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Administrative division system changes and urbanization in China
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作者 LI Ling Centre for Urban and Regional Studies, Zhongshan University, Guangzhou 510275 CHINA 《Journal of Geographical Sciences》 SCIE CSCD 1998年第4期58-65,共8页
s—This paper ana1yses the relationship between the administrative division system changes (ADSC) and the urbanization process in China, especially in Guangdong Province since the 1980s. It points out that there are t... s—This paper ana1yses the relationship between the administrative division system changes (ADSC) and the urbanization process in China, especially in Guangdong Province since the 1980s. It points out that there are three high tides in ADSC since the 1980s relevant to the changes of economic development. The guiding principle for ADSC is to give local government incentives by transferring more administrative powers to them and bringing along regional development by central city. This paper also discusses problems existed and future prospectives. 展开更多
关键词 administrative division system URBANIZATION China Guangdong.
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Fault diagnosis of spacecraft electrical power system based on improved Newman community divisions method
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作者 Ziyang SONG Zhongcheng MU +2 位作者 Shufan WU Song JIN Jiyuan YI 《Chinese Journal of Aeronautics》 2026年第2期456-471,共16页
The Electrical Power System(EPS)is one of the spacecraft’s key subsystems,and its operational status directly affects the lifespan and performance of the entire spacecraft.The corresponding fault diagnosis has always... The Electrical Power System(EPS)is one of the spacecraft’s key subsystems,and its operational status directly affects the lifespan and performance of the entire spacecraft.The corresponding fault diagnosis has always been the discussion focus to ensure spacecraft reliability.In this paper,a few-shot unsupervised fault diagnosis method based on the improved Newman community division algorithm is proposed,to approach the scarcity of fault data samples and the inconspicuous characteristics of abnormal data.Firstly,aiming to capture the overall relevance of the fault dataset,a complex network model is built by adopting the K-Dynamic time warping distance Adjacent Nodes(KDAN)method.Based on the complex network model,the Newman community divisions algorithm is improved by using the Quantum-behaved Particle Swarm Optimization(QPSO).Subsequently,in order to evaluate the feasibility of the proposed method,experimental validation was conducted using an open-source dataset.The results indicate that the average accuracy can reach 96.43% for fault data diagnosis,and an F1_score of 97.76%with only 17.65%of the dataset used for training.The proposed method can accurately classify abnormal data by identifying the community structure in the data network,significantly improve the efficiency of the community divisions algorithm and reduce its complexity,and provide a new solution for fault diagnosis in large-scale complex systems. 展开更多
关键词 Community division Complex network Electrical power system Fault detection Quantum-behaved Particle Swarm Optimization SPACECRAFT
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Theoretical Mechanisms of New Quality Productive Forces Reshaping the Rural Division of Labor System
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作者 Ximing ZHAO Xiejun CHENG 《Asian Agricultural Research》 2026年第2期19-22,29,共5页
In the context of the coordinated pursuit of"carbon peak and neutrality"objectives,alongside the strategy to establish a robust agricultural nation,the economic and social development of rural areas is under... In the context of the coordinated pursuit of"carbon peak and neutrality"objectives,alongside the strategy to establish a robust agricultural nation,the economic and social development of rural areas is undergoing a profound paradigm shift.The traditional rural division of labor pattern,which depends on tangible factors such as land,labor,and capital,has increasingly encountered developmental challenges characterized by diminishing marginal returns and a detrimental cycle of internal competition.The new quality productive force,centered on data,algorithms,green technologies,bioengineering,and clean energy,offers a potential pathway for the rural division of labor system to overcome the"low-level equilibrium".This force is characterized by attributes such as non-exclusivity,replicability,network collaboration,and ecological compatibility.This paper develops a three-dimensional collaborative analytical framework encompassing"technology,institution,and culture".It systematically elucidates the internal logic by which new quality productive forces drive the transformation of the rural division of labor from"quantitative factor matching"to"qualitative structural reorganization"through three principal mechanisms:technology embedding,institutional reconstruction,and cultural coupling.Furthermore,the study proposes corresponding policy recommendations,thereby offering theoretical insights to support the modernization of China s agriculture and rural areas,as well as the development of a strong agricultural country. 展开更多
关键词 New quality productive force Rural division of labor system Technology embedding Institutional reconstruction Cultural coupling
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Phase matching sampling algorithm for sampling rate reduction in time division multiplexing optical fiber sensor system
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作者 Junhui Wu Zhilin Xu +2 位作者 Yi Shi Yurong Liang Qizhen Sun 《Opto-Electronic Technology》 2025年第2期51-63,共13页
Time division multiplexing(TDM)architecture is an important approach to creating sensor arrays for massive scale monitoring.But it is paradoxical for the TDM interferometric sensor array to keep a short delay fiber fo... Time division multiplexing(TDM)architecture is an important approach to creating sensor arrays for massive scale monitoring.But it is paradoxical for the TDM interferometric sensor array to keep a short delay fiber for high sensing resolution and meanwhile use low sampling rate for practical applications.In this paper,a phase matching sampling(PMS)paradigm is proposed to address the above contradiction.By matching the phase of the sampling clock with the delay fiber length,combining with multiple-pulses sampling strategy,the proposed PMS method can avoid collecting the redundant information,facilitating the decreasing of sampling rate as well as delay fiber length of the TDM sensing system.The proof-of-concept experiments on an 8-channel TDM interferometric system demonstrate that when the sampling rate is fixed at 20 MS/s,by applying the PMS algorithm,the delay fiber length can be shortened from 100 m to 1 m,compared with applying the conventional sampling method.It reduced the phase noise of the system by a factor of 10 at 1 mHz and by a factor of 50 at 1 Hz.The PMS algorithm for greatly reducing the sampling rate is expected to fuel the TDM interferometric sensor arrays for many applications. 展开更多
关键词 time division multiplexing system sampling algorithm interferometric fiber optic sensors displacement sensing array
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SUPPORT SYSTEM FOR FREE SURFACE GRINDING BASED ON PATCH DIVISION
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作者 吴晓君 喜田羲宏 孙树栋 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第4期291-297,共7页
To obtain accurate forms and surfaces in free surface grinding, it is important to provide grinding conditions suitable for a curved surface. A grinding support system for the free surface (GSX-F) is proposed to hel... To obtain accurate forms and surfaces in free surface grinding, it is important to provide grinding conditions suitable for a curved surface. A grinding support system for the free surface (GSX-F) is proposed to help the operator grind a free surface with the high accuracy and the high productivity. To succeed in free surface grinding, the property of a ball type wheel must be known. Therefore, a basic study of free surface grinding with a ball type wheel is carried out based on the grinding center (GC). Some working points for achieving sufficient accuracy in free surface grinding are discussed. GSX-F is constructed using the patch division method and is used to test grinding. Reasonable results are obtained. 展开更多
关键词 grinding center ball type wheel support system free surface grinding patch division
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What Role Will China Play in the World Labor Division System?
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作者 Huang Fanzhang, Senior Research Fellow, Academy of Macroeconomic Research, State Development and Reform Commission. 《China & World Economy》 SCIE 2003年第4期44-50,共7页
Since the 1990s, the Chinese economy has main-tained strong growth momentum despite the compli-cated and cjamgeable international environment. Duringthe 1989-2001 period, the average annual growth rate ofthe Chinese e... Since the 1990s, the Chinese economy has main-tained strong growth momentum despite the compli-cated and cjamgeable international environment. Duringthe 1989-2001 period, the average annual growth rate ofthe Chinese economy was 9.3 percent, making China oneof the fastest growing economies of the world (NBS,2002). 展开更多
关键词 in World What Role Will China Play in the World Labor division system that is PLAY of THAN for
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APPLICATION OF MAP AND FILE INFORMATIONVISUALIZATION SYSTEM TO COMPREHENSIVEDIVISION OF NATURAL DISASTERS- Takingthe ChangjiangValleg as an Example 被引量:4
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作者 HU Bao-qing1,4, JIANG Mei-xin2, JUN Su-lan3, ZENG Qiao-song4 ( 1. Department of Geography, Guangxi Normal College, Narming 530001, P. R. China 2. Department of Resource and Environment Sciences, Jiangxi Normal University, Nanchang 3300 《Chinese Geographical Science》 SCIE CSCD 2001年第4期40-49,共10页
ABSTRACT: This paper generalizes the makeup and forming dynamic mechanism of natural disaster systems, principles and methods of comprehensive division of natural disasters, as well as structure, function and up-build... ABSTRACT: This paper generalizes the makeup and forming dynamic mechanism of natural disaster systems, principles and methods of comprehensive division of natural disasters, as well as structure, function and up-build routes of map and file information visualization system (MFIVS). Taking the Changjiang(Yangtze) Valley as an example, on the basis of revealing up the integrated mechanism on the formations of its natural disasters and its distributing law, thereafter, the paper relies on the MFIVS technique, adopts two top-down and bottom-up approaches to study a comprehensive division of natural disasters. It is relatively objective and precise that the required division results include three natural disaster sections and nine natural disaster sub-sections, which can not only provide a scientific basis for utilizing natural resources and controlling natural disaster and environmental degradation, but also be illuminated to a concise, practical and effective technique on comprehensive division. 展开更多
关键词 KEYWORDS: MAP and FILE information visualization system (MFIVS) natural DISASTER systems damage evaluation comprehensive division the CHANGJIANG VALLEY
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CDP1, a novel component of chloroplast division site positioning system in Arabidopsis 被引量:5
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作者 Min Zhang Yong Hu +4 位作者 Jingjing Jia Dapeng Li Runjie Zhang Hongbo Gao Yikun He 《Cell Research》 SCIE CAS CSCD 2009年第7期877-886,共10页
Chloroplasts are plant-specific organelles that evolved from endosymbiotic cyanobacteria. They divide through binary fission. Selection of the chloroplast division site is pivotal for the symmetric chloroplast divisio... Chloroplasts are plant-specific organelles that evolved from endosymbiotic cyanobacteria. They divide through binary fission. Selection of the chloroplast division site is pivotal for the symmetric chloroplast division. In E. coli, positioning of the division site at the midpoint of the cell is regulated by dynamic oscillation of the Min system, which includes MinC, MinD and MinE. Homologs of MinD and MinE in plants are involved in chloroplast division. The homolog of MinC still has not been identified in higher plants. However, an FtsZ-like protein, ARC3, was found to be involved in chloroplast division site positioning. Here, we report that chloroplast division site positioning 1 (AtCDP1) is a novel chloroplast division protein involved in chloroplast division site placement in Arabidopsis. AtCDP1 was discovered by screening an Arabidopsis cDNA expression library in bacteria for colonies with a cell division phenotype. AtCDP1 is exclusively expressed in young green tissues in Arabidopsis. Elongated chloroplasts with multiple division sites were observed in the loss-of-function cdpl mutant. Overexpression of AtCDP1 caused a chloroplast division phenotype too. Protein interaction assays suggested that AtCDP1 may mediate the chloroplast division site positioning through the interaction with ARC3. Overall, our results indicate that AtCDP1 is a novel component of the chloroplast division site positioning system, and the working mechanism of this system is different from that of the traditional MinCDE system in prokaryotic cells. 展开更多
关键词 ARABIDOPSIS chloroplast division AtCDP1
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Genomic Instability in Cancer I: DNA-Repair Triggering Primitive Hereditary 4n-Skewed, Amitotic Division-System, the Culprit in EMT/MET/Metaplasia Cancer-Concepts 被引量:3
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作者 Kirsten H. Walen 《Journal of Cancer Therapy》 2018年第12期974-997,共24页
The objective was to gain proof of genome damage-repair induced mitotic slippage process (MSP) to 4n-diplochromosome skewed division-system, earlier suggested to have “cancer-deciding” consequences. Our damage-model... The objective was to gain proof of genome damage-repair induced mitotic slippage process (MSP) to 4n-diplochromosome skewed division-system, earlier suggested to have “cancer-deciding” consequences. Our damage-model showed two succeeding phases: molecular mutations for initiation of fitness-gained cells, and large chromosomal changes to aneuploidy from inherited DNA-breakage-repair inaccuracies. The mutations were gained while DNA-repair and DNA-replication, co-existed in the route to tetraploidy, a phenomenon also expressed for some existing unicellular organisms. These organisms also showed genome reductive, amitotic, meioticlike division, and was the origin of human genome conserved, self-inflicted 90° reorientation of the 4n nucleus relative to the cytoskeleton axis. In the in vitro DNA-damage model, this remarkable 4n-event deciding “flat-upright” cell-growth characteristics showed several consequences, for example, cancer-important, E-cadherin-β-catenin cell-to-cell adherence destruction, which gave diploid progeny cells, mobility freedom from cell contact inhibition, likely in renewal tissues. This 4n-skewed division-system with inheritance in progeny cells for repeat occurrences as mentioned for flat-up-right growth patterns is similar to claimed concepts of metaplasia-EMT/MET embryogenesis events in cancer evolution. A scrutiny of this literature, proof-wise invalidated this embryological concept by tetraploid 8C cells occurring in MET events and, was noted for small cell occurrence, i.e., diploidy from 4n-8C reductive division, an also event for tumor relapse cells, derived from genome damaging therapy agents. Pre-cancer hyperplasia reported MSP, cadherincatenin destruction and 90° perpendicularity to basal cell membrane. The DNA-damage-repair model can weed-out therapy-agents triggering 4n-skewed division. Cancer-control, beginning-information, is likely from mutational identity of the 4n derived fitness-gained cells. 展开更多
关键词 CANCER Evolution DNA-Damage-Repair Mitotic Slippage HEREDITARY PRIMITIVE Tetraploidy 90° Amitotic Skewed division Fitness-Gain Embryogenesis-Type EMT/MET Human Cell Conservation
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Analysis and Simulation for Capacity of Time Division-Synchronous Code Division Multiple Access System 被引量:1
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作者 Sun Chengjun, Zhang Zhongzhao, Ba Yong2 & Cao Pengzhi (Communication Research ("enter, Harbin Institute of Technology, Harbin 150001, P. R. China Department of Electronic Engineering, Tsinghua University, Beijing 100084, P. R. China Research and Development Division, Shanghai Bell Company Limited, Shanghai 200092, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2002年第4期91-97,共7页
Capcity both in uplink and downlink of TD-SCDMA (time division-synchronous code division multiple access) system is studied in a multi-cell environment. The theoretical expressions of the mean of intercell interferenc... Capcity both in uplink and downlink of TD-SCDMA (time division-synchronous code division multiple access) system is studied in a multi-cell environment. The theoretical expressions of the mean of intercell interference in uplink and the mean of sum of power allocation in downlink are given, by which uplink and downlink capacity is analyzed. Furthermore, we give the simulation models for both uplink and downlink capacity. The results from theoretical analysis and simulation fit very well. In the end, the maximum number of users that TD-SCDMA system can serve for 12.2 k speech service is given. 展开更多
关键词 Code division multiple access PROBABILITY Resource allocation SIMULATION Time division multiple access
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Groundwater System Division and Description of Asia 被引量:1
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作者 ZHANG Fawang YI Qing +2 位作者 CHENG Yanpei YUE Chen DONG Hua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第4期1434-1443,共10页
Based on landform,climate,river system,geological structure and hydrogeological structure and from the perspective of systematology,the groundwater system of Asia can be divided into 36 secondary groundwater systems u... Based on landform,climate,river system,geological structure and hydrogeological structure and from the perspective of systematology,the groundwater system of Asia can be divided into 36 secondary groundwater systems under 11 primary ones by the intercontinental scale.This forms part of the work of the groundwater series map of Asia,which is compiled according to groundwater system division and evaluation of the total amount and types of aquifer,reflecting the large-scale features of groundwater resources in Asia.Systematic profiling of groundwater in this way provides a scientific basis for groundwater exploitation planning and management in Asia,and avoiding disputes over groundwater resources and the environment among Asian countries. 展开更多
关键词 ASIA groundwater system climate and topography division
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Rural labor migration and farmers’arrangements of rice production systems in Central China:Insight from the intergenerational division of labor 被引量:1
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作者 Xue Shen Quanyu Yang +1 位作者 Rongjun Ao Shengsheng Gong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期3200-3214,共15页
Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied extensively.Labor migration in rural China has taken new forms in recent years.There has been a di... Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied extensively.Labor migration in rural China has taken new forms in recent years.There has been a discernible trend wherein adult children have started migrating to cities while their elderly parents return to villages to re-engage in on-farm work.The phenomenon has notably shaped the intergenerational division of labor(IDL)within households.However,it remains to be seen how farmers adjust their rice production systems in response to the IDL.The age of 60 years for employment injury insurance is the eligibility threshold for off-farm employment and is used to obtain a source of exogenous variation in the IDL.Based on a representative household survey of 1,752 rice farmers in the Hubei Province of Central China,our fuzzy regression discontinuity analysis reveals that farmers in IDL households are more likely to adopt ratoon rice(RR)than single cropping rice(SR)or double cropping rice(DR).The effect of the IDL varies under different levels of operational scales and specialized agricultural service availability.Further analysis suggests that farmers’arrangements are associated with two potential mechanisms of downward intergenerational transfer.Monetary transfer for urban housing purchases increases RR in IDL households,and time transfer for intergenerational childcare significantly promotes SR in IDL households.This study enhances the understanding of the relationship between rural labor migration and rice production in China,providing a reference for adjusting rice production systems to ensure food security. 展开更多
关键词 labor migration intergenerational division of labor rice production systems fuzzy regression discontinuity Central China
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Realization of 40 GHz Short Time Windows and Their Applications in High Speed Optical Time Division Multiplexing Systems 被引量:1
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作者 Li Yan Wu Jian 《China Communications》 SCIE CSCD 2012年第8期40-51,共12页
Optical Time Division Multiplexing (OTDM) is known to be capable of transmitting single channel high bit rate data stream with low speed electro-optical components. A cost-effective, compact and stable short time wi... Optical Time Division Multiplexing (OTDM) is known to be capable of transmitting single channel high bit rate data stream with low speed electro-optical components. A cost-effective, compact and stable short time window with low insert loss, low phase noise, low timing-jitter and high speed performance is essential for ultra-high speed OTDM systems using phase and amplitude modulation formats. In this paper, we review three promising methods to obtain 40 GHz short time window including Electro-Absorption Modulator (EAM), Dual-Parallel Mach-Zehnder Modulator (DPMZM) and Fiber Loop-Polarization Modulator (FL-PolM). Sub-picosecond short pulse source generation, optical time division denlaltiplexing and clock recovery are realized respectively by using the short time window based on the three methods. By using DPMZM based pulse source and EAM based Clock Recovery (CR) and dermltiplexer, error free transmission of 640 Goit/s (160 Gbaud/s Pol-Mux DQPSK) single channel signal over 400 km single mode fiber is proven to be experimentally successful. 展开更多
关键词 optical fiber conmmnication optical time division nmltiplexing optical tirre switch
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QSM-IDM -A novel quadrature spatial modulation based on interleaving division multiplexing for multiple antenna system 被引量:1
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作者 Sherif K. El Dyasti Esam A.A. Hagras Hadia El-Hennawy 《Digital Communications and Networks》 SCIE 2019年第3期183-188,共6页
Quadrature Spatial Modulation (QSM) is a high spectral efficiency Multiple-Input Multiple Output (MIMO) technique used to improve the spectral efficiency of wireless communication systems. The main concept of QSM is t... Quadrature Spatial Modulation (QSM) is a high spectral efficiency Multiple-Input Multiple Output (MIMO) technique used to improve the spectral efficiency of wireless communication systems. The main concept of QSM is to extend the spatial constellation of the conventional Spatial Modulation (SM) in both the in-phase and quadrature components of the data symbol. In this paper, because QSM-based on Interleaxdng Division Multiplexing (IDM) has not been introduced in the literature as a multiple antenna system, we introduced a novel scheme, called QSM system based on Interleaving Division Multiplexing (QSM-IDM). The antenna sets are also applied to a spreader, before being used to assign an antenna number for information transmission. Analysis and simulations for a flat fading channel show that the proposed QSM-IDM method significantly outperforms the original QSM system with the same data rate, while maintaining a relatively acceptable complexity. The obtained simulation results show that the conducted analysis yields significant improvements for the accuracy of the proposed scheme, with satisfactory complexity. 展开更多
关键词 Interleaver division MULTIPLEXING (IDM) MULTIPLE Input MULTIPLE Output (MIMO) Spatial MODULATION (SM) QUADRATURE Spatial MODULATION (QSM)
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Division of Ecosystem Sensitivity of Natural Landscape in Lower Reaches of Tarim River
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作者 阿斯卡尓江.司迪克 楚新正 +1 位作者 艾里西尔.库尓班 古力米热.吐拉洪 《Journal of Landscape Research》 2010年第8期1-4,10,共5页
By choosing aerial and satellite remote sensing images of the year 1959, 1973, 1989, 2000 and 2008 as data source, combining ground investigation, landscape in lower reaches of Tarim River was classified and landscape... By choosing aerial and satellite remote sensing images of the year 1959, 1973, 1989, 2000 and 2008 as data source, combining ground investigation, landscape in lower reaches of Tarim River was classified and landscape classification map was promoted by using GIS technique and landscape ecology theory. Finally landscape classification maps of the five years would be converted into gray scale images which would be used for overlay analysis, and based on this, landscape ecosystem sensitive zone had been identified. The result showed that the extremely sensitive zone took up 10.18% of the study area and sensitive zone occupied 17.95% of the study area. Ecological system of natural landscape in the lower reaches of Tarim River was superior to ecological system of artificial landscape in terms of resistance to wind, dust, salt and drought. Study on division of ecosystem sensitivity area of natural landscape not only provided scientific reference for the formulation of regional policies to prevent and treat ecological environmental problems, but also was beneficial for people to identify treatment focus of ecological environmental problems in different regions and propose countermeasures ameliorating regional ecological environment. 展开更多
关键词 LOWER reaches of TARIM River Natural LANDSCAPE division of SENSITIVE area
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Exploiting the Faster-Than-Nyquist Concept in Wavelength-Division Multiplexing Systems Using Duobinary Shaping 被引量:1
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作者 Ekawit Tipsuwannakul Magnus Karlsson Peter A. Andrekson 《ZTE Communications》 2012年第1期23-29,共7页
This paper begins with Nyquist wavelengthdivision multiplexing (WDM) and then introduces fasterthanNyquist. In fasterthanNyquist a certain amount of intersymbol interference (ISI) is accepted, which violates the f... This paper begins with Nyquist wavelengthdivision multiplexing (WDM) and then introduces fasterthanNyquist. In fasterthanNyquist a certain amount of intersymbol interference (ISI) is accepted, which violates the fundamental principle of Nyquist WDM. This results in muchrelaxed transceiver bandwidth and simpler spectral design. However, in fasterthanNyquist, implementation complexity is shifted from the transmitter side to the receiver side. Therefore, successful application of fasterthanNyquist depends on innovation in the receiver structure. In this paper, we discuss the guidelines for implementing suboptimum, lowcomplexity receivers based on fasterthanNyquist. We suggest that duobinary shaping is a good technique for trading off achievable spectral efficiency, detection performance, and implementation complexity and might be preferable to Nyquist WDM. Experiments are conducted to verify robustness of the proposed technique. 展开更多
关键词 coherent detection digital signal processing optical fiber communications spectralefficiency wavelength division multiplexing
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Performance Evaluation of Wavelength Division Multiplexing Photonic Analogue-to-Digital Converters for High-Resolution Radar Systems 被引量:1
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作者 Pedro E. D. Cruz Tiago M. F. Alves Adolfo V. T. Cartaxo 《Optics and Photonics Journal》 2019年第12期219-234,共16页
The performance of the wavelength division multiplexing (WDM) photonic analogue-to-digital converter (ADC) used for digitization of high-resolution radar systems is evaluated numerically by using the peak signal-to-no... The performance of the wavelength division multiplexing (WDM) photonic analogue-to-digital converter (ADC) used for digitization of high-resolution radar systems is evaluated numerically by using the peak signal-to-noise ratio (SNR) metric. Two different WDM photonic ADC architectures are considered for the digitization of radar signals with 5 GHz of bandwidth (spatial resolution of 3 cm), in order to provide a comprehensive study of the compromises present when deploying radar signals with high-resolution: 1) a four-channel architecture with each channel employing an ADC with 5 GSamples/s, and 2) an eight-channel architecture with each channel employing an ADC with 2.5 GSamples/s. For peak powers of the pulsed source between 10 and 20 dBm and a distance between the radar antenna and the sensing object of 2.4 meters, peak SNR levels between 29 and 39 dB are achieved with the eight-channel architecture, which shows higher peak SNR levels when compared with the four-channel architecture. For the eight-channel architecture and for the same peak powers of the pulsed source, peak SNR levels between 11 and 16 dB are obtained when the distance increases to 13.5 meters. With this evaluation using the peak SNR, it is possible to assess the performance limits when choosing a specific radar range, while keeping the same resolution. 展开更多
关键词 Analogue-to-Digital Converter Radar SIGNAL-TO-NOISE Ratio WAVELENGTH division MULTIPLEXING
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On division management for environmental system of China: lessons from European local sustainable development 被引量:1
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作者 Bai Yongqing Hao Jingxia Zhu Xiancheng 《Ecological Economy》 2006年第2期190-195,共6页
The concept of sustainable development, after being brousht forward, has become a shibboleth in the world, at national and local levels. In Europe, this concept is implemented from the local to tha nation, even to the... The concept of sustainable development, after being brousht forward, has become a shibboleth in the world, at national and local levels. In Europe, this concept is implemented from the local to tha nation, even to the Continent. The local sustainable development mainly consists in two factors: one is the renovating method continually invented by European Secretariot of ICLEI, and the other is that the local authorities towards sustainability are co-operated by the European Sustainable Cities and Towns Campaign. The coo-budget method is the outcome of tbese factors, For our country is a big country, on rapid progression of indastrialization and urbanization, with a large population and scarce resoarces per capita, it is practically significance to study us soon as possible the methodology. Experience from European local sustainable development may help us to resolve the handicap of departraent division in local a, tbority. 展开更多
关键词 Local sustainable development Europe China Environmental management Department division
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Multi-functional optical fiber sensor system based on a dense wavelength division multiplexer
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作者 Yue-Xin Yin Zhifa Wu +4 位作者 Siwen Sun Liang Tian Xibin Wang Yuanda Wu Daming Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期222-224,共3页
We propose a novel and efficient multi-functional optical fiber sensor system based on a dense wavelength division multiplexer(DWDM).This system consists of an optical fiber temperature sensor, an optical fiber strain... We propose a novel and efficient multi-functional optical fiber sensor system based on a dense wavelength division multiplexer(DWDM).This system consists of an optical fiber temperature sensor, an optical fiber strain sensor, and a 48-channel DWDM.This system can monitor temperature and strain changes at the same time.The ranges of these two sensors are from-20℃ to 100℃ and from-1000 με to 2000 με, respectively.The sensitivities of the temperature sensor and strain sensor are 0.03572 nm/℃ and 0.03808 nm/N, respectively.With the aid of a broadband source and spectrometer,different kinds and ranges of parameters in the environment can be monitored by using suitable sensors. 展开更多
关键词 DENSE wavelength division multiplexer(DWDM) planar LIGHTWAVE circuit multi-functional SENSOR optical fiber SENSOR system
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