The paper study communication protocol, the structure of the circuit, antenna design of radio frequency identification technology （RFID）, and puts forward a scheme based on IOT application： RFID logistics tracking ...The paper study communication protocol, the structure of the circuit, antenna design of radio frequency identification technology （RFID）, and puts forward a scheme based on IOT application： RFID logistics tracking system. Finally, the paper study the logistics distribution center information management model from three aspects of the system design objectives, system function analysis and system architecture design based on RFID.展开更多
In the new era,college students’interpersonal communication abilities exhibit characteristics such as diversified interpersonal cognition needs,idealized interpersonal emotions,and diversified interpersonal behavior ...In the new era,college students’interpersonal communication abilities exhibit characteristics such as diversified interpersonal cognition needs,idealized interpersonal emotions,and diversified interpersonal behavior patterns.They face issues in coordinating and managing interpersonal relationships with parents,classmates,teachers,and others.Therefore,against the background of party history learning and education,we can deeply explore party history stories and leverage the educational role of the red spirit of party history;continuously strengthen the cultivation of teachers’ethics,hone their abilities in party history learning,and make party history learning a battlefield for harmonious interpersonal relationships among college students;build the“Intelligent Party History”project,innovate party history learning platforms,and let party building lead the development of harmonious interpersonal relationships among college students.展开更多
Thermogravimetric analysis and electrical resistivity were used to determine the hydration process of cement paste with rice husk ash(RHA)(0−15%)and water-cement ratio of 0.4 in this work.X-ray diffraction(XRD)method ...Thermogravimetric analysis and electrical resistivity were used to determine the hydration process of cement paste with rice husk ash(RHA)(0−15%)and water-cement ratio of 0.4 in this work.X-ray diffraction(XRD)method and scanning electron microscopy(SEM)were used to survey crystal composition and microstructures of specimens cured for 3 h,1 d,7 d and 28 d.Finally,electrical parameters(electrical resistance and AC impedance spectroscopy)of steel bars reinforced cement paste were investigated to study the effect of RHA on the corrosion resistance.Results showed that RHA could affect the cement hydration by hydration promotion and pozzolanic effect.The evaluation function for electrical resistivity and curing ages fitted well with linear increasing function.The addition of RHA higher than 5%demonstrated a decreasing role in the electrical resistivity of cement paste at earlier curing ages(3−7 d).Meanwhile,when at later curing ages(7−28 d)the result was the opposite.Moreover,RHA demonstrated positive effects on corrosion resistance of steel bars in cement paste.展开更多
Reference crop evapotranspiration(ET 0) is a key parameter to calculate crop water requirements.In the paper,ET 0 during 1960-2005 was calculated with FAO-56 PM in eastern agricultural areas of Qinghai,China.Then the ...Reference crop evapotranspiration(ET 0) is a key parameter to calculate crop water requirements.In the paper,ET 0 during 1960-2005 was calculated with FAO-56 PM in eastern agricultural areas of Qinghai,China.Then the sensitivity coefficients of ET 0 to meteorological variables were estimated through the nondimensional partial derivative in FAO-56 PM.Results show that the mean annual ET 0 of the whole area is 904 mm,and ET 0 portrays a very significant decrease during the 46 years.In spatial,ET 0 decreases from southeast to northwest,firstly increases then decreases from southwest to northeast.Through sensitivity analysis,in spring the most sensitive variable is relative humidity,while in summer is temperature.The temperature,sunshine duration and wind speed sensitivity coefficients(S(TA),S(n),S(u)) are higher in middle areas as opposed to surrounding areas,while the relative humidity sensitivity coefficient(S(RH)) has an opposite distribution rule.展开更多
An evaluation method for the seismic stability of embankment slope was presented based on catastrophe theory. Seven control factors, including internal frictional angle, cohesion force, slope height, slope angle, surf...An evaluation method for the seismic stability of embankment slope was presented based on catastrophe theory. Seven control factors, including internal frictional angle, cohesion force, slope height, slope angle, surface gradients, peak acceleration, and distance to fault were selected for analysis of multi-level objective decomposition. According to the normalization formula and the fuzzy subject function produced by combination of catastrophe theory and fuzzy math, a recursive calculation was carried out to obtain a catastrophic affiliated functional value, which can be used to evaluate the seismic stability of embankment slope. Fifteen samples were used to verify the effectiveness of this method. The results show that compared with the traditional quantitative method, the catastrophe progression owns higher accuracy and good application potential in predicting the seismic stability of embankment slope.展开更多
Romashkino oil field has large oilfield area, small formation dip, many reservoir layers, wide oil-water transition zone and complicated sedimentary environment. Since development, 3 overall development plannings and ...Romashkino oil field has large oilfield area, small formation dip, many reservoir layers, wide oil-water transition zone and complicated sedimentary environment. Since development, 3 overall development plannings and adjustments of individual block have been established. This achieves a high oil production. However, the recoverable reserves of major oil layer with high production become smaller and smaller and the water cut increases over time, the production ability of oil layer decreases. The development status of oil layer of mining siltstone, oil-water transition zone and oil layer with upswept injected water cannot be changed under present dilute well network condition, because there is no reinforced measurement to water well. This results the low oil production of Romashkino oil field. In order to improve oil production rate and reach the designed oil recovery, Romashkino oil field has been implemented many added cuttings since development. Resent researches about Romashkino oil field show: in later oilfield development stage, sidetrack and lateral drilling horizontal wells technology is very reasonable;formation hydraulic fracturing technology has been widely used in recent years;in tertiary oil recovery, sweep efficiency and flooding efficiency related technologies have been taken. This offers reference and guidance for the effective and reasonable oil field development in later period.展开更多
Influences of different superplasticizers （ STP. KSJSTO and LMS-P） on rheological behavior of low-cement castables and the mechanisms were analyzed. The shear stress and viscosity under different shear rates of matr...Influences of different superplasticizers （ STP. KSJSTO and LMS-P） on rheological behavior of low-cement castables and the mechanisms were analyzed. The shear stress and viscosity under different shear rates of matrix slurry were determined using a NXS-I IA rotary viscometer. Effects of different admixtures on the rheological properties of slurry was analyzed theoretically. Sodium tripolyphosphate and poly＇carboxylate superplasticizers KS-JSTO and LMS-P） can improve the fluidity and initial setting time. With STP. the slurry is plastic flow. With KS-JS70 or LMS-P increasing, the slurrv changes from plastic.flow, pseudoplastic flow to dilatant flow successively. Th, e optimum dosages of STP. KS-JSTO and LMS-P are 0. 15%. 0. 25% and 0. 40%, respectively. KS-JS70 and LMS-P can significantly reduce the slurry viscosity and shear stress to improve the workability of construction. Both shear stress and viscosity shall be taken into account for on-site construction.展开更多
The energy-dispersive spectroscopy （ EDS ） , X-ray diffraction analysis （ XRD ） and differential thermal analysis （DTA） were used to analyze the melting, spreading process, and reaction mechanism of non-corrosiv...The energy-dispersive spectroscopy （ EDS ） , X-ray diffraction analysis （ XRD ） and differential thermal analysis （DTA） were used to analyze the melting, spreading process, and reaction mechanism of non-corrosive flux on the surface of aluminum. The result indicates that the whole process can be divided into three stages. In the first stage, flux is heated from room temperature to its melting point, which is called the endothermic stage, mainly absorbs heat and generates a small amount of liquid flux. When the temperature exceeds the melting point of flux, a large amount of liquid flux is generated and reacts with oxide films on the surface of aluminum. This stage is called the reaction stage. The third stage is a spreading and cleaning process, in which residues and reaction products quickly flow out from the center with liquid flux. The different compositions of flux perform different functions in brazing. K3AlF6 can remove oxide film us a cleaner. Only in liquid or molten state can flux remove oxide film on the substrate.展开更多
In this paper, some concepts and problems in the stress analysis design method are discussed. Based on the introduction of various types of stress characteristics, the differences between stress decomposition and stre...In this paper, some concepts and problems in the stress analysis design method are discussed. Based on the introduction of various types of stress characteristics, the differences between stress decomposition and stress classification are emphasized. We pointed out that the stress decomposition only relates how stress is decomposed into uniform stress, the equivalent stress distribution of linear and nonlinear stress components, how will break out of stress classification, entirely by the stress position and stress the external decision. At the same time, it also gives a valuable perspective on the distribution twe ofoeak stress, the self limitation and the stress decomposition and classification.展开更多
In this paper, we conduct research on the multidimensional constraint stability of bridge structure modeling based on the optimization model. The current internal and the external research results to the truss web str...In this paper, we conduct research on the multidimensional constraint stability of bridge structure modeling based on the optimization model. The current internal and the external research results to the truss web structure, the high internode the aspect ratio and the stiffness of the middle truss brace of the truss web, deffection of composite beams of the impact of stress is a very important problem in the design of the bridge. Structural health monitoring is the use of the field of the non-destructive sensing technology, including the structural response, including structural system characteristics analysis, to achieve the purpose of monitoring structural damage or degradation. Under this basis, this paper proposes the new idea on the modelling and simulates the performance.展开更多
In this paper, we conduct research on the causes and coping strategies of the land subsidence caused by the tunnel construction projects. We analyze the issues from the following of the perspectives. （1） Analysis me...In this paper, we conduct research on the causes and coping strategies of the land subsidence caused by the tunnel construction projects. We analyze the issues from the following of the perspectives. （1） Analysis method. To solve large scale system of the development of computer hardware and the numerical calculation method, we use the basic analysis to deal with it. （2） The empirical of methods. Ground motion is usually leads to the basic development of the inclined tunnel surface vertical displacement, the result of the movement process can turn to a settling tank. （3） Machine learning based approaches. In one of biggest difficulties when using neural network method is to obtain all possible parameters related to ground subsidence, we use the machine learning model to handle the challenge. In the final part, we show prospect for the future research, we will combine more numerical analysis tools to optimize the current methodology.展开更多
The paper introduce the construction method of large segment hosting and its difficulty, and drawing up corresponding liner and stress monitoring plan. The paper gives the calculation method of shear area for such a b...The paper introduce the construction method of large segment hosting and its difficulty, and drawing up corresponding liner and stress monitoring plan. The paper gives the calculation method of shear area for such a big cantilever thin-walled steel box girder section, namely the shear coefficient computation theory of Professor Hu Haichang, and the use of this shear area perfect beam element model, structure model and the experiment prove that the shell model is more consistent, given a certain reference for similar section project.展开更多
Feasibility of oil production predicting results influences the annual planning and long-term field development plan of oil field, so the selection of predicting models plays a core role. In this paper, three differen...Feasibility of oil production predicting results influences the annual planning and long-term field development plan of oil field, so the selection of predicting models plays a core role. In this paper, three different predicting models are introduced, they are neural network model, support vector machine model and GM (1, 1) model. By using these three different models to predict the oil production in XINJIANG oilfield in China, advantages and disadvantages of these models have been discussed. The predicting results show: the fitting accuracy by the neural network model or by the support vector machine model is higher than GM (1, 1) model, the prediction error is smaller than 10%, so neural network model and support vector machine model can be used to short-term forecast of oil production;predicting accuracy by GM (1, 1) model is not good, but the curve trend with GM (1, 1) model is consistent with the downward trend in oil production, so GM (1, 1) predicting model can be used to long-term prediction of oil production.展开更多
The effective implementation of the project management plays a core roll in avoiding bad project use effect and waste of funds, caused by asset management planning and design errors or equipment selection errors;meanw...The effective implementation of the project management plays a core roll in avoiding bad project use effect and waste of funds, caused by asset management planning and design errors or equipment selection errors;meanwhile, it can effectively improve the operational efficiency of enterprise assets, lower operating costs and save resources. In June 1974, A. Gordon published a paper “3L Economics Concept” as the starting point, on the “Building and Quantity Surveying”, which is organized by the Royal Institution of Chartered Surveyors. In this paper, a review of domestic and foreign research, from 1974 to 2015, on the total life cycle management progress will be given, and then a comment on it will be established. After detailed investigation and analysis of related materials, we can draw a conclusion: the study of the oil and gas development project lifecycle management is just beginning now. Hence, building the whole life cycle planning index system in line with the characteristics of oil and gas development project is very necessary.展开更多
In view of the existing situation of gas field development, one kind of method to evaluate the production performance of gas production units (GPUs) was presented in this paper. Among the commonly used indicators of g...In view of the existing situation of gas field development, one kind of method to evaluate the production performance of gas production units (GPUs) was presented in this paper. Among the commonly used indicators of gas field development, we select 11 indicators from the three aspects of production task, gas reservoir management, and production technology. According to the principle of analytic network process (ANP), this paper introduced one kind of new method to get the weights of indicators. By means of the method of TOPSIS, it is easy to obtain the rankings for all the GPUs through calculating the weighted Euclidean distance between each GPU and the positive or negative ideal point. This evaluation method could constantly improve the management level of gas production units and deepen the delicacy management of gas field development.展开更多
Cu/tetrapod-like ZnO whisker （T-ZnOw） compounds were successfully synthesized using N2H4.H2O as a reducing agent by a simple reduction method without any insert gas at room temperature. The crystal phase composition...Cu/tetrapod-like ZnO whisker （T-ZnOw） compounds were successfully synthesized using N2H4.H2O as a reducing agent by a simple reduction method without any insert gas at room temperature. The crystal phase composition and morphology of the as-prepared samples were investigated by XRD, SEM and FESEM tests. The photocatalytic property of the as-prepared samples was detected by the degradation of methyl orange （MO） aqueous solution under UV irradiation. It can be found that Cu nanoparticles （CuNPs） dispersed on the surface of T-ZnOw increased with the increasing of Cu/Zn molar ratios （Cu/Zn MRs）, and an octahedral structure of CuNPs was ob- tained when the sample was prepared with less than and equal to 7.30% Cu/Zn MR, but tended to a spherical or nanorod structure of CuNPs densely arranged on the surface of T-ZnOw, which is prepared by Cu/Zn MRs up to 22.00%. All the compounds exhibited excellent photocatalytic activity in decomposing of MO than T-ZnOw, the photocatalytic property of the samples increased with the increasing of Cu/Zn MRs up to 7.30%, while it decreases when further increasing the Cu/Zn MRs. The Schottky barrier of the Cu/T-ZnOw compound can effectively capture photoinduced electrons from the interface and enhanced the photocatalytic property of T-ZnOw.展开更多
The water flooding characteristic curve method based on the traditional regression equation between the oil and water phase permeability ratio and the water saturation is inappropriate to predict the oil recovery in t...The water flooding characteristic curve method based on the traditional regression equation between the oil and water phase permeability ratio and the water saturation is inappropriate to predict the oil recovery in the high water cut stage. Hence, a new water flooding characteristic curve equation adapted to the high water cut stage is proposed to predict the oil recovery. The water drive phase permeability experiments show that the curve of the oil and water phase permeability ratio vs. the water saturation, in the semi-logarithmic coordinates, has a significantly lower bend after entering the high water cut stage, so the water flooding characteristic curve method based on the traditional regression equation between the oil and water phase permeability ratio and the water saturation is inappropriate to predict the oil recovery in the high water cut stage; therefore, a new water flooding characteristic curve equation based on a better relationship between ln（kro/k,.~） and S~ is urgently desirable to be established to effectively and reliably predict the oil recovery of a water drive reservoir adapted to a high water cut stage. In this paper, by carrying out the water drive phase permeability experiments, a new mathematical model between the oil and water phase permeability ratio and the water saturation is established, with the regression analysis method and an integration of the established model, the water flooding characteristic curve equation adapted to a high water cut stage is obtained. Using the new water flooding characteristic curve to predict the oil recovery of the GD3-block of the SL oilfield and the J09-block of the DG oil field in China, results with high predicted accuracy are obtained.展开更多
Often referred to as the“Third Pole,”China’s Qinghai-Tibetan Plateau developed large amounts of peatland owing to its unique alpine environment.As a renewable resource,peat helps to regulate the climate as well as ...Often referred to as the“Third Pole,”China’s Qinghai-Tibetan Plateau developed large amounts of peatland owing to its unique alpine environment.As a renewable resource,peat helps to regulate the climate as well as performing other important functions.However,in recent years,intensifying climate change and anthropogenic disturbances have resulted in peatland degradation and consequently made sustainable development of peatland more difficult.This review summarizes peatland ecological and economic functions,including carbon sequestration,biodiversity conservation,energy supplies,and ecotourism.It identifies climate change and anthropogenic disturbances as the two key factors attributing to peatland degradation and ecosystem carbon loss.Current problems in environmental degradation and future challenges in peatland management under the effects of global warming are also discussed and highlighted.展开更多
文摘The paper study communication protocol, the structure of the circuit, antenna design of radio frequency identification technology （RFID）, and puts forward a scheme based on IOT application： RFID logistics tracking system. Finally, the paper study the logistics distribution center information management model from three aspects of the system design objectives, system function analysis and system architecture design based on RFID.
文摘In the new era,college students’interpersonal communication abilities exhibit characteristics such as diversified interpersonal cognition needs,idealized interpersonal emotions,and diversified interpersonal behavior patterns.They face issues in coordinating and managing interpersonal relationships with parents,classmates,teachers,and others.Therefore,against the background of party history learning and education,we can deeply explore party history stories and leverage the educational role of the red spirit of party history;continuously strengthen the cultivation of teachers’ethics,hone their abilities in party history learning,and make party history learning a battlefield for harmonious interpersonal relationships among college students;build the“Intelligent Party History”project,innovate party history learning platforms,and let party building lead the development of harmonious interpersonal relationships among college students.
基金Projects(51808300,51778302)supported by the National Natural Science Foundation of ChinaProject supported by the K.C.Wong Magna Fund in Ningbo University,China。
文摘Thermogravimetric analysis and electrical resistivity were used to determine the hydration process of cement paste with rice husk ash(RHA)(0−15%)and water-cement ratio of 0.4 in this work.X-ray diffraction(XRD)method and scanning electron microscopy(SEM)were used to survey crystal composition and microstructures of specimens cured for 3 h,1 d,7 d and 28 d.Finally,electrical parameters(electrical resistance and AC impedance spectroscopy)of steel bars reinforced cement paste were investigated to study the effect of RHA on the corrosion resistance.Results showed that RHA could affect the cement hydration by hydration promotion and pozzolanic effect.The evaluation function for electrical resistivity and curing ages fitted well with linear increasing function.The addition of RHA higher than 5%demonstrated a decreasing role in the electrical resistivity of cement paste at earlier curing ages(3−7 d).Meanwhile,when at later curing ages(7−28 d)the result was the opposite.Moreover,RHA demonstrated positive effects on corrosion resistance of steel bars in cement paste.
基金supported by the Chinese National Natural Science Foundation (51009101)Public Welfare Projects of Ministry of Water Resources in China (201101038)Key Laboratories Open Fund in Sichuan Province-Water-saving Agricultural Research in Southern Hillside Region of China (CJS201201)
文摘Reference crop evapotranspiration(ET 0) is a key parameter to calculate crop water requirements.In the paper,ET 0 during 1960-2005 was calculated with FAO-56 PM in eastern agricultural areas of Qinghai,China.Then the sensitivity coefficients of ET 0 to meteorological variables were estimated through the nondimensional partial derivative in FAO-56 PM.Results show that the mean annual ET 0 of the whole area is 904 mm,and ET 0 portrays a very significant decrease during the 46 years.In spatial,ET 0 decreases from southeast to northwest,firstly increases then decreases from southwest to northeast.Through sensitivity analysis,in spring the most sensitive variable is relative humidity,while in summer is temperature.The temperature,sunshine duration and wind speed sensitivity coefficients(S(TA),S(n),S(u)) are higher in middle areas as opposed to surrounding areas,while the relative humidity sensitivity coefficient(S(RH)) has an opposite distribution rule.
基金financially supported by the open research fund of Key Laboratory of Highway Engineering of Sichuan Province, Southwest Jiaotong University (No. LHTE009201109)
文摘An evaluation method for the seismic stability of embankment slope was presented based on catastrophe theory. Seven control factors, including internal frictional angle, cohesion force, slope height, slope angle, surface gradients, peak acceleration, and distance to fault were selected for analysis of multi-level objective decomposition. According to the normalization formula and the fuzzy subject function produced by combination of catastrophe theory and fuzzy math, a recursive calculation was carried out to obtain a catastrophic affiliated functional value, which can be used to evaluate the seismic stability of embankment slope. Fifteen samples were used to verify the effectiveness of this method. The results show that compared with the traditional quantitative method, the catastrophe progression owns higher accuracy and good application potential in predicting the seismic stability of embankment slope.
文摘Romashkino oil field has large oilfield area, small formation dip, many reservoir layers, wide oil-water transition zone and complicated sedimentary environment. Since development, 3 overall development plannings and adjustments of individual block have been established. This achieves a high oil production. However, the recoverable reserves of major oil layer with high production become smaller and smaller and the water cut increases over time, the production ability of oil layer decreases. The development status of oil layer of mining siltstone, oil-water transition zone and oil layer with upswept injected water cannot be changed under present dilute well network condition, because there is no reinforced measurement to water well. This results the low oil production of Romashkino oil field. In order to improve oil production rate and reach the designed oil recovery, Romashkino oil field has been implemented many added cuttings since development. Resent researches about Romashkino oil field show: in later oilfield development stage, sidetrack and lateral drilling horizontal wells technology is very reasonable;formation hydraulic fracturing technology has been widely used in recent years;in tertiary oil recovery, sweep efficiency and flooding efficiency related technologies have been taken. This offers reference and guidance for the effective and reasonable oil field development in later period.
文摘Influences of different superplasticizers （ STP. KSJSTO and LMS-P） on rheological behavior of low-cement castables and the mechanisms were analyzed. The shear stress and viscosity under different shear rates of matrix slurry were determined using a NXS-I IA rotary viscometer. Effects of different admixtures on the rheological properties of slurry was analyzed theoretically. Sodium tripolyphosphate and poly＇carboxylate superplasticizers KS-JSTO and LMS-P） can improve the fluidity and initial setting time. With STP. the slurry is plastic flow. With KS-JS70 or LMS-P increasing, the slurrv changes from plastic.flow, pseudoplastic flow to dilatant flow successively. Th, e optimum dosages of STP. KS-JSTO and LMS-P are 0. 15%. 0. 25% and 0. 40%, respectively. KS-JS70 and LMS-P can significantly reduce the slurry viscosity and shear stress to improve the workability of construction. Both shear stress and viscosity shall be taken into account for on-site construction.
基金Acknowledgements The authors are grateful to the National Natural Science Foundation of China （ No. 51465032） for financial support.
文摘The energy-dispersive spectroscopy （ EDS ） , X-ray diffraction analysis （ XRD ） and differential thermal analysis （DTA） were used to analyze the melting, spreading process, and reaction mechanism of non-corrosive flux on the surface of aluminum. The result indicates that the whole process can be divided into three stages. In the first stage, flux is heated from room temperature to its melting point, which is called the endothermic stage, mainly absorbs heat and generates a small amount of liquid flux. When the temperature exceeds the melting point of flux, a large amount of liquid flux is generated and reacts with oxide films on the surface of aluminum. This stage is called the reaction stage. The third stage is a spreading and cleaning process, in which residues and reaction products quickly flow out from the center with liquid flux. The different compositions of flux perform different functions in brazing. K3AlF6 can remove oxide film us a cleaner. Only in liquid or molten state can flux remove oxide film on the substrate.
文摘In this paper, some concepts and problems in the stress analysis design method are discussed. Based on the introduction of various types of stress characteristics, the differences between stress decomposition and stress classification are emphasized. We pointed out that the stress decomposition only relates how stress is decomposed into uniform stress, the equivalent stress distribution of linear and nonlinear stress components, how will break out of stress classification, entirely by the stress position and stress the external decision. At the same time, it also gives a valuable perspective on the distribution twe ofoeak stress, the self limitation and the stress decomposition and classification.
文摘In this paper, we conduct research on the multidimensional constraint stability of bridge structure modeling based on the optimization model. The current internal and the external research results to the truss web structure, the high internode the aspect ratio and the stiffness of the middle truss brace of the truss web, deffection of composite beams of the impact of stress is a very important problem in the design of the bridge. Structural health monitoring is the use of the field of the non-destructive sensing technology, including the structural response, including structural system characteristics analysis, to achieve the purpose of monitoring structural damage or degradation. Under this basis, this paper proposes the new idea on the modelling and simulates the performance.
文摘In this paper, we conduct research on the causes and coping strategies of the land subsidence caused by the tunnel construction projects. We analyze the issues from the following of the perspectives. （1） Analysis method. To solve large scale system of the development of computer hardware and the numerical calculation method, we use the basic analysis to deal with it. （2） The empirical of methods. Ground motion is usually leads to the basic development of the inclined tunnel surface vertical displacement, the result of the movement process can turn to a settling tank. （3） Machine learning based approaches. In one of biggest difficulties when using neural network method is to obtain all possible parameters related to ground subsidence, we use the machine learning model to handle the challenge. In the final part, we show prospect for the future research, we will combine more numerical analysis tools to optimize the current methodology.
文摘The paper introduce the construction method of large segment hosting and its difficulty, and drawing up corresponding liner and stress monitoring plan. The paper gives the calculation method of shear area for such a big cantilever thin-walled steel box girder section, namely the shear coefficient computation theory of Professor Hu Haichang, and the use of this shear area perfect beam element model, structure model and the experiment prove that the shell model is more consistent, given a certain reference for similar section project.
文摘Feasibility of oil production predicting results influences the annual planning and long-term field development plan of oil field, so the selection of predicting models plays a core role. In this paper, three different predicting models are introduced, they are neural network model, support vector machine model and GM (1, 1) model. By using these three different models to predict the oil production in XINJIANG oilfield in China, advantages and disadvantages of these models have been discussed. The predicting results show: the fitting accuracy by the neural network model or by the support vector machine model is higher than GM (1, 1) model, the prediction error is smaller than 10%, so neural network model and support vector machine model can be used to short-term forecast of oil production;predicting accuracy by GM (1, 1) model is not good, but the curve trend with GM (1, 1) model is consistent with the downward trend in oil production, so GM (1, 1) predicting model can be used to long-term prediction of oil production.
文摘The effective implementation of the project management plays a core roll in avoiding bad project use effect and waste of funds, caused by asset management planning and design errors or equipment selection errors;meanwhile, it can effectively improve the operational efficiency of enterprise assets, lower operating costs and save resources. In June 1974, A. Gordon published a paper “3L Economics Concept” as the starting point, on the “Building and Quantity Surveying”, which is organized by the Royal Institution of Chartered Surveyors. In this paper, a review of domestic and foreign research, from 1974 to 2015, on the total life cycle management progress will be given, and then a comment on it will be established. After detailed investigation and analysis of related materials, we can draw a conclusion: the study of the oil and gas development project lifecycle management is just beginning now. Hence, building the whole life cycle planning index system in line with the characteristics of oil and gas development project is very necessary.
文摘In view of the existing situation of gas field development, one kind of method to evaluate the production performance of gas production units (GPUs) was presented in this paper. Among the commonly used indicators of gas field development, we select 11 indicators from the three aspects of production task, gas reservoir management, and production technology. According to the principle of analytic network process (ANP), this paper introduced one kind of new method to get the weights of indicators. By means of the method of TOPSIS, it is easy to obtain the rankings for all the GPUs through calculating the weighted Euclidean distance between each GPU and the positive or negative ideal point. This evaluation method could constantly improve the management level of gas production units and deepen the delicacy management of gas field development.
文摘Cu/tetrapod-like ZnO whisker （T-ZnOw） compounds were successfully synthesized using N2H4.H2O as a reducing agent by a simple reduction method without any insert gas at room temperature. The crystal phase composition and morphology of the as-prepared samples were investigated by XRD, SEM and FESEM tests. The photocatalytic property of the as-prepared samples was detected by the degradation of methyl orange （MO） aqueous solution under UV irradiation. It can be found that Cu nanoparticles （CuNPs） dispersed on the surface of T-ZnOw increased with the increasing of Cu/Zn molar ratios （Cu/Zn MRs）, and an octahedral structure of CuNPs was ob- tained when the sample was prepared with less than and equal to 7.30% Cu/Zn MR, but tended to a spherical or nanorod structure of CuNPs densely arranged on the surface of T-ZnOw, which is prepared by Cu/Zn MRs up to 22.00%. All the compounds exhibited excellent photocatalytic activity in decomposing of MO than T-ZnOw, the photocatalytic property of the samples increased with the increasing of Cu/Zn MRs up to 7.30%, while it decreases when further increasing the Cu/Zn MRs. The Schottky barrier of the Cu/T-ZnOw compound can effectively capture photoinduced electrons from the interface and enhanced the photocatalytic property of T-ZnOw.
基金Project supported by the China Postdoctoral Science Foundation(Grant No,2014M562509XB)the Scientific Project of Sichuan Provincial Education Department(Grant No.15ZB0447)
文摘The water flooding characteristic curve method based on the traditional regression equation between the oil and water phase permeability ratio and the water saturation is inappropriate to predict the oil recovery in the high water cut stage. Hence, a new water flooding characteristic curve equation adapted to the high water cut stage is proposed to predict the oil recovery. The water drive phase permeability experiments show that the curve of the oil and water phase permeability ratio vs. the water saturation, in the semi-logarithmic coordinates, has a significantly lower bend after entering the high water cut stage, so the water flooding characteristic curve method based on the traditional regression equation between the oil and water phase permeability ratio and the water saturation is inappropriate to predict the oil recovery in the high water cut stage; therefore, a new water flooding characteristic curve equation based on a better relationship between ln（kro/k,.~） and S~ is urgently desirable to be established to effectively and reliably predict the oil recovery of a water drive reservoir adapted to a high water cut stage. In this paper, by carrying out the water drive phase permeability experiments, a new mathematical model between the oil and water phase permeability ratio and the water saturation is established, with the regression analysis method and an integration of the established model, the water flooding characteristic curve equation adapted to a high water cut stage is obtained. Using the new water flooding characteristic curve to predict the oil recovery of the GD3-block of the SL oilfield and the J09-block of the DG oil field in China, results with high predicted accuracy are obtained.
基金This study was financially supported by the National Natural Science Foundation of China(41671244)China Postdoctoral Science Foundation Grant(2016M600751)+2 种基金a fund from Chengdu Institute of Biology,Chinese Academy of Sciences(KXYS20S1501)It is also supported by the National Basic Research Program of China(2014CB846003)China’s QianRen Program and a merit scholarship program for foreign students from Quebec,Canada,to G.Yang.We also thank Dr.Yongheng Gao for providing us the photo of grassland in QTP,and Dr.Mei Wang for her constructive suggestion for im-proving this paper.
文摘Often referred to as the“Third Pole,”China’s Qinghai-Tibetan Plateau developed large amounts of peatland owing to its unique alpine environment.As a renewable resource,peat helps to regulate the climate as well as performing other important functions.However,in recent years,intensifying climate change and anthropogenic disturbances have resulted in peatland degradation and consequently made sustainable development of peatland more difficult.This review summarizes peatland ecological and economic functions,including carbon sequestration,biodiversity conservation,energy supplies,and ecotourism.It identifies climate change and anthropogenic disturbances as the two key factors attributing to peatland degradation and ecosystem carbon loss.Current problems in environmental degradation and future challenges in peatland management under the effects of global warming are also discussed and highlighted.
