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Beamforming Design for IRS-and-UAV-Aided Two-Way Amplify-and-Forward Relay Networks in Maritime IoT
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作者 Wang Xuehui Shu Feng +6 位作者 Wu Yuanyuan Shi Weiping Yan Shihao Zhao Yifan Cheng Qiankun Sun Zhongwen Wang Jiangzhou 《China Communications》 SCIE CSCD 2024年第8期45-61,共17页
In this paper,an intelligent reflecting surface(IRS)-and-unmanned aerial vehicle(UAV)-assisted two-way amplify-and-forward(AF)relay network in maritime Internet of Things(IoT)is proposed,where ship1(S1)and ship2(S2)ca... In this paper,an intelligent reflecting surface(IRS)-and-unmanned aerial vehicle(UAV)-assisted two-way amplify-and-forward(AF)relay network in maritime Internet of Things(IoT)is proposed,where ship1(S1)and ship2(S2)can be viewed as data collecting centers.To enhance the message exchange rate between S1 and S2,a problem of maximizing minimum rate is cast,where the variables,namely AF relay beamforming matrix and IRS phase shifts of two time slots,need to be optimized.To achieve a maximum rate,a low-complexity alternately iterative(AI)scheme based on zero forcing and successive convex approximation(LC-ZF-SCA)algorithm is presented.To obtain a significant rate enhancement,a high-performance AI method based on one step,semidefinite programming and penalty SCA(ONSSDP-PSCA)is proposed.Simulation results show that by the proposed LC-ZF-SCA and ONS-SDP-PSCA methods,the rate of the IRS-and-UAV-assisted AF relay network surpass those of with random phase and only AF relay networks.Moreover,ONS-SDP-PSCA perform better than LC-ZF-SCA in aspect of rate. 展开更多
关键词 BEAMFORMING maritime Internet of Things phase shift rate performance two-way amplify-and-forward relay unmanned aerial vehicle
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Research on the Ideological Politics Education of College Students from the Perspective of New Media 被引量:1
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作者 Kaiwen Zhu 《Journal of Contemporary Educational Research》 2020年第2期68-72,共5页
With the continuous development of the economy and society,new media technologies have been widely used in every industry and all walks of life.New media technologies are also applied in the ideological politics educa... With the continuous development of the economy and society,new media technologies have been widely used in every industry and all walks of life.New media technologies are also applied in the ideological politics education of the Chinese college students.Therefore,this article makes a brief analysis of college education in the context of the new media technology.New media technology is applied to the ideological politics education of college students,which not only places the emphasis on the importance of ideological politics in an intuitive manner towards the students,but also creates a good social atmosphere and innovates the ideological and moral education model. 展开更多
关键词 New MEDIA HORIZON COLLEGE STUDENTS Ideological POLITICS Education PATH
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Strategies for College English Teaching in Military Academies
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作者 WANG Zi-yan 《海外英语》 2015年第4期128-129,共2页
As pointed out in College English Curriculum Requirements, the main objective of College English teaching and learning in military academies is to"develop cadets' ability to use English in a well-rounded way,... As pointed out in College English Curriculum Requirements, the main objective of College English teaching and learning in military academies is to"develop cadets' ability to use English in a well-rounded way, especially in their listening and speaking abilities, so that in their future studies and careers they will be able to communicate effectively, and at the same time enhance their ability to study independently and improve their comprehensive cultural quality so as to meet the needs of PLA's modernization."This paper focuses on some effective strategies which may be of some practical use for the teaching and learning of the English language. 展开更多
关键词 STRATEGIES COLLEGE English TEACHING MILITARY ACADEMIES
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Group-Based Successive Interference Cancellation for Multi-Antenna NOMA System with Error Propagation 被引量:1
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作者 Cheng Hu Hong Wang +1 位作者 Changxiang Li Rongfang Song 《China Communications》 SCIE CSCD 2023年第8期276-287,共12页
Non-orthogonal multiple access(NOMA)is viewed as a key technique to improve the spectrum efficiency and solve the issue of massive connectivity.However,for power domain NOMA,the required overall transmit power should ... Non-orthogonal multiple access(NOMA)is viewed as a key technique to improve the spectrum efficiency and solve the issue of massive connectivity.However,for power domain NOMA,the required overall transmit power should be increased rapidly with the increasing number of users in order to ensure that the signal-to-interference-plus-noise ratio reaches a predefined threshold.In addition,since the successive interference cancellation(SIC)is adopted,the error propagation would become more serious as the order of SIC increases.Aiming at minimizing the total transmit power and satisfying each user’s service requirement,this paper proposes a novel framework with group-based SIC for the deep integration between power domain NOMA and multi-antenna technology.Based on the proposed framework,a joint optimization of power control and equalizer design is investigated to minimize transmit power consumption for uplink multi-antenna NOMA system with error propagations.Based on the relationship between the equalizer and the transmit power coefficients,the original problem is transformed to a transmit power optimization problem,which is further addressed by a parallel iteration algorithm.It is shown by simulations that,in terms of the total power consumption,the proposed scheme outperforms the conventional OMA and the existing cluster-based NOMA schemes. 展开更多
关键词 multi-antenna NOMA group-based successive interference cancellation error propagation power control
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From De-collectivization to Re-collectivization: New Transformation Trend in Agriculture Production in Taicang City of the Eastern China from the Perspective of ‘Governmentality’
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作者 CHEN Cheng GAO Jinlong +2 位作者 CAO Hui CHEN Jianglong CHEN Feiyu 《Chinese Geographical Science》 SCIE CSCD 2023年第3期531-548,共18页
The continuous development of agricultural technologies and produces trade and updated state reforms strongly shape the dominant organizing styles of local agriculture production.Since the end of the 1970s,rural China... The continuous development of agricultural technologies and produces trade and updated state reforms strongly shape the dominant organizing styles of local agriculture production.Since the end of the 1970s,rural China has witnessed a drastic agriculture transformation featured by de-collectivization,and recently in Taicang,a developed city in the eastern China,a kind of new cooperative farms have replaced the smallholders by pooling households’contracted farmland,signaling a new shift tendency towards agriculture recollectivization that is distinctive compared to other countries.Given the state governance’s leadership in promoting this latest transformation,drawing on the theoretical concept of‘governmentality’that is powerful in understanding how to govern the society to meet certain objectives,this paper examines the accurate processes of agriculture re-collectivization in Taicang City based on the methods of semi-structured interview and participant observation.Our research shows that the China’s tax-sharing and relevant reforms in the 1990s framed a new governance structure in line with the new mode of‘governmentality’closely linked to‘advanced liberalism’,creating the responsibility shift from central to local governments and a set of evaluation technologies,and guiding various actors to engage in the agriculture re-collectivization practice in Taicang.Importantly,the considerable subsidies and the impressive extension services in terms of farming personnel training and agricultural techniques diffusion underpin the normal running of cooperative farms and contribute to the local implementation of national strategy of agriculture modernization.We argue that the combination of distinctive institutional arrangement of rural land owned by village collectives in China and the burgeoning local economy allows the developed areas to re-collectivizing the agriculture production for ensuring grain self-sufficiency rather than capturing more share in global agriculture products trade,and that the cooperative farms in our case have been deeply integrated into the‘modern procurement system’and become more sensitive to market fluctuation,requiring rural extension service to transform towards farms’capacity building for maintaining the longterm development momentum. 展开更多
关键词 EASTERN TRANSFORMATION COLLECTIVE
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A Mixed Method for Feature Extraction Based on Resonance Filtering
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作者 Xia Zhang Wei Lu +2 位作者 Youwei Ding Yihua Song Jinyue Xia 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3141-3154,共14页
Machine learning tasks such as image classification need to select the features that can describe the image well.The image has individual features and common features,and they are interdependent.If only the individual ... Machine learning tasks such as image classification need to select the features that can describe the image well.The image has individual features and common features,and they are interdependent.If only the individual features of the image are emphasized,the neural network is prone to overfitting.If only the common features of images are emphasized,neural networks will not be able to adapt to diversified learning environments.In order to better integrate individual features and common features,based on skeleton and edge individual features extraction,this paper designed a mixed feature extraction method based on reso-nancefiltering,named resonance layer.Resonance layer is in front of the neural network input layer,using K3M algorithm to extract image skeleton,using the Canny algorithm to extract image border,using resonancefiltering to reconstruct training image byfiltering image noise,through the common features of the images in the training set and efficient expression of individual characteristics to improve the efficiency of feature extraction of neural network,so as to improve the accuracy of neural network prediction.Taking the fully connected neural net-work and LeNet-5 neural networks for example,the experiment on handwritten digits database shows that the proposed mixed feature extraction method can improve the accuracy of training whilefiltering out part of image noise data. 展开更多
关键词 Deep learning feature extraction resonancefiltering image reconstruction
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Research on the Application of Reinforcement Learning Model in Vocational Education System
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作者 Fei Xue 《Journal on Artificial Intelligence》 2023年第1期131-143,共13页
Vocational education can effectively improve the vocational skills of employees,improve people’s traditional concept of vocational education,and focus on the training of vocational skills for students by using new ed... Vocational education can effectively improve the vocational skills of employees,improve people’s traditional concept of vocational education,and focus on the training of vocational skills for students by using new educational methods and concepts,so that they can master key vocational skills and develop key abilities.In this paper,three different learning models,Deep Knowledge Tracing(DKT),Dynamic Key-Value Memory Networks(DKVMN)and Double Deep Q-network(DDQN),are used to evaluate the indicators in the vocational education system.On the one hand,the influence of learning degree on the performance of the model is compared,on the other hand,the performance evaluation of three models under the same learning effect is compared,so as to obtain the best learning model applied to the field of skill training.In order to accurately evaluate the learning status of students,the loss function curves under three models are compared.Finally,the error rate of students in vocational skills education tends to be zero,and the learning process of intensive learning effectively improves students’mastery of skills and key abilities. 展开更多
关键词 Vocational education intensive learning key abilities
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Contrast and Fusion: The Role of Regional Culture in Shaping Jiangsu Paper-Cut Art
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作者 Yan Gu 《Journal of Contemporary Educational Research》 2023年第6期64-77,共14页
The Chinese paper-cut art,first recorded in the Wei,Jin,and Southern and Northern Dynasties(220 AD-589 AD),has witnessed the changes of times,yet it still retains its artistic vitality.Chinese papercuts can be divided... The Chinese paper-cut art,first recorded in the Wei,Jin,and Southern and Northern Dynasties(220 AD-589 AD),has witnessed the changes of times,yet it still retains its artistic vitality.Chinese papercuts can be divided into two schools:the northern and the southern.Jiangsu,located in the region of the Yellow River and Huai River,is the geographical dividing line between those two schools.Therefore,in Jiangsu Province,not only the rough northern art form(such as in Xuzhou papercut)but also the graceful southern art form(such as in Jintan papercut)is evident.In addition,the unique combined paper-cut style(such as in Yangzhou and Nanjing papercuts)can be appreciated here.Although several scholars have analyzed the artistic characteristics of Jiangsu papercut based on cultural background,very few have discussed the differences between the northern and the southern in terms of content,connotation,and style.Through literature review and collected works made by local craftsmen and inheritors of this tradition,this article aims to show readers the contrast and integration of papercuts in these four places under the influence of different cultural and economic backgrounds in order to better understand the role of regional factors in shaping the art form of papercuts in Jiangsu Province.Nowadays,with the change in people’s lifestyles,the living space of traditional papercuts has shrunk drastically,and its practicability in the past has faded.Instead,people are searching for and creating cultural and artistic value in museums,tourist attractions,and commodity transactions.Among them,some works have deviated from the cultural background of traditional paper-cut art.Therefore,this paper provides a basis for the current development of this art form in Jiangsu. 展开更多
关键词 Chinese papercuts Jiangsu papercut Regional cultural background Comparison INTEGRATION
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Study on Action of Acupuncture on Ventromedial Nucleus of Hypothalamus in Obese Rats 被引量:10
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作者 刘志诚 孙凤岷 +7 位作者 苏静 赵玫 朱苗花 王沂争 魏群利 李嘉 顾云 王友京 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2001年第3期220-224,共5页
Effects of acupuncture on the spontaneous discharge of nerve cells and levels of monoamine neurotransmitters in ventromedial nucleus of hypothalamus (VMH) of the obese rats were investigated. Results indicated that th... Effects of acupuncture on the spontaneous discharge of nerve cells and levels of monoamine neurotransmitters in ventromedial nucleus of hypothalamus (VMH) of the obese rats were investigated. Results indicated that the levels of tyrosine (Tyr) and dopamine (DA) were lowered, the levels of 5-hydroxytryptamine (5-HT) and 5-hydoxyindole acetic acid (5-HIAA) increased, and the frequency of the spontaneous discharge of nerve cells in VMH lowered in the obese rat group as compared with the normal group. When acupuncture obtained the effect of weight reduction, the frequency of spontaneous discharges of nerve cells in VMH were markedly increased, and the levels of Tyr, DA and tryptamine (Typ) and 5-HT/5-HIAA ratio elevated, and the 5-HT level lowered. It is suggested that the virtuous regulative action of acupuncture on VMH might be one of the key factors in acupuncture for weight reduction. 展开更多
关键词 ACUPUNCTURE Animals Dopamine HYPOTHALAMUS Male Obesity Random Allocation RATS Rats Sprague-Dawley SEROTONIN TYROSINE Ventromedial Hypothalamic Nucleus
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Leakage Prediction Method for Contacting Mechanical Seals with Parallel Faces 被引量:17
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作者 SUN Jianjun WEI Long +1 位作者 FENG Xiu GU Boqin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第1期7-15,共9页
Since the beginning of the 20th century, many researches on the sealing characteristic of mechanical seals were carried out broadly and in depth by various methods and some leakage models were built. But due to the la... Since the beginning of the 20th century, many researches on the sealing characteristic of mechanical seals were carried out broadly and in depth by various methods and some leakage models were built. But due to the lack of the way to characterize the main factors of influence on the leakage, most of the early researches were based on the assumptions that the seal faces topography and the frictional conditions were invariant. In the early built models, the effect of the surface topography change of the seal face on the leakage rate was neglected. Based on the fractal theory, the contact of end faces of the rotary and stationary rings was simplified to be the contact of a rough surface and an ideal rigid smooth surface, and the contact interface's cavity size-distribution function as well as the fractal characteristic of the cavity profile curve was discussed. By analyzing the influence of abrasion on the seal face topography and the leakage channel, the time-correlation leakage prediction model of mechanical seals based on the fractal theory was established and the method for predicting the leakage rate of mechanical seals with parallel plane was proposed. The values of the leakage rate predicted theoretically are similar to the measured values of the leakage rate in the model test and in situ test. The experimental results indicate that the leakage rate of mechanical seals is a transient value. The surface topography of the end faces of the seal tings and its change during the frictional wear of mechanical seals can be accurately characterized by the fractal parameters. Under the work conditions of changeless frictional mechanism, the fractal parameters measured or calculated based on the accelerated testing equation can be used to predict the leakage rate of mechanical seal in service. The proposed research provides the basis for determining the leakage state and predicting working life of mechanical seal. 展开更多
关键词 mechanical seal leakage rate fractal theory frictional wear accelerated test model
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The Fouling Mechanism of Ceramic Membranes Used for Recovering TS-1 Catalysts 被引量:8
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作者 仲兆祥 李冬燕 +2 位作者 刘馨 邢卫红 徐南平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第1期53-57,共5页
Ceramic ultrafiltration membranes were used to separate titanium silicalite-1 (TS-1) catalysts from the slurry of catalytic ammoximation of cyclohexanone to oxime. Silica was shown to have a great effect on membrane... Ceramic ultrafiltration membranes were used to separate titanium silicalite-1 (TS-1) catalysts from the slurry of catalytic ammoximation of cyclohexanone to oxime. Silica was shown to have a great effect on membrane fouling in the alkaline environment of this system. In the ammoximation system, there are three main silica sources, which are residual silica on the catalyst particles surface during preparation, silica dissolved from TS-1 catalyst particles by ammonia solvent, and silica sol added into the reaction slurry to inhibit the dissolution erosion of the TS-1 catalyst. The silica dissolved by ammonia has been proved to influence membrane fouling most among the three silica sources. This was because the amount of silica dissolved by ammonia was the largest, and the polymerization of silica monomers at high concentration caused colloid particles formation, which led to a dense cake layer depositing on the membrane surface. Meanwhile, the size reduction of catalyst particles caused by alkaline dissolution also increased specific resistances of cake layers. 展开更多
关键词 TS-1 catalyst ceramic membrane membrane fouling
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Orbital Milling Hole of Aerospace Al-Alloy with Big Pitch 被引量:4
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作者 单以才 何宁 +2 位作者 李亮 赵威 秦晓杰 《Transactions of Tianjin University》 EI CAS 2011年第5期329-335,共7页
To improve the processing efficiency and the quality of orbital milling hole of aerospace Al-alloy, the big-pitch influence on cutting force and hole quality was studied experimentally. First, a program based on horiz... To improve the processing efficiency and the quality of orbital milling hole of aerospace Al-alloy, the big-pitch influence on cutting force and hole quality was studied experimentally. First, a program based on horizontal lathe was proposed based on kinematics analysis of orbital milling. Then, the cutting force at different stages and the hole quality with different pitches were measured. Results show that the axial force and radial force increase with the pitch amplification during orbital milling. However, the axial force in the orbital milling hole is about 8—10 times smaller than that in the conventional drilling. The diameter error of milling hole is 48—93 μm, and the surface roughness of milling hole is 1.2—1.7 μm. Finally, an orbital milling device with big pitch was designed. 展开更多
关键词 aerospace Al-alloy orbital milling hole cutting force quality orbital milling device
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Study of dual-directional high rate secure communication systems using chaotic multiple-quantum-well lasers 被引量:4
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作者 颜森林 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第11期3271-3278,共8页
A scheme of synchronized injection multi-quantum-well (MQW) laser system using optical couphng-feedback is presented for performing chaotic dual-directional secure communication. The performance characterization of ... A scheme of synchronized injection multi-quantum-well (MQW) laser system using optical couphng-feedback is presented for performing chaotic dual-directional secure communication. The performance characterization of chaos masking is investigated theoretically, the equation of synchronization demodulation is deduced and its root is also given. Chaos masking encoding with a rate of 5 Gbit/s and a modulation frequency of 1 GHz, chaos modulation with a rate of 0.2 Gbit/s and a modulation frequency of 0.2 GHz and chaos shifting key with a rate of 0.2 Gbit/s are numerically simulated, separately. The ratio of the signal to the absolute synchronous error and the time for achieving synchronous demodulation are analysed in detail. The results illustrate that the system has stronger privacy and good performances so that it can be applied in chaotic dual-directional high rate secure communications. 展开更多
关键词 CHAOS MQW laser SECURE dual-directional communication
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TREATMENT OF ACUTE ABDOMEN BY ELECTRO-ACUPUNCTURE——A Report of 245 Cases 被引量:2
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作者 顾月华 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1992年第2期110-113,共4页
Acute abdomen is an emergency diseasecommonly seen in clinic.It can be caused bymany diseases and is characterized by ab-rupt onset,acute abdominal pain and evenshock in severe cases.Since 1977,I haveused electro-acup... Acute abdomen is an emergency diseasecommonly seen in clinic.It can be caused bymany diseases and is characterized by ab-rupt onset,acute abdominal pain and evenshock in severe cases.Since 1977,I haveused electro-acupuncture to treat this dis-ease and made a summary of 164 cases 展开更多
关键词 acupuncture CLINIC BILATERAL minutes ABDOMEN MOXIBUSTION stimulation STIMULATOR needle emergency
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AIDS-Related Knowledge, Attitudes and Behavior Survey among the “Migrant” Population in China 被引量:5
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作者 Jian-fang ZHOU Xiao-ming SUN +2 位作者 Jonanne Mantell Xiao-mei RU Yong WEN 《Journal of Reproduction and Contraception》 CAS 2007年第2期155-162,共8页
Objective To realize AIDS related knowledge, attitude and behavior among floating people in China and discuss its influencial factors, and to provide the evidence for how to prevent AIDS in floating population. Method... Objective To realize AIDS related knowledge, attitude and behavior among floating people in China and discuss its influencial factors, and to provide the evidence for how to prevent AIDS in floating population. Methods The data were collected from the "Sex and Reproductive Health Baseline Survey among Floating People in China" conducted in March 2004. The standard questionnaires were used to interview altogether 4 900 floating people from 6 provinces. Results Nearly 95.4 % of them had heard about AIDS, but only 0.5% can judge all the transmitted ways and no-transmitted ways correctly, 45.9 % believed that we need to isolate the HIV positive people. Only 65.7% knew that using condom can preventive HIV infection, 43. 7% showed their understanding about the man who has long time no sexual life has sex with a sexual worker. About 13.6% floating people chose condom as FP method and among them only 34. 6% used condom every time. Conclusion Chinese floating people are lack of AIDS knowledge. Most of them do not practise Safe Sex Activity. We need to give more intervention to the floating population. 展开更多
关键词 floating population AIDS related kanowledge ATTITUDE BEHAVIOR
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A Method for Retrieving Water-leaving Radiance from Landsat TM Image in Taihu Lake, East China 被引量:3
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作者 WANG Deyu FENG Xuezhi +1 位作者 MA Ronghua KANG Guoding 《Chinese Geographical Science》 SCIE CSCD 2007年第4期364-369,共6页
The visible and infrared bands of Landsat Thematic Mapper (TM) can be used for inland water studies. A method of retrieving water-leaving radiance from TM image over Taihu Lake in Jiangsu Province of China was inves... The visible and infrared bands of Landsat Thematic Mapper (TM) can be used for inland water studies. A method of retrieving water-leaving radiance from TM image over Taihu Lake in Jiangsu Province of China was investigated in this article. To estimate water-leaving radiance, atmospheric correction was performed in three visible bands of 485nm, 560nm and 660rim. Rayleigh scattering was computed precisely, and the aerosol contribution was estimated by adopting the clear-water-pixels approach. The clear waters were identified by using the Landsat TM middle-infrared band (2.1 μm), and the water-leaving radiance of clear water pixels in the green band was estimated by using field data. Aerosol scattering at green band was derived for six points, and interpolated to match the TM image. Assuming the atmospheric correction coefficient was 1.0, the aerosol scattering image at blue and red bands were derived. Based on a simplified atmospheric radiation transfer model, the water-leaving radiance for three visible bands was retrieved. The water-leaving radiance was normalized to make it comparable with that estimated from other remotely sensed data acquired at different times, and under different atmospheric conditions. Additionally, remotely sensed reflectance of water was computed. To evaluate the atmospheric correction method presented in this article, the correlation was analyzed between the corrected remotely sensed data and the measured water parameters based on the retrieval model. The results show that the atmospheric correction method based on the image itself is more effective for the retrieval of water parameters from Landsat TM data than 6S (Second Simulation of the Satellite Signal in the Solar Spectrum) code based on standard atmospheric and aerosol models. 展开更多
关键词 retrieval method water-leaving radiance Landsat TM image Taihu Lake
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New Approach to Cluster Synchronization in Complex Dynamical Networks 被引量:3
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作者 LU Xin-Biao QIN Bu-Zhi LU Xin-Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第3期485-489,共5页
In this paper, a distributed control strategy is proposed to make a complex dynamical network achieve cluster synchronization, which means that nodes in the same group achieve the same synchronization state, while nod... In this paper, a distributed control strategy is proposed to make a complex dynamical network achieve cluster synchronization, which means that nodes in the same group achieve the same synchronization state, while nodes in different groups achieve different synchronization states. The local and global stability of the cluster synchronization state are analyzed. Moreover, simulation results verify the effectiveness of the new approach. 展开更多
关键词 cluster synchronization complex network distributed control strategy
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Controlling Chaos in a Semiconductor Laser via Weak Optical Positive Feedback and Modulating Amplitude 被引量:2
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作者 YAN Sen-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期491-494,共4页
Numerical analysis of weak optical positive feedback (OPF) controlling chaos is studied in a semiconductor laser. The physical model of controlling chaos produced via modulating the current of semiconductor laser is... Numerical analysis of weak optical positive feedback (OPF) controlling chaos is studied in a semiconductor laser. The physical model of controlling chaos produced via modulating the current of semiconductor laser is presented under the condition of OPF. We find the physical mechanism that the nonlinear gain coefficient and linewidth enhance- ment factor of the laser are affected by OPF so that the dynamical behaviour of the system can be efficiently controlled. Chaos is controlled into a single-periodic state, a dual-periodic state, a tri-periodic state, a quadr-periodic state, a pentaperiodic state, and the laser emitting powers are increased by OPF in simulations. Lastly, another chaos-control method with modulating the amplitude of the feedback light is presented and numerically simulated to control chaotic laser into multi-periodic states. 展开更多
关键词 CHAOS control positive feedback PERIOD
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Impact of Sediment Supply on Spartina Salt Marshes 被引量:5
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作者 SHEN Yong-Ming YANG Jing-Song +3 位作者 WANG Yan-Hong FENG Nian-Hua ZHOU Qin ZENG Hua 《Pedosphere》 SCIE CAS CSCD 2008年第5期593-598,共6页
During the past century,natural and human modifications of environmental systems have greatly accelerated coastal salt marsh deterioration and shoreline retreat in many regions worldwide. Field investigation,profile a... During the past century,natural and human modifications of environmental systems have greatly accelerated coastal salt marsh deterioration and shoreline retreat in many regions worldwide. Field investigation,profile analysis,geographical information analysis,and remote sensing were employed in combination to study the effect of sediment on Spartina alterniflora salt marshes of the coast in Jiangsu Province,East China. The results indicated that the propagation of Spartina alterniflora salt marshes was closely related to regional sediment conditions,especially the supply of fine-grained materials. Additionally,because of the dense and high grass in Spartina alterniflora salt marshes,wave energy and tidal currents were baffled and weaker than those of the adjacent,unvegetated mud flats. Fine sediment was hardly resuspended under the low energy conditions in the Spartina alterniflora salt marshes. 展开更多
关键词 COST salt marsh sediment supply Spartina alterniflora tidal mud flat
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PROPHYLACTIC AND THERAPEUTIC EFFECTS OF ACUPUNCTURE ON SIMPLE OBESITY COMPLICATED BY CARDIOVASCULAR DISEASES 被引量:1
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作者 刘志诚 孙凤岷 +4 位作者 李嘉 施小波 胡丽梅 王沂争 钱真良 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1992年第1期21-29,共9页
In order to understand the prophylactic-therapeutic effects of acupuncture and moxibustion insimple obesity complicated by cardiovascular diseases,we have observed in 102 cases the changesof pathogenetic and hazardous... In order to understand the prophylactic-therapeutic effects of acupuncture and moxibustion insimple obesity complicated by cardiovascular diseases,we have observed in 102 cases the changesof pathogenetic and hazardous factors and the regulating function of vegetative nerves oncardiovascular activities.The results showed that the therapeutic effect of acupuncture andmoxibustion was good with a total effective rate of 88.24%.At the same time,acupuncture andmoxibustion were found to have a benign conversion effect on the loin hip ratio(the pathogeneticfactor),the arteriosclerotic index(the hazardous factor),and the vegetative nerve function ofregulating the heart and blood vessels(the equilibrium indices of the vegetative nervous system).All this suggests that acupuncture is a treatment of choice for obesity and an important methodof preventing and treating complicating cardiovascular diseases. 展开更多
关键词 ACUPUNCTURE MOXIBUSTION obesity cardiovascular VEGETATIVE hazardous treating OBESE complicating regulating
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