A theoretical study on the ground vibration isolation efficiency by a row of piles as passive barrier in a three-dimensional context was presented. The analysis was accomplished with the aid of integral equations gove...A theoretical study on the ground vibration isolation efficiency by a row of piles as passive barrier in a three-dimensional context was presented. The analysis was accomplished with the aid of integral equations governing Rayleigh wave scattering, used to predict the complicated Rayleigh wave field generated by a number of irregular scatters embedded in an elastic half-space. Then, the passive isolation effectiveness of a row of piles for screening Rayleigh wave was studied in detail. The effects of relevant parameters on the screening effectiveness were investigated and analyzed from the perspective of equivalence with in-filled trench. The results show that using a row of rigid piles as wave barrier is more effective than that of flexible ones, and an optimum reduction of vibration can be achieved either by increasing the size of piles or by decreasing the net spacing between the piles. Finally, based on the derived integral equation for Rayleigh wave scattering, the principle of equivalent modeling of the barrier of piles by an in-filled trench is put forward, which simplifies the analysis of vibration isolation by a row of piles.展开更多
A sustainable waste management system requires the beneficial uses of waste residues, such as sludge and incineration ashes, generated from environmental treatments. Among the use strategies, the practices of mixing h...A sustainable waste management system requires the beneficial uses of waste residues, such as sludge and incineration ashes, generated from environmental treatments. Among the use strategies, the practices of mixing hazardous metal-bearing solids with clay materials to produce ceramic products are often found with significant improvement in reducing the metal leach ability from products. However, relatively much fewer studies have clearly answered the questions of "What are the metal stabilization mechanisms other than simply the dilution effect and the encapsulation of metals?"; "What are the mineral phases of metals and how much are they in the products?"; and "How thermal conditions can effetely promote the transformations of metal-hosting mineral phases?". As many sustainability movements have increasingly promoted the adoption of those products generated from the beneficial use of waste materials, quantitative understandings of the metal incorporation efficiencies are important to facilitate the design of safe and reliable waste-to-resource strategies. Current findings on the metal incorporation mechanisms between common alumino silicates and hazardous metals (nickel, copper, and zinc) under different thermal conditions will be presented, and the results show the important role of forming aluminates and ferrites to significantly reduce the metal leach ability from the products. In the study, the technique of quantitative X-ray diffraction (QXRD) was applied to report the metal incorporation efficiencies through a 3-hour sintering process, aiming to stabilize the hazardous metals and also to turn the waste residues for usable ceramic products. Prolonged leach tests for potential metal-containing phases were carried out in acidic environments to evaluate the durability of thermally treated products. Both aluminate and ferrite spinels proved superior for thermomobilization of hazardous metals. With the information reported, this study has identified the key mechanisms of stabilizing the hazardous metals when thermally treated with common ceramic raw materials, and also demonstrates the importance of quantitative understanding in the development of a safe waste-to-resource strategy.展开更多
This paper,analyses how the Chinese writers borrowed the literary genre of detective fiction from the West,but also points out the"indigenous"features of the Chinese detective fiction during the late Qing an...This paper,analyses how the Chinese writers borrowed the literary genre of detective fiction from the West,but also points out the"indigenous"features of the Chinese detective fiction during the late Qing and early republic periods.Further,it examines why a few Chinese writers chose to reshape detective fiction-an imported literary genre-with these indigenous features.While earlier studies argue that the"old htterateurs"in modem China represented the conservative forces,I believe that these writers were in fact well aware of the impact of Western ideologies and intellectual trends on the Chinese society.Their preference of the indigenous,therefore,was not a bhnd choice but a conscious act of resistance.Unlike the"New Literature"writers'positive responses to Westem ideas,this group of writers treated Western ideas not as the way-to save the motherland.Rather,they viewed the"hegemony"of the empires with alarm,and resorted to a set of traditional Chinese cultural values for ways of precluding such hegemony.Their efforts of reshaping detective fiction by this means,I argue,sheds a new light on the cultural transformation of the Chinese society-and,more broadly,of the Asian societies-during this time.That is,such transformation figured not simply as the great triumph of the West over the Asian societies,but rather suggested a dynamic process of cultural collisions and re-creation.展开更多
Although extensive analyses of road segments and intersections located in urban road networks have examined the role of many factors that contribute to the frequency and severity of crashes, the explicit relationship ...Although extensive analyses of road segments and intersections located in urban road networks have examined the role of many factors that contribute to the frequency and severity of crashes, the explicit relationship between street pattern characteristics and traffic safety remains underexplored. Based on a zone-based Hong Kong database, the Space Syntax was used to quantify the topological characteristics of street patterns and investigate the role of street patterns and zone-related factors in zone-based traffic safety analysis. A joint probability model was adopted to analyze crash frequency and severity in an integrated modeling framework and the maximum likelihood estimation method was used to estimate the parameters. In addition to the characteristics of street patterns, speed, road geometry, land-use patterns, and temporal factors were considered. The vehicle hours was also included as an exposure proxy in the model to make crash frequency predictions. The results indicate that the joint probability model can reveal the relationship between zone-based traffic safety and various other factors, and that street pattern characteristics play an important role in crash frequency prediction.展开更多
Laboratory tests were performed on Toyoura sand specimens to investigate the relationship between degree of saturation Sr, B-value and P-wave velocity Vp. Different types of pore water （de-aired water or tap water） ...Laboratory tests were performed on Toyoura sand specimens to investigate the relationship between degree of saturation Sr, B-value and P-wave velocity Vp. Different types of pore water （de-aired water or tap water） and pore gas （air or CO2） as well as different magnitudes of back pressure were used to achieve different Sr （or B-value）. The measured relationship between B-value and Vp was not consistent with the theoretical prediction. The measurement shows that the Vp value in the specimen flushed with de-aired water is independent of B-value （or St） and is always around the one in fully saturated condition. However, the Vp value in the specimen flushed with tap water increases with B-value, but the shape of the relationship between Vp and B-value is quite different from the theoretical prediction. The possible explanation for the discrepancy between laboratory measurement and theoretical prediction lies in that the air exists in the water as air bubbles and therefore the pore fluid （air-water mixture） is heterogeneous instead of homogenous assumed in the theoretical prediction.展开更多
Araneiforms are spider-like ground patterns that are widespread in the southern polar regions of Mars.A gas erosion process driven by the seasonal sublimation of CO_(2)ice was proposed as an explanation for their form...Araneiforms are spider-like ground patterns that are widespread in the southern polar regions of Mars.A gas erosion process driven by the seasonal sublimation of CO_(2)ice was proposed as an explanation for their formation,which cannot occur on Earth due to the high climatic temperature.In this study,we propose an alternative mechanism that attrib-utes the araneiform formation to the erosion of upwelling salt water from the subsurface,relying on the identification of the first terrestrial analog found in a playa of the Qaidam Basin on the northern Tibetan Plateau.Morphological analysis indicates that the structures in the Qaidam Basin have fractal features comparable to araneiforms on Mars.A numerical model is developed to investigate the araneiform formation driven by the water-diffusion mechanism.The simulation res-ults indicate that the water-diffusion process,under varying ground conditions,may be responsible for the diverse aranei-form morphologies observed on both Earth and Mars.Our numerical simulations also demonstrate that the orientations of the saltwater diffusion networks are controlled by pre-existing polygonal cracks,which is consistent with observations of araneiforms on Mars and Earth.Our study thus suggests that a saltwater-related origin of the araneiform is possible and has significant implications for water searches on Mars.展开更多
Driven by the challenge of integrating large amount of experimental data, classification technique emerges as one of the major and popular tools in computational biology and bioinformatics research. Machine learning m...Driven by the challenge of integrating large amount of experimental data, classification technique emerges as one of the major and popular tools in computational biology and bioinformatics research. Machine learning methods, especially kernel methods with Support Vector Machines （SVMs） are very popular and effective tools. In the perspective of kernel matrix, a technique namely Eigen- matrix translation has been introduced for protein data classification. The Eigen-matrix translation strategy has a lot of nice properties which deserve more exploration. This paper investigates the major role of Eigen-matrix translation in classification. The authors propose that its importance lies in the dimension reduction of predictor attributes within the data set. This is very important when the dimension of features is huge. The authors show by numerical experiments on real biological data sets that the proposed framework is crucial and effective in improving classification accuracy. This can therefore serve as a novel perspective for future research in dimension reduction problems.展开更多
Rehabilitation is an integrated program of interventions that support individuals with disabilities and chronic health conditions to attain 'personally fulfilling, socially meaningful,
In this paper,the spline finite element method is developed to investigate free vibration problems of beams.The cubic B-spline functions are used to construct the displacement field.The assembly of elements and the in...In this paper,the spline finite element method is developed to investigate free vibration problems of beams.The cubic B-spline functions are used to construct the displacement field.The assembly of elements and the introduction of boundary conditions follow the standard finite element procedure.The results under various boundary conditions are compared with those obtained by the exact method and the finite difference method.It shows that the results are in excellent agreement with the analytical results and much more accurate than the results obtained by the finite difference method,especially for higher order modes.展开更多
Due to the extensive development in urban areas,the problematic ground has to be utilized for construction and activities. Thus,the methodologies for the ground improvement are extremely significant for the recycling ...Due to the extensive development in urban areas,the problematic ground has to be utilized for construction and activities. Thus,the methodologies for the ground improvement are extremely significant for the recycling of the problematic land. The appropriate methods can not only provide the effectiveness of ground treatment but also reduce the extra cost and labor for the future. In this paper,the common methods for the ground improvement will be presented and the ideas for the selection of such methods will be discussed as well.展开更多
基金Project(51178342)supported by the National Natural Science Foundation of ChinaProject(20130072110016)supported by Specialized Research Fund for the Doctoral Program of Higher Education,China
文摘A theoretical study on the ground vibration isolation efficiency by a row of piles as passive barrier in a three-dimensional context was presented. The analysis was accomplished with the aid of integral equations governing Rayleigh wave scattering, used to predict the complicated Rayleigh wave field generated by a number of irregular scatters embedded in an elastic half-space. Then, the passive isolation effectiveness of a row of piles for screening Rayleigh wave was studied in detail. The effects of relevant parameters on the screening effectiveness were investigated and analyzed from the perspective of equivalence with in-filled trench. The results show that using a row of rigid piles as wave barrier is more effective than that of flexible ones, and an optimum reduction of vibration can be achieved either by increasing the size of piles or by decreasing the net spacing between the piles. Finally, based on the derived integral equation for Rayleigh wave scattering, the principle of equivalent modeling of the barrier of piles by an in-filled trench is put forward, which simplifies the analysis of vibration isolation by a row of piles.
文摘A sustainable waste management system requires the beneficial uses of waste residues, such as sludge and incineration ashes, generated from environmental treatments. Among the use strategies, the practices of mixing hazardous metal-bearing solids with clay materials to produce ceramic products are often found with significant improvement in reducing the metal leach ability from products. However, relatively much fewer studies have clearly answered the questions of "What are the metal stabilization mechanisms other than simply the dilution effect and the encapsulation of metals?"; "What are the mineral phases of metals and how much are they in the products?"; and "How thermal conditions can effetely promote the transformations of metal-hosting mineral phases?". As many sustainability movements have increasingly promoted the adoption of those products generated from the beneficial use of waste materials, quantitative understandings of the metal incorporation efficiencies are important to facilitate the design of safe and reliable waste-to-resource strategies. Current findings on the metal incorporation mechanisms between common alumino silicates and hazardous metals (nickel, copper, and zinc) under different thermal conditions will be presented, and the results show the important role of forming aluminates and ferrites to significantly reduce the metal leach ability from the products. In the study, the technique of quantitative X-ray diffraction (QXRD) was applied to report the metal incorporation efficiencies through a 3-hour sintering process, aiming to stabilize the hazardous metals and also to turn the waste residues for usable ceramic products. Prolonged leach tests for potential metal-containing phases were carried out in acidic environments to evaluate the durability of thermally treated products. Both aluminate and ferrite spinels proved superior for thermomobilization of hazardous metals. With the information reported, this study has identified the key mechanisms of stabilizing the hazardous metals when thermally treated with common ceramic raw materials, and also demonstrates the importance of quantitative understanding in the development of a safe waste-to-resource strategy.
文摘This paper,analyses how the Chinese writers borrowed the literary genre of detective fiction from the West,but also points out the"indigenous"features of the Chinese detective fiction during the late Qing and early republic periods.Further,it examines why a few Chinese writers chose to reshape detective fiction-an imported literary genre-with these indigenous features.While earlier studies argue that the"old htterateurs"in modem China represented the conservative forces,I believe that these writers were in fact well aware of the impact of Western ideologies and intellectual trends on the Chinese society.Their preference of the indigenous,therefore,was not a bhnd choice but a conscious act of resistance.Unlike the"New Literature"writers'positive responses to Westem ideas,this group of writers treated Western ideas not as the way-to save the motherland.Rather,they viewed the"hegemony"of the empires with alarm,and resorted to a set of traditional Chinese cultural values for ways of precluding such hegemony.Their efforts of reshaping detective fiction by this means,I argue,sheds a new light on the cultural transformation of the Chinese society-and,more broadly,of the Asian societies-during this time.That is,such transformation figured not simply as the great triumph of the West over the Asian societies,but rather suggested a dynamic process of cultural collisions and re-creation.
基金Project(71301083)supported by the National Natural Science Foundation of ChinaProject(2012AA112305)supported by the National High-Tech Research and Development Program of China+1 种基金Project(2012CB725405)supported by the National Basic Research Program of ChinaProject(17208614)supported by the Research Grants Council of the Hong Kong Special Administrative Region,China
文摘Although extensive analyses of road segments and intersections located in urban road networks have examined the role of many factors that contribute to the frequency and severity of crashes, the explicit relationship between street pattern characteristics and traffic safety remains underexplored. Based on a zone-based Hong Kong database, the Space Syntax was used to quantify the topological characteristics of street patterns and investigate the role of street patterns and zone-related factors in zone-based traffic safety analysis. A joint probability model was adopted to analyze crash frequency and severity in an integrated modeling framework and the maximum likelihood estimation method was used to estimate the parameters. In addition to the characteristics of street patterns, speed, road geometry, land-use patterns, and temporal factors were considered. The vehicle hours was also included as an exposure proxy in the model to make crash frequency predictions. The results indicate that the joint probability model can reveal the relationship between zone-based traffic safety and various other factors, and that street pattern characteristics play an important role in crash frequency prediction.
基金Foundation item： Project（2012CB719803） supported by the National Basic Research Program of China Project（201011159098） supported by the Seed Funding for Basic Research Scheme from The University of Hong Kong, China
文摘Laboratory tests were performed on Toyoura sand specimens to investigate the relationship between degree of saturation Sr, B-value and P-wave velocity Vp. Different types of pore water （de-aired water or tap water） and pore gas （air or CO2） as well as different magnitudes of back pressure were used to achieve different Sr （or B-value）. The measured relationship between B-value and Vp was not consistent with the theoretical prediction. The measurement shows that the Vp value in the specimen flushed with de-aired water is independent of B-value （or St） and is always around the one in fully saturated condition. However, the Vp value in the specimen flushed with tap water increases with B-value, but the shape of the relationship between Vp and B-value is quite different from the theoretical prediction. The possible explanation for the discrepancy between laboratory measurement and theoretical prediction lies in that the air exists in the water as air bubbles and therefore the pore fluid （air-water mixture） is heterogeneous instead of homogenous assumed in the theoretical prediction.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB41000000)the Fundamental Research Funds for the Central Universities(WK2080000144)。
文摘Araneiforms are spider-like ground patterns that are widespread in the southern polar regions of Mars.A gas erosion process driven by the seasonal sublimation of CO_(2)ice was proposed as an explanation for their formation,which cannot occur on Earth due to the high climatic temperature.In this study,we propose an alternative mechanism that attrib-utes the araneiform formation to the erosion of upwelling salt water from the subsurface,relying on the identification of the first terrestrial analog found in a playa of the Qaidam Basin on the northern Tibetan Plateau.Morphological analysis indicates that the structures in the Qaidam Basin have fractal features comparable to araneiforms on Mars.A numerical model is developed to investigate the araneiform formation driven by the water-diffusion mechanism.The simulation res-ults indicate that the water-diffusion process,under varying ground conditions,may be responsible for the diverse aranei-form morphologies observed on both Earth and Mars.Our numerical simulations also demonstrate that the orientations of the saltwater diffusion networks are controlled by pre-existing polygonal cracks,which is consistent with observations of araneiforms on Mars and Earth.Our study thus suggests that a saltwater-related origin of the araneiform is possible and has significant implications for water searches on Mars.
基金supported by Research Grants Council of Hong Kong under Grant No.17301214HKU CERG Grants,Fundamental Research Funds for the Central Universities+2 种基金the Research Funds of Renmin University of ChinaHung Hing Ying Physical Research Grantthe Natural Science Foundation of China under Grant No.11271144
文摘Driven by the challenge of integrating large amount of experimental data, classification technique emerges as one of the major and popular tools in computational biology and bioinformatics research. Machine learning methods, especially kernel methods with Support Vector Machines （SVMs） are very popular and effective tools. In the perspective of kernel matrix, a technique namely Eigen- matrix translation has been introduced for protein data classification. The Eigen-matrix translation strategy has a lot of nice properties which deserve more exploration. This paper investigates the major role of Eigen-matrix translation in classification. The authors propose that its importance lies in the dimension reduction of predictor attributes within the data set. This is very important when the dimension of features is huge. The authors show by numerical experiments on real biological data sets that the proposed framework is crucial and effective in improving classification accuracy. This can therefore serve as a novel perspective for future research in dimension reduction problems.
文摘Rehabilitation is an integrated program of interventions that support individuals with disabilities and chronic health conditions to attain 'personally fulfilling, socially meaningful,
文摘In this paper,the spline finite element method is developed to investigate free vibration problems of beams.The cubic B-spline functions are used to construct the displacement field.The assembly of elements and the introduction of boundary conditions follow the standard finite element procedure.The results under various boundary conditions are compared with those obtained by the exact method and the finite difference method.It shows that the results are in excellent agreement with the analytical results and much more accurate than the results obtained by the finite difference method,especially for higher order modes.
文摘Due to the extensive development in urban areas,the problematic ground has to be utilized for construction and activities. Thus,the methodologies for the ground improvement are extremely significant for the recycling of the problematic land. The appropriate methods can not only provide the effectiveness of ground treatment but also reduce the extra cost and labor for the future. In this paper,the common methods for the ground improvement will be presented and the ideas for the selection of such methods will be discussed as well.
