Presence of fine dust in air causes serious health hazard for mine operators resulting in such serious problems as coal workers’pneumoconiosis and silicosis.Major sources of dust appear of course along the mining fac...Presence of fine dust in air causes serious health hazard for mine operators resulting in such serious problems as coal workers’pneumoconiosis and silicosis.Major sources of dust appear of course along the mining face where the minerals are extracted.Proper control and management are required to ensure safe working environment in the mine.Here,we utilize the computational fluid dynamic(CFD)approach to evaluate various methods used for mitigating dust dispersion from the mining face and for ensuring safe level of dust concentration in the mine tunnel for safety of the operators.The methods used include:application of blowing and exhaust fans,application of brattice and combination of both.The results suggest that among the examined methods,implementation of appropriately located brattice to direct the flow from the main shaft to the mining face is the most effective method to direct dust particles away from the mining face.展开更多
Watermariding system is a complex system requiring both expertise and specialized techniques with security concems.Thus to relieve the multimedia manufactures of the complexities of desgning complicated watermarking s...Watermariding system is a complex system requiring both expertise and specialized techniques with security concems.Thus to relieve the multimedia manufactures of the complexities of desgning complicated watermarking systems,this paper presents a new watermarking model in which watermaiking is provided as a kind of service by the specialized watermarking companies.In order to make this service model work,a simple permutation scheme to hide the true contents is proposed.The paper also proves the security of the scheme against the attacks from the watermarking companies.Finally ,the effectiveness of the scheme is demonstrated through experiments.展开更多
Gas hydrates-the firm crystal connections formed water(water,ice,water vapor)and low-molecular waterproof natural gases(mainly methane)whose crystal structure effectively compresses gas:each cubic meter of hydrate can...Gas hydrates-the firm crystal connections formed water(water,ice,water vapor)and low-molecular waterproof natural gases(mainly methane)whose crystal structure effectively compresses gas:each cubic meter of hydrate can yield over 160 m3 of methane.In present time exploitation of the Messoyahsk(Russia)and Mallik(Canada)deposits of gas hydrates in is conducted actively.The further perfection of prospecting methods in the field of studying gas hydrates containing sediments in round extent depends on improvement of geophysical and well test research,among which native-state core drilling is one of the major.Sampling native-state core from gas hydrates sediments keeping not only original composition,but structural-textural features of their construction.Despite of appeal of use gas hydrates as the perspective and ecologically pure fuel possessing huge resources,investigation and development of their deposits can lead to a number of the negative consequences connected with arising hazards for maintenance of their technical and ecological safety of carrying out.Scales of arising problems can change from local up to regional and even global.展开更多
Water is contaminated mainly by chemical, physical and biological pollutants. At present, domestic reports on biological pollution of water environment are much less. Biological pollution in water environment pollutio...Water is contaminated mainly by chemical, physical and biological pollutants. At present, domestic reports on biological pollution of water environment are much less. Biological pollution in water environment pollution which is stable and infectious is the main part of water pollution. To fastly and accuratly detecte biological contamination of the water environment is extremely important for the control of disease outbreaks and water quality protection and public health security. This paper systematically introduces the research progress in biological water environment pollution detection methods in molecular biology aquatic environment, and explore molecular biology methods in the detection of biological contamination in water environment problems and trends.展开更多
Conventional waste management practices focusing principally on waste collection, treatment and disposal or even minimisation often prove insufficient to address resource management challenges in a sustainable manner....Conventional waste management practices focusing principally on waste collection, treatment and disposal or even minimisation often prove insufficient to address resource management challenges in a sustainable manner. Taking into account the relationship between water provision, energy security and resource efficiency, a systems approach that delivers a strong information basis and provides opportunities for resource use optimisation at various levels of application provides opportunities for synergies that could deliver real benefits when cross-sectoral solutions are applied. By-products from sewage treatment in combination with organic solid waste such as food waste can provide a valuable source of energy if managed properly and utilised effectively. This way, waste can be seen as a raw material than can be turned into a resource rather than simply be discarded. As such, AD （anaerobic digestion）, the co-digestion of food waste with sewage sludge, could become a strategic and cross-sectoral solution, if carefully applied, with the potential to convey beneficial synergies for the water and the waste industries. However, barriers to the development of such systems are diverse and often interlinked. Institutional frameworks, decision making constraints, and regulatory boundaries might still appear to require an answer for three different problems, but this can be overcome if presented as just three different parts of the same answer. Such synergies could deliver economic benefits from the additional renewable energy generated and its associated incentives, and savings on costs for the infrastructure required for the exclusive digestion of food waste.展开更多
The rise of personalized flexible electronics has promoted the rapid development of flexible supercapacitors due to their long service life,fast charging-discharging rates and safe operation.Different from the traditi...The rise of personalized flexible electronics has promoted the rapid development of flexible supercapacitors due to their long service life,fast charging-discharging rates and safe operation.Different from the traditional flexible supercapacitors,the all-in-one integrated flexible supercapacitors are more resistant to deformation and lower interface resistance,which have a broader application prospect in the field of flexible electronics.This review briefly summarizes the preparation methods and electrochemical properties of some typical all-in-one supercapacitors,represented by planar and fibrous structures in recent years.Firstly,the basic understanding of traditional flexible supercapacitors and all-in-one integrated flexible supercapacitors,and the key parameters of the performance of flexible supercapacitors are introduced.Subsequently,the hydrogel matrix all-in-one supercapacitors with different functional characteristics(stretchable,self-healing and compressible)and the nonhydrogel matrix(separator,flexible membrane)all-in-one supercapacitors are discussed.Furthermore,the challenges and future development of flexible supercapacitors are considered.展开更多
Nowadays, more and more digitalized spatial data are sold and transmitted on the Internet. Thus, there arises an important issue about copyright protection of the digital data. To solve this problem, this paper has de...Nowadays, more and more digitalized spatial data are sold and transmitted on the Internet. Thus, there arises an important issue about copyright protection of the digital data. To solve this problem, this paper has designed and implemented a spatial data watermarking service (SDWS) system which can provide a secure framework for data transaction and transfer via the Internet and protect the rights of both copyright owners and consumers at the same time.展开更多
基金financially supported by the Singapore Economic Development Board (EDB) through Minerals Metals and Materials Technology Centre (M3TC) (No.R261501013414)
文摘Presence of fine dust in air causes serious health hazard for mine operators resulting in such serious problems as coal workers’pneumoconiosis and silicosis.Major sources of dust appear of course along the mining face where the minerals are extracted.Proper control and management are required to ensure safe working environment in the mine.Here,we utilize the computational fluid dynamic(CFD)approach to evaluate various methods used for mitigating dust dispersion from the mining face and for ensuring safe level of dust concentration in the mine tunnel for safety of the operators.The methods used include:application of blowing and exhaust fans,application of brattice and combination of both.The results suggest that among the examined methods,implementation of appropriately located brattice to direct the flow from the main shaft to the mining face is the most effective method to direct dust particles away from the mining face.
基金the National Research Fund for the Doctoral Programof Higher Education of China under Grant No.20020248024
文摘Watermariding system is a complex system requiring both expertise and specialized techniques with security concems.Thus to relieve the multimedia manufactures of the complexities of desgning complicated watermarking systems,this paper presents a new watermarking model in which watermaiking is provided as a kind of service by the specialized watermarking companies.In order to make this service model work,a simple permutation scheme to hide the true contents is proposed.The paper also proves the security of the scheme against the attacks from the watermarking companies.Finally ,the effectiveness of the scheme is demonstrated through experiments.
文摘Gas hydrates-the firm crystal connections formed water(water,ice,water vapor)and low-molecular waterproof natural gases(mainly methane)whose crystal structure effectively compresses gas:each cubic meter of hydrate can yield over 160 m3 of methane.In present time exploitation of the Messoyahsk(Russia)and Mallik(Canada)deposits of gas hydrates in is conducted actively.The further perfection of prospecting methods in the field of studying gas hydrates containing sediments in round extent depends on improvement of geophysical and well test research,among which native-state core drilling is one of the major.Sampling native-state core from gas hydrates sediments keeping not only original composition,but structural-textural features of their construction.Despite of appeal of use gas hydrates as the perspective and ecologically pure fuel possessing huge resources,investigation and development of their deposits can lead to a number of the negative consequences connected with arising hazards for maintenance of their technical and ecological safety of carrying out.Scales of arising problems can change from local up to regional and even global.
文摘Water is contaminated mainly by chemical, physical and biological pollutants. At present, domestic reports on biological pollution of water environment are much less. Biological pollution in water environment pollution which is stable and infectious is the main part of water pollution. To fastly and accuratly detecte biological contamination of the water environment is extremely important for the control of disease outbreaks and water quality protection and public health security. This paper systematically introduces the research progress in biological water environment pollution detection methods in molecular biology aquatic environment, and explore molecular biology methods in the detection of biological contamination in water environment problems and trends.
文摘Conventional waste management practices focusing principally on waste collection, treatment and disposal or even minimisation often prove insufficient to address resource management challenges in a sustainable manner. Taking into account the relationship between water provision, energy security and resource efficiency, a systems approach that delivers a strong information basis and provides opportunities for resource use optimisation at various levels of application provides opportunities for synergies that could deliver real benefits when cross-sectoral solutions are applied. By-products from sewage treatment in combination with organic solid waste such as food waste can provide a valuable source of energy if managed properly and utilised effectively. This way, waste can be seen as a raw material than can be turned into a resource rather than simply be discarded. As such, AD （anaerobic digestion）, the co-digestion of food waste with sewage sludge, could become a strategic and cross-sectoral solution, if carefully applied, with the potential to convey beneficial synergies for the water and the waste industries. However, barriers to the development of such systems are diverse and often interlinked. Institutional frameworks, decision making constraints, and regulatory boundaries might still appear to require an answer for three different problems, but this can be overcome if presented as just three different parts of the same answer. Such synergies could deliver economic benefits from the additional renewable energy generated and its associated incentives, and savings on costs for the infrastructure required for the exclusive digestion of food waste.
基金supported by the National Key Research and Development Program of China(2017YFB0406301)the State Key Laboratory of Electrical Insulation and Power Equipment(EIPE19210)+1 种基金the 111 Project of China(B14040)the Fundamental Research Funds for the Central University。
文摘The rise of personalized flexible electronics has promoted the rapid development of flexible supercapacitors due to their long service life,fast charging-discharging rates and safe operation.Different from the traditional flexible supercapacitors,the all-in-one integrated flexible supercapacitors are more resistant to deformation and lower interface resistance,which have a broader application prospect in the field of flexible electronics.This review briefly summarizes the preparation methods and electrochemical properties of some typical all-in-one supercapacitors,represented by planar and fibrous structures in recent years.Firstly,the basic understanding of traditional flexible supercapacitors and all-in-one integrated flexible supercapacitors,and the key parameters of the performance of flexible supercapacitors are introduced.Subsequently,the hydrogel matrix all-in-one supercapacitors with different functional characteristics(stretchable,self-healing and compressible)and the nonhydrogel matrix(separator,flexible membrane)all-in-one supercapacitors are discussed.Furthermore,the challenges and future development of flexible supercapacitors are considered.
基金Supported by the National High Technology Research and Development Program of China(No.2006AA12Z210)
文摘Nowadays, more and more digitalized spatial data are sold and transmitted on the Internet. Thus, there arises an important issue about copyright protection of the digital data. To solve this problem, this paper has designed and implemented a spatial data watermarking service (SDWS) system which can provide a secure framework for data transaction and transfer via the Internet and protect the rights of both copyright owners and consumers at the same time.
