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采用流管元测量冰期流量及流速分布的方法 被引量:1
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作者 潘佳佳 郭新蕾 +3 位作者 王涛 付辉 李甲振 郭永鑫 《水利学报》 EI CSCD 北大核心 2020年第12期1536-1543,共8页
北方河流冰期测流需要在冰盖上沿断面打孔,再测量各孔垂线流速分布,最后通过流速积分得到冰盖下的总流量。这种传统的冰期测流是一项耗时耗力且高风险的工作,限制了冰期流量流速资料的采集。本文基于流管元法和爱因斯坦的断面分区方法,... 北方河流冰期测流需要在冰盖上沿断面打孔,再测量各孔垂线流速分布,最后通过流速积分得到冰盖下的总流量。这种传统的冰期测流是一项耗时耗力且高风险的工作,限制了冰期流量流速资料的采集。本文基于流管元法和爱因斯坦的断面分区方法,提出一种基于理论公式的冰期测流方法。该方法被用于实验条件下复式断面的流速分布和黄河不同断面的流量计算。结果显示新方法获得的断面流量、单宽流量分布和水深平均的流速分布与实验值和现场观测值符合良好。基于流管元的冰期测流方法能广泛用于明流、部分冰封和完全冰封河道断面的流量及流速分布测量,能有效减少冰期测流工作量、提高测量效率,进而减少测量人员安全风险,可在水文观测中推广应用。 展开更多
关键词 流管元 部分冰盖 断面速分布 北方河
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Multicenter Clinical Randomized Controlled Trial and Network Pharmacology Analysis of Zhenzhu Qingyuan Granules for the Treatment of Gastroesophageal Reflux Disease
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作者 Mengge Li Zhibo Dang +7 位作者 Peiguo Qian Zhenhuan Yang Lei Luo Bo Li Xingzhou Xia Yingjie Ma Zhongqin Dang Yuliang Wang 《Chinese Medicine and Natural Products》 CAS 2024年第3期106-116,共11页
Objective To evaluate the clinical efficacy and safety of Zhenzhu Qingyuan Granules through a clinical randomized controlled trial and to analyze the potential action targets and pathways of this formula using network... Objective To evaluate the clinical efficacy and safety of Zhenzhu Qingyuan Granules through a clinical randomized controlled trial and to analyze the potential action targets and pathways of this formula using network pharmacology.Methods Patients with gastroesophageal reflux disease(GERD)of liver–stomach stagnant heat pattern who met the inclusion and exclusion criteria were randomly divided into the control group and the observation group.The control group received oral rabeprazole,whereas the observation group were given Zhenzhu Qingyuan Granules in addition to the rabeprazole.The treatment duration was 8 weeks.Clinical efficacy was observed in both groups after 8 weeks.Network pharmacology was used to analyze the action targets of ZhenzhuQingyuanGranules and the genes related to GERD,and core targets were inferred.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were conducted to explore the potential mechanisms of this formula.Results The clinical research results showed that the total effective rate in the treatment group was 92.68%,compared with 70.00%in the control group,with a statistically significant difference(p<0.05).After treatment,both Chinese medicine syndrome score and endoscopic score improved in both groups compared with before treatment(p<0.05),and the treatment group showed greater improvement than the control group(p<0.05).Network pharmacology identified effective components of Zhenzhu Qingyuan Granules for treating GERD,including quercetin,luteolin,andβ-sitosterol,with potential action targets such as tumor protein 53(TP53),protein kinase B(AKT1),and tumor necrosis factor.Conclusion Zhenzhu Qingyuan Granules can significantly improve clinical symptoms in patients with GERD of liver–stomach stagnated heat pattern,enhance clinical efficacy,and have high safety.This formula may exert therapeutic effects through multiple targets and pathways. 展开更多
关键词 gastroesophageal reflux disease Zhenzhu Qingyuan Granules liver–stomach stagnated heat syndrome randomized controlled trial network pharmacology
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Wavefield simulation in porous media saturated with two immiscible fluids 被引量:2
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作者 田迎春 马坚伟 杨慧珠 《Applied Geophysics》 SCIE CSCD 2010年第1期57-65,99,100,共11页
Wavefields in porous media saturated by two immiscible fluids are simulated in this paper.Based on the sealed system theory,the medium model considers both the relative motion between the fluids and the solid skeleton... Wavefields in porous media saturated by two immiscible fluids are simulated in this paper.Based on the sealed system theory,the medium model considers both the relative motion between the fluids and the solid skeleton and the relaxation mechanisms of porosity and saturation(capillary pressure).So it accurately simulates the numerical attenuation property of the wavefields and is much closer to actual earth media in exploration than the equivalent liquid model and the unsaturated porous medium model on the basis of open system theory.The velocity and attenuation for different wave modes in this medium have been discussed in previous literature but studies of the complete wave-field have not been reported.In our work,wave equations with the relaxation mechanisms of capillary pressure and the porosity are derived.Furthermore,the wavefield and its characteristics are studied using the numerical finite element method.The results show that the slow P3-wave in the non-wetting phase can be observed clearly in the seismic band.The relaxation of capillary pressure and the porosity greatly affect the displacement of the non-wetting phase.More specifically,the displacement decreases with increasing relaxation coefficient. 展开更多
关键词 porous medium immiscible fluids capillary pressure finite element method wavefield simulation
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Research on workflow meta model supporting activity based costing
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作者 周晓俊 曹建 《Journal of Southeast University(English Edition)》 EI CAS 2003年第4期324-330,共7页
Activity based costing (ABC) is a method which can solve many limitations of the traditional cost systems in manufacturing management. In this paper, we investigate how to integrate ABC with workflow technology, and ... Activity based costing (ABC) is a method which can solve many limitations of the traditional cost systems in manufacturing management. In this paper, we investigate how to integrate ABC with workflow technology, and build a workflow meta model supporting ABC. Firstly, the concept and concept model of activity based costing (ABC) are introduced. Next, the meta model of P -PROCE (Process, Product, Resource, Organization, and Cost & Evaluation) is presented. Then the cost meta model is defined by adding ABC to P -PROCE model. Object constraint language (OCL) is used to express meta model and constraints. Finally, we show an enterprise modeling and simulation tool based on the workflow meta model. We can systematically construct an enterprise model and easily and efficiently conduct simulation. Moreover it enables us to analyze and evaluate business processes and its costs. 展开更多
关键词 activity based costing WORKFLOW meta model object constraint language enterprise model
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The Finite Element Analysis for Parallel-wire Capacitance Probe in Small Diameter Two-phase Flow Pipe 被引量:1
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作者 翟路生 金宁德 +1 位作者 高忠科 黄旭 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第7期813-819,共7页
This paper presents a novel capacitance probe, i.e., paraUel-wire capacitance probe (PWCP), for two-phase flow measurement. Using finite element method (FEM), the sensitivity field of the PWCP is investigated and ... This paper presents a novel capacitance probe, i.e., paraUel-wire capacitance probe (PWCP), for two-phase flow measurement. Using finite element method (FEM), the sensitivity field of the PWCP is investigated and the optimum sensor geometry is determiend in term of the characterisitc parameters. Then, the response of PWCP for the oil-water stratified flow is calculated, and it is found the PWCP has better linearity and sensitivity to the variation of water-layer thickness, and is almost independant of the angle between the oil-water interface and the sensor electrode. Finally, the static experiment for oil-water stratified flow is carried out and the calibration method of liquid holdup is presented. 展开更多
关键词 parallel-wire capacitance probe finite element analysis sensitivity field oil-water stratified flow
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Analysis of barrel structure optimization for a mortar
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作者 刘麒峰 赵捍东 解加庆 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第3期258-263,共6页
Considering the maximum elastic limitation of the used material with newly advanced technology,the study focuses on optimization of a mortar barrel structure by thinning the wall to reduce the weight.Firstly,static an... Considering the maximum elastic limitation of the used material with newly advanced technology,the study focuses on optimization of a mortar barrel structure by thinning the wall to reduce the weight.Firstly,static analysis of barrel structure parameters is done based on finite element analysis(FEA)method and 3Dsolid model of the barrel is established based on Unigraphics NX(UG).Secondly,the 3Dsolid model is simplified and transplanted to ANSYS for barrel wall pressure calculation.Thus,the change curves of the stress exerted on the barrel wall at different locations perpendicular to the axial direction with wall thinning are drawn.By analyzing all possible optimization schemes,the optimal design that enables the barrel to have higher bearing capacity is got.The optimized barrel structure is verified by means of fluid-solid coupling dynamic response analysis.The results show that the static analysis results are closer to real stress conditions than dynamic analysis results.Finally,the barrel weight is reduced by 13%after simulation optimization and the light weight design of the barrel is effective and reliable. 展开更多
关键词 BARREL finite element analysis(FEA) Unigraphics NX(UG) fluid-solid coupling
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Liquid holdup measurement with double helix capacitance sensor in horizontal oil-water two-phase flow pipes 被引量:5
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作者 翟路生 金宁德 +1 位作者 高忠科 王振亚 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期268-275,共8页
This paper presents the characteristics of a double helix capacitance sensor for measurement of the liquid holdup in horizontal oil–water two-phase flow. The finite element method is used to calculate the sensitivity... This paper presents the characteristics of a double helix capacitance sensor for measurement of the liquid holdup in horizontal oil–water two-phase flow. The finite element method is used to calculate the sensitivity field of the sensor in a pipe with 20 mm inner diameter and the effect of sensor geometry on the distribution of sensitivity field is presented. Then, a horizontal oil–water two-phase flow experiment is carried out to measure the response of the double helix capacitance sensor, in which a novel method is proposed to calibrate the liquid holdup based on three pairs of parallel-wire capacitance probes. The performance of the sensor is analyzed in terms of the flow structures detected by mini-conductance array probes. 展开更多
关键词 Horizontal oil–water two-phase flow Liquid holdup measurement Double helix capacitance sensor Flow pattern
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Fluid-solid interaction of resistance loss of flexible hose in deep ocean mining 被引量:3
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作者 王志 饶秋华 刘少军 《Journal of Central South University》 SCIE EI CAS 2012年第11期3188-3193,共6页
The resistance loss of transportation was studied and the influences of buoyancy layout,mineral content and elastic modulus of flexible hose were investigated based on three-dimensional finite element model of fluid-s... The resistance loss of transportation was studied and the influences of buoyancy layout,mineral content and elastic modulus of flexible hose were investigated based on three-dimensional finite element model of fluid-solid interaction by MSC.MARC/MENTAT software.The numerical results show that the resistance losses increase with the increase of mineral content Cv and velocity of internal fluid v and decrease with the increase of elastic modulus E of flexible hose.The buoyancy layout and the velocity of internal fluid have greater impacts on the resistance losses than the elastic modulus of flexible hose.In order to reduce the resistance losses and improve the efficiency of the deep-ocean mining,Cv and v must be restricted in a suitable range (e.g.10%-25% and 2.5-4 m/s).Effective buoyancy layout (such as Scheme C and D) should be adopted and the suitable material of moderate E should be used for the flexible hose in deep-ocean mining. 展开更多
关键词 resistance loss flexible hose fluid-solid interaction deep-ocean mining finite element method
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Study of Models for Heating Power Station Operator Training Systems
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作者 Sholpan Muratkyzy Baimatayeva Yuriy Vladimirovitch Shevyakov 《Journal of Energy and Power Engineering》 2013年第1期162-167,共6页
This paper is devoted to development and study of models for operator training systems of heating power station processes management. It proposed a mathematical model describing the management processes of heating pow... This paper is devoted to development and study of models for operator training systems of heating power station processes management. It proposed a mathematical model describing the management processes of heating power units of the technological complex considering the relationship of technological variables in deviations effective in real time. A software complex is developed for the system of training of operators controlling processes in heating station units. Obtained results may be used in the course of development of computer training systems for operators of heating power stations with cross-linkage. 展开更多
关键词 Training systems of operators steam generator simulation model heating power stations
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Heat Transfer Behavior in a Square Duct with Tandem Wire Coil Element Insert
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作者 Smith Eiamsa-ard Narin Koolnapadol Pongjet Promvonge 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第5期863-869,共7页
Effects of insertion of tandem wire coil elements used as turbulator on heat transfer and turbulent flow friction characteristics in a uniform heat-flux square duct are experimentally investigated in this work. The ex... Effects of insertion of tandem wire coil elements used as turbulator on heat transfer and turbulent flow friction characteristics in a uniform heat-flux square duct are experimentally investigated in this work. The experiment is conducted for turbulent flow with the Reynolds number from 4000 to 25000. The wire coil element is inserted into the duct with a view to generating a swirl flow that assists to wash up the flow trapped in the duct corners and then increase the heat transfer rate of the test duct. Apart from the full-length coil, 1D and 2D length coil elements placed in tandem inside the duct with various free-space lengths are introduced to reduce the friction loss. The results obtained from these wire coil element inserts are also compared with those from the smooth duct. The experimental results reveal that the use of wire coil inserts for the full-length coil, 1D and 2D coil elements with a short free-space length leads to a considerable increase in heat transfer and friction loss over the smooth duct with no insert. The full-length wire coil provides higher heat transfer and friction factor than the tandem wire coil elements under the same operating conditions. Also, performance evaluation criteria to assess the real benefits in using the wire coil insert into the square duct are determined. 展开更多
关键词 heat transfer wire coil insert square duct TURBULATOR
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Experimental Acoustic Determination of the Void Fraction in Two-Phase Flow in Horizontal Pipelines
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作者 Fernando Augusto de Noronha Castro Pinto Thiago de Campos Negrelly Alexandre Silva de Lima 《Journal of Mechanics Engineering and Automation》 2014年第8期625-631,共7页
In multi-phase flows, the phases can flow and arranged in different spatial configurations in the pipe, which called flow patterns. This type of flow is found in the oil, chemical and nuclear industries. For example, ... In multi-phase flows, the phases can flow and arranged in different spatial configurations in the pipe, which called flow patterns. This type of flow is found in the oil, chemical and nuclear industries. For example, in the production and transport of oil and gas, the identification of the flow patterns are essential for answering those questions which are related to the economic return of the field, such as, measuring the volumetric flow, determining the pressure drop along the flow lines, production management and supervision. In offshore production, these factors are very important. This paper presents a new method for measuring the void fraction in horizontal pipelines, taking the air as gas in water-air two-phase flow. Through acoustic analysis of the frequency response of the pipe, the method gets the parameters to changes in runoff regime, in an experimental arrangement constructed on a small scale. The main advantages are the non-intrusive characteristic and easy to implement. The paper is composed of a qualitative experimental evaluation and transducers (microphone) which are used to analyze variations in the response accompanying variations in void and flow pattern changes. Changes are imposed and controlled by a two-phase flow experimental simulation rig, including a measurement cell constituted of an external casing that can isolate the measurement from the environmental background noise fitted with acoustic pressure transducers radially arranged, and the impact of a monitored excitation mechanism. The signals which captured by the microphones are processed and analyzed by checking their frequency contents changes according to the amount of air in the mixture. 展开更多
关键词 Experimental method two-phase flow determination of void fraction horizontal pipelines.
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Information System Functions for SmartGrid Management
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作者 Mila llieva-Obretenova 《Sociology Study》 2016年第2期96-103,共8页
The violently penetration of renewables in power supply network leads to situations, by which the offer exceeds the demand. Therefore, it is necessary to include a system for processes' management. SmartGrid is a pla... The violently penetration of renewables in power supply network leads to situations, by which the offer exceeds the demand. Therefore, it is necessary to include a system for processes' management. SmartGrid is a platform over the power supply network. It is represented with its network and services, which also have to be managed. The paper aims to show the second stage of SmartGrid management modeling. It meets heterogeneous requirements of the actors--subscriber without photovoltaics, subscriber with photovoltaics, service provider, network operator, and network elements operator--to service and network management and is oriented to functional areas, covering the life cycle of power supply service: Design, Planning, Installation, Provision, Configuration, Maintenance, Performance, Accounting, Buying Up, Security and Subscriber Control. Functional models for existing networks--telecommunications--are used and they are adapted to power supply. The results are illustrated with three functional areas for service management: Accounting, Buying Up, and Performance. The synthesis of network management functions and network element management functions are similar. 展开更多
关键词 SmartGrid functional areas service management network management network element management
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