In oil and gas exploration,elucidating the complex interdependencies among geological variables is paramount.Our study introduces the application of sophisticated regression analysis method at the forefront,aiming not...In oil and gas exploration,elucidating the complex interdependencies among geological variables is paramount.Our study introduces the application of sophisticated regression analysis method at the forefront,aiming not just at predicting geophysical logging curve values but also innovatively mitigate hydrocarbon depletion observed in geochemical logging.Through a rigorous assessment,we explore the efficacy of eight regression models,bifurcated into linear and nonlinear groups,to accommodate the multifaceted nature of geological datasets.Our linear model suite encompasses the Standard Equation,Ridge Regression,Least Absolute Shrinkage and Selection Operator,and Elastic Net,each presenting distinct advantages.The Standard Equation serves as a foundational benchmark,whereas Ridge Regression implements penalty terms to counteract overfitting,thus bolstering model robustness in the presence of multicollinearity.The Least Absolute Shrinkage and Selection Operator for variable selection functions to streamline models,enhancing their interpretability,while Elastic Net amalgamates the merits of Ridge Regression and Least Absolute Shrinkage and Selection Operator,offering a harmonized solution to model complexity and comprehensibility.On the nonlinear front,Gradient Descent,Kernel Ridge Regression,Support Vector Regression,and Piecewise Function-Fitting methods introduce innovative approaches.Gradient Descent assures computational efficiency in optimizing solutions,Kernel Ridge Regression leverages the kernel trick to navigate nonlinear patterns,and Support Vector Regression is proficient in forecasting extremities,pivotal for exploration risk assessment.The Piecewise Function-Fitting approach,tailored for geological data,facilitates adaptable modeling of variable interrelations,accommodating abrupt data trend shifts.Our analysis identifies Ridge Regression,particularly when augmented by Piecewise Function-Fitting,as superior in recouping hydrocarbon losses,and underscoring its utility in resource quantification refinement.Meanwhile,Kernel Ridge Regression emerges as a noteworthy strategy in ameliorating porosity-logging curve prediction for well A,evidencing its aptness for intricate geological structures.This research attests to the scientific ascendancy and broad-spectrum relevance of these regression techniques over conventional methods while heralding new horizons for their deployment in the oil and gas sector.The insights garnered from these advanced modeling strategies are set to transform geological and engineering practices in hydrocarbon prediction,evaluation,and recovery.展开更多
The problems including excessive flow of attemperating water for boiler, failure of butterfly valve at the outlet of circulating water pump, burnt-out of thyristor for excitation regulator, load variation rate of CCS ...The problems including excessive flow of attemperating water for boiler, failure of butterfly valve at the outlet of circulating water pump, burnt-out of thyristor for excitation regulator, load variation rate of CCS not complying with the contract target, etc. occurred during start-up and debugging of two 600 MW generating units in Yangzhou No.2 Thermal Power Plant. Through analysis on these problems. the remedial measures were put forward, to which can be referred for similar units.展开更多
Objective: The purpose of this study was to address the issues that occur during the B-ultrasound guided peripherally inserted central catheter(PICC) process and to give a summary of the effective management to the...Objective: The purpose of this study was to address the issues that occur during the B-ultrasound guided peripherally inserted central catheter(PICC) process and to give a summary of the effective management to these issues accordingly.Methods: The information was collected retrospectively on all of the 1950 PICCs inserted during the 2-year period from July 2013 to July 2015. PICC catheter insertion was performed using the Seldinger approach and was delivered from the basilic vein to the superior vena cava in a B-ultrasound guided manner. Moreover, the point raised during the PICC process would be treated immediately.Results: All of the PICCs were inserted successfully. The problems encountered are shown in the inserted central catheter(PICC) process, such as failures of venipuncture, the problem of inserting guide wire, the catheter was dif?cult to be delivered etc.Conclusions: The B-ultrasound guided approach enhanced the average success regarding the PICC insertion, particularly for the subset with a poor condition in the elbow super?cial vein. Due to the items that emerged in the PICC process, the effective prevention prior to surgery and treatment during the operation would be necessary.展开更多
In this paper,status quo of water pollution control in the Longgang River Basin is summarized,and the current status of water environment quality is analyzed,and the main problems in water environment management are d...In this paper,status quo of water pollution control in the Longgang River Basin is summarized,and the current status of water environment quality is analyzed,and the main problems in water environment management are discussed.The research aims to provide reference for the management of the Longgang River basin.展开更多
Towards current modern society,our country’s library and information science is not only rapid development,but it also has won the favor of many researchers in more than a decade of development.Due to new technology ...Towards current modern society,our country’s library and information science is not only rapid development,but it also has won the favor of many researchers in more than a decade of development.Due to new technology elements and methods are widely used in the discipline of library and information science,cause society our country’s library and information science has entered a new stage with the development of information industry.This paper is based on the research theory of co-occurrence analysis,clustering co-occurrence analysis of references,social network co-occurrence analysis from researchers and research institutions of the field of library and information science,to have more precise and in depth research on the research focus of the library and information science,the authors themselves and the research institutions circumstances over the past few years.At the same time,the theory is used to analyze the effects and analysis of accurate data,to ensure that researchers can analyze the theory of library and information science for a long time.展开更多
The assets valuation industry in China is the product, which comes from the reform and open policy and the development of the socialist market economy. Under more than 20 years of development which begins to bud in th...The assets valuation industry in China is the product, which comes from the reform and open policy and the development of the socialist market economy. Under more than 20 years of development which begins to bud in the beginning of the nineteen nineties, the assets valuation industry has become the indispensable Intermediary trade of the socialist market economy system in China. With the scale of assets valuation agency enlarging and its rapidly growing business in recent years, however, some problems have been exposed gradually, which harm the social image of the industry of asset valuation seriously. So the social public and the relevant administrative departments pay close attention on the quality of the asset valuation. To know about what are the essential causes that affect the assets valuation industry managers' decision, this paper, through using some means which include literature research, interview and questionnaire investigation and utilizing the method of the factor analysis, relegates 24 questions which come from some answers of the respondents to three factors which are the practicing quality factor, the sting factor of an organization and the internal management factor of valuation organization. Furthermore, it will analyze the features of these factors which are divided into two factors that are internal motivation and external motivation, looking for the key cause of the assets valuation industry quality problem of China which purposes in order to promote the healthy development of valuation profession and much better standard the internal quality of valuation industry of China.展开更多
As agricultural eco-tourism development played a vital role in promoting rural economic and social development and constructing new harmonious countryside,the paper had analyzed environmental problem produced during i...As agricultural eco-tourism development played a vital role in promoting rural economic and social development and constructing new harmonious countryside,the paper had analyzed environmental problem produced during its development,pointed out that blind development of agricultural eco-tourism had seriously destroyed resources and ecological environment and that tourist infrastructure construction and urbanization had ruined rural unique natural landscape.In view of current situation of environment,it also studied reasons causing environmental disruption,which lied in insufficient guidance and support of government,deficient scientific development planning and management system,and poor environmental consciousness of tourist operators and tourists.On this basis,it summarized that agricultural eco-tourism development should follow principles of sustainable development,synchronization between development and protection,and coordination between tourism development and environmental protection.It concluded proper ways to develop agricultural eco-tourism,and emphasized that it should draw up scientific and reasonable development planning,enhance government's macro-administration,establish and perfect ecological compensation mechanism,and strive to cultivate people's environmental awareness.展开更多
With the rapid development of social economy,the sense of urgency among enterprises is increasing.The primary reason for this is the fierce competition among enterprises.As an important strategy for establishing a mod...With the rapid development of social economy,the sense of urgency among enterprises is increasing.The primary reason for this is the fierce competition among enterprises.As an important strategy for establishing a modern enterprise system,asset restructuring plays a pivotal role in improving the economic efficiency of enterprises,optimizing the allocation of social resources,and promoting both,social and economic development.Therefore,based on the existing problems of enterprise asset restructuring accounting,this paper discusses the causes of the accounting deficiencies in enterprise asset restructuring from various perspectives,including asset restructuring concept,financial authority and responsibility authority,as well as commercial credit,and subsequently proposes corresponding optimization strategies,which include strengthening asset valuation,enhancing information disclosure of connected transactions,improving relevant accounting standards,as well as strengthening information audit and improving related systems.展开更多
Based on lawn function theory and urban planning perspectives, functions of urban lawns were analyzed, status and prospect of the multiple usages of lawn were revealed. Urban lawn was concluded as an important part of...Based on lawn function theory and urban planning perspectives, functions of urban lawns were analyzed, status and prospect of the multiple usages of lawn were revealed. Urban lawn was concluded as an important part of modern urban greening, moveover, it has been integrated in people's lives gradually by playing a significant role in people's work, studying, leisure, urban disaster prevention and mitigation. At the same time, problems rise from the multiple usages of lawn were discussed and improvement suggestions were put forward.展开更多
The author interpreted the video The Art of Negotiation of Stanford University. In the interpreting process, the interpreter encounters some listening obstacles. Through analyzing the listening problems in the task,th...The author interpreted the video The Art of Negotiation of Stanford University. In the interpreting process, the interpreter encounters some listening obstacles. Through analyzing the listening problems in the task,the author has realized the weakness in interpreting. With the help of the relevance theory,the interpreter comes up with corresponding strategies, gives an analysis of the listening problems encountered in the interpreting process and makes a reflection on the interpreting in order to enhance the interpreting skills.展开更多
Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quan...Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quantum mechanics and value problems.In this paper,we first give the definition of a quasi-Cauchy type integral in complex Clifford analysis,and get the Plemelj formula for it.Second,we discuss the H?lder continuity for the Cauchy-type integral operators with values in a complex Clifford algebra.Finally,we prove the existence of solutions for a class of linear boundary value problems and give the integral representation for the solution.展开更多
For the large sparse saddle point problems, Pan and Li recently proposed in [H. K. Pan, W. Li, Math. Numer. Sinica, 2009, 31(3): 231-242] a corrected Uzawa algorithm based on a nonlinear Uzawa algorithm with two no...For the large sparse saddle point problems, Pan and Li recently proposed in [H. K. Pan, W. Li, Math. Numer. Sinica, 2009, 31(3): 231-242] a corrected Uzawa algorithm based on a nonlinear Uzawa algorithm with two nonlinear approximate inverses, and gave the detailed convergence analysis. In this paper, we focus on the convergence analysis of this corrected Uzawa algorithm, some inaccuracies in [H. K. Pan, W. Li, Math. Numer. Sinica, 2009, 31(3): 231-242] are pointed out, and a corrected convergence theorem is presented. A special case of this modified Uzawa algorithm is also discussed.展开更多
A new algorithm for the solution of quadratic programming problemsis put forward in terms of the mixed energy theory and is furtherused for the incremental solution of elastic-plastic trussstructures. The method propo...A new algorithm for the solution of quadratic programming problemsis put forward in terms of the mixed energy theory and is furtherused for the incremental solution of elastic-plastic trussstructures. The method proposed is different from the traditionalone, for which the unknown variables are selected just in one classsuch as displacements or stresses. The present method selects thevariables in the mixed form with both displacement and stress. As themethod is established in the hybrid space, the information found inthe previous incremental step can be used for the solution of thepresent step, making the algorithm highly effi- cient in thenumerical solution process of quadratic programming problems. Theresults obtained in the exm- ples of the elastic-plastic solution ofthe truss structures verify what has been predicted in thetheoretical anal- ysis.展开更多
To accelerate the achievement of China’s carbon neutrality goal and to study the factors affecting the geologic CO_(2)storage in the Ordos Basin,China’s National Key R&D Programs propose to select the Chang 6 oi...To accelerate the achievement of China’s carbon neutrality goal and to study the factors affecting the geologic CO_(2)storage in the Ordos Basin,China’s National Key R&D Programs propose to select the Chang 6 oil reservoir of the Yanchang Formation in the Ordos Basin as the target reservoir to conduct the geologic carbon capture and storage(CCS)of 100000 t per year.By applying the basic theories of disciplines such as seepage mechanics,multiphase fluid mechanics,and computational fluid mechanics and quantifying the amounts of CO_(2)captured in gas and dissolved forms,this study investigated the effects of seven factors that influence the CO_(2)storage capacity of reservoirs,namely reservoir porosity,horizontal permeability,temperature,formation stress,the ratio of vertical to horizontal permeability,capillary pressure,and residual gas saturation.The results show that the sensitivity of the factors affecting the gas capture capacity of CO_(2)decreases in the order of formation stress,temperature,residual gas saturation,horizontal permeability,and porosity.Meanwhile,the sensitivity of the factors affecting the dissolution capture capacity of CO_(2)decreases in the order of formation stress,residual gas saturation,temperature,horizontal permeability,and porosity.The sensitivity of the influencing factors can serve as the basis for carrying out a reasonable assessment of sites for future CO_(2)storage areas and for optimizing the design of existing CO_(2)storage areas.The sensitivity analysis of the influencing factors will provide basic data and technical support for implementing geologic CO_(2)storage and will assist in improving geologic CO_(2)storage technologies to achieve China’s carbon neutralization goal.展开更多
The solution of a slope stability problem can be approached by its least upper-bound and maximum lower-bound with high accuracy. The limit equilibrium methods that employ vertical slices imply a lower bound of the fac...The solution of a slope stability problem can be approached by its least upper-bound and maximum lower-bound with high accuracy. The limit equilibrium methods that employ vertical slices imply a lower bound of the factor of safety. It has been successfully extended to the area of active earth pressure analysis that accounts for different input of locations of earth pressure applications. Those methods that employ slices with inclined interfaces give an upper-bound approach to the stability analysis. It enjoys a sound mechanical background and is able to provide accurate solutions of soil plasticity. It has been successfully extended to the area of bearing capacity analysis in which various empirical coefficients are no longer necessary. The 3D upper- and lower-bound methods under this framework have been made possible and show great potential for solving various engineering problems.展开更多
Intensive curing barn is an important component of flue-cured tobacco pro-duction in China, with progress made. However, problems stil exist, such as lower heat energy utilization efficiency and slow equipment update....Intensive curing barn is an important component of flue-cured tobacco pro-duction in China, with progress made. However, problems stil exist, such as lower heat energy utilization efficiency and slow equipment update. In the research, opti-mization ways of tobacco barn were analyzed in flue-cured tobacco production re-gions, and assessment was made on improvement effects, in order to provide refer-ences for highly-efficient and low-carbon development of curing barn.展开更多
Background: Common bile duct (CBD) stones may occur in up to 3%–14.7% of all patients with cholecystectomy.Various approaches of laparoscopic CBD exploration plus primary duct closure (PDC) are the most commonly...Background: Common bile duct (CBD) stones may occur in up to 3%–14.7% of all patients with cholecystectomy.Various approaches of laparoscopic CBD exploration plus primary duct closure (PDC) are the most commonly used and the best methods to treat CBD stone. This systematic review was to comparethe effectiveness and safety of the various approaches of laparoscopic CBD exploration plus PDC forcholedocholithiasis展开更多
Bangladesh is a land of wetlands. Basically, most of them are freshwater wetlands and have great influence on the primary economic activities such as agriculture and fisheries of the country. Due to its important role...Bangladesh is a land of wetlands. Basically, most of them are freshwater wetlands and have great influence on the primary economic activities such as agriculture and fisheries of the country. Due to its important role in the harmonizing ecosystem, wetlands demand much attention as a significant part of our environment. Matasagar and Sukhsagar are very important historical wetlands of Bangladesh. But those are endangered today due to lack of public awareness of the dangers of their activities to the environment and unbridled profit making activities of the commercial users of the wetlands. Comparisons of maps and Google images from 1933 to present have shown that the forest areas of the wetlands have been progressively destroyed, and these have greatly affected the biodiversity of these areas mentioned. GIS (Geographic Information System) and remote sensing techniques are used to identify the changes in the aerial extent of those wetlands. This study also tried to explore present environmental conditions by in-situ observation. This is high time;some serious steps should be taken to ensure the conservation and preservation of these areas mentioned.展开更多
There is no question that Computer Assisted Language Learning(CALL) has been a feature of teaching and learning in college.CALL plays a significant role in second language teaching.This article will focus on an overvi...There is no question that Computer Assisted Language Learning(CALL) has been a feature of teaching and learning in college.CALL plays a significant role in second language teaching.This article will focus on an overview of three different types of roles of CALL to demonstrate its application in Chinese college English teaching.展开更多
The main technical requirement of the turbine generating units for the Three Gorges Project (TGP) has a basic conclusion through a long term study and research as well as demonstration.Along with the TGP construction ...The main technical requirement of the turbine generating units for the Three Gorges Project (TGP) has a basic conclusion through a long term study and research as well as demonstration.Along with the TGP construction and successful execution of the contract of turbine generating units,the technical difficulties concerning the performance and structure of turbine generating units have been further recognized.In this paper some issues are discussed and analyzed in connection with a deep going cognition of turbine generating units for TGP during the period of design, manufacture and installation.展开更多
文摘In oil and gas exploration,elucidating the complex interdependencies among geological variables is paramount.Our study introduces the application of sophisticated regression analysis method at the forefront,aiming not just at predicting geophysical logging curve values but also innovatively mitigate hydrocarbon depletion observed in geochemical logging.Through a rigorous assessment,we explore the efficacy of eight regression models,bifurcated into linear and nonlinear groups,to accommodate the multifaceted nature of geological datasets.Our linear model suite encompasses the Standard Equation,Ridge Regression,Least Absolute Shrinkage and Selection Operator,and Elastic Net,each presenting distinct advantages.The Standard Equation serves as a foundational benchmark,whereas Ridge Regression implements penalty terms to counteract overfitting,thus bolstering model robustness in the presence of multicollinearity.The Least Absolute Shrinkage and Selection Operator for variable selection functions to streamline models,enhancing their interpretability,while Elastic Net amalgamates the merits of Ridge Regression and Least Absolute Shrinkage and Selection Operator,offering a harmonized solution to model complexity and comprehensibility.On the nonlinear front,Gradient Descent,Kernel Ridge Regression,Support Vector Regression,and Piecewise Function-Fitting methods introduce innovative approaches.Gradient Descent assures computational efficiency in optimizing solutions,Kernel Ridge Regression leverages the kernel trick to navigate nonlinear patterns,and Support Vector Regression is proficient in forecasting extremities,pivotal for exploration risk assessment.The Piecewise Function-Fitting approach,tailored for geological data,facilitates adaptable modeling of variable interrelations,accommodating abrupt data trend shifts.Our analysis identifies Ridge Regression,particularly when augmented by Piecewise Function-Fitting,as superior in recouping hydrocarbon losses,and underscoring its utility in resource quantification refinement.Meanwhile,Kernel Ridge Regression emerges as a noteworthy strategy in ameliorating porosity-logging curve prediction for well A,evidencing its aptness for intricate geological structures.This research attests to the scientific ascendancy and broad-spectrum relevance of these regression techniques over conventional methods while heralding new horizons for their deployment in the oil and gas sector.The insights garnered from these advanced modeling strategies are set to transform geological and engineering practices in hydrocarbon prediction,evaluation,and recovery.
文摘The problems including excessive flow of attemperating water for boiler, failure of butterfly valve at the outlet of circulating water pump, burnt-out of thyristor for excitation regulator, load variation rate of CCS not complying with the contract target, etc. occurred during start-up and debugging of two 600 MW generating units in Yangzhou No.2 Thermal Power Plant. Through analysis on these problems. the remedial measures were put forward, to which can be referred for similar units.
文摘Objective: The purpose of this study was to address the issues that occur during the B-ultrasound guided peripherally inserted central catheter(PICC) process and to give a summary of the effective management to these issues accordingly.Methods: The information was collected retrospectively on all of the 1950 PICCs inserted during the 2-year period from July 2013 to July 2015. PICC catheter insertion was performed using the Seldinger approach and was delivered from the basilic vein to the superior vena cava in a B-ultrasound guided manner. Moreover, the point raised during the PICC process would be treated immediately.Results: All of the PICCs were inserted successfully. The problems encountered are shown in the inserted central catheter(PICC) process, such as failures of venipuncture, the problem of inserting guide wire, the catheter was dif?cult to be delivered etc.Conclusions: The B-ultrasound guided approach enhanced the average success regarding the PICC insertion, particularly for the subset with a poor condition in the elbow super?cial vein. Due to the items that emerged in the PICC process, the effective prevention prior to surgery and treatment during the operation would be necessary.
文摘In this paper,status quo of water pollution control in the Longgang River Basin is summarized,and the current status of water environment quality is analyzed,and the main problems in water environment management are discussed.The research aims to provide reference for the management of the Longgang River basin.
文摘Towards current modern society,our country’s library and information science is not only rapid development,but it also has won the favor of many researchers in more than a decade of development.Due to new technology elements and methods are widely used in the discipline of library and information science,cause society our country’s library and information science has entered a new stage with the development of information industry.This paper is based on the research theory of co-occurrence analysis,clustering co-occurrence analysis of references,social network co-occurrence analysis from researchers and research institutions of the field of library and information science,to have more precise and in depth research on the research focus of the library and information science,the authors themselves and the research institutions circumstances over the past few years.At the same time,the theory is used to analyze the effects and analysis of accurate data,to ensure that researchers can analyze the theory of library and information science for a long time.
文摘The assets valuation industry in China is the product, which comes from the reform and open policy and the development of the socialist market economy. Under more than 20 years of development which begins to bud in the beginning of the nineteen nineties, the assets valuation industry has become the indispensable Intermediary trade of the socialist market economy system in China. With the scale of assets valuation agency enlarging and its rapidly growing business in recent years, however, some problems have been exposed gradually, which harm the social image of the industry of asset valuation seriously. So the social public and the relevant administrative departments pay close attention on the quality of the asset valuation. To know about what are the essential causes that affect the assets valuation industry managers' decision, this paper, through using some means which include literature research, interview and questionnaire investigation and utilizing the method of the factor analysis, relegates 24 questions which come from some answers of the respondents to three factors which are the practicing quality factor, the sting factor of an organization and the internal management factor of valuation organization. Furthermore, it will analyze the features of these factors which are divided into two factors that are internal motivation and external motivation, looking for the key cause of the assets valuation industry quality problem of China which purposes in order to promote the healthy development of valuation profession and much better standard the internal quality of valuation industry of China.
基金Supported by Part of Research Results of Special Program of Humane Social Science Fund of Guizhou Education Department(09ZX084)~~
文摘As agricultural eco-tourism development played a vital role in promoting rural economic and social development and constructing new harmonious countryside,the paper had analyzed environmental problem produced during its development,pointed out that blind development of agricultural eco-tourism had seriously destroyed resources and ecological environment and that tourist infrastructure construction and urbanization had ruined rural unique natural landscape.In view of current situation of environment,it also studied reasons causing environmental disruption,which lied in insufficient guidance and support of government,deficient scientific development planning and management system,and poor environmental consciousness of tourist operators and tourists.On this basis,it summarized that agricultural eco-tourism development should follow principles of sustainable development,synchronization between development and protection,and coordination between tourism development and environmental protection.It concluded proper ways to develop agricultural eco-tourism,and emphasized that it should draw up scientific and reasonable development planning,enhance government's macro-administration,establish and perfect ecological compensation mechanism,and strive to cultivate people's environmental awareness.
文摘With the rapid development of social economy,the sense of urgency among enterprises is increasing.The primary reason for this is the fierce competition among enterprises.As an important strategy for establishing a modern enterprise system,asset restructuring plays a pivotal role in improving the economic efficiency of enterprises,optimizing the allocation of social resources,and promoting both,social and economic development.Therefore,based on the existing problems of enterprise asset restructuring accounting,this paper discusses the causes of the accounting deficiencies in enterprise asset restructuring from various perspectives,including asset restructuring concept,financial authority and responsibility authority,as well as commercial credit,and subsequently proposes corresponding optimization strategies,which include strengthening asset valuation,enhancing information disclosure of connected transactions,improving relevant accounting standards,as well as strengthening information audit and improving related systems.
文摘Based on lawn function theory and urban planning perspectives, functions of urban lawns were analyzed, status and prospect of the multiple usages of lawn were revealed. Urban lawn was concluded as an important part of modern urban greening, moveover, it has been integrated in people's lives gradually by playing a significant role in people's work, studying, leisure, urban disaster prevention and mitigation. At the same time, problems rise from the multiple usages of lawn were discussed and improvement suggestions were put forward.
文摘The author interpreted the video The Art of Negotiation of Stanford University. In the interpreting process, the interpreter encounters some listening obstacles. Through analyzing the listening problems in the task,the author has realized the weakness in interpreting. With the help of the relevance theory,the interpreter comes up with corresponding strategies, gives an analysis of the listening problems encountered in the interpreting process and makes a reflection on the interpreting in order to enhance the interpreting skills.
基金supported by the NSF of Hebei Province(A2022208007)the NSF of China(11571089,11871191)the NSF of Henan Province(222300420397)。
文摘Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quantum mechanics and value problems.In this paper,we first give the definition of a quasi-Cauchy type integral in complex Clifford analysis,and get the Plemelj formula for it.Second,we discuss the H?lder continuity for the Cauchy-type integral operators with values in a complex Clifford algebra.Finally,we prove the existence of solutions for a class of linear boundary value problems and give the integral representation for the solution.
基金Supported by the National Natural Science Foundation of China(11201422)the Natural Science Foundation of Zhejiang Province(Y6110639,LQ12A01017)
文摘For the large sparse saddle point problems, Pan and Li recently proposed in [H. K. Pan, W. Li, Math. Numer. Sinica, 2009, 31(3): 231-242] a corrected Uzawa algorithm based on a nonlinear Uzawa algorithm with two nonlinear approximate inverses, and gave the detailed convergence analysis. In this paper, we focus on the convergence analysis of this corrected Uzawa algorithm, some inaccuracies in [H. K. Pan, W. Li, Math. Numer. Sinica, 2009, 31(3): 231-242] are pointed out, and a corrected convergence theorem is presented. A special case of this modified Uzawa algorithm is also discussed.
基金the National Natural Science Foundation of China(No.50178916,No.19732020 and No.19872016)the National Key Basic lteseareh Special Foundation(No.G1999032805)+1 种基金the Special Funds for Major State Basic Researeh Projectsthe Foundation for University Key Teachers by the Ministry of Education of China
文摘A new algorithm for the solution of quadratic programming problemsis put forward in terms of the mixed energy theory and is furtherused for the incremental solution of elastic-plastic trussstructures. The method proposed is different from the traditionalone, for which the unknown variables are selected just in one classsuch as displacements or stresses. The present method selects thevariables in the mixed form with both displacement and stress. As themethod is established in the hybrid space, the information found inthe previous incremental step can be used for the solution of thepresent step, making the algorithm highly effi- cient in thenumerical solution process of quadratic programming problems. Theresults obtained in the exm- ples of the elastic-plastic solution ofthe truss structures verify what has been predicted in thetheoretical anal- ysis.
基金jointly supported by the National Key R&D Program of China (2018YFB0605503)the National Natural Science Foundation of China (51804112)+2 种基金the National Key R&D Program of China (2018YFC0807801)the Open Foundation of Key Laboratory of Coal Exploration and Comprehensive Utilization of Ministry of Natural Resources (KF2021-5)the Natural Science Foundation of Hunan Province of China (2018JJ3169).
文摘To accelerate the achievement of China’s carbon neutrality goal and to study the factors affecting the geologic CO_(2)storage in the Ordos Basin,China’s National Key R&D Programs propose to select the Chang 6 oil reservoir of the Yanchang Formation in the Ordos Basin as the target reservoir to conduct the geologic carbon capture and storage(CCS)of 100000 t per year.By applying the basic theories of disciplines such as seepage mechanics,multiphase fluid mechanics,and computational fluid mechanics and quantifying the amounts of CO_(2)captured in gas and dissolved forms,this study investigated the effects of seven factors that influence the CO_(2)storage capacity of reservoirs,namely reservoir porosity,horizontal permeability,temperature,formation stress,the ratio of vertical to horizontal permeability,capillary pressure,and residual gas saturation.The results show that the sensitivity of the factors affecting the gas capture capacity of CO_(2)decreases in the order of formation stress,temperature,residual gas saturation,horizontal permeability,and porosity.Meanwhile,the sensitivity of the factors affecting the dissolution capture capacity of CO_(2)decreases in the order of formation stress,residual gas saturation,temperature,horizontal permeability,and porosity.The sensitivity of the influencing factors can serve as the basis for carrying out a reasonable assessment of sites for future CO_(2)storage areas and for optimizing the design of existing CO_(2)storage areas.The sensitivity analysis of the influencing factors will provide basic data and technical support for implementing geologic CO_(2)storage and will assist in improving geologic CO_(2)storage technologies to achieve China’s carbon neutralization goal.
基金Project (Nos. 50539100,50679035 and 50509027) supported by the National Natural ScienceFoundation of China
文摘The solution of a slope stability problem can be approached by its least upper-bound and maximum lower-bound with high accuracy. The limit equilibrium methods that employ vertical slices imply a lower bound of the factor of safety. It has been successfully extended to the area of active earth pressure analysis that accounts for different input of locations of earth pressure applications. Those methods that employ slices with inclined interfaces give an upper-bound approach to the stability analysis. It enjoys a sound mechanical background and is able to provide accurate solutions of soil plasticity. It has been successfully extended to the area of bearing capacity analysis in which various empirical coefficients are no longer necessary. The 3D upper- and lower-bound methods under this framework have been made possible and show great potential for solving various engineering problems.
文摘Intensive curing barn is an important component of flue-cured tobacco pro-duction in China, with progress made. However, problems stil exist, such as lower heat energy utilization efficiency and slow equipment update. In the research, opti-mization ways of tobacco barn were analyzed in flue-cured tobacco production re-gions, and assessment was made on improvement effects, in order to provide refer-ences for highly-efficient and low-carbon development of curing barn.
基金supported by a grant from the Research Program for Health Care of Lanzhou Science and Technology Bureau(No.2013-3-37)
文摘Background: Common bile duct (CBD) stones may occur in up to 3%–14.7% of all patients with cholecystectomy.Various approaches of laparoscopic CBD exploration plus primary duct closure (PDC) are the most commonly used and the best methods to treat CBD stone. This systematic review was to comparethe effectiveness and safety of the various approaches of laparoscopic CBD exploration plus PDC forcholedocholithiasis
文摘Bangladesh is a land of wetlands. Basically, most of them are freshwater wetlands and have great influence on the primary economic activities such as agriculture and fisheries of the country. Due to its important role in the harmonizing ecosystem, wetlands demand much attention as a significant part of our environment. Matasagar and Sukhsagar are very important historical wetlands of Bangladesh. But those are endangered today due to lack of public awareness of the dangers of their activities to the environment and unbridled profit making activities of the commercial users of the wetlands. Comparisons of maps and Google images from 1933 to present have shown that the forest areas of the wetlands have been progressively destroyed, and these have greatly affected the biodiversity of these areas mentioned. GIS (Geographic Information System) and remote sensing techniques are used to identify the changes in the aerial extent of those wetlands. This study also tried to explore present environmental conditions by in-situ observation. This is high time;some serious steps should be taken to ensure the conservation and preservation of these areas mentioned.
文摘There is no question that Computer Assisted Language Learning(CALL) has been a feature of teaching and learning in college.CALL plays a significant role in second language teaching.This article will focus on an overview of three different types of roles of CALL to demonstrate its application in Chinese college English teaching.
文摘The main technical requirement of the turbine generating units for the Three Gorges Project (TGP) has a basic conclusion through a long term study and research as well as demonstration.Along with the TGP construction and successful execution of the contract of turbine generating units,the technical difficulties concerning the performance and structure of turbine generating units have been further recognized.In this paper some issues are discussed and analyzed in connection with a deep going cognition of turbine generating units for TGP during the period of design, manufacture and installation.