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Uncertainty quantification of mechanism motion based on coupled mechanism—motor dynamic model for ammunition delivery system
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作者 Jinsong Tang Linfang Qian +3 位作者 Longmiao Chen Guangsong Chen Mingming Wang Guangzu Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期125-133,共9页
In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this method.The main contribution is to pro... In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this method.The main contribution is to propose a novel mechanism-motor coupling dynamic modeling method,in which the relationship between mechanism motion and motor rotation is established according to the geometric coordination of the system.The advantages of this include establishing intuitive coupling between the mechanism and motor,facilitating the discussion for the influence of both mechanical and electrical parameters on the mechanism,and enabling dynamic simulation with controller to take the randomness of the electric load into account.Dynamic simulation considering feedback control of ammunition delivery system is carried out,and the feasibility of the model is verified experimentally.Based on probability density evolution theory,we comprehensively discuss the effects of system parameters on mechanism motion from the perspective of uncertainty quantization.Our work can not only provide guidance for engineering design of ammunition delivery mechanism,but also provide theoretical support for modeling and uncertainty quantification research of mechatronics system. 展开更多
关键词 ammunition delivery system Electromechanical coupling dynamics Uncertainty quantification Generalized probability density evolution
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An aerial ammunition ad hoc network collaborative localization algorithm based on relative ranging and velocity measurement in a highly-dynamic topographic structure 被引量:1
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作者 Hao Wu Peng-fei Wu +2 位作者 Zhang-song Shi Shi-yan Sun Zhong-hong Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第7期231-248,共18页
In the internet of battlefield things, ammunition is becoming networked and intelligent, which depends on location information. Therefore, this paper focuses on the self-organized network collaborative localization of... In the internet of battlefield things, ammunition is becoming networked and intelligent, which depends on location information. Therefore, this paper focuses on the self-organized network collaborative localization of munitions with an aerial three-dimensional(3D) highly-dynamic topographic structure under a satellite denied environment. As for aerial networked munitions, the measurement of munitions is objectively incomplete due to the degenerated and interrupted link of munitions. For this reason, a cluster-oriented collaborative localization method is put forward in this paper. Multidimensional scaling(MDS) was first integrated with a trilateration localization method(TLM) to construct a relative localization algorithm for determining the relative location of a mobile cluster network. The information related to relative velocity was then combined into a collaborative localization framework to devise a TLM-vMDS algorithm. Finally, an iterative refinement algorithm based on scaling by majorizing a complicated function(SMACOF) was employed to effectively eliminate the influence of incomplete link observation on localization accuracy. Compared with the currently available advanced algorithms, the proposed TLM-vMDS algorithm achieves higher localization accuracy and faster convergence for a cluster of extensively networked munitions, and also offers better numerical stability and robustness for highspeed motion models. 展开更多
关键词 Highly-dynamic topographic structure MDS Relative ranging Aerial ammunition ad hoc network
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Production of Partial New-typed Brassica Napus by Introgression of Genomic Components from B. rapa and B. carinata 被引量:1
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作者 栗茂腾 刘建民 +2 位作者 王艳婷 余龙江 孟金陵 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第5期460-468,共9页
A breeding strategy for widening the germplasm of Brassica napus was proposed by introgression of the A^r subgenome of B. rapa (A^rA^r) and C^c of B. carinata (B^cB^cC^cC^c) into natural B. napus (AnAncncn). The... A breeding strategy for widening the germplasm of Brassica napus was proposed by introgression of the A^r subgenome of B. rapa (A^rA^r) and C^c of B. carinata (B^cB^cC^cC^c) into natural B. napus (AnAncncn). The progenies with 38 chromosomes that were derived from the self-pollinated seeds of pentaploid hybrids (A^rA^nB^cC^cC^n) were used for further research. Some of the partial new-typed B. napus showed normal meiotic behavior, high portion of germinated pollen and normal embryological development. This indicates that the selected new-typed B. napus had a balanced genetic base. Molecular analysis showed that about 50% of the genome in the new-typed B. napus was replaced by A^r and C^c subgenome from B. rapa and B. carinata. Considering the genetic diversity among different lines of new-typed B. napus, it was deduced that the introgression of the genomic components from B, rapa and B. carinata could widen the genetic diversity of rapeseed. 展开更多
关键词 new-typed B. napus pollen germination embryo sac development genome introgression genetic distance
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Numerical simulation and optimized design of cased telescoped ammunition interior ballistic 被引量:10
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作者 Jia-gang Wang Yong-gang Yu +1 位作者 Liang-liang Zhou Rui Ye 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2018年第2期119-125,共7页
In order to achieve the optimized design of a cased telescoped ammunition(CTA) interior ballistic design,a genetic algorithm was introduced into the optimal design of CTA interior ballistics with coupling the CTA inte... In order to achieve the optimized design of a cased telescoped ammunition(CTA) interior ballistic design,a genetic algorithm was introduced into the optimal design of CTA interior ballistics with coupling the CTA interior ballistic model. Aiming at the interior ballistic characteristics of a CTA gun, the goal of CTA interior ballistic design is to obtain a projectile velocity as large as possible. The optimal design of CTA interior ballistic is carried out using a genetic algorithm by setting peak pressure, changing the chamber volume and gun powder charge density. A numerical simulation of interior ballistics based on a 35 mm CTA firing experimental scheme was conducted and then the genetic algorithm was used for numerical optimization. The projectile muzzle velocity of the optimized scheme is increased from 1168 m/s for the initial experimental scheme to 1182 m/s. Then four optimization schemes were obtained with several independent optimization processes. The schemes were compared with each other and the difference between these schemes is small. The peak pressure and muzzle velocity of these schemes are almost the same. The result shows that the genetic algorithm is effective in the optimal design of the CTA interior ballistics. This work will be lay the foundation for further CTA interior ballistic design. 展开更多
关键词 Cased telescoped ammunition INTERIOR BALLISTICS GUNPOWDER Optimization GENETIC algorithm
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Non standard pallet series designing problem in ammunition supply system 被引量:2
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作者 LiLiangchun GuoMin WangHongwei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第1期74-77,共4页
According to the compound packing problem in ammunition supply system in our army, the non-standard pallet series design model is proposed, and the original problem that can be solved as a set cover problem with a nes... According to the compound packing problem in ammunition supply system in our army, the non-standard pallet series design model is proposed, and the original problem that can be solved as a set cover problem with a nested bin-packing problem, is analyzed, then two heuristic algorithms are applied to solve the problem. 展开更多
关键词 ammunition supply PALLET minimum set covering bin-packing.
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Spatiotemporal Characteristics of Rural Labor Migration in China: Evidence from the Migration Stability under New-type Urbanization 被引量:7
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作者 DENG Wei ZHANG Shaoyao +3 位作者 ZHOU Peng PENG Li LIU Ying WAN Jiangjun 《Chinese Geographical Science》 SCIE CSCD 2020年第5期749-764,共16页
Although the factors affecting rural-to-urban migration have been discussed and analyzed in detail, few studies have examined the spatiotemporal dynamic characteristics of rural migrants’ employment and working-citie... Although the factors affecting rural-to-urban migration have been discussed and analyzed in detail, few studies have examined the spatiotemporal dynamic characteristics of rural migrants’ employment and working-cities in the post-immigrate era, which is essential for the citizenization and social integration of new-type urbanization in China. This study uses survey data from rural migration laborers across the eastern, central, and western China to construct a comprehensive labor migration stability index, and compares the determinants of the migration stability of rural labor among cities and industries using Geodetector. The results are as follows: 1) Compared with the midwestern cities, eastern cities have attracted younger and more skilled rural labor, and industries with higher technical content have higher migration stability among rural laborers. 2) Rural laborers more often adapt to changes by changing employment instead of changing working-cities. 3) The individual experiences of rural laborers and urban characteristics have significant impacts on the stability of migration, and family and societal guanxi(Chinese interpersonal relationships) enhance migration stability. 4) A unified labor market and convenient transportation have somewhat slowed industrial transfers and labor backflow. This study enhances our understanding of the roles of industrial transfer and new-type urbanization in shaping the labor geography landscape and provides policy implications for the promotion of people-oriented urbanization. 展开更多
关键词 migration stability rural labor Geodetector spatiotemporal characteristics new-type urbanization
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Intelligent Ammunition Detection and Classification System Using Convolutional Neural Network 被引量:6
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作者 Gulzar Ahmad Saad Alanazi +4 位作者 Madallah Alruwaili Fahad Ahmad Muhammad Adnan Khan Sagheer Abbas Nadia Tabassum 《Computers, Materials & Continua》 SCIE EI 2021年第5期2585-2600,共16页
Security is a significant issue for everyone due to new and creative ways to commit cybercrime.The Closed-Circuit Television(CCTV)systems are being installed in offices,houses,shopping malls,and on streets to protect ... Security is a significant issue for everyone due to new and creative ways to commit cybercrime.The Closed-Circuit Television(CCTV)systems are being installed in offices,houses,shopping malls,and on streets to protect lives.Operators monitor CCTV;however,it is difficult for a single person to monitor the actions of multiple people at one time.Consequently,there is a dire need for an automated monitoring system that detects a person with ammunition or any other harmful material Based on our research and findings of this study,we have designed a new Intelligent Ammunition Detection and Classification(IADC)system using Convolutional Neural Network(CNN).The proposed system is designed to identify persons carrying weapons and ammunition using CCTV cameras.When weapons are identified,the cameras sound an alarm.In the proposed IADC system,CNN was used to detect firearms and ammunition.The CNN model which is a Deep Learning technique consists of neural networks,most commonly applied to analyzing visual imagery has gained popularity for unstructured(images,videos)data classification.Additionally,this system generates an early warning through detection of ammunition before conditions become critical.Hence the faster and earlier the prediction,the lower the response time,loses and potential victims.The proposed IADC system provides better results than earlier published models like VGGNet,OverFeat-1,OverFeat-2,and OverFeat-3. 展开更多
关键词 CCTV CNN IADC deep learning intelligent ammunition detection DnCNN
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Barrier Lyapunov functions-based dynamic surface control with tracking error constraints for ammunition manipulator electro-hydraulic system 被引量:2
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作者 Shou-Cheng Nie Lin-Fang Qian +2 位作者 Long-Miao Chen Ling-Fei Tian Quan Zou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第3期836-845,共10页
This paper focuses on the dynamic tracking control of ammunition manipulator system. A standard state space model for the ammunition manipulator electro-hydraulic system(AMEHS) with inherent nonlinearities and uncerta... This paper focuses on the dynamic tracking control of ammunition manipulator system. A standard state space model for the ammunition manipulator electro-hydraulic system(AMEHS) with inherent nonlinearities and uncertainties considered was established. To simultaneously suppress the violation of tracking error constraints and the complexity of differential explosion, a barrier Lyapunov functionsbased dynamic surface control(BLF-DSC) method was proposed for the position tracking control of the ammunition manipulator. Theoretical analysis prove the stability of the closed-loop overall system and the tracking error converges to a prescribed neighborhood asymptotically. The effectiveness and dynamic tracking performance of the proposed control strategy is validated via simulation and experimental results. 展开更多
关键词 ammunition manipulator Electro-hydraulic system Error constraints Tracking control
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Statistical variability and fragility assessment of ballistic perforation of steel plates for 7.62 mm AP ammunition 被引量:2
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作者 Mark G.Stewart Michael DNetherton 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第3期503-513,共11页
The paper describes field test results of 7.62×51 mm M61 AP(armour piercing) ammunition fired into mild steel targets at an outdoor range.The targets varied from 10 mm to 32 mm in thickness.The tests recorded pen... The paper describes field test results of 7.62×51 mm M61 AP(armour piercing) ammunition fired into mild steel targets at an outdoor range.The targets varied from 10 mm to 32 mm in thickness.The tests recorded penetration depth,probability of perforation(i.e.,complete penetration),muzzle and impact velocities,bullet mass,and plate yield strength and hardness.The measured penetration depth exhibited a variability of approximately±12%.The paper then compared ballistic test results with predictive models of steel penetration depth and thickness to prevent perforation.Statistical parameters were derived for muzzle and impact velocity,bullet mass,plate thickness,plate hardness,and model error.A Monte-Carlo probabilistic analysis was then developed to estimate the probability of plate perforation of 7.62 mm M61 AP ammunition for a range of impact velocities,and for mild steels,and High Hardness Armour(HHA) plates.This perforation fragility analysis considered the random variability of impact velocity,bullet mass,plate thickness,plate hardness,and model error.Such a probabilistic analysis allows for reliability-based design,where,for example,the plate thickness with 95% reliability(i.e.only 1 in 20 shots will penetrate the wall) can be estimated knowing the probabilistic distribution of perforation.Hence,it was found that the plate thickness to ensure a low 5% probability of perforation needs to be 11-15% thicker than required to have a 50/50 chance of perforation for mild steel plates.Plates would need to be 20-30% thicker if probability of perforation is reduced to zero. 展开更多
关键词 BALLISTICS PROBABILITY STATISTICS Steel plates Armour steel ammunition Experimental PERFORATION
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Influence of chamber misalignment on cased telescoped(CT) ammunition accuracy 被引量:8
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作者 D.CORRIVEAU C.FLORIN PETRE 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2016年第2期117-123,共7页
As part of a research program, it was desired to better understand the impact of the rotating chamber alignment with the barrel throat on the precision and accuracy of a novel cased telescoped(CT) ammunition firing ri... As part of a research program, it was desired to better understand the impact of the rotating chamber alignment with the barrel throat on the precision and accuracy of a novel cased telescoped(CT) ammunition firing rifle. In order to perform the study, a baseline CT ammunition chamber which was concentric with a Mann barrel bore was manufactured. Additionally, six chambers were manufactured with an offset relative to the barrel bore. These chambers were used to simulate a misaligned chamber relative to the bore axis. Precision and accuracy tests were then performed at 200 m in an indoor range under controlled conditions. For this project, 5.56 mm CT ammunition was used. As the chamber axis offset relative to the gun bore was increased, the mean point of impact was displaced away from the target center. The shift in the impact location is explained by the presence of in-bore yaw which results in lateral throw-off and aerodynamic jump components. The linear theory of ballistics is used to establish a relationship between the chamber misalignment and the resulting projectile mean point of impact for a rifle developed to fire CT ammunition. This relationship allows for the prediction of the mean point of impact given a chamber misalignment. 展开更多
关键词 精度测试 弹药箱 CT 失调 控制条件 空气动力 线性理论 孔轴线
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Bayesian inference for ammunition demand based on Gompertz distribution 被引量:4
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作者 ZHAO Rudong SHI Xianming +2 位作者 WANG Qian SU Xiaobo SONG Xing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第3期567-577,共11页
Aiming at the problem that the consumption data of new ammunition is less and the demand is difficult to predict,combined with the law of ammunition consumption under different damage grades,a Bayesian inference metho... Aiming at the problem that the consumption data of new ammunition is less and the demand is difficult to predict,combined with the law of ammunition consumption under different damage grades,a Bayesian inference method for ammunition demand based on Gompertz distribution is proposed.The Bayesian inference model based on Gompertz distribution is constructed,and the system contribution degree is introduced to determine the weight of the multi-source information.In the case where the prior distribution is known and the distribution of the field data is unknown,the consistency test is performed on the prior information,and the consistency test problem is transformed into the goodness of the fit test problem.Then the Bayesian inference is solved by the Markov chain-Monte Carlo(MCMC)method,and the ammunition demand under different damage grades is gained.The example verifies the accuracy of this method and solves the problem of ammunition demand prediction in the case of insufficient samples. 展开更多
关键词 ammunition demand prediction Bayesian inference Gompertz distribution system contribution Markov chain-Monte Carlo(MCMC)method
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Paleoenvironments Recorded in a New-Type Ferromanganese Crust fromthe East Philippine Sea 被引量:1
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作者 徐兆凯 李安春 +1 位作者 蒋富清 李铁刚 《Journal of China University of Geosciences》 SCIE CSCD 2006年第1期34-42,共9页
We attempt to recover the paleocnvironments recorded in the accretion of a typical newtype hydrogenetic ferromanganese crust from the deep water areas of the East Philippine Sea. From detailed geochemical and U-series... We attempt to recover the paleocnvironments recorded in the accretion of a typical newtype hydrogenetic ferromanganese crust from the deep water areas of the East Philippine Sea. From detailed geochemical and U-series chronological studies, analysis of major and minor elements performed by X-ray fluorescence spectrometry (XRF) and inductively coupled plasma-mass spectrometer (ICPMS), three major accretion periods and corresponding paleocnvironments can be ascertained. The first period is a faster accretion period in the terminal Late Miocene to the Early Pliocene with looser structure and higher volcanic detritus content, corresponding to the active Antarctic bottom waters and depressed temperature from the intermediate Middle Miocene to the Early Pliocene. The second period is a pulse of pelagic clay deposition at the Early to Middle Pliocene, reflecting the shrinkage of the Antarctic bottom waters and the global temperature elevation of this period. The third period is a slower accretion period from the Middle Pliocene, which indicates the more violent activity of Antarctic bottom waters once again and more depressed temperature than the first period, facilitating the accretion of a more compact and pure ferromanganese zone. The paleoceanographic histories of these studied areas had not been made clear in previous research. 展开更多
关键词 new-type ferromanganese crust PALEOENVIRONMENT GEOCHEMISTRY East Philippine Sea
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Cultivating New-type Farmers Based on the Theory of Human Resources Development 被引量:3
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作者 ZHANG Li 《Asian Agricultural Research》 2010年第7期14-18,共5页
Under the direction of theory of human resources development,this thesis analyzes the impact of rural human resources development oncultivating new-type farmers.Firstly,it increases the input of rural basic education;... Under the direction of theory of human resources development,this thesis analyzes the impact of rural human resources development oncultivating new-type farmers.Firstly,it increases the input of rural basic education;secondly,it reinforces the vocational education and technologytraining;thirdly,it promotes the rural medical and public health services;fourthly,it quickens the rural labor transfer.The status quo of China's ruralhuman resources has been analyzed as follows:in terms of the quantity of rural human resources,the status quo is large and quick-developed baseof rural human resources,high labor participatory rate,and constitution of low age;in terms of the quality of rural human resources,the status quois the ubiquitous low quality of rural human resources,low technological level of rural human resources,and overall low physical quality of farmers;in terms of the structure of rural human resources,the status quo is the irrational industrial structure distribution and imbalanced regional structuredistribution.The thesis also discusses the edification of theory of human resources development in cultivating new-type farmers.First,in terms ofthe control over quantity of rural human resources,it is to keep the stability of family planning policy,and expedite the transfer of rural surplus la-bor;second,in terms of promoting the quality of rural human resources,it is to bolster the development of reserve rural labor force resources,toconstruct the adult educational training system with Chinese characteristics,and to build rural primary health care system;third,in terms of adjus-ting the structure of rural human resources,it is to perfect rural human resources market,and adjust rural economical structure and talents struc-ture. 展开更多
关键词 Development of human resources new-type farmers Educational training Rural surplus labor force China
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BUILDING A MODERATELY PROSPEROUS SOCIETY IN ALL RESPECTS——New-Type Industrialization 被引量:3
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作者 Zhang Qizi 《China Economist》 2020年第1期48-71,共24页
After announcing the goal of building a moderately prosperous society in all respects by 2020, the Chinese leadership also called for a new path of industrialization, putting a premium on quality and new development c... After announcing the goal of building a moderately prosperous society in all respects by 2020, the Chinese leadership also called for a new path of industrialization, putting a premium on quality and new development concepts. Unlike traditional industrialization in the broad or narrow sense, new-type industrialization features synergy between primary, secondary, and tertiary industries, integration between traditional economy and the new economy, environmental protection, technology progress, and innovation. It represents an inclusive approach to industrial development. At the fundamental level, the success of China’s new-type industrialization can be attributed to China’s inclusive learning and innovations. 展开更多
关键词 building a moderately prosperous society new-type industrialization inclusive learning and innovation
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Resistance characteristics of the ball packed-bed regenerator of the new-type swirl flow hot blast stove 被引量:1
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作者 Hongzhi Guo, Xiaohu Cheng, and Shuchen ZhangDepartment of Thermal Engineering, University of Science and Technology Beijing, Beijing 100083, China 《Journal of University of Science and Technology Beijing》 CSCD 2003年第1期21-24,共4页
A renovation project of miniaturization and high efficiency is provided for the hot blast stove .The experimental data tested feasibility of the new-type swirl flow hot blast stove. The normal and hot state experiment... A renovation project of miniaturization and high efficiency is provided for the hot blast stove .The experimental data tested feasibility of the new-type swirl flow hot blast stove. The normal and hot state experiments have been done through changing the angle of gas entering into the regenerator. Factors influencing pressure drop have been studied and analyzed. The experimental results can be formulated in the form of the Ergun equation. The regression equation is obtained. And two modified coefficients are offered to the regenerator pressure drop of the new-type swirl flow hot blast stove. 展开更多
关键词 the new-type swirl flow hot blast stove REGENERATOR regression equation resistance drop
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Characteristic Town: The Effective Path of New-type Urbanization with Chinese Characteristics Based on the Investigation of Intemet Town Wuzheng, Aficion Chocolate Town Jiashan, Photovoltaic Town Xiuzhou in Zhejiang 被引量:1
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作者 WU Zhen-ping 《Journal of Literature and Art Studies》 2018年第3期412-416,共5页
The characteristic town is a dynamic and vivid case of experience of Zhejiang. With the internet town Wuzheng, Aficion chocolate town Jiashan, photovoltaic town Xiuzhou in Zhejiang as the research perspective, the con... The characteristic town is a dynamic and vivid case of experience of Zhejiang. With the internet town Wuzheng, Aficion chocolate town Jiashan, photovoltaic town Xiuzhou in Zhejiang as the research perspective, the concept of development that the production, life and ecology merge together and the development direction and value of New-type urbanization is consistent, and it is the effective path of New-type urbanization development. At the same time, these towns provide a model for the development of the country small town 展开更多
关键词 haracteristic town new-type urbanization the production life and ecology merge together
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Dynamic changes and driving factors of land use under new-type urbanization: A case of Guiyang 被引量:1
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作者 ZENG Fang WEI Yuan 《Ecological Economy》 2015年第3期236-242,共7页
With the continuous progress of new-type urbanization in Karst mountain area, how to correctly deal with the relationship between urban economy and land use are attracting much attention. Based on the land-use change ... With the continuous progress of new-type urbanization in Karst mountain area, how to correctly deal with the relationship between urban economy and land use are attracting much attention. Based on the land-use change data, this paper analyzes the characteristics of land use change and its driving factors in Guiyang with the method of land-use dynamic analysis, land utilization and factor correlation analysis. We get the following results:(1) the change of land use was obvious during 2004 and 2012. The area of arable land and other land were decreased, the rate of decrease are 3.89% and 8.24%. In the meantime, a series of construction land and forest area increased a lot, the rate of increase are 3.89% and 8.24%.(2) The integrated land use dynamic degree of two research stages(2004-2009 and 2009-2012) were decreased from 2.12% to 0.34%, this suggests dynamic changes of land tend to be stable.(3) Four kinds of Land use class have a great contribution to the index of land use degree respectively. The composite index of land use degree rose from 229.58 to 247.19 during 2004 and 2012; the land use is still in the development stage.(4) Economy, population, transportation and policy guidance are the main drivers of land use change. 展开更多
关键词 new-type URBANIZATION LAND USE driving FACTORS GUI
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Study on Stable Scanning of Terminal Sensing Ammunition Based on Quaternion Transformation
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作者 李臣明 刘怡昕 《Defence Technology(防务技术)》 SCIE EI CAS 2012年第1期11-15,共5页
Euler angles and Euler kinematics equation of terminal sensing ammunition are expressed and rewritten by using quaternion to solve the singular problem in using Euler angles to describe the motion.The contrastive simu... Euler angles and Euler kinematics equation of terminal sensing ammunition are expressed and rewritten by using quaternion to solve the singular problem in using Euler angles to describe the motion.The contrastive simulations are performed in order to validate the correctness and advantage of the quaternion description.The simulation results show that the dynamic model with quaternion have stable solution,there is not singular point in the calculation,and the ballistic model rewritten by using the quaternion is suitable for describing the terminal sensing ammunition's scanning motion than the common Euler equation. 展开更多
关键词 basic mechaincs foundation mechanics BALLISTICS terminal sensing ammunition singular point QUATERNION
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Design of Guided Air Ammunition's Optimal Guidance Law
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作者 刘敏 刘藻珍 王保成 《Journal of Beijing Institute of Technology》 EI CAS 2005年第4期396-399,共4页
Some long distance air ammunition can be used to attack large still target. According to this character and according to the mathematical description of target-missile relative motion built by the message supplied by ... Some long distance air ammunition can be used to attack large still target. According to this character and according to the mathematical description of target-missile relative motion built by the message supplied by the strapdown inertial navigation system/global position system (SINS/GPS) of air ammunition, optimal guidance law is designed by applying optimal control theory. The simulation is provided to indicate that when the air ammunition reaches the target, its line-of-sight (LOS) and LOS angular rate can nearly equal zero. So the air ammunition can get good terminal attitude, and the air ammunition reaches the target at the expected velocity and heading. 展开更多
关键词 air ammunition guidance law optimal control
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Design of MEMS C-Band Microstrip Antenna Array Based on High-Resistance Silicon for Intelligent Ammunition
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作者 Xue Zhao Xiao-Ming Liu 《Journal of Electronic Science and Technology》 CAS 2013年第1期101-105,共5页
In recent years, microstrip antennas have been more widely applied in satellite communications, mobile phones, unmanned aerial vehicle (UAV), and weapons. A micro-electro-mechanical systems-based (MEMS-based) high... In recent years, microstrip antennas have been more widely applied in satellite communications, mobile phones, unmanned aerial vehicle (UAV), and weapons. A micro-electro-mechanical systems-based (MEMS-based) high-resistance silicon C-band microstrip antenna array has been designed for the intelligent ammunition. The center frequency is 4.5 GHz. A cavity has been designed in substrate to reduce the dielectric constant of silicon and high-resistance silicon has been used as the material of substrate to improve the gain of antenna. It is very easy to be manufactured by using MEMS technology because of the improved structure of the antenna. The results show that the gain of the antenna is 8 dB and voltage standing wave ratio (VSWR) is less than 2 by the analysis and simulation in high freauencv structure simulator (HFSS). 展开更多
关键词 C-BAND high frequency structure simulator high-resistance silicon intelligent ammunition microstrip antenna array.
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