Calculations and analyses are made for the ultimate composition of 158 Chinese power coals. The results reveal that the carbon content on as received basis, Cr, increases linearly with the increase of the low heating ...Calculations and analyses are made for the ultimate composition of 158 Chinese power coals. The results reveal that the carbon content on as received basis, Cr, increases linearly with the increase of the low heating value Qnot,a, on as received basis; the hydrogen content on as received basis, Hr, first increases with the increase of the volatile content on dry ash free basis Vdaf (Vdaf 〈 33.0%) and then decreases (Vdaf 〉 33.0%); the oxygen content on as received basis, Oar, increases linearly with the increase of Vau, ranging between 2.0% and 12.5%. By comparison, the nitrogen content on as received basis N of bituminous and lean coal is higher, while the sulfur content on as received basis Sar Of anthracite is higher than bituminous coal, lean coal and lignite. The hydrogen on as received basis Hr is important for the conversion between low heating value and high heating value on as received basis for Chinese power coals, and Sr is important for the calculation of high heating value from the oxygen bomb heat value for Chinese power coals.展开更多
Using the recent compilation of the isotopic composition data of surface snow of Antarctic ice sheet, we proposed an improved interpolation method of δD, which utilizes geographical factors (i.e., latitude and altit...Using the recent compilation of the isotopic composition data of surface snow of Antarctic ice sheet, we proposed an improved interpolation method of δD, which utilizes geographical factors (i.e., latitude and altitude) as the primary predictors and incorporates inverse distance weighting (IDW) technique. The method was applied to a high-resolution digital elevation model (DEM) to produce a grid map of multi-year mean δD values with lkm spatial resolution for Antarctica. The mean absolute deviation between observed and estimated data in the map is about 5.4‰, and the standard deviation is 9‰. The resulting δD pattern resembles well known characteristics such as the depletion of the heavy isotopes with increasing latitude and distance from coast line, but also reveals the complex topographic effects.展开更多
Issues specific to older migrants moving country are not yet fully understood as there are few studies on this age group. These migrants are most likely to be caught in attending to the needs of their children or thei...Issues specific to older migrants moving country are not yet fully understood as there are few studies on this age group. These migrants are most likely to be caught in attending to the needs of their children or their elderly parents, both requiring support. Over a period of two years, 35 older Polish migrants were interviewed and they told their stories of the migration experience. It was found that they had to make choices and were faced with quite difficult decisions on whether they were going to leave children or parents in Poland while they were forced into a position where they had to find work outside their own country due to age discrimination. Both men and women expressed feelings of guilt at leaving sick parents, and at not being able to afford to travel back to Poland more regularly to be with their families. Without effective cost or free digital technology, these families would not be able to sustain communication channels and relationships would break down. Consequently both the economic and emotional costs to these families and the communities in which they live could be very high.展开更多
Computer system's runtime information is an essential part of the digital evidence. Current digital forensic approaches mainly focus on memory and I/O data, while the runtime instructions from processes are often ign...Computer system's runtime information is an essential part of the digital evidence. Current digital forensic approaches mainly focus on memory and I/O data, while the runtime instructions from processes are often ignored. We present a novel approach on runtime instruction forensic analysis and have developed a forensic system which collects instruction flow and extracts digital evidence. The system is based on whole-system emulation technique and analysts are allowed to define analysis strategy to improve analysis efficiency and reduce overhead. This forensic approach and system are applicable to binary code analysis, information retrieval and matware forensics.展开更多
In this paper, we present life and scientific work of Dr. Milog Radojcic (1903-1975), the professor of the University of Belgrade and corresponding member of the Serbian Academy of Science and Arts. In the backgroun...In this paper, we present life and scientific work of Dr. Milog Radojcic (1903-1975), the professor of the University of Belgrade and corresponding member of the Serbian Academy of Science and Arts. In the background of all of Radojcic's scientific works were the doctrine of anthroposophy and geometry as its essential part. It led him to, at the time, most contemporary problems in mathematics and mathematical physics. His interest in Medieval art reveals a personality capable to unify by itself artistic and scientific worldview. His published works were digitized in 2008 at the Mathematical Institute of the Serbian Academy of Sciences and Arts and exhibited as a part of the virtual library of the National Center for Digitization. Some of his papers, both published and unpublished ones, are extremly actual and their republishing could be very important not only for scientific but also for general public as well展开更多
A 3D numerical model considering the soil-structure interaction is presented in this paper to examine the ground movement and internal force during the construction of Qingdao North Metro Station, China with a special...A 3D numerical model considering the soil-structure interaction is presented in this paper to examine the ground movement and internal force during the construction of Qingdao North Metro Station, China with a special focus on the convex effect of the crossing excavation. The influence of intersection angles and soil resilience characteristics on deformation behavior is discussed, and the suitability of two alternative constitutive models applied in excavation simulation is also considered. The analysis results show that a notable convex effect appears to be associated with the crossing excavation, and the intersection is the key area requiring special attention. The displacements at the comer decrease with increasing crossing angles. The axial loads of struts along the retaining pile wall are unequal, and the values near the cross section are generally larger than the average loads of the left-sided ones. The modified Cam-Clay (MCC) model, which is capable of describing the loading-unloading criterion and identifying the stiffness difference of strain hardening between loading and unloading, can yield a relatively high accuracy of estimation for the behavior of excavations in comparison to the Mohr-Coulomb (MC) model. Furthermore, slight soil deformation resilience after unloading can reduce the ground surface settlement and enhance the ground stability.展开更多
文摘Calculations and analyses are made for the ultimate composition of 158 Chinese power coals. The results reveal that the carbon content on as received basis, Cr, increases linearly with the increase of the low heating value Qnot,a, on as received basis; the hydrogen content on as received basis, Hr, first increases with the increase of the volatile content on dry ash free basis Vdaf (Vdaf 〈 33.0%) and then decreases (Vdaf 〉 33.0%); the oxygen content on as received basis, Oar, increases linearly with the increase of Vau, ranging between 2.0% and 12.5%. By comparison, the nitrogen content on as received basis N of bituminous and lean coal is higher, while the sulfur content on as received basis Sar Of anthracite is higher than bituminous coal, lean coal and lignite. The hydrogen on as received basis Hr is important for the conversion between low heating value and high heating value on as received basis for Chinese power coals, and Sr is important for the calculation of high heating value from the oxygen bomb heat value for Chinese power coals.
基金Under the auspices of National Natural Science Foundation of China (No. 40825017, 40576001)100 Talents Project of Chinese Academy of SciencesNational Key Technologies R&D Program of China (No. 2006BAB18B01)
文摘Using the recent compilation of the isotopic composition data of surface snow of Antarctic ice sheet, we proposed an improved interpolation method of δD, which utilizes geographical factors (i.e., latitude and altitude) as the primary predictors and incorporates inverse distance weighting (IDW) technique. The method was applied to a high-resolution digital elevation model (DEM) to produce a grid map of multi-year mean δD values with lkm spatial resolution for Antarctica. The mean absolute deviation between observed and estimated data in the map is about 5.4‰, and the standard deviation is 9‰. The resulting δD pattern resembles well known characteristics such as the depletion of the heavy isotopes with increasing latitude and distance from coast line, but also reveals the complex topographic effects.
文摘Issues specific to older migrants moving country are not yet fully understood as there are few studies on this age group. These migrants are most likely to be caught in attending to the needs of their children or their elderly parents, both requiring support. Over a period of two years, 35 older Polish migrants were interviewed and they told their stories of the migration experience. It was found that they had to make choices and were faced with quite difficult decisions on whether they were going to leave children or parents in Poland while they were forced into a position where they had to find work outside their own country due to age discrimination. Both men and women expressed feelings of guilt at leaving sick parents, and at not being able to afford to travel back to Poland more regularly to be with their families. Without effective cost or free digital technology, these families would not be able to sustain communication channels and relationships would break down. Consequently both the economic and emotional costs to these families and the communities in which they live could be very high.
文摘Computer system's runtime information is an essential part of the digital evidence. Current digital forensic approaches mainly focus on memory and I/O data, while the runtime instructions from processes are often ignored. We present a novel approach on runtime instruction forensic analysis and have developed a forensic system which collects instruction flow and extracts digital evidence. The system is based on whole-system emulation technique and analysts are allowed to define analysis strategy to improve analysis efficiency and reduce overhead. This forensic approach and system are applicable to binary code analysis, information retrieval and matware forensics.
文摘In this paper, we present life and scientific work of Dr. Milog Radojcic (1903-1975), the professor of the University of Belgrade and corresponding member of the Serbian Academy of Science and Arts. In the background of all of Radojcic's scientific works were the doctrine of anthroposophy and geometry as its essential part. It led him to, at the time, most contemporary problems in mathematics and mathematical physics. His interest in Medieval art reveals a personality capable to unify by itself artistic and scientific worldview. His published works were digitized in 2008 at the Mathematical Institute of the Serbian Academy of Sciences and Arts and exhibited as a part of the virtual library of the National Center for Digitization. Some of his papers, both published and unpublished ones, are extremly actual and their republishing could be very important not only for scientific but also for general public as well
基金Project (No. 2007AA11Z134) supported by the National High-Tech R&D Program (863) of China
文摘A 3D numerical model considering the soil-structure interaction is presented in this paper to examine the ground movement and internal force during the construction of Qingdao North Metro Station, China with a special focus on the convex effect of the crossing excavation. The influence of intersection angles and soil resilience characteristics on deformation behavior is discussed, and the suitability of two alternative constitutive models applied in excavation simulation is also considered. The analysis results show that a notable convex effect appears to be associated with the crossing excavation, and the intersection is the key area requiring special attention. The displacements at the comer decrease with increasing crossing angles. The axial loads of struts along the retaining pile wall are unequal, and the values near the cross section are generally larger than the average loads of the left-sided ones. The modified Cam-Clay (MCC) model, which is capable of describing the loading-unloading criterion and identifying the stiffness difference of strain hardening between loading and unloading, can yield a relatively high accuracy of estimation for the behavior of excavations in comparison to the Mohr-Coulomb (MC) model. Furthermore, slight soil deformation resilience after unloading can reduce the ground surface settlement and enhance the ground stability.