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Three-dimensional structural models,evolution and petroleum geological significances of transtensional faults in the Ziyang area,central Sichuan Basin,SW China
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作者 TIAN Fanglei GUO Tonglou +6 位作者 HE Dengfa GU Zhanyu MENG Xianwu WANG Renfu WANG Ying ZHANG Weikang LU Guo 《Petroleum Exploration and Development》 SCIE 2024年第3期604-620,共17页
With drilling and seismic data of Transtensional(strike-slip)Fault System in the Ziyang area of the central Sichuan Basin,SW China plane-section integrated structural interpretation,3-D fault framework model building,... With drilling and seismic data of Transtensional(strike-slip)Fault System in the Ziyang area of the central Sichuan Basin,SW China plane-section integrated structural interpretation,3-D fault framework model building,fault throw analyzing,and balanced profile restoration,it is pointed out that the transtensional fault system in the Ziyang 3-D seismic survey consists of the northeast-trending F_(I)19 and F_(I)20 fault zones dominated by extensional deformation,as well as 3 sets of northwest-trending en echelon normal faults experienced dextral shear deformation.Among them,the F_(I)19 and F_(I)20 fault zones cut through the Neoproterozoic to Lower Triassic Jialingjiang Formation,presenting a 3-D structure of an“S”-shaped ribbon.And before Permian and during the Early Triassic,the F_(I)19 and F_(I)20 fault zones underwent at least two periods of structural superimposition.Besides,the 3 sets of northwest-trending en echelon normal faults are composed of small normal faults arranged in pairs,with opposite dip directions and partially left-stepped arrangement.And before Permian,they had formed almost,restricting the eastward growth and propagation of the F_(I)19 fault zone.The F_(I)19 and F_(I)20 fault zones communicate multiple sets of source rocks and reservoirs from deep to shallow,and the timing of fault activity matches well with oil and gas generation peaks.If there were favorable Cambrian-Triassic sedimentary facies and reservoirs developing on the local anticlinal belts of both sides of the F_(I)19 and F_(I)20 fault zones,the major reservoirs in this area are expected to achieve breakthroughs in oil and gas exploration. 展开更多
关键词 transtensional(strike-slip)fault three-dimensional structural model structural evolution petroleum geological significance Ziyang area Sichuan Basin
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Effects of three-dimensional quality assessment nursing intervention on efficacy and disease management of patients undergoing esophageal cancer surgery
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作者 Hai-Yan Wu Jie Jin +3 位作者 Chen Chen Jing-Jing Xu Qi Jiang Dong-Mei Lu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第9期2979-2985,共7页
BACKGROUND Esophageal cancer is one of the most common malignant tumors.The three-dimensional quality structure model is a quality assessment theory that includes three dimensions:Structure,process,and results.AIM To ... BACKGROUND Esophageal cancer is one of the most common malignant tumors.The three-dimensional quality structure model is a quality assessment theory that includes three dimensions:Structure,process,and results.AIM To investigate the effects of nursing interventions with three-dimensional quality assessment on the efficacy and disease management ability of patients undergoing esophageal cancer surgery.METHODS In this prospective study,the control group received routine nursing,and the intervention group additionally received a three-dimensional quality assessment intervention based on the above routine care.Self-efficacy and patient disease management abilities were evaluated using the General Self-Efficacy Scale(GSES)and Exercise of Self-Care Agency scale,respectively.IBM SPSS Statistics for Windows,version 17.0,was used for the data processing.RESULTS This study recruited 112 patients who were assigned to the control and experi-mental groups(n=56 per group).Before the intervention,there was no significant difference in GSES scores between the two groups(P>0.05).After the inter-vention,the GSES scores of both groups increased,with the experimental group showing higher values(P<0.05).At the time of discharge and three months after discharge,the scores for positive attitudes,self-stress reduction,and total score of health promotion in the experimental group were higher than those in the control group(P<0.05).CONCLUSION The implementation of a three-dimensional quality structure model for postoperative patients with esophageal cancer can effectively improve their self-management ability and self-efficacy of postoperative patients. 展开更多
关键词 Esophageal cancer three-dimensional quality structure model SELF-EFFICACY Disease management ability
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Head Pursuit Variable Structure Guidance Law for Three-dimensional Space Interception 被引量:10
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作者 葛连正 沈毅 +1 位作者 高云峰 赵立军 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第3期247-251,共5页
This article aims to develop a head pursuit (HP) guidance law for three-dimensional hypervelocity interception, so that the effect of the perturbation induced by seeker detection can be reduced. On the basis of a no... This article aims to develop a head pursuit (HP) guidance law for three-dimensional hypervelocity interception, so that the effect of the perturbation induced by seeker detection can be reduced. On the basis of a novel HP three-dimensional guidance model, a nonlinear variable structure guidance law is presented by using Lyapunov stability theory. The guidance law positions the interceptor ahead of the target on its tlight trajectory, and the speed of the interceptor is required to be lower than that of the target, A numerical example of maneuvering ballistic target interception verifies the rightness of the guidance model and the effectiveness of the proposed method. 展开更多
关键词 head pursuit three-dimensional guidance model nonlinear variable structure Lyapunov stability theory guidance law
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Three-Dimensional Tidal Model and Its Application to Numerical Simulation of Water Quality in Coastal Waters 被引量:5
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作者 Shen Yongming , Li Yucheng and Zhao Wenqian Associate Professor, Department of Civil Engineering, Dalian University of Technology, Dalian 116023 Professor, Department of Civil Engineering, Dalian University of Technology, Dalian 116023 Professor, Department of Civil Engineering, Sichuan Union University, Chengdu 610065 《China Ocean Engineering》 SCIE EI 1994年第4期425-436,共12页
The turbulence mechanism plays an important part in the mixing process and momentum transfer of turbulence. A three-dimensional Prandtl mixing length tidal model has been developed to simulate tidal flows and water qu... The turbulence mechanism plays an important part in the mixing process and momentum transfer of turbulence. A three-dimensional Prandtl mixing length tidal model has been developed to simulate tidal flows and water quality. The eddy viscosities and diffusivities are computed from the Prandtl mixing length model. In order to model the water quality of an estuary or coastal area many interdependent processes need to be simulated. These may be conveniently separated into three main groups: transport and mixing processes, biochemical interaction of water quality variables and the utilization and re-cycling of nutrients by living matter. The model simulates full oxygen and nutrient balance, primary productivity and the transport, reaction mechanism and fate of pollutants over tidal time-scales. The model is applied to numerical simulation of tidal flows and water quality in Dalian Bay. The model has been calibrated against a limited data set of historical water quality observations and in general demonstrates excellent agreement with all available data. 展开更多
关键词 three-dimension tidal flows water quality ECOSYSTEM mixing length model coastal waters
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A Three-Dimensional Water Quality Model and Its Application to Jiaozhou Bay, China 被引量:2
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作者 张燕 孙英兰 +2 位作者 余静 袁道伟 张瑞瑾 《China Ocean Engineering》 SCIE EI 2012年第4期669-684,共16页
A three-dimensional coupled physical and water quality model was developed and applied to the Jiaozhou Bay to study water quality involving nutrients, biochemical oxygen demand, dissolved oxygen, and phytoplankton tha... A three-dimensional coupled physical and water quality model was developed and applied to the Jiaozhou Bay to study water quality involving nutrients, biochemical oxygen demand, dissolved oxygen, and phytoplankton that are closely related to eutrophication process. The physical model is a modified ECOM-si version with inclusion of flooding/draining processes over the intertidal zone. The water quality model is based on WASP5 which quantifies processes governing internal nutrients cycling, dissolved oxygen balance and phytoplankton growth. The model was used to simulate the spatial distribution and the temporal variation of water quality in the Jiaozhou Bay for the period of May 2005 to May 2006. In addition, the effect of reduction of riverine nutrients load was simulated and evaluated. The simulated results show that under the influence of nutrients discharged from river, the concentrations of nutrients and phytoplankton were higher in the northwest and northeast of the bay, and decreased from the inner bay to the outer. Affected by strong tidal mixing, the concentrations of all state variables were vertically homogeneous except in the deeper regions where a small gradient was found. Obvious seasonal variation of phytoplankton biomass was found, which exhibited two peaks in March and July, respectively. The variation of riverine waste loads had remarkable impact on nutrients concentration in coastal areas, but slightly altered the distribution in the center of the bay. 展开更多
关键词 water quality model EUTROPHICATION numerical simulation three-dimensional Jiaozhou Bay
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Framework system and research flow of uncertainty in 3D geological structure models 被引量:7
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作者 ZHU, Liangfeng ZHUANG, Zhiyi 《Mining Science and Technology》 EI CAS 2010年第2期306-311,共6页
Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling.In order to solve this problem during periods of accuracy assessment,error... Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling.In order to solve this problem during periods of accuracy assessment,error detection and dynamic correction in 3D geological structure models,we have reviewed the current situation and development trends in 3D geological modeling.The main context of uncertainty in 3D geological structure models is discussed.Major research issues and a general framework system of uncertainty in 3D geological structure models are proposed.We have described in detail the integration of development practices of 3D geological modeling systems,as well as the implementation process for uncertainty evaluation in 3D geological structure models.This study has laid the basis to build theoretical and methodological systems for accuracy assessment and error correction in 3D geological models and can assist in improving 3D modeling techniques under complex geological conditions. 展开更多
关键词 3D geological structure model model quality UNCERTAINTY 3D geological modeling
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Construction and Analysis of Three-dimensional Graphic Model of Single-chain Fv Derived from an Anti-human Placental Acidic Isoferritin Monoclonal Antibody by Computer 被引量:3
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作者 周春 沈关心 +4 位作者 朱慧芬 杨静 张悦 冯健南 沈倍奋 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2000年第1期23-25,共3页
Summary: A three-dimensional (3D) graphic model of a single-chain Fv (scFv) which was derived from an anti-human placental acidic isoferritin (PAF) monoclonal antibody (MAb) was construct- ed by a homologous protein... Summary: A three-dimensional (3D) graphic model of a single-chain Fv (scFv) which was derived from an anti-human placental acidic isoferritin (PAF) monoclonal antibody (MAb) was construct- ed by a homologous protein-predicting computer algorithm on Silicon graphic computer station. The structure, surface static electricity and hydrophobicity of scFv were investigated. Computer graphic modelling indicated that all regions of scFv including the linker, variable regions of the heavy (VH) and light (VL) chains were suitable. The VH region and the VL region were involved in composing the 'hydrophobic pocket'. The linker was drifted away VH and VL regions. The complementarity determining regions (CDRs) of VH and VL regions surrounded the 'hydrophobic pocket'. This study provides a theory basis for improving antibody affinity, investigating antibody structure and analyzing the functions of VH and VL regions in antibody activity. 展开更多
关键词 placental acidic isoferritin single-chain Fv three-dimensional structure com- puter modelling
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Three-Dimensional Water-Quality Simulation for River Based on VOF Method 被引量:1
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作者 Ao Xuefei Wang Xiaoling +2 位作者 Song Mingrui Deng Shaohui Li Songmin 《Transactions of Tianjin University》 EI CAS 2016年第5期426-433,共8页
In the present study, considering the transport and transformation processes of variables, a threedimensional water quality model for the river system was established, which coupled the volume of fluid(VOF) method wit... In the present study, considering the transport and transformation processes of variables, a threedimensional water quality model for the river system was established, which coupled the volume of fluid(VOF) method with the k-ε turbulence mathematical model. Then, the water hydrodynamic characteristics and transport processes for BOD_5, NH_(3^-)N and TP were analyzed. The results showed that the water surface of convex bank was a little lower than that of concave bank due to the centrifugal force near the bend, and most concentrations were inferior to the type Ⅴ standard indexes of surface water environmental quality. The model validation indicated that the errors between the simulated and monitored values were comparatively small, satisfying the application demands and providing scientific basis and decision support for the restoration and protection of water quality. 展开更多
关键词 three-dimensional WATER quality model volume of FLUID method k-ε turbulence mathematical model RIVER WATER quality computational FLUID dynamics
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Quality Management Model for Phase I Clinical Drug Trials:A Structural Equation Model 被引量:1
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作者 Yang ZHAO Qiu-xia YANG +1 位作者 Dan WANG Xin-ping ZHANG 《Current Medical Science》 SCIE CAS 2020年第3期586-593,共8页
This study aimed to construct a quality management model for phase I clinical drug trials.A cross-sectional survey was conducted and data were collected from 604 respondents at 69 institutions in China engaged in phas... This study aimed to construct a quality management model for phase I clinical drug trials.A cross-sectional survey was conducted and data were collected from 604 respondents at 69 institutions in China engaged in phase I clinical drug trials.Exploratory and confirmatory factor analyses were used to develop the survey tool.Structural equation modeling was used to construct a quality management model for phase I clinical drug trials.The results showed that the final survey tool had good reliability and validity(Cronbach’sα=0.938,root mean square error of approximation=0.074,comparative fit index=0.962,and Tucker—Lewis index=0.955).The model included five dimensions:government regulation,industry management,medical institution management,research team management,and contract research organization(CRO)management.In total,22 measurement items were obtained.The structural equation model indicated government regulation,industry management,medical institution management,and CRO management significantly affected the quality of phase I clinical drug trials(β=0.195,β=0.331,β=0.279,andβ=−0.267,respectively;P<0.05).Research team management had no effect on the quality of trials(β=0.041,P=0.610).In conclusion,the model is valuable for identifying factors influencing phase I clinical drug trials and guiding quality management practices. 展开更多
关键词 phase I clinical drug trials quality MANAGEMENT influence factor structural equation model
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Application of Structural Equation Modeling to Evaluate Service Quality of Sportswear Retailing 被引量:1
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作者 李敏 顾彤宇 +1 位作者 杨以雄 洪涛敏 《Journal of Donghua University(English Edition)》 EI CAS 2008年第1期6-10,共5页
Structural Equation Modeling (SEM) used widely in sociology, economics and psychology is adopted. Based on data obtained from marketing research, and using statistical analysis software SPSSll. 0 and LISRELS. 7, The... Structural Equation Modeling (SEM) used widely in sociology, economics and psychology is adopted. Based on data obtained from marketing research, and using statistical analysis software SPSSll. 0 and LISRELS. 7, Theory of Five Dimensions of service quality is proved to be suitable in sportswear retailing in China. It analyzes the relationship among five dimensions and puts them in order of importance as to service quality in sportswear retailing. Advices are given for sportswear retail companies to improve their .Service quality and enhance customer loyalty. 展开更多
关键词 service quality Theory of Five Dimensions SPORTSWEAR structural Equation modeling (SEM)
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Three-dimensional coupled-mode model and characteristics of low-frequency sound propagation in ocean waveguide with seamount topography
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作者 Ya-Xiao Mo Chao-Jin Zhang +1 位作者 Li-Cheng Lu Sheng-Ming Guo 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第8期453-462,共10页
Large-scale topography, such as a seamount, substantially impacts low-frequency sound propagation in an ocean waveguide, limiting the application of low-frequency acoustic detecting techniques. A three-dimensional(3D)... Large-scale topography, such as a seamount, substantially impacts low-frequency sound propagation in an ocean waveguide, limiting the application of low-frequency acoustic detecting techniques. A three-dimensional(3D) coupledmode model is developed to calculate the acoustic field in an ocean waveguide with seamount topography and analyze the3D effect. In this model, a correction is introduced in the bottom boundary, theoretically making the acoustic field satisfy the energy conservation. Furthermore, a large azimuth angle calculation range is obtained by using the operator theory and higher-order Pade approximation. Additionally, the model has advantages related to the coupling mode and parabolic equation theory. The couplings corresponding to the effects of range-dependent environment are fully considered, and the numerical implementation is kept feasible. After verifying the accuracy and reliability of the model, low-frequency sound propagation characteristics in the seamount environment are analyzed. The results indicate lateral variability in bathymetry can lead to out-of-plane effects such as the horizontal refraction phenomenon, while the coupling effect tends to restore the abnormal sound field and produces acoustic field diffraction behind the seamount. This model effectively considers the effects of the horizontal refraction and coupling, which are proportional to the scale of the seamount. 展开更多
关键词 coupled-mode model three-dimensional sound propagation seamount topography horizontal interference structure
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On the Fabrication of Structural Model of Quality System of Urbanization in China
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作者 Benzheng Xie Dehong Liu 《Chinese Business Review》 2004年第11期38-42,共5页
This paper classifies the factors related with the quality system of the urbanization into three dimensions as quality planning, quality realization and quality improvement according to the relationship of their mutua... This paper classifies the factors related with the quality system of the urbanization into three dimensions as quality planning, quality realization and quality improvement according to the relationship of their mutual actions. Then it fabricates a three-dimension space structural model. In order to achieve sustainable improvement on urbanization quality improvement, this paper puts forward the measures of controlling the operation of the quality system of urbanization to make it run effectively and smoothly. 展开更多
关键词 URBANIZATION quality system structural model
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Application of Structural Equation Model to Evaluate the Perception of Service Quality of Medical Staffs of infectious Disease Department in Chinese Hospitals
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作者 Min Li Ren-tian Cai Cheng-yu Huang 《国际感染病学(电子版)》 CAS 2014年第4期179-186,共8页
Objective To enhance the quality of medical service for Chinese patients through research of service quality from Chinese medical personnel. Methods Serv Qual scale was used for infection medical staffs randomly by sa... Objective To enhance the quality of medical service for Chinese patients through research of service quality from Chinese medical personnel. Methods Serv Qual scale was used for infection medical staffs randomly by sampling questionnaire in Beijing, Shanghai, Chengdu, Chongqing, Guangzhou and Nanning. The data collected were entered and analyzed using SPSS 20.0. Statistical methods included frequency, factor analysis, reliability analysis, correlation analysis, independent samples t test, one-way analyses of variance, simultaneous regression analysis and structural equation model analysis. Results The Kaiser-Meyer-Olkin value for the factor analysis of the scale was 0.970. The Cronbach's α for the reliability analysis was 0.975. The Pearson correlation coefficients were 0.624-0.874 and statistically significant. Undergraduates felt good, Ph D students felt bad; the doctors felt bad; managers felt good. Standard 5 dimensions of the regression coefficients were positive, including empathy(β = 0.288), reliability(β = 0.241) impacting on perceived service quality mostly. The control ability and stability of the standard error of perceived service quality directly effected value were 0.646 and 0.382, respectively. Conclusions Medical staffs of infectious disease department have poor perception of service quality. Hospitals should improve awareness and of clinicians and deepen the reform of the medical care system. 展开更多
关键词 structural equation models Infectious disease department Perception of service quality
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Mathematical Modeling of the Influence of the Wind Field Structure in the Atmosphere on the Cloud Formation Processes
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作者 Boris A. Ashabokov Lyudmila M. Fedchenko +4 位作者 Alexander V. Shapovalov Khazhbara M. Kalov Ruslan Kh. Kalov Alla A. Tashilova Vitaly A. Shapovalov 《Atmospheric and Climate Sciences》 2018年第1期84-96,共13页
The state of the physics of convective clouds and cloud seeding is discussed briefly. It is noted that at the present time there is a transition from the stage of investigation of “elementary” processes in the cloud... The state of the physics of convective clouds and cloud seeding is discussed briefly. It is noted that at the present time there is a transition from the stage of investigation of “elementary” processes in the clouds to the stage of studying the formation of macro- and microstructural characteristics of clouds as a whole, taking into account their system properties. The main directions of the development of cloud physics at the upcoming stage of its development are discussed. The paper points out that one of these areas is the determination of the structure-forming factors for the clouds and the study of their influence on their formation and evolution. It is noted that one of such factors is the interaction of clouds with their surrounding atmosphere, and the main method of studying its role in the processes of cloud formation is mathematical modeling. A three-dimensional nonstationary model of convective clouds is presented with a detailed account of the processes of thermohydrodynamics and microphysics, which is used for research. The results of modeling the influence of the wind field structure in the atmosphere on the formation and evolution of clouds are presented. It is shown that the dynamic characteristics of the atmosphere have a significant effect on the formation of macro- and microstructural characteristics of convective clouds: the more complex the structure of the wind field in the atmosphere (i.e., the more intense the interaction of the atmosphere and the cloud), the less powerful the clouds are formed. 展开更多
关键词 WIND in the ATMOSPHERE WIND Field structure INTERACTION with CLOUDS Mod-eling System Properties of CLOUDS INTERACTION of CLOUDS with the ATMOSPHERE three-dimensional Cloud model
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Analysis of Quality of Life in Cancer Patients by Structural Equation Model
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作者 Hengqing Tong Shudan Lu +1 位作者 Yang Ye Yichao Pan 《Journal of Cancer Therapy》 2010年第2期71-75,共5页
Many people have been dead of cancer. The life quality of patients with cancer has aroused great concern from the public and specialists. In this paper, an index system of life quality is proposed to evaluate the qual... Many people have been dead of cancer. The life quality of patients with cancer has aroused great concern from the public and specialists. In this paper, an index system of life quality is proposed to evaluate the quality of life, which includes 6 first-level indexes and 34 second-level indexes. Then, a structural equation model (SEM) based on these in-dexes and relationships among them is constructed for the analysis of quality of life in cancer patients. Furthermore, we offer a definite linear algorithm for the calculation of SEM. This method is more objective and scientific compared with traditional methods, such as descriptive analysis, some simple test methods and so on. 展开更多
关键词 quality of Life structural Equation model Unit Vector Constraint Definite Linear Algorithm
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Tekla Structures软件在油气田地面工程加工设计中的应用 被引量:4
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作者 苗升 《石油工程建设》 2015年第2期47-51,共5页
为提高油气田地面工程建设质量和效率,工程详细设计完成后进行加工设计十分必要。文章结合中石化胜利油建工程有限公司在伊朗和加纳的油气田地面工程项目,详细介绍了应用Tekla Structures软件进行钢结构加工设计的优越性和具体做法。该... 为提高油气田地面工程建设质量和效率,工程详细设计完成后进行加工设计十分必要。文章结合中石化胜利油建工程有限公司在伊朗和加纳的油气田地面工程项目,详细介绍了应用Tekla Structures软件进行钢结构加工设计的优越性和具体做法。该软件能快捷、准确地创建结构3D模型,且自动生成所需的图纸和各种精确报表,便于发现加工设计中的问题从而进一步优化设计,对节约工程成本和缩短工期具有重要意义。 展开更多
关键词 质量和效率 Tekla structures软件 3D建模 钢结构 油气田地面工程 模块化施工
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A model of quality control based on recycling economy and sustainable manufacture 被引量:1
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作者 Chert Xiangyu Liang Gongqian Ma Shining 《Ecological Economy》 2006年第1期16-24,共9页
People currentiy pay attention to a hotspot problem that how industrial production is evaluated and controlled based on sustainable development theory. Quality is one of the important indexes. Two mainstream theories ... People currentiy pay attention to a hotspot problem that how industrial production is evaluated and controlled based on sustainable development theory. Quality is one of the important indexes. Two mainstream theories guide us to realize the industrial sustainable development: mainly the circular economy and sustainable manufacturing are introduced. The basic characteristics of the sustainable manufacturing are introduced, and that quality management is important contents of sustainable development is indicated. Based on circular economy and sustainable manufacture theories, the drawbacks in the existing quality management models are analyzed. The requests that satisfy the big system "environment- society - economy" are summarized to build up a model. A Chinese traditional cultural principle is applied and the relevant contents are sublimated as the platform to set up the model. The new quality management concept models are put forward "T- D- R" three-dimensional structures and "ecological quality loop" model, from which the new quality concepts are formed The paper elaborates the contents and the process of setting up the models. The big quality problems of the system can be handled by the new quality concept and model that are validated in practice. 展开更多
关键词 Sustainable development: quality management Big system three-dimensional structures model
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Analysis and Forecast of China’s Grain Supply and Demand Quality Grade Structural Balance
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作者 Bingjun Li Weiming Yang Mengfei Wu 《American Journal of Plant Sciences》 2018年第8期1747-1758,共12页
Based on the analysis of China’s grain production and demand quality grade, this paper uses the non-equidistance GM (1,1) model and the inference algorithm to predict the structural balance of the supply and demand g... Based on the analysis of China’s grain production and demand quality grade, this paper uses the non-equidistance GM (1,1) model and the inference algorithm to predict the structural balance of the supply and demand grades of China’s four major grain crops. The results show that the supply and demand for wheat, corn and rice can maintain a quantitative balance. While, it’s difficult to achieve a quality grade balance in wheat and rice and keep a supply and demand balance in terms of quantity and quality of soybean. Simultaneously, the supply of premium grade corn is greater than the demand. The analysis and prediction results can reflect the existing structural balance matter of grain supply and demand at different quality grades in China, and provide theoretical basis for governments to formulate relevant policies. 展开更多
关键词 quality GRADE Supply-Demand structure Non-Equidistance GM (1 1) model
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Evaluation and Driving Force Analysis of Cultivated Land Quality in Black Soil Region of Northeast China 被引量:1
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作者 WANG Mingchang LIU Xingnan +4 位作者 LIU Ziwei WANG Fengyan LI Xiaoyan HOU Guanglei ZHAO Shijun 《Chinese Geographical Science》 SCIE CSCD 2023年第4期601-615,共15页
Cultivated land is an important natural resource to ensure food,ecological and economic security.The cultivated land quality evaluation(CQE)is greatly significant for protecting and managing cultivated land.In this st... Cultivated land is an important natural resource to ensure food,ecological and economic security.The cultivated land quality evaluation(CQE)is greatly significant for protecting and managing cultivated land.In this study,320 counties in the black soil region of Northeast China(BSRNC)represent the research units used to construct the CQE system measuring the soil properties(SP),cultivated land productivity(CLP),ecological environment(EE)and social economy(SE).The total of 19 factors were selected to calculate the integrated fertility index(IFI)and divided into grades.Simultaneously,we used the coupling coordination degree model to comprehensively analyze the spatial pattern of the cultivated land quality(CLQ)in the BSRNC,and use the structural equation model(SEM)to analyze the driving mechanism.The results show the following:1)The CLQ of 262 counties in the BSRNC is in a state of coupling and coordination,and the coupling and coordination degree presents a spatial distribution pattern of‘high in the southwest and northeast,low in the northwest and southeast’.The coordinated development degree of 271 counties is between 0.4 and 0.6,which is in a transitional state between coordination and disorder.2)The CLQ in the BSRNC is generally good,with an average grade of 3.High-quality cultivated land accounts for 58.45%of all counties,middle-and upper-quality cultivated land accounts for 27.05%,and poor-quality cultivated land accounts for 14.49%.3)The SEM analysis shows that the SP,CLP,EE,and SE all influence the CLQ.Among them,the SP has the largest driving force on the CLQ,while the SE has the smallest driving force on it.The results confirm that the main factors affecting the evaluation results are crop productivity level,normalized difference vegetation index,ratio vegetation index,difference vegetation index,and organic carbon content.When implementing protection measures in counties with a low CLQ,considering a balanced coordination of multiple systems and reasonably controlling the quality degradation are important.This study provides the current situation and driving factors of the CLQ in the BSRNC and will play an important role in black soil governance and utilization. 展开更多
关键词 cultivated land quality evaluation(CQE) black soil region of Northeast China(BSRNC) coupling coordination degree model structural equation model(SEM) driving forces
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Quality Management Model Embodying Circular Economy and Sustainable Manufacture - Quality Concept Models Based on a Chinese Traditional Cultural Principle
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作者 CHEN Xiang-yu LIANG Gong-qian MA Shi-ning 《Journal of Donghua University(English Edition)》 EI CAS 2005年第5期16-21,共6页
Based on circular economy and sustainable manufacture theories, the drawbacks in the existing quality management models are analyzed. The requests that satisfy the big system 'environment-society-economy' are ... Based on circular economy and sustainable manufacture theories, the drawbacks in the existing quality management models are analyzed. The requests that satisfy the big system 'environment-society-economy' are summarized to build up a model. A Chinese traditional cultural principle is applied and the relevant contents are sublimated as the platform to set up the model. The new quality management concept models are put forward: 'T-D-R' three dimension structures and 'ecological quality loop' model, from which the new quality concepts are formed. The paper elaborates the contents and the process of setting up the models. The big system quality problems can be handled by the new quality concept and model that are validated in practice. 展开更多
关键词 sustainable development quality management big system three dimension structures model
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