To design an efficient protocol for sharing the encrypted lock keys in the renting house system,we introduce a new notion called time-and identitybased proxy reencryption(TIPRE)and the blockchain platform.Our CPA secu...To design an efficient protocol for sharing the encrypted lock keys in the renting house system,we introduce a new notion called time-and identitybased proxy reencryption(TIPRE)and the blockchain platform.Our CPA secure TIPRE scheme is constructed from Green et al.’s identity-based proxy reencryption scheme by adding the time property.In every time period,a time stamp authority generates a public key embedded with the current time stamp for each user.In our protocol for the renting house system,the TIPRE scheme is the primary building block,and the blockchain platform serves instead of a trusted third party,such as a real estate agency between landlords and tenants.The TIPRE scheme allows the landlord to change the lock key at each time period for safety.The blockchain platform allows the landlords and tenants to directly interact,and all of the interactions are recorded in the blockchain database to provide the desired security requirements,such as nonrepudiation and unforgeability.Finally,we provide the secure analysis of our protocol and test its performance by implementing it in the MacBook Pro and the Intel Edison development platforms.展开更多
This study updates the source of innovation theories by investigating the relationship between demand-and supply-driven innovation through a study of a fresh Chinese case of Alipay credit renting platform.Based on the...This study updates the source of innovation theories by investigating the relationship between demand-and supply-driven innovation through a study of a fresh Chinese case of Alipay credit renting platform.Based on the primary data collected via interview and focus group discussion,as well as the secondary data from the company’s website and media report,three main findings were obtained.First of all,from this case,we identify an unseparated relationship between demand-and supply-driven innovation and problems arose when one side is isolated and not given full attention.This adds new insights to the research on the source of innovation.Secondly,we propose that blue ocean strategical framework can help connect the demand side with the supply sides and facilitate the innovation.This provides some managerial guidelines to deal with the challenges as observed in this case.Lastly,this paper analyzes this new renting model(Alipay credit renting platform)from both lessors and lessees’perspectives,representing the first study to investigate the credit renting market systematically.展开更多
The house rental issue is one of the elemental parts of society. Nowadays, it is extremely difficult to find suitable accommodation in city areas if people search for it physically. On the other hand, the land owner a...The house rental issue is one of the elemental parts of society. Nowadays, it is extremely difficult to find suitable accommodation in city areas if people search for it physically. On the other hand, the land owner also needs to rent the house. It can be difficult to find tenants just to hang a lease sign on a building, and as a result, they lose money. An online common platform can play a vital role in this case. The purpose of the study is to develop a common web-based online platform for both tenants and house owners so that both tenants and landowners will mutually benefit from the system. This paper presents the development of web applications for the people of Bangladesh where both house owners and tenants can register and tenants can have houses for rent via sophisticated contact with the house owner. In this paper, a common online-based smart house rental web application has been developed both for tenants and for house owners. This web application is very user-friendly, efficient and it has got many unique features that are not offered by other currently available house rental websites here in Bangladesh. Tenants can register using their phone number, store information about their identity, search for available houses, send messages to house owners, and choose a suitable house using developed web applications. House owners can also register for the system, which will manually verify and authenticate the knowledge provided by the house owner can view a tenant’s information history whenever a tenant makes contact through text and supply house-related information accordingly. The proposed online smart house system has been tested and validated. It works very efficiently with many features. The application provided faster and improved opportunities to get houses, as well as ensuring the availability of houses for rent in the greatest number of areas. The system will help to spread trustworthy services nationwide and supply users with the chance to speak and improve the house rent in Bangladesh. Because it has many smart features, this developed online smart house rental web application will make it very easy for tenants to find a house to rent. House owners, on the other hand, can easily rent out their properties.展开更多
The governance of state-owned enterprises(SOEs)has long been central to political and institutional economic debates.Critics often associate SOEs with ine"ciency,rent-seeking and dogma,treating them as relics of ...The governance of state-owned enterprises(SOEs)has long been central to political and institutional economic debates.Critics often associate SOEs with ine"ciency,rent-seeking and dogma,treating them as relics of command economies.Yet in many developmental states,they have been engines of industrialisation,technological progress and national resilience.China provides perhaps the most striking example.Its SOEs have survived and evolved,some becoming globally competitive multinationals in energy,infrastructure and telecommunications.展开更多
For the longest time,New York's Upper Fifth Avenue held the title of“the most expensive street in the world”,but it has recently been overtaken by Montenapoleone,an upscale shopping street in Milan,Italy.Every y...For the longest time,New York's Upper Fifth Avenue held the title of“the most expensive street in the world”,but it has recently been overtaken by Montenapoleone,an upscale shopping street in Milan,Italy.Every year,America publishes a global index(指数)that ranks the world's most expensive shopping areas by the rent prices they command.Fifth Avenue has been ranking first out of 138 leading retail destinations around the world for many years,but last year,it was surpassed by Montenapoleone,the most popular luxury shopping street in Milan.Not only is this short street a magnet(有吸引力的事物)for tourists interested only in window⁃shopping,but it also attracts some of the wealthiest people around the globe,many of who spend at least$2,600 per purchase,the highest average receipt in the world.展开更多
In the contemporary global landscape,understanding the nexus between financial inclusion and natural resource abundance is crucial,especially for resource-rich nations.This study uses diagnostic tests and method of mo...In the contemporary global landscape,understanding the nexus between financial inclusion and natural resource abundance is crucial,especially for resource-rich nations.This study uses diagnostic tests and method of moments quantile regression to examines this interplay across Australia,Brazil,Canada,China,India,Russia,and the United States.We find that achieving financial inclusion is significantly challenging for countries that heavily rely on natural resources.Diversified income sources and equitable wealth distribution are essential to mitigate these challenges.Additionally,we identify a positive correlation between economic development and financial inclusion,highlighting the mutually reinforcing relationship between growth and inclusivity.Our research also reveals a notable link between adopting renewable energy and improving financial inclusion,suggesting that environmental responsibility and financial accessibility are intertwined.Foreign direct investment has nuanced impacts on financial inclusion,adding depth to our understanding.Overall,stable income from natural resources and diversified economic development emerge as key promoters of financial inclusion.These insights advocate for regionally specific policies and lay a solid foundation for future research and informed policymaking that address financial inclusion challenges and advance sustainable development.展开更多
The inner-urban residential location choice is a topic of continuing interest in urban geography.However,not much research has been done on migrants’rental location choices.Based on data from a questionnaire complete...The inner-urban residential location choice is a topic of continuing interest in urban geography.However,not much research has been done on migrants’rental location choices.Based on data from a questionnaire completed by 276 migrant renters in Guangzhou,this paper analyzes the demographics and social class characteristics of migrants,and the condition and location of housing preferred by this population.The results show that the migrants in Guangzhou mainly rent in the Center Business District(CBD)area(Tianhe District)and Huangpu,Panyu and Haizhu districts.The main reason for this choice of location choices is the houses’convenience to their workplaces.A second reason is that nearby subways make travel convenient,for consumption and daily life,for children to go to school,and for access to large shopping centers/malls.展开更多
The laser-induced fluorescence excitation spectra of jet-cooled NiB radicals have been recorded in the energy range of 19000-22100 cm-1. Eleven bands have been assigned to the [20.77]2П-X2∑＋ transition system for t...The laser-induced fluorescence excitation spectra of jet-cooled NiB radicals have been recorded in the energy range of 19000-22100 cm-1. Eleven bands have been assigned to the [20.77]2П-X2∑＋ transition system for the first time. The dispersed fluorescence spectra related to most of these bands have been investigated. Vibrationally excited levels of the ground electronic state, with v＂ up to 6, have been observed. In addition, the lifetimes for almost all the observed bands have also been measured.展开更多
Based on the 2-D flow and sediment numerical model of the Yangtze Estuary and the Hangzhou Bay, the characteristics of water and sediment exchange in their joint waters is studied through quantitative calculation and ...Based on the 2-D flow and sediment numerical model of the Yangtze Estuary and the Hangzhou Bay, the characteristics of water and sediment exchange in their joint waters is studied through quantitative calculation and analysis of the characteristics of water flow and sediment transportation. The results show that there is periodical water and sediment exchange in this joint waters, that the net water exchange appears mainly between 0 - 6 m depth （theoretical datum plane, the same below） offshore and the maximum is near the depth of 2 m, and that the net sediment exchange mainly appears between 0 - 5 m depth and the maximum is near the depth of 3 m, indicating that the range of water flow passage is different from that of sediment transport from the Yangtze Estuary to the Hangzhou Bay. Combined with the results of numerical simulation, this paper also analyzes the hydrodynamical mechanism influencing water and sediment exchange between the Yangtze Estuary and the Hangzhou Bay, including tidal fluctuation, tidal current kinetic energy, tide-induced residual current and the trace of water particles. Finally, the sediment transportation passage on the Nanhui tidal fiat is discussed, and the results show that sediment is transported into the Hangzhou Bay from the south side of Shipilei, while sediment is brought back to the South Channel of the Yangtze Estuary from the north side.展开更多
Ecological land rent is the excess profit produced by resource scarcity, and is also an important indicator for measuring the social and economic effects of resource scarcity. This paper, by calculating the respective...Ecological land rent is the excess profit produced by resource scarcity, and is also an important indicator for measuring the social and economic effects of resource scarcity. This paper, by calculating the respective ecological land rents of all the provinces in China for the years 2002 and 2007, and with the assistance of the software programs ArcGIS and GeoDA, analyzes the spatial differentiation characteristics of ecological land rent; then, the influencing factors of ecological land rent differentiation among the provinces are examined using the methods of traditional regression and spatial correlation analysis. The following results were obtained： First, ecological land rent per unit of output in China shows stable dis- tribution characteristics of being low in the southwestern and northeastern provinces, and high in Hebei and Henan provinces. There is also an increasing tendency in the central and western provinces, and a decreasing one in the eastern provinces. In general, the spatial distribution of ecological land rent per unit of output in China is quite scattered. Second, the total ecological land rent shows significant spatial aggregation characteristics, in particular the provinces in China possessing high total amounts of ecological land rent tend to be adjacent to one another, as do those with low total amounts, and the spatial difference characteristics of the eastern, central and western provinces are distinguished. The Bohai Rim, Yangtze River Delta and Pearl River Delta are shown to be highly clustering regions of total ecological land rent, while the western provinces have very low ecological land rent in terms of total amount. Third, population distribution, economic level and industrial structure were all im- portant influencing factors influencing ecological land rent differentiation among provinces in China. Furthermore, population density, urbanization level, economic density, per capita consumption level and GDP per capita were all shown to be positively related to total eco- logical land rent, which indicates that spatial clustering exists between ecological land rent and these factors. However, there was also a negative correlation between ecological land rent and agricultural output percentage, indicating that spatial scattering exists between ecological land rent and agricultural output percentage.展开更多
In this paper,transient electromagnetic method was used to carry out the feasibility study on the detection and recognition of chamber blasting misfire.Firstly,an electromagnetic background field was established in th...In this paper,transient electromagnetic method was used to carry out the feasibility study on the detection and recognition of chamber blasting misfire.Firstly,an electromagnetic background field was established in the test;secondly,a benign conductor was preset in the chamber,and then the background field was eliminated after the electromagnetic field was measured;thirdly,the transient electromagnetic field was measured again after blasting;at last,the chamber blasting misfire was detected and recognized by comparing the change of eddy current field of the preset benign conductor before and after blasting.The test results showed that:When the buried depth of aluminum box target was no more than 30 m,transient electromagnetic method can clearly identify the position of the aluminum box;when the buried depth of aluminum box was more than30 m,the buried depth and position of the aluminum box was not sure due to the unknown level of secondary eddy current field generated by aluminum box.展开更多
In spite of a steady improvement in the safety of cataract surgery since the inception of phacoemulsification, diagnosing and managing posterior capsular rent still remains a challenge. Identification of the pre-exist...In spite of a steady improvement in the safety of cataract surgery since the inception of phacoemulsification, diagnosing and managing posterior capsular rent still remains a challenge. Identification of the pre-existing risk factors is of utmost importance so that precautionary modifications are done in the surgery to prevent this complication. Once it happens, timely realization and appropriate management can have excellent outcomes.展开更多
Motion state of ship out of control in bridge area was analyzed.Motion procedure after losing control was divided into two steps.One is drift step within stopping period.The other is drift step without inertia,which i...Motion state of ship out of control in bridge area was analyzed.Motion procedure after losing control was divided into two steps.One is drift step within stopping period.The other is drift step without inertia,which is induced by wind and current.Mathematical model for motion of ship out of control,considering wind-induced drift,current-induced drift,stopping ability,etc.,was established.Dangerous collision areas for main pier and auxiliary piers were analyzed according to different calculation conditions.展开更多
The focus of land economics is on how to decrease the misallocation of resources to achieve an optimal allocation of resources. Both the theories of new economics of labor migration(NELM) and the conclusions of empiri...The focus of land economics is on how to decrease the misallocation of resources to achieve an optimal allocation of resources. Both the theories of new economics of labor migration(NELM) and the conclusions of empirical studies reveal that land resources will inevitably be reallocated(e.g., rented out) if the resources of family labor are reallocated(e.g., off-farm employment). However, this study reveals that off-farm employment does not inevitably lead to land rent out. More precisely, this study uses survey data on 8031 peasant households from 27 provinces in China and explores the relationship between off-farm employment and land rent out by describing spatial features and through empirical analysis(e.g., IV-Probit model and IV-Tobit model). The results show the following: 1) There is an indirect relationship between off-farm employment and land rent out regarding spatial area aggregation, i.e., regions with a higher ratio of off-farm employment also have a lower area of land rent out. 2) Off-farm employment is significantly positively correlated with the behavior of land rent out, but its square is significantly negatively correlated with the behavior, i.e., there is an inverted U-shaped relationship between off-farm employment and the behavior of land rent out, with the turning point being 55.55% offfarm employment. 3) Off-farm employment is significantly positively correlated with the area of land rent out, but its square is significantly negatively correlated with the area, i.e., there is an inverted Ushaped relationship between off-farm employment and the area of land rent out, with the turning point being 56.22% off-farm employment. This study helps explain why China has a high ratio of off-farm employment but a lower rate of land rent out.展开更多
At present, paid urban landuse system is one of the most important economic reform in China. In the other words, landuse right can be transferred and land users must pay the rent to the state according to the quality ...At present, paid urban landuse system is one of the most important economic reform in China. In the other words, landuse right can be transferred and land users must pay the rent to the state according to the quality of land. It is necessary toapply the theory of rent and location to the economic appraisal of urban land. China is vast in territory. Is's geographical condition and economic development vary from place to place, so does the urban land value. In order to reveal the difference of land value between different cities, the following method is used. (1) Analysing the factors and elements that affect the quality of urban land. Six factors including 17 elements were selected in this paper: macrolocation of a city, benefit of urban aggregation, infrastructure investment, output value of urban land, potential of urban land, and investment intensity. (2) Deciding the weight andvalue of each factor. (3) Appraising each element separately. (4) Accountingthe value of all factors and getting the total appraisal score of each city. (5) Grouping the 430 Chinese cities into sevencategories according to the appraisal values.The result shows that all the cities in the category with the highest land output values are in the coast belt, whereas most cities in the inland and outlying areas are belong to the category with low rank. For example, 87% of the cities in the outlying regions are belong to the lowest rank. Although there are some relationship between the size of cities and urban land rank, generally speaking, the larger the city, the higher the urban land rank. In fact, the locational condition is the most important factor which influences the rank of urban land.展开更多
基金This research is partially supported by the National Natural Science Foundation of China under Grant Nos.61672016the Jiangsu Qing Lan Project,the Six Talent Peaks Project in Jiangsu Province under Grant RJFW-010the Guangxi Key Laboratory of Cryptography and Information Security under Grant GCIS201815.
文摘To design an efficient protocol for sharing the encrypted lock keys in the renting house system,we introduce a new notion called time-and identitybased proxy reencryption(TIPRE)and the blockchain platform.Our CPA secure TIPRE scheme is constructed from Green et al.’s identity-based proxy reencryption scheme by adding the time property.In every time period,a time stamp authority generates a public key embedded with the current time stamp for each user.In our protocol for the renting house system,the TIPRE scheme is the primary building block,and the blockchain platform serves instead of a trusted third party,such as a real estate agency between landlords and tenants.The TIPRE scheme allows the landlord to change the lock key at each time period for safety.The blockchain platform allows the landlords and tenants to directly interact,and all of the interactions are recorded in the blockchain database to provide the desired security requirements,such as nonrepudiation and unforgeability.Finally,we provide the secure analysis of our protocol and test its performance by implementing it in the MacBook Pro and the Intel Edison development platforms.
文摘This study updates the source of innovation theories by investigating the relationship between demand-and supply-driven innovation through a study of a fresh Chinese case of Alipay credit renting platform.Based on the primary data collected via interview and focus group discussion,as well as the secondary data from the company’s website and media report,three main findings were obtained.First of all,from this case,we identify an unseparated relationship between demand-and supply-driven innovation and problems arose when one side is isolated and not given full attention.This adds new insights to the research on the source of innovation.Secondly,we propose that blue ocean strategical framework can help connect the demand side with the supply sides and facilitate the innovation.This provides some managerial guidelines to deal with the challenges as observed in this case.Lastly,this paper analyzes this new renting model(Alipay credit renting platform)from both lessors and lessees’perspectives,representing the first study to investigate the credit renting market systematically.
文摘The house rental issue is one of the elemental parts of society. Nowadays, it is extremely difficult to find suitable accommodation in city areas if people search for it physically. On the other hand, the land owner also needs to rent the house. It can be difficult to find tenants just to hang a lease sign on a building, and as a result, they lose money. An online common platform can play a vital role in this case. The purpose of the study is to develop a common web-based online platform for both tenants and house owners so that both tenants and landowners will mutually benefit from the system. This paper presents the development of web applications for the people of Bangladesh where both house owners and tenants can register and tenants can have houses for rent via sophisticated contact with the house owner. In this paper, a common online-based smart house rental web application has been developed both for tenants and for house owners. This web application is very user-friendly, efficient and it has got many unique features that are not offered by other currently available house rental websites here in Bangladesh. Tenants can register using their phone number, store information about their identity, search for available houses, send messages to house owners, and choose a suitable house using developed web applications. House owners can also register for the system, which will manually verify and authenticate the knowledge provided by the house owner can view a tenant’s information history whenever a tenant makes contact through text and supply house-related information accordingly. The proposed online smart house system has been tested and validated. It works very efficiently with many features. The application provided faster and improved opportunities to get houses, as well as ensuring the availability of houses for rent in the greatest number of areas. The system will help to spread trustworthy services nationwide and supply users with the chance to speak and improve the house rent in Bangladesh. Because it has many smart features, this developed online smart house rental web application will make it very easy for tenants to find a house to rent. House owners, on the other hand, can easily rent out their properties.
文摘The governance of state-owned enterprises(SOEs)has long been central to political and institutional economic debates.Critics often associate SOEs with ine"ciency,rent-seeking and dogma,treating them as relics of command economies.Yet in many developmental states,they have been engines of industrialisation,technological progress and national resilience.China provides perhaps the most striking example.Its SOEs have survived and evolved,some becoming globally competitive multinationals in energy,infrastructure and telecommunications.
文摘For the longest time,New York's Upper Fifth Avenue held the title of“the most expensive street in the world”,but it has recently been overtaken by Montenapoleone,an upscale shopping street in Milan,Italy.Every year,America publishes a global index(指数)that ranks the world's most expensive shopping areas by the rent prices they command.Fifth Avenue has been ranking first out of 138 leading retail destinations around the world for many years,but last year,it was surpassed by Montenapoleone,the most popular luxury shopping street in Milan.Not only is this short street a magnet(有吸引力的事物)for tourists interested only in window⁃shopping,but it also attracts some of the wealthiest people around the globe,many of who spend at least$2,600 per purchase,the highest average receipt in the world.
基金supported by the grant from National Social Science Fund of China(23BJY085).
文摘In the contemporary global landscape,understanding the nexus between financial inclusion and natural resource abundance is crucial,especially for resource-rich nations.This study uses diagnostic tests and method of moments quantile regression to examines this interplay across Australia,Brazil,Canada,China,India,Russia,and the United States.We find that achieving financial inclusion is significantly challenging for countries that heavily rely on natural resources.Diversified income sources and equitable wealth distribution are essential to mitigate these challenges.Additionally,we identify a positive correlation between economic development and financial inclusion,highlighting the mutually reinforcing relationship between growth and inclusivity.Our research also reveals a notable link between adopting renewable energy and improving financial inclusion,suggesting that environmental responsibility and financial accessibility are intertwined.Foreign direct investment has nuanced impacts on financial inclusion,adding depth to our understanding.Overall,stable income from natural resources and diversified economic development emerge as key promoters of financial inclusion.These insights advocate for regionally specific policies and lay a solid foundation for future research and informed policymaking that address financial inclusion challenges and advance sustainable development.
基金funded by the National Natural Science Foundation of China(No.41871150,No.42001130)GDAS Special Project of Science and Technology Development(No.2020GDASYL-20200104001)+1 种基金National Key Research and Development Program(No.2019YFB2103101)Special Project of the Institute of Strategy Research for Guangdong,Hong Kong,and Macao Greater Bay Area Construction(No.2021GDASYL-20210401001).
文摘The inner-urban residential location choice is a topic of continuing interest in urban geography.However,not much research has been done on migrants’rental location choices.Based on data from a questionnaire completed by 276 migrant renters in Guangzhou,this paper analyzes the demographics and social class characteristics of migrants,and the condition and location of housing preferred by this population.The results show that the migrants in Guangzhou mainly rent in the Center Business District(CBD)area(Tianhe District)and Huangpu,Panyu and Haizhu districts.The main reason for this choice of location choices is the houses’convenience to their workplaces.A second reason is that nearby subways make travel convenient,for consumption and daily life,for children to go to school,and for access to large shopping centers/malls.
文摘The laser-induced fluorescence excitation spectra of jet-cooled NiB radicals have been recorded in the energy range of 19000-22100 cm-1. Eleven bands have been assigned to the [20.77]2П-X2∑＋ transition system for the first time. The dispersed fluorescence spectra related to most of these bands have been investigated. Vibrationally excited levels of the ground electronic state, with v＂ up to 6, have been observed. In addition, the lifetimes for almost all the observed bands have also been measured.
基金This study was supported bythe National Natural Science Foundation of China (Grant Nos 40476039 and 50339010)
文摘Based on the 2-D flow and sediment numerical model of the Yangtze Estuary and the Hangzhou Bay, the characteristics of water and sediment exchange in their joint waters is studied through quantitative calculation and analysis of the characteristics of water flow and sediment transportation. The results show that there is periodical water and sediment exchange in this joint waters, that the net water exchange appears mainly between 0 - 6 m depth （theoretical datum plane, the same below） offshore and the maximum is near the depth of 2 m, and that the net sediment exchange mainly appears between 0 - 5 m depth and the maximum is near the depth of 3 m, indicating that the range of water flow passage is different from that of sediment transport from the Yangtze Estuary to the Hangzhou Bay. Combined with the results of numerical simulation, this paper also analyzes the hydrodynamical mechanism influencing water and sediment exchange between the Yangtze Estuary and the Hangzhou Bay, including tidal fluctuation, tidal current kinetic energy, tide-induced residual current and the trace of water particles. Finally, the sediment transportation passage on the Nanhui tidal fiat is discussed, and the results show that sediment is transported into the Hangzhou Bay from the south side of Shipilei, while sediment is brought back to the South Channel of the Yangtze Estuary from the north side.
基金National Natural Science Foundation of China, No.41001382 No.41201386
文摘Ecological land rent is the excess profit produced by resource scarcity, and is also an important indicator for measuring the social and economic effects of resource scarcity. This paper, by calculating the respective ecological land rents of all the provinces in China for the years 2002 and 2007, and with the assistance of the software programs ArcGIS and GeoDA, analyzes the spatial differentiation characteristics of ecological land rent; then, the influencing factors of ecological land rent differentiation among the provinces are examined using the methods of traditional regression and spatial correlation analysis. The following results were obtained： First, ecological land rent per unit of output in China shows stable dis- tribution characteristics of being low in the southwestern and northeastern provinces, and high in Hebei and Henan provinces. There is also an increasing tendency in the central and western provinces, and a decreasing one in the eastern provinces. In general, the spatial distribution of ecological land rent per unit of output in China is quite scattered. Second, the total ecological land rent shows significant spatial aggregation characteristics, in particular the provinces in China possessing high total amounts of ecological land rent tend to be adjacent to one another, as do those with low total amounts, and the spatial difference characteristics of the eastern, central and western provinces are distinguished. The Bohai Rim, Yangtze River Delta and Pearl River Delta are shown to be highly clustering regions of total ecological land rent, while the western provinces have very low ecological land rent in terms of total amount. Third, population distribution, economic level and industrial structure were all im- portant influencing factors influencing ecological land rent differentiation among provinces in China. Furthermore, population density, urbanization level, economic density, per capita consumption level and GDP per capita were all shown to be positively related to total eco- logical land rent, which indicates that spatial clustering exists between ecological land rent and these factors. However, there was also a negative correlation between ecological land rent and agricultural output percentage, indicating that spatial scattering exists between ecological land rent and agricultural output percentage.
文摘In this paper,transient electromagnetic method was used to carry out the feasibility study on the detection and recognition of chamber blasting misfire.Firstly,an electromagnetic background field was established in the test;secondly,a benign conductor was preset in the chamber,and then the background field was eliminated after the electromagnetic field was measured;thirdly,the transient electromagnetic field was measured again after blasting;at last,the chamber blasting misfire was detected and recognized by comparing the change of eddy current field of the preset benign conductor before and after blasting.The test results showed that:When the buried depth of aluminum box target was no more than 30 m,transient electromagnetic method can clearly identify the position of the aluminum box;when the buried depth of aluminum box was more than30 m,the buried depth and position of the aluminum box was not sure due to the unknown level of secondary eddy current field generated by aluminum box.
文摘In spite of a steady improvement in the safety of cataract surgery since the inception of phacoemulsification, diagnosing and managing posterior capsular rent still remains a challenge. Identification of the pre-existing risk factors is of utmost importance so that precautionary modifications are done in the surgery to prevent this complication. Once it happens, timely realization and appropriate management can have excellent outcomes.
基金Supported by Disaster Reduction Foundation of Large Complex Project for Sutong Bridge(No.2006BAG04B06)
文摘Motion state of ship out of control in bridge area was analyzed.Motion procedure after losing control was divided into two steps.One is drift step within stopping period.The other is drift step without inertia,which is induced by wind and current.Mathematical model for motion of ship out of control,considering wind-induced drift,current-induced drift,stopping ability,etc.,was established.Dangerous collision areas for main pier and auxiliary piers were analyzed according to different calculation conditions.
基金financial support from the National Social Science Foundation of China (Grant No. 14XGL003)the National Natural Science Foundation of China (Grant No. 41801221)
文摘The focus of land economics is on how to decrease the misallocation of resources to achieve an optimal allocation of resources. Both the theories of new economics of labor migration(NELM) and the conclusions of empirical studies reveal that land resources will inevitably be reallocated(e.g., rented out) if the resources of family labor are reallocated(e.g., off-farm employment). However, this study reveals that off-farm employment does not inevitably lead to land rent out. More precisely, this study uses survey data on 8031 peasant households from 27 provinces in China and explores the relationship between off-farm employment and land rent out by describing spatial features and through empirical analysis(e.g., IV-Probit model and IV-Tobit model). The results show the following: 1) There is an indirect relationship between off-farm employment and land rent out regarding spatial area aggregation, i.e., regions with a higher ratio of off-farm employment also have a lower area of land rent out. 2) Off-farm employment is significantly positively correlated with the behavior of land rent out, but its square is significantly negatively correlated with the behavior, i.e., there is an inverted U-shaped relationship between off-farm employment and the behavior of land rent out, with the turning point being 55.55% offfarm employment. 3) Off-farm employment is significantly positively correlated with the area of land rent out, but its square is significantly negatively correlated with the area, i.e., there is an inverted Ushaped relationship between off-farm employment and the area of land rent out, with the turning point being 56.22% off-farm employment. This study helps explain why China has a high ratio of off-farm employment but a lower rate of land rent out.
文摘At present, paid urban landuse system is one of the most important economic reform in China. In the other words, landuse right can be transferred and land users must pay the rent to the state according to the quality of land. It is necessary toapply the theory of rent and location to the economic appraisal of urban land. China is vast in territory. Is's geographical condition and economic development vary from place to place, so does the urban land value. In order to reveal the difference of land value between different cities, the following method is used. (1) Analysing the factors and elements that affect the quality of urban land. Six factors including 17 elements were selected in this paper: macrolocation of a city, benefit of urban aggregation, infrastructure investment, output value of urban land, potential of urban land, and investment intensity. (2) Deciding the weight andvalue of each factor. (3) Appraising each element separately. (4) Accountingthe value of all factors and getting the total appraisal score of each city. (5) Grouping the 430 Chinese cities into sevencategories according to the appraisal values.The result shows that all the cities in the category with the highest land output values are in the coast belt, whereas most cities in the inland and outlying areas are belong to the category with low rank. For example, 87% of the cities in the outlying regions are belong to the lowest rank. Although there are some relationship between the size of cities and urban land rank, generally speaking, the larger the city, the higher the urban land rank. In fact, the locational condition is the most important factor which influences the rank of urban land.
