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A New Diabatic Potential Energy Matrix for the Two Lowest Electronic States of H3
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作者 Yingyue Hong Yafu Guan Dong H.Zhang 《Chinese Journal of Chemical Physics》 2025年第1期37-44,I0055,共9页
A new two-state diabatic potential energy matrix(DPEM)for H3 has been constructed,based on the fun-damental invariant neural network(FI-NN)diabatization method pro-posed in our previous work[Phys.Chem.Chem.Phys.21,150... A new two-state diabatic potential energy matrix(DPEM)for H3 has been constructed,based on the fun-damental invariant neural network(FI-NN)diabatization method pro-posed in our previous work[Phys.Chem.Chem.Phys.21,15040(2019)].In that initial effort,a two-state DPEM was constructed only with a 10 eV energy threshold.The current work aims to expand the en-ergy range and improve the accura-cy of DPEM.This is achieved by the utilization of full configuration inter-action(FCI)with aug-cc-pVnZ ba-sis sets and complete basis set(CBS)extrapolation.The original dataset is augmented with additional points with higher adiabatic energies,which give rise to a total of 10985 data points.The DPEM constructed in this work now enables accurate representation of adiabatic energies up to 18 eV.Quantum dynamic calculations based on this DPEM are nearly identical to those obtained from benchmark surfaces,which makes it the most accurate DPEM for the H3 system to date,therefore facilitating detailed exploration of reaction mechanisms at higher collision energies. 展开更多
关键词 Diabatic potential energy matrix Conical intersection Fundamental invariant neural network
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Global Diabatic Potential Energy Surfaces for the Two Lowest States of Li_(3)
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作者 Yingyue Hong Jiayu Huang Dong H.Zhang 《Chinese Journal of Chemical Physics》 2025年第2期172-180,I0039,共10页
We constructed a new set of diabatic poten-tial energy surfaces(PESs)for the two low-est states involved in Li+Li_(2)reaction by us-ing the fundamental-invariant neural net-work method.The Li_(3)system exhibits a coni... We constructed a new set of diabatic poten-tial energy surfaces(PESs)for the two low-est states involved in Li+Li_(2)reaction by us-ing the fundamental-invariant neural net-work method.The Li_(3)system exhibits a coni-cal intersection(CI)at the geometric D_(3)h symmetries with the energy of the CI point significantly lower than the ground-state en-ab initio ergy of the diatomic molecule.The diabaitc PESs accurately reproduce adiabatic en-ergies,derivative coupling,and energy gradient information,thereby providing a high-fideli-ty description of the CI between the two lowest electronic states.Quantum dynamical calcu-lations have revealed significant non-adiabatic effects in the Li+Li_(2)reaction. 展开更多
关键词 Diabatic potential energy matrix Conical intersection Fundamental invariant neural network Non-adiabatic effect
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Prediction of Hot Deformation Behavior of 7Mo Super Austenitic Stainless Steel Based on Back Propagation Neural Network
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作者 WANG Fan WANG Xitao +1 位作者 XU Shiguang HE Jinshan 《材料导报》 EI CAS CSCD 北大核心 2024年第17期165-171,共7页
The hot compression tests of 7Mo super austenitic stainless(SASS)were conducted to obtain flow curves at the temperature of 1000-1200℃and strain rate of 0.001 s^(-1)to 1 s^(-1).To predict the non-linear hot deformati... The hot compression tests of 7Mo super austenitic stainless(SASS)were conducted to obtain flow curves at the temperature of 1000-1200℃and strain rate of 0.001 s^(-1)to 1 s^(-1).To predict the non-linear hot deformation behaviors of the steel,back propagation-artificial neural network(BP-ANN)with 16×8×8 hidden layer neurons was proposed.The predictability of the ANN model is evaluated according to the distribution of mean absolute error(MAE)and relative error.The relative error of 85%data for the BP-ANN model is among±5%while only 42.5%data predicted by the Arrhenius constitutive equation is in this range.Especially,at high strain rate and low temperature,the MAE of the ANN model is 2.49%,which has decreases for 18.78%,compared with conventional Arrhenius constitutive equation. 展开更多
关键词 7Mo super austenitic stainless steel hot deformation behavior flow stress BP-ANN Arrhenius constitutive equation
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Antecedents and performance consequences of governance structures in R&D alliances 被引量:1
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作者 林艺馨 荷世平 吴学良 《Journal of Southeast University(English Edition)》 EI CAS 2012年第3期360-366,共7页
Traditionally governance structures are classified into "hierarchy or market" or "equity or non-equity." However,such classifications may not be effective in characterizing all governance structures of research an... Traditionally governance structures are classified into "hierarchy or market" or "equity or non-equity." However,such classifications may not be effective in characterizing all governance structures of research and development(R D) alliances.Therefore,the first objective of this study is to investigate why there exist different organizational governance structures in managing R D alliances;the second objective of this study is to give strategic advice in choosing appropriate forms with respect to various characteristics of R D alliances.Through the theoretical lens that integrate both transaction cost economics(TCE) and the resource-based view(RBV),a model that focuses on six major factors is developed for determining governance structure choices,namely,technological uncertainty,cultural difference,asset specificity,technology complementarity,appropriability of the individual firm's know-how,and trust.An R D alliance with higher technological uncertainty,larger cultural differences,and greater concerns for protecting an individual's know-how is more likely to adopt non-integrated alliances as the governing structure.An R D alliance with a higher degree of asset-specificity,greater technology complementarity and greater trust among partnering organizations is more likely to adopt integrated alliances as the governing structure;an R D alliance in the face of lower technological uncertainty will tend to adopt integrated alliances.The more aligned the choice of the governance structure with its determinants,the better the R D alliance will perform,and vice versa. 展开更多
关键词 organizational governance structure organizational control resource-based review transaction cost economics R& D alliance
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Comparison of Benefits from Different Planting Models of Ningza No.21
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作者 浦惠明 龙卫华 +2 位作者 刘雪基 胡茂龙 高建芹 《Agricultural Science & Technology》 CAS 2014年第10期1781-1788,1804,共9页
Ningza No.21, a new hybrid rapeseed cultivar, was used as the test mate-rial in this study. The common planting models in large-scale production (3 trans-planting models and 2 direct-seeding models) were adopted. Ba... Ningza No.21, a new hybrid rapeseed cultivar, was used as the test mate-rial in this study. The common planting models in large-scale production (3 trans-planting models and 2 direct-seeding models) were adopted. Based on the high-yield cultivation, the yield and economic benefits of different planting models were investi-gated. ln addition, the labor costs, agricultural production materials costs and agri-cultural machinery costs of different planting model were analyzed to explore the low-costs and high-economic benefits planting model. The results showed the yields of the 5 planting models were al relatively high with average yield of 3 282.30 kg/hm2, ranging from 2 899.50 to 3 642.00 kg/hm2. Although the average yield and output value of transplanting models were higher than that of direct-seedling models by 429.25 kg/hm2 and 2 189.18 yuan/hm2 respectively, the production costs of trans-planting models were higher than that of direct-seedling model by 2 098.81 yuan/hm2 and the economic benefits were basical y equal. Among the costs of rapeseed pro-duction, the labor costs accounted for more than 60%. ln the labor costs, the har-vesting labor costs represented about 50%. Therefore, under current production con-ditions, the direct seeding and mechanized harvesting should be adopted in the rapeseed production to reduce production costs and improve economic benefits. 展开更多
关键词 RAPESEED Transplanting cultivation Direct-seeding cultivation Production costs Economic benefits
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Intelligent method to develop constitutive relationship of Ti-6Al-2Zr-1Mo-1V alloy 被引量:1
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作者 孙宇 曾卫东 +2 位作者 赵永庆 韩远飞 马雄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第6期1457-1461,共5页
The isothermal compression tests were carried out in the Thermecmastor-Z thermo-simulator at temperatures of 800, 850, 900, 950, 1000 and 1050 ℃ and the strain rates of 0.01, 0.1, 1 and 10 s-1. The influence of defor... The isothermal compression tests were carried out in the Thermecmastor-Z thermo-simulator at temperatures of 800, 850, 900, 950, 1000 and 1050 ℃ and the strain rates of 0.01, 0.1, 1 and 10 s-1. The influence of deformation temperature and strain rate on the flow stress of Ti-6Al-2Zr-IMo-IV alloy was studied. Based on the experimental data sets, the high temperature deformation behavior of Ti-6A1-2Zr-IMo-IV alloy was presented using the intelligent method of artificial neural network (ANN). The results indicate that the predicted flow stress values by ANN model is quite consistent with the experimental results, which implies that the artificial neural network is an effective tool for studying the hot deformation behavior of the present alloy. In addition, the development of graphical user interface is implemented using Visual Basic programming language. 展开更多
关键词 Ti-6A1-2Zr-1Mo-IV alloy artificial neural network constitutive relationship deformation behavior
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Hot deformation behavior and processing maps of Mg-Zn-Cu-Zr magnesium alloy 被引量:7
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作者 余晖 于化顺 +2 位作者 Young-min KIM Bong-sun YOU 闵光辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期756-764,共9页
The deformation behaviors of a new quaternary Mg-6Zn-1.5Cu-0.5Zr alloy at temperatures of 523-673 K and strain rates of 0.001-1 s-1 were studied by compressive tests using a Gleeble 3800 thermal-simulator.The results ... The deformation behaviors of a new quaternary Mg-6Zn-1.5Cu-0.5Zr alloy at temperatures of 523-673 K and strain rates of 0.001-1 s-1 were studied by compressive tests using a Gleeble 3800 thermal-simulator.The results show that the flow stress increases as the deformation temperature decreases or as the strain rate increases.A strain-dependent constitutive equation and a feed-forward back-propagation artificial neural network were used to predict flow stress,which showed good agreement with experimental data.The processing map suggests that the domains of 643-673 K and 0.001-0.01 s-1 are corresponded to optimum conditions for hot working of the T4-treated Mg-6Zn-1.5Cu-0.5Zr alloy. 展开更多
关键词 Mg alloy Cu addition flow stress deformation behavior constitutive equation artificial neural network processing map
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Application of Artificial Neural Network to Battlefield Target Classification
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作者 李芳 张中民 李科杰 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期201-204,共4页
To study the capacity of artificial neural network (ANN) applying to battlefield target classification and result of classification, according to the characteristics of battlefield target acoustic and seismic sign... To study the capacity of artificial neural network (ANN) applying to battlefield target classification and result of classification, according to the characteristics of battlefield target acoustic and seismic signals, an on the spot experiment was carried out to derive acoustic and seismic signals of a tank and jeep by special experiment system. Experiment data processed by fast Fourier transform(FFT) were used to train the ANN to distinguish the two battlefield targets. The ANN classifier was performed by the special program based on the modified back propagation (BP) algorithm. The ANN classifier has high correct identification rates for acoustic and seismic signals of battlefield targets, and is suitable for the classification of battlefield targets. The modified BP algorithm eliminates oscillations and local minimum of the standard BP algorithm, and enhances the convergence rate of the ANN. 展开更多
关键词 artificial neural network sample data CLASSIFIER TRAINING
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汉简《脉书》与帛书《阴阳十一脉灸经》互校三则
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作者 吕志峰 《中国文字研究》 CSSCI 2015年第1期97-99,共3页
本文将张家山汉简《脉书》与马王堆帛书《阴阳十一脉灸经》(甲、乙本)对读,解决其中存在的一些疑难字词问题。
关键词 《脉书》 《阴阳十一脉灸经》(甲、乙本) 互校
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Pedigree and Trait Analysis of Soybean Varieties Registered in Henan Province
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作者 王树峰 卢为国 李卫东 《Agricultural Science & Technology》 CAS 2015年第11期2471-2475,共5页
To elucidate the genetic relationship of the soybean varieties registered in Henan province, we analyzed the pedigrees, the major agronomic traits, and the eco- nomic traits of 74 soybean varieties registered in Henan... To elucidate the genetic relationship of the soybean varieties registered in Henan province, we analyzed the pedigrees, the major agronomic traits, and the eco- nomic traits of 74 soybean varieties registered in Henan province from 1985 to 2012, with reference to experience and technologies beneficial to breeding. The resuits indicated that these varieties originated from 113 parents, and positive correla- tion between the yield and the number of original parents was significant. In the major agronomic traits, the growth stage was about 106 days with relatively small variation, while the final height varied largely among these varieties. Among the fac- tore affecting the final yield, the pod number per plant exhibited an increasing trend, while the variation of 100-grain weight was relatively small. More than 50% of the 113 original parents came from Henan Province and its neighbor provinces, and the genetic relationship among the registered varieties was too close. The rational criteria of yield components of soybean varieties in Henan Province should be as fol- lows: the pod number per plant was about 48. 6, with 100-grain weight ranging from 17.55 g to 21.80 g. 展开更多
关键词 SOYBEAN PEDIGREE Source of parent Agronomic characters Economic characters Henan Province
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Regional Difference in Social Capital and Its Impact on Regional Economic Growth in China 被引量:14
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作者 PAN Fenghua HE Canfei 《Chinese Geographical Science》 SCIE CSCD 2010年第5期442-449,共8页
Social capital has played an increasingly important role in regional development.China is a country with high stocks of social capital.Using several different indicators of social capital,this study tries to research ... Social capital has played an increasingly important role in regional development.China is a country with high stocks of social capital.Using several different indicators of social capital,this study tries to research the regional disparities in social capital and the influence of social capital on economic growth of China in 1978-2004.Measuring social capital with indicators of associations,charities and blood donation rates,this study finds significant regional disparities in social capital at provincial level in China.Those indicators for social capital are highly correlated with regional economic performance.Statistical analysis shows that social capital has a significant and positive effect on a long-term provincial economic growth.This relationship exists after controlling policy,macro location factors,and per capita GDP in the initial year.The empirical findings indicate that institutions,culture and social relations are critical for regional development in China.Therefore,the creation and support of social capital should be paid more attention to when making regional policy. 展开更多
关键词 social capital TRUST economic growth transaction cost
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电力市场中计算输电电价的一种新方法 被引量:28
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作者 任震 吴国玥 黄雯莹 《中国电机工程学报》 EI CSCD 北大核心 2003年第1期37-40,170,共5页
该文基于边际成本理论,提出了一种计算输电电价的新方法,在保留边际成本定价中的经济信息的同时,综合考虑了无功电价,又考虑了电网的年收支平衡,最后,通过潮流跟踪法,确定有功、无功电价及固定成本在各个用户间的分配,使定价模型更加合... 该文基于边际成本理论,提出了一种计算输电电价的新方法,在保留边际成本定价中的经济信息的同时,综合考虑了无功电价,又考虑了电网的年收支平衡,最后,通过潮流跟踪法,确定有功、无功电价及固定成本在各个用户间的分配,使定价模型更加合理、完善。经IEEE6节点系统算例证明,该文所提的模型和算法是正确而有效的,具有重要的理论意义和工程实际价值,特别是对于在厂网分开后电网建设以及维护电网稳定的资金筹措有相当的指导价值。 展开更多
关键词 电网 无功功率 边际成本理论 潮流计算 电力市场 输电电价
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《佛本行集经》词语考辨 被引量:1
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作者 杨会永 《西南交通大学学报(社会科学版)》 CSSCI 2011年第3期7-10,共4页
《佛本行集经》是本缘部佛经中规模较大的佛经之一,语言通俗易懂,保留了当时大量的口语词汇,但这类词语释义多为《汉语大词典》所误释或失收。对《佛本行集经》中"狎习"等六个词语进行考辨,可知"狎习"具有"亲... 《佛本行集经》是本缘部佛经中规模较大的佛经之一,语言通俗易懂,保留了当时大量的口语词汇,但这类词语释义多为《汉语大词典》所误释或失收。对《佛本行集经》中"狎习"等六个词语进行考辨,可知"狎习"具有"亲近"义,"愚迷"有"愚蠢、愚笨、愚昧"义,"白净"为"洁白"义,"皎洁"犹言"洁白",《汉语大词典》释义不当;而"空闲"的"寂静,安静"义,则为《汉语大词典》失收;"别"为一特殊构词词尾,可解释为"每一",《汉语大词典》解释不确,应作修正。 展开更多
关键词 佛经 《佛本行集经》 本缘部佛经 《汉语大词典》
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External Landscape Design of Affordable Housing in Yuxing Homeland of Shanghai City
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作者 张波 陈长虹 《Journal of Landscape Research》 2010年第2期11-15,共5页
Approaches of external landscape design for affordable housing were discussed through analyzing the landscape designs of Yuxing Homeland in Shanghai City. By adopting simple landscape elements, following the design pr... Approaches of external landscape design for affordable housing were discussed through analyzing the landscape designs of Yuxing Homeland in Shanghai City. By adopting simple landscape elements, following the design principle of 'natural, simple and comfortable', proceeding from the overall concept, a space for neighbors’ communication with pleasant environment and outstanding functions was created, a harmonious living environment was built, and the optimal landscape benefits were obtained. 展开更多
关键词 Low cost Affordable housing Comfortable Landscape design
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Granular cell tumor of the common bile duct: A Japanese case 被引量:2
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作者 Junko Saito Michiko Kitagawa +5 位作者 Hiroshi Kusanagi Nobuyasu Kano Eiji Ishii So Nakaji Nobuto Hirata Kazuei Hoshi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第43期6324-6327,共4页
Granular cell tumor (GCT) of the biliary system is rare. It is reported that it occurs more commonly in young black women. We report here our seldom experience of a Japanese case in whom icterus was found as a first s... Granular cell tumor (GCT) of the biliary system is rare. It is reported that it occurs more commonly in young black women. We report here our seldom experience of a Japanese case in whom icterus was found as a first symptom just after a caesarean operation. A 36-year-old Japanese woman developed icterus after delivery by the Caesarean operation. A surgical operation was performed without can deny that there was a tumor-related change in a bile duct as a result of examination for various images. As a result of pathological evaluation, GCT was diagnosed. By the preoperative organization biomicroscopy result, it was not able to be attachd a right diagnosis. It was thought that this tumor, although rare, should be considered as one of the causes of biliary stenosis in the younger population. 展开更多
关键词 JAPANESE Granular cell tumor Common bile duct ICTERUS Endoscopic retrograde cholangiopancreatography
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石膏药性功效辨析 被引量:16
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作者 张晓乐 吕冠华 《实用中医内科杂志》 2018年第8期1-4,共4页
石膏乃"泻热之圣药",始载《神农本草经》,辛、微寒,《名医别录》改为辛甘、大寒,《中药学》教材及《中国药典》也标为"大寒"。石膏辛甘后世无异议,大寒分歧较多。石膏本非大寒,乃清而和缓的微寒之性,寒凉之性虽不... 石膏乃"泻热之圣药",始载《神农本草经》,辛、微寒,《名医别录》改为辛甘、大寒,《中药学》教材及《中国药典》也标为"大寒"。石膏辛甘后世无异议,大寒分歧较多。石膏本非大寒,乃清而和缓的微寒之性,寒凉之性虽不及黄连、黄柏、龙胆草等苦寒之品,清热能力远高于诸药;张仲景17首方剂用石膏,白虎汤因何重用石膏,微寒何能胜任阳明大热?石膏虽为微寒但质重气轻味辛,质重能坠热下趋,气轻可透热外出,味辛则横通郁结,热乃散消于无形之中,配知母苦寒增强清热之力;微寒亦是张锡纯用石膏之基础,治愈例证数以千计,少则三两,多则七八两,甚则达数斤,患愈之后,饮食有加,毫无寒胃之弊;无论经典文献或医家悬壶,均可证石膏"微寒"而并非"大寒",可放胆运用。石膏治烦乃取寒凉能清,质重能降,辛能散郁之性;大渴必为邪热深伤津重,胃为水谷之海、营卫之源,人参补中益气,鼓动水谷生化,方为治津伤口渴要药,仲景治阳明大渴必加人参;石膏只清邪热,切不可见表象而言石膏为止渴要药,更不可不见大渴而不投白虎于危难之中。石膏发汗,只发实热之汗,不发新受风寒之汗;内热壅盛无论有汗、无汗皆可用石膏,解肌发汗以清热,热清汗自止。石膏味辛能行、能散,微寒能清、能凉;能凉解郁热,消除热痛(因热致郁而痛)。结论:石膏质重气轻、性辛甘,微寒非大寒,能除烦不能生津止渴;解肌发汗只发身有实热之汗,不能发新受之风寒也;能凉解郁热,消除因热致郁而痛者。无论内伤外感、偏虚偏实,确有热者,投无不宜;合理配伍,对虚实并见、寒热错杂或因郁致热,因热致郁等证亦无不宜,即使大剂量运用亦无寒凉伤中之弊。正如王焘所言"石膏无毒有大益,乃养命上药,不可忽其贱而疑其寒"。 展开更多
关键词 石膏 神农本草经 名医别录 伤寒论 张仲景 四气五味 升降浮沉 微寒 大寒 生津止渴 解肌发汗 清热止痛
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Environmental damage costs from fossil electricity generation in China, 2000~2003 被引量:2
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作者 ZHANG Qing-yu WEI Yu-mei +1 位作者 CHEN Ying-xu GUO Hui 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第11期1816-1825,共10页
Electricity consumption increases rapidly with the rapid development of China. The environmental damage costs of electricity generation are very important for both policy analysis and the proper management of the envi... Electricity consumption increases rapidly with the rapid development of China. The environmental damage costs of electricity generation are very important for both policy analysis and the proper management of the environment. A method was developed in this work to estimate gross environmental damage costs according to emission inventory and environmental cost factors, and to extend the costs from provincial to national level with population density. In this paper, sulfur dioxide (SO2), nitrogen oxides (NOx), particulate matter less than 10 μm in diameter (PM10), and carbon dioxide (CO2) from fossil fired power plants over 6000 kW were selected as index pollutants to quantify the environmental costs of damages on human health and global warming. With the new developed method, environmental damage costs, caused by 3 types of fired power plants in 30 provinces and 6 economic sectors during the years 2000 to 2003, were evaluated and analyzed. It can be seen that the calculated total national environmental damage costs of electricity have rapidly increased from 94930.87×106 USD in 2000 to about 141041.39×106 USD in 2003, with an average annual growth rate of 14.11%. Environmental damage costs of SO2, NOx, PM10, and CO2 are 69475.69×106, 30079.29×106, 28931.84×106, and 12554.57×106 USD and account for 49.26%, 21.33%, 20.51%, and 8.90% of total environmental costs in fossil electricity generation, respectively. With regard to regional distribution, external costs caused by fossil electricity generation are mainly concentrated in the more populated and industrialized areas of China, i.e., the Eastern Central and Southeastern areas. 展开更多
关键词 Environmental damage costs Fossil electricity generation Emission inventory Uncertainty analysis
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《神农本草经》成书考 被引量:6
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作者 丁振国 张净秋 《中医药文化》 2023年第5期434-452,共19页
随着出土文献的不断问世,有关古书成书的讨论越发热烈。结合新的理论观点,借助出土与传世文献的综合分析,同时参考前人的研究成果,对《神农本草经》成书过程、文本状貌更为细密的探究成为可能。该书是以早期本草类文书为基础逐渐生成的... 随着出土文献的不断问世,有关古书成书的讨论越发热烈。结合新的理论观点,借助出土与传世文献的综合分析,同时参考前人的研究成果,对《神农本草经》成书过程、文本状貌更为细密的探究成为可能。该书是以早期本草类文书为基础逐渐生成的,这反映出早期药物学知识不断积累的过程。目前所知最早的《本草》古书出现在东汉后期,之后的魏晋南北朝300余年,本草著作蓬勃发展。其间《本草》呈现出相当复杂的局面:其一,书名众多;其二,出现同书异本、同名异书现象;其三,《本草》的整理和研究著作不断涌现。这对于《本草》作为“经”的确立、定本的确定起到了重要作用,南朝梁陶弘景整理的《本草经集注》是其中的一个重要文本。《神农本草经》的成书是一个动态累积的过程,其经典化历程展现出士人对技术类文本所持的一种尴尬态度和折衷处理方式。 展开更多
关键词 《神农本草经》 陶弘景 成书 《汉书·艺文志》 《隋书·经籍志》 书籍史
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Real-Time Face Tracking and Recognition in Video Sequence 被引量:3
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作者 徐一华 贾云得 +1 位作者 刘万春 杨聪 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期203-207,共5页
A framework of real time face tracking and recognition is presented, which integrates skin color based tracking and PCA/BPNN (principle component analysis/back propagation neural network) hybrid recognition techni... A framework of real time face tracking and recognition is presented, which integrates skin color based tracking and PCA/BPNN (principle component analysis/back propagation neural network) hybrid recognition techniques. The algorithm is able to track the human face against a complex background and also works well when temporary occlusion occurs. We also obtain a very high recognition rate by averaging a number of samples over a long image sequence. The proposed approach has been successfully tested by many experiments, and can operate at 20 frames/s on an 800 MHz PC. 展开更多
关键词 face tracking pattern recognition skin color based eigenface/PCA artificial neural network
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A PATH-DEPENDENT MODEL OF INVESTMENT AND EMPLOYMENT FLOW IN A LARGE ECONOMY IN A PROCESS OF INTEGRATION 被引量:2
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作者 LIUAn-guo YANGKai-zhong 《Chinese Geographical Science》 SCIE CSCD 2004年第4期289-295,共7页
This paper meant to analyze the spatial evolution of a large country in its process of integration with the world economy in general, and, to look into the possible effect of China′s accession into WTO on the future ... This paper meant to analyze the spatial evolution of a large country in its process of integration with the world economy in general, and, to look into the possible effect of China′s accession into WTO on the future development of its spatial economy in particular. Through an approach of increasing returns, external economy, product differentiation and path-dependence, with foreign trade costs incurred by different regions within the large country discriminated, a model of investment and employment flow is developed as a simulation of a large country′s process of integration with the world economy. The modeling indicates that in the process of integration, as there exist differences in foreign trade costs among different regions within the large country, either the spatial economy of the country deviates from its symmetric structure in autarky and falls into a core-periphery relationship, or the effect of industrial agglomeration is reinforced, amplified and locked in, if the agglomeration had been started. The economic gap on either the aggregate or structural basis between different regions within the large country will increase rapidly as the integration proceeds. 展开更多
关键词 increasing returns pecuniary externality trade cost INVESTMENT EMPLOYMENT
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