Analyzing agricultural sustainability is essential for designing and assessing rural development initiatives.However,accurately measuring agricultural sustainability is complicated since it involves so many different ...Analyzing agricultural sustainability is essential for designing and assessing rural development initiatives.However,accurately measuring agricultural sustainability is complicated since it involves so many different factors.This study provides a new suite of quantitative indicators for assessing agricultural sustainability at regional and district levels,involving environmental sustainability,social security,and economic security.Combining the PressureState-Response(PSR)model and indicator approach,this study creates a composite agricultural sustainability index for the 14 mainstream agro-climatic regions of India.The results of this study show that the Trans-Gengatic Plain Region(TGPR)ranks first in agricultural sustainability among India's 14 mainstream agro-climatic regions,while the Eastern Himalayan Region(EHR)ranks last.Higher livestock ownership,cropping intensity,per capita income,irrigation intensity,share of institutional credit,food grain productivity,crop diversification,awareness of minimum support price,knowledge sharing with fellow farmers,and young and working population,as well as better transportation facilities and membership of agricultural credit societies are influencing indicators responsible for higher agricultural sustainability in TGPR compared with EHR.Although,the scores of environmental sustainability indicators of EHR are quite good,its scores of social and economic security indicators are fairly low,putting it at the bottom of the rank of agricultural sustainability index among the 14 mainstream agroclimatic regions in India.This demonstrates the need of understanding agricultural sustainability in relation to social and economic dimensions.In a nation as diverse and complicated as India,it is the social structure that determines the health of the economy and environment.Last but not least,the sustainability assessment methodology may be used in a variety of India's agro-climatic regions.展开更多
As one of the Special Economic Zones since the reform and opening up, Zhuhai has developed during the past 30 years. Its economic development, industrial structure and ecological environment have undergone great chang...As one of the Special Economic Zones since the reform and opening up, Zhuhai has developed during the past 30 years. Its economic development, industrial structure and ecological environment have undergone great changes. Research on changes in Zhuhai’s land ecological security is of great significance. Using relevant data from 2007-2012, this study established a land ecological security assessment system based on the PSR conceptual framework model. The system contained 18 indicators from 3 aspects according to the concrete features of Zhuhai. Then we used the matterelement analysis and the improved entropy weight to analyze and evaluate the land ecological security of Zhuhai. The results showed that: from 2007 to 2012, the levels of the land ecological security of Zhuhai were “secure”, and the value increased year by year;as the land ecological security response value increased, Zhuhai was capable of solving land ecosystem problems. However, it should be noted that the structure of land ecosystem in Zhuhai has not formed and that rapid expansion of construction land has caused the shortage of cultivated land and other issues. Measures should be taken to control the construction area, improve land intensive utilization and improve the land ecological security.展开更多
We have conducted a comprehensive investigation into the bright single pulse emission from PSR B1133+16using the Giant Metrewave Radio Telescope.High time resolution data(61μs)were obtained at a center frequency of 3...We have conducted a comprehensive investigation into the bright single pulse emission from PSR B1133+16using the Giant Metrewave Radio Telescope.High time resolution data(61μs)were obtained at a center frequency of 322 MHz with a bandwidth of 32 MHz over a continuous observation period of 7.45 hr.A total of 1082 bright pulses were sporadically detected with peak flux densities ranging from 10 to 23 times stronger than the average pulse profile.However,no giant pulse-like emission with a relative pulse energy larger than 10 and extremely short duration was detected,indicating that these bright pulses cannot be categorized as giant pulse emission.The majority of these bright pulses are concentrated in pulse phases at both the leading and trailing windows of the average pulse profile,with an occurrence ratio of approximately 2.74.The pulse energy distribution for all individual pulses can be described by a combination of two Gaussian components and a cutoff power-law with an index of α=-3.2.An updated nulling fraction of 15.35%±0.45% was determined from the energy distribution.The emission of individual pulses follows a log-normal distribution in peak flux density ratio.It is imperative that regular phase drifting in bright pulse sequence is identified in both the leading and trailing components for the first time.Possible physical mechanisms are discussed in detail to provide insights into these observations.展开更多
Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more an...Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more and more attention of the researchers.Aiming at evaluating its ecological and economic system health,a multi-objective evaluation framework called PressureState-Response(PSR) was established to describe the ecological and economic health situations.Meanwhile,an integrative set pair model combining set pair analysis(SPA) and fuzzy analytic hierarchy process(FAHP) was proposed to assess the ecological and economic system.Then the EES status of five northwest provinces(Shanxi,Gansu,Qinghai,Ningxia and Xinjiang) of Northwest region in China was evaluated during 1985 to 2009.The EES development trends of five provinces are obtained.In general,the health values of five provinces showed a rising trend.The health values of five provinces grew rapidly during 1985 to 2000.After 2000,the health values of five provinces still followed the present growth trend,but the growth is relatively smooth.The results show that the method proposed is effective for assessing the health of ecological and economic system.展开更多
We analyzed the spectral properties and pulse profile of PSR J1811-1925,a pulsar located in the center of composite supernova remnant(SNR)G11.2-0.3,by using high timing resolution archival data from the Nuclear Spectr...We analyzed the spectral properties and pulse profile of PSR J1811-1925,a pulsar located in the center of composite supernova remnant(SNR)G11.2-0.3,by using high timing resolution archival data from the Nuclear Spectroscopic Telescope Array Mission(NuSTAR).Analysis of archival Chandra data over different regions rules out the SNR shell as the site of the hard X-ray emission while spectral analysis indicates that the NuSTAR photons originate in the pulsar and its nebula.The pulse profile exhibits a broad single peak up to 35 keV.The jointed spectrum by combining NuSTAR and Chandra can be well fitted by a power-law model with a photon index ofΓ=1.58±0.04.The integrated flux of jointed spectrum over 1-10 keV is 3.36×10^(-12)erg cm^(-2)s^(-1).The spectrum of pulsar having photon indexΓ=1.33±0.06 and a 1-10 keV flux of 0.91×10^(-12)erg cm^(-2)s^(-1).We also performed the phase-resolved spectral analysis by splitting the whole pulse-on phase into five phase bins.The photon indices of the bins are all around 1.4,indicating that the photon index does not evolve with the phase.展开更多
从城市土地利用中的人地关系分析入手,阐述了城市土地集约利用的 PSR 概念系统,并据此构建了评价指标体系,然后采用主成分分析法,从区域空间的角度对浙江省11个地级市的城市土地集约利用情况进行了测度和评价。结果表明:①浙江省东北部...从城市土地利用中的人地关系分析入手,阐述了城市土地集约利用的 PSR 概念系统,并据此构建了评价指标体系,然后采用主成分分析法,从区域空间的角度对浙江省11个地级市的城市土地集约利用情况进行了测度和评价。结果表明:①浙江省东北部地区城市土地集约利用效益较高,西南部偏低,这主要是由于区位优势和产业结构的差异所致;②通过相关分析,发现浙江省城市土地集约利用水平与其 PSR 系统的协调度成正相关。这说明 PSR 各子系统及其内部各因子之间的协调性很大程度上可以反映城市土地集约利用的均衡度,模型可信度比较高,可供有关方面参考借鉴。展开更多
文摘Analyzing agricultural sustainability is essential for designing and assessing rural development initiatives.However,accurately measuring agricultural sustainability is complicated since it involves so many different factors.This study provides a new suite of quantitative indicators for assessing agricultural sustainability at regional and district levels,involving environmental sustainability,social security,and economic security.Combining the PressureState-Response(PSR)model and indicator approach,this study creates a composite agricultural sustainability index for the 14 mainstream agro-climatic regions of India.The results of this study show that the Trans-Gengatic Plain Region(TGPR)ranks first in agricultural sustainability among India's 14 mainstream agro-climatic regions,while the Eastern Himalayan Region(EHR)ranks last.Higher livestock ownership,cropping intensity,per capita income,irrigation intensity,share of institutional credit,food grain productivity,crop diversification,awareness of minimum support price,knowledge sharing with fellow farmers,and young and working population,as well as better transportation facilities and membership of agricultural credit societies are influencing indicators responsible for higher agricultural sustainability in TGPR compared with EHR.Although,the scores of environmental sustainability indicators of EHR are quite good,its scores of social and economic security indicators are fairly low,putting it at the bottom of the rank of agricultural sustainability index among the 14 mainstream agroclimatic regions in India.This demonstrates the need of understanding agricultural sustainability in relation to social and economic dimensions.In a nation as diverse and complicated as India,it is the social structure that determines the health of the economy and environment.Last but not least,the sustainability assessment methodology may be used in a variety of India's agro-climatic regions.
文摘As one of the Special Economic Zones since the reform and opening up, Zhuhai has developed during the past 30 years. Its economic development, industrial structure and ecological environment have undergone great changes. Research on changes in Zhuhai’s land ecological security is of great significance. Using relevant data from 2007-2012, this study established a land ecological security assessment system based on the PSR conceptual framework model. The system contained 18 indicators from 3 aspects according to the concrete features of Zhuhai. Then we used the matterelement analysis and the improved entropy weight to analyze and evaluate the land ecological security of Zhuhai. The results showed that: from 2007 to 2012, the levels of the land ecological security of Zhuhai were “secure”, and the value increased year by year;as the land ecological security response value increased, Zhuhai was capable of solving land ecosystem problems. However, it should be noted that the structure of land ecosystem in Zhuhai has not formed and that rapid expansion of construction land has caused the shortage of cultivated land and other issues. Measures should be taken to control the construction area, improve land intensive utilization and improve the land ecological security.
基金supported by the open project of the Key Laboratory in Xinjiang Uygur Autonomous Region of China(No.2023D04058)the Major Science and Technology Program of Xinjiang Uygur Autonomous Region(No.2022A03013-1)+12 种基金the National Key Research and Development Program of China(No.2022YFC2205203)the National Natural Science Foundation of China(NSFC,Grant Nos.12303053,12288102,11988101,U1838109,12041304,12041301,11873080,12133004,12203094 and U1631106)the Chinese Academy of Sciences Foundation of the young scholars of western(No.2020XBQNXZ-019)the National SKA Program of China(2020SKA0120100)Z.G.W.is supported by the Tianshan Talent Training Program(NO.2023TSYCCX0100)2021 project Xinjiang Uygur autonomous region of China for Tianshan elitesthe Youth Innovation Promotion Association of CAS under No.2023069J.L.C.is supported by the Natural Science Foundation of Shanxi Province(20210302123083)H.W.is supported by the ScientificTechnological Innovation Programs of Higher Education Institutions in Shanxi(grant No.2021L480)W.M.Y.is supported by the CAS Jianzhihua projectH.G.W.is supported by the 2018 project of Xinjiang Uygur autonomous region of China for flexibly fetching in upscale talentsW.H.is supported by the CAS Light of West China Program No.2019-XBQNXZ-B-019。
文摘We have conducted a comprehensive investigation into the bright single pulse emission from PSR B1133+16using the Giant Metrewave Radio Telescope.High time resolution data(61μs)were obtained at a center frequency of 322 MHz with a bandwidth of 32 MHz over a continuous observation period of 7.45 hr.A total of 1082 bright pulses were sporadically detected with peak flux densities ranging from 10 to 23 times stronger than the average pulse profile.However,no giant pulse-like emission with a relative pulse energy larger than 10 and extremely short duration was detected,indicating that these bright pulses cannot be categorized as giant pulse emission.The majority of these bright pulses are concentrated in pulse phases at both the leading and trailing windows of the average pulse profile,with an occurrence ratio of approximately 2.74.The pulse energy distribution for all individual pulses can be described by a combination of two Gaussian components and a cutoff power-law with an index of α=-3.2.An updated nulling fraction of 15.35%±0.45% was determined from the energy distribution.The emission of individual pulses follows a log-normal distribution in peak flux density ratio.It is imperative that regular phase drifting in bright pulse sequence is identified in both the leading and trailing components for the first time.Possible physical mechanisms are discussed in detail to provide insights into these observations.
基金supported in partially by the National Society Science Fund of China(Grant No.09CJY020)the Special Fund of State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,China(Grant No. 2011585312)+1 种基金the Fundamental Research Funds for the Central Universities of Hohai University2010 Jiangsu Province Qing Lan Project
文摘Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more and more attention of the researchers.Aiming at evaluating its ecological and economic system health,a multi-objective evaluation framework called PressureState-Response(PSR) was established to describe the ecological and economic health situations.Meanwhile,an integrative set pair model combining set pair analysis(SPA) and fuzzy analytic hierarchy process(FAHP) was proposed to assess the ecological and economic system.Then the EES status of five northwest provinces(Shanxi,Gansu,Qinghai,Ningxia and Xinjiang) of Northwest region in China was evaluated during 1985 to 2009.The EES development trends of five provinces are obtained.In general,the health values of five provinces showed a rising trend.The health values of five provinces grew rapidly during 1985 to 2000.After 2000,the health values of five provinces still followed the present growth trend,but the growth is relatively smooth.The results show that the method proposed is effective for assessing the health of ecological and economic system.
基金supported by the National Natural Science Foundation of China(NSFC,grant No.U1838203)International Partnership Program of Chinese Academy of Sciences(grant No.113111KYSB20190020)。
文摘We analyzed the spectral properties and pulse profile of PSR J1811-1925,a pulsar located in the center of composite supernova remnant(SNR)G11.2-0.3,by using high timing resolution archival data from the Nuclear Spectroscopic Telescope Array Mission(NuSTAR).Analysis of archival Chandra data over different regions rules out the SNR shell as the site of the hard X-ray emission while spectral analysis indicates that the NuSTAR photons originate in the pulsar and its nebula.The pulse profile exhibits a broad single peak up to 35 keV.The jointed spectrum by combining NuSTAR and Chandra can be well fitted by a power-law model with a photon index ofΓ=1.58±0.04.The integrated flux of jointed spectrum over 1-10 keV is 3.36×10^(-12)erg cm^(-2)s^(-1).The spectrum of pulsar having photon indexΓ=1.33±0.06 and a 1-10 keV flux of 0.91×10^(-12)erg cm^(-2)s^(-1).We also performed the phase-resolved spectral analysis by splitting the whole pulse-on phase into five phase bins.The photon indices of the bins are all around 1.4,indicating that the photon index does not evolve with the phase.
文摘从城市土地利用中的人地关系分析入手,阐述了城市土地集约利用的 PSR 概念系统,并据此构建了评价指标体系,然后采用主成分分析法,从区域空间的角度对浙江省11个地级市的城市土地集约利用情况进行了测度和评价。结果表明:①浙江省东北部地区城市土地集约利用效益较高,西南部偏低,这主要是由于区位优势和产业结构的差异所致;②通过相关分析,发现浙江省城市土地集约利用水平与其 PSR 系统的协调度成正相关。这说明 PSR 各子系统及其内部各因子之间的协调性很大程度上可以反映城市土地集约利用的均衡度,模型可信度比较高,可供有关方面参考借鉴。