WorldWideScience

Sample records for af compressed air

  1. EPA Facility Registry Service (FRS): AIRS_AFS Sub Facilities

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Air Facility System (AFS) contains compliance and permit data for stationary sources regulated by EPA, state and local air pollution agencies. The sub facility...

  2. 29 CFR 1917.154 - Compressed air.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Compressed air. 1917.154 Section 1917.154 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.154 Compressed air. Employees shall be... this part during cleaning with compressed air. Compressed air used for cleaning shall not exceed...

  3. Air Emissions/IGD: EF_AFS

    Data.gov (United States)

    U.S. Environmental Protection Agency — EF_AFS is a subset of facilities from FRS_INTEREST and FRS_FACILITY_SITE which are updated on a monthly basis as part of the Locational Reference Tables (LRT)...

  4. Dental Compressed Air Systems.

    Science.gov (United States)

    1992-03-01

    compressor ex- cept that the piston rings are made of a low friction material (usually a Teflon- composite ) The piston walls are oil-less and all friction... descal - ing. The water-cooled models are smaller, more efficient, and cause less heating of room air. Water-cooled aftercoolers must have an...dry to a dew point of -400C (-400 F). It has high adsorption capacity. (b) Silica Gel , which must be protected from liquid (usually by a layer of

  5. Chapter 22: Compressed Air Evaluation Protocol

    Energy Technology Data Exchange (ETDEWEB)

    Benton, N.

    2014-11-01

    Compressed-air systems are used widely throughout industry for many operations, including pneumatic tools, packaging and automation equipment, conveyors, and other industrial process operations. Compressed-air systems are defined as a group of subsystems composed of air compressors, air treatment equipment, controls, piping, pneumatic tools, pneumatically powered machinery, and process applications using compressed air. A compressed-air system has three primary functional subsystems: supply, distribution, and demand. Air compressors are the primary energy consumers in a compressed-air system and are the primary focus of this protocol. The two compressed-air energy efficiency measures specifically addressed in this protocol are: high-efficiency/variable speed drive (VSD) compressor replacing modulating compressor; compressed-air leak survey and repairs. This protocol provides direction on how to reliably verify savings from these two measures using a consistent approach for each.

  6. Aerometric Information Retrieval System/AIRS Facility Subsystem (AIRS/AFS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Aerometric Information Retrieval System/AIRS Facility Subsystem (AIRS/AFS) is a database that provides information on air releases from various stationary...

  7. Industrial Compressed Air System Energy Efficiency Guidebook.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1993-12-01

    Energy efficient design, operation and maintenance of compressed air systems in industrial plants can provide substantial reductions in electric power and other operational costs. This guidebook will help identify cost effective, energy efficiency opportunities in compressed air system design, re-design, operation and maintenance. The guidebook provides: (1) a broad overview of industrial compressed air systems, (2) methods for estimating compressed air consumption and projected air savings, (3) a description of applicable, generic energy conservation measures, and, (4) a review of some compressed air system demonstration projects that have taken place over the last two years. The primary audience for this guidebook includes plant maintenance supervisors, plant engineers, plant managers and others interested in energy management of industrial compressed air systems.

  8. Efficiency of Compressed Air Energy Storage

    OpenAIRE

    Elmegaard, Brian; Brix, Wiebke

    2011-01-01

    The simplest type of a Compressed Air Energy Storage (CAES) facility would be an adiabatic process consisting only of a compressor, a storage and a turbine, compressing air into a container when storing and expanding when producing. This type of CAES would be adiabatic and would if the machines were reversible have a storage efficiency of 100%. However, due to the specific capacity of the storage and the construction materials the air is cooled during and after compression in practice, making...

  9. Seneca Compressed Air Energy Storage (CAES) Project

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-11-30

    This document provides specifications for the process air compressor for a compressed air storage project, requests a budgetary quote, and provides supporting information, including compressor data, site specific data, water analysis, and Seneca CAES value drivers.

  10. Adiabatic Compression Sensitivity of AF-M315E

    Science.gov (United States)

    2015-07-01

    is pressurized to specific driving pressures into an accumulator tank above a rapid-opening valve. This valve is placed directly above the burst disc...this mission. Of particular interest is the sensitivity of the propellant at elevated temperatures and the resulting system peak pressures and...dynamic response characteristics. For this study, an adiabatic compression U-tube apparatus was used to determine the driving pressure threshold levels

  11. Adiabatic Liquid Piston Compressed Air Energy Storage

    DEFF Research Database (Denmark)

    Petersen, Tage; Elmegaard, Brian; Pedersen, Allan Schrøder

    systems are under development, which show an interesting trend in that they use near-isothermal compression and expansion of air (compression/expansion at almost constant temperature), eliminate compression heat loss and still maintain nearly the same level of energy density as existing CAES systems...... in turbine/generator, heat exchangers, and a large quantity of thermal oil. To improve the economy, it would be relevant to investigate the possibility of replacing the thermal oil by water, for example by injecting the water directly into the air flow between the different compression stages to get a direct...... the system. The compression leads to a significant increase in temperature, and the heat generated is dumped into the ambient. This energy loss results in a low efficiency of the system, and when expanding the air, the expansion leads to a temperature drop reducing the mechanical output of the expansion...

  12. Improve Compressed Air System Performance with AIRMaster+

    Energy Technology Data Exchange (ETDEWEB)

    None

    2005-05-01

    AIRMaster+ provides a systematic apporach for assessing the supply-side performance of compressed air systems. Using plant-specific data, the software effectively evaluates supply-side operational costs for various equipment configurations and system pro

  13. Adiabatic Liquid Piston Compressed Air Energy Storage

    OpenAIRE

    Petersen, Tage; Elmegaard, Brian; Pedersen, Allan Schrøder

    2013-01-01

    This project investigates the potential of a Compressed Air Energy Storage system (CAES system). CAES systems are used to store mechanical energy in the form of compressed air. The systems use electricity to drive the compressor at times of low electricity demand with the purpose of converting the mechanical energy into electricity at times of high electricity demand. Two such systems are currently in operation; one in Germany (Huntorf) and one in the USA (Macintosh, Alabama). In both cases, ...

  14. Efficiency of Compressed Air Energy Storage

    DEFF Research Database (Denmark)

    Elmegaard, Brian; Brix, Wiebke

    2011-01-01

    The simplest type of a Compressed Air Energy Storage (CAES) facility would be an adiabatic process consisting only of a compressor, a storage and a turbine, compressing air into a container when storing and expanding when producing. This type of CAES would be adiabatic and would if the machines...... were reversible have a storage efficiency of 100%. However, due to the specific capacity of the storage and the construction materials the air is cooled during and after compression in practice, making the CAES process diabatic. The cooling involves exergy losses and thus lowers the efficiency...... of the storage significantly. The efficiency of CAES as an electricity storage may be defined in several ways, we discuss these and find that the exergetic efficiency of compression, storage and production together determine the efficiency of CAES. In the paper we find that the efficiency of the practical CAES...

  15. Compressibility of air in fibrous materials

    DEFF Research Database (Denmark)

    Tarnow, Viggo

    1996-01-01

    The dynamic compressibility of air in fibrous materials has been computed for two assumed configurations of fibers which are close to the geometry of real fiber materials. Models with parallel cylinders placed in a regular square lattice and placed randomly are treated. For these models...... the compressibility is computed approximately from the diameter and mean distances between cylinders. This requires calculation of the air temperature, which is calculated for cylinders in a regular lattive by the Wigner-Seitz cell approximation. In the case of random placement, the calculation is done by a summation...

  16. Internal combustion engine with compound air compression

    Energy Technology Data Exchange (ETDEWEB)

    Paul, M.A.; Paul, A.

    1991-10-15

    This patent describes an internal combustion engine in combination with a compound air compression system. It comprises: a reciprocator with at least one cylinder, at least one piston reciprocal in the cylinder and a combustion chamber formed in substantial part by portions of the piston and cylinder, the reciprocator having a drive shaft; a rotary compressor having a drive shaft mechanically coupled to the drive shaft of the reciprocator, the rotary compressor having a Wankel-type, three-lobe, epitrochiodal configuration sides having a conduit conjected to the reciprocator for supplying compressed air to the reciprocator; a turbocharged with a gas turbine and a turbocompressor, the turbocompressor having an air conduit connected to the expander side of the rotary compressor; and a bypass conduit with a valve means connecting the turbocharger to the reciprocator for supplying compressed air directly to the reciprocator wherein the drive shaft of the reciprocator and the drive shaft of the compressor have connecting means for transmitting mechanical energy to the reciprocator at mid to high operating speeds of the engine when the turbocharge supplies compressed air to the rotary compressor and, at least in part, drives the rotary compressor.

  17. Compressed air energy storage technology program

    Science.gov (United States)

    Loscutoff, W. V.

    1980-06-01

    Progress in the development of compressed air energy storage (CAES) technologies for central station electric utility applications is reported. It is reported that the concept improves the effectiveness of a gas turbine using petroleum fuels, could reduce petroleum fuel consumption of electric utility peaking plants, and is technically feasible and economically viable. Specific topics discussed include stability criteria for large underground reservoirs in salt domes, hard rock, and porous rock used for air storage in utility applications and second-generation technologies that have minimal or no dependence on petroleum fuels. The latter includes integration of thermal energy storage, fluidized bed combustion, or coal gasification with CAES.

  18. Working Characteristics of Variable Intake Valve in Compressed Air Engine

    OpenAIRE

    Qihui Yu; Yan Shi; Maolin Cai

    2014-01-01

    A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design c...

  19. Compressed Air Energy Storage in Denmark

    DEFF Research Database (Denmark)

    Salgi, Georges Garabeth; Lund, Henrik

    2006-01-01

    Compressed air energy storage system (CAES) is a technology which can be used for integrating more fluctuating renewable energy sources into the electricity supply system. On a utility scale, CAES has a high feasibility potential compared to other storage technologies. Here, the technology...... is analysed with regard to the Danish energy system. In Denmark, wind power supplies 20% of the electricity demand and 50% is produced by combined heat and power (CHP). The operation of CAES requires high electricity price volatility. However, in the Nordic region, large hydro capacities have so far kept...

  20. University of Arizona Compressed Air Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, Joseph; Muralidharan, Krishna

    2012-12-31

    Boiled down to its essentials, the grant’s purpose was to develop and demonstrate the viability of compressed air energy storage (CAES) for use in renewable energy development. While everyone agrees that energy storage is the key component to enable widespread adoption of renewable energy sources, the development of a viable scalable technology has been missing. The Department of Energy has focused on expanded battery research and improved forecasting, and the utilities have deployed renewable energy resources only to the extent of satisfying Renewable Portfolio Standards. The lack of dispatchability of solar and wind-based electricity generation has drastically increased the cost of operation with these components. It is now clear that energy storage coupled with accurate solar and wind forecasting make up the only combination that can succeed in dispatchable renewable energy resources. Conventional batteries scale linearly in size, so the price becomes a barrier for large systems. Flow batteries scale sub-linearly and promise to be useful if their performance can be shown to provide sufficient support for solar and wind-base electricity generation resources. Compressed air energy storage provides the most desirable answer in terms of scalability and performance in all areas except efficiency. With the support of the DOE, Tucson Electric Power and Science Foundation Arizona, the Arizona Research Institute for Solar Energy (AzRISE) at the University of Arizona has had the opportunity to investigate CAES as a potential energy storage resource.

  1. Seneca Compressed Air Energy Storage (CAES) Project

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2012-11-30

    This report provides a review and an analysis of potential environmental justice areas that could be affected by the New York State Electric & Gas (NYSEG) compress air energy storage (CAES) project and identifies existing environmental burden conditions on the area and evaluates additional burden of any significant adverse environmental impact. The review assesses the socioeconomic and demographic conditions of the area surrounding the proposed CAES facility in Schuyler County, New York. Schuyler County is one of 62 counties in New York. Schuyler County’s 2010 population of 18,343 makes it one of the least populated counties in the State (U.S. Census Bureau, 2010). This report was prepared for WorleyParsons by ERM and describes the study area investigated, methods and criteria used to evaluate this area, and the findings and conclusions from the evaluation.

  2. Elimination of microorganisms from dental operatory compressed air.

    Science.gov (United States)

    De Ciccio, A; Chan, E C

    1998-01-01

    Compressed air is used to power high-speed handpieces, as well as to dry and clean surfaces in the oral cavity during patient treatment, in all dental operatories. The compressed air used in the dental operatories located in large institutions such as universities or hospitals is generally obtained from a central source, and is produced by continually running compressors. In operatories located in private practice settings, compressed air is obtained from small on-site air compressors, which may be run less frequently. A survey was made of operatories in the Montreal area to determine the microbial load of the compressed air produced by air compressors. An air sampler was used to collect compressed air and impinge it on a rotating agar medium surface. Compared to the air produced from compressors in constant use, the air collected from compressors that ran intermittently had a very high microbial load. The efficacy of an apparatus designed to sterilize the contaminated air produced by small, on-site compressors was tested. Called a Purilair, this device heats every particle of inflowing compressed air to 250 degrees C and then forces it through a fine-pore ceramic filter. In three private practice operatories, an in-line Purilair effectively sterilized the air being delivered by small compressors. The same result was obtained in the laboratory when lyophilized spores and cells of Bacillus stearothermophilus and conidia of Penicillium notatum and Aspergillus niger were sprayed into the intake line of the apparatus.

  3. Working Characteristics of Variable Intake Valve in Compressed Air Engine

    Directory of Open Access Journals (Sweden)

    Qihui Yu

    2014-01-01

    Full Text Available A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine.

  4. Working characteristics of variable intake valve in compressed air engine.

    Science.gov (United States)

    Yu, Qihui; Shi, Yan; Cai, Maolin

    2014-01-01

    A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine.

  5. Energy storage by compressed air. [using windpowered pumps

    Science.gov (United States)

    Szego, G. C.

    1973-01-01

    The feasibility of windpower energy storage by compressed air is considered. The system is comprised of a compressor, a motor, and a pump turbine to store air in caverns or aquifiers. It is proposed that storage of several days worth of compressed air up to 650 pounds per square inch can be used to push the aquifier up closer to the container dome and thus initiate piston action by simply compressing air more and more. More energy can be put into it by pressure increase or pushing back the water in the aquifier. This storage system concept has reheat flexibility and lowest cost effectiveness.

  6. Economic Modeling of Compressed Air Energy Storage

    Directory of Open Access Journals (Sweden)

    Rui Bo

    2013-04-01

    Full Text Available Due to the variable nature of wind resources, the increasing penetration level of wind power will have a significant impact on the operation and planning of the electric power system. Energy storage systems are considered an effective way to compensate for the variability of wind generation. This paper presents a detailed production cost simulation model to evaluate the economic value of compressed air energy storage (CAES in systems with large-scale wind power generation. The co-optimization of energy and ancillary services markets is implemented in order to analyze the impacts of CAES, not only on energy supply, but also on system operating reserves. Both hourly and 5-minute simulations are considered to capture the economic performance of CAES in the day-ahead (DA and real-time (RT markets. The generalized network flow formulation is used to model the characteristics of CAES in detail. The proposed model is applied on a modified IEEE 24-bus reliability test system. The numerical example shows that besides the economic benefits gained through energy arbitrage in the DA market, CAES can also generate significant profits by providing reserves, compensating for wind forecast errors and intra-hour fluctuation, and participating in the RT market.

  7. Development of air fuel ratio sensor; A/F sensor no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Sakawa, T.; Hori, M. [Denso Corp., Aichi (Japan); Nakamura, Y. [Toyota Motor Corp., Aichi (Japan)

    1997-10-01

    The Air Fuel Ratio Sensor (A/F sensor), which is applied to a 1997 model year Low Emission Vehicle (LEV) was developed. This sensor enables the detection of the exhaust gas air fuel ratio, both lean and rich of stoichiometric. It has an effective air fuel ratio range from 12 to 18 as required for LEV regulation. It has the fast light off, - within 20 seconds - to minimize exhaust hydrocarbon content. Further, it has fast response time, less than 200 msec, to improve the air fuel ratio controllability. 3 refs., 7 figs.

  8. Seneca Compressed Air Energy Storage (CAES) Project

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2012-11-30

    Compressed Air Energy Storage (CAES) is a hybrid energy storage and generation concept that has many potential benefits especially in a location with increasing percentages of intermittent wind energy generation. The objectives of the NYSEG Seneca CAES Project included: for Phase 1, development of a Front End Engineering Design for a 130MW to 210 MW utility-owned facility including capital costs; project financials based on the engineering design and forecasts of energy market revenues; design of the salt cavern to be used for air storage; draft environmental permit filings; and draft NYISO interconnection filing; for Phase 2, objectives included plant construction with a target in-service date of mid-2016; and for Phase 3, objectives included commercial demonstration, testing, and two-years of performance reporting. This Final Report is presented now at the end of Phase 1 because NYSEG has concluded that the economics of the project are not favorable for development in the current economic environment in New York State. The proposed site is located in NYSEG’s service territory in the Town of Reading, New York, at the southern end of Seneca Lake, in New York State’s Finger Lakes region. The landowner of the proposed site is Inergy, a company that owns the salt solution mining facility at this property. Inergy would have developed a new air storage cavern facility to be designed for NYSEG specifically for the Seneca CAES project. A large volume, natural gas storage facility owned and operated by Inergy is also located near this site and would have provided a source of high pressure pipeline quality natural gas for use in the CAES plant. The site has an electrical take-away capability of 210 MW via two NYSEG 115 kV circuits located approximately one half mile from the plant site. Cooling tower make-up water would have been supplied from Seneca Lake. NYSEG’s engineering consultant WorleyParsons Group thoroughly evaluated three CAES designs and concluded that any

  9. Seneca Compressed Air Energy Storage (CAES) Project

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2012-11-30

    Compressed Air Energy Storage (CAES) is a hybrid energy storage and generation concept that has many potential benefits especially in a location with increasing percentages of intermittent wind energy generation. The objectives of the NYSEG Seneca CAES Project included: for Phase 1, development of a Front End Engineering Design for a 130MW to 210 MW utility-owned facility including capital costs; project financials based on the engineering design and forecasts of energy market revenues; design of the salt cavern to be used for air storage; draft environmental permit filings; and draft NYISO interconnection filing; for Phase 2, objectives included plant construction with a target in-service date of mid-2016; and for Phase 3, objectives included commercial demonstration, testing, and two-years of performance reporting. This Final Report is presented now at the end of Phase 1 because NYSEG has concluded that the economics of the project are not favorable for development in the current economic environment in New York State. The proposed site is located in NYSEG’s service territory in the Town of Reading, New York, at the southern end of Seneca Lake, in New York State’s Finger Lakes region. The landowner of the proposed site is Inergy, a company that owns the salt solution mining facility at this property. Inergy would have developed a new air storage cavern facility to be designed for NYSEG specifically for the Seneca CAES project. A large volume, natural gas storage facility owned and operated by Inergy is also located near this site and would have provided a source of high pressure pipeline quality natural gas for use in the CAES plant. The site has an electrical take-away capability of 210 MW via two NYSEG 115 kV circuits located approximately one half mile from the plant site. Cooling tower make-up water would have been supplied from Seneca Lake. NYSEG’s engineering consultant WorleyParsons Group thoroughly evaluated three CAES designs and concluded that any

  10. Compressed air systems. A guidebook on energy and cost savings

    Energy Technology Data Exchange (ETDEWEB)

    1984-03-30

    This guidebook shows how energy can be saved in compressed air systems. It discusses basic compressed air systems which are typical of those found in industry and describes them and the engineering practices behind them. Energy conservation recommendations follow. These recommendations cover equipment selection, design, maintenance, and operation. Included is information which will help the reader to make economic evaluations of various engineering and equipment alternatives as they affect operations and costs. The appendices include some modern computer based approaches to predicting pressure drop for designing compressed air distribution systems. Also included is a bibliography providing leads for further and more detailed technical information on these and related subjects.

  11. Ultrasound attenuation dependence on air compression or expansion processes

    NARCIS (Netherlands)

    Jakevicius, L.; Demcenko, A.; Mardosaite, R.

    2010-01-01

    In this work variation of ultrasonic attenuation coefficient is analyzed in terms of air compression or expansion processes. In closed spaces changing air volume, the ultrasound attenuation coefficient depends on thermodynamic processes which occur during the air volume change. Two limiting cases ar

  12. Experimental Study on Coal-Breaking Pressure for Compressed Air

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Based on lab model experiments and through the limit analysis, the theoretical formula of calculauoncoal-breaking pressure with compressed air was derived. The experimental result shows that blasting pressure mustexceed 84.0 MPa to break coal with compressive strength of 13.2 MPa. The research provides an important theoretical basis for the design of airshooting mining and industrial tests.

  13. Training Studies with Compressed Air Breathing Apparatus – Methodology, Exercises

    Directory of Open Access Journals (Sweden)

    Buks Roberts

    2015-11-01

    Full Text Available The current article describes topics ranging from the respiratory physiology and the structure of compressed air breathing apparatus to the performance of practical training exercises in an unbreathable environment (hereinafter referred to as UE.

  14. Investigation on wind energy-compressed air power system

    Institute of Scientific and Technical Information of China (English)

    贾光政; 王宣银; 吴根茂

    2004-01-01

    Wind energy is a pollution free and renewable resource widely distributed over China. Aimed at protecting the environment and enlarging application of wind energy, a new approach to application of wind energy by using compressed air power to some extent instead of electricity put forward. This includes: explaining the working principles and characteristics of the wind energy-compressed air power system; discussing the compatibility of wind energy and compressor capacity; presenting the theoretical model and computational simulation of the system. The obtained compressor capacity vs wind power relationship in certain wind velocity range can be helpful in the designing of the wind power-compressed air system. Results of investigations on the application of high-pressure compressed air for pressure reduction led to conclusion that pressure reduction with expander is better than the throttle regulator in energy saving.

  15. Prefeasibility study on compressed air energy storage systems

    Science.gov (United States)

    Elmahgary, Yehia; Peltola, Esa; Sipila, Kari; Vaatainen, Anne

    1991-08-01

    A prefeasibility study on Compressed Air Energy Storage (CAES) systems is presented. The costs of excavating rock caverns for compressed air storage and those for forming suitable storage caverns in existing mines were estimated, and this information was used to calculate the economics of CAES. An analysis of the different possible systems is given following a review of literature on CAES. This was followed by an economic analysis which comprised two separate systems. The first consisted of conventional oil fueled gas turbine plants provided with CAES system. In the second system wind turbines were used to run the compressors which are used in charging the compressed air storage cavern. The results of the current prefeasibility study confirmed the economic attractiveness of the CAES in the first system. Wind turbines still seem, however, to be too expensive to compete with coal power plants. More accurate and straightforward results could be obtained only in a more comprehensive study.

  16. Use of compressed-air storage systems; Einsatz von Druckluftspeichersystemen

    Energy Technology Data Exchange (ETDEWEB)

    Cyphely, I.; Rufer, A.; Brueckmann, Ph.; Menhardt, W.; Reller, A.

    2004-07-01

    This final report issued by the Swiss Federal Office of Energy (SFOE) looks at the use of compressed air as a means of storing energy. Historical aspects are listed and compressed-air storage as an alternative to current ideas that use electrolysis and hydrogen storage is discussed. The storage efficiency advantages of compressed-air storage is stressed and the possibilities it offers for compensating the stochastic nature of electricity production from renewable energy sources are discussed. The so-called BOP (Battery with Oil-hydraulics and Pneumatics) principle for the storage of electricity is discussed and its function is described. The advantages offered by such a system are listed and the development focus necessary is discussed.

  17. Compressed Air System Optimization: Case Study Food Industry in Indonesia

    Science.gov (United States)

    Widayati, Endang; Nuzahar, Hasril

    2016-01-01

    Compressors and compressed air systems was one of the most important utilities in industries or factories. Approximately 10% of the cost of electricity in the industry was used to produce compressed air. Therefore the potential for energy savings in the compressors and compressed air systems had a big challenge. This field was conducted especially in Indonesia food industry or factory. Compressed air system optimization was a technique approach to determine the optimal conditions for the operation of compressors and compressed air systems that included evaluation of the energy needs, supply adjustment, eliminating or reconfiguring the use and operation of inefficient, changing and complementing some equipment and improving operating efficiencies. This technique gave the significant impact for energy saving and costs. The potential savings based on this study through measurement and optimization e.g. system that lowers the pressure of 7.5 barg to 6.8 barg would reduce energy consumption and running costs approximately 4.2%, switch off the compressor GA110 and GA75 was obtained annual savings of USD 52,947 ≈ 455 714 kWh, running GA75 light load or unloaded then obtained annual savings of USD 31,841≈ 270,685 kWh, install new compressor 2x132 kW and 1x 132 kW VSD obtained annual savings of USD 108,325≈ 928,500 kWh. Furthermore it was needed to conduct study of technical aspect of energy saving potential (Investment Grade Audit) and performed Cost Benefit Analysis. This study was one of best practice solutions how to save energy and improve energy performance in compressors and compressed air system.

  18. Economic and technical feasibility study of compressed air storage

    Energy Technology Data Exchange (ETDEWEB)

    1976-03-01

    The results of a study of the economic and technical feasibility of compressed air energy storage (CAES) are presented. The study, which concentrated primarily on the application of underground air storage with combustion turbines, consisted of two phases. In the first phase a general assessment of the technical alternatives, economic characteristics and the institutional constraints associated with underground storage of compressed air for utility peaking application was carried out. The goal of this assessment was to identify potential barrier problems and to define the incentive for the implementation of compressed air storage. In the second phase, the general conclusions of the assessment were tested by carrying out the conceptual design of a CAES plant at two specific sites, and a program of further work indicated by the assessment study was formulated. The conceptual design of a CAES plant employing storage in an aquifer and that of a plant employing storage in a conventionally excavated cavern employing a water leg to maintain constant pressure are shown. Recommendations for further work, as well as directions of future turbo-machinery development, are made. It is concluded that compressed air storage is technically feasible for off-peak energy storage, and, depending on site conditions, CAES plants may be favored over simple cycle turbine plants to meet peak demands. (LCL)

  19. Environmental concerns related to compressed air energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Stottlemyre, J. A.; Craig, R. A.; Loscutoff, W. V.; Boehm, D. W.; Chang, G. C.

    1978-01-01

    The report describes the technologies of compressed air energy storage and some of the environmental concerns associated with siting, construction, operation and decommissioning of such a system. Also described is an ongoing research program, the goal of which is to evaluate methods to control the effects of these environmental factors.

  20. EFFECTS OF COMPRESSED AIR FOAM APPLICATION ON HEAT

    Directory of Open Access Journals (Sweden)

    Adam THOMITZEK

    2015-12-01

    Full Text Available This article evaluates the knowledge obtained in firefighting tests using compressed air foam system (CAFS within a confined space. Six experiments were conducted for verification during the cooling of rooms and the self-extinguishing effect. The simulation was for a fully developed fire within a room. The fuel was chosen to simulate ordinary combustible materials utilized in residential areas. Mantel thermocouples were placed in the rooms to record the temperature changes. Compressed air foam was first applied with a standard fire hose nozzle to the ceiling and then to the epicenter of fire. Fire extinguishing was initiated after reaching the desired temperature in the room. The temperature for the start of fire extinguishing matched the third phase of development of a fire. Fire extinguishing was terminated after no obvious signs of fire were shown in epicenter of fire. The outputs of the experiments were evaluated on the basis of the amount of time passed for the temperature to drop below the suggested limit. Individual experiments were also conducted with various different admixing foaming agents over different locations. In the experiments, it has been verified that the application of compressed air foam has a positive effect on room cooling. Use of a compressed air foaming agent does not allow for the development of steam that can scald firefighters and reduce visibility. Furthermore, the extinguishing agent used is more efficient utilizing less water flow out of the fire area.

  1. Dynamic compressibility of air in porous structures at audible frequencies

    DEFF Research Database (Denmark)

    Lafarge, Denis; Lemarinier, Pavel; Allard, Jean F.;

    1997-01-01

    Measurements of dynamic compressibility of air-filled porous sound-absorbing materials are compared with predictions involving two parametere, the static thermal permeability k'_0 and the thermal characteristic dimension GAMMA'. Emphasis on the notion of dynamic and static thermal permeability...

  2. Improving Compressed Air System Performance: A Sourcebook for Industry

    Energy Technology Data Exchange (ETDEWEB)

    None

    2003-11-01

    NREL will produce this sourcebook for DOE's Industrial Technologies Office as part of a series of documents on industrial energy equipment. The sourcebook is a reference for industrial compressed air system users, outlining opportunities to improve system efficiency.

  3. Legal and regulatory issues affecting compressed air energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, P.L.

    1981-07-01

    Several regulatory and legal issues that can potentially affect implementation of a compressed air energy storage (CAES) system are discussed. This technology involves the compression of air using base load electric power for storage in an underground storage medium. The air is subsequently released and allowed to pass through a turbine to generate electricity during periods of peak demand. The storage media considered most feasible are a mined hard rock cavern, a solution-mined cavern in a salt deposit, and a porous geologic formation (normally an aquifer) of suitable structure. The issues are discussed in four categories: regulatory issues common to most CAES facilities regardless of storage medium, regulatory issues applicable to particular CAES reservoir media, issues related to possible liability from CAES operations, and issues related to acquisition of appropriate property rights for CAES implementation. The focus is on selected federal regulation. Lesser attention is given to state and local regulation. (WHK)

  4. Adiabatic Compression Sensitivity of AF-M315E (Briefing Charts)

    Science.gov (United States)

    2015-07-27

    CONTRACT NUMBER In- House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Phu Quach, Adam Brand, and Greg Warmoth 5d. PROJECT NUMBER...cutting team of US experts for GPIM Background • Rapid isentropic compression of entrained gas bubbles • Closure or opening of valves • External...mechanical shock • Gas introduced by thermal decomp., during priming, or high Q pumping • Bubble collapse increases local temp. & exothermic decomp. T

  5. ADELE adiabatic compressed air energy storage. Status and perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Freund, Sebastian [General Electric Deutschland Holding GmbH, Garching (Germany). GE Global Research Renewable Energy Systems Lab.; Marquardt, Roland; Moser, Peter [RWE Power AG, Essen (Germany). Research and Development Innovative Power Plant Technology

    2013-06-01

    This paper gives an overview about compressed air energy storage (CAES) technology and a summary of the ADELE programme, a multi-year R and D programme undertaken by a consortium led by RWE Power to develop adiabatic (A) CAES technology and commercialise the first plant. The ACAES technology is to utilise waste heat developing upon compression in order to increase the entire efficiency. The ADELE-ING project is to provide the basis for making the decision on the construction of a 85 MW prototype. (orig.)

  6. Thermal reservoir sizing for adiabatic compressed air energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Kere, Amelie; Goetz, Vincent; Py, Xavier; Olives, Regis; Sadiki, Najim [Perpignan Univ. (France). PROMES CNRS UPR 8521; Mercier-Allart, Eric [EDF R et D, Chatou (France)

    2012-07-01

    Despite the operation of the two existing industrial facilities to McIntosh (Alabama), and for more than thirty years, Huntorf (Germany), electricity storage in the form of compressed air in underground cavern (CAES) has not seen the development that was expected in the 80s. The efficiency of this form of storage was with the first generation CAES, less than 50%. The evolving context technique can significantly alter this situation. The new generation so-called Adiabatic CAES (A-CAES) is to retrieve the heat produced by the compression via thermal storage, thus eliminating the necessity of gas to burn and would allow consideration efficiency overall energy of the order of 70%. To date, there is no existing installation of A-CAES. Many studies describe the principal and the general working mode of storage systems by adiabatic compression of air. So, efficiencies of different configurations of adiabatic compression process were analyzed. The aim of this paper is to simulate and analyze the performances of a thermal storage reservoir integrated in the system and adapted to the working conditions of a CAES.

  7. Economics of compressed air energy storage employing thermal energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Schulte, S.C.; Reilly, R.W.

    1979-11-01

    The approach taken in this study is to adopt system design and capital cost estimates from three independent CAES studies (eight total designs) and, by supplying a common set of fuel/energy costs and economic assumptions in conjunction with a common methodology, to arrive at a series of levelized energy costs over the system's lifetime. In addition, some analyses are provided to gauge the sensitivity of these levelized energy costs to fuel and compression energy costs and to system capacity factors. The systems chosen for comparison are of four generic types: conventional CAES, hybrid CAES, adiabatic CAES, and an advanced-design gas turbine (GT). In conventional CAES systems the heat of compression generated during the storage operation is rejected to the environment, and later, during the energy-generation phase, turbine fuel must be burned to reheat the compressed air. In the hybrid systems some of the heat of compression is stored and reapplied later during the generation phase, thereby reducing turbine fuel requirements. The adiabatic systems store adequate thermal energy to eliminate the need for turbine fuel entirely. The gas turbine is included within the report for comparison purposes; it is an advanced-design turbine, one that is expected to be available by 1985.

  8. Geothermally Coupled Well-Based Compressed Air Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, C L [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bearden, Mark D [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Horner, Jacob A [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Appriou, Delphine [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McGrail, B Peter [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-12-01

    Previous work by McGrail et al. (2013, 2015) has evaluated the possibility of pairing compressed air energy storage with geothermal resources in lieu of a fossil-fired power generation component, and suggests that such applications may be cost competitive where geology is favorable to siting both the geothermal and CAES components of such a system. Those studies also note that the collocation of subsurface resources that meet both sets of requirements are difficult to find in areas that also offer infrastructure and near- to mid-term market demand for energy storage. This study examines a novel application for the compressed air storage portion of the project by evaluating the potential to store compressed air in disused wells by amending well casings to serve as subsurface pressure vessels. Because the wells themselves would function in lieu of a geologic storage reservoir for the CAES element of the project, siting could focus on locations with suitable geothermal resources, as long as there was also existing wellfield infrastructure that could be repurposed for air storage. Existing wellfields abound in the United States, and with current low energy prices, many recently productive fields are now shut in. Should energy prices remain stagnant, these idle fields will be prime candidates for decommissioning unless they can be transitioned to other uses, such as redevelopment for energy storage. In addition to the nation’s ubiquitous oil and gas fields, geothermal fields, because of their phased production lifetimes, also may offer many abandoned wellbores that could be used for other purposes, often near currently productive geothermal resources. These existing fields offer an opportunity to decrease exploration and development uncertainty by leveraging data developed during prior field characterization, drilling, and production. They may also offer lower-cost deployment options for hybrid geothermal systems via redevelopment of existing well-field infrastructure

  9. Geothermally Coupled Well-Based Compressed Air Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, Casie L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bearden, Mark D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Horner, Jacob A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cabe, James E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Appriou, Delphine [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McGrail, B. Peter [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-12-20

    Previous work by McGrail et al. (2013, 2015) has evaluated the possibility of pairing compressed air energy storage with geothermal resources in lieu of a fossil-fired power generation component, and suggests that such applications may be cost competitive where geology is favorable to siting both the geothermal and CAES components of such a system. Those studies also note that the collocation of subsurface resources that meet both sets of requirements are difficult to find in areas that also offer infrastructure and near- to mid-term market demand for energy storage. This study examines a novel application for the compressed air storage portion of the project by evaluating the potential to store compressed air in disused wells by amending well casings to serve as subsurface pressure vessels. Because the wells themselves would function in lieu of a geologic storage reservoir for the CAES element of the project, siting could focus on locations with suitable geothermal resources, as long as there was also existing wellfield infrastructure that could be repurposed for air storage. Existing wellfields abound in the United States, and with current low energy prices, many recently productive fields are now shut in. Should energy prices remain stagnant, these idle fields will be prime candidates for decommissioning unless they can be transitioned to other uses, such as redevelopment for energy storage. In addition to the nation’s ubiquitous oil and gas fields, geothermal fields, because of their phased production lifetimes, also may offer many abandoned wellbores that could be used for other purposes, often near currently productive geothermal resources. These existing fields offer an opportunity to decrease exploration and development uncertainty by leveraging data developed during prior field characterization, drilling, and production. They may also offer lower-cost deployment options for hybrid geothermal systems via redevelopment of existing well-field infrastructure

  10. Claw-pole Synchronous Generator for Compressed Air Energy Storage

    Directory of Open Access Journals (Sweden)

    PAVEL Valentina

    2013-05-01

    Full Text Available This paper presents a claw-poles generator for compressed air energy storage systems. It is presented the structure of such a system used for compensating of the intermittency of a small wind energy system. For equipping of this system it is chosen the permanent magnet claw pole synchronous generator obtained by using ring NdFeB permanentmagnets instead of excitation coil. In such a way the complexity of the scheme is reduced and the generator become maintenance free. The new magnetic flux density in the air-gap is calculated by magneticreluctance method and by FEM method and the results are compared with measured values in the old and new generator.

  11. Compressed air energy storage technology program. Annual report for 1979

    Energy Technology Data Exchange (ETDEWEB)

    Loscutoff, W.V.

    1980-06-01

    The objectives of the Compressed Air Energy Storage (CAES) program are to establish stability criteria for large underground reservoirs in salt domes, hard rock, and porous rock used for air storage in utility applications, and to develop second-generation CAES technologies that have minimal or no dependence on petroleum fuels. During the year reported reports have been issued on field studies on CAES on aquifers and in salt, stability, and design criteria for CAES and for pumped hydro-storage caverns, laboratory studies of CAES in porous rock reservoris have continued. Research has continued on combined CAES/Thermal Energy Storage, CAES/Solar systems, coal-fired fluidized bed combustors for CAES, and two-reservoir advanced CAES concepts. (LCL)

  12. Health and efficiency in trimix versus air breathing in compressed air workers.

    Science.gov (United States)

    Van Rees Vellinga, T P; Verhoeven, A C; Van Dijk, F J H; Sterk, W

    2006-01-01

    The Western Scheldt Tunneling Project in the Netherlands provided a unique opportunity to evaluate the effects of trimix usage on the health of compressed air workers and the efficiency of the project. Data analysis addressed 318 exposures to compressed air at 3.9-4.4 bar gauge and 52 exposures to trimix (25% oxygen, 25% helium, and 50% nitrogen) at 4.6-4.8 bar gauge. Results revealed three incidents of decompression sickness all of which involved the use of compressed air. During exposure to compressed air, the effects of nitrogen narcosis were manifested in operational errors and increased fatigue among the workers. When using trimix, less effort was required for breathing, and mandatory decompression times for stays of a specific duration and maximum depth were considerably shorter. We conclude that it might be rational--for both medical and operational reasons--to use breathing gases with lower nitrogen fractions (e.g., trimix) for deep-caisson work at pressures exceeding 3 bar gauge, although definitive studies are needed.

  13. Methods for Sampling and Measurement of Compressed Air Contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Stroem, L.

    1976-10-15

    In order to improve the technique for measuring oil and water entrained in a compressed air stream, a laboratory study has been made of some methods for sampling and measurement. For this purpose water or oil as artificial contaminants were injected in thin streams into a test loop, carrying dry compressed air. Sampling was performed in a vertical run, down-stream of the injection point. Wall attached liquid, coarse droplet flow, and fine droplet flow were sampled separately. The results were compared with two-phase flow theory and direct observation of liquid behaviour. In a study of sample transport through narrow tubes, it was observed that, below a certain liquid loading, the sample did not move, the liquid remaining stationary on the tubing wall. The basic analysis of the collected samples was made by gravimetric methods. Adsorption tubes were used with success to measure water vapour. A humidity meter with a sensor of the aluminium oxide type was found to be unreliable. Oil could be measured selectively by a flame ionization detector, the sample being pretreated in an evaporation- condensation unit

  14. Commercial concepts for adiabatic compressed air energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Freund, Sebastian [General Electric Global Research, Garching (Germany); Schainker, Robert [Electric Power Research Institute, Palo Alto, CA (United States); Moreau, Robert [General Electric Oil and Gas, Florence (Italy)

    2012-07-01

    Adiabatic compressed air energy storage (ACAES) systems offer the potential for efficient large-scale energy storage, almost approaching values typical for pumped hydro. In an ACAES plant, the heat of compression is stored and utilized during the expansion of the air instead of firing natural gas like in commercial CAES. However, no ACAES plants have been commercialized due to challenges with respect to the cost and the heat storage technology. In this study, conducted by EPRI, GE Global Research and GE Oil and Gas, several concepts for ACAES plants are analyzed and their efficiency, complexity and technical risk compared. The components selected for the plants are available either off-the-shelf or near-commercial within a short development time and without the high costs associated with developing a new generation of large custom-made compressors and turbines. The most promising concept for near-term commercialization and low costs turns out to be a two-stage, low-temperature ACAES system. A regenerative (solid) and a recuperative (liquid) thermal storage system have been designed and analyzed for this concept, with the result that the liquid-recuperative system offers a much lower cost and comparable performance. Performance and cost targets for the concepts are 100 MW output per plant for 6 h with a round-trip efficiency above 60% and a capital cost of about $1000/kW. Selections of the turbomachinery for the compression and expansion train from General Electric Oil and Gas are presented for several plant options along with their expansion power range (25..100 MW), round-trip efficiency (66%..70%) and preliminary capital cost estimates (1100..1200 $/kW).

  15. Improving Compressed Air System Performance: A Sourcebook for Industry v3

    Energy Technology Data Exchange (ETDEWEB)

    Ron Marshall, William Scales, Gary Shafer, Paul Shaw, Paul Sheaffer, Rick Stasyshan, H.P.

    2016-03-01

    This sourcebook is designed to provide compressed air system users with a reference that outlines opportunities for system performance improvements. It is not intended to be a comprehensive technical text on improving compressed air systems, but rather a document that makes compressed air system users aware of the performance improvement potential, details some of the significant opportunities, and directs users to additional sources of assistance.

  16. Compressed-air: results of an analysis made for the Clariant company; Ergebnisse der Druckluftanalyse Clariant

    Energy Technology Data Exchange (ETDEWEB)

    Radgen, R. [Fraunhofer-Institut fuer Systemund Innovationsforschung (ISI), Karlsruhe (Germany); Stadelmann, B. [Hochschule fuer Technik und Architektur Luzern (HTA), Horw (Switzerland)

    2005-05-15

    This comprehensive, illustrated report for the Swiss Federal Office of Energy (SFOE) presents the results of a project that examined the compressed-air supply at the facilities of the Clariant company in Muttenz, Switzerland. The various compressors and compressed-air installations in the company's facilities are described and detailed technical data is presented. The control of these systems and the distribution of the compressed air is discussed. Needs, usage and consumption of compressed air is analysed at macro and detail levels. Leakage is looked at as is the dimensioning of the distribution systems. Finally, possibilities for making savings are presented.

  17. AF-TRUST, Air Force Team for Research in Ubiquitous Secure Technology

    Science.gov (United States)

    2010-07-26

    Web Services, Linux and CORBA ) are powerful starting points but leave profound questions unanswered. The AF-TRUST program was supported by teams of...the Component-Oriented ACE ORB (CIAO), www.dre.vanderbilt.eduCIAO, which is an implementation of the Lightweight CORBA AF-TRUST Final Performance...which is widely use implementation of the Real-time Common Object Request Broker Architecture ( CORBA ). CIAO and TAO are widely used, open-source

  18. 29 CFR 1926.913 - Blasting in excavation work under compressed air.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Blasting in excavation work under compressed air. 1926.913... ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Blasting and the Use of Explosives § 1926.913 Blasting in excavation work under compressed air. (a) Detonators...

  19. Theoretical preconditions and technical substantiation for mechanical compressed air drying method application on the railway transport

    Directory of Open Access Journals (Sweden)

    Tatiana RIPOL’-SARAGOSI

    2009-01-01

    Full Text Available The article is related to the compressed air purification for the rolling stock problems. The mechanical method is described as a potential way of the compressed air cooling and purificating. The temperature field at the heat conducting surface engineer function equation is given in the article as well.

  20. A review on compressed-air energy use and energy savings

    Energy Technology Data Exchange (ETDEWEB)

    Saidur, R.; Hasanuzzaman, M. [Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Rahim, N.A. [Department of Electrical Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2010-05-15

    Compressed-air systems account for about 10% of total industrial-energy use for few selected countries as found in literatures. Compressed air is typically one of the most expensive utilities in an industrial facility. This paper describes a comprehensive literature review about compressed air energy use, savings, and payback period of energy efficient strategies. This paper compiles latest literatures in terms of thesis (MS and PhD), journal articles, conference proceedings, web materials, reports, books, handbooks on compressed air energy use, efficiency, energy savings strategies. Computer tools for compressed air analysis have been reviewed and presented in this paper. Various energy-saving measures, such as use of highly efficient motors, VSD, leak prevention, use of outside intake air, reducing pressure drop, recovering waste heat, use of efficient nozzle, and use of variable displacement compressor to save compressed-air energy have been reviewed. Based on review results, it has been found that for an electric motor used in a compressed-air system, a sizeable amount of electric energy and utility bill can be saved using high efficient motors and applying VSDs in matching speed requirements. Also, significant amounts of energy and emission are reducible through various energy-saving strategies. Payback periods for different energy savings measures have been identified and found to be economically viable in most cases. (author)

  1. Integration of Wind Turbines with Compressed Air Energy Storage

    Science.gov (United States)

    Arsie, I.; Marano, V.; Rizzo, G.; Moran, M.

    2009-08-01

    Some of the major limitations of renewable energy sources are represented by their low power density and intermittent nature, largely depending upon local site and unpredictable weather conditions. These problems concur to increase the unit costs of wind power, so limiting their diffusion. By coupling storage systems with a wind farm, some of the major limitations of wind power, such as a low power density and an unpredictable nature, can be overcome. After an overview on storage systems, the Compressed Air Energy Storage (CAES) is analyzed, and the state of art on such systems is discussed. A Matlab/Simulink model of a hybrid power plant consisting of a wind farm coupled with CAES is then presented. The model has been successfully validated starting from the operating data of the McIntosh CAES Plant in Alabama. Time-series neural network-based wind speed forecasting are employed to determine the optimal daily operation strategy for the storage system. A detailed economic analysis has been carried out: investment and maintenance costs are estimated based on literature data, while operational costs and revenues are calculated according to energy market prices. As shown in the paper, the knowledge of the expected available energy is a key factor to optimize the management strategies of the proposed hybrid power plant, allowing to obtain environmental and economic benefits.

  2. Exergy Analysis of the Revolving Vane Compressed Air Engine

    Directory of Open Access Journals (Sweden)

    Alison Subiantoro

    2016-01-01

    Full Text Available Exergy analysis was applied to a revolving vane compressed air engine. The engine had a swept volume of 30 cm3. At the benchmark conditions, the suction pressure was 8 bar, the discharge pressure was 1 bar, and the operating speed was 3,000 rev·min−1. It was found that the engine had a second-law efficiency of 29.6% at the benchmark conditions. The contributors of exergy loss were friction (49%, throttling (38%, heat transfer (12%, and fluid mixing (1%. A parametric study was also conducted. The parameters to be examined were suction reservoir pressure (4 to 12 bar, operating speed (2,400 to 3,600 rev·min−1, and rotational cylinder inertia (0.94 to 2.81 g·mm2. The study found that a higher suction reservoir pressure initially increased the second-law efficiency but then plateaued at about 30%. With a higher operating speed and a higher cylinder inertia, second-law efficiency decreased. As compared to suction pressure and operating speed, cylinder inertia is the most practical and significant to be modified.

  3. Optimization Study on a Single-cylinder Compressed Air Engine

    Institute of Scientific and Technical Information of China (English)

    YU Qihui; CAI Maolin; SHI Yan; XU Qiyue

    2015-01-01

    The current research of compressed air engine (CAE) mainly focused on simulations and system integrations. However, energy efficiency and output torque of the CAE is limited, which restricts its application and popularization. In this paper, the working principles of CAE are briefly introduced. To set a foundation for the study on the optimization of the CAE, the basic mathematical model of working processes is set up. A pressure-compensated valve which can reduce the inertia force of the valve is proposed. To verify the mathematical model, the prototype with the newly designed pressure-compensated intake valve is built and the experiment is carried out, simulation and experimental results of the CAE are conducted, and pressures inside the cylinder and output torque of the CAE are obtained. Orthogonal design and grey relation analysis are utilized to optimize structural parameters. The experimental and optimized results show that, first of all, pressure inside the cylinder has the same changing tendency in both simulation curve and experimental curve. Secondly, the highest average output torque is obtained at the highest intake pressure and the lowest rotate speed. Thirdly, the optimization of the single-cylinder CAE can improve the working efficiency from an original 21.95% to 50.1%, an overall increase of 28.15%, and the average output torque increases also increases from 22.047 5 N • m to 22.439 N • m. This research designs a single-cylinder CAE with pressure-compensated intake valve, and proposes a structural parameters design method which improves the single-cylinder CAE performance.

  4. Compressible Air Entrapment in High-Speed Drop Impacts on Solid Surfaces

    CERN Document Server

    Liu, Yuan; Xu, Lei

    2012-01-01

    Using high-speed photography coupled with optical interference, we experimentally study the air entrapment during a liquid drop impacting a solid substrate. We observe the formation of a compressed air film before the liquid touches the substrate, with internal pressure considerably higher than the atmospheric value. The degree of compression highly depends on the impact velocity, as explained by balancing the liquid deceleration with the large pressure of compressed air. After contact, the air film expands vertically at the edge, reducing its pressure within a few tens of microseconds and producing a thick rim on the perimeter. This thick-rimmed air film subsequently contracts into an air bubble, governed by the complex interaction between surface tension, inertia and viscous drag. Such a process is universally observed for impacts above a few centimeters high.

  5. Project of energy saving in compressed air; Proyecto de ahorro de energia en aire comprimido

    Energy Technology Data Exchange (ETDEWEB)

    Automatizacion, Productividad y Calidad S.A. de C.V. Puebla, (Mexico)

    2005-07-01

    The objective of this project is to reduce the operation costs by means of the energy saving through the use of the compressed air system. For this purpose the solenoid valves controlled per time and the manually acted valves of sphere must be replaced by pneumatic purges that remove from the system the condensed humidity without discharging air and which act automatically when the water reaches the level of unloading in its deposit. The pressure level is the reduction of the operation rank of pressure in the compressors, satisfying the operation requirements of the process equipment. [Spanish] El objetivo de este proyecto es reducir el costo de operacion mediante el ahorro de energia en la utilizacion del sistema de aire comprimido. Para ello se tienen que remplazar las valvulas solenoides controladas por tiempo y valvulas de esfera actuadas manualmente por purgas neumaticas que remueven del sistema la humedad condensada sin descargar aire y que actuan en forma automatica al alcanzar el agua el nivel de descarga en su deposito. El nivel de presion es la reduccion del rango de operacion de presion de los compresores, satisfaciendo los requerimientos de operacion de los equipos de proceso.

  6. Effects of boundary layer and liquid viscosity and compressible air on sloshing characteristics

    Science.gov (United States)

    Zou, Chang-Fang; Wang, De-Yu; Cai, Zhong-Hua

    2015-07-01

    In this paper, numerical investigations for tank sloshing, based on commercial CFD package FLUENT, are performed to study effects of boundary layer grid, liquid viscosity and compressible air on sloshing pressure, wave height and rising time of impact pressure. Also, sloshing experiments for liquids of different viscosity are carried out to validate the numerical results. Through comparison of numerical and experimental results, a computational model including boundary layer grid can predict the sloshing pressure more accurately. Energy dissipation due to viscous friction leads to reduction of sloshing pressure and wave elevation. Sloshing pressure is also reduced because of cushion effect of compressible air. Due to high viscosity damping effect and compressible air effect, the rising time of impact pressure becomes longer. It is also found that liquid viscosity and compressible air influence distribution of dynamic pressure along the vertical tank wall.

  7. Methodology for the energy analysis of compressed air systems; Metodologia para analisis energetico de sistemas de aire comprimido

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, T.; Ambriz, J. J.; Romero, H. [Universidad Autonoma Metropolitana-Iztapalapa, Mexico, D. F. (Mexico)

    1992-12-31

    In this paper a methodology for the diagnosis of compressed air systems, for the identification of the potential energy saving is presented. The methodology consists in detecting the largest number of possible ways of energy saving. For this purpose it is divided into three parts: 1. Compressed air generation. 2. Compressed air distribution. 3. Compressed air users. For each one of the parts, the type of information required to perform the diagnosis study, as well as the necessary measuring equipment needed, is indicated. Afterwards, the possible saving ways that can be found and the ones that can be feasible, are analyzed. [Espanol] En este trabajo se presenta una metodologia para diagnosticar sistemas de aire comprimido, para identificar los potenciales de ahorro de energia. La metodologia consiste en detectar el mayor numero de posibles medidas de ahorro, para lo cual se divide en tres partes: 1. Generacion de aire comprimido. 2. Distribucion del aire comprimido. 3 Usuarios de aire comprimido. Para cada una de las partes se indica el tipo de informacion requerida para realizar el estudio de diagnostico, asi como el uso de equipo necesario de medicion. Despues se analizan las posibles medidas de ahorro que se pueden encontrar y las que pueden ser viables.

  8. Nonlinear property of slightly compressible media permeated with air-filled bubbles

    Institute of Scientific and Technical Information of China (English)

    Bo QIN

    2009-01-01

    Based on the nonlinear oscillation of an air- filled bubble in weakly compressible media at prestressed state, the effective medium method is used to study the nonlinear property of the slightly compressible media permeated with air bubbles. It is this nonlinear oscilla- tion of air bubbles that results in the nonlinear property of the porous media. Numerical results have confirmed that the nonlinearity of the porous media is usually high, though the optimal porosity is very small. Moreover, the nonlinear property is greatly affected by the prestressed state, porosity, and shear modulus of the matrix media.

  9. Design Fabrication And Partial-Analysis Of A 2-Wheeler Prototype That Runs On Compressed Air

    OpenAIRE

    Vinay, P; Srivatsa G R; Venkatesh Datta; Dinesh Kumar A; Ramesha N; Dr. H K Govindaraju

    2015-01-01

    Abstract The primary objective of the project is to create a prototype of a purely air powered motorcycle by retrofitting its internal combustion engine to run on compressed air. Firstly the conventional spark plug was replaced with a solenoid valve. The solenoid valve was initially actuated using a reed switch and magnet duo but then later replaced with an optical crank position sensor circuit due to reasons that include lack of control over the amount of air injected during each stroke and ...

  10. Numerical study on sound vibration of an air-reed instrument with compressible LES

    CERN Document Server

    Miyamoto, Masataka; Takahashi, Kin'ya; Takami, Toshiya; Kobayashi, Taizo; Nishida, Akira; Aoyagi, Mutsumi

    2010-01-01

    Acoustic mechanics of air-reed instruments is investigated numerically with compressible Large-eddy simulation (LES). Taking a two dimensional air-reed instrument model, we have succeeded in reproducing sound oscillations excited in the resonator and have studied the characteristic feature of air-reed instruments, i.e., the relation of the sound frequency with the jet velocity described by the semi-empirical theory developed by Cremer & Ising, Coltman and other authors based on experimental results.

  11. Vapour and air bubble collapse analysis in viscous compressible water

    Directory of Open Access Journals (Sweden)

    Gil Bazanini

    2001-01-01

    Full Text Available Numerical simulations of the collapse of bubbles (or cavities are shown, using the finite difference method, taking into account the compressibility of the liquid, expected to occur in the final stages of the collapse process. Results are compared with experimental and theoretical data for incompressible liquids, to see the influence of the compressibility of the water in the bubble collapse. Pressure fields values are calculated in an area of 800 x 800 mm, for the case of one bubble under the hypothesis of spherical symmetry. Results are shown as radius versus time curves for the collapse (to compare collapse times, and pressure curves in the plane, for pressure fields. Such calculations are new because of their general point of view, since the existing works do not take into account the existence of vapour in the bubble, neither show the pressure fields seen here. It is also expected to see the influence of the compressibility of the water in the collapse time, and in the pressure field, when comparing pressure values.

  12. Experimental Investigation on the Performance of a Compressed-Air Driven Piston Engine

    Directory of Open Access Journals (Sweden)

    Chih-Jie Yu

    2013-03-01

    Full Text Available This study presents an experimental investigation of a piston engine driven by compressed air. The compressed air engine was a modified 100 cm3 internal combustion engine obtained from a motorcycle manufacturer. The experiments in this study used a test bench to examine the power performance and pressure/temperature variations of the compressed air engine at pressures ranging from 5 to 9 bar (absolute pressure. The engine was modified from a 4-stroke to a 2-stroke engine using a cam system driven by a crankshaft and the intake and exhaust valves have a small lift due to this modification. The highest power output of 0.95 kW was obtained at 9 bar and 1320 rpm. The highest torque of 9.99 N·m occurred at the same pressure, but at 465 rpm. The pressure-volume (P-V diagram shows that cylinder pressure gradually increases after the intake valve opens because of the limited lift movement of the intake valve. Similar situations occurred during the exhaust process, restricting the power output of the compressed air engine. The pressure and temperature variation of the air at engine inlet and outlet were recorded during the experiment. The outlet pressure increased from 1.5 bar at 500 rpm to 2.25 bar at 2000 rpm, showing the potential of recycling the compressed air energy by attaching additional cylinders (split-cycle engine. A temperature decrease (from room temperature to 17 °C inside the cylinder was observed. It should be noted that pressures higher than that currently employed can result in lower temperatures and this can cause poor lubrication and sealing issues. The current design of a compressed air engine, which uses a conventional cam mechanism for intake and exhaust, has limited lift movement during operation, and has a restricted flow rate and power output. Fast valve actuation and a large lift are essential for improving the performance of the current compressed air engine. This study presents a power output examination with the pressure

  13. Centralized and Integrated Decentralized Compressed Air Energy Storage for Enhanced Grid Integration of Wind Power

    OpenAIRE

    Madlener, Reinhard; Latz, Jochen

    2009-01-01

    In this paper, we model the economic feasibility of compressed air energy storage (CAES) to improve wind power integration. The Base Case is a wind park with 100 MW of installed capacity and no storage facility. In Variant 1 we add a central CAES system with 90 MW of compressor and 180 MW of generation capacity. The compressed air is stored in a cavern. The CAES system is operated independently of the wind park such that profits from peak power sales at the spot market and reserve power marke...

  14. Compressed air supply in the NZZ printing centre; Druckluftversorgung im Druckzentrum der NZZ

    Energy Technology Data Exchange (ETDEWEB)

    Wohlgenannt, M.

    2001-07-01

    This interview discusses the situation facing suppliers and operators of compressed air equipment that demands increased profitability and ecological compatibility. The interview partners - the head of service and maintenance at the 'Neue Zuercher Zeitung' printing centre near Zurich, Switzerland, which prints one of the most important Swiss dailies, and the head of marketing of Atlas Copco Compressors - discuss how the goal of saving energy and costs was reached, including the use of simulation programs and material-flow book-keeping concepts. Further discussion covers the possibility of providing a supply of compressed air on a volume basis in a type of contracting arrangement instead of just supplying machinery.

  15. Saline Cavern Adiabatic Compressed Air Energy Storage Using Sand as Heat Storage Material

    Directory of Open Access Journals (Sweden)

    Martin Haemmerle

    2017-03-01

    Full Text Available Adiabatic compressed air energy storage systems offer large energy storage capacities and power outputs beyond 100MWel. Salt production in Austria produces large caverns which are able to hold pressure up to 100 bar, thus providing low cost pressurized air storage reservoirs for adiabatic compressed air energy storage plants. In this paper the results of a feasibility study is presented, which was financed by the Austrian Research Promotion Agency, with the objective to determine the adiabatic compressed air energy storage potential of Austria’s salt caverns. The study contains designs of realisable plants with capacities between 10 and 50 MWel, applying a high temperature energy storage system currently developed at the Institute for Energy Systems and Thermodynamics in Vienna. It could be shown that the overall storage potential of Austria’s salt caverns exceeds a total of 4GWhel in the year 2030 and, assuming an adequate performance of the heat exchanger, that a 10MWel adiabatic compressed air energy storage plant in Upper Austria is currently feasible using state of the art thermal turbomachinery which is able to provide a compressor discharge temperature of 400 °C.

  16. A Novel Pumped Hydro Combined with Compressed Air Energy Storage System

    OpenAIRE

    Erren Yao; Xinbing Wang; Liqin Wang; Huanran Wang

    2013-01-01

    A novel pumped hydro combined with compressed air energy storage (PHCA) system is proposed in this paper to resolve the problems of bulk energy storage in the wind power generation industry over an area in China, which is characterised by drought and water shortages. Thermodynamic analysis of the energy storage system, which focuses on the pre-set pressure, storage volume capacity, water air volume ratio, pump performance, and water turbine performance of the storage system, is also presented...

  17. Evaluation of turbine systems for compressed air energy storage plants. Final report for FY 1976

    Energy Technology Data Exchange (ETDEWEB)

    Kartsounes, G.T.

    1976-10-01

    Compressed air energy storage plants for electric utility peak-shaving applications comprise four subsystems: a turbine system, compressor system, an underground air storage reservoir, and a motor/generator. Proposed plant designs use turbines that are derived from available gas and steam turbines with proven reliability. The study examines proposed turbine systems and presents an evaluation of possible systems that may reduce capital cost and/or improve performance. Six new turbine systems are identified for further economic evaluation.

  18. Verification of a fully coupled FE model for tunneling under compressed air

    Energy Technology Data Exchange (ETDEWEB)

    Oettl, G.; Stark, R.F.; Hofstetter, G. [Innsbruck Univ. (Austria). Inst. for Structural Analysis and Strength of Materials

    2001-07-01

    This paper deals with the verification of a fully coupled finite element model for tunneling under compressed air. The formulation is based on mixture theory treating the soil as a three-phase medium with the constituents: deformable porous soil skeleton, water and air. Starting with a brief outline of the governing equations results of numerical simulations of different laboratory tests and of a large-scale in-situ test are presented and compared with experimental data. (orig.)

  19. Demonstration of Isothermal Compressed Air Energy Storage to Support Renewable Energy Production

    Energy Technology Data Exchange (ETDEWEB)

    Bollinger, Benjamin [Sustainx, Incorporated, Seabrook, NH (United States)

    2015-01-02

    This project develops and demonstrates a megawatt (MW)-scale Energy Storage System that employs compressed air as the storage medium. An isothermal compressed air energy storage (ICAESTM) system rated for 1 MW or more will be demonstrated in a full-scale prototype unit. Breakthrough cost-effectiveness will be achieved through the use of proprietary methods for isothermal gas cycling and staged gas expansion implemented using industrially mature, readily-available components.The ICAES approach uses an electrically driven mechanical system to raise air to high pressure for storage in low-cost pressure vessels, pipeline, or lined-rock cavern (LRC). This air is later expanded through the same mechanical system to drive the electric motor as a generator. The approach incorporates two key efficiency-enhancing innovations: (1) isothermal (constant temperature) gas cycling, which is achieved by mixing liquid with air (via spray or foam) to exchange heat with air undergoing compression or expansion; and (2) a novel, staged gas-expansion scheme that allows the drivetrain to operate at constant power while still allowing the stored gas to work over its entire pressure range. The ICAES system will be scalable, non-toxic, and cost-effective, making it suitable for firming renewables and for other grid applications.

  20. 30 CFR 56.13015 - Inspection of compressed-air receivers and other unfired pressure vessels.

    Science.gov (United States)

    2010-07-01

    ... other unfired pressure vessels. 56.13015 Section 56.13015 Mineral Resources MINE SAFETY AND HEALTH... and other unfired pressure vessels. (a) Compressed-air receivers and other unfired pressure vessels... applicable chapters of the National Board Inspection Code, a Manual for Boiler and Pressure Vessel...

  1. 30 CFR 57.13015 - Inspection of compressed-air receivers and other unfired pressure vessels.

    Science.gov (United States)

    2010-07-01

    ... other unfired pressure vessels. 57.13015 Section 57.13015 Mineral Resources MINE SAFETY AND HEALTH... receivers and other unfired pressure vessels. (a) Compressed-air receivers and other unfired pressure... the applicable chapters of the National Board Inspection Code, a Manual for Boiler and Pressure...

  2. Acoustic Localization in Weakly Compressible Elastic Media Permeated with Air Bubbles

    Institute of Scientific and Technical Information of China (English)

    LIANG Bin; ZHU Zhe-Min; CHENG Jian-Chun

    2006-01-01

    @@ The propagation of longitudinal acoustic waves in weakly compressible elastic media permeated with air bubbles is investigated on the basis of the radial pulsation equation of a single bubble. The multiple scattering of waves in such media is rigorously described by using a self-consistent approach.

  3. The effect of compressed air massage on untraumatised rabbit skeletal muscle - a morphometric and ultrastructural study

    Directory of Open Access Journals (Sweden)

    M. A. Gregory

    2004-02-01

    Full Text Available One of the therapeutic uses of massage is to facilitate repairof damaged tissue. A potential hazard of massage is that direct pressure onmuscle is known to damage skeletal myofibres. This study examines theeffect of a new form of massage using compressed air on the morphology ofuntraumatised rabbit skeletal myofibres. Under anaesthetic, the left and right vastus lateralis muscles of 16 New Zealand, white rabbits were treated with 10 minutes of compressed air therapy at 1 Bar using a single hole (5 mm applicator head and control biopsies were taken from the opposite limb. Biopsies were prepared for light microscopy and transmission electronmicroscopy. Morphometry, using image analysis revealed a significant increase in myofibre diameters 10 minutes  (p < 0.001 and 24 hours (p<0.01 after compressed air massage. Six days after treatment diameters were significantly reduced (p < 0.01. Morphologically, myofibres in control specimens were normal. Shortly after compressed air  massage, juxta-nuclear and intermyofibrillar oedema was present and electron-lucent spaces were filled with swollen mitochondria and elements of the sarcoplasmic reticulum (SR. Glycogen and other non-contractile organelles were sometimes aggregated in oedematous, sub-sarcolemmal regions. Twenty four hours after treatment, intermyofibrillar oedema was reduced, but SR swelling remained and many fibres were characterised by focal and large areas of myofibrillar disorganisation. With the exception of occasional swollen elements of the SR and a single internalised nucleus, myofibres morphology had returned to normal 6 days after treatment. Compressed air massage causes less damage to skeletal myofibres than a similar form of localised pressure treatment, deep transverse frictions. Clinicalstudies using this new modality are warranted.

  4. Health effects from air pollution - calculation prices; Sundhedseffekter af luftforurening - beregningspriser

    Energy Technology Data Exchange (ETDEWEB)

    Skou Andersen, Mikael; Seested Nielsen, Jytte; Borgen Soerensen, Peter [DMU, Afdeling for Systemanalyse, Roskilde (Denmark); Frohn, Lise Marie; Solvang Jensen, Steen; Hertel, Ole; Brandt, Joergen; Christensen, Jesper [DMU, Afdeling for Atmosfaerisk Miljoe, Roskilde (Denmark)

    2004-10-01

    The basic aim of research focusing on the accounting of external effects is to provide estimates for the possible benefits of environmental policy projects. There is a demand within the field of environmental economic analysis for evaluations and estimates of the economic benefits arising from pollution reductions. Where benefits arising out of reduced emissions of harmful substances are concerned, these can be estimated according to the avoided damage costs associated with negative pollution impacts. A scientifically based method designed for this purpose has been developed in the pan-European ExternE project via the EU research programmes. The ExternE project has been implemented with the aim of estimating monetary values for externalities attached to air pollution accruing from energy production and transport. For this purpose, complex model-based environmental impact estimations have been coupled with corresponding monetary valuations via the modelling tool, Ecosense. A problem arising in relation to Ecosense methodology has been that externalities are often of local nature - pollution impact depending on the particular locality of the emission and dispersal characteristics in the surrounding environment. Therefore, the economic estimation of the impacts of pollution is based on a location-specific modelling system. (BA)

  5. Potential hazards of compressed air energy storage in depleted natural gas reservoirs.

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, Paul W.; Grubelich, Mark Charles; Bauer, Stephen J.

    2011-09-01

    This report is a preliminary assessment of the ignition and explosion potential in a depleted hydrocarbon reservoir from air cycling associated with compressed air energy storage (CAES) in geologic media. The study identifies issues associated with this phenomenon as well as possible mitigating measures that should be considered. Compressed air energy storage (CAES) in geologic media has been proposed to help supplement renewable energy sources (e.g., wind and solar) by providing a means to store energy when excess energy is available, and to provide an energy source during non-productive or low productivity renewable energy time periods. Presently, salt caverns represent the only proven underground storage used for CAES. Depleted natural gas reservoirs represent another potential underground storage vessel for CAES because they have demonstrated their container function and may have the requisite porosity and permeability; however reservoirs have yet to be demonstrated as a functional/operational storage media for compressed air. Specifically, air introduced into a depleted natural gas reservoir presents a situation where an ignition and explosion potential may exist. This report presents the results of an initial study identifying issues associated with this phenomena as well as possible mitigating measures that should be considered.

  6. Assessment of socio-economic consequences of the Commission's thematic strategy for air pollution; Vurdering af de samfundsoekonomiske konsekvensr af Kommissionens temastrategi for luftforurening

    Energy Technology Data Exchange (ETDEWEB)

    Bach, H.; Skou Andersen, M.; Illerup, J.B.

    2006-06-15

    The Commission has presented a thematic strategy on air pollution and has completed an Impact Assessment, which describes the costs and benefits for the member states. The thematic strategy is to result in a revised air quality directive as well as a revised NEC-directive that determines maximum emissions for a number of air pollution components, the so-called emission ceilings. The air pollution components include sulphur dioxide (SO{sub 2}), nitrogen oxide (NO{sub X}), volatile organic compounds (NMVOC), ammonia (NH{sub 3}) and particulate matters (PM{sub 2,5}). The thematic strategy draws up targets for reductions of the Danish emissions for these components, which have to be met by 2020. These reductions will contribute to a lowering of PM{sub 2,5} concentrations both in Denmark and in neighbouring countries. The concentration of PM{sub 2,5} in the air includes both primary particles that come from emission of particles from e.g. incineration processes, and so-called secondary particles that are generated from emissions of NO{sub X}, SO{sub 2} and NH{sub 3}, and from releases from e.g. vegetation. A very large part of the secondary particles in the air in Denmark stems from emissions of these components in the rest of Europe. A very important condition for a reduction in the concentration of PM{sub 2,5} in the air is thus a reduction of the emissions of these components in all of Europe. (au)

  7. A review on the recent development of solar absorption and vapour compression based hybrid air conditioning with low temperature storage

    Directory of Open Access Journals (Sweden)

    Noor D. N.

    2016-01-01

    Full Text Available Conventional air conditioners or vapour compression systems are main contributors to energy consumption in modern buildings. There are common environmental issues emanating from vapour compression system such as greenhouse gas emission and heat wastage. These problems can be reduced by adaptation of solar energy components to vapour compression system. However, intermittence input of daily solar radiation was the main issue of solar energy system. This paper presents the recent studies on hybrid air conditioning system. In addition, the basic vapour compression system and components involved in the solar air conditioning system are discussed. Introduction of low temperature storage can be an interactive solution and improved economically which portray different modes of operating strategies. Yet, very few studies have examined on optimal operating strategies of the hybrid system. Finally, the findings of this review will help suggest optimization of solar absorption and vapour compression based hybrid air conditioning system for future work while considering both economic and environmental factors.

  8. Compressed air energy storage: Preliminary design and site development program in an aquifer. Volume 2: Utility system planning

    Science.gov (United States)

    1981-07-01

    The performance of an aquifer compressed air energy storage system was studied. The benefits derived from the integration of a compressed air energy storage facility with a hypothetical electrical network are analyzed. Scenarios of 100 percent coal, 50 percent coal and 50 percent nuclear, and 100 percent nuclear base load capacity additions were examined. Favorable economics are indicated when compressed air energy storage is installed as an alternative to combustion turbine peaking capacity on a system with a significant amount of oil fired generation.

  9. Thermal System Analysis and Optimization of Large-Scale Compressed Air Energy Storage (CAES)

    OpenAIRE

    Zhongguang Fu; Ke Lu; Yiming Zhu

    2015-01-01

    As an important solution to issues regarding peak load and renewable energy resources on grids, large-scale compressed air energy storage (CAES) power generation technology has recently become a popular research topic in the area of large-scale industrial energy storage. At present, the combination of high-expansion ratio turbines with advanced gas turbine technology is an important breakthrough in energy storage technology. In this study, a new gas turbine power generation system is coupled ...

  10. Feasibility study of a hybrid wind turbine system – integration with compressed air energy storage

    OpenAIRE

    Sun, Hao; Luo, Xing; Wang, Jihong

    2015-01-01

    Wind has been recognized as one of major realistic clean energy sources for power generation to meet the continuously increased energy demand and to achieve the carbon emission reduction targets. However, the utilisation of wind energy encounters an inevitable challenge resulting from the nature of wind intermittency. To address this, the paper presents the recent research work at Warwick on the feasibility study of a new hybrid system by integrating a wind turbine with compressed air energy ...

  11. Analysis and Optimization of a Compressed Air Energy Storage—Combined Cycle System

    OpenAIRE

    Wenyi Liu; Linzhi Liu; Luyao Zhou; Jian Huang; Yuwen Zhang; Gang Xu; Yongping Yang

    2014-01-01

    Compressed air energy storage (CAES) is a commercial, utility-scale technology that provides long-duration energy storage with fast ramp rates and good part-load operation. It is a promising storage technology for balancing the large-scale penetration of renewable energies, such as wind and solar power, into electric grids. This study proposes a CAES-CC system, which is based on a conventional CAES combined with a steam turbine cycle by waste heat boiler. Simulation and thermodynamic analysis...

  12. Potential and Evolution of Compressed Air Energy Storage: Energy and Exergy Analyses

    OpenAIRE

    Young-Min Kim; Jang-Hee Lee; Seok-Joon Kim; Daniel Favrat

    2012-01-01

    Energy storage systems are increasingly gaining importance with regard to their role in achieving load levelling, especially for matching intermittent sources of renewable energy with customer demand, as well as for storing excess nuclear or thermal power during the daily cycle. Compressed air energy storage (CAES), with its high reliability, economic feasibility, and low environmental impact, is a promising method for large-scale energy storage. Although there are only two large-scale CAES p...

  13. Compressed Air Energy Storage: Optimal Performance and Techno-Economical Indices

    Directory of Open Access Journals (Sweden)

    Peter Vadasz

    1999-06-01

    Full Text Available A thermodynamic and techno-economical analysis of a Compressed Air Energy Storage system subjected to an exogenous periodic electricity price function of the interconnection is presented. The fundamental parameters affecting the thermodynamic performance and the techno-economical cost-benefit indices are identified and corresponding optimisation problems are formulated. The results of the analysis permit to obtain the optimal values of the fundamental plant parameters to be used in the design process.

  14. Technico-economical analysis of a hybrid wave power-air compression storage system

    OpenAIRE

    Hernandez-Torres, David; Bridier, Laurent; David, Mathieu; Lauret, Philippe; Ardiale, Thomas

    2015-01-01

    International audience; This paper presents a technico-economical analysis of a Pelamis wave power generator coupled with a proposed air compression storage system. Ocean wave measurements and forecasts are used from a site near the city of Saint-Pierre in Réunion island, France. The insular context requires both smoothing and forecast of the output power from the wave power system. The storage system is a solution to meet this requirement. Several power network services are defined by the ut...

  15. Factors affecting storage of compressed air in porous-rock reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Allen, R.D.; Doherty, T.J.; Erikson, R.L.; Wiles, L.E.

    1983-05-01

    This report documents a review and evaluation of the geotechnical aspects of porous medium (aquifer) storage. These aspects include geologic, petrologic, geophysical, hydrologic, and geochemical characteristics of porous rock masses and their interactions with compressed air energy storage (CAES) operations. The primary objective is to present criteria categories for the design and stability of CAES in porous media (aquifers). The document will also describe analytical, laboratory, and field-scale investigations that have been conducted.

  16. Development of a WECS for irrigation using a pump actuated by compressed air

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, Armando L.R. de [Pernambuco Univ., Recife, PE (Brazil). Dept. de Engenharia Mecanica. Grupo de Energia Eolica

    1996-12-31

    The Federal University of Pernambuco, pioneer in water pumping research by air compressed developed a 7.3 m diameter windmill that can pump 4,000 l/h with a mean wind velocity of 4 m/s and with 17 m high. This machine has got starting relief and the design tip speed ratio is equal to 2. although this machine has been tested successfully, some problems with dynamic vibrations has been observed with high air pressures. This problem must be solved after the industrialization of the windmill. 7 refs., 7 figs

  17. Design Fabrication And Partial-Analysis Of A 2-Wheeler Prototype That Runs On Compressed Air

    Directory of Open Access Journals (Sweden)

    P Vinay

    2015-08-01

    Full Text Available Abstract The primary objective of the project is to create a prototype of a purely air powered motorcycle by retrofitting its internal combustion engine to run on compressed air. Firstly the conventional spark plug was replaced with a solenoid valve. The solenoid valve was initially actuated using a reed switch and magnet duo but then later replaced with an optical crank position sensor circuit due to reasons that include lack of control over the amount of air injected during each stroke and also for more precise control over the opening and closing of the valve. The torque brake power indicated power air consumption rate of the engine under load are calculated. Separate mounts for the modified engine and the cylindrical storage unit are designed and analysed using Catia v4. Also possible ways of future scope of the prototype are mentioned.

  18. A Coupled Thermo-Hydro-Mechanical Model of Jointed Hard Rock for Compressed Air Energy Storage

    Directory of Open Access Journals (Sweden)

    Xiaoying Zhuang

    2014-01-01

    Full Text Available Renewable energy resources such as wind and solar are intermittent, which causes instability when being connected to utility grid of electricity. Compressed air energy storage (CAES provides an economic and technical viable solution to this problem by utilizing subsurface rock cavern to store the electricity generated by renewable energy in the form of compressed air. Though CAES has been used for over three decades, it is only restricted to salt rock or aquifers for air tightness reason. In this paper, the technical feasibility of utilizing hard rock for CAES is investigated by using a coupled thermo-hydro-mechanical (THM modelling of nonisothermal gas flow. Governing equations are derived from the rules of energy balance, mass balance, and static equilibrium. Cyclic volumetric mass source and heat source models are applied to simulate the gas injection and production. Evaluation is carried out for intact rock and rock with discrete crack, respectively. In both cases, the heat and pressure losses using air mass control and supplementary air injection are compared.

  19. Experimental Investigation on the Effect of Phase Change Materials on Compressed Air Expansion in CAES Plants

    Directory of Open Access Journals (Sweden)

    Beatrice Castellani

    2015-07-01

    Full Text Available The integration of renewable energy in the electrical grid is challenging due to the intermittent and non-programmable generated electric power and to the transmission of peak power levels. Several energy storage technologies have been studied to find a solution to these issues. In particular, compressed air energy storage (CAES plants work by pumping and storing air into a vessel or in an underground cavern; then when energy is needed, the pressurized air is expanded in an expansion turbine. Several CAES configurations have been proposed: diabatic, adiabatic and isothermal. The isothermal process seems to be the most promising to improve the overall efficiency. It differs from conventional CAES approaches as it employs near-isothermal compression and expansion. Currently, there are no commercial isothermal CAES implementations worldwide, but several methods are under investigation. In this paper, the use of phase change materials (PCM for isothermal air expansion is discussed. Air expansion tests in presence of PCM were carried out in a high-pressure vessel in order to analyze the effect of PCM on the process. Results show that in presence of PCM near isothermal expansion conditions occur and therefore they affect positively the value of the obtainable expansion work.

  20. LCA af genbrug af mursten

    DEFF Research Database (Denmark)

    Møller, Jacob; Damgaard, Anders; Astrup, Thomas Fruergaard

    Der er gennemført en livscyklusbaseret miljøvurdering af genbrug af mursten. Modelleringen er baseret på, hvordan Virksomheden ”Gamle Mursten” forbereder de gamle mursten med henblik på, at de kan genbruges i nybyggeri. Som alternativ til direkte genbrug nedknuses murstensaffaldet og anvendes som...

  1. Compressed air energy storage in depleted natural gas reservoirs: effects of porous media and gas mixing

    Science.gov (United States)

    Oldenburg, C. M.; Pan, L.

    2015-12-01

    Although large opportunities exist for compressed air energy storage (CAES) in aquifers and depleted natural gas reservoirs, only two grid-scale CAES facilities exist worldwide, both in salt caverns. As such, experience with CAES in porous media, what we call PM-CAES, is lacking and we have relied on modeling to elucidate PM-CAES processes. PM-CAES operates similarly to cavern CAES. Specifically, working gas (air) is injected through well(s) into the reservoir compressing the cushion gas (existing air in the reservoir). During energy recovery, high-pressure air from the reservoir flows first into a recuperator, then into an expander, and subsequently is mixed with fuel in a combustion turbine to produce electricity, thereby reducing compression costs. Energy storage in porous media is complicated by the solid matrix grains which provide resistance to flow (via permeability in Darcy's law); in the cap rock, low-permeability matrix provides the seal to the reservoir. The solid grains also provide storage capacity for heat that might arise from compression, viscous flow effects, or chemical reactions. The storage of energy in PM-CAES occurs variably across pressure gradients in the formation, while the solid grains of the matrix can release/store heat. Residual liquid (i.e., formation fluids) affects flow and can cause watering out at the production well(s). PG&E is researching a potential 300 MW (for ten hours) PM-CAES facility in a depleted gas reservoir near Lodi, California. Special considerations exist for depleted natural gas reservoirs because of mixing effects which can lead to undesirable residual methane (CH4) entrainment and reactions of oxygen and CH4. One strategy for avoiding extensive mixing of working gas (air) with reservoir CH4 is to inject an initial cushion gas with reduced oxygen concentration providing a buffer between the working gas (air) and the residual CH4 gas. This reduces the potential mixing of the working air with the residual CH4

  2. Technical and economic assessment of fluidized-bed-augmented compressed-air energy-storage system. Volume 1: Executive summary

    Science.gov (United States)

    Giramonti, A. J.; Lessard, R. D.; Merrick, D.; Hobson, M. J.

    1981-09-01

    An energy storage system for electric utility peak load applications is a modified gas turbine power system utilizing underground storage of very high pressure air. The compressed air energy storage (CAES) concept involves using off peak electricity generated from indigenous coal or nuclear sources to compress air, storing the air in large underground facilities, and withdrawing the air during peak load periods when it would be heated by combustion and expanded through gas turbines to generate power. The attractiveness of the CAES concept is based upon its potential to supply competitively priced peaking energy, to reduce peak load power plant dependence on petroleum based fuels, and to provide a means for leveling the utility system load demand. Therefore, a technical and economic assessment of coal fired fluidized bed combustor/compressed air energy storage systems was performed and is described.

  3. Time-resolved imaging of a compressible air disc under a drop impacting on a solid surface

    KAUST Repository

    Li, Erqiang

    2015-09-07

    When a drop impacts on a solid surface, its rapid deceleration is cushioned by a thin layer of air, which leads to the entrapment of a bubble under its centre. For large impact velocities the lubrication pressure in this air layer becomes large enough to compress the air. Herein we use high-speed interferometry, with 200 ns time-resolution, to directly observe the thickness evolution of the air layer during the entire bubble entrapment process. The initial disc radius and thickness shows excellent agreement with available theoretical models, based on adiabatic compression. For the largest impact velocities the air is compressed by as much as a factor of 14. Immediately following the contact, the air disc shows rapid vertical expansion. The radial speed of the surface minima just before contact, can reach 50 times the impact velocity of the drop.

  4. Optimization of the Starting by compressed air techniques; Optimizacion del Arranque en el sutiraje mediante tecnicas de aire comprimido

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    High-pressure compressed air shots have been begun to use for coal stop caving in horizontal sublevel caving workings, as alternative to explosives, since they do not condition the winning cycles and they produce a smaller deterioration in the vein walls. In spite of those advantages, different parameters influence on shot result is not known. For this reason, a research project has been carried out in order to improve the high-pressure compressed air technique to extend the system implementation and to reduce the winning costs in the sublevel caving workings. The research works have consisted of a numerical model development and reduced scale and real scale tests. The model describes fragile material fragmentation under dynamical loadings and it has been implemented in a code. The tests allow to study the different parameter influence and to validate the numerical model. The main research results are, on the one hand, a numerical model that allows to define the best shot plan for user's working conditions and, on the other hand, the great influence of the air volume on the disruptive strength has been proven. (Author)

  5. Compressed air energy storage preliminary design and site development program in an aquifer. Turbomachinery design

    Science.gov (United States)

    Berman, P. A.; Bonk, J. S.; Kobett, W. F.; Kosanovich, N. S.; Long, L. J.; Marinacci, D. J.

    1981-07-01

    Compressed Air Energy Storage (CAES) is a means of storing electrical energy generated by utility baseload power plants during off-peak hours. This stored energy will be used during periods of high demand. Compressed Air Energy Storage (CAES) system uses off-peak power from an electrical grid to operate an electric dynamo. This is used as a motor to drive a compressor train that charges atmospheric air at elevated pressure into an underground aquifer. During high electrical demand periods, the pressurized air is withdrawn from the aquifer and channeled to combustors where it is heated and then expanded through a combustion turbine. The turbine drives the electric dynamo, being operated as a generator, to supply power back to the grid. Since the CAES turbine train is divorced from the compressor during power generation, the net output power is about three times that of a normal combustion turbine. Although the fuel consumption rate is nearly the same, the heat rate is much lower.

  6. Parametric analysis of a combined dew point evaporative-vapour compression based air conditioning system

    Directory of Open Access Journals (Sweden)

    Shailendra Singh Chauhan

    2016-09-01

    Full Text Available A dew point evaporative-vapour compression based combined air conditioning system for providing good human comfort conditions at a low cost has been proposed in this paper. The proposed system has been parametrically analysed for a wide range of ambient temperatures and specific humidity under some reasonable assumptions. The proposed system has also been compared from the conventional vapour compression air conditioner on the basis of cooling load on the cooling coil working on 100% fresh air assumption. The saving of cooling load on the coil was found to be maximum with a value of 60.93% at 46 °C and 6 g/kg specific humidity, while it was negative for very high humidity of ambient air, which indicates that proposed system is applicable for dry and moderate humid conditions but not for very humid conditions. The system is working well with an average net monthly power saving of 192.31 kW h for hot and dry conditions and 124.38 kW h for hot and moderate humid conditions. Therefore it could be a better alternative for dry and moderate humid climate with a payback period of 7.2 years.

  7. Implementing a Compressed Air System Leak Management Program at an Automotive Plant (Visteon's Monroe Plant)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2001-01-01

    The energy team at Visteon’s Monroe plant, formerly owned by Ford Motor Company, implemented an ongoing compressed air system leak management program. The team developed an approach that combined a traditional “find and fix” effort with an innovative implementation and marketing program. As a result of the leak management program, compressed air system consumption was reduced by more than 50% on a per production unit basis.

  8. Comparative study of air conditioning systems with vapor compression chillers using the concept of green buildings

    Directory of Open Access Journals (Sweden)

    Gutenberg da Silva Pereira

    2015-10-01

    Full Text Available This paper sets out to compare two different cooling systems that use vapor compression chillers for air conditioning environments. It was proposed to compare different operations in isolated and combined action operations. These operations are evaluated in the concepts of green buildings. A mathematical model was developed based on the principles of mass and energy conservation and complemented by various functions so as to determine the thermophysical properties and efficiencies of the compressors. The equations of the model were solved by the EES (Engineering Equation Solver program. The model evaluates the influence of the main HVAC operating parameters of the chilled water system when operating under three different configurations. The results showed that the system with a differentiated compression presents a COP equal to that of the system with screw chillers in the range  0-300 RTs, and a COP hat is on average 9% higher in the range 400-800 RTs.

  9. Class B Fire-Extinguishing Performance Evaluation of a Compressed Air Foam System at Different Air-to-Aqueous Foam Solution Mixing Ratios

    Directory of Open Access Journals (Sweden)

    Dong-Ho Rie

    2016-06-01

    Full Text Available The purpose of this research is to evaluate the fire-extinguishing performance of a compressed air foam system at different mixing ratios of pressurized air. In this system, compressed air is injected into an aqueous solution of foam and then discharged. The experimental device uses an exclusive fire-extinguishing technology with compressed air foam that is produced based on the Canada National Laboratory and UL (Underwriters Laboratories 162 standards, with a 20-unit oil fire model (Class B applied as the fire extinguisher. Compressed air is injected through the air mixture, and results with different air-to-aqueous solution foam ratios of 1:4, 1:7, and 1:10 are studied. In addition, comparison experiments between synthetic surfactant foam and a foam type which forms an aqueous film are carried out at an air-to-aqueous solution foam ratio of 1:4. From the experimental results, at identical discharging flows, it was found that the fire-extinguishing effect of the aqueous film-forming foam is greatest at an air-to-aqueous solution foam ratio of 1:7 and weakest at 1:10. Moreover, the fire-extinguishing effect of the aqueous film-forming foam in the comparison experiments between the aqueous film-forming foam and the synthetic surfactant foam is greatest.

  10. Design issues for compressed air energy storage in sealed underground cavities

    Directory of Open Access Journals (Sweden)

    P. Perazzelli

    2016-06-01

    Full Text Available Compressed air energy storage (CAES systems represent a new technology for storing very large amount of energy. A peculiarity of the systems is that gas must be stored under a high pressure (p = 10–30 MPa. A lined rock cavern (LRC in the form of a tunnel or shaft can be used within this pressure range. The rock mass surrounding the opening resists the internal pressure and the lining ensures gas tightness. The present paper investigates the key aspects of technical feasibility of shallow LRC tunnels or shafts under a wide range of geotechnical conditions. Results show that the safety with respect to uplift failure of the rock mass is a necessary but not a sufficient condition for assessing feasibility. The deformation of the rock mass should also be kept sufficiently small to preserve the integrity of the lining and, especially, its tightness. If the rock is not sufficiently stiff, buckling or fatigue failure of the steel lining becomes more decisive when evaluating the feasible operating air pressure. The design of the concrete plug that seals the compressed air stored in the container is another demanding task. Numerical analyses indicate that in most cases, the stability of the rock mass under the plug loading is not a decisive factor for plug design.

  11. Compressed air massage: repeated treatment causes less muscle oedema than a single treatment

    Directory of Open Access Journals (Sweden)

    M. A. Gregory

    2007-02-01

    Full Text Available Compressed air massage is a new treatment modality that has been shown to cause skeletal muscle capillary dilation for up to 24 hours after a single treatment and significantly hastens healing of diabetic ulcers. This study compares the effect of one treatment of a single muscle group, with repeated treatments of several muscle groups. Methods: Four vervet monkeys underwent one, 15 min, treatment of compressed air massage at 1 Bar, to the tibialis anterior muscle and four animals received similar treatment to the whole lower leg on three consecutive days. The tibialis anterior of the treated and untreated limbs was biopsied immediately after the final treatment. Muscle fibre diameters were measured from 1µm thick toluidine blue stained resin embedded sections using light microscopy and computerized image analysis software. Results: For treatment of the whole lower limb, the mean fibre diameter increased by 6.0% from 47.31±13.4µm(95%CI:46.47-48.16 in control biopsies to 50.14±13.93µm (95%CI:49.26-51.02 in treated muscle (p<0.001.Treatment of a single muscle showed an increase in diameter of 11.3%, from 48.21±12.68µm (95%CI:47.31-49.11 to53.63+14.29µm (95%CI:52.61-54.66 (p<0.001. Treatment of a single muscle caused significantly more oedema thantreatment of the whole limb (p<0.001. Conclusions: Repeated treatment causes skeletal muscle oedema, and this appears to be dose related. Skeletal muscleoedema after three treatments is less than after a single treatment. Further studies on the use of compressed air massage on injured muscle are warranted.

  12. A Novel Hybrid-Fuel Storage System of Compressed Air Energy for China

    OpenAIRE

    Wenyi Liu; Linzhi Liu; Gang Xu; Feifei Liang; Yongping Yang; Weide Zhang; Ying Wu

    2014-01-01

    Compressed air energy storage (CAES) is a large-scale technology that provides long-duration energy storage. It is promising for balancing the large-scale penetration of intermittent and dispersed sources of power, such as wind and solar power, into electric grids. The existing CAES plants utilize natural gas (NG) as fuel. However, China is rich in coal but is deficient in NG; therefore, a hybrid-fuel CAES is proposed and analyzed in this study. Based on the existing CAES plants, the hybrid-f...

  13. Integrated LTCC Pressure/Flow/Temperature Multisensor for Compressed Air Diagnostics†

    Science.gov (United States)

    Fournier, Yannick; Maeder, Thomas; Boutinard-Rouelle, Grégoire; Barras, Aurélie; Craquelin, Nicolas; Ryser, Peter

    2010-01-01

    We present a multisensor designed for industrial compressed air diagnostics and combining the measurement of pressure, flow, and temperature, integrated with the corresponding signal conditioning electronics in a single low-temperature co-fired ceramic (LTCC) package. The developed sensor may be soldered onto an integrated electro-fluidic platform by using standard surface mount device (SMD) technology, e.g., as a standard electronic component would be on a printed circuit board, obviating the need for both wires and tubes and thus paving the road towards low-cost integrated electro-fluidic systems. Several performance aspects of this device are presented and discussed, together with electronics design issues. PMID:22163518

  14. Integrated LTCC pressure/flow/temperature multisensor for compressed air diagnostics.

    Science.gov (United States)

    Fournier, Yannick; Maeder, Thomas; Boutinard-Rouelle, Grégoire; Barras, Aurélie; Craquelin, Nicolas; Ryser, Peter

    2010-01-01

    We present a multisensor designed for industrial compressed air diagnostics and combining the measurement of pressure, flow, and temperature, integrated with the corresponding signal conditioning electronics in a single low-temperature co-fired ceramic (LTCC) package. The developed sensor may be soldered onto an integrated electro-fluidic platform by using standard surface mount device (SMD) technology, e.g., as a standard electronic component would be on a printed circuit board, obviating the need for both wires and tubes and thus paving the road towards low-cost integrated electro-fluidic systems. Several performance aspects of this device are presented and discussed, together with electronics design issues.

  15. Geotechnical issues and guidelines for storage of compressed air in excavated hard rock caverns

    Energy Technology Data Exchange (ETDEWEB)

    Allen, R.D.; Doherty, T.J.; Fossum, A.F.

    1982-04-01

    The results of a literature survey on the stability of excavated hard rock caverns are presented. The objective of the study was to develop geotechnical criteria for the design of compressed air energy storage (CAES) caverns in hard rock formations. These criteria involve geologic, hydrological, geochemical, geothermal, and in situ stress state characteristics of generic rock masses. Their relevance to CAES caverns, and the identification of required research areas, are identified throughout the text. This literature survey and analysis strongly suggests that the chief geotechnical issues for the development and operation of CAES caverns in hard rock are impermeability for containment, stability for sound openings, and hydrostatic balance.

  16. The Fracture Influence on the Energy Loss of Compressed Air Energy Storage in Hard Rock

    Directory of Open Access Journals (Sweden)

    Hehua Zhu

    2015-01-01

    Full Text Available A coupled nonisothermal gas flow and geomechanical numerical modeling is conducted to study the influence of fractures (joints on the complex thermohydromechanical (THM performance of underground compressed air energy storage (CAES in hard rock caverns. The air-filled chamber is modeled as porous media with high porosity, high permeability, and high thermal conductivity. The present analysis focuses on the CAES in hard rock caverns at relatively shallow depth, that is, ≤100 m, and the pressure in carven is significantly higher than ambient pore pressure. The influence of one discrete crack and multiple crackson energy loss analysis of cavern in hard rock media are carried out. Two conditions are considered during each storage and release cycle, namely, gas injection and production mass being equal and additional gas injection supplemented after each cycle. The influence of the crack location, the crack length, and the crack open width on the energy loss is studied.

  17. A Novel Pumped Hydro Combined with Compressed Air Energy Storage System

    Directory of Open Access Journals (Sweden)

    Erren Yao

    2013-03-01

    Full Text Available A novel pumped hydro combined with compressed air energy storage (PHCA system is proposed in this paper to resolve the problems of bulk energy storage in the wind power generation industry over an area in China, which is characterised by drought and water shortages. Thermodynamic analysis of the energy storage system, which focuses on the pre-set pressure, storage volume capacity, water air volume ratio, pump performance, and water turbine performance of the storage system, is also presented. This paper discovers how such parameters affect the performance of the whole system. The ideal performance of this novel system has the following advantages: a simple, highly effective and low cost structure, which is comparable to the efficiency of a traditional pumped hydro storage system. Research results show a great solution to the current storage constraints encountered in the development of the wind power industry in China, which have been widely recognised as a bottleneck in the wind energy storage industry.

  18. The Use of Compressed Air for Micro-Jet Cooling After MIG Welding

    Directory of Open Access Journals (Sweden)

    Hadryś D.

    2016-09-01

    Full Text Available The material selected for this investigation was low alloy steel weld metal deposit (WMD after MIG welding with micro-jet cooling. The present investigation was aimed as the following tasks: obtained WMD with various amount of acicular ferrite and further analyze impact toughness of WMD in terms of acicular ferrite amount in it. Weld metal deposit (WMD was first time carried out for MIG welding with micro-jet cooling of compressed air and gas mixture of argon and air. Until that moment only argon, helium and nitrogen were tested as micro-jet gases for MIG/MAG processes. An important role in the interpretation of the results can give methods of artificial intelligence.

  19. Economic Analysis of using Above Ground Gas Storage Devices for Compressed Air Energy Storage System

    Institute of Scientific and Technical Information of China (English)

    LIU Jinchao; ZHANG Xinjing; XU Yujie; CHEN Zongyan; CHEN Haisheng; TAN Chunqing

    2014-01-01

    Above ground gas storage devices for compressed air energy storage (CAES) have three types:air storage tanks,gas cylinders,and gas storage pipelines.A cost model of these gas storage devices is established on the basis of whole life cycle cost (LCC) analysis.The optimum parameters of the three types are determined by calculating the theoretical metallic raw material consumption of these three devices and considering the difficulties in manufacture and the influence of gas storage device number.The LCCs of the three types are comprehensively analyzed and compared.The result reveal that the cost of the gas storage pipeline type is lower than that of the other two types.This study may serve as a reference for designing large-scale CAES systems.

  20. A Novel Constant-Pressure Pumped Hydro Combined with Compressed Air Energy Storage System

    Directory of Open Access Journals (Sweden)

    Erren Yao

    2014-12-01

    Full Text Available As intermittent renewable energy is receiving increasing attention, the combination of intermittent renewable energy with large-scale energy storage technology is considered as an important technological approach for the wider application of wind power and solar energy. Pumped hydro combined with compressed air energy storage system (PHCA is one of the energy storage systems that not only integrates the advantages but also overcomes the disadvantages of compressed air energy storage (CAES systems and pumped hydro energy storage systems to solve the problem of energy storage in China’s arid regions. Aiming at the variable working conditions of PHCA system technology, this study proposes a new constant-pressure PHCA. The most significant characteristics of this system were that the water pump and hydroturbine work under stable conditions and this improves the working efficiency of the equipment without incurring an energy loss. In addition, the constant-pressure PHCA system was subjected to energy and exergy analysis, in expectation of exploring an attractive solution for the large-scale storage of existing intermittent renewable energy.

  1. Potential and Evolution of Compressed Air Energy Storage: Energy and Exergy Analyses

    Directory of Open Access Journals (Sweden)

    Young-Min Kim

    2012-08-01

    Full Text Available Energy storage systems are increasingly gaining importance with regard to their role in achieving load levelling, especially for matching intermittent sources of renewable energy with customer demand, as well as for storing excess nuclear or thermal power during the daily cycle. Compressed air energy storage (CAES, with its high reliability, economic feasibility, and low environmental impact, is a promising method for large-scale energy storage. Although there are only two large-scale CAES plants in existence, recently, a number of CAES projects have been initiated around the world, and some innovative concepts of CAES have been proposed. Existing CAES plants have some disadvantages such as energy loss due to dissipation of heat of compression, use of fossil fuels, and dependence on geological formations. This paper reviews the main drawbacks of the existing CAES systems and presents some innovative concepts of CAES, such as adiabatic CAES, isothermal CAES, micro-CAES combined with air-cycle heating and cooling, and constant-pressure CAES combined with pumped hydro storage that can address such problems and widen the scope of CAES applications, by energy and exergy analyses. These analyses greatly help us to understand the characteristics of each CAES system and compare different CAES systems.

  2. Analysis and Optimization of a Compressed Air Energy Storage—Combined Cycle System

    Directory of Open Access Journals (Sweden)

    Wenyi Liu

    2014-06-01

    Full Text Available Compressed air energy storage (CAES is a commercial, utility-scale technology that provides long-duration energy storage with fast ramp rates and good part-load operation. It is a promising storage technology for balancing the large-scale penetration of renewable energies, such as wind and solar power, into electric grids. This study proposes a CAES-CC system, which is based on a conventional CAES combined with a steam turbine cycle by waste heat boiler. Simulation and thermodynamic analysis are carried out on the proposed CAES-CC system. The electricity and heating rates of the proposed CAES-CC system are lower than those of the conventional CAES by 0.127 kWh/kWh and 0.338 kWh/kWh, respectively, because the CAES-CC system recycles high-temperature turbine-exhausting air. The overall efficiency of the CAES-CC system is improved by approximately 10% compared with that of the conventional CAES. In the CAES-CC system, compressing intercooler heat can keep the steam turbine on hot standby, thus improving the flexibility of CAES-CC. This study brought about a new method for improving the efficiency of CAES and provided new thoughts for integrating CAES with other electricity-generating modes.

  3. A Novel Hybrid-Fuel Storage System of Compressed Air Energy for China

    Directory of Open Access Journals (Sweden)

    Wenyi Liu

    2014-08-01

    Full Text Available Compressed air energy storage (CAES is a large-scale technology that provides long-duration energy storage. It is promising for balancing the large-scale penetration of intermittent and dispersed sources of power, such as wind and solar power, into electric grids. The existing CAES plants utilize natural gas (NG as fuel. However, China is rich in coal but is deficient in NG; therefore, a hybrid-fuel CAES is proposed and analyzed in this study. Based on the existing CAES plants, the hybrid-fuel CAES incorporates an external combustion heater into the power generation subsystem to heat the air from the recuperator and the air from the high-pressure air turbine. Coal is the fuel for the external combustion heater. The overall efficiency and exergy efficiency of the hybrid-fuel CAES are 61.18% and 59.84%, respectively. Given the same parameters, the cost of electricity (COE of the hybrid-fuel CAES, which requires less NG, is $5.48/MW∙h less than that of the gas-fuel CAES. Although the proposed CAES requires a relatively high investment in the current electricity system in North China, the proposed CAES will be likely to become competitive in the market, provided that the energy supplies are improved and the large scale grid-connection of wind power is realized.

  4. Numerical Study of Water Production from Compressible Moist-Air Flow

    Directory of Open Access Journals (Sweden)

    sabah hamidi

    2016-01-01

    Full Text Available In this research a numerical study of water production from compressible moist-air flow by condensing of the vapor component of the atmospheric air through a converging-diverging nozzle is performed. The atmospheric air can be sucked by a vacuum compressor. The geographical conditions represent a hot and humid region, for example Bandar Abbas, Iran, with coordinates, 270 11 ’ N and 560 16’ E and summer climate conditions of about 40℃and relative humidity above 80%. Parametric studies are performed for the atmospheric-air temperature between, 40℃ to 50℃, and relative humidity between49.6% to 100.%. For these ranges of operating conditions and a nozzle with the area ratio of 1.17, the liquid mass flow rates falls in the range 0.272 to 0.376 kg/s. The results show that, the energy consumed by the compressor for production 1 kg of water will be 1.279 kWh. The price of 1 kWh is 372 Rials, therefore the price for the production of 1 kg liquid water will be 475.8 Rials, therefore, the scheme is economically suitable.

  5. Air quality assessment of low emission zones in Copenhagen. [Denmark]; Luftkvalitetsvurdering af ren-luftzone i Koebenhavn

    Energy Technology Data Exchange (ETDEWEB)

    Solvang Jensen, S.; Ketzel, M.; Brandt, J.; Winther, M.; Ellermann, T.

    2012-09-15

    According to the government agreement from 2011 improved low emission zones have been identified as a measure to improve the air quality in greater Danish cities, and to ensure compliance with air quality limit values for NO{sub 2} of 40 {mu}g/m{sup 3} as an annual mean. The limit value is violated at H.C. Andersens Boulevard in Copenhagen which is one of the busiest urban streets in Denmark and a fixed air quality monitor station is also located in the street. Air quality model calculations also shows that some other busy streets in Copenhagen violate the annual air quality limit values for NO{sub 2}. The objective of the project is to assess the impacts of a number of improved low emission zone measures in Copenhagen regarding emissions and air quality with focus on NO{sub 2}. The impact assessment of different scenarios includes assessment of emissions and air quality. The assessment is carried out in great details for NO{sub 2} and to a lesser degree for PM exhaust, PM{sub 2.5} and PM{sub 10}. Since air quality assessment is resource demanding only the main scenarios are carried out with the full air quality model whereas the air quality of the scenario variants are assessed based on regression analysis between emissions and air quality in scenarios calculated with the full air quality model. (LN)

  6. Preliminary formation analysis for compressed air energy storage in depleted natural gas reservoirs :

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, William Payton

    2013-06-01

    The purpose of this study is to develop an engineering and operational understanding of CAES performance for a depleted natural gas reservoir by evaluation of relative permeability effects of air, water and natural gas in depleted natural gas reservoirs as a reservoir is initially depleted, an air bubble is created, and as air is initially cycled. The composition of produced gases will be evaluated as the three phase flow of methane, nitrogen and brine are modeled. The effects of a methane gas phase on the relative permeability of air in a formation are investigated and the composition of the produced fluid, which consists primarily of the amount of natural gas in the produced air are determined. Simulations of compressed air energy storage (CAES) in depleted natural gas reservoirs were carried out to assess the effect of formation permeability on the design of a simple CAES system. The injection of N2 (as a proxy to air), and the extraction of the resulting gas mixture in a depleted natural gas reservoir were modeled using the TOUGH2 reservoir simulator with the EOS7c equation of state. The optimal borehole spacing was determined as a function of the formation scale intrinsic permeability. Natural gas reservoir results are similar to those for an aquifer. Borehole spacing is dependent upon the intrinsic permeability of the formation. Higher permeability allows increased injection and extraction rates which is equivalent to more power per borehole for a given screen length. The number of boreholes per 100 MW for a given intrinsic permeability in a depleted natural gas reservoir is essentially identical to that determined for a simple aquifer of identical properties. During bubble formation methane is displaced and a sharp N2methane boundary is formed with an almost pure N2 gas phase in the bubble near the borehole. During cycling mixing of methane and air occurs along the boundary as the air bubble boundary moves. The extracted gas mixture changes as a

  7. Experimental investigation on a solid desiccant system integrated with a R407C compression air conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Fatouh, M.; Mostafa, A. [Dept. of Mechanical Power Engineering, Faculty of Engineering, El-Mattaria (Helwan Univ.), Masaken El-Helmia P.O., Cairo 11718 (Egypt); Ibrahim, Talaat A. [Dept. of Mechanical Power Engineering, Faculty of Engineering, El-Mattaria (Helwan Univ.), Masaken El-Helmia P.O., Cairo 11718 (Egypt); King Saud Univ., P.O. 70908, 11577 Riyadh (Saudi Arabia)

    2009-10-15

    In the present work, experimental performance data of a solid desiccant based hybrid air conditioning system are presented. The system consists of a packed bed solid desiccant integrated with a R407C conventional vapor compression refrigeration system. Experiments are carried out during dehumidification operation mode for various operating parameters such as; desiccant mass on shelves (5, 10 and 15 kg), air mass flow rate (7.4 and 10.2 kg/min), shelves number (1, 2 and 3) and three values of shelves span (7, 14 and 28 cm) at evaporator air inlet conditions of 28 C DBT and 66% RH, condenser air inlet volume flow rate of 850 m{sup 3}/h and temperature of 35 C. The reactivation of the desiccant at different regeneration temperatures and air flow rates as well as desiccant masses is also investigated. During the dehumidification mode, the average system coefficient of performance increases by 6.2% and 1.61% when the mass of desiccant increases from 5 to 10 kg and from 10 to 15 kg, respectively. The enhancement in the coefficient of performance is 6.2% due to increasing the air mass flow rate from 7.4 to 10.2 kg/min. Increasing both shelves number and span yields to a reduction in the adsorption rate that can be extracted by the desiccant material in the ranges of considered operating conditions. The regeneration temperature and the air flow rate of regeneration have significant effects on the reactivation process. It was found that, with increasing the mass flow rate of regenerated air from 7.4 to 10.2 kg/min produces a reduction in regeneration time by 87.5% and an augmentation in the desorption rate by 16% after 10 min of regeneration. In addition, with escalating the regeneration temperature from 45 to 55 C, the reactivation time reduces by 25%. Reported results revealed that solid desiccant based hybrid air conditioning system reduces the compressor electric power and the number of electric unit (kW h) by 10.2%. (author)

  8. Swiss Compressed Air - Development of instruments for the 2005 - 2008 campaign; Druckluft Schweiz. Instrumentenentwicklung fuer die Kampagne 2005-2008

    Energy Technology Data Exchange (ETDEWEB)

    Radgen, P. [Fraunhofer-Institut fuer System- und Innovationsforschung (ISI), Karlsruhe (Germany); Jochem, E. [Swiss Federal Institute of Technology (ETH), Centre for Energy Policy and Economics (CEPE), Zuerich (Switzerland)

    2007-01-15

    This final report for the Swiss Federal Office of Energy (SFOE) takes a look at the development of a programme concerning the optimisation of compressed-air installations in Switzerland. The programme, which is to run from 2005 to 2008, aims to support operators of compressed-air equipment in the optimisation of their installations. The work to be done in co-operation with research institutes, manufacturers and a marketing company is reviewed. A series of tools is described which was developed during 2005 and 2006 to help systems' operators analyse and optimise their compressed air systems. As well as guidelines on optimisation, modernisation and new construction, an Internet-based benchmarking system and tools for heat recovery, leaks, the correct dimensioning of pipes and condensate drains. were developed. The report describes these tools and presents documentation on the subject, including screen-shots of the Internet platform.

  9. Stability and design criteria studies for compressed air energy storage reservoirs. Progress report, FY 1977.

    Energy Technology Data Exchange (ETDEWEB)

    Smith, G.C.; Stottlemyre, J.A.; Wiles, L.E.; Loscutoff, W.V.; Pincus, H.J.

    1978-03-01

    Progress made during FY-1977 in establishing design criteria to ensure the successful operation and long-term stability of Compressed Air Energy Storage (CAES) reservoirs in underground porous media, such as aquifers is summarized. The formulation of pertinent criteria is important since the long-term stability of air storage reservoirs is probably the item of greatest risk to the successful demonstration and commercialization of the CAES concept. The study has been divided into four phases: (1) state-of-the-art survey, (2) analytical modeling studies, (3) laboratory studies, and (4) field testing. The first of these phases, the state-of-the-art survey for air storage in porous reservoirs, has been completed on schedule and is reported in Section 2. Sections 3 and 4 are progress reports on Phases 2 and 3. No work has been done on Phase 4. It is planned that the field testing phase of this study will be carried out in conjunction with the Department of Energy/Electric Power Research Institute (DOE/EPRI) CAES Demonstration Program. This phase is not scheduled to begin until FY-1979.

  10. Roles of nitrogen, oxygen, and carbon dioxide in compressed-air narcosis.

    Science.gov (United States)

    Hesser, C M; Fagraeus, L; Adolfson, J

    1978-12-01

    In an attempt to determine the roles of nitrogen, oxygen, and carbon dioxide in compressed-air narcosis, the effects on performance (mental function and manual dexterity) of adding CO2 in various concentrations to the inspired gas under three different conditions were studied in eight healthy male volunteers. The three conditions were: (1) air breathing at 1.3 ATA; (2) oxygen breathing at 1.7 ATA; and (3) air breathing at 8.0 ATA (same inspired O2 pressure as in (2)). By relating performance to the changes induced in end-tidal (alveolar) gas pressures, and comparing the data from the three conditions, we arrived at the following results and conclusions. A rise in O2 pressure to 1.65 ATA, or in N2 pressure to 6.3 ATA at a constant high PO2 level, caused a significant decrement of 10% in mental function but no consistent effect on psychomotor function. A rise in end-tidal PCO2 of 10 mmHg caused an impairment of approximately 10% in both mental and psychomotor functions. The results suggest that, at raised partial pressures, all three gases have narcotic properties, and that the mechanism of CO2 narcosis differs fundamentally from that of N2 and O2 narcosis.

  11. Technical and economic assessment of fluidized bed augmented compressed air energy storage system. Volume III. Preconceptual design

    Energy Technology Data Exchange (ETDEWEB)

    Giramonti, A.J.; Lessard, R.D.; Merrick, D.; Hobson, M.J.

    1981-09-01

    A technical and economic assessment of fluidized bed combustion augmented compressed air energy storage systems is presented. The results of this assessment effort are presented in three volumes. Volume III - Preconceptual Design contains the system analysis which led to the identification of a preferred component configuration for a fluidized bed combustion augmented compressed air energy storage system, the results of the effort which transformed the preferred configuration into preconceptual power plant design, and an introductory evaluation of the performance of the power plant system during part-load operation and while load following.

  12. Isobar gas and steam. Compressed air storage plant with heat storage; Isobares GuD. Druckluftspeicherkraftwrk mit Waermespeicher

    Energy Technology Data Exchange (ETDEWEB)

    Schlitzberger, Christian; Leithner, Reinhard; Nielsen, Lasse [Technische Univ. Braunschweig (Germany). Inst. fuer Waerme- und Brennstofftechnik

    2008-07-01

    Due to the worldwide increasing energy consumption the unfavourable aspects of the today's power supply structure are strengthened continuously. There are two compressed air energy storage power stations existing. However, these power stations exhibit worse efficiencies of storage in comparison to existing pumped-storage power plants. In order to avoid this disadvantage, a concept of a isobaric gas and steam compressed air storage plant was developed at the institute for heat and fuel technology at the technical university of Braunschweig. This concept is presented in the contribution under consideration.

  13. Modeling of coupled thermodynamic and geomechanical performance of underground compressed air energy storage (CAES) in lined rock caverns

    Energy Technology Data Exchange (ETDEWEB)

    Rutqvist, J.; Kim, H. -M.; Ryu, D. -W.; Synn, J. -H.; Song, W. -K.

    2012-02-01

    We applied coupled nonisothermal, multiphase fluid flow and geomechanical numerical modeling to study the coupled thermodynamic and geomechanical performance of underground compressed air energy storage (CAES) in concrete-lined rock caverns. The paper focuses on CAES in lined caverns at relatively shallow depth (e.g., 100 m depth) in which a typical CAES operational pressure of 5 to 8 MPa is significantly higher than both ambient fluid pressure and in situ stress. We simulated a storage operation that included cyclic compression and decompression of air in the cavern, and investigated how pressure, temperature and stress evolve over several months of operation. We analyzed two different lining options, both with a 50 cm thick low permeability concrete lining, but in one case with an internal synthetic seal such as steel or rubber. For our simulated CAES system, the thermodynamic analysis showed that 96.7% of the energy injected during compression could be recovered during subsequent decompression, while 3.3% of the energy was lost by heat conduction to the surrounding media. Our geomechanical analysis showed that tensile effective stresses as high as 8 MPa could develop in the lining as a result of the air pressure exerted on the inner surface of the lining, whereas thermal stresses were relatively smaller and compressive. With the option of an internal synthetic seal, the maximum effective tensile stress was reduced from 8 to 5 MPa, but was still in substantial tension. We performed one simulation in which the tensile tangential stresses resulted in radial cracks and air leakage though the lining. This air leakage, however, was minor (about 0.16% of the air mass loss from one daily compression) in terms of CAES operational efficiency, and did not significantly impact the overall energy balance of the system. However, despite being minor in terms of energy balance, the air leakage resulted in a distinct pressure increase in the surrounding rock that could be

  14. Acoustic localization in weakly compressible elastic media containing random air bubbles.

    Science.gov (United States)

    Liang, Bin; Cheng, Jian-chun

    2007-01-01

    We study theoretically the propagation of longitudinal wave in weakly compressible elastic media containing random air bubbles by using a self-consistent method. By inspecting the scattering cross section of an individual bubble and estimating the mean free paths of the elastic wave propagating in the bubbly weakly compressible media, the mode conversion is numerically proved negligible as the longitudinal wave is scattered by the bubbles. On the basis of the bubble dynamic equation, the wave propagation is solved rigorously with the multiple scattering effects incorporated. In a range of frequency slightly above the bubble resonance frequency, the acoustic localization in such a class of media is theoretically identified with even a very small volume fraction of bubbles. We present a method by analyzing the spatial correlation of wave field to identify the phenomenon of localization, which turns out to be effective. The sensibility of the features of localization to the structure parameters is numerically investigated. The spatial distribution of acoustic energy is also studied and the results show that the waves are trapped within a spatial domain adjacent to the source when localization occurs.

  15. Slow Dynamics Model of Compressed Air Energy Storage and Battery Storage Technologies for Automatic Generation Control

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, Venkat; Das, Trishna

    2016-05-01

    Increasing variable generation penetration and the consequent increase in short-term variability makes energy storage technologies look attractive, especially in the ancillary market for providing frequency regulation services. This paper presents slow dynamics model for compressed air energy storage and battery storage technologies that can be used in automatic generation control studies to assess the system frequency response and quantify the benefits from storage technologies in providing regulation service. The paper also represents the slow dynamics model of the power system integrated with storage technologies in a complete state space form. The storage technologies have been integrated to the IEEE 24 bus system with single area, and a comparative study of various solution strategies including transmission enhancement and combustion turbine have been performed in terms of generation cycling and frequency response performance metrics.

  16. Technology assessment report for the Soyland Power Cooperative, Inc. compressed air energy storage system (CAES)

    Science.gov (United States)

    1982-01-01

    The design and operational features of compressed air energy storage systems (CAES) in general and, specifically, of a proposed 220 MW plant being planned by the Soyland Power Cooperative, Inc., in Illinois are described. The need for peaking capacity, CAES requirements for land, fuel, water, and storage caverns, are discussed, and the costs, environmental impacts and licensing requirements of CAES are compared with those of power plants using simple cycle or combined cycle combustion turbines. It is concluded that during the initial two years of CAES operation, the CAES would cost more than a combustion turbine or combined cycle facility, but thereafter the CAES would have a increasing economic advantage. The overall environmental impact of a CAES plant is minimal, and there should be no great difficulties with CAES licensing.

  17. Thermal System Analysis and Optimization of Large-Scale Compressed Air Energy Storage (CAES

    Directory of Open Access Journals (Sweden)

    Zhongguang Fu

    2015-08-01

    Full Text Available As an important solution to issues regarding peak load and renewable energy resources on grids, large-scale compressed air energy storage (CAES power generation technology has recently become a popular research topic in the area of large-scale industrial energy storage. At present, the combination of high-expansion ratio turbines with advanced gas turbine technology is an important breakthrough in energy storage technology. In this study, a new gas turbine power generation system is coupled with current CAES technology. Moreover, a thermodynamic cycle system is optimized by calculating for the parameters of a thermodynamic system. Results show that the thermal efficiency of the new system increases by at least 5% over that of the existing system.

  18. Experimental study on fire extinguishing with a newly prepared multi-component compressed air foam

    Institute of Scientific and Technical Information of China (English)

    WANG XiShi; LIAO YaoJian; LIN Lin

    2009-01-01

    A multi-component compressed air foam system (MCAFS) was developed with newly prepared multi-component foaming agents. Extinguishing of wood crib and oil pool fires was performed under different conditions, such as foam concentration, mixing chamber forepart structure and working pressure. It was found that the foam concentration had sufficient effects on fire extinguishing efficiency, and an optimized concentration value exists. For instance, for diesel oil pool fires, this value is about 2.2% while it is about 4.0% for wood crib fires. The results also show that the system with a coaxial mixing chamber has greater efficiency than a T-shape. The effects of working pressure on fire extin-guishing are evident in experiments, i.e., the higher the working pressure is, the more readily the fire is extinguished.

  19. Compressed Air Energy Storage System Control and Performance Assessment Using Energy Harvested Index

    Directory of Open Access Journals (Sweden)

    Hanif SedighNejad

    2014-01-01

    Full Text Available In this paper a new concept for control and performance assessment of compressed air energy storage (CAES systems in a hybrid energy system is introduced. The proposed criterion, based on the concept of energy harvest index (HEI, measures the capability of a storage system to capture renewable energy. The overall efficiency of the CAES system and optimum control and design from the technical and economic point of view is presented. A possible application of this idea is an isolated community with significant wind energy resource. A case study reveals the usefulness of the proposed criterion in design, control and implementation of a small CAES system in a hybrid power system (HPM for an isolated community. Energy harvested index and its effectiveness in increasing the wind penetration rate in the total energy production is discussed.

  20. Compressed air energy storage system reservoir size for a wind energy baseload power plant

    Energy Technology Data Exchange (ETDEWEB)

    Cavallo, A.J.

    1996-12-31

    Wind generated electricity can be transformed from an intermittent to a baseload resource using an oversized wind farm in conjunction with a compressed air energy storage (CAES) system. The size of the storage reservoir for the CAES system (solution mined salt cavern or porous media) as a function of the wind speed autocorrelation time (C) has been examined using a Monte Carlo simulation for a wind class 4 (wind power density 450 W m{sup -2} at 50 m hub height) wind regime with a Weibull k factor of 2.5. For values of C typically found for winds over the US Great Plains, the storage reservoir must have a 60 to 80 hour capacity. Since underground reservoirs account for only a small fraction of total system cost, this larger storage reservoir has a negligible effect on the cost of energy from the wind energy baseload system. 7 refs., 2 figs., 1 tab.

  1. Integrated LTCC Pressure/Flow/Temperature Multisensor for Compressed Air Diagnostics†

    Directory of Open Access Journals (Sweden)

    Nicolas Craquelin

    2010-12-01

    Full Text Available We present a multisensor designed for industrial compressed air diagnostics and combining the measurement of pressure, flow, and temperature, integrated with the corresponding signal conditioning electronics in a single low-temperature co-fired ceramic (LTCC package. The developed sensor may be soldered onto an integrated electro-fluidic platform by using standard surface mount device (SMD technology, e.g., as a standard electronic component would be on a printed circuit board, obviating the need for both wires and tubes and thus paving the road towards low-cost integrated electro-fluidic systems. Several performance aspects of this device are presented and discussed, together with electronics design issues.

  2. A Feasibility Study on Operating Large Scale Compressed Air Energy Storage in Porous Formations

    Science.gov (United States)

    Wang, B.; Pfeiffer, W. T.; Li, D.; Bauer, S.

    2015-12-01

    Compressed air energy storage (CAES) in porous formations has been considered as one promising option of large scale energy storage for decades. This study, hereby, aims at analyzing the feasibility of operating large scale CAES in porous formations and evaluating the performance of underground porous gas reservoirs. To address these issues quantitatively, a hypothetic CAES scenario with a typical anticline structure in northern Germany was numerically simulated. Because of the rapid growth in photovoltaics, the period of extraction in a daily cycle was set to the early morning and the late afternoon in order to bypass the massive solar energy production around noon. The gas turbine scenario was defined referring to the specifications of the Huntorf CAES power plant. The numerical simulations involved two stages, i.e. initial fill and cyclic operation, and both were carried out using the Eclipse E300 simulator (Schlumberger). Pressure loss in the gas wells was post analyzed using an analytical solution. The exergy concept was applied to evaluate the potential energy amount stored in the specific porous formation. The simulation results show that porous formations prove to be a feasible solution of large scale CAES. The initial fill with shut-in periods determines the spatial distribution of the gas phase and helps to achieve higher gas saturation around the wells, and thus higher deliverability. The performance evaluation shows that the overall exergy flow of stored compressed air is also determined by the permeability, which directly affects the deliverability of the gas reservoir and thus the number of wells required.

  3. Feasibility study of porous media compressed air energy storage in South Carolina, United States of America

    Science.gov (United States)

    Jarvis, Alexandra-Selene

    Renewable Energy Systems (RES) such as solar and wind, are expected to play a progressively significant role in electricity production as the world begins to move away from an almost total reliance on nonrenewable sources of power. In the US there is increasing investment in RES as the Department of Energy (DOE) expands its wind power network to encompass the use of offshore wind resources in places such as the South Carolina (SC) Atlantic Coastal Plain. Because of their unstable nature, RES cannot be used as reliable grid-scale power sources unless power is somehow stored during excess production and recovered at times of insufficiency. Only two technologies have been cited as capable of storing renewable energy at this scale: Pumped Hydro Storage and Compressed Air Energy Storage (CAES). Both CAES power plants in existence today use solution-mined caverns as their storage spaces. This project focuses on exploring the feasibility of employing the CAES method to store excess wind energy in sand aquifers. The numerical multiphase flow code, TOUGH2, was used to build models that approximate subsurface sand formations similar to those found in SC. Although the aquifers of SC have very low dips, less than 10, the aquifers in this study were modeled as flat, or having dips of 00. Cycle efficiency is defined here as the amount of energy recovered compared to the amount of energy injected. Both 2D and 3D simulations have shown that the greatest control on cycle efficiency is the volume of air that can be recovered from the aquifer after injection. Results from 2D simulations showed that using a dual daily peak load schedule instead of a single daily peak load schedule increased cycle efficiency as do the following parameters: increased anisotropy, screening the well in the upper portions of the aquifer, reduced aquifer thickness, and an initial water displacement by the continuous injection of air for at least 60 days. Aquifer permeability of 1x10-12 m2 produced a cycle

  4. Bitburg Air Base, West Germany. Revised Uniform Summary of Surface Weather Observations (RUSSWO). Parts A-F.

    Science.gov (United States)

    1982-06-29

    UNIT NUMBERS Air Force Environmental Technical Apple Center Scott AFB IL 62225 It. SWOt ~ t g Ws ~g FICE NAME AND ADORESS IS REPORT DATE AiU ete evc MC...forms or from automated data collections for all Air Force operated stations. For those stations observing less than 24 hours per day, and where maxi ...for any column. Two tables of daily extremes are prepared: a. Exree maxi temperature E b. Extreme minimum temperature NOTE: The following symbols are

  5. Performance Analysis of a Coal-Fired External Combustion Compressed Air Energy Storage System

    Directory of Open Access Journals (Sweden)

    Wenyi Liu

    2014-11-01

    Full Text Available Compressed air energy storage (CAES is one of the large-scale energy storage technologies utilized to provide effective power peak load shaving. In this paper, a coal-fired external combustion CAES, which only uses coal as fuel, is proposed. Unlike the traditional CAES, the combustion chamber is substituted with an external combustion heater in which high-pressure air is heated before entering turbines to expand in the proposed system. A thermodynamic analysis of the proposed CAES is conducted on the basis of the process simulation. The overall efficiency and the efficiency of electricity storage are 48.37% and 81.50%, respectively. Furthermore, the exergy analysis is then derived and forecasted, and the exergy efficiency of the proposed system is 47.22%. The results show that the proposed CAES has more performance advantages than Huntorf CAES (the first CAES plant in the world. Techno-economic analysis of the coal-fired CAES shows that the cost of electricity (COE is $106.33/MWh, which is relatively high in the rapidly developing power market. However, CAES will be more likely to be competitive if the power grid is improved and suitable geographical conditions for storage caverns are satisfied. This research provides a new approach for developing CAES in China.

  6. Geochemical effects of compressed air, methane, or hydrogen intrusion into shallow aquifers

    Science.gov (United States)

    Berta, Marton; Dethlefsen, Frank; Ebert, Markus; Dahmke, Andreas

    2016-04-01

    The fluctuating energy yield of renewable sources, most importantly wind and solar, implies the emerging necessity of energy storage. Already operating possibilities for geological energy storage include storage of compressed air (CAES), methane, and hydrogen. For the safe and sustainable implementation of subsurface energy storage, site specific risk assessment studies and elaborated monitoring strategies are needed, based on proper process understanding. In case of gas storage, this process understanding must include gas-specific reactions to be expected in shallow aquifers following a leakage of compressed air, methane, or hydrogen, and therefore potentially changing the composition of the groundwater, which is protected by law. As the geochemical reactions potentially following gas leakages were not known in a sufficient extent, experiments representing relevant hydrogeological conditions were carried out. The experimental approach included batch and column experiments using mainly sediment from a shallow Pleistocene aquifer percolated by the groundwater from the same aquifer. This water was saturated with the respective gas to simulate a leakage environment in a shallow aquifer. Leakage of compressed air resulted in pyrite oxidation (rates up to 4 μM/h). In our experimental conditions with oxygen partial pressures between 0 and 11 bars pyrite oxidation caused minor (up to 0.5 mM) increase in sulfate concentration and minor (up to 0.5) decrease in pH. The transfer function on reaction kinetics developed using PHREEQC based on the experimental reaction rates for upscaling the results includes a passivation inhibiting more than 90% of the pyrite reactivity. Methane oxidation coupled to reduction of nitrate, and especially sulfate is known from various groundwater and marine environments. However, fugitive methane does not cause detectable changes in groundwater within one year in our experiments. This acknowledges earlier field studies describing no methane

  7. Restaurering af Skjern Å

    DEFF Research Database (Denmark)

    Jessen, K.; Boysen Larsen, B.; Bundgaard, P.;

    Denne rapport indeholder resultaterne af den natur- og miljøovervågning, der blev iværksat som en del af naturgenopretningen af Skjern Å 1999-2002. Ved projektet ophørte den kunstige afvanding af den vestlige del af Skjern Å dalen. Størstedelen af de dyrkede arealer ændredes til ekstensive græsni...

  8. Exploring the concept of compressed air energy storage (CAES) in lined rock caverns at shallow depth: A modeling study of air tightness and energy balance

    Energy Technology Data Exchange (ETDEWEB)

    Kim, H.-M.; Rutqvist, J.; Ryu, D.-W.; Choi, B.-H.; Sunwoo, C.; Song, W.-K.

    2011-07-15

    This paper presents a numerical modeling study of coupled thermodynamic, multiphase fluid flow and heat transport associated with underground compressed air energy storage (CAES) in lined rock caverns. Specifically, we explored the concept of using concrete lined caverns at a relatively shallow depth for which constructing and operational costs may be reduced if air tightness and stability can be assured. Our analysis showed that the key parameter to assure long-term air tightness in such a system was the permeability of both the concrete lining and the surrounding rock. The analysis also indicated that a concrete lining with a permeability of less than 1×10{sup -18} m{sup 2} would result in an acceptable air leakage rate of less than 1%, with the operational pressure range between 5 and 8 MPa at a depth of 100 m. It was further noted that capillary retention properties and the initial liquid saturation of the lining were very important. Indeed, air leakage could be effectively prevented when the air-entry pressure of the concrete lining is higher than the operational air pressure and when the lining is kept moist at a relatively high liquid saturation. Our subsequent energy-balance analysis demonstrated that the energy loss for a daily compression and decompression cycle is governed by the air-pressure loss, as well as heat loss by conduction to the concrete liner and surrounding rock. For a sufficiently tight system, i.e., for a concrete permeability off less than 1×10{sup -18} m{sup 2}, heat loss by heat conduction tends to become proportionally more important. However, the energy loss by heat conduction can be minimized by keeping the air-injection temperature of compressed air closer to the ambient temperature of the underground storage cavern. In such a case, almost all the heat loss during compression is gained back during subsequent decompression. Finally, our numerical simulation study showed that CAES in shallow rock caverns is feasible from a leakage

  9. Experimental Results Obtained with Air Liquide Cold Compression System: CERN LHC and SNS Projects

    Science.gov (United States)

    Delcayre, F.; Courty, J.-C.; Hamber, F.; Hilbert, B.; Monneret, E.; Toia, J.-L.

    2006-04-01

    Large scale collider facilities will make intensive use of superconducting magnets, operating below 2.0 K. This dictates high-capacity refrigeration systems operating below 2.0 K. These systems, making use of cryogenic centrifugal compressors in a series arrangement with room temperature screw compressors will be coupled to a refrigerator, providing a certain power at 4.5 K. A first Air Liquide Cold Compression System (CCS) unit was built and delivered to CERN in 2001. Installed at the beginning of 2002, it was commissioned and tested successfully during year 2002. A series of four sets of identical CCS were then tested in 2004. Another set of four cryogenic centrifugal compressors (CCC) has been delivered to Thomas Jefferson National Accelerator Facility (JLAB) for the Spallation Neutron Source (SNS) in 2002. These compressors were tested and commissioned from December 2004 to July 2005. The experimental results obtained with these systems will be presented and discussed: the characteristics of the CCC will be detailed. The principles of control for the CCC in series will be detailed.

  10. Compressed air energy storage monitoring to support refrigerated mined rock cavern technology.

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Moo Yul; Bauer, Stephen J.

    2004-06-01

    This document is the final report for the Compressed Air Energy Storage Monitoring to Support Refrigerated-Mined Rock Cavern Technology (CAES Monitoring to Support RMRCT) (DE-FC26-01NT40868) project to have been conducted by CAES Development Co., along with Sandia National Laboratories. This document provides a final report covering tasks 1.0 and subtasks 2.1, 2.2, and 2.5 of task 2.0 of the Statement of Project Objectives and constitutes the final project deliverable. The proposed work was to have provided physical measurements and analyses of large-scale rock mass response to pressure cycling. The goal was to develop proof-of-concept data for a previously developed and DOE sponsored technology (RMRCT or Refrigerated-Mined Rock Cavern Technology). In the RMRCT concept, a room and pillar mine developed in rock serves as a pressure vessel. That vessel will need to contain pressure of about 1370 psi (and cycle down to 300 psi). The measurements gathered in this study would have provided a means to determine directly rock mass response during cyclic loading on the same scale, under similar pressure conditions. The CAES project has been delayed due to national economic unrest in the energy sector.

  11. Optimal Acoustic Attenuation of Weakly Compressible Media Permeated with Air Bubbles

    Institute of Scientific and Technical Information of China (English)

    LIANG Bin; CHENG Jian-Chun

    2007-01-01

    Based on fuzzy logic (FL) and genetic algorithm (GA), we present an optimization method to obtain the optimal acoustic attenuation of a longitudinal acoustic wave propagating in a weakly compressible medium permeated with air bubbles. In the optimization, the parameters of the size distribution of bubbles in the medium are optimized for providing uniformly high acoustic attenuation in the frequency band of interest. Compared with other traditional optimization methods, the unique advantage of the present method is that it can locate the global optimum quickly and effectively in need of knowing the mathematical model precisely. As illustrated by a numerical simulation, the method is effective and essential in enhancing the acoustic attenuation of such a medium in an optimal manner. The bubbly medium with optimized structural parameters can effectively attenuate longitudinal waves at intermediate frequencies with an acoustic attenuation approximating a constant value of 10(dB/cm). Such bubbly media with optimal acoustic attenuations may be applied to design acoustic absorbent by controlling broader attenuation band and higher efficiency.

  12. Internationalisering af servicedesign

    DEFF Research Database (Denmark)

    Henten, Anders

    Rapporten omhandler internationaliseringen af designvirksomhede med special fokus på servicedesign.......Rapporten omhandler internationaliseringen af designvirksomhede med special fokus på servicedesign....

  13. Compressed-air energy storage preliminary design and site development program in an aquifer. Volume 5, Part 1: Turbomachinery design

    Science.gov (United States)

    Berman, P. A.; Bonk, J. S.; Kobett, W. F.; Kosanovich, N. S.; Long, L. J.; Marinacci, D. J.

    1982-11-01

    The development of the design approach for a combustion turbine heat cycle and the major mechanical equipment for use by an electric utility at a selected aquifer air storage site is documented. A compressed air energy storage (CAES) system utilizes off peak electric power, available from base load power plants, to store compressed air underground in an aquifer. During subsequent periods, the stored air is extracted from the aquifer and used as an air supply for a generating combustion turbine expander. The aquifer has an initial discovery pressure of 840 psia. An initial air injection temperature of 1500 F was selected. The major mechanical equipment considered includes: the turbine motor/generator compressor train, intercooler and aftercooler system, and the exhaust gas regenerator. The cycle and machinery configuration and the specific mechanical equipment were selected for their Media site characteristics. These characteristics and the effect of component interdependency are considered when a conservative component design approach is established which satisfies the Media site CAES system requirements.

  14. Nonlinear compression of high energy fiber amplifier pulses in air-filled hypocycloid-core Kagome fiber.

    Science.gov (United States)

    Guichard, Florent; Giree, Achut; Zaouter, Yoann; Hanna, Marc; Machinet, Guillaume; Debord, Benoît; Gérôme, Frédéric; Dupriez, Pascal; Druon, Frédéric; Hönninger, Clemens; Mottay, Eric; Benabid, Fetah; Georges, Patrick

    2015-03-23

    We report on the generation of 34 fs and 50 µJ pulses from a high energy fiber amplifier system with nonlinear compression in an air-filled hypocycloid-core Kagome fiber. The unique properties of such fibers allow bridging the gap between solid core fibers-based and hollow capillary-based post-compression setups, thereby operating with pulse energies obtained with current state-of-the-art fiber systems. The overall transmission of the compression setup is over 70%. Together with Yb-doped fiber amplifier technologies, Kagome fibers therefore appear as a promising tool for efficient generation of pulses with durations below 50 fs, energies ranging from 10 to several hundreds of µJ, and high average powers.

  15. Air MEDEVAC in case of multiple casualties – The experience of civilian-military cooperation in RoAF

    Directory of Open Access Journals (Sweden)

    Dragoș C. Tudose

    2016-07-01

    Full Text Available Introduction: Starting September 2010 in Romania was created the Military Emergency Medical Service (SMMU by the Ministry of National Defense, which has as main mission to provide first aid and save the lives of military personnel during military operations using special equipped MEDEAVC aircraft. Nationwide exist the national emergency system which operates thru 112- SMURD acting in support of the civilian population. In case of accidents with multiple victims the experience has shown the need for collaboration between the two systems, in order to save lives. In the last 5 years there has been an increasing Airlift missions (MEDEVAC with multiple victims executed by joint civil-military medical teams using military aircraft. Material and methods. This paper provides a review of the most important aspects of particularities, advantages and disadvantages of this type of medical transport using the MEDEVAC missions based study carried out by the Air Force in recent years. Results and conclusions. Performing these tasks presents challenges to mission planning, use of medical equipment and procedures, command-control system, exercise programs jointly joint medical teams and, of course, managing a large number of patients in flight. The large number of patients transported safely and in the shortest time, regardless of weather conditions recommends this type of medical intervention. Given the Romanian military presence in various theaters and that NATO strategic medical evacuation is a national responsibility, the capacity of air transport in case multiple casualties is a priority.

  16. Baseload power production from wind turbine arrays coupled to compressed air energy storage

    Science.gov (United States)

    Succar, Samir

    An analysis is presented of compressed air energy storage (CAES) and its potential for mitigating the intermittency of wind power, facilitating access to remote wind resources and transforming wind into baseload power. Although CAES has traditionally served other grid support applications, it is also well suited for wind balancing applications due its ability to provide long duration storage, its fast ramp rates and its high part load efficiencies. In addition, geologies potentially suitable for CAES appear to be abundant in regions with high-quality wind resources. This is especially true of porous rock formations, which have the potential to be the least costly air storage option for CAES. The characteristics of formations suitable for CAES storage and the challenges associated with using air as a storage fluid are discussed. An optimization framework is developed for analyzing the cost of baseload plants comprised of wind turbine arrays backed by natural gas-fired generating capacity and/or CAES. The optimization model analyzes changes to key aspects of the system configuration such as the wind turbine rating, the relative capacities of the system components, the size of the CAES storage reservoir and the wind turbine spacing. The response of the optimal system configuration to changes in natural gas price, greenhouse gas (GHG) emissions price, capital cost, and wind resource is also considered. Wind turbine rating is given focused attention because of its substantial impact on system configuration and output behavior. The generation cost of baseload wind is compared to that of other baseload options. To highlight the carbon-mitigation potential of baseload wind, the competition with coal power (with and without CO2 capture and storage, CCS) is given prominent attention. The ability of alternative options to compete under dispatch competition is explored thereby clarifying the extent to which baseload wind can defend high capacity factors in the market. This

  17. A Study on Homogeneous Charge Compression Ignition Gasoline Engines

    Science.gov (United States)

    Kaneko, Makoto; Morikawa, Koji; Itoh, Jin; Saishu, Youhei

    A new engine concept consisting of HCCI combustion for low and midrange loads and spark ignition combustion for high loads was introduced. The timing of the intake valve closing was adjusted to alter the negative valve overlap and effective compression ratio to provide suitable HCCI conditions. The effect of mixture formation on auto-ignition was also investigated using a direct injection engine. As a result, HCCI combustion was achieved with a relatively low compression ratio when the intake air was heated by internal EGR. The resulting combustion was at a high thermal efficiency, comparable to that of modern diesel engines, and produced almost no NOx emissions or smoke. The mixture stratification increased the local A/F concentration, resulting in higher reactivity. A wide range of combustible A/F ratios was used to control the compression ignition timing. Photographs showed that the flame filled the entire chamber during combustion, reducing both emissions and fuel consumption.

  18. Thermo-Economic Comparison and Parametric Optimizations among Two Compressed Air Energy Storage System Based on Kalina Cycle and ORC

    Directory of Open Access Journals (Sweden)

    Ruixiong Li

    2016-12-01

    Full Text Available The compressed air energy storage (CAES system, considered as one method for peaking shaving and load-levelling of the electricity system, has excellent characteristics of energy storage and utilization. However, due to the waste heat existing in compressed air during the charge stage and exhaust gas during the discharge stage, the efficient operation of the conventional CAES system has been greatly restricted. The Kalina cycle (KC and organic Rankine cycle (ORC have been proven to be two worthwhile technologies to fulfill the different residual heat recovery for energy systems. To capture and reuse the waste heat from the CAES system, two systems (the CAES system combined with KC and ORC, respectively are proposed in this paper. The sensitivity analysis shows the effect of the compression ratio and the temperature of the exhaust on the system performance: the KC-CAES system can achieve more efficient operation than the ORC-CAES system under the same temperature of exhaust gas; meanwhile, the larger compression ratio can lead to the higher efficiency for the KC-CAES system than that of ORC-CAES with the constant temperature of the exhaust gas. In addition, the evolutionary multi-objective algorithm is conducted between the thermodynamic and economic performances to find the optimal parameters of the two systems. The optimum results indicate that the solutions with an exergy efficiency of around 59.74% and 53.56% are promising for KC-CAES and ORC-CAES system practical designs, respectively.

  19. Siting-selection study for the Soyland Power Cooperative, Inc. , compressed-air energy-storage system (CAES)

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    A method used for siting a compressed air energy storage (CAES) system using geotechnical and environmental criteria is explained using the siting of a proposed 220 MW water-compensated CAES plant in Illinois as an example. Information is included on the identification and comparative ranking of 28 geotechnically and environmental sites in Illinois, the examination of fatal flaws, e.g., mitigation, intensive studies, costly studies, permit denials, at 7 sites; and the selection of 3 sites for further geological surveying. (LCL)

  20. Numerical analysis of temperature and flow effects in a dry, one-dimensional aquifer used for compressed air energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Smith, G.C.; Wiles, L.E.; Loscutoff, W.V.

    1979-02-01

    A detailed description of the method of analysis and the results obtained for an investigation of the hydrodynamic and thermodynamic response of a model of a dry porous media reservoir used for compressed air energy storage (CAES) is presented. Results were obtained from a one-dimensional simulation of the cycling of heated air to and from a radial flow field surrounding a single well in a porous rock. It was assumed that the performance of the bulk of the reservoir could be characterized by the performance of a single well.

  1. Tension-Compression Fatigue of a Nextel™720/alumina Composite at 1200 °C in Air and in Steam

    Science.gov (United States)

    Lanser, R. L.; Ruggles-Wrenn, M. B.

    2016-08-01

    Tension-compression fatigue behavior of an oxide-oxide ceramic-matrix composite was investigated at 1200 °C in air and in steam. The composite is comprised of an alumina matrix reinforced with Nextel™720 alumina-mullite fibers woven in an eight harness satin weave (8HSW). The composite has no interface between the fiber and matrix, and relies on the porous matrix for flaw tolerance. Tension-compression fatigue behavior was studied for cyclical stresses ranging from 60 to 120 MPa at a frequency of 1.0 Hz. The R ratio (minimum stress to maximum stress) was -1.0. Fatigue run-out was defined as 105 cycles and was achieved at 80 MPa in air and at 70 MPa in steam. Steam reduced cyclic lives by an order of magnitude. Specimens that achieved fatigue run-out were subjected to tensile tests to failure to characterize the retained tensile properties. Specimens subjected to prior cyclic loading in air retained 100 % of their tensile strength. The steam environment severely degraded tensile properties. Tension-compression cyclic loading was considerably more damaging than tension-tension cyclic loading. Composite microstructure, as well as damage and failure mechanisms were investigated.

  2. Site specific comparison of H2, CH4 and compressed air energy storage in porous formations

    Science.gov (United States)

    Tilmann Pfeiffer, Wolf; Wang, Bo; Bauer, Sebastian

    2016-04-01

    The supply of energy from renewable sources like wind or solar power is subject to fluctuations determined by the climatic and weather conditions, and shortage periods can be expected on the order of days to weeks. Energy storage is thus required if renewable energy dominates the total energy production and has to compensate the shortages. Porous formations in the subsurface could provide large storage capacities for various energy carriers, such as hydrogen (H2), synthetic methane (CH4) or compressed air (CAES). All three energy storage options have similar requirements regarding the storage site characteristics and consequently compete for suitable subsurface structures. The aim of this work is to compare the individual storage methods for an individual storage site regarding the storage capacity as well as the achievable delivery rates. This objective is pursued using numerical simulation of the individual storage operations. In a first step, a synthetic anticline with a radius of 4 km, a drop of 900 m and a formation thickness of 20 m is used to compare the individual storage methods. The storage operations are carried out using -depending on the energy carrier- 5 to 13 wells placed in the top of the structure. A homogeneous parameter distribution is assumed with permeability, porosity and residual water saturation being 500 mD, 0.35 and 0.2, respectively. N2 is used as a cushion gas in the H2 storage simulations. In case of compressed air energy storage, a high discharge rate of 400 kg/s equating to 28.8 mio. m³/d at surface conditions is required to produce 320 MW of power. Using 13 wells the storage is capable of supplying the specified gas flow rate for a period of 31 hours. Two cases using 5 and 9 wells were simulated for both the H2 and the CH4 storage operation. The target withdrawal rates of 1 mio. sm³/d are maintained for the whole extraction period of one week in all simulations. However, the power output differs with the 5 well scenario producing

  3. Undervisning af tosprogede elever

    DEFF Research Database (Denmark)

    Horst, Christian

    2003-01-01

    Artiklen fremdrager hovedresultaterne fra Virginia P. Collier's og Wayne P. Thomas's længdeundersøgelser af tosprogede elever i USA, som formentlig er de mest omfattende undersøgelser af undervisningen af tosprogede elever overhovedet. Resultaterne diskuteres i relation til udviklingen af en...

  4. Lyden-af-Leg

    DEFF Research Database (Denmark)

    Toft, Herdis

    Præsentation af seniorforsker-projekt Lyden-af-Leg i et traderingsperspektiv og med indledende fokus på YouTube som traderings-platform.......Præsentation af seniorforsker-projekt Lyden-af-Leg i et traderingsperspektiv og med indledende fokus på YouTube som traderings-platform....

  5. Om distributionen af hvidhed

    DEFF Research Database (Denmark)

    Frello, Birgitta

    2007-01-01

    Med udgangspunkt i John Fords Western, Forfølgeren fra 1956, præsenteres en analyse af repræsentationer af race og overskridelse af raceskel, særligt i relation til konstitueringen af subjektpositioner, hvorfra spørgsmål om hvidhed og ikke-hvidhed kan afgøres....

  6. Citizen Hydrology and Compressed-Air Hydropower for Rural Electrification in Haiti

    Science.gov (United States)

    Allen, S. M.

    2015-12-01

    At the present time, only one in eight residents of Haiti has access to electricity. Two recent engineering and statistical innovations have the potential for vastly reducing the cost of installation of hydropower in Haiti and the rest of the developing world. The engineering innovation is that wind, solar and fluvial energy have been used to compress air for generation of electricity for only 20 per megawatt-hour, in contrast to the conventional World Bank practice of funding photovoltaic cells for 156 per megawatt-hour. The installation of hydropower requires a record of stream discharge, which is conventionally obtained by installing a gaging station that automatically monitors gage height (height of the water surface above a fixed datum). An empirical rating curve is then used to convert gage height to stream discharge. The multiple field measurements of gage height and discharge over a wide range of discharge values that are required to develop and maintain a rating curve require a manpower of hydrologic technicians that is prohibitive in remote and impoverished areas of the world. The statistical innovation is that machine learning has been applied to the USGS database of nearly four million simultaneous measurements of gage height and discharge to develop a new classification of rivers so that a rating curve can be developed solely from the stream slope, channel geometry, horizontal and vertical distances to the nearest upstream and downstream confluences, and two pairs of discharge - gage height measurements. The objective of this study is to organize local residents to monitor gage height at ten stream sites in the northern peninsula of Haiti over a one-year period in preparation for installation of hydropower at one of the sites. The necessary baseline discharge measurements and channel surveying are being carried out for conversion of gage height to discharge. Results will be reported at the meeting.

  7. Lyden af musik - er lyden af idealisme

    DEFF Research Database (Denmark)

    Eigtved, Michael

    2015-01-01

    Programartiklen til Det Ny Teaters opsætning af Rodgers & Hammersteins The Sound of Music, undersøger musicalgenrens - og især de konkrete ophavsmænds- affinitet til fremstillingen af såvel idealistiske som ideologiske universer.......Programartiklen til Det Ny Teaters opsætning af Rodgers & Hammersteins The Sound of Music, undersøger musicalgenrens - og især de konkrete ophavsmænds- affinitet til fremstillingen af såvel idealistiske som ideologiske universer....

  8. 应用改良AF脊柱内固定系统经皮微创内固定治疗胸腰椎压缩骨折%The Application of Improved AF Spinal Internal Fixation System With Percutaneous Minimally Invasive Internal Fixation for the Treatment of Thoracic and Lumbar Vertebral Compression Fracture

    Institute of Scientific and Technical Information of China (English)

    李晓龙; 王志军

    2015-01-01

    Objective To explore the efficacy of the AF spinal internal fixation system with percutaneous minimally invasive internal fixation for the treatment of thoracic and lumbar vertebral compression fracture. Methods Collected in our hospital 48 cases of thoracolumbar compression fractures, application of improved percutaneous minimally invasive internal fixation of AF spinal internal fixation system in the treatment of thoracolumbar compression fractures, postoperative review X-ray for curative effect analysis. Results 48 cases of compression injury vertebral height of vertebral body than preoperative obviously restoration, 90%of the average recovery to normal height of vertebral body Conclusion Application of improved percutaneous minimally invasive internal ifxation of AF spinal internal fixation system in the treatment of thoracolumbar compression fractures curative effect is distinct.%目的:探讨应用AF脊柱内固定系统经皮微创内固定治疗胸腰椎压缩骨折的疗效。方法收集本院48例胸腰椎压缩骨折,应用改良AF脊柱内固定系统经皮微创内固定治疗胸腰椎压缩骨折,术后复查X片进行疗效分析。结果48例压缩的伤椎椎体高度比术前明显得到恢复,平均恢复至正常椎体高度的90%。结论应用改良AF脊柱内固定系统经皮微创内固定治疗胸腰椎压缩骨折疗效显著。

  9. Skoling af lyst

    DEFF Research Database (Denmark)

    Bjerg, Helle

    2011-01-01

    På baggrund af interview med tre elevgenerationer fremanalyseres skolens virkningsfuldhed i skoling af lyst i et historisk perspektiv. I afhandlingen udvikles to teoretisk-analytiske optikker: Skolen som ideologisk rum - med inspiration fra Slavoj Zizeks ideologikritik, samt Skolen som affektivt...

  10. Bliv fan af AUB

    DEFF Research Database (Denmark)

    Hansen, Karsten Kryger

    2010-01-01

    Kort gennemgang af hvad det har betydet for Aalborg Universitetsbibliotek (AUB) at gå på Facebook.......Kort gennemgang af hvad det har betydet for Aalborg Universitetsbibliotek (AUB) at gå på Facebook....

  11. Storage of compressed air. A possibility for an enhanced utilization of wind energy?; Druckluftspeicherung. Ein Weg zur verstaerkten Windenergienutzung?

    Energy Technology Data Exchange (ETDEWEB)

    Kretschmer, Rutger [DREWAG - Stadtwerke Dresden GmbH, Dresden (Germany). Hauptabt. Vertrieb und Beschaffung

    2008-07-01

    The high prices for fossil energy sources are due to increasing demand, limited production quotas and exhaustion of strategically positioned deposits. Likewise the electricity prices increase to. High electricity tariffs improve the investment climate for renewable energies independently from the fuel costs. The positive development of the renewable energy is accompanied by serious disadvantages. Thus, the conditions for grid control and for the operation of fossil power stations deteriorate. The author of the contribution under consideration reports on the storage of compressed air as a possibility for the use of wind energy.

  12. Sociale konsekvenser af byfornyelsen

    DEFF Research Database (Denmark)

    Andersen, Hans Skifter; Ærø, Thorkild

    byfornyede boliger. Kun meget få flytter dog som følge af byfornyelsen, men af andre grunde. I perioden efter byfornyelsen er der imidlertid en del beboere som vælger at flytte på grund af stigende huslejer. Byfornyelsen betyder, at beboersammensætningen ændres i retning af flere i beskæftigelse med høj...

  13. En verden af medier

    DEFF Research Database (Denmark)

    Tække, Jesper

    2009-01-01

    Bogen: 'En verden af medier – Medialiseringen af politik, sprog, religion og leg' anmeldes. Anmeldelsen kan læses på: http://ojs.statsbiblioteket.dk/index.php/mediekultur/article/view/1370/1499 Udgivelsesdato: 2009......Bogen: 'En verden af medier – Medialiseringen af politik, sprog, religion og leg' anmeldes. Anmeldelsen kan læses på: http://ojs.statsbiblioteket.dk/index.php/mediekultur/article/view/1370/1499 Udgivelsesdato: 2009...

  14. Udformning af en forskningsprotokol

    DEFF Research Database (Denmark)

    Ridder, Hanne Mette Ochsner; Ottesen, Aase Marie

    2008-01-01

    Nogle demenssygdomme rammer især de forreste dele af hjernen, hvilket hos den enkelte person kan medføre svære psykiatriske symptomer. Der findes ingen specifik behandling af grundsygdommene for disse frontotemporaledemenstilstande, og symptomatisk medikamentel behandling af de psykiatriske sympt...

  15. Billeder af verdens svovl

    DEFF Research Database (Denmark)

    Samson, Kristine

    2014-01-01

    Film- og billedmediet har en særlig plads i skildringen af vores samfund og økonomi. Produktionen i de vestlige samfund består i dag primært af tegn, symboler, billeder og begær, mens de forgangne tiders maskinelle og, ikke mindst, manuelle bearbejdning af materialer – det vi stadigvæk umiddelbar...

  16. Ensretning af historieundervisningen

    DEFF Research Database (Denmark)

    Rønhede, Søren

    2008-01-01

    "Det er ikke kun i Putins Rusland, at statsmagten vil dirigere historieundervisningen." (Politiken havde fokuseret på "ensretning af historieundervisningen" i Rusland) "Kanonen fra 2006 er undfanget af Udvalget til Styrkelse af Historie i Folkeskolen. Dette udvalg havde regeringen nedsat; men...

  17. Forankring af skolemadsordninger

    DEFF Research Database (Denmark)

    Brinck, Nenna Maria; Kristensen, Niels Heine; Hansen, Mette Weinreich

    Denne rapport præsenterer resultaterne af de undersøgelser, der er gennemført i delprojekt 4 i EVIUS evalueringen. Fokus i dette delprojekt er forankringen af skolemadsordningerne. Af undersøgelsen fremgår det, at støtteordningen har virket bedst på skoler, hvor skolelederen har inddraget elever,...

  18. Digital formidling af kulturarv

    DEFF Research Database (Denmark)

    En af tidens store kulturelle dagsordner drejer sig om digital tilgængeliggørelse af kulturarv. Fortidens spor dukker op i nye former på nettet - næsten alle kulturinstitutioner arbejder med, og befolkningen har fået helt nye muligheder for at se med og deltage. Digital formidling af kulturarv...

  19. Petrologic and petrophysical evaluation of the Dallas Center Structure, Iowa, for compressed air energy storage in the Mount Simon Sandstone.

    Energy Technology Data Exchange (ETDEWEB)

    Heath, Jason E.; Bauer, Stephen J.; Broome, Scott Thomas; Dewers, Thomas A.; Rodriguez, Mark A

    2013-03-01

    The Iowa Stored Energy Plant Agency selected a geologic structure at Dallas Center, Iowa, for evaluation of subsurface compressed air energy storage. The site was rejected due to lower-than-expected and heterogeneous permeability of the target reservoir, lower-than-desired porosity, and small reservoir volume. In an initial feasibility study, permeability and porosity distributions of flow units for the nearby Redfield gas storage field were applied as analogue values for numerical modeling of the Dallas Center Structure. These reservoir data, coupled with an optimistic reservoir volume, produced favorable results. However, it was determined that the Dallas Center Structure cannot be simplified to four zones of high, uniform permeabilities. Updated modeling using field and core data for the site provided unfavorable results for air fill-up. This report presents Sandia National Laboratories petrologic and petrophysical analysis of the Dallas Center Structure that aids in understanding why the site was not suitable for gas storage.

  20. AFS Monitoring The CERN AFS Console

    CERN Document Server

    CERN. Geneva

    2008-01-01

    CERN's AFS installation serves between 1 and 2 billion accesses per day to its around 20'000 users. Keeping track of the system's overall status and trying to find problems before the users do is not a trivial task, esp. as the installation is growing in almost all aspects. This talk will present CERN's AFS Console, a Lemon- and web-based monitoring tool used by the AFS administrators at CERN to quickly identify problematic entities (servers, partitions, volumes etc.) and to assist them in solving the issues found.

  1. Prekarisering af arbejdsmarkedet

    OpenAIRE

    Sebelin, Randa; Søndergaard Krogh, Niels; Olesen Dørup, Marie; Nielsen, Emil; Westerbye, Nanna

    2005-01-01

    Rapporten redegør for konsekvenserne af fleksibiliseringen af arbejdslivet for den enkelte ansatte. Med et fokus på prekære/løse ansættelser gennemgås først sociologisk teori af bl.a. Ulrich Beck, Oskar Negt og Richard Sennett, som alle fremhæver de negative sider af en løs tilknytning til arbejdsmarkedet. Den danske arbejdsmarkedsmodel og flexicurity-modellen drages ind som baggrundsviden for en vigtig forståelse af den høje tillid til forhandlingsproces frem for lovgivning vi...

  2. Study and design of a hybrid wind-diesel-compressed air energy storage system for remote areas

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, H.; Dimitrova, M. [Wind Energy TechnoCentre, 51 Chemin de la mine, C.P. 1300, Murdochville, Quebec (Canada); Wind Energy Research Laboratory (WERL), Universite du Quebec a Rimouski, 300, allee des Ursulines, Quebec (Canada); Anti-icing Materials International Laboratory (AMIL), Universite du Quebec a Chicoutimi, 555, boulevard de l' Universite, Quebec (Canada); Younes, R. [Wind Energy Research Laboratory (WERL), Universite du Quebec a Rimouski, 300, allee des Ursulines, Quebec (Canada); 3M Laboratory - Faculty of Engineering, Lebanese University, Beirut (Lebanon); Ilinca, A. [Wind Energy Research Laboratory (WERL), Universite du Quebec a Rimouski, 300, allee des Ursulines, Quebec (Canada); Perron, J. [Anti-icing Materials International Laboratory (AMIL), Universite du Quebec a Chicoutimi, 555, boulevard de l' Universite, Quebec (Canada)

    2010-05-15

    Remote areas around the world predominantly rely on diesel-powered generators for their electricity supply, a relatively expensive and inefficient technology that is responsible for the emission of 1.2 million tons of greenhouse gas (GHG) annually, only in Canada. Wind-diesel hybrid systems (WDS) with various penetration rates have been experimented to reduce diesel consumption of the generators. After having experimented wind-diesel hybrid systems (WDS) that used various penetration rates, we turned our focus to that the re-engineering of existing diesel power plants can be achieved most efficiently, in terms of cost and diesel consumption, through the introduction of high penetration wind systems combined with compressed air energy storage (CAES). This article compares the available technical alternatives to supercharge the diesel that was used in this high penetration wind-diesel system with compressed air storage (WDCAS), in order to identify the one that optimizes its cost and performances. The technical characteristics and performances of the best candidate technology are subsequently assessed at different working regimes in order to evaluate the varying effects on the system. Finally, a specific WDCAS system with diesel engine downsizing is explored. This proposed design, that requires the repowering of existing facilities, leads to heightened diesel power output, increased engine lifetime and efficiency and to the reduction of fuel consumption and GHG emissions, in addition to savings on maintenance and replacement cost. (author)

  3. Preliminary feasibility evalution of compressed air storage power systems. Volume II. Appendices, period June 1975--December 1976

    Energy Technology Data Exchange (ETDEWEB)

    1976-12-01

    Interest in compressed air storage has been developing in Sweden, Finland, Denmark, England, and France, as well as the United States. One commercial unit is under construction in Huntorf, West Germany. Compressed air for peak power can be stored either in natural or man-made caverns. Only new excavations in hard rock down to depths of about 2500 feet are considered in this report. In 1974, conditions for underground storage were discussed in a Geological Survey of Potential Cavern Areas in New England, referred to as the CAINE report. In this survey of the northeast region, the rest of the corridor between Washington and Boston has been added. The rock formations in the entire area of about 45,000 square miles are evaluated. The physical properties of rocks and criteria for their evaluation in underground openings are discussed. Methods of rock excavation and the basis for selecting areas are considered. Information on bedrock units along the corridor is reviewed. A list of favorable rock formations is included.

  4. Application of wavelet filtering and Barker-coded pulse compression hybrid method to air-coupled ultrasonic testing

    Science.gov (United States)

    Zhou, Zhenggan; Ma, Baoquan; Jiang, Jingtao; Yu, Guang; Liu, Kui; Zhang, Dongmei; Liu, Weiping

    2014-10-01

    Air-coupled ultrasonic testing (ACUT) technique has been viewed as a viable solution in defect detection of advanced composites used in aerospace and aviation industries. However, the giant mismatch of acoustic impedance in air-solid interface makes the transmission efficiency of ultrasound low, and leads to poor signal-to-noise (SNR) ratio of received signal. The utilisation of signal-processing techniques in non-destructive testing is highly appreciated. This paper presents a wavelet filtering and phase-coded pulse compression hybrid method to improve the SNR and output power of received signal. The wavelet transform is utilised to filter insignificant components from noisy ultrasonic signal, and pulse compression process is used to improve the power of correlated signal based on cross-correction algorithm. For the purpose of reasonable parameter selection, different families of wavelets (Daubechies, Symlet and Coiflet) and decomposition level in discrete wavelet transform are analysed, different Barker codes (5-13 bits) are also analysed to acquire higher main-to-side lobe ratio. The performance of the hybrid method was verified in a honeycomb composite sample. Experimental results demonstrated that the proposed method is very efficient in improving the SNR and signal strength. The applicability of the proposed method seems to be a very promising tool to evaluate the integrity of high ultrasound attenuation composite materials using the ACUT.

  5. The new Center of Competence 'Compressed Air' at the Lucerne School of Engineering and Architecture; Aufbau des Druckluft-Kompetenzzentrums an der HTA Luzern. Phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Stadelmann, B.

    2006-07-01

    The Lucerne School of Engineering and Architecture was commissioned by the Swiss Federal Office of Energy in 2004 to establish (in a first phase) a Center of Competence 'Compressed Air'. The project aimed at assessing the potential improvements of compressed air systems in operation. The Center of Competence 'Compressed Air' was to be promoted through publications in professional journals and users alerted to the inefficiency of compressed air systems. Tests were performed on-site on six compressed air systems, focussing on the compressed air distribution lines. The analyses showed that while the compressed air generated in one small system did little more than cover the losses in its distribution system, leakages in the other systems were less serious. Nevertheless, all of the systems showed potential improvements, though pressure losses in all systems were acceptable. The project has raised the awareness of users of compressed air and contributed to the development of energy-efficient compressed air systems. The Swiss Federal Office of Energy's campaign 'Druckluft Schweiz' will continue with these efforts, further promoting efficient energy use. (author)

  6. Comparison between air boost inner compression process and nitrogen boost inner compression process%空气增压和氮气增压内压缩流程比较

    Institute of Scientific and Technical Information of China (English)

    张世田; 魏冰

    2011-01-01

    The process organization of the air boost inner compression air separation plant and nitrogen boost inner compression air separation plant is detailed, the allocation of main equipment and technical parameters are compared, and quantitative or qualitative%详细介绍空气增压内压缩流程和氮气增压内压缩流程空分设备的流程组织,通过主要设备配置和技术参数两方面的比较,得出了两种流程在产品提取率、增压机功率、设备投资和综合指标上定性或定量的比较结果。

  7. Hybrid Energy Storage System Based on Compressed Air and Super-Capacitors with Maximum Efficiency Point Tracking (MEPT)

    Science.gov (United States)

    Lemofouet, Sylvain; Rufer, Alfred

    This paper presents a hybrid energy storage system mainly based on Compressed Air, where the storage and withdrawal of energy are done within maximum efficiency conditions. As these maximum efficiency conditions impose the level of converted power, an intermittent time-modulated operation mode is applied to the thermodynamic converter to obtain a variable converted power. A smoothly variable output power is achieved with the help of a supercapacitive auxiliary storage device used as a filter. The paper describes the concept of the system, the power-electronic interfaces and especially the Maximum Efficiency Point Tracking (MEPT) algorithm and the strategy used to vary the output power. In addition, the paper introduces more efficient hybrid storage systems where the volumetric air machine is replaced by an oil-hydraulics and pneumatics converter, used under isothermal conditions. Practical results are also presented, recorded from a low-power air motor coupled to a small DC generator, as well as from a first prototype of the hydro-pneumatic system. Some economical considerations are also made, through a comparative cost evaluation of the presented hydro-pneumatic systems and a lead acid batteries system, in the context of a stand alone photovoltaic home application. This evaluation confirms the cost effectiveness of the presented hybrid storage systems.

  8. Performance study on three-stage power system of compressed air vehicle based on single-screw expander

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A new compressed-air engine system based on three-stage single screw expander was proposed to improve the performance of power system.Three different structure styles were presented,and the studies on the power performance and the distribution of expansion ratios between stages were carried out by programming and mathematical modeling of each style.Research results indicated that the best matches of expansion ratios with equal heat temperature for the air tank of pressure 30 MPa were seven-five-three for"first-stage heating"style,eight-five-three for"two-stage heating"style and five-five-four for"three-stage heating"style,respectively.Results also showed that heating up inlet air or increasing the expander efficiency might improve the power performance.The output power of the"two-stage heating"style is far higher than that of"first-stage heating"style and is a little lower than that of"three-stage heating"style.The new system showed good structure and power performances.

  9. Effect of air-entry angle on performance of a 2-stroke-cycle compression-ignition engine

    Science.gov (United States)

    Earle, Sherod L; Dutee, Francis J

    1937-01-01

    An investigation was made to determine the effect of variations in the horizontal and vertical air-entry angles on the performance characteristics of a single-cylinder 2-stroke-cycle compression-ignition test engine. Performance data were obtained over a wide range of engine speed, scavenging pressure, fuel quantity, and injection advance angle with the optimum guide vanes. Friction and blower-power curves are included for calculating the indicated and net performances. The optimum horizontal air-entry angle was found to be 60 degrees from the radial and the optimum vertical angle to be zero, under which conditions a maximum power output of 77 gross brake horsepower for a specific fuel consumption of 0.52 pound per brake horsepower-hour was obtained at 1,800 r.p.m. and 16-1/2 inches of Hg scavenging pressure. The corresponding specific output was 0.65 gross brake horsepower per cubic inch of piston displacement. Tests revealed that the optimum scavenging pressure increased linearly with engine speed. The brake mean effective pressure increased uniformly with air quantity per cycle for any given vane angle and was independent of engine speed and scavenging pressure.

  10. Compressed-air energy storage preliminary design and site-development program in an aquifer. Volume 2: Utility-system planning

    Science.gov (United States)

    1982-06-01

    The benefits derived from the integration of a compressed air energy storage facility with a hypothetical electrical network were analyzed. The analysis was based on three study scenarios each having a target generation mix of 65% base, 25% intermediate, and 10% peaking capacity. Scenarios of 100% coal, 50% coal and 50% nuclear, and 100% nuclear base load capacity additions were examined. Final results of the analyses indicate favorable economics when compressed air energy storage is installed as an alternative to combustion turbine peaking capacity on a system with a significant amount of oil-fired generation.

  11. Optimisation of compressed-air supply for control purposes at Valorec Services AG; Optimierung der Steuerluft - Versorgung bei der Valorec Services AG

    Energy Technology Data Exchange (ETDEWEB)

    Dott, R.; Afjei, T.

    2005-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of a project that looked at the possibilities of optimising the supply of compressed air provided around the clock by four compressor systems of varying ages in a facility in Basle, Switzerland. The initial situation is analysed and the potential for making savings is estimated. Various possibilities for improvement are considered including changing the topology of the compressed-air network, the replacement of certain compressors and a new control system. Appropriate measures are proposed and compared with new installations.

  12. ARCgame - gamification af undervisning

    DEFF Research Database (Denmark)

    Jensen, Camilla Gyldendahl

    2014-01-01

    Gamification er et begreb, der anvendes til at beskrive brugen af spilelementer i andre miljøer for at forbedre brugernes oplevelse. Følgende tekst har til formål at behandle emnet i forhold til af opnå en forståelse for de elementer der indvirker på en ”gamification af et undervisningsforløb”, her...

  13. Installation af opvaskemaskine

    DEFF Research Database (Denmark)

    Christiansen, J.; Skibstrup Eriksen, S.; Nielsen, F.

    Denne SBI-anvisning er et led i en serie om modernisering af installationerne i den ældre boligmasse. Den henvender sig til både beboere, husejere, VVS-installatører og andre interesserede. Anvisningen indeholder almene afsnit om valg og placering af opvaskemaskine, sagsforløb ved installation......, forhold til myndigheder, priser, finansieringsmuligheder m.m. Anvisningen indeholder endvidere tekniske afsnit om vandinstallation, afløb og elinstallation i forbindelse med installation af opvaskemaskine....

  14. Enhancement of the radar signal of air showers due to time compression

    CERN Document Server

    Stasielak, J; Engel, R; Neunteufel, P; Pekala, J; Šm\\'\\ida, R; Werner, F; Wilczyński, H

    2013-01-01

    We investigate the feasibility of detecting extensive air showers by the radar technique at viewing angles smaller than $\\sim 25^\\circ$ to the shower axis. Considering a bistatic radar setup and shower geometries in which the receiver points into the arriving shower, we simulate reflection of radio waves off the short-lived plasma produced by the high-energy shower particles in the air. Using the Thomson cross-section for scattering of radio waves and summing coherently contributions of the reflected radio wave over the volume of the plasma disk, we obtain the time evolution of the signal. We analyze the spectral power density of the radar echo and the received power. Based on the obtained results, we discuss possible modes of the radar detection of extensive air showers.

  15. Analytiske beregninger af induktionsvarme

    DEFF Research Database (Denmark)

    Henningsen, Poul

    Ved opvarmning af et emne ved hjælp af induktion, placeres emnet i en spole. Spolen påføres en vekselstrøm og der induceres en sekundær strøm langs emnets overflade. Dybden af det strømførende lag i emnet afhænger af den på spolens påtrykte strømfrekvens. Ved høje frekvenser løber strømmen i et t...

  16. Bestyrer af egen ro

    DEFF Research Database (Denmark)

    Søndergård, Birger; L. Friis, Klaus

    2000-01-01

    Evnen til at håndtere en indre uro synes at være blevet en væsentlig egenskab i forhold til udviklingen af vort samfund og de hastige brud i kontinuiteten af et liv, der leves. arbejdsforhold. stress. arbejdsmiljø. arbejdsliv......Evnen til at håndtere en indre uro synes at være blevet en væsentlig egenskab i forhold til udviklingen af vort samfund og de hastige brud i kontinuiteten af et liv, der leves. arbejdsforhold. stress. arbejdsmiljø. arbejdsliv...

  17. Ledelse af Organisationens Kreativitet

    DEFF Research Database (Denmark)

    Hedemann, Lars

    2008-01-01

    forskel, så er man som leder nødt til at arbejde mere målrettet med de medarbejdere som forventes at præstere et kreativt udbytte. Inspireret af analyseværktøjet "KEYS, Assessing the Work Environment for Creativity" udviklet af den amerikanske psykolog og ledelsesforsker ved Harvard University, Teresa...... Amabile, blev en undersøgelse derfor gennemført i udviklingsafdelingerne, Idéland og Idélab hos Bang og Olufsen, for at få et indblik i anvendeligheden af KEYS som inspirationskilde for succesfuld ledelse af organisationens kreativitet....

  18. Konstruktion af transducer

    DEFF Research Database (Denmark)

    Henriksen, Lars; Nielsen, Martin Pram

    Formålet med dette midtvejsprojekt er at udarbejde en transducer til måling af pressers stivhed. Dette er gjort på baggrund af en gennemgang af både presse- og stativ-typer samtidig med at udbøjningssituationen beskrives. Der introduceres en ide, der udgør grundkonceptet for opmålingsproceduren o...... færdige transducer – Load cellen. Strain gauge sørger for dataopsamlingen fra load cellen. Disse kalibreres således at transduceren er klar til de videre målinger der ligger i forlængelse af dette projekt....

  19. Compressed air energy storage: Preliminary design and site development program in an aquifer. Task 1: Establish facility design criteria and utility benefits

    Science.gov (United States)

    1980-10-01

    Compressed air energy storage (CAES) stores mechanical energy in the form of compressed air during off-peak hours, using power supplied by a large, high efficiency baseload power plant. At times of high electrical demand, the compressed air is drawn from storage and is heated in a combustor by the burning of fuel oil, after which the air is expanded in a turbine. Essentially all of the turbine output can be applied to the generation of electricity, unlike a conventional gas turbine which expends approximately two-thirds of the turbine shaft power in driving the air compressor. The separation of the compression and generation modes in the system results in increased net generation and greater premium fuel economy. Work performed in establishing facility design criteria for a CAES system with aquifer storage includes: determination of initial design bases; preliminary analysis of the CAES system; development of data for site-specific analysis of the CAES system; detailed analysis of the CAES system for three selected heat cycles; CAES power plant design; and an economic analysis of CAES.

  20. Compressed air energy storage: preliminary design and site development program in an aquifer. Final draft, Task 1: establish facility design criteria and utility benefits

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-10-01

    Compressed air energy storage (CAES) has been identified as one of the principal new energy storage technologies worthy of further research and development. The CAES system stores mechanical energy in the form of compressed air during off-peak hours, using power supplied by a large, high-efficiency baseload power plant. At times of high electrical demand, the compressed air is drawn from storage and is heated in a combustor by the burning of fuel oil, after which the air is expanded in a turbine. In this manner, essentially all of the turbine output can be applied to the generation of electricity, unlike a conventional gas turbine which expends approximately two-thirds of the turbine shaft power in driving the air compressor. The separation of the compression and generation modes in the CAES system results in increased net generation and greater premium fuel economy. The use of CAES systems to meet the utilities' high electrical demand requirements is particularly attractive in view of the reduced availability of premium fuels such as oil and natural gas. This volume documents the Task 1 work performed in establishing facility design criteria for a CAES system with aquifer storage. Information is included on: determination of initial design bases; preliminary analysis of the CAES system; development of data for site-specific analysis of the CAES system; detailed analysis of the CAES system for three selected heat cycles; CAES power plant design; and an economic analysis of CAES.

  1. [Management of penile trauma from compressed air gun in a child].

    Science.gov (United States)

    Girón-Vallejo, O; Zambudio, G; Ruiz-Pruneda, R; Hernindez, J P; Ruiz-Jiménez, J I

    2011-01-01

    We report on a 6-year old child with a penile injury resulting in the inclusion of a pellet in the cavernous body, by a fortuitous shot. Conservative approach with elective extraction of the bullet and cavernous body repair led to a satisfactory result, in better anatomic conditions. The patient did not have any perioperative complication. Accidents by air weapons are particularly important in children, because these weapons are erroneously considered as toys. Air gun injuries to head, neck and thorax have been often published, but these injuries are rare in the chidren genitourinary area.

  2. Homemade Firearm Suicide With Dumbbell Pipe Triggering by an Air-Compressed Gun: Case Report and Review of Literature.

    Science.gov (United States)

    Le Garff, Erwan; Delannoy, Yann; Mesli, Vadim; Berthezene, Jean Marie; Morbidelli, Philippe; Hédouin, Valéry

    2015-12-01

    Firearm suicides are frequent and well described in the forensic literature, particularly in Europe and the United States. However, the use of homemade and improvised firearms is less well described. The present case reports a suicide with an original improvised gun created using an air-compressed pellet gun and a dumbbell pipe. The aims of this study were to describe the scene, the external examination of the corpse, the body scan, and the autopsy; to understand the mechanism of death; and to compare the results with a review of the forensic literature to highlight the epidemiology of homemade firearm use, the tools used for homemade and improvised firearms in suicides versus homicides, and the manners in which homemade firearms are used (homicide or suicide, particularly in complex suicide cases).

  3. Storage of compressed air - Optimisation and measurement of an existing project example; Druckluftspeicherung: Optimierung / Ausmessung bestehendes Projektmuster

    Energy Technology Data Exchange (ETDEWEB)

    Brueckmann, P. [Brueckmann Elektronik, Davos Dorf (Switzerland); Cyphelly, I. [Cyphelly and Cie, Les Brenets (Switzerland)

    2007-06-15

    This short final report for the Swiss Federal Office of Energy (SFOE) deals with an additional project that augmented an earlier report on a compressed-air energy storage system. First tests are reported on that revealed that the chosen heat exchanger fulfils the thermal expectations with substantial reserves. Certain effects concerning the liquid piston system are described which showed that further development of the test infrastructure were required. This project was launched to further examine these problems. Difficulties with the liquids available which prohibited the intended exact series of measurements are commented on. The authors note that independent investigations by the Austrian company LINDE came to the same conclusions, thus confirming the function of the heat exchanger.

  4. Considerations on the effect of wind-tunnel walls on oscillating air forces for two-dimensional subsonic compressible flow

    Science.gov (United States)

    Runyan, Harry L; Watkins, Charles E

    1953-01-01

    This report treats the effect of wind-tunnel walls on the oscillating two-dimensional air forces in a compressible medium. The walls are simulated by the usual method of placing images at appropriate distances above and below the wing. An important result shown is that, for certain conditions of wing frequency, tunnel height, and Mach number, the tunnel and wing may form a resonant system so that the forces on the wing are greatly changed from the condition of no tunnel walls. It is pointed out that similar conditions exist for three-dimensional flow in circular and rectangular tunnels and apparently, within certain Mach number ranges, in tunnels of nonuniform cross section or even in open tunnels or jets.

  5. Characterizing Excavation Damaged Zone and Stability of Pressurized Lined Rock Caverns for Underground Compressed Air Energy Storage

    Science.gov (United States)

    Kim, Hyung-Mok; Rutqvist, Jonny; Jeong, Ju-Hwan; Choi, Byung-Hee; Ryu, Dong-Woo; Song, Won-Kyong

    2013-09-01

    In this paper, we investigate the influence of the excavation damaged zone (EDZ) on the geomechanical performance of compressed air energy storage (CAES) in lined rock caverns. We conducted a detailed characterization of the EDZ in rock caverns that have been excavated for a Korean pilot test program on CAES in (concrete) lined rock caverns at shallow depth. The EDZ was characterized by measurements of P- and S-wave velocities and permeability across the EDZ and into undisturbed host rock. Moreover, we constructed an in situ concrete lining model and conducted permeability measurements in boreholes penetrating the concrete, through the EDZ and into the undisturbed host rock. Using the site-specific conditions and the results of the EDZ characterization, we carried out a model simulation to investigate the influence of the EDZ on the CAES performance, in particular related to geomechanical responses and stability. We used a modeling approach including coupled thermodynamic multiphase flow and geomechanics, which was proven to be useful in previous generic CAES studies. Our modeling results showed that the potential for inducing tensile fractures and air leakage through the concrete lining could be substantially reduced if the EDZ around the cavern could be minimized. Moreover, the results showed that the most favorable design for reducing the potential for tensile failure in the lining would be a relatively compliant concrete lining with a tight inner seal, and a relatively stiff (uncompliant) host rock with a minimized EDZ. Because EDZ compliance depends on its compressibility (or modulus) and thickness, care should be taken during drill and blast operations to minimize the damage to the cavern walls.

  6. Air stacking and chest compression increase peak cough flow in patients with Duchenne muscular dystrophy

    OpenAIRE

    Magneide Fernandes Brito; Gustavo Antonio Moreira; Márcia Pradella-Hallinan; Sergio Tufik

    2009-01-01

    OBJETIVO: Avaliar a eficiência da tosse através do uso de duas manobras manuais de auxílio à tosse. MÉTODOS: Foram selecionados 28 pacientes portadores de distrofia muscular de Duchenne em uso de ventilação mecânica não-invasiva noturna e CVF < 60% do previsto. O pico de fluxo da tosse (PFT) foi medido, com o paciente sentado, em quatro momentos: com esforço expiratório máximo (EEM) de forma espontânea (basal), EEM associado à compressão torácica, EEM após empilhamento de ar com bolsa de vent...

  7. Midtvejsevaluering af EGA handlingsplanen

    DEFF Research Database (Denmark)

    Møller, Niels; Hasle, Peter; Christiansen, Jørgen Møller

    Center for Alternativ Samfundsanalyse (CASA) og Institut for Teknologi og Samfund ved Danmarks Tekniske Universitet har gennemført denne midtvejsevaluering af arbejdsmarkedets parters handlingsplan mod reduktion af ensidigt gentaget arbejde. Undersøgelsen viser, at der er sket en betydelig...

  8. Kvalitetsvurdering af sundhedsoplysende materiale

    DEFF Research Database (Denmark)

    Osler, Merete; Bech, Lars; Sybille, Bojlén;

    1990-01-01

    Lægeforeningens Hygiejnekomités arbejdsgruppe vedrørende sundhedsoplysning har udarbejdet en "huskeliste" til brug for en kvalitetsvurdering af skriftligt sundhedsoplysende materiale......Lægeforeningens Hygiejnekomités arbejdsgruppe vedrørende sundhedsoplysning har udarbejdet en "huskeliste" til brug for en kvalitetsvurdering af skriftligt sundhedsoplysende materiale...

  9. Coaching af dit studieliv

    DEFF Research Database (Denmark)

    Hansen, Rasmus Thorning

    2008-01-01

    En generel beskrivelse af de problemer specialestuderende sidder med og hvorledes coaching kan hjælpe med at (gen)skabe motivation og fokus......En generel beskrivelse af de problemer specialestuderende sidder med og hvorledes coaching kan hjælpe med at (gen)skabe motivation og fokus...

  10. Hvordan integration af it?

    DEFF Research Database (Denmark)

    Toft, Herdis

    2008-01-01

    Bourdieu-perspektiv og en analyse af data fra museums- og skoleprojektet Din egen historie på nettet vises det, hvordan børnene opbygger en legehabitus, det vil sige aktivt tilegner sig og anvender færdigheder i brug af æstetiske teknikker, som er formler, de kan improvisere frit over. Kendskab til formler...

  11. Kvalitetssikring af pressvejseprocessen

    DEFF Research Database (Denmark)

    Rasmussen, Mogens H.

    Det oprindelige formål med dette arbejde var udvikling af procesovervågning til pressvejsning ved en udvalgt hovedgeometri. Hovedgeometrien, ring/rør geometrien i materialekombinationerne stålring til tinbronzerør, blev valgt efter en forundersøgelse. På baggrund af et litteraturstudie samt indle...

  12. Administration af informationsmodeller

    DEFF Research Database (Denmark)

    Hundebøl, Jesper

    2013-01-01

    En informationsmodel er i denne sammenhæng en digital repræsentation af et givent byggeri. Både offentlige og private bygherrer anvender informationsmodeller, når der 'bygges digitalt'. I denne artikel undersøges det, hvilke konkrete udfordringer der følger af digitaliseringen, hvor gennemgribend...

  13. Evaluering af VIFT

    DEFF Research Database (Denmark)

    Pedersen, Michael Svendsen

    Denne rapport indeholder en ekstern evaluering af aktiviteter i VIFT, Videncenter for bedre undervisning af tosprogede elever, der er etableret som et samarbejde mellem Videncenter for tosprogethed & interkulturalitet (UC2) ved Professionshøjskolen København (UCC), tidligere CVU København & Nords...

  14. Raman af hvide pigmenter

    DEFF Research Database (Denmark)

    Reeler, Nini Elisabeth Abildgaard; Nielsen, Ole Faurskov; Sauer, Stephan P. A.;

    2013-01-01

    Et samspil mellem kunst og kemi. I et samarbejde mellem Statens Museum for Kunst og Kemisk Institut på KU er Ramanspek-troskopi brugt til at definere sammensætningen af blandinger af blyhvidt og calcit i maleriers hvide pigmenter....

  15. Kuratering af Samtidskunst

    DEFF Research Database (Denmark)

    Kuratering af Samtidskunst er den første bogudgivelse i Danmark, der fokuserer på kuratering som fag og praksis. Kuratering spiller en stadig større rolle i samtidskunsten. Bogen er en introduktion til skiftende forståelser af udstillings- og kuratorpraksisser og deres udfordringer, indkredset ge...

  16. Ud af guldrammerne

    DEFF Research Database (Denmark)

    Munch, Anders V.

    2006-01-01

    Diskussion af den internationale indflydelse på dansk symbolisme og skønvirke med udgangspunkt i Johan Rohdes rejsejournaler og Emil Hannovers anmeldelser af internationale udstillinger og udgivelser. Særligt fokus er Gesamtkunstwerk-tanken som baggrund for at koble kunst og kunsthåndværk....

  17. Behandlingseffekt af Digital Dermatitis

    DEFF Research Database (Denmark)

    Krogh, Kenneth; Thomsen, Peter

    2008-01-01

    af klovlidelser herunder især Digital Dermatitis. Klovregistreringerne viser, at der er stor dynamik og mange nyinfektioner af Digital Dermatitis svarende til problematikken ved mastitis. Behandlingseffekten ved Digital Dermatitis er høj (omkring 90 %) ved den udførte behandling. Behandlingen bestod...

  18. Anvendelse af genmodificerede planter

    DEFF Research Database (Denmark)

    Møller, F.

    I rapporten vurderes mulighederne for at gennemføre velfærdsøkonomiske analyser af anvendelsen af genmodificerede planter. Der gøres rede for kravene til konse-kvensbeskrivelsen og for mulighederne for at prissætte såvel de markedsrelaterede som de ikke-markedsrelaterede konsekvenser. Mulighederne...

  19. Dialektisk billede af Benjamin

    DEFF Research Database (Denmark)

    Bøggild, Jacob

    2004-01-01

    Anmeldelse af Lars Brückner: "Løse blade. Læseren, kritikeren og fortælleren Walter Benjamin"......Anmeldelse af Lars Brückner: "Løse blade. Læseren, kritikeren og fortælleren Walter Benjamin"...

  20. Indsattes organisering af selvforplejning

    DEFF Research Database (Denmark)

    Kjær Minke, Linda

    2012-01-01

    organiserer sig i madgrupper. Dette dels af økonomiske og praktiske hensyn, men madgrupperne fungerer også som mulighedsrum til fremvisning af forskellige former for kapital, positionering og magt. Madgrupperne har derfor både økonomiske og sociale formål og har betydning for indsattes strategier i...

  1. Implementering af evidensbaseret praksis

    DEFF Research Database (Denmark)

    Scheel, Linda Schumann; Tewes, Marianne; Petersen, Preben Ulrich

    2015-01-01

    Projektet omhandler implementering af den kliniske retningslinje om identifikation, forebyggelse og behandling af delirium – i denne sammenhæng relateret til hjertepatienter. Projektet foregår på to hospitaler i Hjertecentret på Rigshospitalet, et intensivt afsnit og et sengeafsnit, i tæt...

  2. Implementering af evidensbaseret praksis

    DEFF Research Database (Denmark)

    Scheel, Linda Schumann; Hansen, Ida Rode

    2014-01-01

    Projektet omhandler implementering af den kliniske retningslinje om identifikation, forebyggelse og behandling af delirium – i denne sammenhæng relateret til hjertepatienter. Projektet foregår på to hospitaler i Hjertecentret på Rigshospitalet, et intensivt afsnit og et sengeafsnit, i tæt...

  3. COP Prediction of an ejector refrigeration cycle combined with a vapour compression cycle for automotive air conditioning

    Directory of Open Access Journals (Sweden)

    Nat Suvarnakuta

    2014-03-01

    Full Text Available This paper presents the COP prediction of an ejector refrigeration cycle combined with a vapour compression cycle for automotive air conditioning. Using computational fluid dynamics (CFD technique, the performance of an ejector was analyzed in term of the entrainment ratio (Rm and critical back pressure (CBP. The results from this study were compared with a previous study of combined ejector refrigeration system for automotive air conditioning application [1] which the entrainment ratio (Rm were predicted from one-dimensional (1-D equation. The performance of an ejector (Rm and CBP from CFD and onedimensional method were analyzed and used as database for a mathematical modeling. In order to predict the COP of the combined system, a set of mathematical equations was developed using EES. The operating conditions are chosen accordingly as, intercooler temperature between 15 ๐ C and 25 ๐ C, condenser temperature equal to 35 ๐ C and evaporator temperature equal to 5 ๐ C. However, when generator temperatures are 80 ๐ C, 85 ๐ C and 90 ๐ C, the results showed average relative errors of the COP of an ejector refrigeration cycle (COPej, between CFD and 1-D are 44.64%, 50.47% and 59.68% respectively, and between CFD and 1-D NEW are 1.54%, 0.08% and 6.49% respectively.

  4. Technical and economic assessment of fluidized bed augmented compressed air energy-storage system. Volume II. Introduction and technology assessment

    Energy Technology Data Exchange (ETDEWEB)

    Giramonti, A.J.; Lessard, R.D.; Merrick, D.; Hobson, M.J.

    1981-09-01

    The results are described of a study subcontracted by PNL to the United Technologies Research Center on the engineering feasibility and economics of a CAES concept which uses a coal fired, fluidized bed combustor (FBC) to heat the air being returned from storage during the power production cycle. By burning coal instead of fuel oil, the CAES/FBC concept can completely eliminate the dependence of compressed air energy storage on petroleum fuels. The results of this assessment effort are presented in three volumes. Volume II presents a discussion of program background and an in-depth coverage of both fluid bed combustion and turbomachinery technology pertinent to their application in a CAES power plant system. The CAES/FBC concept appears technically feasible and economically competitive with conventional CAES. However, significant advancement is required in FBC technology before serious commercial commitment to CAES/FBC can be realized. At present, other elements of DOE, industrial groups, and other countries are performing the required R and D for advancement of FBC technology. The CAES/FBC will be reevaluated at a later date when FBC technology has matured and many of the concerns now plaguing FBC are resolved. (LCL)

  5. Compressed air storage concept BOP-B - Heat-exchanger and motor-generator; Machbarkeit des Druckluftspeicherkonzeptes BOP-B. Waermetauscher und Motgen

    Energy Technology Data Exchange (ETDEWEB)

    Brueckmann, P. [Brueckmann Elektronik, Davos Dorf (Switzerland); Cyphelly, I. [Cyphelly and Cie, Les Brenets (Switzerland); Lindegger, M. [Circle Motor AG, Guemligen (Switzerland)

    2006-11-15

    This illustrated final report for the Swiss Federal Office of Energy (SFOE) deals with project concerning a compressed-air energy storage system. The authors state that the BOP-B is a highly efficient compressor or air motor and can work efficiently if the compression or expansion of the air takes place in a mostly isothermal way. First tests made on the heat-exchanger unit are reported on and conclusions are drawn. A second part of the paper deals with the motor-generator unit (Motgen). The mechanical and electrical construction of the Motgen is described along with the results of tests performed on the unit. The results of measurements made are presented and discussed.

  6. CLEAN-AIR heat pump. Reduced energy consumption for ventilation in buildings by integrating air cleaning and heat pump. Final Report; CLEAN-AIR heat pump - Reduceret energiforbrug til ventilation af bygninger ved luftrensning integreret med luft varmepumpe. Slut rapport

    Energy Technology Data Exchange (ETDEWEB)

    Fang, L.; Olesen, Bjarne W.; Molinaro, G.; Simmonsen, P.; Skocajic, S. [Danmarks Tekniske Univ. Institut for Byggeri og Anlaeg, Lyngby (Denmark); Hummelshoej, R.M.; Carlassara, L. [COWI A/S, Lyngby, (Denmark); Groenbaek, H.; Hansen, Ole R. [Exhausto A/S, Langeskov (Denmark)

    2011-07-01

    This report summarizes task 1 of the Clean Air Heat Pump project - modelling and simulation on energy savings when using the clean air heat pump for ventilation, air cleaning and energy recovery. The total energy consumption of the proposed ventilation systems using clean air heat pump technology was calculated by a theoretical model and compared with the reference ventilation systems (conventional ventilation systems). The energy compared between the two systems includes energy used for heating, cooling and fan. The simulation and energy saving calculation was made for the application of the clean air heat pump in three typical climate conditions, i.e. mild-cold, mild-hot and hot and wet climates. Real climate data recorded from three cities in 2002 was used for the calculation. The three cities were Copenhagen (Denmark), Milan (Italy) and Colombo (Sir Lanka) which represent the above three typical climate zones. For the Danish climate (the mild cold climate), the calculations show that the ventilation system using clean air heat pump technology can save up to 42% of energy cost in winter compared to the conventional ventilation system. The energy saving in summer can be as high as 66% for the ventilation system with humidity control and 9% for the ventilation system without the requirement of humidity control. Since the Danish summer climate is very mild, over 80% of the yearly energy consumption for ventilation is used during winter season. It is, therefore, estimated that more than 35% annual energy saving for ventilation is expected in Denmark using the clean air heat pump ventilation technology. For the mild hot climate, e.g. the Italian climate, the calculations show that up to 63% of the energy saving can be achieved in summer season. For the winter mode, 17% reduction of the energy cost can be expected for the domestic use. For industrial use, the energy cost of the clean air heat pump may not be favourable due to the industrial price of gas in Italy is

  7. Smagen af svovl

    DEFF Research Database (Denmark)

    Madsen, P. V.; Sørensen, B. T.

    2007-01-01

    Et af Sydafrikas største industriområder ligger i landets tredje største by, Durban. Industriområdet kaldes for "South Durban Industrial Basin" (SDIB), hvor der er cirka 120.000 beboere. Boligerne ligger side om side med en bred variation af tung industri. Området er et sørgeligt eksempel på den ...... tidligere Apartheid styret byplanlægning, hvor regeringen i 1940'erne valgte at placere industri i et område hovedsageligt beboet af farvede og sorte mennesker....

  8. Termisk forgasning af biomasse

    DEFF Research Database (Denmark)

    Indlæggene i referatet er gengivet efter båndoptagelser. Der er dog foretaget nogle enklte omskrivninger af hensyn til læseligheden. Foredragsholdernes overheads er endvidere blevet lagt ind i referatet....

  9. Supervision af psykoterapi

    DEFF Research Database (Denmark)

    SUPERVISION AF PSYKOTERAPI indtager en central position i uddannelsen og udviklingen af psykoterapeuter. Trods flere lighedspunkter med psykoterapi, undervisning og konsultation er psykoterapisupervision et selvstændigt virksomhedsområde. Supervisor må foruden at være en trænet psykoterapeut kende...... supervisionens rammer og indplacering i forhold til organisation og samfund. En række kapitler drejer sig om supervisors opgaver, roller og kontrolfunktion, supervision set fra supervisandens perspektiv samt betragtninger over relationer og processer i supervision. Der drøftes fordele og ulemper ved de...... forskellige måder, hvorpå en sag kan fremlægges. Bogens første del afsluttes med refleksioner over de etiske aspekter ved psykoterapisupervision. Bogens anden del handler om de særlige forhold, der gør sig gældende ved supervision af en række specialiserede behandlingsformer eller af psykoterapi med bestemte...

  10. Test af Software

    DEFF Research Database (Denmark)

    Dette dokument udgør slutrapporten for netværkssamarbejdet ”Testnet”, som er udført i perioden 1.4.2006 til 31.12.2008. Netværket beskæftiger sig navnlig med emner inden for test af indlejret og teknisk software, men et antal eksempler på problemstillinger og løsninger forbundet med test af...... administrativ software indgår også. Rapporten er opdelt i følgende 3 dele: Overblik. Her giver vi et resumé af netværkets formål, aktiviteter og resultater. State of the art af software test ridses op. Vi omtaler, at CISS og netværket tager nye tiltag. Netværket. Formål, deltagere og behandlede emner på ti...... række danske software-, elektronik- og IT-virksomheder....

  11. Af Upraktiske Grunde

    DEFF Research Database (Denmark)

    Vaaben, Nana Katrine

    2001-01-01

    Artiklen baseres på studier af danske musikfans og handler om de objekter, de indsamler i forbindelse med at være fans. Der er to hovedargumenter, der løber gennem hele analysen. For det første at det indsamling af objekter handler om, er begær efter at kategorisere, ordne og systematisere, såled...

  12. Forebyggelse af kriminalitet

    DEFF Research Database (Denmark)

    Christiansen, U.; Jantzen, E.B.; Kirkegaard, O.

    Forebyggelse af kriminalitet i boligområder har længe stået på dagsordenen i alle vestlige samfund. Dansk Ingeniørforening og Ingeniørsammenslutningen har udviklet normer for kriminalpræventiv planlægning i boligområder siden midten af 1980'erne. To bebyggelser i Københavnsegnen er blevet planlag...

  13. Vitalisering af rettetheder

    DEFF Research Database (Denmark)

    Kristensen, René

    2012-01-01

    Kapitlet handler om at anvende det selvpsykologiske teorigrundlag i samspil med de systemisk konstruktionistiske ideer i arbejdet med at udvikle organisationer og samtidig kvalificere anvendelsen af PUMA -pædagogisk udredning i inklusionssammenhænge.......Kapitlet handler om at anvende det selvpsykologiske teorigrundlag i samspil med de systemisk konstruktionistiske ideer i arbejdet med at udvikle organisationer og samtidig kvalificere anvendelsen af PUMA -pædagogisk udredning i inklusionssammenhænge....

  14. Bearbejdning af Luhmanns organisationsteori

    DEFF Research Database (Denmark)

    Mortensen, Nils

    Som titlen siger, er det en gennemgang/præsertation af Luhmanns organisationsteori. Der er lagt særlig vægt på emnerne beslutning, ledelse opg forandring......Som titlen siger, er det en gennemgang/præsertation af Luhmanns organisationsteori. Der er lagt særlig vægt på emnerne beslutning, ledelse opg forandring...

  15. Assessment of air quality after the implementation of compressed natural gas (CNG) as fuel in public transport in Delhi, India.

    Science.gov (United States)

    Ravindra, Khaiwal; Wauters, Eric; Tyagi, Sushil K; Mor, Suman; Van Grieken, René

    2006-04-01

    Public transport in Delhi was amended by the Supreme Court of India to use Compressed Natural Gas (CNG) instead of diesel or petrol. After the implementation of CNG since April 2001, Delhi has the highest fraction of CNG-run public vehicles in the world and most of them were introduced within 20 months. In the present study, the concentrations of various criteria air pollutants (SPM, PM(10), CO, SO(2) and NO(x)) and organic pollutants such as benzene, toluene, xylene (BTX) and polycyclic aromatic hydrocarbons (PAHs) were assessed before and after the implementation of CNG. A decreasing trend was found for PAHs, SO(2) and CO concentrations, while the NO(x) level was increased in comparison to those before the implementation of CNG. Further, SPM, PM(10), and BTX concentrations showed no significant change after the implementation of CNG. However, the BTX concentration demonstrated a clear relation with the benzene content of gasoline. In addition to the impact of the introduction of CNG the daily variation in PAHs levels was also studied and the PAHs concentrations were observed to be relatively high between 10 pm to 6 am, which gives a proof of a relation with the limited day entry and movement of heavy vehicles in Delhi.

  16. Coaxially electrospun PVDF-Teflon AF and Teflon AF-PVDF core-sheath nanofiber mats with superhydrophobic properties.

    Science.gov (United States)

    Muthiah, Palanikkumaran; Hsu, Shu-Hau; Sigmund, Wolfgang

    2010-08-03

    This work reports the coaxial electrospinning of poly(vinylidene fluoride) (PVDF)-Teflon amorphous fluoropolymer (AF) and Teflon AF-PVDF core-sheath nanofiber mats yielding superhydrophobic properties. The coaxial electrospinning configuration allows for the electrospinning of Teflon AF, a nonelectrospinnable polymer, with the help of an electrospinnable PVDF polymer. PVDF-Teflon AF and Teflon AF-PVDF core-sheath fibers have been found to a have mean fiber diameter ranging from 400 nm to less than 100 nm. TEM micrographs exhibit a typical core-sheath fiber structure for these fibers, where the sheath fiber coats the core fiber almost thoroughly. Water contact angle measurements by sessile drop method on these core-sheath nanofiber mats exhibited superhydrophobic characteristics with contact angles close to or higher than 150 degrees. Surprisingly, PVDF-Teflon AF and Teflon AF-PVDF nanofiber mat surface properties were dominated by the fiber dimensions and less influenced by the type of sheath polymer. This suggests that highly fluorinated polymer Teflon AF does not advance the hydrophobicity beyond what surface physics and slightly fluorinated polymer PVDF can achieve. It is concluded that PVDF-Teflon AF and Teflon AF-PVDF core-sheath electrospun nanofiber mats may be used in lithium (Li)-air batteries.

  17. Implementation of a multi-lingual, Internet-supported benchmarking system for compressed-air installations; Umsetzung eines mehrsprachigen internetgestuetzten Benchmarking von Druckluftanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Radgen, P.

    2005-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) discusses how know-how can be improved and how optimisation activities can be stimulated in the area of compressed-air generation. The authors estimate that potential energy-savings of 20 to 40% are possible. The aim of the project - to introduce a benchmarking system already in use in Germany to the Swiss market - is discussed. This benchmarking is to help companies identify weak points in their compressed-air systems. An Internet-based information platform is introduced which was realised in 2004 and is being continually extended. The use of the benchmarking process is illustrated with a comprehensive flow-diagram and 'screen-shots' of the relevant Internet pages.

  18. 化纤生产压空系统节能措施%Energy Saving Measure of Compressed Air System of Fiber Mill

    Institute of Scientific and Technical Information of China (English)

    李留长; 戴玉萍

    2011-01-01

    介绍了在涤纶长丝生产过程中,采用节能改造措施,解决了由产品升级和产量增加所带来的压缩空气供气紧缺问题.通过压空供气管道改造,确保了生产系统供气稳定.介绍了对长丝生产主网络喷嘴进行不同孔径耗气量的测定,验证在压力范围、纺丝纤度、卷绕速度和喷嘴头数相同条件下,改造具有显著节气效果.同时介绍了压空系统采取减压增量节能技术,制定出相应下调压空系统离心机出口压力,可以在确保生产稳定的条件下,实现稳定生产和节约用电的显著效果.%The modification measure of energy saving was adopted to solve the shortage of compressed air supply caused by product upgrading and production increment in the polyester filament production. Through re-arrangement of compressed air supply piping, the air supply during the production was stable. The measurement was made on the consumption of interlacing nozzles with different diameters. It tested and verified that the result of the air saving was remarkable at the conditions of same pressure range, spinning titer, winding speed and nozzle head number. In the meanwhile, the paper presented the energy saving technology of pressure reduction and air supplying increment in compressed air system, outlet pressure of centrifugal compressor was cut down accordingly. Under this circumstance, the operation was smoothly and power saving was greatly.

  19. 压缩空气系统耗能与节能分析%Analyses of Energy Dissipation and Saving in Compressed Air System

    Institute of Scientific and Technical Information of China (English)

    何明勋; 陈国娟

    2012-01-01

    分析了压缩空气从压缩到输送过程的能量消耗损失,得出压缩过程损失约占总耗能的44%,卸载损失约占9%、降压使用损失约占3%,此外,泄露损失、无热再生干燥损失、管路输送损失以及环境温降损失都有不同程度的比例.针对以上各类损失,本文从设备选型、系统管路设计与安装以及优化运行3个方面提出了一系列节约能源、降低消耗的措施及改进方法,对提高能源利用效率、降低消耗有一定参考意义.%Energy lose of the compressed air system in compressing stage and transporting stage is analyzed,to definite and discriminate the whole process energy lose, air compressed energy lose, motor unloading energy lose and pressure degrading energy lose of the percentage are calculated with the CA series screw compressor as example,furthermore,the air transporting system energy lose caused by leakage, emission of regenerated dryer, pressure drop in piping line and temperature drop of the compressed air are also analyzed. To reduce the energy lose above, some measurements such as optimization equipment comfiguration, optimization piping design,system installation quality control and optimization operation perimeter are raised,these can be references for improving the energy utilization rate.

  20. Compressed Sensing-Based Multiuser Cooperative Networks

    Institute of Scientific and Technical Information of China (English)

    付晓梅; 崔阳然

    2016-01-01

    To avoid interference, compressed sensing is introduced into multiuser cooperative network. A coopera-tive compressed sensing and amplify-and-forward(CCS-AF)scheme is proposed, and it is proved that the channel capacity increases compared with the traditional cooperative scheme by considering the CCS-AF transmission ma-trix as the measurement matrix. Moreover, a new power allocation algorithm among the relays is proposed to im-prove the channel capacity. Numerical results validate the effectiveness of the proposed scheme.

  1. Anvendeligheden af GIS

    DEFF Research Database (Denmark)

    Winstrup, Mie; Levin, Gregor

    2011-01-01

    Fragmentering af naturen er en trussel mod biodiversiteten, og etablering af økologiske forbindelser/korridorer mellem naturområderne er én måde hvorved nedgangen i biodiversitet kan stoppes. Med Næstved Kommune som case-område har jeg undersøgt, hvordan analyser i GIS kan bruges til at udvælge...... omdannet til reelle korridorer, hvor bredden afhænger af arealdækket som forbindelserne krydser. I implementerings øjemed er det anvendeligt at vide om nogle forbindelser er særlig vigtige for at skabe mere sammenhængende natur. GIS er anvendeligt hertil, idet GIS kan bruges til at bestemme den enkelte...

  2. Realisering af Vision 2020

    DEFF Research Database (Denmark)

    Bertelsen, Niels Haldor; Hansen, Ernst Jan de Place

    Repræsentanter for byggesektoren har på 11 dialogmøder drøftet Erhvervs- og Byggestyrelsens "Vision 2020 - Byggeri med mening". Drøftelserne førte til formulering af en lang række initiativforslag til realisering af visionen. Den mest centrale udfordring bliver at reducere fejl og mangler i...... byggeriet. Branchen lægger også vægt på, at styringen af Vision 2020s reaisering sker i byggesektoren. Initiativforslagene er i rapporten samlet under 3 hovedområder. Det første hovedområde lægger vægt på bygningerne, brugerbehov og det globale samfund. Det andet omhandler processen og leverancesystemet...

  3. Ledelse af sociale institutioner

    DEFF Research Database (Denmark)

    Kofod, Kasper

    Ledelse af sociale institutioner giver et overblik over den enorme forandring, der er sket indenfor det sociale område i de sidste 25-30 år. Moderniseringen af den offentlige sektor har været gennemgribende, og udviklingen på det sociale område er gået mod større instirutioner og mod, at stadig...... flere beslutninger træffes lokalt. det betyder også,a t der kommeret øget fokus på ledelse af de enkelte sociale institutioner. Forandringer i omverdenedn som globalisering, individualisering, mangel på arbejdskraft og ændringer i omgangsformer påvirker også ledelsesvilkårene i de sociale institutioner...

  4. Reformen af erhvervsuddannelserne

    DEFF Research Database (Denmark)

    Jørgensen, Christian Helms

    2016-01-01

    Artiklen anlægger et politisk-historisk perspektiv på reformen af erhvervsuddannelserne (EUD) i 2014. Reformen markerede på nogle områder et markant brud med den hidtidige politik. Det gælder for ek-sempel indførelsen af adgangskrav og satsningen på talent og elite, som afløser de krav om social ...... ’blinde plet-ter’ og om den ureflekterede resultatstyring, som fortsætter med den aktuelle reform....

  5. Konstruktion af sandheden

    DEFF Research Database (Denmark)

    Nørreklit, Lennart

    2009-01-01

    Artiklen fremstiller sandhedsbegrebet som et læringsideal, som erstatter absolutisme og relativisme med læring. Indledningen bestemmer en problemorienteret ramme, som teorien indgår i: Mennesket er aktør, der danner virkelighed i form af relationer til sin omverden. Sandhedsbegrebet er forudsætni...... for en løbende sandhedsbestemmende læringsproces. Artiklen slutter med en diskussion af performative problemer, hvorigennem udsagn kan påvirke deres egen sandhedsværdi....

  6. Tension-Compression Fatigue of an Oxide/Oxide Ceramic Matrix Composite at Elevated Temperature in Air and Steam Environments

    Science.gov (United States)

    2015-03-26

    than several other advanced aerospace materials [15]. It is these qualities that make ceramics candidate materials for advanced aerospace ...TENSION-COMPRESSION FATIGUE OF AN OXIDE/OXIDE CERAMIC MATRIX COMPOSITE AT ELEVATED TEMPERATURE IN...is not subject to copyright protection in the United States. AFIT-ENY-MS-15-M-222 TENSION-COMPRESSION FATIGUE OF AN OXIDE/OXIDE CERAMIC MATRIX

  7. Opbygning af laboratoriefaciliteter til induktionsopvarmning

    DEFF Research Database (Denmark)

    Henningsen, Poul

    Denne rapport beskriver de faciliteter, der er opbygget til induktionsopvarmning i IPL’s svejselaboratorium. Beskrivelsen omfatter: • Indkøb og installation af frekvensgenerator • Fabrikation af spoler • Positionering og fastholdelse af emner og spole • Måling og registrering.......Denne rapport beskriver de faciliteter, der er opbygget til induktionsopvarmning i IPL’s svejselaboratorium. Beskrivelsen omfatter: • Indkøb og installation af frekvensgenerator • Fabrikation af spoler • Positionering og fastholdelse af emner og spole • Måling og registrering....

  8. Nibe Bredning, klapning af oprensningsmaterialer og vurdering af sedimentspredning

    DEFF Research Database (Denmark)

    Larsen, Torben; Bentzen, Thomas Ruby

    Formålet med undersøgelsen er at beregne spredningen af klapmateriale oprenset fra sejlrenden til Nibe samt Draget. Klappladsen for begge lokaliteter er umiddelbart nordvest for Klitgaard Hage. Beregningen er foretaget vha. af numerisk modellering af strømforhold samt sedimenttransport. Til formå...

  9. Inklusion af utilpassede unge

    DEFF Research Database (Denmark)

    2015-01-01

    Anholt-projektet repræsenterer en alternativ pædagogisk interventionsform for utilpassede og sårbare unge. Projektet, der i en årrække har været afprøvet af ungdomsskoler og ungdomsorganisationer i Danmark, Tyskland, Østrig, Spanien, Portugal og Italien, bygger på tanker om erfaringsbaseret, ufor...

  10. Benchmark af erhvervsuddannelserne

    DEFF Research Database (Denmark)

    Bogetoft, Peter; Wittrup, Jesper

    I dette arbejdspapir diskuterer vi, hvorledes de danske erhvervsskoler kan benchmarkes, og vi præsenterer resultaterne af en række beregningsmodeller. Det er begrebsmæssigt kompliceret at benchmarke erhvervsskolerne. Skolerne udbyder en lang række forskellige uddannelser. Det gør det vanskeligt...

  11. Benchmarking af kommunernes sagsbehandling

    DEFF Research Database (Denmark)

    Amilon, Anna

    Fra 2007 skal Ankestyrelsen gennemføre benchmarking af kommuernes sagsbehandlingskvalitet. Formålet med benchmarkingen er at udvikle praksisundersøgelsernes design med henblik på en bedre opfølgning og at forbedre kommunernes sagsbehandling. Dette arbejdspapir diskuterer metoder for benchmarking...

  12. Efterisolering af etageboliger

    DEFF Research Database (Denmark)

    Munch-Andersen, Jørgen

    Denne anvisning behandler efterisolering af etageboliger bygget i perioden 1850-1977. Der gøres rede for de grundlæggende principper for efterisolering og de bygningsfysiske krav til de enkelte bygningsdele. Anvisningen indeholder desuden vejledning i, hvordan efterisolering udføres i henholdsvis...

  13. Anmeldelse af: Gruppepsykologi

    DEFF Research Database (Denmark)

    Christensen, Bodil

    2009-01-01

    , kreativitet og nytænkning. Det er her, videnskabens virkelige fremskridt sker.” Sådan lyder et citat af Albert Einstein, som Lars Svedberg bruger for at sætte sin faglige fremstilling om gruppepsykologi i perspektiv. Gruppeorganisationen er nemlig ofte rum for/ eller kan være rum for denne synergieffekt, der...

  14. En skygge af modernitet

    DEFF Research Database (Denmark)

    2015-01-01

    Artiklen vil kort skitsere forskellige, samtidige konservative reaktioner på teknikken, hvis destruktive potentiale var blevet åbenbart i og med Første Verdenskrig, og derefter gennem en læsning af Drachmanns politiske og skønlitterære forfatterskab identificere nøgleelementer og begreber i Drach...

  15. Forplumring af historien

    DEFF Research Database (Denmark)

    Winther, Gorm

    2006-01-01

    Umiddelbart efer invasionen og samme år i 1956 fik Larsenfløjen udvirket en udtalelse fra DKPs forretningsudvalg, hvor det knæsattes at ethvert folk selvstændigt skulle kunne bestemme sin udviklingsvej, ligesom man fordømte påkaldelsen af hjælp fra broderpartierne udefra....

  16. Innovationen lider af teknologifetichisme

    DEFF Research Database (Denmark)

    Pedersen, Peder Holm

    2011-01-01

    Teknologisk innovation er udråbt som vejen til fremtiden for den danske velfærdsstat. Men vi risikerer at miste innovationens fulde potentiale, hvis vi tror, at innovation nødvendigvis skal lugte af teknologi. Nogle gange kan en sort affaldssæk også gøre det....

  17. Forankring af skolemadsordninger

    DEFF Research Database (Denmark)

    Brinck, Nenna Maria; Kristensen, Niels Heine; Hansen, Mette Weinreich

    I rapporten beskrives tre forældrebetalte skolemadsordninger, der blev etableret med støtte fra FødevareErhverv i 2008. Rapporten indeholder også resultater fra en spørgeskemaundersøgelse foretaget blandt elever og forældre i en 4. og 8. klasse på de tre caseskoler. Rapporten er en del af evaluer...

  18. Definition af et landdistrikt

    DEFF Research Database (Denmark)

    Søgaard, Villy

    2008-01-01

    Forskellige lande arbejder med meget forskellige definitioner af begrebet landdistrikt. Arbejdspapiret diskuterer først en række generelle krav til definitioner og anbefaler på den baggrund konkrete justeringer i forhold til den hidtidige danske praksis på området. Arbejdspapiret er blevet til i...

  19. Cycle-by-cycle Variations in a Direct Injection Hydrogen Enriched Compressed Natural Gas Engine Employing EGR at Relative Air-Fuel Ratios.

    Directory of Open Access Journals (Sweden)

    Olalekan Wasiu Saheed

    2014-07-01

    Full Text Available Since the pressure development in a combustion chamber is uniquely related to the combustion process, substantial variations in the combustion process on a cycle-by-cycle basis are occurring. To this end, an experimental study of cycle-by-cycle variation in a direct injection spark ignition engine fueled with natural gas-hydrogen blends combined with exhaust gas recirculation at relative air-fuel ratios was conducted. The impacts of relative air-fuel ratios (i.e. λ = 1.0, 1.2, 1.3 and 1.4 which represent stoichiometric, moderately lean, lean and very lean mixtures respectively, hydrogen fractions and EGR rates were studied. The results showed that increasing the relative air-fuel ratio increases the COVIMEP. The behavior is more pronounced at the larger relative air-fuel ratios. More so, for a specified EGR rate; increasing the hydrogen fractions decreases the maximum COVIMEP value just as increasing in EGR rates increases the maximum COVIMEP value. (i.e. When percentage EGR rates is increased from 0% to 17% and 20% respectively. The maximum COVIMEP value increases from 6.25% to 6.56% and 8.30% respectively. Since the introduction of hydrogen gas reduces the cycle-by-cycle combustion variation in engine cylinder; thus it can be concluded that addition of hydrogen into direct injection compressed natural gas engine employing EGR at various relative air-fuel ratios is a viable approach to obtain an improved combustion quality which correspond to lower coefficient of variation in imep, (COVIMEP in a direct injection compressed natural gas engine employing EGR at relative air-fuel ratios.

  20. Potential of a hybrid wind-diesel-compressed air system for a remote telecommunication station : part 2; Potentiel d'un Systeme hybride eolien-diesel-air comprime pour une station telecom isolee : partie 2

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, H.; Dimitrova, M. [Quebec Univ., Rimouski, PQ (Canada). Laboratoire LREE; Quebec Univ., Chicoutimi, PQ (Canada). Laboratoire LIMA; Chabour, H.; Ilinca, A. [Quebec Univ., Rimouski, PQ (Canada). Laboratoire LREE; Perron, J. [Quebec Univ., Chicoutimi, PQ (Canada). Laboratoire LIMA

    2009-07-01

    This paper reviewed the feasibility of using a hybrid wind-diesel-compressed air system to produce electricity at remote telecommunication stations. The hybrid system has been touted as a substitute for inefficient and costly diesel generators that contribute significant amounts of greenhouse gas to the atmosphere. In part 1 of this study, the authors compared different technical solutions for a high penetration wind-diesel system together with compressed air energy storage (CAES) and described the one that optimizes the performance and the cost of the overall system. Part 2 of the study examined the method of storing compressed air and the type of tank used. Results of numerical modeling of the system were then analyzed to determine the economic advantage of the hybrid system in terms of diesel fuel conservation and avoided greenhouse gases. It was concluded that the proposed design provides an increase in diesel power and efficiency, reduced fuel consumption and GHG emissions, in addition to economies on the maintenance and replacement cost of imported diesel. 3 tabs., 6 figs.

  1. Udlejers godkendelse af ny erhvervslejer

    DEFF Research Database (Denmark)

    Munk-Hansen, Carsten

    2009-01-01

    I artiklen er taget udgangspunkt i den »klassiske« afståelsessituation, hvor en lejer vil afhænde den i de lejede lokaler drevne virksomhed, og lejeren har afståelsesret til en af udlejer godkendt lejer, uden at kravene til den ny lejer er specificeret. På baggrund af Vestre Landsrets dom af 9/2 ...

  2. Monitering af korrosion i fjernvarmesystemer

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Nielsen, Lars Vendelbo; Thorarinsdottir, R.I.

    2004-01-01

    Kontrol af korrosion i fjernvarmesystemer foregår primært ved kontrol af vandkvaliteten. Generel korrosion af kulstofstål undgås således normalt ved at holde iltkoncentration og ledningsevne lav og pH høj. Lokaliseret korrosion forekommer dog i systemerne og disse korrosionsangreb detekteres i fo...

  3. Poser af papir og plast

    DEFF Research Database (Denmark)

    Thygesen, Jette

    2007-01-01

    Artiklen behandler de problemstillinger der er i forbindelse med fortolkning af det afgiftspligtige vareområde. I henhold til lov om afgift af visse emballager, poser, engangsservice, og pvc-folier, svares der afgift af poser, såfremt de frembyder bestemte karakteristika, herunder særligt om de er...

  4. Anmeldelse af Evolution, Literature and Film

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh

    2011-01-01

    Diskussion af basisproblemer i evolutionær fiktionsteori med udgangspunkt i en anmeldelse af Evolution, Literature and Film......Diskussion af basisproblemer i evolutionær fiktionsteori med udgangspunkt i en anmeldelse af Evolution, Literature and Film...

  5. Hætten af for Robin Hood

    DEFF Research Database (Denmark)

    Oxenbøll, Morten

    2010-01-01

    En historisk gennemgang af Robin Hood myten i anledning af den kommende Hood film med Russell Crowe i hovedrollen.......En historisk gennemgang af Robin Hood myten i anledning af den kommende Hood film med Russell Crowe i hovedrollen....

  6. En genlæsning af John Rawls i lyset af hans diskussion af forholdet til fremtidige generationer

    DEFF Research Database (Denmark)

    Lübcke, Poul

    2009-01-01

    På grundlag af en konsekventialistisk rekonstruktion af Rawls' politiske position gøres der rede for Rawls eksplicitte og implicitte vurdering af vores ansvar over for fremtidige generationer......På grundlag af en konsekventialistisk rekonstruktion af Rawls' politiske position gøres der rede for Rawls eksplicitte og implicitte vurdering af vores ansvar over for fremtidige generationer...

  7. Heat recovery from the compressed air of activation tanks at Herdorf sewage plant. Final report; Waermerueckgewinnung aus der Druckluft von Belebungsanlagen am Beispiel der Verbandsklaeranlage Herdorf. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Witte, H.; Strunkheide, J.; Eckhardt, R.

    2001-01-01

    Heat is removed from the compressed air of the activation tanks via a separate air cooler installed in the compressed-air line leading to the activation tank. The heat recovered will heat up the sludge in the digestion tank or will be fed into the heating system of the plant. The following goals are defined: Savings of heating oil; Saving of digestion gas as completely as possible; Power generation from the saved gas in a cogeneration unit; Power supply to the public grid. [German] Zielsetzung des Pilotprojektes ist die Nutzung der Druckluftwaerme von Belebungsanlagen als eine Moeglichkeit der Energieeinsparung auf Klaeranlagen. Die Nutzung der Verlustwaerme soll durch Abgriff der Waerme ueber einen separaten Luftkuehler erfolgen, der direkt in der Druckluftleitung zum Belebungsbecken installiert ist. Die auf diese Weise zurueckgewonnene Waerme soll zur Rohschlammaufheizung im Faulungsprozess dienen bzw. in das Betriebsheizungssystem eingespeist werden. Somit koennen folgende Ziele der Waermerueckgewinnungsanlage ins Auge gefasst werden: - Einsparung von Heizoel zu Heizzwecken in den Betriebsanlagen der Klaeranlage - Moeglichst komplette Einsparung von Faulgas im Heizkessel daraus folgend: - Mehrverstromung der im Heizkessel weniger verbrauchten Gasmengen im Blockheizkraftwerk (BHKW) mit dem Ergebnis: - Wirtschaftlicher Ertrag durch Einspeisung dieser Mehrmengen an Strom in das oeffentliche Versorgungsnetz. (orig.)

  8. Aflivning af heste

    DEFF Research Database (Denmark)

    Karlshøj, Merete; Fredsbo, Louise; Buhl, Rikke

    2007-01-01

    Det er efterhånden sjældent at heste dør af alderdøm. Ofte må ejer træffe den vanskelige beslutning om at lade hesten aflive. Da der tit er tale om en kær ven, er hesteejeren følelsesmæssigt påvirket. Det er derfor afgørende, at aflivningen foretages fagligt korrekt og professionelt.......Det er efterhånden sjældent at heste dør af alderdøm. Ofte må ejer træffe den vanskelige beslutning om at lade hesten aflive. Da der tit er tale om en kær ven, er hesteejeren følelsesmæssigt påvirket. Det er derfor afgørende, at aflivningen foretages fagligt korrekt og professionelt....

  9. Nedtrykt af negative nyheder

    DEFF Research Database (Denmark)

    Skovsgaard, Morten; Søberg, Pernille Frantz

    2016-01-01

    I adskillige år er det blevet debatteret, hvorvidt nyhedernes negative fokus har konsekvenser for borgerne, og om det i sid-ste ende får flere til at vende ryggen til nyhederne. Vores viden om effekterne af positive og negative nyheder er dog begrænset, og derfor undersøges det i denne artikel......, hvordan henholdsvis positive og negative tv-nyheder påvirker seernes humør, hukom-melse af information fra indslaget og lyst til at se yderligere tv-nyheder. Det gør vi i et survey-eksperiment (N=204), hvor tre grupper så enten et originalt indslag eller det samme indslag klippet med henholdsvis et...

  10. Opbygning af alliance

    DEFF Research Database (Denmark)

    Pedersen, Inge Nygaard

    2002-01-01

    Denne artikel er et forsøg på at bringe læseren med ind i atmosfæren, i oplevelsen og overvejelserne i forbindelse med opstart på et musikterapiforløb med en patient, som er meget svær at få kontakt med. Den er skrevet i et detaljerigt praksisnært sprog og har på én gang til for mål at starte på...... dokumentation af musikterapeutisk arbejde i børnepsykiatrien på musikterapiklinikken, APS og at formidle de mange facetter i et allianceopbyggende arbejde med en meget kontaktsvag patient. Artiklen beskriver prøveforløb og første del af et behandlingsforløb og er bygget op, således at praksisbeskrivelser fra...

  11. Relationel skabelse af ledelsesidentitet

    DEFF Research Database (Denmark)

    Hersted, Lone; Madsen, Charlotte Øland; Michelsen, Randi Riis

    2014-01-01

    forestillinger om, hvad det vil sige at være leder. Disse forestillinger er alle relationelt og kulturelt skabte og præger ofte ledere i deres daglige beslutningstagen og disponering i en sådan grad, at det får betydelige følgevirkninger for resten af organisationen og dens brugere/kunder og øvrige interessenter....

  12. Optisk kvantificering af gopler

    DEFF Research Database (Denmark)

    Christensen, Jens Tang

    efterfølgende med specielt udviklet software, med henblik på arts-, størrelses- og antalsfordeling. Indledende tests har vist, at mens Aurelia og Cyanea nemt registreres i lysgardinet, idet de lyser kraftigt op, er brydningsindekset for små individer af Mnemiopsis så tæt på vand, at der kræves stor kontrast på...

  13. Anvendelser af Pervasive Communication

    DEFF Research Database (Denmark)

    Brønsted, Jeppe

    I øjeblikket er den måde, vi kommunikerer på, ved at ændre sig drastisk. Fra at vi for få år siden var nødt til at nøjes med Internetkommunikation mellem stationære computere, forbindes en masse nye typer af enheder i dag på nye måder. Da vi nu ikke længere er bundet til en computer, der ikke kan...... flytte sig, bliver en masse nye ting mulige, fordi vi er forbundet med omverdenen i enhver kontekst. Da vi traditionelt ikke tænker i at være forbundet altid overalt er det ikke let at se, hvordan dette nye paradigme påvirker os i vores hverdag og hvordan vi kan udnytte det til nye forretnings- og...... forskningsmuligheder. For at gøre det hele lidt mere konkret, præsenteres i dette dokument en række eksempler på brug af Pervasive Communication. Udvalget af eksempler skal ikke ses som værende udtømmende, men snarere som håndplukkede eksempler der hver repræsenterer en genre. I dokumentet er både valgt...

  14. Innovation af innovation

    DEFF Research Database (Denmark)

    Harste, Gorm

    2009-01-01

    , at innovation af innovationen forsøges gennemført på en måde, hvor tiden kræves at forholde sig til sin egen tidslighed i form af fremtid, nutid, fortid og ikke mindst i form af samtidighed. I tiden skal vi iagttage, hvordan vi iagttager tiden. Vi dobbelt-koder tiden på samme måde, som forskning forsker i...... organisationssystemerne. De to typer systemer kan noget helt bestemt med fænomenet tid. De kan synkronisere. Analyseres organisationssystemer ser vi, imidlertid at innovation kræver ro. Stærkt innovative systemer er militærsystemet og kunstsystemet, der også inddrages, og hvor vi ser paradokset mellem innovation og...... involution. Tid er med et medium og ikke et lufttomt rum. Tid er end ikke en gasart, men udgør et solidt fluidum, som samfundet bader i og flyder i, konstant i bevægelse. Reformer forudsætter former, og innovation forudsætter involution. Kun sådan muliggøres evolution....

  15. Effects of intake air temperature on homogenous charge compression ignition combustion and emissions with gasoline and n-heptane

    Directory of Open Access Journals (Sweden)

    Zhang Jianyong

    2015-01-01

    Full Text Available In a port fuel injection engine, Optimized kinetic process (OKP technology is implemented to realize HCCI combustion with dual-fuel injection. The effects of intake air temperature on HCCI combustion and emissions are investigated. The results show that dual-fuel control prolongs HCCI combustion duration and improves combustion stability. Dual-fuel HCCI combustion needs lower intake air temperature than gasoline HCCI combustion, which reduces the requirements on heat management system. As intake air temperature decreases, air charge increases and maximum pressure rising rate decreases. When intake air temperature is about 55ºC, HCCI combustion becomes worse and misfire happens. In fixed dual fuel content condition, HC and CO emission decreases as intake air temperature increases. The combination of dual-fuel injection and intake air temperature control can expand operation range of HCCI combustion.

  16. Preparatory work for the start of the Swiss Compressed-Air Efficiency campaign and accompanying work on the setting-up of a compressed air competence centre; Vorarbeiten zum Start der Kampagne Druckluft effizient Schweiz und begleitende Arbeiten zum Aufbau eines Druckluftkompetenzzentrums

    Energy Technology Data Exchange (ETDEWEB)

    Radgen, P. [Fraunhofer-Institut fuer Systemtechnik und Innovationsforschung (ISI), Karlsruhe (Germany); Stadelmann, B. [Hochschule fuer Technik und Architektur (HTA) Luzern, Horw (Switzerland)

    2004-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) takes a look at how a campaign on compressed-air efficiency was prepared. Three work packages are described: The drawing-up of an implementation plan which defined the measures to be implemented by the campaign, incorporation of all relevant players in the preparation and acquisition of companies for the active realisation and co-financing of the activities, and a pilot project to optimise the compressed air supply in a chemical company. The institutions involved are introduced and the definition of the concept to be implemented is discussed. Measurement campaigns, benchmarking and publications to be made are discussed. The implementation of a pilot project at a chemicals company in Switzerland is described.

  17. High efficiency technical solutions for domestic tumble dryer design and modeling of a dryer - with mechanical very humic air compression; Evaluation des solutions techniques a haute efficacite energetique pour les seche-linges domestiques - conception et modelisation d'un seche-linge a re-compression mecanique d'air tres humide

    Energy Technology Data Exchange (ETDEWEB)

    Palandre, L.

    2005-12-15

    The aim of this work is to evaluate high efficiency solutions for domestic tumble dryers. A specific analysis focuses on the thermodynamic cycle with very humid air compression. The main components are designed. In a first time, two technologies of dryers are studied: evacuation dryer, and condensation dryer. Drying cycles are measured and analyzed. The energy consumption for the standard 5 kg cotton cycle is in the range of 3.3 kWh and 3.6 kWh. Two alternative solutions are proposed to reduce significantly the energy consumption: a heat pump dryer with R-134a, or an open cycle using steam or very humid air as refrigerant. In both cases, the energy consumption is cut by a factor 2. The measurement of convective heat transfer coefficients between linen and humid air has allowed to elaborate a correlation giving the Lewis function evolution with very high absolute humidity. Heat exchanges in the tumble have been characterized. A correlation giving the heat transfer coefficient in function of air mass flow rate, linen mass, and its relative humidity, is developed. An unsteady-state model is developed. It gives the drying cycle of the tumble dryer with mechanical very humid air compression. Simulations show that drying time could be reduced to 1 hour using this process compared to 2 hours with R-134a heat pump dryers. (author)

  18. AA-CAES. Opportunities and challenges of advanced adiabatic compressed-air energy storage technology as a balancing tool in interconnected grids

    Energy Technology Data Exchange (ETDEWEB)

    Marquardt, Roland; Moser, Peter [RWE Power AG, Essen (Germany). Forschung und Entwicklung, Neue Technologien; Hoffmann, Stephanie [GE Global Research Europe, Garching (Germany); Pazzi, Simone [GE Infrastructure, Oil and Gas, Firenze (Italy); Klafki, Michael [ESK GmbH (RWE Group), Freiberg (Germany); Zunft, Stefan [Deutsches Zentrum fuer Luft- und Raumfahrt (DLR), Stuttgart (Germany). Inst. fuer Technische Thermodynamik

    2008-07-01

    An expansion of CO{sub 2}-neutral energy supply is in the focus of European and national environmental policy and will be crucially supported by offshore wind power generation in future. Grid-compatible integration of these fluctuating electricity quantities will - in the medium term already - require substantial adjustments of the German grid and power plant system in order to cope with the upcoming new boundary conditions. The development of new technologies for large-scale electricity storage is a key element in future flexible European electricity transmission systems. Electricity storage in Adiabatic CAES power plants offers the prospect of making a substantial contribution to reach this goal. This concept allows efficient, local zero-emission electricity storage on the basis of compressed air in underground caverns. The compression and expansion of air in turbomachinery help to balance power generation peaks that are not demand-driven on the one hand and consumption-induced load peaks on the other. Before this concept can be implemented, however, several technical problems must be solved and technical development work done, especially in the field of turbomachinery and the required heat storage device. This paper outlines the technical possibilities and the need for development. Ongoing development activities are described and first interim results presented. (orig.)

  19. Korrosionshastigheder af rene zinkcoatings

    DEFF Research Database (Denmark)

    Bech-Nielsen, G.; Tang, Peter Torben; Ulrich, Dan

    1991-01-01

    Det har længe været den fremherskende opfattelse i galvanobranchen, at et zinkbad var et zinkbad og at der, tiltrods for de forskellige leverandørers gyldne løfter, ikke var den store forskel på de bade der kan købes på markedet idag. Det har ydermere været den almindelige opfattelse, at zinkbade......-bestandighed og udseende. Badenes alder har også vist sig at have endog meget stor betydning for kvaliteten af belægningerne....

  20. Kulturelle spejlinger af Profeten Muhammed

    DEFF Research Database (Denmark)

    Høgsbro Lading, Åse

    2008-01-01

    Artiklen er en analyse af to forløb i den såkaldte Muhammedkrise, der udspringer af Jyllandspostens offentliggørelse af karrikaturer af profeten Muhammed. Den første i 2006 ses som et  udspil, der først og frememst er styret  af markedsmæssige interesser, og hvor de globale reaktioner kom bag på ...... forsvar opleves  af avisen i splitting-kategorier: enten kan man sige alt, eller også har man ikke ytringsfrihed. Artiklen slutter med et ønske om, at mere komplekse syn på de globale relationer kan etableres...

  1. Anvendelse af MIP ved kildekarakterisering og vurdering af nedbrydning af chlorerede opløsningsmidler

    DEFF Research Database (Denmark)

    Broholm, Mette Martina; Janniche, Gry Sander; Damgaard, Ida;

    2014-01-01

    Membrane Interface Probing (MIP) er et 'direct push' screeningsværktøj, som kan anvendes ved karakterisering af forurenede grunde. Karakterisering af kildeområder med chlorerede opløsningsmidler (som DNAPL) udgør et vigtigt led i udviklingen af den konceptuelle forståelse, som er essentiel...... for risikovurdering og valg af afværgestrategi. Integreret karakterisering med en række metoder for direkte såvel som indirekte dokumentation af DNAPL i moræneler, herunder MIP, er beskrevet i Kerrn-Jespersen et al. (2013). Det samlede DNAPL-karakteriseringsprojekt er beskrevet i detaljer i Janniche et al. (2013). En...... vurdering af anvendte detektorer for MIP er foretaget af Olsson (2013). Ved karakterisering af forurening med bl.a. chlorerede opløsningsmidler er der behov for en vurdering af forureningssammensætning og nedbrydning. Tilsvarende vurdering er nødvendig, når udviklingen af stimuleret reduktiv dechlorering...

  2. En verden drevet af vindkraft

    DEFF Research Database (Denmark)

    Aukdal, Kenneth Martin

    2000-01-01

    For over 100 år siden opstillede Poul la Cour og et hold videnskabsmænd den første testvindmølle i Danmark. Det var den spæde start til en udvikling, der har gjort Danmark til verdens førende eksportør af vindkraftteknologi. Over 60% af den elektricitet,der produceres af vindmøller i verden i dag...

  3. Slaver af Væksten

    DEFF Research Database (Denmark)

    Nørgaard, Jørgen

    2004-01-01

    Artiklen rejser spørgsmålet om der, foruden den miljømæssige nødvendighed af at bremse væksten i Brutto National Produktet, også er direkte meneskelige fordele ved et sådant skridt. Dette aspekt er illustreret med de stigende negative følger af velstanden i USA og andre overflodslande, i form af ...

  4. Sammenligning af energiforbrug i supermarkeder

    DEFF Research Database (Denmark)

    Knudsen, Hans Jørgen Høgaard

    2005-01-01

    Formålet med det her omtalte projekt har været at sammenligne energiforbruget til køling i fire supermarkeder af sammenlignelig størrelse men med forskellig opbygning af køleanlægget. To af supermarkederne har nyudviklede kaskadeanlæg med CO2 i lavtemperaturkredsen og R404A i højtemperaturkredsen...

  5. Centralisering overfor decentralisering af varelagre

    DEFF Research Database (Denmark)

    Graungaard Pedersen, Søren; Zachariassen, Frederik

    2010-01-01

    store virksomheder. I Danmark går langt størstedelen af virksomheder under betegnelsen små og mellemstore virksomheder (SMV) og for en stor andel af disse, er udfordringen med effektiv styring af varelagre også relevant. Denne artikel beskæftiger sig med udfordringen mellem centralisering overfor...... decentralisering af varelagre i SMV. Det viser sig, at der er betydelige forskelle i, hvilke argumenter der er for og imod, når udfordringen ses fra et SMV-perspektiv....

  6. Coaching af sygedagpengemodtagere

    DEFF Research Database (Denmark)

    Coop Henriksen, Annemette

    SFI gennemførte i foråret 2008 til foråret 2009 en pilotundersøgelse om coaching. Undersøgelsen var designet som et lodtrækningsforsøg og omfattede 42 kvindelige sygedagpengemodtagere fra Rødovre Jobcenter, der var sygemeldt med psykiske lidelser i form af stress, depression eller udbrændthed eller...... med lidelser i bevægeapparatet. Undersøgelsen er bestilt og finansieret af Rødovre Jobcenter. I rapporten undersøges, om coaching kan bidrage til at bringe sygedagpengemodtagere i arbejde eller tættere på arbejdsmarkedet målt ved, om deltagerne får fx øget motivation, mere selvtillid, øget afklaring...... og færre symptomer på sygdom. Undersøgelsen viser, at gruppen, der har modtaget coaching, oplever en positiv udvikling i forhold til stress, depression og udbrændthed. Gruppen, der modtog coaching, har den tydeligste positive udvikling, men begge grupper har oplevet en helbredsmæssig fremgang i...

  7. Relevansen af Aristoteles' etik for konceptionen af eksistentiel terapi

    DEFF Research Database (Denmark)

    Dræby, Anders

    Siden sin undfangelse i begyndelsen af det 20. århundrede har den eksistentielle terapi repræsenteret et filosofisk funderet alternativ til de former for terapeutisk praksis, der er funderet i den funktionalistiske medicinske metafysik. Anvendelse af elementer fra Aristoteles' etik muliggør en...

  8. En systemteoretisk analyse af underviseres medlemskab af uddannelsessteder

    DEFF Research Database (Denmark)

    Kaspersen, Steffen Warming

    2014-01-01

    Afhandlingen undersøger ved hjælp af Niklas Luhmanns systemteori, hvordan undervisere på to uddannelsessteder der skal fusionere, er med til at bidrage til det nye uddannelsesstedets selvbeskrivelse. Der konkluderes, at undervisernes egen iagttagelse af uddannelsesstedet afgør hvilke faktorer der...

  9. Politisk brug af historien og legitimering af nutiden i Jugoslavien

    DEFF Research Database (Denmark)

    Humlebæk, Carsten

    2014-01-01

    Anmeldelse af: Tea Sindbæk: Usable History? Representations of Yugoslavia’s difϔicult past from 1945 to 2002, Aarhus University Press 2013.......Anmeldelse af: Tea Sindbæk: Usable History? Representations of Yugoslavia’s difϔicult past from 1945 to 2002, Aarhus University Press 2013....

  10. Simulering af dagslys i digitale modeller

    DEFF Research Database (Denmark)

    Villaume, René Domine; Ørstrup, Finn Rude

    2004-01-01

    Projektet undersøger via forskellige simuleringer af dagslys, kvaliteten af visualiseringer af komplekse lysforhold i digitale modeller i forbindelse med formidling af arkitektur via nettet. I en digital 3D model af Utzon Associates Paustians hus, simulers naturligt dagslysindfald med  forskellig...... Renderingsmetoder som: "shaded render" /  ”raytraceing” /  "Final Gather /  ”Global Illumination”...

  11. Compressed air energy storage power plants as an option for the grid integration of renewable energy sources. A comparison of the concepts; Druckluftspeicherkraftwerke als Option zur Netzintegration erneuerbarer Energiequellen. Ein Vergleich der Konzepte

    Energy Technology Data Exchange (ETDEWEB)

    Tuschy, Ilja [Fachhochschule Flensburg (Germany). Inst. fuer Energiesystemtechnik

    2008-07-01

    The integration of an increasing amount of power generation from renewable energy sources is a large challenge for the electricity supply. Apart from the compensation of varying production by supra-regional grids and apart from the further development of peak load power stations the energy storage is discussed as an option. Several power suppliers referred to compressed air energy storage plants as a possible solution. The authors of the contribution under consideration compare the different concepts for compressed air energy power stations systematically. A special emphasis is the thermodynamic evaluation of the different concepts. Also energy-technical aspects are addressed which decide on possibilities of application and perspectives of development for compressed air energy power stations.

  12. Anbefalinger til organisering af uddannelserne

    DEFF Research Database (Denmark)

    Andersen, Lars; Andersen, Lars Døvling; Hornemann, Birte C.;

    2009-01-01

    Notatet sammenfatter de diskussioner, som det af fakulteterne nedsatte udvalg vedrørende nye undervisnings- og eksamensformer har haft, og de anbefalinger til en omlægning af vores uddannelsessystem, som udvalget har valgt at give. Notatet er samtidig en begyndelse på en erfaringsudveksling om ny...

  13. Kvalifikation af den optiske aftastning

    DEFF Research Database (Denmark)

    Sobiecki, René

    Hvor koordinatmålemaskinen i årtier har indtaget en nøgleposition i en virksomhed til fremskaffelse af måledata, ser vi nu en udvikling i retning af mere og mere optisk måleudstyr. Profilprojektoren er vendt tilbage i en ny avanceret form. Fordele og ulemper ved mekanisk kontra optisk måling er v...

  14. Virkelighedsflugt og masser af sex

    DEFF Research Database (Denmark)

    Lorentzen, Rasmus Fink

    2011-01-01

    I artiklen laves en læsning af ungdomsromanen "6" (2010) af Ronni Andersen. Dernæst udfoldes en række litteraturpædagogiske forslag tilen undervisning i romanen i skolens ældste klasser. Arbejdsforslagene er baseret på en kompetencetilgang til danskfaget og rummer fire værksteder hvor eleverne sk...

  15. Midtvejsevaluering af Pulje til Landsbyfornyelse

    DEFF Research Database (Denmark)

    Jensen, Jesper Ole; Blach, Vigdis E. Magnusdatter

    og bidrage til en helhedsorienteret og fremadrettet indsats i en række kommuner i de danske yderområder. Midtvejsevalueringen belyser effekten af puljen og kommunernes erfaringer med administrationen af puljen. Evalueringen er gennemført som en internet-baseret spørgeskemaundersøgelse (survey) blandt...

  16. Evaluering af den fleksible barselsorlov

    DEFF Research Database (Denmark)

    Marianne Olsen, Bente

    forældreorloven. Undersøgelsen viser også, at der er en række områder, hvor kommunerne mener, at orlovsreglerne udgør en administrativ byrde. Det bliver ekstra tungt, fordi det IT-system, der understøtter administrationen af barselsreglerne, ikke fungerer optimalt. Omring to tredjedel af de adspurgte...

  17. Evalueringen af den fleksible barselorlov

    DEFF Research Database (Denmark)

    Marianne Olsen, Bente

    forældreorloven. Undersøgelsen viser også, at der er en række områder, hvor kommunerne mener, at orlovsreglerne udgør en administrativ byrde. Det bliver ekstra tungt, fordi det IT-system, der understøtter administrationen af barselsreglerne, ikke fungerer optimalt. Omring to tredjedel af de adspurgte...

  18. Techno-economic assessment of the need for bulk energy storage in low-carbon electricity systems with a focus on compressed air storage (CAES)

    Science.gov (United States)

    Safaei Mohamadabadi, Hossein

    Increasing electrification of the economy while decarbonizing the electricity supply is among the most effective strategies for cutting greenhouse gas (GHG) emissions in order to abate climate change. This thesis offers insights into the role of bulk energy storage (BES) systems to cut GHG emissions from the electricity sector. Wind and solar energies can supply large volumes of low-carbon electricity. Nevertheless, large penetration of these resources poses serious reliability concerns to the grid, mainly because of their intermittency. This thesis evaluates the performance of BES systems - especially compressed air energy storage (CAES) technology - for integration of wind energy from engineering and economic aspects. Analytical thermodynamic analysis of Distributed CAES (D-CAES) and Adiabatic CAES (A-CAES) suggest high roundtrip storage efficiencies ( 80% and 70%) compared to conventional CAES ( 50%). Using hydrogen to fuel CAES plants - instead of natural gas - yields a low overall efficiency ( 35%), despite its negligible GHG emissions. The techno-economic study of D-CAES shows that exporting compression heat to low-temperature loads (e.g. space heating) can enhance both the economic and emissions performance of compressed air storage plants. A case study for Alberta, Canada reveals that the abatement cost of replacing a conventional CAES with D-CAES plant practicing electricity arbitrage can be negative (-$40 per tCO2e, when the heat load is 50 km away from the air storage site). A green-field simulation finds that reducing the capital cost of BES - even drastically below current levels - does not substantially impact the cost of low-carbon electricity. At a 70% reduction in the GHG emissions intensity of the grid, gas turbines remain three times more cost-efficient in managing the wind variability compared to BES (in the best case and with a 15-minute resolution). Wind and solar thus, do not need to wait for availability of cheap BES systems to cost

  19. Potential of a hybrid wind-diesel-compressed air system for a remote telecommunication station : part 1; Potentiel d'un systeme hybride eolien-diesel-air comprime pour une station telecom isolee : partie 1

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, H.; Dimitrova, M. [Quebec Univ., Rimouski, PQ (Canada). Laboratoire LREE; Quebec Univ., Chicoutimi, PQ (Canada). Laboratoire LIMA; Chabour, H.; Ilinca, A. [Quebec Univ., Rimouski, PQ (Canada). Laboratoire LREE; Perron, J. [Quebec Univ., Chicoutimi, PQ (Canada). Laboratoire LIMA

    2009-07-01

    This paper reviewed the main characteristics of various electricity storage techniques and their potential for both long and short-term applications. In particular, it discussed the feasibility of using a hybrid wind-diesel-compressed air system to produce electricity at remote telecommunication stations. The hybrid system has been touted as a substitute for inefficient and costly diesel generators that contribute significant amounts of greenhouse gas to the atmosphere. Some low and high penetration wind-diesel hybrid systems have been studied in order to reduce the diesel consumption. This paper demonstrated that the use of a high penetration wind-diesel system together with compressed air energy storage (CAES) is a viable alternative to improve the overall percentage of renewable energy and reduce the cost of electricity in remote areas where a good wind resource is available. In part 1 of this study, the authors compared different technical solutions for the CAES system and described the one that optimizes the performance and the cost of the overall system. 3 figs.

  20. Udvikling af CO2 neutralt byrumsarmatur

    DEFF Research Database (Denmark)

    Poulsen, Peter Behrensdorff; Dam-Hansen, Carsten; Corell, Dennis Dan

    Denne rapport indeholder en beskrivelse af arbejdet udført i og resultaterne af forsknings- og udviklingsprojektet ” Udvikling af CO2 neutralt byrumsarmatur” og udgør slutrapportering for dette projekt.......Denne rapport indeholder en beskrivelse af arbejdet udført i og resultaterne af forsknings- og udviklingsprojektet ” Udvikling af CO2 neutralt byrumsarmatur” og udgør slutrapportering for dette projekt....

  1. Anmeldelse af World Drug Report 2005

    DEFF Research Database (Denmark)

    Møller, Kim

    2005-01-01

    Internationale udfordringer i spændingsfeltet mellem organiseret kriminalitet og narkotika. Værdien af det illegale narkotikamarked. Skabelsen af et Illicit Drug Index. Ny organisationsstruktur bag udgivelsen af denne WDR. Udgivelsesdato: December......Internationale udfordringer i spændingsfeltet mellem organiseret kriminalitet og narkotika. Værdien af det illegale narkotikamarked. Skabelsen af et Illicit Drug Index. Ny organisationsstruktur bag udgivelsen af denne WDR. Udgivelsesdato: December...

  2. Compression/expansion rheology of oil/water interfaces with adsorbed proteins. Comparison with the air/water surface

    NARCIS (Netherlands)

    Benjamins, J.; Lyklema, J.; Lucassen-Reynders, E.H.

    2006-01-01

    Dynamic interfacial tensions and surface dilational moduli were measured for four proteins at three fluid interfaces, as a function of time and concentration. The proteins-ß-casein, ß-lactoglobulin, bovine serum albumin, and ovalbumin - were adsorbed from aqueous solution against air, n-tetradecane,

  3. Digitalisering af det eksisterende byggeri

    DEFF Research Database (Denmark)

    Sørensen, Nils Lykke; Øien, Turid Borgestrand

    2010-01-01

    Digitalisering af det eksisterende byggeri er en vanskelig og uendelig opgave. Det giver kun mening at digitalisere eksisterende byggeri, når man har et konkret behov, og da kun at indhente og lagre de informationer, som man strategisk eller konkret har behov for. Erhvervs og Byggestyrelsen har...... iværksat en analyse af strategier for digitalisering af det eksisterende byggeri. I forbindelse hermed vil denne rapport undersøge problemerne og potentialerne ved at digitalisere den eksisterende bygningsmasse, både hvad angår hvilke dele heraf der er relevant at digitalisere, til hvilket niveau, samt de...

  4. Modellering af elforbrug til netanalyse

    DEFF Research Database (Denmark)

    Østergaard, Jacob

    I denne rapport undersøges mulighederne for at etablere en model for elforbruget, der kan anvendes ved analyser af det østdanske transmissionsnet. Rapporten henvender sig til ingeniører og beslutningstagere, der ønsker viden om betydningen af en nøjagtig elforbrugsmodel og om mulighederne for i p...... simuleringsresultater med mindre usikkerhed, og der opnås en integration mellem eksisterende systemer, idet data fra en række systemer bl.a. Panda, elforbrugsprognoser, elforbrugspaneler og stationsprognoser kan udnyttes til etableringen af en model....

  5. Cost benefit analysis and energy savings of using compression and absorption chillers for air conditioners in hot and humid climates

    Science.gov (United States)

    Shekarchian, M.; Moghavvemi, M.; Motasemi, F.; Mahlia, T. M. I.

    2012-06-01

    The electricity consumption growth has increased steadily in the recent decade which is a great concern for the environment. Increasing the number of high-rise air-conditioned buildings and the rapid use of electrical appliances in residential and commercial sectors are two important factors for high electricity consumption. This paper investigates the annual energy required for cooling per unit area and the total energy cost per unit area for each type of air conditioning systems in hot and humid climates. The effects of changing the coefficient of performance (COP) of absorption chillers on cost saving was also investigated in this study. The results showed that using absorption chillers for cooling will increase the amount of energy consumption per unit area; however the energy cost per unit area will decrease. In addition this research indicates that for each 0.1 increment in COP of absorption chillers, there is about 500 USD/m2 saved cost.

  6. Fluctuations of the Solitary Bubble at the Separation from the Air Cavity, Compressed by the Magnetic Field in Magnetic Liquid

    Directory of Open Access Journals (Sweden)

    M.L. Boev

    2013-12-01

    Full Text Available In the article, on the basis of the concept of "display" of geometry of a free surface of the "low-magnetic" environment by the topography of isolines of the module of intensity of a magnetic field, it is studied a form of a free surface of magnetic fluid in a static condition at the initial stage of rapprochement of a ring magnet with a surface of a column of magnetic fluid in a tube and at a stage of pressing of a cavity to a bottom. It is shown that the separation of bubbles from an air cavity occurs in close proximity to the plane of symmetry of a ring magnet on its axis. It is described the method and experimental installation for studying the possibility of electromagnetic indication of sizes of the air bubbles, being in magnetic fluid. It is discussed the results of experimental research on process of a separation of solitary air bubble from a cavity, contained in magnetic fluid and squeezed by ponderomotive forces of a magnetic field which are of interest for creation of essentially new technique of the dosed supply of small amount of gas in the reactor.

  7. Compressed air energy storage: preliminary design and site development program in an aquifer. Final draft, Task 2: Volume 2 of 3. Characterize and explore potential sites and prepare research and development plan

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-12-01

    The characteristics of sites in Indiana and Illinois which are being investigated as potential sites for compressed air energy storage power plants are documented. These characteristics include geological considerations, economic factors, and environmental considerations. Extensive data are presented for 14 specific sites and a relative rating on the desirability of each site is derived. (LCL)

  8. En beskrivelse af tidligere stofmisbrugere

    DEFF Research Database (Denmark)

    Hecksher, Dorte

    2004-01-01

    Artiklen fokuserer på en del af et sample fra en større opfølgningsundersøgelse af døgnbehandlingsindsatsen overfor stofmisbrugere i Danmark. Formålet med artiklen er at beskrive den stoffri gruppe forud for indskrivning i døgnbehandling og i de første to år efter udskrivning fra døgnbehandling. ...

  9. Udredning af xerostomi og hyposalivation

    DEFF Research Database (Denmark)

    Pedersen, Anne Marie Lynge; Dynesen, Anja Weirsøe; Jensen, Siri Beier

    2011-01-01

    Mundtørhed kræver grundig undersøgelse Xerostomi er ofte associeret til betydelig nedsat spytsekretion, men kan forekomme, uden at der objektivt kan påvises nedsat spytsekretion. Udredning af patienter, som klager over mundtørhed, bør således altid inkludere en omhyggelig anamnese, en detaljeret ...... adækvate behandlingsstrategier for den patient, som lider af xerostomi og nedsat spytsekretion....

  10. Implementering af MultifunC

    DEFF Research Database (Denmark)

    Henze-Pedersen, Sofie; Kohl, Katrine Syppli; Oldrup, Helene

    (MultifunC), som allerede havde vist lovende resultater i Norge og Sverige. I 2011 og 2012 åbnede to danske MultifunC-institutioner derfor i henholdsvis København og Aarhus. Denne rapport undersøger, hvordan implementeringen af MultifunC-programmet er forløbet i Danmark. Undersøgelsen viser, at ingen af de...... to danske institutioner lykkedes med at implementere MultifunC tilfredsstillende i løbet af implementeringsperioden. Det har fx været vanskeligt at implementere det tætte tværfaglige samarbejde mellem medarbejdere med forskellige fagprofessionelle baggrunde, som behandlingsprogrammet indebærer. Det har...... desuden været særdeles vanskeligt for de danske MultifunC-institutioner at få etableret det eksterne samarbejde med de sociale myndigheder i kommunerne, politiet, skoler og praktiksteder samt fritidstilbud i nærområdet, som også er en væsentlig del af behandlingsprogrammet. Undersøgelsen af finansieret af...

  11. På sporet af de gyldne opskrifter?

    DEFF Research Database (Denmark)

    Poulfelt, Flemming

    2015-01-01

    Børsen Ledelse. Markedet for kogebøger er stort. For der produceres hvert år et hav nye af slagsen. Nogle udgives af kendte kokke, nogle af særlige eksperter inden for kost og motion, og andre af personer, der har en ægte interesse inden for gastronomi og mad. På ledelsesområdet findes en...

  12. Demokratiseringen af den politiske diskurs i Polen

    DEFF Research Database (Denmark)

    Arnfast, Juni Søderberg

    1999-01-01

    Gennem en analyse af brugen af personlige pronominer i politiske tekster fra udvalgte, polske medier diskuteres forandringerne i den polske, politiske diskurs gennem 1980'erne. Det påvises at det kommunistiske styres anvendelse af pronominet 'vi' skifter konnotationer i retning af en mindre ideol...

  13. Kants Kritik af dømmekraften

    DEFF Research Database (Denmark)

    Introduktion til Kants Kritik af dømmekraften bestående af otte artikler, der følger værkets egen tematiske opbygning......Introduktion til Kants Kritik af dømmekraften bestående af otte artikler, der følger værkets egen tematiske opbygning...

  14. Dimensionering af rørisolering

    DEFF Research Database (Denmark)

    Olufsen, P.

    Meddelelsen gennemgår metoderne til dimensionering af termisk isolering af tekniske installationer i bygninger med hovedvægten på isolering af rør og beholdere i varme- og brugsvandsanlæg. Grundlaget for opstilling af mindstekrav til rørisolering diskuteres og der sammenlignes med tilsvarende...

  15. Overvejelser vedr. effektvurdering af det Digitale Sygehus

    DEFF Research Database (Denmark)

    Andersen, Povl Erik Rostgård; Wit, Camilla Kølsen de

    2001-01-01

    Nærværende skrift indeholder en beskrivelse af de overvejelser og planer, der er lavet på projektet 'Effektvurdering af Det Digitale Sygehus' medio dec. 2001.......Nærværende skrift indeholder en beskrivelse af de overvejelser og planer, der er lavet på projektet 'Effektvurdering af Det Digitale Sygehus' medio dec. 2001....

  16. Ultraspectral sounder data compression review

    Institute of Scientific and Technical Information of China (English)

    Bormin HUANG; Hunglung HUANG

    2008-01-01

    Ultraspectral sounders provide an enormous amount of measurements to advance our knowledge of weather and climate applications. The use of robust data compression techniques will be beneficial for ultraspectral data transfer and archiving. This paper reviews the progress in lossless compression of ultra-spectral sounder data. Various transform-based, pre-diction-based, and clustering-based compression methods are covered. Also studied is a preprocessing scheme for data reordering to improve compression gains. All the coding experiments are performed on the ultraspectral compression benchmark dataset col-lected from the NASA Atmospheric Infrared Sounder (AIRS) observations.

  17. Experimental Study of Ambient Air Temperature Effects on The Performance of a General Vapor-Compression Refrigeration Cycle

    Directory of Open Access Journals (Sweden)

    Ayad T. Mustafa

    2013-05-01

    Full Text Available         In this work an experimental study for the vapor – compression refrigeration cycle has been performed under temperature range of  9.7-32°C. The effect of      varying temperature on heat exchangers pressures, cooling capacity, net power consumption, and coefficient of performance COP are studied .                                   The results indicated that condenser pressure, evaporator pressure, and power consumption increased with the increase of temperature. The data also indicated that cooling capacity increased as temperature increased until 15.6°C then after it decreased with further temperature increase. Also COP follow the same tread of cooling capacity.                                                                                                              

  18. Betydningen af pesticider for forekomsten af vilde bier

    DEFF Research Database (Denmark)

    Bruus, Marianne; Dupont, Yoko Luise; Grant, Ruth;

    Både i Danmark og andre steder er der observeret en nedgang i de insekter, der bestøver landmandens afgrøder og de vilde planter. Tilbagegangen falder sammen med, at landbrugsdriften er blevet mere intensiv, og anvendelsen af pesticider er øget. Vi ved imidlertid ikke, hvilken rolle pesticiderne...... vigtige for bestøvningen af fx kløver og mange vilde planter. Da humlebier og andre vilde bier har en anden adfærd og placerer deres reder andre steder end honningbierne, er det ikke givet, at de er beskyttet mod pesticideksponering, selv om honningbierne er. I pilotprojektet ”Betydningen af pesticider...... for forekomsten af vilde bier og honningbier” har Aarhus Universitet på to landbrugsbedrifter gennemført en indledende undersøgelse af, om humlebier udsættes for pesticider i danske landbrugsområder. Humlebistader blev sat ud i to værkstedsområder (ved Fensten og Rodstenseje syd for Odder), hvor driftsformen...

  19. Effekter ved udlicitering af offentlige opgaver

    DEFF Research Database (Denmark)

    Petersen, Ole Helby; Hjelmar, Ulf; Vrangbæk, Karsten;

    2014-01-01

    Denne rapport præsenterer resultaterne af en systematisk forskningsoversigt over studier af effekter af udlicitering publiceret i perioden 2011-2014. Forskningsoversigten opdaterer en AKF-rapport fra 2011, som gennemgik publicerede undersøgelser af effekter ved udlicitering i perioden 2000-2011 (......-2014. Indsamlingen og vurderingen af studier er afsluttet d. 27. oktober 2014, hvilket betyder, at studier udgivet efter denne dato ikke indgår i forskningsoversigten....

  20. Domesticeringen af Ford i Danmark

    DEFF Research Database (Denmark)

    Wagner, Michael

    Det amerikanske automobilfirma Ford Motor Company med hovedkvarter i Detroit begyndte at drive forretning i Danmark omkring 1906. De første aktiviteter blev konsolideret samme år ved udnævnelsen af motorforhandleren F. Bülow & Co. til salgsagent i Danmark og importør af Ford automobiler til det...... skandinaviske marked. Dermed havde Ford tidligt fået et stærkt fodfæste i Nordeuropa, som udviklingen i salget af Ford autobiler de næste årtier til fulde skulle demonstrere. Ford Motor Company er i dag den fjerde største bilproducent på verdensmarkedet, men går man tilbage til 1920'rne var selskabet førende...... med en markedsandel på mere end 50%. En position som Ford måtte afgive til General Motors i løbet af årtiet. I Danmark var mere end hvert andet indregistreret automobil i 1930 antageligt af mærket Ford, og helt frem til verdenskrigens udbrud var Ford Motor Company et brand, som spillede en meget...

  1. "Compressed" Compressed Sensing

    CERN Document Server

    Reeves, Galen

    2010-01-01

    The field of compressed sensing has shown that a sparse but otherwise arbitrary vector can be recovered exactly from a small number of randomly constructed linear projections (or samples). The question addressed in this paper is whether an even smaller number of samples is sufficient when there exists prior knowledge about the distribution of the unknown vector, or when only partial recovery is needed. An information-theoretic lower bound with connections to free probability theory and an upper bound corresponding to a computationally simple thresholding estimator are derived. It is shown that in certain cases (e.g. discrete valued vectors or large distortions) the number of samples can be decreased. Interestingly though, it is also shown that in many cases no reduction is possible.

  2. Brug af alternativ isolering i forbindelse med renovering af ældre etageejendomme

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place

    2003-01-01

    Resume af rapport om praktiske erfaringer med brug af alternative isoleringsmaterialer i en renoveringsopgave, udarbejdet af Byfornyelse København m.fl. under Energistyrelsens udviklingsprogram "Miljø- og arbejdsmiljøvenlig isolering"...

  3. Control of oil-wetting on technical textiles by means of photo-chemical surface modification and its relevance to the performance of compressed air filters

    Energy Technology Data Exchange (ETDEWEB)

    Bahners, Thomas, E-mail: bahners@dtnw.de [Deutsches Textilforschungszentrum Nord-West gGmbH (DTNW), Adlerstr. 1, 47798 Krefeld (Germany); Mölter-Siemens, Wolfgang; Haep, Stefan [Institut für Energie- und Umwelttechnik e.V. (IUTA), Bliersheimer Str. 60, 47229 Duisburg (Germany); Gutmann, Jochen S. [Deutsches Textilforschungszentrum Nord-West gGmbH (DTNW), Adlerstr. 1, 47798 Krefeld (Germany); Universität Duisburg-Essen, Physikalische Chemie and CENIDE, Universitätsstr. 2, 45141 Essen (Germany)

    2014-09-15

    Highlights: • The oil repellence of textile fabrics was increased following the Wenzel concept. • Fiber surfaces were micro-roughened by means of pulsed UV laser irradiation. • Subsequent UV-induced grafting yielded pronounced oil repellence. • The grafting process conserved the delicate topography of the fiber surfaces. • The modified fabrics showed favorable drainage behavior in oil droplet separation. - Abstract: A two-step process comprising a surface roughening step by excimer laser irradiation and a post-treatment by photo-grafting to decrease the surface free energy was employed to increase the oil repellence of technical fabrics made of poly(ethylene terephthalate) (PET). The modification was designed to improve the performance of multi-layer filters for compressed air filtration, in which the fabrics served to remove, i.e. drain, oil separated from the air stream. In detail, the fibers surfaces were roughened by applying several laser pulses at a wavelength of 248 nm and subsequently photo-grafted with 1H,1H,2H,2H-perfluoro-decyl acrylate (PPFDA). The oil wetting behavior was increased by the treatments from full wetting on the as-received fabrics to highly repellent with oil contact angles of (131 ± 7)°. On surfaces in the latter state, oil droplets did not spread or penetrate even after one day. The grafting of PPFDA alone without any surface roughening yielded an oil contact angle of (97 ± 11)°. However, the droplet completely penetrated the fabric over a period of one day. The drainage performance was characterized by recording the pressure drop over a two-layer model filter as a function of time. The results proved the potential of the treatment, which reduced the flow resistance after 1-h operation by approximately 25%.

  4. Study and design of a hybrid wind-diesel-compressed air system for providing electricity to a remote telecommunication station; Etudes et conception d'un systeme hybride eolien-diesel-air comprime pour l'electrification d'une station de telecommunications isolee

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, H.; Dimitrova, M. [TechnoCentre eolien Gaspesie-les Iles, Gaspe, PQ (Canada); Ilinca, A. [Quebec Univ., Rimouski, PQ (Canada); Perron, J. [Quebec Univ., Chicoutimi, PQ (Canada)

    2010-07-01

    This poster reported on a study that examined the feasibility of using a hybrid wind-diesel-compressed air system to produce electricity at remote telecommunication stations. Low and high penetration wind-diesel hybrid systems were studied in order to reduce the diesel consumption. The use of a high penetration wind-diesel system together with compressed air energy storage (CAES) was shown to be a viable alternative to improve the overall percentage of renewable energy and reduce the cost of electricity in remote areas where a good wind resource is available. Different technical solutions for the CAES system were compared. refs., figs.

  5. Reduktionen af satsen for selskabsskat gør en ændring af creditreglerne aktuel

    DEFF Research Database (Denmark)

    Rønfeldt, Thomas; Werlauff, Erik

    2013-01-01

    Artiklen analyserer sammenhængen mellem satsen for selskabsskatten og maksimeringen af creditlempelsen ved aktivitet i udlandet. Der argumenteres for, at en nedsættelse af selskabsskatten aktualoiserer behovet for en gfennemgribende reform af reglerne om maksimeret credit.......Artiklen analyserer sammenhængen mellem satsen for selskabsskatten og maksimeringen af creditlempelsen ved aktivitet i udlandet. Der argumenteres for, at en nedsættelse af selskabsskatten aktualoiserer behovet for en gfennemgribende reform af reglerne om maksimeret credit....

  6. Preliminary design study of underground pumped hydro and compressed-air energy storage in hard rock. Volume 4: System planning studies

    Science.gov (United States)

    1981-04-01

    Preliminary design and planning studies of water compensated compressed air energy storage (CAES) and underground pumped hydroelectric (UPH) power plants are presented. The costs of the CAES and UPH plant designs, and the results of economic evaluations performed for the PEPCO system are presented. The PEPCO system planning analysis was performed in parallel stages with plant design development. Analyses performed early in the project indicated a requirement for 1000 MW/10,000 MWH of energy storage on a daily operating schedule, with economic installation in two segments of 500 MW in 1990 and 1997. The analysis was updated eighteen months later near the end of the project to reflect the impact of new growth projections and revised plant costs. The revised results indicated economic installations for either UPH or CAES of approximately 675 MW/6750 MWH on a daily cycle, installed in blocks of approximately 225 MW in 1990, 1993 and 1995. Significant savings in revenue requirements and oil fuel over the combustion turbine alternative were identified for both CAES and UPH.

  7. Coal-fuelled systems for peaking power with 100% CO2 capture through integration of solid oxide fuel cells with compressed air energy storage

    Science.gov (United States)

    Nease, Jake; Adams, Thomas A.

    2014-04-01

    In this study, a coal-fuelled integrated solid oxide fuel cell (SOFC) and compressed air energy storage (CAES) system in a load-following power production scenario is discussed. Sixteen SOFC-based plants with optional carbon capture and sequestration (CCS) and syngas shifting steps are simulated and compared to a state-of-the-art supercritical pulverised coal (SCPC) plant. Simulations are performed using a combination of MATLAB and Aspen Plus v7.3. It was found that adding CAES to a SOFC-based plant can provide load-following capabilities with relatively small effects on efficiencies (1-2% HHV depending on the system configuration) and levelized costs of electricity (∼0.35 ¢ kW-1 h-1). The load-following capabilities, as measured by least-squares metrics, show that this system may utilize coal and achieve excellent load-tracking that is not adversely affected by the inclusion of CCS. Adding CCS to the SOFC/CAES system reduces measurable direct CO2 emission to zero. A seasonal partial plant shutdown schedule is found to reduce fuel consumption by 9.5% while allowing for cleaning and maintenance windows for the SOFC stacks without significantly affecting the performance of the system (∼1% HHV reduction in efficiency). The SOFC-based systems with CCS are found to become economically attractive relative to SCPC above carbon taxes of 22 ton-1.

  8. Lessons from Iowa : development of a 270 megawatt compressed air energy storage project in midwest Independent System Operator : a study for the DOE Energy Storage Systems Program.

    Energy Technology Data Exchange (ETDEWEB)

    Holst, Kent (Iowa Stored Energy Plant Agency, Traer, IA); Huff, Georgianne; Schulte, Robert H. (Schulte Associates LLC, Northfield, MN); Critelli, Nicholas (Critelli Law Office PC, Des Moines, IA)

    2012-01-01

    The Iowa Stored Energy Park was an innovative, 270 Megawatt, $400 million compressed air energy storage (CAES) project proposed for in-service near Des Moines, Iowa, in 2015. After eight years in development the project was terminated because of site geological limitations. However, much was learned in the development process regarding what it takes to do a utility-scale, bulk energy storage facility and coordinate it with regional renewable wind energy resources in an Independent System Operator (ISO) marketplace. Lessons include the costs and long-term economics of a CAES facility compared to conventional natural gas-fired generation alternatives; market, legislative, and contract issues related to enabling energy storage in an ISO market; the importance of due diligence in project management; and community relations and marketing for siting of large energy projects. Although many of the lessons relate to CAES applications in particular, most of the lessons learned are independent of site location or geology, or even the particular energy storage technology involved.

  9. Implementering af drift i byggeri

    DEFF Research Database (Denmark)

    Damgaard, Torben; Erichsen, Pia Bruun

    På trods af, at der løbende er udgivet materiale der argumenterer for at tænke drift ind i byggeprocesser, er der problemer med, at det faktisk sker. Undersøgelser viser, at forskellige barrierer kan være årsag til problemerne. Disse barrierer kan opstilles inden for følgende kategorier: Projekt...... med i byggeriet. Som følge af dette skal der løbende skabes nye relationer mellem parterne, og der skal arbejdes sammen på nye måder. De forskellige barrierer syntes at være mest fremtrædende ved offentlige byggerier, men også private innovative byggerier er præget af barriererne. Der er flere...

  10. Styring af international transfer pricing

    DEFF Research Database (Denmark)

    Reuther, Peter; Rossing, Christian Plesner

    2011-01-01

    Nærværende artikel introducerer international transfer pricing, dels som et skatteretligt fænomen og dels som et værktøj til planlægning og økonomisk styring af koncernforbundne selskaber i en multinational virksomhed (MNV). Med udgangspunkt i en case-analyse af MNV’en gives der et konkret eksempel...... international transfer pricing i betragtning, når økonomiske styringssystemer i en MNV skal anvendes til planlægning og opfølgning....

  11. På sporet af den tabte sans

    DEFF Research Database (Denmark)

    Nielsen, Thomas Rosendal

    2014-01-01

    Analyse af en workshop om interaktive strategier i børneteater for børn. Workshoppen fandt sted på Dramatikkens hus i Oslo og blev ledet af Sara Topsøe-Jensen, kunstneriske leder af teatret Carte Blanche.......Analyse af en workshop om interaktive strategier i børneteater for børn. Workshoppen fandt sted på Dramatikkens hus i Oslo og blev ledet af Sara Topsøe-Jensen, kunstneriske leder af teatret Carte Blanche....

  12. Fiktionen, der var ude af sig selv

    DEFF Research Database (Denmark)

    Hansen, Kim Toft

    2007-01-01

    På baggrund af en analyse af Lars Frosts roman Smukke biler efter krigen (2004) reflekterer jeg over fiktionen som på én gang selvberoende og selvnedbrydende størrelse, og der henvises til Adornos æstetik som en mulig teoretisk ramme for begribelsen af dette tilsyneladende paradoks.......På baggrund af en analyse af Lars Frosts roman Smukke biler efter krigen (2004) reflekterer jeg over fiktionen som på én gang selvberoende og selvnedbrydende størrelse, og der henvises til Adornos æstetik som en mulig teoretisk ramme for begribelsen af dette tilsyneladende paradoks....

  13. Af materialitet er du kommet

    DEFF Research Database (Denmark)

    Skiveren, Tobias; Gregersen, Martin

    2015-01-01

    På baggrund af bogen "Den materielle drejning. En (ny) optik i og på aktuel dansk litteratur", der udkommer i 2016, skitserer artiklen, hvordan en filosofisk-teoretisk nyorientering under overskriften "den materielle drejning" i øjeblikket udkrystalliserer sig på en henholdsvis økokritisk, posthu......, posthuman og kropsmaterialistisk strømning i dansk samtidslitteratur....

  14. Udvikling af ledelse via ledelseskoncepter

    DEFF Research Database (Denmark)

    Frimann, Søren; Thomassen, Anja Overgaard; Keller, Hanne Dauer

    I denne artikel beskæftiger vi os med, hvordan ledelse kan udvikles i spændingsfeltet mellem udefrakommende krav om mere fælles fodslag i ledelsen og den enkelte leders behov for at tilpasse sin ledelsesstil til den aktuelle kontekst. Konkret ser vi nærmere på, hvordan der blandt en gruppe af led...

  15. Virksomhedernes opfattelse af arbejdsmarkedets "restgrupper"

    DEFF Research Database (Denmark)

    Larsen, Christian Albrekt

    2010-01-01

    Artiklen beskriver, hvorledes danske arbejdsgivere opfatter ældre ledige, ledige indvandrere og ledige med lang forudgående ledighed. Det teoretiske udgangspunkt er, at arbejdsmarkedets fundamentale informationsproblemer fører til brug af statistisk diskrimination og frygt for «lemons». Analyserne...

  16. Signalement af en tabers temperament

    DEFF Research Database (Denmark)

    Holm, Claus

    2009-01-01

    En moderne taber tager ting for tungt, benytter sig ikke nok af glemslens nådegave og har vanskeligt ved at finde en lykkelig fortælling om fortiden. Derfor siger vi i dag: Tag en slapper, tag en pille og tag nogle samtaler....

  17. Forskningsoversigt - Effekterne af Cooperative Learning

    DEFF Research Database (Denmark)

    Larsen, Lea Lund

    Kan Cooperative Learning - en undervisningsform hvor lærerens tid ved tavlen mindskes og hvor de lærende samarbejder om stoffet - maksimere de lærendes indlæring og medvirke til en forbedring af deres interpersonelle og kommunikative kompetencer, samt øge deres motivation for læring? Den megen...

  18. Patentering af det humane genom

    DEFF Research Database (Denmark)

    Sommer, Tine

    2004-01-01

    Direktiv 98/44/EF om retlig beskyttelse af bioteknologiske opfindelser blev gennemført i dansk ret med ikrafttrædelse den 30. juli 2000. Direktivet indeholder i artikel 5 en central bestemmelse som giver adgang til patent på humane gener. I artikel 5, stk. 3, er indføjet et skærpet krav til...

  19. Bliver seksualitetsforskningen lykkelig af moralismeanklager?

    DEFF Research Database (Denmark)

    Frederiksen, Maja Bissenbakker

    2010-01-01

    Anmeldelse: ‘Piger bliver ikke lykkelige af analsex’ er underholdende og sine steder forstemmende læsning om de problematiske måder, hvorpå offentlige debatter de seneste år har gjort seksualitet til genstand for en overvældende bekymring og deraf følgende krav om regulering og kontrol"...

  20. Domesticeringen af Ford i Danmark

    DEFF Research Database (Denmark)

    Wagner, Michael

    2011-01-01

    Det amerikanske automobilfirma Ford Motor Company (1903) med hovedkvarter i Detroit begyndte at drive forretning i Danmark omkring 1906. Dermed havde Ford tidligt fået et stærkt fodfæste i Nordeuropa, som udviklingen i salget af Ford automobiler de næste årtier til fulde skulle demonstrere...

  1. Reformering af vejforvaltning i Afrika

    DEFF Research Database (Denmark)

    Kristiansen, Jørgen

    2004-01-01

    I 1980´erne skete der et hurtigt forfald af vejnettet i mange lande i Afrika syd for Sahara. Både Verdensbanken, EU og de bilaterale donorer blev klar over, at nye institutionelle løsninger var nødvendige, hvis udviklingen skulle vendes. I 1995 blev der under det såkaldte "Road Management...

  2. Fluoridering af drikkevandet i Danmark?

    DEFF Research Database (Denmark)

    Arvin, Erik; Spliid, Henrik; Bruvo, M.;

    2010-01-01

    Første gang sammenhængen mellem caries (huller i tænderne) og fluoridindholdet i drikkevand blev diskuteret i vandværkskredse i Danmark var ved årsmødet i 1958. Her blev det oplyst, at fluorid i drikkevand beskytter mod caries, men man konstaterede også, at der nok ikke var stemning for fluorid......-tilsætning til drikkevandet (fluoridering). Siden da er emnet ikke taget op. Formålet med dette indlæg er at besvare spørgsmålene: 1. Er der behov for fluoridering af drikkevandet i Danmark? 2. Er der alternativer? Hvordan påvirker blødgøring af vand og andre vandbehandlingsmetoder dental caries hos børn og unge......? Som baggrund herfor vil vi redegøre for resultaterne af et netop afsluttet studium af sammenhængen mellem caries og drikkevandets sammensætning, specielt m.h.t. luoridindholdet og vandets calciumindhold (hårdhed). Undersøgelsen bekræfter, at fluorid i drikkevand i væsentlig grad beskytter mod caries...

  3. Udredning af xerostomi og hyposalivation

    DEFF Research Database (Denmark)

    Pedersen, Anne Marie Lynge; Dynesen, Anja Weirsøe; Jensen, Siri Beier

    2011-01-01

    Mundtørhed kræver grundig undersøgelse Xerostomi er ofte associeret til betydelig nedsat spytsekretion, men kan forekomme, uden at der objektivt kan påvises nedsat spytsekretion. Udredning af patienter, som klager over mundtørhed, bør således altid inkludere en omhyggelig anamnese, en detaljeret ...

  4. På sporet af fremtidens konkurrenceevne

    DEFF Research Database (Denmark)

    Boje Rasmussen, Martin Møller

    2013-01-01

    Michael Porter og Harvard Business School står bag nyt banebrydende initiativ, Social Progress Index, som måler et samfunds evne til at skabe livskvalitet for borgerne. Dette aktualiserer debatten om udviklingen af helt nye konkurrencemodeller. Der er tale om et valg mellem tre forskellige typer...

  5. Shortage of compressed air is expensive. Low pressure for end customers reduces efficiency and extends processing time; Druckluftmangel ist teuer. Niedriger Druck am Endverbraucher mindert die Leistung und verlaengert die Bearbeitungszeit

    Energy Technology Data Exchange (ETDEWEB)

    Stapel, A.G.

    2002-04-02

    The efficiency of compressed air tools decreases distinctly at 0,5 bar under normal pressure. Lower efficiency of a tool extends the processing time and low pressure in distribution network rises up energy cost. [German] - Schon 0,5 bar unter Nenndruck sinkt die Leistungsfaehigkeit vieler Druckluftwerkzeuge deutlich. - Die geringere Leistung eines Werkzeuges verlaengert auch die Arbeitszeit. - Zu niedriger Druck im Netz fuehrt zu deutlich hoeheren Energiekosten. (orig.)

  6. Empilhamento de ar e compressão torácica aumentam o pico de fluxo da tosse em pacientes com distrofia muscular de Duchenne Air stacking and chest compression increase peak cough flow in patients with Duchenne muscular dystrophy

    Directory of Open Access Journals (Sweden)

    Magneide Fernandes Brito

    2009-10-01

    Full Text Available OBJETIVO: Avaliar a eficiência da tosse através do uso de duas manobras manuais de auxílio à tosse. MÉTODOS: Foram selecionados 28 pacientes portadores de distrofia muscular de Duchenne em uso de ventilação mecânica não-invasiva noturna e CVF OBJECTIVE: To evaluate cough efficiency using two manually-assisted cough techniques. METHODS: We selected 28 patients with Duchenne muscular dystrophy. The patients were receiving noninvasive nocturnal ventilatory support and presented FVC values < 60% of predicted. Peak cough flow (PCF was measured, with the patient seated, at four time points: at baseline, during a spontaneous maximal expiratory effort (MEE; during an MEE while receiving chest compression; during an MEE after air stacking with a manual resuscitation bag; and during an MEE with air stacking and compression (combined technique. The last three measurements were conducted in random order. The results were compared using Pearson's correlation test and ANOVA with repeated measures, followed by Tukey's post-hoc test (p < 0.05. RESULTS: The mean age of the patients was 20 ± 4 years, and the mean FVC was 29 ± 12%. Mean PCF at baseline, with chest compression, after air stacking and with the use of the combined technique was 171 ± 67, 231 ± 81, 225 ± 80, and 292 ± 86 L/min, respectively. The results obtained with the use of the combined technique were significantly better than were those obtained with the use of either technique alone (F[3.69] = 67.07; p < 0.001. CONCLUSIONS: Both chest compression and air stacking techniques were efficient in increasing PCF. However, the combination of these two techniques had a significant additional effect (p < 0.0001.

  7. Case-Studie af Fredericia Battle 1849

    DEFF Research Database (Denmark)

    Konzack, Lars

    2015-01-01

    En gennemgang af hvordan oplevelsesøkomien fungerer diskursivt - med Fredericia Battle 1849 som case.......En gennemgang af hvordan oplevelsesøkomien fungerer diskursivt - med Fredericia Battle 1849 som case....

  8. Udvikling af systemleverancer, parametri og BIM

    DEFF Research Database (Denmark)

    Kortegaard, Per

    2016-01-01

    Seminaret rummede indlæg fra både nogle af projektets tidligere ph.d.-studerende og forskellige kompetente professionelle personer fra forskellige grene af praksis. Seminaret gav samlet et fint billede af status indenfor udviklingen af systemleverancer og deres anvendelse i relation til BIM (Buil...... (Building Information Modeling) nationalt som internationalt. Nærværende publikation og dens PDF-udgave rummer seminarets indlæg og illustrationer.......Seminaret rummede indlæg fra både nogle af projektets tidligere ph.d.-studerende og forskellige kompetente professionelle personer fra forskellige grene af praksis. Seminaret gav samlet et fint billede af status indenfor udviklingen af systemleverancer og deres anvendelse i relation til BIM...

  9. Politisk afmagt og udhuling af frihed

    DEFF Research Database (Denmark)

    Thomsen, Steen

    2015-01-01

    Vi oplever lige nu en politisk handlingslammelse som forudset af den liberale økonom von Hayek.......Vi oplever lige nu en politisk handlingslammelse som forudset af den liberale økonom von Hayek....

  10. Æstetisk tolkning af moderne landbrugslandskaber?

    DEFF Research Database (Denmark)

    Krarup, Jonna Majgaard

    2001-01-01

    Præsentation af del af igangværende ph.d.projekt, titel: landbrugeren som kulturlandskabsforvalter - AAA, DK. I projektet arbejdes der udfra en tese om naturopfattelse som af instrumentiel og formdannende karakter. Det moderne landbrugslandskabs ses således som fysisk og æstetisk udtryk for abstr......Præsentation af del af igangværende ph.d.projekt, titel: landbrugeren som kulturlandskabsforvalter - AAA, DK. I projektet arbejdes der udfra en tese om naturopfattelse som af instrumentiel og formdannende karakter. Det moderne landbrugslandskabs ses således som fysisk og æstetisk udtryk...... for abstrakte og kulturelt definerede holdninger af forholdet mellem menneske og natur - forvaltet af den moderne landbruger. I artiklen fokuseres der på et enkelt landskabselement og dets iboende muligheder for æstetisk erfaring og fortolkning....

  11. Sygeplejestuderendes brug af portfolio i klinisk undervisning

    DEFF Research Database (Denmark)

    Hjorth, Anne Charlotte Overgaard; Bruhn, Helle

    2014-01-01

    Brugen af portfolio var mangelfuld, men et udviklingsprojekt i samarbejde med den kommunale sygepleje motiverede både sygeplejestuderende og kliniske vejledere til at anvende læringsdelen af portfolio aktivt.......Brugen af portfolio var mangelfuld, men et udviklingsprojekt i samarbejde med den kommunale sygepleje motiverede både sygeplejestuderende og kliniske vejledere til at anvende læringsdelen af portfolio aktivt....

  12. Kortlægning af unge

    DEFF Research Database (Denmark)

    Skou, Carl Verner

    2009-01-01

    Computerprogram til Windows XP/Vista platformen til indberetning af unge under 18 år til registering af stofmisbrug og sociale data. Udgave: 1.0.1.1 Udgivelsesdato: 01-01-2009......Computerprogram til Windows XP/Vista platformen til indberetning af unge under 18 år til registering af stofmisbrug og sociale data. Udgave: 1.0.1.1 Udgivelsesdato: 01-01-2009...

  13. Udviklingen af rumopfattelsen 1600-2000

    DEFF Research Database (Denmark)

    Brock, Steen

    2010-01-01

    Hovedtræk af rumopfattelsens idehistorie fra Descartes til Wittgenstein med speciel vægt på Kant, værkbegrebet, modelbegrebet og den fænomenologiske opfattelse af rummet som handlingens sted......Hovedtræk af rumopfattelsens idehistorie fra Descartes til Wittgenstein med speciel vægt på Kant, værkbegrebet, modelbegrebet og den fænomenologiske opfattelse af rummet som handlingens sted...

  14. Måling af mineraluldsfibre i indeklimaet

    DEFF Research Database (Denmark)

    Nielsen, O.; Andersen, N.E.; Bredsdorff, P.;

    Rapporten beskriver resultaterne af målinger af luftbårne mineraluldsfibre, luftbårne ikke-mineraluldsfibre, luftbårent støv samt sedimenterede mineraluldsfibre i 105 lokaler med forskellige loftstyper. Resultaterne vil bl.a. kunne anvendes i forbindelse med vurdering af mulighederne for reduceri...

  15. Registrering af biometriske og biologiske personoplysninger

    DEFF Research Database (Denmark)

    Blume, Peter Erik; Herrmann, Janne Rothmar

    2009-01-01

    Med udgangspunkt i menneskeretsdomstolens Marper dom drøftes i artiklen indretningen af dansk rets regler om registrering af fingeraftryk og dna-profil med tilhørende biologisk materiale, og om dommen nødvendiggør ændringer af disse regler....

  16. Forskningsbibliotekernes bidrag til produktion af evidensbaseret viden

    DEFF Research Database (Denmark)

    Johannsen, Carl Gustav

    2012-01-01

    Artiklen indeholder en karakteristik af evidensbevægelsens metodemæssige grundlag, hvor det pointeres, at evidensbevægelsen er et forgrenet, internationalt samrabejde om produktion og formidling af systematiske reviews vedr. effektiviteten af offentlige indsatser, interventioner, som hovedformål....

  17. Regulering af jødiske kroppe

    DEFF Research Database (Denmark)

    Schleicher, Marianne

    2014-01-01

    på teori dels af Michel Foucault om, hvordan kultur sikrer sin egen overlevelse ved at indsamle viden om bl.a. kroppe med henblik på at regulere brugen af dem, dels af Judith Butler, der bl.a. forklarer, hvordan kultur trods alt er åben for såkaldt subversion, idet det bidrager til at udvide og...

  18. Registrering og Benchmarking af Modus 2 Forskning

    DEFF Research Database (Denmark)

    Duus, Henrik Johannsen; Jørgensen, Jens E.

    2004-01-01

    Fremvæksten af modus 2 forskning stiller krav om en revurdering af højere læreanstalters evaluerings- og meriteringspraksis. Den endimensionale prioritering af modus 1 forskning såvel som dennes ligeså endimensionale evaluering via publikationer må afvises som utidssvarende. Som en konsekvens her...

  19. Energioptimering af bæredygtighedscertificeringsprocesserne

    DEFF Research Database (Denmark)

    Christensen, Dorthe Holmberg; Carlsen, Mads; Alon, Shlomo Nevo

    2014-01-01

    Større fokus på bæredygtighedscertificeringer som DGNB har yderligere øget kompleksiteten af designet af bygninger. Introduktionen af teknologier som building information modelling (BIM) og proces metoder som integreret design proces (IDP) kan hjælpe med at reducere kompleksiteten og bedre...

  20. Modelanalyser af mobilitet og miljø

    DEFF Research Database (Denmark)

    Christensen, Linda; Gudmundsson, Henrik

    Begrebet bæredygtig transport diskuteres og ved hjælp af persontrafikmodellen ALTRANS belyses mulighederne for at fremme bæredygtig udvikling gennem en række scenarier. Desuden præsenteres en mere detaljeret analyse af ændringer i CO2-belastningen ved forbedring af den kollektive trafiks servicen...

  1. Dimensionering af indblæsning

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    1974-01-01

    Dimensionering af indblæsningsarmaturer og bestemmelse af luftfordeling i lokaler bygger traditionelt på kendskabet til isotermiske fristråler og vægstråler. Som det fremgår af skitserne i indholdsfortegnelsen, indleder vi også med dette emne. Derefter udsætter vi - skridt for skridt - de ideele...

  2. Fermentering af korn øger fordøjeligheden af næringsstoffer

    DEFF Research Database (Denmark)

    Pedersen, Anni Øyan; Jørgensen, Henry Johs. Høgh; Knudsen, Knud Erik Bach;

    2010-01-01

    Et fordøjelighedsforsøg har vist, at energiværdien af byg og hvede steg ved fermentering. Effekten var størst ved fermentering af byg, hvor fordøjeligheden af organisk stof for enden af tyndtarmen steg statistisk sikkert med 9 %. Ved fermentering af hvede steg fordøjeligheden af organisk stof...... statistisk sikkert med 3 %. Stigningen i energiværdien ved fermentering af korn kunne ikke vises ved foderanalyser (FEsv), hvilket viser, at in vitro-analyserne EFOS og EFOSi ikke kan anvendes til vurdering af effekten af fermentering. Fordøjeligheden af fosfor i foderblandinger baseret på byg eller hvede og...... tilskudsfoder steg statistisk sikkert ved fermentering af kornet. Der blev ikke tilsat mikrobiel fytase. Ved fermentering af byg steg fordøjeligheden af fosfor i foderblandingen fra 32 til 47 %, og ved fermentering af hvede steg fordøjeligheden af fosfor i blandingen fra 43 til 57 %. Fordøjeligheden af fosfor i...

  3. Undersøgelse af kommunernes administration af bygningsreglementets elevatorkrav

    DEFF Research Database (Denmark)

    Grangaard, Sidse

    få dispensationsansøgninger for elevator ved nybyggeri. Undersøgelsen tyder dog på, at nogle bygherrer og rådgivere er opmærksomme på kravet og i nogle tilfælde vælger at disponere bygningen, så der ikke stilles krav om elevator. Ved ombygning og tilbygning oplever langt over halvdelen af kommunerne...

  4. Trafikanalyser af et net af letbaner og BRT i Hovedstaden

    DEFF Research Database (Denmark)

    Nielsen, Otto Anker; Ingvardson, Jesper Bláfoss; Andersen, Jonas Lohmann Elkjær

    Denne rapport gennemgår et projekt for Region Hovedstaden, hvor letbanenet fra forårets opgave for Region Hovedstaden (Nielsen, Ingvardson & Andersen, 2013) blev detaljeret, viderebearbejdet og forbedret, hvorefter der er gennemført beregninger af forskellige varianter med OTM Trafikmodellen. Arb...... og sammenlignes med tidligere net og beregninger, der er blevet gennemført i Trængselskommissionens regi....

  5. Trials of the use of high pressure compressed air for coal winning in soutirage faces. Final report; Ensayo de arranque de carbon con aire comprimido de alta presion en explotaciones por sutiraje. Informe final

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    The company Hullera Vasco Leones (HVL) is trying to improve the results of its exploitations by means of soutirage (sublevel caving), looking for maximum vertical concentration of the product. The limitation of the present systems necessitates the use of other methods of breaking the coal block. For this reason, a trial of the high pressure compressed air blasting (DACAP) technique would appear to be appropriate. This offers the outstanding advantage of increasing the height of the coal obtained by soutirage. HVL has divided the investigation into two stages. Firstly, to study the feasibility study recommended the use of the Competidora method, using the DACAP technique for the soutirage, duplicating the distance between sublevels. The foreseen improvements are a cost reduction of 17% and an output increase of almost 9%. The trial stage of this operation started in the first six months of 1992 and results were established in relation to: working variables optimization, improvements in production and productivity, a better percentage of coal recovery and cost reductions. This document summarises the work done and the results obtained from the project.

  6. Måling af diskrimination på baggrund af etnisk oprindelse

    DEFF Research Database (Denmark)

    Jensen, Tina Gudrun; Weibel, Kristina; Tørslev, Mette Kirstine

    Denne rapport sætter fokus på, hvordan man kan måle diskrimination på baggrund af etnisk oprindelse. På baggrund af et studie af tidligere undersøgelser på området og relevant metodelitteratur, søger rapporten at udvikle metoder til valide målinger af diskrimination på baggrund af etnisk oprindel...

  7. Halvering af dagpengeperioden og akutpakken

    DEFF Research Database (Denmark)

    Nilsson, Klara; Holt, Helle

    Formålet med denne undersøgelse er at give et øjebliksbillede af jobcentrenes og a-kassernes beskæftigelsesindsats her og nu. Gennem en række kvalitative interview med medarbejdere fra jobcentre og a-kasser belyses det, hvordan henholdsvis jobcentre og a-kasser har håndteret halveringen af...... at finde et job, hvilket blandt andet har betydet en tidligere og intensiveret indsats overfor de ledige. Den særlige indsats har derfor bidraget med et større fokus og sammenhæng i indsatsen for den enkelte borger gennem blandt andet en personlig jobformidler og fællessamtaler mellem den ledige, a...

  8. Ledelsesroller i globalisering af cleantech

    DEFF Research Database (Denmark)

    Knudsen, Poul Frøjk; Tambo, Torben

    2011-01-01

    Cleantech anses i de fleste industrialiserede lande for den nye vækstbølge, der både skal fastholde arbejdspladser og beskæftigelse og også redde miljøet. Danmark har været early-mover på vindkraft. Aktiv ledelse har til dato fastholdt et forspring. Denne aktive ledelse har sikret anvendelse af...

  9. Vaccination af slagtekalve mod BRSV

    DEFF Research Database (Denmark)

    Graumann, Anne Mette; Larsen, Lars Erik

    2009-01-01

    Rspiratory Suncytial Virus) blev fundet til at være den typisk fundne virus, der forårsager lungebetændelse. Vacciner imod BRSV er tilgængelige på markedet, men de er aldrig blevt afprøvet systematisk under danske forhold. Formålet med dette forsøg er at undersøge effekten af to forskellige...

  10. Brug af alternativ isolering i Finland og Sverige

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place

    2001-01-01

    Resume af rapport om anvendelse af alternative isoleringsmaterialer i Finland og Sverige, udarbejdet af SBI under Energistyrelsens udviklingsprogram "Miljø- og arbejdsmiljøvenlig isolering".......Resume af rapport om anvendelse af alternative isoleringsmaterialer i Finland og Sverige, udarbejdet af SBI under Energistyrelsens udviklingsprogram "Miljø- og arbejdsmiljøvenlig isolering"....

  11. Didaktisk design af et pervasive learning game

    DEFF Research Database (Denmark)

    Oldenskov, Joakim; Westergren, Jens; Frank, Anders Bredahl

    2010-01-01

    Projektet er et studie i det teoretiske grundlag for, og en empirisk undersøgelse, af en prototype for et didaktisk design af et pervasive learning game. Der arbejdes overordnet med udviklingen af et didaktisk design af et læringsspil som kombinerer mobile teknologier, det fysiske rum og eleverne...... game med en analyse af legen og motivationen iboende spillet. I det læringsteoretiske felt inddrages og diskuteres forskellige tilgange til læring og pervasive games, som alle repræsenterer et socialkonstruktivistisk syn på læring. Det didaktiske design danner grundlag for et prototypedesign af et...... spilkoncept, hvor remediering og it-kompetencer inddrages som vigtige teoretiske faktorer. Undersøgelsesdesignet er rettet mod elever i Folkeskolen igennem brugen af fokusgruppeinterviews, og dataindsamlingen er foretaget med video. Eleverne udtrykker sig i undersøgelsen klart omkring konceptets...

  12. Power plant including an exhaust gas recirculation system for injecting recirculated exhaust gases in the fuel and compressed air of a gas turbine engine

    Science.gov (United States)

    Anand, Ashok Kumar; Nagarjuna Reddy, Thirumala Reddy; Shaffer, Jason Brian; York, William David

    2014-05-13

    A power plant is provided and includes a gas turbine engine having a combustor in which compressed gas and fuel are mixed and combusted, first and second supply lines respectively coupled to the combustor and respectively configured to supply the compressed gas and the fuel to the combustor and an exhaust gas recirculation (EGR) system to re-circulate exhaust gas produced by the gas turbine engine toward the combustor. The EGR system is coupled to the first and second supply lines and configured to combine first and second portions of the re-circulated exhaust gas with the compressed gas and the fuel at the first and second supply lines, respectively.

  13. Kvalitetssikring af Ul prober på baggrund af protokol til vurdering af tekniske fantom billeder

    DEFF Research Database (Denmark)

    Vernegreen, Susanne

    2013-01-01

    fordel sorteres fra i en revidering af protokollen. Jeg havde valgt at medtage dem, da de indgik i den oprindelige CIRS protokol, og det kan i en startfase være en fordel at have flere målinger at holde sig til. Min vurdering er dog at denne fordel ikke opvejer det øgede tidsforbrug. Der er dog nogle...... ikke muligt at undgå subjektivitet i forbindelse med måling og vurdering af de tekniske fantombilleder, da disse foretages manuelt. Det er derfor vigtigt at foretage flere målinger, og måske også oftere målinger end hvis målingerne var objektive. Flere og oftere målinger tager tid, og kan gå ud over...

  14. Modellering af naturlig ventilation og natkøling- ved hjælp af ringmetoden

    DEFF Research Database (Denmark)

    Jensen, Rasmus Lund

    baseret på ringmetoden [Loop Equation Method] med tilhørende regulering blev implementeret i det termiske simuleringsprogram BSim. 1.3 Beregning af natkøling Ved beregning af effekten af natkøling benyttes primært simple overslagsmodeller eller termiske simuleringsprogrammer. Hvor de simple modeller er...... samspillet med bygningens termiske forhold • Udvikle model til beregning af effekten ved natkøling med naturlig ventilation 1.1 Beregning af naturlig ventilation Da dette arbejde startede og stadig i dag er der kun ganske få bygningssimuleringsprogrammer der kan tage hensyn til både naturlig ventilation og...... til beregning af naturlig ventilation. 1.2 Multizone model En gennemgang af litteraturen for beregning af naturlig ventilation blev gennemført med henblik på at opstille en multizone model. To forskellige måder til opstilling af ligningssystemet blev identificeret, Knudemetoden og Ringmetoden. Det...

  15. Forekomst af resistente bakterier og forbrug af antibiotika til hunde

    DEFF Research Database (Denmark)

    Pedersen, Karl; Pedersen, Kristina; Jensen, Helene;

    2007-01-01

    ), Pasteurella multocida (n=25), Bordetella bronchiseptica (n=14), Proteus spp. (n=29), og E. coli (n=449). I undersøgelsen anvendtes data fra VetStat databasen. Størstedelen af de antibiotika, der bruges til hunde er bredspektrede. Penicilliner med udvidet spektrum, cephalosporiner samt sulphonamider...... penicillin, 30,2% overfor fucidin og 27,9% overfor macrolider. E. coli isolaterne var mest resistente overfor ampicillin, sulphonamider, trimethoprim, tetracykliner og streptomycin, og anhæmolytiske isolater var oftere resistente overfor tetracykliner, trimethoprim og chloramphenikol end hæmolytiske isolater...

  16. Compressed gas fuel storage system

    Energy Technology Data Exchange (ETDEWEB)

    Wozniak, John J. (Columbia, MD); Tiller, Dale B. (Lincoln, NE); Wienhold, Paul D. (Baltimore, MD); Hildebrand, Richard J. (Edgemere, MD)

    2001-01-01

    A compressed gas vehicle fuel storage system comprised of a plurality of compressed gas pressure cells supported by shock-absorbing foam positioned within a shape-conforming container. The container is dimensioned relative to the compressed gas pressure cells whereby a radial air gap surrounds each compressed gas pressure cell. The radial air gap allows pressure-induced expansion of the pressure cells without resulting in the application of pressure to adjacent pressure cells or physical pressure to the container. The pressure cells are interconnected by a gas control assembly including a thermally activated pressure relief device, a manual safety shut-off valve, and means for connecting the fuel storage system to a vehicle power source and a refueling adapter. The gas control assembly is enclosed by a protective cover attached to the container. The system is attached to the vehicle with straps to enable the chassis to deform as intended in a high-speed collision.

  17. Gennemgang af den danske samfundsregulering

    DEFF Research Database (Denmark)

    Falch, Morten

    investeringer hos en bred række af markedsaktører’1. Midlet til at opnå dette mål har været at skabe et regelsæt der gør det lettere for nye virksomheder at komme ind på det nye telemarked, og konkurrere på lige fod med TDC. Herudover, har man hjulpet de nye operatører på vej gennem en såkaldt asymmetrisk...

  18. Etablering af global distribueret produktion

    DEFF Research Database (Denmark)

    Sørensen, Brian Vejrum; Johansen, John; Riis, Jens Ove

    2007-01-01

      Mange danske produktionsvirksomheder står over for en ny æra, som handler om at udvikle og styre globale distribuerede produktionsenheder og det netværk, disse til sammen danner. Interviews med top- og mellemledere i 15 danske produktionsvirksomheder med varierende størrelse og internationalt...... erfaringsgrundlag viser, at der i begyndelsen af globaliserings- og produktionsudflytningsprocessen isoleret set er stor fokus på omkostningsminimering - nogle gange kædet sammen med ønsker om markedsekspansion, men også at fokus og argumenterne ofte ændrer sig over tid og efterhånden bliver mere nuanceret. Ved...

  19. Effekter af koordineret hjerneskaderehabilitering. Et systematisk litteraturreview

    DEFF Research Database (Denmark)

    Glintborg, Chalotte; Hansen, Tia G. B.

    Forskningsprojekt udvikler ny definition af begrebet koordination Som et led i forskningsprojektet ”Bio-psyko-sociale effekter af koordineret hjerneskaderehabilitering” er der udviklet en ny definition af koordinationsbegrebet. Forskningsprojektet ”Bio-psyko-sociale effekter af koordineret...... senhjerneskadeområdet – initiativer, der skal fremme en sammenhængende og helhedsorienteret rehabiliteringsindsats. Men hvad dækker begrebet koordination egentlig over? Det har et nyt forskningsprojekt set på og kommer med et bud på en ny definition. Dansk definition mangler Indholdet i koordination har været upræcist...... beskrevet. Der er ingen klar dansk definition af koordination. Begrebet bliver ofte brugt inkonsistent, og koordination er meget forskelligt tilrettelagt. Derfor kan man ikke generelt dokumentere, om koordinatorfunktioner er en sikker vej til forbedring af komplekse rehabiliteringsforløb. Sundhedsstyrelsen...

  20. Modeling and Verification of Hybrid Energy Storage System Based on Micro Compressed Air Energy Storage%基于微型压缩空气储能的混合储能系统建模与实验验证

    Institute of Scientific and Technical Information of China (English)

    王成山; 武震; 杨献莘; 张书槐; 刘一欣

    2014-01-01

    The micro compressed air energy storage system is a new type of energy storage systems capable of being combined with flywheel to form a hybrid energy storage system.The structure and principle of a hybrid energy storage system based on micro compressed air energy storage is described.The governor system model of micro compressed air energy storage is proposed based on the experimental data,which simulates the dynamics of pressure,temperature,valve,and turbine and so on.Finally,a comparison between experimental data and simulation results is given to verify the applicability and effectiveness of the proposed model. This work is supported by National Basic Research Program of China(973 Program)(No.2009CB219700).%微型压缩空气储能是一种新型的储能技术,可以与飞轮等组成混合储能系统。文中介绍了基于微型压缩空气储能的混合储能系统的结构及工作原理,根据现有设备的实验结果提出了压缩空气储能原动部分的数学模型,包括压缩空气压力、温度、阀门、透平等环节,并通过拟合的方法进行参数辨识。最后,搭建了混合储能系统的仿真算例,并通过仿真与实验数据的对比验证了模型的适用性和有效性。

  1. Offentliggørelse af kursrelevante oplysninger

    DEFF Research Database (Denmark)

    Werlauff, Erik; Schaumburg-Müller, Peer

    2013-01-01

    Artiklen analyserer, særligt på baggrund af EU-Domstolens dom af 28. juni 2012 i C-19/11, Daimler AG, hvilken betydning en række mellemliggende trin, der fører frem til en kursrelevant og offentliggørelsespligtig begivenhed, har for tidspunktet for indtrædelsen af pligten til offentliggørelse. De...

  2. Afgivelse af formaldehyd fra byggevarer og forbrugerprodukter

    DEFF Research Database (Denmark)

    Kolarik, Barbara; Gunnarsen, Lars; Funch, Llis Winther

    Rapporten præsenterer resultatet af en undersøgelse af formaldehydafgivelse fra 22 mulige kilder i indeklimaet. Undersøgelsen er gennemført for om muligt at finde årsagen til de høje koncentrationer af formaldehyd i indeluften, der blev fundet i enkelte danske boliger under en foregående undersøg...

  3. Motivation af den Kreative Sælger

    OpenAIRE

    Sørensen, Mikkel Vallentin; Floor, Jeppe Hjelmsted

    2012-01-01

    Projektet tager udgangspunkt i motivationen af danske sælgere. Med inspiration fra den positive psykologiske videnskab, udfordres eksisterende motivationsredskaber, med henblik på at motivere den enkelte medarbejder til at yde et bedre stykke arbejde for virksomheden. Daniel Pink, Bruno Frey og Frederick Herzberg danner det teoretiske grundlag for opgaven, og problemstillingen undersøges gennem en sammenholdelse af deres teorier med empirisk materiale i en fænomenologisk tilgang. Rapporten af...

  4. Praktik - set i lyset af billedkunstfaget

    DEFF Research Database (Denmark)

    Buhl, Mie; Skov, Kirsten; Meisner Christensen, Kirsten

    Kamelgruppen har vi været optaget af at pege på relevante temaer for udvikling af billedfaget og forandring i uddannelsen af kommende lærere. Foråret 2004 præsenterede gruppens medlemmer papers på symposiet 'Visual culture in education' på kongressen på Nordisk Forening for Pædagogisk forskning i Reykjavik...

  5. En kritisk analyse af Leviathan & Samfundspagten

    OpenAIRE

    Bjelobrk, Aleksandar

    2006-01-01

    I denne rapport undersøges de politiske filosoffer Thomas Hobbes’ (1588-1679) og Jean-Jacques Rousseaus (1712-1778) udgaver af kontraktteorien. Med udgangspunkt i Leviathan del 1, Of Man og del 2, Of Common-Wealth af Thomas Hobbes (Hobbes 1991, oprindelig udgivet 1651) og Samfundspagten af Jean-Jacques Rousseau (Rousseau 1987, oprindelig udgivet 1762) klarlægges inkonsisten i deres teorier gennem to separate analyser. Med udgangspunkt i den fundne inkonsistens foretages en komparativ analyse,...

  6. Metodebeskrivelse for evaluering af arkitektonisk kvalitet

    DEFF Research Database (Denmark)

    Beim, Anne

    2000-01-01

    Artiklen indgår i en større publikation som er en vejledning i evaluering af boligbebyggelsers standard og kvalitet. Vejledningen er bygget op over et evalueringskoncept, der primært er tilrettelagt med henblik på evaluering af (almene) boligbebyggelser og er udarbejdet til vurdering af 10...... forsøgsbyggerier inden for Erhvervsfremmestyrelsens og By - Boligministeriets udviklingsinitiativ ' Proces og Produktudvikling i byggeriet' - det såkaldte PPB- program....

  7. Danskernes brug af nyhedsmedier: et nyt landkort

    DEFF Research Database (Denmark)

    Schrøder, Kim Christian

    2010-01-01

    Artiklen fremlægger første del af en analyse, der på en ny måde kortlægger danskernes brug og oplevelse af nyheder i det medialiserede samfund, på tværs af de forskellige – traditionelle og digitale - medieplatforme og genrer. Teoretisk er undersøgelsen forankret i offentlighedsteorien og den beg...

  8. Konceptuelt design og udvikling af Intergomus

    DEFF Research Database (Denmark)

    Ellebæk, P.; Pedersen, T.; Stendal, Karsten;

    1999-01-01

    Denne rapport gennemgår udviklingsforløbet af et træningsapparat til genoptræning af læderede fingre. Rapporten omhandler kun den mekaniske del af udstyret. Opgaven er blevet løst i samarbejde med Ergoterapien på Køge Amtssygehus, Procare, Centret forAvanceret Teknologi og flere afdelinger på RIS...

  9. Opstilling af ventilationsarmaturer i CFD-beregninger

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    2009-01-01

    Opstilling af armaturer i CFD-beregninger er et område, hvor ventilationsbranchen skal tilføre CFD-metoderne en specialviden, som ikke på forhånd er indlagt i programmerne. I artiklen bringes nogle eksempler på specificering af en indblæsningsåbning......Opstilling af armaturer i CFD-beregninger er et område, hvor ventilationsbranchen skal tilføre CFD-metoderne en specialviden, som ikke på forhånd er indlagt i programmerne. I artiklen bringes nogle eksempler på specificering af en indblæsningsåbning...

  10. Omsætning af fast ejendom

    DEFF Research Database (Denmark)

    Edlund, Hans Henrik

    Bogen er en systematisk gennemgang af lov om omsætning af fast ejendom, der regulerer ejendomsmægleres virke. Følgende emner er bl.a. behandlet: Hvem kan drive ejendomsmæglervirksomhed og ejendomsmæglernes pligter og ansvar.......Bogen er en systematisk gennemgang af lov om omsætning af fast ejendom, der regulerer ejendomsmægleres virke. Følgende emner er bl.a. behandlet: Hvem kan drive ejendomsmæglervirksomhed og ejendomsmæglernes pligter og ansvar....

  11. Prøvetagning af grundvand

    DEFF Research Database (Denmark)

    Sørensen, Inga

    Bogen fokuserer på prøveatgning af grundvand og drikkevand til forskellige formål såsom undersøgelse af forurenede grunde, grundvandsmonitering samt produktion af drikkevand. Da grundvand i sagens natur findes under jordoverfladen, beskriver bogen også væsentlige forhold om hydrogeologi og grundv...... grundvandskemi i det omfang, disse forhold har betydning for den praktiske prøvetagning. Der redegøres også for de forskellige typer af pumper og udstyr samt emballage til vandprøver inklusive fordele og ulemer ved de forskellige typer....

  12. NIR optimerer produktionen af gammeldags modnede sild

    DEFF Research Database (Denmark)

    Svensson, Vibeke Tølbøl; Bro, Rasmus; Nielsen, Henrik Hauch;

    2005-01-01

    Måling med nærinfrarødt (NIR) lys er et godt supplement til de nuværende metoder til at følge modningen af sild saltede i tønder. Det viser resultaterne af et forskningsprojekt udført i samarbejde mellem Lykkeberg A/S, Danmarks Fiskeriundersøgelser og Den Kgl Veterinær- og Landbohøjskole. Ved hjælp...... af avanceret matematik er det nemt og hurtigt at bestemme modningsgraden af sild direkte fra en NIR måling....

  13. Partial transparency of compressed wood

    Science.gov (United States)

    Sugimoto, Hiroyuki; Sugimori, Masatoshi

    2016-05-01

    We have developed novel wood composite with optical transparency at arbitrary region. Pores in wood cells have a great variation in size. These pores expand the light path in the sample, because the refractive indexes differ between constituents of cell and air in lumen. In this study, wood compressed to close to lumen had optical transparency. Because the condition of the compression of wood needs the plastic deformation, wood was impregnated phenolic resin. The optimal condition for high transmission is compression ratio above 0.7.

  14. Towards Natural Transition in Compressible Boundary Layers

    Science.gov (United States)

    2016-06-29

    UNIT NUMBER 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 16. SECURITY CLASSIFICATION OF: 19b. TELEPHONE NUMBER (Include area code) The public reporting...4] Leandro F. Bergamo, Elmer M. Gennaro, Vassilis Theofilis, and Marcello A.F. Medeiros. Compressible modes in a square lid-driven cavity. Aerospace...Fluid Mechanics, 724:480–509, 6 2013. [68] H. Schlichting. Zur Entstehung der Turbulenz bei der Plattenströmung. In Math . Phys. Klasse, pages 182–208

  15. Hypervirkelig(?). Studier af ungdom, skole og modernitet i udkanten af Kathmandu

    DEFF Research Database (Denmark)

    Madsen, Ulla Ambrosius

    2010-01-01

    Med udgangspunkt i etnografiske studier af ungdom og skoleliv i udkanten af Kathmandu, analyserer artiklen samspillet mellem 'det moderne', uddannelse og identitet blandt unge der lever i udkanten af den globale periferi.I modsætning til studier der beskæftiger sig med om og hvordan uddannelse bi...... fremtiden. Teoretisk trækker deres på begreber og positioner fra postmoderne metodologiskeog filosofiske orienteringer - repræsenteret blandt andre af Popkewitz, Maclure og Baudrillard....

  16. Midler til lindring af mundtørhed og stimulation af spytsekretion

    DEFF Research Database (Denmark)

    Dynesen, Anja Weirsøe; Pedersen, Anne Marie Lynge; Jensen, Allan Bardow;

    2013-01-01

    effekt. I relation til risikoen for at udvikle caries, der er forhøjet hos den mundtørre patient, er det dog væsentligt at anbefale produkter uden sukker. Ligesom produktets indhold af syre og dermed det erosive potentiale er af betydning i forhold til udviklingen af dentale erosioner. Systemisk...

  17. Process for regeneration of a soot particle filter situated in the exhaust pipe of an air-compressing internal combustion engine. Verfahren zur Regeneration eines in der Abgasleitung einer luftverdichtenden Brennkraftmaschine angeordneten Russpartikelfilters

    Energy Technology Data Exchange (ETDEWEB)

    Abthoff, J.; Schuster, H.D.; Langer, H.J.; Strohmer, E.; Gabler, R.; Schulte, R.

    1991-05-08

    A process for the regenration of a soot particle filter situated in the exhaust pipe of an air-compressing injection internal combustion engine by burning off the soot particles is described. A device to control the suction pipe cross section depending on the load and speed is provided in the suction pipe. To prevent damage to the soot filter when changing to thrust operation of the internal combustion engine, it is proposed to move the device to control the suction air pipe cross section directly after a change to thrust operation of the internal combustion engine to a position reducing the pipe crosss ection to a minimum and then to move it continuously to its open position.

  18. 压空缓冲罐和真空缓冲罐容积的确定%Determination of Volumes for Compressed Air Buffer Tank and Vacuum Buffer Tank

    Institute of Scientific and Technical Information of China (English)

    王绍宇

    2015-01-01

    介绍了制药行业压空缓冲罐和真空缓冲罐容积的计算公式,并结合实例对储气罐、稳压罐的容积计算方法、组合方式进行了讨论,同时对缓冲罐的气液分离效果及设备直径的确定给出了计算方法。%In this article, the formulas for calculating the volumes of compressed air buffer tank and vacuum buffer tank used in pharmaceutical industry were introduced. Combined with practical examples, the methods of calculating the volumes of air storage tank and pressure stability tank and tank combination forms were discussed. Meanwhile, the calculating methods for determining the effect of gas-liquid separation and the diameter of vessel were provided.

  19. Barrierer for ibrugtagning af videooptaget universitetsundervisning

    Directory of Open Access Journals (Sweden)

    Pernille Rattleff

    2009-06-01

    Full Text Available Danmarks Pædagogiske Universitetsskole ved Aarhus Universitet har siden 2006 eksperimenteret med systematisk videooptagelse og -streamning af undervisning på udvalgte kandidat- og masteruddannelser. De studerende er begejstrede for denne praksis og de muligheder, dette giver de studerende for at understøtte deres læring. Men selvom de studerende har vist sig at bruge den videostreamede undervisning på en endog særdeles hensigtsmæssig måde, har der, både blandt studerende og især blandt underviserne, været modstand mod dels overhovedet at optage, dels at gøre optagelserne af undervisningen offentligt tilgængelige for studerende og andre interesserede. Der kan således iagttages nogle barrierer i forhold til ibrugtagning af videooptaget undervisning på universitetsniveau, idet underviserne for en umiddelbar betragtning tilsyneladende for det første har nogle forbehold af psykologisk, for det andet af juridisk karakter og for det tredje af organisatorisk art. Et af de centrale spørgsmål i denne forbindelse synes således at være, om optagelse af undervisning muliggør en ledelsesmæssig evaluering af den enkelte undervisers undervisningspraksis. Et andet centralt spørgsmål er tilsyneladende, om optagelse af undervisningen, der muliggør genbrug, gør underviserne overflødige. Forfatterne til denne artikel er imidlertid af den opfattelse, at undervisernes modstand følger af en anden, og mere grundlæggende, diskrepans, nemlig diskrepansen mellem det at forske og det at undervise. Efter en indledende begrebsafklaring, præsenterer forfatterne i denne artikel erfaringerne med tilbud af videostreamet og podcastet universitetsundervisning til studerende på Danmarks Pædagogiske Universitetsskole med henblik på en diskussion af de potentialer og især de barrierer, der kan iagttages i forhold til en mere systematisk, large-scale brug af castet universitetsundervisning. I forlængelse heraf formulerer forfatterne desuden en mulig

  20. Grade-2 Teflon (AF1601) PCF for optical communication using 2D FDTD technique: a simplest design

    Science.gov (United States)

    Muduli, N.; Achary, J. S. N.; Padhy, Hemanta ku.

    2016-04-01

    A nonlinear ytterbium-doped rectangular proposed PCF structure of inner and outer cladding is used to analyze effective mode field area (Aeff), nonlinear coefficient (γ), dispersion (D), and confinement loss (CL) in a wide range of wavelength. The fabrication of PCF structure is due to different size doped air hole, pitch, and air hole diameter in a regular periodic geometrical array fashion. The various property of PCF structure such as mode field area, nonlinear coefficient, dispersion, and confinement loss are analyzed by implementing 2D FDTD technique. The above PCF property investigated using suitable parameters like Λ1, ?, ?, and ? in three different situations is discussed in simulation. The high nonlinear coefficient and dispersion property of PCF structure are tailored by setting the cladding parameter. However, highly nonlinear fibers with nonzero dispersion at the wavelength of 1.55 μm are very attractive for a range of optical communication application such as laser amplifier, pulse compression, wavelength conversion, all optical switching, and supercontinuum generation. So our newly proposed ytterbium-doped PCF seems to be most suitable exclusively for supercontinuum generation and nonlinear fiber optics. Finally, it is observed that ytterbium-doped Teflon (AF1601) PCF has more nonlinear coefficient (γ(λ) = 65.27 W-1 km-1) as compared to pure silica PCF (γ(λ) = 52 W-1 km-1) design to have same mode field area (Aeff) 1.7 μm2 at an operating wavelength of 1.55 μm.

  1. Design of Marine Compressed Air Operation Training System with Virtual and Physical Combination%一种虚实结合的船舶压缩空气操作训练系统设计

    Institute of Scientific and Technical Information of China (English)

    邹文俊; 林洪贵; 孙美娜

    2015-01-01

    Marine power plant operation training system in shipping colleges has the disadvantages of large area, the high cost and the lack of real ship environment. Aimed at this problem,and taking marine compressed air system as an example, a combination of virtual and physical marine power plant operation training system is designed. The scene roaming and virtual operation function of the marine compressed air system is realized by Unity3D, the control task of the air compressor is completed by PLC control technology, and the problem of data communication between PLC Controllers and Unity3D is solved. Finally, the paper achieves the purpose of controlling the virtual air compressor through the physical control box.%针对航运院校采用真实船舶动力设备系统操作训练存在占地面积大、成本高且缺少实船环境的缺点,本文以船舶压缩空气系统为例设计出一种虚实结实的动力设备操作训练系统,建立了压缩空气系统的三维实体模型和设备的数学模型,通过 Unity3D 实现了船舶压缩空气系统的场景漫游和虚拟操作功能,采用PLC控制技术实现了空压机组的控制功能,解决了PLC控制器与Unity3D之间数据交互问题,最终实现了通过实物控制箱控制虚拟的空压机组的目的.

  2. Opportunistic Relay Selection in Multicast Relay Networks using Compressive Sensing

    KAUST Repository

    Elkhalil, Khalil

    2014-12-01

    Relay selection is a simple technique that achieves spatial diversity in cooperative relay networks. However, for relay selection algorithms to make a selection decision, channel state information (CSI) from all cooperating relays is usually required at a central node. This requirement poses two important challenges. Firstly, CSI acquisition generates a great deal of feedback overhead (air-time) that could result in significant transmission delays. Secondly, the fed back channel information is usually corrupted by additive noise. This could lead to transmission outages if the central node selects the set of cooperating relays based on inaccurate feedback information. In this paper, we introduce a limited feedback relay selection algorithm for a multicast relay network. The proposed algorithm exploits the theory of compressive sensing to first obtain the identity of the “strong” relays with limited feedback. Following that, the CSI of the selected relays is estimated using linear minimum mean square error estimation. To minimize the effect of noise on the fed back CSI, we introduce a back-off strategy that optimally backs-off on the noisy estimated CSI. For a fixed group size, we provide closed form expressions for the scaling law of the maximum equivalent SNR for both Decode and Forward (DF) and Amplify and Forward (AF) cases. Numerical results show that the proposed algorithm drastically reduces the feedback air-time and achieves a rate close to that obtained by selection algorithms with dedicated error-free feedback channels.

  3. Wellhead compression

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, Joe [Sertco Industries, Inc., Okemah, OK (United States); Vazquez, Daniel [Hoerbiger Service Latin America Inc., Deerfield Beach, FL (United States); Jacobs, Denis Richard [Hoerbiger do Brasil Industria de Equipamentos, Cajamar, SP (Brazil)

    2012-07-01

    Over time, all wells experience a natural decline in oil and gas production. In gas wells, the major problems are liquid loading and low downhole differential pressures which negatively impact total gas production. As a form of artificial lift, wellhead compressors help reduce the tubing pressure resulting in gas velocities above the critical velocity needed to surface water, oil and condensate regaining lost production and increasing recoverable reserves. Best results come from reservoirs with high porosity, high permeability, high initial flow rates, low decline rates and high total cumulative production. In oil wells, excessive annulus gas pressure tends to inhibit both oil and gas production. Wellhead compression packages can provide a cost effective solution to these problems by reducing the system pressure in the tubing or annulus, allowing for an immediate increase in production rates. Wells furthest from the gathering compressor typically benefit the most from wellhead compression due to system pressure drops. Downstream compressors also benefit from higher suction pressures reducing overall compression horsepower requirements. Special care must be taken in selecting the best equipment for these applications. The successful implementation of wellhead compression from an economical standpoint hinges on the testing, installation and operation of the equipment. Key challenges and suggested equipment features designed to combat those challenges and successful case histories throughout Latin America are discussed below.(author)

  4. Compressive beamforming

    DEFF Research Database (Denmark)

    Xenaki, Angeliki; Mosegaard, Klaus

    2014-01-01

    Sound source localization with sensor arrays involves the estimation of the direction-of-arrival (DOA) from a limited number of observations. Compressive sensing (CS) solves such underdetermined problems achieving sparsity, thus improved resolution, and can be solved efficiently with convex...

  5. Environmental assessment of speeding up use of particle filters on passenger cars and vans. Air quality and population exposure for PM{sub 2.5}; Miljoevurdering af fremskyndelse af partikelfiltre pae person- og varebiler. Luftkvalitet og befolkningseksponering for PM{sub 2.5}

    Energy Technology Data Exchange (ETDEWEB)

    Solvang Jensen, S.; Ketzel, M. [DMU, Afd. for Atmosfaerisk Miljoe (Denmark)

    2006-11-15

    New stringent European Union emission standards for particles are expected to be implemented around 2010 for diesel-powered passenger cars and vans. Provided that such standards are agreed upon diesel-powered passenger cars and vans are expected to be equipped with particle filters that effectively will remove particle emissions. Against this background, the Danish Environmental Assessment Institute wanted to carry out a cost-benefit analysis of a scenario where the emission standards came into force in 2007 instead of 2010. The objective of the project is to assess the effects on particle emissions and air quality of PM{sub 2.5} (particles less than 2.5 micrometer) of moving forward the emission standards for passenger cars and vans. An assessment of a scenario is carried out that assumes that all new diesel-powered passenger cars and vans entering the vehicle fleet during January 1st, 2007 and December 31st, 2009 will be equipped with particle filters. The National Environmental Research Institute has carried out this assessment. (au)

  6. Måling af stress hos mink

    DEFF Research Database (Denmark)

    Malmkvist, Jens

    2010-01-01

    temadagen præsenteres nye resultater og metoder til at vurdere stress hos mink. I en metode måles koncentrationen af nedbrydningsprodukter af hormonet cortisol i gødning fra mink. Der er en række fordele ved denne metode, frem for blodprøvetagning. Forsøg viste, at hovedparten af cortisol udskilles i fæces...... (83 %) frem for i urin (17 %), samt at omsætningen af radioaktivt mærket cortisol ikke er forskellig mellem mink med hhv. lav og høj forekomst af stereotypi. Denne viden kan bruges til bedre at forstå koblingen f.eks. unormal adfærd og stress hos mink.......Sammendrag Stress indgår som et element ved vurdering af dyrevelfærd. Endvidere kan stress mål anvendes i undersøgelser, hvor forskellige typer af avl, burmiljø og pasning af mink sammenlignes. Men hvad er stress egentlig og hvordan måles det? Er unormal adfærd koblet til stress hos mink? På...

  7. Sundhedspleje - Studier af en normaliserende praksis

    DEFF Research Database (Denmark)

    Pedersen, Oline

    2013-01-01

    Phd.-afhandling Afhandlingen er en analyse af sundhedsplejens praksis. Dener udført på baggrund af etnografisk feltarbejde i sundhedsplejen (suppleret med interviews). Afhandlingen har tre undersøgelsesspørgsmål: Hvordan formidles normalitet i sundhedsplejens praksis? Hvilke former for normalitet...

  8. Tema 1: Programmering af robotenheder i grundskolen

    Directory of Open Access Journals (Sweden)

    Stine Ejsing-Duun

    2016-01-01

    Full Text Available I denne artikel undersøger vi potentialerne for at lære matematik gennem programmering af robotter. Vi foreslår en model med tre indbyrdes afhængige læringspotentialer, som programmering fordrer. Det omfatter elevens evne til at; (1 tænke i algoritmer, (2 producere viden og artefakter gennem brug af matematik og (3 foretage abstraktion og indkapsling. Programmering er blevet en del af grundskolens læringsmål i flere lande. I Danmark er programmering et læringsmål i forenklede fælles mål for Fysik/Kemi og desuden en del af den nationale undervisningsvejledning for matematik. En analyse af potentialerne i at anvende programmering i forbindelse med disse fag er derfor væsentlig. I denne artikel fokuserer vi på samspillet mellem matematik og programmering gennem litteraturstudier og analyse af empiriske situationer fra undervisning i programmering af LEGO Mindstorms. Teoretisk anvendes den instrumentelle tilgang til teknologi i matematikundervisning. Analysen viser en række måder, hvorpå didaktisk opmærksomhed på epistemisk forhandling kan understøtte læring af matematik gennem programmering.

  9. Grønland stiger af havet

    DEFF Research Database (Denmark)

    Laursen, Steen; Khan, Shfaqat Abbas

    2012-01-01

    En af de varme sommernyheder er, at Grønlands bjergtinder stiger mod himmelen i takt med, at indlandsisen tynder ud. Det viser dansk forskning, som bliver bakket op af amerikanske målinger fra Nasa. Newton har besøgt Nasa på Grønland og interviewet den danske forsker bag de nye resultater....

  10. Økonomisk Vurdering af Arbejdsulykker

    DEFF Research Database (Denmark)

    Rikhardsson, Pall M.; Mogensen, Birgitte; Ravn, Birgitte

    Formålet med rapporten er at præsentere en metode og en brugsanvisning, der kan anvendes til registrering og kortlægning af økonomiske omkostninger/effekter ved arbejdsulykker (ulykkesomkostninger) samt en guideline til brug ved konkretisering af de mere uhåndgribelige afledte effekter, som disse...

  11. Organisering af projektudvikling - KulturarvNord

    DEFF Research Database (Denmark)

    Mark, Stine

    Organisering af projektudvikling - KulturarvNord er udarbejdet af forskningscenteret INCEVIDA, Aalborg Universitet 2012, og gennemført i et samarbejde mellem INCEVIDA og museumsnetværket KulturarvNord. I rapporten tages der udgangspunkt i empirisk materiale indhentet via interviews med nøgleperso...

  12. Tre generationer af Flow Injection Analysis

    DEFF Research Database (Denmark)

    Hansen, Elo Harald; Chomchoei, Roongrat; Long, Xiangbao

    2004-01-01

    Siden introduktionen af FIA har en række videreudviklinger resulteret i Sequential Injection Analysis (SIA) og senest i Lab-on-Valve (LOV)-metodikken. Her beskrives disse, og der gives eksempler på, hvordan metoderne kan bruges til at bestemme sporstofkoncentrationer af metaller i komplekse...

  13. Digitale leverancer ved aflevering af byggeri

    DEFF Research Database (Denmark)

    Bertelsen, Niels Haldor; Sørensen, Nils Lykke; Shaukat, Fatima

    Udviklingen af det digitale byggeri i Danmark har haft meget fokus på klassifikation, fælles standarder og digitale værktøjer, som skal understøtte en centralt styret bygningsmodel. Der er ved at ske et paradigmeskift, hvor den praktiske anvendelse af IKT i de enkelte faggrupper er mere i centrum...

  14. Cyberwarfares udfordringer af begrebet kritisk infrastruktur

    DEFF Research Database (Denmark)

    Lauta, Kristian Cedervall; Hoffmann, Rune; Struwe, Lars Bangert

    I dag er der en stigende bekymring for cyberwarfare eller cyberkriminalitet. Det skyldes, at det moderne samfund er komplekst og sårbart. Samfundet baserer sig på udbuddet af stadig flere funktioner, som bliver tiltagende avancerede og internt afhængige af hinanden. Systemet bliver herved så avan...

  15. Kritikken af new public management er forfejlet

    DEFF Research Database (Denmark)

    Klausen, Kurt Klaudi

    2016-01-01

    kronikken adresserer og korrigerer den opfattelse at de nyliberalistiske reformer under betegnelsen NPM ikke har bidraget positivt til moderniseringen af den offentlige sektor.......kronikken adresserer og korrigerer den opfattelse at de nyliberalistiske reformer under betegnelsen NPM ikke har bidraget positivt til moderniseringen af den offentlige sektor....

  16. Manual reduktion af pattegrisedødelighed

    DEFF Research Database (Denmark)

    Bonde, Marianne; Serup, Tove

    svært at opretholde en målrettet indsats. Aarhus Universitet, Det Jordbrugsvidenskabelige Fakultet, Foulum har siden 2007 arbejdet på forskningsprojektet Reduceret pattegrisedødelighed og fravænningsdiarre. Et af produkterne fra dette projekt er denne manual for reduktion af pattegrisedødelighed...

  17. Gyldigheden af antagelsen om Gaussisk Turbulens

    DEFF Research Database (Denmark)

    Nielsen, Morten; Hansen, Kurt S.; Pedersen, Bo Juul

    2000-01-01

    Vindmøller designes til at modstå virkningen af den turbulente vind, og i den forbindelse plejer men at antage at hastighedens sansynlighed er normalfordelt. Det synes, på baggrund af et stort antal målinger fra flere lokaliteter, at være en rimelig antagelse i fladt homogent terræn, men der find...

  18. Hvad forklarer forskellige typer af frivilligt engagement?

    DEFF Research Database (Denmark)

    Henriksen, Lars Skov; Rosdahl, David

    2008-01-01

    Artiklen undersøger empirisk gennem multivariate analyser betydningen af forskellige former for personlige og sociale ressourcer for tre forskellige typer af formelt frivilligt arbejde: aktivitetsorienteret frivilligt arbejde, velfærdsorienteret frivilligt arbejde samt politisk og (lokal)samfunds......)samfundsorienteret frivilligt engagement....

  19. Prioriteringer af efterretninger i kampen mod terror

    DEFF Research Database (Denmark)

    Nielsen, Thomas Galasz

    2015-01-01

    Efterretningstjenesterne indsamler stadig flere informationer i forsøget på at opdage og imødegå terrorister. Men mængden af informationer gør det ikke nødvendigvis lettere at forudsige terrorhandlinger. Efterretningstjenesterne bør derfor prioritere bearbejdning af oplysningerne højere, end de gør...

  20. Udvikling af intelligent legepraksis i trampoliner

    DEFF Research Database (Denmark)

    Elbæk, Lars; Karoff, Helle Skovbjerg; Rytz Alison, Sigrid

    2012-01-01

    digitale aktiviteter. Det sikkerhedsmæssige er afgørende at medtænke, når der designes et digitalt add-on til en trampolin. Hvordan kan det fremmes uden at legen hurtigt bliver kedelig? Dette var en af de store udfordringer i udviklingen af den intelligente trampolin, som der redegøres for i artiklen...

  1. Udvikling af pille-doserings teknologi

    DEFF Research Database (Denmark)

    Brændgaard, Rikke; Churchill, Inge-Lise; Bolvig Poulsen, Søren;

    2015-01-01

    Lab. X har i samarbejde med Brønderslev Kommune og Firmaet LT Automation i et idegenereringsforløb omhandlende viden om "pillens vej", indhentet viden om udfordringer og barrierer i forbindelse med udlevering af medicin fra apoteket til den afslutningsvis indtages af borgeren. Formålet med unders...

  2. Grundtvigs nationalisme i lyset af nationalismeteori

    DEFF Research Database (Denmark)

    Böss/Bøss, Michael

    2013-01-01

    af det modernistiske paradigme har gjort det muligt at diskutere Grundvigs syn på fædreland og folk på en mere nuanceret måde end tidligere. Artiklen argumenterer for, at Grundtvigs tanker om folket skal forstås som en fornyelse og demokratisering af 1700-tallets patriotisme og en geopolitisk...

  3. Dimensionering af fortrængningsventilation

    DEFF Research Database (Denmark)

    Nielsen, Peter Vilhelm

    2000-01-01

    Lufthastigheden og temperaturfordelingen er væsentlige elementer i bestemmelsen af den termiske komfort i rum med fortrængningsventilation. Det er derfor vigtigt at fastlægge disse størrelser i selve designproceduren. Aalborg Universitet har udviklet en forenklet metode til bestemmelse af lufthas...

  4. Deregulering af arbejdsretlige EU-direktiver

    DEFF Research Database (Denmark)

    Hasselbalch, Ole; Rønnow Bruun, Jørgen

    2013-01-01

    Europa-Kommissionen vil lette de ”reguleringsmæssige byrder” for små og mellemstore virksomheder (SMV). Langt hovedparten af de danske virksomheder er SMV´er. Konsekvenserne af initiativet kan derfor blive særdeles vidtgående på dansk grund. Artiklen drøfter, om det overhovedet er muligt i henhold...

  5. Forført af hjernen?

    DEFF Research Database (Denmark)

    Lieberoth, Andreas

    2013-01-01

    Blandingen af offentlig interesse, gode mediehistorier og smarte sælgere har ført til sejlivede neuromyter, der ikke bare distraherer almindelige mennesker, men også fører til udbredte misforståelser blandt professionelle som lærere og plejepersonale. I bedste fald leder neuromyter til spild af t...

  6. Måling af virksomheders administrative byrder

    DEFF Research Database (Denmark)

    Langsted, Lars Bo

    2004-01-01

    Selskabsstyrelsen har offentliggjort rapporten: "Rapport om måling af virksomhedernes administrative byrder ved årsregnskabsloven og rapport om revisionshonorar for B-virksomheder."......Selskabsstyrelsen har offentliggjort rapporten: "Rapport om måling af virksomhedernes administrative byrder ved årsregnskabsloven og rapport om revisionshonorar for B-virksomheder."...

  7. Effets d’une compression cochléaire et d’une sélectivité en fréquence réduites sur la discrimination de la hauteur de tons complexes

    DEFF Research Database (Denmark)

    Santurette, Sébastien; Bianchi, Federica; Fereczkowski, Michal

    2016-01-01

    mécanismes de codage de l’enveloppe, cette étude examine si des changements dans le traitement de l’enveloppe chez des sujets avec PANS ont des conséquences sur la discrimination de la hauteur. Des seuils de discrimination de fréquence fondamentale (SDF0) sont tout d’abord obtenus chez 14 sujets à audition...... normale et 10 sujets avec PANS pour des tons complexes dont les harmoniques sont ajoutées soit en phase sinusoïdale (PS) soit en phase aléatoire (PA). Pour des harmoniques non résolues, une PANS entraîne des SDF0 plus élevés que chez les personnes à audition normale dans la condition PA, mais similaires...... dans la condition PS. La compression cochléaire et la bande passante des filtres auditifs sont ensuite estimés chez les mêmes sujets. Les résultats démontrent une corrélation significative entre la réduction de la compression cochléaire et le rapport entre les SDF0 pour les conditions PA et PS. Les...

  8. Miljøvurdering af isoleringsmetoder

    DEFF Research Database (Denmark)

    Krogh, H.; Rasmussen, J.O.; Nielsen, P.A.

    Når man skal gennemføre miljørigtigt byggeri er det nødvendigt at have adgang til miljødata for materialerne der knytter sig til produktet gennem hele dets livsforløb. I denne rapport præsenteres kvantitative miljødata for fremstilling af isoleringsprodukter. Det drejer sig om løsfyldsproduklter ...... cellulosefibre, ruller og plader af hør samt produkter af perlite. Rapporten viser også, hvordan disse data kan benyttes til at beregne miljøbelastninger for hele bygningsdele. Desuden gives en kvantitativ vurdering af produkternes miljøpåvirkninger af indeklimaet og ved bortskaffelse...

  9. Om fortolkning af Bernerkonventionen. Er Bernerkonventionen et maksimalistisk instrument?

    DEFF Research Database (Denmark)

    Blomqvist, Jørgen

    2016-01-01

    Bernerkonventionens formålsbestemmelser analyseres i lyset af deres betydning for fortolkning af konventionen. Det konstateres, at konventionen ikke tilstræber det absolut maksimale niveau af beskyttelse....

  10. Optimering af behandlingseffekten i akvakultur. Minimering af forbrug og udledning af hjælpestoffer

    DEFF Research Database (Denmark)

    Sortkjær, Ole; Henriksen, Niels Henrik; Demuth Heinecke, Rasmus;

    er 1/5 af, hvad der normalt anvendes. Brintoverilte omsættes hurtigt, så det er nødvendigt at supplere med brintoverilte under behandlingen i damme. Forsøg med biofilter viser, at formalin omsættes hurtigere, hvis det i forvejen har været eksponeret med formalin, og det skader ikke den mikrobielle...... behandlingstiden samtidig bliver forlænget, sådan som toksicitetstestene viser. For at bekæmpe fiskedræberen skal der behandles flere gange med nogle dages mellemrum, når dambruget er hårdt inficeret. I recirkulerende anlæg med biofilter er det nødvendigt at supplere med formalin for at holde koncentrationen under...

  11. DVD anmeldelse - En Verden af Lyd og Musik

    DEFF Research Database (Denmark)

    Holck, Ulla

    2006-01-01

    Anmeldelse af DVD-udgivelse af Claus Bang (2005): En Verden af Lyd og Musik. Musikterapi for døve, hørehæmmede og multihandicappede børn og unge. Al tale med undertekst eller tegnsprogstolkning. DVD-boks med 3 stk. dobbeltlag DVD beregnet til afspilning på PC. Udgivet af Musikterapi-foreningen En...... Verden af Lyd og Musik; produceret af Zenaria, Aalborg. Se også www.clausbang.com...

  12. 供气式呼吸防护装备用压缩空气质量标准建议%Advices on the setup of standard about compressed air quality of atmosphere-supplying respiratory protective devices

    Institute of Scientific and Technical Information of China (English)

    张明明

    2011-01-01

    该文简要介绍了供气式呼吸防护装备中提供给佩戴人员呼吸朋的压缩空气中潜存的污染物的种类、污染来源及其危害性,以及当前我国供气式呼吸防护装备用压缩空气的主要质最控制过程及管理措施,从健全标准体系和完善管理角度考虑,指出建立我国供气式呼吸防护装备用压缩窄气质量技术管理标准的迫切需要.在分析借鉴欧盟、美国等的呼吸防护装备用窄气的质量管理标准及管理方式的基础上,结合我国相关领域空气质最技术标准的已有经验,对我国未来供气式呼吸防护装备用压缩空气质量的技术管理标准的技术内容、具体控制指标及实施方式等多方面提出了建议.%In order to make up for a deficiency in the Chinese respiratory protection standard system and workplace safety management, the standard about the quality of compressed air used by air-supplying respiratory protective device is necessary to be prepared.In paper, compressed air was briefly introduced about pollutions, potential hazards, quality controlling methods, and the equivalent standards applied in Europe and USA.Then, some advice on controlling items, test methods, and implementation was given on the new coming standard.

  13. Trykfald over en bed af fliskoks

    DEFF Research Database (Denmark)

    Hindsgaul, Claus; Henriksen, Ulrik Birk

    En (atmosfærisk) luftstrøm ledtes gennem en fast bed af delvist forgasset fliskoks med en binær partikelstørrelsesfordeling (8 og 16 mm). Under variation af størrelsesfordeling og strømningshastighed registreredes det resulterende trykfald gennem bedden. Eksisterende estimationsformler for trykfa......En (atmosfærisk) luftstrøm ledtes gennem en fast bed af delvist forgasset fliskoks med en binær partikelstørrelsesfordeling (8 og 16 mm). Under variation af størrelsesfordeling og strømningshastighed registreredes det resulterende trykfald gennem bedden. Eksisterende estimationsformler...... for trykfaldet blev valideret for de givne kokspartikler. Note: Dette er en bearbejdning af rapporten “Trykfald over en Bed af Fliskoks” ved Donovan og Hindsgaul 1997 [1]. I nogle tilfælde er brugen af symboler ændret i forhold til rapporten for at opnå bedre konsistens ligesom fundne fejl er rettet. Både den...

  14. Performance of Non-Supplementary Fired Compressed Air Energy Storage with Molten Salt Heat Storage%采用熔融盐蓄热的非补燃压缩空气储能发电系统性能

    Institute of Scientific and Technical Information of China (English)

    薛小代; 陈晓弢; 梅生伟; 陈来军; 林其友

    2016-01-01

    提出一种采用熔融盐蓄热的非补燃压缩空气储能发电系统,通过将熔融盐储热与压缩空气储能相结合,实现电能的大规模存储和高效转换。利用熔融盐作为蓄热介质,将低谷电、弃风电、弃光电等电能转换为高品位热能存储,同时利用压缩机将空气压缩至高压,存储在储气装置中,发电时利用熔融盐储存的热能加热高压空气驱动涡轮机发电。完成了系统的流程设计,采用热力学基本原理分析了系统的运行特性,探索影响系统储能效率的关键因素,分析了涡轮机进口温度、涡轮机进口压力等参数对压缩机功耗、储气室容积、储能密度、储能效率等系统性能的影响。研究结果表明通过提高储热温度和涡轮机进口压力,可以显著提高系统的储能效率。该系统可以广泛消纳大规模的波动性电能,为大规模储能提供了一种新的技术途径。该研究结果可以为压缩空气储能以及新能源消纳提供参考。%A non-supplementary fired compressed air energy storage (CAES) with molten salt thermal storage is proposed in this paper. Combined molten salt with compressed air energy storage, this system can achieve mass storage and efficient conversion of electrical energy. The off-peak power or abandoned wind and photoelectric power is converted into high-grade thermal energy, which is stored in the molten salt heat storage system. Meanwhile the air is compressed to high pressure and then stored in the gas storage device. The high pressure air heated by the molten salt can drive turbine to generate electricity when it is needed. The process design is completed with basic principle of thermodynamic analysis, and the key factors that affect the system efficiency are explored. The results show that the storage efficiency can be significantly improved by increasing the thermal storage temperature and turbine inlet pressure, which could provide a

  15. Vurdering af omfang og konsekvenser af sprøjtning og gødskning af § 3-beskyttede naturarealer

    DEFF Research Database (Denmark)

    Strandberg, Morten Tune; Bak, Jesper Leth; Bladt, Jesper Stentoft;

    2012-01-01

    Det er overvejende de ferske enge, der gødskes og sprøjtes, hvorimod dette kun undtagelsesvist er konstateret på andre naturtyper som overdrev og heder m.m. De ferske enge er samtidig den mest udbredte § 3-naturtype. Behandling i form af gødskning og sprøjtning foregår anslået på op til 20 % af a...

  16. Vurdering af hygiejniseringseffekten af nedsivning af viral hæmorrhagisk septikæmi virus (VHSV) under eksperimentelle forhold

    DEFF Research Database (Denmark)

    Skall, Helle Frank; Olesen, Niels Jørgen; Jørgensen, Claus

    2011-01-01

    P.t. er nedsivning den i Danmark eneste godkendte metode til hygiejnisering af spildevand fra fiskeopskærings-virksomheder. For at belyse effekten af denne proces er der i dette projekt foretaget eksperimentel undersøgelse af nedsivning af viral hærmorrhagisk septikæmi virus (VHSV) i en søjle...... pakket med grus som top- og bundlag (i alt 22 cm) og bakkesand (76 cm). Over en periode på 18 timer blev der påført 3,9 x 1010 TCID50 (cellekultur infektive doser) VHSV til søjlen hvorefter der blev påført postevand i resten af forsøgstiden. Forsøget kørte over 7 dage, og i den tid blev der udtaget...... prøver fra udløbet til virologisk undersøgelse. Prøveudtagningen var mest intensiv i den periode hvor der var størst risiko for at VHSV kom ud af i bunden søjlen. Der blev ikke påvist virus ved den virologiske undersøgelse. Da den virologiske undersøgelses følsomhed var 13,9 TCID50/ml kunne der påvises...

  17. Blended Learning Analytics Model for Evaluation (BLAME. Et case-studie af universitetsunderviseres brug af Blackboard

    Directory of Open Access Journals (Sweden)

    Peter Musaeus

    2015-10-01

    Full Text Available I denne artikel vil vi præsentere en strategi til inddragelse af læringsanalytik (learning analytics ved evaluering af universitetsunderviseres brug af et nyt LMS på Aarhus Universitet: Blackboard. Vi diskuterer en model (BLAME: Blended Learning Analytics Model of Evaluation for, hvordan kategorisering af kurser og data om læringsanalytik indsamlet på Blackboard kan integreres. Endvidere belyser vi, hvilke implikationer en sådan læringsanalytik kan have for blended learning ved at analysere to forskellige uddannelses-cases/illustrationer. Dernæst diskuterer vi pædagogisk udvikling i forbindelse med evalueringsrapport om underviseres brug af Blackboard som beslutningsstøtte for feedback og pædagogisk intervention. Artiklen slutter med en diskussion af, hvordan data til læringsanalytik bør indsamles i LMS og bruges til afrapportering og undervisningsudvikling.

  18. Optimering af byggeprocessen via bedre/forøget brug af digitale modeller

    DEFF Research Database (Denmark)

    Carlsen, Mads; Grøn, Dorte Marie Frilund; Alon, Nevo;

    2013-01-01

    Projektet klarlægger nødvendigheden for, og muligheder i, en struktureret og konsekvent planlægning ved anvendelsen af BIM i relation til projektering, udførelse og drift af byggeri. Der er udarbejdet et planlægningsværktøj, der muliggør en sådan planlægning. Samtidig kortlægges de nødvendige data......, der kan udtrækkes af en BIM model ved gennemførelsen af en LCA simulering. Projektet afsluttes med en præsentation af en udviklet demonstratorapplikation til gennemførelse af LCA simuleringer koblet med BIM modellen....

  19. OLM dispersion calculations based on 10 years' meteorology in relation to the Danish Air Quality Guideline; OML-spredningsberegninger paa basis af 10 aars meteorologi i relation til Luftvejledningen

    Energy Technology Data Exchange (ETDEWEB)

    Loefstroem, P.; Roerdam Olesen, H.

    2008-12-15

    In the Danish Air Quality Guideline (Luftvejledningen) the Danish Environmental Protection Agency recommends that the OML atmospheric dispersion model is used for compliance checking for industrial facilities. The current procedure to compare concentration levels with the limit value is based on the use of one years' worth of meteorological data. In order to obtain a better statistically founded basis for assessing the level of air pollution, the present study examines how the current use of one year of meteorological data can be extended to 10 years. The current use of only one year of data occasionally causes problems in the interpretation of the geographical distributions of the concentration levels. That is because different levels in different directions from the source might be due to random meteorological conditions, or due to the source configuration. The procedure is based on the statistical parameter known as the maximum monthly 99-percentile for one meteorological year (Kastrup Airport 1976). The present study uses 10 years of meteorological data from two Danish airports in Kastrup and AAlborg. These data are used for dispersion calculations for different types of point sources with varying stack heights, plume rise and possible nearby buildings. In order to obtain a new statistical parameter for the exposure - that corresponds to the current level of the maximum monthly 99-percentile and can be compared to the C-value ('limit value') of the Guideline the new statistics are based on the 120 monthly 99-percentiles for the 10 years of calculations. The 99-percentiles are ranked, and selected statistics are assessed, e.g. the maximum of all monthly 99-percentiles, the 4th highest monthly 99-percentile, the 8th highest monthly 99-percentile, the 12th highest monthly 99-percentile, and the average monthly 99-percentile. The study recommends that in future assessments the statistical parameter to be compared with the C-value of the Guideline is

  20. Arbejdsmiljø ved udbud af busdrift

    DEFF Research Database (Denmark)

    Wiegmann, Inger-Marie; Mathiesen, Karin; Hasle, Peter

    En undersøgelse af sammenhængen mellem arbejdsmiljø og udbud af busdrift i tre trafikselskabet. Resultaterne peger på at arbejdsmiljøet går fra udelukkende til at være et anliggende mellem arbejdsgiver og arbejdstager til et trepartsforhold hvor også udbyder (trafikselskabet) får et ansvar og har...

  1. Danskernes brug af business case og gevinstrealisering

    DEFF Research Database (Denmark)

    Ernst, Martin

    2013-01-01

    Business case og gevinstrealisering har længe været faste begreber, når man taler effektivisering, implementering af strategi etc. Mange bruger det, flere brugere det delvist, og nogle bruger det slet ikke.......Business case og gevinstrealisering har længe været faste begreber, når man taler effektivisering, implementering af strategi etc. Mange bruger det, flere brugere det delvist, og nogle bruger det slet ikke....

  2. Please change your AFS/Linux Passwords

    CERN Multimedia

    2003-01-01

    Following some serious computer break-ins, which have exposed a number of passwords, users of AFS and Linux systems, including LXPLUS, are requested to change passwords as soon as possible. This especially concerns passwords typed at CERN, as well as any typed at remote sites while connected through CERN, since 18 March 2003. Use 'kpasswd' to change your AFS passwords. Further password advice is at: http://cern.ch/security/passwords Denise Heagerty, CERN Computer Security Officer, Computer.Security@cern.ch

  3. Blended Learning Analytics Model for Evaluation (BLAME). Et case-studie af universitetsunderviseres brug af Blackboard

    DEFF Research Database (Denmark)

    Musaeus, Peter; Bennedsen, Andreas Brændstrup; Hansen, Janne Saltoft;

    2015-01-01

    I denne artikel vil vi præsentere en strategi til inddragelse af læringsanalytik (learning analytics) ved evaluering af universitetsunderviseres brug af et nyt LMS på Aarhus Universitet: Blackboard. Vi diskuterer en model (BLAME: Blended Learning Analytics Model of Evaluation) for, hvordan...... kategorisering af kurser og data om læringsanalytik indsamlet på Blackboard kan integreres. Endvidere belyser vi, hvilke implikationer en sådan læringsanalytik kan have for blended learning ved at analysere to forskellige uddannelses-cases/illustrationer. Dernæst diskuterer vi pædagogisk udvikling i forbindelse...

  4. Første generation af miljøvurdering af kommune- og lokalplaner

    DEFF Research Database (Denmark)

    Larsen, A.; Lyhne, I.; Kristensen, J.N.;

    2006-01-01

    Artiklen præsenterer den første statusopgørelse på kommunernes arbejde med Lov om miljøvurdering af planer og programmer (SMV) og er den første empiriske undersøgelse af, hvad loven betyder for kommunernes planlægning.......Artiklen præsenterer den første statusopgørelse på kommunernes arbejde med Lov om miljøvurdering af planer og programmer (SMV) og er den første empiriske undersøgelse af, hvad loven betyder for kommunernes planlægning....

  5. Enzymatisk omestring til produktion af biodiesel

    DEFF Research Database (Denmark)

    Fjerbæk, Lene

    2007-01-01

      Biodiesel er i dag sammen med bioethanol et bud på, hvordan transportsektoren kan nedbringe sin netto CO2-emission til atmosfæren og lagrene af fossilt brændstof kan strækkes. På verdensplan forventes der en produktion af biodiesel på 7,9 mio. tons i 2007. Ved den industrielle fremstilling af...... biodiesel benyttes i dag kemiske katalysatorer såsom H2SO4, NaOH, MeONa eller KOH, der efterfølgende fjernes fra den producerede biodiesel med store mængder vand og derved produceres store mængder spildevand. Ved at benytte enzymer i processen kan man reducere mængden af spildevand, der skal renses. Enzymer...... benyttes ikke i de eksisterende processer, men det forventes, at udviklingen af processerne vil øge deres anvendelse i biodieselproduktion. I artiklen præsenteres fordele og ulemper ved anvendelse af enzymer til biodiesel produktion....

  6. Pædagogisk brug af test

    DEFF Research Database (Denmark)

    Nordenbo, Sven Erik; Allerup, Peter; Andersen, Hanne Leth

    Publikationen er resultatet af et systematisk review foretaget i regi af Dansk Clearinghouse for Uddannelsesforskning. Reviewets grundspørgsmål er: Hvordan kan grundskolelæreres individ- og klassecentrerede brug af data fra test forbedre læreres didaktiske og/eller fagdidaktiske tiltag i klasser...... med almindelige elever? Spørgsmålet vedrører alene testtyper, som indgår i nationale test i de nordiske lande. Og hvordan indvirker indførelsen af testning på læreres didaktiske beslutninger og elevers læringsadfærd? Vi fandt frem til at grundskolelæreres individ- og klassecentrerede brug af testdata...... i klasser med almindelige elever forbedres, når de didaktiske og/eller fagdidaktiske tiltag bygger på test, som lærerne oplever et medejerskab for. Vi fandt fremtil, at introduktion af test fra instanser over klasseniveau med det formål at indvirke på undervisning og elevers læringsadfærd har...

  7. Læring som improviseret udvikling af praksis

    DEFF Research Database (Denmark)

    Brinck, Lars

    2010-01-01

    Med afsæt i forfatterens fænomenografiske studie af amerikanske musikeres oplevelse af det at jamme diskuterer artiklen, hvorvidt jam-bandets spontant improviserende praksis kan give ny forståelse af rytmiske musikeres læring som et overordnet socialt fænomen. Ved at betragte jam-bandets praksis i...

  8. Udvikling af informationskompetence i problemorienterede læreprocesser

    DEFF Research Database (Denmark)

    Andreasen, Lars Birch; Jørgensen, Lars; Lerche Nielsen, Jørgen

    2007-01-01

    begreberne om problemorienteret projektarbejde og informationskompetence i forhold til forståelsen af læring og af sammenhængen mellem information og viden. Og artiklen peger på betydningen af relationer og oplevelsen af relevans for at skabe sammenhæng mellem bibliotekers og uddannelsers praksis. Artiklen...

  9. Om den sociale og symbolske funktion af uddannelsesevalueringer

    DEFF Research Database (Denmark)

    Nørholm, Morten

    Ph.d.-afhandlingen handler om evalueringer, om evalueringer af uddannelse med et fokus og perspektiv som er begrænset til en afdækning af forhold om evalueringer, til en formulering af en teori om evalueringer. I afhandlingens analyser og diskussioner anvendes teorier af Émile Durkheim, Pierre...

  10. Poetisk verbalbrug og sproglig datering af gammeltestamentlige tekster

    DEFF Research Database (Denmark)

    Siegismund, Kasper

    2013-01-01

    Denne artikel giver en kort introduktion til diskussionen af sproglig datering af tekster fra det Gamle Testamente og en vurdering af det alternative, ikke-kronologiske synspunkt, der er blevet fremført af Young, Rezetko og Ehrensvärd. To poetiske tekster, der almindeligvis betragtes som arkaiske...

  11. Kommentarer til love og ændringer af love

    DEFF Research Database (Denmark)

    Møgelvang-Hansen, Peter

    2002-01-01

    folkeoplysende foreningsarbejde og Folkeuniversitetet (folkeoplysningsloven) og ophævelse af lov om daghøjskoler m.v. og lov om den fri ungdomduddannelse samt ændring af lov om refusion af udgifter til uddannelse i forbindelse med aktivering m.m. samt ændring af forskellige love (Reform for daghøjskolerne...

  12. Kontrol af konventionelle våben i Europa

    DEFF Research Database (Denmark)

    Hoffmann, Rune; Kierulf, John; Pradhan-Blach, Flemming

    Rapporten indledes med en historisk gennemgang af tilblivelsen og udviklingen af Traktat om Konventionelle Væbnede Styrker i Europa (CFE), som blev iværksat af NATO og det tidligere Warszawapagten i 1973. Traktaten fastsætter et loft for antallet af kampvogne, pansrede kampkøretøjer, artilleripje...

  13. Ramme- og lokalaftaler om organisering af virksomheders sikkerheds- og sundhedsarbejde

    DEFF Research Database (Denmark)

    Sørensen, Ole Henning; Hasle, Peter

    En undersøgelse af ramme aftaler mellem arbejdsmarkedets parter om alternative organisering af sikkerhedsorganisationen, samt en række virksomheders lokale aftaler om samme emne.......En undersøgelse af ramme aftaler mellem arbejdsmarkedets parter om alternative organisering af sikkerhedsorganisationen, samt en række virksomheders lokale aftaler om samme emne....

  14. Ekstraktion af aromastoffer fra tørret oregano

    DEFF Research Database (Denmark)

    Christensen, Knud; Jakobsen, Jens Ellitsgård; Christensen, Jens Porskjær

    2007-01-01

    Ligevægtsforhold omkring ekstraktion af aktivstoffer fra oregano vulgaris med ethanol og vand er undersøgt med henblik på industriel fremstilling af tinkturer er undersøgt. Væskeoptag i tørret oregano som funktion af væskesammensætning er bestemt. Sammensætningen af aktivstoffer i ekstraktet som...

  15. P-Fuzzy Sets(AF,AF)and its Applications%P-模糊集(AF,AF)及其应用

    Institute of Scientific and Technical Information of China (English)

    闫立梅; 徐凤生; 史开泉

    2011-01-01

    By introducing dynamic characteristics to finite ordinary set X, the ordinary set Xwas improved and P-sets (packet sets) was proposed. P-sets is a pair of sets composed of internal P-set XF (internal packet set XF) and outer P-set XF (outer packet set XF), or, (XF, XF) is P-sets. P-sets has dynamic characteristics, that is, internal P-set has internal dynamic characteristics and outer P-set has outer dynamic characteristics. P-sets (XF , XF) was introduced to fuzzy set A of L. A. Zadeh,the fuzzy set A of L. A. Zadeh was improved,P-fuzzy sets(packet fuzzy sets) was given. P-fuzzy sets is a pair of fuzzy sets composed of internal P-fuzzy set AF (internal packet fuzzy set AF )and outer P-fuzzy set AF (outer packet fuzzy set AF) ,or, (AF ,AF) is P-fuzzy sets. P-fuzzy sets has dynamic characteristics, some properties and applications of P-fuzzy sets were given. Under certain conditions, P-fuzzy sets (AF ,AF)can come back to the original of ordinary fuzzy set A of L. A. Zadeh. P-fuzzy sets has more extensive applications than fuzzy set of L. A. Zadeh. P-fuzzy sets is a new direction of fuzzy set theory and applied research.%把动态特性引入到有限普通集合X内,改进了普通集合X,提出了P-集合(packet sets);P-集合是由内P-集合XF(internal packet set XF)与外P-集合XF(outer packet set XF)构成的集合对;或者(XF,XF)是P-集合.P-集合具有动态特性:内P-集合具有内-动态特性,外P-集合具有外-动态特性.把P-集合(XF,XF)引入到L.A.Zadeh模糊集A中,改进L.A.Zadeh模糊集A,提出P-模糊集(packet fuzzy sets).P-模糊集是由内P-模糊集AF(internal packet fuzzy setAF)与外P-模糊集AP(outer packet fuzzy set AF)构成的模糊集合对,或者(AF,AF)是P-模糊集.P-模糊集具有动态特性,给出了P-模糊集的若干特征与应用.在一定条件下,P-模糊集(AF,AF)能够回到L.A.Zadeh模糊集A的"原点".P-模糊集比L.A.Zadeh模糊集具有更大的应用空间.P-模糊集是模糊集理论与应用中的一个新的研究方向.

  16. Implementering og anvendelse af nyere ledelsesteknologier i den kommunale sektor

    DEFF Research Database (Denmark)

    Nielsen, Steen; Nielsen, Christian

    2009-01-01

    New Public Management vedrører transformeringen af ledelse i den offentlige sektor, bl.a. ved introduktion af nye krav til de offentlige ledere, herunder at skulle stå til regnskab for ressourceforbrug, kvaliteten af de leverede ydelser, samt en fornuftig anvendelse af skatteborgernes penge. En...... central del af New Public Management bevægelsen er derfor introduktionen af nye økonomistyringsteknikker og ledelsesmodeller. Denne artikel fokuserer på kendskab, udbredelse, prioritering og nytten af sådanne tiltag i kommunalt regi, og sætter fokus på, hvorvidt økonomistyringsteknikker og...

  17. Numerical Analysis of Autoignition and Combustion of n-Butane and Air Mixture in Homogeneous-Charge Compression-Ignition Engine Using Elementary Reactions

    Science.gov (United States)

    Yamasaki, Yudai; Iida, Norimasa

    The present study focuses on clarifying the combustion mechanism of the homogeneous-charge compression-ignition (HCCI) engine in order to control ignition and combustion as well as to reduce HC and CO emissions and to maintain high combustion efficiency by calculating the chemical kinetics of elementary reactions. For the calculations, n-butane was selected as fuel since it is a fuel with the smallest carbon number in the alkane family that shows two-stage autoignition (heat release with low-temperature reaction (LTR) and with high-temperature reaction (HTR)) similarly to higher hydrocarbons such as gasoline. The CHEMKIN code was used for the calculations assuming zero dimensions in the combustion chamber and adiabatic change. The results reveal the heat release mechanism of the LTR and HTR, the control factor of ignition timing and combustion speed, and the condition need to reduce HC and CO emissions and to maintain high combustion efficiency.

  18. Global opvarmning neutraliserer effekten af parasitisme på strandsnegles konsumption af makroalger

    DEFF Research Database (Denmark)

    Larsen, Martin H.; Mouritsen, Kim Nørgaard

    strukturen af makroalgesamfund ved at reducere konsumptionsraten hos den herbivore strandsnegl Littorina littorea. Det er endvidere vist, at produktionen af trematode-larver (cercarier) i sneglens fordøjelseskanal og gonade kompleks øges kraftigt når vandtemperaturen stiger. Man kan derfor forvente...

  19. Merværdien af LEADER

    DEFF Research Database (Denmark)

    Thuesen, Annette Aagaard; Nielsen, Niels Christian

    Formålet med anvendelse af LEADER-metoden er at sikre, at der tildeles midler til lokale projekter på en sådan måde, at de baserer sig på lokale strategier, vurderinger og hvad der efterspørges lokalt. I Danmark er der 57 lokale aktionsgrupper (LAG’er), sammenslutninger med foreningsstruktur der...... analyse af hvordan og i hvilket omfang fem danske LAG’er arbejder efter LEADER-principperne. Anvendelse af LEADER-metoden forudsætter dog, at den lokale udvikling sker ud fra en vedtaget strategi og i et lokalt offentligt-privat partnerskab – i et samarbejde, der kan tænke på tværs af interesser og skabe...... netværk og nye samarbejdsrelationer. Der bliver imidlertid stadig stillet spørgsmål til metodens effektivitet i forhold til jobskabelse og økonomisk udvikling. Derfor efterspørges der fra flere sider indikatorer for hvorvidt og hvordan anvendelsen af LEADER bidrager eller giver ekstra værdi til programmer...

  20. Compressive Sensing Over Networks

    CERN Document Server

    Feizi, Soheil; Effros, Michelle

    2010-01-01

    In this paper, we demonstrate some applications of compressive sensing over networks. We make a connection between compressive sensing and traditional information theoretic techniques in source coding and channel coding. Our results provide an explicit trade-off between the rate and the decoding complexity. The key difference of compressive sensing and traditional information theoretic approaches is at their decoding side. Although optimal decoders to recover the original signal, compressed by source coding have high complexity, the compressive sensing decoder is a linear or convex optimization. First, we investigate applications of compressive sensing on distributed compression of correlated sources. Here, by using compressive sensing, we propose a compression scheme for a family of correlated sources with a modularized decoder, providing a trade-off between the compression rate and the decoding complexity. We call this scheme Sparse Distributed Compression. We use this compression scheme for a general multi...

  1. Compression limits in cascaded quadratic soliton compression

    DEFF Research Database (Denmark)

    Bache, Morten; Bang, Ole; Krolikowski, Wieslaw;

    2008-01-01

    Cascaded quadratic soliton compressors generate under optimal conditions few-cycle pulses. Using theory and numerical simulations in a nonlinear crystal suitable for high-energy pulse compression, we address the limits to the compression quality and efficiency.......Cascaded quadratic soliton compressors generate under optimal conditions few-cycle pulses. Using theory and numerical simulations in a nonlinear crystal suitable for high-energy pulse compression, we address the limits to the compression quality and efficiency....

  2. Satellite data compression

    CERN Document Server

    Huang, Bormin

    2011-01-01

    Satellite Data Compression covers recent progress in compression techniques for multispectral, hyperspectral and ultra spectral data. A survey of recent advances in the fields of satellite communications, remote sensing and geographical information systems is included. Satellite Data Compression, contributed by leaders in this field, is the first book available on satellite data compression. It covers onboard compression methodology and hardware developments in several space agencies. Case studies are presented on recent advances in satellite data compression techniques via various prediction-

  3. Produktudvikling af fødevarer med Quality Function Deployment

    DEFF Research Database (Denmark)

    Bech, Anne C.

    1998-01-01

    Produktudvikling af fødevarer stiller stadig større krav til virksomhedernes kompetencer. QFD filosofien kan bidrage til at skabe en fælles forståelse af grundlaget for udvikling af nye produkter. Udgangspunktet er en forståelse af forbrugernes behov i relation til virksomhedens muligheder...... konkurrentprodukter. Efterfølgende faser handler om at generere forskellige mulige løsninger, inden der træffes valg af løsningsalternativ. Anvendelse af QFD modellen for produktudvikling betyder, at forbrugernes behov er centrale i hele produktudviklingsforløbet, samt at det udviklede produkt sigter mod at opfylde...... væsentlige identificerede behov set fra forbrugernes synspunkt. At virksomheden ser implementering af QFD som en investering, medarbejdernes commitment og målrettet projekt, er væsentlig for en succesfuld implementering af QFD til produktudvikling. QFD tankegangen illustreres med et eksempel på udvikling af...

  4. Bestemmelse af spormetaller i organisk materiale

    DEFF Research Database (Denmark)

    Tjell, Jens Christian; Palfeldt, Kirsten

    Behovet for pålidelige analysemetoder til bestemmelse af spormetalindhold i organiske materialer, f.eks. planter, slam og dyrevæv er stigende på grund af den stigende erkendelse af disse stoffers betydning for organismers fysiologi, både hvor disse stoffer optræder i uønskede koncentrationer som...... der over de sidste år udviklet en analyseprocedure hvorefter det er muligt at analysere for metallerne Mn, Cu, Ni, Co, Cr, Zn, Cd og Pb i planter, dyrevæv, jord, slam og andre materialer med standardafvigelser på mellem 5 og 10%. Der gøres rede for denne metode....

  5. Medicinsk teknologivurdering af akupunktur til gravide

    DEFF Research Database (Denmark)

    Feenstra, Maria Monberg; Johansen, Marianne; Sørensen, Lisbeth Falborg;

    -, organisatorisk- og økonomisk perspektiv. Metode: Der blev udarbejdet en medicinsk teknologivurdering (MTV). En alsidig og systematisk litteraturgennemgang af akupunkturbehandling til gravide med emesis/hyperemesis gravidarum, bækkenrelaterede smerter eller depression/angst blev udført. Den udvalgte litteratur...... behandlingen udføres korrekt af TCM-uddannet sundhedspersonale. Undersøgelser har vist høj patienttilfredshed blandt gravide ved akupunkturbehandling. Økonomiske beregninger dokumenterer, at akupunktur er et billigt behandlingstilbud. Konsekvenser for praksis: Det anbefales, at tilbyde gravide med emesis/hyperemesis...... gravidarum akupunkturbehandling. Udvalgt sundhedspersonale skal uddannes til at give behandlingen, og der bør tilstræbes kontinuitet i behandlingsforløbet. Yderligere studier, der undersøger evidensen for behandling af bækkenrelaterede smerter og depression/angst med akupunktur, anbefales....

  6. Studie af den amerikanske doktrin for Counterinsurgency

    DEFF Research Database (Denmark)

    Møller, Nicolai Stahlfest

    2006-01-01

    strategisk partner, og den mulige indsættelse i missioner, hvor kontakt med, og måske bekæmpelse af, fjendtlige oprørsbevægelser vil forekomme. Maos teori og den nyere radikale islams teori ses som værende repræsentative for oprørsbevægelser ift. både amerikanske erfaringer og det forventede danske...... synes også at være udtalt i imødegåelsen af radikal islam, hvilket er en stor udfordring for både militære og civile myndigheder og organisationer. For at fungere som COIN enhed kræver det veluddannede enheder, da de udover de basale soldateropgaver også skal kunne støtte ifm. CIMIC opgaver, løsning af...

  7. Energimæssig helhedsvurdering af vinduer

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe; Kristiansen, Finn Harken

    , hvor der kan findes et optimum for g-værdien. Størrelsen afhænger af den aktuelle vinduesfordeling på de fire verdenshjørner. Installation af køleanlæg kan undgås ved at anvende solafskærmende ruder, men energimæssigt og komfortmæssigt er de to løsninger omtrent ligeværdige på grund af, at solindfaldet......, så de begyndende overtemperaturer imødegås fra start. U-værdien for ramme/karmkonstruktionen har i Danmark ikke fulgt med udviklingen på rudeområdet, mens der i Tyskland er udviklet isolerende ramme/karmkonstruktioner i forbindelse med det såkaldte ”Passiv Haus” koncept. Herhjemme er de fleste forsøg...

  8. Relationship between streaming potential and compressive stress in bovine intervertebral tissue.

    Science.gov (United States)

    Fujisaki, Kazuhiro; Tadano, Shigeru; Asano, Nozomu

    2011-09-02

    The intervertebral disc is formed by the nucleus pulposus (NP) and annulus fibrosus (AF), and intervertebral tissue contains a large amount of negatively charged proteoglycan. When this tissue becomes deformed, a streaming potential is induced by liquid flow with positive ions. The anisotropic property of the AF tissue is caused by the structural anisotropy of the solid phase and the liquid phase flowing into the tissue with the streaming potential. This study investigated the relationship between the streaming potential and applied stress in bovine intervertebral tissue while focusing on the anisotropy and loading location. Column-shaped specimens, 5.5 mm in diameter and 3 mm thick, were prepared from the tissue of the AF, NP and the annulus-nucleus transition region (AN). The loading direction of each specimen was oriented in the spinal axial direction, as well as in the circumferential and radial directions of the spine considering the anisotropic properties of the AF tissue. The streaming potential changed linearly with stress in all specimens. The linear coefficients k(e) of the relationship between stress and streaming potential depended on the extracted positions. These coefficients were not affected by the anisotropy of the AF tissue. In addition, these coefficients were lower in AF than in NP specimens. Except in the NP specimen, the k(e) values were higher under faster compression rate conditions. In cyclic compression loading the streaming potential changed linearly with compressive stress, regardless of differences in the tissue and load frequency.

  9. Undersøgelsen af brugernes evaluering af kontorpakker på Århus Sygehus og i Psykiatrien i Århus

    DEFF Research Database (Denmark)

    Hørlück, Jens

    En analyse af brugernes opfattelse af kvaliteten af tre office pakker: MS Office 2003 / 2007 og OpenOffice.  ......En analyse af brugernes opfattelse af kvaliteten af tre office pakker: MS Office 2003 / 2007 og OpenOffice.  ...

  10. Kvantitativ delevaluering af Stofrådgivningen

    DEFF Research Database (Denmark)

    Frederiksen, Kirsten Søndergaard; Ravn, Signe

    Opsummering for Stofrådgivningsrapport Stofrådgivningen bad i foråret 2012 Center for Rusmiddelforskning, Aarhus Universitet, om at gennemføre en evaluering af stedets behandlingstilbud ved hjælp af to delundersøgelser, en kvalitativ og en kvantitativ. Den kvalitative delundersøgelse omfattede...... problemer såsom markante koncentrationsproblemer, depressive tanker og egentlige psykiatriske diagnoser. Rapporten viser, at der sker positive udviklinger for de unges stofforbrug under et behandlingsforløb ved Stofrådgivningen. Desuden sker der særligt en positiv udvikling i forhold til de unges...

  11. Fair proces og ledelse af inkrementel innovation

    DEFF Research Database (Denmark)

    Vestergaard, Bo

    2011-01-01

    I kapitel 18, Fair proces og ledelse af inkrementel innovation – med et strategisk procesdesign, tager Bo Vestergaard afsæt i de organisatoriske udfordringer, der opstår, når mellemledere skal implementere oppefra dikterede besparelser, som potentielt kan virke demotiverende på medarbejderne....... Kapitlet beskriver, hvordan man inden for en bredt funderet systemisk rammesætning og med begrebet fair proces som fortløbende styreprincip kan skabe og opretholde konstruktiv medarbejderinvolvering i sådanne forandrings- og innovationsforløb. Lederens forløbsstyring sammenfattes i følgende tre praksisnære...

  12. Analyse af vindklima ved Navitas Park

    DEFF Research Database (Denmark)

    Rasmussen, Michael R.; Lauridsen, Thomas Bank

    Formålet med denne vindklimaanalyse er at afklare, hvorvidt opførelsen af Navitas Park på Århus Havn vil medføre uhensigtsmæssige eller farlige vindforhold for fodgængere i området omkring bygningen.......Formålet med denne vindklimaanalyse er at afklare, hvorvidt opførelsen af Navitas Park på Århus Havn vil medføre uhensigtsmæssige eller farlige vindforhold for fodgængere i området omkring bygningen....

  13. Verifikation af optiske koordinatmålemaskiner

    DEFF Research Database (Denmark)

    Larsen, Erik

    Kalibrering af optiske måleudstyr kalibreres ofte på en måde der ikke er valgt hensigtsmæ ssig, set i forhold til de emner der efterfølgende måles på udstyret. Det er ofte ”de forhåndenvæ rende søms” metode der anvendes. Udviklingen af optiske måleudstyr går stæ rkt for tiden, og understøttes kra...

  14. Ingen gavnlige virkninger af tilskud med antioxidanter

    DEFF Research Database (Denmark)

    Skibsted, Leif Horsfelt; Jørgensen, Karina

    2006-01-01

    Ifølge Motions- og Ernæringsrådets nyeste rqapport er der ikke videnskabeligt belæg for at tilskud af antioxidanter reducerer risikoen for sygdomme. Samtidig frarådes danskerne at indtage store doser E-vitamin og beta-karoten.......Ifølge Motions- og Ernæringsrådets nyeste rqapport er der ikke videnskabeligt belæg for at tilskud af antioxidanter reducerer risikoen for sygdomme. Samtidig frarådes danskerne at indtage store doser E-vitamin og beta-karoten....

  15. Ingen gavnlige virkninger af tilskud med antioxidanter

    DEFF Research Database (Denmark)

    Skibsted, Leif Horsfelt; Jørgensen, Karina

    2006-01-01

    Ifølge motions- og ernæringsrådets nyeste rapport er der ikke videnskabeligt belæg for, at tilskud af antioxidanter reducrerer risikoen for sygdomme. Samtidig frarådes danskerne at indtage store mængder E-vitamin og beta-karoten.......Ifølge motions- og ernæringsrådets nyeste rapport er der ikke videnskabeligt belæg for, at tilskud af antioxidanter reducrerer risikoen for sygdomme. Samtidig frarådes danskerne at indtage store mængder E-vitamin og beta-karoten....

  16. Sygeliggørelsen af eksistensen

    DEFF Research Database (Denmark)

    Brinkmann, Svend

    2012-01-01

    I almen praksis præsenteres vi oftere end i andre specialer for problemer eller lidelser, der ikke umiddelbart synes at vedrøre sygdom, men er af mere eksistentiel karakter. Som de hjælpere vi er, vil vi forsøge at tage os af det, som patienten kommer med. Men vi skal passe på ikke at overbehandl...... og sygeliggøre livets almindelige tildragelser som f.eks. sorg, skyld, skam, uro og generthed. Læs denne artikel om det eksistentielle i konsultationen....

  17. Ajourføring af ISA 610

    DEFF Research Database (Denmark)

    Fabricius, Ole; Kiertzner, Lars

    2011-01-01

    Ajourføringen af ISA 610 indebærer generelle skærpelser i relation til den eksterne revisors risikovurderingshandlinger i forhold til intern revision samt til ekstern revisors revisionshandlinger på områder med væsentlig risiko og skønsmæssig usikkerhed.......Ajourføringen af ISA 610 indebærer generelle skærpelser i relation til den eksterne revisors risikovurderingshandlinger i forhold til intern revision samt til ekstern revisors revisionshandlinger på områder med væsentlig risiko og skønsmæssig usikkerhed....

  18. Forvaltning af et bykvarter i forandring

    DEFF Research Database (Denmark)

    Reddersen, J.

    En beskrivelse af et boligkvarter i Københavns Sydvest-kvarter - fra planlægningen i begyndelsen af 1900-tallet og selve bybygningen, som afsluttedes efter 2. verdenskrig, til den gradvise udtynding op gennem 60'erne og 70'erne, og frem til forsøg på nye planlægnings- og forvaltningsstrategier i ......'erne. Bogen vil kunne bruges som inspiration for såvel lægfolk som fagfolk, der bekymrer sig for bykvarterer og deres forandring....

  19. Lovbestemt delegation af forvaltningsvirksomhed til private

    DEFF Research Database (Denmark)

    Bønsing, Sten

    2013-01-01

    Forvaltningsretten regulerer forvaltningsmyndigheder, når disse udøver forvaltningsvirksomhed. I nogle tilfælde bestemmes det ved lov, at private skal udføre forvaltningsvirksomhed. Dette betyder imidlertid ikke, at forvaltningsretten samtidig automatisk følger med. Artiklen analyserer, hvordan...... forvaltningsvirksomhed udøves af private på grundlag af lov, og konstaterer, at forvaltningsretten kun i begrænset omfang sikrer borgernes retsstilling, når der træffes afgørelser mv. Retsstillingen kritiseres, og der angives forslag til, hvordan forvaltningsretten kan komme tilbage på banen, når private træffer...

  20. Leagile Manufacturing - implementering af modulariserede produktplatforme

    DEFF Research Database (Denmark)

    Bjarnø, Ole-Christian

    2003-01-01

    Lean og Agile (Leagile) Manufacturing indebærer ikke blot den rette balance (dekobling) mellem lean producerede komponenter og agile konfigurerede færdigvarer, og dermed til levering af individualiserede produkter til konkurrencedygtige priser og høj kvalitet, men også til effektivitet og...... fleksibilitet i produktudvikling og produktion. For at opnå integrationen mellem agile og lean kan der arbejdes med en vifte af integrationsmekanismer inden for organisatoriske og teknologiske virkemidler. Projektet har til formål at identificere, strukturere og modellere de centrale analyse- og...

  1. Epichlorhydrin og bisphenol A i mat-kontaktmaterialer af epoxylakeret metal og/eller af plast

    DEFF Research Database (Denmark)

    Petersen, Jens Højslev; Pedersen, Gitte Alsing; Foverskov, Annie;

    Det er ikke længere tilladt af bruge bisphenol A baseret polycarbonatplast til fremstilling af tåteflasker. Mattilsynet udtog i vinteren 2012/2013 7 typer af sutteflasker som blev kontrolleret for om de indeholdt polycarbonatbaserede plastdele. I alt 28 enkeltdele blev kontrolleret ved infrarød...... spektrometri. Herudover blev 6 tutekopper, bestående af 38 enkeltdele, analyseret med samme teknik. Der blev ikke påvist bisphenol A baseret plast ved analyserne. Dåser, bægre, tuber og skruelåg kan være lakeret på matkontaktsiden med epoxylakker fremstillet af monomererne epichlorhydrin og bisphenol A. Alle...... 50 enkeltdele fra disse prøver blev undersøgt ved infrarød spektrometri og 9 af prøverne viste tegn på at indeholde epoxylak. Disse prøver blev undersøgt ved en ”worst case” ekstraktionstest hvor der kunne påvises små indhold af bisphenol A i ekstrakterne mens der ikke kunne påvises epichlorhydrin...

  2. EPA Facility Registry Service (FRS): AIRS_AFS

    Data.gov (United States)

    U.S. Environmental Protection Agency — This web feature service contains location and facility identification information from EPA's Facility Registry Service (FRS) for the subset of facilities that link...

  3. EPA Facility Registry Service (FRS): AIRS_AFS_MAJOR

    Data.gov (United States)

    U.S. Environmental Protection Agency — This web feature service contains location and facility identification information from EPA's Facility Registry Service (FRS) for the subset of facilities that link...

  4. Simulering af ændret publikumsbelastning i Mols Bjerge

    DEFF Research Database (Denmark)

    Skov-Petersen, Hans; Foged, Mette

    2010-01-01

    Det kan være svært at forudse, hvad effekten af ændringer i adgangsforholdene til et naturområde vil blive. Dette Videnblad beskriver, hvordan en agent-baseret simuleringsmodel kan anvendes til vurdering af fremtiden ved flytning af en parkeringsplads ved trehøje i Mols Bjerge.......Det kan være svært at forudse, hvad effekten af ændringer i adgangsforholdene til et naturområde vil blive. Dette Videnblad beskriver, hvordan en agent-baseret simuleringsmodel kan anvendes til vurdering af fremtiden ved flytning af en parkeringsplads ved trehøje i Mols Bjerge....

  5. Compressive Strength of 2D-C/SiC Composite at High Temperature in Air%2D-C/SiC复合材料在空气中的高温压缩强度研究

    Institute of Scientific and Technical Information of China (English)

    牛学宝; 张程煜; 乔生儒; 韩栋; 李玫

    2011-01-01

    研究了二维碳纤维增强碳化硅基复合材料(2 D-C/SiC)在空气介质中的高温压缩强度.材料采用1K T300碳纤维平纹布经叠层和缝合制成预制体为增强体,经等温化学气相浸渗制备而成.试样表面用化学气相沉积工艺沉积SiC涂层.测试方向为垂直于炭布叠层方向,测试温度为室温,700℃,1100℃和1300℃.使用扫描电子显微镜观察了材料的断口.结果表明:室温~700℃,2D-C/SiC的压缩强度随温度升高逐渐增大,温度高于700℃后,材料的压缩强度缓慢降低.导致2D-C/SiC的压缩强度随温度变化的主要原因为纤维和基体热膨胀系数不同引起的残余应力随温度升高逐渐变小和高温下材料的氧化损伤.%The compressive strength of a two dimensional carbon fiber reinforced silicon carbide composite (2D-C/SiC) at elevated temperature in air was studied. The plain weaved carbon cloth was applied as reinforcement, made of stacked and seamed 1K T300 carbon fiber cloth. The 2D-C/SiC was prepared by isothermal chemical vapor infiltration. The specimens were coated with SiC by chemical vapor deposition. The tests were conducted at room temperature, 700°C , 1100°C and 1300°C respectively, and the loading direction was perpendicular to 2D-C/SiC plane. The fractured surface of the specimens was observed by a scanning electron microscope. The results show that the compressive strength increases gradually with increasing the temperature from room temperature to 700°C , while it decreases gradually when the temperature was above 700°C. The residual stress caused by the mismatch between the thermal expansion coefficients of the fiber and matrix, and the oxidation products play important roles in determining the compressive strength.

  6. Brugen af Geografiske Informationssystemer til effektundersøgelse af Intelligent Farttilpasning i Danmark

    DEFF Research Database (Denmark)

    Agerholm, Niels; Tradisauskas, Nerius; Bolet, Lars;

    2012-01-01

    Geografiske Informationssystemer er anvendt til at dels at dokumentere, hvilke effekter Intelligent Farttilpasning har på hastighedsoverskridelser, og dels til at undersøge, hvordan disse overskridelser kan præsenteres meningsfuldt i spatiale analyser. Analyser af effekten på kørselsadfærden er...... foretaget for ti af de deltagende bilister i et nordjysk Intelligent Fartilpasningsforsøg for unge bilister. Hovedresultaterne er, at Intelligent Farttilpasning nedbringer både størrelsen af hastighedsoverskridelser og længden på disse. Uden Intelligent Farttilpasning blev der især kørt for hurtigt på lange...

  7. Degradation of AF1Q by chaperone-mediated autophagy

    Energy Technology Data Exchange (ETDEWEB)

    Li, Peng; Ji, Min; Lu, Fei; Zhang, Jingru [Department of Hematology, Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital, Shandong University, Jinan 250012 (China); Li, Huanjie; Cui, Taixing; Li Wang, Xing [Research Center for Cell Therapy, Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital, Shandong University, Jinan 250012 (China); Tang, Dongqi, E-mail: tangdq@sdu.edu.cn [Research Center for Cell Therapy, Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital, Shandong University, Jinan 250012 (China); Center for Stem Cell and Regenerative Medicine, The Second Hospital of Shandong University, Jinan 250033 (China); Ji, Chunyan, E-mail: jichunyan@sdu.edu.cn [Department of Hematology, Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital, Shandong University, Jinan 250012 (China)

    2014-09-10

    AF1Q, a mixed lineage leukemia gene fusion partner, is identified as a poor prognostic biomarker for pediatric acute myeloid leukemia (AML), adult AML with normal cytogenetic and adult myelodysplastic syndrome. AF1Q is highly regulated during hematopoietic progenitor differentiation and development but its regulatory mechanism has not been defined clearly. In the present study, we used pharmacological and genetic approaches to influence chaperone-mediated autophagy (CMA) and explored the degradation mechanism of AF1Q. Pharmacological inhibitors of lysosomal degradation, such as chloroquine, increased AF1Q levels, whereas activators of CMA, including 6-aminonicotinamide and nutrient starvation, decreased AF1Q levels. AF1Q interacts with HSPA8 and LAMP-2A, which are core components of the CMA machinery. Knockdown of HSPA8 or LAMP-2A increased AF1Q protein levels, whereas overexpression showed the opposite effect. Using an amino acid deletion AF1Q mutation plasmid, we identified that AF1Q had a KFERQ-like motif which was recognized by HSPA8 for CMA-dependent proteolysis. In conclusion, we demonstrate for the first time that AF1Q can be degraded in lysosomes by CMA. - Highlights: • Chaperone-mediated autophagy (CMA) is involved in the degradation of AF1Q. • Macroautophagy does not contribute to the AF1Q degradation. • AF1Q has a KFERQ-like motif that is recognized by CMA core components.

  8. Analyse af RADS´vejledning vedrørende prostaglandiner til igangsættelse af fødsel

    DEFF Research Database (Denmark)

    Rydahl, Eva; Clausen, Jette Aaroe

    2014-01-01

    Analyse af RADS vejledning kritiserer det videnskabelige grundlag for anbefalinger af prostaglandiner til igangsættelse af fødsler. Der rejses spørgsmålstegn ved, om udvalget har været tro mod angivne metode, ved inddraget empiri og drager relevante konklusioner.......Analyse af RADS vejledning kritiserer det videnskabelige grundlag for anbefalinger af prostaglandiner til igangsættelse af fødsler. Der rejses spørgsmålstegn ved, om udvalget har været tro mod angivne metode, ved inddraget empiri og drager relevante konklusioner....

  9. Profeten Jeremias og genopbyggelsen af national identitet

    DEFF Research Database (Denmark)

    Holt, Else Kragelund

    2010-01-01

    Jeremias' Bog kan læses som et bidrag til kampen for at genopbygge den eksilsk-eftereksilske nation Israel. Baseret på social-antropologiske teorier om flygtninges livsvilkår, præsenteret af den amerikanske gammeltestamentler Daniel Smith-Christopher, beskrives Jeremias' Bog som en polyfone  teks...

  10. Brands som brikker i konstruktionen af identitet

    DEFF Research Database (Denmark)

    Hermansen, Judy

    2008-01-01

    Forbrug spiller en vigtig rolle i produktionen af mening og værdier, som kan skabe og vedligeholde både forbrugerens personlige og sociale verden - og derfor er reklame også en vigtig kilde til disse symbolske betydninger. Udgivelsesdato: juni...

  11. Coaching af ph.d.-studerende

    DEFF Research Database (Denmark)

    Godskesen, Mirjam Irene

    Rapporten danner grundlag for at etablere et koncept for ph.d.-coaching. Erfaringerne fra et 2-årigt projekt om ph.d.-coaching i SCKK regi beskrives. De centrale temaer er tilrettelæggelse af den individuelle coaching, typiske temaer i coachingen og arbejdsdeling mellem coach og vejleder. Der er...

  12. Udvikling af virksomhedens transformationssystem (produktions- og distributionssystemet)

    DEFF Research Database (Denmark)

    Pagh, Janus Dore

    Denne ph.d.-afhandling behandler emnet udvikling af den industrielle produktionsvirksomheds transformationssystem, der omfatter virksomhedens samlede produktions- og distributionssystem. Der er i de senere år komet stigende fokus på virksomhedernes evne til at skabe differentieret og kundetilpass...

  13. Evaluering af innovationskapacitet i erhvervsrettede uddannelser

    DEFF Research Database (Denmark)

    Haslam, Christian Ravn; Rosenstand, Claus Andreas Foss

    2015-01-01

    Danmarks økonomiske vækst skal bl.a. sikres gennem udvikling og anvendelse af innovationskapacitet. Landets uddannelser skal derfor sørge for, at studerende besidder de rette innovationskompetencer, hvorfor mange allerede har indført forskellige tiltag herfor. Det er dog stadig uklart, hvordan vi...

  14. Mest of compost, hangt af van doel

    NARCIS (Netherlands)

    Dekker, P.H.M.; Booij, R.

    2003-01-01

    Aanvoer van organische stof kan via verschillende bronnen: groenbemester, stro en gewasresten, dierlijke mest, zuiveringsslib, zwarte grond of compost. Welke bron gebruikt wordt hangt af van de bedrijfsspecifieke omstandigheden, en of er gestuurd wordt op aanvoer van effectieve organische stof, fosf

  15. Brandsikring af ventilationsanlæg

    DEFF Research Database (Denmark)

    Olufsen, P.

    Anvisningen er udarbejdet i tilknytning til Dansk Ingeniørforenings norm for brandtekniske foranstaltninger ved ventilationsanlæg, DS 428. Den er en vejledning i den praktiske anvendelse af normen skrevet for teknikere, der projekterer eller udfører ventilationsanlæg, eller som deltager i...

  16. LCA af Biovækst

    DEFF Research Database (Denmark)

    Møller, Jacob

    DTU ha færdiggjort en rapport, der beskriver en LCA (livscyklusvurdering) af kildesorteret organisk dagrenovation på BioVækst, et kombineret biogas- og komposteringsanlæg Rapporten beskriver en livscyklusbaseret miljøvurdering vha. LCA modellen EASEWASTE, for to behandlingsmetoder for kildesorteret...

  17. CT-skanninger af fossile hvaler

    DEFF Research Database (Denmark)

    Alstrup, Aage Kristian Olsen; Ramassamy, Benjamin Fernand Guy; Munk, Ole Lajord;

    2017-01-01

    CT-skannere er brugbare redskaber til undersøgelser af uddøde hvalarter. Dels kan skanningerne give indsigt i fossilernes indre anatomi, og dels kan de være nyttige, når konservatorerne efterfølgende skal præparere knoglerne frem. CT-skanningerne kan endvidere dokumentere knoglernes placering i...

  18. Nye tilgange til udpegning af risikolokaliteter

    DEFF Research Database (Denmark)

    Andersen, Camilla Sloth; Agerholm, Niels

    2012-01-01

    Den nuværende sortpletudpegning på det danske vejnet lider under faldende uheldsregistrering, og bliver derfor foretaget på et stadigt mere usikkert grundlag. Trafikforskningsgruppen på Aalborg Universitet arbejder i øjeblikket med to andre tilgange til udpegning af risikolokaliteter. Det ene er...

  19. På sporet af magtspillet om dansk naturfagsundervisning

    DEFF Research Database (Denmark)

    Schmidt, Jette Reuss

    Den neoliberale diskurs med tilhørende konkurrencemoment har længe været under beskydning i internationale forskningssammenhænge. Men der savnes konkrete eksempler på, hvordan neoliberal styring kommer til udtryk i nationale uddannelser. I denne afhandling følges derfor nogle af neoliberalismens...

  20. Ledelse af velfærd

    DEFF Research Database (Denmark)

    Lystbæk, Christian Tang

    2015-01-01

    (Osborne, 2006) og Public Value Management (Stoker, 2006). Endvidere er der blevet formuleret en række kodeks for offentlig ledelse, herhjemme blandt andet af Forum for offentlig topledelse (2005) og Væksthus for ledelse (2008). Endelig er der blevet fokuseret massivt på kompetenceudvikling for offentlige...