WorldWideScience

Sample records for carrying capacity distribution

  1. Hierarchical population model with a carrying capacity distribution

    CERN Document Server

    Indekeu, J O

    2002-01-01

    A time- and space-discrete model for the growth of a rapidly saturating local biological population $N(x,t)$ is derived from a hierarchical random deposition process previously studied in statistical physics. Two biologically relevant parameters, the probabilities of birth, $B$, and of death, $D$, determine the carrying capacity $K$. Due to the randomness the population depends strongly on position, $x$, and there is a distribution of carrying capacities, $\\Pi (K)$. This distribution has self-similar character owing to the imposed hierarchy. The most probable carrying capacity and its probability are studied as a function of $B$ and $D$. The effective growth rate decreases with time, roughly as in a Verhulst process. The model is possibly applicable, for example, to bacteria forming a "towering pillar" biofilm. The bacteria divide on randomly distributed nutrient-rich regions and are exposed to random local bactericidal agent (antibiotic spray). A gradual overall temperature change away from optimal growth co...

  2. Carrying Capacity

    DEFF Research Database (Denmark)

    Schroll, Henning; Andersen, Jan; Kjærgård, Bente

    2012-01-01

    A spatial planning act was introduced inIndonesia 1992 and renewed in 2008. It emphasised the planning role of decentralised authorities. The spatial planning act covers both spatial and environmental issues. It defines the concept of carrying capacity and includes definitions of supportive...... carrying capacity (SCC) and assimilative carrying capacity (ACC). The act mandates that the latter two aspects must be taken into consideration in the local spatial plans. The present study aimed at developing a background for a national guideline for carrying capacity in Indonesian provinces and districts...... standard or governmental political objective exists. In most cases it was possible to select a set of indicators, including thresholds that are workable in a carrying capacity planning at the local administrative levels. Not all relevant sectors at the decentralized level were included. Indicators of SCC...

  3. Carrying Capacity

    DEFF Research Database (Denmark)

    Schroll, Henning; Andersen, Jan; Kjærgård, Bente

    2012-01-01

    A spatial planning act was introduced inIndonesia 1992 and renewed in 2008. It emphasised the planning role of decentralised authorities. The spatial planning act covers both spatial and environmental issues. It defines the concept of carrying capacity and includes definitions of supportive...... and ACC may increase the political focus on resources and environmental issues and may help to move local authorities towards a more holistic spatial planning approach. A carrying capacity approach could be an inspiration for local spatial planning in developing countries. A spatial planning act...... was introduced inIndonesia 1992 and renewed in 2008. It emphasised the planning role of decentralised authorities. The spatial planning act covers both spatial and environmental issues. It defines the concept of carrying capacity and includes definitions of supportive carrying capacity (SCC) and assimilative...

  4. Carrying Capacity:An Overview

    Institute of Scientific and Technical Information of China (English)

    Chen Shaofeng

    2004-01-01

    The concept of carrying capacity is derived from ecology, with widespread contentions of its theoretical connotations and applications in the international academic community, especially the impact of human activities on the environment.Disputes on carrying capacity have been occurring not only among biologists and ecologists, but also among mainstream economists. Based on their efforts,the author makes an attempt to describe its origin,connotations, problems, measurement, and at the same time note the latest international progress in this field.

  5. 25 CFR 167.6 - Carrying capacities.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Carrying capacities. 167.6 Section 167.6 Indians BUREAU... Carrying capacities. (a) The Commissioner of Indian Affairs on June 26, 1943, promulgated the authorized carrying capacity for each land management district of the Navajo Reservation. (b) Recommended...

  6. 7 CFR 1437.402 - Carrying capacity.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Carrying capacity. 1437.402 Section 1437.402... Determining Coverage of Forage Intended for Animal Consumption § 1437.402 Carrying capacity. (a) CCC will establish a carrying capacity for all grazed forage present in the county for purposes of administering...

  7. ENVIRONMENTAL CARRYING CAPACITY BASED ON SPATIAL PLANNING

    OpenAIRE

    Luthfi Muta'ali

    2013-01-01

    The aims of this research were to examine environmental carrying capacity analyzed based on aspects of spatial planning and eco-region. The result showed that Kulonprogo Regency has low value of environmental carrying capacity and can only support as much as 79.81% of its total population. Analysis of variance showed significant difference of environmental carrying capacity of protected and cultivated area. The main factor among 12 variables determining the degree of environmen...

  8. Bivalve carrying capacity in coastal ecosystems

    NARCIS (Netherlands)

    Dame, R.F.; Prins, T.C.

    1998-01-01

    carrying capacity of suspension feeding bivalves in 11 coastal and estuarine ecosystems is examined. Bivalve carrying capacity is defined in terms of water mass residence time, primary production time and bivalve clearance time. Turnover times for the 11 ecosystems are compared both two and three di

  9. The Concept of Carrying Capacity in Tourism

    Directory of Open Access Journals (Sweden)

    Josef Zelenka

    2014-05-01

    Full Text Available Carrying capacity is often pragmatically, theoretically as well as purely intuitively considered as a concept in the context of tourism sustainability. The carrying capacity application has the greatest potential in protected areas, in frequently visited cultural and natural attractions, and in relation to sustaining of the lifestyle of the local community and tourism destination potential in general. Despite its importance, partial applications, determination of basic theoretical principles, and specifying connection to the other theoretical concepts in tourism (particularly destination life cycle, LAC concept, visitors management, there still is a rightful opinion of some authors suggesting that there is no consistent theory of tourism carrying capacity. This theory would be the base for sophisticated practical carrying capacity applications. This paper is therefore focused on introduction of the theoretical concept of carrying capacity, which can be discussed and possibly further elaborated.

  10. Measuring Social Carrying Capacity: An Exploratory Study

    OpenAIRE

    López-Bonilla, Jesús Manuel; López-Bonilla, Luis Miguel

    2007-01-01

    The tourist carrying capacity commands a growing interest given that it is closely linked with sustainable tourist development. The justification of the utility of this concept is given by means of a simple and efficient methodological proposal, by analysing the social carrying capacity. To this end, an empirical application is carried out in the Western Andalusia. In some of the cases analysed, the satisfaction of the tourist is found to decline when the levels of the tourist use are higher ...

  11. Optimal growth trajectories with finite carrying capacity.

    Science.gov (United States)

    Caravelli, F; Sindoni, L; Caccioli, F; Ududec, C

    2016-08-01

    We consider the problem of finding optimal strategies that maximize the average growth rate of multiplicative stochastic processes. For a geometric Brownian motion, the problem is solved through the so-called Kelly criterion, according to which the optimal growth rate is achieved by investing a constant given fraction of resources at any step of the dynamics. We generalize these finding to the case of dynamical equations with finite carrying capacity, which can find applications in biology, mathematical ecology, and finance. We formulate the problem in terms of a stochastic process with multiplicative noise and a nonlinear drift term that is determined by the specific functional form of carrying capacity. We solve the stochastic equation for two classes of carrying capacity functions (power laws and logarithmic), and in both cases we compute the optimal trajectories of the control parameter. We further test the validity of our analytical results using numerical simulations.

  12. Optimal growth trajectories with finite carrying capacity

    Science.gov (United States)

    Caravelli, F.; Sindoni, L.; Caccioli, F.; Ududec, C.

    2016-08-01

    We consider the problem of finding optimal strategies that maximize the average growth rate of multiplicative stochastic processes. For a geometric Brownian motion, the problem is solved through the so-called Kelly criterion, according to which the optimal growth rate is achieved by investing a constant given fraction of resources at any step of the dynamics. We generalize these finding to the case of dynamical equations with finite carrying capacity, which can find applications in biology, mathematical ecology, and finance. We formulate the problem in terms of a stochastic process with multiplicative noise and a nonlinear drift term that is determined by the specific functional form of carrying capacity. We solve the stochastic equation for two classes of carrying capacity functions (power laws and logarithmic), and in both cases we compute the optimal trajectories of the control parameter. We further test the validity of our analytical results using numerical simulations.

  13. Error propagation in energetic carrying capacity models

    Science.gov (United States)

    Pearse, Aaron T.; Stafford, Joshua D.

    2014-01-01

    Conservation objectives derived from carrying capacity models have been used to inform management of landscapes for wildlife populations. Energetic carrying capacity models are particularly useful in conservation planning for wildlife; these models use estimates of food abundance and energetic requirements of wildlife to target conservation actions. We provide a general method for incorporating a foraging threshold (i.e., density of food at which foraging becomes unprofitable) when estimating food availability with energetic carrying capacity models. We use a hypothetical example to describe how past methods for adjustment of foraging thresholds biased results of energetic carrying capacity models in certain instances. Adjusting foraging thresholds at the patch level of the species of interest provides results consistent with ecological foraging theory. Presentation of two case studies suggest variation in bias which, in certain instances, created large errors in conservation objectives and may have led to inefficient allocation of limited resources. Our results also illustrate how small errors or biases in application of input parameters, when extrapolated to large spatial extents, propagate errors in conservation planning and can have negative implications for target populations.

  14. Increased carrying capacity with perennial forage kochia

    Science.gov (United States)

    Carrying capacity can be increased on grass-dominated rangeland pastures by including perennial forage kochia (Kochia prostrata) as one of the plant components. The objectives of the study reported here were to compare the differences of traditional winter pastures versus pastures with forage kochi...

  15. Carrying Capacity of Marine Region in Liaoning Province

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Carrying capacity is one of important studies on coordinating development of population, resources, and environment. At present, the researches on it mainly concentrate on the carrying capacity for population and economy,such as the water resources carrying capacity, the land resources carrying capacity, the environment carrying capacity,etc. Based on the related theories and methods, this paper creatively proposed the concept and meaning of carrying capacity of marine region, and formed the appraisal system. According to the developing situation of marine economy of Liaoning Province in recent years, and by employing the method of the state space, this paper also measured the cartying capacity and carrying state of marine region and discussed the sustainable problems of marine economy of Liaoning. The research results show that the carrying state of marine region of Liaoning is in the state of overloading at present, but taking a favorable turn.

  16. Information carrying capacity of a cosmological constant

    Science.gov (United States)

    Simidzija, Petar; Martín-Martínez, Eduardo

    2017-01-01

    We analyze the exchange of information in different cosmological backgrounds when sender and receiver are timelike separated and communicate through massless fields (without the exchange of light signals). Remarkably, we show that the dominance of a cosmological constant makes the amount of recoverable information imprinted in the field by the sender extremely resilient: it does not decay in time or with the spatial separation of the sender and receiver, and it actually increases with the rate of expansion of the Universe. This is in stark contrast with the information carried by conventional light signals and with previous results on timelike communication through massless fields in matter-dominated cosmologies.

  17. Regional carrying capacity: case studies of Bohai Rim area

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Carrying capacity research has been carried out for a long time. However, synthesized carrying capacity researches based on systematic views began only in the 1970s. There is even less work done in China. This paper tries to address both synthesized carrying capacity research and its utilization in China. State spaces method from the systematic science was borrowed to construct the conceptual model of regional carrying capacity. Based on the conceptual model and the surveys in the Bohai Rim area, we construct a representative indicators system for quantifying regional carrying capacity in the Bohai Rim. While employing system dynamic models we simulated the evolving trend of both the regional carrying states and regional carrying capacity from 1999 to 2015. The results proved the statement that Bohai Rim is overall over-capacity for a long time and will be over-capacity in the foreseeable future. Among all the restriction factors, water shortage and environmental pollution stand out to be the two primary obstacles for Bohai Rim's sustainable development.Regional differentiation analysis further indicates that coastal areas of the Bohai Rim burden more than its overall level. However, Shandong province shows some good signs in addressing the regional carrying capacity issues. The research is successful in addressing the quantification of regional carrying capacity issues, but nonetheless it needs further refinery and more information.

  18. Research on Psychological Carrying Capacity of Tourism Destination

    Institute of Scientific and Technical Information of China (English)

    Fan Zhiyong; Zhong Sheng

    2009-01-01

    As a part of the carrying capacity system of tourism destination,tourism psychological carrying capacity and its makeup are very important indexes which reflect the harmonious development of tourism destination develops harmoniously,but the academy has not paid enough attention to them.Based on the concept and connotation of psychological carrying capacity,this paper explains the influencing factors which affect the psychological capacity of the tourist and the resident after the acknowledged concept,and then designs a harmonious development model of tourism destination.Finally,it offers some countermeasures against the overloading psychological capacity.

  19. Global change and carrying capacity: Implications for life on Earth

    Science.gov (United States)

    Ehrlich, Paul R.; Daily, Gretchen C.; Ehrlich, Anne H.; Matson, Pamela; Vitousek, Peter

    1989-01-01

    Determining the long-term number of people that the planet can support without irreversibly reducing its ability to support people in the future, i.e., the carrying capacity of the Earth, is an exceedingly complex problem. About all that is known for certain is that, with present and foreseeable technologies, the human population has already exceeded the capacity. The reduction in carrying capacity that can be expected to result from direct human impacts on resources and the environment and from our indirect impacts of the climate system is discussed. Global warming and modeling global change and food security are also discussed with respect to carrying capacity.

  20. Global change and carrying capacity: Implications for life on Earth

    Science.gov (United States)

    Ehrlich, Paul R.; Daily, Gretchen C.; Ehrlich, Anne H.; Matson, Pamela; Vitousek, Peter

    1989-01-01

    Determining the long-term number of people that the planet can support without irreversibly reducing its ability to support people in the future, i.e., the carrying capacity of the Earth, is an exceedingly complex problem. About all that is known for certain is that, with present and foreseeable technologies, the human population has already exceeded the capacity. The reduction in carrying capacity that can be expected to result from direct human impacts on resources and the environment and from our indirect impacts of the climate system is discussed. Global warming and modeling global change and food security are also discussed with respect to carrying capacity.

  1. Estimating the recreational carrying capacity of a lowland river section.

    Science.gov (United States)

    Lorenz, Stefan; Pusch, Martin T

    2012-01-01

    Recreational boating represents a major human use of inland waters in many regions. However, boating tourism may affect the ecological integrity of surface waters in multiple ways. In particular, surface waves produced by boating may disturb freshwater invertebrates, such as interrupting the filtration activity of benthic mussels. As mussels may significantly contribute to self-purification, disturbance may have crucial impacts on water quality, and thus on water tourism. In this paper we calculate the carrying capacity of a river section for sustainable boating tourism based on the preservation of water quality. This approach is complemented by spatial and social approaches for carrying capacity estimates. The ecological carrying capacity significantly decreases with lower water levels during summer. Hence, the analysis of variables that influence the river's carrying capacity allows the formation of recommendations for management measures that integrate social, touristic and ecological aspects.

  2. Study on Tourist Carrying Capacity Based on Matter Element Analysis

    Institute of Scientific and Technical Information of China (English)

    LiuYunguo; FanTing; LiXin; ZhouMing; WangXianhai

    2005-01-01

    This paper proposes that it is necessary to implement the concept of tourist carrying capacity to facilitate the tourism planning, and presents a method to evaluate the carrying capacity. The method called matter element analysis can solve the uncertain and incompatible problem of the evaluated factors in assessing carrying capacity.The current state of a destination's carrying capacity can be determined by establishing the standard indexes and the matter element model. Through the evaluating of the travel industry zones of the Autonomous Prefecture of Western Hunan, the method is proved to be simple and feasible, and it is improved to be significant for the tourism planning and determination as well as the sustainable development of the regional tourism.

  3. Determination of the sediment carrying capacity based on perturbed theory.

    Science.gov (United States)

    Ni, Zhi-hui; Zeng, Qiang; Li-chun, Wu

    2014-01-01

    According to the previous studies of sediment carrying capacity, a new method of sediment carrying capacity on perturbed theory was proposed. By taking into account the average water depth, average flow velocity, settling velocity, and other influencing factors and introducing the median grain size as one main influencing factor in deriving the new formula, we established a new sediment carrying capacity formula. The coefficients were determined by the principle of dimensional analysis, multiple linear regression method, and the least square method. After that, the new formula was verified through measuring data of natural rivers and flume tests and comparing the verified results calculated by Cao Formula, Zhang Formula, Li Formula, Engelung-Hansen Formula, Ackers-White Formula, and Yang Formula. According to the compared results, it can be seen that the new method is of high accuracy. It could be a useful reference for the determination of sediment carrying capacity.

  4. The logistic model-generated carrying capacities for wild herbivores ...

    African Journals Online (AJOL)

    Jesse

    Modelled as discrete-time logistic equations with fixed carrying capacities, it captures the wildlife herbivore population dynamics. Time series data, covering a period ..... Building Models for Conservation and. Wildlife Management. (New York ...

  5. Langkawi Island, Social Aspect and the Carrying Capacity

    OpenAIRE

    Mohamad Diana; Jaafar Mastura; Marzuki Azizan

    2014-01-01

    The aptitude to convince a range of preferences has facilitated the island tourism attractions to achieve international recognition and at present KILIM Geopark is enjoyed by a prominent percentage of individuals wide-reaching. Conventional knowledge has that the island attractions are operating on the limited immobile resources, of which, have raised the scholars’ concerns over the carrying capacity issue. When analyzing carrying capacity, scholars have traditionally focused on the environme...

  6. Carrying capacity: the tradition and policy implications of limits

    Directory of Open Access Journals (Sweden)

    Virginia Deane Abernethy

    2001-01-01

    Full Text Available ABSTRACT: Within just the last few centuries, science and technology have enlarged human capabilities and population size until humans now take, for their own use, nearly half of the Earth's net terrestrial primary production. An ethical perspective suggests that potentials to alter, or further increase, humanity's use of global resources should be scrutinized through the lenses of self-interested foresightedness and respect for non-human life. Without overtly invoking ethics, studies of the carrying capacity achieve just this objective. Carrying capacity is an ecological concept that expresses the relationship between a population and the natural environment on which it depends for ongoing sustenance. Carrying capacity assumes limits on the number of individuals that can be supported at a given level of consumption without degrading the environment and, therefore, reducing future carrying capacity. That is, carrying capacity addresses long-term sustainability. Worldviews differ in the importance accorded to the carrying capacity concept. This paper addresses three worldviews - ecological, romantic, and entrepreneurial - and explores the ethics and the policy implications of their contrasting perspectives.

  7. Integrated Coastal Zone Planning Based on Environment Carrying Capacity Analysis

    Science.gov (United States)

    Miharja, M.; Arsallia, S.

    2017-07-01

    Coastal zone is a crucial area in terms of planning development. It holds high economic value, which affect to increasing number of inhabitants living in the area. As a result, this condition influences environmental degradation. Thus, in every attempt towards coastal zone development, it is crucial to always refer to environment carrying capacity. Carrying capacity is the limit of a certain coastal zone capability to support all human created activities, in which all ecological performances are maintained at sustainable level. The failure to establish strong and clear method and regulation on carrying capacity analysis will lead to a very risky coastal zone development, which in turn would threat the area’s sustainability. This paper discusses method for analysing carrying capacity of coastal zone as important input for the area development plan. Two key parameters, i.e. land and clean water carrying capacities are discussed to form carrying capacity analytical method. Furthermore, an empirical data of Ambon Bay, Moluccas Province, is used to illustrate the operationalization of the method.

  8. Boundary slippage for generating hydrodynamic load-carrying capacity

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yong-bin

    2008-01-01

    Boundary slippage is used to generate the load-carrying capacity of the hydrodynamic contact between two parallel plane surfaces.In the fluid inlet zone,the fluidcontact interfacial shear strength on a stationary surface is set at low to generate boundary slippage there,while in the fluid outlet zone the fluid-contact interfacial shear strength on the stationary surface is set at high enough to prevent the occurrence of boundary slippage.The fluid-contact interfacial shear strength on the entire moving surface is set at high enough to prevent boundary slippage on the moving surface.These hydrodynamic contact configurations are analyzed to generate the pronounced load-carrying capacity.The optimum ratio of the outlet zone width to the inlet zone width for the maximum load-carrying capacity of the whole contact is found to be 0.5.

  9. Effects of box handle position and carrying range on bi-manual carrying capacity for females.

    Science.gov (United States)

    Wu, Swei-Pi; Loiu, Yi; Chien, Te Hong

    2015-01-01

    This study utilizes a psychophysical approach to examine the effects on carrying capacity for bi-manual carrying tasks involving different handle positions and carrying ranges. A total of 16 female subjects participated in the experiment in groups of two people, and each group of subjects performed the tasks in a random order with 12 different combinations of carrying task. The independent variables are handle position (upper, middle, lower) and carrying range (F-F: floor height carried to floor height, F-W: floor height carried to waist height, W-W: waist height carried to waist height, W-F: waist height carried to floor height), the dependent variable is the maximum acceptable carried weight (MAWC), heart rate (HR), and the rating of perceived exertion (RPE). The results show that the handle position has a significant effect on MAWC and overall RPE but no significant effect on HR. Carrying range has a significant effect on the MAWC and HR, but no significant effect on overall HR. The handle position and carrying range have a significant interaction on the MAWC and HR. The RPE for different body parts shows significant differences, and the hands feel the most tired. Overall, this study confirms that the lower handle position with the W-W carrying range is the best combination for a two-person carrying task.

  10. Evaluation of carrying capacity and territorial environmental sustainability

    Directory of Open Access Journals (Sweden)

    Giuseppe Ruggiero

    2012-09-01

    Full Text Available Land use has a great impact on environmental quality, use of resources, state of ecosystems and socio-economic development. Land use can be considered sustainable if the environmental pressures of human activities do not exceed the ecological carrying capacity. A scientific knowledge of the capability of ecosystems to provide resources and absorb waste is a useful and innovative means of supporting territorial planning. This study examines the area of the Province of Bari to estimate the ecosystems’ carrying capacity, and compare it with the current environmental pressures exerted by human activities. The adapted methodology identified the environmentally sustainable level for one province.

  11. Model Modification and Application on Carrying Capacity of Relative Resources

    Institute of Scientific and Technical Information of China (English)

    Li Zehong; Dong Suocheng; Gao Dan

    2009-01-01

    Based on the retrospection of researches on carry-ing capacity, this article reviewed systematically the research progresses on carrying capacity of relative resources (CCRR).Then the viewpoint was put forward that CCRR is not an ap-propriate method of appraising the regional sustainability, but a sound way to obtain cognition for coordinating spatial loca-tion and flow of population and economy.However, as the most popular computing method of CCRR, the Weighting Linear Sum Model is defective in the random of weight choice and the neglect of matching among different resources.Therefore, this article established the Geometric Model on CCRR based on modifying Weighting Linear Sum Model, which can be used to appraise regions where resources are close matching.Em-ploying the Geometric Model, the article empirically analyzed the population and economic CCRR in Hubei Province from 1978 to 2006.The result indicates that the population in Hubei Province is overloading while the economic carrying capacity is abundant compared to the whole country, and the economic insufficiency restricts the population carrying capacity.In the future, Hubei Province will become one of the core developing zones which are characterized by economic conglomeration.

  12. Cultural Carrying Capacity: A Biological Approach to Human Problems.

    Science.gov (United States)

    Hardin, Garrett

    1992-01-01

    In discussing the human and cultural implications of scientific discoveries and knowledge, the biological concept of carrying capacity is explored. Maintaining that human beings are truly animals answering to principles that govern all animals, the author addresses the need for human populations to work within the context of culture and carrying…

  13. Modeling the Flexural Carrying Capacity of Corroded RC Beam

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-hui; LIU Xi-la

    2008-01-01

    Considering the change of bond strength between corroded steel and concrete, flexural carrying ca-pacity of corroded reinforced concrete (RC) beam was calculated. On the basis of the condition of equilibriumof forces and compatibility of deformations for the whole beam, a model for the prediction of flexural carryingcapacity of the corroded RC beam was proposed. Comparison of the model's predictions with the experimentalresults published in the literature shows the practicality of the proposed method.

  14. Estimating landscape carrying capacity through maximum clique analysis.

    Science.gov (United States)

    Donovan, Therese M; Warrington, Gregory S; Schwenk, W Scott; Dinitz, Jeffrey H

    2012-12-01

    Habitat suitability (HS) maps are widely used tools in wildlife science and establish a link between wildlife populations and landscape pattern. Although HS maps spatially depict the distribution of optimal resources for a species, they do not reveal the population size a landscape is capable of supporting--information that is often crucial for decision makers and managers. We used a new approach, "maximum clique analysis," to demonstrate how HS maps for territorial species can be used to estimate the carrying capacity, N(k), of a given landscape. We estimated the N(k) of Ovenbirds (Seiurus aurocapillus) and bobcats (Lynx rufus) in an 1153-km2 study area in Vermont, USA. These two species were selected to highlight different approaches in building an HS map as well as computational challenges that can arise in a maximum clique analysis. We derived 30-m2 HS maps for each species via occupancy modeling (Ovenbird) and by resource utilization modeling (bobcats). For each species, we then identified all pixel locations on the map (points) that had sufficient resources in the surrounding area to maintain a home range (termed a "pseudo-home range"). These locations were converted to a mathematical graph, where any two points were linked if two pseudo-home ranges could exist on the landscape without violating territory boundaries. We used the program Cliquer to find the maximum clique of each graph. The resulting estimates of N(k) = 236 Ovenbirds and N(k) = 42 female bobcats were sensitive to different assumptions and model inputs. Estimates of N(k) via alternative, ad hoc methods were 1.4 to > 30 times greater than the maximum clique estimate, suggesting that the alternative results may be upwardly biased. The maximum clique analysis was computationally intensive but could handle problems with < 1500 total pseudo-home ranges (points). Given present computational constraints, it is best suited for species that occur in clustered distributions (where the problem can be

  15. Langkawi Island, Social Aspect and the Carrying Capacity

    Directory of Open Access Journals (Sweden)

    Mohamad Diana

    2014-01-01

    Full Text Available The aptitude to convince a range of preferences has facilitated the island tourism attractions to achieve international recognition and at present KILIM Geopark is enjoyed by a prominent percentage of individuals wide-reaching. Conventional knowledge has that the island attractions are operating on the limited immobile resources, of which, have raised the scholars’ concerns over the carrying capacity issue. When analyzing carrying capacity, scholars have traditionally focused on the environmental part, hence, this working paper is motivated to convey onto the table issues relating to the social characteristics. This particular paper employed the self-administered questionnaire survey instrument which was structured to answer the two-fold objective specifically the tourists’ satisfaction level with their tourism experience and knowledge gap in relation to improving the island tourism. Targeting the tourists with minimum age of 18, this working paper collects information on the tourists’ perception towards hospitality, facilities and safety issues. In addition, this working paper comes to scrutinize different results of demographic factors as compared to what have been documented by earlier studies. Besides, it is learned that ‘safety issue’ variable plays an important role when it comes to the following factors: tourist arrival, access to facilities and tourism experience.

  16. Modeling symbiosis by interactions through species carrying capacities

    Science.gov (United States)

    Yukalov, V. I.; Yukalova, E. P.; Sornette, D.

    2012-08-01

    We introduce a mathematical model of symbiosis between different species by taking into account the influence of each species on the carrying capacities of the others. The modeled entities can pertain to biological and ecological societies or to social, economic and financial societies. Our model includes three basic types: symbiosis with direct mutual interactions, symbiosis with asymmetric interactions, and symbiosis without direct interactions. In all cases, we provide a complete classification of all admissible dynamical regimes. The proposed model of symbiosis turned out to be very rich, as it exhibits four qualitatively different regimes: convergence to stationary states, unbounded exponential growth, finite-time singularity, and finite-time death or extinction of species.

  17. The Population Carrying Capacity of Water Resources in Yulin City

    Institute of Scientific and Technical Information of China (English)

    Lijuan; DANG; Yong; XU; Zhiqiang; WANG

    2014-01-01

    Assessing the water resource carrying capacity is beneficial for measuring the scale of industry and population agglomeration,and also avoiding the contradiction between increasing people and decreasing available water resource,due to the expansion of industry and city size.Based on the prediction model of optimum population development size,by using hydrological data,also with the demographic data from 1956 to 2010,this article analyzes and predicts the urban moderate scale under the limit of the water resource in the future of Yulin City by GIS. The main conclusions are as follows. There is growing tendency of water resources overloading. According to the result of model simulation,by2015,the overload rate of population size will be 1. 04. By 2020,the overload rate of population size will grow up to 1. 08. The oversized population mainly comes from cities and towns. The overload rate for cities and towns in 2015 and 2020 is 1. 89 and 1. 73,respectively. With the expansion of cities and industries,suburban areas could have a great potential for carrying population,because lots of suburban people may move to cities and towns according to prediction. In view of the above-mentioned facts,the population size should be controlled in a reasonable range.

  18. Wildlife carrying capacities in relation to human settlement

    Directory of Open Access Journals (Sweden)

    S.K. Eltringham

    1990-09-01

    Full Text Available Human encroachment into wildlife areas, which has increased almost exponentially over the past few decades, has usually resulted in the elimination of the larger species, particularly the large mammals. This is not an inevitable consequence and this paper considers the extent to which man and wildlife can coexist. There is a linear inverse relationship between human and elephant densities and the reasons for this are discussed with particular reference to Uganda. Such a relationship does not necessarily hold for all species and the outcome of increasing human pressure on wildlife habitats varies with a variety of factors including the species concerned, the rainfall, vegetation, soil and, above all, the attitudes of the people towards wildlife. Wild animals are more likely to be tolerated if they do no harm to human activities or if the harm they do is outweighed by the benefits to be obtained from their exploitation. In many parts of Africa utilisation is likely to be the best hope for the conservation of wildlife. Some examples are given of situations in which worthwhile carrying capacities of wildlife can be maintained in the presence of human activities.

  19. The Analysis and Calculation Method of Urban Rail Transit Carrying Capacity Based on Express-Slow Mode

    OpenAIRE

    Xiaobing Ding; Shengrun Zhang; Zhigang Liu; Hua Hu; Xingfang Xu; Weixiang Xu

    2016-01-01

    Urban railway transport that connects suburbs and city areas is characterized by uneven temporal and spatial distribution in terms of passenger flow and underutilized carrying capacity. This paper aims to develop methodologies to measure the carrying capacity of the urban railway by introducing a concept of the express-slow mode. We first explore factors influencing the carrying capacity under the express-slow mode and the interactive relationships among these factors. Then we establish seven...

  20. Spatial patterns of ecological carrying capacity supply-demand balance in China at county level

    Institute of Scientific and Technical Information of China (English)

    LIU Dong; FENG Zhiming; YANG Yanzhao; YOU Zhen

    2011-01-01

    A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependencies between human and nature.China's ecological balance between supply and demand has become a global concern and is widely debated.In this study the 'Ecological Footprint' method was used to analyze the supply-demand balance of China's ecological carrying capacity.Firstly,the ecological supply and demand balance was calculated and evaluated,and secondly,the ecological carrying capacity index (ECCI) was derived for each county of China in 2007,and finally this paper systematically evaluated the ecological carrying capacity supply-demand balance of China.The results showed that ecological deficit appeared to be the main characteristic of ecological carrying capacity supply-demand balance in 2007 of China at county scale.In general,more than four-fifths of the Chinese population was concentrated in less than one-third of the land area and more than two-thirds of the land.area was inhabited by less than one-fifth of the population.The spatial distribution of the ecological carrying capacity demand-supply was unbalanced ranging from significant overloading to affluence from southeastern to northwestern part of China.It appeared to be more dominant in regions located at coastal areas which are attracted by migrants and had a generally higher population density.Along with the rapid development and urbanization trends in China,ecological deficits in these regions will become more severe.

  1. Dynamic Carrying Capacity Analysis of Double-Row Four-Point Contact Ball Slewing Bearing

    OpenAIRE

    Yunfeng Li; Di Jiang

    2015-01-01

    Carrying capacity is the most important performance index for slewing bearings. Maximizing the carrying capacity of slewing bearing is one pursuing goal for the bearing designer; this is usually realized by optimizing the design parameters. A method of analyzing the carrying capacity of double-row four-point contact ball slewing bearing by using dynamic carrying capacity surfaces was proposed in this paper. Based on the dynamic load carrying capacity surface of the slewing bearing, the effect...

  2. Effects of carrying methods and box handles on two-person team carrying capacity for females.

    Science.gov (United States)

    Wu, Swei-Pi; Chang, Shu-Yu

    2010-07-01

    This study used a psychophysical approach to examine the effects of carrying methods and the presence or absence of box handles on the maximum acceptable weight carried and resulting responses (heart rate and rating of perceived exertion) in a two-person carrying task. After training, 16 female subjects performed a two-person carrying task at knuckle height for an 8-h work period. Each subject performed 4 different carrying combinations two times. The independent variables were carrying methods (parallel and tandem walking) and box handles (with and without handles). For comparison with two-person carrying, the subjects also performed one-person carrying. The results showed that the maximum acceptable weight carried (MAWC), heart rate (HR), and rating of perceived exertion (RPE) were significantly affected by the presence of box handles. However, the subjects' MAWC, HR, and RPE values were not significantly influenced by the carrying methods. The test-retest reliability of the psychophysical approach was 0.945. The carrying efficiency of two-person carrying was 96.2% of the one-person carrying method. In general, the use of box with handles allows the subjects to carry a higher MAWC (with lower HR and RPE) compared to carrying boxes without handles.

  3. [Ecotourism carrying capacity of Hangzhou Xixi National Wetland Park in China].

    Science.gov (United States)

    Li, Rui; Rong, Liang

    2007-10-01

    In this paper, an integrated estimation on the ecotourism carrying capacity of Hangzhou Xixi National Wetland Park in China was made from the aspects of ecological carrying capacity, spatial carrying capacity, facility carrying capacity, management carrying capacity, and psychological carrying capacity. The results indicated that the tourism carrying capacity of the Park was 4 145 - 6 450 persons per day. The rational distance between man and bird was first adopted to determine the ecotourism carrying capacity of wetland, which provided an effective solution both to fully ensure bird safety and to appropriately develop wetland tourism. The estimation of psychological carrying capacity based on tourist satisfaction degree reflected more objectively the extent the tourist demands satisfied at the planning, construction and management of tour places. Such an integrated estimation method based on the distance between man and bird and the tourist satisfaction degree could be of practical and instructive significances in the planning and management of wetland parks.

  4. 25 CFR 161.204 - How are carrying capacities and stocking rates established?

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false How are carrying capacities and stocking rates... WATER NAVAJO PARTITIONED LANDS GRAZING PERMITS General Provisions § 161.204 How are carrying capacities..., review and adjust the carrying capacity of each range unit by determining the number of livestock,...

  5. The information carrying capacity of a cosmological constant

    CERN Document Server

    Simidzija, Petar

    2016-01-01

    We analyze the exchange of information in different cosmological backgrounds when sender and receiver are timelike separated and communicate through massless fields (without the exchange of light-signals). Remarkably, we show that the dominance of a cosmological constant makes the amount of recoverable information imprinted in the field by the sender extremely resilient: it does not decay in time or with the spatial separation of sender and receiver, and it actually increases with the rate of expansion of the Universe. This is in stark contrast with the information carried by conventional light-signals and with previous results on timelike communication through massless fields in matter dominated cosmologies.

  6. An innovative method for water resources carrying capacity research--Metabolic theory of regional water resources.

    Science.gov (United States)

    Ren, Chongfeng; Guo, Ping; Li, Mo; Li, Ruihuan

    2016-02-01

    The shortage and uneven spatial and temporal distribution of water resources has seriously restricted the sustainable development of regional society and economy. In this study, a metabolic theory for regional water resources was proposed by introducing the biological metabolism concept into the carrying capacity of regional water resources. In the organic metabolic process of water resources, the socio-economic system consumes water resources, while products, services and pollutants, etc. are output. Furthermore, an evaluation index system which takes into the characteristics of the regional water resources, the socio-economic system and the sustainable development principle was established based on the proposed theory. The theory was then applied to a case study to prove its availability. Further, suggestions aiming at improving the regional water carrying capacity were given on the basis of a comprehensive analysis of the current water resources situation.

  7. Land Potential Productivity and Population Carrying Capacity of Yan’an City

    Institute of Scientific and Technical Information of China (English)

    Xiaoling; LIU; Wei; ZHANG

    2013-01-01

    The productivity attenuation method is adopted to calculate land potential productivity of counties of Yan’an City and calculate population carrying capacity at current productivity level. Result shows that high photosynthetic potential productivity area and high light and temperature potential productivity area are mainly situated in the north,while high climatic potential area and high land potential productivity area are mainly concentrated in the south. From solar radiation,moisture and landform,the attenuation amplitude of land potential productivity in northern counties ( districts) is greater than that in southern counties ( districts) . In the whole city,the population carrying capacity of 9 counties reaches well-off living level,and 1 district still does not reach the level of adequate food and clothing. These results can provide reference for land resource use,agricultural production distribution and population growth control.

  8. Dynamic Carrying Capacity Analysis of Double-Row Four-Point Contact Ball Slewing Bearing

    Directory of Open Access Journals (Sweden)

    Yunfeng Li

    2015-01-01

    Full Text Available Carrying capacity is the most important performance index for slewing bearings. Maximizing the carrying capacity of slewing bearing is one pursuing goal for the bearing designer; this is usually realized by optimizing the design parameters. A method of analyzing the carrying capacity of double-row four-point contact ball slewing bearing by using dynamic carrying capacity surfaces was proposed in this paper. Based on the dynamic load carrying capacity surface of the slewing bearing, the effect of changes of the bearing design parameters, such as axial clearance, raceway groove radius coefficient, and contact angle, on the dynamic carrying capacity of the slewing bearing was researched; the trend and the degree of the effect of the micro changes of the bearing design parameters on the dynamic load carrying capacity of the bearing were discussed, and the results provide the basis for optimizing the design parameter of this type of slewing bearing.

  9. Delivering Transgenic DNA Exceeding the Carrying Capacity of AAV Vectors.

    Science.gov (United States)

    Hirsch, Matthew L; Wolf, Sonya J; Samulski, R J

    2016-01-01

    Gene delivery using recombinant adeno-associated virus (rAAV) has emerged to the forefront demonstrating safe and effective phenotypic correction of diverse diseases including hemophilia B and Leber's congenital amaurosis. In addition to rAAV's high efficiency of transduction and the capacity for long-term transgene expression, the safety profile of rAAV remains unsoiled in humans with no deleterious vector-related consequences observed thus far. Despite these favorable attributes, rAAV vectors have a major disadvantage preventing widespread therapeutic applications; as the AAV capsid is the smallest described to date, it cannot package "large" genomes. Currently, the packaging capacity of rAAV has yet to be definitively defined but is approximately 5 kb, which has served as a limitation for large gene transfer. There are two main approaches that have been developed to overcome this limitation, split AAV vectors, and fragment AAV (fAAV) genome reassembly (Hirsch et al., Mol Ther 18(1):6-8, 2010). Split rAAV vector applications were developed based upon the finding that rAAV genomes naturally concatemerize in the cell post-transduction and are substrates for enhanced homologous recombination (HR) (Hirsch et al., Mol Ther 18(1):6-8, 2010; Duan et al., J Virol 73(1):161-169, 1999; Duan et al., J Virol 72(11):8568-8577, 1998; Duan et al., Mol Ther 4(4):383-391, 2001; Halbert et al., Nat Biotechnol 20(7):697-701, 2002). This method involves "splitting" the large transgene into two separate vectors and upon co-transduction, intracellular large gene reconstruction via vector genome concatemerization occurs via HR or nonhomologous end joining (NHEJ). Within the split rAAV approaches there currently exist three strategies: overlapping, trans-splicing, and hybrid trans-splicing (Duan et al., Mol Ther 4(4):383-391, 2001; Halbert et al., Nat Biotechnol 20(7):697-701, 2002; Ghosh et al., Mol Ther 16(1):124-130, 2008; Ghosh et al., Mol Ther 15(4):750-755, 2007). The other major

  10. Carrying capacity in agriculture: environmental significance and some related patents.

    Science.gov (United States)

    da Silva, Alexandre M

    2009-06-01

    Agriculture is one of the most important and possibly the oldest economic activity developed by humans. This activity was developed extensively and is becoming more and more dependent on development of technologies. The goal of this manuscript was examining some patents related to technologies developed for improving crop yields. Such patents are mainly related to more efficient formulations of agrochemicals and management techniques of plants, cattle and natural resources. A brief comment is carried out about bioprospection and related problems, relating, for example the case of Cupuaçu. The article is concluded mentioning that the development of policies and management strategies that increase agricultural yield and simultaneously preserve or conserve natural resources should also be prioritized, because certainly this is the only way we have to get the real sustainability and to improve life quality abroad the world.

  11. Delivering Transgenic DNA Exceeding the Carrying Capacity of AAV Vectors

    Science.gov (United States)

    Hirsch, Matthew L.; Wolf, Sonya J.; Samulski, R.J.

    2016-01-01

    Gene delivery using recombinant adeno-associated virus (rAAV) has emerged to the forefront demonstrating safe and effective phenotypic correction of diverse diseases including hemophilia B and Leber’s congenital amaurosis. In addition to rAAV’s high efficiency of transduction and the capacity for long-term transgene expression, the safety profile of rAAV remains unsoiled in humans with no deleterious vector-related consequences observed thus far. Despite these favorable attributes, rAAV vectors have a major disadvantage preventing widespread therapeutic applications; as the AAV capsid is the smallest described to date, it cannot package “large” genomes. Currently, the packaging capacity of rAAV has yet to be definitively defined but is approximately 5 kb, which has served as a limitation for large gene transfer. There are two main approaches that have been developed to overcome this limitation, split AAV vectors, and fragment AAV (fAAV) genome reassembly (Hirsch et al., Mol Ther 18(1):6–8, 2010). Split rAAV vector applications were developed based upon the finding that rAAV genomes naturally concatemerize in the cell post-transduction and are substrates for enhanced homologous recombination (HR) (Hirsch et al., Mol Ther 18(1):6–8, 2010; Duan et al., J Virol 73(1):161–169, 1999; Duan et al., J Virol 72(11):8568–8577, 1998; Duan et al., Mol Ther 4(4):383–391, 2001; Halbert et al., Nat Biotechnol 20(7):697–701, 2002). This method involves “splitting” the large transgene into two separate vectors and upon co-transduction, intracellular large gene reconstruction via vector genome concatemerization occurs via HR or nonhomologous end joining (NHEJ). Within the split rAAV approaches there currently exist three strategies: overlapping, trans-splicing, and hybrid trans-splicing (Duan et al., Mol Ther 4(4):383–391, 2001; Halbert et al., Nat Biotechnol 20(7):697–701, 2002; Ghosh et al., Mol Ther 16(1):124–130, 2008; Ghosh et al., Mol Ther 15

  12. A Study on the Thermal Effect of the Current-Carrying Capacity of Embedded Underground Cable

    Directory of Open Access Journals (Sweden)

    LI Dewen

    2012-10-01

    Full Text Available The current paper aims to study embedded underground cable and the effect of temperature that surrounds it. Determining the carrying capacity of the cable is important to predict the temperature changesin the embedded pipe. Simulating the temperature field and the laying environment according to the IEC standard enables the calculation of the carrying capacity of the buried region. According to the theoryof heat transfer, the embedded pipe tube model temperature field should be coupled with a numerical model. The domain and boundary conditions of the temperature field should also be determined using the 8.7/15kV YJV 400 cable. In conducting numerical calculation and analysis using the temperature field model, the two-dimensional temperature distribution of the emission control area should be determined. The experimental results show that the simulation isconsistent with the IEC standard. Furthermore, in identifying the cable ampacity, the different seasons and different cable rows should be taken into account using the finite element method. Finally, theappropriate choice of root and circuit numbers of the cable will improve the cable’s the carrying capacity.

  13. On evolutionary stability of carrying capacity driven dispersal in competition with regularly diffusing populations.

    Science.gov (United States)

    Korobenko, L; Braverman, E

    2014-11-01

    Two competing populations in spatially heterogeneous but temporarily constant environment are investigated: one is subject to regular movements to lower density areas (random diffusion) while the dispersal of the other is in the direction of the highest per capita available resources (carrying capacity driven diffusion). The growth of both species is subject to the same general growth law which involves Gilpin-Ayala, Gompertz and some other equations as particular cases. The growth rate, carrying capacity and dispersal rate are the same for both population types, the only difference is the dispersal strategy. The main result of the paper is that the two species cannot coexist (unless the environment is spatially homogeneous), and the carrying capacity driven diffusion strategy is evolutionarily stable in the sense that the species adopting this strategy cannot be invaded by randomly diffusing population. Moreover, once the invasive species inhabits some open nonempty domain, it would spread over any available area bringing the native species diffusing randomly to extinction. One of the important technical results used in the proofs can be interpreted in the form that the limit solution of the equation with a regular diffusion leads to lower total population fitness than the ideal free distribution.

  14. Determination of foraging thresholds and effects of application on energetic carrying capacity for waterfowl.

    Science.gov (United States)

    Hagy, Heath M; Kaminski, Richard M

    2015-01-01

    Energetic carrying capacity of habitats for wildlife is a fundamental concept used to better understand population ecology and prioritize conservation efforts. However, carrying capacity can be difficult to estimate accurately and simplified models often depend on many assumptions and few estimated parameters. We demonstrate the complex nature of parameterizing energetic carrying capacity models and use an experimental approach to describe a necessary parameter, a foraging threshold (i.e., density of food at which animals no longer can efficiently forage and acquire energy), for a guild of migratory birds. We created foraging patches with different fixed prey densities and monitored the numerical and behavioral responses of waterfowl (Anatidae) and depletion of foods during winter. Dabbling ducks (Anatini) fed extensively in plots and all initial densities of supplemented seed were rapidly reduced to 10 kg/ha and other natural seeds and tubers combined to 170 kg/ha, despite different starting densities. However, ducks did not abandon or stop foraging in wetlands when seed reduction ceased approximately two weeks into the winter-long experiment nor did they consistently distribute according to ideal-free predictions during this period. Dabbling duck use of experimental plots was not related to initial seed density, and residual seed and tuber densities varied among plant taxa and wetlands but not plots. Herein, we reached several conclusions: 1) foraging effort and numerical responses of dabbling ducks in winter were likely influenced by factors other than total food densities (e.g., predation risk, opportunity costs, forager condition), 2) foraging thresholds may vary among foraging locations, and 3) the numerical response of dabbling ducks may be an inconsistent predictor of habitat quality relative to seed and tuber density. We describe implications on habitat conservation objectives of using different foraging thresholds in energetic carrying capacity models and

  15. Carrying capacity in arid rangelands during droughts: the role of temporal and spatial thresholds.

    Science.gov (United States)

    Accatino, F; Ward, D; Wiegand, K; De Michele, C

    2017-02-01

    Assessing the carrying capacity is of primary importance in arid rangelands. This becomes even more important during droughts, when rangelands exhibit non-equilibrium dynamics, and the dynamics of livestock conditions and forage resource are decoupled. Carrying capacity is usually conceived as an equilibrium concept, that is, the consumer density that can co-exist in long-term equilibrium with the resource. As one of the first, here we address the concept of carrying capacity in systems, where there is no feedback between consumer and resource in a limited period of time. To this end, we developed an individual-based model describing the basic characteristics of a rangeland during a drought. The model represents a rangeland composed by a single water point and forage distributed all around, with livestock units moving from water to forage and vice versa, for eating and drinking. For each livestock unit we implemented an energy balance and we accounted for the gut-filling effect (i.e. only a limited amount of forage can be ingested per unit time). Our results showed that there is a temporal threshold above which livestock begin to experience energy deficit and burn fat reserves. We demonstrated that such a temporal threshold increases with the number of animals and decreases with the rangeland conditions (amount of forage). The temporal threshold corresponded to the time livestock take to consume all the forage within a certain distance from water, so that the livestock can return to water for drinking without spending more energy than they gain within a day. In this study, we highlight the importance of a time threshold in the assessment of carrying capacity in non-equilibrium conditions. Considering this time threshold could explain contrasting observations about the influence of livestock number on livestock conditions. In case of private rangelands, the herd size should be chosen so that the spatial threshold equals (or exceeds) the length of the drought.

  16. A model to estimate aquaculture carrying capacity in three areas of the Philippines

    Directory of Open Access Journals (Sweden)

    Tarzan Legović

    2008-12-01

    Full Text Available A model was developed to estimate the production carrying capacity of water bodies based on nutrient inputs from aquaculture and other sources, flushing rates, and the risk of algal blooms for three different areas of the Philippines – Bolinao (marine site, Dagupan (brackishwater site and Taal Lake (freshwater site. The results suggest that aquaculture production in the Taal Lake was greater than the sustainable carrying capacity. Aquaculture structures in Bolinao were close to carrying capacity during average tidal exchange but greater than the carrying capacity during low tidal exchange and no winds.Aquaculture production in the Dagupan estuary has not overcome its carrying capacity even during low flow. However, during very low flow and no tidal flushing, carrying capacity has been overcome.

  17. Synchronisation of fertility with carrying capacity; an investigation using classical and agent based modeling

    Directory of Open Access Journals (Sweden)

    Hugh Crozier Murrell

    2013-05-01

    Full Text Available A generalized Verhulst model subject to seasonal change in both fertility rate and carrying capacity is outlined. Numerical solutions to the Verhulst equations are employed to obtain optimal fertility rate phase shift with respect to carrying capacity. Possible natural selection for a preferred season of conception is investigated using agent based simulations. Both experiments indicate that synchronization of fertility rate to environment carrying capacity is beneficial to species survival.

  18. Research on Carrying Capacity of Water Resource Based on Multi-reservoir Regulation

    OpenAIRE

    Liu Renyuan; Li Lei; Li Hua; Huang Qiang

    2013-01-01

    Analyze the level of Carrying Capacity of Water Resources; evaluate the condition of e region social, economic and ecological environment comprehensive and sustainable development. This study is based on analyzing the meaning of water resources carrying capacity, take water resources of the Midwest of Shenzhen City an example., by the way of the “Coordinated and sustainable development” theory, found the model of the Carrying Capacity of Water Resources, Calculated and analyzed. Water efficie...

  19. Effects of a Fluctuating Carrying Capacity on the Generalized Malthus-Verhulst Model

    OpenAIRE

    Héctor Calisto; Chandía, Kristopher J.; Mauro Bologna

    2014-01-01

    We consider a generalized Malthus-Verhulst model with a fluctuating carrying capacity and we study its effects on population growth. The carrying capacity fluctuations are described by a Poissonian process with an exponential correlation function. We will find an analytical expression for the average of a number of individuals and show that even in presence of a fluctuating carrying capacity the average tends asymptotically to a constant quantity.

  20. Effects of a Fluctuating Carrying Capacity on the Generalized Malthus-Verhulst Model

    Directory of Open Access Journals (Sweden)

    Héctor Calisto

    2014-01-01

    Full Text Available We consider a generalized Malthus-Verhulst model with a fluctuating carrying capacity and we study its effects on population growth. The carrying capacity fluctuations are described by a Poissonian process with an exponential correlation function. We will find an analytical expression for the average of a number of individuals and show that even in presence of a fluctuating carrying capacity the average tends asymptotically to a constant quantity.

  1. The Analysis and Calculation Method of Urban Rail Transit Carrying Capacity Based on Express-Slow Mode

    Directory of Open Access Journals (Sweden)

    Xiaobing Ding

    2016-01-01

    Full Text Available Urban railway transport that connects suburbs and city areas is characterized by uneven temporal and spatial distribution in terms of passenger flow and underutilized carrying capacity. This paper aims to develop methodologies to measure the carrying capacity of the urban railway by introducing a concept of the express-slow mode. We first explore factors influencing the carrying capacity under the express-slow mode and the interactive relationships among these factors. Then we establish seven different scenarios to measure the carrying capacity by considering the ratio of the number of the express trains and the slow trains, the station where overtaking takes place, and the number of overtaking maneuvers. Taking Shanghai Metro Line 16 as an empirical study, the proposed methods to measure the carrying capacity under different express-slow mode are proved to be valid. This paper contributes to the literature by remodifying the traditional methods to measure the carrying capacity when different express-slow modes are applied to improve the carrying capacity of the suburban railway.

  2. Review on the Evaluation System of Public Safety Carrying Capacity about Small Town Community

    Institute of Scientific and Technical Information of China (English)

    Ming; SUN; Tianyu; ZHU

    2014-01-01

    Recently,small town community public safety problem has been increasingly highlighted,but its research is short on public safety carrying capacity. Through the investigation and study of community public safety carrying capacity,this paper analyzes the problem of community public safety in our country,to construct index evaluation system of public safety carrying capacity in small town community. DEA method is used to evaluate public safety carrying capacity in small town community,to provide scientific basis for the design of support and standardization theory about small town community in public safety planning.

  3. Risk Analysis on Groundwater Resources Carrying Capacity Based on Blind Number Theory

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji; YU Sujun

    2007-01-01

    Blind numbers of evaluation indices about groundwater resources carrying capacity are defined from the concomitancy of randomness, fuzziness, grey property and unascertainment of groundwater system.Based on fuzzy theory, a comprehensive evaluation model on groundwaterresources carrying capacity is constructed with blind information. Then arisk assessment model of surcharge about groundwater resources carryingcapacity is established on blind reliability theory. The probable value"*"'matrix of fuzzy membership degree about carrying capacity corresponding to each judgment level can be obtained with the aid of blind algorithm as well as the subjective reliability "×" matrix. And then a graph of"groundwater carrying capacity v.s. accumulative reliability" can be gained.Based on the graph, fuzzy membership degree of groundwater resourcescarrying capacity to each judgment level under different risk probabilitycan be got. Thus, a comparatively reasonable judgment to groundwaterresources carrying capacity might be obtained, with comprehensive analysis to the state of society, economy technology and ecology.

  4. Carry

    DEFF Research Database (Denmark)

    Koijen, Ralph S.J.; Moskowitz, Tobias J.; Heje Pedersen, Lasse;

    that include global equities, global bonds, currencies, commodities, US Treasuries, credit, and equity index options. This predictability underlies the strong returns to "carry trades" that go long high-carry and short low-carry securities, applied almost exclusively to currencies, but shown here...

  5. The application of a phosphorus mass balance model for estimating the carrying capacity of Lake Kariba

    OpenAIRE

    MHLANGA, Lindah; MHLANGA, Wilson; MWERA, Paul

    2013-01-01

    The aim of this study was to use an empirical mass balance equation to estimate the carrying capacity of Lake Kariba, where cage culture for Nile tilapia Oreochromis niloticus has been practiced since 1996. The carrying capacity for the lake was estimated at 33.2 × 103 t per year using the Dillon-Rigler phosphorus budget model.

  6. Noise-Induced Transitions in a Population Growth Model Based on Size-Dependent Carrying Capacity

    Directory of Open Access Journals (Sweden)

    Neeme Lumi

    2014-01-01

    Full Text Available The stochastic dynamics of a population growth model with size-dependent carrying capacity is considered. The effect of a fluctuating environment on population growth is modeled as a multiplicative dichotomous noise. At intermediate values of population size the deterministic counterpart of the model behaves similarly to the Von Foerster model for human population, but at small and very large values of population size substantial differences occur. In the stochastic case, an exact analytical solution for the stationary probability distribution is found. It is established that variation of noise correlation time can cause noise-induced transitions between three different states of the system characterized by qualitatively different behaviors of the probability distributions of the population size. Also, it is shown that, in some regions of the system parameters, variation of the amplitude of environmental fluctuations can induce single unidirectional abrupt transitions of the mean population size.

  7. Phenomenological approach to describe logistic growth and carrying capacity-dependent growth processes

    Indian Academy of Sciences (India)

    DIBYENDU BISWAS; SWARUP PORIA; SANKAR NARAYAN PATRA

    2016-11-01

    In this communication, different classes of phenomenological universalities of carrying capacity dependent growth processes have been proposed. The logistic as well as carrying capacity-dependent West-type allometry-based biological growths can be explained in this proposed framework. It is shown that logistic and carrying capacity-dependent West-type growths are phenomenologically identical in nature. However, there is a difference between them in terms of coefficients involved in the phenomenological descriptions. Involuted Gompertz function, used to describe biological growth processes undergoing atrophy or a demographic and economic system undergoing involution or regression, can be addressed in this proposed environment-dependent description. It is also found phenomenologically that the energy intake of an organism depends on carrying capacity whereas metabolic cost does not depend on carrying capacity. In addition, some other phenomenologicaldescriptions have been examined in this proposed framework and graphical representations of variation of different parameters involved in the description are executed.

  8. Research on Carrying Capacity of Water Resource Based on Multi-reservoir Regulation

    Directory of Open Access Journals (Sweden)

    Liu Renyuan

    2013-12-01

    Full Text Available Analyze the level of Carrying Capacity of Water Resources; evaluate the condition of e region social, economic and ecological environment comprehensive and sustainable development. This study is based on analyzing the meaning of water resources carrying capacity, take water resources of the Midwest of Shenzhen City an example., by the way of the “Coordinated and sustainable development” theory, found the model of the Carrying Capacity of Water Resources, Calculated and analyzed. Water efficiency coefficients are different in different states, the Carrying Capacity of Water Resources is different too. the water resources in the Midwest of Shenzhen City can only meet now this stage (2010 Urban water demand, meanwhile people of over loading in there are also constantly increasing, In the future, Water requirement of Shenzhen Midwest cities must increase Dongjiang water and west diversion works of Shen Zhen, in order to enhance Carrying Capacity of Water Resources of the area.

  9. Comparative analysis of environmental carrying capacity of the Bohai Sea Rim area in China.

    Science.gov (United States)

    Lin, Lu; Liu, Yi; Chen, Jining; Zhang, Tianzhu; Zeng, Siyu

    2011-11-01

    Environmental carrying capacity is an essential metric for measuring regional sustainability. Although the term "carrying capacity" has been applied for over a century, the concept definition, quantitative methods and comprehensive evaluation remain arguable. This study analyzed the carrying capacity of four environmental elements, including water resources, air, surface water and offshore sea, and integrated them into a comprehensive index to represent overall regional profiles of resources and environment. The method was then applied to thirteen municipalities in the Bohai Sea Rim area, one of the most rapidly developing regions in transition China. The results show that the comprehensive environmental carrying capacity of the municipalities in the south sub-region were largest in 2007, while that of the west municipalities were lowest. The regional economic development exceeded the overall environmental carrying capacity by 36% and the west sub-region area deserves overwhelming attention for future industrial allocation.

  10. Rural Settlement Development and Environment Carrying Capacity Changes in Progo River Basin

    Directory of Open Access Journals (Sweden)

    Su Ritohardoyo

    2016-12-01

    Full Text Available Generally the broader rural settlement the heavier population pressure on agricultural land. It indicates that carrying capacity of the rural environment threatened lower. The spatial distribution of the threat in a river basin is quite important as one of the river basin management inputs. Therefore, this article aims at exposing result of research about influence rural population growth and rural settlement land changes to environment carrying capacity. This research was carried out in the rural area in Progo river basin consists 56 sub districts (34 sub districts part of Jawa Tengah Province, and 22 sub districts part of Yogyakarta Special Region. The whole sub districts are such as unit analysis, and research method is based on secondary data analysis. Several data consist Districts Region in Figure 1997 and 2003 (Temanggung, Magelang, Kulon Progo, Sleman and Bantul such as secondary data analysis. Data analysis employs of frequency and cross tabulation, statistics of regression and test. Result of the research shows that population growth of the rural areas in Progo river basin are about 0.72% annum; or the household growth about 3.15% annum as long as five years (1996-2003. Spatial distribution of the population growth in the upper part of the Progo river basin is higher than in the middle and lower part of the basin. The number proportion of farmer in every sub district area in this river basin have increased from 69.95% in 1997 to 70.81% in the year of 2003. It means that work opportunities broadening are still sluggish. However, the number proportion of farmers in the upper part of the Progo river basin is lower than in the middle and lower part of the basin. The rates of settlement land areas changes (0.32 ha/annum as long as five years (1997-2003 is not as fast as the rates of agricultural land areas changes (0.47 ha/annum. Spatial land settlement areas changes in the lower (6.1 ha/annum and middle parts (2.4 ha/annum faster than

  11. Estimating Recreational Carrying Capacity of Gheisary Protected Area in Chaharmahal & Bakhtiari Province

    OpenAIRE

    Sheikh, A; Jafari, A.; Setoodeh, A

    2014-01-01

    It is now certain that to ensure a long term sustainable development, protected areas, the favored destinations for ecotourism, required a well written planning management. Each destination however has limited capability which is called “carrying capacity” to invite visitors. Physical, real (ecological) and effective (manageable) are different kinds of carrying capacity. The current study presented these varieties of carrying capacities for Gheisary protected area, stretched over 10,000 ha in...

  12. [Evaluation of land resources carrying capacity of development zone based on planning environment impact assessment].

    Science.gov (United States)

    Fu, Shi-Feng; Zhang, Ping; Jiang, Jin-Long

    2012-02-01

    Assessment of land resources carrying capacity is the key point of planning environment impact assessment and the main foundation to determine whether the planning could be implemented or not. With the help of the space analysis function of Geographic Information System, and selecting altitude, slope, land use type, distance from resident land, distance from main traffic roads, and distance from environmentally sensitive area as the sensitive factors, a comprehensive assessment on the ecological sensitivity and its spatial distribution in Zhangzhou Merchants Economic and Technological Development Zone, Fujian Province of East China was conducted, and the assessment results were combined with the planning land layout diagram for the ecological suitability analysis. In the Development Zone, 84.0% of resident land, 93.1% of industrial land, 86.0% of traffic land, and 76. 0% of other constructive lands in planning were located in insensitive and gently sensitive areas, and thus, the implement of the land use planning generally had little impact on the ecological environment, and the land resources in the planning area was able to meet the land use demand. The assessment of the population carrying capacity with ecological land as the limiting factor indicated that in considering the highly sensitive area and 60% of the moderately sensitive area as ecological land, the population within the Zone in the planning could reach 240000, and the available land area per capita could be 134.0 m2. Such a planned population scale is appropriate, according to the related standards of constructive land.

  13. Hyperspectral Biofilm Classification Analysis for Carrying Capacity of Migratory Birds in the South Bay Salt Ponds

    Science.gov (United States)

    Ketron, T.; Hsu, W.; Kuss, A. M.; Nguyen, A.; Remar, A. C.; Newcomer, M. E.; Fleming, E.; Bebout, L.; Bebout, B.; Detweiler, A. M.; Skiles, J. W.

    2011-12-01

    Tidal marshes are highly productive ecosystems that support migratory birds as roosting and over-wintering habitats on the Pacific Flyway. Microphytobenthos, or more commonly 'biofilms' contribute significantly to the primary productivity of wetland ecosystems, and provide a substantial food source for macroinvertebrates and avian communities. In this study, biofilms were characterized based on taxonomic classification, density differences, and spectral signatures. These techniques were then applied to remotely sensed images to map biofilm densities and distributions in the South Bay Salt Ponds and predict the carrying capacity of these newly restored ponds for migratory birds. The GER-1500 spectroradiometer was used to obtain in situ spectral signatures for each density-class of biofilm. The spectral variation and taxonomic classification between high, medium, and low density biofilm cover types was mapped using in-situ spectral measurements and classification of EO-1 Hyperion and Landsat TM 5 images. Biofilm samples were also collected in the field to perform laboratory analyses including chlorophyll-a, taxonomic classification, and energy content. Comparison of the spectral signatures between the three density groups shows distinct variations useful for classification. Also, analysis of chlorophyll-a concentrations show statistically significant differences between each density group, using the Tukey-Kramer test at an alpha level of 0.05. The potential carrying capacity in South Bay Salt Ponds is estimated to be 250,000 birds.

  14. Hyperspectral Biofilm Classification Analysis for Carrying Capacity of Migratory Birds in the South Bay Salt Ponds

    Science.gov (United States)

    Hsu, Wei-Chen; Kuss, Amber Jean; Ketron, Tyler; Nguyen, Andrew; Remar, Alex Covello; Newcomer, Michelle; Fleming, Erich; Debout, Leslie; Debout, Brad; Detweiler, Angela; hide

    2011-01-01

    Tidal marshes are highly productive ecosystems that support migratory birds as roosting and over-wintering habitats on the Pacific Flyway. Microphytobenthos, or more commonly 'biofilms' contribute significantly to the primary productivity of wetland ecosystems, and provide a substantial food source for macroinvertebrates and avian communities. In this study, biofilms were characterized based on taxonomic classification, density differences, and spectral signatures. These techniques were then applied to remotely sensed images to map biofilm densities and distributions in the South Bay Salt Ponds and predict the carrying capacity of these newly restored ponds for migratory birds. The GER-1500 spectroradiometer was used to obtain in situ spectral signatures for each density-class of biofilm. The spectral variation and taxonomic classification between high, medium, and low density biofilm cover types was mapped using in-situ spectral measurements and classification of EO-1 Hyperion and Landsat TM 5 images. Biofilm samples were also collected in the field to perform laboratory analyses including chlorophyll-a, taxonomic classification, and energy content. Comparison of the spectral signatures between the three density groups shows distinct variations useful for classification. Also, analysis of chlorophyll-a concentrations show statistically significant differences between each density group, using the Tukey-Kramer test at an alpha level of 0.05. The potential carrying capacity in South Bay Salt Ponds is estimated to be 250,000 birds.

  15. Ecological Carrying Capacity in Beijing Mountainous Areas Taking Fangshan District as an Example

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] The aim was to investigate ecological carrying capacity of Fangshan District in Beijing. [Method] Ecological footprint and carrying capacity of Fangshan District in 2007 and 2008 were analyzed with ecological footprint model and the difference between ecological footprint and carrying capacity there was con- cluded. Furthermore, an assessment was made on relation between Fangshan de- velopment with local ecological carrying capacity to evaluate sustainable development of Fangshan District. [Result] Fangshan District is of lightly ecological deficit; ecologi- cal footprint per capita in 2007-2008 was deficit and tended to expand. Two meth- ods are available to reduce ecological :deficit, including reduction of ecological foot- print and increase of carrying capacity. In general, supply and demand of carrying capacity in Fangshan are better, though with some problems. It is necessary to fur- ther develop related industries to final eliminate ecological deficit in order to achieve ecological conservation-orientation and sustainable development of Fangshan District. [Conclusion] The research provides theoretical references for overall evaluation on eco- logical carrying capacity of Fangshan District.

  16. A Novel Evaluation algorithm of Urban Comprehensive Carrying Capacity Index System in Northwest China:Lanzhou city as a example

    Science.gov (United States)

    Li, Jing; Lei, Song; Ling, Ma

    2016-06-01

    With the rapid growth of the urban population and quick expansion of urban dimensions, the affecting urban development constraints of urban carrying capacity has increasingly been attracting people's attention. However, the effective synthesization of urban resources carrying capacity, urban environmental carrying capacity, economic carrying capacity, society carrying capacity and traffic carrying capacity hardly acted as an urban comprehensive carrying capacity evaluation system. In this paper, the novel comprehensive index system of urban resources carrying capacity, urban environmental carrying capacity, economic carrying capacity, society carrying capacity and traffic carrying capacity was used for analyzing and evaluating urban comprehensive carrying capacity. Firstly, the standardization of evaluation index was constructed in the urban comprehensive carrying capacity index system. In addition, the past decade data from 2002 to 2011 was analyzed and evaluated in the weighted index system. Finally, the influence mechanism of various carrying capacity factors on urban comprehensive carrying capacity was investigated in Lanzhou. Experimental results can be summarized that the variation tendency of urban comprehensive carrying capacity was the annual increase of levels and the promotion countermeasure was put forward with congenital restricting factors and acquired restricting factors.

  17. Impact of Flexibility Options on Grid Economic Carrying Capacity of Solar and Wind: Three Case Studies

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Novacheck, Joshua [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Lab. (NREL), Golden, CO (United States); O' Connell, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-12-01

    In this study, we attempt to quantify the benefits of various options of grid flexibility by measuring their impact on two measures: economic carrying capacity and system costs. Flexibility can increase economic carrying capacity and reduce overall system costs. In some cases, options that provide a limited increase in economic carrying capacity can provide significant operational savings, thus demonstrating the need to evaluate flexibility options using multiple metrics. The value of flexibility options varies regionally due to different generation mixes and types of renewables. The more rapid decline in PV value compared to wind makes PV more dependent on adding flexibility options, including transmission and energy storage.

  18. Quantifying spatially derived carrying capacity occupation: Framework for characterisation modelling and application to terrestrial acidification

    DEFF Research Database (Denmark)

    Bjørn, Anders; Margni, M.; Bulle, C.

    *year. This metric resembles that of the ecological footprint method and may be compared to the availability of land or water. The framework was applied to the terrestrial acidification impact category. The geochemical steady-state model PROFILE was used to quantify carrying capacities as deposition levels......The popularity of the ecological footprint method and the planetary boundaries concept shows an increasing interest among decision makers in comparing environmental impacts to carrying capacities of natural systems. Recently carrying capacity-based normalisation references were developed for impact...

  19. Meta-analysis of carrying capacity and abundance-area relationships in marine fish species

    DEFF Research Database (Denmark)

    Mantzouni, Irene

    fish produced by spawners in a given year which subsequently grow and survive to become vulnerable to fishing gear) have reacted to temperature fluctuations, and in particular to extremes of temperature, throughout the north Atlantic. Meta-analytical methods based on effect sizes were employed......Knowledge on the carrying capacity and the abundance-area relationships of fish is critical to evaluate the impacts of exploitation and climate on the sustainability and also the recovery potential of the populations. Of particular interest is climate change, inducing major consequences...... for population dynamics and life histories of marine biota as it progresses in the 21st century. In the present PhD project, a variety of meta-analytic methods was employed to statistically combine data across the north Atlantic distributions of 3 commercially and ecologically important species; cod (Gadus...

  20. 首都圈人口空间分布优化策略--基于土地资源承载力估测%Optimization Strategy of Population Distribution in Capital Metropolitan Region:Based on Land Resources Carrying Capacity Evaluation

    Institute of Scientific and Technical Information of China (English)

    彭文英; 刘念北

    2015-01-01

    采用单项指标估测,分析了首都圈土地资源人口承载及其限制性,提出了人口空间分布优化策略。首都圈水资源及建设用地生态适宜量限制了人口承载能力,京津土地资源人口承载力已基本达到饱和,环京津的冀东、冀中地区承载潜力还较大,冀北地区应紧缩开发空间而拓展生态空间。首都圈土地资源开发利用及人口发展战略分区为:首都圈北部生态屏障建设区,人口限制发展;中部都市功能优化区,人口控制增长;东部人口产业沿海集聚区,人口鼓励增长;南部绿色空间优化区,人口适度增长。首都圈的健康发展,应实施差异化的土地利用及人口发展政策,整体提升人口承载力,并加大区域统筹力度,科学、合理地引导人口的空间分流和聚集。%Relieving the pressure of megacities’central urban area is a hot issue on regional development and urban economy studies in our country, and it is an important national population development strategy to active-ly promote the economically developed urbanized area where the resources and environmental carrying capaci-ty is strong to absorb and cluster population. Capital metropolitan region of China in this study, including Bei-jing and Tianjin municipalities and 7 cities in Hebei Province around Beijing, such as Baoding, Qinhuangdao, Langfang, Cangzhou, Chengde, Zhangjiakou and Tangshan. The resources and environment, population distri-bution, urban economy development level have obvious differences among cities. Therefore, it is of important theoretical and practical significance to study the population space distribution optimization on the basis of re-sources and environment carrying capacity of the metropolitan region. On the basis of land resources utilization and its population carrying capacity situation, by estimating the population carrying capacity of construction land and water resources and evaluating

  1. Carrying Capacity Model Applied to Coastal Ecotourism of Baluran National Park, Indonesia

    Science.gov (United States)

    Armono, H. D.; Rosyid, D. M.; Nuzula, N. I.

    2017-07-01

    The resources of Baluran National Park have been used for marine and coastal ecotourism. The increasing number of visitors has led to the increasing of tourists and its related activities. This condition will cause the degradation of resources and the welfare of local communities. This research aims to determine the sustainability of coastal ecotourism management by calculating the effective number of tourists who can be accepted. The study uses the concept of tourism carrying capacity, consists the ecological environment, economic, social and physical carrying capacity. The results of the combined carrying capacity analysis in Baluran National Park ecotourism shows that the number of 3.288 people per day (151.248 tourists per year) is the maximum number of accepted tourists. The current number of tourist arrivals is only 241 people per day (87.990 tourists per year) which is far below the carrying capacity.

  2. Spawner-recruit relationships and fish stock carrying capacity in aquatic ecosystems

    DEFF Research Database (Denmark)

    MacKenzie, Brian; Myers, R.A.; Bowen, K.G.

    2003-01-01

    Few marine ecologists have addressed important questions about the relative productivity and carrying capacity of different ecosystems required to support fish populations. Whereas many researchers have investigated interannual variability in recruitment within a stock, we asked whether...

  3. Recreation carrying capacity estimations to support beach management at Praia de Faro, Portugal

    OpenAIRE

    Zacarias, D. A.; Williams, Allan T.; Newton, Alice

    2011-01-01

    The purpose of this research paper is to outline the theory and practice of tourism carrying capacity assessment and its relevance as a management tool for coastal management. Based on the Tourism Carrying Capacity Assessment for Protected Areas Framework and the Image Capture Technique associated with the PAOT (people at one time) approach, this paper explores Praia de Faro as the study area and attempts to assess the optimum number of people that should be allowed without jeopar...

  4. Theoretical Research of the Urban Comprehensive Carrying Capacity in the Epoch of Urbanization

    OpenAIRE

    Li Changliang; Lian Lina

    2012-01-01

    Conventional wisdom suggests that ecological factors are prominent constraints of cities in the urbanization process. By contrast, this article provides a fresh conception of the urban comprehensive carrying capacity in the context of ecosystem, economy and social dimensions. Based on in-depth analysis, the author makes out a list of informative area-based indicators in three differentiated layers and the findings are that the urban comprehensive carrying capacity is an entanglement of three ...

  5. The Carrying Capacity of Public Wild Land Recreation Areas: Evaluation of Alternative Measures

    Science.gov (United States)

    Greist, David A.

    1976-01-01

    Carrying capacity (the use level at which total satisfactions or benefits are mazimized) is not equatable to highest-use levels, since some visitors to recreational areas desire solitude and undisturbed environment--for these, an alternative definition for "capacity" should take into consideration the use level demanded after considering costs.…

  6. Evaluating Beijing's human carrying capacity from the perspective of water resource constraints.

    Science.gov (United States)

    Zhang, Yingxuan; Chen, Min; Zhou, Wenhua; Zhuang, Changwei; Ouyang, Zhiyun

    2010-01-01

    As the demands on limited water resources intensify, concerns are being raised about the human carrying capacity of these resources. However, few researchers have studied the carrying capacity of regional water resources. Beijing, the second-largest city in China, faces a critical water shortage that will limit the city's future development. We developed a method to quantify the carrying capacity of Beijing's water resources by considering water-use structures based on the proportions of water used for agricultural, industrial, and domestic purposes. We defined a reference structure as 45:22:33 (% of total, respectively), an optimized structure as 40:20:40, and an ideal structure as 50:15:35. We also considered four domestic water quotas: 55, 75, 95, and 115 m3/(person x yr). The urban carrying capacity of 10-12 million was closest to Beijing's actual 2003 population for all three water-use structures with urban domestic water use of 75 m3/(person x yr). However, after accounting for our underlying assumptions, the adjusted carrying capacity is closer to 5-6 million. Thus, Beijing's population in 2003 was almost twice the adjusted carrying capacity. Based on this result, we discussed the ecological and environmental problems created by Beijing's excessive population and propose measures to mitigate these problems.

  7. Introducing carrying capacity-based normalisation in LCA: framework and development of references at midpoint level

    DEFF Research Database (Denmark)

    Bjørn, Anders; Hauschild, Michael Zwicky

    2015-01-01

    capacity of a reference region divided by its population and thus describes the annual personal share of the carrying capacity.The developed references can be applied to indicator results obtained using commonly applied characterisation models in LCIA. The European NR are generally lower than the global NR...... ozone formation and soil quality were found to exceed carrying capacities several times.The developed carrying capacity-based normalisation references offer relevant supplementary reference information to the currently applied references based on society’s background interventions by supporting...... an evaluation of the environmental sustainability of product systems on an absolute scale.Challenges remain with respect to spatial variations to increase the relevance of the normalisation references for impact categories that function at the local or regional scale. The sensitivity of NR to different choices...

  8. The study of environmental carrying capacity for sustainable tourism in Telaga Warna Telaga Pengilon Nature Park, Dieng Plateu, Central Java

    Science.gov (United States)

    Melat Aryasa, Alexander; Nur Bambang, Azis; Muhammad, Fuad

    2017-06-01

    The increasing in quantity of the tourists visiting Telaga Warna Telaga Pengilon Nature Park, Dieng Plateau, Central Java, can cause a potential threat toward the conservation sustainability of the tourist attraction and the surrounding area. The utilization of conservation area for tourist attraction has to be carried out based on the principal of Environmental Carrying Capacity so that it will not affect the ecosystem. This study aims to determine the value of Telaga Warna Telaga Pengilon Nature Park environmental carrying capacity as a conservation area used for tourism activities. The environmental carrying capacities calculated in this study were physical carrying capacity, real carrying capacity, and effective carrying capacity. Results of this research show that the physical carrying capacity of The Telaga Warna Telaga Pengilon Nature Park was 31,302 visitors, the real capacity was 869 visitors/day and the effective carrying capacity was 579 visitors/day. Thus, the sustainable tourism development strategy is needed to manage the everlasting natural resources.

  9. Measurement and assessment of carrying capacity of the environment in Ningbo, China.

    Science.gov (United States)

    Liu, R Z; Borthwick, Alistair G L

    2011-08-01

    Carrying Capacity of the Environment (CCE) provides a useful measure of the sustainable development of a region. Approaches that use integrated assessment instead of measurement can lead to misinterpretation of sustainable development because of confusion between Environmental Stress (ES) indexes and CCE indexes, and the selection of over-simple linear plus models. The present paper proposes a comprehensive measurement system for CCE which comprises models of natural resources capacity, environmental assimilative capacity, ecosystem services capacity, and society supporting capacity. The corresponding measurable indexes are designed to assess CCE using a carrying capacity surplus ratio model and a vector of surplus ratio of carrying capacity model. The former aims at direct comparison of ES and CCE based on the values of basic indexes, and the latter uses a Euclidean vector to assess CCE states. The measurement and assessment approaches are applicable to Strategic Environmental Assessment (SEA) and environmental planning and management. A case study is presented for Ningbo, China, whereby all the basic indexes of ECC are measured and the CCE states assessed for 2005 and 2010.

  10. Evaluation of Ecological Carrying Capacity of Henan Province under the Sustainable Development

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Based on the overview of social economy of Henan Province,I probe into the concept and evaluation of ecological carrying capacity.By using the ecological footprint analysis and the data of various kinds of land supply of Henan Province from 2000 to 2008,the ecological carrying capacity of Henan Province is analyzed.It is unveiled that inharmonious population,natural resources and economic resources affect the efficiency of the sustainable development of ecological carrying capacity of Henan Province;the underdeveloped economy of Henan Province impacts the sustainable development of ecological carrying capacity of Henan Province and the overburdened population lead to the insufficiency of ecological carrying capacity.Around protecting the threshold of ecological system,the countermeasures are put forward,which cover forming the idea of ecological economy and circular economy and promoting the transformation of economy growth mode;taking the development road of using resources intensively and performing the strategy of sustainable utilization of resources;strictly control population growth and strengthening people’s crisis awareness of resources and environment.

  11. Carrying capacity of U.S. agricultural land: Ten diet scenarios

    Directory of Open Access Journals (Sweden)

    Christian J. Peters

    2016-07-01

    Full Text Available Abstract Strategies for environmental sustainability and global food security must account for dietary change. Using a biophysical simulation model we calculated human carrying capacity under ten diet scenarios. The scenarios included two reference diets based on actual consumption and eight “Healthy Diet” scenarios that complied with nutritional recommendations but varied in the level of meat content. We considered the U.S. agricultural land base and accounted for losses, processing conversions, livestock feed needs, suitability of land for crops or grazing, and land productivity. Annual per capita land requirements ranged from 0.13 to 1.08 ha person-1 year-1 across the ten diet scenarios. Carrying capacity varied from 402 to 807 million persons; 1.3 to 2.6 times the 2010 U.S. population. Carrying capacity was generally higher for scenarios with less meat and highest for the lacto-vegetarian diet. However, the carrying capacity of the vegan diet was lower than two of the healthy omnivore diet scenarios. Sensitivity analysis showed that carrying capacity estimates were highly influenced by starting assumptions about the proportion of cropland available for cultivated cropping. Population level dietary change can contribute substantially to meeting future food needs, though ongoing agricultural research and sustainable management practices are still needed to assure sufficient production levels.

  12. Variation in local carrying capacity and the individual fate of bacterial colonizers in the phyllosphere.

    Science.gov (United States)

    Remus-Emsermann, Mitja N P; Tecon, Robin; Kowalchuk, George A; Leveau, Johan H J

    2012-04-01

    Using a phyllosphere model system, we demonstrated that the term 'carrying capacity', as it is commonly used in microbial ecology, needs to be understood as the sum of many 'local carrying capacities' in order to better explain and predict the course and outcome of bacterial colonization of an environment. Using a green fluorescent protein-based bioreporter system for the quantification of reproductive success (RS) in individual Erwinia herbicola cells, we were able to reconstruct the contribution of individual immigrants to bacterial population sizes on leaves. Our analysis revealed that plant foliage represents to bacteria an environment where individual fate is determined by the local carrying capacity of the site where an immigrant cell lands. With increasing inoculation densities, the RS of most immigrants declined, suggesting that local carrying capacity under the tested conditions was linked to local nutrient availability. Fitting the observed experimental data to an adapted model of phyllosphere colonization indicated that there might exist three types of sites on leaves, which differ in their frequency of occurrence and local carrying capacity. Specifically, our data were consistent with a leaf environment that is characterized by few sites where individual immigrants can produce high numbers of offspring, whereas the remainder of the leaf offered an equal number of sites with low and medium RS. Our findings contribute to a bottom-up understanding of bacterial colonization of leaf surfaces, which includes a quantifiable role of chance in the experience at the individual level and in the outcome at the population level.

  13. Modelling of carrying capacity in National Park - Fruška Gora (Serbia case study

    Directory of Open Access Journals (Sweden)

    Vujko Aleksandra

    2017-03-01

    Full Text Available Negative effects of tourism development in a destination are usually the consequence of the high concentration of tourists, accommodation facilities and the activities that are practiced in a relatively restricted area. One of the most important measures to protect the areas is to calculate the maximum number of tourists that can simultaneously reside in a region, i.e. the determination of the carrying capacity. This paper outlines a method for determining carrying capacity based on zoning of environmental resources and zoning within a region. The paper argues for a return to the idea of identifying maximum appropriate number of users. The main hypothesis of the paper is based on the statement that the development of tourism in Fruška Gora (Mountain National Park in Northern Serbia must be in accordance with the basic principles of sustainability, including the determination of carrying capacity. The main research goal was to show the opinion of local residents about the uncontrolled development of tourism, and to determine the carrying capacity in four sports and recreational zones of the mountain. The carrying capacity of the area is calculated by Lavery and Stanev formulas.

  14. The evolution of carrying capacity in constrained and expanding tumour cell populations.

    Science.gov (United States)

    Gerlee, Philip; Anderson, Alexander R A

    2015-08-12

    Cancer cells are known to modify their micro-environment such that it can sustain a larger population, or, in ecological terms, they construct a niche which increases the carrying capacity of the population. It has however been argued that niche construction, which benefits all cells in the tumour, would be selected against since cheaters could reap the benefits without paying the cost. We have investigated the impact of niche specificity on tumour evolution using an individual based model of breast tumour growth, in which the carrying capacity of each cell consists of two components: an intrinsic, subclone-specific part and a contribution from all neighbouring cells. Analysis of the model shows that the ability of a mutant to invade a resident population depends strongly on the specificity. When specificity is low selection is mostly on growth rate, while high specificity shifts selection towards increased carrying capacity. Further, we show that the long-term evolution of the system can be predicted using adaptive dynamics. By comparing the results from a spatially structured versus well-mixed population we show that spatial structure restores selection for carrying capacity even at zero specificity, which poses a solution to the niche construction dilemma. Lastly, we show that an expanding population exhibits spatially variable selection pressure, where cells at the leading edge exhibit higher growth rate and lower carrying capacity than those at the centre of the tumour.

  15. Modelling of carrying capacity in National Park - Fru\\vska Gora (Serbia) case study

    Science.gov (United States)

    Vujko, Aleksandra; Plavša, Jovan; Petrović, Marko D.; Radovanović, Milan; Gajić, Tamara

    2017-03-01

    Negative effects of tourism development in a destination are usually the consequence of the high concentration of tourists, accommodation facilities and the activities that are practiced in a relatively restricted area. One of the most important measures to protect the areas is to calculate the maximum number of tourists that can simultaneously reside in a region, i.e. the determination of the carrying capacity. This paper outlines a method for determining carrying capacity based on zoning of environmental resources and zoning within a region. The paper argues for a return to the idea of identifying maximum appropriate number of users. The main hypothesis of the paper is based on the statement that the development of tourism in Fru\\vska Gora (Mountain) National Park in Northern Serbia must be in accordance with the basic principles of sustainability, including the determination of carrying capacity. The main research goal was to show the opinion of local residents about the uncontrolled development of tourism, and to determine the carrying capacity in four sports and recreational zones of the mountain. The carrying capacity of the area is calculated by Lavery and Stanev formulas.

  16. An Alternative Approach for High Speed Railway Carrying Capacity Calculation Based on Multiagent Simulation

    Directory of Open Access Journals (Sweden)

    Mo Gao

    2016-01-01

    Full Text Available It is a multiobjective mixed integer programming problem that calculates the carrying capacity of high speed railway based on mathematical programming method. The model is complex and difficult to solve, and it is difficult to comprehensively consider the various influencing factors on the train operation. The multiagent theory is employed to calculate high speed railway carrying capacity. In accordance with real operations of high speed railway, a three-layer agent model is developed to simulate the operating process of high speed railway. In the proposed model, railway network agent, line agent, station agent, and train agent are designed, respectively. To validate the proposed model, a case study is performed for Beijing–Shanghai high speed railway by using NetLogo software. The results are consistent with the actual data, which implies that the proposed multiagent method is feasible to calculate the carrying capacity of high speed railway.

  17. Estimating the carrying capacity of green mussel cultivation by using net nutrient removal model.

    Science.gov (United States)

    Srisunont, Chayarat; Babel, Sandhya

    2016-11-15

    This study aims to evaluate the nutrient removal potential and carrying capacity of green mussel cultivation by using the mass balance model. The developed model takes into consideration the green mussel growth rate, density and chlorophyll a concentration. The data employed in this study were based on culture conditions at Sriracha Fisheries Research Station, Thailand. Results show that net nutrient removal by green mussel is 3302, 380, and 124mg/year/indv for carbon, nitrogen, and phosphorus respectively. The carrying capacity of green mussel cultivation was found to be 300indv/m(2) based on chlorophyll a concentration which will not release phosphorus in the water environment beyond the standard (45μg-PO4(-3)-P/L). Higher chlorophyll a concentration results in lowered green mussel carrying capacity. This model can assist farm operators with possible management strategies for a sustainable mussel cultivation and protection of the marine environment.

  18. Conditions for the management of carrying capacity in the parks of Parks&Benefits

    DEFF Research Database (Denmark)

    Brandt, Jesper; Holmes, Esbern

    2011-01-01

    Growth in the number of visitors is an upcoming problem in nature parks. Nature parks are at the same time facing increasing demand, falling public appropriations and receding focus on their conservation functions. To ensure a balancing of nature protection and economic utilization the concept...... of carrying capacity has received increasing attention among park-authorities all over the world. Carrying capacities understood as limits or standards not to be exceeded to protect a supporting landscape system are not scientifically determined sizes. They are a result of political decision processes among...... stakeholders, balancing use and protection preferably based on scientific and/or experiential cognition. The conditions for the management of carrying capacity for the 8 nature parks in the EC Baltic Project Parks&Benefits are analysed in the report. 1. Part focus on the methodology, concentrated...

  19. Self-adjustment of Carrying Capacity of Concrete Embedded with CFRC

    Institute of Scientific and Technical Information of China (English)

    Wu YAO

    2006-01-01

    By heating up the embedded carbon fiber reinforced cement based material (CFRC), the carrying capacity and deformation of concrete member could be adjusted. The relationship between temperature difference and expansion strain of CFRC was demonstrated, and the temperature-deformation-load effect of concrete embedded with CFRC was studied. Heating the CFRC up to different temperatures resulted in different degree of inner pre-stress in concrete. Thus, the load capacity of concrete could be regulated owing to counteracting the pre-stress.

  20. Carrying capacity for the electromagnetic suspension low-speed maglev train on the horizontal curve

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Aiming at the lateral dislocation between the electromagnets and the rails on a horizontal curve,we investigated a single magnetic bogie of the maglev train in this paper.The magnetic levitation and guidance forces supplied by the suspension modules were deduced by the flux tube method.According to the dynamic equilibrium equations of the maglev train on the curved track with cant,several major factors that influence the carrying capacity were analyzed,and the formula of the carrying capacity was presented.The results provide a theoretical reference for the design of maglev train.

  1. Comprehensive Measurement for Carrying Capacity of Resources and Environment of City Clusters in Central China

    Institute of Scientific and Technical Information of China (English)

    FANG Chuanglin; LIU Xiaoli

    2010-01-01

    Studying the carrying capacity of resources and environment of city clusters in the central China has impor-tant practical guidance significance for promoting the healthy,sustainable and stable development of this region.Ac-cording to their influencing factors and reciprocity mechanism,using system dynamics approaches,this paper built a SD model for measuring the carrying capacity of resources and environment of the city clusters in the central China,and through setting different development models,the comprehensive measurement analysis on the carrying capacity was carried out.The results show that the model of promoting socio-economic development under the protection of resources and environment is the optimal model for promoting the harmony development of resources,environment,society and economy in the city clusters.According to this model,the optimum population scale of the city clusters in2020 is 42.80×106 persons,and the moderate economic development scale is 22.055× 1012 yuan(RMB).In 1996-2020,the carrying capacity of resources and environment in the city clusters took on obvious phase-change characteristics.During the studied period,it is basically at the initial development stage,and will come through the development process from slow development to speedup development.

  2. Factors affecting the environmental carrying capacity of a freshwater tropical lake system.

    Science.gov (United States)

    Mullakkezhil Reghunathan, Vishnuprasad; Joseph, Sabu; Warrier, C Unnikrishnan; Hameed, A Shahul; Albert Moses, Sheela

    2016-11-01

    Environmental carrying capacity is a measure of competence of a lake to accommodate pollution inputs without degrading water quality. In the research reported here, we identified the factors influencing the environmental carrying capacity of Vellayani Lake or VL (a typical tropical freshwater lake), Thiruvananthapuram, Kerala State, India. R-mode factor analysis is used to identify the factors controlling the carrying capacity of the lake, whereas hierarchical cluster analysis (HCA) helped to classify the lake. The carrying capacity of the lake is low with respect to alkalinity, due to ion deficiency, and is potentially reactive to sudden changes in pH. Eutrophic condition exists in the entire lake system. Acidic factor, mineralization factor, fertilizer factor (P & K), evaporation factor and organic pollution factor are the controllers of VL water quality during the pre-monsoon period. The same factors (but not evaporation factor) and an additional runoff factor control the water quality during monsoon. In the post-monsoon, the aforesaid factors (other than runoff, alkalinity) and soil erosion factor influence the water quality. Hence, managers of the lake system need to also focus on combating acidic factor during pre- and post-monsoons and runoff during monsoon. Smaller areal extent and shallow depth of VL, reduced outflow from it, less rainfall, presence of lateritic rock and soil and absence of limestone strata in the catchment are the chief elements affecting the acidic factor of Vellayani Lake.

  3. EFFICIENT, INTEGRATED TRANSPORT SYSTEM KEY TO PORT'S SUCCESS:Houston Sufficient support infrastructure, carrying capacity needed

    Institute of Scientific and Technical Information of China (English)

    ALAN DANIELS

    2005-01-01

    @@ An efficient, integrated transport system iskey to the Port of Vancouver s success. "There are many ways that we can optimizethe efficiency and carrying capacity of ourtransportation infrastructure in Canada: throughtechnology, by working together, by thinkingdifferently," said Captain Gordon Houston,President & CEO of the Vancouver Port Authority.

  4. Fuzzy Comprehensive Evaluation Model for Water Resources Carrying Capacity in Tarim River Basin, Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    MENG Lihong; CHEN Yaning; LI Weihong; ZHAO Ruifeng

    2009-01-01

    This paper explores the method of comprehensive evaluation of water resources carrying capacity and sets up an evaluation model applying the fuzzy comprehensive evaluation method. Based on the data of nature, society, economics and water resources of the Tarim River Basin in 2002, we evaluated the water resources carrying capacity of the basin by means of the model. The results show that the comprehensive grades are 0.438 and 0.454 for Aksu and Kashi prefectures respectively, where the current water resources exploitation and utilization has reached a relative high degree and there is only a very limited water carrying capacity, 0.620 for Kizilsu Kirgiz Autonomous Prefecture, where water resources carrying capacity is much higher, and in between for Hotan Prefecture and Bayingolin Mongolian Autonomous Prefecture. As a whole, the comprehensive grade of the Tarim River Basin is 0.508 and the current water resources exploitation and utilization has reached a relative high degree. Thus, we suggest that the integrated management of the water resources in the basin should be strengthened in order to utilize water resources scientifically and sustainably.

  5. Ecological Footprints and Appropriated Carrying Capacity: Measuring the Natural Capital Requirements of the Human Economy.

    Science.gov (United States)

    Ress, William E.; Wackernagel, Mathis

    1996-01-01

    Contrasts conventional economic rationality with economic principles. Develops an empirical approach based on a reinterpretation of carrying capacity that can account for technological advances and trade. Discusses the necessity of diverting much of the present consumption to investment in the maintenance of natural capital stocks. (AIM)

  6. Enhanced load-carrying capacity of hairy surfaces floating on water.

    Science.gov (United States)

    Xue, Yahui; Yuan, Huijing; Su, Weidong; Shi, Yipeng; Duan, Huiling

    2014-05-08

    Water repellency of hairy surfaces depends on the geometric arrangement of these hairs and enables different applications in both nature and engineering. We investigate the mechanism and optimization of a hairy surface floating on water to obtain its maximum load-carrying capacity by the free energy and force analyses. It is demonstrated that there is an optimum cylinder spacing, as a result of the compromise between the vertical capillary force and the gravity, so that the hairy surface has both high load-carrying capacity and mechanical stability. Our analysis makes it clear that the setae on water striders' legs or some insects' wings are in such an optimized geometry. Moreover, it is shown that surface hydrophobicity can further increase the capacity of a hairy surface with thick cylinders, while the influence is negligible when the cylinders are thin.

  7. Estimating a Global Hydrological Carrying Capacity Using GRACE Observed Water Stress

    Science.gov (United States)

    An, K.; Reager, J. T.; Famiglietti, J. S.

    2013-12-01

    Global population is expected to reach 9 billion people by the year 2050, causing increased demands for water and potential threats to human security. This study attempts to frame the overpopulation problem through a hydrological resources lens by hypothesizing that observed groundwater trends should be directly attributed to human water consumption. This study analyzes the relationships between available blue water, population, and cropland area on a global scale. Using satellite data from NASA's Gravity Recovery and Climate Experiment (GRACE) along with land surface model data from the Global Land Data Assimilation System (GLDAS), a global groundwater depletion trend is isolated, the validity of which has been verified in many regional studies. By using the inherent distributions of these relationships, we estimate the regional populations that have exceeded their local hydrological carrying capacity. Globally, these populations sum to ~3.5 billion people that are living in presently water-stressed or potentially water-scarce regions, and we estimate total cropland is exceeding a sustainable threshold by about 80 million km^2. Key study areas such as the North China Plain, northwest India, and Mexico City were qualitatively chosen for further analysis of regional water resources and policies, based on our distributions of water stress. These case studies are used to verify the groundwater level changes seen in the GRACE trend . Tfor the many populous, arid regions of the world that have already begun to experience the strains of high water demand.he many populous, arid regions of the world have already begun to experience the strains of high water demand. It will take a global cooperative effort of improving domestic and agricultural use efficiency, and summoning a political will to prioritize environmental issues to adapt to a thirstier planet. Global Groundwater Depletion Trend (Mar 2003-Dec 2011)

  8. Carrying capacities for nature parks as engines for sustainable regional development

    DEFF Research Database (Denmark)

    Brandt, Jesper; Holmes, Esbern

    of national and nature parks. Nature parks should rather develop towards a status as 'Biosphere Reserves' representing models for regional development, land use and landscape design in general. A relevant zoning of the regional environment of the Parks will be included as an instrument for such a strategy.......Growth in the number of visitors is an upcoming problem in nature parks. Nature parks are at the same time facing increasing demand, falling public appropriations and receding focus on their conservation functions. To ensure a balancing of nature protection and economic utilization the concept...... of carrying capacity has received increasing attention among park-authorities all over the world. A comparative analysis of conditions and initiatives related to visitor/nature carrying capacities in 8 nature parks in the Baltic region has been carried out. All the parks are candidates for recognition...

  9. Train Headway Models and Carrying Capacity of Super-Speed Maglev System

    Science.gov (United States)

    He, Shiwei; Song, Rui; Eastham, Tony

    Train headway models are established by analyzing the operation of the Transrapid Super-speed Maglev System (TSMS). The variation in the minimum allowable headway for trains of different speeds and consists is studied under various operational constraints. A potential Beijing-Shanghai Maglev line is used as an illustration to undertake capacity analyses with the model and methods. The example shows that the headway models for analyzing the carrying capacity of Maglev systems are very useful for the configurational design of this new transport system.

  10. Test-retest reliability of lifting and carrying in a 2-day functional capacity evaluation.

    Science.gov (United States)

    Reneman, M F; Dijkstra, P U; Westmaas, M; Göeken, L N H

    2002-12-01

    The objectives of this study were to establish test-retest reliability of lifting and carrying of a functional capacity evaluation (FCE) on two consecutive days and to verify the need for a 2-day protocol. A cohort of 50 patients (39 men, 11 women) with nonspecific low back pain were evaluated using a 2-day FCE protocol. Intraclass correlation coefficients (ICC) were calculated for weight lifted and carried. Predictive relationships between test and retest were explored by means of a regression analysis. The results of ICC were lifting low 0.87, lifting overhead 0.87, and carrying 0.77. Performances on day 2 were on an average 6-9% higher. Other than the amount of weight handled on day 1, no variable was found to predict performance on day 2. It was concluded that test-retest reliability of lifting and carrying was good, and the need for a 2-day protocol could not be confirmed.

  11. Assessing the Social Carrying Capacity of Diving Sites in Mabul Island, Malaysia

    Science.gov (United States)

    Zhang, Liye; Chung, ShanShan

    2015-12-01

    This study has explored social carrying capacity of an underwater environment based on divers' perceived crowding. Two dimensions were assessed, the number of divers seen and the proximity of diver. Data were obtained from a survey of 132 divers dived in Mabul Island, Malaysia during 2013-2014. Photographs depicting four levels of diver number and four levels of diver proximity in different combinations were shown to the respondents for assessing their acceptability. Between the two variables, the "number of divers" was the most influential factor for divers' perceived crowding. Divers would start to feel unacceptably crowded if 8-9 divers were visible to them at one time. Based on this, it is likely that the use level of diving sites in Mabul Island has already exceeded its social carrying capacity. Implications for future research and diving tourism management for Mabul Island are also discussed in the paper.

  12. Evaluation of Social Carrying Capacity of Topkapi Palace By Employees and Visitors

    Directory of Open Access Journals (Sweden)

    Kurban Ünlüönen

    2009-09-01

    Full Text Available Visitors’ using attraction resources at an optimum level is essential for the sustainable usage of areas. In fact Topkapı Palace arouses a considerable level of interest in terms of resources it has and this interest consequently leads to a concentration of visitors and a high degree of usage. The concentration in the area has utmost importance in terms of visitor carrying capacity. One of the groups who can evaluate the concentration present in this area most efficiently is the employees of the palace who are in continuous interaction with the visitors. One of the main objectives of this study is revealing the opinions of the employees on visitor carrying capacity. In order to gather information from the employees, face-to-face interview technique has been used and the evaluations of the employees have shown that visitor concentration has reached a level which may cause some negative results.

  13. Superior Current Carrying Capacity of Boron Nitride Encapsulated Carbon Nanotubes with Zero-Dimensional Contacts.

    Science.gov (United States)

    Huang, Jhao-Wun; Pan, Cheng; Tran, Son; Cheng, Bin; Watanabe, Kenji; Taniguchi, Takashi; Lau, Chun Ning; Bockrath, Marc

    2015-10-14

    We report fabrication and characterization of hexagonal boron nitride (hBN)-encapsulated carbon nanotube (CNT) field effect transistors, which are coupled to electrical leads via zero-dimensional contacts. Device quality is attested by the ohmic contacts and observation of Coulomb blockade with a single periodicity in small bandgap semiconducing nanotubes. Surprisingly, hBN-encapsulated CNT devices demonstrate significantly enhanced current carrying capacity; a single-walled CNT can sustain >180 μA current or, equivalently, a current density of ∼2 × 10(10) A/cm(2), which is a factor of 6-7 higher than devices supported on SiO2 substrates. Such dramatic enhancement of current carrying capacity arises from the high thermal conductivity of hBN and lower hBN-CNT interfacial thermal resistance and has implications for carbon electronic applications.

  14. Assessing the Social Carrying Capacity of Diving Sites in Mabul Island, Malaysia.

    Science.gov (United States)

    Zhang, Liye; Chung, ShanShan

    2015-12-01

    This study has explored social carrying capacity of an underwater environment based on divers' perceived crowding. Two dimensions were assessed, the number of divers seen and the proximity of diver. Data were obtained from a survey of 132 divers dived in Mabul Island, Malaysia during 2013-2014. Photographs depicting four levels of diver number and four levels of diver proximity in different combinations were shown to the respondents for assessing their acceptability. Between the two variables, the "number of divers" was the most influential factor for divers' perceived crowding. Divers would start to feel unacceptably crowded if 8-9 divers were visible to them at one time. Based on this, it is likely that the use level of diving sites in Mabul Island has already exceeded its social carrying capacity. Implications for future research and diving tourism management for Mabul Island are also discussed in the paper.

  15. Analysis on economic carrying capacity index of pig breeding in China

    Science.gov (United States)

    Leng, Bi-Bin; Liu, Jia-Ling; Xu, Yue-Feng

    2017-08-01

    In this paper, factor analysis method was employed to analyze and calculate the Gross Domestic Product (GDP) per capita in the last decade, the proportion of research and experiment development (R&D) expenditure equivalent to GDP, urban and rural residents’ pork consumption and explored the scale of Chinese pig breeding on economic carrying capacity index. The result showed that the growth of GDP had led to better techniques and higher field investment, and stronger support like science and technology from the government provided good conditions for large scale of pig breeding. Besides, the substantial increase of pork consumption between rural and urban residents has contributed to the pig breeding in large scale. As a result, the economic carrying capacity index in Chinese pig farming is on the rise.

  16. Integrating resource, social, and managerial indicators of quality into carrying capacity decision-making

    Science.gov (United States)

    Newman, P.; Marion, J.; Cahill, K.

    2001-01-01

    In park and wilderness management, integrating social and resource indicators is essential to meet park mandates that require the protection of both experiential and resource conditions. This paper will address the challenges we face in integrating social and resource data and outline a study in progress in Yosemite National Park. This study will develop and apply a management model that integrates resource, social and managerial indicators of quality into carrying capacity decisionmaking.

  17. Experimental Determination of Load Carrying Capacity of Point Contacts at Zero Entrainment Velocity

    Science.gov (United States)

    Shogrin, Bradley A.; Jones, William R., Jr.; Kingsbury, Edward P.; Prahl, Joseph M.

    1999-01-01

    A capacitance technique was used to monitor the film thickness separating two steel balls of a unique tribometer while subjecting the ball-ball contact to highly stressed, zero entrainment velocity (ZEV) conditions. All tests were performed under a N2 purge (R.H. carrying capacity at these zero entrainment velocity conditions, relevant to the ball-ball contact application in retainerless ball bearings.

  18. Thermal carrying capacity for a thermally-sensitive species at the warmest edge of its range.

    Directory of Open Access Journals (Sweden)

    Daniel Ayllón

    Full Text Available Anthropogenic environmental change is causing unprecedented rates of population extirpation and altering the setting of range limits for many species. Significant population declines may occur however before any reduction in range is observed. Determining and modelling the factors driving population size and trends is consequently critical to predict trajectories of change and future extinction risk. We tracked during 12 years 51 populations of a cold-water fish species (brown trout Salmo trutta living along a temperature gradient at the warmest thermal edge of its range. We developed a carrying capacity model in which maximum population size is limited by physical habitat conditions and regulated through territoriality. We first tested whether population numbers were driven by carrying capacity dynamics and then targeted on establishing (1 the temperature thresholds beyond which population numbers switch from being physical habitat- to temperature-limited; and (2 the rate at which carrying capacity declines with temperature within limiting thermal ranges. Carrying capacity along with emergent density-dependent responses explained up to 76% of spatio-temporal density variability of juveniles and adults but only 50% of young-of-the-year's. By contrast, young-of-the-year trout were highly sensitive to thermal conditions, their performance declining with temperature at a higher rate than older life stages, and disruptions being triggered at lower temperature thresholds. Results suggest that limiting temperature effects were progressively stronger with increasing anthropogenic disturbance. There was however a critical threshold, matching the incipient thermal limit for survival, beyond which realized density was always below potential numbers irrespective of disturbance intensity. We additionally found a lower threshold, matching the thermal limit for feeding, beyond which even unaltered populations declined. We predict that most of our study

  19. Thermal carrying capacity for a thermally-sensitive species at the warmest edge of its range.

    Science.gov (United States)

    Ayllón, Daniel; Nicola, Graciela G; Elvira, Benigno; Parra, Irene; Almodóvar, Ana

    2013-01-01

    Anthropogenic environmental change is causing unprecedented rates of population extirpation and altering the setting of range limits for many species. Significant population declines may occur however before any reduction in range is observed. Determining and modelling the factors driving population size and trends is consequently critical to predict trajectories of change and future extinction risk. We tracked during 12 years 51 populations of a cold-water fish species (brown trout Salmo trutta) living along a temperature gradient at the warmest thermal edge of its range. We developed a carrying capacity model in which maximum population size is limited by physical habitat conditions and regulated through territoriality. We first tested whether population numbers were driven by carrying capacity dynamics and then targeted on establishing (1) the temperature thresholds beyond which population numbers switch from being physical habitat- to temperature-limited; and (2) the rate at which carrying capacity declines with temperature within limiting thermal ranges. Carrying capacity along with emergent density-dependent responses explained up to 76% of spatio-temporal density variability of juveniles and adults but only 50% of young-of-the-year's. By contrast, young-of-the-year trout were highly sensitive to thermal conditions, their performance declining with temperature at a higher rate than older life stages, and disruptions being triggered at lower temperature thresholds. Results suggest that limiting temperature effects were progressively stronger with increasing anthropogenic disturbance. There was however a critical threshold, matching the incipient thermal limit for survival, beyond which realized density was always below potential numbers irrespective of disturbance intensity. We additionally found a lower threshold, matching the thermal limit for feeding, beyond which even unaltered populations declined. We predict that most of our study populations may become

  20. Ecological carrying capacity assessment of diving site: A case study of Mabul Island, Malaysia.

    Science.gov (United States)

    Zhang, Li-Ye; Chung, Shan-Shan; Qiu, Jian-Wen

    2016-12-01

    Despite considered a non-consumptive use of the marine environment, diving-related activities can cause damages to coral reefs. It is imminent to assess the maximum numbers of divers that can be accommodated by a diving site before it is subject to irreversible deterioration. This study aimed to assess the ecological carrying capacity of a diving site in Mabul Island, Malaysia. Photo-quadrat line transect method was used in the benthic survey. The ecological carrying capacity was assessed based on the relationship between the number of divers and the proportion of diver damaged hard corals in Mabul Island. The results indicated that the proportion of diver damaged hard corals occurred exponentially with increasing use. The ecological carrying capacity of Mabul Island is 15,600-16,800 divers per diving site per year at current levels of diver education and training with a quarterly threshold of 3900-4200 per site. Our calculation shows that management intervention (e.g. limiting diving) is justified at 8-14% of hard coral damage. In addition, the use of coral reef dominated diving sites should be managed according to their sensitivity to diver damage and the depth of the reefs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Approximate Solution of Oil Film Load-carrying Capacity of Turbulent Journal Bearing with Couple Stress Flow

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yongfang; WU Peng; GUO Bo; L Yanjun; LIU Fuxi; YU Yingtian

    2015-01-01

    The instability of the rotor dynamic system supported by oil journal bearing is encountered frequently, such as the half-speed whirl of the rotor, which is caused by oil film lubricant with nonlinearity. Currently, more attention is paid to the physical characteristics of oil film due to an oil-lubricated journal bearing being the important supporting component of the bearing-rotor systems and its nonlinear nature. In order to analyze the lubrication characteristics of journal bearings efficiently and save computational efforts, an approximate solution of nonlinear oil film forces of a finite length turbulent journal bearing with couple stress flow is proposed based on Sommerfeld and Ocvirk numbers. Reynolds equation in lubrication of a finite length turbulent journal bearing is solved based on multi-parametric principle. Load-carrying capacity of nonlinear oil film is obtained, and the results obtained by different methods are compared. The validation of the proposed method is verified, meanwhile, the relationships of load-carrying capacity versus eccentricity ratio and width-to-diameter ratio under turbulent and couple stress working conditions are analyzed. The numerical results show that both couple stress flow and eccentricity ratio have obvious influence on oil film pressure distribution, and the proposed method approximates the load-carrying capacity of turbulent journal bearings efficiently with various width-to-diameter ratios. This research proposes an approximate solution of oil film load-carrying capacity of turbulent journal bearings with different width-to-diameter ratios, which are suitable for high eccentricity ratios and heavy loads.

  2. Response of carrying capacity of piles induced by adjacent Metro tunneling

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-jie; DENG Fei-huang; WU Jia-jia; LIU Jian; WANG Fu-qiang

    2009-01-01

    Construction of tunnels in urban areas requires assessment of the impact of tunneling on the stability and integrity of existing pile foundations. We have focused our attention to the analysis of the carrying capacity of pile foundations provided by the impact of construction of urban tunnels on adjacent pile foundations, under the engineering background of the construction of the # 2 Line of the Guangzhou subway. It is carried out using a fast Lagrangian analysis of a continuum in a 3D numerical code, which is an elastoplastic three-dimensional finite difference model, to simulate the response of piles under the entire process of metro tun-neling (deactivation of soil element and activation of the lining). The adjacent stratum around the tunnel is classified into three re-gions: Zone Ⅰ(upper adjacent stratum of tunnel), Zone Ⅱ (45°-upper-lateral adjacent stratum of tunnel) and Zone Ⅲ (lateral adjacent stratum of tunnel). In each region one typical pile is chosen to be calculated and analyzed in detail. Numerical simulations are mainly conducted at three points of each pile shaft: the side-friction force of the pile, the tip resistance of the pile and the axial loading of the pile. A contrasting analysis has been conducted both in the response of typical piles in different regions and from computer calculated values with site monitoring values. The results of numerical simulations show that the impact on carrying ca-pacity of the piles lies mainly in the impact of construction of urban tunnels on the side-friction forces and the tip resistance of piles. The impact differs considerably among the different strata zones where the pile tips are located. The complicated rules of side-friction force and tip resistance of piles has resulted in complicated rules of pile axial loading thus, in the end, it impacts the carrying capacity of pile-foundations. It is necessary to take positive measures, such as stratum grouting stabilization or foundation underpinning, ete

  3. Capacity of Distribution Feeders for Hosting Distributed Energy Resources

    DEFF Research Database (Denmark)

    Papathanassiou, S.; Hatziargyriou, N.; Anagnostopoulos, P.

    The last two decades have seen an unprecedented development of distributed energy resources (DER) all over the world. Several countries have adopted a variety of support schemes (feed-in tariffs, green certificates, direct subsidies, tax exemptions etc.) so as to promote distributed generation (DG...... standards of the networks. To address this need in a timely and effective manner, simplified methodologies and practical rules of thumbs are often applied to assess the DER hosting capacity of existing distribution networks, avoiding thus detailed and time consuming analytical studies. The scope...

  4. Carrying capacity for shorebirds during migratory seasons at the Jiuduansha Wetland, Yangtze River Estuary, China

    Institute of Scientific and Technical Information of China (English)

    Zhenming GE; Xiao ZHOU; Wenyu SHI; Tianhou WANG

    2008-01-01

    The carrying capacity of food resources for migrating shorebirds was estimated at a stopover site in the Yangtze River Estuary during the two migratory sea-sons (spring and autumn). From March to May and September to November 2005, the macrobenthos resources of the Jiuduansha Wetland were investigated, and most of the macrobenthos species in the newly-formed shoal were found to be appropriate food for shorebirds. Biomass measurements showed that the total food resource was about 4541.20 kg AFDW (Ash-Free Dry Weight) in spring and about 2279.64 kg AFDW in autumn. Calculations were also done in the available habi-tats (intertidal bare mudflat and Scirpus x mariqueter/ Scirpus triqueter zones) for the shorebirds. The food resources in the available areas were about 3429.03 kg AFDW in spring and about 1700.92 kg AFDW in autumn. Based on the classification (by lean weight, basic metabolic rate and body length) of the shorebird community, and using the energy depletion model, it was theorized that all of the food resources in the Jiuduansha Wetland could support about 3.5 million shorebirds during spring season and 1.75 million shorebirds during autumn season. The shorebird carrying capacities in terms of the available food were about 2.6 million and 1.3 million birds during the two respective migration seasons. Considering the effect of intake rate, the potential carrying capacity was about 0.13-0.26 million shorebirds in the study area. The main factor restricting use of the area by shorebirds was the scarcity of available habitats for roosting at high tide rather than availability of food supply. We recommend restoring some wading pools in the dense Phragmites australis and Spartina alterniflora zones for shorebirds to roost in, to improve shorebirds' utilization efficiency of the resources in the Jiuduansha Wetland.

  5. Optimization of industrial structure based on water environmental carrying capacity in Tieling City.

    Science.gov (United States)

    Yue, Qiang; Hou, Limin; Wang, Tong; Wang, Liusuo; Zhu, Yue; Wang, Xiu; Cheng, Xilei

    2015-01-01

    A system dynamics optimization model of the industrial structure of Tieling City based on water environmental carrying capacity has been established. This system is divided into the following subsystems: water resources, economics, population, contaminants, and agriculture and husbandry. Three schemes were designed to simulate the model from 2011 to 2020, and these schemes were compared to obtain an optimal social and economic development model in Tieling City. Policy recommendations on industrial structure optimization based on the optimal solution provide scientific decision-making advice to develop a strong and sustainable economy in Tieling.

  6. Impact of Flexibility Options on Grid Economic Carrying Capacity of Solar and Wind: Three Case Studies

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Novacheck, Joshua [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Lab. (NREL), Golden, CO (United States); O' Connell, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-12-01

    In this study, we attempt to quantify the benefits of various options of grid flexibility by measuring their impact on two measures: economic carrying capacity and system costs. Flexibility can increase ECC and reduce overall system costs. In some cases, options that provide a limited increase in ECC can provide significant operational savings, thus demonstrating the need to evaluate flexibility options using multiple metrics. The value of flexibility options varies regionally due to different generation mixes and types of renewables. The more rapid decline in PV value compared to wind makes PV more dependent on adding flexibility options, including transmission and energy storage.

  7. The effect of manufacturing tolerances on the load carrying capacity of large diameter bearings

    Indian Academy of Sciences (India)

    Starvin M S; Manisekar K

    2015-09-01

    This paper deals with simplified 3D finite element (FE) analysis on the effect of manufacturing tolerances on the load carrying capacity of large diameter bearings based on Hertz theory. The nonlinear connector elements are used to model the rolling elements. This model enables us to evaluate the contact load on the rolling elements with relatively reduced calculation time. FE study has been carried out by allocating tolerance on balls and raceways using Monte Carlo simulation technique. The variation in dimension on balls is taken as per IS 2898-1976. A coding has been developed and employed for Monte Carlo simulation. Using the results of Monte Carlo simulation, tolerance has been assigned to the elements of large diameter bearing. From the results of finite element analysis, it is identified that analysis of large diameter bearing with tolerance on ball and raceway will lead to safe design.

  8. Studies on water resources carrying capacity in Tuhai river basin based on ecological footprint

    Science.gov (United States)

    Wang, Chengshuai; Xu, Lirong; Fu, Xin

    2017-05-01

    In this paper, the method of the water ecological footprint (WEF) was used to evaluate water resources carrying capacity and water resources sustainability of Tuhai River Basin in Shandong Province. The results show that: (1) The WEF had a downward trend in overall volatility in Tuhai River Basin from 2003 to 2011. Agricultural water occupies high proportion, which was a major contributor to the WEF, and about 86.9% of agricultural WEF was used for farmland irrigation; (2) The water resources carrying capacity had a downward trend in general, which was mostly affected by some natural factors in this basin such as hydrology and meteorology in Tuhai River Basin; (3) Based on analysis of water resources ecological deficit, it can be concluded that the water resources utilization mode was in an unhealthy pattern and it was necessary to improve the utilization efficiency of water resources in Tuhai River Basin; (4) In view of water resources utilization problems in the studied area, well irrigation should be greatly developed at the head of Yellow River Irrigation Area(YRIA), however, water from Yellow River should be utilized for irrigation as much as possible, combined with agricultural water-saving measures and controlled exploiting groundwater at the tail of YRIA. Therefore, the combined usage of surface water and ground water of YRIA is an important way to realize agricultural water saving and sustainable utilization of water resources in Tuhai River Basin.

  9. Disharmony between society and environmental carrying capacity: a historical review, with an emphasis on China.

    Science.gov (United States)

    Cao, Shixiong; Chen, Li; Liu, Zhande

    2007-07-01

    Nature can survive without humans, but humans cannot survive without nature. Despite a clear understanding of this dependency, humans continue to exist in disharmony with nature, and our current environmental and human dilemmas reflect old problems with a long history. Societies have historically experienced many transitions from harmony between nature and society to a crisis of disharmony, followed by a subsequent transition from crisis to harmony. Such ecological crises arise when society no longer practices sustainable consumption of resources within the limits imposed by the environmental carrying capacity. Over the long term, the growth in human desires has always exceeded the growth in the environmental carrying capacity. Science, technology, and social institutions must all be improved to resolve the ecological crises that arise from this imbalance. This paper discusses how increasing understanding of the problem by the public and by decision makers is the key to minimizing the undesirable impacts of the coming bottleneck for sustainable development. Furthermore, we emphasize how this awareness must be translated into fundamental political and economic changes.

  10. Study on the carry capacity of edible jellyfish fishery in Liaodong Bay

    Science.gov (United States)

    You, Kui; Bian, Yongning; Ma, Caihua; Chi, Xupeng; Liu, Zhiqiang; Zhang, Yuyu

    2016-06-01

    Jellyfish fishing is a special type of fishery that mainly exists in some countries of East and Southeast Asia. China has the largest jellyfish fishery yield in the world with an annual harvest of around 300 thousand tons. Liaodong Bay is the most important jellyfish fishery ground in China. However, due to the high benefits of jellyfish fishery, which leads to illegal and out-of-season jellyfish fishing occurring each year in Liaodong Bay. Illegal jellyfish fishery in Liaodong Bay is a typical example of the tragedy of the commons. The key problem is that fishermen seek to an illegally initiate jellyfish fishing as early as possible. In this paper, basing on the data of edible jellyfish's biology and ecology, we mainly analyzed the history of jellyfish fishery in China, especially in Liaodong bay, and then we calculated the carry capacity of edible jellyfish in Liaodong Bay which is about 300 thousand tons one year. This number is equal to the recent annual yield of edible jellyfish in China. Furthermore, basing on the carry capacity and reasonable quotas price analysis, we set up a Jellyfish fishing quotas and deficit quotas buyback system which could be a suitable and effective solution for jellyfish fishery management and development in Liaodong Bay at the underlying roots. Although China is the first country with edible jellyfish aquaculture, the annual yield of jellyfish aquaculture is only one fifth of jellyfish fishing. So, there is a very bright developing prospect about edible jellyfish aquaculture in China.

  11. Soil water carrying capacity of vegetation in the northeast of Ulan Buh Desert, China

    Institute of Scientific and Technical Information of China (English)

    Youliang TIAN; Yanhong HE; Liansheng GUO

    2009-01-01

    The dynamic change of soil water as a function of leaf area index and the soil water deficit value, prerequisites for assuring the survival of plants, were simulated. We established a dynamic soil water model based on a theory of water balance, the characteristics of the environment, and the physiological ecology of the plants in the Ulan Buh Desert, northwestern China. We estimated the soil water carrying capacity of the vegetation in our study area of the desert. The results showed that the proportion of soil evaporation in the total amount of precipitation was greater than 60% in the wandering and semifixed sands and 44.8% in the fixed sand. When the leaf area index was less than 1.7 m2/m2, the soil water deficit was maintained at a low level, but when the leaf area index continued to increase, the soil water deficit increased rapidly as well. In consequence, we come to the conclusion that the leaf area index of the soil water carrying capacity of the vegetation is 1.7 m2/m2 in our study area.

  12. A method for prediction of extent of microbial pollution of seawater and carrying capacity of beaches

    Science.gov (United States)

    Kocasoy, Günay

    1989-07-01

    The increase in the number of tourists visiting a coast is desired by most of the countries for economic reasons. However, this increase in tourism may cause pollution of the sea. This can be only avoided by proper planning and by predicting the “carrying capacity” of the coast in terms of sea pollution. This is especially important for developing countries where part of the wastewater is discharged without any treatment into the sea. In the present study the beaches were classified according to their use — and consequently the amount of waste discharged into the sea — into four groups: (1) coasts that are used only for swimming and recreational purposes; (2) coasts used simultaneously for dwelling, swimming, and recreational purposes; (3) coasts along which only dwellings exist; and (4) natural and man-made harbors, i.e., coasts used as shelters. During the survey,40,320 observations were made between December 1985 and February 1988 to determine the effect of the number of tourists on seawater quality. The results obtained were analyzed by a multilinear regression program to obtain an empirical equation giving the extent of the sea pollution in terms of coliform concentration as a function of population density and some other environmental factors. The equations derived in this study enable the determination of the carrying capacity of a beach in terms of pollution as well as the expected degree of pollution corresponding to a given population density. Furthermore, it allows the prediction of the extra carrying capacity that can be obtained by improving the waste-disposal conditions.

  13. Dynamic Response of RPC-Filled Steel Tubular Columns with High Load Carrying Capacity Under Axial Impact Loading

    Institute of Scientific and Technical Information of China (English)

    TIAN Zhimin; WU Ping'an; JIA Jianwei

    2008-01-01

    Experimental investigation into impact-resistant behavior of reactive powder concrete (RPC)-filled steel tubular columns was conducted, and dynamic response of the columns under axial impact loading was studied by means of numerical simulation method.Increase coefficient of load carrying capacity and ratio of load carrying capacity between steel tube and RPC core of columns were obtained.

  14. What is the carrying capacity for fish in the ocean? A meta analysis of population dynamics of North Atlantic cod

    DEFF Research Database (Denmark)

    Myers, R.A.; MacKenzie, Brian; Bowen, K.G.;

    2001-01-01

    model 21 Atlanic cod (Gadus morhua) stocks in the North Atlantic assuming that the maximum reproductive rate and the carrying capacity per unit area are random variables. This method uses a nonlinear mixed model and is a natural approach to investigate how carrying capacity varies among populations. We...... used empirical Bayes techniques to estimate the maximum reproductive rate and carrying capacity of each stock. In all cases, the empirical Bayes estimates were biologically reasonable, whereas a stock by stock analysis occasionally yielded nonsensical parameter estimates (e.g., infinite values). Our...... analysis showed that the carrying capacity per unit area varied by more than 20-fold among populations and that much of this variation was related to temperature. That is, the carrying capacity per square kilometre declines as temperature increases....

  15. Seasonal dynamics in wheel load-carrying capacity of a loam soil in the Swiss Plateau

    DEFF Research Database (Denmark)

    Gut, S.; Chervet, A.; Stettler, Matthias

    2015-01-01

    ) is defined as the maximum wheel load for a specific tyre and inflation pressure that does not result in soil stress in excess of soil strength. The soil strength and hence WLCC is strongly influenced by soil matric potential (h). The aim of this study was to estimate the seasonal dynamics in WLCC based...... on in situ measurements of h, measurements of precompression stress at various h and simulations of soil stress. In this work, we concentrated on prevention of subsoil compaction. Calculations were made for different tyres (standard and low-pressure top tyres) and for soil under different tillage...... and cropping systems (mouldboard ploughing, direct drilling, permanent grassland), and the computed WLCC was compared with real wheel loads to obtain the number of trafficable days (NTD) for various agricultural machines. Wheel load-carrying capacity was higher for the top than the standard tyres...

  16. NEW APPROACHES FOR COMPUTING DYNAMIC LOAD-CARRYING CAPACITY OF MULTIPLE COOPERATING ROBOTIC MANIPULATORS

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    A novel unified method for computing the dynamic load-carrying capacity(DLCC) of multiple cooperating robotic manipulators is developed.In this method,the kinematic constraints and the governing dynamic equations of the multiple robot system are formulated in the joint space by using the method of transference of dependence from one set of generalized coordinates to another,and the virtual work principle,which includes the readily available dynamics and joint torques of individual manipulators,and the dynamic of payload.Based on this dynamic model,the upper limit of the DLCC at any points on a given trajectory is obtained by solving a small-size linear programming problem.This method is conceptually straightforward,and it is applicable also to the cases of multi-fingered robot hands and multi-legged walking machines.

  17. Ecological Carrying Capacity of Tibet China--Variety of Ecological Footprints from 1978 to 2002

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-bao; GAO Ji-xi; Lori Anna Conzo; GAO Ming-gang; HE Ping

    2005-01-01

    Ecological footprint's theory and method are used to calculate and analysis the ecological carrying capacity in Tibet. The results indicate: Tibet ecological footprint (2.1 hm2) keeps higher than countrywide average level (1.5 hm2), and lower than global average level (2.4 hm2); the result show that Tibet pasture ecological footprint is the most different with other area, and woodland is the second; Tibet ecological footprint grows from 1.25 hm2 in 1978 to 2.09 hm2 in 2002, which states that life level is improving continuously; GDP (per RMB 104 Yuan) ecological footprint reduces from 61.9 hm2 in 1978 to 4.54 hm2 in 2002, which states resources utilized ratio is increasing continuously.

  18. Load carrying capacity of RCC beams by replacing steel reinforcement bars with shape memory alloy bars

    Science.gov (United States)

    Bajoria, Kamal M.; Kaduskar, Shreya S.

    2016-04-01

    In this paper the structural behavior of reinforced concrete (RC) beams with smart rebars under two point loading system has been numerically studied, using Finite Element Method. The material used in this study is Super-elastic Shape Memory Alloys (SE SMAs) which contains nickel and titanium. In this study, different quantities of steel and SMA rebars have been used for reinforcement and the behavior of these models under two point bending loading system is studied. A comparison of load carrying capacity for the model between steel reinforced concrete beam and the beam reinforced with S.M.A and steel are performed. The results show that RC beams reinforced with combination of shape memory alloy and steel show better performance.

  19. System dynamics model of Suzhou water resources carrying capacity and its application

    Directory of Open Access Journals (Sweden)

    Li CHENG

    2010-06-01

    Full Text Available A model of Suzhou water resources carrying capacity (WRCC was set up using the method of system dynamics (SD. In the model, three different water resources utilization programs were adopted: (1 continuity of existing water utilization, (2 water conservation/saving, and (3 water exploitation. The dynamic variation of the Suzhou WRCC was simulated with the supply-decided principle for the time period of 2001 to 2030, and the results were characterized based on socio-economic factors. The corresponding Suzhou WRCC values for several target years were calculated by the model. Based on these results, proper ways to improve the Suzhou WRCC are proposed. The model also produced an optimized plan, which can provide a scientific basis for the sustainable utilization of Suzhou water resources and for the coordinated development of the society, economy, and water resources.

  20. System dynamics model of Suzhou water resources carrying capacity and its application

    Institute of Scientific and Technical Information of China (English)

    Li CHENG

    2010-01-01

    A model of Suzhou water resources carrying capacity (WRCC) was set up using the method of system dynamics (SD).In the model, three different water resources utilization programs were adopted: (1) continuity of existing water utilization, (2) water conservation/saving, and (3) water exploitation.The dynamic variation of the Suzhou WRCC was simulated with the supply-decided principle for the time period of 2001 to 2030, and the results were characterized based on socio-economic factors.The corresponding Suzhou WRCC values for several target years were calculated by the model.Based on these results, proper ways to improve the Suzhou WRCC are proposed.The model also produced an optimized plan, which can provide a scientific basis for the sustainable utilization of Suzhou water resources and for the coordinated development of the society, economy, and water resources.

  1. Adhesive-bonded double-lap joints. [analytical solutions for static load carrying capacity

    Science.gov (United States)

    Hart-Smith, L. J.

    1973-01-01

    Explicit analytical solutions are derived for the static load carrying capacity of double-lap adhesive-bonded joints. The analyses extend the elastic solution Volkersen and cover adhesive plasticity, adherend stiffness imbalance and thermal mismatch between the adherends. Both elastic-plastic and bi-elastic adhesive representations lead to the explicit result that the influence of the adhesive on the maximum potential bond strength is defined uniquely by the strain energy in shear per unit area of bond. Failures induced by peel stresses at the ends of the joint are examined. This failure mode is particularly important for composite adherends. The explicit solutions are sufficiently simple to be used for design purposes

  2. Visitor perceptions and the shifting social carrying capacity of South Sinai's coral reefs.

    Science.gov (United States)

    Leujak, Wera; Ormond, Rupert F G

    2007-04-01

    To investigate how the perceptions and behaviour of visitors to coral reefs are influenced by their prior experience and knowledge of marine life, a questionnaire-based study was undertaken at sites in the Ras Mohammed National Park and at Sharm El Sheikh, South Sinai, Egypt. It was evident that over the 10-20 years during which these reefs have deteriorated (mainly due to reef-flat trampling), there have been interrelated shifts in the nature of visitors making use of them. First, there has been a shift from experienced divers and snorkellers to inexperienced snorkellers and non-snorkellers with a poorer knowledge of reef biology. Second, there has been a shift in the predominant nationalities of visitors, from German and British, through Italian, to Russian. More recent user groups both stated and showed that they had less experience of snorkelling; they also showed less knowledge of marine life and less interest in learning about it. Visitor perceptions of both the state of the marine life on the reefs and the acceptability of current visitor numbers also varied between groups. More recent visitor groups and visitors with less knowledge were more satisfied with reef health. In general, however, visitor perceptions of reef health did not correlate well with actual reef conditions, probably because more experienced visitors preferred less impacted sites with which they were nevertheless less satisfied than inexperienced visitors at heavily impacted sites. More recent visitor groups were also less bothered by crowding on the shore or in the water. Consequently, the apparent "social carrying capacity" of sites seems to be increasing to a level well above the likely "ecological carrying capacity".

  3. Relationships between nutritional condition of adult females and relative carrying capacity for rocky mountain Elk

    Science.gov (United States)

    Piasecke, J.R.; Bender, L.C.

    2009-01-01

    Lactation can have significant costs to individual and population-level productivity because of the high energetic demands it places on dams. Because the difference in condition between lactating and dry Rocky Mountain elk (Cervus elaphus nelsoni) cows tends to disappear as nutritional quality rises, the magnitude of that difference could be used to relate condition to habitat quality or the capability of habitats to support elk. We therefore compared nutritional condition of ???2.5-yr-old lactating and dry cows from six free-ranging RockyMountain elk populations throughout the United States.Our goal was to quantify differential accrual of body fat (BF) reserves to determine whether the condition of dry and lactating cows could be used to define relevant management thresholds of habitat quality (i.e., relative carrying capacity) and consequently potential performance of elk populations. Levels of BF that lactating cows were able to accrue in autumn and the proportional difference in BF between dry and lactating cows in autumn were related (F 1-2,10???16.2, Pnutritionally stressed condition, which may be limiting population performance. Using the logistic model to predict relative proximity to ecological carrying capacity (ECC), our population-years ranged from3-97%ofECCand proportion of the population lactating (an index of calf survival) was negatively related to proportion of ECC. Results indicate that the proportional difference in accrual of BF between lactating and dry cows can provide a sensitive index to where elk populations reside relative to the quality of their range.

  4. Effects of wetland management on carrying capacity of diving ducks and shorebirds in a coastal estuary

    Science.gov (United States)

    Brand, L. Arriana; Takekawa, John Y.; Shinn, Joel; Graham, Tanya; Buffington, Kevin; Gustafson, K. Benjamin; Smith, Lacy M.; Spring, Sarah E.; Miles, A. Keith

    2014-01-01

    With global loss of natural wetlands, managed wetlands increasingly support energy requirements for wintering shorebirds and waterfowl. Despite numerous studies of avian bioenergetics in freshwater systems, less is known of the energetic capacity of estuarine systems. In San Francisco Bay, managed saline ponds converted from former commercial salt evaporation ponds form part of the largest wetland restoration project on the Pacific coast of North America. A daily-ration model was applied to assess carrying capacity for diving ducks and shorebirds during four winter seasons (2007–2010) in seasonal and circulation ponds, each in two salinity classes. Diving ducks comprised an estimated 35,450 ± 1,559 (x ± SE) in average years and 45,458 ± 1,653 in peak years with > 95% in circulation ponds. Shorebirds comprised 64,253 ± 14,838 (x ± SE) in average years and 108,171 ± 4,854 in peak years with > 64% in seasonal ponds. Macroinvertebrate energy density was highest in mesohaline (5–30 ppt) circulation ponds and lowest in seasonal ponds for both guilds. Energy requirements for diving ducks in mesohaline followed by low-hyperhaline (30–80 ppt) circulation ponds were mostly met by available prey energy. Available energy for shorebirds was substantially less than they required in seasonal ponds but exceeded their needs in mesohaline circulation ponds. Mesohaline circulation ponds supported 9,443 ± 1,649 (x ± SE) shorebird use-days·ha-1 of accessible habitat and 2,297 ± 402 diving duck use-days·ha-1 of accessible habitat, twice the capacity of low-hyperhaline circulation ponds and greater than five times that of seasonal ponds for both guilds. Our results indicated that reducing salinity to mesohaline levels and altering water depth to increase accessibility substantially increased energy available for these species in estuarine managed ponds.

  5. STUDY OF CARRYING CAPACITY OF A CORRUGATED METAL CONSTRUCTION BY CRITERION OF YIELD HINGE DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Y. Y. Luchko

    2015-10-01

    Full Text Available Purpose. This research is aimed to: 1 calculation of equivalent forces caused by rolling stock in winter and summer seasons at different parameters of the irregularities of railway track; 2 research of bearing capacity of corrugated metal constructions (CMC in terms of development of plastic hinge in the top of the metal pipe due to irreversible residual deformation of the vertical and horizontal diameters of the pipe. Methodology. The calculation of equivalent forces is carried out according to the method of calculating the railway track on strength and stability. Further a mathematical algorithm was developed in the software environment of Mathcad 14, with which the calculations were made about the formation of a plastic hinge at the top of the pipe for different values of the irregularities of the railway track and the degree of compaction of soil backfill. In these studies, the calculations were carried out at the design value of the compaction degree of soil backfill and magnitude of dynamic loading on railway rolling stock. Findings. Analysis of multivariate calculations of testing the condition of occurrence of plastic hinge at the top of the pipe arch has revealed that the first plastic hinge, which occurs in the set of CMC is revealed only when there is a simultaneous unfavorable influence of two factors (causes. These are the factors: the assumption of the development of the track irregularities out of the allowable values without the implementation of measures to eliminate or limit the speed of trains (the first cause; reduction of compaction of soil backfill below the 90 % (the second cause. In case of absence of one of the causes the origin of the plastic hinge will not happen. Originality. It was the first time, when the bearing capacity of corrugated metal construction with large diameter (more than 6 m with account of factors complex: the degree of compaction of soil backfill, the magnitude of the dynamic loads from rolling stock

  6. A review and synthesis of recreation ecology research supporting carrying capacity and visitor use management decisionmaking

    Science.gov (United States)

    Marion, Jeff

    2016-01-01

    Resource and experiential impacts associated with visitation to wilderness and other similar backcountry settings have long been addressed by land managers under the context of “carrying capacity” decisionmaking. Determining a maximum level of allowable use, below which high-quality resource and experiential conditions would be sustained, was an early focus in the 1960s and 1970s. However, decades of recreation ecology research have shown that the severity and areal extent of visitor impact problems are influenced by an interrelated array of use-related, environmental, and managerial factors. This complexity, with similar findings from social science research, prompted scientists and managers to develop more comprehensive carrying capacity frameworks, including a new Visitor Use Management framework. These frameworks rely on a diverse array of management strategies and actions, often termed a “management toolbox,” for resolving visitor impact problems. This article reviews the most recent and relevant recreation ecology studies that have been applied in wildland settings to avoid or minimize resource impacts. The key findings and their management implications are highlighted to support the professional management of common trail, recreation site, and wildlife impact problems. These studies illustrate the need to select from a more diverse array of impact management strategies and actions based on an evaluation of problems to identify the most influential factors that can be manipulated.

  7. Evaluating the Carrying Capacity in The Škocjan Caves, Slovenia

    Science.gov (United States)

    Debevec Gerjevic, V.

    2009-04-01

    Park Škocjanske jame, Slovenija is a multidesignation site, located in south western part of Slovenia. In 1986 the Škocjanske jame - Škocjan Caves were listed in UNESCO world heritage list, in 1996 the Government of Republic Slovenia established the Regional Park Škocjanske jame, Slovenija. In 1999 the underground course of The Reka River in Škocjan Caves was designated a Ramsar site as first underground wetland of international importance. The park lies within three locations Natura 2000. In 2004 Park Škocjanske jame became a MAB locality as The Karst Biosphere Reserve. The tourist activity was already developed in the early 19th century. Today's research projects are focused on quality of caves microclimate, in order to enable the cave to remain as pristine as possible due to tourism and on the other hand to provide safe environment for people who work in the caves, and on quality of the water that flows from buffer zone to the underground world an then to the sea in Italy. The tourist activity increased during the past years. With the aim of nature conservation and protection the management plan was developed and special programme of monitoring started in order to detect changes in the environment due to the anthropogenic impact. In the park we consider the estimation of the carrying capacity as a key element for preparation of proper management guidelines for the tourism development in site. The caves system is rich in several halls and tunnels and distinguishes the caves for its variety of dimensions. There are several limitations of the visits and number of visitors. They merely depend on spatial characteristic of the caves and its surroundings and on human resources of the experts stuff that is in charge of guiding tourists groups to the caves. There is no simple formula that could be used for evaluation of capacity on general, but detailed studies of several locations and suitable description of parameters could give us an idea of proposing the

  8. Model for determining the load or carrying capacity of rivers and riverbanks for recreational use

    Directory of Open Access Journals (Sweden)

    Otero, I.

    2015-12-01

    Full Text Available The aim of this article is to determine the load or functional carrying capacity for the assimilation and recovery of rivers and riverbanks by compiling information on the environment, and to assess the potential for recreation from the environmental and scenic point of view. We set out to find the most significant basis for analysing the pressures limiting carrying capacity and constraining the demand for recreational use. This methodology will help planners and legislators in their decision-making. We also propose a methodology for assessing the recreational use of riverbanks, tested in a number of sites in the Madrid Region, in terms of the satisfaction the activity produces in the users, and the load or carrying capacity of the surrounding environment. A pilot site assessment is presented as a validation of the proposed methodology.El objetivo de este artículo es, determinar la capacidad de carga o acogida funcional, de asimilación y de recuperación de los márgenes y los cursos fluviales mediante la recopilación de información del medio; el potencial recreativo se evalúa además desde un doble punto de vista: ecológico y paisajístico. La forma en que se enfoca el problema y se presenta la metodología y los resultados puede resultar de gran utilidad para planificadores y legisladores. La metodología propuesta para valorar el uso recreativo de los márgenes fluviales, se aplica a una serie de parcelas en la Comunidad de Madrid, teniendo en cuenta la satisfacción que la actividad produce en los usuarios, y la capacidad de carga o acogida del entorno en el que se desarrollan. Como resultado, se presenta la valoración de parcelas piloto, que servirían para validar la metodología propuesta. [fr] Le but de cet article est, déterminer la capacité de charge ou réception fonctionnelle, l’assimilation et rétablissement des marges et les cours de la rivière par le biais de la collecte d’informations de l’environnement: le

  9. Habitat carrying capacity is reached for the European eel in a small coastal catchment: evidence and implications for managing eel stocks

    NARCIS (Netherlands)

    Acou, A.; Rivot, E.; van Gils, J.A.; Legault, A.; Ysnel, F.; Feunteun, E.

    2011-01-01

    1. Despite carrying capacity being one of the most important parameters in population management and modelling, we lack substantial evidence for habitat limitations on freshwater species. Here we tested the ideal free distribution (IFD) hypothesis using an indirect behaviour-based method for small c

  10. Climate Change Impacts to North Pacific Pelagic Habitat Are Projected to Lower Carrying Capacity

    Science.gov (United States)

    Woodworth-Jefcoats, P. A.; Polovina, J. J.; Drazen, J.

    2016-02-01

    We use output from a suite of CMIP5 earth system models to explore the impacts of climate change on marine fisheries over the 21st century. Ocean temperatures from both the historical and RCP 8.5 projections are integrated over the upper 200 m of the water column to characterize thermal habitat in the epipelagic realm. We find that across all models the projected temperature increases lead to a redistribution of thermal habitat: temperatures that currently represent the majority of North Pacific pelagic habitat are replaced by temperatures several degrees warmer. Additionally, all models project the emergence of new thermal habitat that exceeds present-day maximum temperatures. Spatially, present-day thermal habitat retreats northward and contracts eastward as warmer habitat in the southern and western North Pacific expands. In addition to these changes in thermal habitat, zooplankton densities are projected to decline across much of the North Pacific. Taken together, warming temperatures and declining zooplankton densities create the potential for mismatches in metabolic demand and supply through the 21st century. We find that carrying capacity for tropical tunas and other commercially valuable pelagic fish may be especially vulnerable to the impacts of climate change. The waters projected to see the greatest redistribution of thermal habitat and greatest declines in zooplankton densities are primarily those targeted by the Hawaii-based and international longline fleets. Fishery managers around the North Pacific will need to incorporate these impacts of climate change into future management strategies.

  11. Multiple Carrying Capacities from a management-oriented perspective to operationalize sustainable tourism in protected areas.

    Science.gov (United States)

    Salerno, Franco; Viviano, Gaetano; Manfredi, Emanuela C; Caroli, Paolo; Thakuri, Sudeep; Tartari, Gianni

    2013-10-15

    This article describes how the concept of Tourism Carrying Capacity (TCC) has shifted from a uni-dimensional approach to incorporating environmental, social and political aspects. This shift is demonstrated by a study of a large, internationally popular protected area used by trekkers, the Mt. Everest Region, where qualitative data collected from visitors was combined with environmental modeling using a participatory framework. Tourist satisfaction showed positive margins for further tourist industry expansion, but current environmental conditions limit growth and further development. Space and time dimensions were also considered. We observed that the limits on growth and further development can be manipulated, with a certain degree of flexibility, through investments and regulatory measures. We hypothesized that TCC can play an important role in the management of protected areas only if it is viewed as a systematic, strategic policy tool within a planning process rather than as a unique, intrinsic number that is not modifiable. We conclude that to translate the strategy into action using standard measures, further investigation is needed to balance the various TCC components as a part of a decision-making framework that includes the integration of different cultural approaches and policy needs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Temperature dependences of growth rates and carrying capacities of marine bacteria depart from metabolic theoretical predictions

    KAUST Repository

    Huete-Stauffer, Tamara Megan

    2015-09-11

    Using the metabolic theory of ecology (MTE) framework, we evaluated over a whole annual cycle the monthly responses to temperature of the growth rates (μ) and carrying capacities (K) of heterotrophic bacterioplankton at a temperate coastal site. We used experimental incubations spanning 6oC with bacterial physiological groups identified by flow cytometry according to membrane integrity (live), nucleic acid content (HNA and LNA) and respiratory activity (CTC+). The temperature dependence of μat the exponential phase of growth was summarized by the activation energy (E), which was variable (-0.52 to 0.72 eV) but followed a seasonal pattern, only reaching the hypothesized value for aerobic heterotrophs of 0.65 eV during the spring bloom for the most active bacterial groups (live, HNA, CTC+). K (i.e. maximum experimental abundance) peaked at 4 × 106 cells mL-1 and generally covaried with μbut, contrary to MTE predictions, it did not decrease consistently with temperature. In the case of live cells, the responses of μand K to temperature were positively correlated and related to seasonal changes in substrate availability, indicating that the responses of bacteria to warming are far from homogeneous and poorly explained by MTE at our site. © FEMS 2015.

  13. Assessing the air pollution carrying capacity of the northern Puget Sound region: an application of TAPAS

    Energy Technology Data Exchange (ETDEWEB)

    Wood, M.C.; Childs J.E.; Marlatt, W.E.

    1980-09-01

    The technique discussed, the Topographic Air Pollution Analysis System (TAPAS), was developed to provide valid information on the dispersion capability of the lower atmosphere in areas characterized by complex terrain features. A study was undertaken to assess the air quality (SO/sub 2/) impacts associated with energy development in the region and to determine the constraints on energy development due to regulated limitations on the amount of air quality degradation allowable in the area. The emission constraint analysis for the northern Puget Sound region indicated that total SO/sub 2/ emissions in the core area (on an annual basis) are less than half of the amount that could be tolerated in the entire core region while maintaining ambient concentrations within state and federal annual average limitations. However, comparison of source characteristics with source location and grid cell emission restrictions indicated that localized areas adjacent to the major point sources are already far in excess of the SO/sub 2/ carrying capacity. This conclusion is supported by air quality monitoring data that indicate state standard violations at several receptor locations within the study area. The annual maps of wind patterns and PI-Matrix values show areas of both good and poor dispersion characteristics under the most prevalent flow conditions.

  14. Cultural carrying capacity: Organ donation advocacy, discursive framing, and social media engagement.

    Science.gov (United States)

    Bail, Christopher A

    2016-09-01

    Social media sites such as Facebook have become a powerful tool for public health outreach because they enable advocacy organizations to influence the rapidly increasing number of people who frequent these forums. Yet the very open-ness of social media sites creates fierce competition for public attention. The vast majority of social media messages provoke little or no reaction because of the sheer volume of information that confronts the typical social media user each day. In this article, I present a theory of the "cultural carrying capacity" of social media messaging campaigns. I argue that advocacy organizations inspire more endorsements, comments, and shares by social media users if they diversify the discursive content of their messages. Yet too much diversification creates large, disconnected audiences that lack the sense of shared purpose necessary to sustain an online movement. To evaluate this theory, I created a Facebook application that collects social media posts produced by forty-two organ donation advocacy organizations over 1.5 years, as well as supplemental information about the organization, its audience, and the broader social context in which they interact. Time series models provide strong evidence for my theory net of demographic characteristics of social media users, the resources and tactics of each organization, and broader external factors. I conclude by discussing the implications of these findings for public health, cultural sociology, and the nascent field of computational social science. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Benchmarking the Enrolment Structure of an Educational System without Exceeding the Carrying Capacity Requirement

    Directory of Open Access Journals (Sweden)

    Virtue Uwabomwen EKHOSUEHI

    2013-12-01

    Full Text Available In this paper, we propose an enrolment projection method based on the carrying capacity of the educational system. The method is a refinement of the recruitment control strategy proposed in the literature. We implement our proposed method using enrolment data from a university setting. The results obtained by extrapolating the short-term shifts in enrolment structure reflect the normal progression pattern in the system. Normal 0 false false false EN-US X-NONE AR-SA /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";}

  16. Experimental Study of Load Carrying Capacity of Point Contacts at Zero Entrainment Velocity

    Science.gov (United States)

    Shogin, B. A.; Jones, W. R., Jr.; Kingsbury, E. P.; Jansen, M. J.; Prahl, J. M.

    1998-01-01

    A capacitance technique was used to monitor the film thickness separating two steel balls while subjecting the ball-ball contact to highly stressed, zero entrainment velocity conditions. Tests were performed in a nitrogen atmosphere and utilized 52100 steel balls and a polyalphaolefin lubricant. Capacitance to film thickness accuracy was verified under pure rolling conditions using established EHL theory. Zero entrainment velocity tests were performed at sliding speeds from 6.0 to 10.0 m/s and for sustained amounts of time to 28.8 min. The protective lubricant film separating the specimens at zero entrainment velocity had a film thickness between 0.10 to 0.14 microns (4 to 6 micro in.), which corresponded to a k value of 4. The formation of an immobile surface film formed by lubricant entrapment is discussed as an explanation of the load carrying capacity at zero entrainment velocity conditions, relevant to the ball-ball contacts occurring in retainerless ball bearings.

  17. (ANTI)PETER Principle - Discrete (INVERSE) Logistic Equation with Imprecisely Estimated and Stimulated Carrying Capacity

    CERN Document Server

    Pankovic, V; Glavatovic, R

    2009-01-01

    In this work we consider the Peter principle and anti-Peter principle as the discrete logistic and discrete inverse logistic equation. Especially we discuss imprecisely estimated (by hierarchical control mechanism) carrying capacity, i.e. boundary (in)competence level of a hierarchy member. It implies that Peter principle holds two sub-principles. In the first one objective boundary competence level is increased for estimation error. In the second one objective boundary competence level is decreased for estimation error. Similarly, anti-Peter principle holds two sub-principles too. All this implies that paradoxical situations that follow from Peter and anti-Peter principle can be simply removed by decrease of the error of hierarchical (social) control. Also we discuss cases by Peter principle when error of the boundary competence level by estimation grows up. (Then, in fact, there is no estimation error but stimulation of the boundary level by control mechanism.) By first Peter sub-principle it implies anarch...

  18. Screening for EIA in India: enhancing effectiveness through ecological carrying capacity approach.

    Science.gov (United States)

    Rajaram, T; Das, Ashutosh

    2011-01-01

    Developing countries across the world have embraced the policy of high economic growth as a means to reduce poverty. This economic growth largely based on industrial output is fast degrading the ecosystems, jeopardizing their long term sustainability. Environmental Impact Assessment (EIA) has long been recognized as a tool which can help in protecting the ecosystems and aid sustainable development. The Screening guidelines for EIA reflect the level of commitment the nation displays towards tightening its environmental protection system. The paper analyses the screening process for EIA in India and dissects the rationale behind the exclusions and thresholds set in the screening process. The screening process in India is compared with that of the European Union with the aim of understanding the extent of deviations from a screening approach in the context of better economic development. It is found that the Indian system excludes many activities from the purview of screening itself when compared to the EU. The constraints responsible for these exclusions are discussed and the shortcomings of the current command and control system of environmental management in India are also explained. It is suggested that an ecosystem carrying capacity based management system can provide significant inputs to enhance the effectiveness of EIA process from screening to monitoring.

  19. 土地综合承载力研究现状%Overview of the Land Comprehensive Carrying Capacity

    Institute of Scientific and Technical Information of China (English)

    刘梦

    2014-01-01

    The land comprehensive carrying capacity refers to the economic carrying capacity, social carrying capacity and ecological carrying capacity of a region��s land. Based on a review of the land comprehensive carrying capacity re⁃search, its characteristics such as the monotone research method, the incomprehensive content despite the hierarchical re⁃gional research as well as the singleness of research object were summerized, pointing out that the method of constructing the index system is the major method to evaluate carrying capacity of the land. The method of improving the land compre⁃hensive carrying capacity and the prospection of the land comprehensive carrying capacity were discussed, and the con⁃clusion that the new trend is to combine the“qualitative”with“quantitative”and to broaden the range of research was given.%土地综合承载力是一个区域土地经济承载力、社会承载力以及生态承载力的综合能力的反映。在回顾土地综合承载力研究的基础上,总结其研究方法不够多样化、研究区域具有层次性但研究内容不够全面、研究对象较单一等特点,指出通过构建指标体系的方法是评价土地综合承载力的主流方法,并提出了提高土地综合承载力的方法,对土地综合承载力研究进行了展望,认为“定性”与“定量”结合、拓宽研究范围等将成为研究新趋势。

  20. [Measuring water ecological carrying capacity with the ecosystem-service-based ecological footprint (ESEF) method: Theory, models and application].

    Science.gov (United States)

    Jiao, Wen-jun; Min, Qing-wen; Li, Wen-hua; Fuller, Anthony M

    2015-04-01

    Integrated watershed management based on aquatic ecosystems has been increasingly acknowledged. Such a change in the philosophy of water environment management requires recognizing the carrying capacity of aquatic ecosystems for human society from a more general perspective. The concept of the water ecological carrying capacity is therefore put forward, which considers both water resources and water environment, connects socio-economic development to aquatic ecosystems and provides strong support for integrated watershed management. In this paper, the authors proposed an ESEF-based measure of water ecological carrying capacity and constructed ESEF-based models of water ecological footprint and capacity, aiming to evaluate water ecological carrying capacity with footprint methods. A regional model of Taihu Lake Basin was constructed and applied to evaluate the water ecological carrying capacity in Changzhou City which located in the upper reaches of the basin. Results showed that human demand for water ecosystem services in this city had exceeded the supply capacity of local aquatic ecosystems and the significant gap between demand and supply had jeopardized the sustainability of local aquatic ecosystems. Considering aqua-product provision, water supply and pollutant absorption in an integrated way, the scale of population and economy aquatic ecosystems in Changzhou could bear only 54% of the current status.

  1. Proactive monitoring and adaptive management of social carrying capacity in Arches National Park: an application of computer simulation modeling.

    Science.gov (United States)

    Lawson, Steven R; Manning, Robert E; Valliere, William A; Wang, Benjamin

    2003-07-01

    Public visits to parks and protected areas continue to increase and may threaten the integrity of natural and cultural resources and the quality of the visitor experience. Scientists and managers have adopted the concept of carrying capacity to address the impacts of visitor use. In the context of outdoor recreation, the social component of carrying capacity refers to the level of visitor use that can be accommodated in parks and protected areas without diminishing the quality of the visitor experience to an unacceptable degree. This study expands and illustrates the use of computer simulation modeling as a tool for proactive monitoring and adaptive management of social carrying capacity at Arches National Park. A travel simulation model of daily visitor use throughout the Park's road and trail network and at selected attraction sites was developed, and simulations were conducted to estimate a daily social carrying capacity for Delicate Arch, an attraction site in Arches National Park, and for the Park as a whole. Further, a series of simulations were conducted to estimate the effect of a mandatory shuttle bus system on daily social carrying capacity of Delicate Arch to illustrate how computer simulation modeling can be used as a tool to facilitate adaptive management of social carrying capacity.

  2. GIS and agent based spatial-temporal simulation modeling for assessing tourism social carrying capacity: a study on Mount Emei scenic area, China

    Science.gov (United States)

    Zhang, Renjun

    2007-06-01

    Each scenic area can sustain a specific level of acceptance of tourist development and use, beyond which further development can result in socio-cultural deterioration or a decline in the quality of the experience gained by visitors. This specific level is called carrying capacity. Social carrying capacity can be defined as the maximum level of use (in terms of numbers and activities) that can be absorbed by an area without an unacceptable decline in the quality of experience of visitors and without an unacceptable adverse impact on the society of the area. It is difficult to assess the carrying capacity, because the carrying capacity is determined by not only the number of visitors, but also the time, the type of the recreation, the characters of each individual and the physical environment. The objective of this study is to build a spatial-temporal simulation model to simulate the spatial-temporal distribution of tourists. This model is a tourist spatial behaviors simulator (TSBS). Based on TSBS, the changes of each visitor's travel patterns such as location, cost, and other states data are recoded in a state table. By analyzing this table, the intensity of the tourist use in any area can be calculated; the changes of the quality of tourism experience can be quantized and analyzed. So based on this micro simulation method the social carrying capacity can be assessed more accurately, can be monitored proactively and managed adaptively. In this paper, the carrying capacity of Mount Emei scenic area is analyzed as followed: The author selected the intensity of the crowd as the monitoring Indicators. it is regarded that longer waiting time means more crowded. TSBS was used to simulate the spatial-temporal distribution of tourists. the average of waiting time all the visitors is calculated. And then the author assessed the social carrying capacity of Mount Emei scenic area, found the key factors have impacted on social carrying capacity. The results show that the TSBS

  3. 青海省玉树州相对资源承载力评价%Evaluation of Relative Carrying Capacity of Resources in Yushu,Qinghai Province

    Institute of Scientific and Technical Information of China (English)

    李明明

    2013-01-01

    By using the improved model of relative carrying capacity of resources,this paper evaluates the spatial-temporal carrying capacity of resources in Yushu area The result shows that the relative carrying capacity of resources was in a surplus state from 1999 to 2008,but the surplus was decreasing.The carrying capacity of land resources is much higher than that of economic resources,and the resources of grassland and woodland have made the greatest contribution to the carrying capacity of synthetic resources.In addition,the carrying capacity of resources in Yushu area is characterized by an obvious spatial distribution,with differences of the carrying capacity between the west-eastern areas and the north-southern areas.%采用修正后的相对资源承载力模型从时间和空间对玉树州资源承载力进行评价,结果表明:1999-2008年间,玉树州相对资源承载力处于富余状态,但富余量在逐渐减小;土地资源承载力远大于经济资源承载力,其中牧草地资源和林地资源对综合资源承载力贡献最大;资源承载力空间分布特征明显,主要表现为东西部和南北部的资源承载力分布差异.

  4. Estimating habitat carrying capacity for migrating and wintering waterfowl: Considerations, pitfalls and improvements

    Science.gov (United States)

    Williams, Christopher; Dugger, Bruce D.; Brasher, Michael G.; Coluccy, John M.; Cramer, Dane M.; Eadie, John M.; Gray, Matthew J.; Hagy, Heath M.; Livolsi, Mark; McWilliams, Scott R.; Petrie, Matthew; Soulliere, Gregory J.; Tirpak, John M.; Webb, Elisabeth B.

    2014-01-01

    Population-based habitat conservation planning for migrating and wintering waterfowl in North America is carried out by habitat Joint Venture (JV) initiatives and is based on the premise that food can limit demography (i.e. food limitation hypothesis). Consequently, planners use bioenergetic models to estimate food (energy) availability and population-level energy demands at appropriate spatial and temporal scales, and translate these values into regional habitat objectives. While simple in principle, there are both empirical and theoretical challenges associated with calculating energy supply and demand including: 1) estimating food availability, 2) estimating the energy content of specific foods, 3) extrapolating site-specific estimates of food availability to landscapes for focal species, 4) applicability of estimates from a single species to other species, 5) estimating resting metabolic rate, 6) estimating cost of daily behaviours, and 7) estimating costs of thermoregulation or tissue synthesis. Most models being used are daily ration models (DRMs) whose set of simplifying assumptions are well established and whose use is widely accepted and feasible given the empirical data available to populate such models. However, DRMs do not link habitat objectives to metrics of ultimate ecological importance such as individual body condition or survival, and largely only consider food-producing habitats. Agent-based models (ABMs) provide a possible alternative for creating more biologically realistic models under some conditions; however, ABMs require different types of empirical inputs, many of which have yet to be estimated for key North American waterfowl. Decisions about how JVs can best proceed with habitat conservation would benefit from the use of sensitivity analyses that could identify the empirical and theoretical uncertainties that have the greatest influence on efforts to estimate habitat carrying capacity. Development of ABMs at

  5. Biofilm growth mode promotes maximum carrying capacity and community stability during product inhibition syntrophy.

    Science.gov (United States)

    Brileya, Kristen A; Camilleri, Laura B; Zane, Grant M; Wall, Judy D; Fields, Matthew W

    2014-01-01

    Sulfate-reducing bacteria (SRB) can interact syntrophically with other community members in the absence of sulfate, and interactions with hydrogen-consuming methanogens are beneficial when these archaea consume potentially inhibitory H2 produced by the SRB. A dual continuous culture approach was used to characterize population structure within a syntrophic biofilm formed by the SRB Desulfovibrio vulgaris Hildenborough and the methanogenic archaeum Methanococcus maripaludis. Under the tested conditions, monocultures of D. vulgaris formed thin, stable biofilms, but monoculture M. maripaludis did not. Microscopy of intact syntrophic biofilm confirmed that D. vulgaris formed a scaffold for the biofilm, while intermediate and steady-state images revealed that M. maripaludis joined the biofilm later, likely in response to H2 produced by the SRB. Close interactions in structured biofilm allowed efficient transfer of H2 to M. maripaludis, and H2 was only detected in cocultures with a mutant SRB that was deficient in biofilm formation (ΔpilA). M. maripaludis produced more carbohydrate (uronic acid, hexose, and pentose) as a monoculture compared to total coculture biofilm, and this suggested an altered carbon flux during syntrophy. The syntrophic biofilm was structured into ridges (∼300 × 50 μm) and models predicted lactate limitation at ∼50 μm biofilm depth. The biofilm had structure that likely facilitated mass transfer of H2 and lactate, yet maximized biomass with a more even population composition (number of each organism) when compared to the bulk-phase community. Total biomass protein was equivalent in lactate-limited and lactate-excess conditions when a biofilm was present, but in the absence of biofilm, total biomass protein was significantly reduced. The results suggest that multispecies biofilms create an environment conducive to resource sharing, resulting in increased biomass retention, or carrying capacity, for cooperative populations.

  6. Density and carrying capacity in the forgotten tigerland: tigers in understudied Nepalese Churia.

    Science.gov (United States)

    Thapa, Kanchan; Kelly, Marcella J

    2016-10-13

    While there are numerous wildlife ecology studies in lowland areas of Nepal, there are no in-depth studies of the hilly Churia habitat even though it comprises 7,642 km(2) of potential wildlife habitat across the Terai Arc. We investigated tiger, leopard, and prey densities across this understudied habitat. Our camera trapping survey covered 536 km(2) of Churia and surrounding areas within Chitwan National Park (CNP). We used 161 trapping locations and accumulated 2,097 trap nights in a 60-day survey period during the winter season of 2010-2011. Additionally, we walked 136 km over 81 different line transects using distance sampling to estimate prey density. We photographed 31 individual tigers, 28 individual leopards, and 25 other mammalian species. Spatial capture recapture methods resulted in lower density estimates for tigers ranging from 2.3-2.9 tigers per 100 km(2) , than for leopards, which ranged from 3.3-5.1 leopards per 100 km(2) . Additionally, leopard densities were higher in the core of the Churia compared to surrounding areas. We estimated 62.7 prey animals per 100 km(2) with forest ungulate prey (sambar, chital, barking deer, and wild pig) accounting for 47% of the total. Based on prey availability, Churia habitat within CNP could potentially support 5.86 tigers per 100 km(2) but our density estimates were lower, perhaps indicating the tiger population is below carrying capacity. Our results demonstrate that Churia habitat should not be ignored in conservation initiatives, but rather management efforts should focus on reducing human disturbance to support higher predator numbers. This article is protected by copyright. All rights reserved.

  7. Decline in territory size and fecundity as a response to carrying capacity in an endangered songbird.

    Science.gov (United States)

    Hartmann, Stefanie A; Oppel, Steffen; Segelbacher, Gernot; Juiña, Mery E; Schaefer, H Martin

    2017-02-01

    Density-dependent processes are fundamental mechanisms for the regulation of populations. Ecological theories differ in their predictions on whether increasing population density leads to individual adjustments of survival and reproductive output or to dominance and monopolization of resources. Here, we use a natural experiment to examine which factors limit population growth in the only remaining population of the endangered pale-headed brush finch (Atlapetes pallidiceps). For three distinct phases (a phase of population suppression, 2001-2002; expansion due to conservation management, 2003-2008; and equilibrium phase, 2009-2014), we estimated demographic parameters with an integrated population model using population size, the proportion of successfully breeding pairs and their productivity, territory size, and mark-recapture data of adult birds. A low proportion of successful breeders due to brood parasitism (0.42, 95% credible interval 0.26-0.59) limited population growth before 2003; subsequent culling of the brood parasite resulted in a two-fold increase of the proportion of successful breeders during the 'expansion phase'. When the population approached the carrying capacity of its habitat, territory size declined by more than 50% and fecundity declined from 1.9 (1.54-2.27) to 1.3 (1.12-1.53) chicks per breeding pair, but the proportion of successful breeders remained constant (expansion phase: 0.85; 0.76-0.93; equilibrium phase: 0.86; 0.79-0.92). This study demonstrates that limiting resources can lead to individual adjustments instead of despotic behavior, and the individual reduction of reproductive output at high population densities is consistent with the slow life-history of many tropical species.

  8. The tourism carrying capacity of underwater trails in Isabel Island National Park, Mexico.

    Science.gov (United States)

    Ríos-Jara, Eduardo; Galván-Villa, Cristian Moisés; Rodríguez-Zaragoza, Fabián Alejandro; López-Uriarte, Ernesto; Muñoz-Fernández, Vicente Teófilo

    2013-08-01

    The popularity of ecotourism in the marine protected areas of Mexico has increased over the last 10 years; in particular there is a large development of a SCUBA diving industry in the Mexican Pacific including Isabel Island. Given the risks associated with human activity in the marine environments around this island, we propose two ecotourism management strategies: (1) the creation and use of underwater trails, and (2) the estimation of the specific tourism carrying capacity (TCC) for each trail. Six underwater trails were selected in sites that presented elements of biological, geological, and scenic interest, using information obtained during field observations. The methodology used to estimate the TCC was based upon the physical and biological conditions of each site, the infrastructure and equipment available, and the characteristics of the service providers and the administrators of the park. Correction factors of the TCC included elements of the quality of the visit and the threat and vulnerability of the marine environment of each trail (e.g., divers' expertise, size and distance between groups of divers, accessibility, wind, coral coverage). The TCC values ranged between 1,252 and 1,642 dives/year/trail, with a total of 8,597 dives/year for all six trails. Although these numbers are higher than the actual number of recreational visitors to the island (~1,000 dives per year), there is a need for adequate preventive management if the diving sites are to maintain their esthetic appeal and biological characteristics. Such management might be initially directed toward using only the sites and the TCC proposed here.

  9. The Tourism Carrying Capacity of Underwater Trails in Isabel Island National Park, Mexico

    Science.gov (United States)

    Ríos-Jara, Eduardo; Galván-Villa, Cristian Moisés; Rodríguez-Zaragoza, Fabián Alejandro; López-Uriarte, Ernesto; Muñoz-Fernández, Vicente Teófilo

    2013-08-01

    The popularity of ecotourism in the marine protected areas of Mexico has increased over the last 10 years; in particular there is a large development of a SCUBA diving industry in the Mexican Pacific including Isabel Island. Given the risks associated with human activity in the marine environments around this island, we propose two ecotourism management strategies: (1) the creation and use of underwater trails, and (2) the estimation of the specific tourism carrying capacity (TCC) for each trail. Six underwater trails were selected in sites that presented elements of biological, geological, and scenic interest, using information obtained during field observations. The methodology used to estimate the TCC was based upon the physical and biological conditions of each site, the infrastructure and equipment available, and the characteristics of the service providers and the administrators of the park. Correction factors of the TCC included elements of the quality of the visit and the threat and vulnerability of the marine environment of each trail (e.g., divers' expertise, size and distance between groups of divers, accessibility, wind, coral coverage). The TCC values ranged between 1,252 and 1,642 dives/year/trail, with a total of 8,597 dives/year for all six trails. Although these numbers are higher than the actual number of recreational visitors to the island (~1,000 dives per year), there is a need for adequate preventive management if the diving sites are to maintain their esthetic appeal and biological characteristics. Such management might be initially directed toward using only the sites and the TCC proposed here.

  10. Biofilm growth mode promotes maximum carrying capacity and community stability during product inhibition syntrophy

    Directory of Open Access Journals (Sweden)

    Kristen Annis Brileya

    2014-12-01

    Full Text Available Sulfate-reducing bacteria (SRB can interact syntrophically with other community members in the absence of sulfate, and interactions with hydrogen-consuming methanogens are beneficial when these archaea consume potentially inhibitory H2 produced by the SRB. A dual continuous culture approach was used to characterize population structure within a syntrophic biofilm formed by the SRB Desulfovibrio vulgaris Hildenborough and the methanogenic archaeum Methanococcus maripaludis. Under the tested conditions, monocultures of D. vulgaris formed thin, stable biofilms, but monoculture M. maripaludis did not. Microscopy of intact syntrophic biofilm confirmed that D. vulgaris formed a scaffold for the biofilm, while intermediate and steady-state images revealed that M. maripaludis joined the biofilm later, likely in response to H2 produced by the SRB. Close interactions in structured biofilm allowed efficient transfer of H2 to M. maripaludis, and H2 was only detected in cocultures with a mutant SRB that was deficient in biofilm formation ( delta pilA. M. maripaludis produced more carbohydrate (uronic acid, hexose, and pentose as a monoculture compared to total coculture biofilm, and this suggested an altered carbon flux during syntrophy. The syntrophic biofilm was structured into ridges (~300 x 50 um and models predicted lactate limitation at approximately 50 um biofilm depth. The biofilm had structure that likely facilitated mass transfer of H2 and lactate, yet maximized biomass with a more even population composition (number of each organism when compared to the bulk-phase community. Total biomass protein was equivalent in lactate-limited and lactate-excess conditions when a biofilm was present, but in the absence of biofilm, total biomass protein was significantly reduced. The results suggest that multispecies biofilms create an environment conducive to resource sharing, resulting in increased biomass retention, or carrying capacity, for cooperative

  11. Psychophysical determination of load carrying capacity for a 1-h work period by Chinese males.

    Science.gov (United States)

    Wu, S P; Chen, C C

    2001-09-15

    This study used the psychophysical approach to examine the effects of container width, the presence or absence of container handles, and different load-carrying frequencies and distances on the maximum acceptable weight carried and the resulting response (heart rate and rating of perceived exertion) by well-conditioned males for a 1-h work period. After training, 12 male subjects performed a load-carrying task at knuckle height. Each subject performed 30 different carrying combinations. The conditions examined were container width, from 15.2 to 55.9 cm; carrying frequency, from 1 carry to 5 carries/min; and carrying distance from 1 to 6 m. The results were compared with prior studies and led to the following conclusions: (1) the use of container handles leads to the subjects carrying a significantly higher maximum acceptable weight than when containers do not have handles, which differs from the results of a previous study by Morrissey and Liou; (2) there were significant reductions in the maximum acceptable carrying weight with increases in container width, frequency and distance; (3) the presence or absence of container handles, different frequencies and load-carrying distances had significant effects on heart rate, although the effect of container width was not significant. In addition, the various frequencies and distances for load carrying had significant interaction effects on heart rate; (4) the effects of various frequencies and load-carrying distances on the rating of perceived exertion were statistically significant. The most stressed body parts were the wrists and arms.

  12. Climate change is projected to reduce carrying capacity and redistribute species richness in North Pacific pelagic marine ecosystems.

    Science.gov (United States)

    Woodworth-Jefcoats, Phoebe A; Polovina, Jeffrey J; Drazen, Jeffrey C

    2017-03-01

    Climate change is expected to impact all aspects of marine ecosystems, including fisheries. Here, we use output from a suite of 11 earth system models to examine projected changes in two ecosystem-defining variables: temperature and food availability. In particular, we examine projected changes in epipelagic temperature and, as a proxy for food availability, zooplankton density. We find that under RCP8.5, a high business-as-usual greenhouse gas scenario, increasing temperatures may alter the spatial distribution of tuna and billfish species richness across the North Pacific basin. Furthermore, warmer waters and declining zooplankton densities may act together to lower carrying capacity for commercially valuable fish by 2-5% per decade over the 21st century. These changes have the potential to significantly impact the magnitude, composition, and distribution of commercial fish catch across the pelagic North Pacific. Such changes will in turn ultimately impact commercial fisheries' economic value. Fishery managers should anticipate these climate impacts to ensure sustainable fishery yields and livelihoods.

  13. Changes in agriculture and abundance of snow geese affect carrying capacity of sandhill cranes in Nebraska

    Science.gov (United States)

    Pearse, A.T.; Krapu, G.L.; Brandt, D.A.; Kinzel, P.J.

    2010-01-01

    The central Platte River valley (CPRV) in Nebraska, USA, is a key spring-staging area for approximately 80 of the midcontinent population of sandhill cranes (Grus canadensis; hereafter cranes). Evidence that staging cranes acquired less lipid reserves during the 1990s compared to the late 1970s and increases in use of the CPRV by snow geese (Chen caerulescens) prompted us to investigate availability of waste corn and quantify spatial and temporal patterns of crane and waterfowl use of the region. We developed a predictive model to assess impacts of changes in availability of corn and snow goose abundance under past, present, and potential future conditions. Over a hypothetical 60-day staging period, predicted energy demand of cranes and waterfowl increased 87 between the late 1970s and 19982007, primarily because peak abundances of snow geese increased by 650,000 and cranes by 110,000. Compared to spring 1979, corn available when cranes arrived was 20 less in 1998 and 68 less in 1999; consequently, the area of cornfields required to meet crane needs increased from 14,464 ha in 1979 to 32,751 ha in 1998 and 90,559 ha in 1999. Using a pooled estimate of 88 kg/ha from springs 19981999 and 20052007, the area of cornfields needed to supply food requirements of cranes and waterfowl increased to 65,587 ha and was greatest in the eastern region of the CPRV, where an estimated 54 of cranes, 47 of Canada geese (Branta canadensis), 45 of greater white-fronted geese (Anser albifrons), and 46 of snow geese occurred during ground surveys. We estimated that a future reduction of 25 in available corn or cornfields would increase daily foraging flight distances of cranes by 2738. Crane use and ability of cranes to store lipid reserves in the CPRV could be reduced substantially if flight distance required to locate adequate corn exceeded a physiological maximum distance cranes could fly in search of food. Options to increase carrying capacity for cranes include increasing

  14. Strengthening Carrying Capacity of a Water Supply System under Climate Change with the Drought Early Warning System

    Science.gov (United States)

    Huang, Syujie; Liu, Tzuming; Li, Minghsu; Tung, Chingpin

    2016-04-01

    The carrying capacity of a water supply system is the maximal probable water supply amount under an acceptable risk which is related to the systematic combination of hydrology conditions, climatic conditions, and water infrastructures, for instance, reservoirs, weirs, and water treatment plants. Due to long-term imbalance of water supply and demand during the drought seasons, the carrying capacity of a water supply system may be affected gradually with more extreme climate events resulting from the climate change. To evaluate the carrying capacity of the water supply system under climate change, three major steps to build adaptation capacity under climate change are adopted, including problem identification and goal setting, current risk assessment, and future risk assessment. The carrying capacities for current climate condition and future climate condition were estimated respectively. The early warning system was taken as the effective measure to strengthen the carrying capacity for the uncertain changing climate. The water supply system of Chuoshui River basin in Taiwan is used as the case study. The system dynamics modeling software, Vensim, was used to build the water resources allocation model for Chuoshui River basin. To apply the seasonal climate forecasts released from Taiwan Central Weather Bureau (CWB) on modeling, a weather generator is adopted to generate daily weather data for the input of the hydrological component of GWLF model, to project inflows with the lead time of three months. Consequently, the water shortages with and without a drought early warning system were estimated to evaluate the effectiveness of a drought early warning system under climate change. Keywords: Climate change, Carrying capacity, Risk Assessment, Seasonal Climate Forecasts, Drought Early Warning System

  15. On Distributed PV Hosting Capacity Estimation, Sensitivity Study, and Improvement

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Fei; Mather, Barry

    2017-07-01

    This paper first studies the estimated distributed PV hosting capacities of seventeen utility distribution feeders using the Monte Carlo simulation based stochastic analysis, and then analyzes the sensitivity of PV hosting capacity to both feeder and photovoltaic system characteristics. Furthermore, an active distribution network management approach is proposed to maximize PV hosting capacity by optimally switching capacitors, adjusting voltage regulator taps, managing controllable branch switches and controlling smart PV inverters. The approach is formulated as a mixed-integer nonlinear optimization problem and a genetic algorithm is developed to obtain the solution. Multiple simulation cases are studied and the effectiveness of the proposed approach on increasing PV hosting capacity is demonstrated.

  16. Recreation Carrying Capacity Facts and Considerations. Report 11. Surry Mountain Lake Project Area.

    Science.gov (United States)

    1980-07-01

    examines possible solutions; and it does not include the methodologies for deter- mining and monitoring social and resource capacity. For these reasons...Point Overcrowding observed and o Determine social capac- Picnic Areas reported during the User Survey. ity of these areas. o Place only the...area. r Consider the potential for site hardening and provide agressive maintenancce and restiration. 40 Possible Area/Subject Problem/Situation

  17. Conceptual Framework of Tourism Carrying Capacity for a Tourism City: Experiences from National Parks in the United States

    Institute of Scientific and Technical Information of China (English)

    Zheng Nasha; Zheng Xilai

    2010-01-01

    There is no universally-accepted definition of tourism carrying capacity(TCC).Numerical TCC focuses on use level and is considered as"a magic number"of the saturation point for tourism.There are several reasons why numerical tourism capacity is inadequate.Alternatively,tourism capacity can be defined in terms of limits of acceptable change,which shifts the focus from"how much use is too much"to"how much change is acceptable".This article proposes an improved conceptual framework for evaluating carrying capacity for the tourism city based on approaches used in US national parks,which consider the impact of human use on a city's economic,environmental/resource,and socio-cultural conditions.Based on the basic data of indicator values and relevant standards,the framework monitors the current indicators and predicts future indicator values; it can also be used to assess and predict TCC.

  18. RESEARCH ON THE POPULATION CARRYING CAPACITY OF THE LAND RESOURCES IN THE ECONOMIC AREA OF ZHUJIANG DELTA

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The authors once made a preliminary research on population carrying capacity of the land in the Economic Area of Zhujiang Delta (EAZD for short) in 1995, and reckoned that the ultimate population in this region will be 23 550 thousand by year of 2000. While the population in being in EAZD was 22.62 million in 1999. This accords with the prefigured result in the rough from the point of view of development. According to the data of plow land resources from the 2000 Statistical Yearbook of EAZD and the study on the population-foodstuff-plow land relationship, this paper calculates the productive potential of plow land and the population carrying capacity of land by year of 2010, and puts forward the countermeasures for improving the population carrying capacity of land in this region.

  19. Simple Evaluation of Load-Carrying Capacity of Multi-Span Folding Bridges based on Floating Supports

    Directory of Open Access Journals (Sweden)

    Jan Marszałek

    2014-12-01

    Full Text Available [b]Abstract[/b]. The papers covers simple evaluation of load-carrying capacity of multi-span folding bridges based on floating supports. Combined bridges built in this approach, could be used as a temporary crossing. The methodology of this evaluation is shown graphically on the basis of designed nomograms for two existing bridge structures i.e. MS-54 and DMS-65, mounted on rigid and floating supports. These nomograms facilitate the simple and fast determination of the impact of changing fixed support into floating support with different bridge length spans on the carrying capacity of the bridge. The paper also presents the influence of long-term use (enlarging the mounting backlash in the joints of these structures on the carrying capacity of the bridge.[b]Keywords[/b]: building, folding bridges, nomograms, assembly clearances

  20. Glove powder's carrying capacity for latex protein: analysis using the ASTM ELISA test.

    Science.gov (United States)

    Beezhold, D; Horton, K; Hickey, V; Daddona, J; Kostyal, D

    2003-01-01

    Glove donning powders carry latex proteins and disperse them into the workplace environment. We have used the ASTM D6499 ELISA to quantify the amount of latex antigen bound to and carried by glove powders. We could differentiate between a small amount of protein actually bound to the powders and a larger amount carried by the powder. Enhanced binding of a major allergen, Hev b 5, to the starch powders was demonstrated by Western blot. The D6499 ELISA is able to measure total latex antigen, soluble and powder bound, simultaneously without the need to centrifuge the samples.

  1. Load-carrying capacity test of a long-span timber truss

    OpenAIRE

    Branco, Jorge M.; Varum, Humberto; Ramisote, Vitor; Costa, Aníbal

    2016-01-01

    The aim of this work was to study the behavior of existing timber trusses in order to improve the knowledge that may support engineers in the definition of more adequate restoration interventions in old buildings, particularly of long-span timber structures, as industrial or monumental constructions. For this purpose, a cyclic load-carrying test was carried out on a full-scale timber planar truss rescued from an old industrial roof structure. Before the tests, an accurate geometrical characte...

  2. Technologies to Increase PV Hosting Capacity in Distribution Feeders: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Fei; Mather, Barry; Gotseff, Peter

    2016-08-01

    This paper studies the distributed photovoltaic (PV) hosting capacity in distribution feeders by using the stochastic analysis approach. Multiple scenario simulations are conducted to analyze several factors that affect PV hosting capacity, including the existence of voltage regulator, PV location, the power factor of PV inverter and Volt/VAR control. Based on the conclusions obtained from simulation results, three approaches are then proposed to increase distributed PV hosting capacity, which can be formulated as the optimization problem to obtain the optimal solution. All technologies investigated in this paper utilize only existing assets in the feeder and therefore are implementable for a low cost. Additionally, the tool developed for these studies is described.

  3. Technologies to Increase PV Hosting Capacity in Distribution Feeders

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Fei; Mather, Barry; Gotseff, Peter

    2016-11-14

    This paper studies the distributed photovoltaic (PV) hosting capacity in distribution feeders by using the stochastic analysis approach. Multiple scenario simulations are conducted to analyze several factors that affect PV hosting capacity, including the existence of voltage regulator, PV location, the power factor of PV inverter and Volt/VAR control. Based on the conclusions obtained from simulation results, three approaches are then proposed to increase distributed PV hosting capacity, which can be formulated as the optimization problem to obtain the optimal solution. All technologies investigated in this paper utilize only existing assets in the feeder and therefore are implementable for a low cost. Additionally, the tool developed for these studies is described.

  4. A Study on Load Carrying Capacity of Fly Ash Based Polymer Concrete Columns Strengthened Using Double Layer GFRP Wrapping

    Directory of Open Access Journals (Sweden)

    S. Nagan

    2014-01-01

    Full Text Available This paper investigates the suitability of glass fiber reinforced polymer (GFRP sheets in strengthening of fly ash based polymer members under compression. Experimental results revealed that load carrying capacity of the confined columns increases with GFRP sheets wrapping. Altogether 18 specimens of M30 and G30 grade short columns were fabricated. The G30 specimens were prepared separately in 8 molarity and 12 molarity of sodium hydroxide concentration. Twelve specimens for low calcium fly ash based reinforced polymer concrete and six specimens of ordinary Portland cement reinforced concrete were cast. Three specimens from each molarity fly ash based reinforced polymer concrete and ordinary Portland cement reinforced concrete were wrapped with double layer of GFRP sheets. The load carrying capacity of fly ash based polymer concrete was tested and compared with control specimens. The results show increase in load carrying capacity and ductility index for all strengthened elements. The maximum increase in load carrying capacity was 68.53% and is observed in strengthened G30 specimens.

  5. Alveolar gas exchange and tissue oxygenation during incremental treadmill exercise, and their associations with blood O(2) carrying capacity.

    Science.gov (United States)

    Rissanen, Antti-Pekka E; Tikkanen, Heikki O; Koponen, Anne S; Aho, Jyrki M; Hägglund, Harriet; Lindholm, Harri; Peltonen, Juha E

    2012-01-01

    The magnitude and timing of oxygenation responses in highly active leg muscle, less active arm muscle, and cerebral tissue, have not been studied with simultaneous alveolar gas exchange measurement during incremental treadmill exercise. Nor is it known, if blood O(2) carrying capacity affects the tissue-specific oxygenation responses. Thus, we investigated alveolar gas exchange and tissue (m. vastus lateralis, m. biceps brachii, cerebral cortex) oxygenation during incremental treadmill exercise until volitional fatigue, and their associations with blood O(2) carrying capacity in 22 healthy men. Alveolar gas exchange was measured, and near-infrared spectroscopy (NIRS) was used to monitor relative concentration changes in oxy- (Δ[O(2)Hb]), deoxy- (Δ[HHb]) and total hemoglobin (Δ[tHb]), and tissue saturation index (TSI). NIRS inflection points (NIP), reflecting changes in tissue-specific oxygenation, were determined and their coincidence with ventilatory thresholds [anaerobic threshold (AT), respiratory compensation point (RC); V-slope method] was examined. Blood O(2) carrying capacity [total hemoglobin mass (tHb-mass)] was determined with the CO-rebreathing method. In all tissues, NIPs coincided with AT, whereas RC was followed by NIPs. High tHb-mass associated with leg muscle deoxygenation at peak exercise (e.g., Δ[HHb] from baseline walking to peak exercise vs. tHb-mass: r = 0.64, p capacity for blood O(2) carrying was associated with a high level of m. vastus lateralis deoxygenation at peak exercise.

  6. Influence of wave and current flow on sediment-carrying capacity and sediment flux at the water-sediment interface.

    Science.gov (United States)

    Zheng, Jun; Li, Ruijie; Yu, Yonghai; Suo, Anning

    2014-01-01

    In nearshore waters, spatial and temporal scales of waves, tidal currents, and circulation patterns vary greatly. It is, therefore, difficult to combine these factors' effects when trying to predict sediment transport processes. This paper proposes the concept of significant wave velocity, which combines the effects of waves, tides, and ocean currents using the horizontal kinetic energy superposition principle. Through a comparison of the relationship between shear stress at the water-sediment interface and sediment-carrying capacity, assuming equilibrium sediment flux, a new formula for sediment-carrying capacity, which incorporates the concept of significant wave velocities, is derived. Sediment-carrying capacity is a function of the critical velocity, which increases with water depth and decreases with increasing relative roughness of the sea bed. Finally, data from field observation stations and simulations are used to test the proposed formula. The results show that the new formula is in good agreement with both field and simulation data. This new formula for sediment-carrying capacity can be used to simulate nearshore sediment transport.

  7. Student Responses to a Hands-On Kinesthetic Lecture Activity for Learning about the Oxygen Carrying Capacity of Blood

    Science.gov (United States)

    Breckler, Jennifer; Yu, Justin R.

    2011-01-01

    This article describes a new hands-on, or "kinesthetic," activity for use in a physiology lecture hall to help students comprehend an important concept in cardiopulmonary physiology known as oxygen carrying capacity. One impetus for designing this activity was to address the needs of students who have a preference for kinesthetic…

  8. Population ecology and carrying capacity estimates for large ungulates at Sully's Hill National Game Preserve, North Dakota

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a proposal for a two year project with the University of North Dakota. The end product of this research will be a detailed model of the carrying capacity for...

  9. 49 CFR 571.120 - Tire selection and rims and motor home/recreation vehicle trailer load carrying capacity...

    Science.gov (United States)

    2010-10-01

    ... words “IMPORTANT—USE OF SPARE TIRE” in letters not less than 9 millimeters high. S8.2Supplementary... of on-board potable water must be treated as cargo. S10.4.3The RV load carrying capacity labels... belt equipped seating positions. (e) The statement: “CAUTION: A full load of water equals XXX kg or XXX...

  10. Parametrical Method for Determining Optimal Ship Carrying Capacity and Performance of Handling Equipment

    Directory of Open Access Journals (Sweden)

    Michalski Jan P.

    2016-04-01

    Full Text Available The paper presents a method of evaluating the optimal value of the cargo ships deadweight and the coupled optimal value of cargo handling capacity. The method may be useful at the stage of establishing the main owners requirements concerning the ship design parameters as well as for choosing a proper second hand ship for a given transportation task. The deadweight and the capacity are determined on the basis of a selected economic measure of the transport effectiveness of ship – the Required Freight Rate. The mathematical model of the problem is of a deterministic character and the simplifying assumptions are justified for ships operating in the liner trade. The assumptions are so selected that solution of the problem is obtained in analytical closed form. The presented method can be useful for application in the preliminary ship design or in the simulation of pre-investment transportation task studies.

  11. Load Carrying Capacity of Keyed Joints Reinforced with High Strength Wire Rope Loops

    DEFF Research Database (Denmark)

    Jørgensen, Henrik Brøner; Hoang, Linh Cao

    Vertical shear connections between precast concrete wall elements are usually made as keyed joints reinforced with overlapping U-bars. The overlapping U-bars form a cylindrical core in which the locking bar is placed and the connection is subsequently grouted with mortar. A more construction...... friendly shear connection can be obtained by replacing the U-bars with high strength looped wire ropes. The wire ropes have the advantage of being flexible (they have virtually no bending stiffness) which makes installation of wall elements much easier. The looped wire ropes are usually pre-installed in so...... the shear capacity of wire loop connections. Tests have shown that the shear capacity of such joints – due to the relatively high tensile strength of the wire ropes - is more prone to be governed by fracture of the joint mortar in combination with yielding of the locking bar. To model this type of failure...

  12. Load-carrying capacity of lightly reinforced, prefabricated walls of lightweight aggregate concrete with open structure

    DEFF Research Database (Denmark)

    Goltermann, Per

    2009-01-01

    The paper presents and evaluates the results of a coordinated testing of prefabricated, lightly reinforced walls of lightweight aggregate concrete with open structure. The coordinated testing covers all wall productions in Denmark and will therefore provide a representative assessment of the qual...... of the quality actually produced. Existing and new formulas for the capacity are evaluated by comparison to the test results and a new model with a good correlation with the test results is presented....

  13. Rapid Population Growth and Human Carrying Capacity: Two Perspectives. World Bank Staff Working Papers No. 690 and Population and Development Series No. 15.

    Science.gov (United States)

    Mahar, Dennis J., Ed.; And Others

    Two perspectives on carrying capacity and population growth are examined. The first perspective, "Carrying Capacity and Rapid Population Growth: Definition, Cases, and Consequences" (Robert Muscat), explores the possible meanings of the idea of carrying capacity under developing country conditions, looks at historical and present-day cases of…

  14. Analysis of Load-Carrying Capacity for Redundant Free-Floating Space Manipulators in Trajectory Tracking Task

    Directory of Open Access Journals (Sweden)

    Qingxuan Jia

    2014-01-01

    Full Text Available The aim of this paper is to analyze load-carrying capacity of redundant free-floating space manipulators (FFSM in trajectory tracking task. Combined with the analysis of influential factors in load-carrying process, evaluation of maximum load-carrying capacity (MLCC is described as multiconstrained nonlinear programming problem. An efficient algorithm based on repeated line search within discontinuous feasible region is presented to determine MLCC for a given trajectory of the end-effector and corresponding joint path. Then, considering the influence of MLCC caused by different initial configurations for the starting point of given trajectory, a kind of maximum payload initial configuration planning method is proposed by using PSO algorithm. Simulations are performed for a particular trajectory tracking task of the 7-DOF space manipulator, of which MLCC is evaluated quantitatively. By in-depth research of the simulation results, significant gap between the values of MLCC when using different initial configurations is analyzed, and the discontinuity of allowable load-carrying capacity is illustrated. The proposed analytical method can be taken as theoretical foundation of feasibility analysis, trajectory optimization, and optimal control of trajectory tracking task in on-orbit load-carrying operations.

  15. Environment Carrying Capacity in Developing Innovation Center of Micro Small Medium Enterprises (MSME in Kabupaten Pandeglang, Banten Province

    Directory of Open Access Journals (Sweden)

    Muhlisin

    2015-03-01

    Full Text Available The study aims to determine environmental carrying capacity strategies for developing MSMEs Innovation Center. The study research using quantitative descriptive method and instruments questionnaire given to stakeholders and government related to sheep and goats in the Juhut village, Pandeglang. Data collected was processed premises scoring and Analytical Hierarchy Process (AHP method used software of expert choice 11. The results showed that the Carrying Capacity levels of MSME was in the quite category, while aspect of facilitation as the highest proportions and the lowest was access to information. Innovation Center of MSME strategies are through the efforts increased Environment Carrying Capacity’s variables of Innovation Center of MSME are still lacking or not meet the standards through synergy efforts by Ministry of Research of Technology and Higher Education, Provincial Government. Of Banten, district/municipal government, Institute for Agricultural Technology of Banten, and universities.

  16. Dynamic Changes of Land Ecological Carrying Capacity Based on the Ecological Footprint——By the Case Study of Chengdu City

    Institute of Scientific and Technical Information of China (English)

    Wenfu PENG; Xiaolan ZHONG; Qiuyang LI; Qin LI

    2012-01-01

    Chengdu City is in the period of rapid urbanization and industrialization, and the disturbance derived from human activities on environment is increasing remarkablely in recent 20 years. The pressure on environment, economy and population is also increasing and land use in Chengdu has changed enormously. As struc- ture and function of land ecological system change obviously, sustainable development of land productivity has been an important goal and strategic task from now on, and it is necessary to systematically research land ecological carrying capacity based on ecological footprint. The ecological footprint of Chengdu City in the past ten years was calculated and analyzed from the spatial and temporal aspects according to statistical data from 1998 to 2008, as per ecological footprint method, ecological carrying capacity and the GIS spatial analysis method, and regression analysis method. The ecological footprint and ecological carrying capacity values from 2009 to 2019 in Chengdu City were predicted through calculation results in the past ten years. The results show that the ecological footprint and ecological deficit of land use from 1998 to 2008 increased in Chengdu City. The ecological deficit of land use within the city center was in high levels in the past ten years, and the ecological footprint kept raising, especially in areas, such as Shuangliu, Chongzhou, Qingyang among 9 city areas, 4 counties and 6 districts in Chengdu City. There is fanlike distribution of ecological deficit of land use. Analysis shows that the social and natural ecological system is uneven distribution, which is not in sustainable de- velopment situation. The results of the study show that the economic, social and natural ecological system in Chengdu City is not sustainable, and the ecological foot- print is uneven distribution. The analysis of the dynamic change of land ecological carrying capacity in Chengdu City is very important for city government in the pro- cess of the

  17. Natural Airfield Pavements, Load-Carrying Capacities There Of, Principles Of Construction And Operational Use

    Directory of Open Access Journals (Sweden)

    Nita Piotr

    2015-09-01

    Full Text Available The paper has been intended to present analytically derived relationships for aircraft wheels that move through the soil medium. The analyses have been conducted for both the rigid wheel and the pneumatic whell. The most fundamental principles of constructing natural(soil and sod/grass airfield pavements have been diccussed. Characteristic of soils typical of such pavements /surfaces have been defined. Proped are criteria for the evaluation of load-carring capacities of such pavements. The most essential principles that goven the operational use there of follow.

  18. Numerical study of regional environmental carrying capacity for livestock and poultry farming based on planting-breeding balance.

    Science.gov (United States)

    Peng, Lihong; Bai, Yu

    2013-09-01

    In consideration of the need to maintain planting-breeding balance, this article examines the capacity of the soil in Putian City, Fujian Province to absorb livestock and poultry excreta, and computes the environmental carrying capacity for livestock and poultry farming (ECCLPF) in each district of the city in terms of the fertility characteristics of the soil in the city, as well as its mix of crops cultivated and farming methods. On the basis of the computations, this work proceeds to classify the alarm grades of the city's environmental carrying capacity for livestock and poultry framing, and assess the environmental impact of the livestock and poultry farming industry. The results of our study indicate that, the city's ECCLPF ranges from 8.27 to 23.23 heads per ha when computed on the basis of nitrogen, and from 5.79 to 24.53 heads per ha when computed on the basis of phosphorus. A comparison between our research findings and the existing farming scale in Putian reveals that, in certain parts of the city, ECCLPF is overburdened to varying degrees. Specifically, Chengxiang District is severely overburdened, Hanjiang District and Meizhou Island have a level of overburdening between virtual overburdening and significant overburdening, Licheng District is virtually overburdened, and Xiuyu, Xianyou, and Bei'an Districts have not exceeded their environmental carrying capacity and therefore have varying levels of potential for growth.

  19. Numerical study of regional environmental carrying capacity for livestock and poultry farming based on planting-breeding balance

    Institute of Scientific and Technical Information of China (English)

    Lihong Peng; Yu Bai

    2013-01-01

    In consideration of the need to maintain planting-breeding balance,this article examines the capacity of the soil in Putian City,Fujian Province to absorb livestock and poultry excreta,and computes the environmental carrying capacity for livestock and poultry farming (ECCLPF) in each district of the city in terms of the fertility characteristics of the soil in the city,as well as its mix of crops cultivated and farming methods.On the basis of the computations,this work proceeds to classify the alarm grades of the city's environmental carrying capacity for livestock and poultry framing,and assess the environmental impact of the livestock and poultry farming industry.The results of our study indicate that,the city's ECCLPF ranges from 8.27 to 23.23 heads per ha when computed on the basis of nitrogen,and from 5.79 to 24.53 heads per ha when computed on the basis of phosphorus.A comparison between our research findings and the existing fanning scale in Putian reveals that,in certain parts of the city,ECCLPF is overburdened to varying degrees.Specifically,Chengxiang District is severely overburdened,Hanjiang District and Meizhou Island have a level of overburdening between virtual overburdening and significant overburdening,Licheng District is virtually overburdened,and Xiuyu,Xianyou,and Bei'an Districts have not exceeded their environmental carrying capacity and therefore have varying levels of potential for growth.

  20. Calculating the Carrying Capacity of Flexural Prestressed Concrete Beams with Non-Metallic Reinforcement

    Directory of Open Access Journals (Sweden)

    Mantas Atutis

    2011-04-01

    Full Text Available The article reviews moment resistance design methods of prestressed concrete beams with fibre-reinforced polymer (FRP reinforcement. FRP tendons exhibit linear elastic response to rupture without yielding and thus failure is expected to be brittle. The structural behaviour of beams prestressed with FRP tendons is different from beams with traditional steel reinforcement. Depending on the reinforcement ratio, the flexural behaviour of the beam can be divided into several groups. The numerical results show that depending on the nature of the element failure, moment resistance calculation results are different by using reviewed methods. It was found, that the use of non-metallic reinforcement in prestressed concrete structures is effective: moment capacity is about 5% higher than that of the beams with conventional steel reinforcement.Article in Lithuanian

  1. Capacity of Distribution Feeders for Hosting Distributed Energy Resources

    DEFF Research Database (Denmark)

    Papathanassiou, S.; Hatziargyriou, N.; Anagnostopoulos, P.

    The last two decades have seen an unprecedented development of distributed energy resources (DER) all over the world. Several countries have adopted a variety of support schemes (feed-in tariffs, green certificates, direct subsidies, tax exemptions etc.) so as to promote distributed generation (DG...

  2. Peculiarities of carrying capacity evaluations of cylindrical CFST columns with new type casing

    Directory of Open Access Journals (Sweden)

    Sinkovskaya Olena

    2017-01-01

    Full Text Available This paper deals with a cylindrical steel-concrete load-bearing unit. The feature of the unit is a steel mesh casing that is made from the expanded metal mesh. The optimal parameters of the suggested footing are determined taking into account anisotropy, i. e. different strength and rigidity in different directions that coincide and do not coincide with the direction of reinforcement. The optimal cell angle, when a casing deformation brings about maximum compression of a concrete core, is determined. Details for theoretical calculation of the bearing capacity of a cylindrical steel-concrete load-bearing unit are provided taking into consideration a complex three-dimensional structure of the suggested mesh casing. The validity of the calculations is confirmed by comparison them with the results of the Lira software package. The results of the calculations are provided in the form of the table showing the dependence of the adduced thickness of the plate on the longitudinal movement of the strip of the steel mesh casing. The dependencies to determine the adduced thickness of the mesh casing using the graphical method are provided for all the existing types of the mesh using concrete wedges or excluding them.

  3. Field Carrying Capacity Analysis of Agricultural Sector Based Spatial in Nagari Taram, District of Lima Puluh Kota, West Sumatra

    Directory of Open Access Journals (Sweden)

    Ernamaiyanti Ernamaiyanti

    2016-06-01

    Full Text Available Land conversion has changed the field carryng capacity and filed quality. The purpose of this study is to figured out of field wideness Nagari Taram, and to analyze the availability and suitability of agricultural land Nagari Taram. Analysis of Field carrying capacity based on the Regulation of the Minister of Environment No. 17 of 2009, following by Focus Group Discussion (FGD and analytic hierarchy process (AHP. The results, agricultural land based on type of ecosystem in the by area Nagari Taram is 1003.5 hectares consisting rice fields, dry land, ponds and open waters. Availability of agricultural land Nagari Taram is a surplus. stability of Nagari Taram slopes are low, high, less and medium. analysis showing field carrying suitability Nagari Taram is suitable for land agricultural.

  4. Thermal shaft effects on load-carrying capacity of a fully coupled, variable-properties cryogenic journal bearing

    Science.gov (United States)

    Braun, M. J.; Wheeler, R. L., III; Hendricks, R. C.

    1986-01-01

    The purpose of this work was to perform a rather complete analysis for a cryogenic (oxygen) journal bearing. The Reynolds equation required coupling and simultaneous solution with the fluid energy equation. To correctly account for the changes in the fluid viscosity, the fluid energy equation was coupled with the shaft and bearing heat conduction energy equations. The effects of pressure and temperature on the density, viscosity, and load-carrying capacity were further discussed as analysis parameters, with respect to relative eccentricity and the angular velocity. The isothermal fluid case and the adiabatic fluid case represented the limiting boundaries. The discussion was further extrapolated to study the Sommerfeld number dependency on the fluid Nusselt number and its consequence on possible total loss of load-carrying capacity and/or seizure (catastrophic failure).

  5. Simultaneous Optimization of Tooth Flank Form of Involute Helical Gears in Terms of Both Vibration and Load Carrying Capacity

    Science.gov (United States)

    Komori, Masaharu; Kubo, Aizoh; Suzuki, Yoshitomo

    The alignment condition of automotive gears changes considerably during operation due to the deformation of shafts, bearings, and gear box by transmission of load. Under such conditions, the gears are required to satisfy not only reliability in strength and durability under maximum loading conditions, but also low vibrational characteristics under light loading conditions during the cruising of a car. In this report, the characteristics of the optimum tooth flank form of gears in terms of both vibration and load carrying capacity are clarified. The local optimum tooth flank form appears in each excitation valley, where the vibrational excitation is low and the actual contact ratio takes a specific value. The influence of the choice of different local optimum solutions on the vibrational performance of the optimized gears is investigated. The practical design algorithm for the optimum tooth flank form of a gear set in terms of both vibration and load carrying capacity is then proposed and its result is evaluated by field experience.

  6. Load carrying capacity of shear wall t-connections reinforced with high strength wire ropes

    DEFF Research Database (Denmark)

    Jørgensen, Henrik B.; Bryndom, Thor; Larsen, Michael

    2016-01-01

    Traditionally, U-bar loop connections with keyed joints have been used in vertical shear connections between precast concrete wall elements. However, in the recent years, connections with looped high strength wire ropes instead of U-bar loops have proven to be a much more construction......-friendly solution. The wire ropes have no bending stiffness and therefore allow for an easier vertical installation of the wall elements. During the last 10 – 15 years, a number of shear tests on plane wire rope connections have been carried out. However, to the best knowledge of the authors, tests on wire rope...... connections for assembly of precast elements in different planes, such as T- and L-connections, have not yet been published. This paper presents the results of a large test series recently conducted at the University of Southern Denmark to study the shear behaviour of high strength wire rope T...

  7. Load Carrying Capacity of Shear Wall T-Connections Reinforced with High Strength Wire Ropes

    DEFF Research Database (Denmark)

    Jørgensen, Henrik Brøner; Bryndum, Thor; Larsen, Michael

    2017-01-01

    Traditionally, U-bar loop connections with keyed joints have been used in vertical shear connections between precast concrete wall elements. However, in the recent years, connections with looped high strength wire ropes instead of U-bar loops have proven to be a much more construction......-friendly solution. The wire ropes have no bending stiffness and therefore allow for an easier vertical installation of the wall elements. During the last 10 – 15 years, a number of shear tests on plane wire rope connections have been carried out. However, to the best knowledge of the authors, tests on wire rope...... connections for assembly of precast elements in different planes, such as T- and L-connections, have not yet been published. This paper presents the results of a large test series recently conducted at the University of Southern Denmark to study the shear behaviour of high strength wire rope T...

  8. Alveolar gas exchange and tissue oxygenation during incremental treadmill exercise, and their associations with blood O2 carrying capacity

    Directory of Open Access Journals (Sweden)

    Antti-Pekka E. Rissanen

    2012-07-01

    Full Text Available The magnitude and timing of oxygenation responses in highly active leg muscle, less active arm muscle, and cerebral tissue, have not been studied with simultaneous alveolar gas exchange measurement during incremental treadmill exercise. Nor is it known, if blood O2 carrying capacity affects the tissue-specific oxygenation responses. Thus, we investigated alveolar gas exchange and tissue (m. vastus lateralis, m. biceps brachii, cerebral cortex oxygenation during incremental treadmill exercise until volitional fatigue, and their associations with blood O2 carrying capacity in 22 healthy men. Alveolar gas exchange was measured, and near-infrared spectroscopy (NIRS was used to monitor relative concentration changes in oxy- (Δ[O2Hb], deoxy- (Δ[HHb] and total hemoglobin (Δ[tHb], and tissue saturation index (TSI. NIRS inflection points (NIP, reflecting changes in tissue-specific oxygenation, were determined and their coincidence with ventilatory thresholds (anaerobic threshold (AT, respiratory compensation point (RC; V-slope method was examined. Blood O2 carrying capacity (total hemoglobin mass (tHb-mass was determined with the CO-rebreathing method. In all tissues, NIPs coincided with AT, whereas RC was followed by NIPs. High tHb-mass associated with leg muscle deoxygenation at peak exercise (e.g., Δ[HHb] from baseline walking to peak exercise vs. tHb-mass: r = 0.64, p < 0.01, but not with arm muscle- or cerebral deoxygenation. In conclusion, regional tissue oxygenation was characterized by inflection points, and tissue oxygenation in relation to alveolar gas exchange during incremental treadmill exercise resembled previous findings made during incremental cycling. It was also found out, that O2 delivery to less active m. biceps brachii may be limited by an accelerated increase in ventilation at high running intensities. In addition, high capacity for blood O2 carrying was associated with a high level of m. vastus lateralis deoxygenation at peak

  9. Lateral load-carrying capacity analyses of composite shear walls with double steel plates and filled concrete with binding bars

    Institute of Scientific and Technical Information of China (English)

    周德源; 刘凌飞; 朱立猛

    2016-01-01

    A method is developed to predict the lateral load-carrying capacity of composite shear walls with double steel plates and filled concrete with binding bars (SCBs). Nonlinear finite element models of SCBs were established by using the finite element tool, Abaqus. Tie constraints were used to connect the binding bars and the steel plates. Surface-to-surface contact provided by the Abaqus was used to simulate the interaction between the steel plate and the core concrete. The established models could predict the lateral load-carrying capacity of SCBs with a reasonable degree of accuracy. A calculation method was developed by superposition principle to predict the lateral load-carrying capacity of SCBs for the engineering application. The concrete confined by steel plates and binding bars is under multi-axial compression; therefore, its shear strength was calculated by using the Guo-Wang concrete failure criterion. The shear strength of the steel plates of SCBs was calculated by using the von Mises yielding criterion without considering buckling. Results of the developed method are in good agreement with the testing and finite element results.

  10. [Ecological carrying capacity of Chinese shrimp stock enhancement in Laizhou Bay of East China based on Ecopath model].

    Science.gov (United States)

    Lin, Qun; Li, Xian-sen; Li, Zhong-yi; Jin, Xian-shi

    2013-04-01

    Stock enhancement is an important way of fishery resources conservation, which can increase the high quality fishery resources and improve the fish population structure. The study of ecological carrying capacity is the premise for the scientific implementation of stock enhancement. Based on the survey data of the fishery resources and ecological environment in Laizhou Bay from 2009 to 2010, an Ecopath mass-balance model of the Laizhou Bay ecosystem consisted of 26 functional groups was constructed, and applied to analyze the overall characteristics of the ecosystem, the trophic interrelationships, and the keystone species, and to calculate the ecological carrying capacity of Chinese shrimp enhancement. As for the overall characteristics of the ecosystem, the total primary production/total respiration (TPP/TR) was 1. 53, total primary production/total biomass (TPP/B) was 24.54, Finn' s cycling index was lower (0.07), surplus production was higher (434. 41 t km-2 a-1 ), and system connectance index was lower (0. 29), indicating that this ecosystem was at an early development stage. The analysis on the keystone species showed that Chinese shrimp was not a keystone species of this ecosystem. At present, the biomass of Chinese shrimp in the ecosystem was 0. 1143 t km-2, with a greater potential of continued enhancement. It did not exceed the ecological carrying capacity of 2. 9489 t km-2 when the biomass of the Chinese shrimp was increased by 25. 8 times.

  11. The uncertain role of diversity dependence in species diversification and the need to incorporate time-varying carrying capacities.

    Science.gov (United States)

    Marshall, Charles R; Quental, Tiago B

    2016-04-01

    There is no agreement among palaeobiologists or biologists as to whether, or to what extent, there are limits on diversification and species numbers. Here, we posit that part of the disagreement stems from: (i) the lack of explicit criteria for defining the relevant species pools, which may be defined phylogenetically, ecologically or geographically; (ii) assumptions that must be made when extrapolating from population-level logistic growth to macro-evolutionary diversification; and (iii) too much emphasis being placed on fixed carrying capacities, rather than taking into account the opportunities for increased species richness on evolutionary timescales, for example, owing to increased biologically available energy, increased habitat complexity and the ability of many clades to better extract resources from the environment, or to broaden their resource base. Thus, we argue that a more effective way of assessing the evidence for and against the ideas of bound versus unbound diversification is through appropriate definition of the relevant species pools, and through explicit modelling of diversity-dependent diversification with time-varying carrying capacities. Here, we show that time-varying carrying capacities, either increases or decreases, can be accommodated through changing intrinsic diversification rates (diversity-independent effects), or changing the effects of crowding (diversity-dependent effects).

  12. Influence of local carrying capacity restrictions on stochastic predator-prey models

    Energy Technology Data Exchange (ETDEWEB)

    Washenberger, Mark J [Department of Physics and Center for Stochastic Processes in Science and Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0435 (United States); Mobilia, Mauro [Arnold Sommerfeld Center for Theoretical Physics and Center for NanoScience, Department of Physics, Ludwig-Maximilians-Universitaet Muenchen, D-80333 Munich (Germany); Taeuber, Uwe C [Department of Physics and Center for Stochastic Processes in Science and Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0435 (United States)

    2007-02-14

    We study a stochastic lattice predator-prey system by means of Monte Carlo simulations that do not impose any restrictions on the number of particles per site, and discuss the similarities and differences of our results with those obtained for site-restricted model variants. In accord with the classic Lotka-Volterra mean-field description, both species always coexist in two dimensions. Yet competing activity fronts generate complex, correlated spatio-temporal structures. As a consequence, finite systems display transient erratic population oscillations with characteristic frequencies that are renormalized by fluctuations. For large reaction rates, when the processes are rendered more local, these oscillations are suppressed. In contrast with the site-restricted predator-prey model, we also observe species coexistence in one dimension. In addition, we report results on the steady-state prey age distribution.

  13. Optimization and capacity expansion of a water distribution system

    Science.gov (United States)

    Hsu, Nien-Sheng; Cheng, Wei-Chen; Cheng, Wen-Ming; Wei, Chih-Chiang; Yeh, William W.-G.

    2008-05-01

    This paper develops an iterative procedure for capacity expansion studies for water distribution systems. We propose a methodology to analyze an existing water distribution system and identify the potential bottlenecks in the system. Based on the results, capacity expansion alternatives are proposed and evaluated for improving the efficiency of water supply. The methodology includes a network flow based optimization model, four evaluation indices, and a series of evaluation steps. We first use a directed graph to configure the water distribution system into a network. The network flow based model optimizes the water distribution in the system so that different expansion alternatives can be evaluated on a comparable basis. This model lends itself to linear programming (LP) and can be easily solved by a standard LP code. The results from the evaluation tool help to identify the bottlenecks in the water distribution system and provide capacity expansion alternatives. A useful complementary tool for decision making is composed of a series of evaluation steps with the bottleneck findings, capacity expansion alternatives, and the evaluation of results. We apply the proposed methodology to the Tou-Qian River Basin, located in the northern region of Taiwan, to demonstrate its applicability in optimization and capacity expansion studies.

  14. Distribution System Reliability Evaluation Taking Circuit Capacity into Consideration

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Distribution system reliability evaluation using the method ofconnectivity ignores the effect of operation constraints. This paper presents an approach that includes the effect of circuit capacity. Reliability evaluation of distribution systems with parallel circuits generally requires load flow solutions. The proposed approach combines the Z-matrix contingency method with DC load flow for a much faster direct solution. Three different methods for distribution system reliability evaluation have been incorporated into a computer program. The program was validated using two distribution systems connected to the IEEE-RTS and another sample distribution system.

  15. Hybrid Distributed Iterative Capacity Allocation over Bluetooth Network

    DEFF Research Database (Denmark)

    Son, L.T.; Schiøler, Henrik; Madsen, Ole Brun

    With the current development of mobile devices, short range wireless communications have become more and more popular, and many researches on short range wireless communications, such as Bluetooth, have gained special interests, in industry as well as in academy. This paper analyzes capacity...... allocation issues in Bluetooth network as convex optimization problem. We formulate the problem of maximizing of total network flows and minimizing the costs of flows. The hybrid distributed capacity allocation scheme is proposed as an approximated solution of the formulated problem that satisfies quality...... of service requirements and constraints in Bluetooth network, such as limited capacity, decentralized, frequent changes of topology and of capacities assigned to nodes in the network. The simulation shows that the performance of Bluetooth could be improved by applying the hybrid distributed iterative...

  16. Hybrid Distributed Iterative Capacity Allocation over Bluetooth Network

    DEFF Research Database (Denmark)

    Son, L.T.; Schiøler, Henrik; Madsen, Ole Brun

    2002-01-01

    With the current development of mobile devices, short range wireless communications have become more and more popular, and many researches on short range wireless communications, such as Bluetooth, have gained special interests, in industry as well as in academy. This paper analyzes capacity...... allocation issues in Bluetooth network as convex optimization problem. We formulate the problem of maximizing of total network flows and minimizing the costs of flows. The hybrid distributed capacity allocation scheme is proposed as an approximated solution of the formulated problem that satisfies quality...... of service requirements and constraints in Bluetooth network, such as limited capacity, decentralized, frequent changes of topology and of capacities assigned to nodes in the network. The simulation shows that the performance of Bluetooth could be improved by applying the hybrid distributed iterative...

  17. Study on tourist carrying capacity of sustainable tourism---by taking Qingliang Mountain in the south-eastern china as an example

    Science.gov (United States)

    Jin, Shenglang; Liu, Ting

    2017-05-01

    This paper analyzed measurable problems of tourist carrying capacity and then studied the corresponding measures by adopting theories and methods of environment sciences. Tourist carrying capacity of Qingliang Mountain was studied by analyzing the system of tourism environment capacity. The results showed that the level of service was 9726, which was smaller than the ecological carrying capacity of 12894. The facilities and spatial capacity were identified as key factors to limit the tourist carrying capacity in Qingliang Mountain. Some advices and measures including newly built and rebuilt basic facilities, construction of management methods for slack and peak tourist season respectively, construction of new sight spot and touring path were discussed to improve the tourist carrying capacity of Qingliang Mountain and solve the problems of overloading of tourists in the peak season.

  18. Isotopic investigation of contemporary and historic changes in penguin trophic niches and carrying capacity of the southern Indian ocean.

    Science.gov (United States)

    Jaeger, Audrey; Cherel, Yves

    2011-02-02

    A temperature-defined regime shift occurred in the 1970s in the southern Indian Ocean, with simultaneous severe decreases in many predator populations. We tested a possible biological link between the regime shift and predator declines by measuring historic and contemporary feather isotopic signatures of seven penguin species with contrasted foraging strategies and inhabiting a large latitudinal range. We first showed that contemporary penguin isotopic variations and chlorophyll a concentration were positively correlated, suggesting the usefulness of predator δ¹³C values to track temporal changes in the ecosystem carrying capacity and its associated coupling to consumers. Having controlled for the Suess effect and for increase CO₂ in seawater, δ¹³C values of Antarctic penguins and of king penguins did not change over time, while δ¹³C of other subantarctic and subtropical species were lower in the 1970s. The data therefore suggest a decrease in ecosystem carrying capacity of the southern Indian Ocean during the temperature regime-shift in subtropical and subantarctic waters but not in the vicinity of the Polar Front and in southward high-Antarctic waters. The resulting lower secondary productivity could be the main driving force explaining the decline of subtropical and subantarctic (but not Antarctic) penguins that occurred in the 1970s. Feather δ¹⁵N values did not show a consistent temporal trend among species, suggesting no major change in penguins' diet. This study highlights the usefulness of developing long-term tissue sampling and data bases on isotopic signature of key marine organisms to track potential changes in their isotopic niches and in the carrying capacity of the environment.

  19. Isotopic investigation of contemporary and historic changes in penguin trophic niches and carrying capacity of the southern Indian ocean.

    Directory of Open Access Journals (Sweden)

    Audrey Jaeger

    Full Text Available A temperature-defined regime shift occurred in the 1970s in the southern Indian Ocean, with simultaneous severe decreases in many predator populations. We tested a possible biological link between the regime shift and predator declines by measuring historic and contemporary feather isotopic signatures of seven penguin species with contrasted foraging strategies and inhabiting a large latitudinal range. We first showed that contemporary penguin isotopic variations and chlorophyll a concentration were positively correlated, suggesting the usefulness of predator δ¹³C values to track temporal changes in the ecosystem carrying capacity and its associated coupling to consumers. Having controlled for the Suess effect and for increase CO₂ in seawater, δ¹³C values of Antarctic penguins and of king penguins did not change over time, while δ¹³C of other subantarctic and subtropical species were lower in the 1970s. The data therefore suggest a decrease in ecosystem carrying capacity of the southern Indian Ocean during the temperature regime-shift in subtropical and subantarctic waters but not in the vicinity of the Polar Front and in southward high-Antarctic waters. The resulting lower secondary productivity could be the main driving force explaining the decline of subtropical and subantarctic (but not Antarctic penguins that occurred in the 1970s. Feather δ¹⁵N values did not show a consistent temporal trend among species, suggesting no major change in penguins' diet. This study highlights the usefulness of developing long-term tissue sampling and data bases on isotopic signature of key marine organisms to track potential changes in their isotopic niches and in the carrying capacity of the environment.

  20. [Assessment of ecosystem energy flow and carrying capacity of swimming crab enhancement in the Yellow River estuary and adjacent waters].

    Science.gov (United States)

    Lin Qun; Wang, Jun; Li, Zhong-yi; Wu, Qiang

    2015-11-01

    Stock enhancement is increasingly proved to be an important measure of the fishery resources conservation, and the assessment of carrying capacity is the decisive factor of the effects of stock enhancement. Meanwhile, the variations in the energy flow patterns of releasing species and ecosystem were the basis for assessing carrying capacity of stock enhancement. So, in the present study, based on the survey data collected from the Yellow River estuary and adjacent waters during 2012-2013, three Ecopath mass-balance models were established in June, August and October, and the variations in ecosystem energy flow in these months were analyzed, as well as the assessment of carrying capacity of swimming crab enhancement. The energy flow mainly concentrated on trophic level I-III in Yellow River estuary and adjacent waters, and was relatively less on trophic level IV or above. The system flow proportion on the trophic level I was the highest in June, and was the lowest in August. The highest system flow proportion on the trophic level II was found in August, and the lowest in June. The relative and absolute energy flow of swimming crab mainly concentrated on the trophic level III, and the mean trophic level of swimming crab among June, August and October were 3.28. Surplus production was relatively higher in Yellow River estuary and adjacent waters, the highest value was found in June, and the lowest value in August. The ratios of total primary production/total respiration (TPP/TR) were 5.49, 2.47 and 3.01 in June, August and October, respectively, and the ratios of total primary production/total biomass (TPP/B) were 47.61, 33.30 and 29.78, respectively. Combined with the low Finn' s cycling index (FCI: 0.03-0.06), these changes indicated that the Yellow River estuary ecosystem was at an early development stage with higher vulnerability. The energy conversion efficiency of system was from 7.3% to 11.5%, the mean trophic levels of the catch were 3.23, 2.97 and 2.82 in

  1. RESEARCH ON THE POPULATION CARRYING CAPACITY OF THE LAND RESOURCES IN THE ECONOMIC AREA OF ZHUJIANG DELTA

    Institute of Scientific and Technical Information of China (English)

    TANG; Hui-jun

    2001-01-01

    [1]Guangdong Province Statistics Bureau, 2000. The Statistic Annual of Agricultural Economy of Guangdong[Z] ) Beijing:Chinese Statistic Press, 39-40, 203-222. (in Chinese)[2]Guangdong Province Construction Committee, 1996. The Planning of Zhujiang Delta Cities[Z]. Beijing: Chinese Architecture Technology Press. (in Chinese)[3]WANG Ying-cai, ZHANG Miao-ling, 1994. Research on the Population Carrying Potentiality of the Land Resource in Jiangsu Province [M]. Beijing: Chinese Agricultural Technology Press. 288-303. (in Chinese)[4]TANG Hui-jun, 1997. Research on the population carrying capacity of the land resources in the economic area of Zhujiang Delta[J]. Journal of Guangdong University of Technology.14(3): 44. (in Chinese)

  2. 14 CFR 25.1310 - Power source capacity and distribution.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Power source capacity and distribution. 25... supply. The power sources and the system must be able to supply the following power loads in probable... source of power is required, after any failure or malfunction in any one power supply system...

  3. Effect of Shear Resistance on Flexural Debonding Load-Carrying Capacity of RC Beams Strengthened with Externally Bonded FRP Composites

    Directory of Open Access Journals (Sweden)

    Guibing Li

    2014-05-01

    Full Text Available Debonding failure is the main failure mode in flexurally strengthened reinforced concrete beams by externally bonded or near surface mounted fibre reinforced polymer (FRP composites. It is believed that FRP debonding will be initiated if the shear stress on the concrete-FRP interface reaches the tensile strength of concrete. However, it was found through experimental and analytical studies that the debonding mechanism of FRP composites has the potential of shear failure in combination with debonding failure. Moreover, the shear failure probably influences the debonding failure. Presently, there are very little experimental and analytical studies to investigate the influence of shear resistance of reinforced concrete (RC beam on FRP debonding failure. The current study investigates and analyzes the effect of shear resistance on FRP debonding failure based on test results. The analytical results show that the shear resistance of RC beam has a great effect on flexural debonding load-carrying capacity of FRP-strengthened RC beam. The influence of shear resistance on flexural debonding load-carrying capacity must be fully considered in flexural strengthening design of RC beams.

  4. Effects of design parameters on carrying capacity of a double-row tapered roller slewing bearing used in wind turbine

    Directory of Open Access Journals (Sweden)

    Yunfeng Li

    2016-07-01

    Full Text Available Mechanical model with detailed design parameters of a rotor slewing bearing with the structure type of double-row tapered roller for supporting the rotor of the wind turbine was presented. The internal geometrical relationships of the rotor slewing bearing were established in the Cartesian coordinate system. The elastic contact deformations between each tapered roller and the raceways were expressed through the geometrical transformation. The mechanical model was established using the equilibrium relations in the rotor slewing bearing. The safety factor and the fatigue life which represents, respectively, the ability of resisting the rolling contact plastic deformation failure and the rolling contact fatigue failure of the rotor slewing bearing were obtained based on the solution of the mechanical model. Effects of the detailed design parameters such as axial clearance, contact angle, and roller semi-cone angle on the carrying capacity of the rotor slewing bearing were analyzed. The results show that right amount of small negative axial clearance, increase in contact angle, and decrease in roller semi-cone angle are advantageous for enhancing the carrying capacity of the rotor slewing bearing. This provides the basis for the reasonable value selection of the design parameters of the double-row tapered roller slewing bearing for supporting the rotor of the wind turbine.

  5. Evaluation of resources and environment carrying capacity and socio-economic pressure in typical ecological regions, China

    Science.gov (United States)

    Qiusen, Huang; Xinyi, Xu

    2017-04-01

    Since the reform and opening up, the socio-economic pressures have led to increasingly tight resource constraints and serious environmental pollution problems in China, especially for typical ecological regions. The ecological system is under a severe situation and resource and environmental issues have become the bottleneck of economic development. Taking the Chen Barag Banner which has been considered as typical ecological regions as an example, the evaluation indexes system of resources and environment carrying capacity was divided into three subsystems: natural driving force, socio-economic pressure and ecological health. On the basis of the indexes system and related data of Chen Barag Banner in 2014, the evaluation model of resources and environment carrying capacity based on spring model were proposed to analysis the state of resources and environment carrying, and an assessment of influence of socio-economic pressure on the resources and environment system has been conducted by using the discretization method of socio-economic data. The results showed that:(1) The resources and environment system of Baorixile Town, Huhenuoer Town and Bayankuren Town were overloaded among the ten towns, the values of Resources and Environment Carrying Capacity(RECC) / Resources and Environment Carrying State(RECS) were 9.86, 1.37 and 1.22, respectively;(2) The natural driving force index of Xiwuzhuer Town, Hadatu state-owned farm and Bayanhada Town were 0.40, 0.42 and 0.43, respectively, which were lower than others and indicated that the natural conditions in these areas were better than others;(3) The situation of ecological environment Ewenke Town, Hadatu state-owned farm and Tenihe state-owned farm were the best due to the result that the ecological health index of these three towns were 0.21, 0.22 and 0.26, respectively, which were lower than others;(4) The influence of socio-economic pressure on the system of resources and environment in Baorixile Town, Hadatu state

  6. Competitive capacity of HIV-1 strains carrying M184I or Y181I drug-resistant mutations

    Institute of Scientific and Technical Information of China (English)

    LI Jue; LI Lin; LI Han-ping; ZHUANG Dao-min; LIU Si-yang; LIU Yong-jian; BAO Zuo-yi; WANG Zheng; LI Jing-yun

    2009-01-01

    Background Virus with nucleoside reverse transcriptase inhibitors (NRTIs) or nonnucleoside reverse transcdptase inhibitors (NNRTIs) resistant mutations show different evolution tendencies when the anti-viral therapies are interrupted. Understanding the replication fitness of drug-resistant virus is important for the study of the prevalence of drug-resistance. For this purpose, we characterized the replication capacity of HIV-1 virus carrying lamivudine (3TC) or nevirapine (NVP) resistant mutations.Methods 3TC and NVP resistant variants were induced in vitro by selecting wild type virus in the presence of drugs. For the competitive replication assay, drug-resistant variants were cocultured with wild-type virus in the presence or absence of drugs. The ratios of the viral species were determined over time by using a real-time RT-PCR-based assay. Results 3TC-resistant (M184I mutation) and NVP-resistant (Y181I mutation) virus should be selected in vitro in two different ways. The competitive replication assay showed that the ratio of virus carrying a M184I mutation increased from 98.8%, while the wild type virus decreased to 1.2% after 4 passages in the presence of 3TC; the percentage of virus carrying the Y181I mutation increased to 90.5%, while wild type virus decreased to 9.5% in the presence of NVP. In the absence of drugs, the ratio of virus carrying the M184I mutation decreased to 5.3%, while wild type virus increased to 94.7%; the ratio of virus carrying Y181I increased to 75%, while wild type virus decreased to 25% after 4 passages.Conclusions The NVP-resistant virus is fitter than wild type virus even in the absence of NVP that may be the reason that NNRTIs-resistant virus is spreading quickly.

  7. Assessing Potential Habitat and Carrying Capacity for Reintroduction of Plains Bison (Bison bison bison in Banff National Park.

    Directory of Open Access Journals (Sweden)

    Robin Steenweg

    Full Text Available Interest in bison (Bison bison, B. bonasus conservation and restoration continues to grow globally. In Canada, plains bison (B. b. bison are threatened, occupying less than 0.5% of their former range. The largest threat to their recovery is the lack of habitat in which they are considered compatible with current land uses. Fences and direct management make range expansion by most bison impossible. Reintroduction of bison into previously occupied areas that remain suitable, therefore, is critical for bison recovery in North America. Banff National Park is recognized as historical range of plains bison and has been identified as a potential site for reintroduction of a wild population. To evaluate habitat quality and assess if there is sufficient habitat for a breeding population, we developed a Habitat Suitability Index (HSI model for the proposed reintroduction and surrounding areas in Banff National Park (Banff. We then synthesize previous studies on habitat relationships, forage availability, bison energetics and snowfall scenarios to estimate nutritional carrying capacity. Considering constraints on nutritional carrying capacity, the most realistic scenario that we evaluated resulted in an estimated maximum bison density of 0.48 bison/km2. This corresponds to sufficient habitat to support at least 600 to 1000 plains bison, which could be one of the largest 10 plains bison populations in North America. Within Banff, there is spatial variation in predicted bison habitat suitability and population size that suggests one potential reintroduction site as the most likely to be successful from a habitat perspective. The successful reintroduction of bison into Banff would represent a significant global step towards conserving this iconic species, and our approach provides a useful template for evaluating potential habitat for other endangered species reintroductions into their former range.

  8. Assessing Potential Habitat and Carrying Capacity for Reintroduction of Plains Bison (Bison bison bison) in Banff National Park.

    Science.gov (United States)

    Steenweg, Robin; Hebblewhite, Mark; Gummer, David; Low, Brian; Hunt, Bill

    2016-01-01

    Interest in bison (Bison bison, B. bonasus) conservation and restoration continues to grow globally. In Canada, plains bison (B. b. bison) are threatened, occupying less than 0.5% of their former range. The largest threat to their recovery is the lack of habitat in which they are considered compatible with current land uses. Fences and direct management make range expansion by most bison impossible. Reintroduction of bison into previously occupied areas that remain suitable, therefore, is critical for bison recovery in North America. Banff National Park is recognized as historical range of plains bison and has been identified as a potential site for reintroduction of a wild population. To evaluate habitat quality and assess if there is sufficient habitat for a breeding population, we developed a Habitat Suitability Index (HSI) model for the proposed reintroduction and surrounding areas in Banff National Park (Banff). We then synthesize previous studies on habitat relationships, forage availability, bison energetics and snowfall scenarios to estimate nutritional carrying capacity. Considering constraints on nutritional carrying capacity, the most realistic scenario that we evaluated resulted in an estimated maximum bison density of 0.48 bison/km2. This corresponds to sufficient habitat to support at least 600 to 1000 plains bison, which could be one of the largest 10 plains bison populations in North America. Within Banff, there is spatial variation in predicted bison habitat suitability and population size that suggests one potential reintroduction site as the most likely to be successful from a habitat perspective. The successful reintroduction of bison into Banff would represent a significant global step towards conserving this iconic species, and our approach provides a useful template for evaluating potential habitat for other endangered species reintroductions into their former range.

  9. Meta-analysis of intrinsic rates of increase and carrying capacity of populations affected by toxic and other stressors.

    Science.gov (United States)

    Hendriks, A Jan; Maas-Diepeveen, Johanna L M; Heugens, Evelyn H W; Van Straalen, Nico M

    2005-09-01

    Most of the thousands of substances and species that are of concern for environmental management will not be investigated empirically at ecologically relevant levels because of financial, practical, and ethical constraints. To allow risk assessment for these less well-known categories, we have developed a mechanistic model with classical equations from toxicology and ecology. The parameters are linked to well-known properties, such as the octanol-water partition ratio K(ow), acute lethal (body) concentrations, and organism size. This allows estimation of intrinsic rates of increase r and carrying capacity K over a wide range of substances and species. The model was calibrated with parameter values (micro +/- 95% confidence interval) obtained in reviews and validated by a meta-analysis with largely independent data from 200 laboratory experiments. For single substances, the 5 to 95% interval of the observations on intrinsic rates of increase overlapped with the range predicted by the model. Model and experiments independently indicated that population growth ceased below 1% of the acute median lethal concentration in about 5% of the cases. Exceptional values and possible explanations were identified. The reduction of the carrying capacity K was nearly proportional to the inhibition of the population growth r. Population-level effects of mixtures as estimated by concentration addition were confirmed by observations in the experiments. The impact of a toxicant and another stressor could generally be described by response multiplication, with the exception of cases with extreme stress. Data sets on population laboratory experiments are biased to metals and crustaceans. This field will benefit from empirical studies on chemicals, conditions, and species, identified as risky by the model. Other implications of the model for environmental management and research are discussed.

  10. Browsing preference and ecological carrying capacity of sambar deer (Cervus unicolor brookei) on secondary vegetation in forest plantation.

    Science.gov (United States)

    Ismail, Dahlan; Jiwan, Dawend

    2015-02-01

    The browsing preference and ecological carrying capacity (ECC) of sambar deer (Cervus unicolor brookei) in acacia plantations for management and conservation of the ecosystem were investigated at Sabal Forest Reserve in Sarawak, Malaysia. The identification of the species browsed by the sambar deer was based on an observation of the plant parts consumed. ECC estimation was based on body weight (BW) and the physiological stages of animals browsed in six fenced 4-ha paddocks. Sambar deer were found foraging on only 29 out of 42 species of secondary vegetation in the acacia plantation. The remaining species are too high for the deer to reach. Planted species, Shorea macrophylla are not palatable to the deer. This augurs well for the integration of sambar deer into shorea plantations. The most frequently exploited plants were Ficus spp. Sambar deer preferred woody species more than non-woody species and they are browser animals. By producing metabolizable energy of 19,000 to 27,000 MJ/ha, the ECC was five head/ha to 5.25 head/ha. Given its contribution to the conservation of wildlife and its capacity to sustain the ecosystem, the sambar deer integrated farming system offers a promising strategy for the future of tropical forestry management.

  11. A new numerical method for determining collapse load-carrying capacity of structure made of elasto-plastic material

    Institute of Scientific and Technical Information of China (English)

    钟志鹏; 任大龙; 万水

    2014-01-01

    Determination of collapse load-carrying capacity of elasto-plastic material is very important in designing structure. The problem is commonly solved by elasto-plastic finite element method (FEM). In order to deal with material nonlinear problem involving strain softening problem effectively, a new numerical method-damped Newton method was proposed. The iterative schemes are discussed in detail for pure equilibrium models. In the equilibrium model, the plasticity criterion and the compatibility of the strains are verified, and the strain increment and plastic factor are treated as independent unknowns. To avoid the stiffness matrix being singularity or condition of matrix being ill, a damping factor α was introduced to adjust the value of plastic consistent parameter automatically during the iterations. According to the algorithm, the nonlinear finite element program was complied and its numerical example was calculated. The numerical results indicate that this method converges very fast for both small load steps and large load steps. Compared with those results obtained by analysis and experiment, the predicted ultimate bearing capacity from the proposed method is identical.

  12. Grid Integration and the Carrying Capacity of the U.S. Grid to Incorporate Variable Renewable Energy

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, Jaquelin [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Denholm, Paul [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Speer, Bethany [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Miller, Mackay [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-04-23

    In the United States and elsewhere, renewable energy (RE) generation supplies an increasingly large percentage of annual demand, including nine U.S. states where wind comprised over 10% of in-state generation in 2013. This white paper summarizes the challenges to integrating increasing amounts of variable RE, identifies emerging practices in power system planning and operation that can facilitate grid integration, and proposes a unifying concept—economic carrying capacity—that can provide a framework for evaluating actions to accommodate higher penetrations of RE. There is growing recognition that while technical challenges to variable RE integration are real, they can generally be addressed via a variety of solutions that vary in implementation cost. As a result, limits to RE penetration are primarily economic, driven by factors that include transmission and the flexibility of the power grid to balance supply and demand. This limit can be expressed as economic carrying capacity, or the point at which variable RE is no longer economically competitive or desirable to the system or society.

  13. 巫山县生态承载力研究%STUDY ON THE ECOLOGICAL CARRYING CAPACITY IN WUSHAN COUNTY

    Institute of Scientific and Technical Information of China (English)

    吴晓; 吴宜进

    2013-01-01

    Land resources are the carrier of all resources and environmental factors,which has played an extremely important role in the socio-economic operation.Wushan County is mainly mountainous,the land resources are very barren,the arable land which mostly is sloping land has a poor quality,and the soil erosion is much more serious than other areas.Due to the construction of the Three Gorges Project,a large number of immigrants need to build their new home in place.The pressure which is carried by land is surging.All of the above has hindered the sustainable socio-economic development in Wushan County.In recent years,scholars note that the rational utilization of land resources in Wushan County has a crucial importance on sustainable development and the coordinated development of the human-land relationship in Wushan County.Because of this,the scholars have conducted a preliminary study and have published a number of papers.The number of the research papers which is mainly about ecological footprint of the county scale accounts for 7.83% of the total number of papers of the ecological footprint.The quantity of the papers is very poor and the number of the results of original research is very small.In the process of quantitative analysis of the land carrying capacity in Wushan County,the paper referred to the results of previous studies,and used ecological footprint model to analyze the land carrying capacity in Wushan County from 2005 to 2010,to provide a basis and reference for the ecological building and sustainable development in Wushan County.In this paper,the land of ecological carrying capacity of Wushan County from 2005 to 2010 was analyzed by using the principles and models of the ecological footprint.According to the principles and models of the ecological footprint,this paper calculated the ecological footprint from 2005 to 2010 in Wushan County,the ecological carrying capacity in 2005 and 2010 in Wushan County,and the ecological footprints of production per

  14. Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists' Spatial Behavior Simulator Based on GIS and Multi-Agent System

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ren-jun

    2005-01-01

    Based on the study of visitors' individual spatial behaviors, a tourists' spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed, TSBS employs GIS (Geographic Information System) to manage the spatial data, and Multi-Agent system to simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such as location, cost, and state can be analyzed and predicted. Based on this analysis and prediction, the model of assessing the carrying capacity of resorts is built. Our results show that TSBS will be an effective tool to accurately assess the carrying capacity of tourist resorts.

  15. EFFECT OF GROWTH STAGES AND RANGE SYSTEMS ON VEGETATION ATTRIBUTES, CARRYING CAPACITY, STOCKING RATE AND FORAGE PRODUCTIVITY, NORTH KORDOFAN, SUDAN

    Directory of Open Access Journals (Sweden)

    Abdel Moniem M.A. El hag

    2012-03-01

    Full Text Available The range vegetation attributes, carrying capacity, stocking rates and forage productivity were studied in close and open range systems at the flowering and seed setting stages during the September and November 2010, respectively, in El Rosa (El-khuwei locality. Sampling was done by locating 2Km2 in close and open range systems in a radiating manner from the centre of each site. Completely Randomized Design (CRD was used to analyses treatments. Biomass production of plants and plant cover at the flowering stage in the close range system were significantly (P<0.0001 higher than that at the seed setting stage in the open range system. The plant density was significant (P<0.05 higher in the close rang system at the flowering stage and lower at the seed setting stage in the open range system. Bare soil and litter was significantly higher (P<0.0001 in the open range system during the seed setting stage and lower in the close range system during the flowering stage. Forage productivity of plants and shrubs browse kg/ha on rangeland was significantly higher (P<0.05 in the close range system during the flowering stage and lower in open range system at the seed setting stage. Carrying capacity was significantly higher (P<0.0001 in the close range system at the seed setting stage and lower in the open range at the flowering stage. Stoking rates in open range system during the seed setting stage was significantly higher (P<0.0001 and lower in the close range system during the seed setting stage. The frequencies of Huskneet (Cenchrus biflorus, Bano, (Eragrostis tremula, Difra (Echinocloa colonum, leflef Luffa aegyptiaca, Gaw (Aristida sp, Shuleny Zornia glochidiata and Aborakhus Andropogon gayanus were higher in close system during the two stages of growth. Plants such as Abodaib Ceraotheca sesamoid, Bigual Blepharis linarifolia, Tmrfar (Oldenlandia senegalensis, Rabaa (Zalea sp, Himeira Hymerocardia, Diresa (Tribulus terrestris and Huntot Merremia pinnata

  16. 基于物元分析理论的旅游承载力研究%Study on Tourist Carrying Capacity Based on Matter Element Analysis

    Institute of Scientific and Technical Information of China (English)

    刘云国

    2005-01-01

    This paper proposes that it is necessary to implement the concept of tourist carrying capacity to facilitate the tourism planning, and presents a method to evaluate the carrying capacity. The method cailed matter element analysis can solve the uncertain a,nd incompatible problem of the evaluated factors in assessing carrying capacity.The current state of a destination s carrying capacity can be determined by establishing the standard indexes and the matter element model. Through the evaluating of the travel industry zones of the Autonomous Prefecture of Western Hunan, the method is proved to be simple and feasible, and it is improved to be significant for the tourism planning and determination as well as the sustainable development of the regional tourism.

  17. 桑沟湾养殖容量与优化措施的研究%Carrying capacity and optimizing measures for mariculture in Sungo Bay

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The carrying capacity of Sungo Bay for the culture of scallop Chlamys farreri was estimated by calculating the supply and demand of organic carbon produced by primary production.The carrying capacity for the large scallops (5~6 cm shell height) is about 35 ind./m2,which is 15 ind./m2 lower than the actual cultivating density.By calculating the total supply and demand of inorganic nutrient,the carrying capacity of the bay for kelp Laminaria japanica was estimated for the first time in the world.Based on the results from assessment of carrying capacity,some optimizing measures such as polyculture of bivalves and kelp,controlling fouling organisms,adjusting the size of longline block,enlarging the navigation channel and so on were proposed and practiced in the bay.

  18. A Comparative Analysis on Assessment of Land Carrying Capacity with Ecological Footprint Analysis and Index System Method.

    Science.gov (United States)

    Qian, Yao; Tang, Lina; Qiu, Quanyi; Xu, Tong; Liao, Jiangfu

    2015-01-01

    Land carrying capacity (LCC) explains whether the local land resources are effectively used to support economic activities and/or human population. LCC can be evaluated commonly with two approaches, namely ecological footprint analysis (EFA) and the index system method (ISM). EFA is helpful to investigate the effects of different land categories whereas ISM can be used to evaluate the contributions of social, environmental, and economic factors. Here we compared the two LCC-evaluation approaches with data collected from Xiamen City, a typical region where rapid economic growth and urbanization are found in China. The results show that LCC assessments with EFA and ISM not only complement each other but also are mutually supportive. Both assessments suggest that decreases in arable land and increasingly high energy consumption have major negative effects on LCC and threaten sustainable development for Xiamen City. It is important for the local policy makers, planners and designers to reduce ecological deficits by controlling fossil energy consumption, protecting arable land and forest land from converting into other land types, and slowing down the speed of urbanization, and to promote sustainability by controlling rural-to-urban immigration, increasing hazard-free treatment rate of household garbage, and raising energy consumption per unit industrial added value. Although EFA seems more appropriate for estimating LCC for a resource-output or self-sufficient region and ISM is more suitable for a resource-input region, both approaches should be employed when perform LCC assessment in any places around the world.

  19. Hypoxia effects on gill surface area and blood oxygen-carrying capacity of the Atlantic stingray, Dasyatis sabina.

    Science.gov (United States)

    Dabruzzi, Theresa F; Bennett, Wayne A

    2014-08-01

    Atlantic stingrays, Dasyatis sabina, are common residents of shallow-water seagrass habitats that experience natural cycles of severe hypoxia during summer months. We hypothesized that stingrays exposed to hypoxic episodes would improve their hypoxia tolerance by increasing branchial surface area and altering blood oxygen-carrying capacity. To this end, we compared critical oxygen minimum, gill morphology, and hemoglobin/hematocrit levels in a control group of Atlantic stingrays held at continuous oxygen saturations of 80-90% (≥5.5 mg/l), to treatment groups exposed to a 7-h hypoxic interval at 55% (~4.0 mg/l), or 30% oxygen saturation (~2.0 mg/l). Stingrays in hypoxic treatment groups significantly improved their hypoxia tolerance. Critical oxygen minimum values fell from 0.7 ± 0.11 mg/l in control fish to 0.4 ± 0.05 and 0.4 ± 0.06 mg/l in the 55 and 30% saturation treatment groups, respectively. Mass-specific gill surface area between control fish and the 30% saturation treatment group increased by 1.7-fold, from 85 to 142 mm(2)/g. Although stingrays did not show an increase in hematocrit or hemoglobin levels, production of more efficient hemoglobin isoforms could not be ruled out. An increase in hypoxia tolerance allows Atlantic stingrays to forage for longer times and across a wide range of hypoxic habitats that are less accessible to predators and competitors.

  20. A Comparative Analysis on Assessment of Land Carrying Capacity with Ecological Footprint Analysis and Index System Method.

    Directory of Open Access Journals (Sweden)

    Yao Qian

    Full Text Available Land carrying capacity (LCC explains whether the local land resources are effectively used to support economic activities and/or human population. LCC can be evaluated commonly with two approaches, namely ecological footprint analysis (EFA and the index system method (ISM. EFA is helpful to investigate the effects of different land categories whereas ISM can be used to evaluate the contributions of social, environmental, and economic factors. Here we compared the two LCC-evaluation approaches with data collected from Xiamen City, a typical region where rapid economic growth and urbanization are found in China. The results show that LCC assessments with EFA and ISM not only complement each other but also are mutually supportive. Both assessments suggest that decreases in arable land and increasingly high energy consumption have major negative effects on LCC and threaten sustainable development for Xiamen City. It is important for the local policy makers, planners and designers to reduce ecological deficits by controlling fossil energy consumption, protecting arable land and forest land from converting into other land types, and slowing down the speed of urbanization, and to promote sustainability by controlling rural-to-urban immigration, increasing hazard-free treatment rate of household garbage, and raising energy consumption per unit industrial added value. Although EFA seems more appropriate for estimating LCC for a resource-output or self-sufficient region and ISM is more suitable for a resource-input region, both approaches should be employed when perform LCC assessment in any places around the world.

  1. Carbon carry capacity and carbon sequestration potential in China based on an integrated analysis of mature forest biomass.

    Science.gov (United States)

    Liu, YingChun; Yu, GuiRui; Wang, QiuFeng; Zhang, YangJian; Xu, ZeHong

    2014-12-01

    Forests play an important role in acting as a carbon sink of terrestrial ecosystem. Although global forests have huge carbon carrying capacity (CCC) and carbon sequestration potential (CSP), there were few quantification reports on Chinese forests. We collected and compiled a forest biomass dataset of China, a total of 5841 sites, based on forest inventory and literature search results. From the dataset we extracted 338 sites with forests aged over 80 years, a threshold for defining mature forest, to establish the mature forest biomass dataset. After analyzing the spatial pattern of the carbon density of Chinese mature forests and its controlling factors, we used carbon density of mature forests as the reference level, and conservatively estimated the CCC of the forests in China by interpolation methods of Regression Kriging, Inverse Distance Weighted and Partial Thin Plate Smoothing Spline. Combining with the sixth National Forest Resources Inventory, we also estimated the forest CSP. The results revealed positive relationships between carbon density of mature forests and temperature, precipitation and stand age, and the horizontal and elevational patterns of carbon density of mature forests can be well predicted by temperature and precipitation. The total CCC and CSP of the existing forests are 19.87 and 13.86 Pg C, respectively. Subtropical forests would have more CCC and CSP than other biomes. Consequently, relying on forests to uptake carbon by decreasing disturbance on forests would be an alternative approach for mitigating greenhouse gas concentration effects besides afforestation and reforestation.

  2. A New Methodology for Solving Trajectory Planning and Dynamic Load-Carrying Capacity of a Robot Manipulator

    Directory of Open Access Journals (Sweden)

    Wanjin Guo

    2016-01-01

    Full Text Available A new methodology using a direct method for obtaining the best found trajectory planning and maximum dynamic load-carrying capacity (DLCC is presented for a 5-degree of freedom (DOF hybrid robot manipulator. A nonlinear constrained multiobjective optimization problem is formulated with four objective functions, namely, travel time, total energy involved in the motion, joint jerks, and joint acceleration. The vector of decision variables is defined by the sequence of the time-interval lengths associated with each two consecutive via-points on the desired trajectory of the 5-DOF robot generalized coordinates. Then this vector of decision variables is computed in order to minimize the cost function (which is the weighted sum of these four objective functions subject to constraints on joint positions, velocities, acceleration, jerks, forces/torques, and payload mass. Two separate approaches are proposed to deal with the trajectory planning problem and the maximum DLCC calculation for the 5-DOF robot manipulator using an evolutionary optimization technique. The adopted evolutionary algorithm is the elitist nondominated sorting genetic algorithm (NSGA-II. A numerical application is performed for obtaining best found solutions of trajectory planning and maximum DLCC calculation for the 5-DOF hybrid robot manipulator.

  3. Carrying capacity and tourism planning. case study at Praia Brava- Itajai, in face to the settlement of Canto da Brava Resort

    OpenAIRE

    Doris Van de Meene Ruschmann; Luciana Paolucci; Nelson Antonio Leite Maciel

    2008-01-01

    Sustainable tourism presumes cultural authenticity, social inclusion, conservation of natural resources and service quality. Those are major issues standing for economical viability in the long run. This article analyzes carrying capacity in Praia Brava, Itajai/SC, evaluating environmental comfort for dwellers as well as for users of the beach building future scenarios as Canto da Brava resort is settled. Tourism carrying capacity is tied to methods of identification and evaluation of environ...

  4. An integrated approach for assessing aquatic ecological carrying capacity: a case study of Wujin District in the Tai Lake Basin, China.

    Science.gov (United States)

    Zeng, Chen; Liu, Yaolin; Liu, Yanfang; Hu, Jiameng; Bai, Xiaogang; Yang, Xiaoyu

    2011-01-01

    Aquatic ecological carrying capacity is an effective method for analyzing sustainable development in regional water management. In this paper, an integrated approach is employed for assessing the aquatic ecological carrying capacity of Wujin District in the Tai Lake Basin, China. An indicator system is established considering social and economic development as well as ecological resilience perspectives. While calculating the ecological index, the normalized difference vegetation index (NDVI) is extracted from Moderate Resolution Imaging Spectroradiometer (MODIS) time-series images, followed by spatial and temporal analysis of vegetation cover. Finally, multi-index assessment of aquatic ecological carrying capacity is carried out for the period 2000 to 2008, including both static and dynamic variables. The results reveal that aquatic ecological carrying capacity presents a slight upward trend in the past decade and the intensity of human activities still exceeded the aquatic ecological carrying capacity in 2008. In terms of human activities, population has decreased, GDP has quadrupled, and fertilizer application and industrial wastewater discharge have declined greatly in the past decade. The indicators representing aquatic ecosystem conditions have the lowest scores, which are primarily attributed to the water eutrophication problem. Yet the terrestrial ecosystem is assessed to be in better condition since topographic backgrounds and landscape diversity are at higher levels. Based on the work carried out, it is suggested that pollutant emission be controlled to improve water quality and agricultural development around Ge Lake (the largest lake in Wujin District) be reduced.

  5. Research on atmospheric environment carrying capacity of ports%港口大气环境承载力研究

    Institute of Scientific and Technical Information of China (English)

    刘长兵

    2012-01-01

    以秦皇岛煤炭港口为例,筛选煤粉尘(TSP)作为典型大宗散货港口大气环境优先污染物,通过对港口区域现有重点煤尘污染源、烟尘污染源和工业粉尘污染源排放和治理状况以及大气污染物迁移扩散规律的研究,结合社会、经济和环境因素,以满足秦皇岛煤炭作业环境和周边地区大气环境功能区环境质量标准为约束条件,探求了港口大气污染物排放总量及环境承载力控制目标.%In this paper,taking Qinhuangdao coal port for example,TSP was selected as the priority pollutants of atmospheric environment of the typical large-sized bulk cargo port.The emission and treatment of the existing key pollution sources for coal dust smoke and dust, industrial dust and the spreading law of air pollutants in port area were studied.Under the constraint conditions of coal working environment of Qinhuangdao and the atmospheric environment functional regionalization environmental quality standard of its surrounding areas,the control targets of the total air pollutants emission and the environment carrying capacity of port were explored with the combination of the social,economic and environmental factors.These results can provide effective technical support for the general development plan of port,dust pollution treatment and environmental feasibility study of a new port.

  6. 楼观台森林公园旅游环境容量研究%Tourism Environmental Carrying Capacity of Louguantai Forest Park

    Institute of Scientific and Technical Information of China (English)

    张晓慧; 陈强

    2011-01-01

    综合旅游空间容量、旅游生态容量、旅游设施容量、旅游心理容量4个因素,对楼观台国家森林公园旅游环境容量进行了测算,通过对比发现楼观台森林公园游客接待量远小于理论旅游环境容量,并对造成这种现状的主要原因进行了分析,提出了相关建议.%In this paper, an integrated estimation on the tourism environmental carrying capacity of Louguantai National Forest Park was made from the aspects of ecological carrying capacity, spatial carrying capacity, facility carrying capacity, and psychological carrying capacity. It was found that the number of reception tourists in the park was far less than its theoretical predication tourism environment capacity. Main reasons were analysised and some suggestions were proposed.

  7. Evaluation of Carrying Capacity : Measure 7.1A of the Northwest Power Planning Council`s 1994 Fish and Wildlife Program : Report 1 of 4, Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Neitzel, Duane A.; Johnson, Gary E.

    1996-05-01

    This report is one of four that the Pacific Northwest National Laboratory (PNNL) staff prepared to address Measure 7.1A in the Northwest Power Planning Council's (Council) Fish and Wildlife Program (Program) dated december 1994 (NPPC 1994). Measure 7.1A calls for the Bonneville Power Administration (BPA) to fund an evaluation of salmon survival, ecology, carrying capacity, and limiting factors in freshwater, estuarine, and marine habitats. Additionally, the Measure asks for development of a study plan based on critical uncertainties and research needs identified during the evaluation. This report deals with the evaluation of carrying capacity. It describes the analysis of different views of capacity as it relates to salmon survival and abundance. The report ends with conclusions and recommendations for studying carrying capacity.

  8. Spatial partitioning between species of the phytoplankton-feeding guild on an estuarine intertidal sand flat and its implication on habitat carrying capacity

    Science.gov (United States)

    Tamaki, Akio; Nakaoka, Ayumi; Maekawa, Hideki; Yamada, Fumihiko

    2008-07-01

    The fishery yield of Manila clams, Ruditapes philippinarum, increased considerably in the 1970s but has decreased rapidly since the middle 1980s on extensive intertidal sand flats in Ariake Sound (Kyushu, Japan). A survey conducted in 2004 on a 3.4-km 2 sand flat located in the central part of the Sound (Shirakawa sand flat) revealed four dominant species: two thalassinidean shrimps ( Upogebia major and Nihonotrypaea japonica), which are deep-reaching burrow dwellers with strong bioturbation activities, and two bivalves ( Mactra veneriformis and R. philippinarum). All four species belong to a phytoplankton (diatom)-feeding guild. In the late 1970s, the Manila clam population prevailed in high densities over the entire sand flat, whereas its distribution was restricted to the lowest quarter of the shore in 2004. In contrast, the population sizes and zones of occurrence of the other phytoplankton feeders have expanded in the absence of R. philippinarum, perhaps an indication of competitive release. After establishment, effects of the thalassinidean shrimps on sediment stability appear to have further reduced clam abundances. Across the sand flat in 2004, wet weight population biomass estimates for N. japonica, U. major, M. veneriformis, and R. philippinarum (whole body for shrimps and soft tissue for bivalves) were 304, 111, 378, and 234 tonnes, respectively. Based on Manila clam fishery yield records from Shirakawa, the carrying capacity of the Shirakawa sand flat in the late 1970s was estimated to be two times greater than the sum value for the whole phytoplankton-feeding guild in 2004. It is hypothesized that (1) the amount of phytoplankton determines the carrying capacity for the benthic community on the Shirakawa sand flat, with both phytoplankton and benthic biomass at maxima in the late 1970s, and (2) the subsequent increases in competition for space have caused further declines in the Manila clam population biomass to approximately one-eighth of its past

  9. High-capacity quantum Fibonacci coding for key distribution

    Science.gov (United States)

    Simon, David S.; Lawrence, Nate; Trevino, Jacob; Dal Negro, Luca; Sergienko, Alexander V.

    2013-03-01

    Quantum cryptography and quantum key distribution (QKD) have been the most successful applications of quantum information processing, highlighting the unique capability of quantum mechanics, through the no-cloning theorem, to securely share encryption keys between two parties. Here, we present an approach to high-capacity, high-efficiency QKD by exploiting cross-disciplinary ideas from quantum information theory and the theory of light scattering of aperiodic photonic media. We propose a unique type of entangled-photon source, as well as a physical mechanism for efficiently sharing keys. The key-sharing protocol combines entanglement with the mathematical properties of a recursive sequence to allow a realization of the physical conditions necessary for implementation of the no-cloning principle for QKD, while the source produces entangled photons whose orbital angular momenta (OAM) are in a superposition of Fibonacci numbers. The source is used to implement a particular physical realization of the protocol by randomly encoding the Fibonacci sequence onto entangled OAM states, allowing secure generation of long keys from few photons. Unlike in polarization-based protocols, reference frame alignment is unnecessary, while the required experimental setup is simpler than other OAM-based protocols capable of achieving the same capacity and its complexity grows less rapidly with increasing range of OAM used.

  10. Carrying capacity and tourism planning. case study at Praia Brava- Itajai, in face to the settlement of Canto da Brava Resort

    Directory of Open Access Journals (Sweden)

    Doris Van de Meene Ruschmann

    2008-05-01

    Full Text Available Sustainable tourism presumes cultural authenticity, social inclusion, conservation of natural resources and service quality. Those are major issues standing for economical viability in the long run. This article analyzes carrying capacity in Praia Brava, Itajai/SC, evaluating environmental comfort for dwellers as well as for users of the beach building future scenarios as Canto da Brava resort is settled. Tourism carrying capacity is tied to methods of identification and evaluation of environmental indicators. In this case, Cifuentes Method was chosen because it integrates physical, biotical and infra structural factors, through assessment of physical, real and effective carrying capacity. Quantitative results have been considered analyzing impacts and tolerable limits of change taking into account users perception.

  11. A model to assess fundamental and realized carrying capacities of island ecosystem: A case study in the southern Miaodao Archipelago of China

    Institute of Scientific and Technical Information of China (English)

    SHI Honghua; SHEN Chengcheng; ZHENG Wei; LI Fen; WANG Xiaoli; CHI Yuan; GUO Zhen

    2016-01-01

    Research on carrying capacity, aiming at maintaining the limited ability of the Earth's life supporting system to sustain human development, requires a comprehensive and ecosystem-based approach to monitor and assess the localized sustainability of coupled social and ecological systems. A definition termed the ecosystem-based carrying capacity of island (EBCCI) was developed in this paper of which the indices of fundamental and realized carrying capacities of island (FCCI and RCCI) were highlighted to emphasize the inter-dependencies between social systems and ecological systems. In order to avoid the difficulties and uncertainties of direct assessment, the related assessment model was established on the basis of synthetic evaluation of inherent and external factors affecting the EBCCI. The southern Miaodao Archipelago (SMA) located in the intersection of the Bohai Sea and the Yellow Sea, China, was taken as a typical example to acquire integrated recognition of the island ecosystem and its carrying capacity so as to discuss its sustainable development. The index scores of FCCI and RCCI in the SMA were 0.818 5 and 0.712 9 out of 1.0, respectively, with acceptable uncertainties. The results showed a relatively well capacity to sustain progress and relatively well realization of the carrying capacity of island ecosystem, owing to a well capacity of ecologically regulating, general performance of both ecologically supporting and resource provisioning, and a relatively high level of social supporting system. The study implied that it was critical to optimize the inter-dependencies and to sustain the relative balance between social systems and ecological systems so as to improve the RCCI and further facilitate the sustainability of SMA. The approach proposed in this paper provides a powerful tool which is well applicative to the regional level of an oceanic island or archipelago to study the sustainable development and can be further popularized to the coastal zone.

  12. 成都市水资源及水环境承载能力分析%Study on water resources and water environmental carrying capacities of Chengdu

    Institute of Scientific and Technical Information of China (English)

    薛小妮; 甘泓; 游进军; 牛存稳

    2012-01-01

    Based on the analyses made on the definitions of the water resources carrying capacity and water environmental carrying capacity and the significances of studies on them, both the carrying capacities of various target years of Chengdu are calculated herein with a three-level methodology and the one-dimension water quality simulation based pollutant-holding capacity model respectively, and then a comparative analysis is made on the calculation results. The result shows that the limitation from water environmental capacity on the water consumption of Chengdu becomes more strict under the current condition, while the water resources carrying capacity is to restrict the socio-economic development gradually in the days to come. Therefore, the sustainable economic and social development can only be ensured therein by taking both the carrying capacities as the control points concerned.%本文在分析水资源和水环境承载能力定义及研究意义的基础上,分别利用三层次分析方法和基于一维水质模拟的纳污能力模型计算了成都市不同水平年的水资源与水环境承载能力,并对计算结果进行对比分析.结果显示现状条件下成都市的水环境承载能力对用水的限制更为严格,而未来水资源承载能力逐渐开始制约社会经济发展.为此,只有以水资源承载能力及水环境承载能力作为控制点,才能保障经济社会的可持续发展.

  13. 人口承载力研究的演进、问题与展望%Research on Population Carrying Capacity: Evolution, Problems and Prospect

    Institute of Scientific and Technical Information of China (English)

    童玉芬

    2012-01-01

    There have long been debates and conflicting arguments in the studies of population cartying capacity. This paper examines dilemmas and challenges in the studies of population carrying capacity. There are three major difficulties in the research of population carrying capacity: difficulty in conducting quantitative models of population carrying capacity with empirical researches due to limitations in theoretical hypotheses, difficulty in accurately determining the results of population carrying capacity due to the changing nature and the complexity and uncertainty of the influencing factors of population carrying capacity, and difficulty in operationalizing policy measures deriving from the research on popu- lation carrying capacity. The author argues that population carrying capacity exists objectively, and scholars should not abandon their research just because of the difficulties and problems in the studies of population carrying capacity. There is a need in the research on population carrying capacity to disembarrass of that of biological carrying capacity. Studies on population carrying capacity need to be conducted in dynamic perspectives.%在人口承载力研究的过程中,始终伴随着对人口承载力的争论、质疑甚至否定。文章分析了人口承载力演变的过程和存在的困境及原因,认为目前的困难主要表现在:由于人口承载力研究理论假设的局限,从而导致了入口承载力的定量模型难以得到实证检验;人口承载力影响因素的动态性、不确定性和多样性,导致承载力结果难以精确测定;受到研究范式的局限,由概念的不精确和歧义导致了可操作性差。最后指出,人口承载力是客观存在的,不能因为人口承载力研究中存在的这些困难而作为放弃人口承载力研究的借口;人口承载力的研究,需要进一步摆脱生物承载力的研究模式,从一种固定不变的环境和不变的生活模式等

  14. Earth Resources Technology Satellite-1 (ERTS-1) data and anthropology: Use of these data in carrying capacity estimates for sites in Upper Volta and Niger

    Science.gov (United States)

    Reining, P. (Principal Investigator)

    1974-01-01

    The author has identified the following significant results. Repetitively derived multispectral band imagery from ERTS-1 is now available for many parts of the earth's land surface and represents major new data sources for anthropological work in habitat, land use, and settlement patterns. A completed first step test of ERTS-1 data is available in carrying capacity estimates for Mossi, Hausa, and Sonrai sites derived from: (1) field work; (2) aerial photography; and (3) ERTS-1. Data can test more than one carrying capacity formula.

  15. Effective carrying capacity and analytical solution of a particular case of the Richards-like two-species population dynamics model

    Science.gov (United States)

    Cabella, Brenno Caetano Troca; Ribeiro, Fabiano; Martinez, Alexandre Souto

    2012-02-01

    We consider a generalized two-species population dynamic model and analytically solve it for the amensalism and commensalism ecological interactions. These two-species models can be simplified to a one-species model with a time dependent extrinsic growth factor. With a one-species model with an effective carrying capacity one is able to retrieve the steady state solutions of the previous one-species model. The equivalence obtained between the effective carrying capacity and the extrinsic growth factor is complete only for a particular case, the Gompertz model. Here we unveil important aspects of sigmoid growth curves, which are relevant to growth processes and population dynamics.

  16. Carry a big stick, or no stick at all An experimental analysis of trust and capacity of punishment

    OpenAIRE

    Vicente Calabuig; Enrique Fatas; Gonzalo Olcina; Ismael Rodriguez-Lara

    2013-01-01

    We investigate the effect of punishment in a trust game with endowment heterogeneity in which the investor may punish the allocator at a cost. Our results indicate that the effect of the punishment crucially depends on the investor’s capacity of punishment, that is measured in our experiment by the proportion of the allocator’s payoffs that the investor can destroy. We find that punishment fosters trust when the capacity of punishment is high (i.e., when the cost of punishing is relatively lo...

  17. Distribution of available soil water capacity in China

    Institute of Scientific and Technical Information of China (English)

    ZHOUWenzuo; LIUGaohuan; PANJianjun; FENGXianfeng

    2005-01-01

    The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for most of soil profiles and the nationwide ASWC largely remains lacking in relevant soil data in China. This work was to estimate ASWC based on physical and chemical properties and analyze the spatial distribution of ASWC in China. The pedo-transfer functions (PTFs), derived from 220 survey data of ASWC, and the empirical data of ASWC based on soil texture were applied to quantify the ASWC. GIS technology was used to develop a spatial file of ASWC in China and the spatial distribution of ASWC was also analyzed. The results showed the value of ASWC ranges from 15×10-2 cm3·cm-3 to 22×10-2 cm3·cm-3 for most soil types, and few soil types are lower than 15×10-2 cm3·cm-3 or higher than 22×10-2 cm3·cm-3, The ASWC is different according to the complex soil types and their distribution, It is higher in the east than that in the west, and the values reduce from south to north except the northeastern part of China. The “high” values of ASWC appear in southeast, northeastern mountain regions and Northeast China Plain. The relatively “high” values of ASWC appear in Sichuan basin, Huang-Huai-Hai plain and the east of Inner Mongolia. The relatively “low” values are distributed in the west and the Loess Plateau of China. The “very low” value regions are the northern Tibetan Plateau and the desertified areas in northern China. In some regions, the ASWC changes according to the complex topography and different types of soils. Though there remains precision limitation, the spatial data of ASWC derived from this study are improved on current data files of soil water retention properties for Chinese soils. This study presents basic data and analysis methods for estimation and evaluation of ASWC in China.

  18. Analysis of the University of Ibadan Carrying Capacities vis-à-vis Enrolment and Facilities' Maintenance: Implications on Administration and Curriculum Implementation

    Science.gov (United States)

    Atanda, Ademola

    2013-01-01

    This study investigated the extent to which the University of Ibadan complies with carrying capacity standards as directed by the National Universities Commission (NUC) and the level of facility maintenance. A descriptive research design was adopted with three research questions. The population of study comprised undergraduate students and an…

  19. Potential for Grey wolf Canis lupus in the Netherlands : effects of habitat fragmentation and climate change on the carrying capacity and population dynamics

    NARCIS (Netherlands)

    Potiek, A.; Wamelink, G.W.W.; Jochem, R.; Langevelde, van F.

    2012-01-01

    Recolonization of the Netherlands by wolves is likely to occur within 5 to 10 years, and for management reasons the habitat suitability should be understood. Therefore, I predicted the carrying capacity and population dynamics of the wolf in the Netherlands, and studied the effects of habitat fragme

  20. Analysis of the University of Ibadan Carrying Capacities vis-à-vis Enrolment and Facilities' Maintenance: Implications on Administration and Curriculum Implementation

    Science.gov (United States)

    Atanda, Ademola

    2013-01-01

    This study investigated the extent to which the University of Ibadan complies with carrying capacity standards as directed by the National Universities Commission (NUC) and the level of facility maintenance. A descriptive research design was adopted with three research questions. The population of study comprised undergraduate students and an…

  1. Potential for Grey wolf Canis lupus in the Netherlands : effects of habitat fragmentation and climate change on the carrying capacity and population dynamics

    NARCIS (Netherlands)

    Potiek, A.; Wamelink, G.W.W.; Jochem, R.; Langevelde, van F.

    2012-01-01

    Recolonization of the Netherlands by wolves is likely to occur within 5 to 10 years, and for management reasons the habitat suitability should be understood. Therefore, I predicted the carrying capacity and population dynamics of the wolf in the Netherlands, and studied the effects of habitat

  2. Could the local population of the Lower Rhine delta supply the Roman army? Part 2: Modelling the carrying capacity using archaeological, palaeo-ecological and geomorphological data

    NARCIS (Netherlands)

    M. van Dinter; L.I. Kooistra; M.K. Dütting; P. van Rijn; C. Cavallo

    2014-01-01

    In this part two of a diptych of articles, we modelled and quantified the carrying capacity of the landscape and the demand and supply of the Roman army in the western Lower Rhine delta with wood and food in the period A.D. 40 - 140. The absolute volumes of the wood and food were calculated (in m³ a

  3. 区域环境承载力的定量化探讨--以大连市为例%Quantificational Study on Carrying Capacity of the Regional Environment -Taking the City of Dalian as an Example

    Institute of Scientific and Technical Information of China (English)

    狄乾斌

    2005-01-01

    With the analysis of the connotation and charter of the regional environment's carrying capacity, this paper,firstly, establishes the index system on the base of the affecting factors. Secondly, this paper discusses the methods of the quantization of the environment's carrying capacity of Dalian. Finally, this paper predicts the changing tendency of the environment's carrying capacity.

  4. Microbial organisms carried by brown-banded cockroaches in relation to their spatial distribution in a hospital.

    OpenAIRE

    Le Guyader, A.; Rivault, C.; Chaperon, J

    1989-01-01

    A simultaneous study of cockroach (Supella supellectilium) distribution and of associated carried bacterial flora has been made in the main hospital in Rennes (France). Wild cockroaches carry a high number of bacterial species that can be related to the normal environmental flora and a contaminant flora acquired from particular environments. The diversity of carried bacterial species reveals a proximity factor between continguous floors of the building which leads us to suppose that cockroach...

  5. Study on Early Warning of Traffic Resources and Environment Carrying Capacity%交通资源环境承载力预警研究

    Institute of Scientific and Technical Information of China (English)

    蒋恵园; 黄永燊

    2015-01-01

    新常态下快速发展的综合交通运输对资源环境的胁迫作用日益明显,资源环境对交通运输的承载能力成为地区健康发展的重要衡量标准。在界定交通资源环境承载力概念的基础上,从资源承载力和生态环境承载力两个方面构建交通资源环境承载力指标体系。结合可拓学的模糊物元理论和信息论的熵理论,建立基于模糊物元的交通资源环境承载力的预警模型,并对长江经济带七省二市的交通资源环境承载力进行预警研究。实例结果表明,构建的交通资源环境承载力指标体系基本合理,模糊物元预警模型在资源环境承载力的预警研究中具有较强的适用性和可操作性。%The rapid development of integrated transportation in the new normal poses an increasing threat to environment and resources. The bearing capacity of environment and resources to transportation becomes a significant criterion to measure whether an area is developing healthily. Based on the definition of traffic resource environmental bearing capacity, a traffic resource and environmental bearing capacity index system is built from both resources carrying capacity and environmental carrying capacity aspects. Through combining fuzzy matter-element theory of extension theory with entropy theory, an early-warning model of traffic resource and environmental bearing capacity is established, this model is applied to study the traffic resources and environmental carrying capacity of Yangtze River economic belt (include seven provinces and two municipalities as well). The results demonstrate that:The traffic resources and environmental carrying capacity index system is reasonable and the fuzzy matter-element model used in studying the early-warning of resources environmental bearing capacity is of sound applicability and operability.

  6. Assessment of water ecological carrying capacity under the two policies in Tieling City on the basis of the integrated system dynamics model.

    Science.gov (United States)

    Wang, Shuo; Xu, Ling; Yang, Fenglin; Wang, He

    2014-02-15

    Considering the limitation of the traditional method to assess the ecological carrying capacity and the complexity of the water ecological system, we used system dynamics, ANN, and CA-Markov to model a water ecological system. The social component was modeled according to Granger causality test by system dynamics. The natural component consists of the water resource and water environmental capacity, which were forecasted through the prediction of precipitation and change in land use cover. The interaction of the social component and the natural component mainly reflected environmental policies, such as the imposition of an environmental fee and environmental tax based on their values. Simulation results showed the different assessments on water ecological carrying capacity under the two policies. The population grew (2.9 million), and less pollution (86,632.37 t COD and 2854.5 t NH4N) was observed with the imposition of environmental tax compared with the imposition of an environmental fee (2.85 million population, 10,8381 t COD and 3543 t NH4N) at the same GDP level of 585 billion CNY in 2030. According to the causality loop, we discussed the different states under the policies and the reasons that caused the differences in water ecological carrying capacity state. According to game theory, we explained the limitation of the environmental fee policy on the basis of marginal benefit and cost. The externality was cleared up by the environmental tax policy. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Water ecological carrying capacity of urban lakes in the context of rapid urbanization: A case study of East Lake in Wuhan

    Science.gov (United States)

    Ding, Lei; Chen, Kun-lun; Cheng, Sheng-gao; Wang, Xu

    With the excessive development of social economy, water scarcity and water environment deterioration become a common phenomenon in metropolis. As a crucial component of urban water environment system, urban lake is mainly influenced by social economic system and tourism system. In this paper, a framework for quantitatively evaluating development sustainability of urban lake was established by a multi-objective model that represented water ecological carrying capacity (WECC). And nine key indicators including population, irrigation area, tourist quantity, the average number of hotel daily reception, TP, TN, CODMn, BOD5 were chosen from urban social-economy system and natural resilience aspects, with their index weight was determined by using the Structure Entropy Weight method. Then, we took Wuhan East Lake, the largest urban lake in China as a case study, and selected five time sections including 2002, 2004, 2007, 2009 and 2012 to synthetically evaluate and comparatively analyze the dynamic change of WECC. The results showed that: firstly, the water ecological carrying capacity values of the East Lake in five time sections were 1.17, 1.07, 1.64, 1.53 and 2.01 respectively, which all exceeded 1 and increased fluctuation. The rapid growth of population and GDP lead to sharply increasing demand for water quantity. However, a large amount of the domestic sewage and industrial waste led by economic development increases pressure on ecological environment of urban lakes. Secondly, the carrying capacity of the East Lake for tourist activities was still low. The value in 2012 was only 0.22, keeping at a slowly increasing phase, which indicates that the East Lake has large opportunity and space for developing the water resource carrying capacity and could make further efforts to attract tourists. Moreover, the WECC of the East Lake was mainly affected by rapid social and economic development and water environment damage caused by organic pollutants. From the view of urban

  8. Sustainability assessment of forest biomass supply chain at local scale: carrying capacity of the system for energy valorisation

    OpenAIRE

    Martire, S; Castellani, V.; Sala, S.

    2011-01-01

    Evaluation of the trade-off between the benefits coming from forest resources’ use and the conservation of forest ecosystems is needed. Considering the use of biomass for energy purpose, on one hand the use of wood resources should be based on an evaluation of the “carrying capacity” of the forest ecosystem and site-specific characteristics; on the other hand, the role of biomass valorisation has to be assessed considering the socio economic benefit or drawbacks due to the further development...

  9. Range Analysis and Terrain Preference of Adult Southern White Rhinoceros (Ceratotherium simum) in a South African Private Game Reserve: Insights into Carrying Capacity and Future Management.

    Science.gov (United States)

    Thompson, S; Avent, T; Doughty, L S

    2016-01-01

    The Southern white rhinoceros (Ceratotherium simum) is a threatened species, central to the tourism appeal of private game reserves in South Africa. Privately owned reserves in South Africa tend to be smaller than government run reserves such as Kruger National Park. Because of their relatively small size and the often heterogeneous nature of the landscape private game reserve managers benefit from detailed knowledge of white rhinoceros terrain selection preferences, which can be assessed from their ranging behaviours. We collected adult and sub-adult white rhinoceros distribution data over a 15 month period, calculating individual range size using kernel density estimation analysis within a GIS. From this, terrain selectivity was calculated using 50% and 95% kernels to extract terrain composition values. Jacob's correction of the Ivlev's selectivity index was subsequently applied to the terrain composition of each individual to identify trends in selectivity. Results reveal that adult males hold exclusive territories considerably smaller than those found in previous work conducted in "open" or large reserves. Similarly, results for the size of male versus female territories were also not in keeping with those from previous field studies, with males, rather than females, having the larger territory requirement. Terrain selection for both genders and age classes (adult and sub-adult) showed a strong preference for open grassland and avoidance of hill slope and riparian terrains. This research reveals white rhinoceros terrain selection preferences and how they influence range requirements in small, closed reserves. We conclude that this knowledge will be valuable in future white rhinoceros conservation management in small private game reserves, particularly in decisions surrounding removal of surplus individuals or augmentation of existing populations, calculation of reserve carrying capacity and future private reserve acquisition.

  10. Range Analysis and Terrain Preference of Adult Southern White Rhinoceros (Ceratotherium simum) in a South African Private Game Reserve: Insights into Carrying Capacity and Future Management

    Science.gov (United States)

    Thompson, S.; Doughty, L. S.

    2016-01-01

    The Southern white rhinoceros (Ceratotherium simum) is a threatened species, central to the tourism appeal of private game reserves in South Africa. Privately owned reserves in South Africa tend to be smaller than government run reserves such as Kruger National Park. Because of their relatively small size and the often heterogeneous nature of the landscape private game reserve managers benefit from detailed knowledge of white rhinoceros terrain selection preferences, which can be assessed from their ranging behaviours. We collected adult and sub-adult white rhinoceros distribution data over a 15 month period, calculating individual range size using kernel density estimation analysis within a GIS. From this, terrain selectivity was calculated using 50% and 95% kernels to extract terrain composition values. Jacob’s correction of the Ivlev’s selectivity index was subsequently applied to the terrain composition of each individual to identify trends in selectivity. Results reveal that adult males hold exclusive territories considerably smaller than those found in previous work conducted in “open” or large reserves. Similarly, results for the size of male versus female territories were also not in keeping with those from previous field studies, with males, rather than females, having the larger territory requirement. Terrain selection for both genders and age classes (adult and sub-adult) showed a strong preference for open grassland and avoidance of hill slope and riparian terrains. This research reveals white rhinoceros terrain selection preferences and how they influence range requirements in small, closed reserves. We conclude that this knowledge will be valuable in future white rhinoceros conservation management in small private game reserves, particularly in decisions surrounding removal of surplus individuals or augmentation of existing populations, calculation of reserve carrying capacity and future private reserve acquisition. PMID:27622566

  11. Tourism monitoring system based on the concept of carrying capacity The case of the regional natural park Pfyn-Finges (Switzerland)

    OpenAIRE

    Michelet, Jacques Félix; Clivaz, Christophe; Hausser, Yves

    2004-01-01

    The creation of regional natural parks offers the possibility of improving the economic situation of peripheral regions. However, the use of ecologically sensitive zones for tourism also presents economic, environmental and social problems. The concept of carrying capacity is often presented as a useful approach for determining the intensity of tourism development that can be supported by a region. Our objective thus consisted in the operationalisation of this concept by defining a certain nu...

  12. 水环境承载能力及其测算研究%Study on Water Environment Carrying Capacity and Calculation

    Institute of Scientific and Technical Information of China (English)

    胡秋玲

    2014-01-01

    From the water resources carrying capacity situation,concept and connotation,three calculation methods for water environment carrying capacity is introduced,namely mathematical model, comprehensive index system evaluation and analytical method of multi-objective model of water environment carrying capacity,etc.At the same time,a brief analysis of the principle of three kinds of calculation methods and the advantages and disadvantages is conducted in order to draw attention to the relevant departments for always maintaining good water ecological system as the goal,strengthening the study on ecological water requirement,establishing the common model of water environment carrying capacity based on existing calculation models.%文章从水资源承载能力的现状、概念和内涵出发,介绍了3种常用的水环境承载能力测算方法,即数学模型法、综合指标体系评价方法和水环境承载力多目标模型分析方法。同时简要分析了3种测算方法的原理和优缺点,以期引起相关部门重视以水体始终保持良好生态系统为目标,加强生态需水量研究,在对现有测算模型进行融合贯通的基础上,建立能够综合反映水环境承载能力的通用评价模型。

  13. Movement of Fuel Ashore: Storage, Capacity, Throughput, and Distribution Analysis

    Science.gov (United States)

    2015-12-01

    planning and forecasting approach. It is the aim of this study to understand the connection between the GCE’s operational behavior and its fuel demand...of the seabased logistics network will depend on the use of a modern planning and forecasting approach. It is the aim of this study to understand the...capability and interoperability. These systems, while innovative , lack the capacity to efficiently resupply and sustain the forces ashore. Even with

  14. New approach for determination of an optimum honeybee colony's carrying capacity based on productivity and nectar secretion potential of bee forage species.

    Science.gov (United States)

    Al-Ghamdi, Ahmed; Adgaba, Nuru; Getachew, Awraris; Tadesse, Yilma

    2016-01-01

    The present study was carried out to determine an optimum honeybee colony's carrying capacity of selected valleys dominated by Ziziphus spina-christi and Acacia tortilis in the Al-Baha region, Kingdom of Saudi Arabia. The study was conducted based on the assessment of the number of colonies kept, their productivities and the existing productive bee forage resources in the target valleys with its economic implication. In the existing beekeeping practice, the average number of managed honeybee colonies introduced per square kilometer was 530 and 317 during the flowering period of Z. spina-christi and A. tortilis, respectively. Furthermore, the overall ratios of productive bee forage plants to the number of honeybee colonies introduced were 0.55 and 11.12 to Ziziphus trees and A. tortilis shrubs respectively. In the existing situation the average honey production potential of 5.21 and 0.34 kg was recorded per Ziziphus and A. tortilis plants per flowering season, respectively. The present study, revealed that the number of honeybee colonies introduced in relation to the existing bee forage potential was extremely overcrowding which is beyond the carrying capacity of bee forage resources in selected valleys and it has been observed to affect the productivities and subsequent profitability of beekeeping. The study infers that, by keeping the optimum honeybee colony's carrying capacity of valleys (88 traditional hives/km(2) or 54 Langstroth hives/km(2) in Ziziphus field and 72 traditional hives/km(2) or 44 Langstroth hives/km(2) in A. tortilis field), profitability of beekeeping can be boosted up to 130.39% and 207.98% during Z. spina-christi and A. tortilis, flowering seasons, respectively.

  15. Direct FEM-computation of load carrying capacity of highly loaded passive components; Direkte FEM - Berechnung der Tragfaehigkeit hochbeanspruchter passiver Komponenten

    Energy Technology Data Exchange (ETDEWEB)

    Staat, M.; Heitzer, M. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Sicherheitsforschung und Reaktortechnik

    1998-11-01

    Detailed, inelastic FEM analyses yield accurate information about the stresses and deformations in passive components. The local loading conditions, however, cannot be directly compared with a limit load in terms of structural mechanics. Concentration on the load carrying capacity is an approach simplifying the analysis. Based on the plasticity theory, limit and shakedown analyses calculate the load carrying capacities directly and exactly. The paper explains the implementation of the limit and shakedown data sets in a general FEM program and the direct calculation of the load carrying capacities of passive components. The concepts used are explained with respect to common structural analysis. Examples assuming high local stresses illustrate the application of FEM-based limit and shakedown analyses. The calculated interaction diagrams present a good insight into the applicable operational loads of individual passive components. The load carrying analysis also opens up a structure mechanics-based approach to assessing the load-to-collapse of cracked components made of highly ductile fracture-resistant material. (orig./CB) [Deutsch] Genaue Kenntnis der Spannungen und Verformungen in passiven Komponenten gewinnt man mit detailierten inelastischen FEM Analysen. Die lokale Beanspruchung laesst sich aber nicht direkt mit einer Beanspruchbarkeit im strukturmechanischen Sinne vergleichen. Konzentriert man sich auf die Frage nach der Tragfaehigkeit, dann vereinfacht sich die Analyse. Im Rahmen der Plastizitaetstheorie berechnen Traglast- und Einspielanalyse die tragbaren Lasten direkt und exakt. In diesem Beitrag wird eine Implementierung der Traglast- und Einspielsaetze in ein allgemeines FEM Programm vorgestellt, mit der die Tragfaehigkeit passiver Komponenten direkt berechnet wird. Die benutzten Konzepte werden in Bezug auf die uebliche Strukturanalyse erlaeutert. Beispiele mit lokal hoher Beanspruchung verdeutlichen die Anwendung der FEM basierten Traglast- und

  16. Resource and Environment Carrying Capacity and Sustainable Development%资源环境承载力与区域可持续发展

    Institute of Scientific and Technical Information of China (English)

    廖慧璇; 籍永丽; 彭少麟

    2016-01-01

    实施“可持续发展战略”是世界各国的发展共识。可持续发展理念的核心是经济发展、资源保护和生态环境保护相协调统一。资源环境承载力是制定可持续发展战略规划的基础。只有准确衡量区域的资源环境承载力,才能从整体上以承载力为约束对国土空间进行科学规划,引导社会经济活动在资源节约、环境保护的基础上科学发展,从而实现区域的可持续发展。文章综述了与区域可持续发展密切相关的四大类资源承载力(包括土地资源、水资源、能源资源和生物资源承载力)和两大类环境承载力(包括空气环境和水环境承载力)的重要性。在综合我国国家标准文件和研究论文的基础上,总结了四大类资源承载力和两大类环境承载力的主要评价指标和评价标准。更进一步,结合我国的资源承载力和可持续发展的研究和实践现状,从研究内容和指标体系构建两方面着眼,指出应尽快制定符合我国国情的评价标准和综合评价体系,并通过简化评价过程来提高资源环境承载力评价的可操作性。%More and more countries have implemented the principle of “sustainable development” into their own development agenda. The key to “sustainable development” is to keep a perfect balance among economic development, resource conservation and environment protection. As the estimations of the magnitudes of the economic development and human population that can be supported by the resource and environment in an area, resource and environment carrying capacities is the foundation of any actions implementing “sustainable development”. Only with the accurate measurements on the resource and environment carrying capacities, will we be able to device developmental plans that take into account of the limiting resources or the worsening environmental conditions, so that “sustainable development” can

  17. The Study on Free Vibration of Elastically Restrained Beams Carrying Various Types of Attachments with Arbitrary Spatial Distributions

    Directory of Open Access Journals (Sweden)

    Heye Xiao

    2013-01-01

    Full Text Available The flexible beams carrying attachments often appear in engineering structures, modal analysis of those structures is important and necessary in structural design. This manuscript develops a proposed analytical method as a general tool for solving the free vibration of varying cross-section beams carrying various types of attachments with different distributions and arbitrary boundary conditions. In current practice, the natural frequencies of beam carrying lumped and uniform sprung mass and resting on Pasternak soil are calculated and compared with those in references to verify the methodology firstly. Then, the natural frequencies of beam carrying non-uniform spring-mass systems and stepped beam on Pasternak soil are calculated by the proposed method to study free vibration of beam carrying attachments with non-uniform cross section or distribution. Finally, some important conclusions are derived from results, which reveal that distribution density of spring-mass system at peaks of the mode shape makes dominate effects on the change of the natural frequencies at that mode and the natural frequencies of the stepped beam resting on elastic foundation are more sensitive to the increase of soil parameters.

  18. Problem in application carrying capacity approach for land allocation assessment in Indonesian municipal spatial planning: A case of Kutai Kartanegara Regency

    Science.gov (United States)

    Wijaya, I. N. S.; Rahadi, B.; Lusiana, N.; Maulidina, I.

    2017-06-01

    Urbanization in many countries, such as Indonesia, is commonly appeared as a dynamic population of developed areas. It is followed with reducing rural uses of land for improving urban land uses such as housing, industry, infrastructure, etc. in response to the growth of population. One may not be sufficiently considered by the urban planners and the decision makers, urbanization also means escalation of natural resources consumption that should be supported by the natural capacity of the area. In this situation, balancing approach as carrying capacity calculation in spatial planning is needed for sustainability. Indonesian Spatial Planning Law 26/2007 has already expressed about the balance approach in the system. Moreover, it strictly regulates the assessment and the permission system in controlling land development, especially for the conversion. However, the reductions over the rural uses of land, especially agriculture, are continuously occurred. Concerning the planning approach, this paper aims to disclose common insufficiency of carrying capacity considerations in Indonesian spatial planning practice. This paper describes common calculation weaknesses in projecting area for the urban development by recalculating the actual gap between supply and demand of agriculture land areas. Here, municipal spatial plan of Kutai Kartanegara Regency is utilized as single sample case to discuss. As the result, the recalculation shows that: 1) there are serious deficit status of agriculture land areas in order to fulfil the demanded agriculture production for the existed population, 2) some calculation of agriculture production may be miss-interpreted because of insufficient explanation toward the productivity of each agriculture commodity.

  19. Marine Carrying Capacity Assessment and Spatio-temporal Analysis in the Bohai Sea Ring Area, China%环渤海地区海域承载力测度与时空分异分析

    Institute of Scientific and Technical Information of China (English)

    孙才志; 于广华; 王泽宇; 刘锴; 刘桂春

    2014-01-01

    the situation of the membership level of things to be judged from multiple factors. Marine carrying capacity assessment is a comprehensive evaluation issue which related to multiple factors, and there are a lot of uncertain, fuzzy factors, so it can be evaluated by fuzzy comprehensive evaluation method. In view of the shortage of previous studies, this article applied Weber-Fischna law to deter-mine classification standards of assessment indexes, and used D-S evidential theory to combine the subjective factor weights and objective weights, in order to make integrated weight more reliable and accurate. Informa-tion diffusion technique was used to determine the information distribution of small sample indexes value on the domain, and then determine the degree of membership. Finally used the fuzzy comprehensive evaluation method to assess marine carrying capacity in the Bohai Sea Ring Area, and used Natural Breaks to express the spatial distribution. The results show that although the marine carrying capacity from 2000 to 2011 of 17 coast-al cities in the Bohai Sea Ring Area had fluctuations but it had an upward trend on the whole and continuously improve. But level characteristics values are all between 1.8 and 4, which means marine carrying capacity are not high. There is an obvious regional spatial difference and peak effect in marine carrying capacity.%采用韦伯-费希纳定律确定指标评价标准,通过D-S证据合成理论将主客观权重相结合确定综合权重,应用信息扩散技术确定小样本情况下样本指标值在指标评价域上的信息分配,进而确定隶属度,在此基础上利用模糊综合评判方法对环渤海17个沿海城市的海域承载力进行评价,并运用自然断裂法进行空间表达。研究结果表明,2000~2011年,环渤海地区海域承载力虽有波动,但总体上呈上升趋势,各地海域承载力不断提高,但级别特征值都在1.8~4.0之间,整体水平不高;区域空

  20. Emergy measures of carrying capacity and sustainability of a target region for an ecological restoration programme: a case study in Loess Hilly Region, China.

    Science.gov (United States)

    Dang, Xiaohu; Liu, Guobin

    2012-07-15

    Evaluating the sustainability of a target region for an ecological restoration programme is challenging because it involves different aspects of human society and environment as well as multiple disciplines. Carrying capacity provides a useful measure of the sustainability of a given region where an ecological restoration programme is implemented. In this article, the Yangou catchment, a geomorphic unit, was used as a case study in the Loess Hilly Region of China, where emergy synthesis was used to measure the environmental resources base. The specific standard of living in terms of emergy was employed to calculate carrying capacity over the period 1998-2005 and to assess the sustainability of the Yangou catchment where an ecological restoration programme was carried out. The results of the evaluation indicated that after implementing the ecological restoration programme, there was some improvement in the environmental aspects of the Yangou catchment during the study period, suggesting that the ecological restoration programme alleviated ecological degradation. However, several emergy-based indices and the support areas also illustrated that the ecological restoration programme was not successful enough in terms of preservation and utilisation of environmental resources to enhance sustainability. This indicates that further actions are necessary on conserving environmental resources, improving the emergy input structure for agricultural production and in lifestyle changes for the local people in living in the Yangou catchment.

  1. Yeast NDI1 Improve Oxidative Phosphorylation Capacity and Increases Protection Against Oxidative Stress and Cell Death in Cells Carrying a Leber’s Hereditary Optic Neuropathy Mutation

    Science.gov (United States)

    Park, Jeong Soon; Li, You-fen; Bai, Yidong

    2007-01-01

    G11778A in the subunit ND4 gene of NADH dehydrogenase complex is the most common primary mutation found in Leber’s hereditary optic neuropathy (LHON) patients. The NDI1 gene, which encodes the internal NADH -quinone oxidoreductase in Saccharomyces cerevisiae, was introduced into the nuclear genome of a mitochondrial defective human cell line, Le1.3.1, carrying the G11778A mutation. In transformant cell lines, LeNDI1-1 and -2, total and complex I-dependent respiration were fully restored and largely resistant to complex I inhibitor, rotenone, indicating a dominant role of NDI1 in the transfer of electrons in the host cells. Whereas the original mutant Le1.3.1 cell grows poorly in medium containing galactose, the transformants have a fully restored growth capacity in galactose medium, although the ATP production was not totally recovered. Furthermore, the increased oxidative stress in the cells carrying the G11778A mutation was alleviated in transformants, demonstrated by a decreased reactive oxygen species (ROS) level. Finally, transformants were also shown to be desensitized to induction to apoptosis and also exhibit greater resistance to paraquat-induced cell death. It is concluded that the yeast ND11 enzyme can improve the oxidative phosphorylation capacity in cells carrying the G11778A mutation and protect the cells from oxidative stress and cell death. PMID:17320357

  2. Yeast NDI1 improves oxidative phosphorylation capacity and increases protection against oxidative stress and cell death in cells carrying a Leber's hereditary optic neuropathy mutation.

    Science.gov (United States)

    Park, Jeong Soon; Li, You-Fen; Bai, Yidong

    2007-05-01

    G11778A in the subunit ND4 gene of NADH dehydrogenase complex is the most common primary mutation found in Leber's hereditary optic neuropathy (LHON) patients. The NDI1 gene, which encodes the internal NADH-quinone oxidoreductase in Saccharomyces cerevisiae, was introduced into the nuclear genome of a mitochondrial defective human cell line, Le1.3.1, carrying the G11778A mutation. In transformant cell lines, LeNDI1-1 and -2, total and complex I-dependent respiration were fully restored and largely resistant to complex I inhibitor, rotenone, indicating a dominant role of NDI1 in the transfer of electrons in the host cells. Whereas the original mutant Le1.3.1 cell grows poorly in medium containing galactose, the transformants have a fully restored growth capacity in galactose medium, although the ATP production was not totally recovered. Furthermore, the increased oxidative stress in the cells carrying the G11778A mutation was alleviated in transformants, demonstrated by a decreased reactive oxygen species (ROS) level. Finally, transformants were also shown to be desensitized to induction to apoptosis and also exhibit greater resistance to paraquat-induced cell death. It is concluded that the yeast NDI1 enzyme can improve the oxidative phosphorylation capacity in cells carrying the G11778A mutation and protect the cells from oxidative stress and cell death.

  3. Development of urbanization in arid and semi arid regions based on the water resource carrying capacity -- a case study of Changji, Xinjiang

    Science.gov (United States)

    Xiao, H.; Zhang, L.; Chai, Z.

    2017-07-01

    The arid and semiarid region in China where have a relatively weak economic foundation, independent development capacity, and the low-level of urbanization. The new urbanization within these regions is facing severe challenges brought by the constraints of resources. In this paper, we selected the Changji Hui Autonomous Prefecture, Xinjiang Uyghur Autonomous Region as study area. We found that agricultural planting structure is the key water consumption index based on the research about the main water demands of domestic, agriculture and industry. Finally, we suggest that more attentions should be paid to the rational utilization of water resources, population carrying capacity, and adjust and upgrade the industrial structure, with the purpose of coordination with the Silk Road Economic Belt.

  4. Studies about the current carrying capacity of the devices of the electric power transmission depending on the ambient conditions; Untersuchungen zur Strombelastbarkeit der Geraete der Elektroenergieuebertragung unter Freiluftatmosphaere

    Energy Technology Data Exchange (ETDEWEB)

    Berg, Ina

    2011-07-01

    Due to the liberalization of the electricity market and the increasing expansion of the generation of wind power the transport of electric power in the power grid is increasing. Due to that the electrical equipment is loaded higher up to its thermal limits. However the electrical power supply should be anytime reliable. Because the new construction and upgrade of overhead lines and substations is expensive and approval procedures can take up to ten years, solutions have to be found, to ensue in short and medium term the transport of electrical power through the power grid. In this paper a possibility is introduced and analyzed to increase the current carrying capacity of the electrical equipment without carrying out extensive reconstructions or new buildings. For that the method of thermal networks is used. For the different devices of the electric power transmission (overhead lines, electrical fittings, circuit-breaker, disconnecting switch and current transformer) thermal networks are designed. The heating on examples of all devices was studied and tested under laboratory conditions and the thermal networks were verified. By expansion of the thermal networks with elements for forced convection (wind velocity) and additional heat sources (solar radiation) the ambient conditions were considered. With the help of the so expanded thermal networks parameter studies depending on the wind velocity, ambient temperature and solar radiation were carried out. The studies showed that depending on the ambient conditions the current carrying capacity of all devices can be increased without changing the devices. The rated currents of all devices are specified for a high ambient temperature (e.g. 35 C) and low wind speed (e.g. 1 m/s). Most of the time in a year the ambient temperature is lower and the wind speed is higher than the specified values. So the devices can carry a higher current than the rated current without exceeding its thermal limits. The calculations show the

  5. Carrying capacity of coral reefs

    Digital Repository Service at National Institute of Oceanography (India)

    Wafar, M.V.M.

    The sustainable yield of a commercially exploited fishery is assessed by the biological and environmental factors (including fishing effort). These parameters with a reef are vastly diverse-size, location, species diversity, productivity type...

  6. Opportunistic Scheduling in Heterogeneous Networks: Distributed Algorithms and System Capacity

    CERN Document Server

    Kampeas, Dor-Joseph; Gurewitz, Omer

    2012-01-01

    In this work, we design and analyze novel distributed scheduling algorithms for multi-user MIMO systems. In particular, we consider algorithms which do not require sending channel state information to a central processing unit, nor do they require communication between the users themselves, yet, we prove their performance closely approximates that of a centrally-controlled system, which is able to schedule the strongest user in each time-slot. Possible application include, but are not limited to, modern 4G networks such as 3GPP LTE, or random access protocols. The analysis is based on a novel application of the Point-Process approximation, enabling the examination of non-homogeneous cases, such as non-identically distributed users, or handling various QoS considerations, which to date had been open.

  7. Enhancing the Performance of Polymer Solar Cells by Using Donor Polymers Carrying Discretely Distributed Side Chains.

    Science.gov (United States)

    Gong, Xue; Li, Guangwu; Wu, Yang; Zhang, Jicheng; Feng, Shiyu; Liu, Yahui; Li, Cuihong; Ma, Wei; Bo, Zhishan

    2017-07-19

    Conjugated polymers with three components, P1-1 and P1-2, were prepared by one-pot Stille polymerization. The two-component polymer P1-0 is only composed of a 5-fluoro-6-alkyloxybenzothiadiazole (AFBT) acceptor unit and a thiophene donor unit, while the three-component polymers P1-1 and P1-2 contain 10% and 20% 5,6-difluorobenzothiadiazole (DFBT), respectively, as the third component. The incorporation of the third component, 5,6-difluorobenzothiadiazole, makes the side chains discretely distributed in the polymer backbones, which can enhance the π-π stacking of polymers in film, markedly increase the hole mobility of active layers, and improve the power-conversion efficiency (PCE) of devices. Influence of the third component on the morphology of active layer was also studied by X-ray diffraction (XRD), resonant soft X-ray scattering (R-SoXS), and transmission electron microscopy (TEM) experiments. P1-1/PC71BM-based PSCs gave a high PCE up to 7.25%, whereas similarly fabricated devices for P1-0/PC71BM only showed a PCE of 3.46%. The PCE of P1-1/PC71BM-based device was further enhanced to 8.79% after the use of 1,8-diiodooctane (DIO) as the solvent additive. Most importantly, after the incorporation of 10% 5,6-difluorobenzothiadiazole unit, P1-1 exhibited a marked tolerance to the blend film thickness. Devices with a thickness of 265 nm still showed a PCE above 8%, indicating that P1-1 is promising for future applications.

  8. Quantitative Evaluation of Sustainable Development and Eco-Environmental Carrying Capacity in Water-Deficient Regions:A Case Study in the Haihe River Basin, China

    Institute of Scientific and Technical Information of China (English)

    WANG Zhong-gen; LUO Yu-zhou; ZHANG Ming-hua; XIA Jun

    2014-01-01

    Quantitative assessment of development sustainability could be a challenge to regional management and planning, especially for areas facing great risks of water shortage. Surface-water decline and groundwater over-pumping have caused serious environmental problems and limited economic development in many regions all around the world. In this paper, a framework for quantitatively evaluating development sustainability was established with water-related eco-environmental carrying capacity (EECC) as the core measure. As a case study, the developed approach was applied to data of the Haihe River Basin, China, during 1998 through 2007. The overall sustainable development degree (SDD) is determined to be 0.39, suggesting that this rate of development is not sustainable. Results of scenario analysis revealed that overshoot, or resource over-exploitation, of the Basin’s EECC is about 20% for both population and economy. Based on conditions in the study area in 2007, in order to achieve sustainable development, i.e., SDD>0.70 in this study, the EECC could support a population of 108 million and gross domestic product (GDP) of 2.72 trillion CNY. The newly developed approach in quantifying eco-environmental carrying capacity is anticipated to facilitate sustainable development oriented resource management in water-deifcient areas.

  9. Giant panda (Ailuropoda melanoleuca) population dynamics and bamboo (subfamily Bambusoideae) life history: a structured population approach to examining carrying capacity when the prey are semelparous

    Science.gov (United States)

    Carter, J.; Ackleh, A.S.; Leonard, B.P.; Wang, Hongfang

    1999-01-01

    The giant panda, Ailuropoda melanoleuca, is a highly specialized Ursid whose diet consists almost entirely of various species of bamboo. Bamboo (Bambusoideae) is a grass subfamily whose species often exhibit a synchronous semelparity. Synchronous semelparity can create local drops in carrying capacity for the panda. We modeled the interaction of pandas and their bamboo food resources with an age structured panda population model linked to a natural history model of bamboo biomass dynamics based on literature values of bamboo biomass, and giant panda life history dynamics. This paper reports the results of our examination of the interaction between pandas and their bamboo food resource and its implications for panda conservation. In the model all panda populations were well below the carrying capacity of the habitat. The giant panda populations growth was most sensitive to changes in birth rates and removal of reproductive aged individuals. Periodic starvation that has been documented in conjunction with bamboo die-offs is probably related to the inability to move to other areas within the region where bamboo is still available. Based on the results of this model, giant panda conservation should concentrate on keeping breeding individuals in the wild, keep corridors to different bamboo species open to pandas, and to concentrate research on bamboo life history.

  10. Fuzzy assessment of water resources carrying capacity in Taihu Basin%太湖流域水资源承载能力模糊综合评价

    Institute of Scientific and Technical Information of China (English)

    孙远斌; 高怡; 石亚东; 徐枫

    2011-01-01

    Based on fully considering the status of water resources development and utilization and the socio-economic development in the Taihu Basin, a comprehensive evaluation index system of the water resources carrying capacity was established by using Driving forces-Pressure-State-Impact-Response (DPSIR) model, which put emphasis on the ecological environment impact factors and met the characteristics of the Taihu Basin.The indexes were classified according to water resources status, water resources and socio-economic and water resources and ecological environment.The AHP method was used to calculate the weights of each index and the fuzzy comprehensive evaluation of water resource carrying capacity in the Taihu Basin was carried out from 2000 to 2006.The evaluation results indicated that the overall level of the water resources carrying capacity in the Taihu Basin was contained in a critical state with the fitness and the overload, and its enhancement room was limited.%在充分考虑太湖流域水资源开发利用现状及社会经济发展状况的基础上,采用驱动力-压力-状态-影响-反应模型,突出生态环境影响因子,建立符合太湖流域自身特点的水资源承载能力综合评价指标体系,并按照水资源状态、水资源与社会经济、水资源与生态环境3个方面对指标进行分类,运用层次分析法计算各指标权重,对太湖流域2000-2006年水资源承载能力进行模糊综合评价.评价结果表明,太湖流域水资源承载能力总体水平处于适载与超载的临界状态,提升空间有限.

  11. Distribution System Augmented by DC Links for Increasing the Hosting Capacity of PV Generation

    DEFF Research Database (Denmark)

    Chaudhary, Sanjay; Demirok, Erhan; Teodorescu, Remus

    2012-01-01

    This paper presents a concept of enhancing the photovoltaic (PV) power generation hosting capacity of distribution networks. Distribution network serving electrical energy to farm settlements was selected as an example for their large roof area available for PV installation. Further, they are cha......This paper presents a concept of enhancing the photovoltaic (PV) power generation hosting capacity of distribution networks. Distribution network serving electrical energy to farm settlements was selected as an example for their large roof area available for PV installation. Further...

  12. 以崇左市为例的区域自然资源承载力研究%Study on Regional Natural Resource Carrying Capacity in Chongzuo City

    Institute of Scientific and Technical Information of China (English)

    覃玲玲

    2011-01-01

    Natural resource carrying capacity is important to the regional development and development scale. Through establishing the mathematical model of water resources carrying capacity, land resources carrying capacity and mineral resources carrying capacity, the methods of calculating and evaluating the natural resource carrying capacity were explored. Then taking Chongzuo as a example, the natural resource carrying capacity that in the year of 2010,2015,2020 were calculated, and the evaluation had been made that between the natural resource carrying capacity and the development. Conclusions were: Chongzuo have relatively large potential of water resources carrying capacity; carrying capacity of water resources don't overload in present and future; the carrying capacity of cultivated land resources overload in present, and the carrying capacity of construction land resources don't overload in present and future, these show that the land resource carrying capacity isn't safe; the mineral resources carrying capacity of limestone has relatively large potential to the economy; the mineral resources carrying capacity of coal and manganese ore will overload in 2015,2020.%通过建立水资源承载力、土地资源承载力、矿产资源承载力的数学模型,探索区域自然资源承载力的计算和评价方法;并以崇左市为例,计算崇左市2010现状年和2015年、2020年的自然资源承载力,然后评价自然资源对区域人口、经济社会发展及发展规模的承载能力.结果表明,崇左市水资源对区域的发展具有较好的承载能力,现状及未来均未出现超载;土地资源承载力中耕地资源承载力的现状已超载,建设用地资源承载力现状及未来均未超载,表明崇左市土地资源承载力存在一定安全隐患;矿产资源中水泥用石灰岩对经济发展的承载能力较强,煤炭和锰矿资源承载力在2015年和2020年均会超载.

  13. On the BICM Capacity - Part I: Binary Labelings, Arbitrary Input Distributions, and First-Order Asymptotics

    CERN Document Server

    Alvarado, Alex

    2010-01-01

    In this semitutorial paper (Part I of a two-part paper), the capacity of bit-interleaved coded modulation (BICM) is analyzed. We introduce a general model for BICM which considers all the variables affecting the BICM capacity: the binary labeling, the input distribution, and the signal set. We show that the relation between the BICM capacity and Eb/N0 is not always a one-to-one function, we analyze how to increase the BICM capacity by modifying the input symbol distribution, and we develop first-order asymptotics of the BICM capacity for constellations with arbitrary input distributions, dimensions, mean, variance, and binary labeling. For 8-ary pulse amplitude modulation (PAM) and around Es/N0=0 dB (0.75 bit/symbol), the folded binary code (FBC) results in a higher capacity than the binary reflected gray code (BRGC) and the natural binary code (NBC). For the same SNR, the 1 dB gap between the additive white Gaussian noise (AWGN) capacity and the BICM capacity can be reduced to 0.2 dB if the input symbol dist...

  14. Fostering the Capacity for Distributed Leadership: A Post-Heroic Approach to Leading School Improvement

    Science.gov (United States)

    Klar, Hans W.; Huggins, Kristin Shawn; Hammonds, Hattie L.; Buskey, Frederick C.

    2016-01-01

    Principals are being encouraged to distribute leadership to increase schools' organizational capacities, and enhance student growth and learning. Extant research on distributed leadership practices provides an emerging basis for adopting such approaches. Yet, relatively less attention has been paid to examining the principal's role in fostering…

  15. 农业生产与水资源承载力评价%Agricultural production and evaluation in terms of water resources carrying capacity

    Institute of Scientific and Technical Information of China (English)

    虞祎; 张晖; 胡浩

    2016-01-01

    AbstractBased on the evaluation of water resources carrying capacity, especially taking into account the impact of agricultural pollution on sustainable use of water resources, a comprehensive analysis was conducted on the strains of water resources due to farming and animal production in different regions of China to provide reference for rational estimation of potential agricultural growth and correct approaches for structural adjustments in agriculture. Excess nitrogen and grey water were calculated as indicators to quantify the impact of agricultural pollution on water resources. Following nutrient balance theory, excess nitrogen was the difference between the sum of nitrogen provided by chemical fertilizer, livestock manure and soil, and total nitrogen needed by farming. Grey water was the amount of water required for diluting excessively high concentration of nitrogen in water to a more environmental-friendly level. Agricultural water footprint was the sum of agricultural water and grey water used. The huge quantity of excess nitrogen produced by farming and livestock consequently led to excessive amount of grey water, which more than doubled the amount of water used in agriculture. There was therefore the need to reserve enough environmental space for diluting pollution when estimating water resources carrying capacity based on water sustainability and healthy development. Water surplus were constructed to reflect the potential of water resources to support agricultural production with detailed environmental consideration. Water surplus was the difference between water resources and agricultural water footprint. Using 2003-2012 nationwide samples, a panel data model was constructed to analyze the impact of change in sown area and livestock head on water surplus. The results suggested that the nationwide water in China could carry a maximum of 168.89 million hm2 or 3.57 billion pigs. The water resources carrying capacity model results also showed that the

  16. Constructing the probability distribution function for the total capacity of a power system

    Energy Technology Data Exchange (ETDEWEB)

    Vasin, V.P.; Prokhorenko, V.I.

    1980-01-01

    The difficulties involved in constructing the probability distribution function for the total capacity of a power system consisting of numerous power plants are discussed. A method is considered for the approximate determination of such a function by a Monte Carlo method and by exact calculation based on special recursion formulas on a particular grid of argument values. It is shown that there may be significant deviations between the true probability distribution and a normal distribution.

  17. Study on Macao's Comprehensive Land Carrying Capacity%澳门土地综合承载状况研究

    Institute of Scientific and Technical Information of China (English)

    陈相

    2012-01-01

    作为亚太有名的微型经济体,澳门有限的土地资源是备受关注以及重视的生产要素,它的规模以及承载上限直接制约着澳门经济与社会的可持续发展。通过对澳门土地综合承载状况进行实证研究发现,澳门目前显示处于超载的状态,经济与社会的发展给澳门土地所赋予的压力已超过澳门的承载上限。为了促进澳门的可持续发展,需要从完善规划和增加土地等多方面不断提高土地的承载上限。%As one of the micro economies in Asia-pacific, Macao has a limited land resource, which constitutes a major factor of production. The fact is its scale and maximum limit of carrying is impeding the development of its economy and society at large. The empirical analysis on Macao's comprehensive land carrying capacity finds Macao already surcharged. To seek for sustainable developments, Macao must raise the limit of land carrying by means of promoting city planning and adding land.

  18. Weaving versus blending: a quantitative assessment of the information carrying capacities of two alternative methods for conveying multivariate data with color.

    Science.gov (United States)

    Hagh-Shenas, Haleh; Kim, Sunghee; Interrante, Victoria; Healey, Christopher

    2007-01-01

    In many applications, it is important to understand the individual values of, and relationships between, multiple related scalar variables defined across a common domain. Several approaches have been proposed for representing data in these situations. In this paper we focus on strategies for the visualization of multivariate data that rely on color mixing. In particular, through a series of controlled observer experiments, we seek to establish a fundamental understanding of the information-carrying capacities of two alternative methods for encoding multivariate information using color: color blending and color weaving. We begin with a baseline experiment in which we assess participants' abilities to accurately read numerical data encoded in six different basic color scales defined in the L*a*b* color space. We then assess participants' abilities to read combinations of 2, 3, 4 and 6 different data values represented in a common region of the domain, encoded using either color blending or color weaving. In color blending a single mixed color is formed via linear combination of the individual values in L*a*b* space, and in color weaving the original individual colors are displayed side-by-side in a high frequency texture that fills the region. A third experiment was conducted to clarify some of the trends regarding the color contrast and its effect on the magnitude of the error that was observed in the second experiment. The results indicate that when the component colors are represented side-by-side in a high frequency texture, most participants' abilities to infer the values of individual components are significantly improved, relative to when the colors are blended. Participants' performance was significantly better with color weaving particularly when more than 2 colors were used, and even when the individual colors subtended only 3 minutes of visual angle in the texture. However, the information-carrying capacity of the color weaving approach has its limits. We

  19. Average capacity for optical wireless communication systems over exponentiated Weibull distribution non-Kolmogorov turbulent channels.

    Science.gov (United States)

    Cheng, Mingjian; Zhang, Yixin; Gao, Jie; Wang, Fei; Zhao, Fengsheng

    2014-06-20

    We model the average channel capacity of optical wireless communication systems for cases of weak to strong turbulence channels, using the exponentiation Weibull distribution model. The joint effects of the beam wander and spread, pointing errors, atmospheric attenuation, and the spectral index of non-Kolmogorov turbulence on system performance are included. Our results show that the average capacity decreases steeply as the propagation length L changes from 0 to 200 m and decreases slowly down or tends to a stable value as the propagation length L is greater than 200 m. In the weak turbulence region, by increasing the detection aperture, we can improve the average channel capacity and the atmospheric visibility as an important issue affecting the average channel capacity. In the strong turbulence region, the increase of the radius of the detection aperture cannot reduce the effects of the atmospheric turbulence on the average channel capacity, and the effect of atmospheric visibility on the channel information capacity can be ignored. The effect of the spectral power exponent on the average channel capacity in the strong turbulence region is higher than weak turbulence region. Irrespective of the details determining the turbulent channel, we can say that pointing errors have a significant effect on the average channel capacity of optical wireless communication systems in turbulence channels.

  20. Hosting Capacity of Solar Photovoltaics in Distribution Grids under Different Pricing Schemes

    DEFF Research Database (Denmark)

    Carollo, Riccardo; Chaudhary, Sanjay Kumar; Pillai, Jayakrishnan Radhakrishna

    2015-01-01

    and distributed battery storages, and locally absorb excess PV generation. This work analyzes the use of EV charging to increase the PV hosting capacity in LV networks, considering the electricity tariffs schemes like time-of-use (TOU) , net metering and Distribution Locational Marginal Pricing (DLMP) tariffs....... The results show that with the present TOU tariffs the EV integration in LV networks does not ease the grid bottlenecks for large PV penetration. Under the Net metering and DLMP the EV integration in LV grids tend to increase the PV hosting capacity....

  1. 重庆市近10年水资源承载力时空格局动态演变研究%Studies on Spatial and Temporal Evolution of Chongqing Water Ecological Carrying Capacity in Last Ten Years

    Institute of Scientific and Technical Information of China (English)

    张月; 杨华

    2012-01-01

    According to the basic principle and the calculation model of ecological footprint, the spatial patterns and dynamic laws of resources in Chongqing 2000 - 2009 were analyzed. The result showed that water resources per capita ecological footprint and per capita water resources capacity of Chongqing fluctuated in a downward trend. The ecological footprint of water resources fell from 3. 50 hm /person in 2000 to 2. 64 hm /person in 2009. Water resources carrying capacity fell from 6. 05 hm /person in 2000 to 3. 48 hm /person in 2009, and reached the trough period in 2001 and 2006. In the space, the ecological footprint of Chongqing waters resources and water resources carrying capacity showed obviously different spatial distribution. The water resources carrying capacity and ecological footprint of the developed metropolis and the west Chongqing were low. One of the most outstanding was the Yuzhong district. The water ecological footprint and water resources carrying capacity of Three Gorges reservoir and the southeast ecological was relatively high, especially in Chengkou County and Wuxi County. In addition , the 40 districts and counties of Chongqing general water resources ecological footprint was substantially below the carrying capacity of water resources. There were ecological surplus. But some of the districts of water resources ecological deficit were still serious.%以生态足迹理论为基础,通过水资源生态足迹模型研究了重庆市2000 ~ 2009年水资源生态足迹和水资源承载力时空格局动态演变.结果表明,近10年来,重庆市人均水资源生态足迹和人均水资源承载力波动呈下降的趋势,水资源生态足迹从2000年的3.50hm2/人下降到2009年的2.64 hm2/人,水资源承载力从2000年的6.05 hm2/人下降到2009年的3.48 hm2/人,并在2001年和2006年达到低谷期.在空间上,重庆市水资源生态足迹和水资源承载力空间差异较为明显,都市发达经济圈和渝西走廊的水资

  2. Analysis of Magnetic Field Distribution Under Power Lines with Changing Direction and Carrying Different Current%Analysis of Magnetic Field Distribution Under Power Lines with Changing Direction and Carrying Different Current

    Institute of Scientific and Technical Information of China (English)

    T. Matsumoto; H. Hirata; H. Tarao; N. Hayashi; K. Isaka

    2011-01-01

    Transmission power lines are a common source of extremely low frequency (ELF) magnetic fields which are usually analyzed as serial lines in one direction. Overhead vertical-type double-circuit power lines, which are generally used in Japan, sometimes carry different current for each circuit and change direction. In this paper, we focused on both the angle of direction change and the current balance in order to clarify the characteristics of distribution of magnetic fields at a height of 1 m. The magnetic field distributions were analyzed considering both the angle of power lines changing direction and the current balance of each circuit. The total magnetic field under overhead vertical-type double-circuit power lines with same current was generally reduced in comparison with that under a single-circuit power line due to phase difference. The total magnetic fields around the turning point where the change of transmission lines direction increased because each circuit came closer in that area. The component of Bz effect on total magnetic field was greatest around the maximum of total magnetic fields nearby the turning point.

  3. 云南省水资源生态足迹与生态承载力时空动态分析%Analysis of Water Resources Ecological Footprint and Ecological Carrying Capacity in Yunnan Province

    Institute of Scientific and Technical Information of China (English)

    常龙芳; 董金义

    2013-01-01

      应用水资源生态足迹计算模型对云南省近十年及各州(市)近五年水资源生态足迹和生态承载力进行了分析,结果表明:(1)云南省近十年水资源生态足迹变化不明显,而各年份之间的水资源生态承载力差异较大,2001年最高为285×106hm2,2009年最低为175×106hm2.(2)云南省水资源生态足迹较大的区域主要分布于滇中的昆明市和大理市、滇东的曲靖市以及滇东南的红河州,水资源生态足迹均大于2.00×106hm2,而较小的主要分布于滇西北的迪庆州、丽江市和怒江州,均小于1.00×106hm2.%This paper use the calculation model of water resources ecological footprint analyzing the water re-sources ecological footprint and ecological carrying capacity in the past ten years in Yunnan Province and the past five years in all city. The result shows: (1) The water resources ecological footprint in the past ten years is change not obvious in Yunnan province, but the water ecological carrying capacity change is obvious, the water resources ecological carrying capacity in 2001 is the highest for 285 ×106hm2, 2009 is the lowest for 175 × 106hm2. (3) The water resources ecological footprint larger area in Yunnan province mainly distribute in Kun-ming、Dali、Qujing and Honghe, all the water resources ecological footprint are more than 2.00 ×106hm2, and smaller mainly distribute in Diqing、Lijiang and Nujiang, all are less than 1.00×106hm2.

  4. Outage and Capacity Performance Evaluation of Distributed MIMO Systems over a Composite Fading Channel

    Directory of Open Access Journals (Sweden)

    Wenjie Peng

    2014-01-01

    Full Text Available The exact closed-form expressions regarding the outage probability and capacity of distributed MIMO (DMIMO systems over a composite fading channel are derived. This is achieved firstly by using a lognormal approximation to a gamma-lognormal distribution when a mobile station (MS in the cell is in a fixed position, and the so-called maximum ratio transmission/selected combining (MRT-SC and selected transmission/maximum ratio combining (ST-MRC schemes are adopted in uplink and downlink, respectively. Then, based on a newly proposed nonuniform MS cell distribution model, which is more consistent with the MS cell hotspot distribution in an actual communication environment, the average outage probability and capacity formulas are further derived. Finally, the accuracy of the approximation method and the rationality of the corresponding theoretical analysis regarding the system performance are proven and illustrated by computer simulations.

  5. Distributed generation hosting capacity calculation of MV distribution feeders in Turkey

    DEFF Research Database (Denmark)

    Altin, Müfit; Oguz, Emre Utku; Bizkevelci, Erdal

    2014-01-01

    Integration of distributed generation into distribution networks introduces new challenges to distribution system operators while the penetration level increases. One of the challenges is the voltage rise issue as a part of the steady-state analysis of DGs during planning and operational stages......-state voltage impacts introduced by DGs. Finally, a general flow chart of steady-state analysis is proposed for Turkish DSOs....

  6. Impact Analysis of Headway Distributions on Single-Lane Roundabout Entry Capacity

    Directory of Open Access Journals (Sweden)

    Liang Ren

    2016-01-01

    Full Text Available Based on observed data, this paper evaluates the performance of capacity estimation for single-lane roundabouts using the Highway Capacity Manual (HCM 2000 model. In this study, the HCM 2000 model is indicated to be over- or under estimate roundabout entry capacity. This is because the HCM 2000 model estimates capacity using an unfit assumption of headway distribution type. According to this finding, we propose a modified model to adjust the HCM 2000 model. Based on a comparison study, the modified model produces smaller relative error (0.92 and root-mean-square deviation (12.79 than the HCM 2000 model (4.66 and 48.17, respectively. It is believe that the modified HCM 2000 model outperforms the HCM 2000 model.

  7. Key Technology of Pilot’s Cognitive Decision-making Capacity Evaluation Based on Distributed Computing

    Directory of Open Access Journals (Sweden)

    Gui Chunmei

    2015-01-01

    Full Text Available To provide effective technological means for evaluation of the pilot’s information processing capacity for combat missions, tactical capability, command capability and cognitive decision-making capacity to compensate for the deficiency in the paper and pencil test, psychological dynamoscopy and other technological means used for traditional pilot’s cognitive decision-making capacity evaluation. Based on distributed computing technology, build a topological structure of the evaluation system, design a background of typical combat mission, and simulate combat control interface and process; based on software engineering, establish records, manage and analyze the evaluation technology of process data. The result of this study is that a scientific method and objective measurement means need to be provided for “real” evaluation of the pilot’s cognitive decision-making capacity.

  8. Finite element analysis of steel bar truss slab load-carrying capacity%钢筋桁架楼板承载力有限元分析

    Institute of Scientific and Technical Information of China (English)

    赵建忠; 孙磊; 王干

    2015-01-01

    钢筋桁架楼板在工程中的应用日益广泛,深入研究该楼板的受力性能有利于指导实际工程应用。文章采用有限元分析软件ANSYS对钢筋桁架楼板进行单调静力加载模拟,通过正交试验的方法对剪跨比、底部压型钢板、腹杆等影响因素进行研究。结果表明:楼板进入弹塑性阶段以后,试验中的4块带钢板的桁架楼板极限弯矩可提高30%左右,同时斜腹杆以及楼板的剪跨比对承载力也有较大的影响。对钢筋桁架楼板正截面受弯承载力计算公式进行补充和修改,达到了减轻结构自重、降低工程造价的目的。%In order to make a deep research on the structural behavior of steel bar truss slab,the FEM ANSYS was used to simulate monotonic static loading process of the slab. Through the analysis of different value of parameters of shear-span ratio,steel sheeting,diagonal web member,the same conclusion with the influence pattern of rigidity was achieved as well as the test. According to the results of the test,the formula of load-carrying capacity is advanced for future reference. Also,the shear-span ratio and diagonal web member will impact the capacity. Due to the beneficial effects of steel slabs were not considered,the suggestion was put forward to improve the correlation formulasto ease the weight of the structure and reduce the construction cost.

  9. Is DOM driver of the microbial carrying capacity in pristine porous groundwater ecosystems? - lab-scale experiments in 2D sediment flow-through microcosms

    Science.gov (United States)

    Hofmann, Roland; Griebler, Christian

    2017-04-01

    Groundwater ecosystems are an essential resource for drinking water and at the same time constitute fascinating habitats subject to increasing (anthropogenic) disturbances. In our research, we look for ways to qualitatively and quantitatively access, and predict the resistance and resilience (potential) of groundwater ecosystems in consequence of selected disturbances. As a central goal we hope to identify and quantify the underlying biological and ecological key drivers of the microbial Carrying Capacity (mCC) - an ecological concept established in macro-ecology - we assume directly connected to the ecosystem's productivity and the resistance and resilience of aquifers. We further hypothesize, that the ecosystems' mCC is a result of available energy and constitutes a promising proxy for the potential of groundwater ecosystems to withstand impacts and recover from it. In a first approach we studied the dynamics of the microbial standing stock (biomass) and growth (productivity) productivity of a natural groundwater microbial community in parallel 2-D sediment flow-through systems. Selected zones of the model aquifers were disturbed by elevated DOM concentrations. Both the 'mobile' (free floating) and 'sessile' (sediment attached) microbial components were followed over time in terms of biomass, growth, and specific activities (ATP, carbon use efficiency) and taxonomic composition. Sediment regions supplied with elevated concentrations of natural DOM showed increased biomass, activities and taxonomic richness with the sediment community, while differences in the mobile microbial were marginal. Specifically, the carbon use efficiency was significantly increased in the DOM amended sediment zones. In contrast, the microbial community that received the mainly refractory natural background DOM was able to metabolize polymers more efficiently in substrate use tests (ECOLOG), seen as an adaptation to the energy-poor subsurface. Quasi-stationary conditions were reached in

  10. Proceedings from a Workshop on Ecological Carrying Capacity of Salmonids in the Columbia River Basin : Measure 7.1A of the Northwest Power Planning Council`s 1994 Fish and Wildlife Program : Report 3 of 4, Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Neitzel, D.A.; Mavros, William V.

    1996-05-01

    This report contains the proceedings of a workshop held during 1995 in Portland, Oregon. The objective of the workshop was to assemble a group of experts that could help us define carrying capacity for Columbia River Basin salmonids. The workshop was one activity designed to answer the questions asked in Measure 7.1A of the Council`s Fish and Wildlife Program. Based, in part, on the information we learned during the workshop we concluded that the approach inherent in 7.1A will not increase understanding of ecology, carrying capacity, or limiting factors that influence salmon under current conditions. Measure 7.1A requires a definition of carrying capacity and a list of determinants (limiting factors) of capacity. The implication or inference then follows that by asking what we know and do not know about the determinants will lead to research that increases our understanding of what is limiting salmon survival. It is then assumed that research results will point to management actions that can remove or repair the limiting factors. Most ecologists and fisheries scientists that have studied carrying capacity clearly conclude that this approach is an oversimplification of complex ecological processes. To pursue the capacity parameter, that is, a single number or set of numbers that quantify how many salmon the basin or any part of the basin can support, is meaningless by itself and will not provide useful information.

  11. Network Capacity Assessment of CHP-based Distributed Generation on Urban Energy Distribution Networks

    Science.gov (United States)

    Zhang, Xianjun

    The combined heat and power (CHP)-based distributed generation (DG) or dis-tributed energy resources (DERs) are mature options available in the present energy market, considered to be an effective solution to promote energy efficiency. In the urban environment, the electricity, water and natural gas distribution networks are becoming increasingly interconnected with the growing penetration of the CHP-based DG. Subsequently, this emerging interdependence leads to new topics meriting serious consideration: how much of the CHP-based DG can be accommodated and where to locate these DERs, and given preexisting constraints, how to quantify the mutual impacts on operation performances between these urban energy distribution networks and the CHP-based DG. The early research work was conducted to investigate the feasibility and design methods for one residential microgrid system based on existing electricity, water and gas infrastructures of a residential community, mainly focusing on the economic planning. However, this proposed design method cannot determine the optimal DG sizing and siting for a larger test bed with the given information of energy infrastructures. In this context, a more systematic as well as generalized approach should be developed to solve these problems. In the later study, the model architecture that integrates urban electricity, water and gas distribution networks, and the CHP-based DG system was developed. The proposed approach addressed the challenge of identifying the optimal sizing and siting of the CHP-based DG on these urban energy networks and the mutual impacts on operation performances were also quantified. For this study, the overall objective is to maximize the electrical output and recovered thermal output of the CHP-based DG units. The electricity, gas, and water system models were developed individually and coupled by the developed CHP-based DG system model. The resultant integrated system model is used to constrain the DG's electrical

  12. Study of Mechanical Behavior and Ultimate Carrying Capacity of Suspender Anchorage Zone in Axial Direction of Bridge%顺置式吊杆锚固区受力特性与极限承载力研究

    Institute of Scientific and Technical Information of China (English)

    高小妮; 贺拴海; 齐宏学

    2012-01-01

    To have an understanding of the mechanical behavior and ultimate carrying capacity of suspender anchorage zone set in the axial direction of bridge under the action of suspender forces, a combined cable-stayed and self-anchored suspension system bridge that was being constructed was cited as an example, the software ANSYS was used to set up the spatial shell finite element model, the mechanical behavior of the anchorage zone under the action of the worst load was studied, the ultimate carrying capacity of the anchorage zone was analyzed, respectively u-sing the linear elasticity and nonlinearity analysis methods and the force conditions of the components in the anchorage zone were discussed. The results of the study show that under the action of the worst load, the stress in the steel anchor box and steel anchor beam is less than that in the diaphragm. With the exception that the stress concentration in the welding of the steel anchor beam and diaphragm is notable, the stress distribution in all components is uniform and the deformation of the components in the axial direction of the bridge is great. The results of the different analysis methods for the ultimate carrying capacity also show that when the ultimate carrying capacity of such type of the structure is analyzed, using the shell element model, the material nonlinearity should considered only and in the design of the structure, it is proposed that adequate attention should be paid to the problem of insufficient rigidity of the diaphragm.%为掌握顺桥向设置的吊杆锚固区在吊杆力作用下的受力特性和极限承载力,以某在建斜拉—自锚式悬索组合体系桥为依托工程,利用ANSYS软件建立壳单元空间有限元模型,对锚固区在最不利荷载作用下的受力性能进行研究;并分别采用线弹性及非线性分析方法对吊杆锚固区极限承载力进行分析,讨论构件的受力情况.结果表明:在最不利荷载作用下,钢锚箱及钢锚梁

  13. Subgrid Parameterization of the Soil Moisture Storage Capacity for a Distributed Rainfall-Runoff Model

    Directory of Open Access Journals (Sweden)

    Weijian Guo

    2015-05-01

    Full Text Available Spatial variability plays an important role in nonlinear hydrologic processes. Due to the limitation of computational efficiency and data resolution, subgrid variability is usually assumed to be uniform for most grid-based rainfall-runoff models, which leads to the scale-dependence of model performances. In this paper, the scale effect on the Grid-Xinanjiang model was examined. The bias of the estimation of precipitation, runoff, evapotranspiration and soil moisture at the different grid scales, along with the scale-dependence of the effective parameters, highlights the importance of well representing the subgrid variability. This paper presents a subgrid parameterization method to incorporate the subgrid variability of the soil storage capacity, which is a key variable that controls runoff generation and partitioning in the Grid-Xinanjiang model. In light of the similar spatial pattern and physical basis, the soil storage capacity is correlated with the topographic index, whose spatial distribution can more readily be measured. A beta distribution is introduced to represent the spatial distribution of the soil storage capacity within the grid. The results derived from the Yanduhe Basin show that the proposed subgrid parameterization method can effectively correct the watershed soil storage capacity curve. Compared to the original Grid-Xinanjiang model, the model performances are quite consistent at the different grid scales when the subgrid variability is incorporated. This subgrid parameterization method reduces the recalibration necessity when the Digital Elevation Model (DEM resolution is changed. Moreover, it improves the potential for the application of the distributed model in the ungauged basin.

  14. Operation Optimization Based on the Power Supply and Storage Capacity of an Active Distribution Network

    Directory of Open Access Journals (Sweden)

    Wenpeng Yu

    2013-12-01

    Full Text Available Due to the interconnection and active management of Distributed Generation (DG and Energy Storage Systems (ESSs, the traditional electrical distribution network has become an Active Distribution Network (ADN, posing challenges to the operation optimization of the network. The power supply and storage capacity indexes of a Local Autonomy Control Region (LACR, which consists of DGs, ESSs and the network, are proposed in this paper to quantify the power regulating range of a LACR. DG/ESS and the network are considered as a whole in the model of the indexes, considering both network constraints and power constraints of the DG/ESS. The index quantifies the maximum LACR power supplied to or received from ADN lines. Similarly, power supply and storage capacity indexes of the ADN line are also proposed to quantify the maximum power exchanged between ADN lines. Then a practical algorithm to calculate the indexes is presented, and an operation optimization model is proposed based on the indexes to maximum the economic benefit of DG/ESS. In the optimization model, the power supply reliability of the ADN line is also considered. Finally, the indexes of power supply and storage capacity and the optimization are demonstrated in a case study.

  15. Incorporación de la cobertura de escape en un modelo de capacidad de carga para venado de cola blanca Incorporation of escape cover in a model to estimate carrying capacity for white-tailed deer

    Directory of Open Access Journals (Sweden)

    FX Plata

    2013-01-01

    Full Text Available Los objetivos de este trabajo fueron evaluar la incorporación de la cobertura de escape en un modelo de capacidad de carga (K de venado cola banca, evaluar el modelo por análisis de sensibilidad y comparar la estimación de la K con el modelo versus un modelo basado en disponibilidad de nutrientes. El trabajo se desarrolló en la localidad de Santa Cruz Nuevo, Puebla, México, en un área de 50 km², donde se establecieron 13 transectos de 800 m de longitud por 6 de ancho y se colectó información para establecer la relación entre la cobertura de escape y la presencia de indicios de venado mediante regresión lineal. Dicha relación se incorporó en un modelo de estimación de K, después de lo cual se realizó un análisis de sensibilidad del mismo. Los indicios animales se observaron principalmente en las áreas con una cobertura de escape mayor al 59% y se distribuyeron en una forma cuadrática hasta llegar al 100%. El análisis de sensibilidad mostró que la cobertura de escape y la vegetación arbustiva fueron los principales componentes para aumentar la capacidad de carga, mientras que el peso vivo del venado para disminuirla.The objective of this study was to establish the incorporation of escape cover in a carrying capacity (K model for white-tailed deer (Odocoileus virginianus. The study was carried out in Santa Cruz Nuevo, Puebla, Mexico in an area of 50 Km². The information was gathered through 13 transects of 800 by six m. The information served to establish the relationship between the escape cover and the faecal pellets of deer using a linear regression analysis. The relationship was included in a model for estimation of K, then a sensibility analysis was conducted. Faecal pellets were found in areas with an escape cover bigger than 59% and they were distributed in a cubic arrangement until reaching the 100%. The sensibility analysis showed that the escape cover and the brush vegetation were the main components to increase the

  16. Spatio-temporal Difference of Coupling Coordinative Degree of Ecological Carrying Capacity in the Dongting Lake Region%洞庭湖区生态承载力系统耦合协调度时空分异

    Institute of Scientific and Technical Information of China (English)

    熊建新; 陈端吕; 彭保发; 邓素婷; 谢雪梅

    2014-01-01

    Ecological carrying capacity is a complex dynamic system including natural-economy-society, and its intrinsic coordination is the key to sustainable carrying capacity of ecosystem. In different spatio-temporal scales, the coupling coordinative degree of ecological carrying capacity presents different differences and changes. On the basis of coupling coordinative development interactive mechanism of ecological carrying ca-pacity, the article constructs an evaluation index system of coupling coordinative degree, and analyzes the tem-poral and spatial difference of coupling coordinative degree of ecological carrying capacity in the Dongting Lake region by using capacitive coupling model. The results show that:1) The trends of coupling degree and coupling coordinative degree of ecological carrying capacity in the Dongting Lake region from 2001 to 2012 seemed to be the same, and presented roughly steady upward trend. The mean of coupling degree was 0.499, in antagonistic stage; the mean of coupling coordinative degree was 0.463, in the moderate coupling coordina-tive phase;the average annual growth rate of coupling degree was 3.35%, greater than coupling coordinative degree, which was 3.05%. It indicated that the internal coupling and synergies of the ecological carrying capac-ity was obvious, and the coupling strength was greater than the internal coordination. 2) As to spatial variation, there were three states of coupling degree in three different years in 17 counties of the Dongting Lake area, which were a low coupling, antagonistic phase and running-in phase, each coupling state had different county number and interval change. The coupling coordinative degree appeared three states of low coupling coordina-tion, moderate coupling coordination and highly coupling coordination, the variation was substantially similar to the coupling degree, however the change of the county number and interval change in coordinative state laged behind the coupling degree. The spatial

  17. Watershed water ecological carrying capacity and optimizing regulation model%流域水生态承载力理论与优化调控模型方法

    Institute of Scientific and Technical Information of China (English)

    彭文启

    2013-01-01

    Watershed management is changing from single factor management of environment and re-sources to aquatic ecological protection integrated management. Water resources carrying capacity and water en-vironment carrying capacity have not fully adapted to this situation. Therefore,it is necessary to build a new car-rying capacity theory to solve the current aquatic problems. According to the demands of watershed water ecolog-ical integrity protection management,based on water ecological carrying capacity concept model,water ecologi-cal carrying capacity concept,which reveals its basic connotation of“partition,staging”property and“quanti-ty,quality,order”progressive comprehensive constraint effects,was put forward in this paper. Then the paper analyzed its key optimal regulation variables,and established the water ecological carrying capacity partition coupling concept model using eco-regions as elements. Considering the communication of water flow and water quality among eco-regions,the system dynamics simulation model of Taizi River basin water ecological carrying capacity was established,the water ecological carrying capacity of 8 eco-regions were simulated,and optional regulation schemes of each eco-regions were determined,which can provide a scientific basis for the sustainable development of the watershed.%  流域管理正在从环境及资源的单一要素管理向流域水生态系统综合管理转变,流域水生态承载力是流域水生态系统综合管理的基本理论。针对流域水生态完整性保护管理需求,建立了流域水生态承载力概念模型,提出了流域水生态承载力概念,揭示其“分区、分期”属性和“量、质、序”递进综合约束作用等基本内涵,通过分析其优化调控特性及优化调控关键变量,建立了流域水生态承载力分区耦合概念模型,形成了基于系统动力学方法的流域水生态承载力分区分期耦合模型方法,并以辽河

  18. 四川省水资源生态足迹与生态承载力的时空分析%Analysis of Spatio-Temporal Characteristics of Water Resources Ecological Footprint and Ecological Carrying Capacity in Sichuan Province

    Institute of Scientific and Technical Information of China (English)

    王文国; 何明雄; 潘科; 祝其丽; 周芸; 樊毅; 胡启春

    2011-01-01

    According to the basic principle and calculation model of water resources ecological footprint,the water resources ecological footprint and ecological carrying capacity in the years from 2001 to 2009 in Sichuan Province were analyzed.The results showed that the water resources ecological footprint per capita of Sichuan Province increased in the past nine years,while the water resources ecological footprint per 104 yuan GDP in Sichuan Province continued to decrease.This indicated that the utilization of water resources in Sichuan Province gradually increased in the past years.On the other hand,water resources ecological carrying capacity was impacted by drought,however,the ecological carrying capacity of water resources in Sichuan Province was more than the ecological footprint,the ecological surplus was existed.That is to say that the sustainable utilization of water resources in Sichuan Province was well.But the water resources in Sichuan were unevenly distributed.The economically backward western Sichuan where water resources are less demanded was rich in water resources and had large ecological surplus.On the contrary,the economically more developed eastern Sichuan where water resources are highly demanded was short in water resources and had small ecological surplus.Even in the cities of Mianyang,Suining,Neijiang and Zigong the ecological deficit appeared,showing a state of insecurity on utilization of water resources.The changes of ecological footprint of water resources were closely related to socio-economic development;it should fully considered the spatial-temporal distribution of water resources in Sichuan Province,adjusting the industrial structure,rational ma-nagement and use of water resources,promoted the sustainable development of the overall socio-economy of Sichuan Province.%根据水资源生态足迹的基本原理和计算模型,对四川省2001—2009年水资源生态足迹、生态承载力进行分析。结果表明,在2001—2009年间四

  19. A Capacity Design Method of Distributed Battery Storage for Controlling Power Variation with Large-Scale Photovoltaic Sources in Distribution Network

    Science.gov (United States)

    Kobayashi, Yasuhiro; Sawa, Toshiyuki; Gunji, Keiko; Yamazaki, Jun; Watanabe, Masahiro

    A design method for distributed battery storage capacity has been developed for evaluating battery storage advantage on demand-supply imbalance control in distribution systems with which large-scale home photovoltaic powers connected. The proposed method is based on a linear storage capacity minimization model with design basis demand load and photovoltaic output time series subjective to battery management constraints. The design method has been experimentally applied to a sample distribution system with substation storage and terminal area storage. From the numerical results, the developed method successfully clarifies the charge-discharge control and stored power variation, satisfies peak cut requirement, and pinpoints the minimum distributed storage capacity.

  20. Root anatomy and element distribution vary between two Salix caprea isolates with different Cd accumulation capacities.

    Science.gov (United States)

    Vaculík, Marek; Konlechner, Cornelia; Langer, Ingrid; Adlassnig, Wolfram; Puschenreiter, Markus; Lux, Alexander; Hauser, Marie-Theres

    2012-04-01

    The understanding of the influence of toxic elements on root anatomy and element distribution is still limited. This study describes anatomical responses, metal accumulation and element distribution of rooted cuttings of Salix caprea after exposure to Cd and/or Zn. Differences in the development of apoplastic barriers and tissue organization in roots between two distinct S. caprea isolates with divergent Cd uptake and accumulation capacities in leaves might reflect an adaptive predisposition based on different natural origins. Energy-dispersive X-ray spectroscopy (EDX) revealed that Cd and Zn interfered with the distribution of elements in a tissue- and isolate-specific manner. Zinc, Ca, Mg, Na and Si were enriched in the peripheral bark, K and S in the phloem and Cd in both vascular tissues. Si levels were lower in the superior Cd translocator. Since the cuttings originated from stocks isolated from polluted and unpolluted sites we probably uncovered different strategies against toxic elements.

  1. High-capacity quantum key distribution using Chebyshev-map values corresponding to Lucas numbers coding

    Science.gov (United States)

    Lai, Hong; Orgun, Mehmet A.; Pieprzyk, Josef; Li, Jing; Luo, Mingxing; Xiao, Jinghua; Xiao, Fuyuan

    2016-08-01

    We propose an approach that achieves high-capacity quantum key distribution using Chebyshev-map values corresponding to Lucas numbers coding. In particular, we encode a key with the Chebyshev-map values corresponding to Lucas numbers and then use k-Chebyshev maps to achieve consecutive and flexible key expansion and apply the pre-shared classical information between Alice and Bob and fountain codes for privacy amplification to solve the security of the exchange of classical information via the classical channel. Consequently, our high-capacity protocol does not have the limitations imposed by orbital angular momentum and down-conversion bandwidths, and it meets the requirements for longer distances and lower error rates simultaneously.

  2. High-capacity quantum key distribution using Chebyshev-map values corresponding to Lucas numbers coding

    Science.gov (United States)

    Lai, Hong; Orgun, Mehmet A.; Pieprzyk, Josef; Li, Jing; Luo, Mingxing; Xiao, Jinghua; Xiao, Fuyuan

    2016-11-01

    We propose an approach that achieves high-capacity quantum key distribution using Chebyshev-map values corresponding to Lucas numbers coding. In particular, we encode a key with the Chebyshev-map values corresponding to Lucas numbers and then use k-Chebyshev maps to achieve consecutive and flexible key expansion and apply the pre-shared classical information between Alice and Bob and fountain codes for privacy amplification to solve the security of the exchange of classical information via the classical channel. Consequently, our high-capacity protocol does not have the limitations imposed by orbital angular momentum and down-conversion bandwidths, and it meets the requirements for longer distances and lower error rates simultaneously.

  3. Optimizing Geographic Allotment of Photovoltaic Capacity in a Distributed Generation Setting: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Urquhart, B.; Sengupta, M.; Keller, J.

    2012-09-01

    A multi-objective optimization was performed to allocate 2MW of PV among four candidate sites on the island of Lanai such that energy was maximized and variability in the form of ramp rates was minimized. This resulted in an optimal solution set which provides a range of geographic allotment alternatives for the fixed PV capacity. Within the optimal set, a tradeoff between energy produced and variability experienced was found, whereby a decrease in variability always necessitates a simultaneous decrease in energy. A design point within the optimal set was selected for study which decreased extreme ramp rates by over 50% while only decreasing annual energy generation by 3% over the maximum generation allocation. To quantify the allotment mix selected, a metric was developed, called the ramp ratio, which compares ramping magnitude when all capacity is allotted to a single location to the aggregate ramping magnitude in a distributed scenario. The ramp ratio quantifies simultaneously how much smoothing a distributed scenario would experience over single site allotment and how much a single site is being under-utilized for its ability to reduce aggregate variability. This paper creates a framework for use by cities and municipal utilities to reduce variability impacts while planning for high penetration of PV on the distribution grid.

  4. Could the local population of the Lower Rhine delta supply the Roman army? Part 2: Modelling the carrying capacity of the delta using archaeological, palaeo-ecological and geomorphological data

    NARCIS (Netherlands)

    Kooistra, L.I.; van Dinter, M.; Dütting, M.K.; van Rijn, P.; Cavallo, C.

    2014-01-01

    In this part two of a diptych of articles, we modelled and quantified the carrying capacity of the landscape and the demand and supply of the Roman army in the western Lower Rhine delta with wood and food in the period A.D.  – . The absolute volumes of the wood and food were calculated (in m

  5. Environmental Carrying Capacity and Its Application in Environmental Impact Assessment of Industrial Park Planning%环境承载力及其在工业园区规划环境影响评价中的应用

    Institute of Scientific and Technical Information of China (English)

    路忠贤; 唐永顺

    2011-01-01

    环境承载力是可持续发展的理论基础,将环境承栽力理论应用到工业园区规划环境影响评价中,对协调区域社会经济发展和资源环境开发利用具有重要的意义。本文基于环境承载力的概念及内涵,在对环境承载力量化分析的基础上,建立一个专门针对工业园区的指标体系,以某工业园区规划环境影响评价为例,分析工业园区各规划期阶段的环境承载力的利用强度,以期为园区的可持续发展提供科学依据。%Environmental carrying capacity is the theoretical tbundation of sustainable development, and applying the theory of environmental carrying capacity to environmental impact assessment of industrial park planning is of great significance in coordinating regional socio - economic development and exploitation and utilization of resources. Based on the concept and connotation of environmental carrying capacity, a specific index system for industrial park is established on the basis of quantitative analysis of environmental carrying capacity. Then, an exmnple for industrial park planning environmental impact assessment was made, and environmental carrying capacity utilizing intensity of industrial park in each planning' stage is analyzed so as to provide scientific basis for sustainable development of industrial parks.

  6. Study on carrying capacity in Liaoning Province marine region by Fuzzy comprehensive evaluation%基于模糊综合评判的辽宁省海域承载力研究

    Institute of Scientific and Technical Information of China (English)

    曹可; 吴佳璐; 狄乾斌

    2012-01-01

    Based on the research results of carrying capacity,the carrying capacity in Liaoning Province marine was assessed by the fuzzy comprehensive evaluation method. The results showed the carrying capacity in Liaoning Province seawater is moderate between 1999 and 2009 except the year 2000. However, the figures always were between 0.34 and 0.40, which meant that the carrying capacity in Liaoning Province seawater was moderate by weak. The factors such as overfishing, large quantities of pollutants into the sea, ecological improvement and marine science and technology all contribute to the state of Liaoning Province seawater. Based on the analysis, the suggestions of improving the carrying capacity in Liaoning Province seawater were brought forward.%借鉴有关承载力的研究成果,利用模糊综合评判方法对辽宁省海域承载力进行了评价分析.结果表明:1999至2009年间,除2000年,辽宁省的海域承载力数值均处于适载范围,但是由于其数值绝大多数都在0.34 ~0.40之间浮动,因此辽宁省的海域承载能力为中等偏弱.过度捕捞、环境污染、环境治理能力和科技发展水平等因素的影响是辽宁省海域承载力中等偏弱的主要因素,基于此提出了改善辽宁省海域承载力的对策建议.

  7. Distributed Antenna Channels with Regenerative Relaying: Relay Selection and Asymptotic Capacity

    Directory of Open Access Journals (Sweden)

    Aitor del Coso

    2007-11-01

    Full Text Available Multiple-input-multiple-output (MIMO techniques have been widely proposed as a means to improve capacity and reliability of wireless channels, and have become the most promising technology for next generation networks. However, their practical deployment in current wireless devices is severely affected by antenna correlation, which reduces their impact on performance. One approach to solve this limitation is relaying diversity. In relay channels, a set of N wireless nodes aids a source-destination communication by relaying the source data, thus creating a distributed antenna array with uncorrelated path gains. In this paper, we study this multiple relay channel (MRC following a decode-and-forward (D&F strategy (i.e., regenerative forwarding, and derive its achievable rate under AWGN. A half-duplex constraint on relays is assumed, as well as distributed channel knowledge at both transmitter and receiver sides of the communication. For this channel, we obtain the optimum relay selection algorithm and the optimum power allocation within the network so that the transmission rate is maximized. Likewise, we bound the ergodic performance of the achievable rate and derive its asymptotic behavior in the number of relays. Results show that the achievable rate of regenerative MRC grows as the logarithm of the Lambert W function of the total number of relays, that is, 𝒞=log⁡2(W0(N. Therefore, D&F relaying, cannot achieve the capacity of actual MISO channels.

  8. Distributed Antenna Channels with Regenerative Relaying: Relay Selection and Asymptotic Capacity

    Directory of Open Access Journals (Sweden)

    del Coso Aitor

    2007-01-01

    Full Text Available Multiple-input-multiple-output (MIMO techniques have been widely proposed as a means to improve capacity and reliability of wireless channels, and have become the most promising technology for next generation networks. However, their practical deployment in current wireless devices is severely affected by antenna correlation, which reduces their impact on performance. One approach to solve this limitation is relaying diversity. In relay channels, a set of wireless nodes aids a source-destination communication by relaying the source data, thus creating a distributed antenna array with uncorrelated path gains. In this paper, we study this multiple relay channel (MRC following a decode-and-forward (D&F strategy (i.e., regenerative forwarding, and derive its achievable rate under AWGN. A half-duplex constraint on relays is assumed, as well as distributed channel knowledge at both transmitter and receiver sides of the communication. For this channel, we obtain the optimum relay selection algorithm and the optimum power allocation within the network so that the transmission rate is maximized. Likewise, we bound the ergodic performance of the achievable rate and derive its asymptotic behavior in the number of relays. Results show that the achievable rate of regenerative MRC grows as the logarithm of the Lambert W function of the total number of relays, that is, . Therefore, D&F relaying, cannot achieve the capacity of actual MISO channels.

  9. ORIGINATION AND DEVELOPMENT OF THE CONCEPT OF AQUATIC ECOLOGICAL CARRYING CAPACITY IN THE BASIN%流域水生态承载力研究的起源和发展

    Institute of Scientific and Technical Information of China (English)

    曾晨; 刘艳芳; 张万顺; 汤弟伟

    2011-01-01

    流域水生态承载力的研究是近几年来从水生态的角度解决流域可持续发展问题的有效手段.通过文献综述的方法,从流域水生态承载力的起源和发展入手,对流域水生态承载力的理论基础,与相关已有研究的区别和联系进行了探讨,并对流域水生态承载力的进一步研究进行了展望.从起源上看,承载力理论、可持续发展和生态足迹理论、流域生态学理论分别是流域水生态承载力研究的基础、落脚点和支撑.从发展上看,水生态承载力是水资源和水环境承载力的有机结合和深化.从测度和评价方法上看,第一生产者的净初级生产力方法,生态足迹法、可持续发展指标法和生态系统健康等生态承载力的测度方法为流域水生态承载力的评价奠定了基础.目前流域水生态承载力的研究尚处于初级阶段,今后不论是在理论探讨还是模型应用中均应进一步体现人类与自然和谐共存的根本目的以及水体质、量辩证统一的规律,通过物质、能量、信息、空间和时间五位一体的研究方法,使流域水生态承载力的研究更具有实践意义.%Research on the watershed ecological carrying capacity is an effective measure of settling sustainable development problem at basin scale from the perspective of water ecology in recent years. Through reviewing on previous literature, the origination and development of aquatic ecological carrying capacity in the basin are discussed;the theoretical foundation and previous related research are investigated;the further research is forecasted. Originally,the theory of carrying capacity is the foundation of the research;the theory of sustainable development and ecological footprint are the objectives; the theory of watershed ecology is the support. In the research progress, water ecological carrying capacity is the dynamic integration and deepening of water resource and environment carrying capacity

  10. Characterizing corridor-level travel time distributions based on stochastic flows and segment capacities

    Directory of Open Access Journals (Sweden)

    Hao Lei

    2015-12-01

    Full Text Available Trip travel time reliability is an important measure of transportation system performance and a key factor affecting travelers’ choices. This paper explores a method for estimating travel time distributions for corridors that contain multiple bottlenecks. A set of analytical equations are used to calculate the number of queued vehicles ahead of a probe vehicle and further capture many important factors affecting travel times: the prevailing congestion level, queue discharge rates at the bottlenecks, and flow rates associated with merges and diverges. Based on multiple random scenarios and a vector of arrival times, the lane-by-lane delay at each bottleneck along the corridor is recursively estimated to produce a route-level travel time distribution. The model incorporates stochastic variations of bottleneck capacity and demand and explains the travel time correlations between sequential links. Its data needs are the entering and exiting flow rates and a sense of the lane-by-lane distribution of traffic at each bottleneck. A detailed vehicle trajectory data-set from the Next Generation SIMulation (NGSIM project has been used to verify that the estimated distributions are valid, and the sources of estimation error are examined.

  11. Conditions of Proper Interaction of Low-Pressure Injection Piles (LIP) with Structure and Soil, Carrying Capacity of Pile Anchorage in Foundation

    Science.gov (United States)

    Pachla, Henryk

    2016-12-01

    The formation of a pile in the existing foundation and soil creates a new foundation construction which has a structure of foundation-pile-soil. This construction must be able to transfer loads from the foundation to the pile and from the pile to the soil. The pile structure has to transfer an imposed load. From the point of view of continuum mechanics determination of the capacity of such a system is preceded by the analysis of contact problem of three contact surfaces. Each of these surfaces is determined by different pairs of materials. The pair which creates a pile anchorage is a material from which the foundation is built (structure of stone and grout, brick and grout, concrete or reinforced concrete and grout. The pile structure is formed by grout and steel rebar. The pile formed in soil is created by a pair of grout and soil. What is important is that on contact surfaces the materials adhering to one another are subjected to different deformation types that are controlled by mechanical properties and geometry of these surfaces. In the paper, additional conditions that should be fulfilled for the foundation-pile-soil system to make load transfer from foundation to soil possible and safe are presented. The results of research done by the author on foundation-pile contact surface are discussed. The tests were targeted at verifying the bearing capacity of anchorage and deformation of piles made of grout and other materials from which foundations are built. The specimens were tested in tension and compression. The experiments were conducted on the amount specimens which is regarded as small sample to enable the statistical analysis of the results.

  12. Spatial Structure Evolution of Urban System in the Loess Plateau Based on Ecological Carrying Capacity -A Case Study in Qingyang City%基于生态承载力的黄土高原地区城镇系空间结构演化——以庆阳市为例

    Institute of Scientific and Technical Information of China (English)

    刘海龙; 石培基; 张学斌; 张惠; 魏伟

    2013-01-01

    庆阳市位于黄土高原中部丘陵沟壑区,气候干旱,生态脆弱.运用生态承载力、城镇体系相关理论和方法,分析研究区城镇体系空间结构演化特点及趋势.采用生态弹性度、资源承载力和承载压力度、对生态承载力的演化进行综合评价,并对生态承载力与城镇空间结构的关系进行探讨.在此基础上,对研究区城镇体系空间结构进行调整优化,为脆弱生态条件下的城镇发展提供依据.%Qingyang City is located in a hilly-gully region in the central Loess Plateau,it is arid,and the ecological environment is fragile.In this paper,the spatial structure evolution of urban system in the study area was analyzed based on the ecological carrying capacity.The results showed that there was a traffic directivity in the study area during the period of 1985-2010,and the town development was restricted by the limited traffic conditions.Urban distribution was related to the distribution of water resources,and it was different from different counties.Double center pattern was gradually formed under the optimization of urban system.The ecological elastic degree,carrying capacity of resources and load pressure strength were used in the evaluation.The results showed that the ecological elastic degree and carrying capacity of resources in the study area were holistically in an ascendant trend during the period of 1985-2010.Spatial structure of the regional urban system and the ecological carrying capacity interacted,and the relationship between the ecological carrying capacity and the spatial structure of urban system was discussed.Some measures were proposed for optimizing the spatial structure of urban system in the study area based on the ecological carrying capacity in such fragile ecological environment.

  13. Yeast NDI1 Improve Oxidative Phosphorylation Capacity and Increases Protection Against Oxidative Stress and Cell Death in Cells Carrying a Leber’s Hereditary Optic Neuropathy Mutation

    OpenAIRE

    Park, Jeong Soon; Li, You-Fen; Bai, Yidong

    2007-01-01

    G11778A in the subunit ND4 gene of NADH dehydrogenase complex is the most common primary mutation found in Leber’s hereditary optic neuropathy (LHON) patients. The NDI1 gene, which encodes the internal NADH -quinone oxidoreductase in Saccharomyces cerevisiae, was introduced into the nuclear genome of a mitochondrial defective human cell line, Le1.3.1, carrying the G11778A mutation. In transformant cell lines, LeNDI1-1 and -2, total and complex I-dependent respiration were fully restored and l...

  14. Integration of Electric Vehicles into the Power Distribution Network with a Modified Capacity Allocation Mechanism

    Directory of Open Access Journals (Sweden)

    Junjie Hu

    2017-02-01

    Full Text Available The growing penetration of electric vehicles (EVs represents an operational challenge to system operators, mainly at the distribution level by introducing congestion and voltage drop problems. To solve these potential problems, a two-level coordination approach is proposed in this study. An aggregation entity, i.e., an EV virtual power plant (EV-VPP, is used to facilitate the interaction between the distribution system operator (DSO and EV owners considering the decentralized electricity market structure. In level I, to prevent the line congestion and voltage drop problems, the EV-VPP internally respects the line and voltage constraints when making optimal charging schedules. In level II, to avoid power transformer congestion problems, this paper investigates three different coordination mechanisms, or power transformer capacity allocation mechanisms, between the DSO and the EV-VPPs, considering the case of EVs charging and discharging. The three mechanisms include: (1 a market-based approach; (2 a pro-rata approach; and (3 a newly-proposed constrained market-based approach. A case study considering a 37-bus distribution network and high penetration of electric vehicles is presented to demonstrate the effectiveness of the proposed coordination mechanism, comparing with the existing ones.

  15. 基于数学模型的物流港口资源承载能力预测%Forecasting of Resource Carrying Capacity of Logistics Terminals Based on Mathematical Model

    Institute of Scientific and Technical Information of China (English)

    陈朝坚

    2014-01-01

    In this paper, we built the mathematical model of the resource carrying capacity of logistics terminals, then comprehensively forecast the transportation resource carrying capacity of the Qinhuangdao logistics terminal to verify the correctness of the mathematical model and presented the scientific planning for the future construction of the terminal.%建立了物流港口资源承载能力的数学模型,对港口交通资源承载力进行了综合预测预警,以河北省秦皇岛物流港口为例,验证了数学模型的正确性,并对秦皇岛港口未来的港口建设提出了科学的规划。

  16. Could the local population of the Lower Rhine delta supply the Roman army? Part 2: Modelling the carrying capacity of the delta using archaeological, palaeo-ecological and geomorphological data

    NARCIS (Netherlands)

    Kooistra, L.I.; van Dinter, M.; Dütting, M.K.; van Rijn, P.; Cavallo, C.

    2014-01-01

    In this part two of a diptych of articles, we modelled and quantified the carrying capacity of the landscape and the demand and supply of the Roman army in the western Lower Rhine delta with wood and food in the period A.D.  – . The absolute volumes of the wood and food were calculated (in m a

  17. On the MIMO Capacity for Distributed System under Composite Rayleigh/Rician Fading and Shadowing

    Directory of Open Access Journals (Sweden)

    Santiago González-Aurioles

    2015-01-01

    Full Text Available Wireless channels are commonly affected by short-term fading and long-term fading (shadowing. The shadowing effects must be taken into account also when mobility is present in the wireless scenario. Using a composite fading model, the total channel capacity can be studied for a scenario with short-term Rayleigh fading along with shadowing. This work provides quantitative results for these kinds of scenarios with Rayleigh fading and shadowing, considering also multiple-input and multiple-output systems, which have not been previously reported. In addition, the channel capacity has been studied in depth in its relation with the shadowing level, signal to noise ratio, and the number of elements in the multiple-input and multiple-output system. Moreover, the channel performance with shadowing has been compared to the one without it. Furthermore, Rician model with shadowing is studied and its results are reported. In addition, correlated and experimental results are provided. It is identified that the distributed MIMO systems can benefit from shadowing in Rician channels. This advantage has not been reported previously. This type of fading is proposed for massive MIMO by others and our results open the door to emulate massive MIMO on a reverberation chamber.

  18. Critical capacity, travel time delays and travel time distribution of rapid mass transit systems

    Science.gov (United States)

    Legara, Erika Fille; Monterola, Christopher; Lee, Kee Khoon; Hung, Gih Guang

    2014-07-01

    We set up a mechanistic agent-based model of a rapid mass transit system. Using empirical data from Singapore's unidentifiable smart fare card, we validate our model by reconstructing actual travel demand and duration of travel statistics. We subsequently use this model to investigate two phenomena that are known to significantly affect the dynamics within the RTS: (1) overloading in trains and (2) overcrowding in the RTS platform. We demonstrate that by varying the loading capacity of trains, a tipping point emerges at which an exponential increase in the duration of travel time delays is observed. We also probe the impact on the rail system dynamics of three types of passenger growth distribution across stations: (i) Dirac delta, (ii) uniform and (iii) geometric, which is reminiscent of the effect of land use on transport. Under the assumption of a fixed loading capacity, we demonstrate the dependence of a given origin-destination (OD) pair on the flow volume of commuters in station platforms.

  19. Dynamic plantar pressure distribution, strength capacity and postural control after Lisfranc fracture-dislocation

    DEFF Research Database (Denmark)

    Mehlhorn, Alexander T; Walther, Markus; Yilmaz, Tayfun

    2017-01-01

    of life. 17 consecutive patients suffering from a Lisfranc fracture dislocation were registered, underwent open reduction and internal fixation and were followed-up for 50.5±25.7months (Mean±SDM). Biomechanical analysis of muscle strength capacities, postural control and plantar pressure distribution...... correlated well with clinical outcome. Altered postural control was evident by a significant reduction in unilateral stance time, from which we calculated a strong correlation between stance time and the isokinetic strength measurement. Plantar pressure measurements revealed a significant reduction in peak...... pressure under the midfoot and of Force-Time Integral beneath the second metatarsal. Sufficient rehabilitation is crucial to the clinical outcome following anatomical open reduction of Lisfranc fracture-dislocation. The present study supports a rehabilitation approach focussing on restoring proprioception...

  20. Deployment Strategy for Charging Piles Based on Distribution Network Capacity Planning and Users’ Needs

    Directory of Open Access Journals (Sweden)

    Du Chongyang

    2015-01-01

    Full Text Available Electric vehicles are the most potential transports in the future. However, the large scale of charging facilities will make a great influence on gird. There is a need to make a research on the construction of charging facilities. Based on the power demand characteristics of electric vehicle charging, distribution network capacity, charging system performance and other aspects, this paper mainly researched the deployment strategy of charging piles. First, the authors built up a model with characteristics of charging power demand of electric vehicle and a model of charging service system. The characteristic of daily load curve is analyzed. Second, based on these works, the authors designed the progress of strategy making. At last, the progress was verified by the actual use case.

  1. Research on Forewarning System of Tourism Carrying Capacity in Pingtan Island Based on Fuzzy Comprehensive Evaluation%基于模糊综合评价的海岛旅游环境承载力预警研究

    Institute of Scientific and Technical Information of China (English)

    戴丽芳; 丁丽英

    2012-01-01

    以旅游环境承栽力预警相关理论为指导,采用定性和定量相结合的方法,建立旅游环境承栽力综合评价指标体系,并以平潭海岛为个案进行实证研究.结果表明:平潭旅游环境承栽力总体处于轻度超栽状态,为实现平潭旅游的可持续发展,提出了平潭旅游今后发展的重点方向.%This paper is using the process of qualitative and quantitative combination to build the tourism carrying capacity assessment criteria system under the guidance of the forewarning system of the tourism carrying capacity and based on the empirical research of Pingtan Island. The results show that. the overall tourism carrying capacity in Pingtan is slightly overloaded. In order to achieve the sustainable development of tourism in Pingtan,the paper presents key directions of its furture development.

  2. Water Environmental Carrying Capacity in Shaanxi Province Based on Vector Norm Method%基于向量模法的陕西省水环境承载力评价

    Institute of Scientific and Technical Information of China (English)

    张军

    2012-01-01

    Evaluation index of water environmental carrying capacity in Shaanxi is determined, depending on characteristics of the water environment in Shaanxi Province and selection principles of water environment carrying capacity evaluation index. Vector norm method is used to determined normalized value of each index of the various types of evaluation factors,based on analysis of the vector-mode method characteristics. The study results show that water environmental carrying capacity in Shaanxi Province improved gradually from 2005 to 2009 and the valuation value rose from 0.281 to 0.352.%根据陕西省水环境特征和水环境承载力评价指标的选取原则确定了陕西省水环境承载力评价指标.在分析向量模法特征的基础上,应用向量模法确立了各类评价因素的每个因子的归一化值.得出陕西省水环境承载力状态结果,结果表明2005-2009年间陕西省水环境承载力状况呈逐年改善的趋势,水环境承载力评价值由0.281升至0.352.

  3. Computing System Construction of Water Environment Carrying Capacity in Huaihe River Basin%淮河流域水环境承载能力计算系统的构建

    Institute of Scientific and Technical Information of China (English)

    严子奇; 夏军; 左其亭; 张永勇

    2009-01-01

    本文介绍了淮河流域水环境承载能力计算系统的总体设计、承载力数学模型的建立、软件系统的结构及应用.研究中通过计算在维系"良好水环境状况"目标下流域所能承载的社会经济规模上限来得到流域水环境承载能力.在耦合了社会经济系统模型、水资源转化关系模型、水环境系统模拟模型的基础上利用数据库、地理信息系统、可视化编程技术将"社会经济-水资源-水环境"系统模型、生态需水量计算模型、以及水环境承载能力计量模型中众多的边界条件、控制条件、可变参数及成果分析进行系统集成.所建立的淮河流域水环境承载能力计算系统可有效地实现流域现状水环境承裁能力的计算以及对未来不同时刻、不同频率来水条件下的承载力进行情景分析计算,为流域水环境承载能力管理提供决策支持.%In this paper, the overall designs and mathematical model of water environment carrying capacity, as well as the system structure and application of water environment carrying capacity computing system in Huaihe River Basin are presented. The carrying capacity of water environment in river basin is reached by calculating the upper limit of the socio-economic scale that watershed can carry under the "good status of water environment". The system is based on an integrated "socio-economic-water resource-water environment" model which is coupled with the socio-economic system model, the water resource transformation relation model and the simulation model of water environment system. The population size is a key indicator to reflect the water environment carrying capacity of the basin, and iterative algorithm is used to get the maximum population size of different water environment carrying capacities. This system also contains a subroutine for ecological water requirement model. The mean value of the results from the Tennant method, base flow method and

  4. 红寺堡生态脆弱移民区水资源承载力分析%An Analysis of Water Resources Carrying Capacity in Vulnerable Ecological Immigration Area in Hongsipu

    Institute of Scientific and Technical Information of China (English)

    贾科利; 郭慧秀

    2015-01-01

    Taking the vulnerable ecological immigration area in Hongsipu as an example, an evaluation indicator system of water resources carrying capacity is constructed from the aspects of water resources system,economic system,social system and ecological system. A comprehensive evaluation and analysis were conducted on the water resources carrying capacity of the area in 2014 and the GDP of the area in 2020 was estimated by the method of non-linear regression and the popula-tion of the area was also estimated by the method of Markov mode. The results showed that the population and economic development are within the carrying capacity of the water resources in Hongsipu district in the present stage and the water resources are not in overloaded state. In 2020,the economic development will be within the carrying capacity of water re-sources,but the population will overload seriously,and the pressure of the water resources carrying capacity will gradually increase.%以红寺堡生态脆弱移民区为例,从社会系统、经济系统、生态系统和水资源系统构建水资源承载力评价指标体系,对该区2014年水资源承载力状况进行综合评价分析,并采用非线性回归法和马尔科夫预测模型分别对该区2020年GDP和人口进行估测。结果表明,现阶段红寺堡区经济、人口总体上可载,水资源未出现超载状态,而到2020年社会经济发展总体可载,但人口超载严重,水资源承载压力逐渐增大。

  5. Islamic Economic System, Poverty and Insurgency: From Zakāh Distribution to Capacity Building

    Directory of Open Access Journals (Sweden)

    Mahmud Adesina Ayuba

    2016-12-01

    Full Text Available Previous studies on Zakāh administration have addressed the issue of distribution of Zakāh funds to reduce the sufferings of the poor. The purpose of this work, however, is to argue for a change from Zakāh distribution to capacity building approach so as to change the condition of the poor and the needy from being Zakāh recipients to Zakāh payers. The fact remains that Nigeria is a rich nation but its people are poor. Many factors have been adduced to be the causes of poverty and perennial insurgency in Nigeria. It is observed that Zakāh is not administered as it ought in Nigeria. The study proffered efficient Zakāh institution as an effective antidote to curb the menace of poverty and insecurity. The paper argues through poverty alleviation model that if Zakāh is properly managed and disbursed judiciously, many destitute would be saved from the cloak of unscrupulous politicians and half-baked scholars who use them to destabilize the country. The study also believed that if Zakāh authority could be sending the poor to training centers to gain certain skills or financing their children’s education; this would improve their living condition. The study utilized historical and ideological framework, while relying on secondary sources.

  6. 基于开发区规划环评的土地资源承载力评价%Evaluation of land resources carrying capacity of development zone based on planning environment impact assessment

    Institute of Scientific and Technical Information of China (English)

    傅世锋; 张平; 蒋金龙

    2012-01-01

    Assessment of land resources carrying capacity is the key point of planning environment impact assessment and the main foundation to determine whether the planning could be implemented or not. With the help of the space analysis function of Geographic Information System, and selecting altitude, slope, land use type, distance from resident land, distance from main traffic roads, and distance from environmentally sensitive area as the sensitive factors, a comprehensive assessment on the ecological sensitivity and its spatial distribution in Zhangzhou Merchants Economic and Technological Development Zone, Fujian Province of East China was conducted, and the assessment results were combined with the planning land layout diagram for the ecological suitability analysis. In the Development Zone, 84.0% of resident land, 93. 1% of industrial land, 86.0% of traffic land, and 76. 0% of other constructive lands in planning were located in insensitive and gently sensitive areas, and thus, the implement of the land use planning generally had little impact on the ecological environment, and the land resources in the planning area was able to meet the land use demand. The assessment of the population carrying capacity with ecological land as the limiting factor indicated that in considering the highly sensitive area and 60% of the moderately sensitive area as ecological land, the population within the Zone in the planning could reach 240000, and the available land area per capita could be 134. 0 m2. Such a planned population scale is appropriate, according to the related standards of constructive land.%土地资源承载力评价是规划环境影响评价的重点,是决定规划是否可以实施的重要依据.基于地理信息系统技术的空间分析功能,选取高程、坡度、土地利用现状、距居民点距离、距主要交通道路距离和距环境敏感区距离作为敏感因子,综合评价了漳州招商局经济技术开发区生态敏感性程度及其

  7. Analysis on Environmental Carrying Capacity in Planning Environmental Impact Assessment of Qunli%群力新区规划环境影响评价中的环境承载力分析

    Institute of Scientific and Technical Information of China (English)

    王博; 付宁

    2012-01-01

    As the core element of planning environmental impact assessment,environmental carrying capacity analysis can characterize the environmental comprehensive impacts of projects from the view of whole system based on the environmental carrying capacity threshold.Its fundamental purpose is to determine whether the project planning suits the bearing capacity of the region's resources.Ultimately,it is to solve the coordinated development of regional socio-economic and environmental resource development issues.Taking the environmental impact assessment of Qunli District as example,this study establishes a comprehensive environmental indicator system and provides detailed description of general content,methods and other aspects of environmental carrying capacity analysis.%环境承载力分析作为规划环境影响评价中核心内容之一,可以在环境承载能力阈值的基础上真实地度量并以系统的观点表达一项规划对环境的综合影响程度,其根本目的在于确定规划开发强度能否与该地区资源环境承载力相协调,归根结底是解决区域社会经济与资源环境协调发展的问题。以群力新区规划环境影响评价为研究实例,建立群力新区的综合环境承载力指标体系,详细地阐述了环境承载力分析的一般内容、方法等方面的内容。

  8. Study on ecological carrying capacity in Shanghai based on sustainable development%基于可持续发展的上海市生态承载力研究

    Institute of Scientific and Technical Information of China (English)

    王瑶

    2016-01-01

    A comprehensive evaluation system of ecological carrying capacity has been constructed from four aspects which include economic development,social progress,energy and resource utilization,en-vironmental quality. Index weights are determined by Coefficient of Variation,the ecological carrying capacity of shanghai from 2003 to 2010 has been calculated by Fuzzy Comprehensive Evaluation. The research shows that:The development of Shanghai shows a good momentum,the sustainable develop-ment capacity is constantly growing,and the ecological carrying capacity is constantly improving,how-ever,the coordination of social declines. We need adjust industrial structure for further,solve urban management issues posed by overpopulation. and improve the degree of social coordination.%从经济发展、社会进步、能源和资源利用、环境质量方面,构建上海市生态承载力评价指标体系,采用变异系数法确定指标权重,运用模糊综合评价法,研究上海市2003~2013年生态承载力.研究表明:上海市经济发展呈现良好态势,可持续发展能力不断增强,生态承载力不断提高,但社会协调度下降,需要进一步调整产业结构,解决人口过多所带来的城市管理问题,提高社会协调度.

  9. DESIGN OF STRUCTURAL ELEMENTS IN THE EVENT OF THE PRE-SET RELIABILITY, REGULAR LOAD AND BEARING CAPACITY DISTRIBUTION

    Directory of Open Access Journals (Sweden)

    Tamrazyan Ashot Georgievich

    2012-10-01

    Full Text Available Accurate and adequate description of external influences and of the bearing capacity of the structural material requires the employment of the probability theory methods. In this regard, the characteristic that describes the probability of failure-free operation is required. The characteristic of reliability means that the maximum stress caused by the action of the load will not exceed the bearing capacity. In this paper, the author presents a solution to the problem of calculation of structures, namely, the identification of reliability of pre-set design parameters, in particular, cross-sectional dimensions. If the load distribution pattern is available, employment of the regularities of distributed functions make it possible to find the pattern of distribution of maximum stresses over the structure. Similarly, we can proceed to the design of structures of pre-set rigidity, reliability and stability in the case of regular load distribution. We consider the element of design (a monolithic concrete slab, maximum stress S which depends linearly on load q. Within a pre-set period of time, the probability will not exceed the values according to the Poisson law. The analysis demonstrates that the variability of the bearing capacity produces a stronger effect on relative sizes of cross sections of a slab than the variability of loads. It is therefore particularly important to reduce the coefficient of variation of the load capacity. One of the methods contemplates the truncation of the bearing capacity distribution by pre-culling the construction material.

  10. Calculation method of livestock carrying capacity of irrigation forage grassland in arid area%干旱区灌溉饲草料地载畜量计算方法

    Institute of Scientific and Technical Information of China (English)

    廖梓龙; 魏永富; 郭中小; 徐晓民; 龙胤慧; 宋一凡

    2014-01-01

    Water is the key factor to in management of grassland and livestock balance in arid area. The effective way of management is to achieve a balance of supply and demand for water forage grass and livestock. This balance consists of three parts:forecasting the forage grass yield by the water balance theory, planning the livestock carrying capacity related to the forage grass intake and drinking water consume, and estimating the optimal number of livestock husbandry under the coupled limitation of the available forage grass intake carrying capacity and the available water resources quantity. There are some inaccuracy problem in applying traditional carrying capacity calculation method, such as the yield forecasting of forage grass and livestock intake feeding. The objective of this paper was to build a new livestock carrying capacity calculation model based on water-grass-livestock balance. Using Damao county in Inner Mongolia Autonomous Region as research area, we analyzed the curve of water productivity under the different rainfall and irrigation conditions, and forecasted the yield of silage corn by water productivity curve. The irrigation experiment of silage corn under different water condition and different precipitation revealed that there was a non-linear relationship between the water productivity and the sum of precipitation and irrigation. Increasing the sum of precipitation and irrigation can promote the water productivity, but excessive supplying from precipitation and irrigation may lead to a reduction of crop water use efficiency. Based on analyzing the curve of water productivity, the experiment result suggested that the highest water productivity was 12.42 kg/m3 water which achieved with 550 mm water from both precipitation and irrigation. Precipitation was the vital limited factor for silage corn yield. The calculated silage corn yield of humid, medium and arid scenario was 6.83 kg/m2, 5.25 kg/m2, 3.47 kg/m2 respectively. For livestock intake feeding

  11. Influence of low molecular weight fractions of humic substances on reducing capacities and distribution of redox functional groups

    Science.gov (United States)

    Yang, Zhen; Jiang, Jie

    2016-04-01

    Humic substances (HS) are redox-active organic compounds and their reducing capacities depend on their molecule structure and distribution of redox functional groups (RFG). During dialysis experiments, bulk humic acids (HA) were separated into low molecular weight fractions (LMWF) and retentate. LMWF account for only 2% of the total organic carbon content of HA molecules, however, their reducing capacities are up to 33 times greater than either those of the bulk HA or retentate. Furthermore, the total reducing capacity of the bulk HA accounts for less than 15% of the total reducing capacity of bulk HA, retentate and LMWF combined, suggesting that releasing of LMWF cannot reduce the number of RFG. RFG are neither in fixed amounts nor in uniformly distributed in bulk HA. LWMF have great fluorescence intensities for humic-like fluorophores (quinone-like functional groups), where quinonoid π-π* transition is responsible for the great reducing capacities of LMWF, and protein-like fluorophores. The 3,500 Da molecules (1.25 nm diameter) of HS could stimulate transformation of redox-active metals or potential pollutants trapped in soil micropores (< 2 nm diameter). A development of relationship between reducing capacity and Ex/Em position provides a possibility to predicate relative reducing capacities of HS in environmental samples.

  12. Ecological Footprint and Ecological Carrying Capacity of Water Resources in Henan Province%河南省水资源生态足迹和生态承载力分析

    Institute of Scientific and Technical Information of China (English)

    卢艳; 于鲁冀; 王燕鹏; 王振波

    2011-01-01

    Previous literatures about ecological footprint and ecological carrying capacity of water resources have little focused on ecological accounting classification of water resources and its equivalence factor and yield factor so that few work on ecological footprint of water resources are satisfactory.Water resources accounting are classified and region equivalence factor and yield factor present in this paper to calculate ecological footprint and ecological carrying capacity of water resources in Henan province by using data in 2007.The results showed that there was an ecological deficit in water resources in most cities of Henan province, but there existed spatial difference not only in ecological footprint and ecological carrying capacity but also in ecological footprint and ecological carrying capacity per capita with great ecological deficit in most of regions.In ecological footprint accounting composition of water resources, ecological footprint of agricultural-forest-fishing was dominant.In ecological capacity accounting composition of water resources,ecological capacity of underground water resource was primary in the south and west of Henan province, but ecological carrying capacity of surface water resource was primary in the north of Henan province.%在水资源生态足迹研究过程中,存在的主要问题是:忽略了对水资源帐户的划分,全球及地区水资源生态均衡因子和产量因子的确定,在实际应用中缺乏对水资源生态足迹和生态承载力的核算.笔者对水资源帐户进行了划分,并计算了地区水资源生态均衡因子和产量因子,以河南省为研究范围核算了2007年水资源生态足迹和生态承载力,结果表明:河南省多数城市水资源呈现生态赤字,同时不仅水资源生态足迹和生态承载力存在着空间差异,而且人均水资源生态足迹和生态承载力也存在着空间分布的不均衡性.水资源生态足迹与生态承载力帐户分解研究结果

  13. Standards for the Estimation of Tourism Carrying Capacity of Countryside Wetland Parks%郊野湿地公园旅游环境容量测算标准构建

    Institute of Scientific and Technical Information of China (English)

    张桦; 储九志

    2013-01-01

    Based on differences among geographic locations, Wetland Parks were divided into 3 types of city, suburban and countryside. A special function of the countryside wetland parks is tourism support. By reviewing the first batch of National Wetland Parks and taking into account of results from relevant studies, an indicators system for the tourism capacity of countryside wetland parks was developed. Standards for estimating the tourism carrying capacity was developed by integrating other relevant standards through questionnaires. The standards covers carrying capacities in 5 major aspects: ecology, resources, psychological, facilities and management capacity, including a total of 18 elements. The standards provided a good foundation for further studies.%基于地理位置差异将湿地公园分为城市、城郊与郊野3类,探讨郊野湿地公园承担旅游功能所具有的特殊性,通过对首批国家湿地公园的梳理,结合相关研究成果,提出郊野湿地公园旅游环境容量测算的指标体系,在此基础上采用相关标准指标,通过问卷调研等方法构建其测算标准.测算标准包括旅游环境容量中的生态、资源、心理、设施及管理5大容量,共计18项因子,为其测算研究提供良好基础.

  14. 重庆市水资源生态足迹与生态承载力分析%Analysis of Water Resources Ecological Footprint and Ecological Carrying Capacity in Chongqing City

    Institute of Scientific and Technical Information of China (English)

    王文国; 龚久平; 青鹏; 潘科; 胡启春

    2011-01-01

    利用水资源生态足迹分析方法对重庆市2000~2009年的水资源生态足迹、生态承载力进行了分析.重庆市历年水资源承载力大于水资源生态足迹,存在一定的生态盈余,水资源生态承载力受干旱等自然灾害影响较大.重庆市水资源生态足迹在逐年提高,万元国内生产总值水资源生态足迹在逐年下降,水资源开发利用程度和利用效率逐步提高.重点讨论了水资源生态足迹在三次产业间和城乡间的差异.%According to the calculation model of water resources ecological footprint, the water resources ecological footprint and ecological carrying capacity in the years from 2000 to 2009 in Chongqing City were analyzed.The results showed that the water resources carrying capacity were more than the water resources ecological footprint in the nine years in Chongqing, the ecological surplus was existed.On the other hand, water resources ecological carrying capacity was impacted by drought.The water resources ecological footprint of Chongqing increased in the pasted nine years,while the water resources ecological footprint per 104 Yuan GDP continued to decrease.This indicated that the utilization of water resources in Chongqing gradually increased in the pasted years.The differences among the primary industry,secondary industry and tertiary industry, and between urban and rural areas in Chongqing City were discussed.

  15. Evaluation of Marine Resource Carrying Capacity in the Construction of Qingdao Blue Economy Zone%青岛市蓝色经济区建设的海洋资源承载力评价

    Institute of Scientific and Technical Information of China (English)

    李京梅; 许玲

    2013-01-01

    From the standpoints of marine resources supply and marine industry demands ,this article built a comprehensive evaluation indicator system and measured marine resource carrying capacity in Qing-dao from 2001 to 2010 by the fuzzy comprehensive evaluation method .The results showed that the devel-opment of marine industry was beyond the marine resource carrying capacity in 2001 to 2006 and 2008 ,and was within the carrying capacity in the rest three years .The construction of the seaports has increased the supply ability of marine resources to some extent ,but the pollution caused by traditional marine industries is still huge ,and is a major cause for the bad performance of marine resource carrying capacity .It is sug-gested that traditional aquaculture should be reformed ,and environment friendly industries like recreation fishery and tourism should be developed in the process of constructing the blue economy zone .%从胶州湾海域资源环境供给和青岛市海洋产业增长需求的角度,构建了青岛市海洋资源承载力综合评价指标体系,利用模糊综合评价方法,对青岛市2001-2010年间海洋资源承载状况进行测度。结果表明,2001-2006年及2008年青岛市海洋资源承载力处于超载状态,其余年份处于适载状态。海岸带开发的港口建设在一定程度上提高了海洋资源的供给能力,但传统海洋产业的排污需求依然较大,是海洋资源承载力超载的重要原因。建议在蓝色经济区建设中,加快对传统养殖业的改造,大力发展休闲渔业、滨海旅游业等能耗低、排污少的产业。

  16. 基于熵权法及灰色关联模型的水资源承载力研究%Research on carrying capacity of water resources based on entropy-weight and grey-correlation model

    Institute of Scientific and Technical Information of China (English)

    朱玲燕; 苏维词

    2014-01-01

    The evaluation of carrying capacity of water resources is an important mean to judge whether the water resources of a city is safe.Taking Quzhou city as the research object , the paper chose the main indexes of carrying capacity evaluation of water resources by grey correlation model.It calculated the total value of water resources carrying capacity and the weight by use of entropy-weight method. Results indi-cate that①the weights of sewage treatment rate and water consumption per ten thousand yuan GDP are 0.1719 and 0.1261 respectively,which are the main indexes of water resources carrying capacity evalua-tion.②The total value of water resources of Quzhou had been raising gradually from 2004 to 2011 .In 2010, the value reached the highest which is about that of 1.23 times in 2004.The paper analyzed the status of water resources in Quzhou and propsed some suggestion for the sustainable utilization of water re-sources.%水资源承载力评价是判断一个城市水资源是否安全的重要手段。本文以衢州市为研究对象,通过应用灰色关联模型选取反映水资源承载力的主要指标,并利用熵权法计算指标权重和水资源承载力综合得分。计算结果表明:①衢州市水资源承载力主要影响指标污水处理率、万元GDP耗水量的权重分别是0.1719,0.1261。②2004-2011年,衢州市水资源承载力综合得分呈上升趋势,特别是2010年达到最高值,约为2004年的1.23倍。本文通过分析衢州市水资源利用状况,提出可持续利用水资源的建议。

  17. Enhancing the Capacity of the AC Distribution System Using DC Interlinks - A Step Towards Future DC Grid

    DEFF Research Database (Denmark)

    Chaudhary, Sanjay; Guerrero, Josep M.; Teodorescu, Remus

    2015-01-01

    The development of distributed generation system and electric vehicles is bound to strain the distribution network. A typical radial distribution feeder suffers from the voltage fluctuation and feeder overload in the presence of a large amount of variable renewable generation. This paper presents...... a concept of enhancing the power handling capacity of distribution networks using dc grid interconnections. Control of both the active and reactive power exchange between the ac feeder and the interconnecting power converter has been proposed for the voltage regulation at the ac feeder terminal. Besides...

  18. Social Carrying Capacity as Status Group Convention.

    Science.gov (United States)

    West, Patrick C.

    A sociological study investigating the relationship between perception of crowding and social status was conducted in a rural camping setting. Results indicate that higher social status groups and groups aspiring to higher social status are more likely to perceive crowding than are lower status groups, but more research is suggested prior to the…

  19. Social Carrying Capacity as Status Group Convention.

    Science.gov (United States)

    West, Patrick C.

    A sociological study investigating the relationship between perception of crowding and social status was conducted in a rural camping setting. Results indicate that higher social status groups and groups aspiring to higher social status are more likely to perceive crowding than are lower status groups, but more research is suggested prior to the…

  20. Ecological Impact and Carrying Capacity of Ponies

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The primary objectives of the study were to determine (1) the grazing patterns of the ponies living within the Chincoteague National Wildlife Refuge, (2) the effects...

  1. Influence of Low Molecular Weight Fractions of Humic Substances on Their Reducing Capacities and Distribution of Redox Functional Groups.

    Science.gov (United States)

    Yang, Z.; Jiang, J.

    2015-12-01

    Humic substances (HS) are redox-active organic compounds and their reducing capacities depend on molecule structure and distribution of redox functional groups (RFG). During dialysis experiments, initial HS were separated into low molecular weight fractions (LMWF, molecular weight dialysis device were calculated for initial HA, retentate and LMWF in native and reduced state, and result suggests that releasing of LMWF leads to production and explosion of RFG. LWMF have great fluorescence intensities for protein-like fluorophores and humic acids-like fluorophores (quinone-like functional groups), where quinonoid π-π* transition is responsible for the great reducing capacities of LMWF. The 3,500 Da molecules (0.25 nm diameter) of HS are capable of stimulating transformation of redox-active metals or potential pollutants trapped in soil micropores (< 2 nm diameter). A development of relationship between reducing capacity and Ex / Em position provides a possibility to predicate relative reducing capacities of HS in treated raw water sample.

  2. About rats and jackfruit trees: modeling the carrying capacity of a Brazilian Atlantic Forest spiny-rat Trinomys dimidiatus (Günther, 1877) - Rodentia, Echimyidae - population with varying jackfruit tree (Artocarpus heterophyllus L.) abundances.

    Science.gov (United States)

    Mello, J H F; Moulton, T P; Raíces, D S L; Bergallo, H G

    2015-01-01

    We carried out a six-year study aimed at evaluating if and how a Brazilian Atlantic Forest small mammal community responded to the presence of the invasive exotic species Artocarpus heterophyllus, the jackfruit tree. In the surroundings of Vila Dois Rios, Ilha Grande, RJ, 18 grids were established, 10 where the jackfruit tree was present and eight were it was absent. Previous results indicated that the composition and abundance of this small mammal community were altered by the presence and density of A. heterophyllus. One observed effect was the increased population size of the spiny-rat Trinomys dimidiatus within the grids where the jackfruit trees were present. Therefore we decided to create a mathematical model for this species, based on the Verhulst-Pearl logistic equation. Our objectives were i) to calculate the carrying capacity K based on real data of the involved species and the environment; ii) propose and evaluate a mathematical model to estimate the population size of T. dimidiatus based on the monthly seed production of jackfruit tree, Artocarpus heterophyllus and iii) determinate the minimum jackfruit tree seed production to maintain at least two T. dimidiatus individuals in one study grid. Our results indicated that the predicted values by the model for the carrying capacity K were significantly correlated with real data. The best fit was found considering 20~35% energy transfer efficiency between trophic levels. Within the scope of assumed premises, our model showed itself to be an adequate simulator for Trinomys dimidiatus populations where the invasive jackfruit tree is present.

  3. About rats and jackfruit trees: modeling the carrying capacity of a Brazilian Atlantic Forest spiny-rat Trinomys dimidiatus (Günther, 1877 – Rodentia, Echimyidae – population with varying jackfruit tree (Artocarpus heterophyllus L. abundances

    Directory of Open Access Journals (Sweden)

    JHF Mello

    Full Text Available We carried out a six-year study aimed at evaluating if and how a Brazilian Atlantic Forest small mammal community responded to the presence of the invasive exotic species Artocarpus heterophyllus, the jackfruit tree. In the surroundings of Vila Dois Rios, Ilha Grande, RJ, 18 grids were established, 10 where the jackfruit tree was present and eight were it was absent. Previous results indicated that the composition and abundance of this small mammal community were altered by the presence and density of A. heterophyllus. One observed effect was the increased population size of the spiny-rat Trinomys dimidiatus within the grids where the jackfruit trees were present. Therefore we decided to create a mathematical model for this species, based on the Verhulst-Pearl logistic equation. Our objectives were i to calculate the carrying capacity K based on real data of the involved species and the environment; ii propose and evaluate a mathematical model to estimate the population size of T. dimidiatus based on the monthly seed production of jackfruit tree, Artocarpus heterophyllus and iii determinate the minimum jackfruit tree seed production to maintain at least two T. dimidiatus individuals in one study grid. Our results indicated that the predicted values by the model for the carrying capacity K were significantly correlated with real data. The best fit was found considering 20~35% energy transfer efficiency between trophic levels. Within the scope of assumed premises, our model showed itself to be an adequate simulator for Trinomys dimidiatus populations where the invasive jackfruit tree is present.

  4. The maximum Sustainable Population Carrying Capacity of Water Resources Evaluation%基于最大可支撑人口水资源承载能力评价分析

    Institute of Scientific and Technical Information of China (English)

    罗铭; 刚傲

    2016-01-01

    In the modernization process of social transformation and development ,one of the important factors which influ-ence and restrict the Beijing -Tianjin - Hebei(BTH)wing area one of reality for the sustainable development is water short-age .This research is quantitative research by the method of carrying population in BTH region water can carry the size of population and economic development .Model validation results show that in the short term ,water quantity of the BTH re-gion population carrying capacity of rich ,can alleviate the contradiction between supply and demand of water resources ;But since the 2025 years ,because the population of the region water resources carrying capacity is insufficient ,the BTH region again go into a period of scarcity .After the implementation of south - to - north water diversion project ,BTH region ob-tained a certain degree of increase ,the water resources carrying capacity in population growth ,however ,under the situation of water resources carrying population are almost limited .Based on this ,the problem of water shortages in exploring the BTH resolution strategy ,not just focus on water saving and water diversion engineering problems ,also need to include for the population growth factors ,avoid excessive increase in population .Otherwise ,the results obtained with water ,is likely to be excessive increase of the population consume ,not really solve the problem of water shortage .%应用“承载人口数”方法定量研究了京、津、冀地区总的水资源所能承载的人口数量与经济发展规模。模型验证结果表明:在短期内,京、津、冀地区的水资源量人口承载能力富足,能缓解水资源供需矛盾;但从2025年后,由于该地区水资源量人口承载能力不足,则京、津、冀地区又重新陷入水资源匮乏时期。南水北调实施以后,京、津、冀地区水资源承载力获得了一定程度的增加,然而在人口增长的态势下,水资

  5. Estimation of Carrying Capacity of Manila Clam (Ruditapesphilippinarum) Culture Pond in Houhai Reclamation Area of Putian city,China%莆田后海垦区菲律宾蛤仔养殖池养殖容量的估算

    Institute of Scientific and Technical Information of China (English)

    杨淑芳; 张磊; 阎希柱

    2016-01-01

    From August 2013 to January 2014,the chlorophyll -a,primary productivity of phytoplankton,clams mortality rate in Houhai reclamation area of Putian were determined.The carrying capacity of the two Manila clam ponds wereestimated by Parsons TR-Takahashi M Ecological Trophodynamicsmodel [P=(BEn )×k]and Tait coastal energy flowing analysis model {B=[(0.1×C)/Q]×k}.Taking into consideration of the unused prima-ry productivity due to the pond effluent,the corrected results of two models were 5.52t and 7.10t for pond 1,with an average of 6.31t;3.60t and 4.62t for pond 2,with an average of 4.11t for two ponds.The actual yields of the two ponds accounted for 59.43%and 97.32%of the estimated capacities respectively.Two ponds of clam mortality rates were 23.43%and 22.5%,respectively.The capacity of pond 1 was significantly larger than that of pond 2.The pos-sible reasons are as follows:chl-a,the shapes of the pond,location and management.The carrying capacity of pond 2 was close to its actual yield.The estimated suitable breeding densities of Manila clam for pond 1 and for pond 2 were 0.61kg/m2 and 0.40kg/m2 respectively.As the actual breeding densities of two ponds are 0.19kg/m2 for each pond. The estimated suitable breeding density of Manila clam calculated from the carrying capacity was larger than the actu-al breeding density.A certain potential to increase the number of breeding clam exists.%2013年8月—2014年2月,对莆田后海垦区菲律宾蛤仔反季节高效生态养殖池叶绿素a、浮游植物初级生产量、蛤仔死亡率等进行了测定,采用ParsonsTR和TakahashiM营养动态模型和Tait沿岸海域能流分析模型对2个菲律宾蛤仔养殖池的养殖容量进行估算,扣除20%的日排水量导致的初级生产量损失,2种估算模型得到的养殖容量经校正后,池1为5.52t、7.1t,平均为6.31t;池2为3.60t、4.62t,平均为4.11t。两个花蛤养殖池的实际产量

  6. Examining the Resilience of Crop Production, Livestock Carrying Capacity, and Woodland Density in a Rural Zimbabwean Socio-Ecological System Using Agent-Based Models Representing Human Management Decisions

    Science.gov (United States)

    Eitzel Solera, M. V.; Neves, K.; Veski, A.; Solera, J.; Omoju, O. E.; Mawere Ndlovu, A.; Wilson, K.

    2016-12-01

    As climate change increases the pressures on arid ecosystems by changing timing and amount of rainfall, understanding the ways in which human management choices affect the resilience of these systems becomes key to their sustainability. On marginal farmland in Mazvihwa, Midlands Province, the historical carrying capacity of livestock has been consistently surprisingly high. We explore this phenomenon by building an agent-based model in NetLogo from a wealth of long-term data generated by the community-based participatory research team of The Muonde Trust, a Zimbabwean non-governmental organization. We combine the accumulated results of 35 years of indigenous and local knowledge with national datasets such as rainfall records. What factors keep the carrying capacity high? What management choices can maintain crops, livestock, and woodland at levels necessary for the community's survival? How do these choices affect long-term sustainability, and does increasing resilience at one scale reduce resilience at another scale? We use our agent-based model to explore the feedbacks between crops, livestock, and woodland and the impacts of various human choices as well as temporal and spatial ecological variation. By testing different scenarios, we disentangle the complex interactions between these components. We find that some factors out of the community's control can strongly affect the sustainability of the system through times of drought, and that supplementary feed may maintain livestock potentially at the expense of other resources. The challenges to resilience encountered by the farmers in Mazvihwa are not unique - many indigenous and rural people face drought and the legacies of colonialism, which contribute to lowered resilience to external challenges such as climate change, epidemics, and political instability. Using the agent-based model as a tool for synthesis and exploration initiates discussion about resilience-enhancing management choices for Mazvihwa's farmer-researchers.

  7. 基于RBF的指标规范值的水资源承载力评价模型%Evaluation Model of Carrying Capacity of Water Resources Represented with Normalized Indices Values Based on Radial Basis Function Neural Network

    Institute of Scientific and Technical Information of China (English)

    臧蕾; 刘伟; 李祚泳

    2012-01-01

    [Objective ] The aim was to study the assessment model of carrying capacity of water resources represented with normalized indices values based on radial basis function network ( RBF). [ Method] On the basis of the normalized transformation for indices, the basis function of model was universal for various indices and made representative calculation greatly simplified, as mean as normalized values of standards at all levels as the normalized values of each component of center vector for the basis functions in hidden nodes. [ Result] The RBF model optimized weight values by monkey king algorithm was applied to assess the carrying capacities of water resources in three districts of Changwu County of Shaanxi Province, the evaluation results were basically consistent with that of fuzzy assessment method. [ Conclusion] RBF model is simple and practical, and has universality and generality.%[目的]研究基于指标规范值的区域水资源承载力评价的径向基函数网络模型(RBF).[方法]在对指标进行规范变换的基础上,将指标各级标准规范值的平均值作为RBF的隐层节点基函数中心矢量各分量的规范值,因而基函数对各指标具有普适性,使基函数的表示和计算大为简化.[结果]将猴王算法优化网络权值得到的RBF模型应用于陕西省长武县3个区域水资源承载力的评价,其评价结果与模糊综合评价结果基本一致.[结论]RBF模型具有简单、实用的特点,具有普适性和通用性.

  8. 基于RBF的指标规范值的水资源承载力评价模型(英文)%Evaluation Model of Carrying Capacity of Water Resources Based on Standardized Indices of Radial Basis Function

    Institute of Scientific and Technical Information of China (English)

    臧蕾; 李祚泳; 刘伟

    2012-01-01

    [目的]研究基于指标规范值的区域水资源承载力评价的径向基函数网络模型(RBF)。[方法]在对指标进行规范变换的基础上,将指标各级标准规范值的平均值作为RBF的隐层节点基函数中心矢量各分量的规范值,因而基函数对各指标具有普适性,使基函数的表示和计算大为简化。[结果]将猴王算法优化网络权值得到的RBF模型应用于陕西省长武县3个区域水资源承载力的评价,其评价结果与模糊综合评价结果基本一致。[结论]RBF模型具有简单、实用的特点,具有普适性和通用性。%[Objective] The aim was to study on RBF model about evaluation on carrying capacity of water resources based on standardized indices. [Method] The indices were transformed and the averages of standard values in different levels were taken as the standardized values of components of central vectors for basic functions of RBF hidden nodes. Hence, the basic functions are suitable for most indices, simplifying expression and calculation of basic functions. [Result] RBF models concluded through Monkey-king Genetic Algorithm with weights optimization are used in evaluation on water carrying capacity in three districts in Changwu County in Shaanxi Province, which were in consistent with that through fuzzy evaluation. [Conclusion] RBF, simple and practical, is universal and popular.

  9. 西安市生态足迹与生态承载力动态变化与预测%Research on Dynamic Change Analysis and Prediction of Ecological Footprint and Ecological Carrying Capacity in Xi’an City

    Institute of Scientific and Technical Information of China (English)

    袁钟; 赵牡丹; 刘蕊娟; 王静

    2016-01-01

    Ecological footprint method by converting the regional resources and energy consumption to the area of various kinds of land of the production providing this kind of material flow , and compare with the same land area that can provide the ecological productive (ecological carrying capacity),it can quantitatively determine whether the development of a region in the scope of the ecological carrying capacity. In this paper, using the method of ecological footprint and ARIMA model to calculate account of biological and energy resources of ecological footprint of Xi' an from 1994 to 2013,and research on dynamic change,predict ecological footprint and ecological capacity in Xi ’an city.The results showed that ecological footprint is greater than the ecological capacity in Xi’an in 2013.ecological footprint is eight times of ecological carrying capacity from 1994 to 2013 in Xi 'an, and sustained severe ecological deficit. The intensity of production and life is more than the carrying capacity of the ecosystem, it ’s under the excessive exploitation and utilization of the human.ARIMA model prediction shows that the ecological footprint has a tendency in the next five years, but the gap between ecological footprint and ecological carrying capacity is very large. Through the analysis of influence degree of pressure of human activities on the natural ecological system.it can provide new train of thought and direction for urban ecological research, ecological construction and sustainable development . With strengthening the construction of urban ecological , optimizing the urban management mode and the industrial structure,it is an effective way to sustainable development and ecological security in Xi’an.%生态足迹法通过将区域的资源和能源消费转化为提供这种物质流所必须的各种生物生产土地的面积,并同区域能提供的生态生产型土地面积(生态承载力)进行比较,能定量判断一个区域的发展是否处于生

  10. Evaluation of Land Resources Carrying Capacity in Panjin City Based on Remote Sensing%基于遥感影像的盘锦市土地资源承载力评价研究

    Institute of Scientific and Technical Information of China (English)

    任家强; 席秋红; 王婷

    2014-01-01

    本文以盘锦市作为研究区,通过对盘锦市2000年、2004年和2010年三个时间段的Landsat TM遥感影像处理,获取盘锦市2000年、2004年和2010年的土地利用数据,并综合考虑人口-资源-环境之间的协调发展,构建了盘锦市土地承载力评价体系,运用层次分析法及多因素加权求和法,对盘锦市土地资源承载力进行评价研究。%Taking Panjin City as study area, through the 2000, 2004 and 2010 Landsat TM remote sensing image, the land use data of 2000, 2004 and 2010 were obtain .Considering the coor-dinated development between the population-resources-environ-ment, build the PanJin City land Resources Carrying Capacity evaluation system, using the analytic hierarchy process (AHP) and multifactor weighted summation method, to evaluate PanJinShi bearing capacity of land resources research.

  11. Robo-line storage: Low latency, high capacity storage systems over geographically distributed networks

    Science.gov (United States)

    Katz, Randy H.; Anderson, Thomas E.; Ousterhout, John K.; Patterson, David A.

    1991-01-01

    Rapid advances in high performance computing are making possible more complete and accurate computer-based modeling of complex physical phenomena, such as weather front interactions, dynamics of chemical reactions, numerical aerodynamic analysis of airframes, and ocean-land-atmosphere interactions. Many of these 'grand challenge' applications are as demanding of the underlying storage system, in terms of their capacity and bandwidth requirements, as they are on the computational power of the processor. A global view of the Earth's ocean chlorophyll and land vegetation requires over 2 terabytes of raw satellite image data. In this paper, we describe our planned research program in high capacity, high bandwidth storage systems. The project has four overall goals. First, we will examine new methods for high capacity storage systems, made possible by low cost, small form factor magnetic and optical tape systems. Second, access to the storage system will be low latency and high bandwidth. To achieve this, we must interleave data transfer at all levels of the storage system, including devices, controllers, servers, and communications links. Latency will be reduced by extensive caching throughout the storage hierarchy. Third, we will provide effective management of a storage hierarchy, extending the techniques already developed for the Log Structured File System. Finally, we will construct a protototype high capacity file server, suitable for use on the National Research and Education Network (NREN). Such research must be a Cornerstone of any coherent program in high performance computing and communications.

  12. Development of Grain Production and Spatial Pattern of Land Carrying Capacity in Chongqing City%重庆市粮食生产发展特征及土地资源承载力空间格局研究

    Institute of Scientific and Technical Information of China (English)

    施开放; 刁承泰

    2012-01-01

    首先分析了1985—2010年重庆市粮食生产发展过程的特点,随后以人粮关系为基础,构建了土地资源承载力(LCC)模型和土地资源承载指数(LCCI)模型,从区县尺度对重庆市土地资源承载力空间格局现状进行了分析。结果表明:1985—2010年重庆市粮食生产呈周期性波动特征,具有明显的不稳定性;人均粮食占有量起伏较小,基本维持在356.5kg/人左右,人口增幅略小于粮食产量增幅。2009年重庆市区县土地资源承载力主要以人口超载、粮食短缺为主要特征。都市发达经济圈的8个区县以及渝东北翼的大部分区县表现为粮食亏缺、人口超载,渝东南翼的大部分区县以及渝西的大部分区县表现为人粮均衡,只有合川区、南川区、黔江区、石柱县和秀山县5个区县处于粮食盈余状态。因此必须加强重庆各区县以及重庆市与其他省市之间的粮食贸易和调配来满足人口超载区的粮食需求。%With the growth of population,land carrying capacity and food safety have attracted great attention worldwide.In this study,the characteristics of development of grain production in Chongqing City were analyzed and summarized firstly,and then,land carrying capacity(LCC) and land carrying capacity index(LCCI) models were developed from the point of man-grain relationship.Finally,the LCCI was calculated for each county of Chongqing in 2009,and the current situation of land carrying capacity and its spatial pattern were systematically evaluated.The results showed that: from 1985 to 2010,the grain production of Chongqing City presented an upward tendency and the population growth rate was less than that of grain yield,and the grain yield per capita kept stable;food deficits and population overloading remained the primary characteristics of LCC of Chongqing City at a county scale in 2009.The 8 counties of Metropolitan Developed Circle and the counties of Northeast of

  13. Water resources carrying capacity of Xianyang City based on system dynamics%基于系统动力学的咸阳市水资源承载力

    Institute of Scientific and Technical Information of China (English)

    黄蕊; 刘俊民; 李燐楷

    2012-01-01

    Based on the principles and methods of system dynamics, carrying capacity of water resources system of Xianyang City is divided into industrial, agricultural, life and ecology, water and wastewater treatment and reuse subsystem. Regarding water shortage level as the main feedback factor, considering people "s decision-making preferences of using water when water is in shortage, a system dynamics model of water resources carrying capacity of Xianyang City was established by means of the feedback relationships between the various subsystems. The simulation results showed that if the city is being developed according to the trend-based development plan, it will be subject to severe water shortage (in a level of 9% to 35% ) in planning year since the agricultural and ecological water was diverted to the rapidly developing industry. If the city is developed in the track of resource-based and environmental protection, the ecological environment will be protected very well; however, industrial and agricultural development will be severely constrained. If the city is adopted an economic development plane, even though industry development will be rapid, the city will be subject to agricultural irrigation decreased, environment degraded, serious over-exploitation of ground water, causing 3% -5% water shortage, eventually leading to poor sustainable development. If the city is indicated to choose a coordinated development mode,a 13. 8% growth rate of industry and agriculture will be maintained,more wastewater treated will be reused, agricultural irrigation area will be expanded steadily, and ecological environment will be improved in a great deal, water shortage will be as low as 0. 4%. It suggests this plan is the optimal solution to make sure water resources carrying capacity of Xianyang City will be kept in sustainable manner.%基于系统动力学的原理和方法,将水资源承载力系统划分为工业、农业、生活、生态、水资源和污水处理回用子

  14. The capacity to cope with climate warming declines from temperate to tropical latitudes in two widely distributed Eucalyptus species.

    Science.gov (United States)

    Drake, John E; Aspinwall, Michael J; Pfautsch, Sebastian; Rymer, Paul D; Reich, Peter B; Smith, Renee A; Crous, Kristine Y; Tissue, David T; Ghannoum, Oula; Tjoelker, Mark G

    2015-01-01

    As rapid climate warming creates a mismatch between forest trees and their home environment, the ability of trees to cope with warming depends on their capacity to physiologically adjust to higher temperatures. In widespread species, individual trees in cooler home climates are hypothesized to more successfully acclimate to warming than their counterparts in warmer climates that may approach thermal limits. We tested this prediction with a climate-shift experiment in widely distributed Eucalyptus tereticornis and E. grandis using provenances originating along a ~2500 km latitudinal transect (15.5-38.0°S) in eastern Australia. We grew 21 provenances in conditions approximating summer temperatures at seed origin and warmed temperatures (+3.5 °C) using a series of climate-controlled glasshouse bays. The effects of +3.5 °C warming strongly depended on home climate. Cool-origin provenances responded to warming through an increase in photosynthetic capacity and total leaf area, leading to enhanced growth of 20-60%. Warm-origin provenances, however, responded to warming through a reduction in photosynthetic capacity and total leaf area, leading to reduced growth of approximately 10%. These results suggest that there is predictable intraspecific variation in the capacity of trees to respond to warming; cool-origin taxa are likely to benefit from warming, while warm-origin taxa may be negatively affected.

  15. Séverisation de l'essai de capacité de charge des lubrifiants sur machine a engrenages FZG Obtaining Greater Severity for the Load-Carrying Capacity Test for Lubricants with the Fzg Gear Machine

    Directory of Open Access Journals (Sweden)

    Ayel J.

    2006-11-01

    Full Text Available La machine à engrenages FZG reste l'appareil de laboratoire le plus utilisé pour l'évaluation de la capacité de charge des lubrifiants pour engrenages et transmissions. Mais, les différentes méthodes normalisées actuellement utilisées ne sont pas assez sévères pour bien discriminer les huiles extrême-pression actuelles en ce qui concerne leur capacité de charge. L'institut Français du Pétrole a développé une méthode beaucoup plus sévère, tout en restant aussi répétable que les méthodes classiques, sans modification de la machine ou des engrenages et, par conséquent, aisément utilisable dans tous les laboratoires. Cette nouvelle procédure est applicable à vitesse double de la vitesse normale sans accroissement de l'état des contraintes des dentures. L'utilisation de cette méthode devrait rendre de grands services aux formulateurs d'huiles et aux fabricants d'additifs pour la mise au point de leurs produits. The FZG gear machine is still the most widely used laboratory device for assessing the load-carrying capacity of lubricants for gears and transmissions. But various standardized methods currently used are not severe enough to effectively discriminate present extreme- pressure oils with regard to their load-carrying capacity. The Institut Français du Pétrole has developed a much more severe method that remains just as repeatable as conventional methods, without modifying the machine or the gears, and hence that can easily be used in all laboratories. This new procedure can be implemented at twice normal speed without any increase in the state of stresses on teeth. The use of this method should be of great service to oil formulators and additive manufacturers in the development of their products.

  16. DYNAMIC ANALYSIS OF WATER RESOURCES ECOLOGICAL FOOTPRINT AND ECOLOGICAL CARRYING CAPACITY IN YUNNAN PROVINCE%云南省水资源生态足迹与生态承载力动态分析

    Institute of Scientific and Technical Information of China (English)

    常龙芳

    2012-01-01

    利用水资源生态足迹计算模型对云南省近十年水资源生态足迹和生态承载力进行了分析,结果表明:(1)云南省近十年水资源生态承载力差异较大,2001年最高,为285×10^6hm^2,2009年最低,为175×10^6hm^2,而水资源生态足迹变化不明显;(2)人均水资源生态足迹在0.5306hm^2/人~0.5669hm^2/人,万元GDP水资源生态足迹呈逐年下降的趋势;(3)各用水指标中生产用水水资源生态足迹所占份额最大,均大于21.0×10^6hm^2,生态环境用水所占份额最小,均小于1.0×10^6hm^2。%According to the calculation model of water resources ecological footprint, the water resources ecological footprint and ecological carrying capacity in the last ten years in Yunnan Province were analyzed. The results showed: ( 1 ) There are big differences in the ecological carrying capacity in the last ten years, the maximum of 285 × 10^6hm^2 in 2001, and the minimum of 175× 10^6hm^2 in 2009, but the water resources ecological footprint is nearly on the same level; (2) The ecological footprint of water resources per capita was at the range of 0. 5306 hm^2 -0. 5669hm^2, while the water resources ecological footprint per 104 yuan GDP continued to decrease; (3) Production water resources accounted for the largest ecological footprint among all the using water index, all over 21.0 × 10^6hm^2, and ecological environment water consumption was the least, all under 1.0 × 10^6hm^2.

  17. 考虑后屈曲的复合材料加筋壁板承载能力分析%Load Carrying Capacity Analysis of Stiffened Composite Panel Considering Post-buckling

    Institute of Scientific and Technical Information of China (English)

    张国凡; 孙侠生; 孙中雷

    2015-01-01

    The load carrying capacity prediction of stiffened composite structure is an important part of air-craft designing,and the key problem is post-buckling analysis taken material failure into account.A con-cise progressive damage analysis methodology considering intralaminar failure,delamination and stiffness degradation was established based on cohesive elements and Hashin damage criteria subjected to the post-buckling analysis beared compressive loading,and UMAT subroutines of ABAQUS were developed.The comparison indicates that the load carrying capacity,failure mode and strain analysis results of this paper agree well with test results,and the relative error is less than 10% which proves the effectiveness of the present methodology.%复合材料加筋结构的承载能力预估是飞机设计中的重要内容,其关键问题就是考虑材料失效的后屈曲分析。针对复合材料加筋壁板承受压缩载荷的后屈曲承载能力预估问题,考虑层内损伤、层间分层以及刚度退化,基于内聚力单元与Hashin损伤准则,建立了一种简洁的渐进损伤分析方法,编制了相应的ABAQUS UMAT子程序,并利用复合材料加筋结构破坏试验进行了验证。验证结果表明,预估的承载能力、破坏模式和结构应力状态与物理试验结果符合得很好,承载能力误差在10%以内,证明了方法的准确性和工程实用性。

  18. Capacity of high-resolution data and modelling techniques to predict drivers and distributions of vulnerable deep-sea ecosystems

    DEFF Research Database (Denmark)

    Mohn, Christian; Rengstorf, Anna; Brown, Colin;

    , facilitating species distribution modelling with high spatial detail. In this study, we used high resolution data (250 m grid size) from a newly developed hydrodynamic model to explore linkages between key physical drivers and occurrences of the cold-water coral Lophelia pertusa in selected areas of the NE...... Atlantic. Further, these model data were combined with high resolution terrain attributes and video transect derived species distribution data to test the capacity of multi-parameter high-resolution data for improving the predictive skill of species distribution models using Lophelia pertusa as a case...... study. The study shows that predictive models incorporating hydrodynamic variables perform significantly better than models based on terrain parameters only. They are a potentially powerful tool to improve our understanding of deep-sea ecosystem functioning and to provide decision support for marine...

  19. Evaluation on Population Carrying Capacity of Cultivated Land Based on Human - grain Relationship in Chengdu%基于人粮关系的成都市耕地资源人口承载力研究

    Institute of Scientific and Technical Information of China (English)

    吕秋俊; 李晓

    2016-01-01

    With the acceleration of urbanization process,the situation of cultivated land resources in Chengdu city has changed significantly,and the food security has become increasingly prominent. Combined with the characteristics of the dynamic changes of the actual cultivated land resources,grain and population in 2003 ~2012 in Chengdu,this paper analyzes the productive potential of cultivated land resources and population carrying capacity of land resources, aiming at 2016 ~ 2020,using GM(1,1)grey system forecasting model to predict the development tendency of culti-vated land area,per unit area yield of grain and population,etc. According to the three consumption levels of saturat-ed,comparatively well - off and surplus,the population supporting capacity of land resources in forecasted years have been discussed. Finally,some countermeasures are put forward to enhance the population supporting capacity of land resources and achieve the sustainable development of cultivated land resources.%随着城镇化进程加快,成都市耕地资源现状发生显著变化,粮食安全问题日益凸显。结合成都市2003-2012年耕地资源、粮食与人口动态变化特点,分析其现实耕地资源生产潜力和人口承载力;以2016-2020年为目标年,运用 GM(1,1)灰色系统预测模型对耕地面积、粮食单产、人口等的发展趋势进行预测;并结合温饱型、小康型与富裕型三种不同的粮食消费标准对预测年份内耕地资源的人口承载力状况进行分析。最后提出了提高人口承载力、实现耕地资源可持续发展的对策与措施。

  20. Peer-assisted content distribution networks: performance gains and server capacity savings

    NARCIS (Netherlands)

    I. Rimac; S.C. Borst (Sem); A. Walid

    2008-01-01

    htmlabstractContent distribution networks are experiencing tremendous growth, in terms of traffic volume, scope, and diversity, fueled by several technological advances and competing paradigms. Traditional client/server architectures as deployed in the majority of today's commercial networks provide

  1. Identification and Distribution of the Clinical Isolates of Imipenem-resistant Pseudomonas aeruginosa Carrying Metallo-β-lactamase and/or Class 1 Integron Genes

    Institute of Scientific and Technical Information of China (English)

    Xi CHENG; Pinjia WANG; Yue WANG; Hong ZHANG; Chuanmin TAO; Weiqing YANG; Mei LIU; Wenxiang JIA

    2008-01-01

    To investigate the distribution of the genes of two major metallo-β-lactamases (MBL; i.e., IMP and VIM) and class 1 integrons (intI) in the clinical imipenem-resistant Pseudomonas aeruginosa, a total of 65 isolates, from a university hospital in Sichuan between December 2004 and April 2005 were screened for MBL genes by PCR using primers specific for blaIMP-1, blaVIM and blaVIM-2 genes. The MBL-positive isolates were further assessed for class 1 integrons by PCR using specific primers. The nucleotide sequences of several PCR products were also determined. The results revealed that the blaVIM gene was found in 81.5% (53/65) of all isolates, bla gene was found in only 1 isolate and the intI gene was observed in 45.3% (24/53) of blaVIM-positive isolates. One isolate carried simultaneously both blaIMP-1 and intI genes, and to the best of our knowledge this is the first report of such isolate in southwest China. These observations highlight that the genes for VIM β-lactamase and class 1 integrons were predominantly present among the imipenem-resistant P. aeruginosa tested, confirming the current widespread threat of imipenem-resistant, integron-borne P. aeruginosa.

  2. Correlations of the instantaneous carrying force and pressure distribution in the case of the narrow sliding radial bearing under hard shocks

    Science.gov (United States)

    Alexandrescu, I. M.; Coteţiu, R.; Darabă, D.

    2017-02-01

    We present the determining relationship of carriage in non-dimensional form for narrow radial bearings subjected to shocks and vibrations, as well as the determining relationships of the lubricant minimum thickness in relation to the dynamic loading. Due to the very short time of loading radial bearings subjected to shocks and vibrations, of about 0.5-1 ms, we consider only the approaching motion between spindle/axle and bushing on the direction of the centre line, without the rotation of the spindle/axle (the case of the non-rotating bearing), so that the effect of the lubricant expulsion be prevalent in the achieving of the self-carrying film. The paper is focused on determining relationship of carriage in dimensional form for narrow radial bearings exposed to shocks and vibrations, as well as the determining relationships of the pressure distribution from the film to be lubricated in various places of the bearing’s body. It is showed the details during the measuring accomplishments and the experimental results are registered in a record of obtained results. This paper was accepted for publication in Proceedings after double peer reviewing process but was not presented at the Conference ROTRIB’16

  3. 北京密云水源地村级尺度生态安全承载力分析%Analysis of Eco-security Carrying Capacity on Village Scale in Miyun Reservoir, Beijing

    Institute of Scientific and Technical Information of China (English)

    胡艳霞; 周连第; 李红; 王亚芝; 解海静

    2011-01-01

    It' s important to study on the eco-security capacity of a social-economic-natural compounding system in certain areas, especially for sustainable development in urban watershed. The author took a village of Miyun watershed for an example to study the eco-security carrying capacity by using the method of system dynamics (SD) model simulation, aimed to solve the problems between industry development and environment. It explained that small agro-bio-cycle system could increase eco-security carrying capacity remarkably, but must be combined with village tour which developed rapidly. During the research, the eco-security had been divided into 4 subsystem, such as population, bio-cycle agriculture, village tourism and waste resources, then 9 schemes had been searched and system dynamics model had been built. The simulation results showed that: (1) mushroom industry was the ligament for the small eco-cycle system, and if all the greenhouse in the village had been used to produce mushroom, the eco-security would be better in the coming 10 years; (2) if the stalks, cattle manure, tree branches, mushroom sticks and waste water had been treated to 60%, the balance point for ecology and economy was coming, that is, the ecology and economy of the village would be in order and sustainable in the coming 10 years.%区域生态安全承载力的研究对于一定区域的社会-经济-自然复合生态经济系统的持续发展,尤其是大都市水源地的持续发展具有重要意义.笔者以北京密云水源地的1个村庄为案例,针对产业发展与环境矛盾突出问题,采用系统动力学的方法,从村级尺度上阐述了产业发展的农业生物小循环方式是显著提高生态安全承栽力的有效方法,但同时还需紧密结合该区域内发展迅速的民俗旅游产业,才能有效解决北京水源地的持续发展问题.研究中将生态安全承载力系统划分为人口、生物循环农业、旅游、废污资源4个子系统,构建

  4. Constant Power Generation of Photovoltaic Systems Considering the Distributed Grid Capacity

    DEFF Research Database (Denmark)

    Yang, Yongheng; Blaabjerg, Frede; Wang, Huai

    2014-01-01

    With an imperative demand of clean and reliable electricity generation in some countries, the increasing adoption of new photovoltaic (PV) systems pushes the Distribution System Operators (DSOs) to expand the transmission/distributed lines. However, the potential cost brought by such extensions...... systems in CPG operation mode are also discussed in this paper. Additionally, the loss of energy is calculated to reveal the viability of the proposed CPG control method. Operation examples of a PV system are presented to show the effectiveness of the CPG control method to unload the distributed grid....... and increased maintenances introduce new obstacles. In view of this concern, the DSOs starts to reduce PV installations in order to avoid an extension of the power infrastructure. Besides, another alternative solution is to limit the maximum feed-in power of the existing PV systems to a certain level. It can...

  5. Utilizing Electric Vehicles to Assist Integration of Large Penetrations of Distributed Photovoltaic Generation Capacity

    Energy Technology Data Exchange (ETDEWEB)

    Tuffner, Francis K.; Chassin, Forrest S.; Kintner-Meyer, Michael CW; Gowri, Krishnan

    2012-11-30

    Executive Summary Introduction and Motivation This analysis provides the first insights into the leveraging potential of distributed photovoltaic (PV) technologies on rooftop and electric vehicle (EV) charging. Either of the two technologies by themselves - at some high penetrations – may cause some voltage control challenges or overloading problems, respectively. But when combined, there – at least intuitively – could be synergistic effects, whereby one technology mitigates the negative impacts of the other. High penetration of EV charging may overload existing distribution system components, most prominently the secondary transformer. If PV technology is installed at residential premises or anywhere downstream of the secondary transformer, it will provide another electricity source thus, relieving the loading on the transformers. Another synergetic or mitigating effect could be envisioned when high PV penetration reverts the power flow upward in the distribution system (from the homes upstream into the distribution system). Protection schemes may then no longer work and voltage violation (exceeding the voltage upper limited of the ANSI voltage range) may occur. In this particular situation, EV charging could absorb the electricity from the PV, such that the reversal of power flow can be reduced or alleviated. Given these potential mutual synergistic behaviors of PV and EV technologies, this project attempted to quantify the benefits of combining the two technologies. Furthermore, of interest was how advanced EV control strategies may influence the outcome of the synergy between EV charging and distributed PV installations. Particularly, Californian utility companies with high penetration of the distributed PV technology, who have experienced voltage control problems, are interested how intelligent EV charging could support or affect the voltage control

  6. Integration of Electric Vehicles into the Power Distribution Network with a Modified Capacity Allocation Mechanism

    DEFF Research Database (Denmark)

    Hu, Junjie; Morais, Hugo; Sousa, Tiago

    2017-01-01

    The growing penetration of electric vehicles (EVs) represents an operational challenge to system operators, mainly at the distribution level by introducing congestion and voltage drop problems. To solve these potential problems, a two-level coordination approach is proposed in this study......-VPPs, considering the case of EVs charging and discharging. The three mechanisms include: (1) a market-based approach; (2) a pro-rata approach; and (3) a newly-proposed constrained market-based approach. A case study considering a 37-bus distribution network and high penetration of electric vehicles is presented...

  7. 基于土地消纳粪便能力的畜禽养殖承载力%Carrying capacity of livestock and poultry breeding based on feces disposal volume of land

    Institute of Scientific and Technical Information of China (English)

    潘瑜春; 孙超; 刘玉; 唐秀美; 任艳敏

    2015-01-01

    The livestock and poultry breeding industry in Pinggu district of Beijing developed rapidly. Compared with 1992, the slaughter of pigs and chickens increased by 18.95% and 22.29%, and the breeding stock of cattle, sheep, laying hens increased by 35.51%, 40.28% and 10.29%, especially the pig slaughter and egg production, which occupied by 11.81% and 20.21% of Beijing respectively. Gradually, the environmental pressure appears caused by the rapid growth of livestock and poultry manure quantity. And Pinggu district, the ecological conservation district, ecological barrier and water source protection of Beijing, is of a great importance to keep the environment of Beijing sustainable and healthy. As a result, it is important to connect farming and aquaculture, construct the circulation of agriculture economy chain, and determine the scale of farming according to local conditions. Based on the characteristic that orchard land took a large part of agricultural land, this paper set the cultivated land and orchard nitrogen limited standard, through calculation of the environmental capacity of farmland nitrogen, the poultry and animal feces pollution risk index and potential of livestock and poultry, then assessed the livestock carrying potential and potential contamination and analyzed the farmland and orchards’ livestock carrying potential of Pinggu and its town. The results indicated that: 1) During 2012, the total manure of Pinggu was 591 100 tons, containing nitrogen and phosphorus respectively 4 721, 998 t, which meant a huge organic resource, made it available to reduce the fertilizer use, and can effectively improve soil quality and the quality of the crops; 2) For ecological conservation development area, as the orchards occupied a large proportion of agricultural land, the agricultural land of livestock and poultry manure loading status achieved by taking the cultivated land and orchard as disposal site, may be more practical. The average manure load of

  8. 基于人粮关系的咸宁市土地承载力研究%Study on Carrying Capacity of Land Resources in Xianning City Based on Population-Grain Relationship

    Institute of Scientific and Technical Information of China (English)

    郝汉舟; 汪华

    2014-01-01

    In this study, the grey model GM(1,1) and the Logistic model were used to predict the changes in the future popu-lation, farmland and grain yield per unit area of Xianning city , Hubei province .The piecewise-revised model by using environ-mental factors was adopted to calculate the production potential of arable land in Xianning city .The results showed that:(1) the av-erage grain yield per unit area of arable land in Xianning city in 2011 was 6575.4 kg/hm2 , the theoretical production potential of ar-able land was 23760.2 kg/hm2, and the former accounted for 27.7% of the latter; (2) in 2011, the carrying capacity of arable land for food in Xianning city was great , and the population carrying index LCCI of every county ( except for Jiayu county ) was grea-ter than 1;(3) it was predicted that the grain yield per unit area of Xianning city in 2015 and 2025 was 8473.1 kg/hm2 and 9441. 7 kg/hm2 respectively;the predicted population of this city in 2015 and 2025 was 3.019 million and 3.243 million respectively;(4) as for the well-off-type population carrying capacity , LCCI in Xianning city was 0.79 in 2015 and 0.59 in 2025, and the population saturability revealed a downward trend .%以湖北省咸宁市为例,采用灰色模型GM(1,1)及逻辑斯蒂模型分别预测咸宁市未来人口、耕地及粮食单产的变化。采用环境因子逐段订正模型计算咸宁市土地耕地生产潜力,研究结果表明:咸宁市2011年耕地单产平均水平为6575.4 kg/hm2,理论计算的耕地生产潜力为23760.2 kg/hm2,实际单产为潜在耕地生产潜力的27.7%。2011年咸宁市耕地粮食承载力压力很大,除嘉鱼县外,人口承载指数LCCI均大于1。2015年和2025年咸宁市粮食单产预测为8473.1 kg/hm2和9441.7 kg/hm2。2015年和2025年人口预测为301.9万和324.3万。对于小康型人口承载力来讲,人口承载指数LCCI,在2015年为0.79,在2025年为0.59,人口饱和度呈现下降的趋势。

  9. 基于人粮关系的重庆市土地资源承载力水平时空差异研究%Spatial-Temporal Difference Analysis of Land Carrying Capacity Based on Man-Grain Relationship in Chongqing Municipality

    Institute of Scientific and Technical Information of China (English)

    孙秀锋; 秦建; 刁承泰; 左太安

    2014-01-01

    With the increase of population ,land carrying capacity and regional food security have attracted great attention worldwide .Evaluating regional land carrying capacity and analyzing its spatial‐temporal difference are important for regional grain security and land resource sustainable utilization .Based on the relationship between population and grain ,land carrying capacity (LCC) and land carrying capacity index (LCCI) models are built in this study to analyze the temporal and spatial disparities of land carrying capaci‐ty of each county/district in Chongqing so as to provide a scientific basis for decision‐making and overall planning of land use and sustainable development .In the period from 2004 to 2010 ,the gap in land carry‐ing capacity level between various counties/districts of Chongqing city became increasingly larger and the overloading of land resources was serious .In the 7 years ,the quantitative distribution of various levels of land carrying capacity of the 40 counties/districts exhibited an M‐shaped model .The counties showing the critical overload and over‐balanced situations stood on the peaks of “M” ,seriously overloaded counties/dis‐tricts lay in the middle of “M”and overload and surplus counties/districts were at the bottom ends of “M”. In the same period ,the number of the counties/districts of Chongqing with coordinated levels of land car‐rying capacity and social and economic development remained unchanged ,the number of the counties/dis‐tricts w hose social and economic development lagged behind their land carrying capacity diminished ,and the number of the counties/districts whose social and economic development surpassed their land carrying capacity increased from 13 in 2004 to 15 in 2010 .%定量评价区域土地资源承载力水平以及时空差异对于区域粮食安全和土地资源可持续利用起着至关重要的意义.论文以人口和粮食关系,建立土地资源承载力模型和土

  10. Quantum-Locked Key Distribution at Nearly the Classical Capacity Rate

    Science.gov (United States)

    Lupo, Cosmo; Lloyd, Seth

    2014-10-01

    Quantum data locking is a protocol that allows for a small secret key to (un)lock an exponentially larger amount of information, hence yielding the strongest violation of the classical one-time pad encryption in the quantum setting. This violation mirrors a large gap existing between two security criteria for quantum cryptography quantified by two entropic quantities: the Holevo information and the accessible information. We show that the latter becomes a sensible security criterion if an upper bound on the coherence time of the eavesdropper's quantum memory is known. Under this condition, we introduce a protocol for secret key generation through a memoryless qudit channel. For channels with enough symmetry, such as the d-dimensional erasure and depolarizing channels, this protocol allows secret key generation at an asymptotic rate as high as the classical capacity minus one bit.

  11. A LOCATION-INVENTORY MODEL INCLUDING DELIVERY DELAY COST AND CAPACITY CONSTRAINTS IN A STOCHASTIC DISTRIBUTION NETWORK

    Directory of Open Access Journals (Sweden)

    A. Ahmadi Javid

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: In this paper, we present a distribution network design problem in a supply chain system that minimises the total cost of location, inventory, and delivery delay. Customers’ demands are random, and multiple capacity levels are available for the distribution centers. The problem is first formulated as a mixed integer convex programming model to optimally solve medium-sized instances, and then a heuristic is developed for solving large-sized instances.

    AFRIKAANSE OPSOMMING: In hierdie artikel word ‘n distribusienetwerkprobleem in ‘n voorsieningsketting voorgehou waar die totale koste van die ligging, voorraad en afleweringsvertragings geminimiseer word. Die vraag is lukraak en verskeie kapasiteitsvlakke is beskikbaar in die verspreidingsentra. Die problem word eers geformuleer as ‘n gemengde-heeltal-konvekse model sodat mediumgrootte gevalle geoptimiseer kan word, waarna ‘n heuristieke benadering ontwikkel word vir die oplos van grootskaalse aktiwiteite.

  12. POPULATION DENSITIES AND THE RANGE-CARRYING ...

    African Journals Online (AJOL)

    CAPACITY FOR LARGE MAMMALS IN QUEEN ELIZABETH ... The highest known densities oflarge terrestrial mammals occur on the grasslands in ...... It is estimated that the proper average biomass carrying capacity for the several herbivore.

  13. Exploitation Potential and Carrying Capacity of Water Resources of the Yinghe River Basin%颍河流域水资源开发潜力与承载力分析

    Institute of Scientific and Technical Information of China (English)

    陈杰; 欧阳志云

    2011-01-01

    Water pollution and water shortage is a key factor to affect the eco - socio - economic sustainable development in the Ying River Basin By using water load index and building water supple and demand equilibrium model, this paper analyzed the exploitation potential and population carrying capacity of the basin' s water resources. The results showed that water load index of the overall basin was 19. 24, about half of counties and cities greater than 20, which suggested a high degree of water resources utilization and small potential of further development for the basin. According to statistical data, the average amount of water resources of Yinghe River Basin is 94. 51 × 108m3. In addition, there are about 23.69 × 1O8m3 of water that can be quoted from outside the basin in the future. Based on the total amount of available water, the water resources carrying capacity ( WRCC ) of Yinghe River Basin was 27. 33 million persons in 2008, overloading 10. 88%. The equilibrium model predicts that the basin' s WRCC is 35.91 million persons in 2020, 11.62% higher than the expected population. Because of serious surface water pollution, the actual WRCC may be smaller than the above values, if the effects of water quality, water supply guarantee rate and climate changing were considered. These results provide important references for Yinghe River Basin to use water resources rationally, promote saving water and pollution control and plan long - term socio - economic development.%水环境污染和水资源短缺是影响颍河流域生态社会经济可持续发展的重要因素.研究通过水资源负载指数、水资源供需平衡模型分析了颍河流域水资源的开发利用潜力和人口承载力.结果表明,颍河流域水资源利用程度较高,流域整体负载指数为19.24,约一半县市的负载指数大于20,今后进一步开发的潜力较小;流域多年平均水资源量为94.51亿m3,可引用流域外水资源潜力约23.69亿M3,以水资源

  14. 水电梯级开发对生态承载力影响的研究%Evaluation of the ecosystem carrying capacity impact caused by the cascade hydropower development

    Institute of Scientific and Technical Information of China (English)

    王丽萍; 郑江涛; 周晓蔚; 黄小锋; 张验科

    2011-01-01

    By the theory of ecological carrying capacity (ECC) based on ecosystem health, evaluation indices and assessing standards for the ECC impact caused by cascade hydropower development were proposed. A corresponding evaluation model based on the projection pursuit (PP) and immune evolutionary algorithm was established. A case study of the Nujiang River in Yunnan Province shows that all the ECC indices of this area keep increasing at different stages of watershed exploitation. On completion of the planned hydropower development,the synthesis ECC index of this watershed will increase by 8.6%.%基于生态系统健康的生态承载力理念,提出了水电梯级开发对区域生态承载力影响的评价指标体系,建立了基于投影寻踪的评价模型.以怒江州为研究区域,对水电梯级开发对生态承载力的影响进行了深入分析.研究结果表明:怒江中下游水电梯级开发规划实施的不同阶段对怒江州生态承载力均为正面影响.梯级开发规划全面实施后,通过生态承载力的调控,将使怒江州的生态承载力综合特征值上升8.6%.

  15. System Dynamics Simulation of Small Towns' Economy under the Constraints of Water Resources' Carrying Capacity%水资源承载力约束下小城镇经济发展的系统动力学仿真

    Institute of Scientific and Technical Information of China (English)

    卢超; 王蕾娜; 张东山; 张亚雷

    2011-01-01

    With rapid urbanization and serious water scarcity in China, carrying capacity of water resources has become an important factor affecting economic development of small towns. As the main model to simulate complex giant systems, system dynamics seems to be suitable for long-term, dynamic and macro-quantitative analysis and simulation study. According to the theory of system dynamics, exploring and applying the optimal pattern of economic growth under the constraints of water resources is the key for sustainable development. A complete small towns’ sustainable economic system includes seven sub-systems, i.e., water resources, total economic outputs, population, agriculture, industry, service industry, and ecological environment. Based on the theory dissertated above, first the authors analyzed related factors affecting water resources capacity, involving natural factors (water quantity, water quality, development and utilization levels, the availability of water resources and water self-purification capacity, ecological water requirements, and water conservation, etc) and socio-economic factors (economic scale and industrial structure, technological progress and productivity, population and living standards, market conditions, policies, regulations, psychological factors, and other resource potential, etc). Moreover, this study established a system dynamics model for coupling research on water resources and economy of small towns using Vensim PLE. As a result, the largest economic scale, the best industrial structure, and the reasonable population amounts of sustainable development can be analyzed dynamically and forecasted. Furthermore, this study selected Taipusi County, Inner Mongolia Autonomous Region as an example, which is a relative poor and seriously arid small town in middle China. Water resources are the bottleneck restricting the economic and social development of this region. The geographical boundary of this model was the administrative area

  16. Sum-capacity of Interference Channels with a Local View: Impact of Distributed Decisions

    CERN Document Server

    Aggarwal, Vaneet; Sabharwal, Ashutosh

    2009-01-01

    Due to the large size of wireless networks, it is often impractical for nodes to track changes in the complete network state. As a result, nodes have to make distributed decisions about their transmission and reception parameters based on their local view of the network. In this paper, we characterize the impact of distributed decisions on the global network performance in terms of achievable sum-rates. We first formalize the concept of local view by proposing a protocol abstraction using the concept of local message passing. In the proposed protocol, nodes forward information about the network state to other neighboring nodes, thereby allowing network state information to trickle to all the nodes. The protocol proceeds in rounds, where all transmitters send a message followed by a message by all receivers. The number of rounds then provides a natural metric to quantify the extent of local information at each node. We next study three network connectivities, Z-channel, a three-user double Z-channel and a redu...

  17. High-SIR Transmission Capacity of Wireless Networks with General Fading and Node Distribution

    CERN Document Server

    Ganti, Radha Krishna; Haenggi, Martin

    2010-01-01

    In many wireless systems, interference is the main performance-limiting factor, and is primarily dictated by the locations of concurrent transmitters. In many earlier works, the locations of the transmitters is often modeled as a Poisson point process for analytical tractability. While analytically convenient, the PPP only accurately models networks whose nodes are placed independently and use ALOHA as the channel access protocol, which preserves the independence. Correlations between transmitter locations in non-Poisson networks, which model intelligent access protocols, makes the outage analysis extremely difficult. In this paper, we take an alternative approach and focus on an asymptotic regime where the density of interferers $\\eta$ goes to 0. We prove for general node distributions and fading statistics that the success probability $\\p \\sim 1-\\gamma \\eta^{\\kappa}$ for $\\eta \\rightarrow 0$, and provide values of $\\gamma$ and $\\kappa$ for a number of important special cases. We show that $\\kappa$ is lower ...

  18. Design and evaluation on the indicator system of land comprehensive carrying capacity%土地综合承载力指标体系设计及评价——中国东部沿海地区案例研究

    Institute of Scientific and Technical Information of China (English)

    王书华; 毛汉英

    2001-01-01

    In recent years,eastern China has made great progress in economy.But with its rapid development,man land conflicts have become more and more serious. This paper,based on the review land carrying capacity,constructs a set of indicator system for comprehensive evaluation of regional land carrying capacity that can be adapted to eastern China. More over,by the use of a certain mathematical method,we can divide this region into three types according to the carrying capacity: the lower level carrying capacity subregion;the mid level carrying capacity subregion;and the higher level carrying capacity subregion. All these types stand for three steps of succession to the land carrying capacity,that is,from the harmonious step at lower level,imbalance step at middle level to the harmonious step of the advanced system.%论文在对土地承载力进行简要回顾的基础上,构建了一套适合于东部沿海地区的区域土地承载力综合评价指标体系,并运用均方差权数决策法,将该区土地承载力划分为3种类型区,即:低承载力区、中等承载力区、高承载力区,分别代表土地承载力演替从低层次的均衡发展阶段较高层次的不均衡发展阶段高层次的系统协调均衡发展阶段。

  19. 轴压加筋壁板承载能力计算方法探讨%Investigation of the Computing Methods to Calculate Load-carrying Capacity of Stiffened Panels under Axial Compression

    Institute of Scientific and Technical Information of China (English)

    王海燕; 童贤鑫

    2012-01-01

    Currently, engineering method is usually used to compute the load carrying capacity of the panels in a design process. In this paper, three major engineering methods are briefly described and investigated. These methods are evaluated through the comparison of calculated results and test data, for the stiffed panels of the central wing and fuselage of an aircraft. It is shown that the results from ultimate load method are safer and more consistent with the experimental data. The reasonable allowable stress for central wing of the aircraft is specified according to the previous comparisons and analysis. Finally, eleven types of stiffened panels under axi- al compression of the aircraft fuselage are calculated by using ultimate load method. The results agree well with the experimental data. It is approved that this method can meet the requirement more accurately and utility in engineering design.%目前飞机设计中主要采用工程方法计算加筋壁板的承载能力。本文介绍并评述了分段处理法、John-son法和极限载荷法三种常用的工程方法,为了探讨哪种方法能更加满足工程需要,采用这三种方法对某型飞机中央翼加筋壁板及其试验件分别进行计算,表明其中极限载荷法的计算结果偏于安全,与试验结果吻合较好,并采用此法确定了中央翼加筋壁板的承载能力。最后采用极限载荷法进一步计算该型飞机机身11种构型加筋壁板轴压试验件,破坏载荷计算值与试验结果相当吻合,从而证实了极限载荷法是一种计算轴压加筋壁板承载能力更准确、实用的工程方法。

  20. Optimizing Capacities of Distributed Generation and Energy Storage in a Small Autonomous Power System Considering Uncertainty in Renewables

    Directory of Open Access Journals (Sweden)

    Ying-Yi Hong

    2015-03-01

    Full Text Available This paper explores real power generation planning, considering distributed generation resources and energy storage in a small standalone power system. On account of the Kyoto Protocol and Copenhagen Accord, wind and photovoltaic (PV powers are considered as clean and renewable energies. In this study, a genetic algorithm (GA was used to determine the optimal capacities of wind-turbine-generators, PV, diesel generators and energy storage in a small standalone power system. The investment costs (installation, unit and maintenance costs of the distributed generation resources and energy storage and the cost of fuel for the diesel generators were minimized while the reliability requirement and CO2 emission limit were fulfilled. The renewable sources and loads were modeled by random variables because of their uncertainties. The equality and inequality constraints in the genetic algorithms were treated by cumulant effects and cumulative probability of random variables, respectively. The IEEE reliability data for an 8760 h load profile with a 150 kW peak load were used to demonstrate the applicability of the proposed method.

  1. General Measurement of Marine Ecological Carrying Capacity and Biological Immunology :A Case Study in Liaoning Province%基于生物免疫学理论的海域生态承载力综合测度研究——以辽宁省为例

    Institute of Scientific and Technical Information of China (English)

    狄乾斌; 吴佳璐; 张洁

    2013-01-01

    本研究根据海洋生态承载力对海洋生态系统健康的作用与人体免疫力对人体健康的维系作用的相似性,利用生物免疫学原理,构建了辽宁省海域生态承载状态综合测度指标体系,并进行了辽宁省海域2000年-2009年10年间的综合测度研究.结果表明:辽宁省海域自然承载力指数和承载力潜力指数整体分别呈下降和上升趋势,但是资源环境承载力总体却是波动下降趋势;人口与社会经济发展压力指数在2000年-2005年间波动较小,2006年呈现大幅度上升,之后稍有下降,总体上后期比前期增长较多.近几年来,辽宁省海域资源环境承载力的可持续发展状态较差,需要在海洋产业结构调整、污染治理和海洋科研方面加大力度.%Research on carrying capacity, regarded as the basis for the sustainable development of resources and the environment, is gaining more and more attention. With the growing popularity of marine issues, scholars are following the field of marine carrying capacity closely. Studies on marine carrying capacity are instrumental in planning economic development of coastal regions; however, most research findings are quantitative rather than qualitative. Because of the role of marine ecological carrying capacity in marine ecosystems is similar to the role of the human immune system in human health, we introduce a model of biological immunology using the Liaoning marine system as a case study. Numerical models such as entropy, discriminant models of sustainable development and fuzzy membership functions were used to calculate related index values. Results show that from 2000-2009 the natural carrying capacity index increased and the potential capacity index decreased, while overall carrying capacity experienced a floating decline. From 2000-2005 the pressure index of population and economic development was relatively stable, but after 2006 it encountered a sharp rise and then declined slightly with

  2. Analysis and experimental study of the temperature and stress distribution in the slab of a solid-state heat capacity laser

    Science.gov (United States)

    Yang, Jiankun; Wan, Xuebin; Xu, Xiaojun; Lu, Qisheng

    2008-03-01

    In conventional cooling operation, thermal effects and stress distribution in slabs of solid-state laser are presented by many workers, it is different with that in the solid state heat capacity laser. In this paper, the transient temperature and stress distribution in Xeon flash lamps pumped slabs for single-shot and repetitively pulsed operations will be produced in the heat capacity operation. A high speed CCD camera was used to set up an experiment system to measure the interference fringes, from these fringes' changes, the extension of the slab due to the stress and thermal expansion can be obtained. Since dielectric materials are inherently several factors stronger in compression than in tension, this temperature reversal in heat capacity operation increases the inherent fracture limit of the system and allows a heat capacity operated laser to be pumped much harder than a conventionally operated slab laser.

  3. Evaluation of Water Ecological Carrying Capacity Based on Ecological Footprint Theory: A Case Study of Huzhou%基于生态足迹法的区域水生态承载力研究——以浙江省湖州市为例

    Institute of Scientific and Technical Information of China (English)

    刘子刚; 郑瑜

    2011-01-01

    本文初步界定了水生态足迹和水生态承载力的内涵,将水生态足迹分为水产品生态足迹、水资源生态足迹与水污染生态足迹,并建立了水生态足迹模型.其中,采用了Wackemagel的水产品生态足迹模型;水资源生态足迹采用了基于水资源消耗量的计算模型;采用零维模型计算污染稀释净化需水量,构建水污染生态足迹模型.最后,以扣除60%生态需水为前提建立了水生态承载力计算模型.以浙江省湖州市为例,模型计算了湖州市2000年-2007年水生态足迹和水生态承载力,结果显示,湖州市2000年-2007年水生态承载力超过水生态足迹,呈现生态盈余,但是水生态承载力波动较大,水生态足迹在不断增大;由于水产品的消费量逐年增大,水产品生态足迹在水生态足迹中所占比例也相应增大.%Ecological footprint is widely used in many countries and regions and has become an important method to evaluate ecological carrying capacity. Based on the ecological footprint model, an evaluation model on water ecological carrying capacity was built and was used to assess water ecological carrying capacity in Huzhou City, Zhejiang Province. The concept of water ecological carrying capacity was defined. Water ecological carrying capacity consists of water product footprint, water resource footprint, and water pollution footprint. The original model raised by Wackemagel was used to calculate water product footprint. Water resource footprint was divided into four third level accounts, i.e., agriculture water footprint, industrial water footprint, domestic water footprint, and other water footprint. Besides, based on the ecological footprint model, the zero-dimensional model was used to calculate water demand of pollution dilution and purification and then water pollution footprint was calculated. At last, a water carrying capacity model was built on the basis of 60% of all the water resource being necessary to

  4. 中国土壤有效含水量分布%Distribution of available soil water capacity in China

    Institute of Scientific and Technical Information of China (English)

    周文佐; 刘高焕; 潘剑君

    2005-01-01

    The available soil water capacity (ASWC) is important for studying crop production,agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for most of soil profiles and the nationwide ASWC largely remains lacking in relevant soil data in China. This work was to estimate ASWC based on physical and chemical properties and analyze the spatial distribution of ASWC in China. The pedo-transfer functions (PTFs), derived from 220 survey data of ASWC, and the empirical data of ASWC based on soil texture were applied to quantify the ASWC. GIS technology was used to develop a spatial file of ASWC in China and the spatial distribution of ASWC was also analyzed. The results showed the value of ASWC ranges from 15 × 10-2 cm3·cm-3 to 22 × 10-2 cm3·cm-3 for most soil types, and few soil types are lower than 15 × 10-2 cm3·cm-3 or higher than 22 × 10-2 cm3·cm-3. The ASWC is different according to the complex soil types and their distribution. It is higher in the east than that in the west, and the values reduce from south to north except the northeastern part of China. The "high" values of ASWC appear in southeast, northeastern mountain regions and Northeast China Plain. The relatively "high" values of ASWC appear in Sichuan basin, Huang-Huai-Hai plain and the east of Inner Mongolia. The relatively "low" values are distributed in the west and the Loess Plateau of China. The "very low" value regions are the northern Tibetan Plateau and the desertified areas in northern China. In some regions, the ASWC changes according to the complex topography and different types of soils. Though there remains precision limitation, the spatial data of ASWC derived from this study are improved on current data files of soil water retention properties for Chinese soils. This study presents basic data and analysis methods for estimation and evaluation of ASWC in China.

  5. Body temperature null distributions in reptiles with nonzero heat capacity: seasonal thermoregulation in the American alligator (Alligator mississippiensis).

    Science.gov (United States)

    Seebacher, Frank; Elsey, Ruth M; Trosclair, Phillip L

    2003-01-01

    Regulation of body temperature may increase fitness of animals by ensuring that biochemical and physiological processes proceed at an optimal rate. The validity of current methods of testing whether or not thermoregulation in reptiles occurs is often limited to very small species that have near zero heat capacity. The aim of this study was to develop a method that allows estimation of body temperature null distributions of large reptiles and to investigate seasonal thermoregulation in the American alligator (Alligator mississippiensis). Continuous body temperature records of wild alligators were obtained from implanted dataloggers in winter (n=7, mass range: 1.6-53.6 kg) and summer (n=7, mass range: 1.9-54.5 kg). Body temperature null distributions were calculated by randomising behavioural postures, thereby randomly altering relative animal surface areas exposed to different avenues of heat transfer. Core body temperatures were predicted by calculations of transient heat transfer by conduction and blood flow. Alligator body temperatures follow regular oscillations during the day. Occasionally, body temperature steadied during the day to fall within a relatively narrow range. Rather than indicating shuttling thermoregulation, however, this pattern could be predicted from random movements. Average daily body temperature increases with body mass in winter but not in summer. Daily amplitudes of body temperature decrease with increasing body mass in summer but not in winter. These patterns result from differential exposure to heat transfer mechanisms at different seasons. In summer, alligators are significantly cooler than predictions for a randomly moving animal, and the reverse is the case in winter. Theoretical predictions show, however, that alligators can be warmer in winter if they maximised their sun exposure. We concluded that alligators may not rely exclusively on regulation of body temperature but that they may also acclimatise biochemically to seasonally

  6. Modeling Mental Speed: Decomposing Response Time Distributions in Elementary Cognitive Tasks and Correlations with Working Memory Capacity and Fluid Intelligence

    Directory of Open Access Journals (Sweden)

    Florian Schmitz

    2016-10-01

    Full Text Available Previous research has shown an inverse relation between response times in elementary cognitive tasks and intelligence, but findings are inconsistent as to which is the most informative score. We conducted a study (N = 200 using a battery of elementary cognitive tasks, working memory capacity (WMC paradigms, and a test of fluid intelligence (gf. Frequently used candidate scores and model parameters derived from the response time (RT distribution were tested. Results confirmed a clear correlation of mean RT with WMC and to a lesser degree with gf. Highly comparable correlations were obtained for alternative location measures with or without extreme value treatment. Moderate correlations were found as well for scores of RT variability, but they were not as strong as for mean RT. Additionally, there was a trend towards higher correlations for slow RT bands, as compared to faster RT bands. Clearer evidence was obtained in an ex-Gaussian decomposition of the response times: the exponential component was selectively related to WMC and gf in easy tasks, while mean response time was additionally predictive in the most complex tasks. The diffusion model parsimoniously accounted for these effects in terms of individual differences in drift rate. Finally, correlations of model parameters as trait-like dispositions were investigated across different tasks, by correlating parameters of the diffusion and the ex-Gaussian model with conventional RT and accuracy scores.

  7. 阿尔金山自然保护区基于野牦牛、藏野驴、藏羚羊适宜栖息地的生态容量估测%Estimation of ecological carrying capacity for wild yak, kiang, and Tibetan antelope based on habitat suitability in the Aerjin Mountain Nature Reserve, China

    Institute of Scientific and Technical Information of China (English)

    董世魁; 翁晋; 武晓宇; 刘世梁; 苏旭坤; 吴娱; 石建斌; 李晓文; 张翔; 许东华

    2015-01-01

    National Nature Reserve ( AMNNR) on the Qinghai-Tibetan Plateau, China, is a major refuge for three wild ungulates;wild yak ( Bos mutus) , kiang ( Equus kiang) , and Tibetan antelope ( Pantholops hodgsoni) . This nature reserve is important for conserving these three wild endemic ungulates and their habitats. Over decades of conservation, the populations of these three ungulates have increased rapidly. However, the administrators of AMNNR considered that the kiang might have become overpopulated, which would result in habitat degradation. Thus, it is vital implement wildlife management planning based on the quantification of ecological carrying capacity for sustainable nature reserve management. In this study, vehicular transects were conducted to survey the distribution data and record the populations of wild yak, kiang, and Tibetan antelope from May to June, 2012, and June to July, 2013, in the AMNNR. We integrated remote sensing data analysis with on-the-ground plot surveys to identify suitable habitats ( alpine steppe, alpine desert steppe, alpine desert, and alpine meadow) for all three ungulates, and we estimated habitat production. A dietary analysis of wild yak, kiang, and Tibetan antelope was completed to estimate the amount of edible grasses required for the three wild ungulates in suitable habitats. Using the empirical formula ( calculation of the proper carrying capacity of rangelands) provided by the PRC Ministry of Agriculture, we quantified the carrying capacity for all three species in suitable habitats and in the whole natural reserve. The results showed that areas of suitable habitat for wild yak, kiang, and Tibetan antelope were 31866. 07 km2 , 24035. 51 km2 , and 24035. 51 km2 , respectively. There were big overlaps in the suitable habitats for all three wild ungulates, which shared almost the same suitable habitats. Within the suitable habitats, alpine steppe, alpine desert steppe, alpine desert, and alpine meadow could potentially provide 3944.91

  8. 黑河流域2004—2010年水足迹和水资源承载力动态特征分析%Dynamic Characteristics of Water Footprint and Water Resources Carrying Capacity in Heihe River Basin during 2004-2010

    Institute of Scientific and Technical Information of China (English)

    张军; 周冬梅; 张仁陟

    2012-01-01

    China is facing serious water resources problems such as shortage in volume and uneven distribution in space and time.In the typical Heihe River basin in northwest China,water resources problems are restricting its social and economic development.With the Ecological Footprint Model we constructed five water resources accounts,they are agriculture water,urban public water,industrial water,domestic water,and eco-environmental water;and calculated and analyzed the water resources carrying capacity,water footprint and load situation of water resources in the Heihe River basin during 2004-2010.Results showed that the water resources carrying capacity gradually increased from 16.36 hm2 to 24.40 hm2;agriculture water footprint decreased from 541.48 hm2 to 443.65 hm2,industrial water footprint increased from 19.11 hm2 to 22.95 hm2,domestic water footprint increased from 10.85 hm2 to 14.93 hm2,urban public water footprint increased from 2.75 hm2 to 3.28 hm2 and eco-environmental water footprint increased from 0.37 hm2 to 5.19 hm2 during 2004-2010,and the total water resources ecological footprint gradually decreased from 571.81 hm2 to 486.73 hm2;water resources ecological deficit decreased from 555.45 hm2 to 462.33 hm2;and load index of water resources increased from 9.62 to 12.11 during 2004-2010.The load index of water resources is high and the exploitation potential is low in the Heihe River basin.The water resources carrying capacity is related with precipitation.%中国是水资源短缺国家,水资源时空分布不均,水资源已成为制约中国社会经济可持续发展的重要因素。利用生态足迹法构建了黑河流域农业用水、工业用水、城镇公共用水、生活用水和生态环境用水5个二级水资源账户,并利用水资源负载指数,研究了黑河流域2004—2010年水资源承载力、水足迹和水资源负载动态特征。结果表明,黑河流域水资源承载力从2004年的16.36hm2增加至2010年的24.40hm2;

  9. Dynamics of phytoplankton distribution and photosynthetic capacity in a western Norwegian fjord during coastal upwelling: Effects on optical properties

    Science.gov (United States)

    Erga, Svein Rune; Ssebiyonga, Nicolausi; Frette, Øyvind; Hamre, Børge; Aure, Jan; Strand, Øivind; Strohmeier, Tore

    2012-01-01

    The present study describes the coupling between optical properties and the dynamics of phytoplankton distribution and photosynthetic capacity in the Lysefjord during an exceptional coastal upwelling. At the mouth of the fjord, transparent Coastal water was "piled up" against the sill, while more turbid Fjord water from the outer fjord system was flowing over the sill, creating the intermediate layer which extended further into the fjord. This was reflected by high spectral attenuation coefficients in the upper 10 m of the fjord. Outside the sill, clear water with low spectral attenuation coefficients were found below sill depth down to at least 30 m, while the attenuation coefficients inside the sill were significantly higher between 10 and 20 m. About 4-7 km outwards from the head of the fjord clearer deep basin water was entering the upper layer due to the upwelling which could be traced up to 7 m, bounded by the 7.5 °C and the 31 salinity isolines. In the outer part of the fjord waters with a high chl a content and photosynthetic capacity were observed below the outflowing surface layer containing "old water" from the inner part of the fjord, which was characterized by low nutrient and chl a concentrations. Maximum quantum efficiencies (0.5) were encountered within this subsurface layer. Quantum efficiencies exceeded 0.3 when nitrate and silicate concentrations increased above 2 mmol m -3. About 50% of the PAR light attenuation (0-30 m) was caused by chl a, and the 1% light depth varied between 27 and 35 m along the transect. Due to the influence of freshwater outlets, non-pigmented particles were more abundant in the inner part of the fjord than in the outer part. Colored dissolved organic matter (CDOM) contributed strongly to absorption within the upper 10 m at wavelengths below 470 nm while scattering was the major attenuation contributor for wavelengths above 600 nm. With respect to possible climate change effects on the growth of phytoplankton in

  10. Distribution of synapses on two ascending interneurones carrying frequency-specific information in the auditory system of the cricket: evidence for GABAergic inputs.

    Science.gov (United States)

    Hardt, M; Watson, A H

    1994-07-22

    Two identified cricket auditory interneurones, AN1 and AN2, were intracellularly labelled with horseradish peroxidase following physiological characterisation. The neurones, which have some structural similarities, have their somata in the prothoracic ganglion and axons that project to the brain. Although both carry auditory information, they have different response properties and participate in different types of phonotactic behaviour. Ultrathin sections from selected regions of their prothoracic arborisations were examined in the electron microscope after postembedding immunostaining for the inhibitory transmitter GABA. In the prothoracic ganglion AN1 branches only in the medial ventral association centre (mVAC) contralateral to the soma, and receives only iput synapses. Twenty-seven percent of these were made by processes immunoreactive for GABA. AN2 branches not only in mVAC on both sides of the ganglion but also in several other areas. It makes output synapses from large diameter neurites in mVAC on both sides of the ganglion as well as from neurites in more posterior regions of the neuropile. Most input synapses are received onto branches in the contralateral mVAC where about 19% were made from GABA-immunoreactive processes.

  11. Capacity Remuneration Mechanisms for Reliability in the Integrated European Electricity Market: Effects on Welfare and Distribution through 2023

    DEFF Research Database (Denmark)

    Traber, Thure

    2017-01-01

    A reduced attractiveness of investments in reliable fossil power plants in liberalized markets on the background of a transition towards renewable energies has brought a discussion on capacity policies to Europe. I develop a partial equilibrium model to compare effects of three polar capacity...

  12. About rats and jackfruit trees: modeling the carrying capacity of a Brazilian Atlantic Forest spiny-rat Trinomys dimidiatus (Günther, 1877) – Rodentia, Echimyidae – population with varying jackfruit tree (Artocarpus heterophyllus L.) abundances

    OpenAIRE

    Mello,JHF; Moulton,TP; Raíces,DSL; Bergallo,HG.

    2015-01-01

    We carried out a six-year study aimed at evaluating if and how a Brazilian Atlantic Forest small mammal community responded to the presence of the invasive exotic species Artocarpus heterophyllus, the jackfruit tree. In the surroundings of Vila Dois Rios, Ilha Grande, RJ, 18 grids were established, 10 where the jackfruit tree was present and eight were it was absent. Previous results indicated that the composition and abundance of this small mammal community were altered by the presence and d...

  13. 分布式MIMO系统的复合信道容量分析%Capacity analysis of compound channel for distributed MIMO system

    Institute of Scientific and Technical Information of China (English)

    刘伟; 汪清

    2013-01-01

    Distributed MIMO system combines the characteristics of MIMO channel and distributed antenna system, which is believed a very promising technology in the future of 4G, because of its large capacity, large coverage and less power loss from shadow and distance. A compound channel model considering path loss, lognormal shadow fading and small scale fading for distributed MIMO system model is adopted, the capacity of which is analyzed. Besides channel capacity between distributed MIMO system and centralized MIMO system is compared by Monte Carlo simulations. At the same time, the impact of spatial fading correlation and path loss on the capacity is also investigated. The simulation results prove that distributed MIMO system can effectually reduce the impact of small scale fading, and achieve a better channel capacity.%分布式MIMO系统结合了MIMO技术和分布式天线系统两者的特点,具有高容量、大覆盖范围、低损耗的优势,在未来4G通信中具有很好的应用前景.基于包含了路径损耗、阴影衰落和相关小尺度衰落的分布式MIMO信道模型,通过Monte Carlo仿真比较分析了分布式MIMO系统和集中式MIMO系统的信道容量,研究了空间相关性和路径损耗对信道容量的影响.仿真实验结果表明,分布式MIMO系统能有效降低小尺度衰落相关性的影响,可以获得更好的平均信道容量.

  14. Average capacity of the ground to train communication link of a curved track in the turbulence of gamma-gamma distribution

    Science.gov (United States)

    Yang, Yanqiu; Yu, Lin; Zhang, Yixin

    2017-04-01

    A model of the average capacity of optical wireless communication link with pointing errors for the ground-to-train of the curved track is established based on the non-Kolmogorov. By adopting the gamma-gamma distribution model, we derive the average capacity expression for this channel. The numerical analysis reveals that heavier fog reduces the average capacity of link. The strength of atmospheric turbulence, the variance of pointing errors, and the covered track length need to be reduced for the larger average capacity of link. The normalized beamwidth and the average signal-to-noise ratio (SNR) of the turbulence-free link need to be increased. We can increase the transmit aperture to expand the beamwidth and enhance the signal intensity, thereby decreasing the impact of the beam wander accordingly. As the system adopting the automatic tracking of beam at the receiver positioned on the roof of the train, for eliminating the pointing errors caused by beam wander and train vibration, the equivalent average capacity of the channel will achieve a maximum value. The impact of the non-Kolmogorov spectral index's variation on the average capacity of link can be ignored.

  15. Probability Distribution of Airport Capacity Affected by Weather%天气影响的机场容量概率分布

    Institute of Scientific and Technical Information of China (English)

    张静; 徐肖豪; 王飞

    2011-01-01

    Weather is a major factor causing airport capacity reduction. To reflect the impact of the weather on capacity, the n-phase arrival capacity distribution model is established. The historical weather data are translated into the capacity probability distribution for each weather type through weather type decision tree. According to the capacity probability distribution of each weather type, the probabilistic weather forecasts are translated into probabilistic capacity forecasts by using total probability formula. Weather forecasts of a day are simulated according to the 5-year airport hourly data, and a set of the n-phase arrival capacity distribution based on the weather forecasts is obtained. Simulation results indicate that inclement weather forecasts at different time can be translated into a set of stochastic capacity forecasts, which thus meeting the needs of the real time traffic flow management.%天气是影响机场容量下降的主要因素,为了反映预测天气对容量的影响,建立了n-阶段到达容量分布模型.通过天气类型决策树将历史天气数据转换为每种天气类型的到达容量概率分布.根据天气类型的容量概率分布,用全概公式将概率天气预测转换为概率容量预测.基于5年的机场小时天气数据,对某一日的预测天气进行算例仿真,得到了一组基于预测天气的n-阶段容量概率分布.结果表明,n-阶段容量分布模型能够将机场不同时段的预测恶劣天气转换为预测随机容量,从而满足实时流量管理的需要.

  16. 基于供电能力分析的高压配电线路容量优化方法%Capacity Optimization of HV Distribution Lines Based on Load Supply Capability Analysis

    Institute of Scientific and Technical Information of China (English)

    葛少云; 郭寅昌; 刘洪

    2014-01-01

    To reasonably choose current-carrying capacities of HV distribution lines to implement refined planning and intensive construction to select benefiting conductors to reduce invest and increase utilization of supplying equipment, a method to optimize capacity of HV distribution line based on load supply capability analysis is proposed. Firstly, the concepts of power supplying route matrix and operation/wheeling mode vector of main transformer are defined to describe the information of the wireframe of HV distribution network; then based on the analysis of load supply capability of distribution network the minimized demand on capacity of HV distribution line, which makes the load supplying capability of distribution network reaching its limit, is taken as the objective and the constraints are determined through the analysis on normal operation of HV distribution wireframe and N-1 contingency as well as the analysis on operation/wheeling mode and the loop closing of wheeling mode, and then a mathematical model is formed;finally, a modified genetic algorithm is presented and used to solve the proposed optimization model. The effectiveness and practicality of the proposed method are verified by the calculation of a certain urban distribution network.%为合理选择高压配电线路载流量以实现高压配电网精细化规划和集约型建设,提出一种基于供电能力分析的高压配电线路容量优化方法。首先定义供电路径矩阵和运行/转供方式向量来描述高压配电网网架信息;然后基于配电网供电能力分析,以使配电网供电能力达到极限的最小高压配电线路容量需求为目标,通过配电网高压网架正常运行分析、高压配电线路N-1校验分析以及高压网架运行/转供方式和转供方式的合环情况分析建立约束,最终形成数学模型;最后提出一种改进的遗传算法对模型进行求解。通过某城区电网实例计算证明了算法的有效性和实用性。

  17. Extracting Soil Water Holding Capacity Parameters of a Distributed Agro-Hydrological Model from High Resolution Optical Satellite Observations Series

    Directory of Open Access Journals (Sweden)

    Sylvain Ferrant

    2016-02-01

    Full Text Available Sentinel-2 (S2 earth observation satellite mission, launched in 2015, is foreseen to promote within-field decisions in Precision Agriculture (PA for both: (1 optimizing crop production; and (2 regulating environmental impacts. In this second scope, a set of Leaf Area Index (LAI derived from S2 type time-series (2006–2010, using Formosat-2 satellite is used to spatially constrain the within-field crop growth and the related nitrogen contamination of surface water simulated at a small experimental catchment scale with the distributed agro-hydrological model Topography Nitrogen Transfer and Transformation (TNT2. The Soil Water Holding Capacity (SWHC, represented by two parameters, soil depth and retention porosity, is used to fit the yearly maximum of LAI (LAX at each pixel of the satellite image. Possible combinations of soil parameters, defining 154 realistic SWHC found on the study site are used to force spatially homogeneous SWHC. LAX simulated at the pixel level for the 154 SWHC, for each of the five years of the study period, are recorded and hereafter referred to as synthetic LAX. Optimal SWHCyear_I,pixel_j, corresponding to minimal difference between observed and synthetic LAXyear_I,pixel_j, is selected for each pixel, independent of the value at neighboring pixels. Each re-estimated soil maps are used to re-simulate LAXyear_I. Results show that simulated and synthetic LAXyear_I,allpixels obtained from SWHCyear_I,allpixels are close and accurately fit the observed LAXyear_I,allpixels (RMSE = 0.05 m2/m2 to 0.2 and R2 = 0.99 to 0.94, except for the year 2008 (RMSE = 0.8 m2/m2 and R2 = 0.8. These results show that optimal SWHC can be derived from remote sensing series for one year. Unique SWHC solutions for each pixel that limit the LAX error for the five years to less than 0.2 m2/m2 are found for only 10% of the pixels. Selection of unique soil parameters using multi-year LAX and neighborhood solution is expected to deliver more robust soil

  18. 热轧高强度钢压杆的承载能力分析%Analysis of the Load-Carrying Capacity of Hot-Rolled High-Strength Steel Struts

    Institute of Scientific and Technical Information of China (English)

    陈绍蕃; 申红侠

    2011-01-01

    现行钢结构设计规范的一些规定不利于充分发挥高强度钢压杆的潜力.热轧型钢的残余应力和钢材的强度等级无关,因而它对高强度钢压杆的不利效应低于Q235钢.本文基于这一认知进行了承载力分析,提出了改进稳定系数取值的两种方案,可使高强度钢压杆设计得更为合理.%Some provisions of the current Code for Design of Steel Structures are unfavourable for high-strength steel struts to fully develop their inherent potential. The magnitude of residual stress in hot-rolled shapes is independent of the strength grade of the steel. So, its detrimental effect is smaller to high-strength struts than to Q235 ones. Based on this knowledge, analysis of bearing capacity has been performed and two approaches of improving the stability strength coefficient are presented which may lead to more rational design of high-strength steel struts.

  19. Research of the Tourism Destination Carrying Capacity---A Case Study of the Ancient City of Kaifeng Song Du Cultural Industry Park%旅游目的地容量测量研究--以开封宋都古城文化产业园区为例

    Institute of Scientific and Technical Information of China (English)

    孙慧娟

    2016-01-01

    随着旅游市场的快速发展和游客出游的不断增加,过多游客的涌入、景区超载拥堵现象不断出现。旅游容量作为旅游目的地规划开发的科学依据和景区管理的工具,其研究成为一个重要课题。依据木桶原理及限制性因子原理,选取空间容量、设施容量、生态容量和社会心理容量等作为旅游地容量指标,构建综合容量测量模型。以开封宋都古城文化产业园区为例,选取基本空间标准,分析得出产业园区日旅游容量为190484人次,年旅游容量69526660人次,并对产业园区旅游发展提出建议。%With the rapid development of the tourism market and the increasing of tourists ,the influx of too many tourists 、the scenic spots overload and congestions phenomenons appear constantly .Tourism carrying capacity is a scientific basis of tourism destination planning development and a tool of the scenic area management ,soit has become an important subject .Based on buckets effect and the principle of limiting factors , this paper selects space capacity , facilities capacity,ecological capacity and social psychological capacity as the basic indexes of tourism carrying capacity , and constructs comprehensive capacity measurement model.Then,this paper takes the ancient city of Kaifeng Song Du cultural industry park as an example,and selects basic space standards,analyzes and concludes that the tourism carrying capacity of industry park is 190484 person/time every-day,69526660 person/time every year,finally puts forward the proposal on its tourism development .

  20. 塔里木河流域基于资源环境水价的农业水价的承受力分析%An Analysis of the Farmers Carrying Capacity of the Future Agricultural Water Prices Based on the Resourceful and Environmental Water Prices in the Tarim River Basin

    Institute of Scientific and Technical Information of China (English)

    孙建光; 韩桂兰

    2012-01-01

    首先在成本水价基础上,分别构建塔河流域作物和流域基于水资源费的未来农业水价,然后进一步;E总和计算了塔河流域农户对基于资源环境水价的未来农业水价的承受力分析的基本指标;在此基础上,分析了塔河流域农户对基于资源环境水价的未来农业水价的承受力,主要结果表明:除叶尔羌河、和田河流域和干流下游基于资源环境水价的未来流域和作物水价的农户承受力超过适宜经济承受力外,其他源流和干流上中游的农户水价承受力则处于适宜经济承受力范围,未来塔河流域应当实行差别水价政策;干流下游、叶尔羌河流域未来农业水价承受力很低,尤其是流域未来粮食作物水价的承受力很低,必须给予粮食作物农业水价直接补偿。而且,环境水价对农户水价承受力影响较小,能够成为未来流域生态环境保护的主要经济手段。%Based on the water price of the cost, the future agricultural water price on the basis of water resources fee and the future agricultural water price based on water resources fee and environmental water price are determined in the Tarim River Basin; then the basic index of farmers" carrying capacity of the future agricultural water price are calculated according to them, this paper analyzes the farmers" carrying capacity of the future agricultural water prices based on water resources fee and environmental water prices in the Tarim River Basin, the results indicate that besides farmers' carrying capacity of the future agricultural water price based on water re- sources fee and environmental water prices is beyond the suitable scope of farmers" carrying capacity in theYerqiang River Basin, He- tian River Basin and the low part of the Tarim River, the other basin is lower than the suitable scope of farmerg carrying capacity. The water policy should be carried out to use different water prices

  1. 碳纤维加固钢-混凝土组合梁承载力极限状态计算%Analysis of Ultimate Load-carrying Capacity of Strengthening Steel-concrete Composite Beam Using Carbon Fiber

    Institute of Scientific and Technical Information of China (English)

    荣学亮; 黄侨

    2011-01-01

    Carbon fiber is a kind of optimal materials for bridge maintenance and reinforcement. Design method of strengthening steel-concrete composite bridges using carbon fiber was studied. Characteristic of bridge reinforce-ment under load and phasing of stress features were considered, and calculation method of ultimate limit state was suitable for existing bridge design code . Ultimate strain of carbon fiber in ultimate limit state is firstly established based on plane-section assumption and strain-lag of carbon fiber. Then computational scheme and calculation meth-od of flexural capacity in positive moment area and negative moment area for strengthening steel-concrete composite beam using carbon fiber are established respectively, which is reference for design of bridge strengthening.%碳纤维复合材料是进行桥梁维修和加固的理想材料.对采用碳纤维复合材料加固钢-混凝土组合梁桥的设计方法进行了分析.考虑桥梁结构带载加固分阶段受力的特点,与现行桥梁设计规范中承载能力极限状态计算方法相适应.首先基于平截面假设和碳纤维应变滞后的特点,确定承载能力极限状态下碳纤维片材的极限应变值.然后分别建立了碳纤维片材加固钢-混凝土组合梁在正弯矩区和负弯矩区抗弯承载力的计算图式和计算方法,可供桥梁加固工程设计参考.

  2. Analysis of Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    孙淑珍

    2004-01-01

    Chapter Ⅰ Introduction  Sitting in the rocking chair,Carrie dreams her future.This is the deep impression the novel"Sister Carrie"gives us,which is written by Theodore Dreiser(1871-1945),the great American realism writer.  ……

  3. The geograpy of the Spanish airport system: spatial concentration and deconcentration patterns in seat capacity distribution, 2001-2008

    NARCIS (Netherlands)

    P. Suau-Sanchez; G. Burghouwt

    2011-01-01

    This paper analyzes the geography of seat capacity at Spanish airports between 2001 and 2008. Concentration and deconcentration patterns for different markets have been identified. For this purpose, we use the Herfindahl-Hirschman Index (HHI), the Concentration Ratio (CR) and the Lorenz curve. From

  4. Ecological Territory New Research Perspectives for the Urban Ecological Carrying Capacity%生态版图——城市生态承载力研究的新视角

    Institute of Scientific and Technical Information of China (English)

    覃盟琳; 吴承照

    2011-01-01

    城市生态版图是城市发展消费的各种生态系统服务在地球表层形成的空间格局,心距是城市生态版图的主要度量指标,城市生态版图空间结构变化会影响到城市的生态效率、生态质量、生态安全、生态公平.城市生态版图是城市生态足迹空间分布格局的理论概括,城市生态版图边界是动态的,超越城市行政边界.比较义乌和南充两个城市的生态版图,获得义乌生态效率比南充低、义乌城市生态质量好转而南充恶化、义乌存在生态安全隐患、义乌城市发展模式加剧区域生态公平失衡等结论.基于生态版图理论的城市发展策略包括土地、空间、人口、生态补偿等4个方面的策略.%The urban ecological territory is the spatial pattern of ecosystem services that supplies ecological resources for urban development. The five factors, namely the ecological efficiency, the ecological quality, the ecological security, the ecological fairness, and the ecological service distance, are the main parameters of an urban ecological territory. The urban ecological territory is a theoretical concept of spatial distribution pattern of the urban ecological foot-print, and the boundary of urban ecological territory is dynamic, which is different from the boundary of urban administration.Based on a comparison between the ecological territories of Yiwu city and Nanchong city, the paper suggests that the distance of ecological services immediately influences the transportation cost of ecological resources. That is, the longer the ecological service distance, the lower the urban ecological efficiency. Ecologically, Yiwu city is invasive while Nanchong city is the opposite. The ecosystem of Yiwu city is abundant with positive ecological reserve rate . The ecosystem of Nanchong city is coercive with negative ecology reserve rate. Based on ecological territory theory, urban development strategies should includes several aspects

  5. On-road-vehicle carrying capacity for urban transport management——Taking Wuhan for example%基于在驶量环境承载力的城市交通管理——以武汉市为例

    Institute of Scientific and Technical Information of China (English)

    王真; 许翠琳; 王亮

    2012-01-01

    As a part of urban complex ecological system,urban traffic system function as the "blood system" of a city.The traffic carrying capacity could influence the urban development and living environment.This paper introduces an on-road-vehicle carrying capacity model based on road,energy and atmospheric environment analysis.And it has applied to Wuhan.The results show that the maximum on-road-vehicle is 407 thousand in Wuhan within the limitation of road,energy and air quality;NOx capacity is the main limit of the transportation system in Wuhan.%城市交通系统是城市复合生态系统中的一部分,城市交通承载力的大小影响城市发展的速度与生活环境.构建了由路网资源、燃油供给和大气环境模块组成的基于"在驶量承载力"的城市交通承载力宏观定量模型,并选择武汉市城区作为案例.研究得到2009年武汉市城区交通承载力为40.7万辆,NOx容量是制约武汉市未来交通发展的主要限制因子.

  6. 高强冷弯薄壁型钢抱合箱形截面受压构件承载力试验研究%Load-carrying capacity of 550MPa high-strength cold-formed thin-walled steel built-up box section columns

    Institute of Scientific and Technical Information of China (English)

    李元齐; 姚行友; 沈祖炎; 王树坤; 刘翔

    2011-01-01

    由两个槽形截面构成的抱合箱形截面在超薄壁冷弯型钢结构中应用广泛,但关于其承载力的计算只是将单个构件的承载力简单地数学叠加,并没有相应公式来考虑单个槽形截面构件之间的相互加强.对40根高强冷弯薄壁型钢抱合箱形截面受压构件进行试验研究,考察其受力特性及破坏特征,包括轴压构件21个,绕弱轴偏心和绕强轴偏心构件共19个.试验研究结果表明:抱合箱形截面构件由于两个槽形截面试件的相互约束作用,实测承载力比按单根构件计算承载力叠加结果提高10%~20%左右.最后,在试验和理论分析的基础上,针对高强冷弯薄壁型钢抱合箱形截面受压构件极限承载力提出了一种建议计算方法,依照建议计算方法所得结果与试验结果吻合较好,且偏于安全,可供实际设计参考.%Built-up box section columns by two lipped channel sections are widely used in super thin-walled cold-formed steel structures.However, for their load-carrying capacities of built-up box section columns, usually a mathematical sum according to the load-carrying capacities of each channel section involved is utilized without any further consideration on the reinforcement between single channel sections.Load-carrying capacities and failure modes of 40 high-strength cold-formed thin-walled steel built-up box section columns have been studied, including 21 axially-compressed columns and 19 eccentrically-compressed columns subjected to bending moments along the weak axis and the strong axis respectively.The results show that, due to the interaction between two lipped channel columns connected by self-drilling screws, the ultimate load-carrying capacity of a built-up box section column is 10% to 20% higher than the sum of the ultimate load-carrying capacity of two single lipped channels loaded in the same way independently.Based on the tests and theoretical analysis, a proposed method to estimate

  7. 后发地区生态承载力及其评价方法研究——以海峡西岸经济区为例%Ecological Carrying Capacity and Its Assessment Method in Late-Developing Regions——A Case Study in the Economic Zone on the West Side of the Straits

    Institute of Scientific and Technical Information of China (English)

    赵卫; 沈渭寿; 张慧; 孙明; 孙俊

    2011-01-01

    在区域生态承载力及其与资源、环境承载力相互关系的基础上,针对后发地区敏感的生态环境、强烈的发展愿景和以产业区域转移为主的后发优势战略,阐明了后发地区生态承载力的判定标准和衡量对象,构建了后发地区生态承载力概念模型;与区域生态系统健康评价相结合,运用多目标规划,建立了后发地区生态承载力评价模型,对海峡西岸经济区生态承载力进行了综合评价。目前海西区生态系统所承受的人类干扰总体上较轻,重点产业发展尚未对区域生态系统的结构、功能和健康等级构成威胁。若海西区土地产出率升至2007年上海市土地产出率的75%,海西区及其多数分区生态系统可以持续支撑其重点产业中长期发展。海西区生态系统的承载能力和承载状况具有显著的区域差异,有利于该地区经济社会的健康发展、生态服务功能的持续发挥和区域生态安全的有效保障。%Based on ecological carrying capacity and the relationship between ecological carrying capacity and other carrying capacity,the judgment standard and measurement object of ecological carrying capacity in late-developing regions were defined,the conceptual model of ecological carrying capacity in late-developing regions was also built,according to their sensitive eco-environment,relative slowness of socio-economic development,strong aspiration of development and late-developing strategy.The assessment method of ecological carrying capacity in late-developing regions was also established by multi-objective programming,combining with regional ecosystem health assessment.A case study was carried out in the economic zone on the west side of the Straits(called "Haixi Zone" for short),aiming at the sustainable development of key industry.Results showed that the human disturbance index of Haixi Zone was 2.68% in 2007,which is lower than the average level(3.13%) of China

  8. Sister Carrie in China

    Institute of Scientific and Technical Information of China (English)

    殷希

    2015-01-01

    Sister Carrie has received many Chinese scholar's attention, and it has quantity relevance researches. Therefore, it is valuable to study why it is popular in China and it's education meaning for Chinese people. In addition, to analysis the domestic re-searches and find it's exist problems can help us make a new breakthrough from the study.

  9. Research on load-carrying capacity of 2-DOF RR&PRR decoupled spherical parallel mechanisms based on performance atlas%基于性能图谱的2自由度RR&PRR解耦球面并联机构承载能力研究

    Institute of Scientific and Technical Information of China (English)

    曲云霞; 李为民; 高瑞廷; 范顺成

    2012-01-01

    2自由度解耦球面并联机构动平台通过两条支链与静平台连接,第1条支链由两个转动副(R)组成,第2条支链由1个移动副(P)、2个转动副(R)组成.在机构设计无量纲法建立2自由度解耦球面并联机构空间模型的基础上,对该机构的承载能力性能指标进行系统的分析,提出了应用性能指标均值及其波动情况描述机构承载能力性能的新方法,以等值线的形式绘制了该机构的承载能力性能图谱.%The moving platform of a 2-DOF RR&PRR decou-pled spherical parallel mechanism is connected with static platform by two legs in parallel. The first leg is composed of two revolute joints (R). The second leg is composed of one prismatic pair (P) and two revolute joints ( R). Based on the spatial model of RR&PRR mechanism established by employing the non-dimensional method, the performance indexes of load-carrying capacity for this mechanism were analyzed systematically. A novel method to de-scribe the mechanisms load-carrying capacity performances by using the mean value of performance indexes and its fluctuation was pro-posed was proposed. The performance atlas of load-carrying capaci-ty was drawn in the form of contour series.

  10. 国内外资源环境承载力模型和评价方法综述--基于内容分析法%Reviews on Resources and Environment Carrying Capacity Model and Evaluation Methods Both in China and Abroad-Based on Content Analysis

    Institute of Scientific and Technical Information of China (English)

    李华姣; 安海忠

    2013-01-01

    采用内容分析法,对国内外1991到2012年间资源环境承载力相关文献进行研究。通过搜索CNKI以及SCI和SSCI数据库,共检索并筛选得到资源环境承载力相关论文978篇(其中CNKI文献857篇,SCI、SSCI文献121篇)作为本次研究的对象。综合分析国内外承载力文献所构建和使用的模型和评价方法,其研究特点和发展趋势:从定性到定性与定量相结合;从单一到综合;从静态到动态。目前,资源环境承载力评价方法主要是以生态足迹法为主,今后,结合实际研究对象的特点,要充分运用数学、系统理论、动力学、计算机科学、计量经济学、环境学等理论,逐步建立完善的、动态的、准确的资源环境承载力评价方法和模型。%This paper researches the domestic and foreign relevant literature information about resources and environmental carryin g capacity between 1991 and 2012 based on content analysis method. And it takes 978 papers related to resources and environment carrying capacity which was sifted via searching the database of CNKI, SCI and SSCI as the subject investigated. Through comprehensive analysis of the model and evaluation method established and used by domestic and foreign literature information about resources and environmental carrying capacity, this paper introduces the characteristics and trends, these are: from qualitative to the integration of qualitative and quantitative, from single to comprehensive, from static to dynamic state. Now, ecological footprint approach dominates resources and environment carrying capacity evaluation method. In the future, we should make full use of the theory such as mathematics, systems theory, dynamics, computer science, econometrics, environmental sciences based on the trait of investigation, and gradually establish a perfect, dynamic, and accurate evaluation method and model of resource environmental bearing capacity.

  11. 分布式发电系统中储能单元的容量优化%Capacity optimization of energy storage units in distributed generation system

    Institute of Scientific and Technical Information of China (English)

    王西伟; 熊炜; 刘君; 韩士博; 袁旭峰

    2013-01-01

    为了解决分布式发电系统中储能单元的容量优化问题,利用超级电容器储能与蓄电池储能的互补特性,将二者综合考虑,以最小成本为优化目标函数,系统性能指标为约束条件,应用混沌蚁群算法,进行容量的组合优化设计.结果表明,该方法是有效的.%In order to solve the problems of optimum size of energy storage capacity for distributed generation system,combinatorial optimization of ultracapacitor and battery's capacity using chaos ant colony algorithm was studied.The object was to minimize the initial investment of the storage section, with performance indices as constrained. The result shows that this approach is valid.

  12. Evaluation of Water Resources Carrying Capacity Based on Index System with Parameter Projection Pursuit Model——A Case Study in Shijiazhuang%基于指标体系投影寻踪模型的水资源承载力评价——以石家庄为例

    Institute of Scientific and Technical Information of China (English)

    马峰; 王千; 蔺文静; 王贵玲

    2012-01-01

    石家庄市处于我国缺水严重的华北地区,水资源利用一直倍受人们的关注,水资源承载力评价可为今后的地区水资源利用及规划提供建议.文章采用了综合指标法,根据石家庄市水资源具体情况和指标体系结构特点,选取了18个指标建立水资源承载力评价指标体系及指标标准,运用投影寻踪方法建立评价模型,通过归一化处理、线性投影、构造投影指标函数和优化投影指标函数的方法,将选取的指标运用matlab数学软件进行投影寻踪分析,得到石家庄市水资源承载力等级水平为Ⅳ级,主要影响水资源承载力的指标为基本农田比例、节水灌溉率、灌溉用水有效利用系数、水资源可开发利用系数和万元工业增加值用水量等.%Shijiazhuang lies in the north of china which is seriously lack of water, and its water resources utilization always receives attention. The evaluation of water resources carrying capacity could provide advices for water resources utilization and planning in this area in future. Based on the specific conditions of water resources and the structural features of the index system in Shijiazhuang.18 indexes were selected to build the evaluation index system of water resources carrying capacity. The projection pursuit method was used to assess the model. Relying on the methods of normalization treatment, linear projection, constructing projection target function as well as optimizing projection target function, the selected indexes were analyzed using the projective pursuit method based on matlab platform. The results showed that the water resources carrying capacity level is grade IV in Shijiazhuang. The main indexes affecting the water resources carrying capacity included the basic farmland proportion, water-saving irrigation rate,effective utilization coefficient of irrigation water, utilization coefficient of available water resources, and water consumption of ten thousand yuan

  13. 分布式MIMO系统最优功率分配容量分析%Capacity Analysis of Optimal Power Allocation in Distributed MIMO Systems

    Institute of Scientific and Technical Information of China (English)

    王树坤; 高向川; 王忠勇; 路新华; 董素鸽

    2015-01-01

    大规模分布式MIMO( Distributed Multiple-Input Multiple-Output,D-MIMO)系统的性能不仅受到小尺度瑞利衰落的影响,而且还受到路径损耗的影响,系统的容量分析存在一定的困难。目前容量分析多以天线等功率分配为主。基于信道统计信息,结合线性排列天线的结构特点,针对大规模分布式MIMO功率优化后的容量性能进行分析,提出一种最优功率分配方案。与传统的等功率分配方案相比,最优功率分配方案可以使分布式MIMO系统的容量获得较大提升。%The performance of D-MIMO ( Massive Distribute Multiple-Input Multiple-Output) systems is affected not only by small-scale Rayleigh fading but also by path loss. There exist certain difficulties in an-alyzing the capacity of Massive D-MIMO systems. At present, plenty of system capacity analysis focuses on equal power allocation of each transmission antenna. Based on CSI (Channel Statistics Information), the structure of linear antennas, and the capacity analysis of the system with optimal power allocation, an optimal power allocation scheme is proposed. Comparison with the traditional equal power allocation indi-cates that the optimal power allocation scheme could evidently increase the capacity of D-MIMO system.

  14. Estimates of carrying capacity for sea otters in Washington state

    Science.gov (United States)

    Laidre, K.L.; Jameson, R.J.; Jeffries, S.J.; Hobbs, R.C.; Bowlby, C.E.; VanBlaricom, G.R.

    2002-01-01

    Analyses of eggs of three species of North American accipitrine hawks for organochlorines and heavy metals indicate that contamination with DDE may be the primary cause of recent population declines of two of the species, Cooper's hawk and sharp-shinned hawk.

  15. Langkawi Island, Social Aspect and the Carrying Capacity

    National Research Council Canada - National Science Library

    Mohamad, Diana; Jaafar, Mastura; Marzuki, Azizan

    2014-01-01

    The aptitude to convince a range of preferences has facilitated the island tourism attractions to achieve international recognition and at present KILIM Geopark is enjoyed by a prominent percentage...

  16. Wildlife carrying capacities in relation to human settlement

    OpenAIRE

    S.K. Eltringham

    1990-01-01

    Human encroachment into wildlife areas, which has increased almost exponentially over the past few decades, has usually resulted in the elimination of the larger species, particularly the large mammals. This is not an inevitable consequence and this paper considers the extent to which man and wildlife can coexist. There is a linear inverse relationship between human and elephant densities and the reasons for this are discussed with particular reference to Uganda. Such a relationship does not ...

  17. Load-carrying capacity assessment of composite (GRP) sandwich pipes

    OpenAIRE

    Hansen, Mathias

    2012-01-01

    Oppgaven tar for seg en rekke mekaniske egenskaper i en glassfiberarmert kompositt. En rekke eksperimenter har blitt utført og resultatene har blitt verifisert ved hjelp av en elementmetode-basert numerisk løser.

  18. The Pore Size Distribution of Naturally Porous Cigarette Paper and its Relation to Permeability and Diffusion Capacity

    Directory of Open Access Journals (Sweden)

    Eitzinger Bernhard

    2015-09-01

    Full Text Available La distribution de la taille des pores détermine la perméabilité d’air et la capacité de diffusion d’un papier à cigarettes, et par conséquent elle a une influence signifiante sur les échanges gazeux à travers le papier à cigarettes, non seulement d’une cigarette allumée, mais aussi d’une cigarette qui s’éteint. Pour le dessin des cigarettes, et notamment des papiers à cigarettes, il faut comprendre comment la distribution de la taille des pores du papier à cigarettes est influencée par la structure et les qualités du papier, ainsi que comment la distribution de la taille des pores influence la perméabilité d’air et la capacité de diffusion.

  19. Distribution of dissolved organic carbon and metal-binding capacity among ultrafilterable fractions isolated from selected surface waters of the southeastern United States

    Science.gov (United States)

    Alberts, James J.; Giesy, John P.; Evans, David W.

    1984-06-01

    The binding capacities of surface waters for Cd, Cu, and Pb were determined for eight water samples representing four rivers and two swamps from Florida and Georgia in the southeastern United States The binding capacity ranges were CdBC=0 04 to 0 79 μg atm/L, CuBC=1 0 to 5 4 μg atm/L, and PbBC=5 0 to 17 8 μg atm/L Binding capacity values from the southeastern United States are shown to be in good agreement with values reported from the northeastern part of the country and northern Europe The CdBC was due primarily to inorganic ligand binding, while PbBC was predominantly a result of organic matter The CuBC was due to a complex function of both organic and inorganic binding Significant portions of the CuBC and PbBC could be removed from the waters by ultrafiltration of particles between 0·45 μm and 52 Å in diameter Ultrafiltration, even to removing particles > 13 Å diameter, did not affect the CdBC Distributional studies of the dissolved organic carbon in these systems reveal that significant fractions of the DOC are present in the ultrafilterable fraction which contains significant portions of the CuBC and PbBC

  20. 全国资源环境承载能力监测预警(2014版)学术思路与总体技术流程%Academic Thought and Technical Progress of Monitoring and Early-warning of the National Resources and Environment Carrying Capacity (V 2014)

    Institute of Scientific and Technical Information of China (English)

    樊杰; 王亚飞; 汤青; 周侃

    2015-01-01

    It is an innovative work of comprehensive deepening reforms of China to establish the mechanism of monitoring and early-warning of carrying capacity. Based on the scientific connotation of the carrying capacity of national resources and environment and oriented to regional sustainable development, this article explores the“pressure-state-response”process of the interaction between the carrying body: the natural foundation (which consists of resources, environment, ecology and disasters) with the carrying object:the human produc-tion and life activities, and presents the academic thought that the early-warning of the national resources and environment carrying capacity is an overload early-warning according to the cap of the constraints of resources and environment or the population and economic rational scales or other key thresholds, and also presents a process early-warning in terms of the changes of the natural basic conditions or the tendencies of the impact of resource utilization and environmental changes. According to the exploration on the principles of early-warn-ing carrying capacity, this article constructs the differential indicator system and the overall technical process of early-warning of marine and terrestrial resources and environment carrying capacity. Land resources stress index, water resources use intensity index, environmental stress strength index and vegetation coverage change range index are chosen as basic indicators to conduct an overall regional evaluation, and different specific indi-cators, such as the pollution level of dust-haze, the increase and decrease of arable land, equilibrium index of grass and livestock and the variation of eco-environmental quality, are chosen to conduct the specific evalua-tion respectively for the urbanized areas, major grain producing areas, pastoral and semi-pastoral areas and eco-logical function areas, and then the key thresholds of these indicators are determined to conduct classifying evaluation

  1. 滇中典型流域水资源生态足迹与生态承载力研究%Study on the Water-resource Ecological Footprint & Ecological Carrying Capacity of the Typical Watersheds in the Middle of Yunnan Province

    Institute of Scientific and Technical Information of China (English)

    葛强; 雷艳娇

    2014-01-01

    After the analysis of the sustainable development of the water resources of Longchuanjiang River Water -shed , the computational method of the ecological footprint and carrying capacity to evaluate the different features under the different water use methods .The results showed that in considering the situation of the water diversion from outside watersheds, the water resources of Longchuanjiang River Watershed is surplus that improved the carrying capacity .The ecological carrying load of the water resources is larger than the ecological footprints , and the use method of water re-sources is at the comparatively sustainable manner.%在分析龙川江流域水资源可持续利用的状况下,运用生态足迹理论和计算方法,建立龙川江流域水资源生态足迹和生态承载力的计算模型,进行评估各用水方式下的水资源生态足迹和生态承载力特征。结果表明,在考虑外流域调水的情景下,龙川江流域水资源处于盈余状态,提高了水资源生态承载力;水资源生态承载力大于水资源生态足迹,水资源的利用方式处于相对可持续利用状态。

  2. Environmental factors shaping the abundance and distribution of laccase-encoding bacterial community with potential phenolic oxidase capacity during composting.

    Science.gov (United States)

    Lu, Lunhui; Zeng, Guangming; Fan, Changzheng; Guo, Jinsong; Zhang, Jiachao; Chen, Ming; Wu, Haipeng; Yuan, Yujie; He, Xiaoxiao; He, Yan

    2015-11-01

    Increasing molecular evidence points to a wide occurrence of laccase-like multicopper oxidase (LMCO)-encoding genes in bacteria. Most researches mainly focused on the bacterial LMCO diversity, whereas the processes and the environmental factors responsible for structuring bacterial LMCO communities remain relatively unknown in a composting system. Six gene libraries were constructed from samples in representative stages during composting. A total of 185 sequences obtained from sample DNA extracts were classified to 59 operational taxonomic units (OTUs) based on 10 % cutoff. The distribution profile of bacterial LMCO genes showed that proteobacterial- and actinobacterial-associated species were the dominant communities during composting. Pearson correlation analysis indicated that the pile temperature and water-soluble carbon (WSC) content were significantly positively correlated with bacterial LMCO gene OTU numbers, Chao1 and Shannon index, whereas the humic acid (HA)-like carbon content had the most significant effect on the distribution of the bacterial LMCO genes during composting by redundancy analysis. These findings will improve the understanding of the mutual relationship between environmental factors and bacterial LMCO community compositions in composting.

  3. Persistent Morbillivirus Infection Leads to Altered Cortactin Distribution in Histiocytic Sarcoma Cells with Decreased Cellular Migration Capacity

    Science.gov (United States)

    Pfankuche, Vanessa Maria; Sayed-Ahmed, Mohamed; Contioso, Vanessa Bono; Spitzbarth, Ingo; Rohn, Karl; Ulrich, Reiner; Deschl, Ulrich; Kalkuhl, Arno; Baumgärtner, Wolfgang; Puff, Christina

    2016-01-01

    Histiocytic sarcomas represent rare but fatal neoplasms in humans. Based on the absence of a commercially available human histiocytic sarcoma cell line the frequently affected dog displays a suitable translational model. Canine distemper virus, closely related to measles virus, is a highly promising candidate for oncolytic virotherapy. Therapeutic failures in patients are mostly associated with tumour invasion and metastasis often induced by misdirected cytoskeletal protein activities. Thus, the impact of persistent canine distemper virus infection on the cytoskeletal protein cortactin, which is frequently overexpressed in human cancers with poor prognosis, was investigated in vitro in a canine histiocytic sarcoma cell line (DH82). Though phagocytic activity, proliferation and apoptotic rate were unaltered, a significantly reduced migration activity compared to controls (6 hours and 1 day after seeding) accompanied by a decreased number of cortactin mRNA transcripts (1 day) was detected. Furthermore, persistently canine distemper virus infected DH82 cells showed a predominant diffuse intracytoplasmic cortactin distribution at 6 hours and 1 day compared to controls with a prominent membranous expression pattern (p ≤ 0.05). Summarized, persistent canine distemper virus infection induces reduced tumour cell migration associated with an altered intracellular cortactin distribution, indicating cytoskeletal changes as one of the major pathways of virus-associated inhibition of tumour spread. PMID:27911942

  4. Zinc distribution and speciation in Arabidopsis halleri x Arabidops is lyrata progenies presenting various zinc accumulation capacities

    Energy Technology Data Exchange (ETDEWEB)

    Sarret, Geraldine; Willems, Glenda; Isaure, Marie-Pierre; Marcus, Matthew A.; Fakra, Sirine C.; Frerot, Helene; Pairis, Sebastien; Geoffroy, Nicolas; Manceau, Alain; Saumitou-Laprade, Pierre

    2010-04-08

    - The purpose of this study was to investigate the relationship between the chemical form and localization of zinc (Zn) in plant leaves and their Zn accumulationcapacity. - An interspecific cross between Arabidopsis halleri sp. halleri and Arabidopsis lyrata sp. petrea segregating for Zn accumulation was used. Zinc (Zn) speciation and Zn distribution in the leaves of the parent plants and of selected F1 and F2 progenies were investigated by spectroscopic and microscopic techniques and chemical analyses. - A correlation was observed between the proportion of Zn being in octahedral coordination complexed to organic acids and free in solution (Zn?OAs + Znaq) and Zn content in the leaves. This pool varied between 40percent and 80percent of total leaf Zn depending on the plant studied. Elemental mapping of the leaves revealed different Zn partitioning between the veins and the leaf tissue. The vein : tissue fluorescence ratio was negatively correlated with Zn accumulation. - The higher proportion of Zn?OAs + Znaq and the depletion of the veins in the stronger accumulators are attributed to a higher xylem unloading and vacuolar sequestration in the leaf cells. Elemental distributions in the trichomes were also investigated, and results support the role of carboxyl and⁄ or hydroxyl groups as major Zn ligands in these cells.

  5. "Christian carrying goomies".

    Science.gov (United States)

    1994-01-01

    Dr. Passingan Usurup tells critics of his pragmatic approach on condom promotion that he is a Christian carrying condoms for Christ. He is head of the University of Papua New Guinea Medical Center and is credited with developing an AIDS/HIV policy for the Papua New Guinea Defence Force. The condoms were named Goomy and promoted at launching in 1992 in a blue packet under the slogan "The bond that guards." Goomy was chosen as the name because it is pidgin for rubber, chewing gum, and anything associated with rubber. Blue packets were chosen over the calls of most soldiers for a camouflage design because of its universal appeal as the color of the sea and sky and because it was the preference of women in the airlines. Once firmly ensconced in his role at the University, Usurup plans to develop a policy for students and staff and help to conduct AIDS prevention and education activities on campus. He will encourage students to test for HIV rather than highlighting the gloom and doom of infection and disease.

  6. Study on the Assessment of the Comprehensive Carrying Capacity in Core Grain-production Districts --Taking Shangqiu City, Henan Province as an Example%粮食生产核心区综合承载力评价研究——以河南省商丘市为例

    Institute of Scientific and Technical Information of China (English)

    杨建涛; 高建华; 王进学

    2012-01-01

    提高粮食生产核心区综合承载力是实施国家主体功能区战略、推进粮食生产核心区建设的重要价值取向。以综合承载力研究成果为基础,从我国粮食生产核心区城乡三次产业承载水平的角度,初步构建评价区域综合承载力的影响因子和模型,对商丘市2000-2009年城乡三次产业综合承载力实证研究的结果表明:当前农村呈现超载状态,城镇虽尚可载但水平不足,城乡综合承载力与现有人口规模基本持平,区域城镇化和城乡统筹发展有待提速。因此,粮食生产核心区应着力发展现代农业、大力提高城市综合承载力、不断拓展城市市区和功能新区发展空间。%To improve the Comprehensive Carrying Capacity (CCC) in Core Grain-production Districts (CGD) is an important goal for the implementation of Principal Functional Region strategy and the construction of CGD. Based on the researching progress analysis of CCC, this paper initially constructs CCC impact index and the CCC assessment model from the point of urban-rural industrial carrying capacity, and takes Shangqiu City as an example to empirically research its industrial carrying capacity in 2000 -2009. Studies show that the current status of rural CCC is overloading, the urban CCC is strong but can hold on less, the overall level of urban-rural CCC is as fiat as the existing population size. Then it points that regional urbanization and urban- rural coordinating development is to be accelerated. Therefore, to improve CCC, steps should be taken in CGD to pay close attention to modern agriculture, to enhance urban CCC vigorously, and to extend the development space of urban district and new functional districts.

  7. 武汉地区健康婴幼儿肺炎链球菌携带率及血清型分布%Study on the carrying rate and serotype distribution of streptococcus pneumoniae of healthy infants in Wuhan

    Institute of Scientific and Technical Information of China (English)

    赵德峰; 胡权; 熊燕; 全永霞; 艾运生; 王建坤

    2012-01-01

    OBJECTIVE To study the carrying rate and serotype distribution of nasopharyngeal streptococcus pneumonia of health infants in Wuhan. METHODS the Samples of rhinal and throat from 12-18 month-old healthy infants were collected, who came from 3 communities in Wuhan, at April and December in 2009. We used "Optoehin" experiment for strains identification and "Neufeld reaction" to test serotype. RESULTS 607 subjects were collected from the samples during the study. 75 strains of Streptococcus pneumoniae were isolated, and the rate of healthy infants carrying streptococcus pneumoniae in nasopharynx was 12.4%. The carrying rate of different seasons and sexes had no significant difference; Serotypes involved 13 types/groups, which mainly owned 19F (20.0%, 15/75), 19A (8.0%, 6/75), 6A (8.0%, 6/75), 6B (6.7%, 5/75), 15 (8.0%, 6/75), 23F (6.7%, 5/75), 14 (5.3%, 4/75), and distributed more widely in winter than in spring; 7 and 13-valent pneumococcal vaccine coverage was 38.7% and 54.7% in serum. CONCLUSION The carrying rate of Streptococcus pneumoniae at nasopharyngeal in 12-18 month-old healthy infants is less than that of the children over 2 year-old, and the 19F is the predominant serotype.%目的 了解武汉地区健康婴幼儿鼻咽部肺炎链球菌携带率及血清型分布.方法 选取武汉地区3个社区,于2009年4月和12月对12~18月龄健康婴幼儿进行鼻咽拭子采样,采用“Optochin”实验进行细菌鉴定,采用“Neufeld 反应”试验进行血清分型.结果 研究期间共采集596名研究对象鼻咽拭子样本,分离到肺炎链球菌75株,健康婴幼儿鼻咽部肺炎链球菌携带率为12.6%,季节、性别之间携带率差异无统计学意义;血清分型涉及13个型/群,主要分布在19F (20.0%、15/75)、19A (8.0%、6/75)、6A (8.0%、6/75)、15 (8.0%、6/75)、6B (6.7%、5/75)、23F (6.7%、5/75)、14 (5.3%、4/75),冬季比春季分布广;7价、13价肺炎疫苗的血清覆盖率为38.7%和54.7

  8. Optical information capacity of silicon

    CERN Document Server

    Dimitropoulos, Dimitris

    2014-01-01

    Modern computing and data storage systems increasingly rely on parallel architectures where processing and storage load is distributed within a cluster of nodes. The necessity for high-bandwidth data links has made optical communication a critical constituent of modern information systems and silicon the leading platform for creating the necessary optical components. While silicon is arguably the most extensively studied material in history, one of its most important attributes, an analysis of its capacity to carry optical information, has not been reported. The calculation of the information capacity of silicon is complicated by nonlinear losses, phenomena that emerge in optical nanowires as a result of the concentration of optical power in a small geometry. Nonlinear losses are absent in silica glass optical fiber and other common communication channels. While nonlinear loss in silicon is well known, noise and fluctuations that arise from it have never been considered. Here we report sources of fluctuations...

  9. Can Structural Adjustment and Carrying Capacity Promotion Promote the Tourism Economic Growth?-Case of the Three Coastal Economic Zones in Eastern China%结构调整、承载力提升能促进旅游经济增长吗?--以东部沿海三大经济区为例

    Institute of Scientific and Technical Information of China (English)

    刘佳; 周长晓

    2015-01-01

    With China’s Bohai coastal region,Yangtze river delta and Pan-pearl river delta coastal economic zone as the object of research,this paper evaluates and measures the three regions’tourism industry structure level and tourism ecological carrying index respectively from 2003 to 2012,and reveals the spatial difference of the coast-al three regions from the perspectives of structure and bearing capacity,then analyses and tests the effect of industri-al structure and bearing capacity on the tourism economic growth.The results show that three coastal regional tourism industrial structure transformed to rationality,the overall level of development is on the rise,but the Yangtze river delta and the Pearl river delta are instability,the fluctuation trend of tourism industry in Bohai Coastal region become smaller.The tourism ecology capacity of three regions has a slight increase,but tourism ecological demand is greater than the supply,it makes the three regions’tourism ecological in the deficit state,and the tourism ecological deficit is bigger and bigger,the promotion of tourism ecological carrying capacity and the tourism industry structure adjustment can effectively promote the tourism economic growth,but the positive effect of tourism industrial structure is greater than the tourist ecological carrying capacity.%以中国环渤海、长三角、泛珠三角三大沿海经济区为研究对象,分别对2003—2012年三大地区的旅游产业结构水平和旅游生态承载力指数进行测度和评价,并从结构和承载力视角,揭示沿海三大区域空间差异特征,进而分析和检验产业结构、承载力对旅游经济增长的作用。结果表明,2003—2012年中国沿海三大区域的旅游产业结构向合理化和高度化转化,总体发展水平呈上升趋势,但长三角、珠三角波动较大表现出不稳定性,环渤海地区旅游产业结构波动趋势逐渐变小。各地区旅游生态承载力略有提升

  10. Comprehensive Evaluation and Analysis on the Water Resources Carrying Capacity Levels in the Kaidu-Kongqi River Basin%开都河-孔雀河流域水资源承载力水平的综合评价与分析

    Institute of Scientific and Technical Information of China (English)

    王长建; 张小雷; 杜宏茹; 汪菲

    2012-01-01

    This is a case study in Kaidu River-Kongqi River basin of Xinjiang.Most of the data come from the 《Bulletin of Water Resources in Xinjiang Autonomous Region》(2000 and 2008),《Xinjiang Statistical Yearbook》(2001 and 2009),《Xinjiang Municipality,County Building Statistical Yearbook》(2000 and 2008),and a few data collected by the authors.The water resources carrying capacity evaluation index system was established by using the principle of entropy analysis,including quantitative analysis and empowered objective indicators.The index system in the water resources carrying capacity was used to determine the weight,and used to eliminate subjective factors.Then,the comprehensive score of the water resources carrying capacity in the study area was obtained.Comprehensive evaluation score of each county and Municipality indicates that water resources carrying capacity in the river basin presents not only a downward changing trend but also a significant spatial difference.Using factor analysis and multiple linear regression models,the power factor affecting the change in water resources carrying capacity is obtained.The unreasonable relationship between industrial structure and water use structure results in a strong braking effect.Slowing water-use efficiency improvement and reduction of investment in water conservancy facilities also affect further enhancing capacity level of water resources.In order to enhance the level of water resources capacity and realize sustainable development,some useful ideas are presented.The ideas include strengthening the construction of water sources and ecological protection zones,developing water-saving agriculture and efficient water irrigation techniques,and optimizing the industrial structure and water utilization structure.It is necessary to improve water use efficiency,to improve watershed management regulations and laws,to strengthen supervision and law enforcement,in order to build a unified management model

  11. Visual attention capacity

    DEFF Research Database (Denmark)

    Habekost, Thomas; Starrfelt, Randi

    2009-01-01

    to patient testing, and review existing TVA-based patient studies organized by lesion anatomy. Lesions in three anatomical regions affect visual capacity: The parietal lobes, frontal cortex and basal ganglia, and extrastriate cortex. Visual capacity thus depends on large, bilaterally distributed anatomical...

  12. The Ecological Carrying Capacity for Education System of Overseas Students ——A Case Study of Yunnan Province%来华留学生教育系统生态承载力分析——基于云南省的实证

    Institute of Scientific and Technical Information of China (English)

    段从宇

    2012-01-01

    Yunnan foreign students in education system in.provincial capital cities on the distribution of resourcesand regional central city of polarization trend. Environmental bearing capacity of political system, but the higher leveleconomic capacity and cultural environment capacity, especially with "obvious" as the core of scholarship at internal economic environment capacity and to "foreign teachers~ as the core of the internal cultural environment capacity overall low threshold range in a certain extent, hampered the general education in Yunnan foreign students. Students have less and recruit professional focus on professional recruitment, ecological system is elastic strength and flexibility of ecologicalweak overall degrees%生态承载力是衡量云南来华留学生教育系统的自我维持、自我调节和应对外部环境变化的重要依据。基于"资源承载力"、"环境承载力"和"生态弹性力"三个维度的分析表明,云南来华留学生教育系统在资源分布上呈"省会城市"和"地级中心城市"的两极分布;系统政治环境承载力保持较高水平,但经济承载力和文化环境承载力明显不足,尤其是以"奖学金受众面"为核心的内部经济环境承载力和以"外籍教师数量"为核心的内部文化环境承载力总体处于较低阀值;在系统生态弹性力方面,来华留学生招生的师资供容能力不足和专业设置趋同,导致系统生态弹性强度和生态弹性性度总体偏弱。

  13. 龙滩水库八达村库湾水质变化及网箱养鱼容纳量%Effect of Water Qual ity Change on Carrying Capacity in Net Cage Aquaculture along Bada Village Bay of Longtan Reservoir in Guizhou

    Institute of Scientific and Technical Information of China (English)

    谢巧雄; 姚俊杰; 周路; 莫仁义; 张健; 罗永成; 崔巍

    2014-01-01

    为充分利用龙滩水库的水域,使水面既发挥其养殖功能,又最大限度地保护水体的其他功能,采取化学分析法与物料平衡法联用的估算方法,以养殖过程中物质输入输出的平衡方程间接推算水域环境对投饵网箱养殖容量的限制程度。结果表明:龙滩水库罗甸县茂井镇八达村库湾水体溶解氧、总磷、透明度指标基本处于贫中营养与中营养水环境标准之间,化学需氧量、总氮则达到富营养水环境标准。若全部采用A网箱、B网箱、C网箱模式,龙滩水库罗甸县茂井镇八达村库湾水域的鱼类负载量分别为230.3~276.5 t、364.4~437.4 t和944.4~1133.8 t,C网箱、B网箱的养殖容量分别是A网箱模式的4.1倍和1.6倍,表明不同的网箱养殖模式直接影响水产养殖容纳量的变化。%The effect of water quality on carrying capacity in net cage aquaculture was studied by estimation methods of chemical analysis and material balance to develop and protect the aquaculture function and other water function of Longtan reservoir.The results showed that the indexes of dissolved oxygen,total P and transparency were between poor-middle nutrition and middle nutrition environment standard and the indexes of chemical oxygen demand and total N reached the eutrophic water environment standard.The fish capacity of net cage A,B and C aquaculture patterns can be 230.3~276.5 t,364.4~437.4 t and 944.4~1 133.8 t respectively,which indicates that net cage aquaculture pattern has the direct effect on carrying capacity in aquaculture production.

  14. Station Capacity

    DEFF Research Database (Denmark)

    Landex, Alex

    2011-01-01

    Stations are often limiting the capacity of railway networks. This is due to extra need of tracks when trains stand still, trains turning around, and conflicting train routes. Although stations are often the capacity bottlenecks, most capacity analysis methods focus on open line capacity. Therefore......, this paper presents methods to analyze station capacity. Four methods to analyze station capacity are developed. The first method is an adapted UIC 406 capacity method that can be used to analyze switch zones and platform tracks at stations that are not too complex. The second method examines the need...... the probability of conflicts and the minimum headway times into account. The last method analyzes how optimal platform tracks are used by examining the arrival and departure pattern of the trains. The developed methods can either be used separately to analyze specific characteristics of the capacity of a station...

  15. Comparación de métodos basados en los requerimientos nutricionales y disponibilidad de biomasa para estimar la capacidad de carga para venado cola blanca Comparison of methods based on the nutritional requirements and availability of biomass to estimate carrying capacity for white tailed deer

    Directory of Open Access Journals (Sweden)

    FX Plata

    2011-01-01

    Full Text Available Debido a la importancia que tiene la metodología en la estimación de la capacidad de carga (K animales/ha en venado cola blanca, los objetivos de este trabajo fueron: 1 Comparar la estimación de la K por cinco métodos; tres basados en disponibilidad de compuestos nutritivos (materia seca (MS, energía digestible (ED y nitrógeno (N, otro basado en la presión de pastoreo y un último en el requerimiento de energía metabolizable (EM estimado con base al metabolismo ecológico del venado, y 2 Comparar la K estimada al usar la biomasa total o por los grupos de vegetales consumidos por el venado (gramíneas, herbáceas, arbustivas y arbóreas. Se utilizó la información de composición de la dieta y de biomasa de un rancho cinegético localizado en Aguascalientes, México. Los resultados fueron analizados de acuerdo a un modelo con arreglo factorial (5 x 5, donde los factores fueron el método de estimación y el grupo vegetal. Los valores de K estimados con biomasa total fueron los mayores (1,449, seguidos por los pastos (0,707, luego por las herbáceas (0,325, mientras que los estimados con arbóreas y arbustivas dieron los menores valores (0,228 y 0,03. La estimación de K por medio de plantas arbustivas (0,033 venados/ha proporciona un valor más similar al de la densidad poblacional (0,02-0,04 venados/ha que el estimado con otros grupos vegetativos, independientemente del método seleccionado (disponibilidad de MS, ED, N, metabolismo ecológico y la presión de pastoreo. Considerando la densidad poblacional (0,02-0,04 venados/ha como el indicador apropiado para evaluar la capacidad de carga, se concluye que debe estimarse con base a la disponibilidad de arbustivas.Due to the importance of the estimation of carrying capacity (K animals/ha in white tailed deer, the objectives of this study were: 1 To compare the estimation of K with five methods, three of them based on nutrient availability (dry matter (DM, digestible energy (DE and

  16. 峰谷电价下配电网中分布式储能的容量配置%Capacity Configuration of Distribution Energy Storage in Distribution Network Under the Peak-valley Price

    Institute of Scientific and Technical Information of China (English)

    杨江涛; 孙春顺; 杨安; 刘佳

    2016-01-01

    为了进一步提高电力系统的可靠性和经济性,对配电网中储能设备的容量进行合理配置。基于分布式储能装置的引入给配电系统带来的影响,并考虑峰谷电价政策的影响,针对储能装置带来的经济效益分别从发电侧、输配电过程、降低网损、峰谷电价效益等各方面进行了经济性上的量化;结合储能装置的自身成本,以年收益最大为目标建立了储能装置容量的优化配置模型。最后考虑储能装置给系统潮流带来的影响,在约束条件中加入节点电压波动约束,通过对算例进行分析,得到了不同类型储能设备的最优容量配置。%In order to improve the reliability and economy of power system further, the capacity of energy storage device should be allocated with ration in the power distribution network. This paper analyzes the effect of the energy storage device on the power distribution system. On this basis, taking the influence of the peak valley price policy on the system into consideration, the benefits of the energy storage device to the system are analyzed, from the as-pects of the power generation, transmission and distribution process, network loss reduce, peak valley price benefit and so on, and are quantified on the side of economy. Combined with the costs of the energy storage device, with the goal of maximizing the revenue, an optimal allocation model of energy storage device capacity is established. Finally, considering the effects of energy storage device to the system trend and adding node voltage fluctuation in constraint conditions, the optimal capacity configurations of different types of energy storage devices are obtained by the analysis of the proposed example.

  17. Station Capacity

    DEFF Research Database (Denmark)

    Landex, Alex

    2011-01-01

    Stations are often limiting the capacity of railway networks. This is due to extra need of tracks when trains stand still, trains turning around, and conflicting train routes. Although stations are often the capacity bottlenecks, most capacity analysis methods focus on open line capacity. Therefore......, this paper presents methods to analyze station capacity. Four methods to analyze station capacity are developed. The first method is an adapted UIC 406 capacity method that can be used to analyze switch zones and platform tracks at stations that are not too complex. The second method examines the need...... for platform tracks and the probability that arriving trains will not get a platform track immediately at arrival. The third method is a scalable method that analyzes the conflicts in the switch zone(s). In its simplest stage, the method just analyzes the track layout while the more advanced stages also take...

  18. 高强薄壁冷弯卷边槽钢柱承载力计算方法%Calculation method for load-carrying capacity of high strength thin-wall cold-formed lipped channel columns under axial compression

    Institute of Scientific and Technical Information of China (English)

    金梦飞; 刘昕露; 吕呈; 孙德发

    2014-01-01

    Based on the contrast analysis of the Effective Width Method and the Direct Strength Method, analysis and discussion are mentioned about the ultimate load-carrying capacities of 1 mm thickness Q345 cold-formed thin-wall steel lipped channel columns. The calculation and test results showed that, it is relative safety in calculation the lipped channel columns according to GB 50018-2002 Technical Code of Cold-Formed Thin-wall Steel Structure.%在分析比较有效宽度法( EWM)和直接强度法( DSM)的基础上,以1 mm厚Q345冷弯薄壁卷边槽钢柱为例,对其极限承载力进行了较深入的探讨和对比分析,计算与试验结果表明:按GB 50018-2002冷弯薄壁型钢结构技术规范计算槽钢柱是可行的。

  19. 分层损伤和完好复合材料薄壁加筋板的后屈曲承载能力及破坏形式%Post-bucking Carrying Capacity and Failure Modes of Composite Thin-wall Stiffened Panels with and without Damage

    Institute of Scientific and Technical Information of China (English)

    谢紫龙; 尚柏林; 常飞; 杨哲; 尹俊杰

    2013-01-01

    Delamination damage was prefabricated on composite thin-wall stiffened panels used in advanced aircraft by impact test,and then the buckling,post-buckling carrying capacity and failure modes of the samples with and without damage at shear load were studied by shear tests.The result show that the delamination damage could reduce the stiffness of the composite thin-wall stiffned panel and change its failure mode,and cause the obvious local buckling appearing during shear process,and thus greatly reduced bucking,post-bucking and damage loads.%利用冲击试验对先进飞机上常用的复合材料薄壁加筋板预制分层损伤,通过剪切试验研究了完好试样和损伤试样在剪切载荷下的屈曲、后屈曲承载能力及破坏形式.结果表明:分层损伤会降低复合材料薄壁加筋板的刚度,并改变其破坏形式,使其在剪切过程中出现明显的局部屈曲,进而大大降低其屈曲失稳载荷、后屈曲承载载荷和破坏载荷.

  20. On fast carry select adders

    Science.gov (United States)

    Shamanna, M.; Whitaker, S.

    1992-01-01

    This paper presents an architecture for a high-speed carry select adder with very long bit lengths utilizing a conflict-free bypass scheme. The proposed scheme has almost half the number of transistors and is faster than a conventional carry select adder. A comparative study is also made between the proposed adder and a Manchester carry chain adder which shows that the proposed scheme has the same transistor count, without suffering any performance degradation, compared to the Manchester carry chain adder.

  1. On fast carry select adders

    Science.gov (United States)

    Shamanna, M.; Whitaker, S.

    This paper presents an architecture for a high-speed carry select adder with very long bit lengths utilizing a conflict-free bypass scheme. The proposed scheme has almost half the number of transistors and is faster than a conventional carry select adder. A comparative study is also made between the proposed adder and a Manchester carry chain adder which shows that the proposed scheme has the same transistor count, without suffering any performance degradation, compared to the Manchester carry chain adder.

  2. Theoretical and experimental investigations on the cooling capacity distributions at the stages in the thermally-coupled two-stage Stirling-type pulse tube cryocooler without external precooling

    Science.gov (United States)

    Tan, Jun; Dang, Haizheng

    2017-03-01

    The two-stage Stirling-type pulse tube cryocooler (SPTC) has advantages in simultaneously providing the cooling powers at two different temperatures, and the capacity in distributing these cooling capacities between the stages is significant to its practical applications. In this paper, a theoretical model of the thermally-coupled two-stage SPTC without external precooling is established based on the electric circuit analogy with considering real gas effects, and the simulations of both the cooling performances and PV power distribution between stages are conducted. The results indicate that the PV power is inversely proportional to the acoustic impedance of each stage, and the cooling capacity distribution is determined by the cold finger cooling efficiency and the PV power into each stage together. The design methods of the cold fingers to achieve both the desired PV power and the cooling capacity distribution between the stages are summarized. The two-stage SPTC is developed and tested based on the above theoretical investigations, and the experimental results show that it can simultaneously achieve 0.69 W at 30 K and 3.1 W at 85 K with an electric input power of 330 W and a reject temperature of 300 K. The consistency between the simulated and the experimental results is observed and the theoretical investigations are experimentally verified.

  3. 艾司洛尔与急性心肌梗死患者红细胞携氧能力的关系研究%Study on the Relationship Between Esmolol and Erythrocyte Oxygen Carrying Capacity in Pa-tients with Acute Myocardial Infarction

    Institute of Scientific and Technical Information of China (English)

    孙向华; 韩莲花; 李红霞; 惠杰

    2014-01-01

    【目的】探讨艾司洛尔是否影响急性心肌梗死患者红细胞血红蛋白的携氧能力。【方法】采集急性心肌梗死患者红细胞,悬浮于不同pH值(pH7.4、pH5.0)等渗PBS缓冲液,分别用肾上腺素、艾司洛尔、艾司洛尔+肾上腺素预处理红细胞,在拉曼光谱点扫描检测单个活态红细胞内血红蛋白特征光谱变化。【结果】在pH5.0时,氧化血红蛋白特征峰峰强在PBS、艾司洛尔的作用下明显降低;在肾上腺素的作用下显著升高(P<0.05);而经艾司洛尔+肾上腺索预处理后,肾上腺素的这一作用不明显。【结论】艾司洛尔能减轻肾上腺素在酸性环境中增加红细胞血红蛋白的氧合力的作用,增加氧从血红蛋白的解离,有利于缺氧组织的供氧。%[Obj ective]To explore whether esmolol affects erythrocyte oxygen carrying capacity in patients with acute myocardial infarction.[Methods]Erythrocytes from patients with acute myocardial infarction were collected and suspended in isotonic PBS buffer solution with different pH value(pH7.4 and pH5.0).Erythro-cytes were pretreated with adrenaline,esmolol and adrenaline plus esmolol,respectively.The characteristic spectral changes of hemoglobin in single living erythrocytes were detected by using Raman spectroscopy analy-sis.[Results]Characteristic peak of oxyhemoglobin treated with PBS and esmolol at pH5.0 was decreased obvi-ously,but that treated with adrenaline was increased significantly. After pretreatment with esmolol plus adrenaline,the effect of adrenaline was not obvious.[Conclusion]Esmolol can reduce the effect of adrenaline for enhancing erythrocyte oxygen carrying capacity of hemoglobin in acid environment,and increase the disso-ciation of oxygen from hemoglobin,and is helpful for oxygen supply of anoxia tissue.

  4. Comparison of Oxygen Carrying Capacity of Red Blood Cell in Salvaged Blood of Patients Undergoing Orthopedic Surgery vs Peripheral Blood Before Anesthesia%骨科手术中回收血红细胞与患者麻醉前红细胞携氧能力的比较

    Institute of Scientific and Technical Information of China (English)

    邱颐; 丁玉美; 崔永武; 安敏

    2011-01-01

    [Objective]To compare the difference of oxygen carrying capacity of red blood cell between salvaged blood of patients undergoing orthopedic surgery and peripheral blood before anesthesia. [Methods] Thirty patients undergoing orthopedic surgery received autologous blood transfusion by using blood salvage machine during operation. Thirty blood samples in each of salvaged blood processed by blood salvage machine and peripheral blood before anesthesia were drawn.The pH of blood samples in two groups was measured. The formula was used to calculate 50 % partial pressure of oxygen (P50) in blood samples. The level of 2,3-diphosphoglycerate(2,3- DPG) in erythrocytes was measured by radioimmunoas say and red cell deformability index(RCD) was determined on blood rheology instrument. [Results] The pH and P50 in salvaged blood were higher than those in peripheral blood before anesthesia, but there was no significant difference( P > 0.05). There was also no significant difference in 2,3 DPG level and RCD between salvaged blood and peripheral blood before anesthesia( P >0.05). [Conclusion] The oxygen carrying capacity of red blood cell in salvaged blood of patients undergoing orthopedic surgery is the same as that in peripheral blood before anesthesia.%[目的]比较骨科患者术中回收血红细胞与麻醉前红细胞携氧能力的差异.[方法]使用血液回收机对30例骨科手术患者行术中自体血液回收.取血液回收机处理后的回收血和麻醉前患者外周血各30份,检测两组血样的pH、根据公式计算血样的50%氧分压(P50),采用放射免疫法测定红细胞内2,3-二磷酸甘油酸浓度(2,3-DPG)、在血液流变仪上测定红细胞变形指数(RCD).[结果]回收血样pH值、P50高于麻醉前血样,但无显著性差异(P>0.05);2,3-DPG 浓度、RCD与麻醉前血样比较差异亦无显著性(P>0.05).[结论]骨科患者术中回收血红细胞与麻醉前外周血红细胞具有相同的携氧能力.

  5. An Analysis of English Carrie

    Institute of Scientific and Technical Information of China (English)

    孙淑珍

    2004-01-01

    @@ Chapter Ⅰ Introduction Sitting in the rocking chair,Carrie dreams her future.This is the deep impression the novel"Sister Carrie"gives us,which is written by Theodore Dreiser(1871-1945),the great American realism writer.

  6. The water resources carrying capacity evaluation of Pulandian city during“The national twelfth five-year plan”construction period%普兰店市“十二五”建设期间水资源承载力评价

    Institute of Scientific and Technical Information of China (English)

    洪思扬; 刘欣

    2012-01-01

      In order to full exploit and utilize water resources, optimize the allocation of water resources in Pulandian City, to ensure sustained and stable economic and social development, we conduct the analysis and evaluation of present situation of water resources in Pulandian city and the carrying capacity of water resources during “The national twelfth five-year plan” period in Pulandian City. The results reflect an increasingly prominent con-tradiction between supply and demand. According to the actual condition of Pulandian city and the speed of economic develop-ment, we should try to exploit the existing potential of water conservancy, broaden sources of water resources and reduce expenditure simultaneously, draw up water resources planning with the principle of full consideration of urban and rural life, produc-tion, ecological water usage, to solve the contradiction of water resources supply and demand in urban and rural areas.%  为了更好的开发和利用水资源、优化水资源配置,确保普兰店市经济社会持续稳定的发展,我们对普兰店市水资源现状及“十二五”期间水资源承载能力进行了分析评价,评价结果反映出普兰店市水资源日益突出的供需矛盾。根据普兰店市的实际情况与经济发展速度,应尽量挖掘现有水源工程的潜力,开源节流并举,以充分考虑城乡生活、生产、生态用水的原则下,进行水资源配置规划,以解决城乡水资源供需矛盾。

  7. Distribution transformer capacity optimization and allocation based on optimum allocated load rate%基于最佳配置负载率的配电变压器容量优化与配置

    Institute of Scientific and Technical Information of China (English)

    殷德聪; 许跃进; 吴昊; 杨建

    2012-01-01

    It is very important to select distribution transformer capacity for power grid. It can optimize the allocation of transformer capacity and enhance the economical efficiency of distribution power grid. Using the idea of economic current density during the choice of wire, a new approach was proposed based on optimum allocated load rate to select distribution transformer capacity. First, a model of transformer capacity optimum allocation was established by using the new method, it not only contained investment, operation and maintenance fees and lost expenses, but also included the economic losses caused by transformer outage. Then, each cost model was constructed scientifically. All these were to achieve the target of minimum annual integrated cost. After optimization and calculation, recommended values of optimum allocated load rate for selecting one, two and three distribution transformers were obtained. Using the recommended values to select distribution transformer capacity is simple and feasible, economical and reasonable. Also, a technical support is provided for selecting distribution transformer capacity in power grid construction.%为实现配电变压器容量的最佳配置以及配电网的经济运行,配电变压器的容量选择研究具有重要意义.该文借鉴选择导线时经济电流密度的思想,提出了基于最佳配置负载率的配电变压器容量优化配置方法.利用该方法对变压器容量的优化配置进行建模,并以年综合费用最小为目标,模型中不仅考虑投资、运行维护费和损耗费用,还计入了变压器停运造成的经济损失.经优化计算,得出选择1台、2台及3台配电变压器时的最佳配置负载率推荐值.利用此推荐值选择配电变压器容量简便可行、可为电网建设中配电变压器容量的选择提供技术支持.

  8. Naturalistic Elements in Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    刘艳晖

    2007-01-01

    @@ Theodore Dreiser is considered to be a controversial writer.His first novel.Sister Carrie makes a new way of presenting re-ality.This paper discusses the naturalistic elements from the de-tailed description of the environment in that society.

  9. Coordination Capacity

    CERN Document Server

    Cuff, Paul; Cover, Thomas

    2009-01-01

    We develop elements of a theory of cooperation and coordination in networks. Rather than considering a communication network as a means of distributing information, or of reconstructing random processes at remote nodes, we ask what dependence can be established among the nodes given the communication constraints. Specifically, in a network with communication rates between the nodes, we ask what is the set of all achievable joint distributions p(x1, ..., xm) of actions at the nodes on the network. Several networks are solved, including arbitrarily large cascade networks. Distributed cooperation can be the solution to many problems such as distributed games, distributed control, and establishing mutual information bounds on the influence of one part of a physical system on another.

  10. DISTORTIONAL BUCKLING TEST AND CALCULATION METHOD OF LOAD-CARRYING CAPACITY OF COLD-FORMED THIN-WALLED STEEL LIPPED CHANNEL COLUMNS WITH CIRCLE HOLES IN WEB UNDER AXIAL COMPRESSION%腹板开圆孔冷弯卷边槽钢轴压构件畸变屈曲承载力试验及计算方法

    Institute of Scientific and Technical Information of China (English)

    姚行友; 郭彦利

    2016-01-01

    对26根屈服强度为235 MPa的腹板开孔和未开孔冷弯薄壁型钢截面轴压构件进行畸变屈曲承载力试验研究,分析构件的屈曲模式和极限承载力.将我国及北美相关规范计算的构件承载力以及非线性有限元数值模拟结果与试验结果进行分析比较,并对腹板开孔冷弯薄壁型钢截面轴压构件的承载力合理计算模式进行研究.结果表明:对于中等长度腹板开孔冷弯薄壁型钢截面轴压构件主要出现局部、畸变和整体屈曲的相关作用;腹板开孔对构件畸变屈曲稳定承载力有一定的降低作用;采用折减构件有效截面面积的修正方法可计算开孔构件的畸变屈曲稳定承载力;非线性有限元方法可用于腹板开孔冷弯薄壁型钢构件的屈曲模式和极限承载力的分析.%In order to research the distortional buckling mode and load-carrying capacity of cold-formed thin-walled steel members with holes, compression tests were conducted on 26 intermediate length columns with and without web holes.For each specimen, a shell finite element eigenbuckling analysis and nonlinear analysis were also conducted such that the influence of the hole on local, distortional, and global elastic buckling responses could also be got.The comparison of ultimate strength between test results and calculated results using relevant codes was made.The calculated method for cold-formed thin-walled steel columns with web holes was proposed.The results showed that the interaction of local buckling, distortional buckling, and overall buckling usually would occur in the intermediate length member under axial compression, and the web holes had a little influence on the elastic buckling strength and the distortional buckling ultimate strength of columns, the ultimate strength of the members with holes in web could be predicted using a reduced effective area, and the nonlinear finite element method could be used to analyse the buckling mode and

  11. Analysis on Grid-Connectible Capacity of Distributed PV Generation in Case of PV Generation Distribution Close to Load Distribution%分布式光伏电源与负荷分布接近条件下的可接入容量分析

    Institute of Scientific and Technical Information of China (English)

    刘健; 黄炜

    2015-01-01

    为了给分布式光伏电源接入规划提供科学决策依据,建立了负荷和分布式光伏电源在各种分布下所引起的电压偏差和电压波动数学模型。在此基础上,以分布式光伏电源引起的最大电压上偏差和最大电压波动以及无分布式光伏电源时单纯由负载引起的最大电压下偏差为约束条件,推导出了6种负荷和分布式光伏电源容量沿馈线相同分布条件下能够满足电压质量要求的分布式光伏电源允许接入容量范围。以城市配电网和农村配电网的典型参数为例对所提出方法进行了分析和说明,结果表明所建议方法是可行的,并且能够有效得出允许接入的分布式光伏电源的容量范围。%To offer reasonable foundation for the planning of grid-connection of distributed photovoltaic (PV) generations, the mathematical models for voltage deviation and voltage fluctuation caused by various distributions of loads and PV generations are established. Taking the maximum upper deviation of voltage and the maximum voltage fluctuation caused by distributed PV generations and the maximum lower voltage deviation caused by the load only when the PV generation does not exist as constraints, the capacity range of allowed grid-connected distributed PV generations, by which the demand on voltage quality can be met under six distribution conditions of load and distributed PV generations along the feeder, is derived. Taking typical parameters of urban distribution network and those of rural distribution network for example, the proposed method is analyzed and illustrated, results of the analysis show that the proposed method is feasible, and using the proposed method the allowed grid-connected capacity range of distributed PV generations can be determined.

  12. “抬类词”共时分布的历时考察%A Diachronic Study of the Synchronic Distribution of Chinese Words Indicating "to Carry by Two or More Persons"

    Institute of Scientific and Technical Information of China (English)

    殷晓杰; 宋小磊

    2012-01-01

    The meaning of "carrying by two or more persons" is expressed by tai (抬) in standard Chi- nese today, and by gang (扛) or yu (舁) in some dialects, but in ancient times there were competitions among the words collocated with these three characters. From the Eastern Han dynasty (25 -220) on, yu (舁) had been an indispensable character in forming words, until it was replaced by tai (抬) in the Ming dynasty (1368 -1644). The character Gang (扛),arising at more or less the same time as yu (舁), was probably a character restricted to south Chinese dialects in the history, having been in use in the north from the Yuan dy- nasty( 1206 -1368) on but eliminated from north Chinese dialects shortly after the Qing dynasty( 1644 -1911 ). As to tai (抬), it was first seen in the Tang dynasty(618 -907) and gradually became a kernel character after the Ming dynasty; it originated most probably from the official speech prevalent in the area where the Huaihe River pours into the Changjiang River, and later spread northward and southward to be more widely used.%表示“两人或两人以上合力举物”义,现代普通话用“抬”,方言中还有“扛”和“舁”,历史上这些词之间存在着竞争替换关系。从东汉起“舁”一直是通语中的主导词,直到明代被“抬”所取代;与“舁”基本同期出现的“扛”,历史上很可能是一个南方方言词,元以来也曾北上过,只是清以后逐渐从北方撤出;“抬”始见于唐代,明代以后逐渐成为新的通语主导词,“抬”很可能起源于江淮官话,然后往北往南扩散。

  13. Properties of Carry Value Transformation

    Directory of Open Access Journals (Sweden)

    Suryakanta Pal

    2012-01-01

    Full Text Available Carry Value Transformation (CVT is a model of discrete deterministic dynamical system. In the present study, it has been proved that (1 the sum of any two nonnegative integers is the same as the sum of their CVT and XOR values. (2 the number of iterations leading to either CVT=0 or XOR=0 does not exceed the maximum of the lengths of the two addenda expressed as binary strings. A similar process of addition of modified Carry Value Transformation (MCVT and XOR requires a maximum of two iterations for MCVT to be zero. (3 an equivalence relation is shown to exist on Z×Z which divides the CV table into disjoint equivalence classes.

  14. Integrated Assessment and Obstacle Factors of Environmental Carrying Capacity of National Strategic Economic Zones Based on Entropy and Catastrophe Progression Methods:A Case Study in Changchun-Jilin-Tumenjiang Development and Opening-up Pilot Area%基于熵值-突变级数法的国家战略经济区环境承载力综合评价及障碍因子——以长吉图开发开放先导区为例

    Institute of Scientific and Technical Information of China (English)

    赵宏波; 马延吉; 苗长虹

    2015-01-01

    The environmental carrying capacity is a parameter to measure the capacity degree between human being social activities and the environment. To study the theories and quantification, methods of environmental carrying capacity is of significance in reality for directing human beings economic behaviors and harmonizing the relationships between social development and environment. With the rapid development of social economy and population growth sharply in National Strategic Economic Zones, the resource consumption and pollutant emission are increasing accordingly, which made resources and environment system under tremendous pres-sure, this situation would impact the level of environmental carrying capacity of National Strategic Economic Zones. According to the catastrophic characteristics of environmental carrying capacity of National Strategic Economic Zones, we selected Changchun-Jilin-Tumenjiang development and opening-up Pilot Area as the re-search object. Based on the entropy and catastrophe progression methods, we built an index system to evaluate the environmental carrying capacity, in which Nature-Economy-Society (N-E-S) indexes are included. Using obstacle degree models, we analyzed the temporal pattern of environmental carrying capacity and the obstacle factors from 2000 to 2011.Results are shown as follows:1) Temporally, the level of environmental carrying ca-pacity rose from weak to moderate level from 2000 to 2011. 2) The proportion of environmental protection in-vestment in GDP, industrial waste water emissions, cultivated land fertilizer usage, the per Capita GDP, the en-ergy consumptions per GDP and economic density are the main obstacle factors affecting the environmental carrying capacity. The approach established in the article has a lot advantages when dealing with municipal projects under complex evaluation problems and it does not use any weight, only need to arrange indicators in an order of important degree according to the inherent logic

  15. 24 CFR 574.410 - Capacity.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Capacity. 574.410 Section 574.410... Project Sponsors § 574.410 Capacity. The grantee shall ensure that any project sponsor with which the grantee contracts to carry out an activity under this part has the capacity and capability to...

  16. Capacity and Capacity Utilization in Fishing Industries

    OpenAIRE

    Kirkley, James E; Squires, Dale

    1999-01-01

    Excess capacity of fishing fleets is one of the most pressing problems facing the world's fisheries and the sustainable harvesting of resource stocks. Considerable confusion persists over the definition and measurement of capacity and capacity utilization in fishing. Fishing capacity and capacity utilization, rather than capital (or effort) utilization, provide the appropriate framework. This paper provides both technological-economic and economic definitions of capacity and excess capacity i...

  17. A case study on non-point source pollution and environmental carrying capacity of animal raising industry in subtropical watershed%亚热带流域氮磷排放与养殖业环境承载力实例研究

    Institute of Scientific and Technical Information of China (English)

    孟岑; 李裕元; 许晓光; 高茹; 王毅; 张满意; 吴金水

    2013-01-01

    畜禽养殖业粪便排放已经成为我国农村地区主要的农业面源污染源之一,也是制约养殖业良性发展的主要瓶颈.本文以湖南省长沙县典型亚热带流域为研究单元,基于流域水环境定位观测、耕地氮(N)磷(P)消纳能力以及养殖业调查和土壤分析资料,初步分析了亚热带丘陵区的面源污染现状及畜禽养殖业的环境承载力.结果表明,研究区金井河流域134.4 km2范围内N、P年负荷分别为N 2.72 t·km-2和P0.11t·km-2,其中养殖粪便对水体总氮(TN)、总磷(TP)负荷的贡献率分别约为42.2%和62.0%.区内平均畜禽养殖密度为3.46 AU·hm-2(相当于流域内年出栏生猪24.39万头),显著高于现有化肥用量条件下流域的实际承载力1.13 AU·hm-2(相当于流域内年出栏生猪6.35万头),因此养殖密度过高是导致研究区水体NP负荷较高的主要原因.区内N、P盈余量分别为N 35.8 kg·hm-2、P 18.61 kg·hm-2.研究区基本不施用化肥条件下畜禽养殖业的最大环境承载力为7.26 AU·hm-2,在有机肥占合理施肥量30%条件下,当地畜禽养殖业的环境承载力为2.74AU·hm-2(相当于流域内年出栏生猪19.50万头).降低养殖密度、调整养殖业空间布局以及提高养殖废弃物的资源化利用率是防治当前面源污染的有效途径.%The discharge of faeces from animal production is a major source of nitrogen ( N) and phosphorus (P) pollutants in the subtropical region of China. To quantify the N and F load from animal production to hydro-systems in the region, surveys on pig density and N,P inputs to farmlands, soil N and P contents, and annual observations of the N and P flows in the streams and the terminal river were carried out in a hilly watershed (134.4 km2 ) in Changsha County, Hunan Province. It was showed that the total NP loads from the watershed to the terminal river was 2.72 t and 0. 11 t·km-2·a-1, respectively ; within which 42. 2% of the N and 62. 0% of

  18. Evaluation of Carrying Capacity Land-Based Layout to Mitigate Flood Risk (Case Study in Tempuran Floodplain, Ponorogo Regency) Novia Lusiana1 Bambang Rahadi2 Tunggul Sutanhaji3 1Environmental and Natural Resources Management Graduate Program University of Brawijaya, Malang, Indonesia 23Laboratory of Environment and Natural Resources Engineering, Department of Agricultural Engineering, Faculty of Agricultural Technology, University of Brawijaya, Malang, Indonesia Email : novialusiana@rocketmail.com, jbrahadi@ub.ac.id, tunggulsutanhaji@yahoo.com

    Science.gov (United States)

    Lusiana, N.

    2013-12-01

    Abstract Floods haves frequently hit Indonesia and have had greater negative impacts. In Javaboth the area affected by flooding and the amount of damage caused by floods have increased. At least, five factors, affect the flooding in Indonesia, including rainfall, reduced retention capacity of the watershed, erroneous design of river channel development, silting-up of the river, and erroneous regional layout. The level of the disastrous risks can be evaluated based on the extent of the threat and susceptibility of a region. One methode for risk assessment is Geographical Information System (GIS)-based mapping. Objectives of this research are: 1) evaluating current flood risk in susceptible areas, 2) applying supported land-based layout as effort to mitigate floodrisk, and 3) evaluating floodrisk for the period 2031 in the Tempuran floodplain of Ponorogo Regency. Result show that the area categorized as high risk covers 104. 6 ha (1. 2%), moderate risk covers 2512. 9 ha (28. 4%), low risk covers 3140. 8 ha (35. 5%), and the lowest risk covers 3096. 1 (34. 9%). Using Regional Layout Design for the years 2011 - 2031, the high risk area covers 67. 9 ha (0.8%), moderate risk covers 3033 ha (34. 3%), low risk covers 2770. 8 ha (31, 3%), and the lowest risk covers 2982. 6 ha (34%). Based on supported land suitability, the high-risk areais only 2. 9 ha (0.1%), moderate risk covers of 426. 1 ha (4. 8%), low risk covers 4207. 4 ha (47. 5%), and the lowest risk covers 4218 ha (47. 6%). Flood risk can be mitigated by applying supported land-based layout as shown by the reduced high-risk area, and the fact that > 90% of the areas are categorized as low or lowest risk of disaster. Keywords : Carrying Capacity, Land Capacity, Flood Risk

  19. Capacitated Dynamic Lot Sizing with Capacity Acquisition

    DEFF Research Database (Denmark)

    Li, Hongyan; Meissner, Joern

    One of the fundamental problems in operations management is to determine the optimal investment in capacity. Capacity investment consumes resources and the decision is often irreversible. Moreover, the available capacity level affects the action space for production and inventory planning decisions...... with inventory carrying costs. The production per period limited by a capacity restriction. The underlying capacity must be purchased up front for the upcoming season and remains constant over the entire season. We assume that the capacity acquisition cost is smooth and convex. For this situation, we develop...

  20. Capacity fade of Sony 18650 cells cycled at elevated temperatures. Part II. Capacity fade analysis

    Science.gov (United States)

    Ramadass, P.; Haran, Bala; White, Ralph; Popov, Branko N.

    A complete capacity fade analysis was carried out for Sony 18650 cells cycled at elevated temperatures. The major causes of capacity loss were identified and a complete capacity fade balance was carried out to account for the total capacity loss of Li-ion battery as a function of cycle number and temperature. The three most significant parameters that cause capacity loss were loss of secondary active material (LiCoO 2/carbon) and primary active material (Li +) and the rate capability losses. Intrinsic capacity measurements for both positive and negative electrode has been used to estimate the capacity loss due to secondary active material and a charge balance gives the capacity lost due to primary active material (Li +). Capacity fade has been quantified with secondary active material loss dominating the other losses.