hypersonic vehicles that can satisfy both terminal and path constraints is investigated in this paper.We propose a quasi-equilibrium glide adaptive guidance methodology based on t... The entry-glide guidance strategy for hypersonic vehicles that can satisfy both terminal and path constraints is investigated in this paper.We propose a quasi-equilibrium glide adaptive guidance methodology based on the quasi-equilibrium glide condition(QEGC),which innovatively utilizes the quasi-equilibrium glide phenomenon in lifting entry.With the aid of QEGC,both range and terminal velocity can be predicted analytically with high precision.The path constraints are converted into angle of attack constraints,which has been difficult to realize by using traditional predictive guidance methods.The algorithm is independent of the standard trajectory.All the guidance commands,including the bank angle and the angle of attack,are calculated analytically in real time,which endows the algorithm with sufficient adapbility.The results of a CAV-H vehicle guidance test show that the algorithm leads the vehicle along a quasi-equilibrium glide trajectory satisfying both the terminal and path constraints and has sufficient flexibility for occasional mission changes.Furthermore,the robustness of the guidance algorithm under disturbances is validated through a Monte Carlo simulation. 展开更多
关键词 hypersonic vehicles entry guidance quasi-equilibrium glide adaptive guidance analytical predictor-corrector (APC)
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Dynamic modeling of a wave glider 被引量:7
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作者 Chun-lin ZHOU Bo-xing WANG +2 位作者 Hong-xiang ZHOU Jing-lan LI Rong XIONG 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2017年第9期1295-1304,共10页
We propose a method to establish a dynamic model for a wave glider, a wave-propelled sea surface vehicle that can make use of wave energy to obtain thrust. The vehicle, composed of a surface float and a submerged glid... We propose a method to establish a dynamic model for a wave glider, a wave-propelled sea surface vehicle that can make use of wave energy to obtain thrust. The vehicle, composed of a surface float and a submerged glider in sea water, is regarded as a two-particle system. Kane's equations are used to establish the dynamic model. To verify the model, the design of a testing prototype is proposed and pool trials are conducted. The speeds of the vehicle under different sea conditions can be computed using the model, which is verified by pool trials. The optimal structure parameters useful for vehicle designs can also be obtained from the model. We illustrate how to build an analytical dynamics model for the wave glider, which is a crucial basis for the vehicle's motion control. The dynamics model also provides foundations for an off-line simulation of vehicle performance and the optimization of its mechanical designs. 展开更多
关键词 Wave-propelled vehicle Dynamic modeling Sea surface vehicle Wave glider
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Morphology, flight performance, and water crossing tendencies of Afro-Palearctic raptors during migration 被引量:5
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作者 Nicolantonio AGOSTINI Michele PANUCCIO Cristian PASQUARETTA 《Current Zoology》 SCIE CAS CSCD 2015年第6期951-958,共8页
Raptors primarily use soaring-gliding flight which exploits thermals and ridge lifts over land to reduce energetic costs However during migration, these birds often have to cross water surfaces where thermal currents ... Raptors primarily use soaring-gliding flight which exploits thermals and ridge lifts over land to reduce energetic costs However during migration, these birds often have to cross water surfaces where thermal currents are weak; during these times, birds mainly use flapping (powered) flight which increases energy consumption and mortality risk. As a result, some species have evolved strategies to reduce the amount of time spent over water by taking extensive detours over land. In this paper, we con- ducted a meta-analysis of water-crossing tendencies in Afro-Palearctic migrating raptors in relation to their morphology, their flight performance, and their phylogenetic relationships. In particular, we considered the aspect ratio (calculated as the wing span squared divided by wing area), the energetic cost of powered flight, and the maximum water crossing length regularly performed by adult birds. Our results suggest that energy consumption during powered flight predominately affects the ability of raptors to fly over water surfaces 展开更多
关键词 Water crossing Aspect ratio Powered flight MIGRATION RAPTORS Wing tip
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Steering control for underwater gliders 被引量:1
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作者 You LIU Qing SHEN +1 位作者 Dong-li MA Xiang-jiang YUAN 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2017年第7期898-914,共17页
Steering control for an autonomous underwater glider (AUG) is very challenging due to its changing dynamic char- acteristics such as payload and shape. A good choice to solve this problem is online system identifica... Steering control for an autonomous underwater glider (AUG) is very challenging due to its changing dynamic char- acteristics such as payload and shape. A good choice to solve this problem is online system identification via in-field trials to capture current dynamic characteristics for control law reconfiguration. Hence, an online polynomial estimator is designed to update the yaw dynamic model of the AUG, and an adaptive model predictive control (MPC) controller is used to calculate the optimal control command based on updated estimated parameters. The MPC controller uses a quadratic program (QP) to compute the optimal control command based on a user-defined cost function. The cost function has two terms, focusing on output reference tracking and move suppression of input, respectively. Move-suppression performance can, at some level, represent energy-saving performance of the MPC controller. Users can balance these two competitive control performances by tuning weights. We have compared the control performance using the second-order polynomial model to that using the filth-order polynomial model, and found that the tbrmer cannot capture the main characteristics of yaw dynamics and may result in vibration during the flight. Both processor-in-loop (PIL) simulations and in-lake tests are presented to validate our steering control performance. 展开更多
关键词 Autonomous underwater glider (AUG) Online system identification Steering control Adaptive control OPTIMALCONTROL Energy saving control Processor-in-loop (PIL)
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A space-saving steering method for underwater gliders in lake monitoring
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作者 Yu-shi ZHU Can-jun YANG +2 位作者 Shi-jun WU Qing LI Xiao-le XU 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2017年第4期485-497,共13页
An increasing number of underwater gliders have been applied to lake monitoring. Lakes have a limited vertical space. Therefore, good space-saving capacity is required for underwater gliders to enlarge the spacing bet... An increasing number of underwater gliders have been applied to lake monitoring. Lakes have a limited vertical space. Therefore, good space-saving capacity is required for underwater gliders to enlarge the spacing between monitoring waypoints. This paper presents a space-saving steering method under a small pitch angle (SPA) for appearance-fixed underwater gliders. Steering under an SPA increases the steering angle in per unit vertical space. An amended hydrodynamic model for both small and large attack angles is presented to help analyze the steering process. Analysis is conducted to find the optimal parameters of net buoyancy and roll angle for steering under an SPA. A lake trial with a prototype tiny underwater glider (TUG) is conducted to inspect the applicability of the presented model. The trial results show that steering under an SPA saves vertical space, unlike that under a large pitch angle. Simulation results of steering are consistent with the trial results. In addition, multiple-waypoint trial shows that monitoring with steering under an SPA covers a larger horizontal displacement than that without steering. 展开更多
关键词 Underwater glider Lake monitoring Space-saving Steering method Small pitch angle (SPA) Hydrodynamics
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