AIM:To compare and analyse the diagnostic efficacy of the College of Optometrists Vision Development Quality of Life Questionnaire(COVD-QOL)and the Convergence Insufficiency Symptom Survey(CISS)in detecting convergenc...AIM:To compare and analyse the diagnostic efficacy of the College of Optometrists Vision Development Quality of Life Questionnaire(COVD-QOL)and the Convergence Insufficiency Symptom Survey(CISS)in detecting convergence insufficiency and to compare their diagnostic value in clinical applications.METHODS:Using the diagnostic test method,62 adult patients with convergence insufficiency(age:24.74±3.75y)and 62 normal participants(age:23.61±3.13y)who visited the Optometry Clinic of West China Hospital of Sichuan University from April 2021 to January 2023 were included.All subjects completed the CISS and COVD-QOL.Statistical analysis of the sensitivity and specificity of the CISS and COVD-QOL and comparison and joint experimental analysis of their diagnostic efficacy were performed.RESULTS:The sensitivity of the CISS and COVD-QOL for convergence insufficiency was 64.5%and 71.0%,respectively,while the specificity was 96.8%and 67.7%,respectively.Compared to the CISS alone,the combination of the CISS and COVD-QOL demonstrated lower sensitivity and specificity.The areas under the receiver operating characteristic curve of CISS,COVD-QOL and CISS combined with COVD-QOL were 0.806,0.694 and 0.782,respectively.CONCLUSION:Considering the low sensitivity of the CISS and the low specificity of the COVD-QOL,it is recommended to supplement these questionnaires with other screening tests for the detection of convergence insufficiency.展开更多
Background Four-chambered stomach including the forestomachs(rumen,reticulum,and omasum)and abomasum allows ruminants convert plant fiber into high-quality animal products.The early development of this four-chambered ...Background Four-chambered stomach including the forestomachs(rumen,reticulum,and omasum)and abomasum allows ruminants convert plant fiber into high-quality animal products.The early development of this four-chambered stomach is crucial for the health and well-being of young ruminants,especially the immune development.However,the dynamics of immune development are poorly understood.Results We investigated the early gene expression patterns across the four-chambered stomach in Hu sheep,at 5,10,15,and 25 days of age.We found that forestomachs share similar gene expression patterns,all four stomachs underwent widespread activation of both innate and adaptive immune responses from d 5 to 25,whereas the metabolic function were significantly downregulated with age.We constructed a cell landscape of the four-chambered stomach using single-cell sequencing.Integrating transcriptomic and single-cell transcriptomic analyses revealed that the immune-associated module hub genes were highly expressed in T cells,monocytes and macrophages,as well as the defense-associated module hub genes were highly expressed in endothelial cells in the four-stomach tissues.Moreover,the non-immune cells such as epithelial cells play key roles in immune maturation.Cell communication analysis predicted that in addition to immune cells,non-immune cells recruit immune cells through macrophage migration inhibitory factor signaling in the forestomachs.Conclusions Our results demonstrate that the immune and defense responses of four stomachs are quickly developing with age in lamb's early life.We also identified the gene expression patterns and functional cells associated with immune development.Additionally,we identified some key receptors and signaling involved in immune regulation.These results help to understand the early life immune development at single-cell resolution,which has implications to develop nutritional manipulation and health management strategies based on specific targets including key receptors and signaling pathways.展开更多
In this paper, the Life Cycle of Urban Development was firstly analyzed, and the phases of Life Cycle Assessment applied to Urban Development (ULCA) were described. As a case study, ULCA was applied in the environment...In this paper, the Life Cycle of Urban Development was firstly analyzed, and the phases of Life Cycle Assessment applied to Urban Development (ULCA) were described. As a case study, ULCA was applied in the environmental impact assessment of the land readjustment project of Hyogo District of Saga, Japan. In addition, mitigation proposals for reducing CO2 were also presented and the relevant environmental ef-fects were simulated.展开更多
Social achievement in the world is dependent to a great extent on the development of mineral resources. A changing pattern of the Life Cycle in mineral consumption, with a general pattern of introduction, growth, sta...Social achievement in the world is dependent to a great extent on the development of mineral resources. A changing pattern of the Life Cycle in mineral consumption, with a general pattern of introduction, growth, stability and decline, is seen as a determinant factor not only to the transformation of industrial structure, but also to the infrastructural construction, industrial location, the spatial organization of urban development as well as regional environmental protection.展开更多
Quality of Life (QOL) is a multiphase conception, including physical, mental and social factors, and can overall reflect health status of the human. At present, QOL has become a relevant measure of efficacy of treatme...Quality of Life (QOL) is a multiphase conception, including physical, mental and social factors, and can overall reflect health status of the human. At present, QOL has become a relevant measure of efficacy of treatment in clinical trials. Its use is spreading, and its importance is growing as a valid indicator of whether or not a medical treatment is展开更多
China is the most populous country in the world.The total Population on the mainland of China has in-creased from 540 million in 1949 to 1.18 billion by the end of 1993.China adopted a population policy by namc of&quo...China is the most populous country in the world.The total Population on the mainland of China has in-creased from 540 million in 1949 to 1.18 billion by the end of 1993.China adopted a population policy by namc of"controlling population growth and im-proving the quality of the human resources',which has been deeply rooted in the hearts of the Chinese pcoplc.The overw helming majority of the Chinese people have recognized the necessity for implementing the family planning programme not only for the sustained devel-opment of the country,but also for the benefits of their own familie cs.展开更多
The research on the tire industry cluster based on life cycle theory can be carried out by a four stage periods,namely initial period,growth period,maturity period,and recession period.This paper analyzes on the possi...The research on the tire industry cluster based on life cycle theory can be carried out by a four stage periods,namely initial period,growth period,maturity period,and recession period.This paper analyzes on the possible risks taken in each life cycle period as well as proposes corresponding suggestions to strengthen the research by looking into the conditions and factors of the continuous sustainable development process in a tire industry.展开更多
Based on an analysis of the limitations of conventional production component methods for natural gas development planning,this study proposes a new one that uses life cycle models for the trend fitting and prediction ...Based on an analysis of the limitations of conventional production component methods for natural gas development planning,this study proposes a new one that uses life cycle models for the trend fitting and prediction of production.In this new method,the annual production of old and new wells is predicted by year first and then is summed up to yield the production for the planning period.It shows that the changes in the production of old wells in old blocks can be fitted and predicted using the vapor pressure model(VPM),with precision of 80%e95%,which is 6.6%e13.2%higher than that of other life cycle models.Furthermore,a new production prediction process and method for new wells have been established based on this life cycle model to predict the production of medium-to-shallow gas reservoirs in western Sichuan Basin,with predication error of production rate in 2021 and 2022 being 6%and 3%respectively.The new method can be used to guide the medium-and long-term planning or annual scheme preparation for gas development.It is also applicable to planning for large single gas blocks that require continuous infill drilling and adjustment to improve gas recovery.展开更多
With the development of modern industry and ever more complex structural loads,the possibility of fatigue failure is increasing.Fatigue analysis can be used to evaluate the service life of components and reduce the pr...With the development of modern industry and ever more complex structural loads,the possibility of fatigue failure is increasing.Fatigue analysis can be used to evaluate the service life of components and reduce the probability of accidents.Therefore,the development and application of fatigue-analysis technology have important research significance.This paper collects information from a wide field of literature and summarizes the current status of fatigue-analysis research.It covers related theoretical knowledge,fatigue-life prediction methods,and fatigue design methods and their application scenarios,and it summarizes the challenges and research hotspots in the field.On the basis of this examination,future development directions of fatigue-life prediction methods are proposed.The conclusions will have a certain guiding role in the development of fatigue-analysis methods.展开更多
In December 11,2018,the fall armyworm(FAW),Spodoptera frugiperda invaded China and has since impacted local maize,sorghum and other crops.Here,we draw on laboratory experiments to show how different host crops(i.e.,ma...In December 11,2018,the fall armyworm(FAW),Spodoptera frugiperda invaded China and has since impacted local maize,sorghum and other crops.Here,we draw on laboratory experiments to show how different host crops(i.e.,maize,sorghum,wheat and rice)and artificial diet affect larval growth and adult reproduction of one local FAW strain.Larval diet affected development duration,pupation rate,survival and emergence rate of pupae,and S.frugiperda adult fecundity.FAW attained the slowest larval development(19.4 days)on sorghum and the fastest(14.1 days)on artificial diet,with larvae attaining 99.6%survival on the latter food item.On rice,FAW larvae attained survival rate of 0.4%and were unable to pupate successfully.Pupation rate and pupal survival varied substantially between artificial diet and live plantlets at different phenological stages.Pupal weight was the highest(0.26 g)on artificial diet and the lowest(0.14 g)on sorghum,while FAW females reached the highest fecundity(699.7 eggs/female)on 2-leaf stage maize.Egg hatching rate equaled 93.6%on 4-or 5-leaf stage maize and 36.6%on artificial diet.FAW intrinsic rate of natural increase and the finite rate of increase varied between larval diets,reflecting how young maize leaves are the most suitable diet.Our findings can help to refine laboratory rearing protocols,devise population forecasting models or guide the deployment of‘area-wide’integrated pest management(IPM)modules in FAW-invaded areas of China and other Asian countries.展开更多
The quality of life is considered as the distributed degree of social resources with significance to the urban residents as a whole. There are three features about the study of the quality of life by means of objectiv...The quality of life is considered as the distributed degree of social resources with significance to the urban residents as a whole. There are three features about the study of the quality of life by means of objective method. First, objective methid is based on the government publication of statistics from which the information of social environment influencing people’s life can be obtained by systematic analysis. Second, as a result of social policy and planning development, the quality of life studied by objective method can provide scieatific basis for regulating and making policy. Third, the objective method emphasize that the improvement of the quality of life mainly depends on the effort from the government so as to set up a coordinatly developed environment of community.On the basis of relevant data from the 1991 Yearbook of Urban Statirtics of China published by Statistics Press of China, and using spss, the quality of urban life in China is evaluated. Seventy four cities are selected from展开更多
This paper studied the sustainable development through a reasonable management of the social, economic and natural environment in a forested mountain area of northeast China. In order to show the local people how to m...This paper studied the sustainable development through a reasonable management of the social, economic and natural environment in a forested mountain area of northeast China. In order to show the local people how to manage their most important forest resource, we analyzed the life-history process of the key species and the influencing factors that were associated with the forest regeneration and sustainability. Pollination and fertilization were mainly affected by weather conditions. Light intensity under the forest canopy was the key factor that controlled seedlings growth and saplings survival. Periodic seeds setting caused the fluctuations of rodents and other related animals in the food chain. Squirrels played a very important role in the forest regeneration, theses animals were the absolutely indispensable components of the forest ecosystem. How to understand the co-evolutionary relationships among species in the forest ecosystems was very important for the conservation of biodiversity and maintenance of ecosystem itegrity. In conservation of the natural resources, we studied the social and economic environment of the forested mountain area. It is very hard to effectively protect the forest resources and maintain the normal life of the local people under the regime of the “unified administration and enterprise system”. Reforms are needed both in administrative institutions and in enterprise management. In the end, this paper proposed that we should not only protect the trees, the related animals, the ecological habitats, and the whole forest ecosystems, but also consider the human activities and their basic requirements so as to realize a sustainable development in the forested mountain areas.展开更多
Two opposing intellectual traditions and their contem-porary developments regarding the relations among population, available resources, and quality of life as reflected in economic growth are reviewed. What is at iss...Two opposing intellectual traditions and their contem-porary developments regarding the relations among population, available resources, and quality of life as reflected in economic growth are reviewed. What is at issue is whether population growth is detrimental to or beneficial for economic development. Neither of the extreme views gives a complete picture of the interplay among population, resources, and quality of life. Following previous literature on the topic, this paper establishes a more balanced approach that considers the function linking population and quality of life not constant but variable and regards the limitedness of resources as not absolute but relative to regions and societies. The proposed approach is more flexible in better explaining the relation between population and economic growth. China is examined as a case in point to shed light on the interaction of population growth, economic development, and available resources, and its recent post-economic reform experiences showcase the appropriateness of the synthetic approach.展开更多
The aim of this research was to value, using a multiple regression model, the role of knowledge to guarantee the development in rural areas of European Union countries over 10 years. The main question was to find out ...The aim of this research was to value, using a multiple regression model, the role of knowledge to guarantee the development in rural areas of European Union countries over 10 years. The main question was to find out relationships among some variable, as the percentage of national Gross Domestic Product (GDP) used to improve the high training, and rural development in terms of agricultural labour units. The results underlined in 2001 as an high value of rural development, in terms of working force in agriculture, was identified in some countries of European Union characterised by a low value both in high training investments and also by a low value of Human Development Index, according to the definition of The Economist. The results in 2010 pointed out an inverse correlation among the dependent variable development in rural areas and the independent variables per capita GDP and national expenditure in advanced training, in percentage of national GDP. The learning by doing and by using, the introduction of advanced training in agriculture, using Long Life Learning measures of European Union, are important to improve the development of European rural areas but, sometimes, these actions are not perceived as something of useful.展开更多
The knowledge of a product's life cycle is the first step on the search of sustainable development. The life cycle assessment (LCA) is an important method because it allows an environment accounting, where the extr...The knowledge of a product's life cycle is the first step on the search of sustainable development. The life cycle assessment (LCA) is an important method because it allows an environment accounting, where the extraction of natural resources and energy of the nature are considered and the "returns" to the same one and allows in evaluating relative potential the environment impacts generated. The present work had as objective to make an analysis of material and energy flows of the life cycle of three types of packaging for soft drinks: glass bottles of 390 mL, aluminum cans of 350 mL, and bottles of PET of 2,000 mL. The study considered processes since the extraction of raw materials for production of the packaging until the stages of recycling, after the consumption of the soft drink. For the research, an inventory analysis followed the LCA methodology. The main critical points of generation of negative environmental impact during the life cycle of each packaging had been the identified and quantified data in this study. The consumption of natural resources like water and other raw materials and energy, the generation of atmospheric emissions, solid wastes and wastewaters had been the analyzed categories. The results showed that, in accordance with the scenes and defined variables, the most important conclusion was that the bottle of glass presented a less favorable scene to the environment in comparison with other packaging.展开更多
To categorize the nations to reflect the development status, to date, there are many conceptual frameworks. The Human Development index (HDI) that is published by the United Nations Development Programme is widely acc...To categorize the nations to reflect the development status, to date, there are many conceptual frameworks. The Human Development index (HDI) that is published by the United Nations Development Programme is widely accepted and practiced by many people such as academicians, politicians, and donor organizations. However, though the development of HDI has gone through many revisions since its formulation in 1990, even the current version of the index formulation published in 2016 needs research to better understand and to gap-fill the knowledge base that can enhance the index formulation to facilitate the direction of attention such as release of funds. Therefore, in this paper, based on principal component analysis and K-means clustering algorithm, the data that reflect the measures of life expectancy index (LEI), education index (EI), and income index (II) are analyzed to categorize and to rank the member states of the UN using R statistical software package, an open source extensible programming language for statistical computing and graphics. The outcome of the study shows that the proportion of total eigen value (i.e., proportion of total variance) explained by PCA-1 (i.e., first principal component) accounts for more than 85% of the total variation. Moreover, the proportion of total eigen value explained by PCA-1 increases with time (i.e., yearly) though the amount of increase with time is not significant. However, the proportions of total eigen value explained by PCA-2 and PCA-3 decrease with time. Therefore, the loss of information in choosing PCA-1 to represent the chosen explanatory variables (i.e., LEI, EI, and II) may diminish with time if the trend of increasing pattern of proportion of total eigen value explained by PCA-1 with time continues in the future as well. On the other hand, the correlation between EI and PCA-1 increases with time although the magnitude of increase is not that significant. This same trend is observed in II as well. However, in contrast to these observations, the correlation between PCA-1 and LEI decreases with time. These findings imply that the contributions of EI and II to PCA-1 increase with time, but the contribution of LEI to PCA-1 decreases with time. On top of these, as per Hopkins statistic, the clusterability of the information conveyed by PCA-1 alone is far better than the clusterability of the information conveyed by PCA scores (i.e., PCA-1, PCA-2, and PCA-3) and the explanatory variables. Therefore, choosing PCA-1 to represent the chosen explanatory variables is becoming more concrete.展开更多
In response to the Beautiful China development strategy,in accordance with the"applicable,economical,green and beautiful"architectural policy of the new era,green buildings have been continuously optimized a...In response to the Beautiful China development strategy,in accordance with the"applicable,economical,green and beautiful"architectural policy of the new era,green buildings have been continuously optimized and popularized.Based on the life cycle theory,from the multi-dimensional perspectives of policy,building materials,construction,design,evaluation standards,operation,etc.,this paper studied the implementation path and development trend of green buildings.It discussed the main implementation paths and restrictive factors of green buildings,and provided solutions and development directions.It mainly elaborated the influencing factors and development direction of green buildings,in order to provide a documentary support for the development of green building industry,and provide a certain reference for the ecological civilization construction of beautiful China.展开更多
Life sciences urban developments are a relatively recent phenomenon, and follow the emergence of knowledge based urban developments as a potential driver of urban regeneration and local economic growth. The role of th...Life sciences urban developments are a relatively recent phenomenon, and follow the emergence of knowledge based urban developments as a potential driver of urban regeneration and local economic growth. The role of these new centres in transforming the inner cities of some of the UK's larger conurbations is examined and the key planning issues are discussed. The article concludes that the key principles of urban planning and control must still apply in shaping the role these new developments have in the UK's evolving urban landscape.展开更多
In this paper, we conduct research on the development trend of urbanization of the rural migrant workers from the perspectives of health and life stress. According to the theory of modern sociological about community,...In this paper, we conduct research on the development trend of urbanization of the rural migrant workers from the perspectives of health and life stress. According to the theory of modern sociological about community, the migrant worker and city people’s relations belongs to typical in community’s relations with the outside community, among them not only isolates and repels psychologically mutually, but also has the direct conflicts of interest. This not only causes the migrant worker to suffer the prejudice and discrimination of city people, is hard to be a part of the city life, but also causes repellency urban institutional arrangements to disintegrate to a certain extent difficultly while the migrant worker is hard to enter in the urban system. Under this basis, this paper proposes the health and life stress assisted development trend of urbanization of the rural migrant workers basic research, the idea is new and innovative, in the later time we will apply it more.展开更多
In this paper, several critical issues related to Chinese high-speed rails (CHSR) are analyzed, investigated and discussed, including development background, reasons for high ticket fare, some typical factors that inf...In this paper, several critical issues related to Chinese high-speed rails (CHSR) are analyzed, investigated and discussed, including development background, reasons for high ticket fare, some typical factors that influence the environmental life-cycle assessment, time and cost comparison of typical door-to-door travel routes between different transport modes and complementary strategies among different transport modes. First, the results show that the expanding high-speed rail network increased the pressure on the country's roads in the 2010 spring festival rush period due to the high ticket fare of CHSR. Second, due to lower than expected ridership because of the high ticket price and limited demand in less developed areas, some Chinese CHSR projects have become economically unsustainable. Third, without sufficient ridership and service life, the utilization of HSR was unable to show any advantages in the environmental impact compared with the other transport modes. In addition, the impact of shock from CHSR on Chinese domestic civil airlines is evident when the travel distance is below 1050 km. The key objective of the investigation is to enhance our understanding of the development and operation of Chinese high-speed rail. One of the key contributions of the current paper is the presented suggestions for complementary strategies between different transport modes to make full use of Chinese transportation resources to promote low carbon economy.展开更多
文摘AIM:To compare and analyse the diagnostic efficacy of the College of Optometrists Vision Development Quality of Life Questionnaire(COVD-QOL)and the Convergence Insufficiency Symptom Survey(CISS)in detecting convergence insufficiency and to compare their diagnostic value in clinical applications.METHODS:Using the diagnostic test method,62 adult patients with convergence insufficiency(age:24.74±3.75y)and 62 normal participants(age:23.61±3.13y)who visited the Optometry Clinic of West China Hospital of Sichuan University from April 2021 to January 2023 were included.All subjects completed the CISS and COVD-QOL.Statistical analysis of the sensitivity and specificity of the CISS and COVD-QOL and comparison and joint experimental analysis of their diagnostic efficacy were performed.RESULTS:The sensitivity of the CISS and COVD-QOL for convergence insufficiency was 64.5%and 71.0%,respectively,while the specificity was 96.8%and 67.7%,respectively.Compared to the CISS alone,the combination of the CISS and COVD-QOL demonstrated lower sensitivity and specificity.The areas under the receiver operating characteristic curve of CISS,COVD-QOL and CISS combined with COVD-QOL were 0.806,0.694 and 0.782,respectively.CONCLUSION:Considering the low sensitivity of the CISS and the low specificity of the COVD-QOL,it is recommended to supplement these questionnaires with other screening tests for the detection of convergence insufficiency.
基金partially supported by the Natural Science Foundation of Zhejiang Province(Award number:D21C170001)the National Natural Science Foundation of China(Award number:31973000)。
文摘Background Four-chambered stomach including the forestomachs(rumen,reticulum,and omasum)and abomasum allows ruminants convert plant fiber into high-quality animal products.The early development of this four-chambered stomach is crucial for the health and well-being of young ruminants,especially the immune development.However,the dynamics of immune development are poorly understood.Results We investigated the early gene expression patterns across the four-chambered stomach in Hu sheep,at 5,10,15,and 25 days of age.We found that forestomachs share similar gene expression patterns,all four stomachs underwent widespread activation of both innate and adaptive immune responses from d 5 to 25,whereas the metabolic function were significantly downregulated with age.We constructed a cell landscape of the four-chambered stomach using single-cell sequencing.Integrating transcriptomic and single-cell transcriptomic analyses revealed that the immune-associated module hub genes were highly expressed in T cells,monocytes and macrophages,as well as the defense-associated module hub genes were highly expressed in endothelial cells in the four-stomach tissues.Moreover,the non-immune cells such as epithelial cells play key roles in immune maturation.Cell communication analysis predicted that in addition to immune cells,non-immune cells recruit immune cells through macrophage migration inhibitory factor signaling in the forestomachs.Conclusions Our results demonstrate that the immune and defense responses of four stomachs are quickly developing with age in lamb's early life.We also identified the gene expression patterns and functional cells associated with immune development.Additionally,we identified some key receptors and signaling involved in immune regulation.These results help to understand the early life immune development at single-cell resolution,which has implications to develop nutritional manipulation and health management strategies based on specific targets including key receptors and signaling pathways.
文摘In this paper, the Life Cycle of Urban Development was firstly analyzed, and the phases of Life Cycle Assessment applied to Urban Development (ULCA) were described. As a case study, ULCA was applied in the environmental impact assessment of the land readjustment project of Hyogo District of Saga, Japan. In addition, mitigation proposals for reducing CO2 were also presented and the relevant environmental ef-fects were simulated.
文摘Social achievement in the world is dependent to a great extent on the development of mineral resources. A changing pattern of the Life Cycle in mineral consumption, with a general pattern of introduction, growth, stability and decline, is seen as a determinant factor not only to the transformation of industrial structure, but also to the infrastructural construction, industrial location, the spatial organization of urban development as well as regional environmental protection.
文摘Quality of Life (QOL) is a multiphase conception, including physical, mental and social factors, and can overall reflect health status of the human. At present, QOL has become a relevant measure of efficacy of treatment in clinical trials. Its use is spreading, and its importance is growing as a valid indicator of whether or not a medical treatment is
文摘China is the most populous country in the world.The total Population on the mainland of China has in-creased from 540 million in 1949 to 1.18 billion by the end of 1993.China adopted a population policy by namc of"controlling population growth and im-proving the quality of the human resources',which has been deeply rooted in the hearts of the Chinese pcoplc.The overw helming majority of the Chinese people have recognized the necessity for implementing the family planning programme not only for the sustained devel-opment of the country,but also for the benefits of their own familie cs.
文摘The research on the tire industry cluster based on life cycle theory can be carried out by a four stage periods,namely initial period,growth period,maturity period,and recession period.This paper analyzes on the possible risks taken in each life cycle period as well as proposes corresponding suggestions to strengthen the research by looking into the conditions and factors of the continuous sustainable development process in a tire industry.
基金funded by the project entitled Technical Countermeasures for the Quantitative Characterization and Adjustment of Residual Gas in Tight Sandstone Gas Reservoirs of the Daniudi Gas Field(P20065-1)organized by the Science&Technology R&D Department of Sinopec.
文摘Based on an analysis of the limitations of conventional production component methods for natural gas development planning,this study proposes a new one that uses life cycle models for the trend fitting and prediction of production.In this new method,the annual production of old and new wells is predicted by year first and then is summed up to yield the production for the planning period.It shows that the changes in the production of old wells in old blocks can be fitted and predicted using the vapor pressure model(VPM),with precision of 80%e95%,which is 6.6%e13.2%higher than that of other life cycle models.Furthermore,a new production prediction process and method for new wells have been established based on this life cycle model to predict the production of medium-to-shallow gas reservoirs in western Sichuan Basin,with predication error of production rate in 2021 and 2022 being 6%and 3%respectively.The new method can be used to guide the medium-and long-term planning or annual scheme preparation for gas development.It is also applicable to planning for large single gas blocks that require continuous infill drilling and adjustment to improve gas recovery.
基金financially supported by China Postdoctoral Science Foundationthe National Natural Science Foundation of China(Grant No.51705132)+1 种基金the Natural Science Project of Henan Provincial Department of Science and Technology(Grant No.222102220088)the Natural Science Project of Henan Provincial Department of Education(Grant No.21A460006)。
文摘With the development of modern industry and ever more complex structural loads,the possibility of fatigue failure is increasing.Fatigue analysis can be used to evaluate the service life of components and reduce the probability of accidents.Therefore,the development and application of fatigue-analysis technology have important research significance.This paper collects information from a wide field of literature and summarizes the current status of fatigue-analysis research.It covers related theoretical knowledge,fatigue-life prediction methods,and fatigue design methods and their application scenarios,and it summarizes the challenges and research hotspots in the field.On the basis of this examination,future development directions of fatigue-life prediction methods are proposed.The conclusions will have a certain guiding role in the development of fatigue-analysis methods.
基金supported by the earmarked fund for China Agriculture Research System(CARS-15-19)the Central Public-interest Scientific Institution Basal Research Fund,China(Y2019YJ06)。
文摘In December 11,2018,the fall armyworm(FAW),Spodoptera frugiperda invaded China and has since impacted local maize,sorghum and other crops.Here,we draw on laboratory experiments to show how different host crops(i.e.,maize,sorghum,wheat and rice)and artificial diet affect larval growth and adult reproduction of one local FAW strain.Larval diet affected development duration,pupation rate,survival and emergence rate of pupae,and S.frugiperda adult fecundity.FAW attained the slowest larval development(19.4 days)on sorghum and the fastest(14.1 days)on artificial diet,with larvae attaining 99.6%survival on the latter food item.On rice,FAW larvae attained survival rate of 0.4%and were unable to pupate successfully.Pupation rate and pupal survival varied substantially between artificial diet and live plantlets at different phenological stages.Pupal weight was the highest(0.26 g)on artificial diet and the lowest(0.14 g)on sorghum,while FAW females reached the highest fecundity(699.7 eggs/female)on 2-leaf stage maize.Egg hatching rate equaled 93.6%on 4-or 5-leaf stage maize and 36.6%on artificial diet.FAW intrinsic rate of natural increase and the finite rate of increase varied between larval diets,reflecting how young maize leaves are the most suitable diet.Our findings can help to refine laboratory rearing protocols,devise population forecasting models or guide the deployment of‘area-wide’integrated pest management(IPM)modules in FAW-invaded areas of China and other Asian countries.
文摘The quality of life is considered as the distributed degree of social resources with significance to the urban residents as a whole. There are three features about the study of the quality of life by means of objective method. First, objective methid is based on the government publication of statistics from which the information of social environment influencing people’s life can be obtained by systematic analysis. Second, as a result of social policy and planning development, the quality of life studied by objective method can provide scieatific basis for regulating and making policy. Third, the objective method emphasize that the improvement of the quality of life mainly depends on the effort from the government so as to set up a coordinatly developed environment of community.On the basis of relevant data from the 1991 Yearbook of Urban Statirtics of China published by Statistics Press of China, and using spss, the quality of urban life in China is evaluated. Seventy four cities are selected from
文摘This paper studied the sustainable development through a reasonable management of the social, economic and natural environment in a forested mountain area of northeast China. In order to show the local people how to manage their most important forest resource, we analyzed the life-history process of the key species and the influencing factors that were associated with the forest regeneration and sustainability. Pollination and fertilization were mainly affected by weather conditions. Light intensity under the forest canopy was the key factor that controlled seedlings growth and saplings survival. Periodic seeds setting caused the fluctuations of rodents and other related animals in the food chain. Squirrels played a very important role in the forest regeneration, theses animals were the absolutely indispensable components of the forest ecosystem. How to understand the co-evolutionary relationships among species in the forest ecosystems was very important for the conservation of biodiversity and maintenance of ecosystem itegrity. In conservation of the natural resources, we studied the social and economic environment of the forested mountain area. It is very hard to effectively protect the forest resources and maintain the normal life of the local people under the regime of the “unified administration and enterprise system”. Reforms are needed both in administrative institutions and in enterprise management. In the end, this paper proposed that we should not only protect the trees, the related animals, the ecological habitats, and the whole forest ecosystems, but also consider the human activities and their basic requirements so as to realize a sustainable development in the forested mountain areas.
文摘Two opposing intellectual traditions and their contem-porary developments regarding the relations among population, available resources, and quality of life as reflected in economic growth are reviewed. What is at issue is whether population growth is detrimental to or beneficial for economic development. Neither of the extreme views gives a complete picture of the interplay among population, resources, and quality of life. Following previous literature on the topic, this paper establishes a more balanced approach that considers the function linking population and quality of life not constant but variable and regards the limitedness of resources as not absolute but relative to regions and societies. The proposed approach is more flexible in better explaining the relation between population and economic growth. China is examined as a case in point to shed light on the interaction of population growth, economic development, and available resources, and its recent post-economic reform experiences showcase the appropriateness of the synthetic approach.
文摘The aim of this research was to value, using a multiple regression model, the role of knowledge to guarantee the development in rural areas of European Union countries over 10 years. The main question was to find out relationships among some variable, as the percentage of national Gross Domestic Product (GDP) used to improve the high training, and rural development in terms of agricultural labour units. The results underlined in 2001 as an high value of rural development, in terms of working force in agriculture, was identified in some countries of European Union characterised by a low value both in high training investments and also by a low value of Human Development Index, according to the definition of The Economist. The results in 2010 pointed out an inverse correlation among the dependent variable development in rural areas and the independent variables per capita GDP and national expenditure in advanced training, in percentage of national GDP. The learning by doing and by using, the introduction of advanced training in agriculture, using Long Life Learning measures of European Union, are important to improve the development of European rural areas but, sometimes, these actions are not perceived as something of useful.
文摘The knowledge of a product's life cycle is the first step on the search of sustainable development. The life cycle assessment (LCA) is an important method because it allows an environment accounting, where the extraction of natural resources and energy of the nature are considered and the "returns" to the same one and allows in evaluating relative potential the environment impacts generated. The present work had as objective to make an analysis of material and energy flows of the life cycle of three types of packaging for soft drinks: glass bottles of 390 mL, aluminum cans of 350 mL, and bottles of PET of 2,000 mL. The study considered processes since the extraction of raw materials for production of the packaging until the stages of recycling, after the consumption of the soft drink. For the research, an inventory analysis followed the LCA methodology. The main critical points of generation of negative environmental impact during the life cycle of each packaging had been the identified and quantified data in this study. The consumption of natural resources like water and other raw materials and energy, the generation of atmospheric emissions, solid wastes and wastewaters had been the analyzed categories. The results showed that, in accordance with the scenes and defined variables, the most important conclusion was that the bottle of glass presented a less favorable scene to the environment in comparison with other packaging.
文摘To categorize the nations to reflect the development status, to date, there are many conceptual frameworks. The Human Development index (HDI) that is published by the United Nations Development Programme is widely accepted and practiced by many people such as academicians, politicians, and donor organizations. However, though the development of HDI has gone through many revisions since its formulation in 1990, even the current version of the index formulation published in 2016 needs research to better understand and to gap-fill the knowledge base that can enhance the index formulation to facilitate the direction of attention such as release of funds. Therefore, in this paper, based on principal component analysis and K-means clustering algorithm, the data that reflect the measures of life expectancy index (LEI), education index (EI), and income index (II) are analyzed to categorize and to rank the member states of the UN using R statistical software package, an open source extensible programming language for statistical computing and graphics. The outcome of the study shows that the proportion of total eigen value (i.e., proportion of total variance) explained by PCA-1 (i.e., first principal component) accounts for more than 85% of the total variation. Moreover, the proportion of total eigen value explained by PCA-1 increases with time (i.e., yearly) though the amount of increase with time is not significant. However, the proportions of total eigen value explained by PCA-2 and PCA-3 decrease with time. Therefore, the loss of information in choosing PCA-1 to represent the chosen explanatory variables (i.e., LEI, EI, and II) may diminish with time if the trend of increasing pattern of proportion of total eigen value explained by PCA-1 with time continues in the future as well. On the other hand, the correlation between EI and PCA-1 increases with time although the magnitude of increase is not that significant. This same trend is observed in II as well. However, in contrast to these observations, the correlation between PCA-1 and LEI decreases with time. These findings imply that the contributions of EI and II to PCA-1 increase with time, but the contribution of LEI to PCA-1 decreases with time. On top of these, as per Hopkins statistic, the clusterability of the information conveyed by PCA-1 alone is far better than the clusterability of the information conveyed by PCA scores (i.e., PCA-1, PCA-2, and PCA-3) and the explanatory variables. Therefore, choosing PCA-1 to represent the chosen explanatory variables is becoming more concrete.
文摘In response to the Beautiful China development strategy,in accordance with the"applicable,economical,green and beautiful"architectural policy of the new era,green buildings have been continuously optimized and popularized.Based on the life cycle theory,from the multi-dimensional perspectives of policy,building materials,construction,design,evaluation standards,operation,etc.,this paper studied the implementation path and development trend of green buildings.It discussed the main implementation paths and restrictive factors of green buildings,and provided solutions and development directions.It mainly elaborated the influencing factors and development direction of green buildings,in order to provide a documentary support for the development of green building industry,and provide a certain reference for the ecological civilization construction of beautiful China.
文摘Life sciences urban developments are a relatively recent phenomenon, and follow the emergence of knowledge based urban developments as a potential driver of urban regeneration and local economic growth. The role of these new centres in transforming the inner cities of some of the UK's larger conurbations is examined and the key planning issues are discussed. The article concludes that the key principles of urban planning and control must still apply in shaping the role these new developments have in the UK's evolving urban landscape.
文摘In this paper, we conduct research on the development trend of urbanization of the rural migrant workers from the perspectives of health and life stress. According to the theory of modern sociological about community, the migrant worker and city people’s relations belongs to typical in community’s relations with the outside community, among them not only isolates and repels psychologically mutually, but also has the direct conflicts of interest. This not only causes the migrant worker to suffer the prejudice and discrimination of city people, is hard to be a part of the city life, but also causes repellency urban institutional arrangements to disintegrate to a certain extent difficultly while the migrant worker is hard to enter in the urban system. Under this basis, this paper proposes the health and life stress assisted development trend of urbanization of the rural migrant workers basic research, the idea is new and innovative, in the later time we will apply it more.
文摘In this paper, several critical issues related to Chinese high-speed rails (CHSR) are analyzed, investigated and discussed, including development background, reasons for high ticket fare, some typical factors that influence the environmental life-cycle assessment, time and cost comparison of typical door-to-door travel routes between different transport modes and complementary strategies among different transport modes. First, the results show that the expanding high-speed rail network increased the pressure on the country's roads in the 2010 spring festival rush period due to the high ticket fare of CHSR. Second, due to lower than expected ridership because of the high ticket price and limited demand in less developed areas, some Chinese CHSR projects have become economically unsustainable. Third, without sufficient ridership and service life, the utilization of HSR was unable to show any advantages in the environmental impact compared with the other transport modes. In addition, the impact of shock from CHSR on Chinese domestic civil airlines is evident when the travel distance is below 1050 km. The key objective of the investigation is to enhance our understanding of the development and operation of Chinese high-speed rail. One of the key contributions of the current paper is the presented suggestions for complementary strategies between different transport modes to make full use of Chinese transportation resources to promote low carbon economy.