A γ-TiAl alloy with nominal composition of Ti-47%Al（molar fraction） was directionally solidified in an alumina mould with an Y2O3 protective coating.The effects of processing parameters（melting temperature and int...A γ-TiAl alloy with nominal composition of Ti-47%Al（molar fraction） was directionally solidified in an alumina mould with an Y2O3 protective coating.The effects of processing parameters（melting temperature and interaction time） on the metal-coating interface,microstructure and chemical composition of the alloy were evaluated.The result shows that the Y2O3 protective coating exhibits an effective barrier capability to avoid direct contact between the mould base material and the TiAl melt,although the Y2O3 coating is found to suffer some erosion and be slightly dissolved by the molten TiAl due to the coating-metal interactions.The directionally solidified alloys were contaminated with Y and O,and Y2O3 inclusions were dispersed in the metal matrix.The reason for this metal contamination is the Y2O3 coating dissolution by the TiAl melt.One mode of the interaction between Y2O3 and the TiAl melt is dissolution of yttrium and atomic oxygen in the melt by reaction Y2O3（s）=2Y（in TiAl melt）＋3O（in TiAl melt）.Both the extent of alloy contamination and the volume fractions of Y2O3 inclusions depend on the melting temperature and the interaction time.展开更多
The impact of risk correlation on firm＇s investments in information system security is studied by using quantification models combining the ideas of the risk management theory and the game theory. The equilibrium lev...The impact of risk correlation on firm＇s investments in information system security is studied by using quantification models combining the ideas of the risk management theory and the game theory. The equilibrium levels of self-protection and insurance coverage under the non- cooperative condition are compared with socially optimal solutions, and the associated coordination mechanisms are proposed. The results show that self-protection investment increases in response to an increase in potential loss when the interdependent risk is small; the interdependent risk of security investments often induce firms to underinvest in security relative to the socially efficient level by ignoring marginal external costs or benefits conferred on others. A subsidy on self-protection investment from the government can help coordinate a firm＇s risk management decision and, thereby, improve individual security level and overall social welfare.展开更多
The effect of the melt holding temperature on the morphological evolution and sedimentation behavior of iron-rich intermetallics in Al-7.0 Si-1.0 Fe-1.2 Mn-0.25 Mg alloy was investigated using an optical microscope,sc...The effect of the melt holding temperature on the morphological evolution and sedimentation behavior of iron-rich intermetallics in Al-7.0 Si-1.0 Fe-1.2 Mn-0.25 Mg alloy was investigated using an optical microscope,scanning electron microscope and differential thermal analyzer.The results show that as the holding temperature decreases,the morphologies of the primary iron-rich phase in matrix change from star-like to polygonal,and the number of the primary phases gradually decreases and disappears at 615°C.Finally,the Chinese script phases with small size,high compact and uniform distribution are obtained.In contrast,the primary iron-rich phases in slag transform into a coarser polygonal shape with lower roundness,and some of them have hollow structures.Furthermore,the area fraction of intermetallics and Fe content in the matrix decrease gradually due to the formation and growth of sludge and subsequent natural sedimentation during melt holding.With the decrease of holding temperature,the main factors hindering the settlement of the primary phases are morphology,size,and density in turn.展开更多
In this paper,we study the problem of privacy-preserving top-k keyword similarity search over outsourced cloud data.Taking edit distance as a measure of similarity,we first build up the similarity keyword sets for all...In this paper,we study the problem of privacy-preserving top-k keyword similarity search over outsourced cloud data.Taking edit distance as a measure of similarity,we first build up the similarity keyword sets for all the keywords in the data collection.We then calculate the relevance scores of the elements in the similarity keyword sets by the widely used tf-idf theory.Leveraging both the similarity keyword sets and the relevance scores,we present a new secure and efficient treebased index structure for privacy-preserving top-k keyword similarity search.To prevent potential statistical attacks,we also introduce a two-server model to separate the association between the index structure and the data collection in cloud servers.Thorough analysis is given on the validity of search functionality and formal security proofs are presented for the privacy guarantee of our solution.Experimental results on real-world data sets further demonstrate the availability and efficiency of our solution.展开更多
In this paper, a new kind of symmetry and its conserved quantities of a mechanical system in phase space are studied. The definition of this new symmetry, i,e., a Noether-Mei symmetry, is presented, and the criterion ...In this paper, a new kind of symmetry and its conserved quantities of a mechanical system in phase space are studied. The definition of this new symmetry, i,e., a Noether-Mei symmetry, is presented, and the criterion of this symmetry is also given. The Noether conserved quantity and the Mei conserved quantity deduced from the Noether-Mei symmetry of the system are obtained. Finally, two examples are given to illustrate the Bpplication of the results.展开更多
A novel embedded sensor network records changes in key climatic-environmental variables over a range of altitude in the BaekduDaegan Mountain （BDM） of Gangwon Province in Korea, a protected mountain region with uniq...A novel embedded sensor network records changes in key climatic-environmental variables over a range of altitude in the BaekduDaegan Mountain （BDM） of Gangwon Province in Korea, a protected mountain region with unique biodiversity undergoing climate change research. The investigated area is subdivided into three horizontal north-south study areas. Three variables, temperature （T, °C）, relative humidity （RH, %）, and light intensity （LI, lumens m-2, or lux, lx）, have been continuously measured at hourly intervals from June, 2olo to September, 2011 using HOBO H8 devices at lO fixed study sites. These hourly observations are aggregated to monthly, seasonal and annual mean values, and results are summarized to inaugurate a long-term climate change investigation. A region wide T difference in accordance with altitude, or lapse rate, over the interval is calculated as o.4°C l00 m-1. T lapse rates change seasonally, with winter lapse rates being greater than those of summer. RH is elevated in summer compared to other seasons. LI within forestland is lower during summer and higher during other seasons. The obtained results could closely relate to the vegetation type and structure and the terrain state since data loggers were located in forestland.展开更多
Formulation of different ecological zone plans according to the corresponding protection targets and the necessity of proper conservation policy is one of the measures to achieve the goal of ecological conservation in...Formulation of different ecological zone plans according to the corresponding protection targets and the necessity of proper conservation policy is one of the measures to achieve the goal of ecological conservation in China.In order to clarify the interrelation among key ecological zone plans,this paper carried out the research on spatial relation of priority areas of biodiversity conservation and three key ecological areas(key ecological function areas,key regions of ecological service function,national nature reserves)and the research on ecological conditions,based on multi-scale ecological spatial theme information,which incorporates elements like ecological quality and type,and by the aid of spatial information analysis and GIS modeling.The results showed a contrastively fine spatial consistency with 68.8%of priority areas of biodiversity conservation overlapping with three key ecological areas.Although the environment in priority areas of biodiversity conservation were in good conditions,protection pressure is also increasing,powerful supervision and protection should not be ignored.The environmental conditions in the overlapping areas,as a whole,were superior to those in the non-overlapping areas.Since two areas have different characteristics,targeted protection measures should be formulated based on this difference,which will be very important for biodiversity conservation in priority areas of biodiversity conservation.展开更多
Open phase in three phase induction motors is a common fault that can occur as a result of a fuse blowing or a pro- tective device failing on one phase of the motor. This paper introduces a new method,which is based o...Open phase in three phase induction motors is a common fault that can occur as a result of a fuse blowing or a pro- tective device failing on one phase of the motor. This paper introduces a new method,which is based on the transient mea- surement and can distinguish the fault of one phase connecting ground. The method has been proved to be in correspondence with the simulation results by Matlab and LabVIEW in practice, The method has merits of simplicity, accuracy and ease of USe.展开更多
The present study revealed proliferation of macro-algae modifying coral reef ecosystems in a different manner due to diseases and sedimentations in the Mandapam group of islands in the Gulf of Mannar. Benthic surveys ...The present study revealed proliferation of macro-algae modifying coral reef ecosystems in a different manner due to diseases and sedimentations in the Mandapam group of islands in the Gulf of Mannar. Benthic surveys were conducted with major attack of seven coral reefs diseases with high sedimentation rate, nine species of fleshy macro-algae(Turbinaria ornata, Turbinaria conaides, Caulerpa scalpelliformis, Caulerpa racemosa, Kappaphycus alvarezii, Padina gymnosphora, Sargassum wightii, Ulva reticulata and Calurpa lentillifera) proliferation against major corals life forms(Acropora branching, Acropora digitate, Acropora tabulate, coral massive, coral submassive, coral foliose and coral encrusting). The results confirm that diseased corals most favor to macro-algae growth(15.27%) rather than the sedimentation covered corals(8.24 %). In the degradation of coral life forms, massive corals were more highly damaged(7.05%) than any other forms. Within a short period of time(May to September), coral coverage shrank to 17.4% from 21.9%, macro-algae increased 23.51% and the average sedimentation rate attained 77.52 mg cm^(-2) d^(-1) with persisting coral reef diseases of 17.59%. The Pearson correlation showed that the coral cover decreased with increasing macro-algae growth, which was statistically significant(r =-0.774, n = 100, P < 0.0005). The proliferation of the various macro-algae C. scalpellifrmis, T. ornata, C. racemosa, T. conaides, U. reticulata, S. wightii, K. alvarezii, P. gymnosphora and C. lentillifera increased with percentages of 6.0, 5.8, 5.7, 4.9, 4.2, 3.7, 2.7 and 1.9, respectively. If this trend continues, the next generation of new recruit corals will undoubtedly lead to a phase shift in Gulf of Mannar corals.展开更多
Gas hydrates are solid inclusion compounds that are composed of a three-dimensional hydrogen-bonded network of water cages that can trap small gas molecules, such as methane and carbon dioxide. Understanding the rheol...Gas hydrates are solid inclusion compounds that are composed of a three-dimensional hydrogen-bonded network of water cages that can trap small gas molecules, such as methane and carbon dioxide. Understanding the rheological properties of gas hydrate crystals in solution can he critical in a number of energy applications, including the transportation of natural gas in suhsea and onshore operations, as well as technological applications for gas separation, desalination, or sequestration. A number of exper- imental and modeling studies have been done on hydrate slurry rheology; however, the link between theory and experiment is not well-defined. This article provides a review on the current state of the art of hydrate slurry viscosity measurements from high- and low-pressure rheometer studies and high-pressure flowloops over a range of different sub-cooling （ATsub = TequiI Texp） and fluid conditions, including for water and oil continuous systems. The theoretical models that have been developed to describe the gas hydrate slurry relative viscosity are also reviewed. Perspectives＇ linkage between the experiments and theory is also discussed.展开更多
In her book, The Human Condition, Hannah Arendt states： ＂we are all the same, that is, human, in such a way that nobody is ever the same as anybody else＂ （1998, 8）. In this statement, we are the same （equality）...In her book, The Human Condition, Hannah Arendt states： ＂we are all the same, that is, human, in such a way that nobody is ever the same as anybody else＂ （1998, 8）. In this statement, we are the same （equality） and yet nobody is ever the same as anybody else （plurality）. This may sound contradictory yet what it means is that there is a common base which makes us all the same, and precisely because of this base, we are able to make comparisons and hence differentiate one from the other because we are all different. When analyzing two concepts, an equal status in at least one normatively relevant respect is needed. Where there is one, there is the other precisely because of the other and vice versa. The fact that it is only at least one respect that is needed implies the existence of other aspects that act as common distinguishing factors. Therefore, distinction implies equality. The paper will explore how according to Arendt, equality, a political concept, has been perverted into a social concept. In her view, previously, differing circumstances and conditions served as ＂protection＂ and actually had a protective role. An explanation will thus be given as to how a lack of these differences in the modem period has resulted in a challenge and how this challenge has created unexpected problems for the human condition. This implies reflexivity between political theory and the human agent, and will be presented from Arendt＇s perspective.展开更多
The entanglement of the generalized two-mode binomial states in the phase damping channel is studied by making use of the relative entropy of the entanglement. It is shown that the factors of q and p play the crucial ...The entanglement of the generalized two-mode binomial states in the phase damping channel is studied by making use of the relative entropy of the entanglement. It is shown that the factors of q and p play the crucial roles in control the relative entropy of the entanglement. Furthermore, we propose a scheme of teleporting an unknown state via the generalized two-mode binomial states, and calculate the mean fidelity of the scheme.展开更多
On the basis of the reaction rules and its influencing factors of sulfur compounds in MIP naphtha, a correlation model for describing the correlation between mass fraction of sulfur in MIP naphtha, mass fraction of su...On the basis of the reaction rules and its influencing factors of sulfur compounds in MIP naphtha, a correlation model for describing the correlation between mass fraction of sulfur in MIP naphtha, mass fraction of sulfur in feedstock and volume fraction of olefin in naphtha was developed and the model＇s parameters were estimated. The residual error distribution and statistical study showed that the developed model was reasonable and reliable and able to predict the mass fraction of sulfur compounds in naphtha. The correlation model can provide theoretical guidance and operation base for adjusting process parameters to produce EURO IV gasoline by the MIP units. The model was validated by its application on the MIP unit of Qingdao Refining ＆ Chemical Company. On this unit, the tail oil with low sulfur content obtained via hydrotreating gas oil was used as the feedstock and the olefin content of naphtha was reduced by promoting hydrogen transfer reaction through adjustment of process parameters. Thus, EURO IV clean gasoline was manufactured by this MIP unit.展开更多
The definition and criterion of the Mei symmetry of a relativistic variable mass system are given. The relation between the Mei symmetry and the Noether symmetry of the system is found under infinitesimal transformati...The definition and criterion of the Mei symmetry of a relativistic variable mass system are given. The relation between the Mei symmetry and the Noether symmetry of the system is found under infinitesimal transformations of groups. The conserved quantities to which the Mei symmetry and Noether symmetry of the system lead are obtained.An example is given to illustrate the application of the result.展开更多
The Jordan＇s NAP （national action plan） provides a set of priority actions for the conservation of marine turtles and their habitats in the Gulf of Aqaba, Red Sea. The main threats to the maintenance of stable turt...The Jordan＇s NAP （national action plan） provides a set of priority actions for the conservation of marine turtles and their habitats in the Gulf of Aqaba, Red Sea. The main threats to the maintenance of stable turtle populations in Jordan range from opportunistic capture to global threats such fishing mortality and from pollution incidents. Jordan＇s NAP addresses the primary causes of turtle mortality with a series of proposed actions. It includes reducing threats from commercial fisheries, development operations, promoting turtle rescue and rehabilitation along with public awareness activities. It considered also a set of recommendations to reflect the importance of protecting marine turtles in Jordan＇s Gulf of Aqaba. It includes community participation in conservation, capacity of national agencies to carry out management activities and to enforce legislations. To each priority actions identified in NAP, expected results and performance indicators were defined. Hence, the designation of a level of urgency to each specific priority action allowed a phased approach for implementation, subject to budget and available national capacity. Currently, NAP is performing effectively through an integrated network of national working groups including government and non-governmental organisations and other stakeholders.展开更多
We introduce a kind of number-conserving coherent state in Rindler space which can describe the quantum state of thermal particles observed in Rindler space. This is based on the Unruh effect that the thermal particle...We introduce a kind of number-conserving coherent state in Rindler space which can describe the quantum state of thermal particles observed in Rindler space. This is based on the Unruh effect that the thermal particles seen by an accelerating observer in fiat space can be seen by an inertial observer in curved space under a conformal transformation.展开更多
Quantitative structure-retention relationship （QSRR） model for the estimation of retention indices （RIs） of 39 oxygen-containing compounds containing ketones and esters was established by our newly introduced dist...Quantitative structure-retention relationship （QSRR） model for the estimation of retention indices （RIs） of 39 oxygen-containing compounds containing ketones and esters was established by our newly introduced distance-based atom-type indices DAI. The useful application of the novel DAI indices has been demonstrated by developing accurate predictive equations for gas chromatographic retention indices. The statistical results of the multiple linear regression for the final model are τ=0.9973 and s=8.23. Furthermore, an external test set of 10 oxo-containing compounds can be accurately predicted with the final equation giving the following statistical results： τpred：0.9966 and spred=8.56.展开更多
Historic cities are cultural achievements that are gradually created by inhabitants over the centuries. In developed countries, the conservation of historic cities seems to be generally acknowledged as a method of com...Historic cities are cultural achievements that are gradually created by inhabitants over the centuries. In developed countries, the conservation of historic cities seems to be generally acknowledged as a method of community development that does not depend on huge exploitation. On the other hand, no sufficient countermeasures have been taken in developing countries because most native stakeholders are still interested in development. Here the author could focus on so-called ＂international cooperation＂, but urban conservation for historic cities where inhabitants actually live is still a minor consideration except for some government-based conservation projects for monuments and isolated examples of cultural heritage. In this paper, the example was taken of a conservation project which has been carried out by JICA （Japanese International Cooperation Agency） in Damascus, the old capital of Syria. The target area for the project is ＂Qanawat South＂. Although the origin of＂Qanawat South＂ dates back to the Roman age, efforts for urban conservation have not been well organized, partly because the area is located outside of the so-called old city registered as a world heritage site. For example, the master plan of 1968 indicated the redistribution of the traditional quarters, while some conservation laws have been restricting the regeneration of the area. Moreover, there is not yet any consensus among the stakeholders concerning the historical value of the quarter, they are still questioning why the area should be conserved rather than being freely sold or developed and what and how they should contribute to conservation. Based on analysis of the actual situation of Qasr al-Hajjaj Street, this paper examines a method called ＂restoration-type＂ facade improvement adopted by JICA, for which the final goal is not only to maintain the appearance of the street but also to activate the life of the habitants of the street.展开更多
The operating mechanism refers to the structural setup, component assembly and inspection maintenance of the safeguards and its efficient operation. Health insurance management mechanism refers to the effective combin...The operating mechanism refers to the structural setup, component assembly and inspection maintenance of the safeguards and its efficient operation. Health insurance management mechanism refers to the effective combination, governance, operation, evaluation and improvement of medical service stakeholders. It is a series of institutional arrangements to effectively provide medical services and safeguard the interests of beneficiaries.＂展开更多
文摘A γ-TiAl alloy with nominal composition of Ti-47%Al（molar fraction） was directionally solidified in an alumina mould with an Y2O3 protective coating.The effects of processing parameters（melting temperature and interaction time） on the metal-coating interface,microstructure and chemical composition of the alloy were evaluated.The result shows that the Y2O3 protective coating exhibits an effective barrier capability to avoid direct contact between the mould base material and the TiAl melt,although the Y2O3 coating is found to suffer some erosion and be slightly dissolved by the molten TiAl due to the coating-metal interactions.The directionally solidified alloys were contaminated with Y and O,and Y2O3 inclusions were dispersed in the metal matrix.The reason for this metal contamination is the Y2O3 coating dissolution by the TiAl melt.One mode of the interaction between Y2O3 and the TiAl melt is dissolution of yttrium and atomic oxygen in the melt by reaction Y2O3（s）=2Y（in TiAl melt）＋3O（in TiAl melt）.Both the extent of alloy contamination and the volume fractions of Y2O3 inclusions depend on the melting temperature and the interaction time.
基金The National Natural Science Foundation of China(No.71071033)
文摘The impact of risk correlation on firm＇s investments in information system security is studied by using quantification models combining the ideas of the risk management theory and the game theory. The equilibrium levels of self-protection and insurance coverage under the non- cooperative condition are compared with socially optimal solutions, and the associated coordination mechanisms are proposed. The results show that self-protection investment increases in response to an increase in potential loss when the interdependent risk is small; the interdependent risk of security investments often induce firms to underinvest in security relative to the socially efficient level by ignoring marginal external costs or benefits conferred on others. A subsidy on self-protection investment from the government can help coordinate a firm＇s risk management decision and, thereby, improve individual security level and overall social welfare.
基金Project(2017GDASCX-0117)supported by the Guangdong Academy of Sciences,ChinaProject(201806010126)supported by the Pearl River S&T Nova Program of Guangzhou,China+3 种基金Projects(2017A050503004,2017A07071029)supported by the Guangdong Provincial Program of Science and Technology,ChinaProject(18126010)supported by the Guangxi Autonomous Regional Program of Science and Technology,ChinaProject(201802030012)supported by the Guangzhou Municipal Science and Technology Bureau,ChinaProject(2017A0109005)supported by the Sihui Plan Project of Science and Technology,China.
文摘The effect of the melt holding temperature on the morphological evolution and sedimentation behavior of iron-rich intermetallics in Al-7.0 Si-1.0 Fe-1.2 Mn-0.25 Mg alloy was investigated using an optical microscope,scanning electron microscope and differential thermal analyzer.The results show that as the holding temperature decreases,the morphologies of the primary iron-rich phase in matrix change from star-like to polygonal,and the number of the primary phases gradually decreases and disappears at 615°C.Finally,the Chinese script phases with small size,high compact and uniform distribution are obtained.In contrast,the primary iron-rich phases in slag transform into a coarser polygonal shape with lower roundness,and some of them have hollow structures.Furthermore,the area fraction of intermetallics and Fe content in the matrix decrease gradually due to the formation and growth of sludge and subsequent natural sedimentation during melt holding.With the decrease of holding temperature,the main factors hindering the settlement of the primary phases are morphology,size,and density in turn.
基金supported partly by the following funding agencies:the National Natural Science Foundation(No.61170274)the Innovative Research Groups of the National Natural Science Foundation(No.61121061)+1 种基金the National Key Basic Research Program of China (No.2011CB302506)Youth Scientific Research and Innovation Plan of Beijing University of Posts and Telecommunications(No. 2013RC1101)
文摘In this paper,we study the problem of privacy-preserving top-k keyword similarity search over outsourced cloud data.Taking edit distance as a measure of similarity,we first build up the similarity keyword sets for all the keywords in the data collection.We then calculate the relevance scores of the elements in the similarity keyword sets by the widely used tf-idf theory.Leveraging both the similarity keyword sets and the relevance scores,we present a new secure and efficient treebased index structure for privacy-preserving top-k keyword similarity search.To prevent potential statistical attacks,we also introduce a two-server model to separate the association between the index structure and the data collection in cloud servers.Thorough analysis is given on the validity of search functionality and formal security proofs are presented for the privacy guarantee of our solution.Experimental results on real-world data sets further demonstrate the availability and efficiency of our solution.
文摘In this paper, a new kind of symmetry and its conserved quantities of a mechanical system in phase space are studied. The definition of this new symmetry, i,e., a Noether-Mei symmetry, is presented, and the criterion of this symmetry is also given. The Noether conserved quantity and the Mei conserved quantity deduced from the Noether-Mei symmetry of the system are obtained. Finally, two examples are given to illustrate the Bpplication of the results.
文摘A novel embedded sensor network records changes in key climatic-environmental variables over a range of altitude in the BaekduDaegan Mountain （BDM） of Gangwon Province in Korea, a protected mountain region with unique biodiversity undergoing climate change research. The investigated area is subdivided into three horizontal north-south study areas. Three variables, temperature （T, °C）, relative humidity （RH, %）, and light intensity （LI, lumens m-2, or lux, lx）, have been continuously measured at hourly intervals from June, 2olo to September, 2011 using HOBO H8 devices at lO fixed study sites. These hourly observations are aggregated to monthly, seasonal and annual mean values, and results are summarized to inaugurate a long-term climate change investigation. A region wide T difference in accordance with altitude, or lapse rate, over the interval is calculated as o.4°C l00 m-1. T lapse rates change seasonally, with winter lapse rates being greater than those of summer. RH is elevated in summer compared to other seasons. LI within forestland is lower during summer and higher during other seasons. The obtained results could closely relate to the vegetation type and structure and the terrain state since data loggers were located in forestland.
基金Under the auspices of Public Science and Technology Research Funds of Environment(No.201009021,2011467026,2012467044)National Key Technology R&D Program of China(No.2012BAH32B03)National Natural Science Foundation of China(No.41171318,41001160)
文摘Formulation of different ecological zone plans according to the corresponding protection targets and the necessity of proper conservation policy is one of the measures to achieve the goal of ecological conservation in China.In order to clarify the interrelation among key ecological zone plans,this paper carried out the research on spatial relation of priority areas of biodiversity conservation and three key ecological areas(key ecological function areas,key regions of ecological service function,national nature reserves)and the research on ecological conditions,based on multi-scale ecological spatial theme information,which incorporates elements like ecological quality and type,and by the aid of spatial information analysis and GIS modeling.The results showed a contrastively fine spatial consistency with 68.8%of priority areas of biodiversity conservation overlapping with three key ecological areas.Although the environment in priority areas of biodiversity conservation were in good conditions,protection pressure is also increasing,powerful supervision and protection should not be ignored.The environmental conditions in the overlapping areas,as a whole,were superior to those in the non-overlapping areas.Since two areas have different characteristics,targeted protection measures should be formulated based on this difference,which will be very important for biodiversity conservation in priority areas of biodiversity conservation.
文摘Open phase in three phase induction motors is a common fault that can occur as a result of a fuse blowing or a pro- tective device failing on one phase of the motor. This paper introduces a new method,which is based on the transient mea- surement and can distinguish the fault of one phase connecting ground. The method has been proved to be in correspondence with the simulation results by Matlab and LabVIEW in practice, The method has merits of simplicity, accuracy and ease of USe.
基金the National Remote Sensing Center, ISRO-Hyderabad for providing financial supports
文摘The present study revealed proliferation of macro-algae modifying coral reef ecosystems in a different manner due to diseases and sedimentations in the Mandapam group of islands in the Gulf of Mannar. Benthic surveys were conducted with major attack of seven coral reefs diseases with high sedimentation rate, nine species of fleshy macro-algae(Turbinaria ornata, Turbinaria conaides, Caulerpa scalpelliformis, Caulerpa racemosa, Kappaphycus alvarezii, Padina gymnosphora, Sargassum wightii, Ulva reticulata and Calurpa lentillifera) proliferation against major corals life forms(Acropora branching, Acropora digitate, Acropora tabulate, coral massive, coral submassive, coral foliose and coral encrusting). The results confirm that diseased corals most favor to macro-algae growth(15.27%) rather than the sedimentation covered corals(8.24 %). In the degradation of coral life forms, massive corals were more highly damaged(7.05%) than any other forms. Within a short period of time(May to September), coral coverage shrank to 17.4% from 21.9%, macro-algae increased 23.51% and the average sedimentation rate attained 77.52 mg cm^(-2) d^(-1) with persisting coral reef diseases of 17.59%. The Pearson correlation showed that the coral cover decreased with increasing macro-algae growth, which was statistically significant(r =-0.774, n = 100, P < 0.0005). The proliferation of the various macro-algae C. scalpellifrmis, T. ornata, C. racemosa, T. conaides, U. reticulata, S. wightii, K. alvarezii, P. gymnosphora and C. lentillifera increased with percentages of 6.0, 5.8, 5.7, 4.9, 4.2, 3.7, 2.7 and 1.9, respectively. If this trend continues, the next generation of new recruit corals will undoubtedly lead to a phase shift in Gulf of Mannar corals.
文摘Gas hydrates are solid inclusion compounds that are composed of a three-dimensional hydrogen-bonded network of water cages that can trap small gas molecules, such as methane and carbon dioxide. Understanding the rheological properties of gas hydrate crystals in solution can he critical in a number of energy applications, including the transportation of natural gas in suhsea and onshore operations, as well as technological applications for gas separation, desalination, or sequestration. A number of exper- imental and modeling studies have been done on hydrate slurry rheology; however, the link between theory and experiment is not well-defined. This article provides a review on the current state of the art of hydrate slurry viscosity measurements from high- and low-pressure rheometer studies and high-pressure flowloops over a range of different sub-cooling （ATsub = TequiI Texp） and fluid conditions, including for water and oil continuous systems. The theoretical models that have been developed to describe the gas hydrate slurry relative viscosity are also reviewed. Perspectives＇ linkage between the experiments and theory is also discussed.
文摘In her book, The Human Condition, Hannah Arendt states： ＂we are all the same, that is, human, in such a way that nobody is ever the same as anybody else＂ （1998, 8）. In this statement, we are the same （equality） and yet nobody is ever the same as anybody else （plurality）. This may sound contradictory yet what it means is that there is a common base which makes us all the same, and precisely because of this base, we are able to make comparisons and hence differentiate one from the other because we are all different. When analyzing two concepts, an equal status in at least one normatively relevant respect is needed. Where there is one, there is the other precisely because of the other and vice versa. The fact that it is only at least one respect that is needed implies the existence of other aspects that act as common distinguishing factors. Therefore, distinction implies equality. The paper will explore how according to Arendt, equality, a political concept, has been perverted into a social concept. In her view, previously, differing circumstances and conditions served as ＂protection＂ and actually had a protective role. An explanation will thus be given as to how a lack of these differences in the modem period has resulted in a challenge and how this challenge has created unexpected problems for the human condition. This implies reflexivity between political theory and the human agent, and will be presented from Arendt＇s perspective.
基金supported by the National Science Foundation of China under Grant No. 10774131the Foundation of Educational Commission of Zhejiang Province of China under Grant No. 20060191
文摘The entanglement of the generalized two-mode binomial states in the phase damping channel is studied by making use of the relative entropy of the entanglement. It is shown that the factors of q and p play the crucial roles in control the relative entropy of the entanglement. Furthermore, we propose a scheme of teleporting an unknown state via the generalized two-mode binomial states, and calculate the mean fidelity of the scheme.
文摘On the basis of the reaction rules and its influencing factors of sulfur compounds in MIP naphtha, a correlation model for describing the correlation between mass fraction of sulfur in MIP naphtha, mass fraction of sulfur in feedstock and volume fraction of olefin in naphtha was developed and the model＇s parameters were estimated. The residual error distribution and statistical study showed that the developed model was reasonable and reliable and able to predict the mass fraction of sulfur compounds in naphtha. The correlation model can provide theoretical guidance and operation base for adjusting process parameters to produce EURO IV gasoline by the MIP units. The model was validated by its application on the MIP unit of Qingdao Refining ＆ Chemical Company. On this unit, the tail oil with low sulfur content obtained via hydrotreating gas oil was used as the feedstock and the olefin content of naphtha was reduced by promoting hydrogen transfer reaction through adjustment of process parameters. Thus, EURO IV clean gasoline was manufactured by this MIP unit.
文摘The definition and criterion of the Mei symmetry of a relativistic variable mass system are given. The relation between the Mei symmetry and the Noether symmetry of the system is found under infinitesimal transformations of groups. The conserved quantities to which the Mei symmetry and Noether symmetry of the system lead are obtained.An example is given to illustrate the application of the result.
文摘The Jordan＇s NAP （national action plan） provides a set of priority actions for the conservation of marine turtles and their habitats in the Gulf of Aqaba, Red Sea. The main threats to the maintenance of stable turtle populations in Jordan range from opportunistic capture to global threats such fishing mortality and from pollution incidents. Jordan＇s NAP addresses the primary causes of turtle mortality with a series of proposed actions. It includes reducing threats from commercial fisheries, development operations, promoting turtle rescue and rehabilitation along with public awareness activities. It considered also a set of recommendations to reflect the importance of protecting marine turtles in Jordan＇s Gulf of Aqaba. It includes community participation in conservation, capacity of national agencies to carry out management activities and to enforce legislations. To each priority actions identified in NAP, expected results and performance indicators were defined. Hence, the designation of a level of urgency to each specific priority action allowed a phased approach for implementation, subject to budget and available national capacity. Currently, NAP is performing effectively through an integrated network of national working groups including government and non-governmental organisations and other stakeholders.
基金Supported by the National Natural Science Foundation of China under Grant Nos.10775097 and 10874174by the Specialized Research Fund for the for the Doctorial Progress of Higher Education of China under Grant No.20070358009
文摘We introduce a kind of number-conserving coherent state in Rindler space which can describe the quantum state of thermal particles observed in Rindler space. This is based on the Unruh effect that the thermal particles seen by an accelerating observer in fiat space can be seen by an inertial observer in curved space under a conformal transformation.
文摘Quantitative structure-retention relationship （QSRR） model for the estimation of retention indices （RIs） of 39 oxygen-containing compounds containing ketones and esters was established by our newly introduced distance-based atom-type indices DAI. The useful application of the novel DAI indices has been demonstrated by developing accurate predictive equations for gas chromatographic retention indices. The statistical results of the multiple linear regression for the final model are τ=0.9973 and s=8.23. Furthermore, an external test set of 10 oxo-containing compounds can be accurately predicted with the final equation giving the following statistical results： τpred：0.9966 and spred=8.56.
文摘Historic cities are cultural achievements that are gradually created by inhabitants over the centuries. In developed countries, the conservation of historic cities seems to be generally acknowledged as a method of community development that does not depend on huge exploitation. On the other hand, no sufficient countermeasures have been taken in developing countries because most native stakeholders are still interested in development. Here the author could focus on so-called ＂international cooperation＂, but urban conservation for historic cities where inhabitants actually live is still a minor consideration except for some government-based conservation projects for monuments and isolated examples of cultural heritage. In this paper, the example was taken of a conservation project which has been carried out by JICA （Japanese International Cooperation Agency） in Damascus, the old capital of Syria. The target area for the project is ＂Qanawat South＂. Although the origin of＂Qanawat South＂ dates back to the Roman age, efforts for urban conservation have not been well organized, partly because the area is located outside of the so-called old city registered as a world heritage site. For example, the master plan of 1968 indicated the redistribution of the traditional quarters, while some conservation laws have been restricting the regeneration of the area. Moreover, there is not yet any consensus among the stakeholders concerning the historical value of the quarter, they are still questioning why the area should be conserved rather than being freely sold or developed and what and how they should contribute to conservation. Based on analysis of the actual situation of Qasr al-Hajjaj Street, this paper examines a method called ＂restoration-type＂ facade improvement adopted by JICA, for which the final goal is not only to maintain the appearance of the street but also to activate the life of the habitants of the street.
文摘The operating mechanism refers to the structural setup, component assembly and inspection maintenance of the safeguards and its efficient operation. Health insurance management mechanism refers to the effective combination, governance, operation, evaluation and improvement of medical service stakeholders. It is a series of institutional arrangements to effectively provide medical services and safeguard the interests of beneficiaries.＂
