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Modeling of multiphase flow in low permeability porous media:Effect of wettability and pore structure properties
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作者 Xiangjie Qin Yuxuan Xia +3 位作者 Juncheng Qiao Jiaheng Chen Jianhui Zeng Jianchao Cai 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1127-1139,共13页
Multiphase flow in low permeability porous media is involved in numerous energy and environmental applications.However,a complete description of this process is challenging due to the limited modeling scale and the ef... Multiphase flow in low permeability porous media is involved in numerous energy and environmental applications.However,a complete description of this process is challenging due to the limited modeling scale and the effects of complex pore structures and wettability.To address this issue,based on the digital rock of low permeability sandstone,a direct numerical simulation is performed considering the interphase drag and boundary slip to clarify the microscopic water-oil displacement process.In addition,a dual-porosity pore network model(PNM)is constructed to obtain the water-oil relative permeability of the sample.The displacement efficiency as a recovery process is assessed under different wetting and pore structure properties.Results show that microscopic displacement mechanisms explain the corresponding macroscopic relative permeability.The injected water breaks through the outlet earlier with a large mass flow,while thick oil films exist in rough hydrophobic surfaces and poorly connected pores.The variation of water-oil relative permeability is significant,and residual oil saturation is high in the oil-wet system.The flooding is extensive,and the residual oil is trapped in complex pore networks for hydrophilic pore surfaces;thus,water relative permeability is lower in the water-wet system.While the displacement efficiency is the worst in mixed-wetting systems for poor water connectivity.Microporosity negatively correlates with invading oil volume fraction due to strong capillary resistance,and a large microporosity corresponds to low residual oil saturation.This work provides insights into the water-oil flow from different modeling perspectives and helps to optimize the development plan for enhanced recovery. 展开更多
关键词 Low permeability porous media Water-oil flow WETTABILITY Pore structures dual porosity pore network model(PNM) Free surface model
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Dual Instinct and Structural Theories: DSM-5-TR
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作者 Lawrence Greenman 《Open Journal of Psychiatry》 2024年第4期374-379,共6页
The genetic based Dual Instinct Theory is determined by evolutionary history. Aggression is required for survival and sex for propagation of species. Aggressive and sexual drive derivatives with their corresponding de... The genetic based Dual Instinct Theory is determined by evolutionary history. Aggression is required for survival and sex for propagation of species. Aggressive and sexual drive derivatives with their corresponding defence mechanisms are combined with biologically based stages of infant/child development and the functional entity of Structural Theory. This model of human nature is the applied to the diagnostic categories of DSM-5-TR. Objectives: To follow the innate Dual Instinct Theory from life to death and through Artificial Intelligence;connect it with biological stages of development of the Structural Theory and illustrate its manifestations in DSM-5-TR classifications. Method: Review of selected published literature. Applying the principle of focus and cognition of informed clinical observation of innate drive derivatives in conjunction with The Structural Theory. Both theories are functional entities with no structures involved. Sigmund Freud’s biologically based stages of development;oral, anal, genital pubic, adult, and geriatric along with a variety of unconscious, automatic, and persistent defense mechanisms are selectively folded into diagnosis listed in the manual. 展开更多
关键词 dual Instincts structural Theory Stages of Development Drive Derivatives Mechanisms of Defense
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High performance carrier stored trench bipolar transistor with dual shielding structure
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作者 张金平 邓浩楠 +2 位作者 朱镕镕 李泽宏 张波 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期576-582,共7页
We propose a novel high performance carrier stored trench bipolar transistor(CSTBT)with dual shielding structure(DSS-CSTBT).The proposed DSS-CSTBT features a double trench structure with different trench profiles in t... We propose a novel high performance carrier stored trench bipolar transistor(CSTBT)with dual shielding structure(DSS-CSTBT).The proposed DSS-CSTBT features a double trench structure with different trench profiles in the surface,in which a shallow gate trench is shielded by a deep emitter trench and a thick oxide layer under it.Compared with the conventional CSTBT(con-CSTBT),the proposed DSS-CSTBT not only alleviates the negative impact of the shallow gate trench and highly doped CS layer on the breakdown voltage(BV),but also well reduces the gate-collector capacitance CGC,gate charge Q_(G),and turn-off loss E_(OFF)of the device.Furthermore,lower turn-on loss E_(ON)and gate drive loss E_(DR)are also obtained.Simulation results show that with the same CS layer doping concentration N_(CS)=1.5×10^(16)cm^(-3),the BV increases from 1312 V of the con-CSTBT to 1423 V of the proposed DSS-CSTBT with oxide layer thickness under gate(T_(og2))of 1μm.Moreover,compared with the con-CSTBT,the C_(GC)at V_(CE)of 25 V and miller plateau charge(Q_(GC))for the proposed DSS-CSTBT with T_(og2)of 1μm are reduced by 79.4%and 74.3%,respectively.With the VGEincreases from 0 V to 15 V,the total QGfor the proposed DSS-CSTBT with T_(og2)of 1μm is reduced by 49.5%.As a result,at the same on-state voltage drop(V_(CEON))of 1.55 V,the E_(ON)and E_(OFF)are reduced from 20.3 mJ/cm^(2)and 19.3 mJ/cm^(2)for the con-CSTBT to8.2 mJ/cm^(2)and 9.7 mJ/cm^(2)for the proposed DSS-CSTBT with T_(og2)of 1μm,respectively.The proposed DSS-CSTBT not only significantly improves the trade-off relationship between the V_(CEON)and E_(OFF)but also greatly reduces the E_(ON). 展开更多
关键词 carrier stored trench bipolar transistor(CSTBT) dual shielding structure gate-collector capacitance power loss
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Research Progress of Soil Loss in Karst Areas under the Dual Structure of Southwest China 被引量:1
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作者 安吉平 王济 +2 位作者 蔡雄飞 段志斌 颜蒙蒙 《Agricultural Science & Technology》 CAS 2017年第8期1452-1458,共7页
The research progress of soil loss under the dual structure of southwest karst is systematically studied. The results show that the research of the soil erosion in karst mountainous area started late, and the basic re... The research progress of soil loss under the dual structure of southwest karst is systematically studied. The results show that the research of the soil erosion in karst mountainous area started late, and the basic research is lagging. Most of the existing research results focus on the present situation, causes and control measures of surface erosion. The view of underground soil loss in the context of karst diploid structure has been recognized by most scholars. However, limited to the research methods and the lack of observational data, the way of underground soil loss, the amount of loss and its harm are still unclear. Therefore, seeking the necessary technical means to carry out the necessary field observation from the way and process of loss is the focus of the study of soil loss under karst structure in the future. 展开更多
关键词 KARST dual structure Surface soil erosion Underground soil loss
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Analysis of Responses of Floating Dual Pontoon Structure 被引量:2
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作者 翁文凯 周宗仁 《China Ocean Engineering》 SCIE EI 2007年第1期91-104,共14页
A numerical model is developed by use of the boundary integral equation method to investigate the responses of a two-dimensional floating structure. The structure under consideration consisting of two pontoons, is con... A numerical model is developed by use of the boundary integral equation method to investigate the responses of a two-dimensional floating structure. The structure under consideration consisting of two pontoons, is connected by a rigid framework, and linked to the sea floor by a mooring system. The theoretical conception is based on potential theory with hnear external forces, and applied to an arbitrarily shaped body and water depth. The discussion includes the influence of draft and space between pontoons on the responses of the floating structure. Finally, the validity of the method is adequately verified by experimental results. 展开更多
关键词 boundary element method floating structure dual pontoon
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The Chinese Urban-rural Dual Economic Structure Model and Analysis 被引量:2
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作者 Xiuchuan XU Shengping SHI Qinghua HUANG 《Asian Agricultural Research》 2014年第1期18-23,共6页
Based on the characteristics of urban-rural dual economic structure in China,we build a dynamic endogenous urban-rural dual economic model closely linked to China's reality,and carry out mathematical economics ana... Based on the characteristics of urban-rural dual economic structure in China,we build a dynamic endogenous urban-rural dual economic model closely linked to China's reality,and carry out mathematical economics analysis of optimized conditions for urban and rural sectors. The main results show that:(i) The labor growth rate of urban-rural sectors must be greater than the time discount rate,or else there would be a vicious cycle of diminishing returns in the sectors;(ii) The accumulation rate of physical capital and human capital of urban-rural sectors,and the rate of technological progress,need to be greater than the corresponding depreciation rate plus the time discount rate,otherwise there would be a vicious cycle of diminishing returns in the sectors;(iii) The low accumulation rate in the rural sector,and the occurrence of labor outflow,human capital loss and lack of investment,will expand income gap between urban and rural areas,which is a reason for solidification of urban-rural dual economic structure. 展开更多
关键词 Urban-rural dual ECONOMIC structure DYNAMIC optimi
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Phase composition, transition and structure stability of functionally graded cemented carbide with dual phase structure 被引量:2
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作者 张立 陈述 +3 位作者 熊湘君 贺跃辉 黄伯云 张传福 《Journal of Central South University of Technology》 EI 2007年第2期149-152,共4页
The phase composition, phase transition and phase structure transformation of the wire-cut section of functionally graded WC-Co cemented carbide with dual phase structure were investigated by XRD phase analysis. It is... The phase composition, phase transition and phase structure transformation of the wire-cut section of functionally graded WC-Co cemented carbide with dual phase structure were investigated by XRD phase analysis. It is shown that the composition of η phase in the core zone is Co_3W_3C (M_6 C type). The structure of cobalt based solid solution binder phase is fcc type. At the cooling stage of the sintering process, the phase transition of η phase, i.e. M_6C→M_12C and the martensitic phase transition of the cobalt based solid solution binder phase, i.e. fcc→hcp are suppressed, which facilitates the strengthening of the alloy. Because the instantaneous temperature of the discharge channel is as high as 10 000 ℃ during the wire cutting process, the processed surface is oxidized. Nevertheless, the oxide layer thickness is in micro grade. In the oxide film, η phase is decomposed into W_2C and CoO, and cobalt based solid solution binder is selectively oxidized, while WC remains stable due to the existence of carbon containing liquid organic cutting medium. 展开更多
关键词 cemented carbide dual phase structure functionally graded material phase identification fracture toughness testing
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Science Letters:Dual structure of composite right/left-handed transmission line 被引量:1
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作者 HU Xin ZHANG Pu HE Sailing 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第10期1777-1780,共4页
A dual structure of composite right/left handed (CRLH) transmission line (TL) is analyzed in which an inductance LR is in parallel with a capacitance CL and a shunt capacitance CR is in series with an inductance LL. B... A dual structure of composite right/left handed (CRLH) transmission line (TL) is analyzed in which an inductance LR is in parallel with a capacitance CL and a shunt capacitance CR is in series with an inductance LL. Both the distributed and lumped cases are considered. The dispersion diagram and transmission properties of the dual CRLH TL are given and compared with those of a standard CRLH TL. Contrary to the frequency response of a standard CRLH TL, a dual CRLH TL has a left-handed (negative phase shift) band at higher frequencies and a right-handed (positive phase shift) band at lower frequencies. A novel dual-band balun is presented as an application. 展开更多
关键词 dual structure Composite fight/left handed transmission line (CRLH TL) dual band balun
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Kinematic Structure of a Heavy Rain Event from Dual-Doppler Radar Observations 被引量:14
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作者 邵爱梅 邱崇践 刘黎平 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第4期609-616,共8页
The detailed kinematic structure of a heavy rain event that occurred in the middle reaches of the Yangtze River was investigated using dual-Doppler radar observation. A variational analysis method was developed to obt... The detailed kinematic structure of a heavy rain event that occurred in the middle reaches of the Yangtze River was investigated using dual-Doppler radar observation. A variational analysis method was developed to obtain the three-dimensional wind fields. Before the analysis, a data preprocessing procedure was carried out, in which the temporal variation with the scanning time interval and the effect of the earth curvature on the data position were taken into account. The analysis shows that a shear line in the lower and middle levels played an important role in the rainfall event. The precipitation fell mainly on the south end of the shear line where southerly flow prevailed and convergence and updraft were obvious. With the movement and decay of the shear line, the precipitation moved and decayed correspondingly. 展开更多
关键词 heavy rain mesoscale structure dual-Doppler variational method
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TEMPERING RESPONSE OF A DEFORMED LOW CARBON DUAL PHASE STRUCTURE
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作者 JIN Man JIANG Zhonghao +2 位作者 NAN Shenghui HU Jiandong LIAN jianshe(Jilin University of Technology,Changchun,China)(Manuscript received 8 February 1995)Correspondent:LI Geping,(Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110015,China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1995年第2期79-83,共5页
The low carbon dual phase structure was cold de formed first,then was tempered at 200 to 600℃.The variation in strength and ductility during tempering of the steel was investigated.It was found that a fter the de for... The low carbon dual phase structure was cold de formed first,then was tempered at 200 to 600℃.The variation in strength and ductility during tempering of the steel was investigated.It was found that a fter the de formed dual phase structure was tempered at 200 to 600℃, with the increase in the tempering temperature the tensile strength decreases rapidly;the lotal elongation remains constant at 200 to 500℃ but began to rise dramatically at a critical temperature between 500 and 600℃.However,when the non-deformed dual phase structure was tempered at the same temperature range,the tensile strength decreases and the total elongation increases continuously with the increase of temperature.It was demonstrated from TEM analysis that precipitating carbides density along the boundaries ofmartensite lath and the recrystallized grains are responsible for the tempering response ofthe de formed dual phase structure. 展开更多
关键词 de formed dual phase structure tensile property TEMPERING
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Dual Characteristic Pairs in Generalized Complex Structures
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作者 YIN Yan-bin LIU Ling LIU Hua-qiao 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第2期196-201,共6页
This paper presents the relations between spinors and dual characteristic pairs, and gives a way to get the dual characteristic pairs of Dirac structure associated to a generalized complex structure.
关键词 Dirac structure generalized complex structure dual characteristic pair
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Study on Factors Influencing Urban-rural Dual Economic Structure of Chongqing Based on the State Space Variable Parameter Method
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作者 Xiuchuan XU Yuqing WANG Xiang HE 《Asian Agricultural Research》 2013年第11期9-13,共5页
Firstly,this paper reviews and analyzes historic background of urban-rural integration of Chongqing,and the evolution and trend of urban and rural dual economic structure.On the basis of previous researches,it selects... Firstly,this paper reviews and analyzes historic background of urban-rural integration of Chongqing,and the evolution and trend of urban and rural dual economic structure.On the basis of previous researches,it selects factors and variables influencing urban and rural dual economic structure,and establishes an econometric model.By state space Kalman filtering method,it analyzes dynamic influence of factors upon urban-rural dual economic intensity.According to empirical conclusion,it puts forward corresponding policy recommendations for promoting integrated urban and rural economic development of Chongqing. 展开更多
关键词 URBAN and RURAL dual ECONOMIC structure State SPAC
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Bis(1-(4-(dimethylamino)benzylidene)-4-phenylthiose micarbaznato)palladium(Ⅱ):Synthesis,Crystal Structure and Its Dual Fluorescence Property
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作者 徐勤娟 林丽榕 +2 位作者 孙頔 黄荣彬 郑兰荪 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第8期1169-1174,共6页
The title compound bis(1-(4-(dimethylamino)benzylidene)-4-phenylthiosemicar-bazato)-palladium(Ⅱ)(PdL2) was obtained by reacting 1-(4-(dimethylamino)benzylidene)-4-phenyl-thiosemicarbazide with dichloro... The title compound bis(1-(4-(dimethylamino)benzylidene)-4-phenylthiosemicar-bazato)-palladium(Ⅱ)(PdL2) was obtained by reacting 1-(4-(dimethylamino)benzylidene)-4-phenyl-thiosemicarbazide with dichlorobis(benzonitrile)palladium(Ⅱ) in methanol,and its structure was characterized by single-crystal X-ray diffraction.The crystal of PdL2 was obtained in dimethyl-formamide(DMF) solvent with solvent molecules involved in the cell and crystallizes in the monoclinic system,space group C2 with a = 18.485(15),b = 7.090(5),c = 17.595(11) ,β = 121.21(3)o,V = 1972(2) 3,Z = 2,Mr = 847.40,Dc = 1.427 g/cm3,μ = 0.624 mm-1,F(000) = 880,R = 0.0607 and wR = 0.1358.The Pd atom adopts a distorted square planar coordination geometry with two Pd-N and two Pd-S bonds.The ligand loses a proton from its tautomeric thiol form and coordinates to the Pd atom via mercapto sulfur and the imine nitrogen atom,which binds to palladium as bidentate N,S-donors forming five-membered chelate rings.The complex formed hydrogen bonding interaction with solvent DMF molecules from the hydrogen of phenylamine to the oxygen of DMF and several intramolecular hydrogen bonds.Pd(Ⅱ) perturbed ligand π-π* transition and metal-to-ligand charge transfer(MLCT) transition are observed in its electronic absorption spectra.The complex exhibits intraligand 1π-π*(IL) state and MLCT state dual fluorescent emissions in organic solvent at room temperature. 展开更多
关键词 palladium(Ⅱ) complex 1-(4-(dimethylamino)benzylidene)-4-phenylthiosemicarbazide dual fluorescence crystal structure
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Application of dual structure theory on motivating safe behavior of coal mine staff
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《Journal of Coal Science & Engineering(China)》 2012年第1期73-79,共7页
Based on behavior science and direct causes analysis of serious accidents in Chinese coal mines in recent 5 years, a conclusion that unsafe behaviors of coal mine staff were the direct causes of these serious accident... Based on behavior science and direct causes analysis of serious accidents in Chinese coal mines in recent 5 years, a conclusion that unsafe behaviors of coal mine staff were the direct causes of these serious accidents was drawn, accounting for 91.3%. If staff was divided into executor and manager, percentages of the executor's and manager's unsafe behaviors in direct causes of the accidents were 69% and 54%, respectively, with executor's unsafe behavior as direct causes and manager's unsafe behavior as essential reasons after thorough analysis of these accidents. Further, on the basis of dual structure theory analysis, three new understandings, including transformation, hierarchy classification and representativeness of behavior factors were il- lustrated. Behavior factors of executors and managers in Chinese coal mines were summarized and classified by new recogni- tion. Then, dual structure theory was applied in a coal mine in Hebei Province of China; weakening unsafe behaviors and strengthening safe factors can attain the purpose of motivating safer behaviors in the coal mine. 展开更多
关键词 dual structure theory unsafe behavior new understandings application study
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Dual Structure—Economic Development Pattern of Chinese Mining Industry
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《Journal of Earth Science》 SCIE CAS CSCD 2000年第2期102-103,共2页
关键词 dual structure Economic Development Pattern of Chinese Mining Industry
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Space Topologies and Their Dual Space Topologies for Conventional Functional Space Topologies
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作者 Mahjoub A. Elamin 《Journal of Applied Mathematics and Physics》 2024年第3期778-804,共27页
In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topo... In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topological vector spaces and it is in this context that we have chosen to present this work. We are interested in the topology of its spaces and in the topologies of their dual spaces. The first part, we presented the fundamental topological properties of topological vector spaces. The second part, we studied Frechet spaces and particularly the space S(R<sup>n</sup>) of functions of class C<sup>∞ </sup>on R<sup>n</sup> which are as well as all their rapidly decreasing partial derivatives. We have also studied its dual S'(Rn</sup>) the space of tempered distributions. The last part aims to define a topological structure on an increasing union of Frechet spaces called inductive limit of Frechet spaces. We study in particular the space D(Ω) of functions of class C<sup>∞</sup> with compact supports on Ω as well as its dual D' (Ω) the space distributions over the open set Ω. 展开更多
关键词 Linear Forms dual Spaces Frechet Spaces Partial Derivatives DISTRIBUTIONS Topological structure Weak Topology Strong Topology
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Structure and Magnetic Properties of Fe-N Films Prepared by Dual Ion Beam Sputtering
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作者 诸葛兰剑 吴雪梅 +2 位作者 汤乃云 叶春兰 姚伟国 《Plasma Science and Technology》 SCIE EI CAS CSCD 2001年第6期1049-1054,共6页
Fe-N films were prepared on Si substrate by dual ion beam sputtering (DIBS). It is found that the crystal structure of the films varies from α-Fe, to ε-Fe2-3N, ε-Fe2-3N +γ-Fe4N, and finally γ'-Fe4N with the i... Fe-N films were prepared on Si substrate by dual ion beam sputtering (DIBS). It is found that the crystal structure of the films varies from α-Fe, to ε-Fe2-3N, ε-Fe2-3N +γ-Fe4N, and finally γ'-Fe4N with the increase in substrate temperature (TS). The magnetic properties of the films were investigated by a vibrating sample magnetometer (VSM). The structure of the films is insensitive to the ratios of N2/Ar in main ion source(MIS), and is mainly influenced by the substrate temperature (Ts). 展开更多
关键词 FE structure and Magnetic Properties of Fe-N Films Prepared by dual Ion Beam Sputtering
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Has Okun's Law Become Invalid in China?——Estimation of Potential GDP Growth Rates and Natural Rates of Unemployment Based on Dual Structure
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作者 邹沛江 《China Economist》 2014年第1期53-67,共15页
This paper calculates the potential GDP growth rates and the natural rates of unemployment in China using the dual decomposition of the simple Okun's law. The results show that every 1% increase in China's urban reg... This paper calculates the potential GDP growth rates and the natural rates of unemployment in China using the dual decomposition of the simple Okun's law. The results show that every 1% increase in China's urban registered unemployment rate leads to a 1.98% drop of GDP, the potential growth rate of GDP of China is about 10%, and the average natural rate of unemployment is about 3.2% in China in the past three decades. The paper finds that Olcun's law is still valid in China in the long run, but the Okun coefficient is about -3.79, overestimating the impact of the registered unemployment rate on GDP growth, and needs to be corrected based on China's dual economic structure. 展开更多
关键词 Okun's Law dual structure natural rate
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From Shanghai empty-nesters problem of looking of urban and rural dual structure
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作者 Zhang YiRan 《International English Education Research》 2015年第8期60-61,共2页
With the continuous development of political, economic,social, empty nesters and more problems, it is not a simple personal issues, has become urgent to break the social proposition.This paper intr~,duces the concepts... With the continuous development of political, economic,social, empty nesters and more problems, it is not a simple personal issues, has become urgent to break the social proposition.This paper intr~,duces the concepts at the same time,Further analysis of the current situation empty-nesters of the problem and sort out the history of urban-rural dual structure,Finally, find information put forward some countermeasures and suggestions. 展开更多
关键词 empty nesters urban-rural dual structure research questions
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Look from the empty nester problem of urban and rural dual structure of society
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作者 Wang Hainan 《International English Education Research》 2014年第12期5-7,共3页
More and more empty nest has become a social problem that couldn't ignore. The problem of empty nester is the essence of urban and rural dual structure social changing. The emergence of empty-nesters is a serious pro... More and more empty nest has become a social problem that couldn't ignore. The problem of empty nester is the essence of urban and rural dual structure social changing. The emergence of empty-nesters is a serious problem in China's social development process, with the aging of the population increasing, urban-rural divide more and more obvious. The condition of the human society has gradually formed the rural and the division of labor and the dual structure of the city. This paper expounds the connotation, significance and characteristics of empty nest elderly, analyzes on the problems existing in current urban and rural society and the problem of empty nest elderly in the new situation puts forward the suggestions and countermeasures. 展开更多
关键词 empty nester social dual structure between urban and rural areas social welfare system the solution strategy
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