Benefit evaluation of debris flow prevention and control projects was one of the essential contents of debris flow prevention and mitigation work.In order to scientifically and quantitatively evaluate the comprehensiv...Benefit evaluation of debris flow prevention and control projects was one of the essential contents of debris flow prevention and mitigation work.In order to scientifically and quantitatively evaluate the comprehensive benefit of debris flow prevention and control projects,this study identified nine factors as evaluation indicators from economic,social,and ecological aspects.The projection pursuit(PP) model based on the improved particle swarm optimization(IPSO) algorithm was used to construct a mathematical model to evaluate the benefit of debris flow prevention and control projects.The interpolation method was applied to divide the benefit grades.The debris flow prevention and control projects in Qipan,Taoguan,Chutou,Anjia,and Mozi gullies in Wenchuan County were chosen as typical cases for empirical analysis.The case study revealed that,among the criteria layer indicators,investment per unit of the protected area,investment per unit of the protected population,the amount of water and soil conservation,and reduction rate of accumulation fan had the most significant weights.The social and ecological benefits were found to be the more important in the target layer.The comprehensive benefit of Qipan,Taoguan,Chutou,Anjia,and Mozi gullies was found to be 4.44,4.83,1.95,3,and 2,respectively.The benefit ranking of the five gullies was consistent with their effectiveness in disaster prevention ranking in the flood season of 2019.Therefore,it could prove that the newly-built benefit evaluation model was practical and feasible,and the evaluation results of the sample could be reasonably interpreted,which verified the effectiveness of the methods.展开更多
Suzhou City,located in the Yangtze River Delta in China,is prone to flooding due to a complex combination of natural factors,including its monsoon climate,low elevation,and tidally influenced position,as well as inten...Suzhou City,located in the Yangtze River Delta in China,is prone to flooding due to a complex combination of natural factors,including its monsoon climate,low elevation,and tidally influenced position,as well as intensive human activities.The Large Encirclement Flood Control Project(LEFCP)was launched to cope with serious floods in the urban area.This project changed the spatiotemporal pattern of flood processes and caused spatial diversion of floods from the urban area to the outskirts of the city.Therefore,this study developed a distributed flood simulation model in order to understand this transition of flood processes.The results revealed that the LEFCP effectively protected the urban areas from floods,but the present scheduling schemes resulted in the spatial diversion of floods to the outskirts of the city.With rainstorm frequencies of 10.0%to 0.5%,the water level differences between two representative water level stations(Miduqiao(MDQ)and Fengqiao(FQ))located inside and outside the LEFCP area,ranged from 0.75 m to 0.24 m and from 1.80 m to 1.58 m,respectively.In addition,the flood safety margin at MDQ and the duration with the water level exceeding the warning water level at FQ ranged from 0.95 m to 0.43 m and from 4 h to 22 h,respectively.Rational scheduling schemes for the hydraulic facilities of the LEFCP in extreme precipitation cases were developed ac-cording to food simulations under seven scheduling scenarios.This helps to regulate the spatial flood diversion caused by the LEFCP during extreme precipitation.展开更多
Launched in 2002, the Beiing–Tianjin Sand Source Control Project (BTSSCP) is an ecological restoration project intended to prevent desertification in China. Evidence from multiple sources has confirmed increases in v...Launched in 2002, the Beiing–Tianjin Sand Source Control Project (BTSSCP) is an ecological restoration project intended to prevent desertification in China. Evidence from multiple sources has confirmed increases in vegetation growth in the BTSSCP region since the initiation of this project. Precipitation and essential climate variable-soil moisture (ECV-SM) conditions are typically considered to be the main drivers of vegetation growth in this region. Although many studies have investigated the inter-annual variations of vegetation growth, few concerns have been focused on the annual and seasonal variations of vegetation growth and their climatic drivers, which are crucial for understanding the relationships among the climate, vegetation, and human activities at the regional scale. Based on the normalized difference vegetation index (NDVI) derived from MODIS and the corresponding climatic data, we explored the responses of vegetation growth to climatic factors at annual and seasonal scales in the BTSSCP region during the period 2000–2014. Over the study region as a whole, NDVI generally increased from 2000 to 2014, at a rate of 0.002/a. Vegetation growth is stimulated mainly by the elevated temperature in spring, whereas precipitation is the leading driver of summer greening. In autumn, positive effects of both temperature and precipitation on vegetation growth were observed. The warming in spring promotes vegetation growth but reduces ECV-SM. Summer greening has a strong cooling effect on land surface temperature. These results indicate that the ecological and environmental consequences of ecological restoration projects should be comprehensively evaluated.展开更多
Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the eff...Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events.展开更多
The article simply describes the difficulties of the Mould and Die project control,and then put forward the thoughts of developing the Monitoring and Early Warning System for the Mould and Die manufacturing.Afterwards...The article simply describes the difficulties of the Mould and Die project control,and then put forward the thoughts of developing the Monitoring and Early Warning System for the Mould and Die manufacturing.Afterwards,the main three constructing principles and the goals of the system are explained carefully.Based on those,the theory and the classifications of the Monitoring and Early Warning are expounded.With the assistance of the use case diagram of UML(the United Modeling Language),the main functions of the system are analyzed;and with the activity diagram of the UML,the work flows of the monitoring and early warning are expressed clearly.Finally,the classes and the architectures of the system are designed by making use of the class diagram of UML.展开更多
According to the strategic goal of sustainable development,construction and management for the construction of Shendong mining area with ecological safety,the ecological restoration principle of ＂ control protects de...According to the strategic goal of sustainable development,construction and management for the construction of Shendong mining area with ecological safety,the ecological restoration principle of ＂ control protects development and development promotes control＂ for desertification prevention and control was adopted,and engineering measures,plant greening measures,and enclosure management and protection measures were taken to prevent and control desertification in the mining area based on careful detailed investigation and accurate planning and design in the early period. After 32 years,the desertification ecological landscape environment of the mining area has undergone a qualitative change,and the vegetation coverage has increased from 3%-8% to above 60% after the development. The former desertification land has become a modern green energy base that has produced 200 million tons of coal every year. The construction and management mode of an ecologically safe and modernized green coal mining area built by Shendong in the desertification region of northwestern China shows that taking appropriate comprehensive ecological restoration construction technology and management measures that integrate engineering,plants and enclosure management and protection is an effective technical and management paradigm for the construction of a modernized green large-scale coal mining area in China＇s arid and semi-arid regions.展开更多
In the management of engineering projects, cost control must be effectively implemented and it should be implemented in the whole process of project management. Of course, the cost control of engineering projects pres...In the management of engineering projects, cost control must be effectively implemented and it should be implemented in the whole process of project management. Of course, the cost control of engineering projects presents a strong technical, professional, which requires engineering consulting units to sum up the work experience, so as to ensure that the project cost control is more effective. Therefore, the whole process cost control of the project is mainly discussed in order to realize the fairness and fairness of the cost and to ensure the benefit of the project investment.展开更多
In the process of construction and operation, large volume concrete structures often generate large temperature stress, which in turn leads to cracks. Before the construction of concrete structures, in order to select...In the process of construction and operation, large volume concrete structures often generate large temperature stress, which in turn leads to cracks. Before the construction of concrete structures, in order to select timely and reasonable temperature control and crack prevention measures, this paper takes the upper lock head of the Datengxia Water Control Project as an example, and uses three-dimensional finite element method to simulate and recheck and calculate the temperature field and creep stress field according to the construction progress, latest material parameters and accurate boundary conditions. The analysis results show that the overall stress of the concrete at the upper gate head is not large after the temperature control measures formulated in this paper are adopted, which meets the requirements of concrete crack prevention, indicating that the temperature control measures formulated are appropriate.展开更多
The risk prevention and control in construction projects heavily relies on the systematic optimization of on-site safety management measures.Studies show that technical means such as safety education and training,dyna...The risk prevention and control in construction projects heavily relies on the systematic optimization of on-site safety management measures.Studies show that technical means such as safety education and training,dynamic monitoring of hazard sources directly reduce the probability of accidents.The full-staff responsibility system and performance evaluation indirectly enhance the resilience of risk prevention and control by shaping a culture of risk awareness.Based on the new local safety officer qualification regulations and the mandatory promotion of digital tools by 2025,case analysis indicates that the collaborative application of BIM and AI early warning platforms can reduce the risk of falls from height by 45%.The rigid constraints of systems,technological innovation and iteration,and the cultivation of cultural ecosystems form a multi-dimensional collaborative mechanism.In the future,it is necessary to integrate intelligent perception with green construction standards to achieve an upgrade in risk management efficiency.展开更多
Earned duration management(EDM)is a methodology for project schedule management(PSM)that can be considered an alternative to earned value management(EVM).EDM provides an estimation of devia-tions in schedule and a fin...Earned duration management(EDM)is a methodology for project schedule management(PSM)that can be considered an alternative to earned value management(EVM).EDM provides an estimation of devia-tions in schedule and a final project duration estimation.There is a key difference between EDM and EVM:In EDM,the value of activities is expressed as work periods;whereas in EVM,value is expressed in terms of cost.In this paper,we present how EDM can be applied to monitor and control stochastic pro-jects.To explain the methodology,we use a real case study with a project that presents a high level of uncertainty and activities with random durations.We analyze the usability of this approach according to the activities network topology and compare the EVM and earned schedule methodology(ESM)for PSM.展开更多
For the evaluation of construction quality and the verification of the design of water conservancy and hydropower engineering projects, and especially for the control of dam safety operation behavior, safety monitorin...For the evaluation of construction quality and the verification of the design of water conservancy and hydropower engineering projects, and especially for the control of dam safety operation behavior, safety monitoring sensors are employed in a majority of engineering projects. These sensors are used to monitor the project during the dam construction and operation periods, and play an important role in reservoir safety operation and producing benefits. With the changing of operating environments and run-time of projects, there are some factors affecting the operation and management of projects, such as a certain amount of damaged sensors and instability of the measured data. Therefore, it is urgent to evaluate existing safety monitoring sensors in water conservancy and hydropower engineering projects. However, there are neither standards nor evaluation guidelines at present. Based on engineering practice, this study examined some key techniques for the evaluation of safety monitoring sensors, including the evaluation process of the safety monitoring system, on-site detection methods of two typical pieces of equipment, the differential resistor sensor and vibrating wire sensor, the on-site detection methods of communication cable faults, and a validity test of the sensor measured data. These key techniques were applied in the Xiaolangdi Water Control Project and Xiaoxi Hydropower Project. The results show that the measured data of a majority of sensors are reliable and reasonable, and can reasonably reflect the structural change behavior in the project operating process, indicating that the availabilities of the safety monitoring sensors of the two projects are high展开更多
The progress of the World Bank loaned TB control project implemented from the second quarter of 1991 to the fourth quarter of 1993 was reported in this paper. In the past three years, 737 counties of the 12 provinces ...The progress of the World Bank loaned TB control project implemented from the second quarter of 1991 to the fourth quarter of 1993 was reported in this paper. In the past three years, 737 counties of the 12 provinces with the popula-展开更多
Karst areas in southwest China have experienced significant land cover and land use change(LUCC)due to utilization for human activity and a comprehensive rocky desertification control project(RDCP)since 2008.It is imp...Karst areas in southwest China have experienced significant land cover and land use change(LUCC)due to utilization for human activity and a comprehensive rocky desertification control project(RDCP)since 2008.It is important to quantify the effect of LUCC on ecosystem productivity in this region for assessing the overall benefit of this ecological restoration project.In this study,we used using MODIS land cover and NPP products to investigate the relative contribution of LUCC to the change in net primary productivity(NPP)during 2008–2013 in Huanjiang County,one of first one hundred pilot counties to implement RDCP.Our results show that NPP increased in 95.53%of the county,and the average growth of NPP in non-rocky desertification area was higher than in rocky desertification or potential rocky desertification areas.LUCC has an important contribution(25.23%)to the NPP increase in the county,especially in the LUCC area(70.97%),which increased the average NPP by 3.9%and 10.5%,respectively.Across the six RDCP regions in the county,the average increase in NPP for the vegetation restoration measure of governed karst area is significantly greater than in the ungoverned karst area,and the positive change in NPP increased with the increasing implementation area of the vegetation restoration measure.展开更多
The ability to accurately characterize projects novel project characteristic is developed characteristic, called project regularity, is essential to good project management. Therefore, a reflects the value accrue with...The ability to accurately characterize projects novel project characteristic is developed characteristic, called project regularity, is essential to good project management. Therefore, a reflects the value accrue within a project. This expressed in terms of the newly introduced regular/irregular-indicator RI. The widely accepted management system of earned value management （EVM） forms the basis for evaluation of the new characteristic. More concretely, the influence of project regularity on EVMforecasting accuracy is assessed, and is shown to be significant for both time and cost forecasting. Moreover, this effect appears to be stronger than that of the widely used characteristic of project seriality expressed by the serial/parallel-indicator SP. Therefore, project regularity could also be useful as an input parameter for project network generators. Furthermore, the introduction of project regularity can provide project managers with a more accurate indication of the time and cost forecasting accuracy that is to be expected for a certain project and, correspondingly, of how a project should be built up in order to obtain more reliable forecasts during project control.展开更多
Modern international project management has entered the phase of precise and accurate project management after the global financial crisis broke out at the beginning of the 21 stcentury. However, its development has f...Modern international project management has entered the phase of precise and accurate project management after the global financial crisis broke out at the beginning of the 21 stcentury. However, its development has faced new challenges since there has been lack of explicitly unanimous definition for the capability dimensions of precise and accurate project management, as well as the models and their process control parameters. The required core capabilities based on the precise and accurate project management for various rings are involved in the project life cycle, namely, the required internationally core competences and their components for the phases of project strategic planning and decision making in the early project phase, as well as the value engineering, and the project supervision and controls during the execution phase.Through studying the effects of the internationally core competences based on precise and accurate project management capabilities for the success and excellence of projects and configuring such models, the goal is to help the main contractors continuously obtain project success and excellence, thus improve its internationally core competences with continuous project success and excellence.展开更多
After having completed river regulation work in recent years, the dike distance up the reach of Lutaizi has been extended to 1.5 2.0 km in the Huaihe river. When the middle flood happened,such as those in 1956, 1982 ...After having completed river regulation work in recent years, the dike distance up the reach of Lutaizi has been extended to 1.5 2.0 km in the Huaihe river. When the middle flood happened,such as those in 1956, 1982 and 1991, flood can pass through safely. If the flood of 1% frequency happens, the flood discharge at Lutaizi will be larger than safe flood discharge 10000 m 3/s in downstream Lutaizi. By storing flood with the Linhuaigang sluice, the discharge of Lutaizi will not be over 10000 m 3/s. Cities in downstream Lutaizi will be free from flood.展开更多
基金financially supported by the National Key Research and Development Program(No.2018YFC1505402)the National Natural Science Foundation of China(No.41871174)+1 种基金the Science and Technology Department of Sichuan Province(No.2020YFSY0013)the Fundamental Research Funds for the Central Universities Project(No.2682019CX19)。
文摘Benefit evaluation of debris flow prevention and control projects was one of the essential contents of debris flow prevention and mitigation work.In order to scientifically and quantitatively evaluate the comprehensive benefit of debris flow prevention and control projects,this study identified nine factors as evaluation indicators from economic,social,and ecological aspects.The projection pursuit(PP) model based on the improved particle swarm optimization(IPSO) algorithm was used to construct a mathematical model to evaluate the benefit of debris flow prevention and control projects.The interpolation method was applied to divide the benefit grades.The debris flow prevention and control projects in Qipan,Taoguan,Chutou,Anjia,and Mozi gullies in Wenchuan County were chosen as typical cases for empirical analysis.The case study revealed that,among the criteria layer indicators,investment per unit of the protected area,investment per unit of the protected population,the amount of water and soil conservation,and reduction rate of accumulation fan had the most significant weights.The social and ecological benefits were found to be the more important in the target layer.The comprehensive benefit of Qipan,Taoguan,Chutou,Anjia,and Mozi gullies was found to be 4.44,4.83,1.95,3,and 2,respectively.The benefit ranking of the five gullies was consistent with their effectiveness in disaster prevention ranking in the flood season of 2019.Therefore,it could prove that the newly-built benefit evaluation model was practical and feasible,and the evaluation results of the sample could be reasonably interpreted,which verified the effectiveness of the methods.
基金supported by the National Natural Science Foundation of China(Grants No.42001025 and 42001014)the Belt and Road Special Foundation of the State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering(Grant No.2021491211)the Natural Science Foundation of Ningbo Municipality(Grant No.2023J133).
文摘Suzhou City,located in the Yangtze River Delta in China,is prone to flooding due to a complex combination of natural factors,including its monsoon climate,low elevation,and tidally influenced position,as well as intensive human activities.The Large Encirclement Flood Control Project(LEFCP)was launched to cope with serious floods in the urban area.This project changed the spatiotemporal pattern of flood processes and caused spatial diversion of floods from the urban area to the outskirts of the city.Therefore,this study developed a distributed flood simulation model in order to understand this transition of flood processes.The results revealed that the LEFCP effectively protected the urban areas from floods,but the present scheduling schemes resulted in the spatial diversion of floods to the outskirts of the city.With rainstorm frequencies of 10.0%to 0.5%,the water level differences between two representative water level stations(Miduqiao(MDQ)and Fengqiao(FQ))located inside and outside the LEFCP area,ranged from 0.75 m to 0.24 m and from 1.80 m to 1.58 m,respectively.In addition,the flood safety margin at MDQ and the duration with the water level exceeding the warning water level at FQ ranged from 0.95 m to 0.43 m and from 4 h to 22 h,respectively.Rational scheduling schemes for the hydraulic facilities of the LEFCP in extreme precipitation cases were developed ac-cording to food simulations under seven scheduling scenarios.This helps to regulate the spatial flood diversion caused by the LEFCP during extreme precipitation.
基金financially supported by the National Natural Science Foundation of China (31560135, 41361100)the Discipline Construction Fund Project of Gansu Agricultural University (GAU-XKJS-2018-104, GAU-XKJS-2018-108)the Gansu Science and Technology Support Program (1604FKCA088)
文摘Launched in 2002, the Beiing–Tianjin Sand Source Control Project (BTSSCP) is an ecological restoration project intended to prevent desertification in China. Evidence from multiple sources has confirmed increases in vegetation growth in the BTSSCP region since the initiation of this project. Precipitation and essential climate variable-soil moisture (ECV-SM) conditions are typically considered to be the main drivers of vegetation growth in this region. Although many studies have investigated the inter-annual variations of vegetation growth, few concerns have been focused on the annual and seasonal variations of vegetation growth and their climatic drivers, which are crucial for understanding the relationships among the climate, vegetation, and human activities at the regional scale. Based on the normalized difference vegetation index (NDVI) derived from MODIS and the corresponding climatic data, we explored the responses of vegetation growth to climatic factors at annual and seasonal scales in the BTSSCP region during the period 2000–2014. Over the study region as a whole, NDVI generally increased from 2000 to 2014, at a rate of 0.002/a. Vegetation growth is stimulated mainly by the elevated temperature in spring, whereas precipitation is the leading driver of summer greening. In autumn, positive effects of both temperature and precipitation on vegetation growth were observed. The warming in spring promotes vegetation growth but reduces ECV-SM. Summer greening has a strong cooling effect on land surface temperature. These results indicate that the ecological and environmental consequences of ecological restoration projects should be comprehensively evaluated.
基金supported by the project of the China Geological Survey(No.DD20221746)the National Natural Science Foundation of China(Grant Nos.41101086)。
文摘Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events.
文摘The article simply describes the difficulties of the Mould and Die project control,and then put forward the thoughts of developing the Monitoring and Early Warning System for the Mould and Die manufacturing.Afterwards,the main three constructing principles and the goals of the system are explained carefully.Based on those,the theory and the classifications of the Monitoring and Early Warning are expounded.With the assistance of the use case diagram of UML(the United Modeling Language),the main functions of the system are analyzed;and with the activity diagram of the UML,the work flows of the monitoring and early warning are expressed clearly.Finally,the classes and the architectures of the system are designed by making use of the class diagram of UML.
文摘According to the strategic goal of sustainable development,construction and management for the construction of Shendong mining area with ecological safety,the ecological restoration principle of ＂ control protects development and development promotes control＂ for desertification prevention and control was adopted,and engineering measures,plant greening measures,and enclosure management and protection measures were taken to prevent and control desertification in the mining area based on careful detailed investigation and accurate planning and design in the early period. After 32 years,the desertification ecological landscape environment of the mining area has undergone a qualitative change,and the vegetation coverage has increased from 3%-8% to above 60% after the development. The former desertification land has become a modern green energy base that has produced 200 million tons of coal every year. The construction and management mode of an ecologically safe and modernized green coal mining area built by Shendong in the desertification region of northwestern China shows that taking appropriate comprehensive ecological restoration construction technology and management measures that integrate engineering,plants and enclosure management and protection is an effective technical and management paradigm for the construction of a modernized green large-scale coal mining area in China＇s arid and semi-arid regions.
文摘In the management of engineering projects, cost control must be effectively implemented and it should be implemented in the whole process of project management. Of course, the cost control of engineering projects presents a strong technical, professional, which requires engineering consulting units to sum up the work experience, so as to ensure that the project cost control is more effective. Therefore, the whole process cost control of the project is mainly discussed in order to realize the fairness and fairness of the cost and to ensure the benefit of the project investment.
文摘In the process of construction and operation, large volume concrete structures often generate large temperature stress, which in turn leads to cracks. Before the construction of concrete structures, in order to select timely and reasonable temperature control and crack prevention measures, this paper takes the upper lock head of the Datengxia Water Control Project as an example, and uses three-dimensional finite element method to simulate and recheck and calculate the temperature field and creep stress field according to the construction progress, latest material parameters and accurate boundary conditions. The analysis results show that the overall stress of the concrete at the upper gate head is not large after the temperature control measures formulated in this paper are adopted, which meets the requirements of concrete crack prevention, indicating that the temperature control measures formulated are appropriate.
文摘The risk prevention and control in construction projects heavily relies on the systematic optimization of on-site safety management measures.Studies show that technical means such as safety education and training,dynamic monitoring of hazard sources directly reduce the probability of accidents.The full-staff responsibility system and performance evaluation indirectly enhance the resilience of risk prevention and control by shaping a culture of risk awareness.Based on the new local safety officer qualification regulations and the mandatory promotion of digital tools by 2025,case analysis indicates that the collaborative application of BIM and AI early warning platforms can reduce the risk of falls from height by 45%.The rigid constraints of systems,technological innovation and iteration,and the cultivation of cultural ecosystems form a multi-dimensional collaborative mechanism.In the future,it is necessary to integrate intelligent perception with green construction standards to achieve an upgrade in risk management efficiency.
基金financed by the Regional Government of Castille and Leon(Spain)with Grant(VA180P20).
文摘Earned duration management(EDM)is a methodology for project schedule management(PSM)that can be considered an alternative to earned value management(EVM).EDM provides an estimation of devia-tions in schedule and a final project duration estimation.There is a key difference between EDM and EVM:In EDM,the value of activities is expressed as work periods;whereas in EVM,value is expressed in terms of cost.In this paper,we present how EDM can be applied to monitor and control stochastic pro-jects.To explain the methodology,we use a real case study with a project that presents a high level of uncertainty and activities with random durations.We analyze the usability of this approach according to the activities network topology and compare the EVM and earned schedule methodology(ESM)for PSM.
基金supported by the National Natural Science Foundation of China(Grants No.51179108and50909066)the Key Research Foundation of Nanjing Hydraulic Research Institute(Grant No.Y711007)
文摘For the evaluation of construction quality and the verification of the design of water conservancy and hydropower engineering projects, and especially for the control of dam safety operation behavior, safety monitoring sensors are employed in a majority of engineering projects. These sensors are used to monitor the project during the dam construction and operation periods, and play an important role in reservoir safety operation and producing benefits. With the changing of operating environments and run-time of projects, there are some factors affecting the operation and management of projects, such as a certain amount of damaged sensors and instability of the measured data. Therefore, it is urgent to evaluate existing safety monitoring sensors in water conservancy and hydropower engineering projects. However, there are neither standards nor evaluation guidelines at present. Based on engineering practice, this study examined some key techniques for the evaluation of safety monitoring sensors, including the evaluation process of the safety monitoring system, on-site detection methods of two typical pieces of equipment, the differential resistor sensor and vibrating wire sensor, the on-site detection methods of communication cable faults, and a validity test of the sensor measured data. These key techniques were applied in the Xiaolangdi Water Control Project and Xiaoxi Hydropower Project. The results show that the measured data of a majority of sensors are reliable and reasonable, and can reasonably reflect the structural change behavior in the project operating process, indicating that the availabilities of the safety monitoring sensors of the two projects are high
文摘The progress of the World Bank loaned TB control project implemented from the second quarter of 1991 to the fourth quarter of 1993 was reported in this paper. In the past three years, 737 counties of the 12 provinces with the popula-
基金The National Key Research&Development Program of China(2016YFC0500204)The National Natural Science Foundation of China(41571130043,31420103917,31971512)。
文摘Karst areas in southwest China have experienced significant land cover and land use change(LUCC)due to utilization for human activity and a comprehensive rocky desertification control project(RDCP)since 2008.It is important to quantify the effect of LUCC on ecosystem productivity in this region for assessing the overall benefit of this ecological restoration project.In this study,we used using MODIS land cover and NPP products to investigate the relative contribution of LUCC to the change in net primary productivity(NPP)during 2008–2013 in Huanjiang County,one of first one hundred pilot counties to implement RDCP.Our results show that NPP increased in 95.53%of the county,and the average growth of NPP in non-rocky desertification area was higher than in rocky desertification or potential rocky desertification areas.LUCC has an important contribution(25.23%)to the NPP increase in the county,especially in the LUCC area(70.97%),which increased the average NPP by 3.9%and 10.5%,respectively.Across the six RDCP regions in the county,the average increase in NPP for the vegetation restoration measure of governed karst area is significantly greater than in the ungoverned karst area,and the positive change in NPP increased with the increasing implementation area of the vegetation restoration measure.
文摘The ability to accurately characterize projects novel project characteristic is developed characteristic, called project regularity, is essential to good project management. Therefore, a reflects the value accrue within a project. This expressed in terms of the newly introduced regular/irregular-indicator RI. The widely accepted management system of earned value management （EVM） forms the basis for evaluation of the new characteristic. More concretely, the influence of project regularity on EVMforecasting accuracy is assessed, and is shown to be significant for both time and cost forecasting. Moreover, this effect appears to be stronger than that of the widely used characteristic of project seriality expressed by the serial/parallel-indicator SP. Therefore, project regularity could also be useful as an input parameter for project network generators. Furthermore, the introduction of project regularity can provide project managers with a more accurate indication of the time and cost forecasting accuracy that is to be expected for a certain project and, correspondingly, of how a project should be built up in order to obtain more reliable forecasts during project control.
文摘Modern international project management has entered the phase of precise and accurate project management after the global financial crisis broke out at the beginning of the 21 stcentury. However, its development has faced new challenges since there has been lack of explicitly unanimous definition for the capability dimensions of precise and accurate project management, as well as the models and their process control parameters. The required core capabilities based on the precise and accurate project management for various rings are involved in the project life cycle, namely, the required internationally core competences and their components for the phases of project strategic planning and decision making in the early project phase, as well as the value engineering, and the project supervision and controls during the execution phase.Through studying the effects of the internationally core competences based on precise and accurate project management capabilities for the success and excellence of projects and configuring such models, the goal is to help the main contractors continuously obtain project success and excellence, thus improve its internationally core competences with continuous project success and excellence.
文摘After having completed river regulation work in recent years, the dike distance up the reach of Lutaizi has been extended to 1.5 2.0 km in the Huaihe river. When the middle flood happened,such as those in 1956, 1982 and 1991, flood can pass through safely. If the flood of 1% frequency happens, the flood discharge at Lutaizi will be larger than safe flood discharge 10000 m 3/s in downstream Lutaizi. By storing flood with the Linhuaigang sluice, the discharge of Lutaizi will not be over 10000 m 3/s. Cities in downstream Lutaizi will be free from flood.
