WorldWideScience

Sample records for current carrying capacity

  1. 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...

  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...... 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...

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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...

  8. 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...

  9. 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...

  10. 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

  11. 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

  12. 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.

  13. 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 ...

  14. 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.

  15. 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.

  16. 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.

  17. 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...

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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 ...

  9. 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...

  10. 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.

  11. 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.

  12. 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.

  13. 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...

  14. 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.

  15. 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.

  16. 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…

  17. 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...

  18. 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.

  19. 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.

  20. Radial excitations of current-carrying vortices

    Science.gov (United States)

    Hartmann, Betti; Michel, Florent; Peter, Patrick

    2017-04-01

    We report on the existence of a new type of cosmic string solutions in the Witten model with U (1) × U (1) symmetry. These solutions are superconducting with radially excited condensates that exist for both gauged and ungauged currents. Our results suggest that these new configurations can be macroscopically stable, but microscopically unstable to radial perturbations. Nevertheless, they might have important consequences for the network evolution and particle emission. We discuss these effects and their possible signatures. We also comment on analogies with non-relativistic condensed matter systems where these solutions may be observable.

  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. 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.

  3. 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.

  4. 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...

  5. 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.

  6. 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...

  7. 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

  8. 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.

  9. [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.

  10. 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

  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. Magnetically Guiding Atoms with Current-Carrying Conductors

    Institute of Scientific and Technical Information of China (English)

    刘南春; 高伟建; 印建平

    2002-01-01

    We propose a novel magnetic guide for cold neutral atoms using some current-carrying conductors. The spatial distributions of the magnetic fields from a V-shaped or U-shaped current-carrying conductor are calculated, and the relationship between the resulting magnetic field and the parameters of the current-carrying conductors is analysed in detail. The result shows that these current-carrying conductors can be used to realize a single or a controllable double magnetic guide of cold atoms in the weak-field-seeking state, and to construct various atom-optical elements, and even to realize a single-mode atomic waveguiding under certain conditions.

  13. 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.

  14. Measuring the Magnetic Force on a Current-Carrying Conductor.

    Science.gov (United States)

    Herreman, W.; Huysentruyt, R.

    1995-01-01

    Describes a fast and simple method for measuring the magnetic force acting on a current-carrying conductor using a digital balance. Discusses the influence of current intensity and wire length on the magnetic force on the conductor. (JRH)

  15. 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,...

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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...

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Wakes in Dilatonic Current-Carrying Cosmic Strings

    CERN Document Server

    Oliveira, A L N

    2003-01-01

    In this work, we present the gravitational field generated by a cosmic string carrying a timelike current in the scalar-tensor gravities. The mechanism of formation and evolution of wakes is fully investigated in this framework. We show that the inclusion of electromagnetic properties for the string induces logarithmic divergences in the accretion problem.

  10. 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...

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. [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.

  16. 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.

  17. 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.

  18. 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.

  19. 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...

  20. 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.

  1. 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...

  2. 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...

  3. 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 ...

  4. 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.…

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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".

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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...

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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)

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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...

  12. 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.

  13. Magnetization of a Current-Carrying Superconducting Disk with B-Dependent Critical Current Density

    Science.gov (United States)

    Sohrabi, Mahdi; Babaei-Brojeny, Ali A.

    2010-11-01

    In the frame work of the critical state model (CSM), the magnetic response of a thin type-II superconducting disk that carries a radial transport current and is subjected to an applied magnetic field have been studied. To this end, we have studied the process of the magnetic flux-penetration. For a disk initially containing no magnetic flux but carrying a radial current, when a perpendicular magnetic field is applied, magnetic flux-penetration occurs in three stages: (1) the magnetic flux gradually penetrates from the edges of the disk until an instability occurs, (2) there is a rapid inflow of magnetic flux into the disk’s central region, which becomes resistive, and (3) magnetic flux continues to enter the disk, while persistent azimuthal currents flow in an outer annular region where the net current density is equal to J c . Also the behavior of a current-carrying disk subjected to an AC magnetic field is calculated. The magnetic flux, the current profiles and the magnetization hysteresis loops are calculated for several commonly used J c ( B) dependences. Finally, the results of the applications of the local field-dependent of the critical current density J c ( B) are compared with those obtained from the Bean model.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. [Organ cryopreservation: current status of research carried out in Grenoble].

    Science.gov (United States)

    Descotes, J L; Payen, E; Rambeaud, J J; Peuridieu, J F; Baudot, A; Odin, J; Mazuer, J; Boutron, P; Delon-Martin, C; Dupeyre, R

    1995-12-01

    After discussing the problem of organ cryopreservation and reviewing the current data available on this subject, the Grenoble project is presented. Physical and biological studies have been combined with experimentation of autologous renal transplantation in rabbits to assess the functional value of the retransplanted organ after treatment and cooling. Renal resistances are measured during perfusion of the kidney with the cryoprotective solution. In order to verify the homogeneity of the cryoprotector concentration in the organ, on NMR spectral imaging test has been developed. A new rapid imaging method now allows real time monitoring of concentration variations during perfusion. In addition to concentration and homogeneity, analysis of local spectra also provides information about the local temperature de the kidney.

  7. Eddy current quality control of soldered current-carrying busbar splices of superconducting magnets

    CERN Document Server

    Kogan, L; Savary, F; Principe, R; Datskov, V; Rozenfel'd, E; Khudjakov, B

    2015-01-01

    The eddy current technique associated with a U-shaped transducer is studied for the quality control of soldered joints between superconducting busbars ('splices'). Two other quality control techniques, based on X-rays and direct measurement of the electrical resistance, are also studied for comparison. A comparative analysis of the advantages and disadvantages of these three methods in relation to the quality control of soldered superconducting busbar cables enclosed in copper shells is used for benchmarking. The results of inspections with the U-shaped eddy current transducer carried out on several sample joints presenting different types of soldering defects show the potential of this type of nondestructive (ND) quality control technique.

  8. 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

  9. 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...

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. [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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Formation of current filaments and magnetic field generation in a quantum current-carrying plasma

    Energy Technology Data Exchange (ETDEWEB)

    Niknam, A. R. [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran (Iran, Islamic Republic of); Taghadosi, M. R.; Majedi, S.; Khorashadizadeh, S. M. [Physics Department, University of Birjand, Birjand (Iran, Islamic Republic of)

    2013-09-15

    The nonlinear dynamics of filamentation instability and magnetic field in a current-carrying plasma is investigated in the presence of quantum effects using the quantum hydrodynamic model. A new nonlinear partial differential equation is obtained for the spatiotemporal evolution of the magnetic field in the diffusion regime. This equation is solved by applying the Adomian decomposition method, and then the profiles of magnetic field and electron density are plotted. It is shown that the saturation time of filamentation instability increases and, consequently, the instability growth rate and the magnetic field amplitude decrease in the presence of quantum effects.

  3. 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.

  4. 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.

  5. 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.

  6. 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....

  7. 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...

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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...

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. 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

  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. 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

  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. 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.

  5. 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.

  6. 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.

  7. 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";}

  8. 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.

  9. (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...

  10. 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。

  11. 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.

  12. 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

  13. 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)

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. 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

  5. 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.

  6. 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

  7. On the theory of the electric field and current density in a superconductor carrying transport current

    Energy Technology Data Exchange (ETDEWEB)

    Carr, W.J. [LEI 700 Technology Dr., Pittsburgh, PA 15219 (United States)]. E-mail: wjamescarrjr@att.net

    2005-09-15

    A theory is given to explain the physics behind the flow of low-frequency ac transport current around a closed superconducting circuit, where the circuit consists of two long, straight, parallel, uniform conductors, connected to each other at one end and to an applied emf at the other end. Thus one conductor is the return path for the other. A question of interest is what drives the current at any given point in the circuit. The answer given here is a surface charge, where the purpose of the surface charge is to spread the local emf around the circuit, so that at each point in the conductor it produces, together with the electric field of the vector potential, the electric field necessary for the current to flow. But it is then necessary to explain how the surface charge gets there, which is the central problem of the present analysis. The conclusion is that the total current density consists of the superposition of a large transport current and a very much smaller current system of a different symmetry. The transport current density is defined as a two-dimensional current density with no divergence. It flows uniformly along the conductor length, but can vary over the cross-section. The small additional current density has a much different symmetry, being three-dimensional and diverging at the surface of the conductor. Based on a slightly modified Bean model the transport current is treated as supercurrent having the value {+-}J {sub c}, while the small additional system of current is like normal current, with a density given by the electric field divided by a resistivity. The electric field is computed from the sum of the negative time derivative of the vector potential and the negative gradient of the scalar potential due to the surface charge. It has components parallel and perpendicular to the long axis of the conductor. Thus the small normal current density has a perpendicular component which flows into or out of the surface thereby creating the surface charge

  8. 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.

  9. Magnetic guide of cold atoms using a U-shaped current-carrying conductor

    Institute of Scientific and Technical Information of China (English)

    刘南春; 印建平

    2003-01-01

    We propose a new scheme to magnetically guide cold neutral atoms using a U-shaped current carrying conductor.The spatial magnetic field distribution from the U-shaped current-carrying conductor and the relationship between the magnetic field and parameters of the U-shaped conductor are analysed.Our study shows that U-shaped current-carrying conductor can be used to realize single-or double-channel magnetic guiding of cold atoms in weak-field-seeking states and to construct wrious atom-optical elements.By using Monte Carlo simulations,the dynamic process of the guided atomic-beam splitting in an atomic-beam splitter composed by the U-shaped current-carrying conductor is studied,and some results are presented.

  10. Surface barrier effect on magnetization of a current-carrying type-II superconductor

    Science.gov (United States)

    Genenko, Yu. A.; Freyhardt, H. C.

    2000-10-01

    Vortex penetration in and exit from ideal flux-filled current-carrying superconductors are studied in the frame of the modified Meissner state model accounting for the vortex interactions with the sample surface, transport current, external field and the other vortices inside the sample. The generalized Silsbee's rule is first formulated and the M- H diagram of ideal current-carrying superconductors in a parallel field is estimated which is irreversible due to the surface effect alone. In general, magnetic behaviour of superconductors is shown to be more reversible in the presence of a transport current.

  11. 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.

  12. High-capacity thick cathode with a porous aluminum current collector for lithium secondary batteries

    Science.gov (United States)

    Abe, Hidetoshi; Kubota, Masaaki; Nemoto, Miyu; Masuda, Yosuke; Tanaka, Yuichi; Munakata, Hirokazu; Kanamura, Kiyoshi

    2016-12-01

    A high-capacity thick cathode has been studied as one of ways to improve the energy density of lithium secondary batteries. In this study, the LiFePO4 cathode with a capacity per unit area of 8.4 m Ah cm-2 corresponding to four times the capacity of conventional cathodes has been developed using a three-dimensional porous aluminum current collector called "FUSPOROUS". This unique current collector enables the smooth transfer of electrons and Li+-ions through the thick cathode, resulting in a good rate capability (discharge capacity ratio of 1.0 C/0.2 C = 0.980) and a high charge-discharge cycle performance (80% of the initial capacity at 2000th cycle) even though the electrode thickness is 400 μm. To take practical advantage of the developed thick cathode, conceptual designs for a 10-Ah class cell were also carried out using graphite and lithium-metal anodes.

  13. 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...

  14. 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.

  15. 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.

  16. 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…

  17. 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...

  18. 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...

  19. 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.

  20. 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...

  1. 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....

  2. 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…

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. 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).

  12. 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.

  13. 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...

  14. 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...

  15. Beach Carrying Capacity Analysis for Sustainable Tourism Development in the South West Coast of India

    OpenAIRE

    Brilliant Rajan; Vincy Mary Varghese; Anakkathil Purushothaman Pradeepkumar

    2013-01-01

    The rapid growth of coastal tourism that has been seen in the last 10 years is frequently described as one of the major reasons for the development of these areas and also is responsible for many current coastal problems. The beaches perform, in this context, a fundamental role, where the issues related to planning and management are increasingly more important when it comes to an implementation of a sustainable development philosophy. In Kerala, where coastal tourism plays a major part of th...

  16. 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

  17. Charged Particle Dynamics in the Magnetic Field of a Long Straight Current-Carrying Wire

    Science.gov (United States)

    Prentice, A.; Fatuzzo, M.; Toepker, T.

    2015-01-01

    By describing the motion of a charged particle in the well-known nonuniform field of a current-carrying long straight wire, a variety of teaching/learning opportunities are described: 1) Brief review of a standard problem; 2) Vector analysis; 3) Dimensionless variables; 4) Coupled differential equations; 5) Numerical solutions.

  18. 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.

  19. [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.

  20. 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).

  1. Potential effects of drought on carrying capacity for wintering waterfowl in the Central Valley of California

    Science.gov (United States)

    Petrie, Mark J.; Fleskes, Joseph P.; Wolder, Mike A.; Isola, Craig R.; Yarris, Gregory S.; Skalos, Daniel A.

    2016-01-01

    We used the bioenergetics model TRUEMET to evaluate potential effects of California's recent drought on food supplies for waterfowl wintering in the Central Valley under a range of habitat and waterfowl population scenarios. In nondrought years in the current Central Valley landscape, food supplies are projected to be adequate for waterfowl from fall through early spring (except late March) even if waterfowl populations reach North American Waterfowl Management Plan goals. However, in all drought scenarios that we evaluated, food supplies were projected to be exhausted for ducks by mid- to late winter and by late winter or early spring for geese. For ducks, these results were strongly related to projected declines in winter-flooded rice fields that provide 45% of all the food energy available to ducks in the Central Valley in nondrought water years. Delayed flooding of some managed wetlands may help alleviate food shortages by providing wetland food resources better timed with waterfowl migration and abundance patterns in the Central Valley, as well as reducing the amount of water needed to manage these habitats. However, future research is needed to evaluate the impacts of delayed flooding on waterfowl hunting, and whether California's existing water delivery system would make delayed flooding feasible. Securing adequate water supplies for waterfowl and other wetland-dependent birds is among the greatest challenges facing resource managers in coming years, especially in the increasingly arid western United States.

  2. Sausage instabilities on top of kinking lengthening current-carrying magnetic flux tubes

    Science.gov (United States)

    von der Linden, Jens; You, Setthivoine

    2017-05-01

    We theoretically explore the possibility of sausage instabilities developing on top of a kink instability in lengthening current-carrying magnetic flux tubes. Observations indicate that the dynamics of magnetic flux tubes in our cosmos and terrestrial experiments can involve topological changes faster than time scales predicted by resistive magnetohydrodynamics. Recent laboratory experiments suggest that hierarchies of instabilities, such as kink and Rayleigh-Taylor, could be responsible for initiating fast topological changes by locally accessing two-fluid and kinetic regimes. Sausage instabilities can also provide this coupling mechanism between disparate scales. Flux tube experiments can be classified by the flux tube's evolution in a configuration space described by a normalized inverse aspect-ratio k ¯ and current-to-magnetic flux ratio λ ¯ . A lengthening current-carrying magnetic flux tube traverses this k ¯ - λ ¯ space and crosses stability boundaries. We derive a single general criterion for the onset of the sausage and kink instabilities in idealized magnetic flux tubes with core and skin currents. The criterion indicates a dependence of the stability boundaries on current profiles and shows overlapping kink and sausage unstable regions in the k ¯ - λ ¯ space with two free parameters. Numerical investigation of the stability criterion reduces the number of free parameters to a single one that describes the current profile and confirms the overlapping sausage and kink unstable regions in k ¯ - λ ¯ space. A lengthening, ideal current-carrying magnetic flux tube can therefore become sausage unstable after it becomes kink unstable.

  3. 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.

  4. Magnetic focusing of cold atomic beam with a 2D array of current-carrying wires

    Institute of Scientific and Technical Information of China (English)

    Yang Liu; Min Yun; Jianping Yin

    2006-01-01

    @@ A new scheme to realize a two-dimensional (2D) array of magnetic micro-lenses for a cold atomic beam,formed by an array of square current-carrying wires,is proposed.We calculate the spatial distributions of the magnetic fields from the array of current-carrying wires and the magnetic focusing potential for cold rubidium atoms,and study the dynamic focusing processes of cold atoms passing through the magnetic micro-lens array and its focusing properties by using Monte-Carlo simulations and trajectory tracing method.The result shows that the proposed micro-lens array can be used to focus effectively a cold atomic beam,even to load ultracold atoms or a BEC sample into a 2D optical lattice formed by blue detuned hollow beams.

  5. Magnetic Field Due to a Finite Length Current-Carrying Wire Using the Concept of Displacement Current

    Science.gov (United States)

    Buschauer, Robert

    2014-01-01

    In undergraduate E&M courses the magnetic field due to a finite length, current-carrying wire can be calculated using the Biot-Savart law. However, to the author's knowledge, no textbook presents the calculation of this field using the Ampere-Maxwell law: ?B [multiplied by] dl = µ[subscript 0] (I + e[subscript 0] dF/dt) [multiplied by] 1

  6. The Regional Advisory Councils' current capacities and unforeseen benefits

    DEFF Research Database (Denmark)

    Ounanian, Kristen; Hegland, Troels Jacob

    2012-01-01

    as not going far enough to alleviate problems of lagging process and content legitimacy, in certain ways the RACs may be thought of as representing an interim institutional stage, facilitating better information sharing and cultivating stakeholder relationships. Based on a survey of RAC participants......, this paper illuminates the current capacities and functions of the RACs. The paper reveals that the RACs possess additional--often not sufficiently recognised--roles and values to the advice they produce as they facilitate understanding across and within sectors and interest groups and act as key purveyors...

  7. 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.

  8. 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.

  9. [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

  10. Sharp burnout failure observed in high current-carrying double-walled carbon nanotube fibers

    Science.gov (United States)

    Song, Li; Toth, Geza; Wei, Jinquan; Liu, Zheng; Gao, Wei; Ci, Lijie; Vajtai, Robert; Endo, Morinobu; Ajayan, Pulickel M.

    2012-01-01

    We report on the current-carrying capability and the high-current-induced thermal burnout failure modes of 5-20 µm diameter double-walled carbon nanotube (DWNT) fibers made by an improved dry-spinning method. It is found that the electrical conductivity and maximum current-carrying capability for these DWNT fibers can reach up to 5.9 × 105 S m - 1 and over 1 × 105 A cm - 2 in air. In comparison, we observed that standard carbon fiber tended to be oxidized and burnt out into cheese-like morphology when the maximum current was reached, while DWNT fiber showed a much slower breakdown behavior due to the gradual burnout in individual nanotubes. The electron microscopy observations further confirmed that the failure process of DWNT fibers occurs at localized positions, and while the individual nanotubes burn they also get aligned due to local high temperature and electrostatic field. In addition a finite element model was constructed to gain better understanding of the failure behavior of DWNT fibers.

  11. 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)

  12. Sausage Instabilities on top of Kinking Lengthening Current-Carrying Magnetic Flux Tubes

    Science.gov (United States)

    von der Linden, Jens; You, Setthivoine

    2015-11-01

    Observations indicate that the dynamics of magnetic flux tubes in our cosmos and terrestrial experiments involve fast topological change beyond MHD reconnection. Recent experiments suggest that hierarchies of instabilities coupling disparate plasma scales could be responsible for this fast topological change by accessing two-fluid and kinetic scales. This study will explore the possibility of sausage instabilities developing on top of a kink instability in lengthening current-carrying magnetic flux tubes. Current driven flux tubes evolve over a wide range of aspect ratios k and current to magnetic flux ratios λ . An analytical stability criterion and numerical investigations, based on applying Newcomb's variational approach to idealized magnetic flux tubes with core and skin currents, indicate a dependence of the stability boundaries on current profiles and overlapping kink and sausage unstable regions in the k - λ trajectory of the flux tubes. A triple electrode planar plasma gun (Mochi.LabJet) is designed to generate flux tubes with discrete core and skin currents. Measurements from a fast-framing camera and a high resolution magnetic probe are being assembled into stability maps of the k - λ space of flux tubes. This work was sponsored in part by the US DOE Grant DE-SC0010340.

  13. AC losses in monofilamentary MgB{sub 2} round wire carrying alternating transport currents

    Energy Technology Data Exchange (ETDEWEB)

    Kajikawa, K [Research Institute of Superconductor Science and Systems, Kyushu University, Fukuoka 819-0395 (Japan); Kawano, T [Department of Electrical and Electronic Systems Engineering, Kyushu University, Fukuoka 819-0395 (Japan); Osaka, R [Department of Electrical Engineering, Kyushu University, Fukuoka 819-0395 (Japan); Nakamura, T [Department of Electrical Engineering, Kyoto University, Kyoto 615-8510 (Japan); Sugano, M [Department of Electronic Science and Engineering, Kyoto University, Kyoto 615-8510 (Japan); Takahashi, M; Wakuda, T, E-mail: kajikawa@sc.kyushu-u.ac.j [Hitachi Research Laboratory, Hitachi, Ltd, Hitachi 319-1292 (Japan)

    2010-04-15

    AC losses in a monofilamentary MgB{sub 2} round wire with niobium and copper metal sheaths and carrying alternating transport currents are evaluated at several temperatures and frequencies. First, the transport current losses are observed electrically using a lock-in amplifier. Experimental results show that the AC losses decrease with an increase in the temperature if the amplitude of the transport current normalized by the corresponding critical current is maintained constant. On the other hand, the AC losses increase slightly with the frequency. Next, the AC losses are calculated numerically by a finite difference method. The numerical results for the superconductor filament show a good agreement with the results of the conventional theoretical expression formulated using the Bean model over a wide range of current amplitudes. It is also found that the AC losses in the niobium sheath are negligible whereas those in the copper sheath are comparable with those in the superconductor. On the basis of the numerical calculations, an expression is analytically derived for estimating the eddy current loss occurring in a metal sheath. The derived expression well reproduces the AC loss properties of both the copper and niobium sheaths.

  14. AC losses in monofilamentary MgB2 round wire carrying alternating transport currents

    Science.gov (United States)

    Kajikawa, K.; Kawano, T.; Osaka, R.; Nakamura, T.; Sugano, M.; Takahashi, M.; Wakuda, T.

    2010-04-01

    AC losses in a monofilamentary MgB2 round wire with niobium and copper metal sheaths and carrying alternating transport currents are evaluated at several temperatures and frequencies. First, the transport current losses are observed electrically using a lock-in amplifier. Experimental results show that the AC losses decrease with an increase in the temperature if the amplitude of the transport current normalized by the corresponding critical current is maintained constant. On the other hand, the AC losses increase slightly with the frequency. Next, the AC losses are calculated numerically by a finite difference method. The numerical results for the superconductor filament show a good agreement with the results of the conventional theoretical expression formulated using the Bean model over a wide range of current amplitudes. It is also found that the AC losses in the niobium sheath are negligible whereas those in the copper sheath are comparable with those in the superconductor. On the basis of the numerical calculations, an expression is analytically derived for estimating the eddy current loss occurring in a metal sheath. The derived expression well reproduces the AC loss properties of both the copper and niobium sheaths.

  15. 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.

  16. Acceleration of magnetic dipoles by a sequence of current-carrying turns

    Science.gov (United States)

    Dolya, S. N.

    2014-11-01

    Magnetic dipoles are accelerated by a running gradient of the magnetic field that is produced by sequentially energizing current-carrying turns. Magnetic dipoles d sh = 60 mm in diameter and l tot = 1 m in length are gasdynamically preaccelerated to velocity V in = 1 km/s, with which they are injected into the main accelerator. The turnover of the dipoles in the field of an accelerating pulse is prevented and focusing of dipoles is provided by directing the dipoles into a titanium tube. The weight of the dipoles is m = 2 kg, and they acquire final velocity V fin = 5 km/s over acceleration length L acc = 300 m.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. MAGNETIC-ELASTIC BUCKLING OF A THIN CURRENT CARRYING PLATE SIMPLY SUPPORTED AT THREE EDGES

    Institute of Scientific and Technical Information of China (English)

    WANG Zhiren; WANG Ping; BAI Xiangzhong

    2008-01-01

    The magnetic-elasticity buckling problem of a current plate under the action of a mechanical load in a magnetic field was studied by using the Mathieu function. According to the magnetic-elasticity non-linear kinetic equation, physical equations, geometric equations, the expression for Lorenz force and the electrical dynamic equation, the magnetic-elasticity dynamic buckling equation is derived. The equation is changed into a standard form of the Mathieu equation using Galerkin's method. Thus, the buckling problem can be solved with a Mathieu equation. The criterion equation of the buckling problem also has been obtained by discussing the eigenvalue relation of the coefficients λ and η in the Mathieu equation. As an example, a thin plate simply supported at three edges is solved here. Its magnetic-elasticity dynamic buckling equation and the relation curves of the instability state with variations in some parameters are also shown in this paper. The conclusions show that the electrical magnetic forces may be controlled by changing the parameters of the current or the magnetic field so that the aim of controlling the deformation, stress, strain and stability of the current carrying plate is achieved.

  3. The structure of fast sausage waves in current-carrying coronal loops

    Science.gov (United States)

    Bembitov, D. B.; Mikhalyaev, B. B.; Ruderman, M. S.

    2014-09-01

    We study fast sausage waves in a model coronal loop that consists of a cylindrical core with axial magnetic field and coaxial annulus with purely azimuthal magnetic field. The magnetic field is discontinuous at the tube and core boundaries, and there are surface currents with the opposite directions on these boundaries. The principal mode of fast sausage waves in which the magnetic pressure perturbation has no nodes in the radial direction can exist for arbitrary wavelength. The results for the fundamental radial mode of sausage waves are applied to the interpretation of observed periodic pulsations of microwave emission in flaring loops with periods of a few tens of seconds. Radial plasma motion has opposite directions at the tube and core boundaries. This leads to the periodic contraction and expansion of the annulus. We assume that the principal mode of fast sausage waves in the current-carrying coronal loops is able to produce a current sheet. However, the nonlinear analysis is needed to confirm this conjecture.

  4. Liquid nitrogen cooled integrated power electronics module with high current carrying capability and lower on resistance

    Science.gov (United States)

    Ye, Hua; Lee, Changwoo; Simon, Randy W.; Haldar, Pradeep; Hennessy, Michael J.; Mueller, Eduard K.

    2006-11-01

    This letter presents the development of high-performance integrated cryogenic power modules, where both driver components and power metal-oxide semiconductor field-effect transistors are integrated in a single package, to be used in a 50kW prototype cryogenic inverter operating at liquid nitrogen temperature. The authors have demonstrated a compact high-voltage, cryogenic integrated power module that exhibited more than 14 times improvement in on-resistance and continuous current carrying capability exceeding 40A. The modules are designed to operate at liquid nitrogen temperature with extreme thermal cycling. The power electronic modules are necessary components that provide control and switching for second generation, yttrium barium copper oxide-based high temperature superconductor devices including cables, motors, and generators.

  5. Thermal Model of a Current-Carrying Wire in a Vacuum

    Science.gov (United States)

    Border, James

    2006-01-01

    A computer program implements a thermal model of an insulated wire carrying electric current and surrounded by a vacuum. The model includes the effects of Joule heating, conduction of heat along the wire, and radiation of heat from the outer surface of the insulation on the wire. The model takes account of the temperature dependences of the thermal and electrical properties of the wire, the emissivity of the insulation, and the possibility that not only can temperature vary along the wire but, in addition, the ends of the wire can be thermally grounded at different temperatures. The resulting second-order differential equation for the steady-state temperature as a function of position along the wire is highly nonlinear. The wire is discretized along its length, and the equation is solved numerically by use of an iterative algorithm that utilizes a multidimensional version of the Newton-Raphson method.

  6. Phonon induced optical gain in a current carrying two-level quantum dot

    Energy Technology Data Exchange (ETDEWEB)

    Eskandari-asl, Amir, E-mail: amir.eskandari.asl@gmail.com [Department of Physics, Shahid Beheshti University, G.C. Evin, Tehran 1983963113 (Iran, Islamic Republic of); School of Nano Science, Institute for Research in Fundamental Sciences (IPM), P.O. Box: 19395-5531, Tehran, Iran (Iran, Islamic Republic of)

    2017-05-15

    In this work we consider a current carrying two level quantum dot (QD) that is coupled to a single mode phonon bath. Using self-consistent Hartree-Fock approximation, we obtain the I-V curve of QD. By considering the linear response of our system to an incoming classical light, we see that depending on the parametric regime, the system could have weak or strong light absorption or may even show lasing. This lasing occurs at high enough bias voltages and is explained by a population inversion considering side bands, while the total electron population in the higher level is less than the lower one. The frequency at which we have the most significant lasing depends on the level spacing and phonon frequency and not on the electron-phonon coupling strength.

  7. Suppression of vertical instability in elongated current-carrying plasmas by applying stellarator rotational transform

    Energy Technology Data Exchange (ETDEWEB)

    ArchMiller, M. C.; Cianciosa, M. R.; Ennis, D. A.; Hanson, J. D.; Hartwell, G. J.; Hebert, J. D.; Herfindal, J. L.; Knowlton, S. F.; Ma, X.; Maurer, D. A.; Pandya, M. D.; Traverso, P. [Physics Department, Auburn University, Auburn, Alabama 36849 (United States)

    2014-05-15

    The passive stability of vertically elongated current-carrying toroidal plasmas has been investigated in the Compact Toroidal Hybrid, a stellarator/tokamak hybrid device. In this experiment, the fractional transform f, defined as the ratio of the imposed external rotational transform from stellarator coils to the total rotational transform, was varied from 0.04 to 0.50, and the elongation κ was varied from 1.4 to 2.2. Plasmas that were vertically unstable were evidenced by motion of the plasma in the vertical direction. Vertical drifts are measured with a set of poloidal field pickup coils. A three chord horizontally viewing interferometer and a soft X-ray diode array confirmed the drifts. Plasmas with low fractional transform and high elongation are the most susceptible to vertical instability, consistent with analytic predictions that the vertical mode in elongated plasmas can be stabilized by the poloidal field of a relatively weak stellarator equilibrium.

  8. 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.

  9. 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

  10. 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.

  11. Is follow-up capacity the current NHS bottleneck?

    Science.gov (United States)

    Allder, Steven; Walley, Paul; Silvester, Kate

    2011-02-01

    Capacity and demand theory suggests that the presence of a queue is not necessarily an indication of a shortage of capacity in a system. It is much more likely that either there is a demand and capacity variation that creates queues or there is a delay designed into the system. A shortage of capacity is only really indicated where a backlog is not stable and continues to grow. In this article, data are taken from one NHS trust that provides evidence for a continually growing backlog for follow-up outpatient services. It is believed that these data are representative of most locations within the NHS in England and therefore suggest an immediate shortage in effective follow-up capacity. To avoid compromise to patient care, the problem will have to be addressed before the situation becomes unmanageable. The paper highlights options to reduce or deflect demand or to increase effective capacity.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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...

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Ion-Cyclotron Instability in Current-Carrying Lorentzian (Kappa) and Maxwellian Plasmas with Anisotropic Temperatures: A Comparative Study

    Science.gov (United States)

    2011-09-26

    in the solar wind and in many space plasmas often exhibit non - Maxwellian suprathermal tails that decrease as a power-law of the velocity.1 Such...AFRL-RV-PS- AFRL-RV-PS- TR-2011-0164 TR-2011-0164 ION-CYCLOTRON INSTABILITY IN CURRENT- CARRYING LORENTZIAN (KAPPA) AND MAXWELLIAN PLASMAS...1 Oct 2007 – 9 Sep 2011 4. TITLE AND SUBTITLE Ion-Cyclotron Instability in Current-Carrying Lorentzian (Kappa) and Maxwellian Plasmas 5a. CONTRACT

  8. Comparing a current-carrying circular wire with polygons of equal perimeter; Magnetic field versus magnetic flux

    OpenAIRE

    J P Silva; Silvestre, A. J.

    2006-01-01

    We compare the magnetic field at the center of and the self-magnetic flux through a current-carrying circular loop, with those obtained for current-carrying polygons with the same perimeter. As the magnetic field diverges at the position of the wires, we compare the self-fluxes utilizing several regularization procedures. The calculation is best performed utilizing the vector potential, thus highlighting its usefulness in practical applications. Our analysis answers some of the intuition chal...

  9. Guiding Neutral Atoms with Two Current-Carrying Wires and a Vertical Bias Field on the Atom Chip

    Institute of Scientific and Technical Information of China (English)

    KE Min; YAN Bo; LI Xiao-Lin; WANG Yu-Zhu

    2008-01-01

    @@ We demonstrate the guiding of neutral atoms with two parallel microfabricated current-carrying wires on the atom chip and a verticai magnetic bias field.The atoms are guided along a magnetic field minimum parallel to the current-carrying wires and confined in the other two directions.We describe in detail how the precooled atoms are efficiently loaded into the two-wire guide.

  10. 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

  11. Modelling and simulation of the ice melting process on a current-carrying conductor

    Energy Technology Data Exchange (ETDEWEB)

    Peter, Z.

    2006-07-01

    Mathematical models were developed to determine the current and energy requirements for thermal de-icing and ice prevention on overhead power transmission lines. The models were based on the Joule effect under various meteorological and current transmission conditions. The minimum current intensity required to inhibit ice formation on a single power line conductor was determined. Correction factors were then introduced for 3 specific aluminum conductors with steel reinforcement (ACSRs). Water runback on the conductor surface was considered as well as deviation of the water layer from the thermal equilibrium state. Model results were in good agreement with measurements taken in an icing research wind tunnel. The overall heat transfer coefficient (HTC) for stranded conductors was then assessed to complete the model. A computational model using finite differences was also developed to calculate the current and energy requirements for de-icing partially ice covered conductors. Joule heating by AC current and impulse current were the 2 heating techniques analyzed. Thermal conductivity of the ACSR conductor was also estimated. Experimentally validated analytical approaches were proposed to determine the shedding time and corresponding energy required to de-ice a completely ice covered conductor by heating with increased nominal AC current. It was concluded that ice accretion on a single power line can be prevented using the experimentally validated mathematical models that calculate the current and energy requirements of de-icing conductors.

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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...

  18. Electron heat transport in current carrying and currentless thermonuclear plasmas. Tokamaks and stellarators compared

    Energy Technology Data Exchange (ETDEWEB)

    Peters, M.

    1996-01-16

    In the first experiment the plasma current in the RTP tokamak is varied. Here the underlying idea was to check whether at a low plasma current, transport in the tokamak resembles transport in stellarators more than at higher currents. Secondly, experiments have been done to study the relation of the diffusivity {chi} to the temperature and its gradient in both W7-AS and RTP. In this case the underlying idea was to find the explanation for the phenomenon observed in both tokamaks and stellarators that the quality of the confinement degrades when more heating is applied. A possible explanation is that the diffusivity increases with the temperature or its gradient. Whereas in standard tokamak and stellarator experiments the temperature and its gradient are strongly correlated, a special capability of the plasma heating system of W7-AS and RTP can force them to decouple. (orig.).

  19. On the Behaviour of Current-Carrying Wire-Conductors and Bucking of a Column

    DEFF Research Database (Denmark)

    Ganji, S. S.; Barari, Amin; Fereidoon, A.

    2013-01-01

    -conductors and bucking of a column as well as their comparisons with the exact solutions are presented. Different specific parameters and initial values comprising the mass and stiffness are studied within the current research and excellent accuracy which is the most significant feature of the proposed solutions...

  20. Random phase approximation with second-order screened exchange for current-carrying atomic states

    Science.gov (United States)

    Zhu, Wuming; Zhang, Liang; Trickey, S. B.

    2016-12-01

    The direct random phase approximation (RPA) and RPA with second-order screened exchange (SOSEX) have been implemented with complex orbitals as a basis for treating open-shell atoms. Both RPA and RPA+SOSEX are natural implicit current density functionals because the paramagnetic current density implicitly is included through the use of complex orbitals. We confirm that inclusion of the SOSEX correction improves the total energy accuracy substantially compared to RPA, especially for smaller-Z atoms. Computational complexity makes post self-consistent-field (post-SCF) evaluation of RPA-type expressions commonplace, so orbital basis origins and properties become important. Sizable differences are found in correlation energies, total atomic energies, and ionization energies for RPA-type functionals evaluated in the post-SCF fashion with orbital sets obtained from different schemes. Reference orbitals from Kohn-Sham calculations with semi-local functionals are more suitable for RPA+SOSEX to generate accurate total energies, but reference orbitals from exact exchange (non-local) yield essentially energetically degenerate open-shell atom ground states. RPA+SOSEX correlation combined with exact exchange calculated from a hybrid reference orbital set (half the exchange calculated from exact-exchange orbitals, the other half of the exchange from orbitals optimized for the Perdew-Burke-Ernzerhof (PBE) exchange functional) gives the best overall performance. Numerical results show that the RPA-like functional with SOSEX correction can be used as a practical implicit current density functional when current effects should be included.

  1. 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

  2. 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…

  3. 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

  4. 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

  5. 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…

  6. 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

  7. 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

  8. Comparing a current-carrying circular wire with polygons of equal perimeter: magnetic field versus magnetic flux

    Science.gov (United States)

    Silva, J. P.; Silvestre, A. J.

    2005-09-01

    We compare the magnetic field at the centre and the self-magnetic flux through a current-carrying circular loop, with those obtained for current-carrying polygons with the same perimeter. As the magnetic field diverges at the position of the wires, we compare the self-fluxes utilizing several regularization procedures. The calculation is best performed utilizing the vector potential, thus highlighting its usefulness in practical applications. Our analysis answers some of the intuition challenges students face when they encounter a related simple textbook example. These results can be applied directly to the determination of mutual inductances in a variety of situations.

  9. 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.

  10. Defect-controlled vortex generation in current-carrying narrow superconducting strips

    Science.gov (United States)

    Vodolazov, D. Yu; Ilin, K.; Merker, M.; Siegel, M.

    2016-02-01

    We experimentally study the effect of a single circular hole on the critical current I c of narrow superconducting strip with width W much smaller than Pearl penetration depth Λ. We found non-monotonous dependence of I c on the location of a hole across the strip and a weak dependence of I c on the radius of a hole in the case of a hole with ξ \\ll R\\ll W (ξ is a superconducting coherence length) which is placed in the center of strip. The observed effects are caused by competition of two mechanisms of destruction of superconductivity—the entrance of vortex via the edge of the strip and the nucleation of the vortex-antivortex pair near the hole. The mechanisms are clearly distinguishable by a difference in dependence of I c on weak magnetic field.

  11. 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.

  12. Nonlinear Resonant Excitation of Fast Sausage Waves in Current-Carrying Coronal Loops

    Science.gov (United States)

    Mikhalyaev, B. B.; Bembitov, D. B.

    2014-11-01

    We consider a model of a coronal loop that is a cylindrical magnetic tube with two surface electric currents. Its principal sausage mode has no cut-off in the long-wavelength limit. For typical coronal conditions, the period of the mode is between one and a few minutes. The sausage mode of flaring loops could cause long-period pulsations observed in microwave and hard X-ray ranges. There are other examples of coronal oscillations: long-period pulsations of active-region quiet loops in the soft X-ray emission are observed. We assume that these can also be caused by sausage waves. The question arises of how the sausage waves are generated in quiet loops. We assume that they can be generated by torsional oscillations. This process can be described in the framework of the nonlinear three-wave interaction formalism. The periods of interacting torsional waves are similar to the periods of torsional oscillations observed in the solar atmosphere. The timescale of the sausage-wave excitation is not much longer than the periods of interacting waves, so that the sausage wave is excited before torsional waves are damped.

  13. Estuarine chinook capacity - Estimating changes in juvenile Chinook rearing area and carrying capacity in estuarine and freshwater habitats of the Puget Sound region

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project has two objectives: 1. Estimate the amount of rearing habitat available to juvenile Chinook salmon currently and historically (i.e., ~1850s) throughout...

  14. 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.

  15. 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

  16. 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...

  17. 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...

  18. 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

  19. 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。

  20. Deformation of the free surface of a conducting fluid in the magnetic field of current-carrying linear conductors

    Science.gov (United States)

    Zubarev, N. M.; Zubareva, O. V.

    2017-06-01

    The magnetic shaping problem is studied for the situation where a cylindrical column of a perfectly conducting fluid is deformed by the magnetic field of a system of linear current-carrying conductors. Equilibrium is achieved due to the balance of capillary and magnetic pressures. Two two-parametric families of exact solutions of the problem are obtained with the help of conformal mapping technique. In accordance with them, the column essentially deforms in the cross section up to its disintegration.

  1. 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

  2. Effect of the magnetic material on AC losses in HTS conductors in AC magnetic field carrying AC transport current

    Science.gov (United States)

    Wan, Xing-Xing; Huang, Chen-Guang; Yong, Hua-Dong; Zhou, You-He

    2015-11-01

    This paper presents an investigation on the AC losses in several typical superconducting composite conductors using the H-formulation model. A single superconducting strip with ferromagnetic substrate or cores and a stack of coated conductors with ferromagnetic substrates are studied. We consider all the coated conductors carrying AC transport currents and simultaneously exposed to perpendicular AC magnetic fields. The influences of the amplitude, frequency, phase difference and ferromagnetic materials on the AC losses are investigated. The results show that the magnetization losses of single strip and stacked strips have similar characteristics. The ferromagnetic substrate can increase the magnetization loss at low magnetic field, and decrease the loss at high magnetic field. The ferromagnetic substrate can obviously increase the transport loss in stacked strips. The trends of total AC losses of single strip and stacked strips are similar when they are carrying current or exposed to a perpendicular magnetic field. The effect of the frequency on the total AC losses of single strip is related to the amplitude of magnetic field. The AC losses decrease with increasing frequency in low magnetic field region while increase in high magnetic field region. As the phase difference changes, there is a periodic variation for the AC losses. Moreover, when the strip is under only the transport current and magnetic field, the ferromagnetic cores will increase the AC losses for large transport current or field.

  3. A statistical study of the THEMIS satellite data for plasma sheet electrons carrying auroral upward field-aligned currents

    Science.gov (United States)

    Lee, S.; Shiokawa, K.; McFadden, J. P.

    2010-12-01

    The magnetospheric electron precipitation along the upward field-aligned currents without the potential difference causes diffuse aurora, and the magnetospheric electrons accelerated by a field-aligned potential difference cause the intense and bright type of aurora, namely discrete aurora. In this study, we are trying to find out when and where the aurora can be caused with or without electron acceleration. We statistically investigate electron density, temperature, thermal current, and conductivity in the plasma sheet using the data from the electrostatic analyzer (ESA) onboard the THEMIS-D satellite launched in 2007. According to Knight (Planet. Space Sci., 1973) and Lyons (JGR, 1980), the thermal current, jth(∝ nT^(1/2) where n is electron density and T is electron temperature in the plasma sheet), represents the upper limit to field aligned current that can be carried by magnetospheric electrons without field-aligned potential difference. The conductivity, K(∝ nT^(-1/2)), represents the efficiency of the upward field-aligned current (j) that the field-aligned potential difference (V) can produce (j=KV). Therefore, estimating jth and K in the plasma sheet is important in understanding the ability of plasma sheet electrons to carry the field-aligned current which is driven by various magnetospheric processes such as flow shear and azimuthal pressure gradient. Similar study was done by Shiokawa et al. (2000) based on the auroral electron data obtained by the DMSP satellites above the auroral oval and the AMPTE/IRM satellite in the near Earth plasma sheet at 10-18 Re on February-June 1985 and March-June 1986 during the solar minimum. The purpose of our study is to examine auroral electrons with pitch angle information inside 12 Re where Shiokawa et al. (2000) did not investigate well. For preliminary result, we found that in the dawn side inner magnetosphere (source of the region 2 current), electrons can make sufficient thermal current without field

  4. 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.

  5. 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

  6. 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

    . From the perspective of estimation and assessment,approaches in evaluating ecological carrying capacity such as net primary production,ecological footprint, sustainable development and the health of ecological system are the primary approaches of measuring, which is the basis of estimating watershed ecological carrying capacity. Currently, the research on the aquatic ecological carrying capacity in the basin is at the initial stage. In the future,it should better reflect the fundamental aim of the harmonious coexistence between human and nature and the dialectical integration of quality and quantity. Meanwhile, the employment of the research approach which integrates material, energy, information, time and space is expected to make the research on the aquatic ecological carrying capacity in the basin more practical.

  7. 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

  8. 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.

  9. Total AC loss of YBCO coated conductor carrying AC transport current in AC transverse magnetic field with various orientations

    Energy Technology Data Exchange (ETDEWEB)

    Amemiya, Naoyuki [Faculty of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501 (Japan); Jiang, Zhenan [Faculty of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501 (Japan); Iijima, Yasuhiro [Materials Research Laboratory, Fujikura Ltd, 1-5-1 Kiba, Koto, Tokyo 135-8512 (Japan); Kakimoto, Kazuomi [Materials Research Laboratory, Fujikura Ltd, 1-5-1 Kiba, Koto, Tokyo 135-8512 (Japan); Saitoh, Takashi [Materials Research Laboratory, Fujikura Ltd, 1-5-1 Kiba, Koto, Tokyo 135-8512 (Japan)

    2004-08-01

    Using an electro-magnetic method, we measured the total AC loss of a YBCO coated conductor carrying an AC transport current in an AC transverse magnetic field with various orientations. We measured the magnetization loss (energy flow from the external magnetic field) and the transport loss (energy flow from the transport current circuit) independently during simultaneous application of an AC transverse magnetic field and AC transport current. Their sum gave us the total AC loss. The transport loss increases with increasing AC transverse magnetic field, and the magnetization loss increases with increasing AC transport current. The AC transverse magnetic field and the AC self magnetic field interact with each other at the conductor edges. This nonlinear interaction is a possible cause of the increase in AC loss. Due to the high aspect ratio of YBCO coated conductors, this increase in AC loss due to the interaction between the AC transverse and AC self magnetic fields is observed even when the transverse magnetic field is nearly parallel to the conductor wide-face. When the total AC losses for various transport currents and various field orientations are plotted against a transverse magnetic field component which is perpendicular to the conductor wide-face, the plots with different field angles but identical transport current all agree quite well with each other. The total AC loss is dominated by the self magnetic field and the perpendicular component of the transverse magnetic field, both of which mostly penetrate from the conductor edges.

  10. Acceleration of electric current-carrying string loop near a Schwarzschild black hole immersed in an asymptotically uniform magnetic field

    CERN Document Server

    Tursunov, Arman; Stuchlík, Zdeněk; Ahmedov, Bobomurat

    2014-01-01

    We study the acceleration of an electric current-carrying and axially-symmetric string loop initially oscillating in the vicinity of a Schwarzschild black hole embedded in an external asymptotically uniform magnetic field. The plane of the string loop is orthogonal to the magnetic field lines and the acceleration of the string loop occurs due to the transmutation effect turning in the deep gravitational field the internal energy of the oscillating strings to the energy of their translational motion along the axis given by the symmetry of the black hole spacetime and the magnetic field. We restrict our attention to the motion of string loop with energy high enough, when it can overcome the gravitational attraction and escape to infinity. We demonstrate that for the current-carrying string loop the transmutation effect is enhanced by the contribution of the interaction between the electric current of the string loop and the external magnetic field and we give conditions that have to be fulfilled for an efficien...

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. LELONG-DEMAILLY NUMBERS IN TERMS OF CAPACITY AND WEAK CONVERGENCE FOR CLOSED POSITIVE CURRENTS

    Institute of Scientific and Technical Information of China (English)

    Fredj ELKHADHRA

    2013-01-01

    In this paper we give a new definition of the Lelong-Demailly number in terms of the CT-capacity, where T is a closed positive current and CT is the capacity associated to T . This derived from some esimate on the growth of the CT-capacity of the sublevel sets of a weighted plurisubharmonic (psh for short) function. These estimates enable us to give another proof of the Demailly’s comparaison theorem as well as a generalization of some results due to Xing concerning the characterization of bounded psh functions. Another problem that we consider here is related to the existence of a psh function v that satisfies the equality CT (K) = RK T ∧(ddcv)p, where K is a compact subset. Finally, we give some conditions on the capacity CT that guarantees the weak convergence uk Tk·uT , for positive closed currents T, Tk and psh functions uk, u.

  17. The quantum-mechanical basis of an extended Landau-Lifshitz-Gilbert equation for a current-carrying ferromagnetic wire.

    Science.gov (United States)

    Edwards, D M; Wessely, O

    2009-04-08

    An extended Landau-Lifshitz-Gilbert (LLG) equation is introduced to describe the dynamics of inhomogeneous magnetization in a current-carrying wire. The coefficients of all the terms in this equation are calculated quantum-mechanically for a simple model which includes impurity scattering. This is done by comparing the energies and lifetimes of a spin wave calculated from the LLG equation and from the explicit model. Two terms are of particular importance since they describe non-adiabatic spin-transfer torque and damping processes which do not rely on spin-orbit coupling. It is shown that these terms may have a significant influence on the velocity of a current-driven domain wall and they become dominant in the case of a narrow wall.

  18. 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...

  19. 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.

  20. 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.

  1. 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.

  2. The Pedersen current carried by electrons: a non-linear response of the ionosphere to magnetospheric forcing

    Directory of Open Access Journals (Sweden)

    S. C. Buchert

    2008-09-01

    Full Text Available Observations by the EISCAT Svalbard radar show that electron temperatures Te in the cusp electrojet reach up to about 4000 K. The heat is tapped and converted from plasma convection in the near Earth space by a Pedersen current that is carried by electrons due to the presence of irregularities and their demagnetising effect. The heat is transfered to the neutral gas by collisions. In order to enhance Te to such high temperatures the maximally possible dissipation at 50% demagnetisation must nearly be reached. The effective Pedersen conductances are found to be enhanced by up to 60% compared to classical values. Conductivities and conductances respond significantly to variations of the electric field strength E, and "Ohm's law" for the ionosphere becomes non-linear for large E.

  3. 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.

  4. 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

  5. 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

  6. Dynamics of current-carrying string loops in the Kerr naked-singularity and black-hole spacetimes

    CERN Document Server

    Kološ, M

    2013-01-01

    Current-carrying string-loop dynamics is studied in the Kerr spacetimes. With attention concentrated to the axisymmetric motion of string loops around symmetry axis of both black-hole (BH) and naked singularity (NS) spacetimes, it is shown that the resulting motion is governed by the presence of an outer tension barrier and an inner angular momentum barrier that are influenced by the BH or NS spin. We classify the string dynamics according to properties of the energy boundary function (effective potential) for the string loop motion. We have found that for NS there exist new types of energy boundary function, namely those with off-equatorial minima. Conversion of the energy of the string oscillations to the energy of the linear translational motion has been studied. Such a transmutation effect is much more efficient in the NS spacetimes because lack of the event horizon. For BH spacetimes efficiency of the transmutation effect is only weakly spin dependent. Transition from regular to chaotic regime of the str...

  7. 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.

  8. Adaptive capacity indicators to assess sustainability of urban water systems - Current application.

    Science.gov (United States)

    Spiller, Marc

    2016-11-01

    Sustainability is commonly assessed along environmental, societal, economic and technological dimensions. A crucial aspect of sustainability is that inter-generational equality must be ensured. This requires that sustainability is attained in the here and now as well as into the future. Therefore, what is perceived as 'sustainable' changes as a function of societal opinion and technological and scientific progress. A concept that describes the ability of systems to change is adaptive capacity. Literature suggests that the ability of systems to adapt is an integral part of sustainable development. This paper demonstrates that indicators measuring adaptive capacity are underrepresented in current urban water sustainability studies. Furthermore, it is discussed under which sustainability dimensions adaptive capacity indicators are lacking and why. Of the >90 indicators analysed, only nine are adaptive capacity indicators, of which six are socio-cultural, two technological, one economical and none environmental. This infrequent use of adaptive capacity indicators in sustainability assessments led to the conclusion that the challenge of dynamic and uncertain urban water systems is, with the exception of the socio-cultural dimension, not yet sufficiently reflected in the application of urban water sustainability indicators. This raises concerns about the progress towards urban water systems that can transform as a response variation and change. Therefore, research should focus on developing methods and indicators that can define, evaluate and quantify adaptive capacity under the economic, environmental and technical dimension of sustainability. Furthermore, it should be evaluated whether sustainability frameworks that focus on the control processes of urban water systems are more suitable for measuring adaptive capacity, than the assessments along environmental, economic, socio-cultural and technological dimensions. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. 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

  10. Link between capacity for current production and syntrophic growth in Geobacter species

    DEFF Research Database (Denmark)

    Rotaru, Amelia-Elena; Woodard, Trevor; Nevin, Kelly;

    2015-01-01

    -culture with Methanosarcina barkeri, which is capable of direct interspecies electron transfer (DIET), but not with Methanospirillium hungatei capable only of H2 or formate transfer. Conductive granular activated carbon (GAC) stimulated metabolism of the G. hydrogenophilus - M. barkeri co-culture, consistent with electron......Electrodes are unnatural electron acceptors, and it is yet unknown how some Geobacter species evolved to use electrodes as terminal electron acceptors. Analysis of different Geobacter species revealed that they varied in their capacity for current production. G. metallireducens and G....... hydrogenophilus generated high current densities (ca. 0.05 mA/cm2), comparable to G. sulfurreducens. G. bremensis, G. chapellei, G. humireducens, and G. uranireducens, produced much lower currents (ca. 0.05 mA/cm2) and G. bemidjiensis was previously found to not produce current. There was no correspondence...

  11. Crystalline-Amorphous Core−Shell Silicon Nanowires for High Capacity and High Current Battery Electrodes

    KAUST Repository

    Cui, Li-Feng

    2009-01-14

    Silicon is an attractive alloy-type anode material for lithium ion batteries because of its highest known capacity (4200 mAh/g). However silicon\\'s large volume change upon lithium insertion and extraction, which causes pulverization and capacity fading, has limited its applications. Designing nanoscale hierarchical structures is a novel approach to address the issues associated with the large volume changes. In this letter, we introduce a core-shell design of silicon nanowires for highpower and long-life lithium battery electrodes. Silicon crystalline- amorphous core-shell nanowires were grown directly on stainless steel current collectors by a simple one-step synthesis. Amorphous Si shells instead of crystalline Si cores can be selected to be electrochemically active due to the difference of their lithiation potentials. Therefore, crystalline Si cores function as a stable mechanical support and an efficient electrical conducting pathway while amorphous shells store Li ions. We demonstrate here that these core-shell nanowires have high charge storage capacity (̃1000 mAh/g, 3 times of carbon) with ̃90% capacity retention over 100 cycles. They also show excellent electrochemical performance at high rate charging and discharging (6.8 A/g, ̃20 times of carbon at 1 h rate). © 2009 American Chemical Society.

  12. Link Between Capacity for Current Production and Syntrophic Growth in Geobacter species

    Directory of Open Access Journals (Sweden)

    Amelia-Elena eRotaru

    2015-07-01

    Full Text Available Electrodes are unnatural electron acceptors, and it is yet unknown how some Geobacter species evolved to use electrodes as terminal electron acceptors. Analysis of different Geobacter species revealed that they varied in their capacity for current production. G. metallireducens and G. hydrogenophilus generated high current densities (ca. 0.05 mA/cm2, comparable to G. sulfurreducens. G. bremensis, G. chapellei, G. humireducens, and G. uranireducens, produced much lower currents (ca. 0.05 mA/cm2 and G. bemidjiensis was previously found to not produce current. There was no correspondence between the effectiveness of current generation and Fe(III oxide reduction rates. Some high-current-density strains (G. metallireducens and G. hydrogenophilus reduced Fe(III-oxides as fast as some low-current-density strains (G. bremensis, G. humireducens, and G. uranireducens whereas other low-current-density strains (G. bemidjiensis and G. chapellei reduced Fe(III oxide as slowly as G. sulfurreducens, a high-current-density strain. However, there was a correspondence between the ability to produce higher currents and the ability to grow syntrophically. G. hydrogenophilius was found to grow in co-culture with Methanosarcina barkeri, which is capable of direct interspecies electron transfer (DIET, but not with Methanospirillium hungatei capable only of H2 or formate transfer. Conductive granular activated carbon (GAC stimulated metabolism of the G. hydrogenophilus - M. barkeri co-culture, consistent with electron exchange via DIET. These findings, coupled with the previous finding that G. metallireducens and G. sulfurreducens are also capable of DIET, suggest that evolution to optimize DIET has fortuitiously conferred the capability for high-density current production to some Geobacter species.

  13. The Current State of Poison Control Centers in Pakistan and the Need for Capacity Building

    Directory of Open Access Journals (Sweden)

    Nadeem Khan

    2014-03-01

    Full Text Available Background: Chemical exposure is a major health problem globally. Poison control centers (PCCs play a leading role both in developed and developing countries in the prevention and control of poisonous chemical exposures. In this study, we aimed to assess the current state of PCCs in Pakistan and highlight capacity building needs in these centers. Methods: A cross-sectional survey of the two registered PCCs was done during August – December 2011. Necessary services of the PCCs were evaluated and the data were recorded on a predesigned checklist. Results: Both PCCs are affiliated to a tertiary care hospital. Clinical services to poisoned patients were available 24 hours a day / 7 days a week. Information on common local products was available to poison center staff. Both centers were involved in undergraduate and post graduate teaching. Telephone poison information service was not available in either of centers. There was a limited capacity for qualitative and analytical toxicology. Common antidotes were available. There were limited surveillance activities to capture toxic risks existing in the community and also a deficiency was observed in chemical disaster planning. Conclusion: PCCs in Pakistan need capacity building for specialized training in toxicology, toxicovigilance, chemical disaster planning, analytical laboratory tests and telephone service for consultation in poisoning cases.   How to cite this article: Khan NU, Mir MU, Khan UR, Khan AR, Ara J, Raja K, et al. The Current State of Poison Control Centers in Pakistan and the Need for Capacity Building. Asia Pac J Med Toxicol 2014;3:31-5.

  14. 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.

  15. 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.

  16. 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

  17. The current capacity for training in public health nutrition in West Africa.

    Science.gov (United States)

    Pepping, Fré

    2010-01-01

    This article is based on a paper prepared for the Workshop on Establishing a Regional Institute for Public Health Nutrition Research and Training in West Africa, convened in Dakar, Senegal, 26-28 March, 2009. Information was gathered mainly prior to this workshop; several responses, however, came in after the workshop and these have been included in the current paper. In completion of the article use was made of the views and opinions as expressed during this workshop. Objectives were to provide background information on academic programmes (undergraduate and graduate) and research institutions with a focus on human nutrition in West Africa, to describe the importance of foreign nutrition training programmes for West African students and to detail existing nutrition training activities currently in the region. Data were obtained from a survey of 15 UNICEF country offices in the West African region, previously published reports, United Nations University/International Union of Nutrition Sciences capacity development activities 1996-2009, personal communications and websites of relevant African institutions. Results indicate that West African nutrition academic programmes and research institutes do not adequately meet the demand for nutritionists and technical services in the region. Exceptions seem to be Benin, Ghana and Nigeria. Diploma courses and other short courses have been an important means of attracting people from a variety of disciplines to nutrition. A well-equipped regional institute could directly and indirectly bolster nutrition capacity in the region. To meet the regional nutrition research and training needs in West Africa, it is not necessary to make a choice between creating a new regional institution vs. expanding existing national institutions. Based on solid capacity development principles, both options need action.

  18. The Effects of Transcranial Direct Current Stimulation (tDCS on Multitasking Throughput Capacity

    Directory of Open Access Journals (Sweden)

    Justin Nelson

    2016-11-01

    Full Text Available Background: Multitasking has become an integral attribute associated with military operations within the past several decades. As the amount of information that needs to be processed during these high level multitasking environments exceeds the human operators’ capabilities, the information throughput capacity reaches an asymptotic limit. At this point, the human operator can no longer effectively process and respond to the incoming information resulting in a plateau or decline in performance. The objective of the study was to evaluate the efficacy of a non-invasive brain stimulation technique known as transcranial direct current stimulation (tDCS applied to a scalp location over the left dorsolateral prefrontal cortex (lDLPFC to improve information processing capabilities during a multitasking environment. Methods: The study consisted of 20 participants from Wright-Patterson Air Force Base (16 male and 4 female with an average age of 31.1 (SD = 4.5. Participants were randomly assigned into two groups, each consisting of eight males and two females. Group one received 2mA of anodal tDCS and group two received sham tDCS over the lDLPFC on their testing day. Results: The findings indicate that anodal tDCS significantly improves the participants’ information processing capability resulting in improved performance compared to sham tDCS. For example, the multitasking throughput capacity for the sham tDCS group plateaued near 1.0 bits/s at the higher baud input (2.0 bits/s whereas the anodal tDCS group plateaued near 1.3 bits/s. Conclusion: The findings provided new evidence that tDCS has the ability to augment and enhance multitasking capability in a human operator. Future research should be conducted to determine the longevity of the enhancement of transcranial direct current stimulation on multitasking performance, which has yet to be accomplished.

  19. Strongly Enhanced Current-Carrying Performance in MgB2 Tape Conductors by Novel C60 Doping

    OpenAIRE

    Zhang, Xianping; Ma, Yanwei; Gao, Zhaoshun; Wang, Dongliang; Wang, Lei; Liu, Wei; Wang, Chunru

    2008-01-01

    MgB2 is a promising superconductor for important large-scale applications for both high field magnets and cryocooler-cooled magnet operated at temperatures around 20 K. In this work, by utilizing C60 as a viable alternative dopant, we demonstrate a simple and industrially scaleable rout that yields a 10-15-fold improvement in the in-high-field current densities of MgB2 tape conductors. For example, a Jc value higher than 4x10^4 A/cm^2 (4.2 K, 10 T), which exceeds that for NbTi superconductor,...

  20. A comprehensive mapping of the current capacity for human nutrition training in Cameroon

    Directory of Open Access Journals (Sweden)

    Roger Sodjinou

    2016-01-01

    Full Text Available Background: There is consensus among stakeholders in Cameroon on the need to develop and strengthen human resource capacity for nutrition. This study was conducted to provide a comprehensive mapping of the current capacity for tertiary-level human nutrition training in Cameroon. Design: Participating institutions included university-level institutions offering dedicated nutrition degree programs or other programs in which nutrition courses were taught. A semi-structured questionnaire administered during in-person interviews was used to collect data on existing programs and content of training curricula. Nutrition curricula were reviewed against the following criteria: intended objectives, coverage of nutrition topics, and teaching methods. Results: In total, five nutrition degree programs (four undergraduate programs and one master's program were identified. Three additional programs were about to be launched at the time of data collection. We did not find any doctorate degree programs in nutrition. All the undergraduate programs only had little focus on public health nutrition whereas the master's program in our sample offered a good coverage of all dimensions of human nutrition including basic and applied nutrition. The predominant teaching method was didactic lecture in all the programs. We did not find any formal documentation outlining the competencies that students were expected to gain upon completion of these programs. Nutrition courses in agricultural and health schools were limited in terms of contact hours and scope. Public health nutrition was not covered in any of the health professional schools surveyed. We found no institution offering in-service nutrition training at the time of the study. Conclusions: Based on our findings, we recommend that nutrition training programs in Cameroon be redesigned to make them more responsive to the public health needs of the country.

  1. An empirical model for salt removal percentage in water under the effect of different current intensities of current carrying coil at different flow rates

    Directory of Open Access Journals (Sweden)

    Rameen S. AbdelHady

    2011-10-01

    Full Text Available The magnetic treatment of hard water is an alternative, simple approach by which the hard water that needs to be treated flows through a magnetic field. This field is created by inducing current in a coil wrapped around a pipe. Consequently some of its properties, such as total dissolved salts (TDS, conductivity (Ec and PH change. The primary purpose of hard water treatment is to decrease TDS in the incoming liquid stream. Using performance data from the application of different magnetic field densities on the different flow levels of water, empirical mathematical models were developed relating the salt removal percentage (SRP to operating flow rate and current of the coil. The obtained experimental results showed that the SRP increased with increasing the current at low flow rates (up to 0.75 ml/s.

  2. 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

  3. 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

  4. The direct relationship between output power and current carrying capability of rotor bars in HTS induction/synchronous motor with the use of DI-BSCCO tapes

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, T; Nagao, K; Nishimura, T; Ogama, Y; Kawamoto, M [Department of Electrical Engineering, Graduate School of Engineering, Kyoto University, 1 Kyoto-Daigaku Katsura, Nishikyo-Ku, Kyoto 615-8510 (Japan); Okazaki, T; Ayai, N; Oyama, H [Electric Power and Energy Research Laboratories, Sumitomo Electric Industries, Ltd, 1-1-3, Shimaya, Konohaya-Ku, Osaka 554-0024 (Japan)], E-mail: tk_naka@kuee.kyoto-u.ac.jp

    2008-08-15

    We report on the direct relationship between output power and the current carrying capability of a squirrel-cage HTS induction/synchronous motor based on experiment. The secondary windings are fabricated by use of so-called DI-BSCCO tapes, and the conventional (normal conducting) stator, three-phase and four-pole, is utilized. The tests are carried out in liquid nitrogen for two kinds of HTS windings, in which the number of HTS rotor bars is varied. It is directly shown that the output power is proportional to the rotor bars' critical current at 77 K. In other words, the torque can be enlarged by increasing the critical current of the HTS rotor bars.

  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. Current Trends of High capacity Optical Interconnection Data Link in High Performance Optical Communication Systems

    Directory of Open Access Journals (Sweden)

    Ahmed Nabih Zaki Rashed

    2013-02-01

    Full Text Available Optical technologies are ubiquitous in telecommunications networks and systems, providing multiple wavelength channels of transport at 2.5 Gbit/sec to 40 Gbit/sec data rates over single fiber optic cables. Market pressures continue to drive the number of wavelength channels per fiber and the data rate per channel. This trend will continue for many years to come as electronic commerce grows and enterprises demand higher and reliable bandwidth over long distances. Electronic commerce, in turn, is driving the growth curves for single processor and multiprocessor performance in data base transaction and Web based servers. Ironically, the insatiable taste for enterprise network bandwidth, which has driven up the volume and pushed down the price of optical components for telecommunications, is simultaneously stressing computer system bandwidth increasing the need for new interconnection schemes and providing for the first time commercial opportunities for optical components in computer systems. The evolution of integrated circuit technology is causing system designs to move towards communication based architectures. We have presented the current tends of high performance system capacity of optical interconnection data transmission link in high performance optical communication and computing systems over wide range of the affecting parameters.

  8. 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.

  9. 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.

  10. 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...

  11. 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 ocean is an important strategic resource in coastal countries and regions. The coastal area has the largest population, the biggest population density, and is the most developed area in China as in other coastal countries. Bohai Sea Ring Area and the Changjiang River Delta, Zhujiang River Delta are the three economic growth poles in China coastal area. With the great growth of economy and society, the contradiction between supply and demand of land resources has become increasingly prominent, marine resources have been predato-ry exploited, marine environment has been seriously polluted. Carrying capacity is an important study on coor-dinating development of resources, environment, and economy. Marine carrying capacity is generally be de-fined as the capacity or limit of the harmonious development of population, environment, and socio-economic that the ocean can carry in a certain period without damaging the sustainable development of marine resource and environment, and ensuring a certain living standard. Marine carrying capacity assessment is of great signif-icance for the sustainable exploitation of marine resources, the environment protection and the coordinated de-velopment of regional economy and society in coastal areas. In this context, evaluation on carrying capacity of Bohai Sea Ring Area is of great significance to the sustainable development of the Bohai Sea economic circle. Since marine resources system has mobility, renewability and other characteristics, marine carrying capacity has openness, dynamics and complexity, it is difficult to accurately quantify the population, environment and socio-economic development or limits that marine carrying capacity can support. But by constructing indicator system, we can measure the dynamic change trend and relative marine carrying capacity then guide the devel-opment of marine economic activities. The fuzzy comprehensive evaluation method is based on the fuzzy math-ematics principle, to analyze and evaluate

  12. New method evaluating currents keeping the voltage constant for fast and highly resolved measurement of Arrhenius relation and capacity fade

    Science.gov (United States)

    Lewerenz, Meinert; Käbitz, Stefan; Knips, Marcus; Münnix, Jens; Schmalstieg, Johannes; Warnecke, Alexander; Sauer, Dirk Uwe

    2017-06-01

    The evaluation of floating currents is a powerful method to characterize capacity fade induced by calendaric aging and enables a highly resolved representation of the Arrhenius relation. The test arrangement is simple and could constitute a cheap alternative to state-of-the-art calendaric aging tests including check-up tests. Therefore the currents to maintain a constant voltage are evaluated. This method is validated by analyzing nine cylindrical 8 Ah LiFePO4|Graphite battery cells during calendaric aging at 25 °C, 40 °C and 60 °C at 3.6 V (100% SOC). The 3.6 V are kept by applying constant voltage while the floating currents are logged. The floating currents correlate with the rate of capacity loss measured during capacity tests. The floating currents reveal to be rather constant at 25 °C, linearly increasing at 40 °C and decreasing from a higher level at 60 °C. Additional tests with three test cells, with the temperature rising from 40 to 60 °C in steps of 5 K, exhibit non-constant currents starting from 50 °C on with high variations amongst the tested cells. Once stored above 50 °C, the cells exhibit increased floating currents compared to the measurement at the same temperature before exceeding 50 °C.

  13. A refined integro-surface energy-based model for vibration of magnetically actuated double-nanowire-systems carrying electric current

    Science.gov (United States)

    Kiani, Keivan

    2017-02-01

    A novel surface energy-based model is developed to examine more precisely vibrations of current-carrying double-nanowire-systems immersed in a longitudinal magnetic field. Using Biot-Savart and Lorentz laws, a more refined version of interwire interactional magnetic forces is presented. By employing Rayleigh beam theory, the equations of motion are derived. In fact, these are coupled integro-differential equations which are more accurate with respect to those of the previously developed models. For simply supported and clamped nanosystems, governing equations are analyzed via assumed mode method. The effects of interwire distance, slenderness ratio, electric current, magnetic field strength, and surface effect on the fundamental frequency are addressed carefully. The obtained results display the importance of exploiting the refined model for vibration analysis of nanosystems with low interwire distance, high electric current, and high magnetic field strength.

  14. 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。

  15. 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

  16. 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.

  17. 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.

  18. 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

  19. Forced vibrations of a current-carrying nanowire in a longitudinal magnetic field accounting for both surface energy and size effects

    Science.gov (United States)

    Kiani, Keivan

    2014-09-01

    Forced vibrations of current-carrying nanowires in the presence of a longitudinal magnetic field are of interest. By considering the surface energy and size effects, the coupled equations of motion describing transverse motions of the nanostructure are derived. By employing Galerkin and Newmark-β approaches, the deflections of the nanowire subjected to transverse dynamic loads are evaluated. The effects of the magnetic field, electric current, pre-tension force, frequency of the applied load, surface and size effects on the maximum transverse displacements are discussed. The obtained results display that for the frequency of the applied load lower than the nanowire's fundamental frequency, by increasing the magnetic field or electric current, the maximum transverse displacements would increase. However, for exciting frequencies greater than that of the nanowire, maximum transverse displacements would increase or decrease with the magnetic field strength or electric current. Additionally, the pre-tension force results in decreasing of the maximum transverse displacements. Such a reduction is more apparent for higher values of the magnetic field strength and electric current. The present study would be useful in the design of the micro- and nano-electro-mechanical systems expected to be one of the most wanted technologies in the near future.

  20. 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。

  1. A Deep Analysis of the Magnetic Field Produced by a Current-Carrying Straight Solenoid%长直螺线管磁场的深入分析

    Institute of Scientific and Technical Information of China (English)

    曾晓英; 杨昌虎; 杨昶

    2001-01-01

    将长直螺线管磁场看作直线电流磁场和圆线圈电流磁场迭加。在此基础上,对螺线管磁场进行了深入分析和精确计算,给出了一般情形下近似描述长直螺线管磁场需满足的结构条件。%Decomposing the magnetic filed of a current-carrying strainght solenoid into that of straight current and that of circular curr ent, deep analysis and exact calculation of the field are proposed, and the approximation conditions have been derived for the description of the magnetic field of a straight solenoid in simplified case.

  2. 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。

  3. 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.

  4. Agricultural net primary production in relation to that liberated by the extinction of Pleistocene mega-herbivores: an estimate of agricultural carrying capacity?

    Energy Technology Data Exchange (ETDEWEB)

    Doughty, Christopher E; Field, Christopher B, E-mail: chris.doughty@ouce.ox.ac.uk, E-mail: cfield@ciw.edu [Department of Global Ecology, Carnegie Institution, Stanford, CA 94305 (United States)

    2010-10-15

    Mega-fauna (defined as animals > 44 kg) experienced a global extinction with 97 of 150 genera going extinct by {approx} 10 000 years ago. We estimate the net primary production (NPP) that was liberated following the global extinction of these mega-herbivores. We then explore how humans, through agriculture, gradually appropriated this liberated NPP, with specific calculations for 800, 1850, and 2000 AD. By 1850, most of the liberated NPP had been appropriated by people, but NPP was still available in the Western US, South America and Australia. NPP liberated following the extinction of the mega-herbivores was {approx} 2.5% ({approx}1.4 (between 1.2 and 1.6) Pg yr{sup -1} of 56 Pg C yr{sup -1}; Pg: petagrams) of global terrestrial NPP. Liberated NPP peaked during the onset of agriculture and was sufficient for sustaining human agriculture until {approx} 320 (250-500) years ago. Humans currently use {approx} 6 times more NPP than was utilized by the extinct Pleistocene mega-herbivores.

  5. 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

  6. RANDOM VIBRATION OF A CURRENT CARRYING CIRCULAR PLATE IN MAGNETIC FIELD%载流圆板的磁弹性随机振动

    Institute of Scientific and Technical Information of China (English)

    王平; 李晓靓; 白象忠

    2012-01-01

    The magnetic-elastic random vibration problem of a current-carrying circular plate in a magnetic field is studied. Based on the magneto-elastic theory and the random vibration theory of a continue system with distributed parameters, the magneto-elastic random vibration equation of a current carrying circular plate in a magnetic field was derived. The stochastic response analysis of the circular plate in a magnetic field was finished. The auto-correlation function, power spectral density function and the mean function of the random displacement response of the circular plate in a magnetic field were obtained. In a specific example, the power spectral density function of the displacement response of the circular plate with stationary random current was calculated.%分析载流圆板在磁场中的磁弹性随机振动问题.根据薄板、薄壳体的磁弹性运动方程和连续体的随机振动理论,导出在磁场环境中圆板的磁弹性随机振动方程.对磁场中的载流圆板进行随机响应分析,得到圆板位移响应的自相关函数、功率谱密度函数及均值函数等数字特征.通过具体算例,对处于外加磁场中通入平稳随机电流的导电圆板,计算其位移响应的功率谱密度函数.

  7. 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

  8. 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.

  9. 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.

  10. Mathematical Modeling of Self- Purification Capacity of Surface Currents. Study Case: Portoviejo River, Ecuador

    Directory of Open Access Journals (Sweden)

    Luis Santiago Quiroz Fernández

    2016-11-01

    Full Text Available It is proposed a phenomenological model to describe the behavior of oxygen concentration with respect to distance from wastewater loading into the river. It taken into account processes associated with con-taminants biodegradation and oxygen transfer through interface air-water. The model was used to study contamination of Portoviejo River, Manabí, Ecuador. Experimental results were adjusted to an approx-imate solution of the obtained no-linear equations system, and it was possible to estimate parameters which are related with the capacity of self-purification of two river zones. 

  11. 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。

  12. 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。

  13. A systematic assessment of the current capacity to act in nutrition in West Africa: cross-country similarities and differences

    Directory of Open Access Journals (Sweden)

    Roger Sodjinou

    2014-07-01

    Full Text Available Background: Although it is widely accepted that lack of capacity is one of the barriers to scaling up nutrition in West Africa, there is a paucity of information about what capacities exist and the capacities that need to be developed to accelerate progress toward improved nutrition outcomes in the region. Objective: To systematically assess the current capacity to act in nutrition in the West Africa region and explore cross-country similarities and differences. Design: Data were collected from 13 West African countries through interviews with government officials, key development partners, tertiary-level training institutions, and health professional schools. The assessment was based on a conceptual framework of four interdependent levels (tools; skills; staff and infrastructure; and structures, systems and roles. In each of the surveyed countries, we assessed capacity assets and gaps at individual, organizational, and systemic levels. Results: Important similarities and differences in capacity assets and gaps emerged across all the surveyed countries. There was strong momentum to improve nutrition in nearly all the surveyed countries. Most of the countries had a set of policies on nutrition in place and had set up multisectoral, multi-stakeholder platforms to coordinate nutrition activities, although much remained to be done to improve the effectiveness of these platforms. Many initiatives aimed to reduce undernutrition were ongoing in the region, but there did not seem to be clear coordination between them. Insufficient financial resources to implement nutrition activities were a major problem in all countries. The bulk of financial allocations for nutrition was provided by development partners, even though some countries, such as Niger, Nigeria, and Senegal, had a national budget line for nutrition. Sporadic stock-outs of nutrition supplies were reported in most of the countries as a result of a weak logistic and supply chain system. They

  14. Evolution of the Coronal Magnetic Configurations Including a Current-Carrying Flux Rope in Response to the Change in the Background Field

    CERN Document Server

    Wang, Hong-Juan; Gong, Jian-Cun; Lin, Jun

    2014-01-01

    We investigate equilibrium height of the flux rope, and its internal equilibrium in a realistic plasma environment by carrying out numerical simulations of the evolution of systems including a current-carrying flux rope. We find that the equilibrium height of the flux rope is approximately a power-law function of the relative strength of the background field. Our simulations indicate that the flux rope can escape more easily from a weaker background field. This further confirms the catastrophe in the magnetic configuration of interest can be triggered by decrease of strength of the background field. Our results show that it takes some time to reach internal equilibrium depending on the initial state of the flux rope. The plasma flow inside the flux rope due to the adjustment for the internal equilibrium of the flux rope remains small and does not last very long when the initial state of the flux rope commences from the stable branch of the theoretical equilibrium curve. This work also confirms the influence o...

  15. 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…

  16. 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…

  17. 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...

  18. Current-carrying element based on second-generation high-temperature superconductor for the magnet system of a fusion neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Novikov, M. S., E-mail: mihailnovikov@yandex.ru; Ivanov, D. P., E-mail: Ivanov-DP@nrcki.ru, E-mail: denis.ivanov30@mail.ru; Novikov, S. I., E-mail: novikov-si@nrcki.ru; Shuvaev, S. A., E-mail: ser-shuvaev@yandex.ru, E-mail: sergey.shuvaev@phystech.edu [National Research Center Kurchatov Institute (Russian Federation)

    2015-12-15

    Application of current-carrying elements (CCEs) made of second-generation high-temperature superconductor (2G HTS) in magnet systems of a fusion neutron source (FNS) and other fusion devices will allow their magnetic field and thermodynamic stability to be increased substantially in comparison with those of low-temperature superconductor (LTS) magnets. For a toroidal magnet of the FNS, a design of a helical (partially transposed) CCE made of 2G HTS is under development with forced-flow cooling by helium gas, a current of 20–30 kA, an operating temperature of 10–20 K, and a magnetic field on the winding of 12–15 T (prospectively ∼20 T). Short-sized samples of the helical flexible heavy-current CCE are being fabricated and investigated; a pilot-line unit for production of long-sized CCE pieces is under construction. The applied fabrication technique allows the CCE to be produced which combines a high operating current, thermal and mechanical stability, manufacturability, and low losses in the alternating modes. The possibility of fabricating the CCE with the outer dimensions and values of the operating parameter required for the FNS (and with a significant margin) using already available serial 2G HTS tapes is substantiated. The maximum field of toroidal magnets with CCEs made of 2G HTS will be limited only by mechanical properties of the magnet’s casing and structure, while the thermal stability will be approximately two orders of magnitude higher than that of toroidal magnets with LTS-based CCEs. The helical CCE made of 2G HTS is very promising for fusion and hybrid electric power plants, and its design and technologies of production, as well as the prototype coils made of it for the FNS and other tokamaks, are worth developing now.

  19. 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

  20. 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。

  1. Improved cardiac function and exercise capacity following correction of pectus excavatum: a review of current literature.

    Science.gov (United States)

    Maagaard, Marie; Heiberg, Johan

    2016-09-01

    Patients with pectus excavatum (PE) often describe improvements in exercise stamina following corrective surgery. Studies have investigated the surgical effect on physiological parameters; still, no consensus has yet been reached. Therefore, the aim of this literature review was to describe the cardiac outcome after surgical correction, both at rest and during exercise. In February 2016, a detailed search of the databases PubMed, Medline, and EMBASE was performed. We assessed clinical studies that described cardiac outcomes both before and after surgical correction of PE. We only included studies reporting either pre-defined echocardiographic or exercise test parameters. No exclusion criteria or statistical analyses were applied. Twenty-one full-text articles, published between 1972 and 2016, were selected, with cohort-ranges of 3-168 patients, mean age-ranges of 5-33 years, and mean follow-up-ranges from immediately to 4 years after surgery. Twelve studies described resting cardiac parameters. Four studies measured cardiac output, where one described 36% immediate increase after surgery, one reported 15% increase after Nuss-bar removal and two found no difference. Three studies demonstrated improvement in mean stroke volume ranges of 22-34% and two studies found no difference. Fifteen studies investigated exercise capacity, with 11 considering peak O2 pr. kg, where five studies demonstrated improvements with the mean ranging from 8% to 15% after surgery, five studies demonstrated no difference, and one saw a decrease of 19% 3 months after Nuss-bar implantation. A measurable increase in exercise capacity exists following surgery, which may be caused by multiple factors. This may be owed to the relief of compressed cardiac chambers with the increased anterior-posterior thoracic dimensions, which could facilitate an improved filling of the heart. With these results, the positive physiological impact of the surgery is emphasized and the potential gain in cardiac

  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. Analysis of the Capacity Potential of Current Day and Novel Configurations for New York's John F. Kennedy Airport

    Science.gov (United States)

    Glaab, Patricia; Tamburro, Ralph; Lee, Paul

    2016-01-01

    In 2015, a series of systems analysis studies were conducted on John F. Kennedy Airport in New York (NY) in a collaborative effort between NASA and the Port Authority of New York and New Jersey (PANYNJ). This work was performed to build a deeper understanding of NY airspace and operations to determine the improvements possible through operational changes with tools currently available, and where new technology is required for additional improvement. The analysis was conducted using tool-based mathematical analyses, video inspection and evaluation using recorded arrival/departure/surface traffic captured by the Aerobahn tool (used by Kennedy Airport for surface metering), and aural data archives available publically through the web to inform the video segments. A discussion of impacts of trajectory and operational choices on capacity is presented, including runway configuration and usage (parallel, converging, crossing, shared, independent, staggered), arrival and departure route characteristics (fix sharing, merges, splits), and how compression of traffic is staged. The authorization in March of 2015 for New York to use reduced spacing under the Federal Aviation Administration (FAA) Wake Turbulence Recategorization (RECAT) also offers significant capacity benefit for New York airports when fully transitioned to the new spacing requirements, and the impact of these changes for New York is discussed. Arrival and departure capacity results are presented for each of the current day Kennedy Airport configurations. While the tools allow many variations of user-selected conditions, the analysis for these studies used arrival-priority, no-winds, additional safety buffer of 5% to the required minimum spacing, and a mix of traffic typical for Kennedy. Two additional "novel" configurations were evaluated. These configurations are of interest to Port Authority and to their airline customers, and are believed to offer near-term capacity benefit with minimal operational and

  5. Electron transfer capacity dependence of quinone-mediated Fe(III) reduction and current generation by Klebsiella pneumoniae L17.

    Science.gov (United States)

    Li, Xiaomin; Liu, Liang; Liu, Tongxu; Yuan, Tian; Zhang, Wei; Li, Fangbai; Zhou, Shungui; Li, Yongtao

    2013-06-01

    Quinone groups in exogenous electron shuttles can accelerate extracellular electron transfer (EET) from bacteria to insoluble terminal electron acceptors, such as Fe(III) oxides and electrodes, which are important in biogeochemical redox processes and microbial electricity generation. However, the relationship between quinone-mediated EET performance and electron-shuttling properties of the quinones remains incompletely characterized. This study investigates the effects of a series of synthetic quinones (SQs) on goethite reduction and current generation by a fermenting bacterium Klebsiella pneumoniae L17. In addition, the voltammetric behavior and electron transfer capacities (ETCs) of SQ, including electron accepting (EAC) and donating (EDC) capacities, is also examined using electrochemical methods. The results showed that SQ can significantly increase both the Fe(III) reduction rates and current outputs of L17. Each tested SQ reversibly accepted and donated electrons as indicated by the cyclic voltammograms. The EAC and EDC results showed that Carmine and Alizarin had low relative capacities of electron transfer, whereas 9,10-anthraquinone-2,6-disulfonic acid (AQDS), 2-hydroxy-1,4-naphthoquinone (2-HNQ), and 5-hydroxy-1,4-naphthoquinone (5-HNQ) showed stronger relative ETC, and 9,10-anthraquinone-2-carboxylic acid (AQC) and 9,10-anthraquinone-2-sulfonic acid (AQS) had high relative ETC. Enhancement of microbial goethite reduction kinetics and current outputs by SQ had a good linear relationship with their ETC, indicating that the effectiveness of quinone-mediated EET may be strongly dependent on the ETC of the quinones. Therefore, the presence of quinone compounds and fermenting microorganisms may increase the diversity of microbial populations that contribute to element transformation in natural environments. Moreover, ETC determination of different SQ would help to evaluate their performance for microbial EET under anoxic conditions. Copyright © 2013 Elsevier

  6. 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.

  7. 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

  8. 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

  9. Financing and current capacity for REDD+ readiness and monitoring, measurement, reporting and verification in the Congo Basin

    Science.gov (United States)

    Maniatis, Danae; Gaugris, Jérôme; Mollicone, Danilo; Scriven, Joel; Corblin, Alexis; Ndikumagenge, Cleto; Aquino, André; Crete, Philippe; Sanz-Sanchez, Maria-José

    2013-01-01

    This paper provides the first critical analysis of the financing and current capacity for REDD+ readiness in the Congo Basin, with a particular focus on the REDD+ component of national forest monitoring and measurement, reporting and verification (M&MRV). We focus on three areas of analysis: (i) general financing for REDD+ readiness especially M&MRV; (ii) capacity and information for REDD+ implementation and M&MRV; (iii) prospects and challenges for REDD+ and M&MRV readiness in terms of financing and capacity. For the first area of analysis, a REDD+ and M&MRV readiness financing database was created based on the information from the REDD+ voluntary database and Internet searches. For the second area of analysis, a qualitative approach to data collection was adopted (semi-structured interviews with key stakeholders, surveys and observations). All 10 countries were visited between 2010 and 2012. We find that: (i) a significant amount of REDD+ financing flows into the Congo Basin (±US$550 million or almost half of the REDD+ financing for the African continent); (ii) across countries, there is an important disequilibrium in terms of REDD+ and M&MRV readiness financing, political engagement, comprehension and capacity, which also appears to be a key barrier to countries receiving equal resources; (iii) most financing appears to go to smaller scale (subnational) REDD+ projects; (iv) four distinct country groups in terms of REDD+ readiness and M&MRV status are identified; and (v) the Congo Basin has a distinct opportunity to have a specific REDD+ financing window for large-scale and more targeted national REDD+ programmes through a specific fund for the region. PMID:23878337

  10. Financing and current capacity for REDD+ readiness and monitoring, measurement, reporting and verification in the Congo Basin.

    Science.gov (United States)

    Maniatis, Danae; Gaugris, Jérôme; Mollicone, Danilo; Scriven, Joel; Corblin, Alexis; Ndikumagenge, Cleto; Aquino, André; Crete, Philippe; Sanz-Sanchez, Maria-José

    2013-01-01

    This paper provides the first critical analysis of the financing and current capacity for REDD+ readiness in the Congo Basin, with a particular focus on the REDD+ component of national forest monitoring and measurement, reporting and verification (M&MRV). We focus on three areas of analysis: (i) general financing for REDD+ readiness especially M&MRV; (ii) capacity and information for REDD+ implementation and M&MRV; (iii) prospects and challenges for REDD+ and M&MRV readiness in terms of financing and capacity. For the first area of analysis, a REDD+ and M&MRV readiness financing database was created based on the information from the REDD+ voluntary database and Internet searches. For the second area of analysis, a qualitative approach to data collection was adopted (semi-structured interviews with key stakeholders, surveys and observations). All 10 countries were visited between 2010 and 2012. We find that: (i) a significant amount of REDD+ financing flows into the Congo Basin (±US$550 million or almost half of the REDD+ financing for the African continent); (ii) across countries, there is an important disequilibrium in terms of REDD+ and M&MRV readiness financing, political engagement, comprehension and capacity, which also appears to be a key barrier to countries receiving equal resources; (iii) most financing appears to go to smaller scale (subnational) REDD+ projects; (iv) four distinct country groups in terms of REDD+ readiness and M&MRV status are identified; and (v) the Congo Basin has a distinct opportunity to have a specific REDD+ financing window for large-scale and more targeted national REDD+ programmes through a specific fund for the region.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. Evaluation capacity development in Africa: Current landscape of international partners’ initiatives, lessons learned and the way forward

    Directory of Open Access Journals (Sweden)

    Michele Tarsilla

    2014-12-01

    Full Text Available Despite the copious resources allocated by international development partners to enhance African countries’ capacity to evaluate the performance and impact of development programmes and policies, most evaluation capacity building (ECB efforts have not yielded the expected results. Time and energy have been focused on the measurement of short-term effects whilst long-term results have largely remained elusive. As a result, a variety of actors across the continent are calling for more innovative strategies. In particular, more efforts are currently being made to revitalise the evaluation function in international development at the global level and to enhance a shift from short-term training to more contextually relevant, systemic learning, equity and sustainability efforts. This article aims to provide a critical overview of ECB initiatives undertaken by international development partners in Africa over five years (2009–2014 that worked well and investigate how they could be improved. The common issues stress the need for harmonisation and collaboration between international partners and African institutions and more effective collaboration with in country institutions and organisations committed to evaluation capacity development (ECD. The analysis in this article is timely and relevant for both the strengthening of socalled made-in Africa evaluation methods and approaches and the roll-out of systemic and organic ECD strategies. The debate spurred by this article is likely to contribute to the current global debate on what strategies ought to be taken as part of the post-2015 agenda. This inturn will spur the debate on ECD to increase in importance and undoubtedly in intensity.

  16. 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

  17. 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.

  18. 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

  19. 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

  20. 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

  1. 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

  2. Selection of a variant of Geobacter sulfurreducens with enhanced capacity for current production in microbial fuel cells.

    Science.gov (United States)

    Yi, Hana; Nevin, Kelly P; Kim, Byoung-Chan; Franks, Ashely E; Klimes, Anna; Tender, Leonard M; Lovley, Derek R

    2009-08-15

    Geobacter sulfurreducens produces current densities in microbial fuel cells that are among the highest known for pure cultures. The possibility of adapting this organism to produce even higher current densities was evaluated. A system in which a graphite anode was poised at -400 mV (versus Ag/AgCl) was inoculated with the wild-type strain of G. sulfurreducens, strain DL-1. An isolate, designated strain KN400, was recovered from the biofilm after 5 months of growth on the electrode. KN400 was much more effective in current production than strain DL-1. This was apparent with anodes poised at -400 mV, as well as in systems run in true fuel cell mode. KN400 had current (7.6A/m(2)) and power (3.9 W/m(2)) densities that respectively were substantially higher than those of DL1 (1.4A/m(2) and 0.5 W/m(2)). On a per cell basis KN400 was more effective in current production than DL1, requiring thinner biofilms to make equivalent current. The enhanced capacity for current production in KN400 was associated with a greater abundance of electrically conductive microbial nanowires than DL1 and lower internal resistance (0.015 versus 0.130 Omega/m(2)) and mass transfer limitation in KN400 fuel cells. KN400 produced flagella, whereas DL1 does not. Surprisingly, KN400 had much less outer-surface c-type cytochromes than DL1. KN400 also had a greater propensity to form biofilms on glass or graphite than DL1, even when growing with the soluble electron acceptor, fumarate. These results demonstrate that it is possible to enhance the ability of microorganisms to electrochemically interact with electrodes with the appropriate selective pressure and that improved current production is associated with clear differences in the properties of the outer surface of the cell that may provide insights into the mechanisms for microbe-electrode interactions.

  3. 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.

  4. 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。

  5. 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。

  6. 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

    in 2006 and human disturbance threshold(5.96%) of Haixi Zone;the human disturbance index of all sub-zones of Haixi Zone was lower than its human disturbance threshold.Current human disturbance carried by ecosystem in Haixi Zone was relative light;human activities and key industrial development haven't threatened regional ecosystem structure,service and its health status.According to the production rate of construction land in Haixi Zone,Haixi Zone and all sub-zones could sustain the present development of key industry,but Haixi Zone and most sub-zones wouldn't sustain the medium and long term development of their key industry.As the production rate of construction land in Haixi Zone rises to 75% of the production rate of construction land in Shanghai city in 2007,Haixi Zone and most sub-zones would sustain the medium and long term development of their key industry.Therefore,the production rate of construction land is the key factor that influences ecological carrying capacity,the sustain development of key industry and ecological security of Haixi Zone.Meanwhile,there were spatial differences in carrying capacity and carrying status of ecosystem in Haixi Zone,which is helpful to sound development of social-economic,sustainable usage of ecosystem service and effective maintenance of ecological security.

  7. 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

  8. 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

  9. 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。

  10. A comparison of currents carried by HERG, with and without coexpression of MiRP1, and the native rapid delayed rectifier current. Is MiRP1 the missing link?

    Science.gov (United States)

    Weerapura, Manjula; Nattel, Stanley; Chartier, Denis; Caballero, Ricardo; Hébert, Terence E

    2002-04-01

    Although it has been suggested that coexpression of minK related peptide (MiRP1) is required for reconstitution of native rapid delayed-rectifier current (I(Kr)) by human ether-a-go-go related gene (HERG), currents resulting from HERG (I(HERG)) and HERG plus MiRP1 expression have not been directly compared with native I(Kr). We compared the pharmacological and selected biophysical properties of I(HERG) with and without MiRP1 coexpression in Chinese hamster ovary (CHO) cells with those of guinea-pig I(Kr) under comparable conditions. Comparisons were also made with HERG expressed in Xenopus oocytes. MiRP1 coexpression significantly accelerated I(HERG) deactivation at potentials negative to the reversal potential, but did not affect more physiologically relevant deactivation of outward I(HERG), which remained slower than that of I(Kr). MiRP1 shifted I(HERG) activation voltage dependence in the hyperpolarizing direction, whereas I(Kr) activated at voltages more positive than I(HERG). There were major discrepancies between the sensitivity to quinidine, E-4031 and dofetilide of I(HERG) in Xenopus oocytes compared to I(Kr), which were not substantially affected by coexpression with MiRP1. On the other hand, the pharmacological sensitivity of I(HERG) in CHO cells was indistinguishable from that of I(Kr) and was unaffected by MiRP1 coexpression. We conclude that the properties of I(HERG) in CHO cells are similar in many ways to those of native I(Kr) under the same recording conditions, and that the discrepancies that remain are not reduced by coexpression with MiRP1. These results suggest that the physiological role of MiRP1 may not be to act as an essential consituent of the HERG channel complex carrying native I(Kr).

  11. 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.

  12. Non-axisymmetric equilibrium reconstruction of a current-carrying stellarator using external magnetic and soft x-ray inversion radius measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ma, X., E-mail: xzm0005@auburn.edu; Maurer, D. A.; Knowlton, S. F.; ArchMiller, M. C.; Ennis, D. A.; Hanson, J. D.; Hartwell, G. J.; Hebert, J. D.; Herfindal, J. L.; Pandya, M. D.; Roberds, N. A.; Traverso, P. J. [Physics Department, Auburn University, Auburn, Alabama 36849 (United States); Cianciosa, M. R. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37830 (United States)

    2015-12-15

    Non-axisymmetric free-boundary equilibrium reconstructions of stellarator plasmas are performed for discharges in which the magnetic configuration is strongly modified by ohmically driven plasma current. These studies were performed on the compact toroidal hybrid device using the V3FIT reconstruction code with a set of 50 magnetic diagnostics external to the plasma. With the assumption of closed magnetic flux surfaces, the reconstructions using external magnetic measurements allow accurate estimates of the net toroidal flux within the last closed flux surface, the edge safety factor, and the plasma shape of these highly non-axisymmetric plasmas. The inversion radius of standard sawteeth is used to infer the current profile near the magnetic axis; with external magnetic diagnostics alone, the current density profile is imprecisely reconstructed.

  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. 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

  15. 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%.

  16. 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

  17. Three dimensional equilibrium solutions for a current-carrying reversed-field pinch plasma with a close-fitting conducting shell

    Energy Technology Data Exchange (ETDEWEB)

    Koliner, J. J.; Boguski, J., E-mail: boguski@wisc.edu; Anderson, J. K.; Chapman, B. E.; Den Hartog, D. J.; Duff, J. R.; Goetz, J. A.; McGarry, M.; Morton, L. A.; Parke, E. [Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Cianciosa, M. R. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Hanson, J. D. [Department of Physics, Auburn University, Auburn, Alabama 36849 (United States); Brower, D. L.; Ding, W. X. [Department of Physics and Astronomy, University of California, Los Angeles, California 90095 (United States)

    2016-03-15

    In order to characterize the Madison Symmetric Torus (MST) reversed-field pinch (RFP) plasmas that bifurcate to a helical equilibrium, the V3FIT equilibrium reconstruction code was modified to include a conducting boundary. RFP plasmas become helical at a high plasma current, which induces large eddy currents in MST's thick aluminum shell. The V3FIT conducting boundary accounts for the contribution from these eddy currents to external magnetic diagnostic coil signals. This implementation of V3FIT was benchmarked against MSTFit, a 2D Grad-Shafranov solver, for axisymmetric plasmas. The two codes both fit B{sub θ} measurement loops around the plasma minor diameter with qualitative agreement between each other and the measured field. Fits in the 3D case converge well, with q-profile and plasma shape agreement between two distinct toroidal locking phases. Greater than 60% of the measured n = 5 component of B{sub θ} at r = a is due to eddy currents in the shell, as calculated by the conducting boundary model.

  18. Three dimensional equilibrium solutions for a current-carrying reversed-field pinch plasma with a close-fitting conducting shell

    Science.gov (United States)

    Koliner, J. J.; Cianciosa, M. R.; Boguski, J.; Anderson, J. K.; Hanson, J. D.; Chapman, B. E.; Brower, D. L.; Den Hartog, D. J.; Ding, W. X.; Duff, J. R.; Goetz, J. A.; McGarry, M.; Morton, L. A.; Parke, E.

    2016-03-01

    In order to characterize the Madison Symmetric Torus (MST) reversed-field pinch (RFP) plasmas that bifurcate to a helical equilibrium, the V3FIT equilibrium reconstruction code was modified to include a conducting boundary. RFP plasmas become helical at a high plasma current, which induces large eddy currents in MST's thick aluminum shell. The V3FIT conducting boundary accounts for the contribution from these eddy currents to external magnetic diagnostic coil signals. This implementation of V3FIT was benchmarked against MSTFit, a 2D Grad-Shafranov solver, for axisymmetric plasmas. The two codes both fit Bθ measurement loops around the plasma minor diameter with qualitative agreement between each other and the measured field. Fits in the 3D case converge well, with q-profile and plasma shape agreement between two distinct toroidal locking phases. Greater than 60% of the measured n = 5 component of Bθ at r = a is due to eddy currents in the shell, as calculated by the conducting boundary model.

  19. 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.

  20. 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。

  1. 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.

  2. Nonequilibrium spin texture within a thin layer below the surface of current-carrying topological insulator Bi2 Se3 : A first-principles quantum transport study

    Science.gov (United States)

    Chang, Po-Hao; Nikolic, Branislav; Markussen, Troels; Smidstrup, Søren; Stokbro, Kurt

    Using extension of nonequilibrium Green function combined with density functional theory (NEGF+DFT) formalism to situations involving noncollinear spins and spin-orbit coupling, we investigate microscopic details (on the 1 ° A scale) of nonequilibrium spin density S(r) driven by unpolarized charge current injection into a ballistic thin film of Bi 2 Se 3 as prototypical topological insulator (TI) material. We find large nonzero component of S(r) in the direction transverse to current flow on the metallic surfaces of TI, as well as within few bulk atomic layers near the surfaces because of penetration of evanescent wavefunctions from the metallic surfaces into the bulk. In addition, an order of magnitude smaller components emerge in the perpendicular (within surfaces and nearly bulk regions of TI) and longitudinal (within bulk region of TI near its surface) directions, thereby creating a complex nonequilibrium spin texture. We also demonstrate how DFT calcula- tions with properly optimized local orbital basis set can precisely match putatively more accurate calculations with plane wave basis set for the supercell of Bi 2 Se 3 . P.-H.C. and B.K.N. were supported by NSF Grant No. 281 FQ ECCS 1509094. The supercomputing time was provided by 282 XSEDE, which is supported by NSF Grant No. ACI-1053575. 283 QuantumWise acknowledges support from the Danish Inno-284 vation Fund Grant No.

  3. 30 CFR 77.503 - Electric conductors; capacity and insulation.

    Science.gov (United States)

    2010-07-01

    ... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and insulation. Electric conductors shall be sufficient in size and have adequate current carrying capacity and be of such... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductors; capacity and...

  4. 30 CFR 75.513 - Electric conductor; capacity and insulation.

    Science.gov (United States)

    2010-07-01

    ... § 75.513 Electric conductor; capacity and insulation. All electric conductors shall be sufficient in size and have adequate current carrying capacity and be of such construction that a rise in temperature... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductor; capacity and insulation....

  5. Can Brazil play a more important role in global tuberculosis drug production? An assessment of current capacity and challenges.

    Science.gov (United States)

    Gemal, Andre; Keravec, Joel; Menezes, Alexandre; Trajman, Anete

    2013-03-27

    Despite the existence of effective treatment, tuberculosis is still a global public health issue. The World Health Organization recommends a six-month four-drug regimen in fixed-dose combination formulation to treat drug sensitive tuberculosis, and long course regimens with several second-line drugs to treat multi-drug resistant tuberculosis. To achieve the projected tuberculosis elimination goal by 2050, it will be essential to ensure a non-interrupted supply of quality-assured tuberculosis drugs. However, quality and affordable tuberculosis drug supply is still a significant challenge for National Tuberculosis Programs. Quality drug production requires a combination of complex steps. The first challenge is to guarantee the quality of tuberculosis active pharmaceutical ingredients, then ensure an adequate manufacturing process, according to international standards, to guarantee final product's safety, efficacy and quality. Good practices for storage, transport, distribution and quality control procedures must follow. In contrast to other high-burden countries, Brazil produces tuberculosis drugs through a strong network of public sector drug manufacturers regulated by a World Health Organization-certified national sanitary authority. The installed capacity for production surpasses the 71,000 needed treatments in the country. However, in order to be prepared to act as a global supplier, important bottlenecks are to be overcome. This article presents an in-depth analysis of the current status of production of tuberculosis drugs in Brazil and the bottlenecks and opportunities for the country to sustain national demand and play a role as a potential global supplier. Raw material and drug production, quality control, international certification and pre-qualification, political commitment and regulatory aspects are discussed, as well recommendations for tackling these bottlenecks. This discussion becomes more important as new drugs and regimens to treat tuberculosis are

  6. Reduced-Capacity Inrush Current Suppressor Using a Matrix Converter in a Wind Power Generation System with Squirrel-Cage Induction Machines

    Directory of Open Access Journals (Sweden)

    Sho Shibata

    2016-03-01

    Full Text Available This paper describes the reduced capacity of the inrush current suppressor using a matrix converter (MC in a large-capacity wind power generation system (WPGS with two squirrel-cage induction machines (SCIMs. These SCIMs are switched over depending on the wind speed. The input side of the MC is connected to the source in parallel. The output side of the MC is connected in series with the SCIM through matching transformers. The modulation method of the MC used is direct duty ratio pulse width modulation. The reference output voltage of the MC is decided by multiplying the SCIM current with the variable control gain. Therefore, the MC performs as resistors for the inrush current. Digital computer simulation is implemented to confirm the validity and practicability of the proposed inrush current suppressor using PSCAD/EMTDC (power system computer-aided design/electromagnetic transients including DC. Furthermore, the equivalent resistance of the MC is decided by the relationship between the equivalent resistance and the capacity of the MC. Simulation results demonstrate that the proposed inrush current suppressor can suppress the inrush current perfectly.

  7. 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

  8. 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

  9. An automatic method to analyze the Capacity-Voltage and Current-Voltage curves of a sensor

    CERN Document Server

    Matorras Cuevas, Pablo

    2017-01-01

    An automatic method to perform Capacity versus voltage analysis for all kind of silicon sensor is provided. It successfully calculates the depletion voltage to unirradiated and irradiated sensors, and with measurements with outliers or reaching breakdown. It is built using C++ and using ROOT trees with an analogous skeleton as TRICS, where the data as well as the results of the ts are saved, to make further analysis.

  10. The Implementation Of Solid State Switches In A Parallel Configuration To Gain Output Current Capacity In A High Current Capacitive Discharge Unit (CDU).

    Energy Technology Data Exchange (ETDEWEB)

    Chaves, Mario Paul [Univ. of New Mexico, Albuquerque, NM (United States)

    2017-07-01

    For my project I have selected to research and design a high current pulse system, which will be externally triggered from a 5V pulse. The research will be conducted in the region of paralleling the solid state switches for a higher current output, as well as to see if there will be any other advantages in doing so. The end use of the paralleled solid state switches will be used on a Capacitive Discharge Unit (CDU). For the first part of my project, I have set my focus on the design of the circuit, selection of components, and simulation of the circuit.

  11. 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...

  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. Exploration and comparison of inborn capacity of aerobic and anaerobic metabolisms of Saccharomyces cerevisiae for microbial electrical current production

    Science.gov (United States)

    Mao, Longfei; Verwoerd, Wynand S

    2013-01-01

    Saccharomyces cerevisiae possesses numerous advantageous biological features, such as being robust, easily handled, mostly non-pathogenic and having high catabolic rates, etc., which can be considered as merits for being used as a promising biocatalyst in microbial fuel cells (MFCs) for electricity generation. Previous studies have developed efficient MFC configurations to convert metabolic electron shuttles, such as cytoplasmic NADH, into usable electric current. However, no studies have elucidated the maximum potential of S. cerevisiae for current output and the underlying metabolic pathways, resulting from the interaction of thousands of reactions inside the cell during MFC operation. To address these two key issues, this study used in silico metabolic engineering techniques, flux balance analysis (FBA), and flux variability analysis with target flux minimization (FATMIN), to model the metabolic perturbation of S. cerevisiae under the MFC-energy extraction. The FBA results showed that, in the cytoplasmic NADH-dependent mediated electron transfer (MET) mode, S. cerevisiae had a potential to produce currents at up to 5.781 A/gDW for the anaerobic and 6.193 A/gDW for the aerobic environments. The FATMIN results showed that the aerobic and anaerobic metabolisms are resilient, relying on six and five contributing reactions respectively for high current production. Two reactions, catalyzed by glutamate dehydrogenase (NAD) (EC 1.4.1.3) and methylene tetrahydrofolate dehydrogenase (NAD) (EC 1.5.1.5), were shared in both current-production modes and contributed to over 80% of the identified maximum current outputs. It is also shown that the NADH regeneration was much less energy costly than biomass production rate. Taken together, our finding suggests that S. cerevisiae should receive more research effort for MFC electricity production. PMID:23969939

  14. Region-wide assessment of the capacity for human nutrition training in West Africa: current situation, challenges, and way forward

    Directory of Open Access Journals (Sweden)

    Roger Sodjinou

    2014-01-01

    Full Text Available Background: There is a dearth of information on existing nutrition training programs in West Africa. A preliminary step in the process of developing a comprehensive framework to strengthen human capacity for nutrition is to conduct an inventory of existing training programs. Objective: This study was conducted to provide baseline data on university-level nutrition training programs that exist in the 16 countries in West Africa. It also aimed to identify existing gaps in nutrition training and propose solutions to address them. Design: Participating institutions were identified based on information provided by in-country key informants, UNICEF offices or through internet searches. Data were collected through semi-structured interviews during on-site visits or through self-administered questionnaires. Simple descriptive and bivariate analyses were performed. Results: In total, 83 nutrition degree programs comprising 32 B.Sc. programs, 34 M.Sc. programs, and 17 Ph.D. programs were identified in the region. More than half of these programs were in Nigeria. Six countries (Cape Verde, Guinea-Bissau, Liberia, Mali, The Gambia, and Togo offered no nutrition degree program. The programs in francophone countries were generally established more recently than those in anglophone countries (age: 3.5 years vs. 21.4 years. Programs were predominantly (78% run by government-supported institutions. They did not provide a comprehensive coverage of all essential aspects of human nutrition. They were heavily oriented to food science (46%, with little emphasis on public health nutrition (24% or overnutrition (2%. Annual student intakes per program in 2013 ranged from 3 to 262; 7 to 40; and 3 to 10, respectively, for bachelor's, master's, and doctoral programs while the number of graduates produced annually per country ranged from 6 to 271; 3 to 64; and 1 to 18, respectively. External collaboration only existed in 15% of the programs. In-service training programs on

  15. Region-wide assessment of the capacity for human nutrition training in West Africa: current situation, challenges, and way forward.

    Science.gov (United States)

    Sodjinou, Roger; Fanou, Nadia; Deart, Lucie; Tchibindat, Félicité; Baker, Shawn; Bosu, William; Pepping, Fré; Delisle, Hélène

    2014-01-01

    There is a dearth of information on existing nutrition training programs in West Africa. A preliminary step in the process of developing a comprehensive framework to strengthen human capacity for nutrition is to conduct an inventory of existing training programs. This study was conducted to provide baseline data on university-level nutrition training programs that exist in the 16 countries in West Africa. It also aimed to identify existing gaps in nutrition training and propose solutions to address them. Participating institutions were identified based on information provided by in-country key informants, UNICEF offices or through internet searches. Data were collected through semi-structured interviews during on-site visits or through self-administered questionnaires. Simple descriptive and bivariate analyses were performed. In total, 83 nutrition degree programs comprising 32 B.Sc. programs, 34 M.Sc. programs, and 17 Ph.D. programs were identified in the region. More than half of these programs were in Nigeria. Six countries (Cape Verde, Guinea-Bissau, Liberia, Mali, The Gambia, and Togo) offered no nutrition degree program. The programs in francophone countries were generally established more recently than those in anglophone countries (age: 3.5 years vs. 21.4 years). Programs were predominantly (78%) run by government-supported institutions. They did not provide a comprehensive coverage of all essential aspects of human nutrition. They were heavily oriented to food science (46%), with little emphasis on public health nutrition (24%) or overnutrition (2%). Annual student intakes per program in 2013 ranged from 3 to 262; 7 to 40; and 3 to 10, respectively, for bachelor's, master's, and doctoral programs while the number of graduates produced annually per country ranged from 6 to 271; 3 to 64; and 1 to 18, respectively. External collaboration only existed in 15% of the programs. In-service training programs on nutrition existed in less than half of the countries

  16. 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 .

  17. 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

  18. 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.

  19. History and modern applications of nano-composite materials carrying GA/cm2 current density due to a Bose-Einstein Condensate at room temperature produced by Focused Electron Beam Induced Processing for many extraordinary novel technical applications

    Science.gov (United States)

    Koops, Hans W. P.

    2015-12-01

    The discovery of Focused Electron Beam Induced Processing and early applications of this technology led to the possible use of a novel nanogranular material “Koops-GranMat®” using Pt/C and Au/C material. which carries at room temperature a current density > 50 times the current density which high TC superconductors can carry. The explanation for the characteristics of this novel material is given. This fact allows producing novel products for many applications using Dual Beam system having a gas supply and X.Y.T stream data programming and not using GDSII layout pattern control software. Novel products are possible for energy transportation. -distribution.-switching, photon-detection above 65 meV energy for very efficient energy harvesting, for bright field emission electron sources used for vacuum electronic devices like amplifiers for HF electronics, micro-tubes, 30 GHz to 6 THz switching amplifiers with signal to noise ratio >10(!), THz power sources up to 1 Watt, in combination with miniaturized vacuum pumps, vacuum gauges, IR to THz detectors, EUV- and X-Ray sources. Since focusing electron beam induced deposition works also at low energy, selfcloning multibeam-production machines for field emitter lamps, displays, multi-beam - lithography, - imaging, and - inspection, energy harvesting, and power distribution with switches controlling field-emitter arrays for KA of currents but with < 100 V switching voltage are possible. Finally the replacement of HTC superconductors and its applications by the Koops-GranMat® having Koops-Pairs at room temperature will allow the investigation devices similar to Josephson Junctions and its applications now called QUIDART (Quantum interference devices at Room Temperature). All these possibilities will support a revolution in the optical, electric, power, and electronic technology.

  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. High-speed deposition of RE123 film with large current capacity by hot-wall type PLD system

    Energy Technology Data Exchange (ETDEWEB)

    Igarashi, M., E-mail: m_igarashi@fujikura.co.j [Fujikura Ltd., 1440 Mutsuzaki, Sakura, Chiba 285-8550 (Japan); Kakimoto, K.; Hayashida, T.; Hanada, Y.; Fujita, S.; Morita, K.; Nakamura, N.; Hanyu, S.; Sutoh, Y.; Kutami, H.; Iijima, Y.; Saitoh, T. [Fujikura Ltd., 1440 Mutsuzaki, Sakura, Chiba 285-8550 (Japan)

    2010-11-01

    We have studied a hot-wall heating system to produce GdBa{sub 2}Cu{sub 3}O{sub y} (GdBCO) films with large critical currents (I{sub c}) at a high production rate by a pulsed-laser-deposition (PLD) method. GdBCO films fabricated at a production rate of 30 m/h under the optimized conditions, especially a distance of 95 mm between the target and the substrate (T-S), exhibited high critical current densities (J{sub c}) of about 3 MA/cm{sup 2} and I{sub c} over 300 A at a thickness of 1-2 {mu}m. Furthermore, long GdBCO tapes prepared by repeated depositions at each tape-passing speed of 80 m/h showed uniform I{sub c} distribution along the longitudinal direction, because the hot-wall system enabled to stabilize temperature within a few degrees at 800 deg. C. A 170 m long tape with I{sub c} over 600 A was successfully fabricated at a production rate of 16 m/h using a laser power of 360 W.

  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. Alternating current calorimeter for specific heat capacity measurements at temperatures below 10 K and pressures up to 10 GPa.

    Science.gov (United States)

    Umeo, Kazunori

    2016-06-01

    A developed alternating current calorimeter for measuring the absolute value of specific heat C of a very small sample under a pressure up to 10 GPa and low temperature below 10 K is described. A Bridgman anvil cell made of tungsten carbide with a top diameter of 3 mm is used. A hollow at the top prevents expansion of the sample space over the anvil top. Two chip resistors, which act as a thermometer and a heater, are mounted on the outer part of a copper-beryllium gasket with a frying pan-like shape. Thus, the thermometer is not pressurized. In order to isolate the gasket from the anvil thermally, diamond powder with a grain size of 0.25 μm is placed on the anvil top. Two jumps of C at the superconducting transitions of Pb (3.3 mg) and In (5.0 mg) are observed under various pressures up to 9 GPa, as clearly as those at the ambient pressure.

  4. Assessment of current and proposed nature reserves of Mexico based on their capacity to protect geophysical features and biodiversity

    Science.gov (United States)

    Cantu, C.; Wright, R.G.; Scott, J.M.; Strand, Espen

    2004-01-01

    Mexico currently has 144 nature reserves covering approximately 9.1% of its land area. These reserves were established for a variety of reasons - often unrelated to the protection of biodiversity. In 2000 in response to a growing concern about the lack of organized conservation reserve planning to protect the important threatened biological and physical features of Mexico, the Mexican Commission for Knowledge and Use of Biodiversity (CONABIO) proposed the establishment of 151 new reserves for Mexico covering 51,429,500 ha. We compiled a GIS analysis using digital thematic maps of physical and biological features to examine how the existing and proposed reserves serve to protect the biodiversity and physical features of the country. Using a conservation target of placing a minimum of 12% of the land area of each important biophysical feature in nature reserves, we found that the 144 existing nature reserves covering 18 million ha (9% of the country) only meet that target for elevation ranges >3000 m and areas with poor soils. These mountainous areas represent less than 1% of the country. The gaps in the existing nature reserves network occur mainly at lower and intermediate elevations (ecosystems, and high productivity soils. The areas proposed by CONABIO increase the proportion of protected lands in the country to over 27% and most of the conservation targets for geophysical features, and land cover, categories are met. Whether this area would be sufficient to maintain viable populations and ecological integrity of species and ecosystems is unknown. Even with the new reserves, low elevation coastal lands would be below the conservation target in the nature reserves. To include a representative sample of these lands would be difficult as these are the same areas where the majority of people live. ?? 2003 Elsevier Ltd. All rights reserved.

  5. 弥散铜导电条的制备及其组织性能分析%Preparation of ODSC Current-carrying Plate and Analysis of Its Microstructure and Properties

    Institute of Scientific and Technical Information of China (English)

    岳灿甫; 陈会东; 雷竹芳; 金建新; 陈派明

    2012-01-01

    使用雾化法制备铜-铝合金粉,采用内氧化法制备锭坯,热挤压锭坯制备弥散铜棒材,然后经拉伸和轧制棒材法制备弥散铜导电条,并对Al2O3弥散强化铜合金导电条的组织与性能进行了分析.结果表明,制备的弥散铜导电条厚1~25 mm,制备的弥散铜导电条中铝含量分别为0.19%、0.12%; 0.12%Al含量的弥散铜导电条抗拉强度为495 MPa,导电率≥92%IACS;0.19%Al含量的弥散铜导电条抗拉强度为530 MPa,导电率≥87%IACS.%The ingot of aluminum oxide dispersion strengthened copper alloy (ODSC) was produced by using atomized Cu-Al powder by adopting internal oxidation method. The rods were produced by hot extrusion method. The current-carrying plate was produced by cold drawing the rods and then cold rolling. The size of ODSC current-carrying plate was 1 -25 mm. The produced plates had two brand with 0.12%Al, 0.19%Al. Tensile strength of the copper alloy with 0.12%Al is 495 Mpa, and its conductivity is more than 92%1ACS; the tensile strength of the copper alloy with 0.19% Al is 530 Mpa, and its conductivity is 87%IACS.

  6. 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.

  7. 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

  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. 蓄电池恒流放电容量监测仪的电路设计%Circuit Design of Constant Current Discharge Capacity Monitor for Battery

    Institute of Scientific and Technical Information of China (English)

    付晓伟; 普仕凡

    2013-01-01

    蓄电池恒流放电容量监测仪以单片机为核心,以PTC热敏电阻为放电负载;采用PWM技术控制电流恒定,实时监测放电电池的电流电压;采用大电流恒流放电方法,对蓄电池进行活化处理延长寿命.由ATmega128单片机、电源、存储器及时间芯片组成基础电路,由触摸屏、LCD显示模块、数据采集电路、PWM信号驱动电路组成显控驱动电路,监测仪则由二者共同构成.介绍了硬件构成与电路设计的思路.%In the constant current discharge capacity monitor for battery, microcontroller is taken as core and PTC thermistor is taken as discharge load, PWM technique is used to control current constant, the current and voltage of discharge battery is real-time monitored, the discharge means of heavy current constant current is a dopted to activate the battery and lengthen the life of it. The basic circuit consists of ATmegal28, power, memo ry and time chips, the display control drive circuit is composed of the touch screen, LCD display module, data acquisition circuit and PWM signal driving circuit, and the monitor is constituted together by the two circuits. The design idea of the hardware structure and circuit is introduced.

  11. 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.

  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. 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

  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. 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

  19. Local Dynamic Stability Associated with Load Carrying

    Directory of Open Access Journals (Sweden)

    Jian Liu

    2013-03-01

    Conclusion: Current study confirmed the sensitivity of local dynamic stability measure in load carrying situation. It was concluded that load carrying tasks were associated with declined local dynamic stability, which may result in increased risk of fall accident. This finding has implications in preventing fall accidents associated with occupational load carrying.

  20. Running Characteristics Analysis of Electromagnetic Coil Launcher With Current-carrying Armature%载流电枢电磁线圈发射器运行特性分析

    Institute of Scientific and Technical Information of China (English)

    金洪波; 曹延杰; 王成学; 王慧锦

    2016-01-01

    The armature is the key part for energy exchange in electromagnetic coil launcher (EMCL).The structural model with series-current armature launcher ( SCCAL ) and parallel-current armature launcher ( PCCAL) was proposed .System differential equation was deduced by analyzing the working principle and the structure character of two kinds of current-carrying armature launcher ( CCAL) .Systematical model of the CCAL was built with MATLAB , and the launching character was analyzed .The analysis shows that there is no pulling effect in launching process in CCAL .SCCAL is more suitable for accelerating payload with low-velocity less than 20 m/s by using low-voltage-capacitor power-supply .PCCAL can be used to accelerating payload with high velocity more over 50 m/s by using high-voltage-capacitor power-supply . The conclusion has great significance for guiding the structural design in EMCL .%电枢是电磁线圈发射器能量转换的关键部分,以此为研究对象,提出串联载流电枢发射器和并联载流电枢发射器的结构模型,通过分析2种载流电枢发射器的工作原理和结构特点,得到了系统微分方程,并利用MATLAB建立了载流电枢发射器的系统仿真模型,分析了发射器的运行特性。分析结果表明,载流电枢发射器发射过程无拖拽效应,串联载流电枢发射器适于载荷在20 m/s以下的加速段使用,适于选用低压的电容器电源;并联载流电枢发射器可用于载荷在50 m/s以上的加速段使用,适于选用高电压电容器。研究结果对电磁线圈发射器电枢结构设计具有一定的指导意义。

  1. 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

  2. 载流梁的热磁弹性3次超谐共振%Third Superharmonic Resonance of the Current-Carrying Beam in Thermal-Magneto-Elasticity Field

    Institute of Scientific and Technical Information of China (English)

    席晓燕

    2014-01-01

    在磁弹性动力学理论的基础上,应用动力学方法建立电磁场和温度场联合作用下的载流梁的非线性热磁弹性振动方程。应用非线性振动的多尺度法,求得了系统受Lorentz力和温度影响共同作用的3次超谐共振幅频响应方程,并对其进行了数值计算,研究电磁场、温度变化、电流、几何参数等参数对载流梁3次超谐共振响应曲线的影响。结果表明:当温度、磁场强度、长度、横截面积达到特定值时,系统振幅会大幅增加。%Based on the electro-magneto-elastic theory, nonlinear vibration equation of current-carrying beam in thermal-magneto-elasticity field is studied. The Lorentz force and temperature effect on the beam are derived. According to the method of multiple scales for nonlinear vibrations the amplitude frequency response equation of third superharmonic resonance is obtained. The effects of electro-magnetic and mechanical parameters on system res-onance characteristics are analyzed. The results show the amplitude of system will substantially increase when the temperature,magnetic field intensity,length,cross-sectional area reach their certain values respectively.

  3. 大容量高速限流开关的设计与试验研究%Design and Test Study of Large Capacity High Speed Current Limit Switch

    Institute of Scientific and Technical Information of China (English)

    李健; 朱峰

    2011-01-01

    针对现有保护设备难以满足大容量电力系统短路保护要求的问题,研制了一种基于爆炸活塞式高速开断器和灭弧熔断器的混合型限流保护装置,设计了额定640V/2500A的工程样机,并进行了高速开断器的分断试验和整机的限流试验。试验结果表明,该保护装置限流效果显著,全分断时fHJ仪为2.5ms,大大提高了电力系统的安全性。%Aiming at the problem that the existing protection equipment is difficult to meet large capacity power system short circuit protective requirements problem, this paper researched a kind of high speed break-off device based on explosive piston type and arc blow-out fuse mixed type, current limit protection device, designing rated voltage 640 V/2 500 A engineering sample machine. The break-off test and whole machine current limit test were carried out for high speed breaker. Test result shows that the protective device current limit effect is obvious and the total break-offtime is only 2.5 ms, which greatly raises safety of the power system.

  4. 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。

  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. The interaction of approach-alcohol action tendencies, working memory capacity, and current task goals predicts the inability to regulate drinking behavior.

    Science.gov (United States)

    Sharbanee, Jason M; Stritzke, Werner G K; Wiers, Reinout W; Young, Paul; Rinck, Mike; MacLeod, Colin

    2013-09-01

    The inability to regulate alcohol consumption has been attributed to an imbalance between stimulus-driven behavioral biases, or action tendencies, and the ability to exert goal-directed control, or working memory capacity (WMC). Previous research assessing the interaction between these variables has not considered the effect of whether individuals' current goals or task demands require goal-directed control. Our aim was to examine the potential interaction of appetitive action tendencies and the ability to exert control over these action tendencies as a function of whether task demands require applying control for successful task completion. Two groups of social drinkers (n = 40 per group) who differed in their ability to regulate their alcohol consumption completed a novel variant of the Approach-Avoidance Task (AAT), which separately assessed approach and avoid trials. The approach and avoidance responses differentially require goal-directed control, depending on whether the task-relevant response is incongruent with the stimulus-driven action tendency. Results indicated that (a) group differences in AAT indices were only observed on trials that required an avoidance movement, which are trials where the task-relevant response would be incongruent with an approach action tendency, and (b) the extent of the group differences for these avoidance trials was moderated by individual differences in WMC, such that problem drinkers with lower WMC showed greater behavioral bias toward alcohol than those with higher WMC. These findings suggest that difficulties in regulating alcohol consumption arise from a complex interaction of action-tendencies, WMC, and current goals or task demands.

  7. Multiple pulse-heating experiments with different current to determine total emissivity, heat capacity, and electrical resistivity of electrically conductive materials at high temperatures.

    Science.gov (United States)

    Watanabe, Hiromichi; Yamashita, Yuichiro

    2012-01-01

    A modified pulse-heating method is proposed to improve the accuracy of measurement of the hemispherical total emissivity, specific heat capacity, and electrical resistivity of electrically conductive materials at high temperatures. The proposed method is based on the analysis of a series of rapid resistive self-heating experiments on a sample heated at different temperature rates. The method is used to measure the three properties of the IG-110 grade of isotropic graphite at temperatures from 850 to 1800 K. The problem of the extrinsic heating-rate effect, which reduces the accuracy of the measurements, is successfully mitigated by compensating for the generally neglected experimental error associated with the electrical measurands (current and voltage). The results obtained by the proposed method can be validated by the linearity of measured quantities used in the property determinations. The results are in reasonably good agreement with previously published data, which demonstrate the suitability of the proposed method, in particular, to the resistivity and total emissivity measurements. An interesting result is the existence of a minimum in the emissivity of the isotropic graphite at around 1120 K, consistent with the electrical resistivity results.

  8. 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

  9. 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

  10. 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

    the P were loaded from animal production sites. The mean animal density in the watershed was currently 3.46 AU · hm-2. The current NP inputs to farmlands was 35.8 kg and 18.6 kg-hm-2 in the watershed. Based on an estimate for the environmental adaptation capacity ( EAC) of N and P in the watershed, the current animal density was 2.4 times larger than the critical density (1.13 AU·hm -2 ) of the EAC for the watershed under the current N and P fertilizer inputs levels. Assuming that 30% of N discharge for animal production is re-used by farmlands, the animal density under the EAC can be set at 2.74 AU·hm -2 (equivalent to 195 ,000 pigs for slaughter every year). Thus, we propose to reconstruct the agricultural systems by reducing animal production and establishing an integrating crop and animal farming systems.

  11. 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.

  12. Impact of Cretaceous Climate on Upwelling and Erosive Capacity of Transequatorial Current in the Tethys Seaway - Tales from Deep-Sea Sediments

    Science.gov (United States)

    Weissert, H.; Wohlwend, S.

    2014-12-01

    Early Cretaceous sedimentary archives from the Atlantic and Tethys Ocean record a reorganization of ocean circulation triggered by a further opening and deepening oft the Hispanic corridor. Nannofossil ooze, deposited in Atlantic and Tethys Oceans during earliest Cretaceous mirrors a stable equatorial circulation pattern with oligotrophic surface water conditions. Tethyan limestone-marlstone deposits and dark clays in the western North Atlantic mark reorganization of circulation pattern dominating Valanginian-Albian oceanography and favoring episodic black shale formation in Atlantic and Tethys Ocean. An east-west directed trans-equatorial current (TEC), coupled with equatorial upwelling and with varying erosive capacity was established (Hotinski and Toggweiler, Paleoceanography, 2003). Aptian sedimentary records from Tethys and Atlantic Oceans provide information on the sensitivity of the TEC to changing climate at times of perturbed carbon cycling as registered in the carbon isotope record. A greenhouse pulse defines the base of Aptian Oceanic Anoxic Event (OAE) 1a, while available temperature and pCO2 records point at post-OAE1a cooling of climate. In the eastern Tethys (Oman Mts), the Aptian greenhouse pulse coincides with onset of chert deposits at a time of a shallowing CCD and of increased upwelling. Well-ventilated Pacific-type deep-water conditions prevented the formation of black shales in the deep Hawasina Basin (Oman Mts). Low oxygen or anoxic conditions, however, favored black shale formation in basinal settings of the Western Tethys and Atlantic Ocean. Frequent sedimentary gaps in basinal successions and erosive surfaces, sometimes phosphatized, on alpine Tethyan submarine highs and along the Northern Tethyan shelf provide evidence for increased erosive power of the TEC, reaching depths of up to 1000m or more. If increased erosive power of TEC was triggered by the greenhouse pulse or by post-OAE1a cooling remains to be tested.

  13. 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

  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. 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;

  16. 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

  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. The interaction of approach-alcohol action tendencies, working memory capacity, and current task goals predicts the inability to regulate drinking behavior

    NARCIS (Netherlands)

    Sharbanee, J.M.; Stritzke, W.G.K.; Wiers, R.W.H.J.; Young, P.; Rinck, M.; McLeod, C.

    2013-01-01

    The inability to regulate alcohol consumption has been attributed to an imbalance between stimulus-driven behavioral biases, or action tendencies, and the ability to exert goal-directed control, or working memory capacity (WMC). Previous research assessing the interaction between these variables has

  19. Region-wide assessment of the capacity for human nutrition training in West Africa: current situation,challenges, and way forward

    NARCIS (Netherlands)

    Sodjinou, R.; Fanou, N.; Deart, L.; Pepping, F.

    2014-01-01

    Background: There is a dearth of information on existing nutrition training programs in West Africa. A preliminary step in the process of developing a comprehensive framework to strengthen human capacity for nutrition is to conduct an inventory of existing training programs. Objective: This study wa

  20. Region-wide assessment of the capacity for human nutrition training in West Africa: current situation,challenges, and way forward

    NARCIS (Netherlands)

    Sodjinou, R.; Fanou, N.; Deart, L.; Pepping, F.

    2014-01-01

    Background: There is a dearth of information on existing nutrition training programs in West Africa. A preliminary step in the process of developing a comprehensive framework to strengthen human capacity for nutrition is to conduct an inventory of existing training programs. Objective: This study

  1. 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。

  2. 分层损伤和完好复合材料薄壁加筋板的