It is well understood that for conventional survey designs the set of unordered distinct units in a sample is a minimally sufficient statistic. This means that for inferential statistic of the sample, the value of the...It is well understood that for conventional survey designs the set of unordered distinct units in a sample is a minimally sufficient statistic. This means that for inferential statistic of the sample, the value of the sampled units rather than the sample design is important. Sampling rare populations presents distinct challenges. Examples of rare populations are in biology with rare and endangered animals where there are only a few remaining individuals, or in social science, with the low incidence of people from an unusually high （or low） income group. Sampling rare populations tends to result in the case that many of the sample units do not contain information on the characteristic of interest （e.g., the rare animal, or people from the unusual income group）. For finite rare populations the set of unordered distinct rare-units in a sample is a minimally sufficient statistic. In an example case study of a rare buttercup, the properties of the minimal sufficient estimator are explored. We compare the efficiency of the estimator for the population total based on the minimally sufficient statistic, with the standard estimator for a range of sample sizes. The variance of the minimally sufficient estimator was always smaller than the variance of the sufficient estimator. For rare populations where non-rare units can be distinguished from rare units because they have the same fixed value, the minimal sufficient statistic is the rare units, if any, in the sample.展开更多
A new concept of(Φ,ρ,α)-V-invexity for differentiable vector-valued functions is introduced,which is a generalization of differentiable scalar-valued(Φ,ρ)-invexity.Based upon the(Φ,ρ,α)-V-invex functions,suffi...A new concept of(Φ,ρ,α)-V-invexity for differentiable vector-valued functions is introduced,which is a generalization of differentiable scalar-valued(Φ,ρ)-invexity.Based upon the(Φ,ρ,α)-V-invex functions,sufficient optimality conditions and MondWeir type dual theorems are derived for a class of nondifferentiable multiobjective fractional programming problems in which every component of the objective function and each constraint function contain a term involving the support function of a compact convex set.展开更多
To determine the sufficiency and deficiency indices of soil available Zn by the Agro Services International （ASI） method （ASI-Zn） for Zn fertilizer recommendation in rice production in the alluvial soil of the coa...To determine the sufficiency and deficiency indices of soil available Zn by the Agro Services International （ASI） method （ASI-Zn） for Zn fertilizer recommendation in rice production in the alluvial soil of the coastal Yellow Sea, the relationship between relative rice yield and soil available ASI-Zn concentration was analyzed from a ten-field experiment with various soil test classes ranging from low to high fertility in 2005 and 2006, and nine Zn fertilizer application rates （0, 7.5 15, 22.5, 30, 37.5, 45, 52.5 and 60 kg Zn/ha） arranged at random with three replications in each field. There was a significant quadratic relationship between soil available ASI-Zn and rice yield, and a significant linear relationship between soil available ASI-Zn concentration and Zn fertilization rate. For rice variety Wuyujing 3, soil available ASI-Zn was deficient when the value was at lower than 1 mg Zn/L, low at 1 to 2 mg Zn/L, sufficient at 1 to 2 mg Zn/L, excessive at higher than 7.5 mg Zn/L. Thus, Zn fertilizer recommendation could be done according to the sufficiency and deficiency indices of soil ASI-Zn. For most of alluvial soils of the coastal Yellow Sea in the study, the available ASI-Zn was lower than 1 mg Zn/L, and then the optimum application rate of Zn fertilizer was about 20 kg Zn/ha.展开更多
The exponential growth of food demand due to the increasing global population has the potential to seriously threaten the quality and quantity of food supplies due to climate change.This study explores the utilisation...The exponential growth of food demand due to the increasing global population has the potential to seriously threaten the quality and quantity of food supplies due to climate change.This study explores the utilisation of green urban spaces for achieving food self-sufficiency by investigating the extent to which sustainable urban farms could be used to reduce the consumption of imported produce in the UK.It also examines urban farming stakeholders'perspective on how food self-sufficiency can help realise the SDGs especially SDG 2(Zero hunger)and SDG 13(Climate action).The study adopts a mixed method approach through a survey with 115 respondents and semi-structured interviews conducted with 12 respondents from 4 different urban farming stakeholder groups.The findings of this study presented a strong correlation between stakeholders who had concerns about where their food came from and the carbon footprint of imported produce.The research shows that,urban farms will no doubt play a vital role in the future of food security in our cities/communities and that the SDGs could be realised through sustainable urban farms implemented within the relevant planning regulations/policies.展开更多
A class of functions called quasi B s invex and pseudo B s invex functions are introduced by using the concept of symmetric gradient. The examples of quasi B s invex and pseudo B s invex functions are given. The suffi...A class of functions called quasi B s invex and pseudo B s invex functions are introduced by using the concept of symmetric gradient. The examples of quasi B s invex and pseudo B s invex functions are given. The sufficient optimality conditions and Mond Weir type duality results are obtained for a nondifferentiable nonlinear semi infinite programming problem involving quasi B s invex and pseudo B s invex functions.展开更多
This paper provides further contributions to the theory of linear sufficiency in the general Gauss-Markov model E(y)=Xβ,Var (y)=V.The notion of linear sufficiency introduced by Baksalary and Kala(1981) and Drygas(198...This paper provides further contributions to the theory of linear sufficiency in the general Gauss-Markov model E(y)=Xβ,Var (y)=V.The notion of linear sufficiency introduced by Baksalary and Kala(1981) and Drygas(1983) is extended for any specific estimable function c′β.Some general results with respect to the extended concept are obtained.An essential result concerning the former notion is a direct consequence of this paper.展开更多
Taxonomic sufficiency(TS)refers to identifying taxa to a taxonomic level sufficient to detect community changes in stressed environments and may provide a cost-effective approach in routine monitoring programs.However...Taxonomic sufficiency(TS)refers to identifying taxa to a taxonomic level sufficient to detect community changes in stressed environments and may provide a cost-effective approach in routine monitoring programs.However,there is still limited information regarding the seasonal impact of applying TS and its implications for the ecological quality evaluation in the estuarine ecosystem.This study investigated the relationship between the multivariate-AZTI’s Marine Biotic Index(M-AMBI)and environmental variables in three seasons(i.e.,spring,summer,and autumn)in the Liaohe River Estuary.We tested the reliability of TS for simplifying the M-AMBI methodology.The results showed that family and genus level data could reproduce the spatial-temporal patterns of community structure at the species level.The M-AMBI values showed a consistent spatial distribution pattern in all sampling seasons,with a decreasing trend with the increasing distance from the estuary mouth.Both genus and family level data performed nearly as well as species level in detecting the seasonal variations of pollutants(i.e.,nutrients and total organic content).The family level M-AMBI was feasible to discern stress in the Liaohe River Estuary because of the high aggregation ratios at different taxonomic levels in all sampling seasons.These findings suggest that applying taxonomic sufficiency based on the M-AMBI provides an efficient approach for evaluating ecological quality in the Liaohe River Estuary.展开更多
Capacity for grain self-sufficiency on the Tibetan Plateau(TP)is an important basis for ensuring social stability and regional sustainability.Thus,based on county-level statistical data for population,grain production...Capacity for grain self-sufficiency on the Tibetan Plateau(TP)is an important basis for ensuring social stability and regional sustainability.Thus,based on county-level statistical data for population,grain production and consumption,we analyzed patterns and trends in grain supply and demand at regional,provincial,and county levels on the TP between 1985 and 2016.We applied two indices to evaluate capacity for grain self-sufficiency and found that the regional average self-sufficiency rate increased quickly by 1.97%/a since 1989,reaching 173.03%on the plateau over the period between 2010 and 2016.This indicates that grain supply in this region is able to fully meet demand.In addition,all provinces apart from Xinjiang exhibited similar increasing trends,attaining grain self-sufficiency during 2010–2016.Furthermore,59%of counties attained grain self-sufficiency over this period,mainly distributed in southern Tibet,in the Sichuan-Tibet junction area,and in eastern Qinghai Province.A number of gaps in grain supply and demand occurred within the headwater regions of the Yangtze and Yellow rivers as well as on the Qiangtang Plateau.Grain self-sufficiency significantly increased over the study period in 36%of counties,mainly distributed in the agricultural areas of southeastern Tibet and in eastern Qinghai.Across the whole plateau,capacity for grain self-sufficiency substantially increased between 1985 and 2016,although serious spatial imbalances remain.展开更多
The purpose of this paper is to suggest the concept of sufficiency economy philosophy to be used in tourism business,especially in human resource development(HRD).This paper covers the analysis and synthesis from lite...The purpose of this paper is to suggest the concept of sufficiency economy philosophy to be used in tourism business,especially in human resource development(HRD).This paper covers the analysis and synthesis from literature review,the meaning of sufficiency economy philosophy,sustainable development and human resource.The result has shown that the sufficiency economy philosophy is a measure of well-being(Nothing can be developed sustainably like HRD.Tourism business is a service product that depends on human resources).That is the reason why the sufficiency economy philosophy should be implemented for sustainable HRD in tourism business.展开更多
A building integrated photovoltaic (PV) and fuel cell (FC) system is proposed for assessment of the energy self-sufficiency rate in a city in Japan. The electricity consumed in the building is mainly supplied by solar...A building integrated photovoltaic (PV) and fuel cell (FC) system is proposed for assessment of the energy self-sufficiency rate in a city in Japan. The electricity consumed in the building is mainly supplied by solar panels, while the gap between the energy demand and supply is solved by the FC that is powered by the H2 produced by water electrolysis with surplus power of PV. A desktop case study of using the proposed system in Tsu city which is located in central part of Japan, has been conducted. The results found that the self-sufficiency rates of PV system to electricity demand of households (RPV) during the daytime in April and July are higher than those in January and October. The results also reveal that the self-sufficiency rate of FC system to the electricity demand (RFC) is 15% - 38% for the day when the mean amount of horizontal solar radiation is obtained in January, April, July and October. In addition, it is found the optimum tilt angle of solar panel installed on the roof of the buildings should be 0 degree, i.e., placed horizontally.展开更多
Renewable energy sources, including bioenergy, are presently attracting considerable attention as possible substitutes for fossil fuels. Among the various sources of bioenergy, biomass can arguably play a significant ...Renewable energy sources, including bioenergy, are presently attracting considerable attention as possible substitutes for fossil fuels. Among the various sources of bioenergy, biomass can arguably play a significant role in the reduction of greenhouse gases and the provision of a stable energy supply. However, the use of fossil fuels continues in the production of bioenergy. Consequently, the overall extent to which biomass utilization for energy can reduce carbon dioxide emissions as a substitute for fossil fuels and whether this can improve the energy self-sufficiency rate remains largely unknown. This study responds to these questions using a case of a Japanese rural community using firewood for residential heating. The results showed that woody biomass utilization for energy is able to both reduce the dependence on fossil fuels and mitigate climate change. These findings offer new insights into the development of sustainability in rural communities.展开更多
Rice is the main food of Sierra Leoneans and an important source of employment and income for rural communities. According to the West African Rice Development Association report, annual consumption of rice is amongst...Rice is the main food of Sierra Leoneans and an important source of employment and income for rural communities. According to the West African Rice Development Association report, annual consumption of rice is amongst the highest in SubSaharan Africa（SSA）, 104 kg. Mainly, small scale farmers who are resource poor on both the upland and various lowlands grow rice. Sierra Leone has not been able to produce enough rice to meet its local consumption demand for a very long time now. 530 000 MT of milled rice is the required consumption need of the Sierra Leonean population per annum. In 2007, national paddy rice production was projected at 638 000 MT. The level of rice self-sufficiency rose from 50.57% in 2002 to 62.15% in 2006 and then to 63.49% in 2007. The remainder must be imported at increasingly expensive prices in the current situation of high food prices, which includes rice. The price of rice has seen a steady increase in the entire country. What most affected by this, is the low-income urban and peri-urban households. The promotion of domestic rice production is therefore a key element in the strategies for improving rice self-sufficiency, stimulating economic growth and increasing rural income. Therefore, supporting rice production programme is the only solution to pull the country out of the worsening rice situation and maintain the present trend in rice self-sufficiency. Therefore, having an understanding of the strategic interventions in rice production in Sierra Leone is an important ingredient in the promotion and attainment of rice self-sufficiency.展开更多
We investigate the weight-based food self-sufficiency ratio (WSSR) for Japan over a 50-year period (1961-2011) by applying factorial component analysis technique in order to measure the changes of the WSSR quantitativ...We investigate the weight-based food self-sufficiency ratio (WSSR) for Japan over a 50-year period (1961-2011) by applying factorial component analysis technique in order to measure the changes of the WSSR quantitatively. Quantitative data analysis is employed to determine the drivers of those changes. Numerical results show that Japan experienced a drastic decline in its food self-sufficiency ratio (FSSR) during the above period. The factorial component analysis shows that such a decline was caused by the changes in the FSSR of the food groups/items, not in the quantity of the food supply. A number of characteristics of those changes are presented and a list of major food groups that have major impacts on the changes is constructed. The findings in this paper reiterate the alarming food security problem in Japan and provide clear insight into the causes of this problem. The findings in this study pick up where previous studies have left off, aid the food-related policy-making process and identify new ideas for future food research.展开更多
文摘It is well understood that for conventional survey designs the set of unordered distinct units in a sample is a minimally sufficient statistic. This means that for inferential statistic of the sample, the value of the sampled units rather than the sample design is important. Sampling rare populations presents distinct challenges. Examples of rare populations are in biology with rare and endangered animals where there are only a few remaining individuals, or in social science, with the low incidence of people from an unusually high （or low） income group. Sampling rare populations tends to result in the case that many of the sample units do not contain information on the characteristic of interest （e.g., the rare animal, or people from the unusual income group）. For finite rare populations the set of unordered distinct rare-units in a sample is a minimally sufficient statistic. In an example case study of a rare buttercup, the properties of the minimal sufficient estimator are explored. We compare the efficiency of the estimator for the population total based on the minimally sufficient statistic, with the standard estimator for a range of sample sizes. The variance of the minimally sufficient estimator was always smaller than the variance of the sufficient estimator. For rare populations where non-rare units can be distinguished from rare units because they have the same fixed value, the minimal sufficient statistic is the rare units, if any, in the sample.
基金National Natural Science Foundation of China(No.11071110)
文摘A new concept of(Φ,ρ,α)-V-invexity for differentiable vector-valued functions is introduced,which is a generalization of differentiable scalar-valued(Φ,ρ)-invexity.Based upon the(Φ,ρ,α)-V-invex functions,sufficient optimality conditions and MondWeir type dual theorems are derived for a class of nondifferentiable multiobjective fractional programming problems in which every component of the objective function and each constraint function contain a term involving the support function of a compact convex set.
文摘To determine the sufficiency and deficiency indices of soil available Zn by the Agro Services International （ASI） method （ASI-Zn） for Zn fertilizer recommendation in rice production in the alluvial soil of the coastal Yellow Sea, the relationship between relative rice yield and soil available ASI-Zn concentration was analyzed from a ten-field experiment with various soil test classes ranging from low to high fertility in 2005 and 2006, and nine Zn fertilizer application rates （0, 7.5 15, 22.5, 30, 37.5, 45, 52.5 and 60 kg Zn/ha） arranged at random with three replications in each field. There was a significant quadratic relationship between soil available ASI-Zn and rice yield, and a significant linear relationship between soil available ASI-Zn concentration and Zn fertilization rate. For rice variety Wuyujing 3, soil available ASI-Zn was deficient when the value was at lower than 1 mg Zn/L, low at 1 to 2 mg Zn/L, sufficient at 1 to 2 mg Zn/L, excessive at higher than 7.5 mg Zn/L. Thus, Zn fertilizer recommendation could be done according to the sufficiency and deficiency indices of soil ASI-Zn. For most of alluvial soils of the coastal Yellow Sea in the study, the available ASI-Zn was lower than 1 mg Zn/L, and then the optimum application rate of Zn fertilizer was about 20 kg Zn/ha.
文摘The exponential growth of food demand due to the increasing global population has the potential to seriously threaten the quality and quantity of food supplies due to climate change.This study explores the utilisation of green urban spaces for achieving food self-sufficiency by investigating the extent to which sustainable urban farms could be used to reduce the consumption of imported produce in the UK.It also examines urban farming stakeholders'perspective on how food self-sufficiency can help realise the SDGs especially SDG 2(Zero hunger)and SDG 13(Climate action).The study adopts a mixed method approach through a survey with 115 respondents and semi-structured interviews conducted with 12 respondents from 4 different urban farming stakeholder groups.The findings of this study presented a strong correlation between stakeholders who had concerns about where their food came from and the carbon footprint of imported produce.The research shows that,urban farms will no doubt play a vital role in the future of food security in our cities/communities and that the SDGs could be realised through sustainable urban farms implemented within the relevant planning regulations/policies.
基金the Natural Science Foundation of Shaanxi Province and the Science Foundation of Shaanxi Provincial Educational CommitteeP.R.China
文摘A class of functions called quasi B s invex and pseudo B s invex functions are introduced by using the concept of symmetric gradient. The examples of quasi B s invex and pseudo B s invex functions are given. The sufficient optimality conditions and Mond Weir type duality results are obtained for a nondifferentiable nonlinear semi infinite programming problem involving quasi B s invex and pseudo B s invex functions.
基金the Natural Science Foundation of Guangdong Province(0 1 0 4 86 )
文摘This paper provides further contributions to the theory of linear sufficiency in the general Gauss-Markov model E(y)=Xβ,Var (y)=V.The notion of linear sufficiency introduced by Baksalary and Kala(1981) and Drygas(1983) is extended for any specific estimable function c′β.Some general results with respect to the extended concept are obtained.An essential result concerning the former notion is a direct consequence of this paper.
基金The National Marine Public Welfare Research Project of China under contract No.201305030the Open Fund from Observation and Research Station of Bohai Strait Eco-Corridor under contract No.BH202201.
文摘Taxonomic sufficiency(TS)refers to identifying taxa to a taxonomic level sufficient to detect community changes in stressed environments and may provide a cost-effective approach in routine monitoring programs.However,there is still limited information regarding the seasonal impact of applying TS and its implications for the ecological quality evaluation in the estuarine ecosystem.This study investigated the relationship between the multivariate-AZTI’s Marine Biotic Index(M-AMBI)and environmental variables in three seasons(i.e.,spring,summer,and autumn)in the Liaohe River Estuary.We tested the reliability of TS for simplifying the M-AMBI methodology.The results showed that family and genus level data could reproduce the spatial-temporal patterns of community structure at the species level.The M-AMBI values showed a consistent spatial distribution pattern in all sampling seasons,with a decreasing trend with the increasing distance from the estuary mouth.Both genus and family level data performed nearly as well as species level in detecting the seasonal variations of pollutants(i.e.,nutrients and total organic content).The family level M-AMBI was feasible to discern stress in the Liaohe River Estuary because of the high aggregation ratios at different taxonomic levels in all sampling seasons.These findings suggest that applying taxonomic sufficiency based on the M-AMBI provides an efficient approach for evaluating ecological quality in the Liaohe River Estuary.
基金Strategic Priority Research Program of the Chinese Academy of Sciences,No.XDA20040301National Natural Science Foundation of China,No.41771111+3 种基金The Youth Innovation Promotion Association,Chinese Academy of Sciences,No.2018071Fund for Excellent Young Talents in Institute of Geographic Sciences and Natural Resources Research,CAS,No.2016RC201Hebei Natural Science Foundation,No.D2019205123Research Fund of Hebei Normal University,No.L052018Z09。
文摘Capacity for grain self-sufficiency on the Tibetan Plateau(TP)is an important basis for ensuring social stability and regional sustainability.Thus,based on county-level statistical data for population,grain production and consumption,we analyzed patterns and trends in grain supply and demand at regional,provincial,and county levels on the TP between 1985 and 2016.We applied two indices to evaluate capacity for grain self-sufficiency and found that the regional average self-sufficiency rate increased quickly by 1.97%/a since 1989,reaching 173.03%on the plateau over the period between 2010 and 2016.This indicates that grain supply in this region is able to fully meet demand.In addition,all provinces apart from Xinjiang exhibited similar increasing trends,attaining grain self-sufficiency during 2010–2016.Furthermore,59%of counties attained grain self-sufficiency over this period,mainly distributed in southern Tibet,in the Sichuan-Tibet junction area,and in eastern Qinghai Province.A number of gaps in grain supply and demand occurred within the headwater regions of the Yangtze and Yellow rivers as well as on the Qiangtang Plateau.Grain self-sufficiency significantly increased over the study period in 36%of counties,mainly distributed in the agricultural areas of southeastern Tibet and in eastern Qinghai.Across the whole plateau,capacity for grain self-sufficiency substantially increased between 1985 and 2016,although serious spatial imbalances remain.
文摘The purpose of this paper is to suggest the concept of sufficiency economy philosophy to be used in tourism business,especially in human resource development(HRD).This paper covers the analysis and synthesis from literature review,the meaning of sufficiency economy philosophy,sustainable development and human resource.The result has shown that the sufficiency economy philosophy is a measure of well-being(Nothing can be developed sustainably like HRD.Tourism business is a service product that depends on human resources).That is the reason why the sufficiency economy philosophy should be implemented for sustainable HRD in tourism business.
文摘A building integrated photovoltaic (PV) and fuel cell (FC) system is proposed for assessment of the energy self-sufficiency rate in a city in Japan. The electricity consumed in the building is mainly supplied by solar panels, while the gap between the energy demand and supply is solved by the FC that is powered by the H2 produced by water electrolysis with surplus power of PV. A desktop case study of using the proposed system in Tsu city which is located in central part of Japan, has been conducted. The results found that the self-sufficiency rates of PV system to electricity demand of households (RPV) during the daytime in April and July are higher than those in January and October. The results also reveal that the self-sufficiency rate of FC system to the electricity demand (RFC) is 15% - 38% for the day when the mean amount of horizontal solar radiation is obtained in January, April, July and October. In addition, it is found the optimum tilt angle of solar panel installed on the roof of the buildings should be 0 degree, i.e., placed horizontally.
文摘Renewable energy sources, including bioenergy, are presently attracting considerable attention as possible substitutes for fossil fuels. Among the various sources of bioenergy, biomass can arguably play a significant role in the reduction of greenhouse gases and the provision of a stable energy supply. However, the use of fossil fuels continues in the production of bioenergy. Consequently, the overall extent to which biomass utilization for energy can reduce carbon dioxide emissions as a substitute for fossil fuels and whether this can improve the energy self-sufficiency rate remains largely unknown. This study responds to these questions using a case of a Japanese rural community using firewood for residential heating. The results showed that woody biomass utilization for energy is able to both reduce the dependence on fossil fuels and mitigate climate change. These findings offer new insights into the development of sustainability in rural communities.
文摘Rice is the main food of Sierra Leoneans and an important source of employment and income for rural communities. According to the West African Rice Development Association report, annual consumption of rice is amongst the highest in SubSaharan Africa（SSA）, 104 kg. Mainly, small scale farmers who are resource poor on both the upland and various lowlands grow rice. Sierra Leone has not been able to produce enough rice to meet its local consumption demand for a very long time now. 530 000 MT of milled rice is the required consumption need of the Sierra Leonean population per annum. In 2007, national paddy rice production was projected at 638 000 MT. The level of rice self-sufficiency rose from 50.57% in 2002 to 62.15% in 2006 and then to 63.49% in 2007. The remainder must be imported at increasingly expensive prices in the current situation of high food prices, which includes rice. The price of rice has seen a steady increase in the entire country. What most affected by this, is the low-income urban and peri-urban households. The promotion of domestic rice production is therefore a key element in the strategies for improving rice self-sufficiency, stimulating economic growth and increasing rural income. Therefore, supporting rice production programme is the only solution to pull the country out of the worsening rice situation and maintain the present trend in rice self-sufficiency. Therefore, having an understanding of the strategic interventions in rice production in Sierra Leone is an important ingredient in the promotion and attainment of rice self-sufficiency.
文摘We investigate the weight-based food self-sufficiency ratio (WSSR) for Japan over a 50-year period (1961-2011) by applying factorial component analysis technique in order to measure the changes of the WSSR quantitatively. Quantitative data analysis is employed to determine the drivers of those changes. Numerical results show that Japan experienced a drastic decline in its food self-sufficiency ratio (FSSR) during the above period. The factorial component analysis shows that such a decline was caused by the changes in the FSSR of the food groups/items, not in the quantity of the food supply. A number of characteristics of those changes are presented and a list of major food groups that have major impacts on the changes is constructed. The findings in this paper reiterate the alarming food security problem in Japan and provide clear insight into the causes of this problem. The findings in this study pick up where previous studies have left off, aid the food-related policy-making process and identify new ideas for future food research.
