This paper presents a method of forecasting stable operation of gas compressor unit (GCU) centrifugal supercharger (CFS) installed on a piping of compressor shops servicing gas pipelines. The stability of supercharger...This paper presents a method of forecasting stable operation of gas compressor unit (GCU) centrifugal supercharger (CFS) installed on a piping of compressor shops servicing gas pipelines. The stability of superchargers operation is assessed in relation to the phenomenon of surge. Solution of this problem amounts to the development and numerical analysis of a set of ordinary differential equations. The set describes transmission of gas through a compressor shop as a fluid dynamics model with lumped parameters. The proposed method is oriented to wide application by specialists working in the gas industry. The practical application of this method can use all-purpose programming and mathematical software available to specialists of gas companies.展开更多
One of the roles of nuctear regulators is to review population projections calculated by applicants for populations lying in the vicinity of nuclear power plants. This paper examines methods of calculating rates of gr...One of the roles of nuctear regulators is to review population projections calculated by applicants for populations lying in the vicinity of nuclear power plants. This paper examines methods of calculating rates of growth and thus calculating future population growth. This paper is concerned about regulators making sure that nuclear power plants are not located near densely populated centers and that population centers located near nuclear power plants do not become densely populated. In the case of El Dabaa city in the north coast of Egypt, south west of the nominated plant site, three rates of growth 1.5%, 2.5% and 3% were identified. The first is the current population growth rate of the city, the second is the average national growth rate and the third is the expected growth rate of the city when the nuclear power plant gets constructed and operated. In all three cases, this city is a population center and rules of distance from the nuclear power plant shall apply. Thus the further natural growth of this city should be controlled and directed away from the downwind of the plant.展开更多
Using the measured data to analyze the change rule of water increase and decrease in the coastal waters of Tanggu station.The water increase caused by the temperate cyclone in winter accounts for a higher frequency in...Using the measured data to analyze the change rule of water increase and decrease in the coastal waters of Tanggu station.The water increase caused by the temperate cyclone in winter accounts for a higher frequency in the whole year,and the water increase caused by the tropical cyclone in summer is larger,which brings serious storm surge disasters.This paper determines the maximum tropical cyclone parameters through statistics of historical typhoon processes,establishes a numerical model of storm water increase and decrease,and calculates the maximum possible water increase caused by typhoons in this sea area,and the water increase value is 3.6 m.A gale sensitivity experiment was constructed,and the maximum possible increase or decrease of water in the gale was calculated.展开更多
Visual inspection of the key components of nuclear power plants(NPPs)is important for NPP operation and maintenance. However,the underwater environment and existing radiation will lead to image degradation,thus making...Visual inspection of the key components of nuclear power plants(NPPs)is important for NPP operation and maintenance. However,the underwater environment and existing radiation will lead to image degradation,thus making it difficult to identify surface defects. In this study,a method for improving the quality of underwater images is proposed.By analyzing the degradation characteristics of underwater detection image,the image enhancement technology is used to improve the color richness of the image,and then the improved dark channel prior(DCP)algorithm is used to restore it. By modifying the estimation formula of transmittance and background light,the correction of insufficient brightness in DCP restored image is realized. The proposed method is compared with other state-of-the-art methods. The results show that the proposed method can achieve higher scores and improve the image quality by correcting the color and restoring local details,thus effectively enhancing the reliability of visual inspection of NPPs.展开更多
文摘This paper presents a method of forecasting stable operation of gas compressor unit (GCU) centrifugal supercharger (CFS) installed on a piping of compressor shops servicing gas pipelines. The stability of superchargers operation is assessed in relation to the phenomenon of surge. Solution of this problem amounts to the development and numerical analysis of a set of ordinary differential equations. The set describes transmission of gas through a compressor shop as a fluid dynamics model with lumped parameters. The proposed method is oriented to wide application by specialists working in the gas industry. The practical application of this method can use all-purpose programming and mathematical software available to specialists of gas companies.
文摘One of the roles of nuctear regulators is to review population projections calculated by applicants for populations lying in the vicinity of nuclear power plants. This paper examines methods of calculating rates of growth and thus calculating future population growth. This paper is concerned about regulators making sure that nuclear power plants are not located near densely populated centers and that population centers located near nuclear power plants do not become densely populated. In the case of El Dabaa city in the north coast of Egypt, south west of the nominated plant site, three rates of growth 1.5%, 2.5% and 3% were identified. The first is the current population growth rate of the city, the second is the average national growth rate and the third is the expected growth rate of the city when the nuclear power plant gets constructed and operated. In all three cases, this city is a population center and rules of distance from the nuclear power plant shall apply. Thus the further natural growth of this city should be controlled and directed away from the downwind of the plant.
文摘Using the measured data to analyze the change rule of water increase and decrease in the coastal waters of Tanggu station.The water increase caused by the temperate cyclone in winter accounts for a higher frequency in the whole year,and the water increase caused by the tropical cyclone in summer is larger,which brings serious storm surge disasters.This paper determines the maximum tropical cyclone parameters through statistics of historical typhoon processes,establishes a numerical model of storm water increase and decrease,and calculates the maximum possible water increase caused by typhoons in this sea area,and the water increase value is 3.6 m.A gale sensitivity experiment was constructed,and the maximum possible increase or decrease of water in the gale was calculated.
基金supported by the National Natural Science Foundations of China (Nos. 51674031,51874022)。
文摘Visual inspection of the key components of nuclear power plants(NPPs)is important for NPP operation and maintenance. However,the underwater environment and existing radiation will lead to image degradation,thus making it difficult to identify surface defects. In this study,a method for improving the quality of underwater images is proposed.By analyzing the degradation characteristics of underwater detection image,the image enhancement technology is used to improve the color richness of the image,and then the improved dark channel prior(DCP)algorithm is used to restore it. By modifying the estimation formula of transmittance and background light,the correction of insufficient brightness in DCP restored image is realized. The proposed method is compared with other state-of-the-art methods. The results show that the proposed method can achieve higher scores and improve the image quality by correcting the color and restoring local details,thus effectively enhancing the reliability of visual inspection of NPPs.