[Objective] The objective of this paper was to study the simulation and implementation of structure and growth visualization system of artificial mixed stand. [Method] The mixed stand structure visualization model and...[Objective] The objective of this paper was to study the simulation and implementation of structure and growth visualization system of artificial mixed stand. [Method] The mixed stand structure visualization model and growth visualization model were built on the base of the characteristics of mixed stand structure and the relationship between growth and environment; and the C# language and MOGRE graphics engine were used to establish the mixed stand structure and growth visualization system. [Result] The mixed stand structure visualization model and growth visualization model were built, as well as the mixed stand structure and growth visualization system. [Conclusion] This paper realized the visualization simulation of the mixed stand structure and growth.展开更多
Detailed studies on population structure and regeneration ecology ofllex khasiana were carried out at five representative natural populations i.e. Mylliem (Population - I), Upper Shillong (Population - II), Shillo...Detailed studies on population structure and regeneration ecology ofllex khasiana were carried out at five representative natural populations i.e. Mylliem (Population - I), Upper Shillong (Population - II), Shillong Peak (Population -III), Laitkor (Population - IV) and Nongpiyur (Population - V) to probe into the responsible affecting factors for its population structure and regeneration ability in these populations. Experimental observation under three controlled light conditions (full sunlight (100%), intermediate sunlight (50%) and low sunlight (30%)) showed that the growth status and survival rates of seedlings under intermediate and low light were better than those under the high light condition. The density-diameter distribution in population of adult trees (〉Scm dbh) exhibited a typical character of a regenerating population. A higher seedling mortality rate in natural populations of I. khasiana was most probably due to increase in light intensity following vegetation destruction and other anthropogenic disturbances that cause opening of forest canopy. The findings of the present study would be of immense value in formulating appropriate conservation measures for the species.展开更多
Impact of anthropogenic disturbance on species diversity and vegetation structure of a lowland tropical rainforest was studied in the foothills of Eastern Himalaya, India. Tree species richness,density, basal area and...Impact of anthropogenic disturbance on species diversity and vegetation structure of a lowland tropical rainforest was studied in the foothills of Eastern Himalaya, India. Tree species richness,density, basal area and the diversity indices were found significantly(P<0.05) decreased with the increasing level of disturbances whereas, shrub density, basal area and herb density significantly increased with increasing disturbance level. In case of shrubs, Simpson's dominance index significantly(P<0.007) increased along the disturbance gradient,whereas Pielou's evenness index significantly(P<0.005) decreased with an increasing level of disturbance. Shannon-Weiner diversity index for herbs significantly(P<0.016) increased with increasing disturbance whereas, Simpson's dominance index was significantly(P<0.013) declined along the disturbance gradient. Results revealed that10-50 cm dbh classes constituted the highest stem density, and highest basal area was recorded in the >100 cm dbh class in all three sites. Density of the matured trees decreased with increasing DBH whereas, tree basal area tended to increase with increasing DBH in all three sites. Tree species richness was highest in the lower DBH classes.62.07% of the total tree species regenerated in the largely undisturbed site followed by 50% in the mildly disturbed and 26.32% in the highly disturbed site.The overall regeneration condition was found to be good in the largely undisturbed site. Mildly disturbed site exhibited fair regeneration and so was in the highly disturbed site. Discernable variations in species composition, diversity, regeneration and tree population structure revealed the impact of anthropogenic disturbances on rainforest vegetation dynamics. Higher degree of disturbance was furtherly found not only affecting species diversity but also promoting the growth of invasive weed species.Dominance of Hydnocarpus kurzii and Crypteronia paniculata in the highly disturbed site also indicated that these less-valued timber species may benefit from the vegetation mosaic produced by the disturbance; so differences in abundance of these species may be useful for bio-indication. Furthermore,present study suggests the need of adequate biodiversity conservation measures and adaptation of sustainable forest management approaches in disturbed areas of lowland tropical rainforest in the foothills of eastern Himalaya, India.展开更多
Spinning gait is valuable for quadruped robot,which can be used to avoid obstacles quickly for robot walking in unstructured environment. A kind of bionic flexible body is presented for quadruped robot to perform the ...Spinning gait is valuable for quadruped robot,which can be used to avoid obstacles quickly for robot walking in unstructured environment. A kind of bionic flexible body is presented for quadruped robot to perform the spinning gait. The spinning gait can be achieved by coordinated movement of body laterally bending and legs swing,which can improve the mobility of robot walking in the unstructured environments. The coordinated movement relationship between the body and the leg mechanism is presented. The stability of quadruped robot with spinning gait is analyzed based on the center of gravity( COG) projection method. The effect of different body bending angle on the stability of quadruped robot with spinning gait is mainly studied. For the quadruped robot walking with spinning gait,during one spinning gait cycle,the supporting polygon and the trajectory of COG projection point under different body bending angle are calculated. Finally,the stability margin of quadruped robot with spinning gait under different body bending angle is determined,which can be used to evaluate reasonableness of spinning gait parameters.展开更多
Based on the theory of geo-economy,under the new situation of global economy,information network and China’s entry into WTO,also with the holding of APEC (in 2001) and the International Exposition in the near future,...Based on the theory of geo-economy,under the new situation of global economy,information network and China’s entry into WTO,also with the holding of APEC (in 2001) and the International Exposition in the near future,the Changjiang (Yangtze) River Delta is striding toward the spectacular international multi-polar situation and becomes one of core regions with high-speed development. Facing the ocean and world all along,leading the progressive tides of the age and scintillating the splendor of the nation,she does advance with time. Through a long period of irrigation projects construction and intensive operation of lands in previous agricultural society,the artificial wetland ecosystem with a positive cycle had ever been formed in this region. At present,environmental pollution and urban expansion resulted from post-industrialization are being rectified. The delta will be the paradigm of industrial and agricultural modernization along the sustainable development road. With the rapid development of urbanization,she has been one of the regions with the highest density population and high urbanization level. Taking the Changjiang River estuary and the Hangzhou Bay as two parts,she is continuously strengthening and adjusting her interior structure,expanding mothball space and constructing the oriental modern "logistics center" to link the whole world. The butterfly-style urban system of the Changjiang River Delta is flying,probably engendering earthshaking "butterfly effect".展开更多
This paper examines the transition of growth stage China is about to experience and the main conclusions are as follows: (1) Phase Ⅰ of economic growth driven by investment and export is losing the momentum of eff...This paper examines the transition of growth stage China is about to experience and the main conclusions are as follows: (1) Phase Ⅰ of economic growth driven by investment and export is losing the momentum of efficiency enhancement through intervention and the growth stage of efficiency enhancement through structural adjustment is coming to an end. Urbanization and the development of service sector will inaugurate Phase Ⅱ of stable economic growth characterized by structural optimization through efficiency enhancement; (2) Three leading factors promoting the transition from Phase Ⅰ to Phase Ⅱ include: demographic changes and the emergence of workforce turning point, the reversion of factor elasticity parameters of long-term growth function, and service-oriented economic structure; (3) Developed provinces and municipalities in east China have already entered into the channel of economic deceleration. With increasing urbanization rate, accelerating service-oriented structure and declining demographic dividend after 2016, China's economic slowdown would be inevitable if labor productivity fails to improve.展开更多
The problem is what plagued our society since the last decade as far as human resource allocation concerned. HR theory explains the phenomenon of Graduates Employment Dilemma and found a way to solve this problem, fro...The problem is what plagued our society since the last decade as far as human resource allocation concerned. HR theory explains the phenomenon of Graduates Employment Dilemma and found a way to solve this problem, from theory and solution perspective. Maslow' s hierarchy of needs has some effect on students' employment. University Students should accelerate the transformation of the concept of employment, to accelerate the pace of structural adjustment, the implementation of the industrialization of education; Guide and encourage students to find a job by using two-factor theory; Make sure college students can stay in a dominant position in the intellectual property of human resource, in order to avoid structural unemployment, so as to make the most use of the students as valuable and effective human resources.展开更多
The feasibility of city living with nature as a way to restore the balance between human uses and natural processes is the focus of this paper about the city of Maringa in Southern Brazil. This urban form, a planned n...The feasibility of city living with nature as a way to restore the balance between human uses and natural processes is the focus of this paper about the city of Maringa in Southern Brazil. This urban form, a planned new town founded in 1947 upon a previous, comprehensive British land-development scheme, originally offered a friendly interaction between urban settlement and nature. Hence, this paper outlines how open spaces can be enhanced as an ecological structure, bringing parks, squares, gardens and urban farming into a productive system, both for nature's and for people's sakes. Following a morphological study, the proposed ecological structure will maintain ecological processes within the urban grid and help to preserve historical and social values, by linking a wide variety of natural and restored ecosystems and landscape features. The adoption of this kind of ecological planning will certainly result in an increase of the urban landscape quality, changing actual planning paradigm and preventing the city from environmental quality decrease.展开更多
Ecosystem valuation can serve as a basis of scientific support for decision-making. So far, the most popular methods for ecosystem valuation are ecosystem service valuation (ESV), which is based on the utility of ec...Ecosystem valuation can serve as a basis of scientific support for decision-making. So far, the most popular methods for ecosystem valuation are ecosystem service valuation (ESV), which is based on the utility of ecosystem to human beings rather than on the objective value of the ecosystem. After more than 10 years' application, it has been found that all losses of ESV were about 10% of the benefits of human activities. In this paper, the ecosystem intrinsic value (EIV) is defined. EIV is an objective value that emerges from the existence, structures, functions and processes of ecosystem, but independent with man, man's will and preferences. The valuating approach and methods used for EIV were developed by using energy approach and the methods of emergy analysis and eco-exergy analysis. The EIV calculated by emergy from the substance, energy and information of ecosystem and by eco-exergy from the structure and function of ecosystem represents the existent value and the externally working capacity of ecosystem, respectively. The approach and methods of EIV evaluation were applied to Xiamen Bay, China. The results showed that the marine EIV in Xiamen Bay was 209 billion RMB, including 116 billion RMB of emergy and 92.4 billion RMB of eco-exergy in 2010, nearly 30 times of ESV and 8.5 times of the GDP of Xiamen marine industry in 2010. The EIV in unit area of Xiarnen Bay is more than 10 times higher than the average global ESV in estuaries. It implied a potential undervaluation to ecosystem value by ESV calculation, which may mislead decisions-making processes.展开更多
Sustainable development indicators, aim to measure sustainable development over longer periods of time. The sustainable development indicators are grouped into 10 subject categories: socioeconomic development, sustai...Sustainable development indicators, aim to measure sustainable development over longer periods of time. The sustainable development indicators are grouped into 10 subject categories: socioeconomic development, sustainable consumption and production, social inclusion, demographic changes, public health, climate change and energy, sustainable transport, natural resources, global partnership and finally good governance. In this paper, the authors examined a number of researches and compared the methods they used in order to determine the advantages and disadvantages of each method. The methods used a large number of different indicators. The comparison of the indicators could be made through mathematical models and also through theoretical approach.展开更多
The term "forgotten city" was mentioned by researchers to denominate some colonial Brazilian settlements and cities which seem to have the same characteristics that demonstrate they were hidden along the years and t...The term "forgotten city" was mentioned by researchers to denominate some colonial Brazilian settlements and cities which seem to have the same characteristics that demonstrate they were hidden along the years and that have the same atmosphere as they used to in their past life, i.e., they have the same traditional type of urban configuration produced at the origin of the city. This paper brings into discussion this character of this city, using as an example the city of Laranjeiras, one of the oldest cities of the State of Sergipe, which had a great and rich trade of sugar, besides significant cultural and political activities, being known as "Brazilian Athens" in the 19th century. Then, Laranjeiras decayed and stopped growing along the 20th century. However, it has had a good perspective to develop again with insertion of new different activities recently. The initial Portuguese planning to villages in Brazil followed specific rules and had a systematic assistance, what discards the myth that many Brazilian cities were born and grown up as a spontaneous form without planning. Studying some factors deeply, as spatial configuration, settlement localization and urban grid, it can be possible to point some recognizable elements which demonstrate that some cities were built to be forgotten. The methodology used for the analysis of Laranjeiras presents many historic, economic and cultural aspects related to the spatial-syntactic studies (Space Syntax Theory), bringing to light some interesting thoughts about urban form and social life.展开更多
Good landing buffering performance can reduce impact and vibration for the bionic locust jumping robot; thus, a landing buffer is important in evaluating the motion performance of the bionic locust robot. In particula...Good landing buffering performance can reduce impact and vibration for the bionic locust jumping robot; thus, a landing buffer is important in evaluating the motion performance of the bionic locust robot. In particular, the legs of the robot are the main structures that realize the buffer; thus, its structure affects buffering performance. Three typical leg structure models are established based on the physiological analysis of the locust leg and research status, namely, bionic leg, multi-constraint leg, and arc legs. Kinematic and force analyses are conducted for these types of legs. Particularly, flexible deformation of leg link is considered in the analysis to describe the movement process accurately. In order to compare the buffering performance of these types of legs quantitatively, the performance indices with maximum buffering distance, the energy absorption capability, and the mechanical property are presented. Based on the performance indices, the structure parameters are analyzed and optimized. The buffering performance of the three leg structures is compared with the comprehensive performance of different structures in each best state. This study offers a quantitative analysis and comparison for different legs of bionic locust jumping robot based on landing buffering performance. Furthermore, a theoretical basis for future research and engineering applications is established.展开更多
Community spirit is the real essence of community. By involvement in community life, people identify with the communities where they live and work. Thanks to its own distinctive history and cultural environment, Chine...Community spirit is the real essence of community. By involvement in community life, people identify with the communities where they live and work. Thanks to its own distinctive history and cultural environment, Chinese society has a community development and social structure quite distinct from that of the West. Social organizations are not fully developed in China, and the government plays a dominant role in community development. Community building in China should cultivate residents' community consciousness, and be centered on specific social problems such as homelessness, unemployment, family care, poverty, etc.展开更多
Archaea,the third domain of life,are interesting organisms to study from the aspects of molecular and evolutionary biology.Archaeal cells have a unicellular ultrastructure without a nucleus,resembling bacterial cells,...Archaea,the third domain of life,are interesting organisms to study from the aspects of molecular and evolutionary biology.Archaeal cells have a unicellular ultrastructure without a nucleus,resembling bacterial cells,but the proteins involved in genetic information processing pathways,including DNA replication,transcription,and translation,share strong similarities with those of Eukaryota.Therefore,archaea provide useful model systems to understand the more complex mechanisms of genetic information processing in eukaryotic cells.Moreover,the hyperthermophilic archaea provide very stable proteins,which are especially useful for the isolation of replisomal multicomplexes,to analyze their structures and functions.This review focuses on the history,current status,and future directions of archaeal DNA replication studies.展开更多
The causes of population differentiation can provide insight into the origins of early barriers to gene flow. Two key drivers of population differentiation are geographic distance and local adaptation to divergent sel...The causes of population differentiation can provide insight into the origins of early barriers to gene flow. Two key drivers of population differentiation are geographic distance and local adaptation to divergent selective environments. When reproductive isolation arises because some populations of a species are under selection to avoid hybridization while others are not, population differentiation and even speciation can result. Spadefoot toad populations Spea multiplicata that are sympatric with a congener have undergone reinforcement. This reinforcement has resulted not only in increased reproductive isolation from the congener, but also in the evolution of reproductive isolation from nearby and distant conspecific allopatric populations. We used multiple approaches to evaluate the contributions of geographic distance and divergent selective environments to population structure across this regional scale in S. multiplicata, based on genotypes from six nuclear microsatellite markers. We compared groups of populations varying in both geographic location and in the presence of a congener. Hierarchical F-statistics and results from cluster analyses and discriminant analyses of principal components all indicate that geographic distance is the stronger contributor to genetic differentiation among S. multiplicata populations at a regional scale. However, we found evidence that adaptation to divergent selective environments also contributes to population structure. Our findings highlight how variation in the balance of evolutionary forces acting across a species' range can lead to variation in the relative contributions of geographic distance and local adaptation to population differentiation across different spatial scales.展开更多
Researchers hope that establishing a notion of proximity using topology will help to clarify the biological processes underlying the evolution of living organisms. The simple model presented here, using RNA shapes, ca...Researchers hope that establishing a notion of proximity using topology will help to clarify the biological processes underlying the evolution of living organisms. The simple model presented here, using RNA shapes, can carry over to more general and complex genotype-phenotype systems. Proximity is an important component of continuity, in both real-world and topological terms. Consequently, phenotype spaces provide an appropriate setting for modeling and investigating continuous and discontinuous evolutionary change.展开更多
基金Supported by the Forestry Industry Public Welfare Project of China(201104028)the National Natural Science Foundation of China(31170590)the Special Fund for Statelevel Public Welfare Scientiic Research Institute of China(IFRIT201103)~~
文摘[Objective] The objective of this paper was to study the simulation and implementation of structure and growth visualization system of artificial mixed stand. [Method] The mixed stand structure visualization model and growth visualization model were built on the base of the characteristics of mixed stand structure and the relationship between growth and environment; and the C# language and MOGRE graphics engine were used to establish the mixed stand structure and growth visualization system. [Result] The mixed stand structure visualization model and growth visualization model were built, as well as the mixed stand structure and growth visualization system. [Conclusion] This paper realized the visualization simulation of the mixed stand structure and growth.
文摘Detailed studies on population structure and regeneration ecology ofllex khasiana were carried out at five representative natural populations i.e. Mylliem (Population - I), Upper Shillong (Population - II), Shillong Peak (Population -III), Laitkor (Population - IV) and Nongpiyur (Population - V) to probe into the responsible affecting factors for its population structure and regeneration ability in these populations. Experimental observation under three controlled light conditions (full sunlight (100%), intermediate sunlight (50%) and low sunlight (30%)) showed that the growth status and survival rates of seedlings under intermediate and low light were better than those under the high light condition. The density-diameter distribution in population of adult trees (〉Scm dbh) exhibited a typical character of a regenerating population. A higher seedling mortality rate in natural populations of I. khasiana was most probably due to increase in light intensity following vegetation destruction and other anthropogenic disturbances that cause opening of forest canopy. The findings of the present study would be of immense value in formulating appropriate conservation measures for the species.
基金Department of Science & Technology, Government of India (GOI), New Delhi (Grant No. DST/ISSTAC/CO2-SR-227/14(G)-AICP-AFOLU-IV)
文摘Impact of anthropogenic disturbance on species diversity and vegetation structure of a lowland tropical rainforest was studied in the foothills of Eastern Himalaya, India. Tree species richness,density, basal area and the diversity indices were found significantly(P<0.05) decreased with the increasing level of disturbances whereas, shrub density, basal area and herb density significantly increased with increasing disturbance level. In case of shrubs, Simpson's dominance index significantly(P<0.007) increased along the disturbance gradient,whereas Pielou's evenness index significantly(P<0.005) decreased with an increasing level of disturbance. Shannon-Weiner diversity index for herbs significantly(P<0.016) increased with increasing disturbance whereas, Simpson's dominance index was significantly(P<0.013) declined along the disturbance gradient. Results revealed that10-50 cm dbh classes constituted the highest stem density, and highest basal area was recorded in the >100 cm dbh class in all three sites. Density of the matured trees decreased with increasing DBH whereas, tree basal area tended to increase with increasing DBH in all three sites. Tree species richness was highest in the lower DBH classes.62.07% of the total tree species regenerated in the largely undisturbed site followed by 50% in the mildly disturbed and 26.32% in the highly disturbed site.The overall regeneration condition was found to be good in the largely undisturbed site. Mildly disturbed site exhibited fair regeneration and so was in the highly disturbed site. Discernable variations in species composition, diversity, regeneration and tree population structure revealed the impact of anthropogenic disturbances on rainforest vegetation dynamics. Higher degree of disturbance was furtherly found not only affecting species diversity but also promoting the growth of invasive weed species.Dominance of Hydnocarpus kurzii and Crypteronia paniculata in the highly disturbed site also indicated that these less-valued timber species may benefit from the vegetation mosaic produced by the disturbance; so differences in abundance of these species may be useful for bio-indication. Furthermore,present study suggests the need of adequate biodiversity conservation measures and adaptation of sustainable forest management approaches in disturbed areas of lowland tropical rainforest in the foothills of eastern Himalaya, India.
基金Supported by the National Natural Science Foundation of China(No.51375289)Shanghai Municipal National Natural Science Foundation of China(No.13ZR1415500)Innovation Fund of Shanghai Education Commission(No.13YZ020)
文摘Spinning gait is valuable for quadruped robot,which can be used to avoid obstacles quickly for robot walking in unstructured environment. A kind of bionic flexible body is presented for quadruped robot to perform the spinning gait. The spinning gait can be achieved by coordinated movement of body laterally bending and legs swing,which can improve the mobility of robot walking in the unstructured environments. The coordinated movement relationship between the body and the leg mechanism is presented. The stability of quadruped robot with spinning gait is analyzed based on the center of gravity( COG) projection method. The effect of different body bending angle on the stability of quadruped robot with spinning gait is mainly studied. For the quadruped robot walking with spinning gait,during one spinning gait cycle,the supporting polygon and the trajectory of COG projection point under different body bending angle are calculated. Finally,the stability margin of quadruped robot with spinning gait under different body bending angle is determined,which can be used to evaluate reasonableness of spinning gait parameters.
文摘Based on the theory of geo-economy,under the new situation of global economy,information network and China’s entry into WTO,also with the holding of APEC (in 2001) and the International Exposition in the near future,the Changjiang (Yangtze) River Delta is striding toward the spectacular international multi-polar situation and becomes one of core regions with high-speed development. Facing the ocean and world all along,leading the progressive tides of the age and scintillating the splendor of the nation,she does advance with time. Through a long period of irrigation projects construction and intensive operation of lands in previous agricultural society,the artificial wetland ecosystem with a positive cycle had ever been formed in this region. At present,environmental pollution and urban expansion resulted from post-industrialization are being rectified. The delta will be the paradigm of industrial and agricultural modernization along the sustainable development road. With the rapid development of urbanization,she has been one of the regions with the highest density population and high urbanization level. Taking the Changjiang River estuary and the Hangzhou Bay as two parts,she is continuously strengthening and adjusting her interior structure,expanding mothball space and constructing the oriental modern "logistics center" to link the whole world. The butterfly-style urban system of the Changjiang River Delta is flying,probably engendering earthshaking "butterfly effect".
文摘This paper examines the transition of growth stage China is about to experience and the main conclusions are as follows: (1) Phase Ⅰ of economic growth driven by investment and export is losing the momentum of efficiency enhancement through intervention and the growth stage of efficiency enhancement through structural adjustment is coming to an end. Urbanization and the development of service sector will inaugurate Phase Ⅱ of stable economic growth characterized by structural optimization through efficiency enhancement; (2) Three leading factors promoting the transition from Phase Ⅰ to Phase Ⅱ include: demographic changes and the emergence of workforce turning point, the reversion of factor elasticity parameters of long-term growth function, and service-oriented economic structure; (3) Developed provinces and municipalities in east China have already entered into the channel of economic deceleration. With increasing urbanization rate, accelerating service-oriented structure and declining demographic dividend after 2016, China's economic slowdown would be inevitable if labor productivity fails to improve.
文摘The problem is what plagued our society since the last decade as far as human resource allocation concerned. HR theory explains the phenomenon of Graduates Employment Dilemma and found a way to solve this problem, from theory and solution perspective. Maslow' s hierarchy of needs has some effect on students' employment. University Students should accelerate the transformation of the concept of employment, to accelerate the pace of structural adjustment, the implementation of the industrialization of education; Guide and encourage students to find a job by using two-factor theory; Make sure college students can stay in a dominant position in the intellectual property of human resource, in order to avoid structural unemployment, so as to make the most use of the students as valuable and effective human resources.
文摘The feasibility of city living with nature as a way to restore the balance between human uses and natural processes is the focus of this paper about the city of Maringa in Southern Brazil. This urban form, a planned new town founded in 1947 upon a previous, comprehensive British land-development scheme, originally offered a friendly interaction between urban settlement and nature. Hence, this paper outlines how open spaces can be enhanced as an ecological structure, bringing parks, squares, gardens and urban farming into a productive system, both for nature's and for people's sakes. Following a morphological study, the proposed ecological structure will maintain ecological processes within the urban grid and help to preserve historical and social values, by linking a wide variety of natural and restored ecosystems and landscape features. The adoption of this kind of ecological planning will certainly result in an increase of the urban landscape quality, changing actual planning paradigm and preventing the city from environmental quality decrease.
文摘Ecosystem valuation can serve as a basis of scientific support for decision-making. So far, the most popular methods for ecosystem valuation are ecosystem service valuation (ESV), which is based on the utility of ecosystem to human beings rather than on the objective value of the ecosystem. After more than 10 years' application, it has been found that all losses of ESV were about 10% of the benefits of human activities. In this paper, the ecosystem intrinsic value (EIV) is defined. EIV is an objective value that emerges from the existence, structures, functions and processes of ecosystem, but independent with man, man's will and preferences. The valuating approach and methods used for EIV were developed by using energy approach and the methods of emergy analysis and eco-exergy analysis. The EIV calculated by emergy from the substance, energy and information of ecosystem and by eco-exergy from the structure and function of ecosystem represents the existent value and the externally working capacity of ecosystem, respectively. The approach and methods of EIV evaluation were applied to Xiamen Bay, China. The results showed that the marine EIV in Xiamen Bay was 209 billion RMB, including 116 billion RMB of emergy and 92.4 billion RMB of eco-exergy in 2010, nearly 30 times of ESV and 8.5 times of the GDP of Xiamen marine industry in 2010. The EIV in unit area of Xiarnen Bay is more than 10 times higher than the average global ESV in estuaries. It implied a potential undervaluation to ecosystem value by ESV calculation, which may mislead decisions-making processes.
文摘Sustainable development indicators, aim to measure sustainable development over longer periods of time. The sustainable development indicators are grouped into 10 subject categories: socioeconomic development, sustainable consumption and production, social inclusion, demographic changes, public health, climate change and energy, sustainable transport, natural resources, global partnership and finally good governance. In this paper, the authors examined a number of researches and compared the methods they used in order to determine the advantages and disadvantages of each method. The methods used a large number of different indicators. The comparison of the indicators could be made through mathematical models and also through theoretical approach.
文摘The term "forgotten city" was mentioned by researchers to denominate some colonial Brazilian settlements and cities which seem to have the same characteristics that demonstrate they were hidden along the years and that have the same atmosphere as they used to in their past life, i.e., they have the same traditional type of urban configuration produced at the origin of the city. This paper brings into discussion this character of this city, using as an example the city of Laranjeiras, one of the oldest cities of the State of Sergipe, which had a great and rich trade of sugar, besides significant cultural and political activities, being known as "Brazilian Athens" in the 19th century. Then, Laranjeiras decayed and stopped growing along the 20th century. However, it has had a good perspective to develop again with insertion of new different activities recently. The initial Portuguese planning to villages in Brazil followed specific rules and had a systematic assistance, what discards the myth that many Brazilian cities were born and grown up as a spontaneous form without planning. Studying some factors deeply, as spatial configuration, settlement localization and urban grid, it can be possible to point some recognizable elements which demonstrate that some cities were built to be forgotten. The methodology used for the analysis of Laranjeiras presents many historic, economic and cultural aspects related to the spatial-syntactic studies (Space Syntax Theory), bringing to light some interesting thoughts about urban form and social life.
基金supported by the National Natural Science Foundation of China(Grant No.51375035)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20121102110021)
文摘Good landing buffering performance can reduce impact and vibration for the bionic locust jumping robot; thus, a landing buffer is important in evaluating the motion performance of the bionic locust robot. In particular, the legs of the robot are the main structures that realize the buffer; thus, its structure affects buffering performance. Three typical leg structure models are established based on the physiological analysis of the locust leg and research status, namely, bionic leg, multi-constraint leg, and arc legs. Kinematic and force analyses are conducted for these types of legs. Particularly, flexible deformation of leg link is considered in the analysis to describe the movement process accurately. In order to compare the buffering performance of these types of legs quantitatively, the performance indices with maximum buffering distance, the energy absorption capability, and the mechanical property are presented. Based on the performance indices, the structure parameters are analyzed and optimized. The buffering performance of the three leg structures is compared with the comprehensive performance of different structures in each best state. This study offers a quantitative analysis and comparison for different legs of bionic locust jumping robot based on landing buffering performance. Furthermore, a theoretical basis for future research and engineering applications is established.
文摘Community spirit is the real essence of community. By involvement in community life, people identify with the communities where they live and work. Thanks to its own distinctive history and cultural environment, Chinese society has a community development and social structure quite distinct from that of the West. Social organizations are not fully developed in China, and the government plays a dominant role in community development. Community building in China should cultivate residents' community consciousness, and be centered on specific social problems such as homelessness, unemployment, family care, poverty, etc.
基金supported in part by the Human Frontier Science Programseveral research grants from Ministry of Education,Culture, Sports, Science, and Technology of Japan+1 种基金the Japan New Energy and Industrial Technology Development Organizationthe Japan Science and Technology Agency
文摘Archaea,the third domain of life,are interesting organisms to study from the aspects of molecular and evolutionary biology.Archaeal cells have a unicellular ultrastructure without a nucleus,resembling bacterial cells,but the proteins involved in genetic information processing pathways,including DNA replication,transcription,and translation,share strong similarities with those of Eukaryota.Therefore,archaea provide useful model systems to understand the more complex mechanisms of genetic information processing in eukaryotic cells.Moreover,the hyperthermophilic archaea provide very stable proteins,which are especially useful for the isolation of replisomal multicomplexes,to analyze their structures and functions.This review focuses on the history,current status,and future directions of archaeal DNA replication studies.
文摘The causes of population differentiation can provide insight into the origins of early barriers to gene flow. Two key drivers of population differentiation are geographic distance and local adaptation to divergent selective environments. When reproductive isolation arises because some populations of a species are under selection to avoid hybridization while others are not, population differentiation and even speciation can result. Spadefoot toad populations Spea multiplicata that are sympatric with a congener have undergone reinforcement. This reinforcement has resulted not only in increased reproductive isolation from the congener, but also in the evolution of reproductive isolation from nearby and distant conspecific allopatric populations. We used multiple approaches to evaluate the contributions of geographic distance and divergent selective environments to population structure across this regional scale in S. multiplicata, based on genotypes from six nuclear microsatellite markers. We compared groups of populations varying in both geographic location and in the presence of a congener. Hierarchical F-statistics and results from cluster analyses and discriminant analyses of principal components all indicate that geographic distance is the stronger contributor to genetic differentiation among S. multiplicata populations at a regional scale. However, we found evidence that adaptation to divergent selective environments also contributes to population structure. Our findings highlight how variation in the balance of evolutionary forces acting across a species' range can lead to variation in the relative contributions of geographic distance and local adaptation to population differentiation across different spatial scales.
文摘Researchers hope that establishing a notion of proximity using topology will help to clarify the biological processes underlying the evolution of living organisms. The simple model presented here, using RNA shapes, can carry over to more general and complex genotype-phenotype systems. Proximity is an important component of continuity, in both real-world and topological terms. Consequently, phenotype spaces provide an appropriate setting for modeling and investigating continuous and discontinuous evolutionary change.