Road and bridge engineering is an indispensable part of socialist economic construction in China, whose construction quality significantly affects the infrastructure construction level in the whole society. To meet th...Road and bridge engineering is an indispensable part of socialist economic construction in China, whose construction quality significantly affects the infrastructure construction level in the whole society. To meet the rapid economic development of various regions, construction scale and quantity of road and bridge engineering have been continuously expanded and increased, therefore, higher requirements for construction quality and construction standard are also presented. During the construction of road and bridge engineering, concrete crack is a key problem which affects the construction quality. In this regard, this paper analyzes cause and prevention measures of concrete cracks during the construction of road and bridge engineering, and hopes to provide construction personnel with valuable references.展开更多
With the continuous development of economy and society, people's ability to transform society has been improved. To break the constraints of hydrological and climatic conditions, some hydrology and water conservan...With the continuous development of economy and society, people's ability to transform society has been improved. To break the constraints of hydrological and climatic conditions, some hydrology and water conservancy projects were constructed to meet the needs of human activities. In the construction of hydrological engineering, geological conditions are first surveyed to determine whether there are significant geological structure problems, in order to enhance the stability of hydrological engineering and reduce the probability of hydrological engineering leakage.展开更多
For engineering geological investigation, hydrographic surveys are particularly important. By operating the equipment, relevant technicians analyze hydrogeological data around the project. A series of corresponding me...For engineering geological investigation, hydrographic surveys are particularly important. By operating the equipment, relevant technicians analyze hydrogeological data around the project. A series of corresponding measures were taken to ensure the smooth completion of the project. However, due to the inadequate completion of hydrogeological survey work, it has great harm to the later stage of engineering work, and even will lead to the final failure of the project. Based on this, this paper explores the hazards and prevention measures of hydrogeology in engineering surveys.展开更多
With the rapid development of the social economy,people are paying more and more attention to environmental issues.If society wants sustainable development,it must put energy conservation and emission reduction on the...With the rapid development of the social economy,people are paying more and more attention to environmental issues.If society wants sustainable development,it must put energy conservation and emission reduction on the agenda.At this stage,China has vigorously promoted energy conservation and emission reduction,and all walks of life have gradually embarked on the green road of energy conservation.In recent years,energy saving measures has been widely used in China's oilfield electrical engineering.The author explores and analyzes the basic principles of energy saving measures applied in oilfield electrical engineering,and proposes an effective way to apply energy saving measures in oilfield electrical engineering,hoping to contribute to the energy saving effect of oilfield electrical engineering.展开更多
Building decoration engineering mainly carries out various decoration works for buildings,which can provide protection for building components,avoid the influence of nature as far as possible,and help to improve the f...Building decoration engineering mainly carries out various decoration works for buildings,which can provide protection for building components,avoid the influence of nature as far as possible,and help to improve the function of buildings and prolong their life.At the same time,the building decoration project is an important part of the whole construction project,and the probability of bad situation is relatively large,so it is necessary to carry out in-depth exploration for the corresponding management work,clarify the existing problems,and put forward corresponding measures according to the actual situation.展开更多
The air quality of the ecological enviro-nment is closely related to people's health.However,due to the rapid economic development in recent years,it has indirectly led to the continuous deterioration of the quali...The air quality of the ecological enviro-nment is closely related to people's health.However,due to the rapid economic development in recent years,it has indirectly led to the continuous deterioration of the quality of the atmospheric environment.Effective control of air pollution in environmental engineering is an important measure to improve the ecological environment and the quality of people’s lives.Therefore,this paper combines the main causes and hazards of air pollution to analyze environmental protection measures in-depth.展开更多
Deep foundation pit excavation is a basic and key step involved in modern building construction.In order to ensure the construction quality and safety of deep foundation pits,this paper takes a project as an example t...Deep foundation pit excavation is a basic and key step involved in modern building construction.In order to ensure the construction quality and safety of deep foundation pits,this paper takes a project as an example to analyze deep foundation pit excavation technology,including the nature of this construction project,the main technical measures in the construction of deep foundation pit,and the analysis of the safety risk prevention and control measures.The purpose of this analysis is to provide scientific reference for the construction quality and safety of deep foundation pits.展开更多
The principle of sonic wave measurement was introduced, and cumulative damage effects of underground engineering rock mass under blasting load were studied by in situ test, using RSM-SY5 intelligent sonic wave apparat...The principle of sonic wave measurement was introduced, and cumulative damage effects of underground engineering rock mass under blasting load were studied by in situ test, using RSM-SY5 intelligent sonic wave apparatus. The blasting test was carried out for ten times at some tunnels of Changba Lead-Zinc Mine. The damage depth of surrounding rock caused by old blasting excavation (0.8-1.2 m) was confirmed. The relation between the cumulative damage degree and blast times was obtained. The results show that the sonic velocity decreases gradually with increasing blast times, hut the damage degree (D) increases. The damage cumulative law is non-linear. The damage degree caused by blast decreases with increasing distance, and damage effects become indistinct. The blasting damage of rock mass is anisotropic. The damage degree of rock mass within charging range is maximal. And the more the charge is, the more severe the damage degree of rock mass is. The test results provide references for researches of mechanical parameters of rock mass and dynamic stability analysis of underground chambers.展开更多
Acquisition of physical data with high precision is a key step in reverse engineering (RE). It is an important stimulative for the progress of reverse engineering with which various digitizing devices are invent ed,...Acquisition of physical data with high precision is a key step in reverse engineering (RE). It is an important stimulative for the progress of reverse engineering with which various digitizing devices are invent ed, developed and made applicable. This paper introduces a three dimensional opt ical measurement method based on digital fringe projection technique in RE to im prove the technique through its application. A practical example is presented an d the result demonstrates the applicability and feasibility of the measurement s ystem as well as the reliability and validity of relevant methods and algorithms .展开更多
This article attempts to investigate the measure effect of rubble roadbed engineering in permafrost regions of Qinghai-Tibet Plateau. As a case study, Chaidaer-Muli Railway is used to evaluate the measure effect of ru...This article attempts to investigate the measure effect of rubble roadbed engineering in permafrost regions of Qinghai-Tibet Plateau. As a case study, Chaidaer-Muli Railway is used to evaluate the measure effect of rubble roadbed engineering in permafrost regions. The AHP(Analytic Hierarchy Process) method is thus employed to establish the evaluation indicator system. The evaluation factor is selected by analyzing the mutual relation between the permafrost environment and roadbed engineering. Thus, a hierarchical structure model is established based on the selected evaluation indices. Each factor is weighted to determine the status in the evaluation system, and grading standards are built for providing a basis for the evaluation. Then, the fuzzy mathematical method is introduced to evaluate the measure effect of rubble roadbed engineering in permafrost regions along the Chadaer-Muli Railway. Results show that most of the permafrost roadbed is in a preferable condition(b) along the Chaidaer-Muli Railway due to rubble engineering measures. This proportion reaches to 86.1%. The proportion in good(a), general(c) and poor states(d) are 0.0%, 7.5% and 6.4%, respectively, in all the evaluation sections along the Chaidaer-Muli Railway. Ground-temperature monitoring results are generally consistent with AHP-FUZZY evaluation results. This means that the AHP-FUZZY method can be applied to evaluate the effect of rubble roadbed engineering measures in permafrost regions. The effect evaluation of engineering measures will provide timely and effective feedback information for further engineering design. The series of engineering measures will more effectively protect permafrost stability.展开更多
Data were collected from Three-north Region, Middle and upper reaches region of Yangtze River and Coastal region. By analysis of factors influencing soil erosion, the longitude, latitude, annual precipitation, and the...Data were collected from Three-north Region, Middle and upper reaches region of Yangtze River and Coastal region. By analysis of factors influencing soil erosion, the longitude, latitude, annual precipitation, and the slope degree were selected as regional independent variables and canopy density and stock litter were selected as independent variables, and integral diffusing models were established for evaluation of the benefit of soil and water conservation of forest. By solving the parameters of models using the package of STATISTICA, the Power function between independent variables and dependent variables was set up. The soil conservation amount of forest and economic values were estimated using the contrast method for the ecological forestry engineering of the above three areas.展开更多
The intake swirl in the cylinder was induced by a swirler which was fixed in one of two intake ports. In order to understand the characteristics of the intake swirl, a transparent water analog was designed which simul...The intake swirl in the cylinder was induced by a swirler which was fixed in one of two intake ports. In order to understand the characteristics of the intake swirl, a transparent water analog was designed which simulated 150 type single cylinder engine. At the same time, the particle image velocimetry was used to measure the flow fields induced by various swirlers in the analog. After measurement, a new method was presented to evaluate the intensity of the intake swirl. Then, when the measured sections, the lifts of valve and the swirlers were different, the calculated results of the flow field were compared.展开更多
Chaohu Lake, located in the central Anhui Province, is one of the five largest fresh lakes in China. Now it is one of the three most eutrophication lakes in China. The deterioration of its water quality has influenced...Chaohu Lake, located in the central Anhui Province, is one of the five largest fresh lakes in China. Now it is one of the three most eutrophication lakes in China. The deterioration of its water quality has influenced the sustainable development of society, economy and environment of Hefei City, the capital of Anhui Province. A series of measures have been carried out to control its eutrophication, but it is still serious. On the basis of the lake water quality data from 1984 to 2003, the causes of the eutrophication of Chaohu Lake are analyzed. Studies indicated that the suitable natural conditions and human activities played a crucial role in the process of the eutrophication of Chaohu Lake. A great amount of industrial, agricultural and domestic sewage discharged into the lake is the main cause of eutrophication in the lake. Land use, soil erosion and shoreline collapse destroyed the watershed eco-environment and the terrestrial ecosystem of Chaohu Lake. And the building of Yuxi Gate extends the sluggish of the nutritious substance and speeds up the process of the eutrophication. From the view of systematic engineering and watershed ecology, a series of the countermeasures have been put forward to control the eutrophication.展开更多
Ground-motion Intensity Measures (IMs) are used to quantify the strength of ground motions and evaluate the response of structures. IMs act as a link between seismic demand and seismic hazard analysis and therefore, h...Ground-motion Intensity Measures (IMs) are used to quantify the strength of ground motions and evaluate the response of structures. IMs act as a link between seismic demand and seismic hazard analysis and therefore, have a key role in performance-based earthquake engineering. Many studies have been carried out on the determination of suitable IMs in terms of effi ciency, suffi ciency and scaling robustness. The majority of these investigations focused on ordinary structures such as buildings and bridges, and only a few were about buried pipelines. In the current study, the optimal IMs for predicting the seismic demand of continuous buried steel pipelines under near-fi eld pulse-like ground motion records is investigated. Incremental dynamic analysis is performed using twenty ground motion records. Using the results of the regression analysis, the optimality of 23 potential IMs are studied. It is concluded that specifi c energy density (SED) followed by VSI[ω1(PGD+RMSd )] are the optimal IMs based on effi ciency, suffi ciency and scaling robustness for seismic response evaluation of buried pipelines under near-fi eld ground motions.展开更多
ITER magnet gravity support (GS) has been redesigned as a structure of pre- assembled nmlti-flexible plates instead of the original welded structure. In the past several years, engineering tests of the new structure...ITER magnet gravity support (GS) has been redesigned as a structure of pre- assembled nmlti-flexible plates instead of the original welded structure. In the past several years, engineering tests of the new structure have been proposed. A prototype engineering test plat- form is being developed. In order to apply the loads/load combinations onto the test mock-up, seven hydraulic bolt tensioners in three directions have been applied to simulate various loads (forces and moments), through which the deformation of bolts, flexible plates and clamp blocks, the stress distribution in the flexible plates, the friction between the contact surface, etc. can be monitored/tested. The measurement and control system includes seven sets of synchronization controller, a 16-channel strain gauge, 25 sets of displacement sensors, etc. Principles of EDC220 digital controller and development of multi-channel control software are also demonstrated.展开更多
An improved multidirectional velocity model was proposed for more accurately locating micro-seismic events in rock engineering. It was assumed that the stress wave propagation velocities from a micro-seismic source to...An improved multidirectional velocity model was proposed for more accurately locating micro-seismic events in rock engineering. It was assumed that the stress wave propagation velocities from a micro-seismic source to three nearest monitoring sensors in a sensor's array arrangement were the same. Since the defined objective function does not require pre-measurement of the stress wave propagation velocity in the field, errors from the velocity measurement can be avoided in comparison to three traditional velocity models. By analyzing 24 different cases, the proposed multidirectional velocity model iterated by the Simplex method is found to be the best option no matter the source is within the region of the sensor's array or not. The proposed model and the adopted iterative algorithm are verified by field data and it is concluded that it can significantly reduce the error of the estimated source location.展开更多
Under the premise of building an innovation-oriented country and cultivating new engineering innovative talents, how to carry out the teaching of professional innovative learning, cultivate the innovative thinking of ...Under the premise of building an innovation-oriented country and cultivating new engineering innovative talents, how to carry out the teaching of professional innovative learning, cultivate the innovative thinking of the students, and improve the teaching mode and the curriculum form have become the main directions for deepening the reform of higher education. This article analyses the main problems existing in cultivating new engineering innovative talents for college students, probes into solutions, puts forward teaching methods and gives evaluation methods. The use of CDIO, innovative practice, combining production, learning and research methods to improve students' innovative abilities, practice shows that the exploration of reform can get a good training effect.展开更多
Compared with traditional bank protection, ecological revetments, as a new type of bank protection, can ensure the sustainable and healthy development of river ecology and has broad application prospects. In this pape...Compared with traditional bank protection, ecological revetments, as a new type of bank protection, can ensure the sustainable and healthy development of river ecology and has broad application prospects. In this paper, the design principles for ecological revetments and the factors that need to be considered in the selection of revetment plants were summarized; and the types of ecological revetments commonly used in water conservancy projects were summarized and classified according to the proportion of natural materials in revetment materials through domestic and foreign research and engineering examples, and their applicable scope and relevant merits were introduced. In conclusion, ecological revetments should get rid of its own limitations in the practical application process, and the river regulation scheme and revetment type should be selected comprehensively and flexibly combined with the status quo.展开更多
Based on the analysis of construction project safety risk and its preventive measures, it is first necessary to clarify the safety risks and existing problems of construction project supervision and to formulate effec...Based on the analysis of construction project safety risk and its preventive measures, it is first necessary to clarify the safety risks and existing problems of construction project supervision and to formulate effective construction procedures. It is necessary to check the production safety of the construction unit, strengthen the company's own safety production management, and reasonably control the risk to familiarize with the construction drawings, and make a special construction plan for the work of the bottom line. Finally, an elective solution is drawn to comprehensively expound the importance of construction project construction safety risk and its preventive measures.展开更多
文摘Road and bridge engineering is an indispensable part of socialist economic construction in China, whose construction quality significantly affects the infrastructure construction level in the whole society. To meet the rapid economic development of various regions, construction scale and quantity of road and bridge engineering have been continuously expanded and increased, therefore, higher requirements for construction quality and construction standard are also presented. During the construction of road and bridge engineering, concrete crack is a key problem which affects the construction quality. In this regard, this paper analyzes cause and prevention measures of concrete cracks during the construction of road and bridge engineering, and hopes to provide construction personnel with valuable references.
文摘With the continuous development of economy and society, people's ability to transform society has been improved. To break the constraints of hydrological and climatic conditions, some hydrology and water conservancy projects were constructed to meet the needs of human activities. In the construction of hydrological engineering, geological conditions are first surveyed to determine whether there are significant geological structure problems, in order to enhance the stability of hydrological engineering and reduce the probability of hydrological engineering leakage.
文摘For engineering geological investigation, hydrographic surveys are particularly important. By operating the equipment, relevant technicians analyze hydrogeological data around the project. A series of corresponding measures were taken to ensure the smooth completion of the project. However, due to the inadequate completion of hydrogeological survey work, it has great harm to the later stage of engineering work, and even will lead to the final failure of the project. Based on this, this paper explores the hazards and prevention measures of hydrogeology in engineering surveys.
文摘With the rapid development of the social economy,people are paying more and more attention to environmental issues.If society wants sustainable development,it must put energy conservation and emission reduction on the agenda.At this stage,China has vigorously promoted energy conservation and emission reduction,and all walks of life have gradually embarked on the green road of energy conservation.In recent years,energy saving measures has been widely used in China's oilfield electrical engineering.The author explores and analyzes the basic principles of energy saving measures applied in oilfield electrical engineering,and proposes an effective way to apply energy saving measures in oilfield electrical engineering,hoping to contribute to the energy saving effect of oilfield electrical engineering.
文摘Building decoration engineering mainly carries out various decoration works for buildings,which can provide protection for building components,avoid the influence of nature as far as possible,and help to improve the function of buildings and prolong their life.At the same time,the building decoration project is an important part of the whole construction project,and the probability of bad situation is relatively large,so it is necessary to carry out in-depth exploration for the corresponding management work,clarify the existing problems,and put forward corresponding measures according to the actual situation.
文摘The air quality of the ecological enviro-nment is closely related to people's health.However,due to the rapid economic development in recent years,it has indirectly led to the continuous deterioration of the quality of the atmospheric environment.Effective control of air pollution in environmental engineering is an important measure to improve the ecological environment and the quality of people’s lives.Therefore,this paper combines the main causes and hazards of air pollution to analyze environmental protection measures in-depth.
文摘Deep foundation pit excavation is a basic and key step involved in modern building construction.In order to ensure the construction quality and safety of deep foundation pits,this paper takes a project as an example to analyze deep foundation pit excavation technology,including the nature of this construction project,the main technical measures in the construction of deep foundation pit,and the analysis of the safety risk prevention and control measures.The purpose of this analysis is to provide scientific reference for the construction quality and safety of deep foundation pits.
基金Project (50490272) supported by the National Natural Science Foundation of ChinaProject(040109) supported by the Doctor Degree Paper Innovation Engineering of Central South University
文摘The principle of sonic wave measurement was introduced, and cumulative damage effects of underground engineering rock mass under blasting load were studied by in situ test, using RSM-SY5 intelligent sonic wave apparatus. The blasting test was carried out for ten times at some tunnels of Changba Lead-Zinc Mine. The damage depth of surrounding rock caused by old blasting excavation (0.8-1.2 m) was confirmed. The relation between the cumulative damage degree and blast times was obtained. The results show that the sonic velocity decreases gradually with increasing blast times, hut the damage degree (D) increases. The damage cumulative law is non-linear. The damage degree caused by blast decreases with increasing distance, and damage effects become indistinct. The blasting damage of rock mass is anisotropic. The damage degree of rock mass within charging range is maximal. And the more the charge is, the more severe the damage degree of rock mass is. The test results provide references for researches of mechanical parameters of rock mass and dynamic stability analysis of underground chambers.
基金Project supported by the Science Foundation of Shanghai Munici pal Commission of Science and Technology ( Grant No.011461059)
文摘Acquisition of physical data with high precision is a key step in reverse engineering (RE). It is an important stimulative for the progress of reverse engineering with which various digitizing devices are invent ed, developed and made applicable. This paper introduces a three dimensional opt ical measurement method based on digital fringe projection technique in RE to im prove the technique through its application. A practical example is presented an d the result demonstrates the applicability and feasibility of the measurement s ystem as well as the reliability and validity of relevant methods and algorithms .
基金supported by the National Natural Science Foundation of China (Nos. 41501079 and 91647103)the self-determined Project Funded by State Key Laboratory of Frozen Soil Engineering (No. SKLFSE-ZQ-43)the Foundation for Excellent Youth Scholars of NIEER, CAS
文摘This article attempts to investigate the measure effect of rubble roadbed engineering in permafrost regions of Qinghai-Tibet Plateau. As a case study, Chaidaer-Muli Railway is used to evaluate the measure effect of rubble roadbed engineering in permafrost regions. The AHP(Analytic Hierarchy Process) method is thus employed to establish the evaluation indicator system. The evaluation factor is selected by analyzing the mutual relation between the permafrost environment and roadbed engineering. Thus, a hierarchical structure model is established based on the selected evaluation indices. Each factor is weighted to determine the status in the evaluation system, and grading standards are built for providing a basis for the evaluation. Then, the fuzzy mathematical method is introduced to evaluate the measure effect of rubble roadbed engineering in permafrost regions along the Chadaer-Muli Railway. Results show that most of the permafrost roadbed is in a preferable condition(b) along the Chaidaer-Muli Railway due to rubble engineering measures. This proportion reaches to 86.1%. The proportion in good(a), general(c) and poor states(d) are 0.0%, 7.5% and 6.4%, respectively, in all the evaluation sections along the Chaidaer-Muli Railway. Ground-temperature monitoring results are generally consistent with AHP-FUZZY evaluation results. This means that the AHP-FUZZY method can be applied to evaluate the effect of rubble roadbed engineering measures in permafrost regions. The effect evaluation of engineering measures will provide timely and effective feedback information for further engineering design. The series of engineering measures will more effectively protect permafrost stability.
文摘Data were collected from Three-north Region, Middle and upper reaches region of Yangtze River and Coastal region. By analysis of factors influencing soil erosion, the longitude, latitude, annual precipitation, and the slope degree were selected as regional independent variables and canopy density and stock litter were selected as independent variables, and integral diffusing models were established for evaluation of the benefit of soil and water conservation of forest. By solving the parameters of models using the package of STATISTICA, the Power function between independent variables and dependent variables was set up. The soil conservation amount of forest and economic values were estimated using the contrast method for the ecological forestry engineering of the above three areas.
文摘The intake swirl in the cylinder was induced by a swirler which was fixed in one of two intake ports. In order to understand the characteristics of the intake swirl, a transparent water analog was designed which simulated 150 type single cylinder engine. At the same time, the particle image velocimetry was used to measure the flow fields induced by various swirlers in the analog. After measurement, a new method was presented to evaluate the intensity of the intake swirl. Then, when the measured sections, the lifts of valve and the swirlers were different, the calculated results of the flow field were compared.
基金U nderthe auspicesofthe cooperative projectbetw een G overnm entofChina and Japan (N o.JIC A G L:SCH EFY 98)
文摘Chaohu Lake, located in the central Anhui Province, is one of the five largest fresh lakes in China. Now it is one of the three most eutrophication lakes in China. The deterioration of its water quality has influenced the sustainable development of society, economy and environment of Hefei City, the capital of Anhui Province. A series of measures have been carried out to control its eutrophication, but it is still serious. On the basis of the lake water quality data from 1984 to 2003, the causes of the eutrophication of Chaohu Lake are analyzed. Studies indicated that the suitable natural conditions and human activities played a crucial role in the process of the eutrophication of Chaohu Lake. A great amount of industrial, agricultural and domestic sewage discharged into the lake is the main cause of eutrophication in the lake. Land use, soil erosion and shoreline collapse destroyed the watershed eco-environment and the terrestrial ecosystem of Chaohu Lake. And the building of Yuxi Gate extends the sluggish of the nutritious substance and speeds up the process of the eutrophication. From the view of systematic engineering and watershed ecology, a series of the countermeasures have been put forward to control the eutrophication.
文摘Ground-motion Intensity Measures (IMs) are used to quantify the strength of ground motions and evaluate the response of structures. IMs act as a link between seismic demand and seismic hazard analysis and therefore, have a key role in performance-based earthquake engineering. Many studies have been carried out on the determination of suitable IMs in terms of effi ciency, suffi ciency and scaling robustness. The majority of these investigations focused on ordinary structures such as buildings and bridges, and only a few were about buried pipelines. In the current study, the optimal IMs for predicting the seismic demand of continuous buried steel pipelines under near-fi eld pulse-like ground motion records is investigated. Incremental dynamic analysis is performed using twenty ground motion records. Using the results of the regression analysis, the optimality of 23 potential IMs are studied. It is concluded that specifi c energy density (SED) followed by VSI[ω1(PGD+RMSd )] are the optimal IMs based on effi ciency, suffi ciency and scaling robustness for seismic response evaluation of buried pipelines under near-fi eld ground motions.
基金supported by ITER domestic research under specific task 2008GB107001
文摘ITER magnet gravity support (GS) has been redesigned as a structure of pre- assembled nmlti-flexible plates instead of the original welded structure. In the past several years, engineering tests of the new structure have been proposed. A prototype engineering test plat- form is being developed. In order to apply the loads/load combinations onto the test mock-up, seven hydraulic bolt tensioners in three directions have been applied to simulate various loads (forces and moments), through which the deformation of bolts, flexible plates and clamp blocks, the stress distribution in the flexible plates, the friction between the contact surface, etc. can be monitored/tested. The measurement and control system includes seven sets of synchronization controller, a 16-channel strain gauge, 25 sets of displacement sensors, etc. Principles of EDC220 digital controller and development of multi-channel control software are also demonstrated.
基金Project(IRT0950)supported by the Cheung Kong Scholars and the Development Plan of Innovative Team,ChinaProject supported by China Scholarship Council
文摘An improved multidirectional velocity model was proposed for more accurately locating micro-seismic events in rock engineering. It was assumed that the stress wave propagation velocities from a micro-seismic source to three nearest monitoring sensors in a sensor's array arrangement were the same. Since the defined objective function does not require pre-measurement of the stress wave propagation velocity in the field, errors from the velocity measurement can be avoided in comparison to three traditional velocity models. By analyzing 24 different cases, the proposed multidirectional velocity model iterated by the Simplex method is found to be the best option no matter the source is within the region of the sensor's array or not. The proposed model and the adopted iterative algorithm are verified by field data and it is concluded that it can significantly reduce the error of the estimated source location.
文摘Under the premise of building an innovation-oriented country and cultivating new engineering innovative talents, how to carry out the teaching of professional innovative learning, cultivate the innovative thinking of the students, and improve the teaching mode and the curriculum form have become the main directions for deepening the reform of higher education. This article analyses the main problems existing in cultivating new engineering innovative talents for college students, probes into solutions, puts forward teaching methods and gives evaluation methods. The use of CDIO, innovative practice, combining production, learning and research methods to improve students' innovative abilities, practice shows that the exploration of reform can get a good training effect.
文摘Compared with traditional bank protection, ecological revetments, as a new type of bank protection, can ensure the sustainable and healthy development of river ecology and has broad application prospects. In this paper, the design principles for ecological revetments and the factors that need to be considered in the selection of revetment plants were summarized; and the types of ecological revetments commonly used in water conservancy projects were summarized and classified according to the proportion of natural materials in revetment materials through domestic and foreign research and engineering examples, and their applicable scope and relevant merits were introduced. In conclusion, ecological revetments should get rid of its own limitations in the practical application process, and the river regulation scheme and revetment type should be selected comprehensively and flexibly combined with the status quo.
文摘Based on the analysis of construction project safety risk and its preventive measures, it is first necessary to clarify the safety risks and existing problems of construction project supervision and to formulate effective construction procedures. It is necessary to check the production safety of the construction unit, strengthen the company's own safety production management, and reasonably control the risk to familiarize with the construction drawings, and make a special construction plan for the work of the bottom line. Finally, an elective solution is drawn to comprehensively expound the importance of construction project construction safety risk and its preventive measures.