WorldWideScience

Sample records for adjoing managed stand

  1. Economics of stand management

    Science.gov (United States)

    David K. Lewis

    1986-01-01

    This paper sets out to demonstrate the importance of considering the wealth represented by the growing stock in economic analyses of stand management alternatives, and to demonstrate the role of thinning in the manipulation of the efficiency of growing stock in the management of shortleaf pine (Pinus echinata Mill.). These goals are achieved through a demonstration of...

  2. Principles of managing stands

    Science.gov (United States)

    David A. Marquis; Rodney Jacobs

    1989-01-01

    Forest stands are managed to achieve some combination of desired products or values. These products or values may include income and tangible benefits from timber production or fees for hunting rights and other recreational activities. The values may be intangible, such as the enjoyment of seeing wildlife or flowering plants, or the simple satisfaction of knowing that...

  3. Economic considerations of managing stands

    Science.gov (United States)

    Gary W. Miller

    1989-01-01

    Managing central hardwood stands involves making choices. Each year landowners face at least three alternatives for managing a stand: (1) allow it to grow undisturbed, (2) undertake a partial or complete commercial harvest, or (3) culture the timber crop through a precommercial investment. Each activity affects long-term monetary returns. The "best" choice in...

  4. Management alternatives of energy wood thinning stands

    International Nuclear Information System (INIS)

    Heikkilae, Jani; Siren, Matti; Aeijaelae, Olli

    2007-01-01

    Energy wood thinning has become a feasible treatment alternative of young stands in Finland. Energy wood thinnings have been carried out mainly in stands where precommercial thinning has been neglected and the harvesting conditions for industrial wood thinning are difficult. Despite of its positive effects on harvesting costs and on renewable energy potential, whole-tree harvesting has been constantly criticized for causing growth loss. In this paper, the profitability of energy wood thinning was studied in 20 Scots pine-dominated stands where energy wood thinning was carried out. The growth of the stands after thinning was predicted with the help of Motti-stand simulator. Entire rotation time of the stands was simulated with different management alternatives. The intensity of first thinning and recovery level of logging residues varied between alternatives. In order to attain acceptable harvesting conditions, industrial wood thinning had to be delayed. The effect of energy wood thinning on subsequent stem wood growth was almost the same as in conventional thinning. Whole-tree harvesting for energy proved to be profitable alternative if the stumpage price is around 3EUR m -3 , the interest rate is 3% or 5% and the removal of pulpwood is less than 20 m 3 ha -1 . If the harvestable pulpwood yield is over 20 m 3 ha -1 , integrated harvesting of industrial and energy wood or delayed industrial wood harvesting becomes more profitable. (author)

  5. Impact of timber production and transport costs on stand management

    Science.gov (United States)

    Chris B. LeDoux; Chris B. LeDoux

    1988-01-01

    Evaluates the impact of cable logging technology, transportation network standards, and transport vehicles on stand management. Managers can use results to understand the impact of timber production costs on eastern hardwood management.

  6. Stand quality management in a late-rotation, red oak-sweetgum stand in east Mississippi: preliminary results following thinning

    Science.gov (United States)

    James S. Meadows; Daniel A. Skojac

    2012-01-01

    Stand quality management is a new management strategy in which thinning prescriptions are based solely on tree quality rather than a quantitative level of residual stand density. As long as residual density falls within fairly broad limits, prescriptions are based on tree quality alone. We applied four thinning prescriptions based on stand quality management, along...

  7. StandsSIM-MD: a Management Driven forest SIMulator

    Energy Technology Data Exchange (ETDEWEB)

    Barreiro, S.; Rua, J.; Tomé, M.

    2016-07-01

    Aim of the study. The existing stand level forest simulators available in Portugal were not developed with the aim of including up-to-date model versions and were limited in terms of accounting for forest management. The simulators’ platform, sIMfLOR was recently created to implement different growth models with a common philosophy. The objective was developing one easily-updatable, user-friendly, forest management and climate change sensitive simulator capable of projecting growth for the main tree species in Portugal. Area of the study: Portugal. Material and methods: The new simulator was programmed in a modular form consisting of several modules. The growth module integrates different forest growth and yield models (empirical and process-based) for the main wood production tree species in Portugal (eucalypt, umbrella and maritime pines); whereas the management module drives the growth projections along the planning horizon according to a range of forest management approaches and climate (at present only available for eucalypt). Main results: The main result is the StandsSIM-MD Management Driven simulator that overcomes the limitations of the existing stand level simulators. It is a step forward when compared to the models currently available in the sIMfLOR platform covering more tree species, stand structures and stand compositions. It is focused on end-users and it is based on similar concepts regarding the generation of required inputs and generated outputs. Research highlights: Forest Management Driven simulations approach. Multiple Prescriptions-Per-Stand functionality. StandsSIM-MD can be used to support landowners decisions on stand forest management. StandsSIM-MD simulations at regional level can be combined with optimization routines. (Author)

  8. StandsSIM-MD: a Management Driven forest SIMulator

    Directory of Open Access Journals (Sweden)

    Susana Barreiro

    2016-07-01

    Full Text Available Aim of the study: The existing stand level forest simulators available in Portugal were not developed with the aim of including up-to-date model versions and were limited in terms of accounting for forest management. The simulators’ platform, sIMfLOR was recently created to implement different growth models with a common philosophy. The objective was developing one easily-updatable, user-friendly, forest management and climate change sensitive simulator capable of projecting growth for the main tree species in Portugal. Area of the study: Portugal. Material and methods: The new simulator was programmed in a modular form consisting of several modules. The growth module integrates different forest growth and yield models (empirical and process-based for the main wood production tree species in Portugal (eucalypt, umbrella and maritime pines; whereas the management module drives the growth projections along the planning horizon according to a range of forest management approaches and climate (at present only available for eucalypt. Main results: The main result is the StandsSIM-MD Management Driven simulator that overcomes the limitations of the existing stand level simulators. It is a step forward when compared to the models currently available in the sIMfLOR platform covering more tree species, stand structures and stand compositions. It is focused on end-users and it is based on similar concepts regarding the generation of required inputs and generated outputs. Research highlights: -          Forest Management Driven simulations approach -          Multiple Prescriptions-Per-Stand functionality -          StandsSIM-MD can be used to support landowners decisions on stand forest management -          StandsSIM-MD simulations at regional level can be combined with optimization routines Keywords: Forest simulator, Forest Management Approaches; StandsSIM-MD; forest management.

  9. Stand development and yields of Appalachian hardwood stands managed with single-tree selection for at least 30 years

    Science.gov (United States)

    Neil I Lamson; H. Clay Smith; H. Clay Smith

    1991-01-01

    Appalachian hardwood stands in West Virginia were managed for 30 or more years using single-tree selection regeneration practices. Stand yield data suggest that current stand growth will provide economical harvest cuts for several future cutting cycles. This case study indicates that the single-tree selection practice has potential for landowners who want to maintain...

  10. Optimal Stand Management: Traditional and Neotraditional Solutions

    Science.gov (United States)

    Karen Lee Abt; Jeffrey P. Prestemon

    2003-01-01

    The traditional Faustmann (1849) model has served as the foundation of economic theory of the firm for the forestry production process. Since its introduction over 150 years ago, many variations of the Faustmann have been developed which relax certain assumptions of the traditional model, including constant prices, risk neutrality, zero production and management costs...

  11. Management of black Locust (Robinia pseudoacacia L.) stands in Hungary

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Black locust (Robinia pseudoacacia L.) was the first forest tree species to be imported from North America to Europe at the beginning of the 17th century. It is the most important fast-growing stand-forming tree species in Hungary . Black locust plantations can be successfully established in response to arange of economic and ecological opportunities. Plantation survival and productivity are maximized by matching the species' growth characteristics with silvicultura l options and land management needs. In the paper the sequence of forest tending operations in black locust stands is proposed, based on results of long-term st and structure and forest yield trials. Implementing good silvicultural plans and models will lead to profitable black locust stands and greater acceptance of the species by land managers. Black locust would also beavery useful species for energy productions as the related research results have been shown in the paper .

  12. Stand Alone Battery Thermal Management System

    Energy Technology Data Exchange (ETDEWEB)

    Brodie, Brad [Denso International America, Incorporated, Southfield, MI (United States)

    2015-09-30

    The objective of this project is research, development and demonstration of innovative thermal management concepts that reduce the cell or battery weight, complexity (component count) and/or cost by at least 20%. The project addresses two issues that are common problems with current state of the art lithium ion battery packs used in vehicles; low power at cold temperatures and reduced battery life when exposed to high temperatures. Typically, battery packs are “oversized” to satisfy the two issues mentioned above. The first phase of the project was spent making a battery pack simulation model using AMEsim software. The battery pack used as a benchmark was from the Fiat 500EV. FCA and NREL provided vehicle data and cell data that allowed an accurate model to be created that matched the electrical and thermal characteristics of the actual battery pack. The second phase involved using the battery model from the first phase and evaluate different thermal management concepts. In the end, a gas injection heat pump system was chosen as the dedicated thermal system to both heat and cool the battery pack. Based on the simulation model. The heat pump system could use 50% less energy to heat the battery pack in -20°C ambient conditions, and by keeping the battery cooler at hot climates, the battery pack size could be reduced by 5% and still meet the warranty requirements. During the final phase, the actual battery pack and heat pump system were installed in a test bench at DENSO to validate the simulation results. Also during this phase, the system was moved to NREL where testing was also done to validate the results. In conclusion, the heat pump system can improve “fuel economy” (for electric vehicle) by 12% average in cold climates. Also, the battery pack size, or capacity, could be reduced 5%, or if pack size is kept constant, the pack life could be increased by two years. Finally, the total battery pack and thermal system cost could be reduced 5% only if the

  13. Stand quality management of a water oak plantation in Louisiana: preliminary results following thinning

    Science.gov (United States)

    James S. Meadows; Daniel A., Jr. Skojac

    2010-01-01

    Stand quality management is a new guiding principle in which thinning prescriptions are based on tree quality rather than on residual stand density. We recently initiated a series of hardwood thinning studies to determine the effects of four stand quality management thinning prescriptions on both stand-level and individual-tree-level growth, quality, and value: (1) no...

  14. A method of forest management for the planned introduction of intensive husbandry in virgin forest stands

    Science.gov (United States)

    B. Dolezal

    1978-01-01

    The method proposed is derived from long experience of intensive management in forest stands of Central Europe and from our proposal for management in virgin Iranian forests of the Caspian Region. The method establishes the need for systematic planning of stand conversion to insure both sustained yield and the harvesting of sufficient timber to sustain economic...

  15. Functional groups show distinct differences in nitrogen cycling during early stand development: implications for forest management

    Science.gov (United States)

    Doug P. Aubrey; David R. Coyle; Mark D. Coleman

    2012-01-01

    Background and aims Nutrient acquisition of forest stands is controlled by soil resource availability and belowground production, but tree species are rarely compared in this regard. Here, we examine ecological and management implications of nitrogen (N) dynamics during early forest stand development in productive commercial tree species with narrow (Populus...

  16. Management of spruce-fir in even-aged stands in the central Rocky Mountains

    Science.gov (United States)

    Robert R. Alexander; Carleton B. Edminster

    1980-01-01

    Potential production of Engelmann spruce and subalpine fir in the central Rocky Mountains is simulated for vario.us combinations of stand density, site quality, ages, and thinning schedules. Such estimates are needed to project future development of stands managed in different ways for various uses.

  17. Managing Appalachian hardwood stands using four regeneration practices--34 year results

    Science.gov (United States)

    H. Clay Smith; Gary W. Miller

    1987-01-01

    Adjacent Appalachian hardwood stands in West Virginia established on excellent growing sites were managed for a 34-year period using four regeneration practices. These practices included a commercial clearcut, 15.5-in diameter-limit, and two single-tree selection practices. An uncut area was maintained as a control. Stand development, growth response, and some stumpage...

  18. Abundance of juvenile eastern box turtles in manages forest stands

    Science.gov (United States)

    Z. Felix; Y. Wang; H. Czech; C. Schweitzer

    2008-01-01

    Between 2002 and 2005, we used drift fences and artificial pools to sample juvenile eastern box turtles (Terrapene carolina) in northeastern Alabama in forest stands experimentally treated to retain various amounts of overstory trees—clear-cuts and those with 25%–50% and 75%–100% of trees retained.We captured juvenile turtles only in clear-cut and 25%–50% retention...

  19. Fire in longleaf pine stand management: an economic analysis

    Science.gov (United States)

    Rodney L. Busby; Donald G. Hodges

    1999-01-01

    A simulation analysis of the economics of using prescribed fire as a forest management tool in the management of longleaf pine (Pinus palustris Mill.) plantations was conducted. A management regime using frequent prescribed fire was compared to management regimes involving fertilization and chemical release, chemical control, and mechanical control. Determining the...

  20. Managing black walnut in natural stands: the human dimension

    Science.gov (United States)

    H.E. " Hank" Stelzer

    2004-01-01

    In managing black walnut, or any forest tree species, the human dimension is often overlooked. As a result, both the number of landowners managing their land and the number of forested acres under management has not significantly increased over the past 30 years. Elements of the human landscape are explored and a roadmap for engaging landowners is proposed.

  1. Management system certification benefits: where do we stand?

    International Nuclear Information System (INIS)

    Fonseca, Luis Miguel Ciravegna Martins da; Domingues, José Pedro; Machado, Pilar Baylina; Calderón, Mario

    2017-01-01

    The implementation and certification of Management Systems International Standards, such as ISO 9001 and ISO 14001, achieved a high international recognition, with more than 1 million organizations with their Quality Management Systems certified worldwide. Researchers have been paying considerable attention to this theme and the number of published articles has robustly grown. Although on an overall basis, the research results support the existence of positive impacts on the adoption and certification of these International Standards, there are various inconsistencies and contradictory results, leading to some controversy over its impacts for organizations. This study aims to bring a longitudinal time perspective to this area of research, analyzing the articles published since 1996, on the benefits of Management Systems Certification. A longitudinal perspective of countries of authors origin, keywords and journals is presented, complemented with an evaluation of the research results. Design/methodology/approach: A Bibliometric Study supported the research, with data collected from Web of Science, SCOPUS, and Research Gate data bases. Following the detailed analysis of the journal titles, articles abstracts and their full content, an evaluation scale was adopted to assess if the results support the existence of a positive relationship between Management System Certification and economic, financial or stakeholder results. Findings: The results evidence a steep increase in the number of publications addressing Management Systems Certification benefits, that mainly originate from Europe (48%) and East Asia and Pacific (23%), with Spain as the leading country (accounting for 14% of the total number of articles published between 1996 and April 2017). Journal of Cleaner Production (Environmental Management System Certification) and Total Quality Management and Business Excellence journal (Quality Management Systems Certification) are the leading journals for disseminating

  2. Management system certification benefits: where do we stand?

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, Luis Miguel Ciravegna Martins da; Domingues, José Pedro; Machado, Pilar Baylina; Calderón, Mario

    2017-07-01

    The implementation and certification of Management Systems International Standards, such as ISO 9001 and ISO 14001, achieved a high international recognition, with more than 1 million organizations with their Quality Management Systems certified worldwide. Researchers have been paying considerable attention to this theme and the number of published articles has robustly grown. Although on an overall basis, the research results support the existence of positive impacts on the adoption and certification of these International Standards, there are various inconsistencies and contradictory results, leading to some controversy over its impacts for organizations. This study aims to bring a longitudinal time perspective to this area of research, analyzing the articles published since 1996, on the benefits of Management Systems Certification. A longitudinal perspective of countries of authors origin, keywords and journals is presented, complemented with an evaluation of the research results. Design/methodology/approach: A Bibliometric Study supported the research, with data collected from Web of Science, SCOPUS, and Research Gate data bases. Following the detailed analysis of the journal titles, articles abstracts and their full content, an evaluation scale was adopted to assess if the results support the existence of a positive relationship between Management System Certification and economic, financial or stakeholder results. Findings: The results evidence a steep increase in the number of publications addressing Management Systems Certification benefits, that mainly originate from Europe (48%) and East Asia and Pacific (23%), with Spain as the leading country (accounting for 14% of the total number of articles published between 1996 and April 2017). Journal of Cleaner Production (Environmental Management System Certification) and Total Quality Management and Business Excellence journal (Quality Management Systems Certification) are the leading journals for disseminating

  3. Management system certification benefits: where do we stand?

    Directory of Open Access Journals (Sweden)

    Luis Miguel Ciravegna Martins da Fonseca

    2017-09-01

    Full Text Available Purpose: The implementation and certification of Management Systems International Standards, such as ISO 9001 and ISO 14001, achieved a high international recognition, with more than 1 million organizations with their Quality Management Systems certified worldwide. Researchers have been paying considerable attention to this theme and the number of published articles has robustly growth. Although, on an overall basis, the research results support the existence of positive impacts on the use and certification of these International Standards, there are various inconsistency and contradictory results, leading to some controversy over its impacts for organizations. This study aims to bring a longitudinal time perspective to this area of research, analyzing the articles published since 1996, on the benefits of Management Systems Certification. A longitudinal perspective of countries of authors origin, keywords and journals is presented, complemented with an evaluation of the research results. Design/methodology/approach: The research was supported with a Bibliometric Study, with data collected from Web of Science, SCOPUS, and Research Gate data bases. Following the detailed analysis of the journal titles, articles abstracts and their full content, an evaluation scale was applied to access if the results support the existence of a positive relationship between MSC and economic, financial or stakeholder results. Findings: The results evidence a steep increase in the number of publications addressing Management Systems Certification benefits, that mainly originate from Europe (48% and East Asia and Pacific (23%, with Spain as the clear leading country accounting (43% of the total number of articles published between 1996 and April 2017. Journal of Cleaner Production (EMSC and Total Quality Management and Business Excellence journal (QMSC are the leading journals for disseminating the research and the most used keywords are “Quality/Environment”,

  4. Richness of lichen species, especially of threatened ones, is promoted by management methods furthering stand continuity.

    Directory of Open Access Journals (Sweden)

    Steffen Boch

    Full Text Available Lichens are a key component of forest biodiversity. However, a comprehensive study analyzing lichen species richness in relation to several management types, extending over different regions and forest stages and including information on site conditions is missing for temperate European forests. In three German regions (Schwäbische Alb, Hainich-Dün, Schorfheide-Chorin, the so-called Biodiversity Exploratories, we studied lichen species richness in 631 forest plots of 400 m(2 comprising different management types (unmanaged, selection cutting, deciduous and coniferous age-class forests resulting from clear cutting or shelterwood logging, various stand ages, and site conditions, typical for large parts of temperate Europe. We analyzed how lichen species richness responds to management and habitat variables (standing biomass, cover of deadwood, cover of rocks. We found strong regional differences with highest lichen species richness in the Schwäbische Alb, probably driven by regional differences in former air pollution, and in precipitation and habitat variables. Overall, unmanaged forests harbored 22% more threatened lichen species than managed age-class forests. In general, total, corticolous, and threatened lichen species richness did not differ among management types of deciduous forests. However, in the Schwäbische-Alb region, deciduous forests had 61% more lichen species than coniferous forests and they had 279% more threatened and 76% more corticolous lichen species. Old deciduous age classes were richer in corticolous lichen species than young ones, while old coniferous age-classes were poorer than young ones. Overall, our findings highlight the importance of stand continuity for conservation. To increase total and threatened lichen species richness we suggest (1 conserving unmanaged forests, (2 promoting silvicultural methods assuring stand continuity, (3 conserving old trees in managed forests, (4 promoting stands of native deciduous

  5. Richness of Lichen Species, Especially of Threatened Ones, Is Promoted by Management Methods Furthering Stand Continuity

    Science.gov (United States)

    Boch, Steffen; Prati, Daniel; Hessenmöller, Dominik; Schulze, Ernst-Detlef; Fischer, Markus

    2013-01-01

    Lichens are a key component of forest biodiversity. However, a comprehensive study analyzing lichen species richness in relation to several management types, extending over different regions and forest stages and including information on site conditions is missing for temperate European forests. In three German regions (Schwäbische Alb, Hainich-Dün, Schorfheide-Chorin), the so-called Biodiversity Exploratories, we studied lichen species richness in 631 forest plots of 400 m2 comprising different management types (unmanaged, selection cutting, deciduous and coniferous age-class forests resulting from clear cutting or shelterwood logging), various stand ages, and site conditions, typical for large parts of temperate Europe. We analyzed how lichen species richness responds to management and habitat variables (standing biomass, cover of deadwood, cover of rocks). We found strong regional differences with highest lichen species richness in the Schwäbische Alb, probably driven by regional differences in former air pollution, and in precipitation and habitat variables. Overall, unmanaged forests harbored 22% more threatened lichen species than managed age-class forests. In general, total, corticolous, and threatened lichen species richness did not differ among management types of deciduous forests. However, in the Schwäbische-Alb region, deciduous forests had 61% more lichen species than coniferous forests and they had 279% more threatened and 76% more corticolous lichen species. Old deciduous age classes were richer in corticolous lichen species than young ones, while old coniferous age-classes were poorer than young ones. Overall, our findings highlight the importance of stand continuity for conservation. To increase total and threatened lichen species richness we suggest (1) conserving unmanaged forests, (2) promoting silvicultural methods assuring stand continuity, (3) conserving old trees in managed forests, (4) promoting stands of native deciduous tree species

  6. Assessment of Stand-Alone Displays for Time Management in a Creativity-Driven Learning Environment

    DEFF Research Database (Denmark)

    Frimodt-Møller, Søren

    2017-01-01

    This paper considers the pros and cons of stand-alone displays, analog (e.g. billboards, blackboards, whiteboards, large pieces of paper etc.) as well as digital (e.g. large shared screens, digital whiteboards or similar), as tools for time management processes in a creativity-driven learning...

  7. Spatial analysis of longleaf pine stand dynamics after 60 years of management

    Science.gov (United States)

    John C. Gilbert; John S. Kush; Rebecca J. Barlow

    2012-01-01

    There are still many questions and misconceptions about the stand dynamics of naturally-regenerated longleaf pine (Pinus palustris Mill.). Since 1948, the “Farm Forty,” a forty-acre tract located on the USDA Forest Service Escambia Experimental Forest near Brewton, Alabama, has been managed to create high quality wood products, to successfully...

  8. Silvicultural Considerations in Managing Southern Pine Stands in the Context of Southern Pine Beetle

    Science.gov (United States)

    James M. Guldin

    2011-01-01

    Roughly 30 percent of the 200 million acres of forest land in the South supports stands dominated by southern pines. These are among the most productive forests in the nation. Adapted to disturbance, southern pines are relatively easy to manage with even-aged methods such as clearcutting and planting, or the seed tree and shelterwood methods with natural regeneration....

  9. The Colville Study: wood utilization for ecosystem management: preliminary results of study of product potential from small-diameter stands.

    Science.gov (United States)

    S. Willits; R. J. Barbour; J. McNeel; R. D. Fight; G. C. Myers; A. Mason

    The Colville Study was developed in 1994 to identify and evaluate a series of management options for achieving ecosystem objectives in dense stands of small-diameter trees while also producing wood products. The Colville National Forest selected the Rocky II Timber Sale as an example of this type of stand that needed management to achieve the following goals: (1)...

  10. Changes of forest stands vulnerability to future wind damage resulting from different management methods

    DEFF Research Database (Denmark)

    Panferov, O.; Sogachev, Andrey; Ahrends, B.

    2010-01-01

    The structure of forests stands changes continuously as a result of forest growth and both natural and anthropogenic disturbances like windthrow or management activities – planting/cutting of trees. These structure changes can stabilize or destabilize forest stands in terms of their resistance...... to wind damage. The driving force behind the damage is the climate, but the magnitude and sign of resulting effect depend on tree species, management method and soil conditions. The projected increasing frequency of weather extremes in the whole and severe storms in particular might produce wide area...... damage in European forest ecosystems during the 21st century. To assess the possible wind damage and stabilization/destabilization effects of forest management a number of numeric experiments are carried out for the region of Solling, Germany. The coupled small-scale process-based model combining Brook90...

  11. Information systems for the materials management department: stand-alone and enterprise resource planning systems.

    Science.gov (United States)

    2005-03-01

    Materials management information systems (MMISs) incorporate information tools that hospitals can use to automate certain business processes, increase staff compliance with these processes, and identify opportunities for cost savings. Recently, there has been a push by hospital administration to purchase enterprise resource planning (ERP) systems, information systems that promise to integrate many more facets of healthcare business. We offer this article to help materials managers, administrators, and others involved with information system selection understand the changes that have taken place in materials management information systems, decide whether they need a new system and, if so, whether a stand-alone MMIS or an ERP system will be the best choice.

  12. Integrated System Health Management: Pilot Operational Implementation in a Rocket Engine Test Stand

    Science.gov (United States)

    Figueroa, Fernando; Schmalzel, John L.; Morris, Jonathan A.; Turowski, Mark P.; Franzl, Richard

    2010-01-01

    This paper describes a credible implementation of integrated system health management (ISHM) capability, as a pilot operational system. Important core elements that make possible fielding and evolution of ISHM capability have been validated in a rocket engine test stand, encompassing all phases of operation: stand-by, pre-test, test, and post-test. The core elements include an architecture (hardware/software) for ISHM, gateways for streaming real-time data from the data acquisition system into the ISHM system, automated configuration management employing transducer electronic data sheets (TEDS?s) adhering to the IEEE 1451.4 Standard for Smart Sensors and Actuators, broadcasting and capture of sensor measurements and health information adhering to the IEEE 1451.1 Standard for Smart Sensors and Actuators, user interfaces for management of redlines/bluelines, and establishment of a health assessment database system (HADS) and browser for extensive post-test analysis. The ISHM system was installed in the Test Control Room, where test operators were exposed to the capability. All functionalities of the pilot implementation were validated during testing and in post-test data streaming through the ISHM system. The implementation enabled significant improvements in awareness about the status of the test stand, and events and their causes/consequences. The architecture and software elements embody a systems engineering, knowledge-based approach; in conjunction with object-oriented environments. These qualities are permitting systematic augmentation of the capability and scaling to encompass other subsystems.

  13. Incorporating stand level risk management options into forest decision support systems

    Directory of Open Access Journals (Sweden)

    Kyle Eyvindson

    2018-01-01

    Full Text Available Aim of study: To examine methods of incorporating risk and uncertainty to stand level forest decisions. Area of study: A case study examines a small forest holding from Jönköping, Sweden. Material and methods: We incorporate empirically estimated uncertainty into the simulation through a Monte Carlo approach when simulating the forest stands for the next 100 years. For the iterations of the Monte Carlo approach, errors were incorporated into the input data which was simulated according to the Heureka decision support system. Both the Value at Risk and the Conditional Value at Risk of the net present value are evaluated for each simulated stand. Main results: Visual representation of the errors can be used to highlight which decision would be most beneficial dependent on the decision maker’s opinion of the forest inventory results. At a stand level, risk preferences can be rather easily incorporated into the current forest decision support software. Research highlights: Forest management operates under uncertainty and risk. Methods are available to describe this risk in an understandable fashion for the decision maker.

  14. Traditional silvopastoral management and its effects on forest stand structure in northern Zagros, Iran

    DEFF Research Database (Denmark)

    Valipour, Ahmad; Plieninger, Tobias; Shakeri, Zahed

    2014-01-01

    and to investigate the effects of these practices on forest stand structure. To understand how the traditional forest management system works, empirical survey methods, in particular face to face interviews and participation in traditional practices have been employed. In general, local livelihoods depend on three......Oak forests of Iran are managed for soil conservation, water quality and other non-market ecosystem services. Nationalization policies in 1963 implied shifts from private ownership and informal traditional management to public ownership and state forest management. In spite of the nationalization......, informal practices and conventional ownership have been continued which has caused considerable conflicts between local people and the state forest administration. The aim of the study was to systematically gather the components of traditional silvopastoral management in these oak forests...

  15. Red Alder-Conifer Stands in Alaska: An Example of Mixed Species Management to Enhance Structural and Biological Complexity

    Directory of Open Access Journals (Sweden)

    Robert L. Deal

    2017-04-01

    Full Text Available There is worldwide interest in managing forests to improve biodiversity, enhance ecosystem services and assure long-term sustainability of forest resources. An increasingly important goal of forest management is to increase stand diversity and improve wildlife and aquatic habitat. Well-planned silvicultural systems containing a mixture of broadleaf-conifer species have potential to enhance stand diversity and provide other ecosystem services earlier than typical even-aged conifer plantations. Here, we use the example of mixed Sitka spruce/western hemlock and red alder in young, managed stands in southeast Alaska to achieve these goals. We briefly describe the silvics of Sitka spruce, western hemlock and red alder plantations as pure conifer stands or pure broadleaf stands. Then, we synthesize studies of mixed red alder-Sitka spruce/western hemlock stands in southeast Alaska and present their potential for improving stand structural complexity, biodiversity and other ecosystem services over pure conifer forests. Finally, we discuss some of the opportunities and potential tradeoffs for managing mixed broadleaf-conifer stands for providing a number of natural resources and the influence of these broadleaf-conifer forests on ecosystem linkages and processes.

  16. Robust Power Management Control for Stand-Alone Hybrid Power Generation System

    International Nuclear Information System (INIS)

    Kamal, Elkhatib; Adouane, Lounis; Aitouche, Abdel; Mohammed, Walaa

    2017-01-01

    This paper presents a new robust fuzzy control of energy management strategy for the stand-alone hybrid power systems. It consists of two levels named centralized fuzzy supervisory control which generates the power references for each decentralized robust fuzzy control. Hybrid power systems comprises: a photovoltaic panel and wind turbine as renewable sources, a micro turbine generator and a battery storage system. The proposed control strategy is able to satisfy the load requirements based on a fuzzy supervisor controller and manage power flows between the different energy sources and the storage unit by respecting the state of charge and the variation of wind speed and irradiance. Centralized controller is designed based on If-Then fuzzy rules to manage and optimize the hybrid power system production by generating the reference power for photovoltaic panel and wind turbine. Decentralized controller is based on the Takagi-Sugeno fuzzy model and permits us to stabilize each photovoltaic panel and wind turbine in presence of disturbances and parametric uncertainties and to optimize the tracking reference which is given by the centralized controller level. The sufficient conditions stability are formulated in the format of linear matrix inequalities using the Lyapunov stability theory. The effectiveness of the proposed Strategy is finally demonstrated through a SAHPS (stand-alone hybrid power systems) to illustrate the effectiveness of the overall proposed method. (paper)

  17. Stand-Alone Photovoltaic System Operation with Energy Management and Fault Tolerant

    International Nuclear Information System (INIS)

    Jmashidpour, Ehsan; Poure, Philippe; Gholipour, E.; Saadate, Shahrokh

    2017-01-01

    This paper presents a stand-alone photovoltaic (PV) system with a fault tolerant operation capability. An energy management method is provided to keep the balance between produced and consumed energy instantaneously. As the storage element, an Ultra-Capacitor (UC) pack is used for facing high frequency variation of the load/source, and batteries are in charge of slow load /source variations. A Maximum Power Point Tracking (MPPT) algorithm is applied to control the boost converter of the PV source to achieve the maximum power. In order to improve the micro-grid service continuity and reliability, a fast fault diagnosis method based on the converter current shape for PV source is applied. Finally, the validity of the proposed energy management and the fault diagnosis method is confirmed by the simulation and experimental results. (author)

  18. Energy management system for stand-alone diesel-wind-biomass microgrid with energy storage system

    International Nuclear Information System (INIS)

    Wang, Chengshan; Liu, Yixin; Li, Xialin; Guo, Li; Qiao, Lei; Lu, Hai

    2016-01-01

    An energy management system for stand-alone microgrid composed of diesel generators, wind turbine generator, biomass generator and an ESS (energy storage system) is proposed in this paper. Different operation objectives are achieved by a hierarchical control structure with different time scales. Firstly, the optimal schedules of the diesel generators, wind turbine generator, biomass generator and ESS are determined fifteen minutes ahead according to the super short-term forecast of load and wind speed in the optimal scheduling layer. Comprehensive analysis which takes the uncertainty of load and wind speed into account is conducted in this layer to minimize the operation cost of the system and ensure a desirable range of the state of charge of the ESS. Secondly, the operation points of each unit are regulated dynamically to guarantee real-time power balance and safety range of diesel generation in the real-time control layer, based on which the response capability when suffering significant forecast deviation and other emergency issues, e.g. sudden load-up can be improved. Finally, the effectiveness of the proposed energy management strategy is verified on an RT-Lab based real-time simulation platform, and the economic performances with different types of ESS are analyzed as well. - Highlights: • A hierarchical control strategy is proposed for a stand-alone microgrid. • The uncertainties of load and wind speed have been considered. • Better economic performance and high reliability of the system can be achieved. • The influences of different energy storage systems have been analyzed.

  19. Comparison of three sampling methods in the characterization of cork oak stands for management purpose

    NARCIS (Netherlands)

    Paulo, M.J.; Tomé, M.; Otten, A.; Stein, A.

    2005-01-01

    The cork oak (Quercus suber L.) is an evergreen oak that has the ability to produce a continuous layer of cork tissue which regenerates after being removed. Cork oak stands can be diverse in structure. Young stands are often regularly spaced, whereas older stands usually show clustering and can be

  20. Tree microhabitat structures as indicators of biodiversity in Douglas-fir forests of different stand ages and management histories in the Pacific Northwest, U.S.A.

    Science.gov (United States)

    Alexa K. Michel; Susanne. Winter

    2009-01-01

    In this study, microhabitat structures in Douglas-fir (Pseudotsuga menziesii) forests were defined and their frequency and abundance in natural stands and stands of varying active management histories and stand ages was compared. Indicator microhabitat structures for natural forests were determined and the relationship of the abundance of...

  1. Integrated System Health Management (ISHM) for Test Stand and J-2X Engine: Core Implementation

    Science.gov (United States)

    Figueroa, Jorge F.; Schmalzel, John L.; Aguilar, Robert; Shwabacher, Mark; Morris, Jon

    2008-01-01

    ISHM capability enables a system to detect anomalies, determine causes and effects, predict future anomalies, and provides an integrated awareness of the health of the system to users (operators, customers, management, etc.). NASA Stennis Space Center, NASA Ames Research Center, and Pratt & Whitney Rocketdyne have implemented a core ISHM capability that encompasses the A1 Test Stand and the J-2X Engine. The implementation incorporates all aspects of ISHM; from anomaly detection (e.g. leaks) to root-cause-analysis based on failure mode and effects analysis (FMEA), to a user interface for an integrated visualization of the health of the system (Test Stand and Engine). The implementation provides a low functional capability level (FCL) in that it is populated with few algorithms and approaches for anomaly detection, and root-cause trees from a limited FMEA effort. However, it is a demonstration of a credible ISHM capability, and it is inherently designed for continuous and systematic augmentation of the capability. The ISHM capability is grounded on an integrating software environment used to create an ISHM model of the system. The ISHM model follows an object-oriented approach: includes all elements of the system (from schematics) and provides for compartmentalized storage of information associated with each element. For instance, a sensor object contains a transducer electronic data sheet (TEDS) with information that might be used by algorithms and approaches for anomaly detection, diagnostics, etc. Similarly, a component, such as a tank, contains a Component Electronic Data Sheet (CEDS). Each element also includes a Health Electronic Data Sheet (HEDS) that contains health-related information such as anomalies and health state. Some practical aspects of the implementation include: (1) near real-time data flow from the test stand data acquisition system through the ISHM model, for near real-time detection of anomalies and diagnostics, (2) insertion of the J-2X

  2. Determining Nutrient Requirements For Intensively Managed Loblolly Pine Stands Using the SSAND (Soil Supply and Nutrient Demand) Model

    Science.gov (United States)

    Hector G. Adegbidi; Nicholas B. Comerford; Hua Li; Eric J. Jokela; Nairam F. Barros

    2002-01-01

    Nutrient management represents a central component of intensive silvicultural systems that are designed to increase forest productivity in southern pine stands. Forest soils throughout the South are generally infertile, and fertilizers may be applied one or more times over the course of a rotation. Diagnostic techniques, such as foliar analysis and soil testing are...

  3. Synthesis of regional wildlife and vegetation field studies to guide management of standing and down dead trees

    Science.gov (United States)

    Bruce G. Marcot; Janet L. Ohmann; Kim L. Mellen-McLean; Karen L. Waddell

    2010-01-01

    We used novel methods for combining information from wildlife and vegetation field studies to develop guidelines for managing dead wood for wildlife and biodiversity. The DecAID Decayed Wood Adviser presents data on wildlife use of standing and down dead trees (snags and down wood) and summaries of regional vegetation plot data depicting dead wood conditions, for...

  4. A new method for evaluating forest thinning: growth dominance in managed Pinus resinosa stands

    Science.gov (United States)

    John B. Bradford; Anthony W. D' Amato; Brian J. Palik; Shawn. Fraver

    2010-01-01

    Growth dominance is a relatively new, simple, quantitative metric of within-stand individual tree growth patterns, and is defined as positive when larger trees in the stand display proportionally greater growth than smaller trees, and negative when smaller trees display proportionally greater growth than larger trees. We examined long-term silvicultural experiments in...

  5. Stand-alone excitation synchronous wind power generators with power flow management strategy

    Directory of Open Access Journals (Sweden)

    Tzuen-Lih Chern

    2014-09-01

    Full Text Available This study presents a stand-alone excitation synchronous wind power generator (SESWPG with power flow management strategy (PFMS. The rotor speed of the excitation synchronous generator tracks the utility grid frequency by using servo motor tracking technologies. The automatic voltage regulator governs the exciting current of generator to achieve the control goals of stable voltage. When wind power is less than the needs of the consumptive loading, the proposed PFMS increases motor torque to provide a positive power output for the loads, while keeping the generator speed constant. Conversely, during the periods of wind power greater than output loads, the redundant power of generator production is charged to the battery pack and the motor speed remains constant with very low power consumption. The advantage of the proposed SESWPG is that the generator can directly output stable alternating current (AC electricity without using additional DC–AC converters. The operation principles with software simulation for the system are described in detail. Experimental results of a laboratory prototype are shown to verify the feasibility of the system.

  6. Management of young forest stands for integrated production of wood fuel and quality timber. Final report

    International Nuclear Information System (INIS)

    Lundmark, Tomas; Sahlen, Kenneth; Ulvcrona, Kristina

    2005-06-01

    The aim of this project has been to develop practical silvicultural measures that integrate the optimization of biomass production in dense young mixed stands with production of quality timber later during the rotation period. The results show that annual biomass production can be trippled by keeping young stands dense and adding fertilizers. At the same time by delaying the time for pre-commercial thinning (or replacing it with a biomass harvest) relative branch size in the lower part of the stem will be reduced. This support the hypothesis that biomass production can be improved if young stands are kept dense up to the height of 8-10 m and as a consequence of delayed thinning timber quality can also be improved. Important background data for technical development has also been provided as well as data needed for economical analyses of different silvicultural systems including the treatment of heterogenous dense stands with mixed species composition

  7. Sizing, techno-economic and generation management analysis of a stand alone photovoltaic power unit including storage devices

    International Nuclear Information System (INIS)

    Jallouli, Rihab; Krichen, Lotfi

    2012-01-01

    Due to the mismatch between the load demand and the intermittent solar energy, a stand-alone photovoltaic-hydrogen system and an optimal control scheme are designed to maintain the high system efficiency. Based on meteorological and the load demand data, a system sizing technique is proposed to establish the minimum capacity of the system components, which are a photovoltaic (PV) panel, a proton exchange membrane fuel cell (PEMFC), a battery bank and an alkaline electrolyzer (Elz). An accurate energy management scheme that is utilized during power transfer is proposed to meet the economic requirements. Case studies are used to verify the efficiency of the energy management strategy and system sizing technique. Simulation results illustrate a simple solution to the design and processing of stand-alone PV-hydrogen (PV-H 2 ) systems. -- Highlights: ► We study a stand alone PV-hydrogen system comprising renewable devices. ► A PV generator, a battery bank, a fuel cell and an electrolyzer are modeled. ► Power management taking into account the economic arrangement and the operating conditions to ensure energy availability is proposed.

  8. Soil microbial activity in Aleppo pine stands naturally regenerated after fire: silvicultural management and induced drought

    Directory of Open Access Journals (Sweden)

    D. Moya

    2013-01-01

    Full Text Available In post-fire restoration, early monitoring is mandatory to check impacts and ecosystem responses to apply proper management according to social standards and ecological conditions. In areas where the natural regeneration was successful, excessive tree density can be found which induces to high intraspecific competence and assisted restoration management could be adequate. In addition, climatic changes will have large impacts on vegetation productivity and resilience since the regional models for south-eastern Spain predicts a rainfall decrease of about 20% and temperature increase of 4.5 ºC. The microbial biomass could be used as indicator of ecosystem recovery, since it is negatively affected by wildfires and depends on fire characteristics, vegetation and soil properties. Our aim is to determine how forest management may affect the ecosystem recovery in different climatic scenarios, included drought scenarios with and without forest management (thinning.We compared soil physicochemical properties and microbial activity in four scenarios: unmanaged and thinned stands in two rainfall scenarios (under induced drought. The study areas were set close to Yeste (Albacete where Aleppo pine forest were burned in summer 1994 (nearly 14000 ha. We set sixteen rectangular plots (150 m2; 15 m ×10 m implementing experimental silvicultural treatments: thinning eight plots in 2004, reducing the naturally recovered tree density from about 12000 to 1600 pine trees ha-1. In addition, in half the plots, we induced drought conditions from about 500 to 400 mm (20% from March 2009. In every plot, we monitored temperature at ground level (Ts, 10 cm depth (T10d and soil relative humidity (RH. Taking into account season of the year and canopy coverage, we collected soil samples in mid-winter (ending January 2011 and mid-spring (ending May 2011 under pine trees and in bare soil. The soil samples were used to evaluate soil physicochemical properties and soil microbial

  9. Management of ethical issues related to care of seriously ill dialysis patients in free-standing facilities.

    Science.gov (United States)

    Song, Mi-Kyung; Hanson, Laura C; Gilet, Constance A; Jo, Minjeong; Reed, Teresa J; Hladik, Gerald A

    2014-09-01

    There are few data on the frequency and current management of clinical ethical issues related to care of seriously ill dialysis patients in free-standing dialysis facilities. To examine the extent of clinical ethical challenges experienced by care providers in free-standing facilities and their perceptions about how those issues are managed. A total of 183 care providers recruited from 15 facilities in North Carolina completed a survey regarding the occurrence and management of ethical issues in the past year. Care plan meetings were observed at four of the facilities for three consecutive months. Also, current policies and procedures at each of the facilities were reviewed. The two most frequently experienced challenges involved dialyzing frail patients with multiple comorbidities and caring for disruptive/difficult patients. The most common ways of managing ethical issues were discussions in care plan meetings (n = 47) or discussions with the clinic manager (n = 47). Although policies were in place to guide management of some of the challenges, respondents were often not aware of those policies. Also, although participants reported that ethical issues related to dialyzing undocumented immigrants were fairly common, no facility had a policy for managing this challenge. Participants suggested that all staff obtain training in clinical ethics and communication skills, facilities develop ethics teams, and there be clear policies to guide management of ethical challenges. The scope of ethical challenges was extensive, how these challenges were managed varied widely, and there were limited resources for assistance. Multifaceted efforts, encompassing endeavors at the individual, facility, organization, and national levels, are needed to support staff in improving the management of ethical challenges in dialysis facilities. Copyright © 2014 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

  10. Harvest operations for density management: planning requirements, production, costs, stand damage, and recommendations

    Science.gov (United States)

    Loren D. Kellogg; Stephen J. Pilkerton

    2013-01-01

    Since the early 1990s, several studies have been undertaken to determine the planning requirements, productivity, costs, and residual stand damage of harvest operations in thinning treatments designed to promote development of complex forest structure in order to enhance ecological functioning and biological diversity. Th ese studies include the Oregon State...

  11. An optimized Fuzzy Logic Controller by Water Cycle Algorithm for power management of Stand-alone Hybrid Green Power generation

    International Nuclear Information System (INIS)

    Sarvi, Mohammad; Avanaki, Isa Nasiri

    2015-01-01

    Highlights: • A new method to improve the performance of renewable power management is proposed. • The proposed method is based on Fuzzy Logic optimized by the Water Cycle Algorithm. • The proposed method characteristics are compared with two other methods. • The comparisons confirm that the proposed method is robust and effectiveness one. - Abstract: This paper aims to improve the power management system of a Stand-alone Hybrid Green Power generation based on the Fuzzy Logic Controller optimized by the Water Cycle Algorithm. The proposed Stand-alone Hybrid Green Power consists of wind energy conversion and photovoltaic systems as primary power sources and a battery, fuel cell, and Electrolyzer as energy storage systems. Hydrogen is produced from surplus power generated by the wind energy conversion and photovoltaic systems of Stand-alone Hybrid Green Power and stored in the hydrogen storage tank for fuel cell later using when the power generated by primary sources is lower than load demand. The proposed optimized Fuzzy Logic Controller based power management system determines the power that is generated by fuel cell or use by Electrolyzer. In a hybrid system, operation and maintenance cost and reliability of the system are the important issues that should be considered in studies. In this regard, Water Cycle Algorithm is used to optimize membership functions in order to simultaneously minimize the Loss of Power Supply Probability and operation and maintenance. The results are compared with the particle swarm optimization and the un-optimized Fuzzy Logic Controller power management system to prove that the proposed method is robust and effective. Reduction in Loss of Power Supply Probability and operation and maintenance, are the most advantages of the proposed method. Moreover the level of the State of Charge of the battery in the proposed method is higher than other mentioned methods which leads to increase battery lifetime.

  12. Hierarchical energy management system for stand-alone hybrid system based on generation costs and cascade control

    International Nuclear Information System (INIS)

    Torreglosa, J.P.; García, P.; Fernández, L.M.; Jurado, F.

    2014-01-01

    Highlights: • We present an energy management system for a stand-alone WT/PV/hydrogen/battery hybrid system. • Hierarchical control composed by master and slave control strategies. • Control assures reliable electricity support for stand-alone applications subject to technical and economic criteria. - Abstract: This paper presents an energy management system (EMS) for stand-alone hybrid systems composed by photovoltaic (PV) solar panels and a wind turbine (WT) as primary energy sources and two energy storage systems, which are a hydrogen system and a battery. The hydrogen system is composed of fuel cell (FC), electrolyzer and hydrogen storage tank. The EMS is a hierarchical control composed by a master control strategy and a slave control strategy. On the one hand, the master control generates the reference powers to meet several premises (such as to satisfy the load power demand, and to maintain the hydrogen tank level and the state of charge (SOC) of the battery between their target margins), taking also into account economic aspects to discriminate between using the battery or hydrogen system. On the other hand, the slave control modifies the reference powers generated by the master control according to the energy sources dynamic limitations, and maintains the DC bus voltage at its reference value. The models, implemented in MATLAB-Simulink environment, have been developed from commercially available components. To check the viability of the proposed EMS, two kinds of simulations were carried out: (1) A long-term simulation of 25 years (expected lifetime of the system) with a sample time of one hour to validate the master control of the EMS; and (2) A short-term simulation with sudden net power variations to validate the slave control of the EMS

  13. Drive Stands

    Data.gov (United States)

    Federal Laboratory Consortium — The Electrical Systems Laboratory (ESL)houses numerous electrically driven drive stands. A drive stand consists of an electric motor driving a gearbox and a mounting...

  14. Veterans Health Administration: Management Attention Is Needed to Address Systemic, Long standing Human Capital Challenges

    Science.gov (United States)

    2016-12-01

    assess VHA’s employee performance management processes, we reviewed VA directives and handbooks , and procedures related to the performance...primary pay and classification system.30 VHA’s HR staff are classified as either an HR specialist, who manage , supervise, and deliver HR products ...Board. 815 C.F.R. § 430; Department of Veterans Affairs, Performance Management Systems, VA Handbook 5013, Part I. VHA Needs to Strengthen

  15. Post-fire diversity and abundance in pine and eucalipt stands in Portugal: effects of biogeography, topography, forest type and post-fire management

    OpenAIRE

    Maia, P.; Keizer, J.; Vasques, A.; Abrantes, N.; Roxo, L.; Fernandes, P.; Ferreira, A.; Moreira, F.

    2014-01-01

    This study concerned the mid-term regeneration of the woody understory vegetation of pure and mixed stands of Pinus pinaster Ait. and Eucalyptus globulus Labill. in northern and central Portugal following wildfires in 2005 and 2006. Pine and eucalypt stands are the most widespread and most fire-prone forest types in Portugal. The main aim was to investigate the importance of biogeography, topography, forest type and post-fire management operations in explaining the patterns in shr...

  16. Assessing Student Preconceptions of Sport Management Faculty: Where Do Women and Latinos Stand?

    Science.gov (United States)

    Sosa, Jason; Sagas, Michael

    2008-01-01

    Latino individuals and women as a group have found it difficult to become established within the professorate. As such, the purpose of this study was to examine student preconceptions of Latino professors within sport management. The study was conducted within a sport management class (N = 102), utilizing self-categorization theory based on race…

  17. Associations between disability-management self-efficacy, participation and life satisfaction in people with long-standing spinal cord injury

    NARCIS (Netherlands)

    Cijsouw, A; Adriaansen, Jacinthe J. E.; Tepper, M.; Dijksta, C A; van der Linden, S.; de Groot, S.; Post, M. W. M.; van der Woude, Lucas

    2017-01-01

    Objectives: To study disability-management self-efficacy (DMSE) and its correlates in a large sample of Dutch people with long-standing spinal cord injury (SCI). DMSE is the confidence that people with SCI may have in their ability to manage the consequences of their condition with respect to the

  18. Species Composition, Tree Quality and Wood Properties of Southern Pine Stands Under Ecosystemm Management on National Forests in the Peidmont and Coastal Plain

    Science.gov (United States)

    Alexander Clark; James W. McMinn

    1999-01-01

    National Forests in the United States are under sustainable ecosystem management to conserve biodiversity, achieve sustainable conditions and improve the balance among forest values. This paper reports on a study established to identify the implications of ecosystem management strategies on natural stands in the Piedmont and Coastal Plain. The impact of partial...

  19. Detection of dead standing Eucalyptus camaldulensis without tree delineation for managing biodiversity in native Australian forest

    Science.gov (United States)

    Miltiadou, Milto; Campbell, Neil D. F.; Gonzalez Aracil, Susana; Brown, Tony; Grant, Michael G.

    2018-05-01

    In Australia, many birds and arboreal animals use hollows for shelters, but studies predict shortage of hollows in near future. Aged dead trees are more likely to contain hollows and therefore automated detection of them plays a substantial role in preserving biodiversity and consequently maintaining a resilient ecosystem. For this purpose full-waveform LiDAR data were acquired from a native Eucalypt forest in Southern Australia. The structure of the forest significantly varies in terms of tree density, age and height. Additionally, Eucalyptus camaldulensis have multiple trunk splits making tree delineation very challenging. For that reason, this paper investigates automated detection of dead standing Eucalyptus camaldulensis without tree delineation. It also presents the new feature of the open source software DASOS, which extracts features for 3D object detection in voxelised FW LiDAR. A random forest classifier, a weighted-distance KNN algorithm and a seed growth algorithm are used to create a 2D probabilistic field and to then predict potential positions of dead trees. It is shown that tree health assessment is possible without tree delineation but since it is a new research directions there are many improvements to be made.

  20. Songbird response to alternative forest density management in young Douglas-fir stands

    Science.gov (United States)

    Joan C. Hagar

    2013-01-01

    Th inning has been increasingly used in the Pacifi c Northwest to restore structural and biological diversity to densely-stocked young- to mid-aged forests that have been previously intensively managed for timber production. In the short term, thinning promotes development of understory vegetation, which in turn can increase habitat diversity for wildlife, particularly...

  1. Intensive management modifies soil CO2 efflux in 6-year-old Pinus taeda L. stands

    Science.gov (United States)

    Lisa J. Samuelson; Kurt Johnsen; Tom Stokes; Weinlang Lu

    2004-01-01

    Intensive forestry may reduce net CO2 emission into atmosphere by storing carbon in living biomass, dead organic matter and soil, and durable wood products. Because quantification of belowground carbon dynamics is important for reliable estimation of the carbon sequestered by intensively managed plantations, we examined soil CO2...

  2. Developments to the Sylvan stand structure model to describe wood quality changes in southern bottomland hardwood forests because of forest management

    Science.gov (United States)

    Ian R. Scott

    2009-01-01

    Growth models can produce a wealth of detailed information that is often very difficult to perceive because it is frequently presented either as summary tables, stand view or landscape view visualizations. We have developed new tools for use with the Sylvan model (Larsen 1994) that allow the analysis of wood-quality changes as a consequence of forest management....

  3. Current Controversies in the Prediction, Diagnosis, and Management of Cerebral Vasospasm: Where Do We Stand?

    Directory of Open Access Journals (Sweden)

    Young Lee

    2013-01-01

    Full Text Available Aneurysmal subarachnoid hemorrhage occurs in approximately 30,000 persons in the United States each year. Around 30 percent of patients with aneurysmal subarachnoid hemorrhage suffer from cerebral ischemia and infarction due to cerebral vasospasm, a leading cause of treatable death and disability following aneurysmal subarachnoid hemorrhage. Methods used to predict, diagnose, and manage vasospasm are the topic of recent active research. This paper utilizes a comprehensive review of the recent literature to address controversies surrounding these topics. Evidence regarding the effect of age, smoking, and cocaine use on the incidence and outcome of vasospasm is reviewed. The abilities of different computed tomography grading schemes to predict vasospasm in the aftermath of subarachnoid hemorrhage are presented. Additionally, the utility of different diagnostic methods for the detection and visualization of vasospasm, including transcranial Doppler ultrasonography, CT angiography, digital subtraction angiography, and CT perfusion imaging is discussed. Finally, the recent literature regarding interventions for the prophylaxis and treatment of vasospasm, including hyperdynamic therapy, albumin, calcium channel agonists, statins, magnesium sulfate, and endothelin antagonists is summarized. Recent studies regarding each topic were reviewed for consensus recommendations from the literature, which were then presented.

  4. Current controversies in the prediction, diagnosis, and management of cerebral vasospasm: where do we stand?

    Science.gov (United States)

    Lee, Young; Zuckerman, Scott L; Mocco, J

    2013-01-01

    Aneurysmal subarachnoid hemorrhage occurs in approximately 30,000 persons in the United States each year. Around 30 percent of patients with aneurysmal subarachnoid hemorrhage suffer from cerebral ischemia and infarction due to cerebral vasospasm, a leading cause of treatable death and disability following aneurysmal subarachnoid hemorrhage. Methods used to predict, diagnose, and manage vasospasm are the topic of recent active research. This paper utilizes a comprehensive review of the recent literature to address controversies surrounding these topics. Evidence regarding the effect of age, smoking, and cocaine use on the incidence and outcome of vasospasm is reviewed. The abilities of different computed tomography grading schemes to predict vasospasm in the aftermath of subarachnoid hemorrhage are presented. Additionally, the utility of different diagnostic methods for the detection and visualization of vasospasm, including transcranial Doppler ultrasonography, CT angiography, digital subtraction angiography, and CT perfusion imaging is discussed. Finally, the recent literature regarding interventions for the prophylaxis and treatment of vasospasm, including hyperdynamic therapy, albumin, calcium channel agonists, statins, magnesium sulfate, and endothelin antagonists is summarized. Recent studies regarding each topic were reviewed for consensus recommendations from the literature, which were then presented.

  5. Phosphorous fractions in soils of rubber-based agroforestry systems: Influence of season, management and stand age.

    Science.gov (United States)

    Liu, Chenggang; Jin, Yanqiang; Liu, Changan; Tang, Jianwei; Wang, Qingwei; Xu, Mingxi

    2018-03-01

    Rubber-based agroforestry system is a vital management practice and its productivity is often controlled by soil phosphorus (P) nutrient, but little information is available on P fractions dynamics in such system. The aim of this study was to examine the seasonal, management and stand age effects on P fractions, acid phosphatase activity, microbial biomass P, other physical-chemical properties and litter and roots in four systems: 10-year-old rubber mono- (YM) and intercropping (YI) with N-fixing species (NFS), 22-year-old mono- (MM) and intercropping (MI) in Xishuangbanna, Southwestern China. Most P fractions varied seasonally at different depths, with highest values in the fog-cool season (i.e. labile P at 5-60cm, non-labile P and total P at 30-60cm). By contrast, moderately labile P varied little over time, except in MI that had lower values in the rainy season. Compared with their monoculture counterparts, YI doubled resin-P i concentration but decreased NaHCO 3 -extractable P, HCl-P i and residual-P o at the 0-30cm depth, whereas MI had hardly any changes in P species at the 60-cm depth. Surprisingly, residual-P o was enriched down to the deepest soil (30-60cm) in both YI and MI in the fog-cool season. All P fractions, except NaOH 0.1 -P i , were greatly reduced with increasing stand age. In addition to plants uptake, these changes can be explained by seasonality in soil environments (e.g. moisture, temperature, pH and microbial activity) and decomposition of litter and roots. Moreover, YI decreased labile P o stock, but MI increased moderately labile P i at the 60-cm depth across seasons. The results imply that a large amount of residual-P o exists in acidic Oxisol from China and that they can be reasonably exploited to reduce the application of P fertilizers, highlighting the importance of P o pool. Taken together, intercropping mature rubber plantation with NFS appears to be an effective way to enhance productivity while maintaining adequate soil P

  6. Development, succession, and stand dynamics of upland oak forests in the Wisconsin Driftless Area: Implications for oak regeneration and management

    Science.gov (United States)

    Megan L. Buchanan; Kurt F. Kipfmueller; Anthony W. D' Amato

    2017-01-01

    Throughout the deciduous forests of the eastern United States, oak (Quercus) regeneration has declined in stands historically dominated by oak species. In the Wisconsin Driftless Area, the level of decline in oak regeneration is variable and influenced by stand structural development, historical disturbance regime, abiotic site characteristics, and...

  7. Rotated sigmoid structures in managed uneven-aged northern hardwood stands: a look at the Burr Type III distribution

    Science.gov (United States)

    Jeffrey H. Gove; Mark J. Ducey; William B. Leak; Lianjun Zhang

    2008-01-01

    Stand structures from a combined density manipulation and even- to uneven-aged conversion experiment on the Bartlett Experimental Forest (New Hampshire, USA) were examined 25 years after initial treatment for rotated sigmoidal diameter distributions. A comparison was made on these stands between two probability density functions for fitting these residual structures:...

  8. Influence of thinning intensity and canopy type on Scots pine stand and growth dynamics in a mixed managed forest

    Energy Technology Data Exchange (ETDEWEB)

    Primicia, I.; Artázcoz, R.; Imbert, J.B.; Puertas, F.; Traver, M.C.; Castillo, F.J.

    2016-07-01

    Aim of the study: We analysed the effects of thinning intensity and canopy type on Scots pine growth and stand dynamics in a mixed Scots pine-beech forest. Area of the study: Western Pyrenees. Material and methods: Three thinning intensities were applied in 1999 (0, 20 and 30% basal area removed) and 2009 (0, 20 and 40%) on 9 plots. Within each plot, pure pine and mixed pine-beech patches are distinguished. All pine trees were inventoried in 1999, 2009 and 2014. The effects of treatments on the tree and stand structure variables (density, basal area, stand and tree volume), on the periodic annual increment in basal area and stand and tree volume, and on mortality rates, were analysed using linear mixed effects models. Main Results: The enhancement of tree growth was mainly noticeable after the second thinning. Growth rates following thinning were similar or higher in the moderate than in the severe thinning. Periodic stand volume annual increments were higher in the thinned than in the unthinned plots, but no differences were observed between the thinned treatments. We observed an increase in the differences of the Tree volume annual increment between canopy types (mixed < pure) over time in the unthinned plots, as beech crowns developed. Research highlights: Moderate thinning is suggested as an appropriate forest practice at early pine age in these mixed forests, since it produced higher tree growth rates than the severe thinning and it counteracted the negative effect of beech on pine growth observed in the unthinned plots. (Author)

  9. Soil carbon and nitrogen content and stabilization in mid-rotation, intensively managed sweetgum and loblolly stands

    Science.gov (United States)

    Kurt H. Johnsen; Lisa J. Samuelson; Felipe G. Sanchez; Bob Eaton

    2013-01-01

    Intensive forestry has resulted in considerable increases in aboveground stand productivity including foliar and belowground biomass which are the primary sources of soil organic matter. Soil organic matter is important for the maintenance of soil physical, chemical and biological quality. Additionally, sequestering carbon (C) in soils may provide a means of mitigating...

  10. Changes in species, grade, and structure over 48 years in a managed New England northern hardwood stand

    Science.gov (United States)

    William B. Leak; Paul E. Sendak

    2002-01-01

    Three individual-tree selection harvests over a 48 yr period in a northern hardwood stand in New Hampshire resulted in an increase in the percentage of volume in trees with grade 1 and 2 butt logs from 21% (1952) to 30% (2000) in beech and 40% (1952) to 65% (2000) in sugar maple and other hardwoods. By 2000, 90% of the volume was in tolerant species.

  11. Variability of sun-induced chlorophyll fluorescence according to stand age-related processes in a managed loblolly pine forest.

    Science.gov (United States)

    Colombo, Roberto; Celesti, Marco; Bianchi, Remo; Campbell, Petya K E; Cogliati, Sergio; Cook, Bruce D; Corp, Lawrence A; Damm, Alexander; Domec, Jean-Christophe; Guanter, Luis; Julitta, Tommaso; Middleton, Elizabeth M; Noormets, Asko; Panigada, Cinzia; Pinto, Francisco; Rascher, Uwe; Rossini, Micol; Schickling, Anke

    2018-02-20

    Leaf fluorescence can be used to track plant development and stress, and is considered the most direct measurement of photosynthetic activity available from remote sensing techniques. Red and far-red sun-induced chlorophyll fluorescence (SIF) maps were generated from high spatial resolution images collected with the HyPlant airborne spectrometer over even-aged loblolly pine plantations in North Carolina (United States). Canopy fluorescence yield (i.e., the fluorescence flux normalized by the light absorbed) in the red and far-red peaks was computed. This quantifies the fluorescence emission efficiencies that are more directly linked to canopy function compared to SIF radiances. Fluorescence fluxes and yields were investigated in relation to tree age to infer new insights on the potential of those measurements in better describing ecosystem processes. The results showed that red fluorescence yield varies with stand age. Young stands exhibited a nearly twofold higher red fluorescence yield than mature forest plantations, while the far-red fluorescence yield remained constant. We interpreted this finding in a context of photosynthetic stomatal limitation in aging loblolly pine stands. Current and future satellite missions provide global datasets of SIF at coarse spatial resolution, resulting in intrapixel mixture effects, which could be a confounding factor for fluorescence signal interpretation. To mitigate this effect, we propose a surrogate of the fluorescence yield, namely the Canopy Cover Fluorescence Index (CCFI) that accounts for the spatial variability in canopy structure by exploiting the vegetation fractional cover. It was found that spatial aggregation tended to mask the effective relationships, while the CCFI was still able to maintain this link. This study is a first attempt in interpreting the fluorescence variability in aging forest stands and it may open new perspectives in understanding long-term forest dynamics in response to future climatic

  12. Take a Stand!

    DEFF Research Database (Denmark)

    Danquah, I. H.; Kloster, S.; Holtermann, A.

    2017-01-01

    workers in total) were cluster randomized for intervention or control. The intervention included the appointment of local ambassadors, management support, environmental changes, a lecture and a workshop. Sitting time was measured using an ActiGraph GT3X+ fixed on the thigh. Data were processed using Acti4......Background: Prolonged sitting time has been associated with adverse health outcomes. Interventions at work may contribute to reduced sitting. The objective was to test if a multicomponent work-based intervention can reduce sitting time and the number of prolonged sitting periods (> 30 min......), increase the number of sit-to-stand transitions and decrease waist circumference and body fat percentage among office workers. Primary outcomes were: change in sitting time, prolonged sitting periods and sit-to-stand transitions at followup 1 month later. Methods: At four workplaces, 19 offices (317...

  13. Associations between disability-management self-efficacy, participation and life satisfaction in people with long-standing spinal cord injury.

    Science.gov (United States)

    Cijsouw, A; Adriaansen, J J E; Tepper, M; Dijksta, C A; van Linden, S; de Groot, S; Post, M W M

    2017-01-01

    To study disability-management self-efficacy (DMSE) and its correlates in a large sample of Dutch people with long-standing spinal cord injury (SCI). DMSE is the confidence that people with SCI may have in their ability to manage the consequences of their condition with respect to the various domains in their life. Research questions were: (1) What is the level of DMSE in Dutch people with long-standing SCI?; (2) Is DMSE associated with demographic and lesion characteristics?; and (3) Is DMSE associated with participation and life satisfaction if these associations are adjusted for demographic and lesion characteristics and mood? Eligible people were identified from all eight rehabilitation centers with a specialty in SCI rehabilitation in the Netherlands (N=261). Data were collected using a self-report questionnaire. DMSE was measured using the University of Washington Self-Efficacy Scale-Short Form (UW-SES-6). Correlation and linear regression analyses were used. Levels of UW-SES-6 scores were largely independent of demographic and lesion characteristics. UW-SES-6 scores were bivariately moderately to strongly associated with mood (0.47), participation (0.39-0.51) and life satisfaction (0.46). In the regression analyses, UW-SES-6 scores still explained a significant amount of variance of participation (standardized β 0.31-0.33) and life satisfaction (standardized β 0.21) when controlling for demographic and lesion characteristics and mood, and explained an additional 3.2-8.1% of the variance of participation and life satisfaction. DMSE is a psychological resource associated with higher levels of participation and life satisfaction after SCI. The UW-SES-6 is a brief and easy to use measure of this psychological resource.

  14. Soil respiration, microbial biomass and exoenzyme activity in switchgrass stands under nitrogen fertilization management and climate warming.

    Science.gov (United States)

    Jian, S.; Li, J.; de Koff, J.; Celada, S.; Mayes, M. A.; Wang, G.; Guo, C.

    2016-12-01

    Switchgrass (Panicum virgatum L.), as a model bioenergy crop, received nitrogen fertilizers for increasing its biomass yields. Studies rarely investigate the interactive effects of nitrogen fertilization and climate warming on soil microbial activity and carbon cycling in switchgrass cropping systems. Enhanced nitrogen availability under fertilization can alter rates of soil organic matter decomposition and soil carbon emissions to the atmosphere and thus have an effect on climate change. Here, we assess soil CO2 emission, microbial biomass and exoenzyme activities in two switchgrass stands with no fertilizer and 60 lbs N / acre. Soils were incubated at 15 ºC and 20 ºC for 180-day. Dry switchgrass plant materials were added to incubation jars and the 13C stable isotopic probing technique was used to monitor soil CO2 respiration derived from relatively labile litter and indigenous soil. Measurements of respiration, δ13C of respiration, microbial biomass carbon and exoenzyme activity were performed on days 1, 5, 10, 15, 30, 60, 90, 120, 150 and 180. Soil respiration rate was greater in the samples incubated at 20 ºC as compared to those incubated at 15 ºC. Exoenzyme activities were significantly altered by warming, litter addition and nitrogen fertilization. There was a significant interactive effect of nitrogen fertilization and warming on the proportion of CO2 respired from soils such that nitrogen fertilization enhanced warming-induced increase by 12.0% (Pmineralization. Fertilization increased soil microbial biomass carbon at both temperatures (9.0% at 15 ºC and 14.5% at 20 ºC). Our preliminary analysis suggested that warming effects on enhanced soil respiration can be further increased with elevated fertilizer input via greater microbial biomass and exoenzyme activity. In addition to greater biomass yield under N fertilization, this study informs potential soil carbon loss from stimulated soil respiration under nitrogen fertilization and warming in

  15. Fertilization effects on forest carbon storage and exchange, and net primary production: A new hybrid process model for stand management

    Science.gov (United States)

    D. A. Sampson; R. H. Waring; C. A. Maier; C. M. Gough; M. J. Ducey; K. H. Johnsen

    2006-01-01

    A critical ecological question in plantation management is whether fertilization, which generally increases yield, results in enhanced C sequestration over short rotations. We present a rotation-length hybrid process model (SECRETS-3PG) that was calibrated (using control treatments; CW) and verified (using fertilized treatments; FW) using daily estimates of H

  16. Fuel cells, batteries and super-capacitors stand-alone power systems management using optimal/flatness based-control

    Energy Technology Data Exchange (ETDEWEB)

    Benaouadj, M.; Aboubou, A.; Bahri, M.; Boucetta, A. [MSE Laboratory, Mohamed khiderBiskra University (Algeria); Ayad, M. Y., E-mail: ayadmy@gmail.com [R& D, Industrial Hybrid Vehicle Applications (France)

    2016-07-25

    In this work, an optimal control (under constraints) based on the Pontryagin’s maximum principle is used to optimally manage energy flows in a basic PEM (Proton Exchange Membrane) fuel cells system associated to lithium-ion batteries and supercapacitors through a common DC bus having a voltage to stabilize using the differential flatness approach. The adaptation of voltage levels between different sources and load is ensured by use of three DC-DC converters, one boost connected to the PEM fuel cells, while the two others are buck/boost and connected to the lithiumion batteries and supercapacitors. The aim of this paper is to develop an energy management strategy that is able to satisfy the following objectives: Impose the power requested by a habitat (representing the load) according to a proposed daily consumption profile, Keep fuel cells working at optimal power delivery conditions, Maintain constant voltage across the common DC bus, Stabilize the batteries voltage and stored quantity of charge at desired values given by the optimal control. Results obtained under MATLAB/Simulink environment prove that the cited objectives are satisfied, validating then, effectiveness and complementarity between the optimal and flatness concepts proposed for energy management. Note that this study is currently in experimentally validation within MSE Laboratory.

  17. Standing footprint diagnostic method

    Science.gov (United States)

    Fan, Y. F.; Fan, Y. B.; Li, Z. Y.; Newman, T.; Lv, C. S.; Fan, Y. Z.

    2013-10-01

    Center of pressure is commonly used to evaluate standing balance. Even though it is incomplete, no better evaluation method has been presented. We designed our experiment with three standing postures: standing with feet together, standing with feet shoulder width apart, and standing with feet slightly wider than shoulder width. Our platform-based pressure system collected the instantaneous plantar pressure (standing footprint). A physical quantity of instantaneous standing footprint principal axis was defined, and it was used to construct an index to evaluate standing balance. Comparison between results from our newly established index and those from the center of pressure index to evaluate the stability of different standing postures revealed that the standing footprint principal axis index could better respond to the standing posture change than the existing one. Analysis indicated that the insensitive response to the relative position between feet and to the standing posture change from the center of pressure could be better detected by the standing footprint principal axis index. This predicts a wide application of standing footprint principal axis index when evaluating standing balance.

  18. Thermal management of thermoacoustic sound projectors using a free-standing carbon nanotube aerogel sheet as a heat source.

    Science.gov (United States)

    Aliev, Ali E; Mayo, Nathanael K; Baughman, Ray H; Avirovik, Dragan; Priya, Shashank; Zarnetske, Michael R; Blottman, John B

    2014-10-10

    Carbon nanotube (CNT) aerogel sheets produce smooth-spectra sound over a wide frequency range (1-10(5) Hz) by means of thermoacoustic (TA) sound generation. Protective encapsulation of CNT sheets in inert gases between rigid vibrating plates provides resonant features for the TA sound projector and attractive performance at needed low frequencies. Energy conversion efficiencies in air of 2% and 10% underwater, which can be enhanced by further increasing the modulation temperature. Using a developed method for accurate temperature measurements for the thin aerogel CNT sheets, heat dissipation processes, failure mechanisms, and associated power densities are investigated for encapsulated multilayered CNT TA heaters and related to the thermal diffusivity distance when sheet layers are separated. Resulting thermal management methods for high applied power are discussed and deployed to construct efficient and tunable underwater sound projector for operation at relatively low frequencies, 10 Hz-10 kHz. The optimal design of these TA projectors for high-power SONAR arrays is discussed.

  19. Thermal management of thermoacoustic sound projectors using a free-standing carbon nanotube aerogel sheet as a heat source

    International Nuclear Information System (INIS)

    Aliev, Ali E; Mayo, Nathanael K; Baughman, Ray H; Avirovik, Dragan; Priya, Shashank; Zarnetske, Michael R; Blottman, John B

    2014-01-01

    Carbon nanotube (CNT) aerogel sheets produce smooth-spectra sound over a wide frequency range (1–10 5 Hz) by means of thermoacoustic (TA) sound generation. Protective encapsulation of CNT sheets in inert gases between rigid vibrating plates provides resonant features for the TA sound projector and attractive performance at needed low frequencies. Energy conversion efficiencies in air of 2% and 10% underwater, which can be enhanced by further increasing the modulation temperature. Using a developed method for accurate temperature measurements for the thin aerogel CNT sheets, heat dissipation processes, failure mechanisms, and associated power densities are investigated for encapsulated multilayered CNT TA heaters and related to the thermal diffusivity distance when sheet layers are separated. Resulting thermal management methods for high applied power are discussed and deployed to construct efficient and tunable underwater sound projector for operation at relatively low frequencies, 10 Hz–10 kHz. The optimal design of these TA projectors for high-power SONAR arrays is discussed. (paper)

  20. Dose management in radiology. Review of the technological status; Dosismanagement in der Radiologie. Ein Ueberblick zum Stand der Technik

    Energy Technology Data Exchange (ETDEWEB)

    Verius, M. [LKH Innsbruck, Universitaetsklinik fuer Radiologie, Innsbruck (Austria)

    2015-08-15

    The Euratom directive 2013/59 (''EU directive for radiation protection'') has to be implemented into national law by spring 2018 and requires a complete recording of patient dosages and relevant parameters. Additionally, a medical physics expert has to be consulted for each radiological examination above a defined threshold. A complete recording of the dosage administered from all modalities and optimization of the radiological procedures should result in a reduction of the total dosage. This can be achieved by automated systems that incorporate not only the detection of the dose parameters but also the evaluation and analysis of these data. When provided with warning levels such a system should be able to inform or warn the operator when dose thresholds have been exceeded or even better inform the operator about possible excess dosages before an examination. Depending on the information provided by the modality, dose management systems can operate at different levels in the picture archiving and communication system (PACS), radiological and hospital information systems (RIS/HIS) or with the header information of a digital imaging and communications in medicine (DICOM) image and evaluate and analyze this data. A practicable use of such systems is only possible by close cooperation of medical personnel, medical physicists and information technology (IT) administrators. Various systems are available commercially or free but an individual adaptation of these systems is useful and necessary, depending on the requirements of the radiology practice or hospital. (orig.) [German] Die Euratom-Richtlinie 2013/59 (''EU-Richtlinie zum Strahlenschutz'') besagt, dass sie bis zum Fruehjahr 2018 in nationales Recht der Mitgliedstaaten umgesetzt werden muss, d. h. eine lueckenlose Erfassung der Patientendosen zu erfolgen hat. Ausserdem muss zu jeder Modalitaet in einem bestimmten Ausmass ein Medizinphysikexperte hinzugezogen werden. Die

  1. Post-fire plant diversity and abundance in pine and eucalypt stands in Portugal : Effects of biogeography, topography, forest type and post-fire management

    NARCIS (Netherlands)

    Maia, P.; Keizer, J.; Vasques, A.; Abrantes, N.; Roxo, L.; Fernandes, P.; Ferreira, A.; Moreira, F.

    2014-01-01

    This study concerned the mid-term regeneration of the woody understory vegetation of pure and mixed stands of Pinus pinaster Ait. and Eucalyptus globulus Labill. in northern and central Portugal following wildfires in 2005 and 2006. Pine and eucalypt stands are the most widespread and most

  2. Standing Concertation Committee

    CERN Multimedia

    HR Department

    2009-01-01

    Ordinary Meeting on 11 May 2009 The meeting of the Standing Concertation Committee held on 11 May 2009 was entirely dedicated to the preparation of the TREF meeting on 19 & 20 May 2009. The Committee took note, discussed and agreed on some clarifications on a number of documents and presentations that the Management planned to submit and/or present to TREF on the following subjects: • Personnel statistics 2008: J. Purvis presented the Personnel Statistics for 2008 prepared by HR Department. In line with the previous year, key messages were firstly, a general reduction in staff (2544 to 2400, - 6%), secondly, a reduction in administrative services personnel (from 422 to 387, - 8%) and thirdly, a marked increase in the number of Users and Unpaid Associates (from 8369 to 9140, + 9%) • Five-Yearly Review 2010: A series of draft documents were submitted for discussion, comprising an introductory document explaining the statutory basis for the following four document...

  3. Standing Concertation Committee

    CERN Document Server

    HR Department

    2010-01-01

    Main issues examined at the meeting of 2 October 2009 The October 2009 meeting of the Standing Concertation Committee was entirely devoted to preparation of TREF’s meeting on 21-22 October. The Committee took note of, discussed and agreed on clarifications needed to some of the documents and presentations that the Management intended to submit and/or present to TREF on the following subjects: Equal opportunities The Committee took note of a preliminary report on equal opportunities at CERN drawn up by D. Chromek-Burckhart, the Equal Opportunities Officer, and T. Smith, Chairman of the Equal Opportunities Advisory Panel, containing in particular a proposal for a new process for resolving harassment conflicts. Technical analysis of the CERN Health Insurance Scheme - Actuary’s Report The Committee took note of a presentation by P. Charpentier, Chairman of the CERN Health Insurance Supervisory Board (CHIS Board), on the 2009 actuarial report on the CERN Health Insurance Scheme (CHIS). Th...

  4. Standing Concertation Commmittee

    CERN Document Server

    HR Department

    2007-01-01

    Ordinary meeting on 2 november 2007 Extraordinary meeting on 12 November 2007 The main items discussed at the meetings of the Standing Concertation Committee on 2 November 2007 and 12 November included: Restaurants Supervisory Committee Report The committee took note of the report by the chairman of the Restaurants Supervisory Committee (RSC), T. Lagrange. In particular, it was recorded that, in Restaurant No. 1, the new kitchen and free flow arrangements had been inaugurated and all works had been commissioned on schedule in October 2007.The contractor, Novae, had taken over maintenance of the new kitchen. Some price increases were to be expected in the coming months due mainly to strong increases in the cost of basic ingredients. A problem with bad smells in the area of Restaurant No. 1 was being taken care of by tuning the ventilation system. The RSC wished to thank the management and staff of Restaurant No. 2 for their cooperation while Restaurant No 1 was ...

  5. CANGS DB: a stand-alone web-based database tool for processing, managing and analyzing 454 data in biodiversity studies

    Directory of Open Access Journals (Sweden)

    Schlötterer Christian

    2011-06-01

    Full Text Available Abstract Background Next generation sequencing (NGS is widely used in metagenomic and transcriptomic analyses in biodiversity. The ease of data generation provided by NGS platforms has allowed researchers to perform these analyses on their particular study systems. In particular the 454 platform has become the preferred choice for PCR amplicon based biodiversity surveys because it generates the longest sequence reads. Nevertheless, the handling and organization of massive amounts of sequencing data poses a major problem for the research community, particularly when multiple researchers are involved in data acquisition and analysis. An integrated and user-friendly tool, which performs quality control, read trimming, PCR primer removal, and data organization is desperately needed, therefore, to make data interpretation fast and manageable. Findings We developed CANGS DB (Cleaning and Analyzing Next Generation Sequences DataBase a flexible, stand alone and user-friendly integrated database tool. CANGS DB is specifically designed to organize and manage the massive amount of sequencing data arising from various NGS projects. CANGS DB also provides an intuitive user interface for sequence trimming and quality control, taxonomy analysis and rarefaction analysis. Our database tool can be easily adapted to handle multiple sequencing projects in parallel with different sample information, amplicon sizes, primer sequences, and quality thresholds, which makes this software especially useful for non-bioinformaticians. Furthermore, CANGS DB is especially suited for projects where multiple users need to access the data. CANGS DB is available at http://code.google.com/p/cangsdb/. Conclusion CANGS DB provides a simple and user-friendly solution to process, store and analyze 454 sequencing data. Being a local database that is accessible through a user-friendly interface, CANGS DB provides the perfect tool for collaborative amplicon based biodiversity surveys

  6. Thinning in artificially regenerated young beech stands

    Directory of Open Access Journals (Sweden)

    Novák Jiří

    2015-12-01

    Full Text Available Although beech stands are usually regenerated naturally, an area of up to 5,000 ha year−1 is artificially regenerated by beech in the Czech Republic annually. Unfortunately, these stands often showed insufficient stand density and, consequently, lower quality of stems. Therefore, thinning methods developed for naturally regenerated beech stands are applicable with difficulties. The paper evaluates the data from two thinning experiments established in young artificially regenerated beech stands located in different growing conditions. In both experiments, thinning resulted in the lower amount of salvage cut in following years. Positive effect of thinning on periodic stand basal area increment and on periodic diameter increment of dominant trees was found in the beech stand located at middle elevations. On the other hand, thinning effects in mountain conditions were negligible. Thinning focusing on future stand quality cannot be commonly applied in artificially regenerated beech stands because of their worse initial quality and lower density. However, these stands show good growth and response to thinning, hence their management can be focused on maximising beech wood production.

  7. Food Irradiation. Standing legislation

    International Nuclear Information System (INIS)

    Verdejo S, M.

    1997-01-01

    The standing legislation in Mexico on food irradiation matter has its basis on the Constitutional Policy of the Mexican United States on the 4 Th. article by its refers to Secretary of Health, 27 Th. article to the Secretary of Energy and 123 Th. of the Secretary of Work and Social Security. The laws and regulations emanated of the proper Constitution establishing the general features which gives the normative frame to this activity. The general regulations of Radiological Safety expedited by the National Commission for Nuclear Safety and Safeguards to state the specifications which must be fulfill the industrial installations which utilizing ionizing radiations, between this line is founded, just as the requirements for the responsible of the radiological protection and the operation of these establishments. The project of Regulation of the General Health Law in matter of Sanitary Control of Benefits and Services, that in short time will be officialized, include a specific chapter on food irradiation which considers the International Organizations Recommendations and the pertaining harmonization stated for Latin America, which elaboration was in charge of specialized group where Mexico was participant. Additionally, the Secretary of Health has a Mexican Official Standard NOM-033-SSA1-1993 named 'Food irradiation; permissible doses in foods, raw materials and support additives' standing from the year 1995, where is established the associated requirements to the control registers, service constancies and dose limits for different groups of foods, moreover of the specific guidelines for its process. This standard will be adequate considering the updating Regulation of Benefits and Services and the limits established the Regulation for Latin America. The associated laws that cover in general terms it would be the requirements for food irradiation although such term is not manageable. (Author)

  8. Planter unit test stand

    Science.gov (United States)

    A planter test stand was developed to evaluate individual row-crop metering units in early 2013. This test stand provided the ability to quantify actual seed metering in terms of population, seed spacing, skips, and multiples over a range of meter RPMs and vacuum pressures. Preliminary data has been...

  9. Standing Concertation Commmittee

    CERN Multimedia

    HR Department

    2007-01-01

    Ordinary meeting on 27 February 2007 The main items discussed at the meeting of the Standing Concertation Committee on 27 February 2007 included: Saved Leave Scheme (SLS): It was announced that a Management/Staff Association working group had been set up to discuss the Saved Leave Scheme (SLS): Members: M. Büttner, E. Chiaveri (chair), Ph. Defert, D. Klem, M. Vitasse, J.-M. Saint-Viteux. It was noted that the Staff Association was launching a questionnaire on SLS and distributed to all members of the personnel. Merit Recognition Guidelines : in the context of the new Merit Appraisal and Recognition Scheme (MARS), the committee took note of the CERN-wide 2007 Merit Recognition Guidelines, including the Frequently Asked Questions on HR Department's dedicated website. Information on CERN's medium and long-term plans (MTP-LTP)/Contract renewals/ External mobility The Committee took note of the information provided on CERN's MTP-LTP and of documentation distributed at the meeting by the Staff Associatio...

  10. Standing Concertation Committee

    CERN Document Server

    HR Department

    2007-01-01

    ORDINARY MEETING ON 27 FEBRUARY 2007 The main items discussed at the meeting of the Standing Concertation Committee on 27 February 2007 included: Saved Leave Scheme (SLS): It was announced that a Management/Staff Association working group had been set up to discuss the Saved Leave Scheme (SLS): Members : M. Büttner, E. Chiaveri (chair), Ph. Defert, D. Klem, M. Vitasse, J.-M. Saint-Viteux. It was noted that the Staff Association was launching a questionnaire on SLS and distributed to all members of the personnel. Merit Recognition Guidelines: In the context of the new Merit Appraisal and Recognition Scheme (MARS), the committee took note of the CERN-wide 2007 Merit Recognition Guidelines, including the Frequently Asked Questions on HR Department's dedicated website. Information on CERN's medium and long-term plans (MTP-LTP)/Contract renewals/ External mobility The Committee took note of the information provided on CERN's MTP-LTP and of documentation distributed at the meeting by the Staff ...

  11. Stand-up physics

    CERN Multimedia

    2009-01-01

    A CMS physicist and amateur stand up comic was named the winner of NESTA FameLab 2009. Tom Whyntie battled it out with nine others young scientists from across the UK to win the contest to find the country’s next top science communicator. Tom Whyntie with his prize money after the NESTA Famelab final.Tom Whyntie, who is currently doing his PhD on the CMS experiment, managed to persuade his supervisor to give him a few days off on 5 June so he could fly back to the UK for the final of NESTA FameLab 2009. In the competition, which has been dubbed ‘the X Factor for scientists’, he had just three minutes to explain a complex scientific idea to a panel of judges made up of high-profile science professionals. During the final, he captivated the audience with his talk about how finding nothing at the LHC, far from being a waste of £5 billion, would actually catalyse the next scientific revolution. It Whyntie’s own words: "If the L...

  12. Temperate and boreal old-growth forests: how do their growth dynamics and biodiversity differ from young stands and managed forests?

    NARCIS (Netherlands)

    Schulze, E.D.; Hessenmoeller, D; Knohl, A.; Luyssaert, S; Boerner, A; Grace, J.

    2009-01-01

    This chapter investigates biomass, net primary productivity (NPP), and net ecosystem productivity (NEP) of boreal and temperate forest ecosystems in relation to stand density and age. Forests may accumulate woody biomass at constant rate for centuries and there is little evidence of an age-related

  13. Stand Dynamics and Plant Associates of Loblolly Pine Plantations to Midrotation after Early Intensive Vegetation Management-A Southeastern United States Regional Study

    Science.gov (United States)

    James H. Miller; Bruce R. Zutter; Ray A. Newbold; M. Boyd Edwards; Shepard M. Zedaker

    2003-01-01

    Increasingly, pine plantations worldwide are grown using early control of woodv and/or herbaceous vegetation. Assuredsustainablepractices require long-term data on pine plantation development detailing patterns and processes to understand both crop-competition dynamics and the role of stand participants in providing multiple attributes such as biodiversity conservation...

  14. EULAR recommendations for the management of knee osteoarthritis: report of a task force of the Standing Committee for International Clinical Studies Including Therapeutic Trials (ESCISIT)

    NARCIS (Netherlands)

    Pendleton, A.; Arden, N.; Dougados, M.; Doherty, M.; Bannwarth, B.; Bijlsma, J. W.; Cluzeau, F.; Cooper, C.; Dieppe, P. A.; Günther, K. P.; Hauselmann, H. J.; Herrero-Beaumont, G.; Kaklamanis, P. M.; Leeb, B.; Lequesne, M.; Lohmander, S.; Mazieres, B.; Mola, E. M.; Pavelka, K.; Serni, U.; Swoboda, B.; Verbruggen, A. A.; Weseloh, G.; Zimmermann-Gorska, I.

    2000-01-01

    Osteoarthritis (OA) is the most common joint disease encountered throughout Europe. A task force for the EULAR Standing Committee for Clinical Trials met in 1998 to determine the methodological and logistical approach required for the development of evidence based guidelines for treatment of knee

  15. EULAR recommendations for the management of knee osteoarthritis. Report of a task force of the Standing Committee for International Clinical Studies Including Therapeutic Trials (ESCISIT)

    NARCIS (Netherlands)

    Pendleton, A.; Arden, N.; Dougados, M.; Doherty, M.; Bannwarth, B.; Bijlsma, J.; Cluzeau, F.; Cooper, C.; Dieppe, P.; Gunther, K. P.; Hauselmann, H.; Herrero-Beaumont, G.; Kaklamanis, P.; Leeb, B.; Littlejohn, M. L. P.; Lohmander, S.; Mazieres, B.; Mola, E. M.; Pavelka, K.; Serni, U.; Swoboda, B.; Verbruggen, G.; Weseloh, G.; Zimmermann-Gorska, I.

    2002-01-01

    Background Osteoarthritis (OA) is the most common joint disease encountered throughout Europe. A task force for the EULAR standing committee for clinical trials met in 1998 to determine the methodological and logistical approach required for the development of evidence-based guidelines for treatment

  16. Variable Attitude Test Stand

    Data.gov (United States)

    Federal Laboratory Consortium — The Variable Attitude Test Stand designed and built for testing of the V-22 tilt rotor aircraft propulsion system, is used to evaluate the effect of aircraft flight...

  17. Where We Now Stand

    Science.gov (United States)

    Lumsden, Keith G.

    1969-01-01

    Noting the acceleration of scientific evaluation, the author focuses his attention on where we now stand in the evaluation of two methods of instruction: programed learning materials and television. (Editor)

  18. The Stimulus test stand

    International Nuclear Information System (INIS)

    Christofek, L.; Rapidis, P.; Reinhard, A.; Fermilab

    2005-01-01

    The Stimulus Test Stand was originally constructed and assembled for testing the SVX2 ASIC readout and then upgraded for SVX3 ASIC prototyping and testing. We have modified this system for SVX4 ASIC [1] prototype testing. We described the individual components below. Additional details for other hardware for SVX4 testing can be found in reference [2]. We provide a description of the Stimulus Test Stand used for prototype testing of the SVX4 chip

  19. Stand and within-stand factors influencing Golden-winged Warbler use of regenerating stands in the central Appalachian Mountains

    Directory of Open Access Journals (Sweden)

    Marja H. Bakermans

    2015-06-01

    Full Text Available The Golden-winged Warbler (Vermivora chrysoptera is currently being considered for protected status under the U.S. Endangered Species Act. The creation of breeding habitat in the Appalachian Mountains is considered a conservation priority for this songbird, which is dependent on extensively forested landscapes with adequate availability of young forest. We modeled abundance of Golden-winged Warbler males in regenerating harvested forest stands that were 0-17 years postharvest at both mid-Appalachian and northeast Pennsylvania regional scales using stand and within-stand characteristics of 222 regenerating stands, 2010-2011. Variables that were most influential at the mid-Appalachian scale were different than those in the northeast region. Across the mid-Appalachian ecoregion, the proportion of young forest cover, i.e., shrub/scrub cover, within 1 km of regenerating stands best explained abundance of Golden-winged Warblers. Golden-winged Warbler response was best explained by a concave quadratic relationship in which abundance was highest with 5-15% land in young forest cover. We also found evidence that the amount of herbaceous cover, i.e., the amount of grasses and forbs, within a regenerating stand positively influenced abundance of Golden-winged Warblers. In northeastern Pennsylvania, where young forest cover is found in high proportions, the distance to the nearest regenerating stand best explained variation in abundance of Golden-winged Warblers. Abundance of Golden-winged Warblers was 1500 m away. When modeling within-stand features in the northeast region, many of the models were closely ranked, indicating that multiple variables likely explained Golden-winged Warbler response to within-stand conditions. Based on our findings, we have proposed several management guidelines for land managers interested in creating breeding habitat for Golden-winged Warblers using commercial timber operations. For example, we recommend when managing for

  20. Ranking Thinning Potential of Lodgepole Pine Stands

    OpenAIRE

    United States Department of Agriculture, Forest Service

    1987-01-01

    This paper presents models for predicting edge-response of dominant and codominant trees to clearing. Procedures are given for converting predictions to a thinning response index, for ranking stands for thinning priority. Data requirements, sampling suggestions, examples of application, and suggestions for management use are included to facilitate use as a field guide.

  1. Construction alternatives for free-standing facilities.

    Science.gov (United States)

    Brown, G

    1990-01-01

    Many hospitals are exploring free-standing facilities as an option for providing more efficient imaging services. Mr. Brown discusses the pros and cons of an emerging building technology, manufactured construction, in which building and site preparation are done simultaneously. He presents the criteria managers should use to make a knowledgeable decision.

  2. Stand-alone XLIF

    DEFF Research Database (Denmark)

    Hansen, E. J.; Simony, A.; Hummel, Stefan

    2015-01-01

    and clinical/radiological results in 22 patients treated with XLIF procedure for DS or degenerative disc disease (DDD). Material and methods: 22 consecutive patients with DS underwent surgery with the XLIF stand-alone procedure, with follow-up of 24 months. Clinical outcome scores were collected. Complications......Introduction: Adult thoracolumbar degeneration is an increasing challenge in the aging population. With age the progressive degeneration of the discs leads to an asymmetric collapse and a thoracolumbar coronal plane deformity, a degenerative scoliosis (DS). Aim: To evaluate the complication rate......-year follow-up, with a 31.8% revision rate. Due to the high revision rate we recommend supplementary posterior instrumentation, to achieve a higher fusion rate. When considering XLIF-stand-alone procedure for DS or DDD without supplemental posterior instrumentation, only single-level disease should...

  3. Standing wave accelerating structures

    International Nuclear Information System (INIS)

    Zavadtsev, A.A.; Zverev, B.V.; Sobepin, N.P.

    1984-01-01

    Accelerating ELA structures are considered and chosen for applied purposes of special designation. Accelerating structures with the standing wave are considered most effective for small size ELA. Designs and results of experimental investigation of two new accelerating structures are described. These are structures of the ''ring'' type with a decreased number of excitinq oscillation types and strucuture with transverse rods with a twice smaller transverse size as compared with the biperiodical structure with internal connection resonators. The accelerating biperiodical structures of the conventional type by the fact that the whole structure is not a linear chain of connected resonators, but a ring one. Model tests have shown that the homogeneous structure with transverse rods (STR) at the frequency of 2.8 GHz in the regime of the standing wave has an effective shunt resistance equalling 23 MOhm/m. It is shown that the small transverse size of biperiodic STR makes its application in logging linear electron accelerators

  4. The health of loblolly pine stands at Fort Benning, GA

    Science.gov (United States)

    Soung-Ryoul Ryu; G. Geoff Wang; Joan L. Walker

    2013-01-01

    Approximately two-thirds of the red-cockaded woodpecker (Picoides borealis) (RCW) groups at Fort Benning, GA, depend on loblolly pine (Pinus taeda) stands for nesting or foraging. However, loblolly pine stands are suspected to decline. Forest managers want to replace loblolly pine with longleaf pine (P. palustris...

  5. Multi-Purpose Test Stand

    Data.gov (United States)

    Federal Laboratory Consortium — The Multi-Purpose Test Stand is used for a wide variety of tests. The Stand is designed to be rotated through a range of fixed yaw positions to allow engines to be...

  6. Effects of stand and inter-specific stocking on maximizing standing tree carbon stocks in the eastern United States

    Science.gov (United States)

    Christopher W. Woodall; Anthony W. D' Amato; John B. Bradford; Andrew O. Finley

    2011-01-01

    There is expanding interest in management strategies that maximize forest carbon (C) storage to mitigate increased atmospheric carbon dioxide. The tremendous tree species diversity and range of stand stocking found across the eastern United States presents a challenge for determining optimal combinations for the maximization of standing tree C storage. Using a...

  7. EULAR recommendations for the management of early arthritis: report of a task force of the European Standing Committee for International Clinical Studies Including Therapeutics (ESCISIT)

    NARCIS (Netherlands)

    Combe, B.; Landewe, R.; Lukas, C.; Bolosiu, H. D.; Breedveld, F.; Dougados, M.; Emery, P.; Ferraccioli, G.; Hazes, J. M. W.; Klareskog, L.; Machold, K.; Martin-Mola, E.; Nielsen, H.; Silman, A.; Smolen, J.; Yazici, H.

    2007-01-01

    To formulate EULAR recommendations for the management of early arthritis. In accordance with EULAR's "standardised operating procedures", the task force pursued an evidence based approach and an approach based on expert opinion. A steering group comprised of 14 rheumatologists representing 10

  8. Effects of dwarf pine stands on slope deformation processes, as a basis for their management in the Hrubý Jeseník Mts

    Czech Academy of Sciences Publication Activity Database

    Roštínský, Pavel; Šenfeldr, M.; Maděra, P.

    2013-01-01

    Roč. 6, č. 1 (2013), s. 63-83 ISSN 1803-2427 Grant - others:GA MŠk(CZ) EE2.3.20.0004 Institutional support: RVO:68145535 Keywords : hazardous slope deformation * non-indigenous dwarf pine * management approach Subject RIV: DE - Earth Magnetism, Geodesy, Geography http://www.journaloflandscapeecology.cz/index.php?page=issues

  9. Regeneratoin Development 3 Years After Thinning and Fertilization in an East Texas Bottomland Hardwood Stand (To Manage or To Regenerate: Can We Do Both?)

    Science.gov (United States)

    Brian Roy Lockhart; Alexander J. Michalek; Matthew W. Lowe; Richard A. Williams

    2004-01-01

    Silviculture textbooks state that intermediate treatments, such as thinning, are prescribed to regulate the growing space for the benefit of existing trees and not to create enough growing space to initiate new trees of desirable species. If new, desirable regeneration develops, then it is considered a by-product of the intermediate treatment and is not to be managed,...

  10. Empresas que se destacam pela qualidade das informações a seus usuários externos também se destacam pela utilização de artefatos modernos de contabilidade gerencial? Do companies who stand out for information quality for external users also stand out for the use of modern management accounting artifacts?

    Directory of Open Access Journals (Sweden)

    Reinaldo Guerreiro

    2011-04-01

    Full Text Available Estudos empíricos têm indicado baixo grau de utilização de artefatos modernos de Contabilidade Gerencial propostos pela literatura. No âmbito teórico, a teoria da contabilidade engloba o pressuposto de que a contabilidade deveria atender eficazmente os seus usuários externos e internos. Este estudo tem dois objetivos principais: avaliar se (a empresas brasileiras que se destacam pelo seu porte na economia brasileira utilizam artefatos modernos de Contabilidade Gerencial e (b empresas que se destacam pela qualidade de suas informações aos usuários externos, também, se destacam pela maior utilização de artefatos modernos de Contabilidade Gerencial de apoio a usuários internos. Uma amostra de 90 empresas foi examinada, selecionadas dentre empresas listadas entre as 500 maiores empresas (edição de 2005 de Melhores e Maiores e dentre o rol de empresas que foram indicadas ao Prêmio ANEFAC-FIPECAFI-SERASA, Troféu Transparência, entre os anos-base de 1996 a2004. Dados foram coletados por meio de questionário endereçado ao gestor da área de Contabilidade Gerencial, contendo questões relativas ao grau de utilização de artefatos tradicionais e modernos de Contabilidade Gerencial. Os resultados do estudo demonstram que (a as empresas da amostra utilizam artefatos modernos de Contabilidade Gerencial e (b a amostra de empresas indicadas para o prêmio não se diferencia, em termos de utilização de artefatos modernos de Contabilidade Gerencial, do grupo das demais empresas pesquisadas.Empirical studies have indicated low levels of adoption of modern management accounting artifacts, as suggested by the literature. Accounting theory encompasses the assumption that accounting should effectively assist both internal and external users. The present study aims at two main goals: to evaluate whether (a large Brazilian companies actually use modern management accounting artifacts; and (b companies that stand out by the quality of information

  11. Variable strength of forest stand attributes and weather conditions on the questing activity of Ixodes ricinus ticks over years in managed forests.

    Directory of Open Access Journals (Sweden)

    Ralf Lauterbach

    Full Text Available Given the ever-increasing human impact through land use and climate change on the environment, we crucially need to achieve a better understanding of those factors that influence the questing activity of ixodid ticks, a major disease-transmitting vector in temperate forests. We investigated variation in the relative questing nymph densities of Ixodes ricinus in differently managed forest types for three years (2008-2010 in SW Germany by drag sampling. We used a hierarchical Bayesian modeling approach to examine the relative effects of habitat and weather and to consider possible nested structures of habitat and climate forces. The questing activity of nymphs was considerably larger in young forest successional stages of thicket compared with pole wood and timber stages. Questing nymph density increased markedly with milder winter temperatures. Generally, the relative strength of the various environmental forces on questing nymph density differed across years. In particular, winter temperature had a negative effect on tick activity across sites in 2008 in contrast to the overall effect of temperature across years. Our results suggest that forest management practices have important impacts on questing nymph density. Variable weather conditions, however, might override the effects of forest management practices on the fluctuations and dynamics of tick populations and activity over years, in particular, the preceding winter temperatures. Therefore, robust predictions and the detection of possible interactions and nested structures of habitat and climate forces can only be quantified through the collection of long-term data. Such data are particularly important with regard to future scenarios of forest management and climate warming.

  12. Substance management in thermal waste treatment plants. Final report; Stoffmanagement in thermischen Abfallbehandlungsanlagen. Stand und Perspektiven der thermischen Abfallbehandlung in Europa. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Leclaire, T; Meyer, B; Neumann, P; Schiemann, J; Schmidt, K G [Institut fuer Umwelttechnologie und Umweltanalytik e.V. (IUTA), Duisburg (Germany); Mast, P G [TAUW Umwelt GmbH, Mannheim (Germany)

    1996-08-01

    The report gives a general view of the actual state of development of the thermal waste treatment and the further need of research. It mentions the importance of the standarization of legal framework in the european waste management and the problems, that result from the internationalization of waste management and the conversion of European guidelines into national law. In 19 lectures with following discussions, which results are written down summed up together with the lectures, - the situation of the (thermal) waste treatment in different european states - the technologies of - municipal waste incineration - alternative thermal treatment methods - mechanical-biological waste treatment (in integrated treatment conceptions) - technical and organizational pretreatment methods and - posttreatment methods for residues mainly in the field of substance management - the present development, results of actual R and D plans and new trends are described. (orig.) [Deutsch] Der Bericht bietet einen Ueberblick ueber den aktuellen Entwicklungsstand der thermischen Abfallbehandlung und den weiteren Forschungsbedarf. Er nennt die Bedeutung der Vereinheitlichung rechtlicher Rahmenbedingungen in der europaeischen Abfallwirtschaft und Probleme, die aus der Internationalisierung der Abfallwirtschaft und der Umsetzung europaeischer Vorgaben in nationales Recht entstehen. In 19 Vortraegen und anschliessenden Diskussionen, deren Ergebnisse zusammengefasst gemeinsam mit den Vortragsmanuskripten dargestellt sind, werden - die Situation der (thermischen) Abfallbehandlung mehrerer europaeischer Staaten - die Technologien der - Siedlungsabfallverbrennung - alternativen thermischen Behandlungsverfahren - mechanisch-biologischen Restabfallbehandlung (in integrierten Behandlungskonzepten) - technischen und organisatorischen Vorbehandlungsmassnahmen und - Nachbehandlungsverfahren fuer Verbrennungsrueckstaende mit Schwerpunkt im Bereich des Stoffmanagements - die derzeitige Entwicklung

  13. Long-standing temporomandibular joint dislocation: A rare experience

    Directory of Open Access Journals (Sweden)

    Kapil Malik

    2017-01-01

    Full Text Available Long-standing temporomandibular joint (TMJ dislocations persist for more than a month are most challenging to treat. The management of such condition varies widely, from closed reduction to complicated surgical procedures. The choice of an appropriate methodology is questionable. At present, there are no standard rules or conventions for the ideal strategy in different circumstances. This paper attempts to present the experience of managing two cases of long-standing TMJ dislocations.

  14. ISSP Position Stand

    DEFF Research Database (Denmark)

    Ryba, Tatiana; Stambulova, Natalia; Si, Gangyan

    2013-01-01

    The multicultural landscape of contemporary sport sets a challenge to rethink sport and exercise psychology research and practice through a culturally re␣exive lens. This ISSP Position Stand provides a rigorous synthesis and engagement with existing scholarship to outline a roadmap for future work...... in the ␣eld. The shift to culturally competent sport and exercise psychology implies: (a) recognizing hidden ethnocentric philosophical assumptions permeating much of the current theory, research, and practice; (b) transitioning to professional ethics in which difference is seen as not inherent and ␣xed...... but as relational and ␣uid; and (c) focusing on meaning (instead of cause) in cross-cultural and cultural research projects, and cultural praxis work. In the paper, we ␣rst provide an overview of the concepts of cultural competence and ethics of difference. Second, we present a step-by-step approach for developing...

  15. Standing Concertation Committee

    CERN Multimedia

    HR Department

    2009-01-01

    The main items discussed at the meetings of the Standing Concertation Committee in the first quarter of 2009 included: Merit Appraisal and Recognition Scheme (MARS) 2009 exercise The committee took note of 2009 MARS ceiling guidelines giving the advancement budget by career path and amounting to approx 1.80% of the basic salary bill. To this will be added 250 steps CERN-wide, financed by savings from implementation of the international indemnity for 2007, 2008 and the first half of 2009. The specific Senior Staff Guidelines, including the proposed number of promotions from Career Path E to F, were also noted. The guidelines with respect to step distribution were also noted: the minima and maxima remain the same as in previous years. Compliance with the guidelines will continue to be monitored closely (more details, including a frequently asked questions section). It was also noted that Financial Awards (awards for extraordinary service and responsibility allowances) may b...

  16. STANDING CONCERTATION COMMMITTEE

    CERN Multimedia

    HR Department

    2008-01-01

    ORDINARY MEETING ON 27 FEBRUARY 2008 The main items discussed at the meetings of the Standing Concertation Committee on 27 February 2008 included: Short-term Saved Leave Scheme The committee noted that, by the end of February 2008, some 600 staff had subscribed to the short-term saved leave scheme: approx 58% had subscribed 1 slice, 14% two slices, 5% three slices and 23% four slices. Administrative Circular No. 4 (Rev. 4) - Unemployment Insurance Scheme The committee agreed to recommend Administrative Circular No. 4 (Rev. 4) - Unemployment Insurance Scheme to the Director-General for approval. Administrative Circular No. 30 (Rev. 2) - Financial benefits upon taking up appointment and termination of contract The committee agreed to recommend Administrative Circular No. 30 (Rev. 2) - Financial Benefits upon taking up appointment and termination of contract to the Director-General for approval. Progressive Retirement Programme The Progressive Retirement Programme (PRP) was extended for a further year to 3...

  17. Standing Concertation Committee

    CERN Document Server

    HR Department

    2008-01-01

    ORDINARY MEETING ON 27 FEBRUARY 2008 The main items discussed at the meetings of the Standing Concertation Committee on 27 February 2008 included: Short-term Saved Leave Scheme The Committee noted that, by the end of February 2008, some 600 staff had enrolled in the short-term saved leave scheme: approx. 58% had signed up for 1 slice, 14% for two slices, 5% for three slices and 23% for four slices. Administrative Circular No. 4 (Rev. 4) - Unemployment Insurance Scheme The Committee agreed to recommend the Director-General to approve Administrative Circular No. 4 (Rev. 4) - Unemployment Insurance Scheme. Administrative Circular No. 30 (Rev. 2) - Financial benefits upon taking up appointment and termination of contract The Committee agreed to recommend the Director-General to approve Administrative Circular No. 30 (Rev. 2) - Financial Benefits upon taking up appointment and termination of contract. Progressive Retirement Programme The Progressive Retirement Programme (PR...

  18. Structural attributes of stand overstory and light under the canopy

    Directory of Open Access Journals (Sweden)

    Alice Angelini

    2015-02-01

    Full Text Available  This paper reviews the literature relating to the relationship between light availability in the understory and the main qualitative and quantitative attributes of stand overstory usually considered in forest management and planning (species composition, density, tree sizes, etc. as well as their changes as consequences of harvesting. The paper is divided in two sections: the first one reviews studies which investigated the influence of species composition on understory light conditions; the second part examines research on the relationships among stand parameters determined from dendrometric field data and the radiation on understory layer. The objective was to highlight which are the most significant stand traits and management features to build more practical models for predicting light regimes in any forest stand and, in more general terms, to support forest managers in planning and designing silvicultural treatments that retain structure in different way in order to meet different objectives.

  19. Simulation of growth and competition in mixed stands of Douglas-fir and beech

    NARCIS (Netherlands)

    Bartelink, H.H.

    1998-01-01

    For a long time, the emphasis in silviculture in Western Europe was solely on even-aged, monospecific stands; many empirical stand-level growth models were developed and successfully used for managing such stands. In contrast, no generally accepted growth and yield approach has emerged so

  20. Effects of intermediate-severity disturbance on composition and structure in mixed Pinus-hardwood stands

    Science.gov (United States)

    Benjamin Trammell; Justin Hart; Callie Schweitzer; Daniel C. Dey; Michael Steinberg

    2017-01-01

    Increasingly, forest managers intend to create or maintain mixed Pinus-hardwood stands. This stand assemblage may be driven by a variety of objectives but is often motivated by the desire to enhance native forest diversity and promote resilience to perturbations. Documenting the effects of natural disturbances on species composition and stand...

  1. Complications of long-standing foreign body in the airway and their outcomes after endoscopic management: an experience of 20 cases.

    Science.gov (United States)

    Aggarwal, Satish Kumar; Sinha, Shandip Kumar; Ratan, Simmi K; Dhua, Anjan; Sethi, Gulshan Rai

    2015-01-01

    To study the outcomes after endoscopic treatment of chronic foreign bodies (FBs) in the airway. A retrospective study (2008-2013) of 20 cases with chronic airway FBs (>2 weeks) was done with emphasis on endoscopic management. All cases were initially evaluated by the pediatric pulmonologist. Flexible and rigid bronchoscopy was done for diagnosis and retrieval, respectively. The techniques of FB retrieval, problems encountered, and their solutions were analyzed. Follow-up flexible bronchoscopy was done in symptomatic cases. Outcomes were assessed in terms of successful removal of the FB, clinical recovery, lung expansion, and need for further procedures. Twenty cases (16 boys, 4 girls) with a mean age of 7 years had a chronic airway FB diagnosed on chest X-ray (n=6) and flexible bronchoscopy (n=14). Six cases had computed tomography evaluation. On rigid bronchoscopy, the FB was successfully retrieved in 16 cases. Two cases required open surgery for FB-induced tracheoesophageal fistula. One case required pneumonectomy because of a battery eroding into the lung parenchyma. One patient died. Of the 16 who had successful retrieval, 11 recovered with full lung expansion. Four recovered after additional bronchoscopic procedures (cauterization of granulation [n=2] and balloon dilatation of bronchial stenoses [n=2]). One case required pneumonectomy for persistent collapse despite multiple dilatations. An airway FB producing chronic respiratory symptoms may be missed because of lack of definite history of an inhaled FB. Clinical suspicion and flexible bronchoscopy are instrumental in diagnosis. Treatment is challenging because of chronicity-related complications and requires innovative ideas to make best use of the available urologic and bronchoscopic equipment. Addition of tracheotomy provides safety in difficult cases. Bronchoscopic removal leads to clinical and radiological recovery in most cases.

  2. Site establishment practices influence loblolly pine mortality throughout the stand rotation

    Science.gov (United States)

    Felipe G. Sanchez; Robert J. Eaton

    2010-01-01

    During a rotation, land managers need to estimate yields, update inventories, and evaluate stand dynamics. All of these factors in land management are heavily influenced by tree mortality. Tree mortality can, in turn, be influenced by land management practices from the inception of the stand and throughout the rotation. We describe the impact of organic matter removal...

  3. Information Entropy Measures for Stand Structural Diversity:Joint Entropy

    Institute of Scientific and Technical Information of China (English)

    Lei Xiangdong; Lu Yuanchang

    2004-01-01

    Structural diversity is the key attribute of a stand. A set of biodiversity measures in ecology was introduced in forest management for describing stand structure, of which Shannon information entropy (Shannon index) has been the most widely used measure of species diversity. It is generally thought that tree size diversity could serve as a good proxy for height diversity. However, tree size diversity and height diversity for stand structure is not completely consistent. Stand diameter cannot reflect height information completely. Either tree size diversity or height diversity is one-dimensional information entropy measure. This paper discussed the method of multiple-dimensional information entropy measure with the concept of joint entropy. It is suggested that joint entropy is a good measure for describing overall stand structural diversity.

  4. Impacto do manejo de resíduos orgânicos durante a reforma de plantios de eucalipto sobre indicadores de qualidade do solo Impact of organic residue management on soil quality indicators during replanting of eucalypt stands

    Directory of Open Access Journals (Sweden)

    Guilherme Montandon Chaer

    2007-12-01

    priorizaram a conservação dos resíduos orgânicos por ocasião da reforma do povoamento. Contrariamente, as áreas onde ocorreu a remoção ou a queima do material orgânico da superfície do solo foram as que mais se distanciaram da área de referência. Esses resultados demonstram que o sistema de manejo adotado na reforma dos povoamentos de eucalipto analisados influencia, em médio prazo, o potencial dos solos de estocar e ciclar nutrientes por meio da biomassa microbiana e das atividades bioquímicas ligadas a ela. A maior aproximação entre a área com vegetação nativa e a de eucalipto com 11 anos leva a supor que ciclos mais longos nas florestas de eucalipto, contrastando com o padrão atualmente em uso no Brasil (cerca de sete anos, pode ser relevante para se manter a sustentabilidade da atividade florestal em longo prazo, a despeito de uma menor produtividade média anual. Nesse caso, a opção pela produtividade de curto ou médio prazo, ou pela sustentabilidade do uso do solo, com a conseqüente manutenção da sua qualidade para as gerações futuras, poderá ser repensada a partir dos dados aqui apresentados.Agricultural soil use induces changes in soil physical, chemical, and microbiological characteristics. These changes can eventually lead to a loss of soil quality and a consequent reduction in plant growth and productivity. The analysis of biochemical and microbiological soil quality indicators is relevant to monitor changes in soil quality and in the performance of key soil functions, such as the capacity of nutrient cycling and storage. This study reports on physical, chemical, and biochemical/microbiological quality indicators of soil under eucalyptus plantation, evaluated 5.5 years after the site had undergone different management practices during stand replanting. Evaluations were based on the determination of 18 physical or chemical besides 12 biochemical or microbiological attributes that are considered soil quality indicators. The

  5. Standing Concertation Committee

    CERN Multimedia

    2007-01-01

    Ordinary meeting on 30 January 2007 The main items discussed at the meeting of the Standing Concertation Committee on 30 January 2007 included: Administrative Circular No. 26: with the introduction of the merit recognition system in the framework of the 5-yearly review of CERN employment conditions, Administrative Circular No. 26 has been revised. The committee took note of the revised document which is being finalized for submission to the Director-General for approval in the near future. Technical analysis of CERN Health Insurance Scheme: the Committee was informed that a group has been set up by the Director-General to analyse the financial situation of the CERN Health Insurance Scheme in the short and long term, and to propose measures to ensure that the Scheme remains in financial balance, with adequate cover, over the medium term. The group's terms of reference and membership were communicated. Voluntary programmes It was announced that the programmes: 'part-time work as a pre-retirement measure...

  6. Standing Concertation Committee

    CERN Multimedia

    2007-01-01

    ORDINARY MEETING ON 30 JANUARY 2007 The main items discussed at the meeting of the Standing Concertation Committee on 30 January 2007 included: Administrative Circular No. 26: with the introduction of the merit recognition system in the framework of the 5-yearly review of CERN employment conditions, Administrative Circular No. 26 has been revised. The Committee took note of the revised document which is being finalized for submission to the Director-General for approval in the near future. Technical analysis of CERN Health Insurance Scheme: the Committee was informed that a group has been set up by the Director-General to analyse the financial situation of the CERN Health Insurance Scheme in the short and long term, and to propose measures to ensure that the Scheme remains in financial balance, with adequate cover, over the medium term. The group's terms of reference and membership were communicated. Voluntary programmes It was announced that the programmes: 'part-time work as a pre-retirement mea...

  7. Standing concertation commmittee

    CERN Multimedia

    HR Department

    2009-01-01

    MEETINGS ON 2 AND 9 DECEMBER 2008 The main items discussed at the meetings of the Standing Concertation Committee on 2 and 9 December 2008 included: Medical Service Report 2007 The Committee took note of the report by Dr. E. Reymond (see http://sc-me.web.cern.ch/sc-me/fr/indexFR.htm) and of a number of points raised during the discussion. It was noted that the number of professional accidents declined in 2007 (361 accidents) in comparison with 2006 (483), as well as their gravity and frequency. The CERN Medical Service carried out a study on cancer prevalence (number of cases) and incidence (new cases per year per 100000 people), between 1993 and 2007, which identified some prostate, breast and colorectal cancers, though less than in the two Host States. Specific preventive actions will be promoted by the CERN CHISboard and the Medical Service in this context as well as in other areas. The committee expressed its thanks to all members of the Medical Service for their work i...

  8. Dynamics of Connecticut hemlock stands

    Science.gov (United States)

    Jeffrey S. Ward; David M. Smith

    2000-01-01

    The stand dynamics and production of two one-acre plots of eastern hemlock (Tsuga canadensis L) in Connecticut have been followed for more than six decades. Data were recorded for all individual trees. One plot (Saltonstall) was established in 1924 after the removal of a hardwood overstory. This stand had a nearly pure, almost fully closed understory...

  9. A Cryogenic Test Stand for Large Superconducting Solenoid Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Rabehl, R. [Fermilab; Carcagno, R. [Fermilab; Nogiec, J. [Fermilab; Orris, D. [Fermilab; Soyars, W. [Fermilab; Sylvester, C. [Fermilab

    2013-01-01

    A new test stand for testing large superconducting solenoid magnets at the Fermilab Central Helium Liquifier (CHL) has been designed, and operated. This test stand has been used to test a coupling coil for the Muon Ionization Cooling Experiment (MICE), and future uses include solenoids for the Fermilab mu2e experiment. This paper describes the test stand design and operation including controlled cool-down and warm-up. Overviews of the process controls system and the quench management system are also included.

  10. Cutting mountain hardwood stands

    Science.gov (United States)

    Ralph W. Marquis; Sidney Weitzman; Carl J. Holcomb

    1954-01-01

    On the Fernow Experimental Forest in West Virginia, as on several other experimental forests in the Northeast, studies are being conducted to compare the biologic and economic results of different methods of forest management. The experiments are being carried out on compartments varying in size from 50 t o 150 acres. Such areas are large enough to permit the...

  11. Quantitative Analysis of Complex Tropical Forest Stands: A Review ...

    African Journals Online (AJOL)

    The importance of data analysis in quantitative assessment of natural resources remains significant in the sustainable management of complex tropical forest resources. Analyses of data from complex tropical forest stands have not been easy or clear due to improper data management. It is pivotal to practical researches ...

  12. Economic evaluation of intermediate operations in oak stands

    Science.gov (United States)

    Henry H. Webster; John C., Jr. Meadows

    1971-01-01

    Economic evaluation of forest-management opportunities is a vital ingredient of effective forestry programs. Choices among management opportunities are necessary because opportunities inevitably exceed funds available, and they are important because opportunities commonly range from highly productive to decidedly unproductive. Economic evaluation in oak stands shows a...

  13. Non-spray spruce budworm management alternatives: Will thinning second-growth balsam fir in northwestern Ontario alter the stands` vulnerability to spruce budworm damage. NWOFTDU technical report No. 53

    Energy Technology Data Exchange (ETDEWEB)

    Van Schip, W.M.; Towill, W.D.; Zago, T.

    1990-12-31

    The objective of this study was to determine whether balsam fir stands, thinned to different levels of basal area, differ in their susceptibility and vulnerability to damage created by infestations of spruce budworm. In 1976-77, the investigators thinned two relatively pure, juvenile, second-growth balsam fir stands in northwestern Ontario to four levels of basal area by girdling or felling. The stands were assessed in 1988. Annual aerial and ground monitoring of the study sites indicated that one area experienced a moderate to severe defoliation by spruce budworm during 1984-86, while the other area experienced moderate to severe defoliation by budworm during 1980-86. This report presents results of the study and discusses the relation between thinning, budworm damage, and stand productivity.

  14. Silvicultural interpretation of natural vegetation dynamics in ageing Scots pine stands for their conversion into mixed broadleaved stands

    NARCIS (Netherlands)

    Kint, V.; Geudens, G.; Mohren, G.M.J.; Lust, N.

    2006-01-01

    In many West-European regions there is principal consensus on the conversion of homogeneous even-aged Scots pine plantations into mixed broadleaved stands. In recent years, interest is growing for conversion management in which managers try to maximise the use of natural processes by steering or

  15. Solar Charged Stand Alone Inverter

    OpenAIRE

    M.Vasugi; Prof R.Jayaraman

    2014-01-01

    This paper deals with solar powered stand alone inverter which converts the variable dc output of a photovoltaic solar panel into ac that can be fed to loads. Stand alone inverters are used in systems where the inverter get its energy from batteries charged by photo voltaic arrays. A charge controller limits the rate at which electric current is added to or drawn from electric batteries. This charge discharge controller is needed to prevent the battery from being overcharged o...

  16. STANDING CONCERTATION COMMITTEE

    CERN Multimedia

    2003-01-01

    ORDINARY MEETING ON 29 SEPTEMBER 2003 Original: English This meeting was devoted to the main topics summarised below. 1 Follow-up from the meetings of TREF and the Finance Committee in September 2003 The last meeting of TREF had been devoted to presentations and clarifications on the 5-Yearly Review process. The content and planning of the 2005 Review are matters for the next Management, which will be presented to TREF next year. Underlining that due account has to be taken of the limited resources available to conduct such an exercise, the Staff Association stated that it looks forward to the concertation process at the SCC in preparing the next 5-Yearly Review to define an optimum set of topics in order to ensure that CERN can attract, retain and motivate the personnel that it needs to remain a centre of excellence. The Chairman of the SCC recalled that an information document on the Cost-Variation Index for 2004 had been transmitted to the Finance Committee last September and that complete information o...

  17. Isotope separation by standing waves

    International Nuclear Information System (INIS)

    Altshuler, S.

    1984-01-01

    The separation of isotopes is accomplished by scattering a beam of particles from a standing electromagnetic wave. The particles may consist of either atoms or molecules, the beam having in either case a desired isotope and at least one other. The particle beam is directed so as to impinge on the standing electromagnetic wave, which may be a light wave. The particles, that is, the atomic or molecular quantum-mechanical waves, see basically a diffraction grating corresponding to the troughs and peaks of the electromagnetic wave. The frequency of the standing electromagnetic wave substantially corresponds to an internal energy level-transition of the desired isotope. Accordingly, the desired isotope is spatially separated by being scattered or diffracted. (author)

  18. Residual Liquefaction under Standing Waves

    DEFF Research Database (Denmark)

    Kirca, V.S. Ozgur; Sumer, B. Mutlu; Fredsøe, Jørgen

    2012-01-01

    This paper summarizes the results of an experimental study which deals with the residual liquefaction of seabed under standing waves. It is shown that the seabed liquefaction under standing waves, although qualitatively similar, exhibits features different from that caused by progressive waves....... The experimental results show that the buildup of pore-water pressure and the resulting liquefaction first starts at the nodal section and spreads towards the antinodal section. The number of waves to cause liquefaction at the nodal section appears to be equal to that experienced in progressive waves for the same...

  19. Stand development and population dynamics of curlleaf mountain mahogany (Cercocarpus ledifolius Nutt.) woodlands in Utah's Bear River Mountains

    Science.gov (United States)

    Seth A. Ex; Robert DeRose; James N. Long

    2011-01-01

    Curlleaf mountain mahogany (Cercocarpus ledifolius Nutt.) is a little-studied woodland tree that occurs in pure stands throughout the Intermountain West. Stand development and population dynamics of this species are poorly understood, despite their relevance to management. We describe here the development of stand age structures and population dynamics of mahogany...

  20. Burnout : de stand van zaken

    NARCIS (Netherlands)

    Taris, T.; Houtman, I.L.D.; Schaufeli, W.

    2013-01-01

    Dit artikel geeft een overzicht van de stand van zaken in het onderzoek naar burnout. Burnout is een syndroom van extreme vermoeidheid (uitputting), afstand nemen van het werk (distantie) en weinig vertrouwen in het eigen kunnen (verminderde competentie), waarbij de oorzaken voor deze aspecten

  1. Southern pine beetle in loblolly pine: simulating within stand interactions using the process model SPBLOBTHIN

    Science.gov (United States)

    Brian Strom; J. R. Meeker; J. Bishir; James Roberds; X. Wan

    2016-01-01

    Pine stand density is a key determinant of damage resulting from attacks by the southern pine beetle (SPB, Dendroctonus frontalis Zimm.). High-density stands of maturing loblolly pine (Pinus taeda L.) are at high risk for losses to SPB, and reducing stand density is the primary tool available to forest managers for preventing and mitigating damage. Field studies are...

  2. Forest stand dynamics of shortleaf pine in the Ozarks

    Science.gov (United States)

    David R. Larsen

    2007-01-01

    Much has been written on the management of shortleaf pine in the Ozarks (Brinkman et al. 1965, Brinkman 1967, Brinkman and Smith 1968, Seidel and Rogers 1965, Seidel and Rogers 1966). In large portions of the Ozarks, shortleaf pine does not grow in pure stands but rather in mixes with various oak species. These mixes present unique challenges in finding the set of...

  3. Stand up and move forward

    OpenAIRE

    de Jong, Johan; Shokoohi, Roya

    2017-01-01

    Insufficient physical activity or being inactive is one of the leading risk factors for non-communicable diseases worldwide. Globally between 6-10% of premature mortality, caused by non-communicable diseases, could be avoided if people adhered to general physical activity guidelines. Besides that, studies link sitting for prolonged periods of time with many serious health concerns. The solution seems simple: Stand up and move forward. However, human behavior is difficult to change – due to th...

  4. A whole stand growth and yield system for young longleaf pine plantations in Southwest Georgia

    Science.gov (United States)

    John R. Brooks; Steven B. Jack

    2006-01-01

    A whole stand growth and yield system for planted longleaf pine (Pinus palustris Mill.) was developed from permanent plot data collected annually over an 8 year period. The dataset consists of 12 intensively-managed longleaf pine plantations that are located in Lee, Worth, Mitchell, and Baker counties in southwest Georgia. Stand survival, dominant...

  5. Clonal Spread in Second Growth Stands of Coast Redwood, Sequoia sempervirens

    Science.gov (United States)

    Vladimir Douhovnikoff; Richard S. Dodd

    2007-01-01

    Coast redwood (Sequoia sempervirens) is one of the rare conifers to reproduce successfully through clonal spread. The importance of this mode of reproduction in stand development is largely unknown. Understanding the importance of clonal spread and the spatial structure of clones is crucial for stand management strategies that would aim to maximize...

  6. Modelling growth and water use in four Pinus patula stands with the ...

    African Journals Online (AJOL)

    Existing prediction models do not take sufficient stand and site detail into account to usefully predict water use patterns on a scale that is practical to forest managers. Several relatively simple simulation models based on the major physiological processes behind growth and water use of forest stands have emerged recently, ...

  7. Object-oriented classification of forest structure from light detection and ranging data for stand mapping

    Science.gov (United States)

    Alicia A. Sullivan; Robert J. McGaughey; Hans-Erik Andersen; Peter. Schiess

    2009-01-01

    Stand delineation is an important step in the process of establishing a forest inventory and provides the spatial framework for many forest management decisions. Many methods for extracting forest structure characteristics for stand delineation and other purposes have been researched in the past, primarily focusing on high-resolution imagery and satellite data. High-...

  8. Transpalpebral eye enucleation in the standing horse

    DEFF Research Database (Denmark)

    Christophersen, Mogens Teken

    Transpalpebral eye enucleation in the standing horse. The Nordic Equine Veterinary Conference, Proceedings, Copenhagen. Denmark. Nov. 2011.......Transpalpebral eye enucleation in the standing horse. The Nordic Equine Veterinary Conference, Proceedings, Copenhagen. Denmark. Nov. 2011....

  9. Compatible growth models and stand density diagrams

    International Nuclear Information System (INIS)

    Smith, N.J.; Brand, D.G.

    1988-01-01

    This paper discusses a stand average growth model based on the self-thinning rule developed and used to generate stand density diagrams. Procedures involved in testing are described and results are included

  10. 24 CFR 206.37 - Credit standing.

    Science.gov (United States)

    2010-04-01

    ... CONVERSION MORTGAGE INSURANCE Eligibility; Endorsement Eligible Mortgagors § 206.37 Credit standing. Each mortgagor must have a general credit standing satisfactory to the Secretary. ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Credit standing. 206.37 Section 206...

  11. [Soil quality assessment of forest stand in different plantation esosystems].

    Science.gov (United States)

    Huang, Yu; Wang, Silong; Feng, Zongwei; Gao, Hong; Wang, Qingkui; Hu, Yalin; Yan, Shaokui

    2004-12-01

    After a clear-cutting of the first generation Cunninghamia lanceolata plantation in 1982, three plantation ecosystems, pure Michelia macclurei stand (PMS), pure Chinese-fir stand (PCS) and their mixed stand, were established in spring 1983, and their effects on soil characteristics were evaluated by measuring some soil physical, chemical, microbiological and biochemical parameters. After 20 years' plantation, all test indices showed differences among different forest management models. Both PMS and MCM had a favorable effect on soil fertility maintenance. Soil quality assessment showed that some soil functions, e.g., water availability, nutrient availability, root suitability and soil quality index were all in a moderate level under the mixed and pure PMS stands, whereas in a relatively lower level under successive PCS stand. The results also showed that there existed close correlations between soil total organic C (TOC), cation exchange capacity (CEC), microbial biomass-C (Cmic) and other soil physical, chemical and biological indices. Therefore, TOC, CEC and Cmic could be used as the indicators in assessing soil quality in this study area. In addition, there were also positive correlations between soil microbial biomass-C and TOC, soil microbial biomass-N and total N, and soil microbial biomass-P and total P in the present study.

  12. The one-leg standing radiograph

    OpenAIRE

    Pinsornsak, P.; Naratrikun, K.; Kanitnate, S.; Sangkomkamhang, T.

    2016-01-01

    Objectives The purpose of this study was to compare the joint space width between one-leg and both-legs standing radiographs in order to diagnose a primary osteoarthritis of the knee. Methods Digital radiographs of 100 medial osteoarthritic knees in 50 patients were performed. The patients had undergone one-leg standing anteroposterior (AP) views by standing on the affected leg while a both-legs standing AP view was undertaken while standing on both legs. The severity of the osteoarthritis wa...

  13. Effects on musculoskeletal pain from “Take a stand!”

    DEFF Research Database (Denmark)

    Danquah, Ida Høgstedt; Kloster, Stine; Holtermann, Andreas

    2017-01-01

    a Stand! included 19 offices (317 workers) at four workplaces cluster randomized to intervention or control. The multicomponent intervention lasted three months and included management support, environmental changes, and local adaptation. Control participants behaved as usual. Musculoskeletal pain...

  14. Multiple diseases impact survival of pine species planted in red spine stands harvested in spatially variable retention patterns

    Science.gov (United States)

    M.E. Ostry; M.J. Moore; C.C. Kern; R.C. Venette; B.J. Palik

    2012-01-01

    Increasing the diversity of species and structure of red pine (Pinus resinosa) is often a management goal in stands simplified by practices such as fire suppression and plantation management in many areas of the Great Lakes Region. One approach to diversification is to convert predominantly even-aged, pure red pine stands to multi-cohort, mixed-...

  15. Fungal diseases of tree stands under urbanized conditions of Moscow

    Directory of Open Access Journals (Sweden)

    Smirnova Oksana G.

    2013-01-01

    Full Text Available Phytosanitary and ecological estimation of tree-stands has been con­ducted at the Forest Experimental Station of Moscow Agricultural Academy and parks of Northeast of Moscow in 2007-2011. Fomes fomentarius was proved to be a very serious pathogen of trees under conditions of Moscow, Piptoporus betulinus, Phellinus igniarius, and Fomitopsis pinicola also occurred and caused damage to trees. This rather bad phytosanitary situation depends on alarming ecological situation in Moscow. At the Forest Experimental Station of Moscow Agricultural Academy a number and cover of lichens decreased. In general, all trees in Moscow are in dynamic equilibrium with the urbanized environment. In connection with this, the following classification of tree-stands was proposed for the urbanized environment: 1 - healthy trees, 2 - affected trees which can be managed, 3 - dry woods, 3a - very diseased. Many tree-stands in investigated regions of Moscow are found to belong to the groups 2 and 3c. All tree-stands must be carefully monitored and managed in order to provide a well-timed decision on the support system for preservation of trees as ‘lungs of city’ and avoid unpredictable tree falling which put people and traffic at risk.

  16. Woodland: dynamics of average diameters of coniferous tree stands of the principal forest types

    Directory of Open Access Journals (Sweden)

    R. A. Ziganshin

    2016-08-01

    Full Text Available The analysis of age dynamics of average diameters of deciduous tree stands of different forest types at Highland Khamar-Daban (natural woodland in South-East Baikal Lake region has been done. The aggregate data of average tree, the analysis of age dynamics of average diameters of a deciduous tree stands of stand diameters by age classes, as well as tree stand current periodic and overall average increment are presented and discussed in the paper. Forest management appraisal is done. The most representative forest types have been selected to be analyzed. There were nine of them including three Siberian stone pine Pinus sibirica Du Tour stands, three Siberian fir Abies sibirica Ledeb. stands, one Siberian spruce Picea obovata Ledeb. stand, and two dwarf Siberian pine Pinus pumila (Pallas Regel stands. The whole high-altitude range of mountain taiga has been evaluated. Mathematical and statistic indicators have been calculated for every forest type. Stone pine stands are the largest. Dynamics of mean diameters of forest stands have been examined by dominant species for every forest type. Quite a number of interesting facts have been elicited. Generally, all species have maximal values of periodic annual increment that is typical for young stands, but further decrease of increment is going on differently and connects to the different lifetime of wood species. It is curious that annual increment of the dwarf Siberian pine stands almost does not decrease with aging. As for mean annual increment, it is more stable than periodic annual increment. From the fifth age class (age of stand approaching maturity mean annual increment of cedar stands varies from 0.20 to 0.24 cm per year; from 0.12–0.15 to 0.18–0.21 cm per year – in fir stands; from 0.18 to 0.24 cm per year – in spruce stands; and from 0.02–0.03 to 0.05–0.06 cm per year – in draft pine stands. Mean annual increment of dwarf Siberian pine increases with aging and increment of other

  17. Effects of two-age management and clearcutting on songbird density and reproductive success

    Science.gov (United States)

    Jeffery V. Nichols; Petra Bohall Wood

    1995-01-01

    We examined density and reproductive success of passerine species on 7 uncut forest stands and on 12 stands harvested 10-14 years ago on the Monongahela National Forest of West Virginia (6 clearcut stands and 6 stands harvested using 2-age management). In 2-age management, stands resemble a shelterwood cut with 10-30 overstory trees/acre left uncut. Uncut periphery...

  18. Refrigeration system having standing wave compressor

    Science.gov (United States)

    Lucas, Timothy S.

    1992-01-01

    A compression-evaporation refrigeration system, wherein gaseous compression of the refrigerant is provided by a standing wave compressor. The standing wave compressor is modified so as to provide a separate subcooling system for the refrigerant, so that efficiency losses due to flashing are reduced. Subcooling occurs when heat exchange is provided between the refrigerant and a heat pumping surface, which is exposed to the standing acoustic wave within the standing wave compressor. A variable capacity and variable discharge pressure for the standing wave compressor is provided. A control circuit simultaneously varies the capacity and discharge pressure in response to changing operating conditions, thereby maintaining the minimum discharge pressure needed for condensation to occur at any time. Thus, the power consumption of the standing wave compressor is reduced and system efficiency is improved.

  19. Dynamics models and modeling of tree stand development

    Directory of Open Access Journals (Sweden)

    M. V. Rogozin

    2015-04-01

    Full Text Available Brief analysis of scientific works in Russia and in the CIS over the past 100 years. Logical and mathematical models consider the conceptual and show some of the results of their verification. It was found that the models include different laws and the parameters, the sum of which allows you to divide them into four categories: models of static states, development models, models of care for the natural forest and models of cultivation. Each category has fulfilled and fulfills its tasks in economic management. Thus, the model states in statics (table traverse growth played a prominent role in figuring out what may be the most productive (full stands in different regions of the country. However, they do not answer the question of what the initial states lead to the production of complete stands. In a study of the growth of stands used system analysis, and it is observed dominance of works studying static state, snatched from the biological time. Therefore, the real drama of the growth of stands remained almost unexplored. It is no accident there were «chrono-forestry» «plantation forestry» and even «non-traditional forestry», where there is a strong case of a number of new concepts of development stands. That is quite in keeping with Kuhn (Kuhn, 2009 in the forestry crisis began – there were alternative theories and coexist conflicting scientific schools. To develop models of stand development, it is proposed to use a well-known method of repeated observations within 10–20 years, in conjunction with the explanation of the history of the initial density. It mounted on the basis of studying the dynamics of its indicators: the trunk, crown overlap coefficient, the sum of volumes of all crowns and the relative length of the crown. According to these indicators, the researcher selects natural series of development stands with the same initial density. As a theoretical basis for the models it is possible to postulate the general properties of

  20. Effects of stand composition and thinning in mixed-species forests : a modeling approach applied to Douglas-fir and beech

    NARCIS (Netherlands)

    Bartelink, H.H.

    2000-01-01

    Models estimating growth and yield of forest stands provide important tools for forest management. Pure stands have been modeled extensively and successfully for decades; however, relatively few models for mixed-species stands have been developed. A spatially explicit, mechanistic model (COMMIX) is

  1. GENERAL ASSESMENT OF SEED STANDS OF ORIENTAL SPRUCE (Picea orientalis L. Link.

    Directory of Open Access Journals (Sweden)

    İbrahim Turna

    2001-04-01

    Full Text Available The seeds for afforestation studies with oriental spruce (Picea orientalis L.Link. populations are usually gathered from already established seed stands. This study showed that most of the seed stands were not selected appropriately and some of them were not properly protected and maintained when evaluated according to the “criteria for selection and management of seed stands”. The average slope of seed stands was as high as 43% and the average size varied from 33.5 ha to 147.5 ha Since the stands were open to social disturbances and wind effects, the number of trees per ha decreased 51% and the number of seed trees dropped to a level of 56%. In conclusion, seeds collected from poorly established seed stands will likely jeopardize the success in reforestation studies in the future.

  2. Reineke’s stand density index: a quantitative and non-unitless measure of stand density

    Science.gov (United States)

    Curtis L. VanderSchaaf

    2013-01-01

    When used as a measure of relative density, Reineke’s stand density index (SDI) can be made unitless by relating the current SDI to a standard density but when used as a quantitative measure of stand density SDI is not unitless. Reineke’s SDI relates the current stand density to an equivalent number of trees per unit area in a stand with a quadratic mean diameter (Dq)...

  3. The Stand-alone Heliostat

    International Nuclear Information System (INIS)

    Garcia Navajas, G. I.; Egea Gea, A.

    2000-01-01

    The first Autonomous Heliostat has been developed by CIEMAT at PSA facilities in Almeria. This heliostat is an innovative approach to reducing the civil engineering work costs in heliostat fields of central tower plants. Channels, cables and other electric elements have been eliminated in the new heliostat. Thus, one 70-nr, classical T glass/metal heliostat has been adapted to include all the new stand-alone concept components. A PV system is able to drive two sun-tracking DC motors between 5 and 24Vdc, 0 and 15A. The heliostat communicates with the control room 400-m away by using a radio-modem working at 9600 baud. An anemometer, a wind switcher, light and ambient temperature sensors have been installed on the heliostat for self-protection decision-making. A PV panel integrated into the heliostat reflecting surface, eliminates cabling and other elements required for a conventional power supply. Communication lines between master control and local control have been replaced by radio-modem. Testing has validated the technical feasibility of the prototype and quantified the real consumption and efficiencies of new elements. The extra costs produced.by the autonomous concepts are compared with the cost of civil work in conventional heliostat field. (Author) 8 refs

  4. SPEED ROLLER STAND MEASUREMENT SYSTEM CHECKING TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Y. Zybtsev

    2011-01-01

    Full Text Available The study has shown that the accuracy of brakes checking by inertial stands depends upon the applied methods of measurement of braking parameters (stand slowing down, braking distance, brakes triggering time, current speed as well as the methods of metrological checking of measuring system canals.

  5. Evaluating growth performance of young stands

    Science.gov (United States)

    A. L. Roe; R. E. Benson

    1966-01-01

    A simple procedure for evaluating the diameter growth of young stands in relation to potential growth is described. A comparison technique is developed which contrasts relative diameter of crop trees to the relative diameter growth of the last decade to show the condition and trend of growth in the stand. The method is objective, easy to use, and has several...

  6. Harvesting budworm-damaged stands for fuel

    Energy Technology Data Exchange (ETDEWEB)

    Henley, S.G. (York, Sunbury, Charlotte Wood Products Marketing Board, (Canada))

    1985-01-01

    This project was initiated to demonstrate the economics and logistics of harvesting budworm-damaged stands for use as fuel. Dead spruce and balsam fir were to be harvested from small private woodlots in southwestern New Brunswick, using an integrated, full-tree harvesting system to produce wood chip fuel and other forest products. The overall objectives of the study are listed. The harvesting equipment and the selection of sites are discussed. The most efficient methods of finding candidate woodlots was found to be by advertising and word of mouth. Contact was made with 85 woodlot owners, and 45 woodlots were visited and evaluated for their suitability. A further 150 management plans were screened and rejected for various reasons. Only 2 woodlots were initially recognized as potential sites; however, after showing some interest, the owners decided not to participate. The reasons for the rejection of the various woodlots are listed. The fact that a number of owners were against clearcutting, and, in some cases, against any cutting, and that others showed no interest in the study, is attributed to the high percentage of white-collar workers owning woodlots. Other strategies for harvesting dead or scrap wood are suggested. 1 ref., 1 tab.

  7. Key processes from tree to stand level

    International Nuclear Information System (INIS)

    Hinckley, T.; Ford, D.; Segura, G.; Sprugel, D.

    1991-01-01

    Changes in six factors have been identified as having potential major future impacts on the productivity and survival of forest trees and stands. These factors are atmospheric carbon dioxide concentration, tropospheric ozone concentration, mean annual air temperature and precipitation, extremes in temperature and precipitation, and levels of ultraviolet radiation. Except for precipitation, all of these factors are expected to increase with climatic change. However, the likelihood of their increase or change ranges from the given to the unknown. The way in which one or more of these factors might individually or in combination affect the productivity and survival of trees is discussed, and particularly sensitive physiological processes are identified. For example, increases in winter temperature and a doubling of CO 2 will result in early budburst in many species and therefore increase the risk of frost damage. In other species or locations, warm winters may mean insufficient chilling hours and the requirements for release from bud dormancy may not be met. The interaction of these processes with current species distribution, genotype selection, and management alternatives is reviewed. 52 refs., 1 fig., 1 tab

  8. Financial Village Standing in Indonesian Financial System

    Directory of Open Access Journals (Sweden)

    Herry Purnomo

    2015-12-01

    Full Text Available Financial resources of the village that are sourced from a country or a Regional Finance Financial based Law Number 6 Year 2014 of The Village is the mandate of the law that must be allocated to the village. The interconnectedness of the financial position of the village in the financial system of the country or Region concerned the Financial administrative and territorial relations, and there is no setting directly regarding the finances of the village as part of the financial system of the country or the financial area. In respect of the elements of the crime of corruption deeds against financial irregularities of the village there are still disagreements on the interpretation of the law in trapping the perpetrators of corruption on the village chief that implies not satisfy the principle of legality and legal certainty in the ruling of the matter of financial irregularities. In fact, many of the village chief or Councilor caught the criminal offence of corruption over the use of financial irregularities. This research analyzes How the financial position of the village in the financial system of the country or region, as well as whether the financial resources of the village is derived from the state budget or region budget managed in village budget belongs to the category of village finances and whether tort against the financial management of the village can be categorized as a criminal act corruption. How To Cite: Purnomo, H. (2015. Financial Village Standing in Indonesian Financial System. Rechtsidee, 2(2, 121-140. doi:http://dx.doi.org/10.21070/jihr.v2i2.81

  9. Introducing sit-stand desks increases classroom standing time among university students

    Directory of Open Access Journals (Sweden)

    Matthew Jerome

    2017-12-01

    Full Text Available Excessive sedentary behavior has been associated with many negative health outcomes. While an understudied health topic, there is evidence that university students are excessively sedentary. Sit-stand desks have been shown to reduce sedentary time among pre-university students (ages 5–18years and sedentary workers but have not been tested in university classrooms. This study tested the effects of introducing sit-stand desks into a university classroom on student's classroom sitting and standing behaviors. Using a cross-over design, students received access to both traditional seated desks and sit-stand desks for six weeks. Data were collected between September and December, 2016. We recruited 304 healthy undergraduate university students enrolled in one of two small (25 seats classrooms at a large Midwestern university during the fall of 2016. Average minutes of standing/hour/student, average percent class time spent standing, and the number of sit-stand transitions/student/hour were directly observed with video camera surveillance. Participants stood significantly more (p<0.001 when provided access to sit-stand desks (7.2min/h/student; 9.3% of class time spent standing compared to when they had access to seated desks (0.7min/h/student; 1.6% of class time spent standing but no differences were observed for the number of sit-stand transitions (p=0.47. Students reported high favorability for the sit-stand desks and improvements in several student engagement and affective outcomes while using the sit-stand desks. These findings support introducing sit-stand desks in university classrooms as an approach to reduce sedentary behaviors of university students. Keywords: Sedentary, University students, Sit-stand desk

  10. Stand age and climate drive forest carbon balance recovery

    Science.gov (United States)

    Besnard, Simon; Carvalhais, Nuno; Clevers, Jan; Herold, Martin; Jung, Martin; Reichstein, Markus

    2016-04-01

    Forests play an essential role in the terrestrial carbon (C) cycle, especially in the C exchanges between the terrestrial biosphere and the atmosphere. Ecological disturbances and forest management are drivers of forest dynamics and strongly impact the forest C budget. However, there is a lack of knowledge on the exogenous and endogenous factors driving forest C recovery. Our analysis includes 68 forest sites in different climate zones to determine the relative influence of stand age and climate conditions on the forest carbon balance recovery. In this study, we only included forest regrowth after clear-cut stand replacement (e.g. harvest, fire), and afforestation/reforestation processes. We synthesized net ecosystem production (NEP), gross primary production (GPP), ecosystem respiration (Re), the photosynthetic respiratory ratio (GPP to Re ratio), the ecosystem carbon use efficiency (CUE), that is NEP to GPP ratio, and CUEclimax, where GPP is derived from the climate conditions. We implemented a non-linear regression analysis in order to identify the best model representing the C flux patterns with stand age. Furthermore, we showed that each C flux have a non-linear relationship with stand age, annual precipitation (P) and mean annual temperature (MAT), therefore, we proposed to use non-linear transformations of the covariates for C fluxes'estimates. Non-linear stand age and climate models were, therefore, used to establish multiple linear regressions for C flux predictions and for determining the contribution of stand age and climate in forest carbon recovery. Our findings depicted that a coupled stand age-climate model explained 33% (44%, average site), 62% (76%, average site), 56% (71%, average site), 41% (59%, average site), 50% (65%, average site) and 36% (50%, average site) of the variance of annual NEP, GPP, Re, photosynthetic respiratory ratio, CUE and CUEclimax across sites, respectively. In addition, we showed that gross fluxes (e.g. GPP and Re) are

  11. Juvenile offenders: competence to stand trial.

    Science.gov (United States)

    Soulier, Matthew

    2012-12-01

    This article details the legal background and assists the reader in the preparation and practical conduct of evaluations regarding juvenile adjudicative competency. The material is presented to be useful as a guide to direct questions of competency and covers aspects of evaluation that include: legal standard for competency to stand trial, developmental immaturity, current practice in juvenile competency to stand trial, forensic evaluation of juvenile competency to stand trial, organizing the evaluation, collateral sources of information, psychiatric evaluation of juvenile adjudicative competency, assessment of mental disorder and intellectual disability, assessment of developmental status, assessment of functional abilities for adjudicative competence, and reaching the forensic opinion. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Recent advances in standing equine orthopedic surgery.

    Science.gov (United States)

    O'Brien, Thomas; Hunt, Robert J

    2014-04-01

    In all surgeries with the patient standing under chemical and physical restraint, patient compliance is of the utmost importance. All fractures of the third metacarpal or metatarsal condyles and sagittal fracture of the first phalanx are not amenable to internal fixation with the horse standing, and young unhandled horses may not have a suitable disposition for standing surgical treatment of septic pedal osteitis, or implantation and removal of transphyseal screws. Previous operator experience in performing the procedure or technique under general anesthesia is beneficial. Appreciation of appropriate topographic anatomic landmarks is important, and intraoperative radiographic control is useful. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Habitat use by forest bats in South Carolina in relation to local, stand, and landscape characteristics

    Science.gov (United States)

    Susan C. Loeb; Joy M. O' Keefe

    2006-01-01

    Knowledge and understanding of bat habitat associations and the responses of bats to forest management are critical for effective bat conservation and management. Few studies have been conducted on bat habitat use in the southeast, despite the high number of endangered and sensitive species in the region. Our objective was to identify important local, stand, and...

  14. ESTIMATION OF STAND HEIGHT AND FOREST VOLUME USING HIGH RESOLUTION STEREO PHOTOGRAPHY AND FOREST TYPE MAP

    Directory of Open Access Journals (Sweden)

    K. M. Kim

    2016-06-01

    Full Text Available Traditional field methods for measuring tree heights are often too costly and time consuming. An alternative remote sensing approach is to measure tree heights from digital stereo photographs which is more practical for forest managers and less expensive than LiDAR or synthetic aperture radar. This work proposes an estimation of stand height and forest volume(m3/ha using normalized digital surface model (nDSM from high resolution stereo photography (25cm resolution and forest type map. The study area was located in Mt. Maehwa model forest in Hong Chun-Gun, South Korea. The forest type map has four attributes such as major species, age class, DBH class and crown density class by stand. Overlapping aerial photos were taken in September 2013 and digital surface model (DSM was created by photogrammetric methods(aerial triangulation, digital image matching. Then, digital terrain model (DTM was created by filtering DSM and subtracted DTM from DSM pixel by pixel, resulting in nDSM which represents object heights (buildings, trees, etc.. Two independent variables from nDSM were used to estimate forest stand volume: crown density (% and stand height (m. First, crown density was calculated using canopy segmentation method considering live crown ratio. Next, stand height was produced by averaging individual tree heights in a stand using Esri’s ArcGIS and the USDA Forest Service’s FUSION software. Finally, stand volume was estimated and mapped using aerial photo stand volume equations by species which have two independent variables, crown density and stand height. South Korea has a historical imagery archive which can show forest change in 40 years of successful forest rehabilitation. For a future study, forest volume change map (1970s–present will be produced using this stand volume estimation method and a historical imagery archive.

  15. Manager's handbook for jack pine in the north central states.

    Science.gov (United States)

    John W. Benzie

    1977-01-01

    Provides a key for the resource manager to use in choosing silvicultural practices for the management of jack pine. Control of stand composition, growth, and stand establishment for timber production, water, wildlife, and recreation are discussed.

  16. Characterization of structure and development of models to quantify wood potential of an unmanaged Araucaria angustifolia stand

    Directory of Open Access Journals (Sweden)

    Rafaella De Angeli Curto

    2014-12-01

    Full Text Available The objective of this study was to characterize of an unmanaged stand of Araucaria angustifolia and to development of models to quantify the wood potential, aiming to support the development of forest management plans in stands with similar conditions. The work was developed into a stand established in 1946, in National Forest of Açungui, in Campo Largo County, Paraná State, Brazil. There was only one thinning in the stand, between 1970 and 1980. From the frequency of individuals in each diametric class, it was observed the condition of stagnation and competition with cohort in the beginning of class distribution. With the application of the probability density function of Weibull-3P, Trorey model, and the 5th polynomial by diameter class, it was possible to confirm the stock estimative of timber volume of the stand. This analysis indicated that the stand presents average annual wood production smaller than the species potential. So it is recommended the thinning to promote growth of remnant trees. With the probability density function of Weibull-3p, that was selected, it is possible to project the diametric distribution of the stand, when analyzed complementarily with growth diameter information, if the stand remains unmanaged. Certainly, the optimum potential of timber production could have been manifested if the stand were managed during the cycle planed.

  17. Basic Stand Alone Medicare Inpatient Claims PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Inpatient Public Use Files (PUF) named CMS 2008 BSA Inpatient Claims PUF with information from 2008 Medicare...

  18. Compressor Load Stand: Commissioning and Control Strategies

    National Research Council Canada - National Science Library

    Causey, Andrew

    1998-01-01

    .... The purpose of this research project was to commission this load stand, which includes setting up the hardware, setting up a control system, a data acquisition system, and an automatic test sequence system...

  19. Minnesota DNR Forest Stand Inventory Version 2

    Data.gov (United States)

    Minnesota Department of Natural Resources — This layer is a digital inventory of individual forest stands. The data is collected by DNR Foresters in each DNR Forestry Administrative Area, and is updated on a...

  20. Basic Stand Alone Carrier Line Items PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Carrier Line Items Public Use Files (PUF) with information from Medicare Carrier claims. The CMS BSA Carrier Line...

  1. Seismic design method of free standing rack

    International Nuclear Information System (INIS)

    Taniguchi, Katsuhiko; Okuno, Daisaku; Iwasaki, Akihisa; Nekomoto, Yoshitsugu; Matsuoka, Toshihiro

    2013-01-01

    For high earthquake resistance and ease of installation, free standing racks which are not anchored to the pool floor or walls has been adopted in many countries. Under the earthquake, the response of the free standing rack is highly nonlinear and involves a complex combination of motions (sliding, rocking, twisting, and turning) and impacts between the fuel assemblies and the fuel cell walls, rack-to-rack, and the pit floor and rack pedestals. We carried out seismic experiments on the full-scale rack model in water and dry conditions to obtain the fundamental data about free standing rack (sliding, rocking and turning motions). We have developed the nonlinear dynamic analysis method to predict seismic response for the free standing rack utilizing the full-scale test result and verified the analysis evaluation method of the rack by comparison of test result. (author)

  2. Lisa's Lemonade Stand: Exploring Algebraic Ideas.

    Science.gov (United States)

    Billings, Esther M. H.; Lakatos, Tracy

    2003-01-01

    Presents an activity, "Lisa's Lemonade Stand," that actively engages students in algebraic thinking as they analyze change by investigating relationships between variables and gain experience describing and representing these relationships graphically. (YDS)

  3. Three-dimensional instability of standing waves

    Science.gov (United States)

    Zhu, Qiang; Liu, Yuming; Yue, Dick K. P.

    2003-12-01

    We investigate the three-dimensional instability of finite-amplitude standing surface waves under the influence of gravity. The analysis employs the transition matrix (TM) approach and uses a new high-order spectral element (HOSE) method for computation of the nonlinear wave dynamics. HOSE is an extension of the original high-order spectral method (HOS) wherein nonlinear wave wave and wave body interactions are retained up to high order in wave steepness. Instead of global basis functions in HOS, however, HOSE employs spectral elements to allow for complex free-surface geometries and surface-piercing bodies. Exponential convergence of HOS with respect to the total number of spectral modes (for a fixed number of elements) and interaction order is retained in HOSE. In this study, we use TM-HOSE to obtain the stability of general three-dimensional perturbations (on a two-dimensional surface) on two classes of standing waves: plane standing waves in a rectangular tank; and radial/azimuthal standing waves in a circular basin. For plane standing waves, we confirm the known result of two-dimensional side-bandlike instability. In addition, we find a novel three-dimensional instability for base flow of any amplitude. The dominant component of the unstable disturbance is an oblique (standing) wave oriented at an arbitrary angle whose frequency is close to the (nonlinear) frequency of the original standing wave. This finding is confirmed by direct long-time simulations using HOSE which show that the nonlinear evolution leads to classical Fermi Pasta Ulam recurrence. For the circular basin, we find that, beyond a threshold wave steepness, a standing wave (of nonlinear frequency Omega) is unstable to three-dimensional perturbations. The unstable perturbation contains two dominant (standing-wave) components, the sum of whose frequencies is close to 2Omega. From the cases we consider, the critical wave steepness is found to generally decrease/increase with increasing radial

  4. Logging in hardwood stands established on farm land

    International Nuclear Information System (INIS)

    Bjoerheden, R.

    1992-01-01

    Performance and costs for different harvesting systems in broad leaf stands established on former tillage is presented. The calculations, combined with a forecast of the market development, shows that it is risky to aim production exclusively at bulk products as fibre or fibre/energy. The harvest of fibre or energy wood can, however, be used as a means to increase profitability of a silvicultural programme aimed at production of high quality hardwood lumber. Management and logging in these stands will be carried out with small scale technology, often by the private forest owner. Todays large scale systems are not competitive in these stands. The cost calculations show that we lack economically sound systems for harvesting stands in the interval up to 5 cm DBH. The lowest logging cost for these stands was calculated for motor manual felling and chipping with a chipper/dumper mounted on a farm tractor. This alternative is competitive also in the interval 5-10 cm DBH but there is a number of other feasible systems, e.g. off-road chippers processing motor manually felled and piled trees. Tree section systems with extraction by forwarder or a farm tractor with grapple loader and a bogic trailer operates at low costs to roadside but costs for processing and, maybe, a more expensive secondary transportation must then be added. For thinnings in the interval 10-25 cm DBH tree chipping is the most cost efficient if only energy assortments is to be harvested. However, at the current price relations between energy wood and pulpwood tree section systems are preferable also in stands over 10 cm since it allows a combined harvest of fibre and energy. For the same reason, the seemingly most interesting system in later thinnings is a system with differentiated processing. The term denotes a system where pulpwood is cut motor manually down to 12.5 cm and extracted by forwarder or farm tractor. The remaining tops and branches are processed by an off-road chipper. (36 refs., 11 figs.)

  5. Development of prolonged standing strain index to quantify risk levels of standing jobs.

    Science.gov (United States)

    Halim, Isa; Omar, Abdul Rahman

    2012-01-01

    Many occupations in industry such as metal stamping workers, electronics parts assembly operators, automotive industry welders, and lathe operators require working in a standing posture for a long time. Prolonged standing can contribute to discomfort and muscle fatigue particularly in the back and legs. This study developed the prolonged standing strain index (PSSI) to quantify the risk levels caused by standing jobs, and proposed recommendations to minimize the risk levels. Risk factors associated with standing jobs, such as working posture, muscles activity, standing duration, holding time, whole-body vibration, and indoor air quality, were the basis for developing the PSSI. All risk factors were assigned multipliers, and the PSSI was the product of those multipliers. Recommendations for improvement are based on the PSSI; however, extensive studies are required to validate their effectiveness. multipliers, and the PSSI was the product of those multipliers. Recommendations for improvement are based on the PSSI; however, extensive studies are required to validate their effectiveness.

  6. Predicted stand volume for Eucalyptus plantations by spatial analysis

    Science.gov (United States)

    Latifah, Siti; Teodoro, RV; Myrna, GC; Nathaniel, CB; Leonardo, M. F.

    2018-03-01

    The main objective of the present study was to assess nonlinear models generated by integrating the stand volume growth rate to estimate the growth and yield of Eucalyptus. The primary data was done for point of interest (POI) of permanent sample plots (PSPs) and inventory sample plots, in Aek Nauli sector, Simalungun regency,North Sumatera Province,Indonesia. from December 2008- March 2009. Today,the demand for forestry information has continued to grow over recent years. Because many forest managers and decision makers face complex decisions, reliable information has become the necessity. In the assessment of natural resources including plantation forests have been widely used geospatial technology.The yield of Eucalyptus plantations represented by merchantable volume as dependent variable while factors affecting yield namely stands variables and the geographic variables as independent variables. The majority of the areas in the study site has stand volume class 0 - 50 m3/ha with 16.59 ha or 65.85 % of the total study site.

  7. A systematic review of standing and treadmill desks in the workplace.

    Science.gov (United States)

    MacEwen, Brittany T; MacDonald, Dany J; Burr, Jamie F

    2015-01-01

    Standing and treadmill desks are intended to reduce the amount of time spent sitting in today's otherwise sedentary office. Proponents of these desks suggest that health benefits may be acquired as standing desk use discourages long periods of sitting, which has been identified as an independent health risk factor. Our objectives were thus to analyze the evidence for standing and treadmill desk use in relation to physiological (chronic disease prevention and management) and psychological (worker productivity, well-being) outcomes. A computer-assisted systematic search of Medline, PubMed, PsycINFO, SPORTDiscus, CINAHL, CENTRAL, and EMBASE databases was employed to identify all relevant articles related to standing and treadmill desk use. Treadmill desks led to the greatest improvement in physiological outcomes including postprandial glucose, HDL cholesterol, and anthropometrics, while standing desk use was associated with few physiological changes. Standing and treadmill desks both showed mixed results for improving psychological well-being with little impact on work performance. Standing and treadmill desks show some utility for breaking up sitting time and potentially improving select components of health. At present; however, there exist substantial evidence gaps to comprehensively evaluate the utility of each type of desk to enhance health benefits by reducing sedentary time. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Changes to oak woodland stand structure and ground flora composition caused by thinning and burning

    Science.gov (United States)

    Kinkead, Carter O.; Kabrick, John M.; Stambaugh, Michael C.; Grabner, Keith W.

    2013-01-01

    Our objective was to quantify the cumulative effects of prescribed burning and thinning on forest stocking and species composition at a woodland restoration experiment site in the Ozark Highlands of Missouri. Our study used four treatments (burn, harvest, harvest and burn, control) on three slope position and aspect combinations (south, north, ridge) replicated in three complete blocks. Harvested stands were thinned from below to 40 percent residual stocking. Two prescribed fires were applied to both burn and harvest-burn treatment units in a 5-year period. Results reflect changes that have taken place over a 6-year period, from pretreatment conditions to 1 year after the last fire. In this period, there was a 10-percent reduction in the stocking in burned stands compared to control and a 6-percent reduction in harvested and burned stands compared to harvested stands. Compared to the control, percentage ground cover of woodland indicators was seven times greater in burned stands, six times greater in harvested stands, and 22 percent greater in harvested and burned stands. Th ere was no significant (P > 0.05) interaction between aspect and treatment on stocking or ground flora cover. Th is study indicated that silvicultural treatments do achieve various goals that are common to managers who aim to restore woodland communities.

  9. Climate-induced mortality of spruce stands in Belarus

    Science.gov (United States)

    Kharuk, Viacheslav I.; Im, Sergei T.; Dvinskaya, Maria L.; Golukov, Alexei S.; Ranson, Kenneth J.

    2015-12-01

    The aim of this work is an analysis of the causes of spruce (Picea abies L.) decline and mortality in Belarus. The analysis was based on forest inventory and Landsat satellite (land cover classification, climate variables (air temperature, precipitation, evaporation, vapor pressure deficit, SPEI drought index)), and GRACE-derived soil moisture estimation (equivalent of water thickness anomalies, EWTA). We found a difference in spatial patterns between dead stands and all stands (i.e., before mortality). Dead stands were located preferentially on relief features with higher water stress risk (i.e., higher elevations, steeper slopes, south and southwestern exposure). Spruce mortality followed a series of repeated droughts between 1990 and 2010. Mortality was negatively correlated with air humidity (r = -0.52), and precipitation (r = -0.57), and positively correlated with the prior year vapor pressure deficit (r = 0.47), and drought increase (r = 0.57). Mortality increased with the increase in occurrence of spring frosts (r = 0.5), and decreased with an increase in winter cloud cover (r = -0.37). Spruce mortality was negatively correlated with snow water accumulation (r = -0.81) and previous year anomalies in water soil content (r = -0.8). Weakened by water stress, spruce stands were attacked by pests and phytopathogens. Overall, spruce mortality in Belarussian forests was caused by drought episodes and drought increase in synergy with pest and phytopathogen attacks. Vast Picea abies mortality in Belarus and adjacent areas of Russia and Eastern Europe is a result of low adaptation of that species to increased drought. This indicates the necessity of spruce replacement by drought-tolerant indigenous (e.g., Pinus sylvestris, Querqus robur) or introduced (e.g., Larix sp. or Pseudotsuga menzieslii) species to obtain sustainable forest growth management.

  10. Stand for visual ultrasonic testing of spent fuel

    International Nuclear Information System (INIS)

    Czajkowski, W.; Borek-Kruszewska, E.

    2001-01-01

    A stand for visual and ultrasonic testing of spent fuel, constructed under Strategic Governmental Programme for management of spent fuel and radioactive waste, is presented in the paper. The stand, named 'STEND-1', built up at the Institute of Atomic Energy in Swjerk, is appointed for underwater visual testing of spent fuel elements type MR6 and WWR by means of TV-CCD camera and image processing system and for ultrasonic scanning of external surface of these elements by means of video scan immersion transducer and straight UHT connector. 'STEND-1' is built using flexible in use, high-tensile, anodized aluminum profiles. All the profiles feature longitudinal grooves to accommodate connecting elements and for the attachment of accessories at any position. They are also characterised by straight-through core bores for use with standard fastening elements and to accommodate accessory components. Stand, equipped with automatic control and processing system based on personal computer, may be manually or automatically controlled. Control system of movements of the camera in the vertical axis and rotational movement of spent fuel element permits to fix chosen location of fuel element with accuracy better than 0.1 mm. High resolution of ultrasonic method allows to record damages of outer surface of order 0.1 mm. The results of visual testing of spent fuel are recorded on video tape and then may be stored on the hard disc of the personal computer and presented in shape of photo or picture. Only selected damage surfaces of spent fuel elements are tested by means of ultrasonic scanning. All possibilities of the stand and results of visual testing of spent fuel type WWR are presented in the paper. (author)

  11. Estimating Stand Volume and Above-Ground Biomass of Urban Forests Using LiDAR

    Directory of Open Access Journals (Sweden)

    Vincenzo Giannico

    2016-04-01

    Full Text Available Assessing forest stand conditions in urban and peri-urban areas is essential to support ecosystem service planning and management, as most of the ecosystem services provided are a consequence of forest stand characteristics. However, collecting data for assessing forest stand conditions is time consuming and labor intensive. A plausible approach for addressing this issue is to establish a relationship between in situ measurements of stand characteristics and data from airborne laser scanning (LiDAR. In this study we assessed forest stand volume and above-ground biomass (AGB in a broadleaved urban forest, using a combination of LiDAR-derived metrics, which takes the form of a forest allometric model. We tested various methods for extracting proxies of basal area (BA and mean stand height (H from the LiDAR point-cloud distribution and evaluated the performance of different models in estimating forest stand volume and AGB. The best predictors for both models were the scale parameters of the Weibull distribution of all returns (except the first (proxy of BA and the 95th percentile of the distribution of all first returns (proxy of H. The R2 were 0.81 (p < 0.01 for the stand volume model and 0.77 (p < 0.01 for the AGB model with a RMSE of 23.66 m3·ha−1 (23.3% and 19.59 Mg·ha−1 (23.9%, respectively. We found that a combination of two LiDAR-derived variables (i.e., proxy of BA and proxy of H, which take the form of a forest allometric model, can be used to estimate stand volume and above-ground biomass in broadleaved urban forest areas. Our results can be compared to other studies conducted using LiDAR in broadleaved forests with similar methods.

  12. Remote sensing estimates of stand-replacement fires in Russia, 2002–2011

    International Nuclear Information System (INIS)

    Krylov, Alexander; Potapov, Peter; Loboda, Tatiana; Tyukavina, Alexandra; Turubanova, Svetlana; Hansen, Matthew C; McCarty, Jessica L

    2014-01-01

    The presented study quantifies the proportion of stand-replacement fires in Russian forests through the integrated analysis of Landsat and Moderate Resolution Imaging Spectroradiometer (MODIS) data products. We employed 30 m Landsat Enhanced Thematic Mapper Plus derived tree canopy cover and decadal (2001–2012) forest cover loss (Hansen et al 2013 High-resolution global maps of 21st-century forest cover change Science 342 850–53) to identify forest extent and disturbance. These data were overlaid with 1 km MODIS active fire (earthdata.nasa.gov/data/near-real-time-data/firms) and 500 m regional burned area data (Loboda et al 2007 Regionally adaptable dNBR-based algorithm for burned area mapping from MODIS data Remote Sens. Environ. 109 429–42 and Loboda et al 2011 Mapping burned area in Alaska using MODIS data: a data limitations-driven modification to the regional burned area algorithm Int. J. Wildl. Fire 20 487–96) to differentiate stand-replacement disturbances due to fire versus other causes. Total stand replacement forest fire area within the Russian Federation from 2002 to 2011 was estimated to be 17.6 million ha (Mha). The smallest stand-replacement fire loss occurred in 2004 (0.4 Mha) and the largest annual loss in 2003 (3.3 Mha). Of total burned area within forests, 33.6% resulted in stand-replacement. Light conifer stands comprised 65% of all non-stand-replacement and 79% of all stand-replacement fire in Russia. Stand-replacement area for the study period is estimated to be two times higher than the reported logging area. Results of this analysis can be used with historical fire regime estimations to develop effective fire management policy, increase accuracy of carbon calculations, and improve fire behavior and climate change modeling efforts. (paper)

  13. The Influence of Residual Stand Densities on Regeneration in Sugar Maple Stands

    Science.gov (United States)

    Carl H. Tubbs

    1968-01-01

    Studies of regeneration 2, 5, and 10 years after cutting mature and overmature sugar maple stands to several residual densities show that (1) sugar maple is still the predominant species under all stand densities (2) nearly all regeneration reaching larger size classes became established before cutting (3) heavier cuttings (30, 50, and 70 square feet) are more rapidly...

  14. Advance reproduction and other stand characteristics in Pennsylvania and French stands of northern red oak

    Science.gov (United States)

    Kim C. Steiner; Marc D. Abrams; Todd W. Bowersox

    1993-01-01

    The frequent scarcity of northern red oak (NRO) advance reproduction raises questions about its regeneration potential under prevailing stand conditions in eastern North America. In contrast, NRO plantations in France typically contain abundant advance reproduction. The purpose of this study was to document stand conditions in Pennsylvania (PA) and southwestern France...

  15. Phenology and abundance of Enoicyla pusilla in conifer stands

    Directory of Open Access Journals (Sweden)

    M. J. Lombardero

    2013-07-01

    Full Text Available Aim of Study. We study the abundance of Enoicyla pusilla (Burmeister in pine plantations and the effects of silvicultural thinning on insect population. This species is considered a rare member of the order Trichoptera, reported as absent or occasional in conifer forests. It has been suggested that the proliferation of conifer plantations may be a threat for this species by favoring population isolation. Area of study. Plantations of native and non-native pines in Galicia (NW of Spain.Material and Methods. We used different traps systems, including 28 pitfall traps, to compared populations of insects in 14 thinned and unthinned plots of Pinus pinaster and P. radiata distributed across 3 forest stands. Traps were checked every 15 days during one year.Main results.  We caught 1.219 larvae of E. pusilla. It was the third most abundant species captured in pitfall traps. Larval activity extended from January to late July. They were more abundant in the stands of P. radiata, probably because the denser foliage produced limits sunlight and helped to maintain litter moisture. Additionally needles of P. radiata had lower toughness and higher nitrogen content, which probably makes it a higher quality resource for the detritivorous larvae. Thinning did not affect larvae population.Research highlights: Although managed forests cannot match the biodiversity value of native mixed species stands, if managed appropriately, they may provide habitat for native fauna while also allowing for forest productionKey words: caddisfly; Pinus pinaster; Pinus radiate; plantations; thinning.

  16. High-voltage test stand at Livermore

    International Nuclear Information System (INIS)

    Smith, M.E.

    1977-01-01

    This paper describes the present design and future capability of the high-voltage test stand for neutral-beam sources at Lawrence Livermore Laboratory. The stand's immediate use will be for testing the full-scale sources (120 kV, 65 A) for the Tokamak Fusion Test Reactor. It will then be used to test parts of the sustaining source system (80 kV, 85 A) being designed for the Magnetic Fusion Test Facility. Following that will be an intensive effort to develop beams of up to 200 kV at 20 A by accelerating negative ions. The design of the test stand features a 5-MVA power supply feeding a vacuum tetrode that is used as a switch and regulator. The 500-kW arc supply and the 100-kW filament supply for the neutral-beam source are battery powered, thus eliminating one or two costly isolation transformers

  17. Stand development of trembling aspen in Canaan Valley, West Virginia

    Science.gov (United States)

    James S. Rentch; James T. Anderson

    2008-01-01

    In wetlands of Canaan Valley, West Virginia, trembling aspen occurs as a disjunct population well south of its primary natural range. Based on sample data from 15 stands, we found that aspen occurs as nearly monospecific stands or clones. Eight stands had median ages between 30 and 40 yrs, and we suggest that stand initiation was related to changes in land use after...

  18. Future directions in standing-wave photoemission

    Energy Technology Data Exchange (ETDEWEB)

    Gray, Alexander X., E-mail: axgray@temple.edu

    2014-08-15

    Highlights: • Probing magnetic properties at the buried interface with SW-MCD. • Probing electronic structure at the buried interface with resonant SW-XPS and SW-HAXPES. • Probing momentum-resolved electronic structure at a buried interface with SWARPES. • Adding depth resolution to photoemission microscopy with standing-wave excitation. • Standing-wave localization, total reflection and waveguide effects. - Abstract: Over the past decade, standing-wave photoemission (SW-XPS) has evolved into a powerful and versatile non-destructive technique for probing element-specific electronic, magnetic, and structural properties of buried layers and interfaces with sub-nanometer depth resolution. In this article, I will discuss several promising future directions in this emergent field stemming from experimental and theoretical studies wherein SW-XPS is combined with other X-ray techniques, such as magnetic circular dichroism (MCD), hard X-ray photoemission spectroscopy (HAXPES), angle-resolved photoemission (ARPES), and photoemission microscopy (PEEM), adding extra dimensions to the measurement and thus widening the scope of scientific and technological questions accessible via the use of standing waves. I will further discuss examples of recently developed methods for X-ray standing-wave data analysis, which yield layer-resolved matrix-element-weighted densities of states at interfaces as well as Ångstrom-level changes in periodicity of synthetic superlattices. Finally, I will explore the possibility of localizing the standing waves near the surface and within a buried layer by the use of aperiodic superlattices, total reflection, and X-ray waveguide effects.

  19. Future directions in standing-wave photoemission

    International Nuclear Information System (INIS)

    Gray, Alexander X.

    2014-01-01

    Highlights: • Probing magnetic properties at the buried interface with SW-MCD. • Probing electronic structure at the buried interface with resonant SW-XPS and SW-HAXPES. • Probing momentum-resolved electronic structure at a buried interface with SWARPES. • Adding depth resolution to photoemission microscopy with standing-wave excitation. • Standing-wave localization, total reflection and waveguide effects. - Abstract: Over the past decade, standing-wave photoemission (SW-XPS) has evolved into a powerful and versatile non-destructive technique for probing element-specific electronic, magnetic, and structural properties of buried layers and interfaces with sub-nanometer depth resolution. In this article, I will discuss several promising future directions in this emergent field stemming from experimental and theoretical studies wherein SW-XPS is combined with other X-ray techniques, such as magnetic circular dichroism (MCD), hard X-ray photoemission spectroscopy (HAXPES), angle-resolved photoemission (ARPES), and photoemission microscopy (PEEM), adding extra dimensions to the measurement and thus widening the scope of scientific and technological questions accessible via the use of standing waves. I will further discuss examples of recently developed methods for X-ray standing-wave data analysis, which yield layer-resolved matrix-element-weighted densities of states at interfaces as well as Ångstrom-level changes in periodicity of synthetic superlattices. Finally, I will explore the possibility of localizing the standing waves near the surface and within a buried layer by the use of aperiodic superlattices, total reflection, and X-ray waveguide effects

  20. Free-Standing, Flexible, Superomniphobic Films.

    Science.gov (United States)

    Vahabi, Hamed; Wang, Wei; Movafaghi, Sanli; Kota, Arun K

    2016-08-31

    Fabrication of most superomniphobic surfaces requires complex process conditions or specialized and expensive equipment or skilled personnel. In order to circumvent these issues and make them end-user-friendly, we developed the free-standing, flexible, superomniphobic films. These films can be stored and delivered to the end-users, who can readily attach them to virtually any surface (even irregular shapes) and impart superomniphobicity. The hierarchical structure, the re-entrant texture, and the low solid surface energy render our films superomniphobic for a wide variety of liquids. We demonstrate that our free-standing, flexible, superomniphobic films have applications in enhanced chemical resistance and enhanced weight bearing.

  1. [Occupational standing vibration rate and vibrational diseases].

    Science.gov (United States)

    Karnaukh, N G; Vyshchipan, V F; Haumenko, B S

    2003-12-01

    Occupational standing vibration rate is proposed in evaluating a degree of impairment of an organism activity. It will allow more widely to introduce specification of quality and quantity in assessment of the development of vibrational disease. According out-patient and inpatient obtained data we have established criterial values of functional changes in accordance with accumulated occupational standing vibration rate. The nomogram was worked out for defining a risk of the development of vibrational disease in mine workers. This nomogram more objectively can help in diagnostics of the disease.

  2. Stand alone photovoltaic systems: guarantee of results

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This study aims to provide a guarantee of results for system performance for users of stand-alone photovoltaic (PV) systems, which have no back-up generator. The appropriate main performance criterion for PV systems is that a specified load is supplied with power either continuously or intermittently whenever the load requires power. A methodology to evaluate the power availability of stand-alone PV systems has been developed as part of the project, which encompasses power losses due to weather variations. The guarantee of results produced allows users to compare system designs from different manufacturers. (UK)

  3. Introducing sit-stand desks increases classroom standing time among university students.

    Science.gov (United States)

    Jerome, Matthew; Janz, Kathleen F; Baquero, Barbara; Carr, Lucas J

    2017-12-01

    Excessive sedentary behavior has been associated with many negative health outcomes. While an understudied health topic, there is evidence that university students are excessively sedentary. Sit-stand desks have been shown to reduce sedentary time among pre-university students (ages 5-18 years) and sedentary workers but have not been tested in university classrooms. This study tested the effects of introducing sit-stand desks into a university classroom on student's classroom sitting and standing behaviors. Using a cross-over design, students received access to both traditional seated desks and sit-stand desks for six weeks. Data were collected between September and December, 2016. We recruited 304 healthy undergraduate university students enrolled in one of two small (25 seats) classrooms at a large Midwestern university during the fall of 2016. Average minutes of standing/hour/student, average percent class time spent standing, and the number of sit-stand transitions/student/hour were directly observed with video camera surveillance. Participants stood significantly more (p classrooms as an approach to reduce sedentary behaviors of university students.

  4. Learning to Stand: The Acceptability and Feasibility of Introducing Standing Desks into College Classrooms

    Directory of Open Access Journals (Sweden)

    Roberto M. Benzo

    2016-08-01

    Full Text Available Prolonged sedentary behavior is an independent risk factor for multiple negative health outcomes. Evidence supports introducing standing desks into K-12 classrooms and work settings to reduce sitting time, but no studies have been conducted in the college classroom environment. The present study explored the acceptability and feasibility of introducing standing desks in college classrooms. A total of 993 students and 149 instructors completed a single online needs assessment survey. This cross-sectional study was conducted during the fall semester of 2015 at a large Midwestern University. The large majority of students (95% reported they would prefer the option to stand in class. Most students (82.7% reported they currently sit during their entire class time. Most students (76.6% and instructors (86.6% reported being in favor of introducing standing desks into college classrooms. More than half of students and instructors predicted having access to standing desks in class would improve student’s “physical health”, “attention”, and “restlessness”. Collectively, these findings support the acceptability of introducing standing desks in college classrooms. Future research is needed to test the feasibility, cost-effectiveness and efficacy of introducing standing desks in college classrooms. Such studies would be useful for informing institutional policies regarding classroom designs.

  5. Long standing intra oral acid burn

    NARCIS (Netherlands)

    Kumar, V.V.; Ebenezer, S.; Lobbezoo, F.

    2015-01-01

    Oral burn due to ingestion of corrosive substances can bring about debilitating consequences. It often brings mortality, and the survivors can have severe impairment of functions, especially in relation to the stomatognathic and gastrointestinal systems. This article presents a long-standing case

  6. Estimating white trunk rot in aspen stands

    Science.gov (United States)

    Alan C. Jones; Michael E. Ostry

    1998-01-01

    Advanced decay caused by Phellinus tremulae was estimated in 295 trembling aspen on 30 plots in 2 Minnesota counties using existing inventory guides, and then measured by felling and sectioning the trees. In standing trees, decay volume was underestimated by 38% compared to measured decay volume in felled trees. The most reliable external indicator...

  7. Large optics inspection, tilting, and washing stand

    Science.gov (United States)

    Ayers, Marion Jay [Brentwood, CA; Ayers, Shannon Lee [Brentwood, CA

    2010-08-24

    A large optics stand provides a risk free means of safely tilting large optics with ease and a method of safely tilting large optics with ease. The optics are supported in the horizontal position by pads. In the vertical plane the optics are supported by saddles that evenly distribute the optics weight over a large area.

  8. Direct sampling for stand density index

    Science.gov (United States)

    Mark J. Ducey; Harry T. Valentine

    2008-01-01

    A direct method of estimating stand density index in the field, without complex calculations, would be useful in a variety of silvicultural situations. We present just such a method. The approach uses an ordinary prism or other angle gauge, but it involves deliberately "pushing the point" or, in some cases, "pulling the point." This adjusts the...

  9. IMS Learning Design: De stand van zaken

    NARCIS (Netherlands)

    Tattersall, Colin; Manderveld, Jocelyn

    2005-01-01

    Tattersall, C. & Manderveld, J. (2004) IMS Learning Design: De stand van zaken In: Gorissen, P., Manderveld, J., Benneker, F. & Cordewener, B. Leertechnologie in de Lage Landen (pp. 31-33). Utrecht, Stichting Surf. Ook beschikbaar in dspace: http://hdl.handle.net/1820/270

  10. AA, wide quadrupole on measurement stand

    CERN Multimedia

    CERN PhotoLab

    1981-01-01

    Please look up 8101024 and 8103203 first. Wide quadrupole (QFW, QDW) with end-shims and shimming washers on the measurement stand. With the measurement coil one measured the harmonics of the magnetic field, determined the magnetic centre, and catalogued the effect of washer constellations.

  11. Standing waves in fiber-optic interferometers

    NARCIS (Netherlands)

    De Haan, V.; Santbergen, R.; Tijssen, M.; Zeman, M.

    2011-01-01

    A study is presented giving the response of three types of fiber-optic interferometers by which a standing wave through an object is investigated. The three types are a Sagnac, Mach–Zehnder and Michelson–Morley interferometer. The response of the Mach–Zehnder interferometer is similar to the Sagnac

  12. Standing stability evaluation using a triaxial accelerometer

    NARCIS (Netherlands)

    Mayagoitia, Ruth E.; Mayagoitia, R.E.; Lötters, Joost Conrad; Lotters, Joost Conrad; Veltink, Petrus H.

    1996-01-01

    A triaxial accelerometer is placed at the back of the subject at the height of the center of mass. Force plate data are collected simultaneously. Subjects stand in a comfortable position with eyes open, eyes closed and doing cognitive tasks; and with feet together with eyes open and closed. The

  13. Standing on the shoulders of giants.

    Science.gov (United States)

    Romanovsky, Andrej A

    2014-01-01

    In this editorial, the author explains that the journal Temperature stands on the shoulders of giants-prominent scientists of the past and current members of the Temperature community. Temperature also uses the best tools, such as Google Scholar profiles. The editorial includes a new puzzle: why does warm water freeze faster than cold water?

  14. Bureau of Land Management density management study.

    Science.gov (United States)

    John Cissel; Paul Anderson; Shanti Berryman; Sam Chan; Deanna Olson; Klaus. Puettman

    2004-01-01

    The Bureau of Land Management (BLM), Pacific Northwest Research Station (PNW), U.S. Geological Survey (USGS), and Oregon State University (OSU) established the Density Management Study (DMS) in 1994 to develop and test options for young stand management to meet Northwest Forest Plan objectives in western Oregon. The DMS demonstrates and evaluates alternative approaches...

  15. The ambiguity of standing in standing devices: a qualitative interview study concerning children and parents experiences of the use of standing devices.

    Science.gov (United States)

    Nordström, Birgitta; Näslund, Annika; Ekenberg, Lilly; Zingmark, Karin

    2014-10-01

    The aim of this study was to describe children's and parents' experiences of the significance of standing in a standing device. Individual interviews were performed with six children/teenagers (aged 7-19 years) and 14 parents. The interviews were transcribed and analyzed using a qualitative content analysis. The analysis resulted in the major theme, the duality of uprightness and the related themes: (1) the instrumental dimension of standing; (2) the social dimension of standing; and (3) the ambivalent dimension of standing. Each of the themes comprised several subthemes. There is an inherent duality related to the use of a standing device. Standing in a standing device was seen as a treatment of body structures and functions, as well as a possible source of pain. Standing was considered to influence freedom in activities and participation both positively and negatively. The parents experienced that standing influenced other peoples' views of their child, while the children experienced standing as a way to extend the body and as something that gave them benefits in some activities. Physiotherapists working with children should take into account both the social and physical dimensions of using a standing device and consider both the child's and the parents' views.

  16. Conjunction of standing wave and resonance in asymmetric nanowires: a mechanism for thermal rectification and remote energy accumulation.

    Science.gov (United States)

    Liu, Yue-Yang; Zhou, Wu-Xing; Chen, Ke-Qiu

    2015-12-02

    As an important way to control and manage heat transport, thermal rectification has become an elementary issue in the field of phononics and plays a key role in the designing of thermal devices. Here we investigate systematically the standing wave and the accompanying resonance process in asymmetric nanowires to understand the standing wave itself and its great effect on thermal rectification. Results show that the standing wave is sensitive to both the structural and thermal properties of the material, and its great effect on enhancing the thermal rectification is realized not only by the energy-localization nature of the standing wave, but also by the resonance-caused large amplitude and high energy of the standing wave.

  17. Spatial and thematic assessment of object-based forest stand delineation using an OFA-matrix

    Science.gov (United States)

    Hernando, A.; Tiede, D.; Albrecht, F.; Lang, S.

    2012-10-01

    The delineation and classification of forest stands is a crucial aspect of forest management. Object-based image analysis (OBIA) can be used to produce detailed maps of forest stands from either orthophotos or very high resolution satellite imagery. However, measures are then required for evaluating and quantifying both the spatial and thematic accuracy of the OBIA output. In this paper we present an approach for delineating forest stands and a new Object Fate Analysis (OFA) matrix for accuracy assessment. A two-level object-based orthophoto analysis was first carried out to delineate stands on the Dehesa Boyal public land in central Spain (Avila Province). Two structural features were first created for use in class modelling, enabling good differentiation between stands: a relational tree cover cluster feature, and an arithmetic ratio shadow/tree feature. We then extended the OFA comparison approach with an OFA-matrix to enable concurrent validation of thematic and spatial accuracies. Its diagonal shows the proportion of spatial and thematic coincidence between a reference data and the corresponding classification. New parameters for Spatial Thematic Loyalty (STL), Spatial Thematic Loyalty Overall (STLOVERALL) and Maximal Interfering Object (MIO) are introduced to summarise the OFA-matrix accuracy assessment. A stands map generated by OBIA (classification data) was compared with a map of the same area produced from photo interpretation and field data (reference data). In our example the OFA-matrix results indicate good spatial and thematic accuracies (>65%) for all stand classes except for the shrub stands (31.8%), and a good STLOVERALL (69.8%). The OFA-matrix has therefore been shown to be a valid tool for OBIA accuracy assessment.

  18. Relating demographic characteristics of a small mammal to remotely sensed forest-stand condition.

    Directory of Open Access Journals (Sweden)

    Hania Lada

    Full Text Available Many ecological systems around the world are changing rapidly in response to direct (land-use change and indirect (climate change human actions. We need tools to assess dynamically, and over appropriate management scales, condition of ecosystems and their responses to potential mitigation of pressures. Using a validated model, we determined whether stand condition of floodplain forests is related to densities of a small mammal (a carnivorous marsupial, Antechinus flavipes in 60,000 ha of extant river red gum (Eucalyptus camaldulensis forests in south-eastern Australia in 2004, 2005 and 2011. Stand condition was assessed remotely using models built from ground assessments of stand condition and satellite-derived reflectance. Other covariates, such as volumes of fallen timber, distances to floods, rainfall and life stages were included in the model. Trapping of animals was conducted at 272 plots (0.25 ha across the region. Densities of second-year females (i.e. females that had survived to a second breeding year and of second-year females with suckled teats (i.e. inferred to have been successful mothers were higher in stands with the highest condition. There was no evidence of a relationship with stand condition for males or all females. These outcomes show that remotely-sensed estimates of stand condition (here floodplain forests are relatable to some demographic characteristics of a small mammal species, and may provide useful information about the capacity of ecosystems to support animal populations. Over-regulation of large, lowland rivers has led to declines in many facets of floodplain function. If management of water resources continues as it has in recent decades, then our results suggest that there will be further deterioration in stand condition and a decreased capacity for female yellow-footed antechinuses to breed multiple times.

  19. Harvesting cost model for small trees in natural stands in the interior northwest.

    Science.gov (United States)

    Bruce R. Hartsough; Xiaoshan Zhang; Roger D. Fight

    2001-01-01

    Realistic logging cost models are needed for long-term forest management planning. Data from numerous published studies were combined to estimate the costs of harvesting small trees in natural stands in the Interior Northwest of North America. Six harvesting systems were modeled. Four address gentle terrain: manual log-length, manual whole-tree, mechanized whole-tree,...

  20. Modeling loblolly pine aboveground live biomass in a mature pine-hardwood stand: a cautionary tale

    Science.gov (United States)

    D. C. Bragg

    2011-01-01

    Carbon sequestration in forests is a growing area of interest for researchers and land managers. Calculating the quantity of carbon stored in forest biomass seems to be a straightforward task, but it is highly dependent on the function(s) used to construct the stand. For instance, there are a number of possible equations to predict aboveground live biomass for loblolly...

  1. Height development of shade-tolerant conifer saplings in multiaged Acadian forest stands

    Science.gov (United States)

    Andrew R. Moores; Robert S. Seymour; Laura S. Kenefic

    2007-01-01

    Understory growth dynamics of northern conifer species were studied in four stands managed under multiaged silvicultural systems in eastern Maine. Height growth of Picea rubens Sarg., Abies balsamea (L.) Mill., and Tsuga canadensis (L.) Carr. saplings between 0.5 and 6.0 m in height was related to the proportion...

  2. Cavity-nesting bird abundance in thinned versus unthinned Massachusetts oak stands

    Science.gov (United States)

    Christopher J.E. Welsh; William M. Healy; Richard M. DeGraaf

    1992-01-01

    Cavity-nesting birds provide significant benefits to forest communities, but timber management techniques may negatively affect cavity-nesting species by reducing the availability of suitable nest and foraging sites. We surveyed cavity-nesting birds from transects in eight Massachusetts oak stands to examine the effect of thinning with retention of snag and wildlife...

  3. Grapevine dynamics after manual tending of juvenile stands on the Hoosier National Forest, Indiana

    Science.gov (United States)

    Robert C. Morrissey; Martin-Michel Gauthier; John A., Jr. Kershaw; Douglass F. Jacobs; Burnell C. Fischer; John R. Siefert

    2008-01-01

    Large woody vines, most notably grapevines, are a source of great concern for forest and wildlife managers in many parts of the Central Hardwood Forest Region of the United States. We examined grapevine dynamics in stands aged 21 - 35 years. The plots, located in regenerated clearcuts in the Hoosier National Forest (HNF), were evaluated for vine control, site, and tree...

  4. Assessing wildfire occurrence probability in Pinus pinaster Ait. stands in Portugal

    Energy Technology Data Exchange (ETDEWEB)

    Marques, S.; Garcia-Gonzalo, J.; Botequim, B.; Ricardo, A.; Borges, J. G.; Tome, M.; Oliveira, M. M.

    2012-11-01

    Maritime pine (Pinus pinaster Ait.) is an important conifer from the western Mediterranean Basin extending over 22% of the forest area in Portugal. In the last three decades nearly 4% of Maritime pine area has been burned by wildfires. Yet no wildfire occurrence probability models are available and forest and fire management planning activities are thus carried out mostly independently of each other. This paper presents research to address this gap. Specifically, it presents a model to assess wildfire occurrence probability in regular and pure Maritime pine stands in Portugal. Emphasis was in developing a model based on easily available inventory data so that it might be useful to forest managers. For that purpose, data from the last two Portuguese National Forest Inventories (NFI) and data from wildfire perimeters in the years from 1998 to 2004 and from 2006 to 2007 were used. A binary logistic regression model was build using biometrics data from the NFI. Biometric data included indicators that might be changed by operations prescribed in forest planning. Results showed that the probability of wildfire occurrence in a stand increases in stand located at steeper slopes and with high shrubs load while it decreases with precipitation and with stand basal area. These results are instrumental for assessing the impact of forest management options on wildfire probability thus helping forest managers to reduce the risk of wildfires. (Author) 57 refs.

  5. Factors influencing organic-horizon carbon pools in mixed-species stands of central Maine, USA

    Science.gov (United States)

    Joshua J. Puhlick; Shawn Fraver; Ivan J. Fernandez; Aaron R. Weiskittel; Laura S. Kenefic; Randy Kolka; Marie-Cecile Gruselle

    2016-01-01

    The overall goal of this study was to evaluate the correlation of multiple abiotic and biotic factors with organic-horizon (O-horizon) carbon (C) content on the Penobscot Experimental Forest in central Maine, USA. O-horizon samples were collected and their associated depths were recorded from stands managed with a range of silvicultural and harvesting treatments (i.e...

  6. Estimating long-term carbon sequestration patterns in even- and uneven-aged southern pine stands

    Science.gov (United States)

    Don C. Bragg; James M. Guldin

    2010-01-01

    Carbon (C) sequestration has become an increasingly important consideration for forest management in North America, and has particular potential in pine-dominated forests of the southern United States. Using existing literature on plantations and long-term studies of naturally regenerated loblolly (Pinus taeda) and shortleaf (Pinus echinata) pine-dominated stands on...

  7. Logging damage using an individual tree selection practice in Appalachian hardwood stands

    Science.gov (United States)

    Neil I. Lamson; H. Clay Smith; Gary W. Miller

    1985-01-01

    Four West Virginia hardwood stands, managed using individual-tree selection for the past 30 years, were examined after the third and, in one instance, the fourth periodic harvest to determine the severity of logging damage. On existing skid roads, trees were removed with a rubber-tired skidder or a crawler tractor with a rubber-tired arch. Logging damage reduced...

  8. Iterative development of Stand Up Australia: a multi-component intervention to reduce workplace sitting

    Science.gov (United States)

    2014-01-01

    Background Sitting, particularly in prolonged, unbroken bouts, is widespread within the office workplace, yet few interventions have addressed this newly-identified health risk behaviour. This paper describes the iterative development process and resulting intervention procedures for the Stand Up Australia research program focusing on a multi-component workplace intervention to reduce sitting time. Methods The development of Stand Up Australia followed three phases. 1) Conceptualisation: Stand Up Australia was based on social cognitive theory and social ecological model components. These were operationalised via a taxonomy of intervention strategies and designed to target multiple levels of influence including: organisational structures (e.g. via management consultation), the physical work environment (via provision of height-adjustable workstations), and individual employees (e.g. via face-to-face coaching). 2) Formative research: Intervention components were separately tested for their feasibility and acceptability. 3) Pilot studies: Stand Up Comcare tested the integrated intervention elements in a controlled pilot study examining efficacy, feasibility and acceptability. Stand Up UQ examined the additional value of the organisational- and individual-level components over height-adjustable workstations only in a three-arm controlled trial. In both pilot studies, office workers’ sitting time was measured objectively using activPAL3 devices and the intervention was refined based on qualitative feedback from managers and employees. Results Results and feedback from participants and managers involved in the intervention development phases suggest high efficacy, acceptance, and feasibility of all intervention components. The final version of the Stand Up Australia intervention includes strategies at the organisational (senior management consultation, representatives consultation workshop, team champions, staff information and brainstorming session with information

  9. Standing Classrooms: Research and Lessons Learned from Around the World.

    Science.gov (United States)

    Hinckson, Erica; Salmon, Jo; Benden, Mark; Clemes, Stacey A; Sudholz, Bronwyn; Barber, Sally E; Aminian, Saeideh; Ridgers, Nicola D

    2016-07-01

    Children spend between 50 and 70 % of their time sitting while at school. Independent of physical activity levels, prolonged sitting is associated with poor health outcomes in adulthood. While there is mixed evidence of health associations among children and adolescents, public health guidelines in the USA, UK, Australia and Canada now recommend young people should break up long periods of sitting as frequently as possible. A potentially effective approach for reducing and breaking up sitting throughout the day is changing the classroom environment. This paper presents an overview of a relatively new area of research designed to reduce youth sitting time while at school by changing the classroom environment (n = 13 studies). Environmental changes included placement of height-adjustable or stand-biased standing desks/workstations with stools, chairs, exercise balls, bean bags or mats in the classroom. These 13 published studies suggest that irrespective of the approach, youth sitting time was reduced by between ~44 and 60 min/day and standing time was increased by between 18 and 55 min/day during classroom time at school. Other benefits include increased energy expenditure and the potential for improved management of students' behaviour in the classroom. However, few large trials have been conducted, and there remains little evidence regarding the impact on children's learning and academic achievement. Nevertheless, with an increasing demand placed on schools and teachers regarding students' learning outcomes, strategies that integrate moving throughout the school day and that potentially enhance the learning experience and future health outcomes for young people warrant further exploration.

  10. In Good Standing: "Helping Colleges Manage Student Default Rates"

    Science.gov (United States)

    Boerner, Heather

    2014-01-01

    The U.S. Department of Education estimates that 20 percent of community college students default on their student loan obligations (compared with 14.7 percent of all student loan borrowers), and that number is rising. What can community college financial officers do to keep their default numbers low? In this article, Heather Boerner describes the…

  11. The weed infestation of extensively managed grass stands

    Czech Academy of Sciences Publication Activity Database

    Kocourková, Daniela; Fuksa, R.; Hakl, J.; Hlavičková, D.; Mrkvička, J.

    2008-01-01

    Roč. 2008, Sp.Iss.21 (2008), s. 561-564 ISSN 1861-3829 Institutional research plan: CEZ:AV0Z50380511 Keywords : Bromus inermis * Festuca arundinacea * Festulolium Subject RIV: EF - Botanics Impact factor: 0.566, year: 2008

  12. Transformation of solar radiation in Norway spruce stands into produced biomass - the effect of stand density

    International Nuclear Information System (INIS)

    Marková, I.; Marek, M.V.; Pokorný, R.

    2011-01-01

    The present paper is focused on the assessment of the effects of stand density and leaf area development on radiation use efficiency in the mountain cultivated Norway spruce stand. The young even-aged (17-years-old in 1998) plantation of Norway spruce was divided into two experimental plots differing in their stand density in 1995. During the late spring of 2001 next cultivating high-type of thinning of 15% intensity in a reduction of stocking density was performed. The PAR regime of investigated stands was continually measured since 1992. Total aboveground biomass (TBa) and TBa increment were obtained on the basis of stand inventory. The dynamic of LAI development showed a tendency to be saturated, i.e. the LAI value close to 11 seems to be maximal for the local conditions of the investigated mountain cultivated Norway spruce stand in the Beskids Mts. Remarkable stimuli (up to 17%) of LAI formation were started in 2002, i.e. as an immediate response to thinning. Thus, the positive effect of thinning on LAI increase was confirmed. The data set of absorbed PAR and produced TBa in the period 1998-2003 was processed by the linear regression of Monteith's model, which provided the values of the coefficient of solar energy conversion efficiency into biomass formation. The differences in biomass formation values between the dense and sparse plot after thinning amounted to 18%

  13. Optimal uneven-aged stocking guides: an application to spruce-fir stands in New England

    Science.gov (United States)

    Jeffrey H. Gove; Mark J. Ducey

    2014-01-01

    Management guides for uneven-aged forest stands periodically need to be revisited and updated based on new information and methods. The current silvicultural guide for uneven-aged spruce-fir management in Maine and the northeast (Frank, R.M. and Bjorkbom, J.C. 1973 A silvicultural guide for spruce-fir in the northeast. General Technical Report NE-6, Forest Service. U.S...

  14. Thrust stand for vertically oriented electric propulsion performance evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, Trevor [University of Tennessee Space Institute, Tullahoma, Tennessee 37388 (United States); Polzin, Kurt A. [NASA, Marshall Space Flight Center, Huntsville, Alabama 35812 (United States)

    2010-11-15

    A variation of a hanging pendulum thrust stand capable of measuring the performance of an electric thruster operating in the vertical orientation is presented. The vertical orientation of the thruster dictates that the thruster must be horizontally offset from the pendulum pivot arm, necessitating the use of a counterweight system to provide a neutrally stable system. Motion of the pendulum arm is transferred through a balance mechanism to a secondary arm on which deflection is measured. A noncontact light-based transducer is used to measure displacement of the secondary beam. The members experience very little friction, rotating on twisting torsional pivots with oscillatory motion attenuated by a passive, eddy-current damper. Displacement is calibrated using an in situ thrust calibration system. Thermal management and self-leveling systems are incorporated to mitigate thermal and mechanical drifts. Gravitational force and torsional spring constants associated with flexure pivots provide restoring moments. An analysis of the design indicates that the thrust measurement range spans roughly four decades, with the stand capable of measuring thrust up to 12 N for a 200 kg thruster and up to approximately 800 mN for a 10 kg thruster. Data obtained from calibration tests performed using a 26.8 lbm simulated thruster indicated a resolution of 1 mN on 100 mN level thrusts, while those tests conducted on a 200 lbm thruster yielded a resolution of roughly 2.5 mN at thrust levels of 0.5 N and greater.

  15. Thrust Stand for Vertically Oriented Electric Propulsion Performance Evaluation

    Science.gov (United States)

    Moeller, Trevor; Polzin, Kurt A.

    2010-01-01

    A variation of a hanging pendulum thrust stand capable of measuring the performance of an electric thruster operating in the vertical orientation is presented. The vertical orientation of the thruster dictates that the thruster must be horizontally offset from the pendulum pivot arm, necessitating the use of a counterweight system to provide a neutrally-stable system. Motion of the pendulum arm is transferred through a balance mechanism to a secondary arm on which deflection is measured. A non-contact light-based transducer is used to measure displacement of the secondary beam. The members experience very little friction, rotating on twisting torsional pivots with oscillatory motion attenuated by a passive, eddy current damper. Displacement is calibrated using an in situ thrust calibration system. Thermal management and self-leveling systems are incorporated to mitigate thermal and mechanical drifts. Gravitational restoring force and torsional spring constants associated with flexure pivots provide restoring moments. An analysis of the design indicates that the thrust measurement range spans roughly four decades, with the stand capable of measuring thrust up to 12 N for a 200 kg thruster and up to approximately 800 mN for a 10 kg thruster. Data obtained from calibration tests performed using a 26.8 lbm simulated thruster indicated a resolution of 1 mN on 100 mN-level thrusts, while those tests conducted on 200 lbm thruster yielded a resolution of roughly 2.5 micro at thrust levels of 0.5 N and greater.

  16. Thrust stand for vertically oriented electric propulsion performance evaluation

    International Nuclear Information System (INIS)

    Moeller, Trevor; Polzin, Kurt A.

    2010-01-01

    A variation of a hanging pendulum thrust stand capable of measuring the performance of an electric thruster operating in the vertical orientation is presented. The vertical orientation of the thruster dictates that the thruster must be horizontally offset from the pendulum pivot arm, necessitating the use of a counterweight system to provide a neutrally stable system. Motion of the pendulum arm is transferred through a balance mechanism to a secondary arm on which deflection is measured. A noncontact light-based transducer is used to measure displacement of the secondary beam. The members experience very little friction, rotating on twisting torsional pivots with oscillatory motion attenuated by a passive, eddy-current damper. Displacement is calibrated using an in situ thrust calibration system. Thermal management and self-leveling systems are incorporated to mitigate thermal and mechanical drifts. Gravitational force and torsional spring constants associated with flexure pivots provide restoring moments. An analysis of the design indicates that the thrust measurement range spans roughly four decades, with the stand capable of measuring thrust up to 12 N for a 200 kg thruster and up to approximately 800 mN for a 10 kg thruster. Data obtained from calibration tests performed using a 26.8 lbm simulated thruster indicated a resolution of 1 mN on 100 mN level thrusts, while those tests conducted on a 200 lbm thruster yielded a resolution of roughly 2.5 mN at thrust levels of 0.5 N and greater.

  17. Ecosystem Responses to Partial Harvesting in Eastern Boreal Mixedwood Stands

    Directory of Open Access Journals (Sweden)

    Brian D. Harvey

    2013-05-01

    Full Text Available Partial harvesting has been proposed as a key aspect to implementing ecosystem management in the Canadian boreal forest. We report on a replicated experiment located in boreal mixedwoods of Northwestern Quebec. In the winter of 2000–2001, two partial harvesting treatments, one using a dispersed pattern, and a second, which created a (400 m2 gap pattern, were applied to a 90-year-old aspen-dominated mixed stand. The design also included a clear cut and a control. Over the course of the following eight years, live tree, coarse woody debris, regeneration and ground beetles were inventoried at variable intervals. Our results indicate that all harvesting treatments created conditions favorable to balsam fir (Abies balsamea sapling growth and trembling aspen (Populus tremuloides sapling recruitment. However, balsam fir and trembling aspen regeneration and ground beetles response to gap cuts were closer to patterns observed in clear cuts than in dispersed harvesting. The underlying reasons for these differing patterns can be linked to factors associated with the contrasting light regimes created by the two partial harvesting treatments. The study confirms that partially harvesting is an ecologically sound approach in boreal mixedwoods and could contribute to maintaining the distribution of stand ages at the landscape level.

  18. Manager's handbook for northern hardwoods in the north-central states.

    Science.gov (United States)

    Carl H. Tubbs

    1977-01-01

    Provides a key for the resource manager to use in choosing silvicultural practices for the management of northern hardwoods. Control of stand composition, growth, and stand establishment for timber production, water, wildlife, and recreation are discussed.

  19. Residual liquefaction of seabed under standing waves

    DEFF Research Database (Denmark)

    Kirca, V.S. Ozgur; Sumer, B. Mutlu; Fredsøe, Jørgen

    2013-01-01

    This paper presents the results of an experimental study of the seabed liquefaction beneath standing waves. Silt (with d50 =0.070mm) was used in the experiments. Two kinds of measurements were carried out: pore water pressure measurements and water surface elevation measurements. These measurements...... were synchronized with video recording of the liquefaction process from the side. The ranges of the various quantities in the experiments were wave height H= 5.9-12.0 cm, wave period T= 1.09s, and water depth h=30 cm. The experiments show that the seabed liquefaction under standing waves, although...... qualitatively similar, show features different from that caused by progressive waves. The pore water pressure builds up (or accumulated) in the areas around the node and subsequently spreads out toward the antinodes. The experimental results imply that this transport is caused by a diffusion mechanism...

  20. Modeling natural regeneration biomass of Pinus stand

    Directory of Open Access Journals (Sweden)

    Rafael Cubas

    2016-09-01

    Full Text Available Reliable biomass data are very important in the evaluation of ecosystems, and help in understanding the contribution of forests in climate change. Variables that describe the size of the tree, like diameter and height are directly associated with biomass, which allows the use of regression models to estimate this element. Therefore, this study aimed to estimate by regression models, the biomass of different compartments of natural regeneration of trees of a Pinus taeda L. stand. The data were obtained through direct destructive method, using 100 randomly selected trees in the understory of a stand of Pinus taeda. We analyzed three arithmetical models, three logarithmic and two models developed by Stepwise process. Logarithmic equations developed by Stepwise procedure showed the best estimates of total and stems biomass. However, for needles and twigs compartments the best adjust was observed with Husch model and for root biomass Berkhout model proved to be the most suitable.

  1. The standing advisory group on safeguards implementation

    International Nuclear Information System (INIS)

    Jennekens, J.H.F.

    1982-09-01

    In 1975 the Director General of the IAEA called together ten persons from member states with nuclear programs at varying stages of development to form the Standing Advisory Group on Safeguards Implementation. The group was later expanded to twelve. The Director General asked the group to evaluate the technical objectives of Agency safeguards, assess the effectiveness and efficiency of specific safeguards operating methods in meeting these technical objectives, advise on techniques to be employed in safeguards operations, and recommend areas where further work is needed. This paper reviews the work of the Standing Advisory Group on Safeguards Implementation since its formation in 1975, summarizes the subjects that have been examined and the advice rendered, and outlines the problem areas requiring further study

  2. Nonlinear theory of localized standing waves

    OpenAIRE

    Denardo, Bruce; Larraza, Andrés; Putterman, Seth; Roberts, Paul

    1992-01-01

    An investigation of the nonlinear dispersive equations of continuum mechanics reveals localized standing-wave solutions that are domain walls between regions of different wave number. These states can appear even when the dispersion law is a single-valued function of the wave number. In addition, we calculate solutions for kinks in cutoff and noncutoff modes, as well as cutoff breather solitons. Division of Engineering and Geophysics of the Office of Basic Energy Science of U.S. DOE for su...

  3. Beam instrumentation for an ISOL test stand

    International Nuclear Information System (INIS)

    Mackenzie, G.H.; Dombsky, M.; Rawnsley, W.; Stanford, G.; Yin, Y.; Novikov, A.

    1995-09-01

    TRIUMF is constructing a test bed for the first stages of the proposed TISAC accelerated radioactive beam facility. The authors will present the requirements for the diagnostic system for this test stand and describe the design and development work underway. Scintillators, beamstops and a Faraday Cup have been tested using stable, mass analyzed, 12 keV beams of ions from mass 14 to 132. The design of a linear drive, with 10 microm resolution, for scanning wires and slits has begun

  4. Beam instrumentation for an ISOL test stand

    International Nuclear Information System (INIS)

    Mackenzie, G.H.; Dombsky, M.; Rawnsley, W.; Stanford, G.; Yin, Y.; Novikov, A.

    1995-09-01

    TRIUMF is constructing a test bed for the first stages of the proposed TISAC accelerated radioactive beam facility. We will present the requirements for the diagnostic system for this test stand and describe the design and development work underway. Scintillators, beamstops and Faraday Cup have been tested using stable, mass analyzed, 12 keV beams of ions from mass 14 to 132. The design of a linear drive, with 10 μm resolution, for scanning wires and slits has begun. (author)

  5. Down force calibration stand test report

    International Nuclear Information System (INIS)

    BOGER, R.M.

    1999-01-01

    The Down Force Calibration Stand was developed to provide an improved means of calibrating equipment used to apply, display and record Core Sample Truck (CST) down force. Originally, four springs were used in parallel to provide a system of resistance that allowed increasing force over increasing displacement. This spring system, though originally deemed adequate, was eventually found to be unstable laterally. For this reason, it was determined that a new method for resisting down force was needed

  6. Test Stand for Linear Induction Accelerator Optimization

    International Nuclear Information System (INIS)

    Ong, M; DeHope, B; Griffin, K; Goerz, D; Kihara, R; Vogtlin, G; Zentler, J M; Scarpetti, R

    2003-01-01

    Lawrence Livermore National Laboratory has designed and constructed a test stand to improve the voltage regulation in our Flash X-Ray (FXR) accelerator cell. The goal is to create a more mono-energetic electron beam that will create an x-ray source with a smaller spot size. Studying the interaction of the beam and pulse-power system with the accelerator cell will improve the design of high-current accelerators at Livermore and elsewhere. On the test stand, a standard FXR cell is driven by a flexible pulse-power system and the beam current is simulated with a switched center conductor. The test stand is fully instrumented with high-speed digitizers to document the effect of impedance mismatches when the cell is operated under various full-voltage conditions. A time-domain reflectometry technique was also developed to characterize the beam and cell interactions by measuring the impedance of the accelerator and pulse-power component. Computer models are being developed in parallel with the testing program to validate the measurements and evaluate different design changes. Both 3D transient electromagnetic and circuit models are being used

  7. Aggregating pixel-level basal area predictions derived from LiDAR data to industrial forest stands in North-Central Idaho

    Science.gov (United States)

    Andrew T. Hudak; Jeffrey S. Evans; Nicholas L. Crookston; Michael J. Falkowski; Brant K. Steigers; Rob Taylor; Halli Hemingway

    2008-01-01

    Stand exams are the principal means by which timber companies monitor and manage their forested lands. Airborne LiDAR surveys sample forest stands at much finer spatial resolution and broader spatial extent than is practical on the ground. In this paper, we developed models that leverage spatially intensive and extensive LiDAR data and a stratified random sample of...

  8. Stand structure and regeneration of harvested Araucaria araucana ...

    African Journals Online (AJOL)

    Stand structure and regeneration of harvested Araucaria araucana–Nothofagus stands in central Chile. Rafael M Navarro-Cerrillo, Fernando Olave, Francisco Moreno, Sergio de Miguel, Margarita Clemente ...

  9. Forest evaporation models: Relationships between stand growth and evaporation

    CSIR Research Space (South Africa)

    Le Maitre, David C

    1997-06-01

    Full Text Available The relationships between forest stand structure, growth and evaporation were analysed to determine whether forest evaporation can be estimated from stand growth data. This approach permits rapid assessment of the potential impacts of afforestation...

  10. Tropical forest biomass estimation from truncated stand tables.

    Science.gov (United States)

    A. J. R. Gillespie; S. Brown; A. E. Lugo

    1992-01-01

    Total aboveground forest biomass may be estimated through a variety of techniques based on commercial inventory stand and stock tables. Stand and stock tables from tropical countries commonly omit trees bellow a certain commercial limit.

  11. Modelling canopy fuel and forest stand variables and characterizing the influence of thinning in the stand structure using airborne LiDAR

    Directory of Open Access Journals (Sweden)

    A. Hevia

    2016-02-01

    Full Text Available Forest fires are a major threat in NW Spain. The importance and frequency of these events in the area suggests the need for fuel management programs to reduce the spread and severity of forest fires. Thinning treatments can contribute for fire risk reduction, because they cut off the horizontal continuity of forest fuels. Besides, it is necessary to conduct a fire risk management based on the knowledge of fuel allocation, since fire behaviour and fire spread study is dependent on the spatial factor. Therefore, mapping fuel for different silvicultural scenarios is essential. Modelling forest variables and forest structure parameters from LiDAR technology is the starting point for developing spatially explicit maps. This is essential in the generation of fuel maps since field measurements of canopy fuel variables is not feasible. In the present study, we evaluated the potential of LiDAR technology to estimate canopy fuel variables and other stand variables, as well as to identify structural differences between silvicultural managed and unmanaged P. pinaster Ait. stands. Independent variables (LiDAR metrics of greater explanatory significance were identified and regression analyses indicated strong relationships between those and field-derived variables (R2 varied between 0.86 and 0.97. Significant differences were found in some LiDAR metrics when compared thinned and unthinned stands. Results showed that LiDAR technology allows to model canopy fuel and stand variables with high precision in this species, and provides useful information for identifying areas with and without silvicultural management.

  12. STANDING CONCERTATION COMMMITTEE - ORDINARY MEETING ON 26 JUNE 2007

    CERN Multimedia

    HR Department

    2007-01-01

    The main items discussed at the meeting of the Standing Concertation Committee on 26 June 2007 included: Mutual Aid Fund The Committee took note of the annual report for 2006 by the Chairman of the Mutual Aid Fund and approved contributions to the Fund’s budget from the Management and the Staff Association and thanked the members of the Fund for their work. Administrative Circular No. 12 A (Rev. 1) - Education Fees The Committee agreed to recommend Administrative Circular No. 12 A entitled "Education Fees" to the Director-General for approval. The circular is applicable to staff, fellows and scientific associates recruited from 1st January 2007 and to staff who were recruited as Local Staff before that date. Further details of reimbursement of school fees will shortly be available in the form of Frequently Asked Questions on the HR Department website. Administrative Circular No. 31 (Rev. 1) - International Indemnity and Non-Resident Allowance The Committee agreed to reco...

  13. Modeling higher education attractiveness to stand global environment

    Directory of Open Access Journals (Sweden)

    Leonel Cezar Rodrigues

    2016-04-01

    Full Text Available Inabilities to deal with the changing environment may lead Higher Education Institutions (HEI to loose institutional attractiveness. Digital transformation requires global insertion as essential feature to institutional attractiveness. Processes for international education seem to lack the links between real environmental trends and the internal capabilities to global education. HEI managers may approach endeavors to internationalize education combining ambidextrous strategy supported by consolidated resilience capabilities. The latest ones refer to building internal value attributes to increase institutional attractiveness assuring solid standing in the global environment. In this article, a theoretical essay, we approach the problem of creating resilience as a way of backing up ambidexterity to generate institutional attractiveness. The set of value attributes, on the other hand, may originate strategic routes to strengthen internal competences and to make the institution more attractive, as a dynamic capability.

  14. Standing Concertation Commmittee - Ordinary meeting on 10 May 2007

    CERN Multimedia

    HR Department

    2007-01-01

    At its meeting on 10 May 2007, the Standing Concertation Committee discussed the Management's proposal for the revision of Annex A 1 of the Staff Rules and Regulations. Annex A 1 sets out the principles for future periodic reviews of the personnel's financial and social conditions and the revision reflects the modifications to review methods decided by the CERN Council in December 2006. The aim is to simplify the processes involved and rationalize the use of resources. The data collection process will be outsourced to a greater extent. The new methods also aim to reduce the overall time required to complete future reviews. Details of procedure will be addressed in subsequent discussions. The Committee approved the document for submission to the Tripartite Employment Conditions Forum (TREF) at its meeting on 31 May and 1 June 2007.

  15. Evaluation of site impacts associated with three silvicultural prescriptions in an upland hardwood stand in northern Alabama, USA

    Science.gov (United States)

    Emily A. Carter; Robert B. Rummer; Bryce J. Stokes

    2006-01-01

    Soil disturbance patterns and associated changes in soil physical status were measured in a study that evaluated the implementation of three alternative management prescriptions in an upland hardwood stand in northern Alabama, USA. Management prescriptions applied in this study consisted of a clear-cut, strip cut, and deferment cut that were compared to a non-harvested...

  16. 21 CFR 880.2700 - Stand-on patient scale.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Stand-on patient scale. 880.2700 Section 880.2700... Devices § 880.2700 Stand-on patient scale. (a) Identification. A stand-on patient scale is a device intended for medical purposes that is used to weigh a patient who is able to stand on the scale platform...

  17. Facilitating the recovery of natural evergreen forests in South Africa via invader plant stands

    Directory of Open Access Journals (Sweden)

    Coert J. Geldenhuys

    2017-11-01

    dramatic effect of excluding browsing. The results support the approach to rather selectively manipulate than clear invader plant stands in the natural forest environment. This approach invests in the natural succession process rather than planting. It protects developing seedlings against browsing by stacking invader plant debris around them, rather than protecting them by means of costly fencing. This forest recovery process through nurse stands of invasive species can be managed, with additional benefits: Indigenous tree species provide for better streambank stability; and the practice provides for local job creation over a 10-year period for harvesting poles and firewood from the manipulative conversion process.

  18. Regional Instability in the Abundance of Open Stands in the Boreal Forest of Eastern Canada

    Directory of Open Access Journals (Sweden)

    Rija Rapanoela

    2016-05-01

    Full Text Available Fires are a key disturbance of boreal forests. In fact, they are the main source of renewal and evolution for forest stands. The variability of fire through space and time results in a diversified forest mosaic, altering their species composition, structure and productivity. A resilient forest is assumed to be in a state of dynamic equilibrium with the fire regime, so that the composition, age structure and succession stages of forests should be consistent with the fire regime. Dense spruce-moss stands tend, however, to diminish in favour of more open stands similar to spruce-lichen stands when subjected to more frequent and recurring disturbances. This study therefore focused on the effects of spatial and temporal variations in burn rates on the proportion of open stands over a large geographic area (175,000 km2 covered by black spruce (Picea mariana (Mill. Britton, Sterns, Poggenb.. The study area was divided into 10 different zones according to burn rates, as measured using fire-related data collected between 1940 and 2006. To test if the abundance of open stands was unstable over time and not in equilibrium with the current fire regime, forest succession was simulated using a landscape dynamics model that showed that the abundance of open stands should increase progressively over time in zones where the average burn rate is high. The proportion of open stands generated during a specific historical period is correlated with the burn rate observed during the same period. Rising annual burn rates over the past two decades have thereby resulted in an immediate increase in the proportion of open stands. There is therefore a difference between the current proportion of open stands and the one expected if vegetation was in equilibrium with the disturbance regime, reflecting an instability that may significantly impact the way forest resources are managed. It is apparent from this study that forestry planning should consider the risks associated

  19. Stand structure and dead wood characterization in cork forest of Calabria region (southern Italy

    Directory of Open Access Journals (Sweden)

    Barreca L

    2010-07-01

    Full Text Available The cork forests are one the most interesting forest ecosystems in the Mediterranean area. Their distribution and ecological characteristics have undergone a significant transformation after the significant changes following the development and establishment of agricultural crops. Currently, only a few stands, which survive in hard to reach places, prove the wide spread distribution of this species was also in the recent past. This study describes the stand structure of some cork forests in Calabria region (southern Italy. In order, to characterize the vertical structure Latham index has been applied, while for the description of the horizontal distribution NBSI group indices has been used. Detailed surveys on dead wood were also conducted determining the occurring volume and its decay stage according to the decay classes system proposed by Hunter. The aim of this study is to provide guidelines for sustainable management of cork forests, improving and promoting the structural complexity and functional efficiency of these forest stands.

  20. Predicting temperate forest stand types using only structural profiles from discrete return airborne lidar

    Science.gov (United States)

    Fedrigo, Melissa; Newnham, Glenn J.; Coops, Nicholas C.; Culvenor, Darius S.; Bolton, Douglas K.; Nitschke, Craig R.

    2018-02-01

    Light detection and ranging (lidar) data have been increasingly used for forest classification due to its ability to penetrate the forest canopy and provide detail about the structure of the lower strata. In this study we demonstrate forest classification approaches using airborne lidar data as inputs to random forest and linear unmixing classification algorithms. Our results demonstrated that both random forest and linear unmixing models identified a distribution of rainforest and eucalypt stands that was comparable to existing ecological vegetation class (EVC) maps based primarily on manual interpretation of high resolution aerial imagery. Rainforest stands were also identified in the region that have not previously been identified in the EVC maps. The transition between stand types was better characterised by the random forest modelling approach. In contrast, the linear unmixing model placed greater emphasis on field plots selected as endmembers which may not have captured the variability in stand structure within a single stand type. The random forest model had the highest overall accuracy (84%) and Cohen's kappa coefficient (0.62). However, the classification accuracy was only marginally better than linear unmixing. The random forest model was applied to a region in the Central Highlands of south-eastern Australia to produce maps of stand type probability, including areas of transition (the 'ecotone') between rainforest and eucalypt forest. The resulting map provided a detailed delineation of forest classes, which specifically recognised the coalescing of stand types at the landscape scale. This represents a key step towards mapping the structural and spatial complexity of these ecosystems, which is important for both their management and conservation.

  1. Relationship of stand age to streamwater nitrate in New Hampshire

    Science.gov (United States)

    William B. Leak; C. Wayne Martin

    1975-01-01

    Streamwater nitrate content of six watersheds during spring and summer was apparently related to stand age or age since disturbance. Nitrate concentration averaged 10.3 ppm right after cutting, dropped to a trace in medium-aged stands, and then rose again to a maximum of 4.8 ppm as stands became overmature.

  2. Production economics of harvesting young hardwood stands in central Appalachia

    Science.gov (United States)

    Yaoxiang Li; Jingxin Wang; Gary W. Miller; Joe McNeel

    2004-01-01

    Three harvesting systems of chainsaw/cable skidder, fell-buncher/grapple skidder, and harvester/forwarder were simulated in harvesting three hardwood stands of 30 to 50 years old in central Appalachia. Stands were generated by using a stand generator and harvesting prescriptions included clearcut, shelterwood cut, selective cut, diameter limit cut, and crop tree...

  3. A 3D stand generator for central Appalachian hardwood forests

    Science.gov (United States)

    Jingxin Wang; Yaoxiang Li; Gary W. Miller

    2002-01-01

    A 3-dimensional (3D) stand generator was developed for central Appalachian hardwood forests. It was designed for a harvesting simulator to examine the interactions of stand, harvest, and machine. The Component Object Model (COM) was used to design and implement the program. Input to the generator includes species composition, stand density, and spatial pattern. Output...

  4. Effect of two Notebook stands on work posture and productivity

    NARCIS (Netherlands)

    Könemann, R.; Kuijt-Evers, L.F.M.; Lingen, P. van; Sauvage, S.; Hallbeck, S.

    2009-01-01

    The aim of this study was to investigate the effect of using a notebook stand on the physical load when working with a notebook in a home environment. Sixteen subjects evaluated working with a notebook by performing three different tasks using two notebook stands and without using a notebook stand.

  5. The zero inflation of standing dead tree carbon stocks

    Science.gov (United States)

    Christopher W. Woodall; David W. MacFarlane

    2012-01-01

    Given the importance of standing dead trees in numerous forest ecosystem attributes/processes such as carbon (C) stocks, the USDA Forest Service’s Forest Inventory and Analysis (FIA) program began consistent nationwide sampling of standing dead trees in 1999. Modeled estimates of standing dead tree C stocks are currently used as the official C stock estimates for the...

  6. Stocking equations for regeneration in mixed oak stands

    Science.gov (United States)

    Songlin Fei; Kim C. Steiner; James C. Finley

    2007-01-01

    Regeneration stocking equations for mixed-oak stands were developed based on data collected from nearly 14,000 plots in the central Appalachians. Maximum stand density was identified by plotting aggregate height against number of seedlings per plot, and was used as the reference level of the average maximum stand density (100 percent stocking or A-level stocking)....

  7. Practical research of free standing rack. Seismic experiment study on full scale free standing rack

    International Nuclear Information System (INIS)

    Iwasaki, Akihisa; Nekomoto, Yoshitsugu; Morita, Hideyuki; Taniguchi, Katsuhiko; Okuno, Daisaku; Matsuoka, Toshihiro; Chigusa, Naoki

    2015-01-01

    The spent fuel taken out of a plant reactor is temporarily stored in a spent fuel rack. This fuel will often have to be stored in the rack for long periods before it can be moved to a reprocessing facility. Therefore, the spent fuel rack must have a high tolerance against big seismic loads. The free standing spent fuel rack has been developed as the optimal equipment meeting these requirements. It can be placed on the spent fuel pool floor without fixation to any support structure. Response of the free standing rack is reduced by the effect of the water and friction force on the spent fuel pool floor. For nuclear plant safety, it is necessary to understand the free standing rack behavior under earthquake in pools to verify the design of free standing racks and peripheral components. Several tests on a shaking table have been conducted on full-scale one free standing rack in air and in water, and sliding and rocking have been measured. The rack response is very complex and the study necessitates to take into account the sliding, the rocking, the effect of the water and of the arrangement of the fuel assemblies inside. (author)

  8. Stand-alone photovoltaic applications. Lessons learned

    International Nuclear Information System (INIS)

    Loois, G.; Van Hemert, B.

    1999-02-01

    The IEA Photovoltaic Power Systems Programme (PVPS) is one of the collaborative R and D agreements established within the IEA. The objective of Task III is to promote and facilitate the exchange of information and experiences in the field of PV Systems in Stand-alone and Island Applications (SAPV). The book focuses on the practical experiences gained, and does not aim to provide a complete manual on SAPV. When Task III started its activities in 1993, a collection of 50 'State of the art' projects was published in the book 'Examples of Stand-Alone Photovoltaic Systems'. This publication marked the base line for the work of the task. Now, in 1998, the showcases from each country demonstrate the lessons learned in five years of cooperation. The book consists of two parts. The first part contains eight chapters dealing with a specific aspect of stand-alone PV. The second part introduces 14 national showcase projects in a systematic presentation. Each chapter and showcase can be read independently from the rest of the book. Chapter 2, contributed by The Netherlands, analyses the market for stand-alone PV systems. It gives an overview of the 'traditional' application of stand-alone PV, which is the electrification of remote buildings and which has been addressed in depth in other publications. The focus is on the market niches of service applications that are also interesting for more densely populated areas, e.g. in industrialised countries. The United Kingdom illustrates the economic aspects in Chapter 3. Cost comparisons are made, but more important is the illustration of the non-financial considerations that make PV the preferred choice as a power source for many applications. Switzerland explores in Chapter 4 (financing aspects) different financing mechanisms, and financial policies used to overcome the initial cost barrier. Most of these approaches have been applied in developing countries rather than in the western world. Using various examples from all over the

  9. [Effects of crop tree release on stand growth and stand structure of Cunninghamia lanceolata plantation].

    Science.gov (United States)

    Wu, Jian-qiang; Wang, Yi-xiang; Yang, Yi; Zhu, Ting-ting; Zhu, Xu-dan

    2015-02-01

    Crop trees were selected in a 26-year-old even-aged Cunninghamia lanceolata plantation in Lin' an, and compared in plots that were released and unreleased to examine growth and structure responses for 3 years after thinning. Crop tree release significantly increased the mean increments of diameter and volume of individual tree by 1.30 and 1.25 times relative to trees in control stands, respectively. The increments of diameter and volume of crop trees were significantly higher than those of general trees in thinning plots, crop trees and general trees in control plots, which suggested that the responses from different tree types to crop tree release treatment were different. Crop tree release increased the average distances of crop trees to the nearest neighboring trees, reducing competition among crop trees by about 68.2%. 3-year stand volume increment for thinning stands had no significant difference with that of control stands although the number of trees was only 81.5% of the control. Crop trees in thinned plots with diameters over than 14 cm reached 18.0% over 3 years, compared with 12.0% for trees without thinning, suggesting that crop tree release benefited the larger individual trees. The pattern of tree locations in thinning plots tended to be random, complying with the rule that tree distribution pattern changes with growth. Crop tree release in C. lanceolata plantation not only promoted the stand growth, but also optimized the stand structure, benefiting crop trees sustained rapid growth and larger diameter trees production.

  10. Construction of an automated table standing

    International Nuclear Information System (INIS)

    Neira, R E; Barbero, M D; Di Giulio, E A; Folco, J F; Jiménez, G F

    2011-01-01

    In this paper, the construction of an upright stretcher designed for patients in rehabilitation. The standing back to patients' expectations of therapeutic improvement, allowing correct all the troubles of a passive long. It has been shown that this table favors not only physically but also has a psychological reach beyond the scope of physical therapy and strongly affects the recovery. At the same time, the use of an upright stretcher greatly decreases the biomechanical disorders of hospital staff in the process of recovery. Thus the problem of rehabilitation of trafficking in a comprehensive way which not only focuses on the patient's undivided attention but also includes medical and auxiliary personnel.

  11. The scientific dating of standing buildings.

    Science.gov (United States)

    Alcock, Nathaniel W

    2017-11-17

    The techniques of dendrochronology (tree-ring dating) and radiocarbon (14C) dating are described, as they are applied to historic buildings. Both rely on determining the felling dates of the trees used in their construction. For dendrochronology, the construction of master chronologies and the matching of individual ring-width sequences to them is described and, for radiocarbon dating, the use of tree-ring results in calibration. Results of dating are discussed, ranging from the cathedrals of Peterborough and Beauvais and the development of crown-post roof structures, to the dating and identification of standing medieval peasant houses, particularly those built using cruck construction.

  12. Glass temperatures in free-standing canisters

    International Nuclear Information System (INIS)

    Hardy, B.J.; Hensel, S.J.

    1993-01-01

    The waste-forms produced by the Defense Waste Processing Facility (DWPF) are subject to the requirements of the Waste Acceptance Product Specifications (WAPS). The WAPS sets the maximum post cooldown temperature of the waste-form glass at 400 degrees C. This criterion must be satisfied for the ambient conditions and heat generation rates expected for the waste-forms. As part of the work described in task plan, WSRC-RP-93-1177, Rev. 0, a computer model was used to calculate the maximum glass temperatures in free standing wasteforms for a variety of ambient temperatures and heat generation rates

  13. Construction of an automated table standing

    Science.gov (United States)

    Neira, R. E.; Barbero, M. D.; Di Giulio, E. A.; Folco, J. F.; Jiménez, G. F.

    2011-12-01

    In this paper, the construction of an upright stretcher designed for patients in rehabilitation. The standing back to patients' expectations of therapeutic improvement, allowing correct all the troubles of a passive long. It has been shown that this table favors not only physically but also has a psychological reach beyond the scope of physical therapy and strongly affects the recovery. At the same time, the use of an upright stretcher greatly decreases the biomechanical disorders of hospital staff in the process of recovery. Thus the problem of rehabilitation of trafficking in a comprehensive way which not only focuses on the patient's undivided attention but also includes medical and auxiliary personnel.

  14. SSRL photocathode RF gun test stand

    International Nuclear Information System (INIS)

    Hernandez, M.; Baltay, M.; Boyce, A.

    1995-01-01

    A photocathode RF gun test stand designed for the production and study of high brightness electron beams will be constructed at SSRL. The beam will be generated from a laser driven third generation photocathode RF gun being developed in collaboration with BNL, LBL, and UCLA. The 3-5 [MeV] beam from the gun will be accelerated using a SLAC three meter S-band accelerator section, in order to achieve the desired low emittance beam, emittance compensation with solenoidal focusing will be employed

  15. Droplets bouncing on a standing wave field

    Science.gov (United States)

    Pucci, Giuseppe; Tambasco, Lucas; Harris, Daniel; Bush, John

    2017-11-01

    A liquid bath subject to a vertical vibration becomes unstable to standing surface waves at a critical vibrational acceleration known as the Faraday threshold. We examine the behavior of a millimetric droplet bouncing on the surface of a quasi-one-dimensional fluid channel above the Faraday threshold. We identify a sequence of bifurcations that occurs as the vibrational acceleration is increased progressively, ultimately leading to the erratic, diffusive motion of the droplet along the length of the channel. A simple theoretical model is presented. This work was supported by the US National Science Foundation through Grants CMMI-1333242 and DMS-1614043.

  16. Management

    OpenAIRE

    Daft, Richard L.; Kendrick, Martyn; Vershinina, Natalia

    2010-01-01

    The market-leading textbook for principles of management courses reaches a new level with Richard L. Daft being joined by Martyn Kendrick and Natalia Vershinina (both Leicester Business School) to provide an unparalleled resource for students in Europe, the Middle East and Africa (EMEA). After listening to the requirements of lecturers, the authors have maintained the same comprehensive coverage and structure of the original work but carefully threaded in new EMEA and wider global examples an...

  17. A Pine Is a Pine and a Spruce Is a Spruce--The Effect of Tree Species and Stand Age on Epiphytic Lichen Communities.

    Science.gov (United States)

    Bäcklund, Sofia; Jönsson, Mari; Strengbom, Joachim; Frisch, Andreas; Thor, Göran

    2016-01-01

    With an increasing demand for forest-based products, there is a growing interest in introducing fast-growing non-native tree species in forest management. Such introductions often have unknown consequences for native forest biodiversity. In this study, we examine epiphytic lichen species richness and species composition on the trunks of non-native Pinus contorta and compare these to the native Pinus sylvestris and Picea abies in managed boreal forests in northern Sweden across a chronosequence of age classes. Overall, we recorded a total of 66,209 lichen occurrences belonging to 57 species in the 96 studied forest stands. We found no difference in species richness of lichens between stands of P. contorta and P. sylvestris, but stands of P. abies had higher total species richness. However, species richness of lichens in stands of P. abies decreased with increasing stand age, while no such age effect was detected for P. contorta and P. sylvestris. Lichen species composition progressively diverged with increasing stand age, and in 30-year-old stands all three tree species showed species-specific assemblages. Epiphytic lichen assemblages in stands of 30-year-old P. contorta were influenced by greater basal area, canopy closure, and average diameter at breast height, P. abies stands by higher branch density and canopy closure, and stands of P. sylvestris by greater bark crevice depth. Differences in lichen species richness and composition were mainly explained by canopy closure and habitat availability, and the greater canopy closure in mature P. abies stands promoted the colonization and growth of calicioid lichen species. Our results indicate that the non-native P. contorta have similar species richness as the native P. sylvestris. The main difference in lichen species richness and composition is between P. abies and Pinus spp. in managed forests of boreal Sweden.

  18. A Pine Is a Pine and a Spruce Is a Spruce--The Effect of Tree Species and Stand Age on Epiphytic Lichen Communities.

    Directory of Open Access Journals (Sweden)

    Sofia Bäcklund

    Full Text Available With an increasing demand for forest-based products, there is a growing interest in introducing fast-growing non-native tree species in forest management. Such introductions often have unknown consequences for native forest biodiversity. In this study, we examine epiphytic lichen species richness and species composition on the trunks of non-native Pinus contorta and compare these to the native Pinus sylvestris and Picea abies in managed boreal forests in northern Sweden across a chronosequence of age classes. Overall, we recorded a total of 66,209 lichen occurrences belonging to 57 species in the 96 studied forest stands. We found no difference in species richness of lichens between stands of P. contorta and P. sylvestris, but stands of P. abies had higher total species richness. However, species richness of lichens in stands of P. abies decreased with increasing stand age, while no such age effect was detected for P. contorta and P. sylvestris. Lichen species composition progressively diverged with increasing stand age, and in 30-year-old stands all three tree species showed species-specific assemblages. Epiphytic lichen assemblages in stands of 30-year-old P. contorta were influenced by greater basal area, canopy closure, and average diameter at breast height, P. abies stands by higher branch density and canopy closure, and stands of P. sylvestris by greater bark crevice depth. Differences in lichen species richness and composition were mainly explained by canopy closure and habitat availability, and the greater canopy closure in mature P. abies stands promoted the colonization and growth of calicioid lichen species. Our results indicate that the non-native P. contorta have similar species richness as the native P. sylvestris. The main difference in lichen species richness and composition is between P. abies and Pinus spp. in managed forests of boreal Sweden.

  19. A Pine Is a Pine and a Spruce Is a Spruce – The Effect of Tree Species and Stand Age on Epiphytic Lichen Communities

    Science.gov (United States)

    Bäcklund, Sofia; Jönsson, Mari; Strengbom, Joachim; Frisch, Andreas; Thor, Göran

    2016-01-01

    With an increasing demand for forest-based products, there is a growing interest in introducing fast-growing non-native tree species in forest management. Such introductions often have unknown consequences for native forest biodiversity. In this study, we examine epiphytic lichen species richness and species composition on the trunks of non-native Pinus contorta and compare these to the native Pinus sylvestris and Picea abies in managed boreal forests in northern Sweden across a chronosequence of age classes. Overall, we recorded a total of 66,209 lichen occurrences belonging to 57 species in the 96 studied forest stands. We found no difference in species richness of lichens between stands of P. contorta and P. sylvestris, but stands of P. abies had higher total species richness. However, species richness of lichens in stands of P. abies decreased with increasing stand age, while no such age effect was detected for P. contorta and P. sylvestris. Lichen species composition progressively diverged with increasing stand age, and in 30-year-old stands all three tree species showed species-specific assemblages. Epiphytic lichen assemblages in stands of 30-year-old P. contorta were influenced by greater basal area, canopy closure, and average diameter at breast height, P. abies stands by higher branch density and canopy closure, and stands of P. sylvestris by greater bark crevice depth. Differences in lichen species richness and composition were mainly explained by canopy closure and habitat availability, and the greater canopy closure in mature P. abies stands promoted the colonization and growth of calicioid lichen species. Our results indicate that the non-native P. contorta have similar species richness as the native P. sylvestris. The main difference in lichen species richness and composition is between P. abies and Pinus spp. in managed forests of boreal Sweden. PMID:26799558

  20. Growth and yield considerations and implications for alternative density management objectives and approaches

    Science.gov (United States)

    David. Marshall

    2013-01-01

    Density management through thinning is the most important tool foresters have to aff ect stand development and stand structure of existing stands. Reducing stand density by thinning increases the growing space and resource availability (e.g., light, water, and nutrients) for the remaining trees. Th is can result in increased average tree growth. More available site...

  1. Numerical Investigation of Three-dimensional Instability of Standing Waves

    Science.gov (United States)

    Zhu, Qiang; Liu, Yuming; Yue, Dick K. P.

    2002-11-01

    We study the three-dimensional instability of finite-amplitude standing waves under the influence of gravity using the transition matrix method. For accurate calculation of the transition matrices, we apply an efficient high-order spectral element method for nonlinear wave dynamics in complex domain. We consider two types of standing waves: (a) plane standing waves; and (b) standing waves in a circular tank. For the former, in addition to the confirmation of the side-band-like instability, we find a new three-dimensional instability for arbitrary base standing waves. The dominant component of the unstable disturbance is an oblique standing wave, with an arbitrary angle relative to the base flow, whose frequency is approximately equal to that of the base standing wave. Based on direct simulations, we confirm such a three-dimensional instability and show the occurrence of the Fermi-Pasta-Ulam recurrence phenomenon during nonlinear evolution. For the latter, we find that beyond a threshold wave steepness, the standing wave with frequency Ω becomes unstable to a small three-dimensional disturbance, which contains two dominant standing-wave components with frequencies ω1 and ω_2, provided that 2Ω ω1 + ω_2. The threshold wave steepness is found to decrease/increase as the radial/azimuthal wavenumber of the base standing wave increases. We show that the instability of standing waves in rectangular and circular tanks is caused by third-order quartet resonances between base flow and disturbance.

  2. Science stand-up at CERN

    CERN Multimedia

    Stephanie McClellan

    2013-01-01

    Supported by host Helen Keen from BBC4’s "It is Rocket Science", six amateur performers from CERN (Sam Gregson, Alex Brown, Benjamin Frisch, Claire Lee, Hugo Day and Clara Nellist) were joined on stage by geek-pop sensation Jonny Berliner and comedians Pierre Novellie and Lieven Scheire for a night of science stand-up comedy.   Host Helen Keen starts off the comedy event. (Image: Piotr Traczyk). Like the genesis of most great things, the LHComedy event began as an idea. Sam Gregson, a PhD student at CERN, had been a regular at the Cambridge Bright Club. This public engagement event promotes scientists’ research through stand-up comedy. Sam thought, “If people came to watch Bright Club at Cambridge and enjoyed the research, why can’t we do it at the biggest scientific experiment in the world?” Sam’s idea gained momentum after being introduced to FameLab participants at CERN. Similar to Bright Club, FameLab is a com...

  3. Engineering design of vertical test stand cryostat

    International Nuclear Information System (INIS)

    Suhane, S.K.; Sharma, N.K.; Raghavendra, S.; Joshi, S.C.; Das, S.; Kush, P.K.; Sahni, V.C.; Gupta, P.D.; Sylvester, C.; Rabehl, R.; Ozelis, J.

    2011-01-01

    Under Indian Institutions and Fermilab collaboration, Raja Ramanna Centre for Advanced Technology and Fermi National Accelerator Laboratory are jointly developing 2K Vertical Test Stand (VTS) cryostats for testing SCRF cavities at 2K. The VTS cryostat has been designed for a large testing aperture of 86.36 cm for testing of 325 MHz Spoke resonators, 650 MHz and 1.3 GHz multi-cell SCRF cavities for Fermilab's Project-X. Units will be installed at Fermilab and RRCAT and used to test cavities for Project-X. A VTS cryostat comprises of liquid helium (LHe) vessel with internal magnetic shield, top insert plate equipped with cavity support stand and radiation shield, liquid nitrogen (LN 2 ) shield and vacuum vessel with external magnetic shield. The engineering design and analysis of VTS cryostat has been carried out using ASME B and PV Code and Finite Element Analysis. Design of internal and external magnetic shields was performed to limit the magnetic field inside LHe vessel at the cavity surface 2 shield has been performed to check the effectiveness of LN 2 cooling and for compliance with ASME piping code allowable stresses.

  4. Standing Stability in Knee Osteoarthritis Patients

    Directory of Open Access Journals (Sweden)

    M.T. Karimi

    2016-09-01

    Full Text Available Aims: Being prevalent in the more than 40 years old persons, the knee osteoarthritis is one of the main factors in the function system failure mainly affecting their life. There is a type of instability in the persons with knee osteoarthritis, which is an increase in the domain and frequency of body pressure center. The aim of the present study was to compare the standing stability parameters in persons with knee osteoarthritis and healthy persons. Instrument & Methods: In this case-control, 15 patients with knee osteoarthritis referred to the physiotherapy clinic of the rehabilitation center and Al-Zahra hospital were studied in the muscle-skeletal research center of Isfahan University of Medical Sciences in 2015. The subjects were selected via stratified sampling method. As control group, 15 healthy persons were also studied in Isfahan. Total path length and the domain and frequency of pressure center in different directions were measured to assess the stability. Data was analyzed by SPSS 19 software using descriptive statistics and paired T test. Findings: There were increases in the mean movement domain and the frequency of pressure center in the anterior-posterior and the internal-external directions, as well as in the total path proceeded by the pressure center in the internal-external direction, in the persons with knee osteoarthritis than the healthy persons (p0.05. Conclusion: Standing stability and balance in persons with knee osteoarthritis decreases compared to healthy persons.

  5. Radial Growth Response of Black Spruce Stands Ten Years after Experimental Shelterwoods and Seed-Tree Cuttings in Boreal Forest

    Directory of Open Access Journals (Sweden)

    Miguel Montoro Girona

    2016-10-01

    Full Text Available Partial cutting is thought to be an alternative to achieve sustainable management in boreal forests. However, the effects of intermediate harvest intensity (45%–80% on growth remain unknown in black spruce (Picea mariana (Mill. B.S.P. stands, one of the most widely distributed boreal species with great commercial interest. In this study, we analysed the effect of three experimental shelterwood and one seed-tree treatments on tree radial growth in even-aged black spruce stands, 10 years after intervention. Our results show that radial growth response 8–10 years after cutting was 41% to 62% higher than in untreated plots, with stand structure, treatment, tree position relative to skidding trails, growth before cutting and time having significant interactions. The stand structure conditioned tree growth after cutting, being doubled in younger and denser stands. Tree spatial position had a pronounced effect on radial growth; trees at the edge of the skidding trails showed twice the increase in growth compared to interior trees. Dominant trees before cutting located close to the skidding trails manifested the highest growth response after cutting. This research suggests that the studied treatments are effective to enhance radial wood production of black spruce especially in younger stands, and that the edge effect must be considered in silvicultural management planning.

  6. Inventory of aspen trees in spruce dominated stands in conservation area

    Directory of Open Access Journals (Sweden)

    Matti Maltamo

    2015-05-01

    Full Text Available Background The occurrence of aspen trees increases the conservation value of mature conifer dominated forests. Aspens typically occur as scattered individuals among major tree species, and therefore the inventory of aspens is challenging. Methods We characterized aspen populations in a boreal nature reserve using diameter distribution, spatial pattern, and forest attributes: volume, number of aspens, number of large aspen stems and basal area median diameter. The data were collected from three separate forest stands in Koli National Park, eastern Finland. At each site, we measured breast height diameter and coordinates of each aspen. The comparison of inventory methods of aspens within the three stands was based on simulations with mapped field data. We mimicked stand level inventory by locating varying numbers of fixed area circular plots both systematically and randomly within the stands. Additionally, we also tested if the use of airborne laser scanning (ALS data as auxiliary information would improve the accuracy of the stand level inventory by applying the probability proportional to size sampling to assist the selection of field plot locations. Results The results showed that aspens were always clustered, and the diameter distributions indicated different stand structures in the three investigated forest stands. The reliability of the volume and number of large aspen trees varied from relative root mean square error figures above 50% with fewer sample plots (5–10 to values of 25%–50% with 10 or more sample plots. Stand level inventory estimates were also able to detect spatial pattern and the shape of the diameter distribution. In addition, ALS-based auxiliary information could be useful in guiding the inventories, but caution should be used when applying the ALS-supported inventory technique. Conclusions This study characterized European aspen populations for the purposes of monitoring and management of boreal conservation areas. Our

  7. Spatial Structure Indices of Mature Pedunculate Oak Stands in NW Croatia

    Directory of Open Access Journals (Sweden)

    Krunoslav Indir

    2013-06-01

    Full Text Available Background and Purpose: In order to potentiate a valid comparison of forest stands, numerous indices were developed to express forest structure numerically. Each of those indices described a specific measured or calculated value. In the present study, three of the stand structure indicators, dependent on tree distance, were used: the aggregation index of Clark and Evans, the species mingling index and the diameter differentiation index. The objectives of this study were: to obtain further information about forest structure using the selected indices and to discover any limitations that the implemented indices might display. Materials and Methods: Mature pedunculate oak stands were selected as objects of the study, all located within the “Repaš – Gabajeva Greda” forest management unit, the Forest Administration of Koprivnica. The stands were aged 75 to 132 years. A systematic 500 m grid of 45 circle sample plots was established. The sample plot radius was 15, 25 or 30 meters, depending on the stand’s age. In 2001, the DBH (diameter at breast height and tree positions in regard to the centre of a plot were measured on each sample plot. The mutual distances between trees were calculated, as well as the values of the three selected stand structure indices. The two procedures of the aggregation index of Clark and Evans were calculated for all 45 sample plots. In the first case only the pedunculate oak trees were observed, and in the other all trees on the plot. The species mingling index and the diameter differentiation index were calculated for each tree in two procedures: in relatio to three and four nearest neighbouring trees. The plot/stand totals were managed as the average index of individual trees. Results: Values of the aggregation index of Clark and Evans after all trees have been observed were from 0.89 to 1.28, which indicated a random distribution of trees. In case of considering only pedunculate oak trees, the index of the plots

  8. Public Preferences Across Europe for Different Forest Stand Types as Sites for Recreation

    Directory of Open Access Journals (Sweden)

    David M. Edwards

    2012-03-01

    Full Text Available A Delphi survey involving experts in forest preference research was carried out to derive scores for the recreational value of 240 forest stand types across Europe. The survey was organized around four regional panels: Great Britain, Nordic Region, Central Europe, and Iberia. In each region, 60 forest stand types were defined according to five forest management alternatives (FMAs on a continuum of management intensity, four phases of development (establishment, young, medium, and adult, and three tree species types (conifer, broadleaved, and mixed stands of conifer and broadleaved. The resulting scores were examined using conjoint analysis to determine the relative importance of the three structural attributes (FMA, phase of development, and tree species type, and each level or component of the attributes. The findings quantify the extent to which forest visitors prefer a degree of management to unmanaged forest nature reserves across the four regions. Phase of development was shown to make the highest contribution to the recreational value of forests while the contribution of tree species type was shown to be relatively unimportant. While the results are indicative, they provide evidence to support long-term retention and low-impact silviculture in forests where recreation is a primary objective of management.

  9. Rehabilitation of Understocked Loblolly-Shortleaf Pine Stands - I. Recently Cutover Natural Stands

    Science.gov (United States)

    James B. Baker; Michael G. Shelton

    1998-01-01

    A 1988 USDA Forest Service report indicated that 22% (40 million ac) of the commercial timberland in the South was understocked (less than 60% stocking) with desirable tree species for timber production (USDA Forest Service 1988). The understocked stands are usually the result of past har-vesting practices, natural catastrophes, or regeneration fail-ures. Understocked...

  10. Transmission components of solar radiation in pine stands in relation to climatic and stand variables

    Science.gov (United States)

    Robert A. Muller

    1971-01-01

    In a new approach, transmission was studied by relating to stand biomass the ratio of incoming solar radiation beneath tree crowns to that within the atmosphere. Several assumptions were used to estimate analytically the various ways in which solar radiation penetrates through crowns of three pine species in northern California. Sunflecks accounted for much of the...

  11. Stand characteristics of 65-year-old planted and naturally regenerated stands near Sequim, Washington.

    Science.gov (United States)

    Richard E. Miller; Harry W. Anderson

    1995-01-01

    Tree numbers, height, and volume were determined in six 63- to 66-year-old plantations of coast Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) in northwest Washington. These stands resulted from the first extensive plantings of this species in the Pacific Northwest. Data from 0.25-acre plots in these...

  12. Food Irradiation. Standing legislation; Irradiacion de Alimentos. Legislacion Vigente

    Energy Technology Data Exchange (ETDEWEB)

    Verdejo S, M. [Secretaria de Salud. Subsecretaria de Regulacion y Fomento Sanitario. Direccion de Riesgos Radiologicos. Mariano Escobedo No. 366- 4o. Piso. Col. Nueva Anzures. Mexico D.F. (Mexico)

    1997-12-31

    The standing legislation in Mexico on food irradiation matter has its basis on the Constitutional Policy of the Mexican United States on the 4 Th. article by its refers to Secretary of Health, 27 Th. article to the Secretary of Energy and 123 Th. of the Secretary of Work and Social Security. The laws and regulations emanated of the proper Constitution establishing the general features which gives the normative frame to this activity. The general regulations of Radiological Safety expedited by the National Commission for Nuclear Safety and Safeguards to state the specifications which must be fulfill the industrial installations which utilizing ionizing radiations, between this line is founded, just as the requirements for the responsible of the radiological protection and the operation of these establishments. The project of Regulation of the General Health Law in matter of Sanitary Control of Benefits and Services, that in short time will be officialized, include a specific chapter on food irradiation which considers the International Organizations Recommendations and the pertaining harmonization stated for Latin America, which elaboration was in charge of specialized group where Mexico was participant. Additionally, the Secretary of Health has a Mexican Official Standard NOM-033-SSA1-1993 named `Food irradiation; permissible doses in foods, raw materials and support additives` standing from the year 1995, where is established the associated requirements to the control registers, service constancies and dose limits for different groups of foods, moreover of the specific guidelines for its process. This standard will be adequate considering the updating Regulation of Benefits and Services and the limits established the Regulation for Latin America. The associated laws that cover in general terms it would be the requirements for food irradiation although such term is not manageable. (Author)

  13. Blood pressure associates with standing balance in elderly outpatients.

    Directory of Open Access Journals (Sweden)

    Jantsje H Pasma

    Full Text Available OBJECTIVES: Assessment of the association of blood pressure measurements in supine and standing position after a postural change, as a proxy for blood pressure regulation, with standing balance in a clinically relevant cohort of elderly, is of special interest as blood pressure may be important to identify patients at risk of having impaired standing balance in routine geriatric assessment. MATERIALS AND METHODS: In a cross-sectional cohort study, 197 community-dwelling elderly referred to a geriatric outpatient clinic of a middle-sized teaching hospital were included. Blood pressure was measured intermittently (n = 197 and continuously (subsample, n = 58 before and after a controlled postural change from supine to standing position. The ability to maintain standing balance was assessed during ten seconds of side-by-side, semi-tandem and tandem stance, with both eyes open and eyes closed. Self-reported impaired standing balance and history of falls were recorded by questionnaires. Logistic regression analyses were used to examine the association between blood pressure and 1 the ability to maintain standing balance; 2 self-reported impaired standing balance; and 3 history of falls, adjusted for age and sex. RESULTS: Blood pressure decrease after postural change, measured continuously, was associated with reduced ability to maintain standing balance in semi-tandem stance with eyes closed and with increased self-reported impaired standing balance and falls. Presence of orthostatic hypotension was associated with reduced ability to maintain standing balance in semi-tandem stance with eyes closed for both intermittent and continuous measurements and with increased self-reported impaired standing balance for continuous measurements. CONCLUSION: Continuous blood pressure measurements are of additional value to identify patients at risk of having impaired standing balance and may therefore be useful in routine geriatric care.

  14. Fit in to stand out : An experience perspective on value creation

    OpenAIRE

    Högström, Claes

    2014-01-01

    In order to grow and survive, a firm must create value with consumers in ways that both fit in with consumer demands and stand out from competitors. Focusing on and understanding consumer and firm assessments of value and creation of value has become a central scope in the contemporary strategic management and marketing literature for understanding and explaining firm survival and success. Consequently, the overall aim of this thesis is to provide a conceptually and empirically grounded under...

  15. Vegetation diversity of the Scots pine stands in different forest sites in the Turawa Forest District

    OpenAIRE

    Stefańska-Krzaczek, Ewa; Pech, Paweł

    2014-01-01

    The utility of phytocenotic indices in the diagnosis and classification of forest sites might be limited because of vegetation degeneration in managed forests. However, even in secondary communities it may be possible to determine indicator species, although these may differ from typical and well known plant indicators. The aim of this work was to assess the vegetation diversity of Scots pine stands in representative forest site types along a moisture and fertility gradient. In total ...

  16. The stand prototype of minimum power NRE reactor

    International Nuclear Information System (INIS)

    Belogurov, A.I.; Grigorenko, L.N.; Mamontov, Yu.I.; Rachuk, V.S.; Stukalov, A.I.; Konyukhov, G.V.

    1995-01-01

    For ensuring of full-scale development of nuclear rocket engine (NRE) reactor was created stand prototype (reactor IRGIT?) The main differences of its are as follows: 1) Fasteners of technologies channels contents fuel assemblies in bottom are worked out the split. It is provides possibility a distance channels change without disassembly of reactor stand prototype from stand; 2) Cooling of the vessels, the moderator, the reflector and the barrel actuate is carried out by hydrogen; 3) The lower bottom modified for organization the hydrogen efflux in the form a reactor jet; 4) Radiation defence is introduced as part of stand prototype for ensuring of serviceability of stand accessories and tests routine service; 5) Each technology channels is provided of critical nozzle; 6) Control, regulation and defence of reactor has being carried out on stand system

  17. Stand model for upland forests of Southern Arkansas

    Energy Technology Data Exchange (ETDEWEB)

    Mielke, D.L.; Shugart, H.H.; West, D.C.

    1978-06-01

    A forest stand growth and composition simulator (FORAR) was developed by modifying a stand growth model by Shugart and West (1977). FORAR is a functional stand model which used ecological parameters to relate individual tree growth to environment rather than using Markov probability matrices or differential equations to determine single tree or species replacement rates. FORAR simulated tree growth and species composition of upland forests of Union County, Ark., by considering 33 tree species on a /sup 1///sub 12/ ha circular plot.

  18. Tilt table standing for reducing spasticity after spinal cord injury.

    Science.gov (United States)

    Bohannon, R W

    1993-10-01

    A patient with a T12 spinal cord injury and intractable extensor spasms of the lower extremities participated in tilt table standing trial on 5 nonconsecutive days to determine if the intervention would affect his spasticity and spasms. Each day's standing trial was followed by an immediate reduction in lower extremity spasticity (measured using the modified Ashworth scale and pendulum testing). Standing was also accompanied by a reduction in spasms that lasted until the following morning. The reduction of spasms was particularly advantageous to the performance of car transfers. Tilt table standing merits further examination as a physical treatment of spasms that accompany central nervous system lesions.

  19. Flexible integration of free-standing nanowires into silicon photonics.

    Science.gov (United States)

    Chen, Bigeng; Wu, Hao; Xin, Chenguang; Dai, Daoxin; Tong, Limin

    2017-06-14

    Silicon photonics has been developed successfully with a top-down fabrication technique to enable large-scale photonic integrated circuits with high reproducibility, but is limited intrinsically by the material capability for active or nonlinear applications. On the other hand, free-standing nanowires synthesized via a bottom-up growth present great material diversity and structural uniformity, but precisely assembling free-standing nanowires for on-demand photonic functionality remains a great challenge. Here we report hybrid integration of free-standing nanowires into silicon photonics with high flexibility by coupling free-standing nanowires onto target silicon waveguides that are simultaneously used for precise positioning. Coupling efficiency between a free-standing nanowire and a silicon waveguide is up to ~97% in the telecommunication band. A hybrid nonlinear-free-standing nanowires-silicon waveguides Mach-Zehnder interferometer and a racetrack resonator for significantly enhanced optical modulation are experimentally demonstrated, as well as hybrid active-free-standing nanowires-silicon waveguides circuits for light generation. These results suggest an alternative approach to flexible multifunctional on-chip nanophotonic devices.Precisely assembling free-standing nanowires for on-demand photonic functionality remains a challenge. Here, Chen et al. integrate free-standing nanowires into silicon waveguides and show all-optical modulation and light generation on silicon photonic chips.

  20. Relationship of Tree Stand Heterogeneity and Forest Naturalness

    Directory of Open Access Journals (Sweden)

    BARTHA, Dénes

    2006-01-01

    Full Text Available The aim of our study was to investigate if compositional (tree species richness andstructural (vertical structure, age-structure, patterns of canopy closure heterogeneity of the canopylayer is related to individual naturalness criteria and to overall forest naturalness at the stand scale. Thenaturalness values of the assessed criteria (tree species composition, tree stand structure, speciescomposition and structure of shrub layer and forest floor vegetation, dead wood, effects of game, sitecharacteristics showed similar behaviour when groups of stands with different heterogeneity werecompared, regardless of the studied aspect of canopy heterogeneity. The greatest difference was foundfor criteria describing the canopy layer. Composition and structure of canopy layer, dead wood andtotal naturalness of the stand differed significantly among the stand groups showing consistentlyhigher values from homogeneous to the most heterogeneous group. Naturalness of the compositionand structure of the shrub layer is slightly but significantly higher in stands with heterogeneous canopylayer. Regarding other criteria, significant differences were found only between the homogeneous andthe most heterogeneous groups, while groups with intermediate level of heterogeneity did not differsignificantly from one extreme. However, the criterion describing effects of game got lowernaturalness values in more heterogeneous stands. Naturalness of site characteristics did not differsignificantly among the groups except for when stands were grouped based on pattern of canopyclosure. From the practical viewpoint it is shown that purposeful forestry operations affecting thecanopy layer cause changes in compositional and structural characteristics of other layers as well as inoverall stand scale forest naturalness.

  1. Carbon Sequestration Potential in Stands under the Grain for Green Program in Southwest China.

    Directory of Open Access Journals (Sweden)

    Xiangang Chen

    Full Text Available The Grain for Green Program (GGP is the largest afforestation and reforestation project in China in the early part of this century. To assess carbon sequestration in stands under the GGP in Southwest China, the carbon stocks and their annual changes in the GGP stands in the region were estimated based on the following information: (1 collected data on the annually planted area of each tree species under the GGP in Southwest China from 1999 to 2010; (2 development of empirical growth curves and corresponding carbon estimation models for each species growing in the GPP stands; and (3 parameters associated with the stands such as wood density, biomass expansion factor, carbon fraction and the change rate of soil organic carbon content. Two forest management scenarios were examined: scenario A, with no harvesting, and scenario B, with logging at the customary rotation followed by replanting. The results showed that by the years 2020, 2030, 2040, 2050 and 2060, the expected carbon storage of the GGP stands in Southwest China is 139.58 TgC, 177.50-207.55 TgC, 196.86-259.65 TgC, 240.45-290.62 TgC and 203.22-310.03 TgC (T = 1012, respectively. For the same years, the expected annual change in carbon stocks is 7.96 TgCyr-1, -7.95-5.95 TgCyr-1, -0.10-4.67 TgCyr-1, 4.31-2.24 TgCyr-1 and -0.02-1.75 TgCyr-1, respectively. This indicates that the stands significantly contribute to forest carbon sinks in this region. In 2060, the estimated carbon stocks in the seven major species of GGP stands in Southwest China are 4.16-13.01 TgC for Pinus armandii, 6.30-15.01 TgC for Pinus massoniana, 11.51-13.44 TgC for Cryptomeria fortunei, 15.94-24.13 TgC for Cunninghamia lanceolata, 28.05 TgC for Cupressus spp., 5.32-15.63 TgC for Populus deltoides and 5.87-14.09 TgC for Eucalyptus spp. The carbon stocks in these seven species account for 36.8%-41.4% of the total carbon stocks in all GGP stands over the next 50 years.

  2. The experiences of mastery of stand-by energy demand; Les experiences de MDE stand by

    Energy Technology Data Exchange (ETDEWEB)

    Schilken, P

    2001-07-01

    In the residential sector of the OECD countries, the electricity losses of domestic appliances in stand-by position represent 1.5% of the total electricity consumption. This study belongs to the SAVE project (pilot campaign of municipal utilities for an improved rational use of energy). Its aim is to observe the policies and experiments implemented by municipalities and municipal energy companies for the abatement of the electricity consumptions of stand-by origin. A working group consisting of the German Stadtwerke and some international partners have debated the possible actions and documents for an efficient information of the public. This document presents the brochures and local actions of this program. (J.S.)

  3. Effects of Initial Stand Density and Climate on Red Pine Productivity within Huron National Forest, Michigan, USA

    Directory of Open Access Journals (Sweden)

    Joseph O'Brien

    2012-12-01

    Full Text Available Changes in climate are predicted to significantly affect the productivity of trees in the Great Lakes region over the next century. Forest management decisions, such as initial stand density, can promote climatic resiliency and moderate decreased productivity through the reduction of tree competition. The influences of climate (temperature and precipitation and forest management (initial stand density on the productivity of red pine (Pinus resinosa across multiple sites within Huron National Forest, Michigan, were examined using dendrochronological methods. Two common planting regimes were compared in this analysis; low initial density (1977 trees per hectare. Low initial density stands were found to have a higher climatic resilience by combining equal or greater measures of productivity, while having a reduced sensitivity to monthly and seasonal climate, particularly to summer drought.

  4. AGR fuel management using PANTHER

    International Nuclear Information System (INIS)

    Haddock, S.A.; Parks, G.T.

    1995-01-01

    This paper describes recent improvements in the AGR fuel management methodology implemented within PANTHER and the use of the code both for stand-alone calculations and within an automatic optimisation procedure. (author)

  5. Validation of the VitaBit Sit–Stand Tracker: Detecting Sitting, Standing, and Activity Patterns

    Directory of Open Access Journals (Sweden)

    Nathalie M. Berninger

    2018-03-01

    Full Text Available Sedentary behavior (SB has detrimental consequences and cannot be compensated for through moderate-to-vigorous physical activity (PA. In order to understand and mitigate SB, tools for measuring and monitoring SB are essential. While current direct-to-customer wearables focus on PA, the VitaBit validated in this study was developed to focus on SB. It was tested in a laboratory and in a free-living condition, comparing it to direct observation and to a current best-practice device, the ActiGraph, on a minute-by-minute basis. In the laboratory, the VitaBit yielded specificity and negative predictive rates (NPR of above 91.2% for sitting and standing, while sensitivity and precision ranged from 74.6% to 85.7%. For walking, all performance values exceeded 97.3%. In the free-living condition, the device revealed performance of over 72.6% for sitting with the ActiGraph as criterion. While sensitivity and precision for standing and walking ranged from 48.2% to 68.7%, specificity and NPR exceeded 83.9%. According to the laboratory findings, high performance for sitting, standing, and walking makes the VitaBit eligible for SB monitoring. As the results are not transferrable to daily life activities, a direct observation study in a free-living setting is recommended.

  6. Using a stand-level model to predict light absorption in stands with vertically and horizontally heterogeneous canopies

    Directory of Open Access Journals (Sweden)

    David I Forrester

    2014-09-01

    Full Text Available Background Forest ecosystem functioning is strongly influenced by the absorption of photosynthetically active radiation (APAR, and therefore, accurate predictions of APAR are critical for many process-based forest growth models. The Lambert-Beer law can be applied to estimate APAR for simple homogeneous canopies composed of one layer, one species, and no canopy gaps. However, the vertical and horizontal structure of forest canopies is rarely homogeneous. Detailed tree-level models can account for this heterogeneity but these often have high input and computational demands and work on finer temporal and spatial resolutions than required by stand-level growth models. The aim of this study was to test a stand-level light absorption model that can estimate APAR by individual species in mixed-species and multi-layered stands with any degree of canopy openness including open-grown trees to closed canopies. Methods The stand-level model was compared with a detailed tree-level model that has already been tested in mixed-species stands using empirical data. Both models were parameterised for five different forests, including a wide range of species compositions, species proportions, stand densities, crown architectures and canopy structures. Results The stand-level model performed well in all stands except in the stand where extinction coefficients were unusually variable and it appears unlikely that APAR could be predicted in such stands using (tree- or stand-level models that do not allow individuals of a given species to have different extinction coefficients, leaf-area density or analogous parameters. Conclusion This model is parameterised with species-specific information about extinction coefficients and mean crown length, diameter, height and leaf area. It could be used to examine light dynamics in complex canopies and in stand-level growth models.

  7. Accuracy and Precision of Noninvasive Blood Pressure in Normo-, Hyper-, and Hypotensive Standing and Anesthetized Adult Horses.

    Science.gov (United States)

    Heliczer, N; Lorello, O; Casoni, D; Navas de Solis, C

    2016-05-01

    Blood pressure is relevant to the diagnosis and management of many medical, cardiovascular and critical diseases. The accuracy of many commonly used noninvasive blood pressure (NIBP) monitors and the accuracy of NIBP measurements in hypo- and hypertensive standing horses has not been determined. The objective of this study was to investigate the accuracy of an oscillometric BP monitor in standing horses before and during pharmacologically induced hyper- and hypotension and to compare results in standing and anesthetized horses. Eight standing mares from a research herd (SG) and eight anesthetized horses from a hospital population (AG). Prospective experimental and observational studies. Invasive blood pressure (IBP) and NIBP, corrected to heart level, were measured simultaneously. In the SG hyper- and hypotension were induced by administration of phenylephrine (3 μg/kg/min IV for 15 minutes) and acepromazine (0.05 mg/kg IV), respectively. In the AG NIBP and IBP were recorded during regular hospital procedures. There was a significant correlation between mean NIBP and IBP in standing (R = 0.88, P horses (R = 0.81, P horses, but in the SG significant correlation between NIBP and IBP was only detected for the normotensive phase. While the evaluated oscillometric BP device allowed estimation of BP and adequately differentiated marked trends, the accuracy and precision were low in standing horses. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  8. Species diversity of polyporoid and corticioid fungi in northern hardwood forests with differing management histories

    Science.gov (United States)

    Daniel L. Lindner; Harold H., Jr. Burdsall; Glen R. Stanosz

    2006-01-01

    Effects of forest management on fungal diversity were investigated by sampling fruit bodies of polyporoid and corticioid fungi in forest stands that have different management histories. Fruit bodies were sampled in 15 northern hardwood stands in northern Wisconsin and the upper peninsula of Michigan. Sampling was conducted in five old-growth stands, five uneven-age...

  9. Temporal changes in vegetation of a virgin beech woodland remnant: stand-scale stability with intensive fine-scale dynamics governed by stand dynamic events

    Directory of Open Access Journals (Sweden)

    Tibor Standovár

    2017-03-01

    Full Text Available The aim of this resurvey study is to check if herbaceous vegetation on the forest floor exhibits overall stability at the stand-scale in spite of intensive dynamics at the scale of individual plots and stand dynamic events (driven by natural fine scale canopy gap dynamics. In 1996, we sampled a 1.5 ha patch using 0.25 m² plots placed along a 5 m × 5 m grid in the best remnant of central European montane beech woods in Hungary. All species in the herbaceous layer and their cover estimates were recorded. Five patches representing different stand developmental situations (SDS were selected for resurvey. In 2013, 306 plots were resurveyed by using blocks of four 0.25 m² plots to test the effects of imperfect relocation. We found very intensive fine-scale dynamics in the herbaceous layer with high species turnover and sharp changes in ground layer cover at the local-scale (< 1 m2. A decrease in species richness and herbaceous layer cover, as well as high species turnover, characterized the closing gaps. Colonization events and increasing species richness and herbaceous layer cover prevailed in the two newly created gaps. A pronounced decrease in the total cover, but low species turnover and survival of the majority of the closed forest specialists was detected by the resurvey at the stand-scale. The test aiming at assessing the effect of relocation showed a higher time effect than the effect of imprecise relocation. The very intensive fine-scale dynamics of the studied beech forest are profoundly determined by natural stand dynamics. Extinction and colonisation episodes even out at the stand-scale, implying an overall compositional stability of the herbaceous vegetation at the given spatial and temporal scale. We argue that fine-scale gap dynamics, driven by natural processes or applied as a management method, can warrant the survival of many closed forest specialist species in the long-run. Nomenclature: Flora Europaea (Tutin et al. 2010 for

  10. Development of a microprocessor controller for stand-alone photovoltaic power systems

    Science.gov (United States)

    Millner, A. R.; Kaufman, D. L.

    1984-01-01

    A controller for stand-alone photovoltaic systems has been developed using a low power CMOS microprocessor. It performs battery state of charge estimation, array control, load management, instrumentation, automatic testing, and communications functions. Array control options are sequential subarray switching and maximum power control. A calculator keypad and LCD display provides manual control, fault diagnosis and digital multimeter functions. An RS-232 port provides data logging or remote control capability. A prototype 5 kW unit has been built and tested successfully. The controller is expected to be useful in village photovoltaic power systems, large solar water pumping installations, and other battery management applications.

  11. Developing a mobile stand alone photovoltaic generator

    International Nuclear Information System (INIS)

    Soler-Bientz, R.; Ricalde-Cab, L.O.; Solis-Rodriguez, L.E.

    2006-01-01

    This paper describes a recent work developed to create a mobile stand alone photovoltaic generator that can be easily relocated in remote areas to evaluate the feasibility of photovoltaic energy applications. A set of sensors were installed to monitor the electric current and voltage of the energy generated, the energy stored and the energy used by the loads that may be connected to the system. Other parameters like solar radiations (both on the horizontal and on the photovoltaic generation planes) and temperatures (of both the environment and the photovoltaic module) were monitored. This was done while considering the important role of temperature in the photovoltaic module performance. Finally, a measurement and communication hardware was installed to interface the system developed with a conventional computer. In this way, the performance of the overall system in real rural conditions could be evaluated efficiently. Visual software that reads, visualizes and saves the data generated by the system was also developed by means of the LabVIEW programming environment

  12. Visual evoked responses during standing and walking

    Directory of Open Access Journals (Sweden)

    Klaus Gramann

    2010-10-01

    Full Text Available Human cognition has been shaped both by our body structure and by its complex interactionswith its environment. Our cognition is thus inextricably linked to our own and others’ motorbehavior. To model brain activity associated with natural cognition, we propose recording theconcurrent brain dynamics and body movements of human subjects performing normal actions.Here we tested the feasibility of such a mobile brain/body (MoBI imaging approach byrecording high-density electroencephalographic (EEG activity and body movements of subjectsstanding or walking on a treadmill while performing a visual oddball response task. Independentcomponent analysis (ICA of the EEG data revealed visual event-related potentials (ERPs thatduring standing, slow walking, and fast walking did not differ across movement conditions,demonstrating the viability of recording brain activity accompanying cognitive processes duringwhole body movement. Non-invasive and relatively low-cost MoBI studies of normal, motivatedactions might improve understanding of interactions between brain and body dynamics leadingto more complete biological models of cognition.

  13. Brookhaven National Laboratory electron beam test stand

    International Nuclear Information System (INIS)

    Pikin, A.; Alessi, J.; Beebe, E.; Kponou, A.; Prelec, K.; Snydstrup, L.

    1998-01-01

    The main purpose of the electron beam test stand (EBTS) project at the Brookhaven National Laboratory is to build a versatile device to develop technologies that are relevant for a high intensity electron beam ion source (EBIS) and to study the physics of ion confinement in a trap. The EBTS will have all the main attributes of EBIS: a 1-m-long, 5 T superconducting solenoid, electron gun, drift tube structure, electron collector, vacuum system, ion injection system, appropriate control, and instrumentation. Therefore it can be considered a short prototype of an EBIS for a relativistic heavy ion collider. The drift tube structure will be mounted in a vacuum tube inside a open-quotes warmclose quotes bore of a superconducting solenoid, it will be at room temperature, and its design will employ ultrahigh vacuum technology to reach the 10 -10 Torr level. The first gun to be tested will be a 10 A electron gun with high emission density and magnetic compression of the electron beam. copyright 1998 American Institute of Physics

  14. RAMSES stands guard over the accelerator chain

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    RAMSES, the system that is used to monitor radiation at the LHC, CNGS, CTF3 and n-TOF facilities, will soon be installed at strategic points in the accelerator chain, replacing the older monitoring system ARCON. The replacement programme has already begun.   RAMSES (which stands for “Radiation Monitoring System for the Environment and Safety”) is designed to protect workers, the general public and the environment, both on the Organization’s site and in the surrounding areas. It is currently operational on all the LHC sites and at CTF3, CNGS and n-TOF, while the remaining sites are still equipped with the ARCON (Area CONtroller) system. Daniel Perrin, head of the Instrumentation and Logistics Section of the HSE Unit's Radiation Protection Group, explains: “ARCON was designed for the old LEP accelerator and dates back to the early 1980s, while RAMSES is a much more recent design intended specifically for the LHC. With 389 detectors distributed across 124 mea...

  15. F-15B ACTIVE test stand

    Science.gov (United States)

    1995-01-01

    This November 13, 1995, photograph of the underside of the F-15 Advanced Controls Technology for Integrated Vehicles (ACTIVE) at NASA's Dryden Flight Research Center, Edwards, California, shows the thrust stand being used for ground testing of a new thrust-vectoring concept. The twin-engine F-15 research aircraft is equipped with new Pratt & Whitney nozzles that can turn up to 20 degrees in any direction. They give the aircraft thrust control in the pitch (up and down) and yaw (left and right) directions. This will reduce drag and increase fuel economy or range as compared with conventional aerodynamic controls, which increase the retarding forces (drag) acting upon the aircraft. Ground testing during the first two weeks of November 1995 went well, and flight tests began in March 1996. These tests could result in significant performance increases for military and commercial aircraft. The research program is the product of a collaborative effort by NASA, the Air Force's Wright Laboratory, Pratt & Whitney, and McDonnell Douglas Aerospace.

  16. Release of dissolved 85Kr by standing

    International Nuclear Information System (INIS)

    Ootsuka, Norikatsu; Yamamoto, Tadatoshi; Tsukui, Kohei

    1986-01-01

    The experiments on the release of dissolved 85 Kr by standing at room temperature were carried out to examine the influence of liquid level in a sampler and properties of solvent on the release efficiency. Six kinds of organic solvents as well as water were taken as solvents. The half-life period in case of the decrease in concentration of the dissolved 85 Kr which was used as an index of release efficiency, was proportional to the liquid level in the sampler and was inversely proportional to the diffusion coefficient of Kr gas in solvent. For organic solvents belonging to homologous series, the half-life period became longer with increasing the carbon number of solvent molecule. From the relationship between the half-life period and the carbon number, the release efficiency in the dissolved 85 Kr can be predicted for any commonly used solvent as a practical application. This method was found to be an effective means of removing the dissolved 85 Kr of low level though it takes rather long time. (author)

  17. Economics of thinning stagnated ponderosa pine sapling stands in the pine-grass areas of central Washington.

    Science.gov (United States)

    Robert W. Sassaman; James W. Barrett; Justin G. Smith

    1972-01-01

    Present net worth values earned by investments in precommercial thinning of stagnated ponderosa pine sapling stands are reported for three stocking levels. Thirteen timber management regimes are ranked by their returns from timber only, and 22 regimes are ranked according to their returns from timber and forage, with and without the allowable cut effect.

  18. The nature of the beast: examining climate adaptation options in forests with stand-replacing fire regimes

    Science.gov (United States)

    Joshua S. Halofsky; Daniel C. Donato; Jerry F. Franklin; Jessica E. Halofsky; David L. Peterson; Brian J. Harvey

    2018-01-01

    Building resilience to natural disturbances is a key to managing forests for adaptation to climate change. To date, most climate adaptation guidance has focused on recommendations for frequent-fire forests, leaving few published guidelines for forests that naturally experience infrequent, stand-replacing wildfires. Because most such forests are inherently resilient to...

  19. When a tree falls: Controls on wood decay predict standing dead tree fall and new risks in changing forests

    Science.gov (United States)

    Brad Oberle; Kiona Ogle; Amy E. Zanne; Christopher W. Woodall

    2018-01-01

    When standing dead trees (snags) fall, they have major impacts on forest ecosystems. Snag fall can redistribute wildlife habitat and impact public safety, while governing important carbon (C) cycle consequences of tree mortality because ground contact accelerates C emissions during deadwood decay. Managing the consequences of altered snag dynamics in changing forests...

  20. Simulating historical disturbance regimes and stand structures in old-forest ponderosa pine/Douglas-fir forests

    Science.gov (United States)

    Mike Hillis; Vick Applegate; Steve Slaughter; Michael G. Harrington; Helen Smith

    2001-01-01

    Forest Service land managers, with the collaborative assistance from research, applied a disturbance based restoration strategy to rehabilitate a greatly-altered, high risk Northern Rocky Mountain old-forest ponderosa pine-Douglas-fir stand. Age-class structure and fire history for the site have been documented in two research papers (Arno and others 1995, 1997)....

  1. Heavy thinning of ponderosa pine stands: An Arizona case study

    Science.gov (United States)

    Peter F. Ffolliott; Jr. Baker; Gerald J. Gottfried

    2000-01-01

    Growth and structural changes in a mosaic of even-aged ponderosa pine (Pinus ponderosa) stands were studied for 25 years to determine the long-term impacts of a heavy thinning treatment to a basal-area level of 25 ft2/acre. Basal area and volume growth of these stands has increased since thinning and likely will continue to...

  2. Flooding effects on stand development in cypress-tupelo

    Science.gov (United States)

    Richard F. Keim; Thomas J. Dean; Jim L. Chambers

    2013-01-01

    The effects of inundation on growth of cypress (Taxodium spp.) and tupelo (Nyssa spp.) trees have been extensively researched, but conclusions are often complicated by attendant effects on stand development. Flooding affects development of cypress-tupelo stands by limiting seedling germination and survival, truncating species...

  3. Simple Excitation of Standing Waves in Rubber Bands and Membranes

    Science.gov (United States)

    Cortel, Adolf

    2004-04-01

    Many methods to excite standing waves in strings, plates, membranes, rods, tubes, and soap bubbles have been described. Usually a loudspeaker or a vibrating reed is driven by the amplified output of an audio oscillator. A novel and simple method consists of using a tuning fork or a singing rod to excite transversal standing waves in stretched rubber membranes sprinkled with fine sand.

  4. 39 CFR 122.2 - Stand-alone special services.

    Science.gov (United States)

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Stand-alone special services. 122.2 Section 122.2 Postal Service UNITED STATES POSTAL SERVICE POST OFFICE SERVICES [DOMESTIC MAIL] SERVICE STANDARDS FOR MARKET-DOMINANT SPECIAL SERVICES PRODUCTS § 122.2 Stand-alone special services. (a) The service standard...

  5. A whole stand basal area projection model for Appalachian hardwoods

    Science.gov (United States)

    John R. Brooks; Lichun Jiang; Matthew Perkowski; Benktesh Sharma

    2008-01-01

    Two whole-stand basal area projection models were developed for Appalachian hardwood stands. The proposed equations are an algebraic difference projection form based on existing basal area and the change in age, trees per acre, and/or dominant height. Average equation error was less than 10 square feet per acre and residuals exhibited no irregular trends.

  6. Stand, Harvest, and Equipment Interactions in Simulated Harvesting Prescriptions

    Science.gov (United States)

    Jingxin Wang; W. Dale Greene; Bryce J. Stokes

    1998-01-01

    We evaluated potential interactions of stand type, harvesting method, and equipment in an experiment using interactive simulation. We examined three felling methods (chain saw, feller-buncher, harvester) and two extraction methods (grapple skidder and forwarder) performing clearcuts, sheltenvood cuts, and single-tree selection cuts in both an uneven-aged natural stand...

  7. Natural disturbance and stand development principles for ecological forestry

    Science.gov (United States)

    Jerry F. Franklin; Robert J. Mitchell; Brian J. Palik

    2007-01-01

    Foresters use natural disturbances and stand development processes as models for silvicultural practices in broad conceptual ways. Incorporating an understanding of natural disturbance and stand development processes more fully into silvicultural practice is the basis for an ecological forestry approach. Such an approach must include 1) understanding the importance of...

  8. The importance of spatial accuracy in characterizing stand types ...

    African Journals Online (AJOL)

    This study assessed the potential use of Landsat 7 ETM+ (15 and 30 m spatial resolutions) images to estimate forest stand attributes such as development stages, crown closure and stand types. The study evaluates the performance of spatial and image classification accuracies between Landsat images (15 and 30 m ...

  9. XML/TEI Stand-off Markup. One step beyond.

    NARCIS (Netherlands)

    Spadini, E.; Turska, Magdalena

    2018-01-01

    Stand-off markup is widely considered as a possible solution for overcoming the limitation of inline XML markup, primarily dealing with multiple overlapping hierarchies. Considering previous contributions on the subject and implementations of stand-off markup, we propose a new TEI-based model for

  10. Harvesting systems for western stand health improvement cuttings

    Science.gov (United States)

    Bruce R. Hartsough; Bryce J. Stokes; Joseph F. McNeel; William F. Watson

    1995-01-01

    A significant percentage of the forested area in the western United States is comprised of stands that have been altered over time by human activities, especially fire suppression, and are now being damaged by droughts, insect attacks, and wildfires. These stands should be returned to a condition where "biotic and abiotic influences do not threaten resource...

  11. "Growing trees backwards": Description of a stand reconstruction model

    Science.gov (United States)

    Jonathan D. Bakker; Andrew J. Sanchez Meador; Peter Z. Fule; David W. Huffman; Margaret M. Moore

    2008-01-01

    We describe an individual-tree model that uses contemporary measurements to "grow trees backward" and reconstruct past tree diameters and stand structure in ponderosa pine dominated stands of the Southwest. Model inputs are contemporary structural measurements of all snags, logs, stumps, and living trees, and radial growth measurements, if available. Key...

  12. Direct measurement of the intrinsic ankle stiffness during standing

    NARCIS (Netherlands)

    Vlutters, Mark; Vlutters, M.; Boonstra, Tjitske; Schouten, Alfred Christiaan; van der Kooij, Herman

    2015-01-01

    Ankle stiffness contributes to standing balance, counteracting the destabilizing effect of gravity. The ankle stiffness together with the compliance between the foot and the support surface make up the ankle-foot stiffness, which is relevant to quiet standing. The contribution of the intrinsic

  13. STANDING CONCERTATION COMMMITTEE - ORDINARY MEETING ON 3 APRIL 2008

    CERN Multimedia

    HR Department

    2008-01-01

    The main items discussed at the meetings of the Standing Concertation Committee on 3 April 2008 included: External mobility The Committee took note of a progress report on external mobility after a run-in period of about six months. Based on the experience gained, it was agreed to broaden the scope of the programme and in particular to extend eligibility conditions to include: All staff members whose limited duration contract will end in less than one year, as well as all those with indefinite contracts; Fellows who have been employed by CERN for more than 18 months; Doctoral students who have been in the CERN doctoral programme for more than 2.5 years; Apprentices in the final year of their apprenticeship; Ex-members of the personnel who are receiving CERN unemployment benefits. An article in the Weekly Bulletin will follow and the relevant web pages will be updated. LHC achievement awards The Committee took note of the outcome of discussions between the Management and t...

  14. First environmental data from the EUV engineering test stand

    Science.gov (United States)

    Klebanoff, Leonard E.; Malinowski, Michael E.; Grunow, Philip A.; Clift, W. Miles; Steinhaus, Chip; Leung, Alvin H.; Haney, Steven J.

    2001-08-01

    The first environmental data from the Engineering Test Stand (ETS) has been collected. Excellent control of high-mass hydrocarbons has been observed. This control is a result of extensive outgas testing of components and materials, vacuum compatible design of the ETS, careful cleaning of parts and pre-baking of cables and sub assemblies where possible, and clean assembly procedures. As a result of the hydrocarbon control, the residual ETS vacuum environment is rich in water vapor. Analysis of witness plate data indicates that the ETS environment does not pose a contamination risk to the optics in the absence of EUV irradiation. However, with EUV exposure, the water rich environment can lead to EUV- induced water oxidation of the Si-terminated Mo/Si optics. Added ethanol can prevent optic oxidation, allowing carbon growth via EUV cracking of low-level residual hydrocarbons to occur. The EUV environmental issues are understood, mitigation approaches have been validated, and EUV optic contamination appears to be manageable.

  15. Standing Concertation Committee - Ordinary meeting on 25 June 2008

    CERN Multimedia

    HR Department

    2008-01-01

    The main items discussed at the meetings of the Standing Concertation Committee on 25 June 2008 included: Mutual Aid Fund The committee took note of the annual report for 2007 by the chairman of the Mutual Aid Fund and approved contributions to the Fund’s 2008 budget from the Management and the Staff Association. Results of 2008 MARS exercise and LHC achievement awards The committee took note of the Head of HR Department’s presentation of the results of the 2008 MARS exercise and the distribution of LHC achievement awards. It was noted that these awards would be granted with effect from 1 October 2008 (see Bulletin 18&19). The results show agreement with the 2008 MARS guidelines (see Bulletin 10&11) for the advancement ceilings per career path, the number of awards for extraordinary service, as well as the distribution of steps for the recognition of merit as shown in the SCC of 27 February (see Bulletin 14&15). Follow-up of Finance Committee and Council...

  16. Standing Concertation Committee - Ordinary Meeting on 30 September 2008

    CERN Multimedia

    HR Department

    2008-01-01

    The main items discussed at the meetings of the Standing Concertation Committee on 30 September 2008 included: Part-time work as a pre-retirement measure The Committee agreed to recommend the Director-General to extend the scheme of part-time work as a pre-retirement measure by one year, i.e. until 31 December 2009. Preparation of TREF on 7 October 2008 The Committee took note that the TREF agenda would cover: Annual salary adjustment; Voluntary programmes; Five-yearly review of financial & social conditions of members of the personnel; Update on 2005 review; Preparation for 2010 review; TREF workplan 2009; Update on CHIS actuarial study. The proposals and presentations which the Management planned to present to TREF were discussed and some clarifications were agreed. Follow-up of Finance Committee and Council The Committee took note of a report by the Chairman of points related to personnel matters discussed in those committees. He mentioned in particular the annu...

  17. Average Stand Age from Forest Inventory Plots Does Not Describe Historical Fire Regimes in Ponderosa Pine and Mixed-Conifer Forests of Western North America.

    Directory of Open Access Journals (Sweden)

    Jens T Stevens

    Full Text Available Quantifying historical fire regimes provides important information for managing contemporary forests. Historical fire frequency and severity can be estimated using several methods; each method has strengths and weaknesses and presents challenges for interpretation and verification. Recent efforts to quantify the timing of historical high-severity fire events in forests of western North America have assumed that the "stand age" variable from the US Forest Service Forest Inventory and Analysis (FIA program reflects the timing of historical high-severity (i.e. stand-replacing fire in ponderosa pine and mixed-conifer forests. To test this assumption, we re-analyze the dataset used in a previous analysis, and compare information from fire history records with information from co-located FIA plots. We demonstrate that 1 the FIA stand age variable does not reflect the large range of individual tree ages in the FIA plots: older trees comprised more than 10% of pre-stand age basal area in 58% of plots analyzed and more than 30% of pre-stand age basal area in 32% of plots, and 2 recruitment events are not necessarily related to high-severity fire occurrence. Because the FIA stand age variable is estimated from a sample of tree ages within the tree size class containing a plurality of canopy trees in the plot, it does not necessarily include the oldest trees, especially in uneven-aged stands. Thus, the FIA stand age variable does not indicate whether the trees in the predominant size class established in response to severe fire, or established during the absence of fire. FIA stand age was not designed to measure the time since a stand-replacing disturbance. Quantification of historical "mixed-severity" fire regimes must be explicit about the spatial scale of high-severity fire effects, which is not possible using FIA stand age data.

  18. Average Stand Age from Forest Inventory Plots Does Not Describe Historical Fire Regimes in Ponderosa Pine and Mixed-Conifer Forests of Western North America.

    Science.gov (United States)

    Stevens, Jens T; Safford, Hugh D; North, Malcolm P; Fried, Jeremy S; Gray, Andrew N; Brown, Peter M; Dolanc, Christopher R; Dobrowski, Solomon Z; Falk, Donald A; Farris, Calvin A; Franklin, Jerry F; Fulé, Peter Z; Hagmann, R Keala; Knapp, Eric E; Miller, Jay D; Smith, Douglas F; Swetnam, Thomas W; Taylor, Alan H

    Quantifying historical fire regimes provides important information for managing contemporary forests. Historical fire frequency and severity can be estimated using several methods; each method has strengths and weaknesses and presents challenges for interpretation and verification. Recent efforts to quantify the timing of historical high-severity fire events in forests of western North America have assumed that the "stand age" variable from the US Forest Service Forest Inventory and Analysis (FIA) program reflects the timing of historical high-severity (i.e. stand-replacing) fire in ponderosa pine and mixed-conifer forests. To test this assumption, we re-analyze the dataset used in a previous analysis, and compare information from fire history records with information from co-located FIA plots. We demonstrate that 1) the FIA stand age variable does not reflect the large range of individual tree ages in the FIA plots: older trees comprised more than 10% of pre-stand age basal area in 58% of plots analyzed and more than 30% of pre-stand age basal area in 32% of plots, and 2) recruitment events are not necessarily related to high-severity fire occurrence. Because the FIA stand age variable is estimated from a sample of tree ages within the tree size class containing a plurality of canopy trees in the plot, it does not necessarily include the oldest trees, especially in uneven-aged stands. Thus, the FIA stand age variable does not indicate whether the trees in the predominant size class established in response to severe fire, or established during the absence of fire. FIA stand age was not designed to measure the time since a stand-replacing disturbance. Quantification of historical "mixed-severity" fire regimes must be explicit about the spatial scale of high-severity fire effects, which is not possible using FIA stand age data.

  19. The role of forest stand structure as biodiversity indicator

    DEFF Research Database (Denmark)

    Gao, Tian; Hedblom, Marcus; Emilsson, Tobias

    2014-01-01

    be achieved if indicators are derived from existing data. In this study, a model for classifying forest stand structures was developed and tested as an indicator of overall plant species diversity at stand level. The model combines four stand structure parameters: canopy coverage, age of canopy trees, tree...... species composition and canopy stratification. Using data from the National Inventory of Landscapes in Sweden and General Linear Mixed Model, plant species diversity (Shannon diversity index, SHDI) and composition (Sørensen-Dice index, SDI) were tested between 26 different stand structure types and nine...... soil classes. The results showed that mature stands with a stratified canopy had the highest plant species diversity across the soil classes, particularly if they comprised mixed coniferous and broadleaved species with a semi-open canopy. In contrast, young (...

  20. Impact of stand-by energy losses in electronic devices on smart network performance

    Directory of Open Access Journals (Sweden)

    Mandić-Lukić Jasmina S.

    2012-01-01

    Full Text Available Limited energy resources and environmental concerns due to ever increasing energy consumption, more and more emphasis is being put on energy savings. Smart networks are promoted worldwide as a powerful tool used to improve the energy efficiency through consumption management, as well as to enable the distributed power generation, primarily based on renewable energy sources, to be optimally explored. To make it possible for the smart networks to function, a large number of electronic devices is needed to operate or to be in their stand-by mode. The consumption of these devices is added to the consumption of many other electronic devices already in use in households and offices, thus giving rise to the overall power consumption and threatening to counteract the primary function of smart networks. This paper addresses the consumption of particular electronic devices, with an emphasis placed on their thermal losses when in stand-by mode and their total share in the overall power consumption in certain countries. The thermal losses of electronic devices in their stand-by mode are usually neglected, but it seems theoretically possible that a massive increase in their number can impact net performance of the future smart networks considerably so that above an optimum level of energy savings achieved by their penetration, total consumption begins to increase. Based on the current stand-by energy losses from the existing electronic devices, we propose that the future penetration of smart networks be optimized taking also into account losses from their own electronic devices, required to operate in stand-by mode.

  1. Tree- and Stand-Level Thinning Effects on Growth of European Beech (Fagus sylvatica L. on a Northeast- and a Southwest-Facing Slope in Southwest Germany

    Directory of Open Access Journals (Sweden)

    Daniela Diaconu

    2015-09-01

    Full Text Available Anticipated changes in climate and research findings on the drought sensitivity of beech have triggered controversial discussions about the future of European beech. We investigated the growth response of beech on the tree- and stand-level in mature stands to three different thinning intensities (no thinning, strong thinning, very strong thinning on a northeast- and southwest-facing slope in Southwest Germany. Linear mixed-effects models were formulated to describe effects on growth parameters on the tree- and stand-level (diameter, height, basal area, volume. At the stand-level, the stand basal area increment and stand volume increment were lower on the thinned plots. At the tree-level, the basal area increment significantly increased with increasing thinning intensity. The growth of individual trees was also influenced by initial tree size, the size-related rank of the tree within a stand, and by the aspect of the site. Our data indicate that growth of European beech is impaired on the southwest-facing slope with a warmer and drier climate and that a very strong thinning regime applied at advanced age can accelerate growth of European beech trees even on the warmer and drier site. Our findings, therefore, imply that in a warmer climate intensive thinning may also represent an important adaptive forest management measure in European beech stands.

  2. Converting partially-stocked aspen stands to fully-stocked stands in the Lake States: an economic analysis.

    Science.gov (United States)

    Jeffrey T. Olson; Allen L. Lundgren

    1978-01-01

    The 1968 Wisconsin Forest Survey showed large areas of aspen type that are not considered fully stocked. The economic feasibility of converting partially-stocked stands to full stocking is examined, and a rule presented for determining when a partially-stocked stand should be harvested to maximize its present value.

  3. Desk-based workers' perspectives on using sit-stand workstations: a qualitative analysis of the Stand@Work study

    NARCIS (Netherlands)

    Chau, J.Y.; Daley, M.; Srinivasan, A.; Dunn, S.; Bauman, A.E.; van der Ploeg, H.P.

    2014-01-01

    Background: Prolonged sitting time has been identified as a health risk factor. Sit-stand workstations allow desk workers to alternate between sitting and standing throughout the working day, but not much is known about their acceptability and feasibility. Hence, the aim of this study was to

  4. Multi-muscle electrical stimulation and stand training: Effects on standing.

    Science.gov (United States)

    Momeni, Kamyar; Ramanujam, Arvind; Garbarini, Erica L; Forrest, Gail F

    2018-02-15

    To examine the biomechanical and neuromuscular effects of a longitudinal multi-muscle electrical stimulation (submaximal intensities) training of the lower limbs combined with/without activity-based stand training, on the recovery of stability and function for one individual with spinal cord injury (SCI). Single-subject, longitudinal study. Neuroplasticity laboratory. A 34-year-old male, with sensory- and motor-complete SCI (C5/C6). Two consecutive interventions: 61 hours of supine, lower-limb ES (ES-alone) and 51 hours of ES combined with stand training using an overhead body-weight support system (ST + ES). Clinical measures, trunk stability, and muscle activity were assessed and compared across time points. Trunk Stability Limit (TSL) determined improvements in trunk independence. Functional clinical values increased after both interventions, with further increases post ST + ES. Post ES-alone, trunk stability was maintained at 81% body-weight (BW) loading before failure; post ST + ES, BW loading increased to 95%. TSL values decreased post ST + ES (TSL A/P =54.0 kg.cm, TSL M/L =14.5 kg.cm), compared to ES-alone (TSL A/P =8.5 kg.cm, TSL M/L =3.9 kg.cm). Trunk muscle activity decreased post ST + ES training, compared to ES-alone. Neuromuscular and postural trunk control dramatically improved following the multi-muscle ES of the lower limbs with stand training. Multi-muscle ES training paradigm of the lower limb, using traditional parameters, may contribute to the functional recovery of the trunk.

  5. The experiences of MDE stand-by; Les experiences de MDE stand-by

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-02-01

    The control of the electric power demand (MDE) is a worrying subject for many countries. The consumption of the electrical equipment in stand-by, is evaluated at 20 TWh/year for the ternary and residential sectors in Germany and 5,3 in France. Taking into account the SAVE project (Pilot campaign of municipal utilities for an improved rational use of energy), this study aims to observe the policies and the experiences of local governments in terms of energy consumption reduction. (A.L.B.)

  6. Aboveground stock of biomass and organic carbon in stands of Pinus taeda L.

    Directory of Open Access Journals (Sweden)

    Luciano Farinha Watzlawick

    2013-09-01

    Full Text Available This study aimed to estimate biomass and organic carbon in stands of Pinus taeda L. at different ages (14, 16, 19, 21, 22, 23 and 32 years and located in the municipality of General Carneiro (PR. In order to estimate biomass and organic carbon in different tree components (needles, live branches, dead branches, bark and stem wood, the destructive quantification method was used in which seven trees from each age category were randomly sampled across the stand. Stocks of biomass and organic carbon were found to vary between the different age categories, mainly as a result of existing dissimilarities between ages in association with forest management practices such as thinning, pruning and tree density per hectare.

  7. Effects on musculoskeletal pain from "Take a Stand!" - a cluster-randomized controlled trial reducing sitting time among office workers

    DEFF Research Database (Denmark)

    Danquah, Ida Høgstedt; Kloster, Stine; Holtermann, Andreas

    2017-01-01

    Objectives Prolonged sitting at work has been found to increase risk for musculoskeletal pain. The office-based intervention "Take a Stand!" was effective in reducing sitting time at work. We aimed to study the effect of the intervention on a secondary outcome: musculoskeletal pain. Methods Take...... a Stand! included 19 offices (317 workers) at four workplaces cluster randomized to intervention or control. The multicomponent intervention lasted three months and included management support, environmental changes, and local adaptation. Control participants behaved as usual. Musculoskeletal pain...

  8. Optimising mobility through the sit-to-stand activity for older people living in residential care facilities: A qualitative interview study of healthcare aide experiences.

    Science.gov (United States)

    Kagwa, Sharon A; Boström, Anne-Marie; Ickert, Carla; Slaughter, Susan E

    2018-03-01

    To explore the experience of HCAs encouraging residents living in residential care to complete the sit-to-stand activity and to identify the strategies HCAs used to integrate the activity into their daily work routines. Decreased mobility in advanced ageing is further reduced when entering a residential care facility. Interventions such as the sit-to-stand activity have been shown to have a positive effect on the mobility of older people. There is evidence to suggest that healthcare aides are able to support residents to complete the sit-to-stand activity as part of their daily work routines; however, little is known about how healthcare aides actually do this with residents living in residential care. A qualitative interview study included seven purposively sampled HCAs working in residential care facilities. Semistructured interviews were analysed using inductive qualitative content analysis. The HCAs' experience with the sit-to-stand activity was represented by the following four categories: Resident participation, Feeling misunderstood and disrespected, Time and workload, and Management involvement. HCAs identified three strategies to help them support residents to complete the sit-to-stand activity: Motivating residents, Completing activity in a group and Using time management skills. HCAs reported some encouragement from managers and cooperation from residents to complete the sit-to-stand activity with residents; however, they also felt constrained by time limitations and workload demands and they felt misunderstood and disrespected. HCAs were able to identify several strategies that helped them to integrate the sit-to-stand activity into their daily routines. This study highlights the challenges and supportive factors of implementing the sit-to-stand activity into the daily work routine of HCAs. The study also identifies the strategic role of nurse managers when implementing interventions in residential care facilities. © 2017 John Wiley & Sons Ltd.

  9. Isotope enrichment effect of gaseous mixtures in standing sound vibration

    International Nuclear Information System (INIS)

    Knesebeck, R.L.

    1984-01-01

    When standing acoustic waves are excited in a tube containing a mixture of two gases, a partial zonal fractioning of the components arises as consequence of mass transport by diffusion, driven by the thermal and pressure gradients which are associeted with the standing waves. This effect is present in each zone corresponding to a quarter wavelength, with the heavier component becoming enriched at the nodes fo the standing waves and deplected at the crests. The magnitude of the enrichment in one of the components of a binary gas mixture is given by Δω=ap 2 /lambda [b + (1-bω)] 2 . Where ω is the mass concentration of the component in the mixture, a and b are parameters which are related to molecular proprieties of the gases, p is the relative pressure amplitude of the standing wave and lambda is its wavelength. For a natural mixture of uranium hexafluorate, with 0.715% of the uranium isotope 340 an enrichment of about 2 x 10 -6 % in the concentration of this isotope is theorecticaly attainable per stage consisting of a quarter wavelenght, when a standing acoustical wave of relative pressure amplitude of 0,2 and wavelenght of 20 cm is used. Since standing acoustical waves are easely excited in gas columns, an isotope enrichment plant made of a cascade of tubes in which standing waves are excited, is presumably feasible with relatively low investment and operation costs. (Author) [pt

  10. Susceptibility of ponderosa pine, Pinus ponderosa (Dougl. Ex Laws.), to mountain pine beetle, Dendroctonus ponderosae Hopkins, attack in uneven-aged stands in the Black Hills of South Dakota and Wyoming USA

    Science.gov (United States)

    Jose F. Negron; Kurt Allen; Blaine Cook; John R. Withrow

    2008-01-01

    Mountain pine beetle, Dendroctonus ponderosae Hopkins can cause extensive tree mortality in ponderosa pine, Pinus ponderosa Dougl. ex Laws., forests in the Black Hills of South Dakota and Wyoming. Most studies that have examined stand susceptibility to mountain pine beetle have been conducted in even-aged stands. Land managers...

  11. Management of oak forests

    DEFF Research Database (Denmark)

    Löf, Magnus; Brunet, Jörg; Filyushkina, Anna

    2016-01-01

    timber production, habitats for biodiversity and cultural services, and the study analyses associated trade-offs and synergies. The three regimes were: intensive oak timber production (A), combined management for both timber production and biodiversity (B) and biodiversity conservation without management...... of wood production and cultural services. In contrast, Regime B provided a balanced delivery of timber production, biodiversity conservation and cultural services. We identified several stand-management options which provide comparatively synergistic outcomes in ecosystem services delivery. The use...

  12. Stand for testing the electrical race car engine

    Science.gov (United States)

    Baier, M.; Franiasz, J.; Mierzwa, P.; Wylenzek, D.

    2015-11-01

    An engine test stand created especially for research of electrical race car is described in the paper. The car is an aim of Silesian Greenpower project whose participants build and test electrical vehicles to take part in international races in Great Britain. The engine test stand is used to test and measure the characteristics of vehicles and their engines. It has been designed particularly to test the electric cars engineered by students of Silesian Greenpower project. The article contains a description how the test stand works and shows its versatility in many areas. The paper presents both construction of the test stand, control system and sample results of conducted research. The engine test stand was designed and modified using PLM Siemens NX 8.5. The construction of the test stand is highly modular, which means it can be used both for testing the vehicle itself or for tests without the vehicle. The test stand has its own wheel, motor, powertrain and braking system with second engine. Such solution enables verifying various concepts without changing the construction of the vehicle. The control system and measurement system are realized by enabling National Instruments product myRIO (RIO - Reconfigurable Input/Output). This controller in combination with powerful LabVIEW environment performs as an advanced tool to control torque and speed simultaneously. It is crucial as far as the test stand is equipped in two motors - the one being tested and the braking one. The feedback loop is realized by an optical encoder cooperating with the rotor mounted on the wheel. The results of tests are shown live on the screen both as a chart and as single values. After performing several tests there is a report generated. The engine test stand is widely used during process of the Silesian Greenpower vehicle design. Its versatility enables powertrain testing, wheels and tires tests, thermal analysis and more.

  13. Sit to stand activity during stroke rehabilitation.

    Science.gov (United States)

    Kerr, Andy; Dawson, Jesse; Robertson, Chris; Rowe, Philip; Quinn, Terence J

    2017-12-01

    Objectives The sit to stand (STS) movement is key to independence and commonly affected by stroke. Repetitive practice is likely to improve STS ability during rehabilitation, however current practice levels are unknown. The objective of this study was simply to count the number of STS movements performed during the rehabilitation period of stroke patients using a physical activity monitor (PAM) and test whether being observed altered outcome. Methods Participants were medically stable patients referred for rehabilitation following stroke. Participants were randomly allocated to either wear or not wear the PAM for 14 days. STS ability and general mobility were recorded before and after. Results Sixty-one patients was recruited; aged 68.4 ± 13.15 years, weight 77.12 ± 22.73 Kg, Height 1.67 ± 0.1 m, within 9 ± 9 days of their stroke and an NIHSS score of 6.4 ± 3.3. The monitored group (n = 38) performed 25.00 ± 17.24 daily STS movements. Those requiring assistance achieved 14.29 ± 16.10 per day while those independent in the movement achieved 34.10 ± 12.44. There was an overall improvement in mobility (p = 0.002) but not STS performance (p = 0.053) neither outcome was affected by group allocation (p = 0.158). Cognition and mobility at baseline explained around 50% of daily STS variability. Discussion Low levels of STS activity were recorded during the rehabilitation period of stroke patient. The mean daily STS activity was lower than reports for frail older people receiving rehabilitation, and substantially below levels recorded by community living older adults. STS repetitions may represent general physical activity and these low levels support previous reports of sedentary behavior during rehabilitation.

  14. Electromagnetic calibration system for sub-micronewton torsional thrust stand

    Science.gov (United States)

    Lam, J. K.; Koay, S. C.; Cheah, K. H.

    2017-12-01

    It is critical for a micropropulsion system to be evaluated. Thrust stands are widely recognised as the instrument to complete such tasks. This paper presents the development of an alternative electromagnetic calibration technique for thrust stands. Utilising the commercially made voice coils and permanent magnets, the proposed system is able to generate repeatable and also consistent steady-state calibration forces at over four orders of magnitude (30 - 23000 μN). The system is then used to calibrate a custom-designed torsional thrust stand, where its inherent ability in ease of setup is well demonstrated.

  15. [The use of Piezosurgery osteotomy in treatment of long-standing maxillary fractures: report of 12 consecutive patients].

    Science.gov (United States)

    Guo, Zhao-Zhong; Liu, Xue; Li, Yan; Deng, Yan-Fang; Wang, Yang

    2007-02-01

    To evaluate the clinical applicability of Piezosurgery osteotomy: a new safe technique in managing long standing maxillary fractures. 12 patients with long-standing maxillary fractures were surgically treated using Le Fort I osteotomy. During operation, Piezosurgery osteotomy was used for bone cutting and splitting. After repositioning, the bone segments were rigidly fixed with micro Ti-plate, Ti-mesh. All the patients were followed up for 6 to 12 months, and the functional and esthetic results were evaluated. Ultrasonic microvibrations allow accurate bone cutting without oscillating injuries to the soft tissue. All the wounds healed primarily without complications. The postoperative occlusion and appearance were satisfactory. Maximal recovery of mastication and appearance can be achieved by using Piezosurgery osteotomy with fixation materials such as Ti-plates and Ti-meshes in selected patients with long-standing maxillary fractures.

  16. Sexuality educators: taking a stand by participating in research

    African Journals Online (AJOL)

    Sexuality educators: taking a stand by participating in research ... and Sexually Transmitted Infections (STIs) (United Nations Educational, Scientific, .... assimilates new ideas which could assist in keeping up with what learners need from.

  17. Litterfall and Nutrient Returns in Isolated Stands of Terminalia ...

    African Journals Online (AJOL)

    ... Stands of Terminalia catappa Trees in the Rainforest Area of Southern Nigeria. ... the adjoining rainforests produced the highest litter in the dry season months. ... Seasonal variation, Southern Nigeria, Terminalia catappa, Tropical rainforest.

  18. Free standing graphene oxide film for hydrogen peroxide sensing

    Science.gov (United States)

    Ranjan, Pranay; Balakrishnan, Jayakumar; Thakur, Ajay D.

    2018-05-01

    We report hydrogen peroxide (H2O2)sensing using free standing graphene oxide thin films prepared using a cost effective scalable approach. Such sensors may find application in pharmaceutical and food processing industries.

  19. Isopropyl alcohol tank installed at A-3 Test Stand

    Science.gov (United States)

    2009-01-01

    An isopropyl alcohol (IPA) tank is lifted into place at the A-3 Test Stand being built at NASA's John C. Stennis Space Center. Fourteen IPA, water and liquid oxygen (LOX) tanks are being installed to support the chemical steam generators to be used on the A-3 Test Stand. The IPA and LOX tanks will provide fuel for the generators. The water will allow the generators to produce steam that will be used to reduce pressure inside the stand's test cell diffuser, enabling operators to simulate altitudes up to 100,000 feet. In that way, operators can perform the tests needed on rocket engines being built to carry humans back to the moon and possibly beyond. The A-3 Test Stand is set for completion and activation in 2011.

  20. Stand-alone induction generators for small water power schemes

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, Adam [Intermediate Technology Development Group, Rugby (United Kingdom); Smith, Nigel [Smith Associates, Nottingham (United Kingdom)

    1996-04-01

    Conventional technology for isolated power generation is the synchronous generator. Using stand-alone induction generators has proved to have tremendous advantages in remote regions of developing countries, where electricity has significant social benefits. (author)

  1. Basic Stand Alone Medicare DME Line Items PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Durable Medical Equipment (DME) Line Items Public Use Files (PUF) with information from Medicare DME claims. The...

  2. Validation of Standing Wave Liner Impedance Measurement Method, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Hersh Acoustical Engineering, Inc. proposes to establish the feasibility and practicality of using the Standing Wave Method (SWM) to measure the impedance of...

  3. Basic Stand Alone Skilled Nursing Facility Beneficiary PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Skilled Nursing Facility (SNF) Beneficiary Public Use Files (PUF) with information from Medicare SNF claims. The...

  4. Robot-supported assessment of balance in standing and walking

    NARCIS (Netherlands)

    Shirota, Camila; van Asseldonk, Edwin; Matjacic, Zlatko; Vallery, H.; Barralon, Pierre; Maggioni, Serena; Buurke, Jaap H.; Veneman, Jan F.

    2017-01-01

    Clinically useful and efficient assessment of balance during standing and walking is especially challenging in patients with neurological disorders. However, rehabilitation robots could facilitate assessment procedures and improve their clinical value. We present a short overview of balance

  5. Stationary Density Variation Produced by a Standing Plasma Wave

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens

    1977-01-01

    Measurements are presented of a stationary density modulation produced by a standing electron plasma wave. The experimental results are well explained by taking into account the ponderomotive forces on the electrons exerted by the high frequency field.......Measurements are presented of a stationary density modulation produced by a standing electron plasma wave. The experimental results are well explained by taking into account the ponderomotive forces on the electrons exerted by the high frequency field....

  6. Destroyed virgin longleaf pine stand lives-on digitally

    Science.gov (United States)

    John C. Gilbert; S. Kush; Rebecca J. Barlow

    2015-01-01

    The Flomaton Natural Area (FNA) once stood as one of the few remnant fragments of virgin, old-growth longleaf pine stands (Pinus palustris Mill.) in the Southeast. This 80-acre stand contained trees over 200 years old. A restoration effort began in 1994 to remove off-site trees and to reintroduce fire to the site after over 40 years of fire suppression. A geographic...

  7. Do Pine Trees in Aspen Stands Increase Bird Diversity

    OpenAIRE

    Rumble, Mark A; Mills, Todd R; Dystra, Brian L; Flake, Lester D

    2001-01-01

    In the Black Hills of South Dakota, quaking aspen (Populus tremuloides) is being replaced by conifers through fire suppression and successional processes. Al- though the Black Hills National forest is removing conifers (primarily ponderosa pine [Pinus ponderosa])toincreasetheaspencommunitiesinsomemixedstands,ForestPlan guidelines allow four conifers per hectare to remain to increase diversity in the remaining aspen stand. We compared bird species richness in pure ponderosa pine, mixed stands ...

  8. Normal distribution of standing balance for healthy Danish children

    DEFF Research Database (Denmark)

    Pedersen, Line Kjeldgaard; Ghasemi, Habib; Rahbek, Ole

    2013-01-01

    Title: Normal distribution of standing balance for healthy Danish children – Reproducibility of parameters of balance. Authors Line Kjeldgaard Pedersen Habib Ghasemi Ole Rahbek Bjarne Møller-Madsen 1800 characters incl. spaces Background Pedobarographic measurements are increasingly used in child......Title: Normal distribution of standing balance for healthy Danish children – Reproducibility of parameters of balance. Authors Line Kjeldgaard Pedersen Habib Ghasemi Ole Rahbek Bjarne Møller-Madsen 1800 characters incl. spaces Background Pedobarographic measurements are increasingly used...

  9. J-2 Engine ready to go into test stand

    Science.gov (United States)

    1965-01-01

    Two technicians watch carefully as cables prepare to lift a J-2 engine into a test stand. The J-2 powered the second stage and the third stage of the Saturn V moon rocket. The towering 363-foot Saturn V was a multi-stage, multi-engine launch vehicle standing taller than the Statue of Liberty. Altogether, the Saturn V engines produced as much power as 85 Hoover Dams.

  10. Standing Wave Field Distribution in Graded-Index Antireflection Coatings

    Directory of Open Access Journals (Sweden)

    Hongxiang Deng

    2018-01-01

    Full Text Available Standing wave field distributions in three classic types of graded-index antireflection coatings are studied. These graded-index antireflection coatings are designed at wavelengths from 200 nm to 1200 nm, which is the working wavelength range of high energy laser system for inertial-fusion research. The standing wave field distributions in these coatings are obtained by the numerical calculation of electromagnetic wave equation. We find that standing wave field distributions in these three graded-index anti-reflection coatings are quite different. For the coating with linear index distribution, intensity of standing wave field decreases periodically from surface to substrate with narrow oscillation range and the period is proportional to the incident wavelength. For the coating with exponential index distribution, intensity of standing wave field decreases periodically from surface to substrate with large oscillation range and the period is also proportional to the incident wavelength. Finally, for the coating with polynomial index, intensity of standing wave field is quickly falling down from surface to substrate without an obvious oscillation. We find that the intensity of standing wave field in the interface between coating and substrate for linear index, exponential index and polynomial index are about 0.7, 0.9 and 0.7, respectively. Our results indicate that the distributions of standing wave field in linear index coating and polynomial index coating are better than that in exponential index coating for the application in high energy laser system. Moreover, we find that the transmittance of linear index coating and polynomial index coating are also better than exponential index coating at the designed wavelength range. Present simulation results are useful for the design and application of graded-index antireflection coating in high energy laser system.

  11. Modeling Coast Redwood Variable Retention Management Regimes

    Science.gov (United States)

    John-Pascal Berrill; Kevin O' Hara

    2007-01-01

    Variable retention is a flexible silvicultural system that provides forest managers with an alternative to clearcutting. While much of the standing volume is removed in one harvesting operation, residual stems are retained to provide structural complexity and wildlife habitat functions, or to accrue volume before removal during subsequent stand entries. The residual...

  12. The long-term hydrological effect of forest stands on the stability of slopes

    Science.gov (United States)

    Bogaard, T. A.; Meng, W.; van Beek, L. P. H.

    2012-04-01

    used in a spatially distributed, physical-based, dynamical model to simulate the hydrology and resulting stability for a catchment on a daily scale. The results can be used to identify end members of the hydrological influence of forests on slope stability and the typical variations in stability associated with the various growth stages. They indicate that the influence of forest stand age on the water consumption can be significant and has clear consequences for the antecedent soil moisture condition within a slope and thus on the potential for slope destabilization. The outcome should help to understand the long-term impact of vegetation on slope hydrology and define sustainable and reliable management strategies at the scale of forest stands. Keywords: slope stability, hydrology, vegetation, long-tem effect

  13. Species Diversity of Oak Stands and Its Significance for Drought Resistance

    Directory of Open Access Journals (Sweden)

    Jan Kotlarz

    2018-03-01

    Full Text Available Drought periods have an adverse impact on the condition of oak stands. Research on different types of ecosystems has confirmed a correlation between plant species diversity and the adverse effects of droughts. The purpose of this study was to investigate the changes that occurred in an oak stand (Krotoszyn Plateau, Poland under the impact of the summer drought in 2015. We used a method based on remote sensing indices from satellite images in order to detect changes in the vegetation in 2014 and 2015. A positive difference was interpreted as an improvement, whereas a negative one was treated as a deterioration of the stand condition. The Shannon-Wiener species diversity was estimated using an iterative principal component analysis (PCA algorithm based on aerial images. We observed a relationship between the species indices of the individual forest divisions and their response to drought. The highest correlation between the index differences and the Shannon-Wiener indices was found for the Green Normalized Difference Vegetation Index (GNDVI index (+0.74. In addition, correlations were observed between the mean index difference and the percentage shares in the forest divisions of species such as Pinus sylvestris L. (P. sylvestris (+0.67 ± 0.08 and Quercus robur L. (Q. robur (−0.65 ± 0.10. Our results lead us to infer that forest management based on highly diverse habitats is more suitable to meet the challenges in the context of global climatic changes, characterized by increasingly frequent droughts.

  14. Construction, commissioning and initial operation of 2400W refrigerator and cold test stand for CDM testing

    International Nuclear Information System (INIS)

    Dubbs, J.D.; Kreinbrink, K.

    1994-01-01

    Air Products and CVI collaborated to design, construct and commission a refrigerator, test stands and integrated control system for the General Dynamics Collider Dipole Magnet Cold Test Facility (CTF) in Hammond, LA. The original project schedule required the cold test facility to be operational within 17 months of the notice to proceed. Midway through the project, changes in General Dynamics magnet testing requirements necessitated doubling the plant capacity, but the on stream date for the initial capacity increment could not be relaxed. The Air Products/CVI team had to adapt the project execution strategy to mitigate the schedule impact of the expansion in a cost effective manner without impacting system functionality, quality or safety. An equally challenging aspect of the job was that the (CTF) was being designed while several major systems that would interface with the CTF were being engineered. General Dynamics, Air Products and CVI had to work very closely to manage the interface issues. The teams efforts were very successful. The Hammond refrigerator/liquifier was started up on schedule. The first two test stands are currently being commissioned and will be on stream just six weeks later than the pre-expansion schedule target and all four test stands will be operational in time to support General Dynamics magnet testing requirements

  15. Identification of varieties and gene flow in Douglas fir exemplified in artificially established stands in Germany

    Directory of Open Access Journals (Sweden)

    Barbara Fussi

    2013-12-01

    Full Text Available Douglas-fir [Pseudotsuga menziesii (Mirb. Franco] is an economically valuable non-native tree species in Germany and is considered very promising in view of global climate change. Therefore, the genetic characterization of Douglas-fir populations and seed stands in Germany is essential. We studied coastal and interior Douglas-fir varieties, both present in Germany, by using eleven isoenzyme and four microsatellite loci. By analyzing eight reference populations of known origin we were able to identify the two varieties on the population level using Bayesian and distance based methods. Seven populations present in Bavaria were then successfully assigned to one of the two varieties. Within varieties we found stronger grouping within the interior variety than within the coastal one. Despite lower differences within coastal Douglas-fir we have first indications for the origin of two populations. For two Bavarian populations, natural regeneration was included and genetic data revealed no significant genetic difference between adults and offspring. The parentage analysis for one of the studied stands revealed that a large proportion of adults took part in the reproduction, but some trees were more successful than others in transferring their genes to the next generation. Our study was able to improve variety identification of Douglas-fir using isoenzyme markers and nuclear microsatellites and study reproductive patterns, both are important issues for the management of Douglas-fir stands in Bavaria.

  16. Scaling Hydrologic Processes in Boreal Forest Stands: New Eco-hydrological Perspectives or Deja vu?

    Science.gov (United States)

    Silins, U.; Lieffers, V. J.; Landhausser, S. M.; Mendoza, C. A.; Devito, K. J.; Petrone, R. M.; Gan, T. Y.

    2006-12-01

    The leaf area of forest canopies is both main attribute of stands controlling water balance through transpiration and interception, and "engine" driving stand growth, stand dynamics, and forest succession. While transpiration and interception dynamics are classic themes in forest hydrology, we present results from our eco-hydrological research on boreal trees to highlight how more recent eco-physiological insights into species specific controls over water use and leaf area such as hydraulic architecture, cavitation, sapwood-leaf area relationships, and root system controls over water uptake are providing new insights into integrated atmospheric-autecological controls over these hydrologic processes. These results are discussed in the context of newer eco-hydrological frameworks which may serve to aid in exploring how forest disturbance and subsequent trajectories of hydrologic recovery are likely to affect both forest growth dynamics and hydrology of forested landscapes in response to forest management, severe forest pest epidemics such as the Mountain Pine Beetle epidemic in Western Canada, and climate change.

  17. Economic considerations of uneven-age hardwood management

    Science.gov (United States)

    H. Clay Smith; Gary W. Miller

    1987-01-01

    Uneven-age management or partial cutting methods as described in this paper allow foresters to manage eastern hardwood stands and harvest forest products without clearcutting. These methods can involve regular periodic harvests, at least for the short term, based on stand conditions and growing-site capabilities. We are not going to make the decision as to which is the...

  18. Mixing Effects in Norway Spruce—European Beech Stands Are Modulated by Site Quality, Stand Age and Moisture Availability

    Directory of Open Access Journals (Sweden)

    Léa Houpert

    2018-02-01

    Full Text Available Although mixing tree species is considered an efficient risk-reduction strategy in the face of climate change, the conditions where mixtures are more productive than monocultures are under ongoing debate. Generalizations have been difficult because of the variety of methods used and due to contradictory findings regarding the effects of the species investigated, mixing proportions, and many site and stand conditions. Using data from 960 plots of the Swiss National Forest Inventory data, we assessed whether Picea abies (L. Karst–Fagus sylvatica L. mixed stands are more productive than pure stands, and whether the mixing effect depends on site- or stand-characteristics. The species proportions were estimated using species proportion by area, which depends on the maximum stand basal area of an unmanaged stand (BAmax. Four different alternatives were used to estimate BAmax and to investigate the effect of these differing alternatives on the estimated mixture effect. On average, the mixture had a negative effect on the growth of Picea abies. However, this effect decreased as moisture availability increased. Fagus sylvatica grew better in mixtures and this effect increased with site quality. A significant interaction between species proportions and quadratic mean diameter, a proxy for stand age, was found for both species: the older the stand, the better the growth of Fagus sylvatica and the lower the growth of Picea abies. Overyielding was predicted for 80% of the investigated sites. The alternative to estimate BAmax weakly modulated the estimated mixture effect, but it did not affect the way mixing effects changed with site characteristics.

  19. The influence of sampling unit size and spatial arrangement patterns on neighborhood-based spatial structure analyses of forest stands

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H.; Zhang, G.; Hui, G.; Li, Y.; Hu, Y.; Zhao, Z.

    2016-07-01

    Aim of study: Neighborhood-based stand spatial structure parameters can quantify and characterize forest spatial structure effectively. How these neighborhood-based structure parameters are influenced by the selection of different numbers of nearest-neighbor trees is unclear, and there is some disagreement in the literature regarding the appropriate number of nearest-neighbor trees to sample around reference trees. Understanding how to efficiently characterize forest structure is critical for forest management. Area of study: Multi-species uneven-aged forests of Northern China. Material and methods: We simulated stands with different spatial structural characteristics and systematically compared their structure parameters when two to eight neighboring trees were selected. Main results: Results showed that values of uniform angle index calculated in the same stand were different with different sizes of structure unit. When tree species and sizes were completely randomly interspersed, different numbers of neighbors had little influence on mingling and dominance indices. Changes of mingling or dominance indices caused by different numbers of neighbors occurred when the tree species or size classes were not randomly interspersed and their changing characteristics can be detected according to the spatial arrangement patterns of tree species and sizes. Research highlights: The number of neighboring trees selected for analyzing stand spatial structure parameters should be fixed. We proposed that the four-tree structure unit is the best compromise between sampling accuracy and costs for practical forest management. (Author)

  20. The role of forest stand density in controlling soil erosion: implications to sediment-related disasters in Japan.

    Science.gov (United States)

    Razafindrabe, Bam H N; He, Bin; Inoue, Shoji; Ezaki, Tsugio; Shaw, Rajib

    2010-01-01

    The role of forest stand density in controlling soil erosion was investigated in Ehime Prefecture, Japan. The main objective was to compare soil erosion under different forest conditions including forest type, species composition, and stand density as influenced by thinning operations. Relative yield index (Ry) was used as an indicator of stand density to reflect the degree of management operations in the watershed. Eleven treatments were established based on the above forest conditions. Soil loss was collected in each of the 11 treatments after each rainfall event for a period of 1 year. The paper presents summary data on soil loss as affected by forest conditions and rainfall patterns. Findings showed that an appropriate forest management operation, which can be insured by stand density control, is needed to reduce soil loss. The present study plays an important role in clarifying technical processes related to soil erosion, while it helps linking these elements to current Japanese forestry issues and bringing new inputs to reducing sediment-related disasters in Japan.

  1. Windthrow Dynamics in Boreal Ontario: A Simulation of the Vulnerability of Several Stand Types across a Range of Wind Speeds

    Directory of Open Access Journals (Sweden)

    Kenneth A. Anyomi

    2017-06-01

    Full Text Available In Boreal North America, management approaches inspired by the variability in natural disturbances are expected to produce more resilient forests. Wind storms are recurrent within Boreal Ontario. The objective of this study was to simulate wind damage for common Boreal forest types for regular as well as extreme wind speeds. The ForestGALES_BC windthrow prediction model was used for these simulations. Input tree-level data were derived from permanent sample plot (PSP data provided by the Ontario Ministry of Natural Resources. PSPs were assigned to one of nine stand types: Balsam fir-, Jack pine-, Black spruce-, and hardwood-dominated stands, and, Jack pine-, spruce-, conifer-, hardwood-, and Red and White pine-mixed species stands. Morphological and biomechanical parameters for the major tree species were obtained from the literature. At 5 m/s, predicted windthrow ranged from 0 to 20%, with damage increasing to 2 to 90% for winds of 20 m/s and to 10 to 100% for winds of 40 m/s. Windthrow varied by forest stand type, with lower vulnerability within hardwoods. This is the first study to provide such broad simulations of windthrow vulnerability data for Boreal North America, and we believe this will benefit policy decisions regarding risk management and forest planning.

  2. NASA Standing Review Board Handbook: Revision B

    Science.gov (United States)

    Amer, Tahani R.; Ortiz, James N.; Calloway, Michelle A.; Greathouse, Richard M.; Polen, Charles A.; Baker, Ronald L.; Borchardt, Heidemarie E.; Chromik, Christopher C.; Moran, Erin; Paraska, Michael W.; hide

    2016-01-01

    This SRB Handbook provides review guidance for the program and project communities and for the SRBs regarding the expectations, processes, products, timelines, and working interfaces with review organizations, Centers, Mission Directorates, Mission Support Organizations, and Management Councils. It provides guidelines for membership selection, review implementation, review products, and reporting of results. The SRB Handbook guidance may be tailored, with the Convening Authorities' approval, to meet the needs of the Agency, Mission Directorates, Centers, and the programs and projects being reviewed. The final review agreement of the SRB, program and project, and Convening Authorities for program and project Life-Cycle Reviews (LCRs) is documented in the terms of reference, as described in Section 4.1 and Appendix H.

  3. Identification of Standing Pressure Waves Sources in Primary Loops of NPP with WWER and PWR

    Directory of Open Access Journals (Sweden)

    K.N. Proskuriakov

    2016-05-01

    Full Text Available Results of measurement and calculation of Eigen frequencies of coolant pressure oscillations in primary loops of NPP are presented. The simple calculation model based on equivalence of electric circuit with elastic wave propagation in liquids and gases, which gives a sensible interpretation of standing pressure waves sources is developed. It is shown, that pressurizer manifest itself as managed Helmholtz resonator generating a number of SPW (with Eigen frequencies of steam volume, water volume and their combination with coolant volume of respiratory line.

  4. Human Research Program Space Radiation Standing Review Panel (SRP)

    Science.gov (United States)

    Woloschak, Gayle; Steinberg-Wright, S.; Coleman, Norman; Grdina, David; Hill, Colin; Iliakis, George; Metting, Noelle; Meyers, Christina

    2010-01-01

    The Space Radiation Standing Review Panel (SRP) met at the NASA Johnson Space Center (JSC) on December 9-11, 2009 to discuss the areas of current and future research targeted by the Space Radiation Program Element (SRPE) of the Human Research Program (HRP). Using evidence-based knowledge as a background for identified risks to astronaut health and performance, NASA had identified gaps in knowledge to address those risks. Ongoing and proposed tasks were presented to address the gaps. The charge to the Space Radiation SRP was to review the gaps, evaluate whether the tasks addressed these gaps and to make recommendations to NASA s HRP Science Management Office regarding the SRP's review. The SRP was requested to evaluate the practicality of the proposed efforts in light of the demands placed on the HRP. Several presentations were made to the SRP during the site visit and the SRP spent sufficient time to address the SRP charge. The SRP made a final debriefing to the HRP Program Scientist, Dr. John B. Charles, on December 11, 2009. The SRP noted that current SRPE strategy is properly science-based and views this as the best assurance of the likelihood that answers to the questions posed as gaps in knowledge can be found, that the uncertainty in risk estimates can be reduced, and that a solid, cost-effective approach to risk reduction solutions is being developed. The current approach of the SRPE, based on the use of carefully focused research solicitations, requiring thorough peer-review and approaches demonstrated to be on the path to answering the NASA strategic questions, addressed to a broad extramural community of qualified scientists, optimally positioned to take advantage of serendipitous discoveries and to leverage scientific advances made elsewhere, is sound and appropriate. The SRP viewed with concern statements by HRP implying that the only science legitimately deserving support should be "applied" or, in some instances that the very term "research" might be

  5. Acoustic radiation force on a sphere in standing and quasi-standing zero-order Bessel beam tweezers

    International Nuclear Information System (INIS)

    Mitri, F.G.

    2008-01-01

    Starting from the exact acoustic scattering from a sphere immersed in an ideal fluid and centered along the propagation axis of a standing or quasi-standing zero-order Bessel beam, explicit partial-wave representations for the radiation force are derived. A standing or a quasi-standing acoustic field is the result of propagating two equal or unequal amplitude zero-order Bessel beams, respectively, along the same axis but in opposite sense. The Bessel beam is characterized by the half-cone angle β of its plane wave components, such that β = 0 represents a plane wave. It is assumed here that the half-cone angle β for each of the counter-propagating acoustic Bessel beams is equal. Fluid, elastic and viscoelastic spheres immersed in water are treated as examples. Results indicate the capability of manipulating spherical targets based on their mechanical and acoustical properties. This condition provides an impetus for further designing acoustic tweezers operating with standing or quasi-standing Bessel acoustic waves. Potential applications include particle manipulation in micro-fluidic lab-on-chips as well as in reduced gravity environments

  6. 2015 Space Radiation Standing Review Panel

    Science.gov (United States)

    Steinberg, Susan

    2015-01-01

    The 2015 Space Radiation Standing Review Panel (from here on referred to as the SRP) met for a site visit in Houston, TX on December 8 - 9, 2015. The SRP met with representatives from the Space Radiation Element and members of the Human Research Program (HRP) to review the updated research plan for the Risk of Radiation Carcinogenesis Cancer Risk. The SRP also reviewed the newly revised Evidence Reports for the Risk of Acute Radiation Syndromes Due to Solar Particle Events (SPEs) (Acute Risk), the Risk of Acute (In-flight) and Late Central Nervous System Effects from Radiation Exposure (CNS Risk), and the Risk of Cardiovascular Disease and Other Degenerative Tissue Effects from Radiation (Degen Risk), as well as a status update on these Risks. The SRP would like to commend Dr. Simonsen, Dr. Huff, Dr. Nelson, and Dr. Patel for their detailed presentations. The Space Radiation Element did a great job presenting a very large volume of material. The SRP considers it to be a strong program that is well-organized, well-coordinated and generates valuable data. The SRP commended the tissue sharing protocols, working groups, systems biology analysis, and standardization of models. In several of the discussed areas the SRP suggested improvements of the research plans in the future. These include the following: It is important that the team has expanded efforts examining immunology and inflammation as important components of the space radiation biological response. This is an overarching and important focus that is likely to apply to all aspects of the program including acute, CVD, CNS, cancer and others. Given that the area of immunology/inflammation is highly complex (and especially so as it relates to radiation), it warrants the expansion of investigators expertise in immunology and inflammation to work with the individual research projects and also the NASA Specialized Center of Research (NSCORs). Historical data on radiation injury to be entered into the Watson

  7. Feedbacks of windthrow for Norway spruce and Scots pine stands under changing climate

    International Nuclear Information System (INIS)

    Panferov, O; Rauch, E; Doering, C; Ahrends, B; Sogachev, A

    2009-01-01

    Wind damage is one of the major natural disturbances that can occur worldwide in most types of forests. Enhanced management using adequate decision support systems (DSS) can considerably reduce the risk of windthrow. The decision support system 'Forest and Climate Change' (DSS-WuK) which is currently being developed at Goettingen University aims at providing a tool for the quantitative assessment of biotic and abiotic risks for forest ecosystems under the conditions of changing climate. In order to assess the future risks of wind damage the system employs a coupled modelling approach combining the turbulence model SCAlar DIStribution (SCADIS) with the soil-vegetation-atmosphere-transfer (SVAT) model BROOK 90. The present study investigates projections of wind damage in Solling, Germany under climate scenarios A1B and B1, taking into account the windthrow feedbacks-changes of microclimate as a result of tree fall and consequent stabilization or destabilization of a forest stand. The results of the study indicate that in Solling the risk of windthrow for spruce and pine forest stands is likely to increase considerably during the 21st century. The general tendencies indicate that under A1B the probability of damage would be higher than under B1 and that under the same climate and soil conditions the risk for spruce stands would be higher than for pine stands of equal age. The degree of damage and feedback contribution as well as a sign of feedback in each particular case will strongly depend on the particular local or regional combination of climatic and soil factors with tree species, age and structure. For Solling the positive feedback to local climatic forcing is found. The feedback contributes considerably (up to 6% under given conditions) to the projected forest damage and cannot be neglected. Therefore, the adequate projection of future damage probabilities can be performed only with a process-based coupled soil-atmosphere model with corresponding high spatial

  8. Soil fauna as an indicator of soil quality in forest stands, pasture and secondary forest

    Directory of Open Access Journals (Sweden)

    Felipe Vieira da Cunha Neto

    2012-11-01

    Full Text Available The interactions between soil invertebrates and environmental variations are relatively unknown in the assessment of soil quality. The objective of this study was to evaluate soil quality in areas with different soil management systems, based on soil fauna as indicator, in Além Paraíba, Minas Gerais, Brazil. The soil invertebrate community was sampled using pitfall traps, in the dry and rainy seasons, from areas with five vegetation types (acacia, mimosa, eucalyptus, pasture, and secondary forest. The abundance of organisms and the total and average richness, Shannon's diversity index, the Pielou uniformity index, and change index V were determined. The fauna was most abundant in the areas of secondary forest and mimosa plantations in the dry season (111.3 and 31.7 individuals per trap per day, respectively. In the rainy season, the abundance of organisms in the three vegetation types did not differ. The highest values of average and total richness were recorded in the secondary forest in the dry season and in the mimosa stand in the rainy season. Shannon's index ranged from 1.57 in areas with acacia and eucalyptus in the rainy season to 3.19 in the eucalyptus area in the dry season. The uniformity index was highest in forest stands (eucalyptus, acacia and mimosa in the dry season, but higher in the rainy season in the pasture and secondary forest than in the forest stands. The change index V indicated that the percentage of extremely inhibited groups was lowest in the area with mimosa, both in the dry and rainy season (36 and 23 %, respectively. Of all forest stands, the mimosa area had the most abundant soil fauna.

  9. Post-cultural stand dynamics in an abandoned chestnut coppice at its ecological border

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available Until the be­ginning of the last century, chestnut has played an important role as staple food and primary wood source. In many cases it was cultivated at the border of its ecological limits where it was planted by man in place of the original and more site-adapted tree species. However, with the abandonment of the rural activities, ma­nagement of chestnut forests was progressively left starting from more marginal areas, usually occupied by coppice stands. After the interruption of the traditional coppice management system (usual rotation periods of 10-25 years, natural intra- and interspecific competition dynamics have become the driving force of the stand evolution. This may lead to dramatic changes in both structure and species composition of the stands. The aim of this study is to analyse the post-cultural evolution of an abandoned chestnut coppice in the Pesio Valley (Piedmont, Italy in order to highlight the competition among different "basic silvi­cultural components" of the forest using a dendroecological approach. The "basic silvicultural components" are intended as the elements defined as groups of trees of the stand that have similar features such as silvi­culturally relevant attributes: species (chestnut, beech, fir, origin (seed, sprout and cultural age and function (standard/reserve, maiden, shoot, regeneration, dead tree. The mean growth curves of the compo­nents show the different fitness of each category. From a general point of view, the beech and fir components show a better competitive potential in comparison with chestnut. Among chestnut components, maidens from seeds reveal a better growth trend compared to coppice shoots and standards.

  10. Handbook of quality management according to the regulation DIN EN ISO/IEC 17025 for the national EU reference laboratory or air quality at the Federal Office for Environmental Protection. State of the art: September 2009; Qualitaetsmanagement-Handbuch nach DIN EN ISO/IEC 17025 fuer das Nationale EU-Referenzlabor fuer Luftqualitaet im Umweltbundesamt. Stand September 2009

    Energy Technology Data Exchange (ETDEWEB)

    Medem, Anneliese (comp.)

    2010-01-15

    The past quality management manual of the national EU reference laboratory for air quality completely was revised. The new quality management manual under consideration contains a determination of the following aspects: Organisation of construction processing, fundamental regulations of the management system concerning to quality, statements to the quality politics, paramount goals. The presented quality management system is regarded to all elements of the regulation DIN EN ISO/IEC 17025:2005 with consideration of the special requirements of the national European Union reference laboratory for air quality in the Federal Office for Environment Protection (Dessau-Rosslau, Federal Republic of Germany).

  11. Quantifying climate-growth relationships at the stand level in a mature mixed-species conifer forest.

    Science.gov (United States)

    Teets, Aaron; Fraver, Shawn; Weiskittel, Aaron R; Hollinger, David Y

    2018-03-11

    A range of environmental factors regulate tree growth; however, climate is generally thought to most strongly influence year-to-year variability in growth. Numerous dendrochronological (tree-ring) studies have identified climate factors that influence year-to-year variability in growth for given tree species and location. However, traditional dendrochronology methods have limitations that prevent them from adequately assessing stand-level (as opposed to species-level) growth. We argue that stand-level growth analyses provide a more meaningful assessment of forest response to climate fluctuations, as well as the management options that may be employed to sustain forest productivity. Working in a mature, mixed-species stand at the Howland Research Forest of central Maine, USA, we used two alternatives to traditional dendrochronological analyses by (1) selecting trees for coring using a stratified (by size and species), random sampling method that ensures a representative sample of the stand, and (2) converting ring widths to biomass increments, which once summed, produced a representation of stand-level growth, while maintaining species identities or canopy position if needed. We then tested the relative influence of seasonal climate variables on year-to-year variability in the biomass increment using generalized least squares regression, while accounting for temporal autocorrelation. Our results indicate that stand-level growth responded most strongly to previous summer and current spring climate variables, resulting from a combination of individualistic climate responses occurring at the species- and canopy-position level. Our climate models were better fit to stand-level biomass increment than to species-level or canopy-position summaries. The relative growth responses (i.e., percent change) predicted from the most influential climate variables indicate stand-level growth varies less from to year-to-year than species-level or canopy-position growth responses. By

  12. Multi-Cohort Stand Structural Classification: Ground- and LiDAR-based Approaches for Boreal Mixedwood and Black Spruce Forest Types of Northeastern Ontario

    Science.gov (United States)

    Kuttner, Benjamin George

    Natural fire return intervals are relatively long in eastern Canadian boreal forests and often allow for the development of stands with multiple, successive cohorts of trees. Multi-cohort forest management (MCM) provides a strategy to maintain such multi-cohort stands that focuses on three broad phases of increasingly complex, post-fire stand development, termed "cohorts", and recommends different silvicultural approaches be applied to emulate different cohort types. Previous research on structural cohort typing has relied upon primarily subjective classification methods; in this thesis, I develop more comprehensive and objective methods for three common boreal mixedwood and black spruce forest types in northeastern Ontario. Additionally, I examine relationships between cohort types and stand age, productivity, and disturbance history and the utility of airborne LiDAR to retrieve ground-based classifications and to extend structural cohort typing from plot- to stand-levels. In both mixedwood and black spruce forest types, stand age and age-related deadwood features varied systematically with cohort classes in support of an age-based interpretation of increasing cohort complexity. However, correlations of stand age with cohort classes were surprisingly weak. Differences in site productivity had a significant effect on the accrual of increasingly complex multi-cohort stand structure in both forest types, especially in black spruce stands. The effects of past harvesting in predictive models of class membership were only significant when considered in isolation of age. As an age-emulation strategy, the three cohort model appeared to be poorly suited to black spruce forests where the accrual of structural complexity appeared to be more a function of site productivity than age. Airborne LiDAR data appear to be particularly useful in recovering plot-based cohort types and extending them to the stand-level. The main gradients of structural variability detected using Li

  13. Stand diameter distribution modelling and prediction based on Richards function.

    Directory of Open Access Journals (Sweden)

    Ai-guo Duan

    Full Text Available The objective of this study was to introduce application of the Richards equation on modelling and prediction of stand diameter distribution. The long-term repeated measurement data sets, consisted of 309 diameter frequency distributions from Chinese fir (Cunninghamia lanceolata plantations in the southern China, were used. Also, 150 stands were used as fitting data, the other 159 stands were used for testing. Nonlinear regression method (NRM or maximum likelihood estimates method (MLEM were applied to estimate the parameters of models, and the parameter prediction method (PPM and parameter recovery method (PRM were used to predict the diameter distributions of unknown stands. Four main conclusions were obtained: (1 R distribution presented a more accurate simulation than three-parametric Weibull function; (2 the parameters p, q and r of R distribution proved to be its scale, location and shape parameters, and have a deep relationship with stand characteristics, which means the parameters of R distribution have good theoretical interpretation; (3 the ordinate of inflection point of R distribution has significant relativity with its skewness and kurtosis, and the fitted main distribution range for the cumulative diameter distribution of Chinese fir plantations was 0.4∼0.6; (4 the goodness-of-fit test showed diameter distributions of unknown stands can be well estimated by applying R distribution based on PRM or the combination of PPM and PRM under the condition that only quadratic mean DBH or plus stand age are known, and the non-rejection rates were near 80%, which are higher than the 72.33% non-rejection rate of three-parametric Weibull function based on the combination of PPM and PRM.

  14. Self Managing the Consequences of Major Limb Trauma

    National Research Council Canada - National Science Library

    MacKenzie, Ellen J

    2008-01-01

    .... The intervention will build on widely accepted self-management programs developed for persons with arthritis as well as components of a face-to-face self-management program for civilians with long-standing limb loss...

  15. Networked business process management

    NARCIS (Netherlands)

    Grefen, P.W.P.J.

    2013-01-01

    In the current economy, a shift can be seen from stand-alone business organizations to networks of tightly collaborating business organizations. To allow this tight collaboration, business process management in these collaborative networks is becoming increasingly important. This paper discusses

  16. STANDING CONCERTATION COMMITTEE OCTOBER 1999 ORDINARY MEETING

    CERN Document Server

    1999-01-01

    Original: FrenchThe meeting was mainly devoted to the examination of the items below, to which the Committee had allocated two meetings:Preparation for the meeting of TREF on 19 November 1999The SCC took note of the agenda for that meeting which includes additional information on the long-term care insurance project, a second report on staff recruitment and retention, a status report on the voluntary programmes (especially an assessment of the Progressive Retirement Programme), a proposal for the application of the cost-of-living index for 2000, an addendum to the technical amendments to be made to the Staff Rules and Regulations, a balance sheet of CERN's apprenticeship programmes and a status report with regard to guarantees for the pensions of members of the personnel in the event of the dissolution of the Organization.Long-term care: TREF would be given further information following the comments made when the Management's initial proposals were presented to the Forum at its September meeting. The informat...

  17. Multiple sclerosis in Kashmir: Where we stand.

    Science.gov (United States)

    Zahoor, Insha; Haq, Ehtishamul; Asimi, Ravouf

    2017-02-15

    Multiple sclerosis (MS) is a disabling neurological disorder commonly diagnosed in young adults. Its causes still remain inexplicable and presently it can only be managed by different drug treatments. There has been a remarkable shift in MS perspective across world. One of its peculiar attribute is unstable (changing) prevalence rate across different parts of the world. Earlier MS was believed to be less prevalent in India, however, there has been growing evidence suggesting its increasing prevalence which has changed its perspective from being less prevalent to more prevalent. There is a complete lack of data on the prevalence rate and epidemiological basis of MS in Kashmir Valley of India. By and large MS research in this region seems to be hampered due to lack of proper research infrastructure, absence of MS registry, inadequate funding and more importantly by absence of active local and foreign collaborations between scientists and clinicians. This review tries to raise some key issues encountered while conducting MS research in Kashmir and at the same time highlighting the measures to be adopted for carrying out a large scale molecular epidemiological study. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Standing wave acoustic levitation on an annular plate

    Science.gov (United States)

    Kandemir, Mehmet Hakan; Çalışkan, Mehmet

    2016-11-01

    In standing wave acoustic levitation technique, a standing wave is formed between a source and a reflector. Particles can be attracted towards pressure nodes in standing waves owing to a spring action through which particles can be suspended in air. This operation can be performed on continuous structures as well as in several numbers of axes. In this study an annular acoustic levitation arrangement is introduced. Design features of the arrangement are discussed in detail. Bending modes of the annular plate, known as the most efficient sound generation mechanism in such structures, are focused on. Several types of bending modes of the plate are simulated and evaluated by computer simulations. Waveguides are designed to amplify waves coming from sources of excitation, that are, transducers. With the right positioning of the reflector plate, standing waves are formed in the space between the annular vibrating plate and the reflector plate. Radiation forces are also predicted. It is demonstrated that small particles can be suspended in air at pressure nodes of the standing wave corresponding to a particular bending mode.

  19. Relating P-band AIRSAR backscatter to forest stand parameters

    Science.gov (United States)

    Wang, Yong; Melack, John M.; Davis, Frank W.; Kasischke, Eric S.; Christensen, Norman L., Jr.

    1993-01-01

    As part of research on forest ecosystems, the Jet Propulsion Laboratory (JPL) and collaborating research teams have conducted multi-season airborne synthetic aperture radar (AIRSAR) experiments in three forest ecosystems including temperate pine forest (Duke, Forest, North Carolina), boreal forest (Bonanza Creek Experimental Forest, Alaska), and northern mixed hardwood-conifer forest (Michigan Biological Station, Michigan). The major research goals were to improve understanding of the relationships between radar backscatter and phenological variables (e.g. stand density, tree size, etc.), to improve radar backscatter models of tree canopy properties, and to develop a radar-based scheme for monitoring forest phenological changes. In September 1989, AIRSAR backscatter data were acquired over the Duke Forest. As the aboveground biomass of the loblolly pine forest stands at Duke Forest increased, the SAR backscatter at C-, L-, and P-bands increased and saturated at different biomass levels for the C-band, L-band, and P-band data. We only use the P-band backscatter data and ground measurements here to study the relationships between the backscatter and stand density, the backscatter and mean trunk dbh (diameter at breast height) of trees in the stands, and the backscatter and stand basal area.

  20. A Measurement System of Electric Signals on Standing Trees

    Directory of Open Access Journals (Sweden)

    Hao TIAN

    2014-01-01

    Full Text Available The standing tree electric signal (STES, defined as the electric potential difference between standing trees and the surrounding soil, can be utilized to reflect the biological nature of the trees. This signal should be measured precisely because it can also be collected and used as the electric power energy. In this paper, the automatic measurement system of standing tree biological electric signal based on MSP430 MCU. First of all, the basic structure of the presented system is introduced and it includes three modules: amplification module of the standing tree electric signal, the acquisition and processing of the signal module and the serial communication module. Then, the performances of the built system are respectively validated by the Poplar, Planetree, and Platanus in Beijing Forestry University. The result indicated that the relative error of this system is less than 2 %. The presented system can be considered as the foundation of the subsequent study on the mechanism of the biological electric signal and the application of the biological electric energy on standing trees.

  1. Labelling : Security in Information Management and Sharing

    NARCIS (Netherlands)

    Schotanus, H.A.; Hartog, T.; Hut, D.H.; Boonstra, D.

    2011-01-01

    Military communication infrastructures are often deployed as stand-alone information systems operating at the System High mode. Network-Enabled Capabilities (NEC) and combined military operations lead to new requirements for information management and sharing which current communication

  2. sustainable management of rainforest in southern nigeria

    African Journals Online (AJOL)

    BARTH

    2012-07-23

    Jul 23, 2012 ... predict the stand structures of the most complex tropical rainforest ecosystem in Southern ... matrix R was 0.977, which is the intrinsic rate of natural increase with less than zero. ..... management of renewable resources with.

  3. Lithium Pharmacogenetics: Where Do We Stand?

    Science.gov (United States)

    Pisanu, Claudia; Melis, Carla; Squassina, Alessio

    2016-11-01

    Preclinical Research Bipolar disorder (BPD) is a chronic and disabling psychiatric disorder with a prevalence of 0.8-1.2% in the general population. Although lithium is considered the first-line treatment, a large percentage of patients do not respond sufficiently. Moreover, lithium can induce severe side effects and has poor tolerance and a narrow therapeutic index. The genetics of lithium response has been largely investigated, but findings have so far failed to identify reliable biomarkers to predict clinical response. This has been largely determined by the highly complex phenotipic and genetic architecture of lithium response. To this regard, collaborative initiatives hold the promise to provide robust and standardized methods to disantenagle this complexity, as well as the capacity to collect large samples of patietnts, a crucial requirement to study the genetics of complex phenotypes. The International Consortium on Lithium Genetics (ConLiGen) has recently published the largest study so far on lithium response reporting significant associations for two long noncoding RNAs (lncRNAs). This result provides relevant insights into the pharmacogenetics of lithium supporting the involvement of the noncoding portion of the genome in modulating clinical response. Although a vast body of research is engaged in dissecting the genetic bases of response to lithium, the several drawbacks of lithium therapy have also stimulated multiple efforts to identify new safer treatments. A drug repurposing approach identified ebselen as a potential lithium mimetic, as it shares with lithium the ability to inhibit inositol monophosphatase. Ebselen, an antioxidant glutathione peroxidase mimetic, represents a valid and promising example of new potential therapeutic interventions for BD, but the paucity of data warrant further investigation to elucidate its potential efficacy and safety in the management of BPD. Nevertheless, findings provided by the growing field of pharmacogenomic

  4. The role of stand history in assessing forest impacts

    Science.gov (United States)

    Dale, V.H.; Doyle, T.W.

    1987-01-01

    Air pollution, harvesting practices, and natural disturbances can affect the growth of trees and forest development. To make predictions about anthropogenic impacts on forests, we need to understand how these factors affect tree growth. In this study the effect of disturbance history on tree growth and stand structure was examined by using a computer model of forest development. The model was run under the climatic conditions of east Tennessee, USA, and the results compared to stand structure and tree growth data from a yellow poplar-white oak forest. Basal area growth and forest biomass were more accurately projected when rough approximations of the thinning and fire history typical of the measured plots were included in the simulation model. Stand history can influence tree growth rates and forest structure and should be included in any attempt to assess forest impacts.

  5. Standing phase angle reduction for power system restoration

    Energy Technology Data Exchange (ETDEWEB)

    Hazarika, D. [Assam Engineering College (India). Electrical Engineering Dept.; Sinha, A.K. [IIT Khargpur (India). Electrical Engineering Dept.

    1998-01-01

    The paper describes a methodology for the reduction of standing phase angle (SPA) difference between two buses of a power system, which is essential before interconnecting a line between two buses. This problem is encountered normally during restoration operations of a power system. For this purpose, the standing phase angle difference between two specific buses is represented in terms of sensitivity factors associated with the change in real power injections at the buses. To arrive at the desired standing phase angle difference between two buses, the modified contribution at generation/load buses have been evaluated based on 'higher the sensitivity higher the participation' logic. This methodology acts as a direct help to reduce excessive SPA difference between two buses to an acceptable limit, which otherwise requires regulation of various generation levels on a trial and error basis. (author)

  6. The Missouri Ozark Forest Ecosystem Project: the effects of forest management on the forest ecosystem

    Science.gov (United States)

    Brian Brookshire; Carl Hauser

    1993-01-01

    The effects of forest management on non-timber resources are of growing concern to forest managers and the public. While many previous studies have reported effects of stand-level treatments (less than 15 ha) on various stand-level attributes, few studies have attempted to document the influence of forest management on the biotic and abiotic characteristics of entire...

  7. Stand tending and root rot in Norway spruce stands - economical effects caused by root rot at different thinning regimes

    International Nuclear Information System (INIS)

    Johansson, Mats

    1997-01-01

    This report is divided into three parts: 1) a literature study describing the most common fungi causing rot in wood and descriptions of various strategies to reduce economic loss from root rot, 2) a check of a model describing the development of butt rot in pure Norway spruce plantations in southern Sweden, and 3) simulated economic effects of root rot in stands with various stand tending. The rot model was used to estimate future rot frequencies in the economic calculations. In order to avoid overestimations of rot frequencies, the calculations were also executed when assuming slower growth of rot than shown in the model. When analysing the economical effects of rot, the following three thinning programmes were used: Program 1: thinning at the ages of 30- and 45 years. Final felling at the ages 50-, 55-, 60-, 65-, and 70 years. Program 2: thinning at the ages of 40- and 60- years. Final felling at the ages 65 and 75 years. Program 3: thinning at the ages of 30-, 40-, 55-, and 70 years. Final felling at the ages 80 and 90 years. With an interest rate of 3%, programme 2 (final felling at the age of 65 years) had the highest value at present. This result was valid when presuming butt rot in the stand as well as when presuming no butt rot in the stand. There was a small difference between the value at present in programme 1 (final felling at the age of 60 years) and in programme 3 (final felling at the age of 80 years). When presuming butt rot in the stand, the value at present in programme 3 decreased somewhat more in comparison to the value at present in programme 1. Compared to no butt rot in the stand, the optimal final felling time appeared five to ten years earlier when assuming butt rot in the stand. Stand tending programme 1 and an interest rate of 3% were used. Interest rates 2 and 4% did not indicate shorter rotation. The calculated optimal time of final felling appeared at the same stand age whether assuming rot preset or not. The results in this study

  8. Regeneration in defoliated and thinned hardwood stands of north-central West Virginia

    Science.gov (United States)

    R. M. Muzika; M. J. Twery

    1995-01-01

    Overstory species regeneration was examined in 1989, prior to gypsy moth defoliation and thinnings, on 16 stands in the West Virginia University Forest. Three stands were thinned and defoliated while five were thinned only and three were defoliated only. Five stands were neither thinned nor defoliated. Data were collected from these stands for three years subsequent to...

  9. Regenerating mixed oak stands in Pennsylvania: a quarter-century retrospective

    Science.gov (United States)

    P. J. Gould; K. C. Steiner; J. C. Finley; M. E. McDill

    2003-01-01

    The outcomes of regeneration treatments in 90 oak-dominated stands in Pennsylvania are examined 20 to 33 years after treatment. Approximately one-quarter of the stands failed to reach 50 percent stocking after at least 20 years, but most stands regenerated successfully. Red maple is the most frequently observed species in the regenerated stands, followed by oak species...

  10. The effect of a hybrid assistive limb® on sit-to-stand and standing patterns of stroke patients

    Science.gov (United States)

    Kasai, Rie; Takeda, Sunao

    2016-01-01

    [Purpose] The Hybrid Assistive Limb® (HAL®) robot suit is a powered exoskeleton that can assist a user’s lower limb movement. The purpose of this study was to assess the effectiveness of HAL® in stroke rehabilitation, focusing on the change of the sit-to-stand (STS) movement pattern and standing posture. [Subjects and Methods] Five stroke patients participated in this study. Single leg HAL® was attached to each subject’s paretic lower limb. The subjects performed STS three times both with and without HAL® use. A tri-axial accelerometer was used to assess the STS movement pattern. Forward-tilt angle (FTA) and the time required for STS were measured with and without HAL® use. Surface electromyography (EMG) of STS and standing were recorded to assess the vastus medialis muscle activities of the paretic limb. [Results] The average FTA without HAL® use was 35° and it improved to 43° with HAL® use. The time required for STS was longer for all subjects with HAL® use (without HAL® use: 3.42 s, with HAL® use: 5.11 s). The integrated EMGs of HAL® use compared to those without HAL®, were 83.6% and 66.3% for STS and standing, respectively. [Conclusion] HAL® may be effective in improving STS and standing patterns of stroke patients. PMID:27390416

  11. Standing Up for Learning: A Pilot Investigation on the Neurocognitive Benefits of Stand-Biased School Desks

    Directory of Open Access Journals (Sweden)

    Ranjana K. Mehta

    2015-12-01

    Full Text Available Standing desks have proven to be effective and viable solutions to combat sedentary behavior among children during the school day in studies around the world. However, little is known regarding the potential of such interventions on cognitive outcomes in children over time. The purpose of this pilot study was to determine the neurocognitive benefits, i.e., improvements in executive functioning and working memory, of stand-biased desks and explore any associated changes in frontal brain function. 34 freshman high school students were recruited for neurocognitive testing at two time points during the school year: (1 in the fall semester and (2 in the spring semester (after 27.57 (1.63 weeks of continued exposure. Executive function and working memory was evaluated using a computerized neurocognitive test battery, and brain activation patterns of the prefrontal cortex were obtained using functional near infrared spectroscopy. Continued utilization of the stand-biased desks was associated with significant improvements in executive function and working memory capabilities. Changes in corresponding brain activation patterns were also observed. These findings provide the first preliminary evidence on the neurocognitive benefits of standing desks, which to date have focused largely on energy expenditure. Findings obtained here can drive future research with larger samples and multiple schools, with comparison groups that may in turn implicate the importance of stand-biased desks, as simple environmental changes in classrooms, on enhancing children’s cognitive functioning that drive their cognitive development and impact educational outcomes.

  12. Bilateral Posterior Native Hip Dislocations after Fall from Standing

    Directory of Open Access Journals (Sweden)

    Jane Xiao

    2017-10-01

    Full Text Available We present a case of bilateral posterior native hip dislocations after a fall from standing. This exceedingly rare diagnosis is classically associated with younger patients whose bones are strong enough to dislocate rather than fracture in the setting of a high-momentum collision. We present an unusual case of an 88-year-old male with native hips who sustained a low-energy collision after falling from standing and was found to have bilateral posterior hip dislocations without associated pelvis or femur fractures.

  13. The 5D Standing Wave Braneworld with Real Scalar Field

    OpenAIRE

    Merab Gogberashvili; Pavle Midodashvili

    2013-01-01

    We introduce the new 5D braneworld with the real scalar field in the bulk. The model represents the brane which bounds collective oscillations of gravitational and scalar field standing waves. These waves are out of phase; that is, the energy of oscillations passes back and forth between the scalar and gravitational waves. When the amplitude of the standing waves is small, the brane width and the size of the horizon in extra space are of a same order of magnitude, and matter fields are locali...

  14. Wavelength variation of a standing wave along a vertical spring

    Science.gov (United States)

    Welsch, Dylan; Baker, Blane

    2018-03-01

    Hand-driven resonance can be observed readily in a number of mechanical systems including thin boards, rods, strings, and springs. In order to show such behavior in the vertical spring pictured in Fig. 1, a section of spring is grasped at a location about one meter from its free end and driven by small, circular motions of the hand. At driving frequencies of a few hertz, a dramatic standing wave is generated. One of the fascinating features of this particular standing wave is that its wavelength varies along the length of the spring.

  15. Electron-phonon coupling in quasi free-standing graphene

    DEFF Research Database (Denmark)

    Christian Johannsen, Jens; Ulstrup, Søren; Bianchi, Marco

    2013-01-01

    Quasi free-standing monolayer graphene can be produced by intercalating species like oxygen or hydrogen between epitaxial graphene and the substrate crystal. If the graphene is indeed decoupled from the substrate, one would expect the observation of a similar electronic dispersion and many......-body effects, irrespective of the substrate and the material used to achieve the decoupling. Here we investigate the electron-phonon coupling in two different types of quasi free-standing monolayer graphene: decoupled from SiC via hydrogen intercalation and decoupled from Ir via oxygen intercalation. Both...

  16. Data acquisition system for PLT Neutral Beam Test Stand

    International Nuclear Information System (INIS)

    Francis, J.E. Jr.; Hammons, C.E.

    1977-01-01

    The PLT Neutral Beam Test Stand at Oak Ridge National Laboratory was constructed to test and condition powerful neutral beam sources for the Princeton Large Torus experiment at Princeton Plasma Physics Laboratory. The data acquisition system for the test stand monitors the beam characteristics and power output to determine if the beam is operating at its design specifications. The high speed of the computer system is utilized to provide near-real-time analysis of experimental data. The analysis of the data is presented as numerical tabulation and graphic display

  17. A FEW CONSIDERATIONS ABOUT TRADE FAIR STANDS DESIGN

    Directory of Open Access Journals (Sweden)

    NEIDONI Nadina

    2017-05-01

    Full Text Available The paper presents some aspects related to the design of a trade fair stand, advertising a company specialized in the fabrication of corrugated fibre board packaging. The first section reviews shortly the main features of the industrial design. The second section deals with the structural conception of successful trade shows. Further, the importance of the package in the marketing matters is addressed. In this context corrugated fibreboard, as secondary or tertiary material is essential. In the final section, a comparison between two trade fair stands, representing a corrugated fibreboard company are presented.

  18. Proceedings of standing conference on health and safety in the nuclear age

    International Nuclear Information System (INIS)

    1990-01-01

    From 5 to 6 December 1989 the second meeting of the Standing Conference on Health and Safety in the Nuclear Age was held in Brussels. The subject of the meeting was informing the public on improvements in emergency preparedness and nuclear accident management. The Standing Conference was created by the Commission of the European Communities in 1986 and its goal is to convey to the European public, via the mass media, factual information on nuclear subjects of current interest. About 100 experts and representatives of the mass media, competent authorities and socio-economic organizations followed the meeting, the specific objective of which was to discuss, from the point of view of radiation protection of the public and the environment, the improvements that nuclear accident management and intervention plans have undergone in recent years. Invited contributions underlined the presently improved levels of international and Community cooperation in radiation and nuclear safety, particularly in the fields of emergency preparedness and planning, where recent years have witnessed significant developments. The conference requested the Commission to pursue its public information efforts aimed at improving the understanding that the citizens of the Community have on the potential risks and the protective measures which were implemented in the nuclear sphere

  19. Measurements of stem diameter: implications for individual- and stand-level errors.

    Science.gov (United States)

    Paul, Keryn I; Larmour, John S; Roxburgh, Stephen H; England, Jacqueline R; Davies, Micah J; Luck, Hamish D

    2017-08-01

    monitoring relatively small changes in permanent sample plots (e.g. National Forest Inventories), noting that care is required in irregular-shaped, large-single-stemmed individuals, and (ii) use of a SDG to maximise efficiency when using inventory methods to assess basal area, and hence biomass or wood volume, at the stand scale (i.e. in studies of impacts of management or site quality) where there are budgetary constraints, noting the importance of sufficient sample sizes to ensure that the population sampled represents the true population.

  20. Tree-, stand- and site-specific controls on landscape-scale patterns of transpiration

    Science.gov (United States)

    Kathrin Hassler, Sibylle; Weiler, Markus; Blume, Theresa

    2018-01-01

    Transpiration is a key process in the hydrological cycle, and a sound understanding and quantification of transpiration and its spatial variability is essential for management decisions as well as for improving the parameterisation and evaluation of hydrological and soil-vegetation-atmosphere transfer models. For individual trees, transpiration is commonly estimated by measuring sap flow. Besides evaporative demand and water availability, tree-specific characteristics such as species, size or social status control sap flow amounts of individual trees. Within forest stands, properties such as species composition, basal area or stand density additionally affect sap flow, for example via competition mechanisms. Finally, sap flow patterns might also be influenced by landscape-scale characteristics such as geology and soils, slope position or aspect because they affect water and energy availability; however, little is known about the dynamic interplay of these controls.We studied the relative importance of various tree-, stand- and site-specific characteristics with multiple linear regression models to explain the variability of sap velocity measurements in 61 beech and oak trees, located at 24 sites across a 290 km2 catchment in Luxembourg. For each of 132 consecutive days of the growing season of 2014 we modelled the daily sap velocity and derived sap flow patterns of these 61 trees, and we determined the importance of the different controls.Results indicate that a combination of mainly tree- and site-specific factors controls sap velocity patterns in the landscape, namely tree species, tree diameter, geology and aspect. For sap flow we included only the stand- and site-specific predictors in the models to ensure variable independence. Of those, geology and aspect were most important. Compared to these predictors, spatial variability of atmospheric demand and soil moisture explains only a small fraction of the variability in the daily datasets. However, the temporal

  1. A New Standing Posture Detector to Enable People with Multiple Disabilities to Control Environmental Stimulation by Changing Their Standing Posture through a Commercial Wii Balance Board

    Science.gov (United States)

    Shih, Ching-Hsiang; Shih, Ching-Tien; Chiang, Ming-Shan

    2010-01-01

    This study assessed whether two persons with multiple disabilities would be able to control environmental stimulation using body swing (changing standing posture) and a Wii Balance Board with a newly developed standing posture detection program (i.e. a new software program turns a Wii Balance Board into a precise standing posture detector). The…

  2. The distribution of lumbar intervertebral angles in upright standing and extension is related to low back pain developed during standing.

    Science.gov (United States)

    Viggiani, Daniel; Gallagher, Kaitlin M; Sehl, Michael; Callaghan, Jack P

    2017-11-01

    Lumbar lordosis measures are poorly related to clinical low back pain, however using a controlled exposure such as prolonged standing to identify pain groups may clarify this relationship. The purpose of this study was to determine the distribution of lumbar intervertebral angles in asymptomatic persons who do (pain developers) and do not (non-pain developers) develop low back pain during standing. Sagittal plane lumbar spine radiographs of eight pain developers and eight non-pain developers were taken in three poses: upright standing, full extension and full flexion. Measures of vertebral end plate orientations from L1 to S1 were taken in each pose to compute: intervertebral angles, contribution of each level to the total curve, total lordosis, ranges of motion, relative pose positioning within the range of motion, vertebral shape, and lumbar spine recurve. Measures were compared between pain groups and lumbar levels. Pain group differences in intervertebral angles and level contributions were greatest in the full extension pose, with pain developers having greater contributions from higher lumbar levels and fewer contributions from lower levels than non-pain developers. Pain group differences in intervertebral angle distributions were less pronounced in upright standing and non-existent in full flexion. No other measures differentiated pain groups. Although participants had similar gross-lumbar spine curvature characteristics, non-pain developers have more curvature at lower levels in upright standing and full extension. These differences in regional vertebral kinematics may partially be responsible for standing-induced low back pain. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Energy wood harvesting from nurse crop of spruce seeding stand; Kuusen taimikon verhopuuston korjuu energiapuuksi

    Energy Technology Data Exchange (ETDEWEB)

    Peltola, M.; Tanttu, V.

    2008-07-01

    The study focused on establishing the productivity and costs of mechanical energy wood cutting and the profitability of forest management alternatives in the harvesting of hold-overs from spruce seeding stands. The productivity in whole-tree harvesting performed using a multi-tree whole tree processing method reached 3.5 m3/E{sub 0}h with a felling cost of 26 euros/m3. The calculated cost of chainsaw harvesting using a felling-piling technique was 16 euros/m3. The average size of trees harvested from the research stand was 15 dm3. At a rate of 17.8 euros per megawatt that was paid for forest chips delivered to the plant, the net profit using mechanical harvesting method was 272 euros per hectare. The net profit using chainsaw harvesting was 464 euros per hectare. 'Net profit' is defined here as the total amount earned, taking into account forest management costs, the production cost of forest chips, the Kemera subsidies and the price paid for the chips at the place of usage. The net profit of felling the removed trees to the ground (not processing it into fuel) was minus 124 euros. A theoretical stumpage price rate was calculated for the energy harvesting alternatives by dividing the net result by the volume of trees harvested. Theoretical stumpage price was positive when the paid price per megawatt of chips delivered to the place of usage was 13 euros per megawatt-hour for mechanically harvested chips or 10 euros per megawatt-hour for chainsaw-harvested chips. In mechanical harvesting, 17 percent of the trees harvested were damaged in the harvesting process. While it is often essential for the forest owner to ensure that any forest management measures contribute to quick profitability, the forest management benefits that will become realisable assets in the future must nevertheless also be taken into account. (orig.)

  4. Comparison of Different Height–Diameter Modelling Techniques for Prediction of Site Productivity in Natural Uneven-Aged Pure Stands

    Directory of Open Access Journals (Sweden)

    Guangshuang Duan

    2018-01-01

    Full Text Available Reliable estimates of forest site productivity are a central element of forest management. The model of height-diameter relationship of dominant trees using algebraic difference approach (ADA is a commonly used method to measure site productivity of natural uneven-aged stands. However, the existing models of this method do not recognize site type or sample plot specific variability in height curves; thus, it cannot be effectively used to estimate site type or sample plot-related site productivity for natural uneven-aged stands. Two primary subject-specific approaches, ADA with dummy variable (DV (ADA + DV and ADA with combination of dummy variable and nonlinear mixed-effects modelling (CM (ADA + CM, were proposed for height–diameter modelling. Height–diameter models developed with ADA, ADA + DV and ADA + CM were compared using data from 4161 observations on 349 permanent sample plots of four major natural uneven-aged pure stands (Spruce, Korean Larch, Mongolian Oak, and White Birch in northeastern China. It was found that models developed with ADA + CM provided the best performance, followed by the models with ADA + DV, and the models developed with ADA performed the worst. Random effects at the plot level were substantial, and their inclusion greatly improved the model’s accuracy. More importantly, the models developed with ADA + CM provide an effective method for quantifying site type- and sample plot-specific forest site productivity for uneven-aged pure stands.

  5. Tree Regeneration Spatial Patterns in Ponderosa Pine Forests Following Stand-Replacing Fire: Influence of Topography and Neighbors

    Directory of Open Access Journals (Sweden)

    Justin P. Ziegler

    2017-10-01

    Full Text Available Shifting fire regimes alter forest structure assembly in ponderosa pine forests and may produce structural heterogeneity following stand-replacing fire due, in part, to fine-scale variability in growing environments. We mapped tree regeneration in eighteen plots 11 to 15 years after stand-replacing fire in Colorado and South Dakota, USA. We used point pattern analyses to examine the spatial pattern of tree locations and heights as well as the influence of tree interactions and topography on tree patterns. In these sparse, early-seral forests, we found that all species were spatially aggregated, partly attributable to the influence of (1 aspect and slope on conifers; (2 topographic position on quaking aspen; and (3 interspecific attraction between ponderosa pine and other species. Specifically, tree interactions were related to finer-scale patterns whereas topographic effects influenced coarse-scale patterns. Spatial structures of heights revealed conspecific size hierarchies with taller trees in denser neighborhoods. Topography and heterospecific tree interactions had nominal effect on tree height spatial structure. Our results demonstrate how stand-replacing fires create heterogeneous forest structures and suggest that scale-dependent, and often facilitatory, rather than competitive, processes act on regenerating trees. These early-seral processes will establish potential pathways of stand development, affecting future forest dynamics and management options.

  6. Harvesting Effects on Species Composition and Distribution of Cover Attributes in Mixed Native Warm-Season Grass Stands

    Directory of Open Access Journals (Sweden)

    Vitalis W. Temu

    2015-05-01

    Full Text Available Managing grasslands for forage and ground-nesting bird habitat requires appropriate defoliation strategies. Subsequent early-summer species composition in mixed stands of native warm-season grasses (Indiangrass (IG, Sorghastrum nutans, big bluestem (BB, Andropogon gerardii and little bluestem (LB, Schizachyrium scoparium responding to harvest intervals (treatments, 30, 40, 60, 90 or 120 d and durations (years in production was assessed. Over three years, phased May harvestings were initiated on sets of randomized plots, ≥90 cm apart, in five replications (blocks to produce one-, two- and three-year-old stands. Two weeks after harvest, the frequencies of occurrence of plant species, litter and bare ground, diagonally across each plot (line intercept, were compared. Harvest intervals did not influence proportions of dominant plant species, occurrence of major plant types or litter, but increased that of bare ground patches. Harvest duration increased the occurrence of herbaceous forbs and bare ground patches, decreased that of tall-growing forbs and litter, but without affecting that of perennial grasses, following a year with more September rainfall. Data suggest that one- or two-year full-season forage harvesting may not compromise subsequent breeding habitat for bobwhites and other ground-nesting birds in similar stands. It may take longer than a year’s rest for similar stands to recover from such changes in species composition.

  7. Step Prediction During Perturbed Standing Using Center Of Pressure Measurements

    Directory of Open Access Journals (Sweden)

    Milos R. Popovic

    2007-04-01

    Full Text Available The development of a sensor that can measure balance during quiet standing and predict stepping response in the event of perturbation has many clinically relevant applica- tions, including closed-loop control of a neuroprothesis for standing. This study investigated the feasibility of an algorithm that can predict in real-time when an able-bodied individual who is quietly standing will have to make a step to compensate for an external perturbation. Anterior and posterior perturbations were performed on 16 able-bodied subjects using a pul- ley system with a dropped weight. A linear relationship was found between the peak center of pressure (COP velocity and the peak COP displacement caused by the perturbation. This result suggests that one can predict when a person will have to make a step based on COP velocity measurements alone. Another important feature of this finding is that the peak COP velocity occurs considerably before the peak COP displacement. As a result, one can predict if a subject will have to make a step in response to a perturbation sufficiently ahead of the time when the subject is actually forced to make the step. The proposed instability detection algorithm will be implemented in a sensor system using insole sheets in shoes with minitur- ized pressure sensors by which the COPv can be continuously measured. The sensor system will be integrated in a closed-loop feedback system with a neuroprosthesis for standing in the near future.

  8. The stand-alone test and decreasing serial cost sharing

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Thorlund-Petersen, Lars

    2000-01-01

    The rule of decreasing serial cost sharing defined in de Frutos [1] over the class of concave cost functions may violate the important stand-alone test. Sufficient conditions for the test to be satisfied are given, in terms of individual rationality as well as coalitional stability...

  9. Logging a roadside stand to protect scenic values

    Science.gov (United States)

    Philip M. McDonald; Raymond V. Whiteley

    1972-01-01

    A case study on the Challenge Experimental Forest, California, demonstrated that logging along roadsides need not despoil roadside stands. Nearly every tree was "viewed" before marking. Because of the "special-care" procedures followed, combined logging and slash-disposal cost was about twice that of a single-tree selection cut.

  10. The energy cost for balance control during upright standing

    NARCIS (Netherlands)

    Houdijk, J.H.P.; Fickert, R.; van Velzen, J.; van Bennekom, C.A.M.

    2009-01-01

    The aim of this study was to investigate whether balance control during a static upright standing task with and without balance perturbations elicits a significant and meaningful metabolic energy demand and to test whether this energy demand correlates with conventional posturography measures for

  11. Statistical sampling and modelling for cork oak and eucalyptus stands

    NARCIS (Netherlands)

    Paulo, M.J.

    2002-01-01

    This thesis focuses on the use of modern statistical methods to solve problems on sampling, optimal cutting time and agricultural modelling in Portuguese cork oak and eucalyptus stands. The results are contained in five chapters that have been submitted for publication

  12. stem and standing heights in bantu and white south africans

    African Journals Online (AJOL)

    1971-05-29

    May 29, 1971 ... Sitting and standing heights have been recorded for Bantu and Whites, males and females. It !Vas found that Bantu males and females have relatively longer lower extremities than White South African males and females. Anthropo- metric differences account for only about 15% of the actual observed ...

  13. 46 CFR Sec. 2 - Stand-by agreements.

    Science.gov (United States)

    2010-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION B-CONTROL AND UTILIZATION OF PORTS OPERATING CONTRACT Sec. 2 Stand-by agreements. The Director NSA, Maritime Administration, in advance of an emergency, may negotiate... 1901) under the control of the Maritime Administration and allocated for long term exclusive use by the...

  14. 32 CFR 636.30 - Stopping, standing and parking.

    Science.gov (United States)

    2010-07-01

    ... ENFORCEMENT AND CRIMINAL INVESTIGATIONS MOTOR VEHICLE TRAFFIC SUPERVISION (SPECIFIC INSTALLATIONS) Fort... which obstructs traffic. (g) No driver will stand or park a vehicle, whether occupied or not, except...) Within 20 feet upon the approach to any flashing signal, a stop sign, yield sign, or traffic control...

  15. Photosynthetic Characteristics of Five Hardwood Species in a Mixed Stand

    Science.gov (United States)

    Shi-Jean S. Sung; Paul P. Kormanik; Stanley J. Zarnoch

    1999-01-01

    In 1998, photosythesis (Pn) was measured in cherrybark oak, green ash, swamp chestnut oak, sweetgum, and water hickory in a mixed stand established in February 1994. Based on the apparent quantum yield obtained from light response curves, cherrybark oak had the lowest Pn in August whereas sweetgum, green ash, and water hickory were equally active in Pn. Daily August...

  16. The Relationship Between Foot and Pelvic Alignment While Standing

    Directory of Open Access Journals (Sweden)

    Khamis Sam

    2015-06-01

    Full Text Available A normal motion and segmental interrelationship has been determined as a significant factor in normal function. Yet, the relationship between distal segments and pelvic alignment needs further investigation. The aim of this study was to investigate the interrelationship between distal and proximal lower extremity segments while standing and during induced feet hyperpronation. Changes in alignment of the pelvis and lower extremities were measured at a gait laboratory using the VICON 612 computerized motion analysis system. Thirty-five healthy volunteer subjects were recruited. Four randomized repeated-measure standing modes were used: standing directly on the floor and then on three wedges angled at 10°, 15° and 20° to induce bilateral hyperpronation for 20 seconds. A significant (p<0.05 bi-variate relationship was found between the anterior pelvic tilt and thigh internal rotation, in all four standing positions (.41≤r≤.46, in all p<0.014. A combined effect of rotational alignment between segments and the cumulative effect of foot hyperpronation on pelvic tilt revealed that only the shank significantly affected pelvic alignment, acting as a mediator between a foot and a thigh with the thigh having a crude significant effect on the pelvis. When internal rotation of the shank occurs, calcaneal eversion couples with thigh internal rotation and anterior pelvic tilt. It can be concluded that in response to induced hyperpronation, the shank is a pivotal segment in postural adjustment.

  17. Free standing bulk metallic glass microcomponents: Tooling considerations

    DEFF Research Database (Denmark)

    Byrne, Cormac; Eldrup, Morten Mostgaard; Ohnuma, Masato

    2010-01-01

    Bulk metallic glasses have enormous potential for use in small-scale devices such as MEMS and biomedical components. Thermoplastic forging of free standing components poses challenges unlike those seen when forging crystalline materials. Central to these challenges is the simultaneous advantage/disadvantage...

  18. Localization Problem in the 5D Standing Wave Braneworld

    OpenAIRE

    Gogberashvili, Merab; Midodashvili, Pavle; Midodashvili, Levan

    2012-01-01

    We investigate the problem of pure gravitational localization of matter fields within the 5D standing wave braneworld generated by gravity coupled to a phantom-like scalar field. We show that in the case of increasing warp factor there exist normalizable zero modes of spin-0, -1/2, -1, and -2 fields on the brane.

  19. Assessment framework for standardisation activities ResiStand

    NARCIS (Netherlands)

    Stolk, D.J.; Lee, M.D.E. van der; Petiet, P.J.; Liedtke, C.; Lindner, R.; Zetten, J. van; Karppinen, A.; Anson, S.; Kroener, I.

    2017-01-01

    Standardisation is a powerful tool to achieve better interoperability. However, it needs to overcome a lack of interest and modest participation from stakeholders. Also, promising research results are not always used as the basis for new standards. The overall goal of ResiStand is to find new ways

  20. The standing of the curriculum for consumer studies as school ...

    African Journals Online (AJOL)

    ... systems that consistently perform well in international benchmarking tests. The findings of the research point to the standing of the current Consumer Studies curriculum and its perceived impact in the South African context. Recommendations are made regarding the strengthening of the curriculum and its implementation.

  1. Stand-alone solutions, computer networks and extern communications

    International Nuclear Information System (INIS)

    Tarschisch, H.

    1988-01-01

    The advantages of local networks over stand-alone solutions are presented. Of the local networks (LAN), two are presently at the center of attention: the bus and the ring. ETHERNET and the IBM-Token-Ring are described as typical examples. Access to public networks, especially TELEPAC and ISDN, is discussed. 12 figs

  2. Polarization-dependent ponderomotive gradient force in a standing wave

    NARCIS (Netherlands)

    Smorenburg, P.W.; Kanters, J.H.M.; Lassise, A.; Brussaard, G.J.H.; Kamp, L.P.J.; Luiten, O.J.

    2011-01-01

    The ponderomotive force is derived for a relativistic charged particle entering an electromagnetic standing wave with a general three-dimensional field distribution and a nonrelativistic intensity, using a perturbation expansion method. It is shown that the well-known ponderomotive gradient force

  3. Design of a quadrotor flight test stand for system identification

    CSIR Research Space (South Africa)

    Beharie, MM

    2015-01-01

    Full Text Available This paper presents the design, development and construction of a flight test stand for a quadrotor UAV. As opposed to alternate forms of UAV, the power plant in the case of the quadrotor serves a dual purpose of control and propulsion. Since...

  4. Microbial deterioration of stored water for users supplied by stand ...

    African Journals Online (AJOL)

    Two forms of water service delivery in peri-urban settlements in the eThekwini municipal region are communal stand-pipes and household ground-tanks. Water from these sources requires storage prior to use. Previous studies have shown that water quality tends to deteriorate during storage. This study was conducted ...

  5. Increasing cotton stand establishment in soils prone to soil crusting

    Science.gov (United States)

    Many factors can contribute to poor cotton stand establishment, and cotton is notorious for its weak seedling vigor. Soil crusting can be a major factor hindering cotton seedling emergence in many of the cotton production regions of the US and the world. Crusting is mainly an issue in silty soils ...

  6. Assessing the Economic and Environmental Prospects of Stand-By ...

    African Journals Online (AJOL)

    This paper presents an economic analysis of two stand-by power supply options for a typical Nigerian household namely diesel generator plant and solar powered systems. The analysis reveals that solar systems are the most economically viable. The environmental benefits associated with substituting diesel powered ...

  7. Generalized height-diameter models for Populus tremula L. stands

    African Journals Online (AJOL)

    USER

    2010-07-12

    Jul 12, 2010 ... and stand density) into the base height-diameter models increased the accuracy of prediction for P. tremula. .... parameter estimates compared with those obtained with ... using coefficient of determination for non-linear regression (. 2. R ), ..... stochastic height-diameter model for maritime pine ecoregions in.

  8. Compering and Comparing: Stand-Up Comedy and Pedagogy

    Science.gov (United States)

    McCarron, Kevin; Savin-Baden, Maggi

    2008-01-01

    The central argument of this paper is that adopting some of the techniques practised by stand-up comedians can help teachers in higher education challenge students in ways that will ultimately improve the student learning experience overall. It will suggest that developing co-dependent relationships and over-engaging with students is disabling…

  9. Ophiostomatoid fungi associated with declined Pinus pinaster stands in Spain

    Directory of Open Access Journals (Sweden)

    Gonzalo Álvarez

    2015-04-01

    Full Text Available Aim of study: We studied the presence of fungi and distribution patterns in relation to the health status of declining Pinus pinaster trees. Area of study: Trees in two declining stands in Central Spain were allotted to three declining classes. Material and Methods: Trees in two declining stands in Central Spain were allotted to three declining classes (healthy, declining and recently dead and 3 trees of each class were felled in each stand. Wood slides (phloem and xylem were taken at six positions along the trees and samples collected from fungal identification. Main results: A total of 21 fungal taxa were isolated and identified; eleven of these species belonged to the Ophiostomatoid group. Ophiostoma minus was the most frequently isolated fungus and was identified in 22% of the samples, mainly associated to dead and diseased trees. Research highlights: Together these results suggest a putative association of O. minor with the decline in this area, and thus we suggest paying more attention to this fungus as a potential agent of decline in P. pinaster stands.

  10. Sit-to-stand at different periods of pregnancy.

    Science.gov (United States)

    Lou, S Z; Chou, Y L; Chou, P H; Lin, C J; Chen, U C; Su, F C

    2001-03-01

    This study was performed to determine the biomechanics of chair rising by pregnant women. Relative body joint position and ground reaction forces were measured by a motion analysis system and one force plate. Physiological and psychological changes during pregnancy impose postural demands and limit the performance of daily living activities such as rising from sitting to standing position. Twenty-four pregnant women, divided into three groups, were studied performing sit-to-stand transition from an armless and adjustable chair. By kinematic and kinetic analysis, the angles and moments of hip, knee and ankle joints were investigated. The chair height has great influence on knee joint and hip joint moments, but less on ankle joints. In the third trimester for all chair heights, because of a marked increase in abdominal depth, the maximum hip moment is significantly less than that in first trimester, while the maximum knee moment is significantly larger. Pregnant women in third trimester produced larger knee moment during sit-to-stand transition from lower chair height. The mechanism of sit-to-stand is affected by the physical changes of pregnant women at different periods of pregnancy, e.g. increased loading of knee joint and decreased hip joint moment, especially in the last trimester period of pregnancy.

  11. Computer programs for optical dendrometer measurements of standing tree profiles

    Science.gov (United States)

    Jacob R. Beard; Thomas G. Matney; Emily B. Schultz

    2015-01-01

    Tree profile equations are effective volume predictors. Diameter data for building these equations are collected from felled trees using diameter tapes and calipers or from standing trees using optical dendrometers. Developing and implementing a profile function from the collected data is a tedious and error prone task. This study created a computer program, Profile...

  12. Stand tests of the grader unit AKD-2

    Energy Technology Data Exchange (ETDEWEB)

    Kocheskhov, S.M.; Bagley, A.V.; Shalkov, A.V.

    1982-01-01

    Results are presented of stand tests of a static operating grader designed for unmanned extraction of deep beds with programmed control of the unit AKD-2 according to hypsometry of the seam occurrence. Malfunctions in a number of grader assemblies are revealed and eliminated. Parameters are defined which characterize the kinematics and dynamics of the grader mechanism.

  13. Shock stand off Calculations for Hemisphere in Hypersonic Flows

    International Nuclear Information System (INIS)

    Hanif, M.; Ghaffar, A.; Bilal, S.; Zahir, S.; Khan, M.A.

    2004-01-01

    The shape and location of shock has been studied by solving the axi symmetric Navier Stokes Equations for a hemisphere in hypersonic flow. The effect of Mach number on shock stand-off distance has been investigated. It is found that the shock location varies with Mach number and the free stream conditions at a given nose radius. (author)

  14. Standing Slow MHD Waves in Radiatively Cooling Coronal Loops ...

    Indian Academy of Sciences (India)

    The standing slow magneto-acoustic oscillations in cooling coronal loops ... turbation and, eventually, reduces the MHD equations to a 1D system modelling ..... where the function Q is expanded in power series with respect to ǫ, i.e.,. Q = Q0 + ...

  15. Method’s and Test Stand for Electronic PID Controller

    Directory of Open Access Journals (Sweden)

    Cristian Paul Chioncel

    2009-01-01

    Full Text Available The paper presents method’s and a testing stand for electronic controller using for this a signal generator and a digital oscilloscope respectively the virtual instrumentation and the signal acquisitions from the controllers input and output through an data acquisition board and an PC on that Lab View program runs.

  16. Evaluation of three classifiers in mapping forest stand types using ...

    African Journals Online (AJOL)

    EJIRO

    applied for classification of the image. Supervised classification technique using maximum likelihood algorithm is the most commonly and widely used method for land cover classification (Jia and Richards, 2006). In Australia, the maximum likelihood classifier was effectively used to map different forest stand types with high.

  17. Bat use of remnant old-growth redwood stands

    Science.gov (United States)

    William J. Zielinski; Steven T. Gellman

    1999-01-01

    Most of the old-growth redwood (Sequoia sempervirens) in Calfornia has been cut; regenerating forests will probably never resemble those that were harvested, and what old growth remains on private land occurs in small, isolated remnant patches. The landscapes in which these stands occur differ so markedly from their original condition that their...

  18. Ampere hour method of sizing a stand alone photovoltaic system ...

    African Journals Online (AJOL)

    Stand-alone photovoltaic power systems are natural options for application in electrification of remote areas which are not served by the grid electricity supply system. An ampere-hour ... Sizing of the balance-of-system were carefully handled to avoid undersizing or oversizing and subsequent variation in supply reliability.

  19. Log sampling methods and software for stand and landscape analyses.

    Science.gov (United States)

    Lisa J. Bate; Torolf R. Torgersen; Michael J. Wisdom; Edward O. Garton; Shawn C. Clabough

    2008-01-01

    We describe methods for efficient, accurate sampling of logs at landscape and stand scales to estimate density, total length, cover, volume, and weight. Our methods focus on optimizing the sampling effort by choosing an appropriate sampling method and transect length for specific forest conditions and objectives. Sampling methods include the line-intersect method and...

  20. Distribution and dynamics of hayscented fern following stand harvest

    Science.gov (United States)

    Songlin Fei; Peter J. Gould; Melanie J. Kaeser; Kim C. Steiner

    2008-01-01

    The distribution and dynamics of hayscented fern were examined as part of a large-scale study of oak regeneration in Pennsylvania. The study included 69 stands covering 3,333 acres in two physiographic provinces. Hayscented fern was more widely distributed and occurred at higher densities in the Allegheny Plateau physiographic provinces versus the Ridge and Valley...

  1. Standing in the Hallway Improves Students' Understanding of Conformity

    Science.gov (United States)

    Lawson, Timothy J.; Haubner, Richard R.; Bodle, James H.

    2013-01-01

    To help beginning psychology students understand how they are influenced by social pressures to conform, we developed a demonstration designed to elicit their conformity to a small group of students standing in the hallway before class. Results showed the demonstration increased students' recognition of their own tendency to conform, knowledge of…

  2. 48 CFR 13.103 - Use of standing price quotations.

    Science.gov (United States)

    2010-10-01

    ... quotations. 13.103 Section 13.103 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... price quotations. Authorized individuals do not have to obtain individual quotations for each purchase. Standing price quotations may be used if— (a) The pricing information is current; and (b) The Government...

  3. Acoustic evaluation of standing trees : recent research development

    Science.gov (United States)

    Xiping Wang; Robert J. Ross; Peter Carter

    2005-01-01

    This paper presents some research results from recent trial studies on measuring acoustic velocities on standing trees of five softwood species. The relationships between tree velocities measured by time of flight method and log velocities measured by resonance method were evaluated. Theoretical and empirical models were developed for adjusting observed tree velocity...

  4. FlorNExT®, a cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait. stands in Northeastern Portugal

    Directory of Open Access Journals (Sweden)

    Fernando Pérez-Rodríguez

    2016-07-01

    Full Text Available Aim of the study: To introduce and describe FlorNExT®, a free cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait. even-aged stands in the Northeast of Portugal (NE Portugal. Area of study: NE Portugal. Material and methods: FlorNExT® implements a dynamic growth and yield modelling framework which integrates transition functions for dominant height (site index curves and basal area, as well as output functions for tree and stand volume, biomass, and carbon content. Main results: FlorNExT® is freely available from any device with an Internet connection at: http://flornext.esa.ipb.pt/. Research highlights: This application has been designed to make it possible for any stakeholder to easily estimate standing volume, biomass, and carbon content in maritime pine stands from stand data, as well as to estimate growth and yield based on four stand variables: age, density, dominant height, and basal area. FlorNExT® allows planning thinning treatments. FlorNExT® is a fundamental tool to support forest mobilization at local and regional scales in NE Portugal. Keywords: forest management; maritime pine; forest modelling; knowledge transfer tool.

  5. An integer programming model for a forest harvest problem in Pinus pinaster stands

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, T. F.; Cerveira, A.; Mota, A.

    2012-11-01

    The study addresses the special case of a management plan for maritime pine (Pinus pinaster Ait.) in common lands. The study area refers to 4,432 ha of maritime pine stands in North Portugal (Perimetro Florestal do Barroso in the county of Ribeira de Pena), distributed among five common lands called baldio areas. Those lands are co-managed by the Official Forest Services and the local communities, essentially for timber production, using empirical guidance. As the current procedure does not guarantee the best thinning and clear-cutting scheduling, it was considered important to develop easy-to-use models, supported by optimization techniques, to be employed by the forest managers in the harvest planning of these communitarian forests. Planning of the thinning and clear-cutting operations involved certain conditions, such as: (1) the optimal age for harvesting; (2) the maximum stand density permitted; (3) the minimum volume to be cut; (4) the guarantee of incomes for each of the five baldios in at least a two year period; (5) balanced incomes during the length of the projection period. In order to evaluate the sustainability of the wood resources, a set of constraints lower bounding the average ending age was additionally tested. The problem was formulated as an integer linear programming model where the incomes from thinning and clear-cutting are maximized while considering the constraints mentioned above. Five major scenarios were simulated. The simplest one allows for silvicultural constraints only, whereas the other four consider these constraints besides different management options. Two of them introduce joint management of all common areas with or without constraints addressing balanced distribution of incomes during the plan horizon, whilst the other two consider the same options but for individual management of the baldios. The proposed model is easy to apply, providing immediate advantages for short and mid-term planning periods compared to the empirical

  6. Atmospheric deposition in coniferous and deciduous tree stands in Poland

    Science.gov (United States)

    Kowalska, Anna; Astel, Aleksander; Boczoń, Andrzej; Polkowska, Żaneta

    2016-05-01

    The objective of this study was to assess the transformation of precipitation in terms of quantity and chemical composition following contact with the crown layer in tree stands with varied species composition, to investigate the effect of four predominant forest-forming species (pine, spruce, beech, and oak) on the amount and composition of precipitation reaching forest soils, and to determine the sources of pollution in atmospheric precipitation in forest areas in Poland. The amount and chemical composition (pH, electric conductivity, alkalinity, and chloride, nitrate, sulfate, phosphate, ammonium, calcium, magnesium, sodium, potassium, iron aluminum, manganese, zinc, copper, total nitrogen, and dissolved organic carbon contents) of atmospheric (bulk, BP) and throughfall (TF) precipitation were studied from January to December 2010 on twelve forest monitoring plots representative of Polish conditions. The study results provided the basis for the determination of the fluxes of pollutants in the forest areas of Poland and allowed the comparison of such fluxes with values provided in the literature for European forest areas. The transformation of precipitation in the canopy was compared for different tree stands. The fluxes of substances in an open field and under canopy were influenced by the location of the plot, including the regional meteorological conditions (precipitation amounts), vicinity of the sea (effect of marine aerosols), and local level of anthropogenic pollution. Differences between the plots were higher in TF than in BP. The impact of the vegetation cover on the chemical composition of precipitation depended on the region of the country and dominant species in a given tree stand. Coniferous species tended to cause acidification of precipitation, whereas deciduous species increased the pH of TF. Pine and oak stands enriched precipitation with components that leached from the canopy (potassium, manganese, magnesium) to a higher degree than spruce and

  7. Measuring Diagnostic Stand for Experimental Researches in Technology Machining

    Directory of Open Access Journals (Sweden)

    A. E. Dreval'

    2014-01-01

    Full Text Available The paper reviews applied techniques, methods, and structure of the control and measuring means to conduct experimental and scientific researches of cutting processes. Existing research methods in cutting the metals are divided by features, such as essence of methods, the number of records of physical indicators, the number of studied factors, duration of tests. The groups of methods are briefly characterized.The chair "Tool Engineering and Technologies" of BMSTU developed and made a diagnostic stand of control and measurements for conducting research activities in the field of materials processing technology by cutting to define rational technological decisions, when machining, and carry out an analysis of efficiency and economic feasibility of made decisions. The diagnostic stand contains modern the electronic equipment. Record of measuring parameters is made in real time with a possibility for visual representation of read results and mathematical and statistical processing of measurement results. The stand can be used in research laboratories of machine-building enterprises, laboratories of higher education institutions, and other scientific divisions.The paper presents a justification that the stand is reasonable to use for the following: completion and choice of rational cutting modes, workability assessment of new constructional materials, technical and operational characteristics of the processed surfaces, and operational properties of the cutting tools of various producers, choice of optimum geometrical parameters of the cutting tools and brands of the lubricant cooling technological means, as well as the energy consumption for the chosen machining process. The stand allows us to make an assessment of wear resistance and tribology-technical characteristics of tool materials, as well as an accuracy, rigidity, vibration stability of machines, both new and being in operation.

  8. Direct measurement of the intrinsic ankle stiffness during standing.

    Science.gov (United States)

    Vlutters, M; Boonstra, T A; Schouten, A C; van der Kooij, H

    2015-05-01

    Ankle stiffness contributes to standing balance, counteracting the destabilizing effect of gravity. The ankle stiffness together with the compliance between the foot and the support surface make up the ankle-foot stiffness, which is relevant to quiet standing. The contribution of the intrinsic ankle-foot stiffness to balance, and the ankle-foot stiffness amplitude dependency remain a topic of debate in the literature. We therefore developed an experimental protocol to directly measure the bilateral intrinsic ankle-foot stiffness during standing balance, and determine its amplitude dependency. By applying fast (40 ms) ramp-and-hold support surface rotations (0.005-0.08 rad) during standing, reflexive contributions could be excluded, and the amplitude dependency of the intrinsic ankle-foot stiffness was investigated. Results showed that reflexive activity could not have biased the torque used for estimating the intrinsic stiffness. Furthermore, subjects required less recovery action to restore balance after bilateral rotations in opposite directions compared to rotations in the same direction. The intrinsic ankle-foot stiffness appears insufficient to ensure balance, ranging from 0.93±0.09 to 0.44±0.06 (normalized to critical stiffness 'mgh'). This implies that changes in muscle activation are required to maintain balance. The non-linear stiffness decrease with increasing rotation amplitude supports the previous published research. With the proposed method reflexive effects can be ruled out from the measured torque without any model assumptions, allowing direct estimation of intrinsic stiffness during standing. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Sixth-Year Results Following Partial Cutting For Timber and Wildlife Habitat in a Mixed Oak-Sweetgum-Pine Stand on a Minor Creek Terrace in Southeast Louisiana

    Science.gov (United States)

    Brian Roy Lockhart; Norwin E. Linnartz

    2002-01-01

    Hardwood management has primarily focused on highly productive river bottom and upland sites. Less is known about hardwood growth and development on terrace sites. Such sites are usually converted to other uses, especially pine plantations. The objectives of this study, implemented in a minor creek terrace in southeast Louisiana, were to describe changes in stand...

  10. Parameterization of the 3-PG model for Pinus elliottii stands using alternative methods to estimate fertility rating, biomass partitioning and canopy closure

    Science.gov (United States)

    Carlos A. Gonzalez-Benecke; Eric J. Jokela; Wendell P. Cropper; Rosvel Bracho; Daniel J. Leduc

    2014-01-01

    The forest simulation model, 3-PG, has been widely applied as a useful tool for predicting growth of forest species in many countries. The model has the capability to estimate the effects of management, climate and site characteristics on many stand attributes using easily available data. Currently, there is an increasing interest in estimating biomass and assessing...

  11. Stand-level growth and yield component models for red oak-sweetgum forests on Mid-South minor stream bottoms

    Science.gov (United States)

    Emily B. Schultz; J. Clint Iles; Thomas G. Matney; Andrew W. Ezell; James S. Meadows; Theodor D. Leininger; al. et.

    2010-01-01

    Greater emphasis is being placed on Southern bottomland hardwood management, but relatively few growth and yield prediction systems exist that are based on sufficient measurements. We present the aggregate stand-level expected yield and structural component equations for a red oak (Quercus section Lobatae)-sweetgum (Liquidambar styraciflua L.) growth and yield model....

  12. Tree regeneration and future stand development after bark beetle infestation and harvesting in Colorado lodgepole pine stands

    Science.gov (United States)

    Byron J. Collins; Charles C. Rhoades; Robert M. Hubbard; Michael A. Battaglia

    2011-01-01

    In the southern Rocky Mountains, current mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks and associated harvesting have set millions of hectares of lodgepole pine (Pinus contorta var. latifolia Engelm. ex Wats.) forest onto new stand development trajectories. Information about immediate, post-disturbance tree regeneration will provide insight on...

  13. Rehabilitation of Understocked Loblolly-Shortleaf Pine Stands - II. Development of Intermediate and Suppressed Trees Following Release in Natural Stands

    Science.gov (United States)

    James B. Baker; Michael G. Shelton

    1998-01-01

    Development of 86 intermediate and suppressed loblolly pine (Pinus taeda L.) trees, that had been recently released from overtopping pines and hardwoods, was monitored over a 15 year period. The trees were growing in natural stands on good sites (site index = 90 ft at 50 years) that had been recently cut to stocking levels ranging from 10 to 50 percent. At time of...

  14. Stand dynamics following gap-scale exogenous disturbance in a single cohort mixed species stand in Morgan County, Tennessee

    Science.gov (United States)

    Brian S. Hughett; Wayne K. Clatterbuck

    2014-01-01

    Differences in composition, structure, and growth under canopy gaps created by the mortality of a single stem were analyzed using analysis of variance under two scenarios, with stem removed or with stem left as a standing snag. There were no significant differences in composition and structure of large diameter residual stems within upper canopy strata. Some...

  15. Project and Sports Events Management

    OpenAIRE

    Sebastian Madalin MUNTEANU

    2011-01-01

    This paper tries to capture the importance it holds the project management in socio-cultural sector which stands out when we refer to the sport. So when we talk about project management in sport, to consider a much larger vision, a new project management perspective, they involve a responsibility for the implementation of an event with global impact on very long term. Sports projects, as history shows us, played a significant role in developing societies. Also, all major sports industry proje...

  16. Association of standing and lying behavior patterns and incidence of intramammary infection in dairy cows milked with an automatic milking system.

    Science.gov (United States)

    Devries, T J; Deming, J A; Rodenburg, J; Seguin, G; Leslie, K E; Barkema, H W

    2011-08-01

    time of cows milked with an AMS can be managed by providing fresh feed, as well as by pushing up feed, frequently throughout the day. Finally, cows that spend long periods of time (>2.5h) standing following milking may be at higher risk of acquiring a new CNS IMI. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  17. Using the SUBER model for assessing the impact of cork debarking rotation on equivalent annual annuity in Portuguese stands

    International Nuclear Information System (INIS)

    Paulo, J.A.; Tomé, M.

    2017-01-01

    Aim of study: Use the SUBER model to evaluate the influence of the cork debarking rotation period (CDR) on equivalent annual annuity (EAA) value. Area of study: Nine simulated stands, varying in site index (14.4, 15.6, 17.1) and cork quality characteristics (high, medium, low). Material and methods: EAA values were computed considering CDR periods varying from 9 to 14 years, two contrasting structures of cork prices (high and low cork price scenarios), and three discount rate values (0.5%, 2% and 5%). Main results: For discount rates of 0.5% and 2% the impact of different CDR on the EAA is similar. In stands characterized by high to average site index values or high to medium cork quality characteristics, CDR of 9 and 11 years are associated with similar values of EAA. The variation of the CDR in stands characterized by low site index values and/or low cork quality characteristics did not have a relevant effect on the variation of EAA. For the simulations carried out with a discount rate of 5% the EAA decreases with the increase of CDR, indicating that the minimum legal value of 9 years for CDR should be applied. Research highlights: In stands characterized by high to average site index values or high to medium cork quality characteristics, a delay in the debarking may result in a significant increase of cork thickness and, as a result, of cork price. Detailed knowledge of cork and stand characteristics and updated information on cork prices structure and values are essential for the best usage of management tools such as the SUBER model, which can contribute to the decision-making process concerning the debarking operation.

  18. Using the SUBER model for assessing the impact of cork debarking rotation on equivalent annual annuity in Portuguese stands

    Energy Technology Data Exchange (ETDEWEB)

    Paulo, J.A.; Tomé, M.

    2017-11-01

    Aim of study: Use the SUBER model to evaluate the influence of the cork debarking rotation period (CDR) on equivalent annual annuity (EAA) value. Area of study: Nine simulated stands, varying in site index (14.4, 15.6, 17.1) and cork quality characteristics (high, medium, low). Material and methods: EAA values were computed considering CDR periods varying from 9 to 14 years, two contrasting structures of cork prices (high and low cork price scenarios), and three discount rate values (0.5%, 2% and 5%). Main results: For discount rates of 0.5% and 2% the impact of different CDR on the EAA is similar. In stands characterized by high to average site index values or high to medium cork quality characteristics, CDR of 9 and 11 years are associated with similar values of EAA. The variation of the CDR in stands characterized by low site index values and/or low cork quality characteristics did not have a relevant effect on the variation of EAA. For the simulations carried out with a discount rate of 5% the EAA decreases with the increase of CDR, indicating that the minimum legal value of 9 years for CDR should be applied. Research highlights: In stands characterized by high to average site index values or high to medium cork quality characteristics, a delay in the debarking may result in a significant increase of cork thickness and, as a result, of cork price. Detailed knowledge of cork and stand characteristics and updated information on cork prices structure and values are essential for the best usage of management tools such as the SUBER model, which can contribute to the decision-making process concerning the debarking operation.

  19. Clinical ketosis and standing behavior in transition cows.

    Science.gov (United States)

    Itle, A J; Huzzey, J M; Weary, D M; von Keyserlingk, M A G

    2015-01-01

    Ketosis is a common disease in dairy cattle, especially in the days after calving, and it is often undiagnosed. The objective of this study was to compare the standing behavior of dairy cows with and without ketosis during the days around calving to determine if changes in this behavior could be useful in the early identification of sick cows. Serum β-hydroxybutyrate (BHBA) was measured in 184 cows on a commercial dairy farm twice weekly from 2 to 21d after calving. Standing behavior was measured from 7d before calving to 21d after calving using data loggers. Retrospectively, 15 cows with clinical ketosis (3 consecutive BHBA samples >1.2mmol/L and at least one sample of BHBA >2.9mmol/L) were matched with 15 nonketotic cows (BHBA ketosis occurred 4.5±2.1d after calving. Total daily standing time was longer for clinically ketotic cows compared with nonketotic cows during wk -1 (14.3±0.6 vs. 12.0±0.7h/d) and on d 0 (17.2±0.9 vs. 12.7±0.9h/d) but did not differ during the other periods. Clinically ketotic cows exhibited fewer standing bouts compared with nonketotic cows on d 0 only (14.6±1.9 vs. 20.9±1.8bouts/d). Average standing bout duration was also longer for clinically ketotic cows on d 0 compared with nonketotic cows [71.3min/bout (CI: 59.3 to 85.5) vs. 35.8min/bout (CI: 29.8 to 42.9)] but was not different during the other periods. Differences in standing behavior in the week before and on the day of calving may be useful for the early detection of clinical ketosis in dairy cows. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  20. Are the Economically Optimal Harvesting Strategies of Uneven-Aged Pinus nigra Stands Always Sustainable and Stabilizing?

    Directory of Open Access Journals (Sweden)

    Carmen Fullana-Belda

    2013-10-01

    Full Text Available Traditional uneven-aged forest management seeks a balance between equilibrium stand structure and economic profitability, which often leads to harvesting strategies concentrated in the larger diameter classes. The sustainability (i.e., population persistence over time and influence of such economically optimal strategies on the equilibrium position of a stand (given by the stable diameter distribution have not been sufficiently investigated in prior forest literature. This article therefore proposes a discrete optimal control model to analyze the sustainability and stability of the economically optimal harvesting strategies of uneven-aged Pinus nigra stands. For this model, we rely on an objective function that integrates financial data of harvesting operations with a projection matrix model that can describe the population dynamics. The model solution reveals the optimal management schedules for a wide variety of scenarios. To measure the distance between the stable diameter distribution and the economically optimal harvesting strategy distribution, the model uses Keyfitz’s delta, which returns high values for all the scenarios and, thus, suggests that those economically optimal harvesting strategies have an unstabilizing influence on the equilibrium positions. Moreover, the economically optimal harvesting strategies were unsustainable for all the scenarios.

  1. Effect of long-term understory prescribed burning on standing and down dead woody material in dry upland oak forests

    Science.gov (United States)

    Polo, John A.; Hallgren, S.W.; Leslie,, David M.

    2013-01-01

    Dead woody material, long ignored or viewed as a nuisance for forest management, has gained appreciation for its many roles in the forest including wildlife habitat, nutrient storage and cycling, energy for trophic webs, protection of soil, fuel for fire and carbon storage. The growing interest in managing dead woody material has created strong demand for greater understanding of factors controlling amounts and turnover. Prescribed burning, an important management tool, may have strong effects of dead woody material given fire’s capacity to create and consume dead woody material. We determined effects of long-term understory prescribed burning on standing and down woody material in upland oak forests in south-central North America. We hypothesized that as frequency of fire increased in these stands the amount of deadwood would decrease and the fine woody material would decrease more rapidly than coarse woody material. The study was conducted in forests dominated by post oak (Quercus stellata) and blackjack oak (Quercus marilandica) in wildlife management areas where understory prescribed burning had been practiced for over 20 years and the range of burn frequencies was 0 (unburned) fires per decade (FPD) to 4.6 FPD. The amount of deadwood was low compared with more productive forests in southeastern North America. The biomass (24.7 Mg ha-1) and carbon stocks (11.7 Mg ha-1) were distributed among standing dead (22%), coarse woody debris (CWD, dia. > 7.5 cm., 12%), fine woody debris (FWD, dia. prescribed burning influenced the amount and size distribution of standing and down dead woody material. There were two explanations for the lack of a detectable effect. First, a high incidence of severe weather including ice storms and strong winds that produce large amounts of deadwood intermittently in an irregular pattern across the landscape may preclude detecting a strong effect of understory prescribed burning. Second, fire suppression during the first one-half of the

  2. Influence of coarse woody debris on the soricid community in southeastern Coastal Plain pine stands.

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Justin, C.; Castleberry, Steven, B.; Kilgo, John, C.

    2010-07-01

    Shrew abundance has been linked to the presence of coarse woody debris (CWD), especially downed logs, in many regions in the United States. We investigated the importance of CWD to shrew communities in managed upland pine stands in the southeastern United States Coastal Plain. Using a randomized complete block design, 1 of the following treatments was assigned to twelve 9.3-ha plots: removal (n 5 3; all downed CWD _10 cm in diameter and _60 cm long removed), downed (n 5 3; 5-fold increase in volume of downed CWD), snag (n 5 3; 10-fold increase in volume of standing dead CWD), and control (n 5 3; unmanipulated). Shrews (Blarina carolinensis, Sorex longirostris, and Cryptotis parva) were captured over 7 seasons from January 2007 to August 2008 using drift-fence pitfall trapping arrays within treatment plots. Topographic variables were measured and included as treatment covariates. More captures of B. carolinensis were made in the downed treatment compared to removal, and captures of S. longirostris were greater in downed and snag compared to removal. Captures of C. parva did not differ among treatments. Captures of S. longirostris were positively correlated with slope. Our results suggest that abundance of 2 of the 3 common shrew species of the southeastern Coastal Plain examined in our study is influenced by the presence of CWD.

  3. Carbon Storage and Allocation Pattern in Plant Biomass among Different Forest Plantation Stands in Guangdong, China

    Directory of Open Access Journals (Sweden)

    Yuanqi Chen

    2015-03-01

    Full Text Available In order to understand how carbon storage and allocation patterns vary among plantation types, we estimated carbon allocation between above- and below-ground compartments in four subtropical plantations and a naturally recovered shrubland (as a control. Results indicated that the carbon storage and allocation pattern varied greatly among forest types and was highly dependent on specific traits of trees and understory vegetation. The fast-growing species, such as Eucalyptus urophylla, accumulated more carbon in plant biomass. The biomass carbon was about 1.9- and 2.2-times greater than the 10-species mixed plantation and Castanopsis hystrix plantations, respectively. Meanwhile, the plantations sequestered 1.5- to 3-times more carbon in biomass than naturally recovered shrubland. The carbon allocation pattern between above- and below-ground compartments also varied with plantation type and stand age. The ratio of tree root carbon to tree aboveground carbon decreased with stand age for Eucalyptus urophylla and the 10-species mixed plantation. In contrast, the ratio increased for Acacia crassicarpa. Our data suggested that planting the fast-growing species in the degraded land of subtropical China was an effective choice in terms of carbon sequestration. The information about carbon allocation patterns was also valuable for decision making in sustainable forest management and climate change mitigation.

  4. Radiometric Correction of Multitemporal Hyperspectral Uas Image Mosaics of Seedling Stands

    Science.gov (United States)

    Markelin, L.; Honkavaara, E.; Näsi, R.; Viljanen, N.; Rosnell, T.; Hakala, T.; Vastaranta, M.; Koivisto, T.; Holopainen, M.

    2017-10-01

    Novel miniaturized multi- and hyperspectral imaging sensors on board of unmanned aerial vehicles have recently shown great potential in various environmental monitoring and measuring tasks such as precision agriculture and forest management. These systems can be used to collect dense 3D point clouds and spectral information over small areas such as single forest stands or sample plots. Accurate radiometric processing and atmospheric correction is required when data sets from different dates and sensors, collected in varying illumination conditions, are combined. Performance of novel radiometric block adjustment method, developed at Finnish Geospatial Research Institute, is evaluated with multitemporal hyperspectral data set of seedling stands collected during spring and summer 2016. Illumination conditions during campaigns varied from bright to overcast. We use two different methods to produce homogenous image mosaics and hyperspectral point clouds: image-wise relative correction and image-wise relative correction with BRDF. Radiometric datasets are converted to reflectance using reference panels and changes in reflectance spectra is analysed. Tested methods improved image mosaic homogeneity by 5 % to 25 %. Results show that the evaluated method can produce consistent reflectance mosaics and reflectance spectra shape between different areas and dates.

  5. Coordination Control Strategy for AC/DC Hybrid Microgrids in Stand-Alone Mode

    Directory of Open Access Journals (Sweden)

    Dwi Riana Aryani

    2016-06-01

    Full Text Available Interest in DC microgrids is rapidly increasing along with the improvement of DC power technology because of its advantages. To support the integration process of DC microgrids with the existing AC utility grids, the form of hybrid AC/DC microgrids is considered for higher power conversion efficiency, lower component cost and better power quality. In the system, AC and DC portions are connected through interlink bidirectional AC/DC converters (IC with a proper control system and power management. In the stand-alone operation mode of AC/DC hybrid microgrids, the control of power injection through the IC is crucial in order to maintain the system security. This paper mainly deals with a coordination control strategy of IC and a battery energy storage system (BESS converter under stand-alone operation. A coordinated control strategy for the IC, which considers the state of charge (SOC level of BESS and the load shedding scheme as the last resort, is proposed to obtain better power sharing between AC and DC subgrids. The scheme will be tested with a hybrid AC/DC microgrid, using the tool of the PSCAD/EMTDC software.

  6. RADIOMETRIC CORRECTION OF MULTITEMPORAL HYPERSPECTRAL UAS IMAGE MOSAICS OF SEEDLING STANDS

    Directory of Open Access Journals (Sweden)

    L. Markelin

    2017-10-01

    Full Text Available Novel miniaturized multi- and hyperspectral imaging sensors on board of unmanned aerial vehicles have recently shown great potential in various environmental monitoring and measuring tasks such as precision agriculture and forest management. These systems can be used to collect dense 3D point clouds and spectral information over small areas such as single forest stands or sample plots. Accurate radiometric processing and atmospheric correction is required when data sets from different dates and sensors, collected in varying illumination conditions, are combined. Performance of novel radiometric block adjustment method, developed at Finnish Geospatial Research Institute, is evaluated with multitemporal hyperspectral data set of seedling stands collected during spring and summer 2016. Illumination conditions during campaigns varied from bright to overcast. We use two different methods to produce homogenous image mosaics and hyperspectral point clouds: image-wise relative correction and image-wise relative correction with BRDF. Radiometric datasets are converted to reflectance using reference panels and changes in reflectance spectra is analysed. Tested methods improved image mosaic homogeneity by 5 % to 25 %. Results show that the evaluated method can produce consistent reflectance mosaics and reflectance spectra shape between different areas and dates.

  7. Imaging height fluctuations in free-standing graphene membranes

    Science.gov (United States)

    Dorsey, Kyle; Miskin, Marc; Barnard, Arthur; Rose, Peter; Cohen, Itai; McEuen, Paul

    We present a technique based on multi-wavelength interference microscopy to measure the heights of observed ripples in free-standing graphene membranes. Graphene membranes released from a transparent substrate produce interference fringes when viewed in the reflection mode of an inverted microscope(Blees et. al. Nature 524 (7564): 204-207 (2015)). The fringes correspond to corrugation of the membrane as it floats near an interface. A single set of fringes is insufficient to uniquely determine the height profile, as a given fringe spacing can correspond to an increase or decrease in height by λ / 2 . Imaging at multiple wavelengths resolves the ambiguities in phase, and enables unique determination of the height profile of the membrane (Schilling et. al.Phys. Rev. E, 69:021901, 2004). We utilize this technique to map out the height fluctuations in free-standing graphene membranes to answer questions about fundamental mechanical properties of two-dimensional materials.

  8. Customizable nanotweezers for manipulation of free-standing nanostructures

    DEFF Research Database (Denmark)

    Bøggild, Peter; Hansen, Torben Mikael; Mølhave, Kristian

    2001-01-01

    We present a novel nanotweezer device for manipulation and measurement of free-standing nanostructures, where the shape of the tweezer tips can be customized for the application. Electrostatic actuators with submicron interelectrode spacings are fabricated on a batch level using silicon microfabr......We present a novel nanotweezer device for manipulation and measurement of free-standing nanostructures, where the shape of the tweezer tips can be customized for the application. Electrostatic actuators with submicron interelectrode spacings are fabricated on a batch level using silicon...... microfabrication techniques. The actuators are capable of opening and closing with respect to the neutral position, and the full range of actuation exceeds 330 nm. The nanotweezer tips are fabricated using electron beam induced deposition; an electron beam of a scanning electron microscope is focused at the ends...

  9. Modeling of SAR returns from a red pine stand

    Science.gov (United States)

    Lang, R. H.; Kilic, O.; Chauhan, N. S.; Ranson, J.

    1992-01-01

    Bright P-band radar returns from red pine forests have been observed on synthetic aperture radar (SAR) images in Bangor, Maine. A plot of red pine trees was selected for the characterization and modeling to understand the cause of the high P-band returns. The red pine stand under study consisted of mature trees. Diameter at breast height (DBH) measurements were made to determine stand density as a function of tree diameter. Soil moisture and bulk density measurements were taken along with ground rough surface profiles. Detailed biomass measurements of the needles, shoots, branches, and trunks were also taken. These site statistics have been used in a distorted Born approximation model of the forest. Computations indicate that the direct-reflected or the double-bounce contributions from the ground are responsible for the high observed P-band returns for HH polarization.

  10. Electrical conductivity of free-standing mesoporous silicon thin films

    International Nuclear Information System (INIS)

    Khardani, M.; Bouaicha, M.; Dimassi, W.; Zribi, M.; Aouida, S.; Bessais, B.

    2006-01-01

    The effective electrical conductivity of free-standing p + -type porous silicon layers having porosities ranging from 30% to 80% was studied at both experimental and theoretical sides. An Effective Medium Approximation (EMA) model was used as a theoretical support. The porous silicon (PS) films were prepared by the electrochemical etching method for different values of the anodic current density. In order to model the PS electrical conductivity, the free-standing porous layer was assumed to be formed of three phases; vacuum, oxide and Si nanocrystallites. The analytical expression of the electrical conductivity of the Si nanocrystallites was established using the quantum confinement theory. This enables us to correlate the electrical conductivity of the mesoporous film to the value of the effective band gap energy estimated from the absorption coefficient. A perfect agreement between the theoretical and the experimental electrical conductivity values was obtained for all prospected PS porosities

  11. Optimisation of the test policy of stand-by systems

    International Nuclear Information System (INIS)

    Signoret, J.P.; Muron, O.; Cohen, G.

    1980-09-01

    In a nuclear power plant there are several systems which are on stand-by position as, for instance, safety systems. These stand-by systems have to be ready to start as soon as any situation for which they have be designed occurs. A test policy is then necessary in order to know the state of such a system and repair the possible failures. The tests are normally performed at regular intervals of time according to a scheduled sequence. We have already shown during the 'IIIeme Congres National de Fiabilite' held in Perros-Guirec in 1976 how it is possible in this case to find the optimum test interval leading to the best mean availability of the system. It is, in fact, possible, to improve that by considering that if the test interval is fixed 'a priori' this does not allow to take into account information we have on the system state every time [fr

  12. Equipment for linking source stand and film holder carriage

    International Nuclear Information System (INIS)

    Fajt, P.; Zeman, M.

    1987-01-01

    A device is described for precision link-up of a source stand provided with a spring-loaded cam and a film holder carriage provided with an arm with catches. The catches are mechanically connected to a control device firmly connected to the bottom part of the film holder carriage arm. The cam whose extended part is slidably mounted in the cover guide is secured in position with springs fitted from both sides. The control device consists of an electromagnet with armature connected to the control device pull-rod. The pull-rod provides mechanical connection of the catches and the control device. Upon pressing the pushbutton, the catches automatically engage the film holder cariage arm so that the motorized source stand operates without connection to the carriage. This significantly facilitates the operation of the equipment and reduces physical effort of the technician. The most significant advantage is the possibility of immediate change in operation mode. (J.B.). 5 figs

  13. A Cryogenic Test Stand for LHC Quadrupole Magnets

    International Nuclear Information System (INIS)

    Carcagno, R.H.; Huang, Y.; Orris, D.F.; Peterson, T.J.; Rabehl, R.J.

    2004-01-01

    A new test stand for testing LHC interaction region (IR) quadrupole magnets at the Fermilab Magnet Test Facility has been designed and operated. The test stand uses a double bath system with a lambda plate to provide the magnet with a stagnant bath of pressurized He II at 1.9 K and 0.13 MPa. A cryostated magnet 0.91 m in diameter and up to 13 m in length can be accommodated. This paper describes the system design and operation. Issues related to both 4.5 K and 1.9 K operations and magnet quenching are highlighted. An overview of the data acquisition and cryogenics controls systems is also included

  14. Safe lengthening of a drillpipe string by stands

    Energy Technology Data Exchange (ETDEWEB)

    Karapetyan, K.V.; Khrennikov, S.B.; Voyevoda, A.N.

    1979-01-01

    In order to prevent dragging of the block and tackle under the ground block, each drilling rig is equipped with block and tackle lift limiter. However these devices reduce the useful height of the derricks. Studies were carried out to achieve safe conditions for lengthening drillpipe strings with stands and advance of the borehole with a set of drilling stands. The basic precepts of this research were used to design the new drilling rig Uralmash-3000 EUK. In addition an increase of derrick height by 2.5 m was recommended for effective use of production drilling rigs BU-80. In order to lengthen the derrick a special support under the crown block articulated to the upper sections of the feet of the derrick with a frame under the crown block should be used.

  15. [Optimal solution and analysis of muscular force during standing balance].

    Science.gov (United States)

    Wang, Hongrui; Zheng, Hui; Liu, Kun

    2015-02-01

    The present study was aimed at the optimal solution of the main muscular force distribution in the lower extremity during standing balance of human. The movement musculoskeletal system of lower extremity was simplified to a physical model with 3 joints and 9 muscles. Then on the basis of this model, an optimum mathematical model was built up to solve the problem of redundant muscle forces. Particle swarm optimization (PSO) algorithm is used to calculate the single objective and multi-objective problem respectively. The numerical results indicated that the multi-objective optimization could be more reasonable to obtain the distribution and variation of the 9 muscular forces. Finally, the coordination of each muscle group during maintaining standing balance under the passive movement was qualitatively analyzed using the simulation results obtained.

  16. Effect of Forcing Function on Nonlinear Acoustic Standing Waves

    Science.gov (United States)

    Finkheiner, Joshua R.; Li, Xiao-Fan; Raman, Ganesh; Daniels, Chris; Steinetz, Bruce

    2003-01-01

    Nonlinear acoustic standing waves of high amplitude have been demonstrated by utilizing the effects of resonator shape to prevent the pressure waves from entering saturation. Experimentally, nonlinear acoustic standing waves have been generated by shaking an entire resonating cavity. While this promotes more efficient energy transfer than a piston-driven resonator, it also introduces complicated structural dynamics into the system. Experiments have shown that these dynamics result in resonator forcing functions comprised of a sum of several Fourier modes. However, previous numerical studies of the acoustics generated within the resonator assumed simple sinusoidal waves as the driving force. Using a previously developed numerical code, this paper demonstrates the effects of using a forcing function constructed with a series of harmonic sinusoidal waves on resonating cavities. From these results, a method will be demonstrated which allows the direct numerical analysis of experimentally generated nonlinear acoustic waves in resonators driven by harmonic forcing functions.

  17. Models for a stand-alone PV system

    DEFF Research Database (Denmark)

    Hansen, A.D.; Sørensen, Poul Ejnar; Hansen, L.H.

    2001-01-01

    are based on the model descriptions found in the literature. The battery model is developed at UMASS and is known as the Kinetic Battery Model(KiBaM). The other component models in the PV system are based on simple electrical knowledge. The implementation is done using Matlab/Simulink, a simulation program......This report presents a number of models for modelling and simulation of a stand-alone photovoltaic (PV) system with a battery bank verified against a system installed at Risø National Laboratory. The work has been supported by the Danish Ministry ofEnergy, as a part of the activities in the Solar...... Energy Centre Denmark. The study is carried out at Risø National Laboratory with the main purpose to establish a library of simple mathematical models for each individual element of a stand-alone PVsystem, namely solar cells, battery, controller, inverter and load. The models for PV module and battery...

  18. Structura unor arborete exploatabile din regiunea de munte [Structure of some exploitable forest stands from the mountainous area

    Directory of Open Access Journals (Sweden)

    Prodan M

    2005-07-01

    Full Text Available The paper presents one of the first scientific works of the prof. dr. dr. h. c. Michail Prodan, published in the Romanian forestry journal “Viaţa forestieră” (“The forestry life”, in 1940, before starting his prodigious career in Germany. The used data - as in some of his next papers - are from the forest inventories performed in the forest districts of the Romanian Orthodox Religion Found from Bucovina (Eastern Carpathians with the occasion of the forest management plans renewal. Some details: (natural, almost primeval forest stands between 100-200 years, pure or mixed from species Norway spruce, Silver fir, Beech, in total 200,000 records. The analyzed stands were grouped based on Feistmantel class fertility and the basic analysis were the distribution of tree diameters, for these tree species and fertility classes. were computed the theoretical distribution for the diameter classes, using the Charlier approach

  19. Volatile monoterpenes in a stand of Picea abies (L.) Karst

    International Nuclear Information System (INIS)

    Schuermann, W.; Eichstaedter, G.; Steinbrecher, R.; Schoenwitz, R.; Gabriel, R.; Karbach, I.; Zufall, N.; Ziegler, H.

    1992-01-01

    Natural emissions of terpene and their fate in the atmosphere were investigated in a forest stand of the Bayerischer Wald mountains. Terpenes are volatile hydrocarbons whose relevance for air chemistry has increased considerably in the past few years. The investigation compared different sources of terpene in order to determine their strength as a function of meteorological, air-chemical and biological parameters. (orig./BBR) [de

  20. Optimal sizing method for stand-alone photovoltaic power systems

    Energy Technology Data Exchange (ETDEWEB)

    Groumpos, P P; Papageorgiou, G

    1987-01-01

    The total life-cycle cost of stand-alone photovoltaic (SAPV) power systems is mathematically formulated. A new optimal sizing algorithm for the solar array and battery capacity is developed. The optimum value of a balancing parameter, M, for the optimal sizing of SAPV system components is derived. The proposed optimal sizing algorithm is used in an illustrative example, where a more economical life-cycle cost has bene obtained. The question of cost versus reliability is briefly discussed.