Climate change is accelerating globally,raising significant concerns regarding the environmental risks associated with combined sewer overflows(CSOs).These rainfall events lead to the excessive discharge of multiple p...Climate change is accelerating globally,raising significant concerns regarding the environmental risks associated with combined sewer overflows(CSOs).These rainfall events lead to the excessive discharge of multiple pollutants into natural waters.However,greenhouse gas(GHG)emissions from CSOs,which are crucial for carbon neutrality in urban water systems,remain fragmented.Using the life-cycle assess-ment method expansion approach,this study breaks down the formation and discharge processes of CSOs and uncovers the underlying mechanisms driving GHG emissions during each period.Given the complex-ity and uncertainty in the spatial distribution of GHG emissions from CSOs,the development of standard monitoring and estimation methods is vital.This study identifies the factors influencing GHG emissions within the urban drainage system(UDS)and defines the interactive GHG emission boundaries and accounting framework related to CSOs.This framework is expanded to consider the hybrid nature of urban engineering and hydraulic interactions during the CSO events.Advanced modeling technologies have emerged as essential tools for predicting and managing GHG emissions from CSOs.This review pro-motes comprehensive data-driven methods for predicting GHG emissions from CSOs,fully considering the inherent heterogeneity of CSOs and the impact of multi-source contaminants discharged into aquatic environments.It emphasizes refining emission boundary definitions,novel accounting practices adapting data-driven methods,and comprehensive management strategies in line with the move toward carbon neutrality in the UDS.It advocates the adoption of solutions including advanced technologies and artifi-cial intelligent methods to mitigate CSO-related GHG emissions,stressing the significance of integrating low-carbon solutions and a comprehensive data-driven management framework in future research directions.展开更多
In this paper, a Hierarchical Cellular System (HCS) supporting two classes of users with high and low velocity is considered. Based on the analytical model of the bidirectional calloverflow scheme, a new dynamic guard...In this paper, a Hierarchical Cellular System (HCS) supporting two classes of users with high and low velocity is considered. Based on the analytical model of the bidirectional calloverflow scheme, a new dynamic guard channel assignment method is proposed In this method, the number of guard channels in both macrocells and microcells varies in realtime according to the different call traffic load in the HCS, and as a result, the lowest dissatisfaction grade of users is achieved.展开更多
The author affiliation and the funding information in the Acknowledgement section of the online version of the original article was revised.One affiliation(the 8th affiliation)of the first author is added.The Acknowle...The author affiliation and the funding information in the Acknowledgement section of the online version of the original article was revised.One affiliation(the 8th affiliation)of the first author is added.The Acknowledgement section of the original article has been revised to:Acknowledgments:This research was funded by the National University of Mongolia under grant agreement P2023(grant number P2023-4578)and supported by the Chey Institute for Advanced Studies“International Scholarship Exchange Fellowship for the academic year of 2024-2025”,Republic of Korea,and the National University of Mongolia.We would like to acknowledge the National University of Mongolia and Soumik Das from the Center for the Study of Regional Development,Jawaharlal Nehru University,New Delhi-110067,for his valuable assistance in preparing the geological maps.展开更多
At the late stage of solidification with ultrasonic treatment （UST） in Al-Si alloys, a part of semisolid overflows and climbs along the probe. The interesting phenomenon and its influence on the solidification micro...At the late stage of solidification with ultrasonic treatment （UST） in Al-Si alloys, a part of semisolid overflows and climbs along the probe. The interesting phenomenon and its influence on the solidification microstructure were investigated in order to better study the mechanism of UST. It is considered that the overflowing phenomenon occurs due to the changes of vibration and flow in the remaining semisolid. Because the overflowed portion comes from the region with intense UST effect and vibrates with the probe during solidification, great modification of primary and euteetic Si （about 10 pm in length） and refinement of primary a（Al） （about 70 μm in size） are observed in this portion.展开更多
A simplified integer overflow detection method based on path relaxation is described for avoiding buffer overflow triggered by integer overflow. When the integer overflow refers to the size of the buffer allocated dyn...A simplified integer overflow detection method based on path relaxation is described for avoiding buffer overflow triggered by integer overflow. When the integer overflow refers to the size of the buffer allocated dynamically, this kind of integer overflow is most likely to trigger buffer overflow. Based on this discovery, through lightly static program analysis, the solution traces the key variables referring to the size of a buffer allocated dynamically and it maintains the upper bound and lower bound of these variables. After the constraint information of these traced variables is inserted into the original program, this method tests the program with test cases through path relaxation, which means that it not only reports the errors revealed by the current runtime value of traced variables contained in the test case, but it also examines the errors possibly occurring under the same execution path with all the possible values of the traced variables. The effectiveness of this method is demonstrated in a case study. Compared with the traditional buffer overflow detection methods, this method reduces the burden of detection and improves efficiency.展开更多
For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention....For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention. In this study, a water hammer protection scheme combined with an overflow surge tank and a regulating valve was developed. A mathematical model of the overflow surge tank was developed, and an analytical formula for the height of the overflow surge tank was derived. Furthermore, a practical water supply project was used to evaluate the feasibility of the combined protection scheme and analyze the sensitivity of valve regulation rules. The results showed that the combined protection scheme effectively reduced the height of the surge tank, lessened the difficulties related to construction, and reduced the necessary financial investment for the project. The two-stage closing rule articulated as fast first and then slow could minimize the overflow volume of the surge tank when the power failure occurred, while the two-stage opening rule articulated as slow first and then fast could be more conducive to the safety of the water supply system when the pump started up.展开更多
After the bursting of Huiten Nor in Hoh Xil Region in September, 2011, the topic on whether the water overflowed from the Salt Lake would enter into the Chumaer River and become the northernmost source of the Yangtze ...After the bursting of Huiten Nor in Hoh Xil Region in September, 2011, the topic on whether the water overflowed from the Salt Lake would enter into the Chumaer River and become the northernmost source of the Yangtze River has aroused wide concern from public and academic field. Based on Landsat TM/ETM+/OLI remote sensing images during 2010–2015, SRTM 1 arc-second data, Google Earth elevation data and the observation data from the Wudaoliang meteorological station, the study initially analyzed the variations of the Salt Lake and its overflowing condition and probability. The results showed that the area of the Salt Lake expanded sharply from October 2011 to April 2013, and then it stepped into a stable expansion period. On October 27, 2015, the area of the Salt Lake had arrived at 151.38 km^2, which was about 3.35 times the area of the lake on March 3, 2010. The Salt Lake will overflow when its area reaches the range from 218.90 km^2 to 220.63 km^2. Due to the differences between SRTM DEM and Google Earth elevation data, the water level of the Salt Lake simulated would be 12 m or 9.6 m higher than the current level when the lake overflowed, and its reservoir capacity would increase by 23.71 km^3 or 17.27 km^3, respectively. Meanwhile, the overflowed water of the Salt Lake would run into the Qingshui River basin from its eastern part. Although the Salt Lake does not overflow in the coming decade, with watershed expansion of the Salt Lake and the projected precipitation increase in Hoh Xil region, the probability of water overflow from the Salt Lake and becoming a tributary of the Yangtze River will exist in the long term.展开更多
Writable XOR executable （W⊕X） and address space layout randomisation （ASLR） have elevated the understanding necessary to perpetrate buffer overflow exploits [1] . However, they have not proved to be a panacea [1 ...Writable XOR executable （W⊕X） and address space layout randomisation （ASLR） have elevated the understanding necessary to perpetrate buffer overflow exploits [1] . However, they have not proved to be a panacea [1 3] , and so other mechanisms, such as stack guards and prelinking, have been introduced. In this paper, we show that host-based protection still does not offer a complete solution. To demonstrate the protection inadequacies, we perform an over the network brute force return-to-libc attack against a preforking concurrent server to gain remote access to a shell. The attack defeats host protection including W⊕X and ASLR. We then demonstrate that deploying a network intrusion detection systems （NIDS） with appropriate signatures can detect this attack efficiently.展开更多
On the basis of the latest version of a U.S. Navy generalized digital environment model （GDEM-V3.0） and World Ocean Atlas （WOA13）, the hydraulic theory is revisited and applied to the Luzon Strait, providing a fre...On the basis of the latest version of a U.S. Navy generalized digital environment model （GDEM-V3.0） and World Ocean Atlas （WOA13）, the hydraulic theory is revisited and applied to the Luzon Strait, providing a fresh look at the deepwater overflow there. The result reveals that： （1） the persistent density difference between two sides of the Luzon Strait sustains an all year round deepwater overflow from the western Pacific to the South China Sea （SCS）; （2） the seasonal variability of the deepwater overflow is influenced not only by changes in the density difference between two sides of the Luzon Strait, but also by changes in its upstream layer thickness; （3） the deepwater overflow in the Luzon Strait shows a weak semiannual variability; （4） the seasonal mean circulation pattern in the SCS deep basin does not synchronously respond to the seasonality of the deepwater overflow in the Luzon Strait. Moreover, the deepwater overflow reaches its seasonal maximum in December （based on GDEM-V3.0） or in fall （October-December, based on the WOA13）, accompanied by the lowest temperature of the year on the Pacific side of the Luzon Strait. The seasonal variability of the deepwater overflow is consistent with the existing longest （3.5 a） continuous observation along the major deepwater passage of the Luzon Strait.展开更多
基金supported by the National Natural Science Foun-dation of China(52325001,52170009,and 52400114)the National Key Research and Development Program of China(2021YFC3200700 and 2021YFC3200702)+1 种基金the Program of Shanghai Academic Research Leader,China(21XD1424000)the Fundamental Research Funds for the Central Universities.
文摘Climate change is accelerating globally,raising significant concerns regarding the environmental risks associated with combined sewer overflows(CSOs).These rainfall events lead to the excessive discharge of multiple pollutants into natural waters.However,greenhouse gas(GHG)emissions from CSOs,which are crucial for carbon neutrality in urban water systems,remain fragmented.Using the life-cycle assess-ment method expansion approach,this study breaks down the formation and discharge processes of CSOs and uncovers the underlying mechanisms driving GHG emissions during each period.Given the complex-ity and uncertainty in the spatial distribution of GHG emissions from CSOs,the development of standard monitoring and estimation methods is vital.This study identifies the factors influencing GHG emissions within the urban drainage system(UDS)and defines the interactive GHG emission boundaries and accounting framework related to CSOs.This framework is expanded to consider the hybrid nature of urban engineering and hydraulic interactions during the CSO events.Advanced modeling technologies have emerged as essential tools for predicting and managing GHG emissions from CSOs.This review pro-motes comprehensive data-driven methods for predicting GHG emissions from CSOs,fully considering the inherent heterogeneity of CSOs and the impact of multi-source contaminants discharged into aquatic environments.It emphasizes refining emission boundary definitions,novel accounting practices adapting data-driven methods,and comprehensive management strategies in line with the move toward carbon neutrality in the UDS.It advocates the adoption of solutions including advanced technologies and artifi-cial intelligent methods to mitigate CSO-related GHG emissions,stressing the significance of integrating low-carbon solutions and a comprehensive data-driven management framework in future research directions.
基金Supported in part by the National Natural Science Foundation of China(No.69825102)
文摘In this paper, a Hierarchical Cellular System (HCS) supporting two classes of users with high and low velocity is considered. Based on the analytical model of the bidirectional calloverflow scheme, a new dynamic guard channel assignment method is proposed In this method, the number of guard channels in both macrocells and microcells varies in realtime according to the different call traffic load in the HCS, and as a result, the lowest dissatisfaction grade of users is achieved.
文摘The author affiliation and the funding information in the Acknowledgement section of the online version of the original article was revised.One affiliation(the 8th affiliation)of the first author is added.The Acknowledgement section of the original article has been revised to:Acknowledgments:This research was funded by the National University of Mongolia under grant agreement P2023(grant number P2023-4578)and supported by the Chey Institute for Advanced Studies“International Scholarship Exchange Fellowship for the academic year of 2024-2025”,Republic of Korea,and the National University of Mongolia.We would like to acknowledge the National University of Mongolia and Soumik Das from the Center for the Study of Regional Development,Jawaharlal Nehru University,New Delhi-110067,for his valuable assistance in preparing the geological maps.
基金Project(50874022)supported by the National Natural Science Foundation of China
文摘At the late stage of solidification with ultrasonic treatment （UST） in Al-Si alloys, a part of semisolid overflows and climbs along the probe. The interesting phenomenon and its influence on the solidification microstructure were investigated in order to better study the mechanism of UST. It is considered that the overflowing phenomenon occurs due to the changes of vibration and flow in the remaining semisolid. Because the overflowed portion comes from the region with intense UST effect and vibrates with the probe during solidification, great modification of primary and euteetic Si （about 10 pm in length） and refinement of primary a（Al） （about 70 μm in size） are observed in this portion.
基金The National Natural Science Foundation of China (No.60873050,60703086)the Opening Foundation of State Key Laboratory of Software Engineering in Wuhan University (No.SKLSE20080717)
文摘A simplified integer overflow detection method based on path relaxation is described for avoiding buffer overflow triggered by integer overflow. When the integer overflow refers to the size of the buffer allocated dynamically, this kind of integer overflow is most likely to trigger buffer overflow. Based on this discovery, through lightly static program analysis, the solution traces the key variables referring to the size of a buffer allocated dynamically and it maintains the upper bound and lower bound of these variables. After the constraint information of these traced variables is inserted into the original program, this method tests the program with test cases through path relaxation, which means that it not only reports the errors revealed by the current runtime value of traced variables contained in the test case, but it also examines the errors possibly occurring under the same execution path with all the possible values of the traced variables. The effectiveness of this method is demonstrated in a case study. Compared with the traditional buffer overflow detection methods, this method reduces the burden of detection and improves efficiency.
基金supported by the National Natural Science Foundation of China(Grants No.52179062 and 51879087).
文摘For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention. In this study, a water hammer protection scheme combined with an overflow surge tank and a regulating valve was developed. A mathematical model of the overflow surge tank was developed, and an analytical formula for the height of the overflow surge tank was derived. Furthermore, a practical water supply project was used to evaluate the feasibility of the combined protection scheme and analyze the sensitivity of valve regulation rules. The results showed that the combined protection scheme effectively reduced the height of the surge tank, lessened the difficulties related to construction, and reduced the necessary financial investment for the project. The two-stage closing rule articulated as fast first and then slow could minimize the overflow volume of the surge tank when the power failure occurred, while the two-stage opening rule articulated as slow first and then fast could be more conducive to the safety of the water supply system when the pump started up.
基金National Natural Science Foundation of China,No.41261016,No.41561016Opening Foundation Projection of State Key Laboratory of Cryosphere Sciences,CAS,No.SKLCS-OP-2016-10Youth Scholar Scientific Capability Promoting Project of Northwest Normal University,No.NWNU-LKQN-14-4
文摘After the bursting of Huiten Nor in Hoh Xil Region in September, 2011, the topic on whether the water overflowed from the Salt Lake would enter into the Chumaer River and become the northernmost source of the Yangtze River has aroused wide concern from public and academic field. Based on Landsat TM/ETM+/OLI remote sensing images during 2010–2015, SRTM 1 arc-second data, Google Earth elevation data and the observation data from the Wudaoliang meteorological station, the study initially analyzed the variations of the Salt Lake and its overflowing condition and probability. The results showed that the area of the Salt Lake expanded sharply from October 2011 to April 2013, and then it stepped into a stable expansion period. On October 27, 2015, the area of the Salt Lake had arrived at 151.38 km^2, which was about 3.35 times the area of the lake on March 3, 2010. The Salt Lake will overflow when its area reaches the range from 218.90 km^2 to 220.63 km^2. Due to the differences between SRTM DEM and Google Earth elevation data, the water level of the Salt Lake simulated would be 12 m or 9.6 m higher than the current level when the lake overflowed, and its reservoir capacity would increase by 23.71 km^3 or 17.27 km^3, respectively. Meanwhile, the overflowed water of the Salt Lake would run into the Qingshui River basin from its eastern part. Although the Salt Lake does not overflow in the coming decade, with watershed expansion of the Salt Lake and the projected precipitation increase in Hoh Xil region, the probability of water overflow from the Salt Lake and becoming a tributary of the Yangtze River will exist in the long term.
基金supported by National Natural Science Foundation of China (No. 60873208)
文摘Writable XOR executable （W⊕X） and address space layout randomisation （ASLR） have elevated the understanding necessary to perpetrate buffer overflow exploits [1] . However, they have not proved to be a panacea [1 3] , and so other mechanisms, such as stack guards and prelinking, have been introduced. In this paper, we show that host-based protection still does not offer a complete solution. To demonstrate the protection inadequacies, we perform an over the network brute force return-to-libc attack against a preforking concurrent server to gain remote access to a shell. The attack defeats host protection including W⊕X and ASLR. We then demonstrate that deploying a network intrusion detection systems （NIDS） with appropriate signatures can detect this attack efficiently.
基金The National Natural Science Foundation of China(NSFC)-Shandong Joint Fund for Marine Science Research Centers of China under contract No.U1606405the National Basic Research Program(973 Program) of China under contract No.2011CB403502+2 种基金the National High Technology Research and Development Program(863 Program) of China under contract No.2013AA09A506the National Program on Global Change and Air-Sea Interaction under contract Nos GASI-IPOVAI-01-02 and GASI-03-01-01-04the National Natural Science Foundation of China under contract No.41606040
文摘On the basis of the latest version of a U.S. Navy generalized digital environment model （GDEM-V3.0） and World Ocean Atlas （WOA13）, the hydraulic theory is revisited and applied to the Luzon Strait, providing a fresh look at the deepwater overflow there. The result reveals that： （1） the persistent density difference between two sides of the Luzon Strait sustains an all year round deepwater overflow from the western Pacific to the South China Sea （SCS）; （2） the seasonal variability of the deepwater overflow is influenced not only by changes in the density difference between two sides of the Luzon Strait, but also by changes in its upstream layer thickness; （3） the deepwater overflow in the Luzon Strait shows a weak semiannual variability; （4） the seasonal mean circulation pattern in the SCS deep basin does not synchronously respond to the seasonality of the deepwater overflow in the Luzon Strait. Moreover, the deepwater overflow reaches its seasonal maximum in December （based on GDEM-V3.0） or in fall （October-December, based on the WOA13）, accompanied by the lowest temperature of the year on the Pacific side of the Luzon Strait. The seasonal variability of the deepwater overflow is consistent with the existing longest （3.5 a） continuous observation along the major deepwater passage of the Luzon Strait.
