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| 1 | Study of spatial distribution of sandy desertification in North China in recent 10 years显示文摘Sandy desertification is a land degradation characterized by wind erosion, mainly resulted from the excessive human activities in arid, semiarid and part of sub-humid regions in North China. It is one of main kinds of desertification/land degradation as well as water-soil erosion and salinization in China. Rapid and continuous spread of sandy desertification during last 50 years has created a major environmental and socio-economic problem in North China. Remote sensing monitored results in 2000 showed that the sandy desertified land area has been 38.57×104 km2. The area of potential to slightly sandy desertified land is 13.93×104 km2, moderately land 9.977×104 km2, severely land 7.909×104 km2 and very severely land 6.756×104km2. Sandy desertification mainly occurs in the semi-arid mixed farming-grazing zone and its northern rangeland zone, semi-arid dryland rainfed cropping zone and arid oasis-desert margin zone. The average annually developmental rate of sandy desertified land increased from 2,100tion in North China is 'overall deterioration, while local rehabilitation'. Already achieved rehabilitation results and monitoring assessment show that about 60% of desertified land in North China can be restored under the conditions of rational land-use ways and intensity. | WANG Tao, WU Wei, XUE Xian, SUN Qingwei & CHEN GuangtingKey Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China Department of Environment Engineering, Peking University, Beijing 100871, China | 2004 | Science China Earth Sciences2004，47，z1： | 28 |
| 2 | 基于Fisher子空间特征提取的间歇过程监控和故障诊断显示文摘Multivariate statistical process control methods have been widely used in biochemical industries. Batch process is usually monitored by the method of multi-way principal component analysis (MPCA). In this article, a new batch process monitoring and fault diagnosis method based on feature extract in Fisher subspace is proposed.The feature vector and the feature direction are extracted by projecting the high-dimension process data onto the low-dimension Fisher space. The similarity of feature vector between the current and the reference batch is calculated for on-line process monitoring and the contribution plot of weights in feature direction is calculated for fault diagnosis. The approach overcomes the need for estimating or tilling in the unknown portion of the process variables trajectories from the current time to the end of the batch. Simulation results on the benchmark model of penicillin fermentation process can demonstrate that in comparison to the MPCA method, the proposed method is more accurate and efficient for process monitoring and fault diagnosis. | 赵旭 阎威武 邵惠鹤 | 2006 | Chinese Journal of Chemical Engineering2006，14，6： | 4 |
| 3 | Optimal locations of monitoring stations in water distribution systems under multiple demand patterns: a flaw of demand coverage method and modification显示文摘A flaw of demand coverage method in solving optimal monitoring stations problem under multiple demand patterns was identified in this paper. In the demand coverage method, the demand coverage of each set of monitoring stations is calculated by accumulating their demand coverage under each demand pattern, and the impact of temporal distribution between different time periods or demand patterns is ignored. This could lead to miscalculation of the optimal locations of the monitoring stations. To overcome this flaw, this paper presents a Demand Coverage Index (DCI) based method. The optimization considers extended period unsteady hydrau- lics due to the change of nodal demands with time. The method is cast in a genetic algorithm framework for integration with Environmental Protection Agency Net (EPANET) and is demonstrated through example applica- tions. Results show that the set of optimal locations of monitoring stations obtained using the DCI method can represent the water quality of water distribution systems under multiple demand patterns better than the one obtained using previous methods. | Shuming LIU Wenjun LIU Jinduan CHEN Qi WANG | 2012 | Frontiers of Environmental Science & Engineering2012，6，2： | 3 |
| 4 | Characteristics and Warning Indexes of Rice Seeds Viability Loss During Storage at 45℃ Constant Temperature显示文摘Seed aging characteristics of rice was investigated in this study. Seeds of 34 japonica rice (O-ryza sativa subsp. japonica) varieties were held at 45℃ constant temperature. Changes in seed viability and seed vigor during aging process were measured to study seed viability-losing characteristic and to determine warning index for seed viability loss. As a result, seed viability survival curves were obtained across different rice accessions at 45℃ constant temperature. The curves appeared to be contra-sigmoid survival curves. The loss of seed viability in the aging process consisted of two phases. The first phase took a long duration, in which the viability of vigorous seeds declined slowly. In the second phase, seed viability declined rapidly. It was obvious that seed viability declined inconsistently during storage. It also showed that seed germination was prolonged and the seedling was significantly weakened before the coming of the rapid declining phase of seed viability. These two parameters could be used to indicate seed quality during storage. The rate of compatibility of tests (RCT), coefficient of variation (CV), vigor of seedling, the day the seeds start to germinate could be used as warning indexes to indicate overall quality of a mass of accessions. These warning indexes could also be used in monitoring the viability of seeds stored in the seed genebank. | LU Xin-xiong and CHEN Xiao-ling(Key Laboratory for Crop Germplasm and Biotechnology of Agricultural Ministry, Institute of Crop Germplasm Resources, Chinese Academy of Agricultural Sciences, Beijing 100081, P.R.China) | 2002 | Agricultural Sciences in China2002，1，8： | 2 |
| 5 | Entropy-Based Approach to Remove Redundant Monitoring Wells from Regional-Scale Groundwater Network显示文摘An entropy based approach is applied to identify redundant wells in the network. In the process of this research, groundwater monitoring network is considered as a communication system with a capability to transfer information, and monitoring wells are taken as information receivers. The concepts of entropy and mutual information are then applied to measure the information content of individual monitoring well and information relationship between monitoring well pairs. The efficiency of information transfer among monitoring wells is the basis to judge the redundancy in the network. And the capacity of the monitoring wells to provide information on groundwater is the point of evaluation to identify redundant monitoring wells. This approach is demonstrated using the data from a regional scale groundwater network in Hebei plain, China. The result shows that the entropy based method is recommendable in optimizing groundwater networks, especially for those within media of higher heterogeneities and anisotropies. | Chen Zhihua Engineering Faculty, China University of Geosciences, Wuhan 430074 Jing Juanli Graduate School, China University of Geosciences, Wuhan 430074 Chen Gang Engineering Faculty, China University of Geosciences, Wuhan 430074 | 2002 | Journal of China University of Geosciences2002，13，3： | 1 |
| 6 | Variations of near-surface atmospheric CO_(2)and H_(2)O concentrations during summer on Muztagata显示文摘Expeditions during the summers of 2002 and 2003 implemented continuous monitoring of near-surface (2 m height) atmospheric CO2 and H2O concentrations at the 4500 m elevation on Muztagata. The resultant data sets reveal a slight decrease of CO2 concentrations (of about 5 μmol·mol?1) and changes in the diurnal variations from the end of June to the middle August. The daily maximum CO2 concentrations occur between 02:30―05:30 AM (local time) and the minimum levels occur between 12:00―15:30 PM. The atmospheric CO2 concentrations in the summer of 2002 were around 5 μmol·mol?1 lower than those during the same period of 2003, whereas the diurnal amplitude was higher. In contrast, we found that the daily mean atmospheric H2O content in 2003 was much lower than that in 2002 and there exists a striking negative correlation between CO2 and H2O con-centrations. We therefore suggest that the near-surface atmospheric CO2 concentration is affected not only by photosynthesis and respiration, but also by the air H2O content in the glaciated region around Muztagata. | XU Baiqing1,2, YAO Tandong1,2, LU Anxin2, GUO Xuejun, LIU Xianqin2 & LI Zhen2 1. Laboratory of Environment and Process on Tibetan Plateau, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China 2. Key Laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering Research Institute and Institute of Tibetan Plateau Research, Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences, China Meteorological Administration, Lanzhou 730000, China | 2006 | Science China Earth Sciences2006，49，1： | 1 |
| 7 | Crowd Monitoring System Using Unmanned Aerial Vehicle (UAV)显示文摘Understanding and dealing with safety aspects of crowd dynamics in mass gatherings of people related to sports, religiousand cultural activities is very important, specifically with respect to crowd risk analysis and crowd safety. Historical trends from theKingdom of Saudi Arabia hosting millions of pilgrims each year during the Hajj and Omrah seasons suggest that stampedes in massgatherings occur frequently and highlight the importance of studying and dealing with the crowd dynamics more scientifically. In thisregard, efficient monitoring and other safe crowd management techniques have been used to minimize the risks associated with suchmass gathering. An example of these techniques is real-time monitoring of crowd using a UAV (Unmanned Aerial Vehicle); thistechnique is becoming increasingly popular with the objective to save human lives, preserve environment, protect property, keep thepeace, and uphold governmental authority. In this paper, a crowd monitoring system for pedestrians has been proposed and tested. Thesystem has deployed crowd monitoring technique using real-time images taken by UAVs; the collected data was investigated, andcrowd density was estimated using image segmentation procedures. A color-based segmentation method has been employed to detect,identify and map crowd density under different camera positions and orientations. Furthermore, the associated anomalies/outlierswhich may lead to non-classification of features have been eliminated using image enhancement tools. The paper presents a crowdmonitoring system for pedestrians that can contribute to an area of research still in its infancy. The proposed system is a valuable tool interms of facilitating timely decisions, based on highly accurate information. The results show that the used image segmentationtechnique has the capability of mapping the crowd density with an accuracy level up to 80%. | Ali A1-Sheary Ali Almagbile | 2017 | Journal of Civil Engineering and Architecture2017，11，11： | 0 |
| 8 | THE SPACE APPLICATION ACHIEVEMENTS OF THE CHINESE UNMANNED SPACECRAFT 'SZ-3'显示文摘During the 3rd mission of Chinese Unmanned Spacecraft the application sys tem of 'SZ-3' (Shenzhou, a divine ship) gets a great success, all its goals are achieved. Many areas of science and breakthrough technology, including earth observation, earth environment monitoring, space material, space life science etc., are carried out in the mission. There are 44 payload instruments totally.All the instruments are working well during the orbit flight and a lot of good results are obtained. Many areas, for example the moderate resolution imag ing spectroradiometer, the solar ultraviolet spectral irradiance monitor and the space protein crystallization facility perform better than required and expected.A brief introduction of the experiments and the achievements of the mission is given in this paper. | SUN Huixian | 2002 | 空间科学学报2002，22，z1： | 0 |
| 9 | A Web-based Condition Monitoring and Diagnostic System of Rolling Mill显示文摘A web based condition monitoring and fault diagnosis system (CMAFDS) for the F2 finishing mill of the 2050 Hot Strip Mill was developed at a steel works. The features of the condition monitoring and fault diagnosis system based on the Web are analyzed in this paper. This paper also describes the main frame of the hardware and the software in the system and emphatically points out the function of the database management system(DBMS) based on the Web. It is proved that the web based CMAFDS is practical in technology and much superior to the CMAFDS based on other network technology in functions. | XIONG Liang cai, HE Lin song, SHI Tie lin, YANG Shu zi Huazhong University of Science and Technology, Wuhan 430074, P.R.China | 2002 | International Journal of Plant Engineering and Management2002，7，1： | 0 |
| 10 | Tool Wear Monitoring in Drilling Using Multiple Feature Fusion of the Cutting Force显示文摘This paper presents a tool wear monitoring method in drilling process using cutting force signal. The kurtosis coefficient and the energy of a special frequency band of cutting force signals were taken as the signal features of tool wear as well as the mean value and the standard deviation from the time and frequency domain. The relationships between the signal feature and tool wear were discussed; then the vectors constituted of the signal features were input to the artificial neural network for fusion in order to realize intelligent identification of tool wear. The experimental results show that the artificial neural network can realize fusion of multiple features effectively, but the identification precision and the extending ability are not ideal owing to the relationship between the features and the tool wear being fuzzy and not certain. | ZHENG Jian-ming, LI Yan, HUANG Yu-mei, LI Shu-juan, XIAO Ji-ming, YUAN Qi-long Institute of Mechanical and Precision Instrument Engineering, Xi’an University of Technology, Xi’an 710048, P. R. China | 2001 | International Journal of Plant Engineering and Management2001，6，1： | 0 |
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