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Forecasting Loss of Ecosystem Service Value Using a bp Network: A Case Study of the Impact of the South-to-north Water Transfer Project on the Ecological Environmental in Xiangfan, Hubei Province, China

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Biomedical and Environmental Sciences 2003年第4期16卷 379-391页

作者： YUN-FENG CHEN, JING-XUAN ZHOU, JIE XIAO, AND YAN-PING LIEnvironmental Science and Engineering College, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China Environmental Science and Engineering College Huazhong University of Science and Technology 湖北 Wuhan 430074

Objective To recognize and assess the impact of the South-to-north Water Transfer Project (SNWTP) on the ecological environment of Xiangfan, Hubei Province, situated in the water-out area, and develop sound scientific countermeasures. Methods A three-layer bp network was built to simulate topology and process of the eco-economy system of Xiangfan. Historical data of ecological environmental factors and socio-economic factors as inputs, and corresponding historical data of ecosystem service value (ESV) and GDP as target outputs, were presented to train and test the network. When predicted input data after 2001 were presented to trained network as generalization sets, ESVs and GDPs of 2002, 2003, 2004... till 2050 were simulated as output in succession. Results Up to 2050, the area would have suffered an accumulative total ESV loss of RMB 104.9 billion, which accounted for 37.36% of the present ESV. The coinstantaneous GDP would change asynchronously with ESV, it would go through an up-to-down process and finally lose RMB89.3 billion, which accounted for 18.71% of 2001. Conclusions The simulation indicates that ESV loss means damage to the capability of socio-economic sustainable development, and suggests that artificial neural networks (ANNs) provide a feasible and effective method and have an important potential in ESV modeling.

关键词： Artificial neural network bp Ecosystem service value South-to-north Water Transfer Project

Alterations of mtDNA copy number and 4977 bp deletion induced by ionizing radiation in human peripheral blood

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Nuclear Science and Techniques 2013年第6期24卷 67-73页

作者： LIU Yulong WANG Ping HAN Lin ZHAO Fengling GUO Fei WANG Xiai LYU Yumin The Second Affiliated Hospital of Soochow University Henan Institute of Occupational Medicine College of Public Health Zhengzhou University

Alterations of mitochondria DNA(mtDNA)4977 bp common deletion(CD)and mtDNA copy number induced by ionizing radiation were observed in human different cell lines and total body irradiation ***,only few experiments have evaluated the levels of the CD and mtDNA copy number in human peripheral blood exposed to ionizing radiation till *** aim of this study is to analyze the mtDNA alterations in irradiated human peripheral blood from healthy donors as well as to explore their feasibility as biomarkers for constructing new *** blood samples were collected from six healthy donors,and exposed to 60Co gamma ray with the doses of 0 Gy,1 Gy,2 Gy,3 Gy,4 Gy and 5 *** of the CD and mtDNA copy number in irradiated samples after 2h or 24h incubation were detected using TaqMan real-time PCR,and the CD ratio was *** results showed that the mean of the CD ratio and the CD copy number exhibited a dose-dependent increase 2 h in the dose range from 0–5 Gy,and of the mtDNA copy number significantly increased 24 h in irradiated groups compared with 0 Gy group after *** indicates that the parameters in human peripheral blood may be considered as molecular biomarkers to applying construction of new biodosimeter.

关键词：线粒体DNA 电离辐射诱导人外周血拷贝数分子生物标志物 bp mtDNA 全身照射

GA-bp Air Quality Evaluation Method Based on Fuzzy Theory

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Computers, Materials & Continua 2019年第1期58卷 215-227页

作者： Ma Ning Jianhe Guan Pingzeng Liu Ziqing Zhang Gregory M.P.O’Hare China University of Geoscience Beijing100083China Shandong Agricultural University Taian271018China Shandong Vocational Institute of Fashion Technology Taian271000China University College Dublin(UCD) BelfieldDublin999014Ireland

With the rapid development of China’s economy,the scale of the city has been continuously expanding,industrial enterprises have been increasing,the discharge of multiple pollutants has reached the top of the world,and the environmental problems become more and more *** air pollution problem is particularly *** quality has become a daily concern for *** order to control air pollution,it is necessary to grasp the air quality situation in an all-round *** is necessary to evaluate air *** results of air quality evaluation can help people know more about air *** this paper,refers to previous research results and different evaluation methods,combined with artificial neural network,fuzzy theory,genetic algorithm,GA-bp hybrid algorithm based on fuzzy theory is proposed to evaluate air *** the same time,for the problem that the two-grade standard of air quality annual evaluation is not suitable for practical application,the four-grade standard for annual air quality evaluation has been proposed,and its practicality has been verified through *** setting contrast experiments and comparing the air quality evaluation model based on standard bp algorithm,it is proved that the fuzzy GA-bp evaluation model is better than the standard bp model,both in efficiency and accuracy.

关键词： Air quality evaluation fuzzy theory genetic algorithm bp neural network

Pollen-inferred vegetation and environmental changes since 16.7 ka bp at Balikun Lake, Xinjiang

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Chinese Science Bulletin 2010年第22期55卷 2449-2457页

作者： TAO ShiChen AN ChenBang CHEN FaHu TANG LingYu WANG ZongLi LU YanBin LI ZhiFei ZHENG TongMing ZHAO JiaJu MOR Key Laboratory of West China's Environmental System Lanzhou University Lanzhou 730000 China Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China

A high-resolution fossil pollen record from the sedimentary cores of Balikun Lake, northwestern China, combined with modern surface pollen data, is used to reconstruct the history of vegetation and climatic change since 16.7 cal. ka bp. Fossil pollen assem-blages and lithology indicate that the study area was dominated by desert. The desert had extremely arid climate and lower effec-tive moisture during 16.7–7.9 cal. ka bp, especially from 16.7 to 8.9 cal. ka bp when the lake maybe dried up. During 8.9–7.9 cal. ka bp, the environment gradually recovered in this area. It was then followed by the optimum period from 7.9 to 4.3 cal. Ka bp, when the effective moisture obviously increased. It was characterized by the typical desert-steppe/steppe vegetation and was ac-companied with several patch-birch woodlands around the lake. After that, a short but extremely arid climatic event occurred during 4.3–3.8 cal. ka bp, and the vegetation quickly changed from desert-steppe/steppe to desert. It was a relatively optimum period from 3.8 to 0.53 cal. ka bp showing typical desert-steppe/meadow-steppe landscape. Since 0.53 cal. ka bp, the climate has shown signs of deteriorating again. Furthermore, regional comparison shows that the characteristics of climatic and environmental evolution in this area were clearly different from East Asia monsoonal area during the last 16.7 cal. ka bp. It was characterized by the arid climate during the late-glacial and early Holocene, and relatively wet during the mid-late Holocene.

关键词：环境变化巴里坤湖花粉记录 bp 植被中晚全新世新疆气候变化

A high-resolution environmental change record since 19 cal ka bp in Pumoyum Co, southern Tibet

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Chinese Science Bulletin 2011年第27期56卷 2931-2940页

作者： LU XinMiao ZHU LiPing NISHIMURA Mitsugu MORITA Yoshimune WATANABE Takahiro NAKAMURA Toshio WANG Yong Key Laboratory of Tibetan Environment Changes and Land Surce Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China School of Marine Scinece and Technology Tokai University Shizuoka 424-8610 Japan Botanical Garden Okayama University of Science Okayama 700-0005 Japan Graduate School of Science Tohoku University Sendai 980-8578 Japan Centre for Chronological Research Nagoya University Nagoya 464-8602 Japan Graduate University of Chinese Academy of Sciences Beijing 100049 China

A 380-cm-long sediment core was acquired from the deep water area of Pumoyum Co, southern Tibet. Twenty-five plant residue samples were selected, and organic carbon stable isotopes were obtained using the AMS 14 C chronological method. The 14 C age and carbon reservoir effect were calibrated with surface sedimentation rate measurements using 210 Pb dating. Results showed that the core sediment deposited over 19 cal ka bp. Based on a multi-proxy analysis of TOC and IC contents, grain size and pollen assemblage data, the palaeoclimatic evolution of Pumoyum Co was reconstructed since the last glacial. Pumoyum Co was a shallow lake prior to 16.2 cal ka bp; although the glacier around the lake began to melt due to increasing temperatures, climate was still cold and dry. In the interval of 16.2-11.8 cal ka bp, the sedimentary environment fluctuated drastically and frequently. Two cold-events occurred at 14.2 and 11.8 cal ka bp, and these may correspond to the Older Dryas and the Younger Dryas events, respectively. After 11.8 cal ka bp, Pumoyun Co developed into the deep lake as it is now. The lake water temperature was relatively lower at that time because of influx of cold water from glacial meltwater entering the lake. As a result, the multi-proxy indicators showed no sign of warm conditions. Comparisons between the sedimentary record of Pumoyum Co with that of other lakes of the same age in southern Tibet indicate a warmer climate following the last deglaciation influenced the southeastern Tibetan Plateau. These results imply that the southwest Asian monsoon gradually became stronger since the deglaciation during its expansion to the inner plateau. The glacial-supplied water of the lake responded sensitively to cold-events. The entire southern Tibet region was dominantly influenced climatically by the southwest Asian monsoon during the Holocene.

关键词：西藏南部环境变化 CAL bp 合作高分辨率青藏高原东南部古气候演变

Environmental changes during the past 13500 cal. a bp deduced from lacustrine sediment records of Lake Qinghai, China

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Chinese Journal Of Geochemistry 2011年第4期30卷 479-489页

作者： WANG Yong SHEN Ji XU Xingna LIU Xingqi SIROCKO Frank ZHANG Enlou JI Junfeng State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Nanjing 210008 China Max Planck Institute of Chemistry Mainz 55020 Germany Institute of Geoscience University ofMainz Mainz 55099 Germany School of Geographical Science Southwest University Chongqing 400715 China Department of Earth Sciences Nanjing University Nanjing 210093 China

A 475-cm long sediment core (QH-2005) from Lake Qinghai was used to carry out multi-proxy analysis of δ18O and body length of ostracod valves and redness and grain size of sediments, in order to reconstruct environ-mental changes during the past 13500 cal. a bp. The age model was based on 6 14C dates for bulk orgnic carbon (BOC) and 2 14C dates for lignin. The lignin 14C dates are apparently younger than the corresponding layers' BOC 14C dates, indicating that the reservoir age varied from 728 to 1222 a since the Late Glacial and from 2390 to 2490 a immediately before the pre-bomb era. Hence, the 14C age model for Core QH-2005 was corrected by the changing reservoir age. Ostracod δ18O values were primarily related to dilution and evaporative enrichment of the lake water. The reconstructed salinity based on ostracod body length coincides well with ostracod δ18O values. High redness and mean grain size (MZ) values indicate increased riverine supply to Lake Qinghai associated with increasing monsoon rainfall. Multi-proxy results show that climate during 13500-10900 cal. a bp was relatively cold and dry with fre-quent short-term fluctuations; a warm and wet climate began at about 10900 cal. a bp and culminated around 6500 cal. a bp as a result of monsoon strengthening; the climate became cold and dry afterwards and has remained rela-tively stable since 3400 cal. a bp. Our data also reveal short-term (millennial/centennial timescales) climatic fluctua-tions including: Younger Dryas events, ice-rafting events 8 and 1 (by ～11000 cal. a bp and ～1600 cal. a bp respec-tively), 8200 cal. a bp cold event, Little Ice Age and the Medieval Warm Period.

关键词： CAL 湖泊沉积记录青海湖 bp 环境平均晶粒尺寸气候变化中国

Improving Adaptive Learning Rate of bp Neural Network for the Modelling of 3D Woven Composites Using the Golden Section Law

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Journal of Donghua University(English Edition) 2001年第1期18卷 81-84页

作者： Yi Honglei(易洪雷) Ding Xin(丁辛) College of Textiles Dong Hua University Shanghai 200051 College of Textiles Dong Hua University Shanghai 200051

Focused on various bp algorithms with variable learning rate based on network system error gradient, a modified learning strategy for training non-linear network models is developed with both the incremental and the decremental factors of network learning rate being adjusted adaptively and dynamically. The golden section law is put forward to build a relationship between the network training parameters, and a series of data from an existing model is used to train and test the network parameters. By means of the evaluation of network performance in respect to convergent speed and predicting precision, the effectiveness of the proposed learning strategy can be illustrated.

关键词： bp algorithm, adaptive adjustment, network training parameter, learning strategy, network performance evaluation.

Parameter Self - Learning of Generalized Predictive Control Using bp Neural Network

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Journal of China Textile University(English Edition) 2000年第3期17卷 54-56页

作者：陈增强袁祉王群仙 Dept. of Comp. and Syst. Sci. Nankai Univ. Tianjin 300071 China Dept. of Automat. Hebei Univ. of Technol. Tianjin 300130 China

This paper describes the self—adjustment of some tuning-knobs of the generalized predictive controller(GPC).A three feedforward neural network was utilized to on line learn two key tuning-knobs of GPC,and bp algorithm was used for the training of the linking-weights of the neural *** it gets rid of the difficulty of choosing these tuning-knobs manually and provides easier condition for the wide applications of GPC on industrial *** results illustrated the effectiveness of the method.

关键词： generalized predictive control self - tuning control self - learning control neural networks bp algorithm .

Research on fault location technology based on bp neural network in DWDM optical network

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Optoelectronics Letters 2008年第6期4卷 452-455页

作者： LIAO Xiao-min ZHANG Yin-fa YANG Shi-ping LIN Chu-shan Optical Communication Laboratory of Xi＇an Communication Institute Xi ＇an 710106 China

bp neural network is introduced to the fault location field of DWDM optical network in this paper. The alarm characteris-tics of the optical network equipments are discussed,and alarm vector and fault vector diagrams are generated by analyzing some typical instances. A 17×14×18 bp neural network structure is constructed and trained by using MATLAB. By comparing the training performances,the best training algorithm of fault location among the three training algorithms is chosen. Numerical simulation results indicate that the sum squared error (SSE) of fault location is less than 0.01,and the processing time is less than 100 ms. This method not only well deals with the missing alarms or false alarms,but also improves the fault location accuracy and real-time ability.

关键词：断层定位 DWDM bp 神经网络光学应用