Roofbolters with compressed-air rotators

Science.gov (United States)

Lantsevich, MA; Repin Klishin, AA, VI; Kokoulin, DI

2018-03-01

The specifications of the most popular roofbolters of domestic and foreign manufacture currently in operation in coal mines are discussed. Compressed-air roofbolters SAP and SAP2 designed at the Institute of Mining are capable of drilling in hard rocks. The authors describe the compressed-air rotator of SAP2 roofbolter with alternate motion rotors. From the comparative analysis of characteristics of SAP and SAP 2 roofbolters, the combination of high-frequency axial and rotary impacts on a drilling tool in SAP2 ensure efficient drilling in rocks with the strength up to 160 MPa.

41 CFR 50-204.8 - Use of compressed air.

Science.gov (United States)

2010-07-01

... 41 Public Contracts and Property Management 1 2010-07-01 2010-07-01 true Use of compressed air. 50-204.8 Section 50-204.8 Public Contracts and Property Management Other Provisions Relating to Public... General Safety and Health Standards § 50-204.8 Use of compressed air. Compressed air shall not be used for...

Compressed air massage hastens healing of the diabetic foot.

Science.gov (United States)

Mars, M; Desai, Y; Gregory, M A

2008-02-01

The management of diabetic foot ulcers remains a problem. A treatment modality that uses compressed air massage has been developed as a supplement to standard surgical and medical treatment. Compressed air massage is thought to improve local tissue oxygenation around ulcers. The aim of this study was to determine whether the addition of compressed air massage influences the rate of healing of diabetic ulcers. Sixty consecutive patients with diabetes, admitted to one hospital for urgent surgical management of diabetic foot ulcers, were randomized into two groups. Both groups received standard medical and surgical management of their diabetes and ulcer. In addition, one group received 15-20 min of compressed air massage, at 1 bar pressure, daily, for 5 days a week, to the foot and the tissue around the ulcer. Healing time was calculated as the time from admission to the time of re-epithelialization. Fifty-seven patients completed the trial; 28 received compressed air massage. There was no difference in the mean age, Wagner score, ulcer size, pulse status, or peripheral sensation in the two groups. The time to healing in the compressed air massage group was significantly reduced: 58.1 +/- 22.3 days (95% confidence interval: 49.5-66.6) versus 82.7 +/- 30.7 days (95% confidence interval: 70.0-94.3) (P = 0.001). No adverse effects in response to compressed air massage were noted. The addition of compressed air massage to standard medical and surgical management of diabetic ulcers appears to enhance ulcer healing. Further studies with this new treatment modality are warranted.

Economic and environmental evaluation of compressed-air cars

International Nuclear Information System (INIS)

Creutzig, Felix; Kammen, Daniel M; Papson, Andrew; Schipper, Lee

2009-01-01

Climate change and energy security require a reduction in travel demand, a modal shift, and technological innovation in the transport sector. Through a series of press releases and demonstrations, a car using energy stored in compressed air produced by a compressor has been suggested as an environmentally friendly vehicle of the future. We analyze the thermodynamic efficiency of a compressed-air car powered by a pneumatic engine and consider the merits of compressed air versus chemical storage of potential energy. Even under highly optimistic assumptions the compressed-air car is significantly less efficient than a battery electric vehicle and produces more greenhouse gas emissions than a conventional gas-powered car with a coal intensive power mix. However, a pneumatic-combustion hybrid is technologically feasible, inexpensive and could eventually compete with hybrid electric vehicles.

Recoil Experiments Using a Compressed Air Cannon

Science.gov (United States)

Taylor, Brett

2006-01-01

Ping-Pong vacuum cannons, potato guns, and compressed air cannons are popular and dramatic demonstrations for lecture and lab. Students enjoy them for the spectacle, but they can also be used effectively to teach physics. Recently we have used a student-built compressed air cannon as a laboratory activity to investigate impulse, conservation of…

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.

Lower operating cost due to compressed-air recirculation

Energy Technology Data Exchange (ETDEWEB)

Schauwecker, F

1979-01-01

Compressed air containing dirt and aggressive substances may cause damage in pipelines and pneumatic tools, equipment and systems. In consequence, operating costs can be greatly reduced by cleaning and recirculation of compressed air. Compressed-air driers are among the most common systems used for this purpose. Most of these driers are refrigeration driers; adsorption driers are less common. Refrigeration driers consist of a heat exchanger system, a separation system, and a power-controlled refrigerator. The water vapour concentration is proportional to the air temperature; for this reason, the pressure dew point should be as low as possible, i.e. about 1.5/sup 0/C.

Investigation on wind energy-compressed air power system.

Science.gov (United States)

Jia, Guang-Zheng; Wang, Xuan-Yin; Wu, Gen-Mao

2004-03-01

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.

Compressed air energy storage system

Science.gov (United States)

Ahrens, Frederick W.; Kartsounes, George T.

1981-01-01

An internal combustion reciprocating engine is operable as a compressor during slack demand periods utilizing excess power from a power grid to charge air into an air storage reservoir and as an expander during peak demand periods to feed power into the power grid utilizing air obtained from the air storage reservoir together with combustible fuel. Preferably the internal combustion reciprocating engine is operated at high pressure and a low pressure turbine and compressor are also employed for air compression and power generation.

Improving compressed air system performance: A sourcebook for industry

OpenAIRE

Mckane, Aimee T.

2003-01-01

Compressed air is used widely throughout industry and is often considered the "fourth utility" at many facilities. Almost every industrial plant, from a small machine shop to an immense pulp and paper mill, has some type of compressed air system. In many cases, the compressed air system is so vital that the facility cannot operate without it. Plant air compressor systems can vary in size from a small unit of 5 horsepower (hp) to huge systems with more than 50,000 hp. In many industrial facili...

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.

Adiabatic Liquid Piston Compressed Air Energy Storage

DEFF Research Database (Denmark)

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

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......), but no such units are in operation at present. The CAES system investigated in this project uses a different approach to avoid compression heat loss. The system uses a pre-compressed pressure vessel full of air. A liquid is pumped into the bottom of the vessel when charging and the same liquid is withdrawn through......-CAES system is significantly higher than existing CAES systems due to a low or nearly absent compression heat loss. Furthermore, pumps/turbines, which use a liquid as a medium, are more efficient than air/gas compressors/turbines. In addition, the demand for fuel during expansion does not occur. •The energy...

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.

Compressed air system audit in a chemical company

Energy Technology Data Exchange (ETDEWEB)

Radgen, P. [Fraunhofer ISI, Karlsruhe (Germany)

2005-07-01

This paper describes the results achieved during a compressed air system audit at a chemical company in Switzerland. The aim of the audit conducted in Muttenz at the site of Clariant Schweiz AG was to analyse the installed compressed air system and its operation in order to identify energy and cost saving potentials. Because there was measurement equipment already installed, it was not necessary to install a new meter. Instead the existing data had to be extracted from the controlled system and regrouped for the analysis. Aggregated data for 2003 and 2004 and a set of detailed data acquired in the course of one week were used for the analysis. The audit identified a number of measures to improve the compressed air system, but had to conclude that the saving potentials at this site are below average. The audit included the compressors, the air treatment and air distribution up to production or storage buildings. The saving potential identified was quantified as about 300 000 kWh/a, or 13.3% of the compressed air energy demand. The cost savings were calculated to be around 41 852 Swiss Franks. (orig.)

Efficiency at Sorting Cards in Compressed Air

Science.gov (United States)

Poulton, E. C.; Catton, M. J.; Carpenter, A.

1964-01-01

At a site where compressed air was being used in the construction of a tunnel, 34 men sorted cards twice, once at normal atmospheric pressure and once at 3½, 2½, or 2 atmospheres absolute pressure. An additional six men sorted cards twice at normal atmospheric pressure. When the task was carried out for the first time, all the groups of men performing at raised pressure were found to yield a reliably greater proportion of very slow responses than the group of men performing at normal pressure. There was reliably more variability in timing at 3½ and 2½ atmospheres absolute than at normal pressure. At 3½ atmospheres absolute the average performance was also reliably slower. When the task was carried out for the second time, exposure to 3½ atmospheres absolute pressure had no reliable effect. Thus compressed air affected performance only while the task was being learnt; it had little effect after practice. No reliable differences were found related to age, to length of experience in compressed air, or to the duration of the exposure to compressed air, which was never less than 10 minutes at 3½ atmospheres absolute pressure. PMID:14180485

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

NARCIS (Netherlands)

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

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.

Performance of a hydraulic air compressor for use in compressed air energy storage power systems

Energy Technology Data Exchange (ETDEWEB)

Berghmans, J. A.; Ahrens, F. W.

1978-01-01

A fluid mechanical analysis of a hydraulic air compression system for Compressed Air Energy Storage (CAES) application is presented. With this compression concept, air is charged into an underground reservoir, for later use in power generation, by entraining bubbles into a downward flow of water from a surface reservoir. Upon releasing the air in the underground reservoir, the water is pumped back to the surface. The analytical model delineated is used to predict the hydraulic compressor performance characteristics (pumping power, pump head, compression efficiency) as a function of water flow rate and system geometrical parameters. The results indicate that, although large water pumps are needed, efficiencies as high as 90% (relative to ideal isothermal compression) can be expected. This should result in lower compression power than for conventional compressor systems, while eliminating the need for the usual intercoolers and aftercooler.

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. PMID:25379536

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.

Mathematical modeling of compression processes in air-driven boosters

International Nuclear Information System (INIS)

Li Zeyu; Zhao Yuanyang; Li Liansheng; Shu Pengcheng

2007-01-01

The compressed air in normal pressure is used as the source of power of the air-driven booster. The continuous working of air-driven boosters relies on the difference of surface area between driven piston and driving piston, i.e., the different forces acting on the pistons. When the working surface area of the driving piston for providing power is greater than that of the driven piston for compressing gas, the gas in compression chamber will be compressed. On the basis of the first law of thermodynamics, the motion regulation of piston is analyzed and the mathematical model of compression processes is set up. Giving a calculating example, the vary trends of gas pressure and pistons' move in working process of booster have been gotten. The change of parameters at different working conditions is also calculated and compared. And the corresponding results can be referred in the design of air-driven boosters

A cost-effective compressed air generation for manufacturing using modified microturbines

International Nuclear Information System (INIS)

Eret, Petr

2016-01-01

Highlights: • A new cost-effective way of compressed air generation for manufacturing in SME is proposed. • The approach is based on a modified microturbine configuration. • Thermodynamic and life cycle analyses are presented and economic benefit is demonstrated. - Abstract: Compressed air is an irreplaceable energy source for some manufacturing processes, and is also common in applications even when there are alternatives. As a result, compressed air is a key utility in manufacturing industry, but unfortunately the cost of compressed air production is one of the most expensive processes in a manufacturing facility. In order to reduce the compressed air generation cost an unconventional way using a microturbine configuration is proposed. The concept is based on an extraction of a certain amount of compressed air from/after the compressor with the residual air flowing to the turbine to produce sufficient back power to drive the compressor. A thermodynamic and life cycle analysis are presented for several system variations, including a simple cycle without a recuperator and a complex configuration with an intercooler, recuperator and reheating. The study is based on the typical requirements (i.e. quantity, pressure) for a small to medium sized industrial compressed air system. The analysis is focused on the North American market due to the low price of natural gas. The lowest life cycle cost alternative is represented by a microturbine concept with a recuperator, air extraction after partial compression, intercooler and aftercooler. A comparison of an electric motor and conventional microturbine prime movers demonstrates the economic benefit of the proposed compressed air generation method, for the design parameters and utility prices considered.

Free-beam soliton self-compression in air

Science.gov (United States)

Voronin, A. A.; Mitrofanov, A. V.; Sidorov-Biryukov, D. A.; Fedotov, A. B.; Pugžlys, A.; Panchenko, V. Ya; Shumakova, V.; Ališauskas, S.; Baltuška, A.; Zheltikov, A. M.

2018-02-01

We identify a physical scenario whereby soliton transients generated in freely propagating laser beams within the regions of anomalous dispersion in air can be compressed as a part of their free-beam spatiotemporal evolution to yield few-cycle mid- and long-wavelength-infrared field waveforms, whose peak power is substantially higher than the peak power of the input pulses. We show that this free-beam soliton self-compression scenario does not require ionization or laser-induced filamentation, enabling high-throughput self-compression of mid- and long-wavelength-infrared laser pulses within a broad range of peak powers from tens of gigawatts up to the terawatt level. We also demonstrate that this method of pulse compression can be extended to long-range propagation, providing self-compression of high-peak-power laser pulses in atmospheric air within propagation ranges as long as hundreds of meters, suggesting new ways towards longer-range standoff detection and remote sensing.

[Experimental study on spectra of compressed air microwave plasma].

Science.gov (United States)

Liu, Yong-Xi; Zhang, Gui-Xin; Wang, Qiang; Hou, Ling-Yun

2013-03-01

Using a microwave plasma generator, compressed air microwave plasma was excited under 1 - 5 atm pressures. Under different pressures and different incident microwave power, the emission spectra of compressed air microwave plasma were studied with a spectra measuring system. The results show that continuum is significant at atmospheric pressure and the characteristic will be weakened as the pressure increases. The band spectra intensity will be reduced with the falling of the incident microwave power and the band spectra were still significant. The experimental results are valuable to studying the characteristics of compressed air microwave plasma and the generating conditions of NO active groups.

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...... over thermal waves from all fibers, and by a self-consistent procedure. Figuren of the compressibility in the frequency range 10-100 000 Hz, are given for diameter of the cylinders of 6.8 µm, and mean distances between them from 50 to 110 µm, which corresponds to glass wool with a density of 40 to 16...

AF Sites

Science.gov (United States)

AF Bands Air Force Band Recordings Air National Guard Band of the Midwest Air National Guard Band of U.S. Air Force Bands U.S. Air Force Heartland of America Band U.S. Air Force Heritage of America Band U.S. Air Forces in Europe Band US Air Forces Central Command Band Medical 42d Medical Group 59th

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.

30 CFR 77.411 - Compressed air and boilers; general.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Compressed air and boilers; general. 77.411 Section 77.411 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... COAL MINES Safeguards for Mechanical Equipment § 77.411 Compressed air and boilers; general. All...

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.

Contamination of hospital compressed air with nitric oxide: unwitting replacement therapy.

Science.gov (United States)

Pinsky, M R; Genc, F; Lee, K H; Delgado, E

1997-06-01

Inhaled nitric oxide (NO) at levels between 5 and 80 ppm has been used experimentally to treat a variety of conditions. NO also is a common environmental air pollutant in industrial regions. As compressed hospital air is drawn from the local environment, we speculated that it may contain NO contamination, which, if present, would provide unwitting inhaled NO therapy to all subjects respiring this compressed gas. NO levels were measured twice daily from ambient hospital air and compressed gas sources driving positive pressure ventilation from two adjacent hospitals and compared with NO levels reported daily by local Environmental Protection Agency sources. An NO chemiluminescence analyzer (Sievers 270B; Boulder, Colo) sensitive to > or =2 parts per billion was used to measure NO levels in ambient air and compressed gas. NO levels in ambient air and hospital compressed air covaried from day to day, and absolute levels of NO differed between hospitals with the difference never exceeding 1.4 ppm (range, 0 to 1.4 ppm; median, 0.07 ppm). The hospital with the highest usage level of compressed air had the highest levels of NO, which approximated ambient levels of NO. NO levels were lowest on weekends in both hospitals. We also documented inadvertent NO contamination in one hospital occurring over 5 days, which corresponded to welding activity near the intake port for fresh gas. This contamination resulted in system-wide NO levels of 5 to 8 ppm. Hospital compressed air contains highly variable levels of NO that tend to covary with ambient NO levels and to be highest when the rate of usage is high enough to preclude natural degradation of NO in 21% oxygen. Assuming that inhaled NO may alter gas exchange, pulmonary hemodynamics, and outcome from acute lung injury, the role of unwitting variable NO of hospital compressed air needs to be evaluated.

Compressed-air power tools in orthopaedic surgery: exhaust air is a potential source of contamination.

Science.gov (United States)

Sagi, H C; DiPasquale, Thomas; Sanders, Roy; Herscovici, Dolfi

2002-01-01

To determine if the exhaust from surgical compressed-air power tools contains bacteria and if the exhaust leads to contamination of sterile surfaces. Bacteriologic study of orthopaedic power tools. Level I trauma center operative theater. None. Part I. Exhaust from two sterile compact air drills was sampled directly at the exhaust port. Part II. Exhaust from the drills was directed at sterile agar plates from varying distances. The agar plates represented sterile surfaces within the operative field. Part III. Control cultures. A battery-powered drill was operated over open agar plates in similar fashion as the compressed-air drills. Agar plates left open in the operative theater served as controls to rule out atmospheric contamination. Random cultures were taken from agar plates, gloves, drills, and hoses. Incidence of positive cultures. In Part I, all filters from both compressed-air drill exhausts were culture negative ( = 0.008). In Part II, the incidence of positive cultures for air drills number one and number two was 73% and 82%, respectively. The most commonly encountered organisms were, coagulase-negative Staphylococcus, and Micrococcus species. All control cultures from agar plates, battery-powered drill, gloves, and hoses were negative ( compressed-air power tools in orthopaedic surgery may contribute to the dissemination of bacteria onto the surgical field. We do not recommend the use of compressed-air power tools that do not have a contained exhaust.

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.

Design of a Hydraulic Motor System Driven by Compressed Air

OpenAIRE

Shaw, Dein; Yu, Jyun-Jhe; Chieh, Cheng

2013-01-01

This paper presents the design of a highly efficient pneumatic motor system. The air engine is currently the most generally used device to convert potential energy of compressed air into mechanical energy. However, the efficiency of the air engines is too low to provide sufficient operating range for the vehicle. In this study, the energy contained in compressed air/pressurized hydraulic oil is transformed by a hydraulic motor to mechanical energy to enhance the efficiency of using air power....

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

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Inspection of compressed-air receivers and... METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13015 Inspection of compressed-air receivers and other unfired pressure vessels. (a) Compressed-air receivers and other unfired pressure vessels...

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

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Inspection of compressed-air receivers and...-UNDERGROUND METAL AND NONMETAL MINES Compressed Air and Boilers § 57.13015 Inspection of compressed-air receivers and other unfired pressure vessels. (a) Compressed-air receivers and other unfired pressure...

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.

On the estimation method of compressed air consumption during pneumatic caisson sinking

OpenAIRE

平川, 修治; ヒラカワ, シュウジ; Shuji, HIRAKAWA

1990-01-01

There are several methods in estimation of compressed air consumption during pneumatic caisson sinking. It is re uired in the estimation of compressed air consumption by the methods under the same conditions. In this paper, it is proposed the methods which is able to estimate accurately the compressed air consumption during pnbumatic caissons sinking at this moment.

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)

Operability test procedure for 241-U compressed air system and heat pump

International Nuclear Information System (INIS)

Freeman, R.D.

1994-01-01

The 241-U-701 compressed air system supplies instrument quality compressed air to Tank Farm 241-U. The supply piping to the 241-U Tank Farm is not included in the modification. Modifications to the 241-U-701 compressed air system include installation of a 15 HP Reciprocating Air Compressor, Ingersoll-Rand Model 10T3NLM-E15; an air dryer, Hankinson, Model DH-45; and miscellaneous system equipment and piping (valves, filters, etc.) to meet the design. A newly installed heat pump allows the compressor to operate within an enclosed relatively dust free atmosphere and keeps the compressor room within a standard acceptable temperature range, which makes possible efficient compressor operation, reduces maintenance, and maximizes compressor operating life. This document is an Operability Test Procedure (OTP) which will further verify (in addition to the Acceptance Test Procedure) that the 241-U-701 compressed air system and heat pump operate within their intended design parameters. The activities defined in this OTP will be performed to ensure the performance of the new compressed air system will be adequate, reliable and efficient. Completion of this OTP and sign off of the OTP Acceptance of Test Results is necessary for turnover of the compressed air system from Engineering to Operations

The function profile of compressed-air and ultrasonic nebulizers.

Science.gov (United States)

Wu, Hsin-Lin; Lin, Yung-Zen; Wu, Wei-Fong; Huang, Fu-Yuan

2003-01-01

In order to study the detailed function of two kinds of nebulizers commonly used in clinical asthma treatment, compressed-air and ultrasonic, this study was conducted. At the beginning, various flow rates were adjusted, paired with different volumes of solutions in the container. The changes of temperature, pH, and osmolality during the course of nebulization were examined. Normal saline, terbutaline, and fenoterol solutions were used as the nebulized solutions. The study was performed in an environment in ambient temperature around 20 degrees C and relative humidity around 70%. The results showed a minimal 6 L/min flow rate was required to nebulize the solution when using the compressed-air nebulizer. The dead volume was about 0.8 ml for compressed-air and 8.5 ml for the ultrasonic nebulizer. When using the compressed-air nebulizer, the temperature, both in the solution and at the mouthpiece site, dropped gradually. On the contrary, the temperatures at both sites increased a little bit when using the ultrasonic nebulizer. The pH values of pure terbutaline and fenoterol nebulized solutions were acidic (3.58 and 3.00 respectively). The osmolality of terbutaline and fenoterol nebulized solutions were isotonic. The osmolality increased gradually during the course of nebulization, to a greater extent in the compressed-air nebulizer. In conclusion, both types of nebulizers have their special features. The ultrasonic nebulizer displays less extent in change of temperature and osmolality during nebulization and is expected to be a better device in treating asthmatic patients in terms of lesser effect on cooling and changing the osmolality of airway mucosa.

Air Compressibility Effect on Bouwer and Rice Seepage Meter.

Science.gov (United States)

Peng, Xin; Zhan, Hongbin

2017-11-01

Measuring a disconnected streambed seepage flux using a seepage meter can give important streambed information and help understanding groundwater-surface water interaction. In this study, we provide a correction for calculating the seepage flux rate with the consideration of air compressibility inside the manometer of the Bouwer and Rice seepage meter. We notice that the effect of air compressibility in the manometer is considerably larger when more air is included in the manometer. We find that the relative error from neglecting air compressibility can be constrained within 5% if the manometer of the Bouwer and Rice seepage meter is shorter than 0.8 m and the experiment is done in a suction mode in which air is pumped out from the manometer before the start of measurement. For manometers longer than 0.8 m, the relative error will be larger than 5%. It may be over 10% if the manometer height is longer than 1.5 m and the experiment is done in a no-suction mode, in which air is not pumped out from the manometer before the start of measurement. © 2017, National Ground Water Association.

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... Use of Explosives § 1926.913 Blasting in excavation work under compressed air. (a) Detonators and... connecting wires are connected up. (b) When detonators or explosives are brought into an air lock, no...

Compressed air as a source of inhaled oxidants in intensive care units.

Science.gov (United States)

Thibeault, D W; Rezaiekhaligh, M H; Ekekezie, I; Truog, W E

1999-01-01

Exhaled gas from mechanically ventilated preterm infants was found to have similar oxidant concentrations, regardless of lung disease, leading to the hypothesis that wall outlet gases were an oxidant source. Oxidants in compressed room air and oxygen from wall outlets were assessed in three hospitals. Samples were collected by flowing wall outlet gas through a heated humidifier and an ice-packed condenser. Nitric oxide (NO) was measured in intensive care room air and in compressed air with and without a charcoal filter using a Sievers NOA280 nitric oxide analyzer (Boulder, CO). Oxidants were measured by spectrophotometry and expressed as nMol equivalents of H2O2/mL. The quantity of oxidant was also expressed as amount of Vitamin C (nMol/mL) added until the oxidant was nondetectable. This quantity of Vitamin C was also expressed in Trolox Equivalent Antioxidant Capacity (TEAC) units (mMol/L). Free and total chlorine were measured with a Chlorine Photometer. Oxidants were not found in compressed oxygen and were only found in compressed air when the compression method used tap water. At a compressed room air gas flow of 1.5 L/min, the total volume of condensate was 20.2 +/- 1 mL/hr. The oxidant concentration was 1.52 +/- 0.09 nMol/mL equivalents of H2O2/mL of sample and 30.8 +/- 1.2 nMol/hr; 17.9% of that found in tap water. Oxidant reduction required 2.05 +/-0.12 nMol/mL vitamin C, (1.78 +/- 0.1 x 10(-3) TEAC units). Free and total chlorine in tap water were 0.3 +/- 0.02 mg/mL and 2.9 +/- 0.002 mg/mL, respectively. Outlet gas contained 0.4 +/- 0.06 mg/mL and 0.07 + 0.01 mg/mL total and free chlorine, respectively; both 14% of tap water. When a charcoal filter was installed in the hospital with oxidants in compressed air, oxidants were completely removed. Nursery room air contained 12.4 +/- 0.5 ppb NO; compressed wall air without a charcoal filter, 8.1 +/- 0.1 ppb and compressed air with a charcoal filter 12.5 +/- 0.5 ppb. A charcoal filter does not remove NO. (Table

The Design of Compressed air system in the Conventional Facility of Proton Accelerator Research Center

International Nuclear Information System (INIS)

Jeon, G. P.; Kim, J. Y.; Cho, S. W.; Min, Y. S.; Mun, K. J.; Cho, J. S.; Nam, J. M.; Park, S. S.; Jo, J. H.

2012-01-01

The Compressed Air System (CA) supplies compressed air for all air operated devices and instruments, pneumatic equipment and other miscellaneous air user points in the Conventional Facilities of Proton Engineering Frontier Project. CA System consist of the Instrument Air System and the Service air System. The Instrument Air System supplies oil-free, dried, filtered, and compressed instrument air for the air operated control devices and instruments in the Accelerator and Beam Application Building, Ion Beam Application Building, Utility Building and etc.. The Service air System supplies compressed air for pneumatic equipment and other services

Rupture of sigmoid colon caused by compressed air.

Science.gov (United States)

Yin, Wan-Bin; Hu, Ji-Lin; Gao, Yuan; Zhang, Xian-Xiang; Zhang, Mao-Shen; Liu, Guang-Wei; Zheng, Xue-Feng; Lu, Yun

2016-03-14

Compressed air has been generally used since the beginning of the 20(th) century for various applications. However, rupture of the colon caused by compressed air is uncommon. We report a case of pneumatic rupture of the sigmoid colon. The patient was admitted to the emergency room complaining of abdominal pain and distention. His colleague triggered a compressed air nozzle against his anus as a practical joke 2 h previously. On arrival, his pulse rate was 126 beats/min, respiratory rate was 42 breaths/min and blood pressure was 86/54 mmHg. Physical examination revealed peritoneal irritation and the abdomen was markedly distended. Computed tomography of the abdomen showed a large volume of air in the abdominal cavity. Peritoneocentesis was performed to relieve the tension pneumoperitoneum. Emergency laparotomy was done after controlling shock. Laparotomy revealed a 2-cm perforation in the sigmoid colon. The perforation was sutured and temporary ileostomy was performed as well as thorough drainage and irrigation of the abdominopelvic cavity. Reversal of ileostomy was performed successfully after 3 mo. Follow-up was uneventful. We also present a brief literature review.

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.

Cerebral magnetic resonance imaging of compressed air divers in diving accidents.

Science.gov (United States)

Gao, G K; Wu, D; Yang, Y; Yu, T; Xue, J; Wang, X; Jiang, Y P

2009-01-01

To investigate the characteristics of the cerebral magnetic resonance imaging (MRI) of compressed air divers in diving accidents, we conducted an observational case series study. MRI of brain were examined and analysed on seven cases compressed air divers complicated with cerebral arterial gas embolism CAGE. There were some characteristics of cerebral injury: (1) Multiple lesions; (2) larger size; (3) Susceptible to parietal and frontal lobe; (4) Both cortical grey matter and subcortical white matter can be affected; (5) Cerebellum is also the target of air embolism. The MRI of brain is an sensitive method for detecting cerebral lesions in compressed air divers in diving accidents. The MRI should be finished on divers in diving accidents within 5 days.

The investigation on compressed air quality analysis results of nuclear power plants

International Nuclear Information System (INIS)

Sung, K. B.; Kim, H. K.; Kim, W. S.

2000-01-01

The compressed air system of nuclear power plants provides pneumatic power for both operation and control of various plant equipment, tools, and instrumentation. Included in the air supply systems are the compressors, coolers, moisture separators, dryers, filters and air receiver tanks that make up the major items of equipment. The service air system provides oil-free compressed air for general plant and maintenance use and the instrument air system provides dry, oil-free, compressed air for both nonessential and essential components and instruments. NRC recommended the periodic checks on GL88-14 'Instrument air supply system problems affecting safety-related equipment'. To ensure that the quality of the instrument air is equivalent to or exceeds the requirement s of ISA-S7.3(1975), air samples are taken at every refueling outage and analyzed for moisture, oil and particulate content. The over all results are satisfied the requirements of ISA-S7.3

Orbital compressed air and petroleum injury mimicking necrotizing fasciitis.

Science.gov (United States)

Mellington, Faye E; Bacon, Annette S; Abu-Bakra, Mohammed A J; Martinez-Devesa, Pablo; Norris, Jonathan H

2014-09-01

Orbital injury secondary to petroleum-based products is rare. We report the first case, to our knowledge, of a combined compressed air and chemical orbital injury, which mimicked necrotizing fasciitis. A 58-year-old man was repairing his motorcycle engine when a piston inadvertently fired, discharging compressed air and petroleum-based carburetor cleaner into his left eye. He developed surgical emphysema, skin necrosis, and a chemical cellulitis, causing an orbital compartment syndrome. He was treated initially with antibiotics and subsequently with intravenous steroid and orbital decompression surgery. There was almost complete recovery by 4 weeks postsurgery. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Petroleum-based products can cause severe skin irritation and necrosis. Compressed air injury can cause surgical emphysema. When these two mechanisms of injury are combined, the resulting orbitopathy and skin necrosis can mimic necrotizing fasciitis and cause diagnostic confusion. A favorable outcome is achievable with aggressive timely management. Copyright © 2014 Elsevier Inc. All rights reserved.

Compressed air injection technique to standardize block injection pressures.

Science.gov (United States)

Tsui, Ban C H; Li, Lisa X Y; Pillay, Jennifer J

2006-11-01

Presently, no standardized technique exists to monitor injection pressures during peripheral nerve blocks. Our objective was to determine if a compressed air injection technique, using an in vitro model based on Boyle's law and typical regional anesthesia equipment, could consistently maintain injection pressures below a 1293 mmHg level associated with clinically significant nerve injury. Injection pressures for 20 and 30 mL syringes with various needle sizes (18G, 20G, 21G, 22G, and 24G) were measured in a closed system. A set volume of air was aspirated into a saline-filled syringe and then compressed and maintained at various percentages while pressure was measured. The needle was inserted into the injection port of a pressure sensor, which had attached extension tubing with an injection plug clamped "off". Using linear regression with all data points, the pressure value and 99% confidence interval (CI) at 50% air compression was estimated. The linearity of Boyle's law was demonstrated with a high correlation, r = 0.99, and a slope of 0.984 (99% CI: 0.967-1.001). The net pressure generated at 50% compression was estimated as 744.8 mmHg, with the 99% CI between 729.6 and 760.0 mmHg. The various syringe/needle combinations had similar results. By creating and maintaining syringe air compression at 50% or less, injection pressures will be substantially below the 1293 mmHg threshold considered to be an associated risk factor for clinically significant nerve injury. This technique may allow simple, real-time and objective monitoring during local anesthetic injections while inherently reducing injection speed.

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)

1993-12-31

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.

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.

Compressed-air and backup nitrogen systems in nuclear power plants

International Nuclear Information System (INIS)

Hagen, E.W.

1982-07-01

This report reviews and evaluates the performance of the compressed-air and pressurized-nitrogen gas systems in commercial nuclear power units. The information was collected from readily available operating experiences, licensee event reports, system designs in safety analysis reports, and regulatory documents. The results are collated and analyzed for significance and impact on power plant safety performance. Under certain circumstances, the fail-safe philosophy for a piece of equipment or subsystem of the compressed-air systems initiated a series of actions culminating in reactor transient or unit scram. However, based on this study of prevailing operating experiences, reclassifying the compressed-gas systems to a higher safety level will neither prevent (nor mitigate) the reoccurrences of such happenings nor alleviate nuclear power plant problems caused by inadequate maintenance, operating procedures, and/or practices. Conversely, because most of the problems were derived from the sources listed previously, upgrading of both maintenance and operating procedures will not only result in substantial improvement in the performance and availability of the compressed-air (and backup nitrogen) systems but in improved overall plant performance

A new compressed air energy storage refrigeration system

International Nuclear Information System (INIS)

Wang Shenglong; Chen Guangming; Fang Ming; Wang Qin

2006-01-01

In this study, a new compressed air energy storage (CAES) refrigeration system is proposed for electrical power load shifting application. It is a combination of a gas refrigeration cycle and a vapor compression refrigeration cycle. Thermodynamic calculations are conducted to investigate the performance of this system. Economic analysis is performed to study the operating cost of the system, and comparison is made with a vapor compression refrigeration system and an ice storage refrigeration system. The results indicate that the CAES refrigeration system has the advantages of simple structure, high efficiency and low operating cost

Compressed air production with waste heat utilization in industry

Science.gov (United States)

Nolting, E.

1984-06-01

The centralized power-heat coupling (PHC) technique using block heating power stations, is presented. Compressed air production in PHC technique with internal combustion engine drive achieves a high degree of primary energy utilization. Cost savings of 50% are reached compared to conventional production. The simultaneous utilization of compressed air and heat is especially interesting. A speed regulated drive via an internal combustion motor gives a further saving of 10% to 20% compared to intermittent operation. The high fuel utilization efficiency ( 80%) leads to a pay off after two years for operation times of 3000 hr.

Operability Test Report for 241-U Compressed Air System and heat pump

International Nuclear Information System (INIS)

Rensink, G.E.

1995-01-01

The 241-U-701 compressed air system supplies instrument quality compressed air to Tank Farm 241-U. The system was upgraded. The operability test showed that the system operates within its intended design parameters. System performance was monitored, recorded, and used to identify areas of concern. Exceptions to the OTP and additional items for safe system performance were minimal and have been resolved; the air system is ready for Operation's use

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.

Compressed-air flow control system.

Science.gov (United States)

Bong, Ki Wan; Chapin, Stephen C; Pregibon, Daniel C; Baah, David; Floyd-Smith, Tamara M; Doyle, Patrick S

2011-02-21

We present the construction and operation of a compressed-air driven flow system that can be used for a variety of microfluidic applications that require rapid dynamic response and precise control of multiple inlet streams. With the use of inexpensive and readily available parts, we describe how to assemble this versatile control system and further explore its utility in continuous- and pulsed-flow microfluidic procedures for the synthesis and analysis of microparticles.

Automated control of a solar microgrid-powered air compressor for use in a small-scale compressed air energy storage system

OpenAIRE

Williams, Joshua N.

2017-01-01

Approved for public release; distribution is unlimited As part of the Office of Naval Research's study of advanced energy technologies, this research examined the development and implementation of a control system for the compression phase of a small-scale compressed air energy storage system, using a solar-powered microgrid to store energy as compressed air for later use. The compression system is composed of numerous commercial-off-the-shelf components wherever possible. All electronic c...

Compressed Air Quality, A Case Study In Paiton Coal Fired Power Plant Unit 1 And 2

Science.gov (United States)

Indah, Nur; Kusuma, Yuriadi; Mardani

2018-03-01

The compressed air system becomes part of a very important utility system in a Plant, including the Steam Power Plant. In PLN’S coal fired power plant, Paiton units 1 and 2, there are four Centrifugal air compressor types, which produce compressed air as much as 5.652 cfm and with electric power capacity of 1200 kW. Electricity consumption to operate centrifugal compressor is 7.104.117 kWh per year. Compressed air generation is not only sufficient in quantity (flow rate) but also meets the required air quality standards. compressed air at Steam Power Plant is used for; service air, Instrument air, and for fly Ash. This study aims to measure some important parameters related to air quality, followed by potential disturbance analysis, equipment breakdown or reduction of energy consumption from existing compressed air conditions. These measurements include counting the number of dust particles, moisture content, relative humidity, and also compressed air pressure. From the measurements, the compressed air pressure generated by the compressor is about 8.4 barg and decreased to 7.7 barg at the furthest point, so the pressure drop is 0.63 barg, this number satisfies the needs in the end user. The measurement of the number of particles contained in compressed air, for particle of 0.3 micron reaches 170,752 particles, while for the particle size 0.5 micron reaches 45,245 particles. Measurements of particles conducted at several points of measurement. For some point measurements the number of dust particle exceeds the standard set by ISO 8573.1-2010 and also NACE Code, so it needs to be improved on the air treatment process. To see the amount of moisture content in compressed air, it is done by measuring pressure dew point temperature (PDP). Measurements were made at several points with results ranging from -28.4 to 30.9 °C. The recommendation of improving compressed air quality in steam power plant, Paiton unit 1 and 2 has the potential to extend the life of

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)...

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.

Design of a Hydraulic Motor System Driven by Compressed Air

Directory of Open Access Journals (Sweden)

Jyun-Jhe Yu

2013-06-01

Full Text Available This paper presents the design of a highly efficient pneumatic motor system. The air engine is currently the most generally used device to convert potential energy of compressed air into mechanical energy. However, the efficiency of the air engines is too low to provide sufficient operating range for the vehicle. In this study, the energy contained in compressed air/pressurized hydraulic oil is transformed by a hydraulic motor to mechanical energy to enhance the efficiency of using air power. To evaluate the theoretical efficiency, the principle of balance of energy is applied. The theoretical efficiency of converting air into hydraulic energy is found to be a function of pressure; thus, the maximum converting efficiency can be determined. To confirm the theoretical evaluation, a prototype of the pneumatic hydraulic system is built. The experiment verifies that the theoretical evaluation of the system efficiency is reasonable, and that the layout of the system is determined by the results of theoretical evaluation.

Compressed air-assisted solvent extraction (CASX) for metal removal.

Science.gov (United States)

Li, Chi-Wang; Chen, Yi-Ming; Hsiao, Shin-Tien

2008-03-01

A novel process, compressed air-assisted solvent extraction (CASX), was developed to generate micro-sized solvent-coated air bubbles (MSAB) for metal extraction. Through pressurization of solvent with compressed air followed by releasing air-oversaturated solvent into metal-containing wastewater, MSAB were generated instantaneously. The enormous surface area of MSAB makes extraction process extremely fast and achieves very high aqueous/solvent weight ratio (A/S ratio). CASX process completely removed Cr(VI) from acidic electroplating wastewater under A/S ratio of 115 and extraction time of less than 10s. When synthetic wastewater containing Cd(II) of 50mgl(-1) was treated, A/S ratios of higher than 714 and 1190 could be achieved using solvent with extractant/diluent weight ratio of 1:1 and 5:1, respectively. Also, MSAB have very different physical properties, such as size and density, compared to the emulsified solvent droplets, making separation and recovery of solvent from treated effluent very easy.

Colorectal injury by compressed air: the rule of conservative therapy

Directory of Open Access Journals (Sweden)

Labib Al-Ozaibi

2017-01-01

Full Text Available We are reporting a case of colorectal injury caused by a jet of compressed air directed from a distance towards the anus. The patient mentioned that it happened accidentally while his colleague was cleaning his clothes using compressed air. The patient presented with acute abdominal pain and distension. A contrast CT study did not show any free air or leakage. The patient was treated conservatively, progressed well and was discharged from the hospital on the fourth day. Resumo: Descrevemos um caso de lesão colorretal causada por um jato de ar comprimido direcionado para o ânus, a certa distância. O paciente mencionou que o ocorrido foi acidental, enquanto um colega estava limpando suas roupas com ar comprimido. O paciente se apresentou com dores abdominais agudas e distensão. Um estudo de TC contrastado não demonstrou ar livre, nem vazamento. O paciente foi tratado conservadoramente, teve boa evolução e recebeu alta hospitalar no quarto dia. Keywords: Compressed air colon injury, Colon barotrauma, Pneumatic bowel injury, Palavras-chave: Lesão de colon por ar comprimido, Barotrauma de colon, Lesão intestinal pneumática

Chapter 22: Compressed Air Evaluation Protocol. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures

Energy Technology Data Exchange (ETDEWEB)

Kurnik, Charles W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Benton, Nathanael [Nexant, Inc., San Francisco, CA (United States); Burns, Patrick [Nexant, Inc., San Francisco, CA (United States)

2017-10-18

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, load/unload, or constant-speed compressor; and 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.

Transconjunctival orbital emphysema caused by compressed air injury: a case report.

Science.gov (United States)

Mathew, Sunu; Vasu, Usha; Francis, Febson; Nazareth, Colin

2008-01-01

Orbital emphysema following conjunctival tear in the absence of orbital wall fracture, caused by air under pressure is rare. Usually orbital emphysema is seen in facial trauma associated with damage to the adjacent paranasal sinuses or facial bones. To the best of our knowledge, there have been only eight reports of orbital emphysema following use of compressed air during industrial work. The air under pressure is pushed through the subconjunctival space into the subcutaneous and retrobulbar spaces. We present here a rare cause of orbital emphysema in a young man working with compressed air gun. Although the emphysema was severe, there were no orbital bone fracture and the visual recovery of the patient was complete without attendant complications.

Self contained compressed air breathing apparatus to facilitate personnel decontamination

International Nuclear Information System (INIS)

McDonald, C.W.

1963-11-01

This report describes the modification of a Self Contained Compressed Air Breathing Apparatus to provide extended respiratory protection to grossly contaminated personnel during a decontamination period which may exceed the duration of the Breathing Apparatus air supply. (author)

Self contained compressed air breathing apparatus to facilitate personnel decontamination

Energy Technology Data Exchange (ETDEWEB)

McDonald, C W [Radiological and Safety Division, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

1963-11-15

This report describes the modification of a Self Contained Compressed Air Breathing Apparatus to provide extended respiratory protection to grossly contaminated personnel during a decontamination period which may exceed the duration of the Breathing Apparatus air supply. (author)

Compressed-air work is entering the field of high pressures.

Science.gov (United States)

Le Péchon, J Cl; Gourdon, G

2010-01-01

Since 1850, compressed-air work has been used to prevent shafts or tunnels under construction from flooding. Until the 1980s, workers were digging in compressed-air environments. Since the introduction of tunnel boring machines (TBMs), very little digging under pressure is needed. However, the wearing out of cutter-head tools requires inspection and repair. Compressed-air workers enter the pressurized working chamber only occasionally to perform such repairs. Pressures between 3.5 and 4.5 bar, that stand outside a reasonable range for air breathing, were reached by 2002. Offshore deep diving technology had to be adapted to TBM work. Several sites have used mixed gases: in Japan for deep shaft sinking (4.8 bar), in The Netherlands at Western Scheldt Tunnels (6.9 bar), in Russia for St. Petersburg Metro (5.8 bar) and in the United States at Seattle (5.8 bar). Several tunnel projects are in progress that may involve higher pressures: Hallandsås (Sweden) interventions in heliox saturation up to 13 bar, and Lake Mead (U.S.) interventions to about 12 bar (2010). Research on TBMs and grouting technologies tries to reduce the requirements for hyperbaric works. Adapted international rules, expertise and services for saturation work, shuttles and trained personnel matching industrial requirements are the challenges.

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.

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

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

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.

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)

Choice of compressed air fed system of a uranium mine

International Nuclear Information System (INIS)

Li Congkui; Lei Zeyong

2006-01-01

The selection of compressed air fed system in a uranium mine is discussed. The research indicates that the movable air compressor is better than the fixed one in energy saving, once capital cost and operational cost when it is applied in an underground uranium mine. (authors)

Accelerated Air-coupled Ultrasound Imaging of Wood Using Compressed Sensing

Directory of Open Access Journals (Sweden)

Yiming Fang

2015-12-01

Full Text Available Air-coupled ultrasound has shown excellent sensitivity and specificity for the nondestructive imaging of wood-based material. However, it is time-consuming, due to the high scanning density limited by the Nyquist law. This study investigated the feasibility of applying compressed sensing techniques to air-coupled ultrasound imaging, aiming to reduce the number of scanning lines and then accelerate the imaging. Firstly, an undersampled scanning strategy specified by a random binary matrix was proposed to address the limitation of the compressed sensing framework. The undersampled scanning can be easily implemented, while only minor modification was required for the existing imaging system. Then, discrete cosine transform was selected experimentally as the representation basis. Finally, orthogonal matching pursuit algorithm was utilized to reconstruct the wood images. Experiments on three real air-coupled ultrasound images indicated the potential of the present method to accelerate air-coupled ultrasound imaging of wood. The same quality of ACU images can be obtained with scanning time cut in half.

Compressed Air Working in Chennai During Metro Tunnel Construction: Occupational Health Problems.

Science.gov (United States)

Kulkarni, Ajit C

2017-01-01

Chennai metropolis has been growing rapidly. Need was felt of a metro rail system. Two corridors were planned. Corridor 1, of 23 km starting from Washermanpet to Airport. 14.3 km of this would be underground. Corridor 2, of 22 km starting from Chennai Central Railway station to St. Thomas Mount. 9.7 km of this would be underground. Occupational health centre's role involved selection of miners and assessing their fitness to work under compressed air. Planning and execution of compression and decompression, health monitoring and treatment of compression related illnesses. More than thirty five thousand man hours of work was carried out under compressed air pressure ranged from 1.2 to 1.9 bar absolute. There were only three cases of pain only ( Type I) decompression sickness which were treated with recompression. Vigilant medical supervision, experienced lock operators and reduced working hours under pressure because of inclement environmental conditions viz. high temperature and humidity, has helped achieve this low incident. Tunnelling activity will increase in India as more cities will soon opt for underground metro railway. Indian standard IS 4138 - 1977 " Safety code for working in compressed air" needs to be updated urgently keeping pace with modern working methods.

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 (ICAES^TM) 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.

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.

Compressed air tunneling and caisson work decompression procedures: development, problems, and solutions.

Science.gov (United States)

Kindwall, E P

1997-01-01

Multinational experience over many years indicates that all current air decompression schedules for caisson and compressed air tunnel workers are inadequate. All of them, including the Occupational Safety and Health Administration tables, produce dysbaric osteonecrosis. The problem is compounded because decompression sickness (DCS) tends to be underreported. Permanent damage in the form of central nervous system or brain damage may occur in compressed air tunnel workers, as seen on magnetic resonance imaging, in addition to dysbaric osteonecrosis. Oxygen decompression seems to be the only viable method for safely decompressing tunnel workers. Oxygen decompression of tunnel workers has been successfully used in Germany, France, and Brazil. In Germany, only oxygen decompression of compressed air workers is permitted. In our experience, U.S. Navy tables 5 and 6 usually prove adequate to treat DCS in caisson workers despite extremely long exposure times, allowing patients to return to work following treatment for DCS. Tables based on empirical data and not on mathematical formulas seem to be reasonably safe. U.S. Navy Exceptional Exposure Air Decompression tables are compared with caisson tables from the United States and Great Britain.

Safety in the use of compressed air versus oxygen for the ophthalmic patient.

Science.gov (United States)

Rodgers, Laura A; Kulwicki, Anahid

2002-02-01

Oxygen, routinely administered during surgery to avoid hypoxia, poses risks including increased likelihood of surgical room fires and predisposition to retinal phototoxicity in patients. Compressed air to supplement ventilation may be safer than oxygen. The purpose of this study was to determine whether hypoxia occurs more frequently when compressed air replaces supplemental oxygen during ophthalmic surgery. A convenience sample of 111 patients was randomly assigned to receive supplemental oxygen (group 1) or compressed air (group 2). Patients with serious cardiac or pulmonary disease were excluded. Blood oxygen levels were monitored during surgery by pulse oximetry. Oxygen was administered to all group 2 patients whose oxygen saturation fell to less than 90% or by more than 5% below baseline. No differences were observed between groups in age, ASA classification, type of surgery, or anesthetic drugs or doses. Minor, but statistically higher oxygen values were observed in group 1. The frequency with which oxygen saturation decreased below 90% or below 5% of baseline was similar in both groups. Supplemental oxygen is not required routinely in selected patients undergoing ophthalmic surgery. By using compressed air, the risk of operating room fires and retinal phototoxicity may be reduced.

Compressed air energy storage with waste heat export: An Alberta case study

International Nuclear Information System (INIS)

Safaei, Hossein; Keith, David W.

2014-01-01

Highlights: • Export of compression waste heat from CAES facilities for municipal heating can be profitable. • D-CAES concept has a negative abatement cost of −$40/tCO 2 e under the studied circumstances. • Economic viability of D-CAES highly depends on distance between air storage site and heat load. - Abstract: Interest in compressed air energy storage (CAES) technology has been renewed driven by the need to manage variability form rapidly growing wind and solar capacity. Distributed CAES (D-CAES) design aims to improve the efficiency of conventional CAES through locating the compressor near concentrated heating loads so capturing additional revenue through sales of compression waste heat. A pipeline transports compressed air to the storage facility and expander, co-located at some distance from the compressor. The economics of CAES are strongly dependant on electricity and gas markets in which they are embedded. As a case study, we evaluated the economics of two hypothetical merchant CAES and D-CAES facilities performing energy arbitrage in Alberta, Canada using market data from 2002 to 2011. The annual profit of the D-CAES plant was $1.3 million more on average at a distance of 50 km between the heat load and air storage sites. Superior economic and environmental performance of D-CAES led to a negative abatement cost of −$40/tCO 2 e. We performed a suite of sensitivity analyses to evaluate the impact of size of heat load, size of air storage, ratio of expander to compressor size, and length of pipeline on the economic feasibility of D-CAES

Acceptance Test Report for 241-U compressed air system

International Nuclear Information System (INIS)

Freeman, R.D.

1994-01-01

This Acceptance Test Report (ATR) documents the results of acceptance testing of a newly upgraded compressed air system at 241-U Farm. The system was installed and the test successfully performed under work package 2W-92-01027

Design of a compressed air energy storage system for hydrostatic wind turbines

Directory of Open Access Journals (Sweden)

Ammar E. Ali

2018-03-01

Full Text Available Integration of Compressed Air Energy Storage (CAES system with a wind turbine is critical in optimally harvesting wind energy given the fluctuating nature of power demands. Here we consider the design of a CAES for a wind turbine with hydrostatic powertrain. The design parameters of the CAES are determined based on simulation of the integrated system model for a combination of these parameter values, namely the compression ratios of the air compressors and the expanders and the air tank size. The results of the simulations were used to choose the best design parameters, which would produce the best stable performance through increased energy output of the integrated CAES and wind turbine based on the intermittent wind profile. Simulation results for a 600 kW rated power wind turbine with integrated CAES indicate that increasing the tank size and compression ratio will improve the overall power quality through increased energy output up to a limit beyond which the power quality exhibits only marginal improvement.

Modelling studies for influence factors of gas bubble in compressed air energy storage in aquifers

International Nuclear Information System (INIS)

Guo, Chaobin; Zhang, Keni; Li, Cai; Wang, Xiaoyu

2016-01-01

CAES (Compressed air energy storage) is credited with its potential ability for large-scale energy storage. Generally, it is more convenient using deep aquifers than employing underground caverns for energy storage, because of extensive presence of aquifers. During the first stage in a typical process of CAESA (compressed air energy storage in aquifers), a large amount of compressed air is injected into the target aquifer to develop an initial space (a gas bubble) for energy storage. In this study, numerical simulations were conducted to investigate the influence of aquifer's permeability, geological structure and operation parameters on the formation of gas bubble and the sustainability for the later cycling operation. The SCT (system cycle times) was designed as a parameter to evaluate the reservoir performance and the effect of operation parameters. Simulation results for pressure and gas saturation results of basic model confirm the feasibility of compressed air energy storage in aquifers. The results of different permeability cases show that, for a certain scale of CAESA system, there is an optimum permeability range for a candidate aquifer. An aquifer within this permeability range will not only satisfy the injectivity requirement but also have the best energy efficiency. Structural impact analysis indicates that the anticline structure has the best performance to hold the bubble under the same daily cycling schedule with the same initial injected air mass. In addition, our results indicate that the SCT shows a logarithmic growth as the injected air mass increase. During the formation of gas bubble, compressed air should be injected into aquifers with moderate rate and the injection can be done in several stages with different injection rate to avoid onset pressure. - Highlights: • Impact of permeability, geological structure, operation parameters was investigated. • With certain air production rate, an optimum permeability exists for performance. �

Use of phase change materials during compressed air expansion for isothermal CAES plants

Science.gov (United States)

Castellani, B.; Presciutti, A.; Morini, E.; Filipponi, M.; Nicolini, A.; Rossi, F.

2017-11-01

Compressed air energy storage (CAES) plants are designed to store compressed air into a vessel or in an underground cavern and to expand it in an expansion turbine when energy demand is high. An innovative CAES configuration recently proposed is the isothermal process. Several methods to implement isothermal CAES configuration are under investigation. In this framework, the present paper deals with the experimental testing of phase change materials (PCM) during compressed air expansion phase. The experimental investigation was carried out by means of an apparatus constituted by a compression section, a steel pressure vessel, to which an expansion valve is connected. The initial internal absolute pressure was equal to 5 bar to avoid moisture condensation and the experimental tests were carried out with two paraffin-based PCM amounts (0.05 kg and 0.1 kg). Results show that the temperature change during air expansion decreases with increasing the PCM amount inside the vessel. With the use of PCM during expansions an increase of the expansion work occurs. The increase is included in the range from 9.3% to 18.2%. In every test there is an approach to the isothermal values, which represent the maximum theoretical value of the obtainable expansion work.

Improving Compressed Air System Performance: A Sourcebook for Industry

Energy Technology Data Exchange (ETDEWEB)

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.

Experience with compressed air system of Dhruva and Cirus

International Nuclear Information System (INIS)

Shelar, V.G.; Patil, U.D.; Singh, V.K.; Zope, A.K.; Kharpate, A.V.

2006-01-01

Dhruva and Cirus reactors have independent compressed air plants with provision for sharing. Dhruva has the reciprocating oil free air compressors where as Cirus has oil lubricated compressors. Over the years, several improvements have been done in the equipments to combat various problems, among these noise mitigation in Dhruva and measures to extend life of compressors in Cirus and also incidence of discharge header catching fire are interesting. This paper details these experiences. (author)

Colorectal injury by compressed air--a report of 2 cases.

Science.gov (United States)

Suh, H. H.; Kim, Y. J.; Kim, S. K.

1996-01-01

We report two colorectal trauma patients whose rectosigmoid region was ruptured due to a jet of compressed air directed to their anus while they were playing practical jokes with their colleagues in their place of work. It was difficult to diagnose in one patient due to vague symptoms and signs and due to being stunned by a stroke of the compressed air. Both patients suffered from abdominal pain and distension, tension pneumoperitoneum and mild respiratory alkalosis. One patient was treated with primary two layer closure, and the other with primary two layer closure and sigmoid loop colostomy. Anorectal manometry and transanal ultrasonography checked 4 weeks after surgery, revealed normal anorectal function and anatomy. The postoperative courses were favorable without any wound infection or intraabdominal sepsis. PMID:8835767

Increasing Lift by Releasing Compressed Air on Suction Side of Airfoil

Science.gov (United States)

Seewald, F

1927-01-01

The investigation was limited chiefly to the region of high angles of attack since it is only in this region that any considerable change in the character of the flow can be expected from such artificial aids. The slot, through which compressed air was blown, was formed by two pieces of sheet steel connected by screws at intervals of about 5 cm. It was intended to regulate the width of the slot by means of these screws. Much more compressed air was required than was originally supposed, hence all the delivery pipes were much too small. This experiment, therefore, is to be regarded as only a preliminary one.

Compressed air noise reductions from using advanced air gun nozzles in research and development environments.

Science.gov (United States)

Prieve, Kurt; Rice, Amanda; Raynor, Peter C

2017-08-01

The aims of this study were to evaluate sound levels produced by compressed air guns in research and development (R&D) environments, replace conventional air gun models with advanced noise-reducing air nozzles, and measure changes in sound levels to assess the effectiveness of the advanced nozzles as engineering controls for noise. Ten different R&D manufacturing areas that used compressed air guns were identified and included in the study. A-weighted sound level and Z-weighted octave band measurements were taken simultaneously using a single instrument. In each area, three sets of measurements, each lasting for 20 sec, were taken 1 m away and perpendicular to the air stream of the conventional air gun while a worker simulated typical air gun work use. Two different advanced noise-reducing air nozzles were then installed. Sound level and octave band data were collected for each of these nozzles using the same methods as for the original air guns. Both of the advanced nozzles provided sound level reductions of about 7 dBA, on average. The highest noise reductions measured were 17.2 dBA for one model and 17.7 dBA for the other. In two areas, the advanced nozzles yielded no sound level reduction, or they produced small increases in sound level. The octave band data showed strong similarities in sound level among all air gun nozzles within the 10-1,000 Hz frequency range. However, the advanced air nozzles generally had lower noise contributions in the 1,000-20,000 Hz range. The observed decreases at these higher frequencies caused the overall sound level reductions that were measured. Installing new advanced noise-reducing air nozzles can provide large sound level reductions in comparison to existing conventional nozzles, which has direct benefit for hearing conservation efforts.

Compressed air piping, 241-SY-101 hydraulic pump retrieval trailer

International Nuclear Information System (INIS)

Wilson, T.R.

1994-01-01

The following Design Analysis was prepared by the Westinghouse Hanford Company to determine pressure losses in the compressed air piping installed on the hydraulic trailer for the 241-SY-101 pump retrieval mission

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.

Carbon Dioxide and Nitrogen Infused Compressed Air Foam for Depopulation of Caged Laying Hens

Science.gov (United States)

Gurung, Shailesh; White, Dima; Archer, Gregory; Styles, Darrel; Zhao, Dan; Farnell, Yuhua; Byrd, James; Farnell, Morgan

2018-01-01

Simple Summary Compressed air, detergent, and water make up compressed air foam. Our laboratory has previously reported that compressed air foam may be an effective method for mass depopulation of caged layer hens. Gases, such as carbon dioxide and nitrogen, have also been used for poultry euthanasia and depopulation. The objective of this study was to produce compressed air foam infused with carbon dioxide or nitrogen to compare its efficacy against foam with air and gas inhalation methods (carbon dioxide or nitrogen) for depopulation of caged laying hens. The study showed that a carbon dioxide-air mixture or 100% nitrogen can replace air to make compressed air foam. However, the foam with carbon dioxide had poor foam quality compared to the foam with air or nitrogen. The physiological stress response of hens subjected to foam treatments with and without gas infusion did not differ significantly. Hens exposed to foam with nitrogen died earlier as compared to methods such as foam with air and carbon dioxide. The authors conclude that infusion of nitrogen into compressed air foam results in better foam quality and shortened time to death as compared to the addition of carbon dioxide. Abstract Depopulation of infected poultry flocks is a key strategy to control and contain reportable diseases. Water-based foam, carbon dioxide inhalation, and ventilation shutdown are depopulation methods available to the poultry industry. Unfortunately, these methods have limited usage in caged layer hen operations. Personnel safety and welfare of birds are equally important factors to consider during emergency depopulation procedures. We have previously reported that compressed air foam (CAF) is an alternative method for depopulation of caged layer hens. We hypothesized that infusion of gases, such as carbon dioxide (CO2) and nitrogen (N2), into the CAF would reduce physiological stress and shorten time to cessation of movement. The study had six treatments, namely a negative control

Compressed Air Energy Storage in Denmark

DEFF Research Database (Denmark)

Salgi, Georges Garabeth; Lund, Henrik

2006-01-01

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......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...

Hydrofluoric acid burn resulting from ignition of gas from a compressed air duster.

Science.gov (United States)

Foster, Kevin N; Jones, LouAnn; Caruso, Daniel M

2003-01-01

A young female suffered burns to her hand after the ignition of gas from a compressed air duster. After debridement and dressing, the patient continued to have pain out of proportion to injury that was refractory to intravenous morphine. The material safety data sheet revealed that the chemical used was 1,1-difluoroethane. High temperatures can cause decompensation to form hydrofluoric acid. Calcium gluconate gel was applied topically to the patient's burns, which caused prompt and complete relief of her pain. A review of different compressed air duster products revealed that the main ingredient in each was a halogenated hydrocarbon. Although not considered flammable, all products have warnings regarding the possibility of ignition under various circumstances. Ignition of the gas in compressed air cleaners not only can cause flame burns, it can also cause chemical damage from exposure to hydrogen and fluoride ions. Prompt recognition and treatment is necessary to prevent severe injury.

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.

Micro-jet Cooling by Compressed Air after MAG Welding

OpenAIRE

Węgrzyn T.; Piwnik J.; Tarasiuk W.; Stanik Z.; Gabrylewski M.

2016-01-01

The material selected for this investigation was low alloy steel weld metal deposit (WMD) after MAG welding with micro-jet cooling. The present investigation was aimed as the following tasks: analyze impact toughness of WMD in terms of micro-jet cooling parameters. Weld metal deposit (WMD) was first time carried out for MAG welding with micro-jet cooling of compressed air and gas mixture of argon and air. Until that moment only argon, helium and nitrogen and its gas mixture were tested for mi...

Exergy analysis of an adiabatic compressed air energy storage system using a cascade of phase change materials

International Nuclear Information System (INIS)

Tessier, Michael J.; Floros, Michael C.; Bouzidi, Laziz; Narine, Suresh S.

2016-01-01

Adiabatic compressed air energy storage is an emerging energy storage technology with excellent power and storage capacities. Currently, efficiencies are approximately 70%, in part due to the issue of heat loss during the compression stage. An exergy analysis is presented on a novel adiabatic compressed air energy storage system design utilizing a cascade of PCMs (phase change materials) for waste heat storage and recovery. The melting temperatures and enthalpies of the PCMs were optimized for this system and were shown to be dependent on the number of PCMs, the number of compression stages, and the maximum compression ratio. Efficiencies of storage and recovery using this approach are predicted to be as high as 85%, a 15% increase over current designs which do not incorporate PCMs. - Highlights: • A compressed air energy storage plant using phase change materials is proposed. • Increasing number of phase change materials increases roundtrip exergy efficiency. • A thermodynamic model allows melting points and latent heats required to be predicted.

Carbon and energy saving markets in compressed air

Science.gov (United States)

Cipollone, R.

2015-08-01

CO2 reduction and fossil fuel saving represent two of the cornerstones of the environmental commitments of all the countries of the world. The first engagement is of a medium to long term type, and unequivocally calls for a new energetic era. The second delays in time the fossil fuel technologies to favour an energetic transition. In order to sustain the two efforts, new immaterial markets have been established in almost all the countries of the world, whose exchanges (purchases and sales) concern CO2 emissions and equivalent fossil fuels that have not been emitted or burned. This paper goes deep inside two aspects not yet exploited: specific CO2 emissions and equivalent fossil fuel burned, as a function of compressed air produced. Reference is made to the current compressor technology, carefully analysing CAGI's (Compressed Air Gas Institute) data and integrating it with the PNUEROP (European Association of manufacturers of compressors, vacuum pumps, pneumatic tools and allied equipment) contribution on the compressor European market. On the base of energy saving estimates that could be put in place, this article also estimates the financial value of the CO2 emissions and fossil fuels avoided.

Evaluation of Two Compressed Air Foam Systems for Culling Caged Layer Hens

Science.gov (United States)

Weiher, Jaclyn A.; Alphin, Robert L.; Hougentogler, Daniel P.

2018-01-01

Simple Summary Control of avian influenza and similar diseases in commercial poultry operations is challenging; the six major steps are surveillance, biosecurity, quarantine, depopulation, disposal, and cleaning and disinfection. Depopulation is used to cull animals that are terminally ill and to reduce the number of animals that can spread an untreatable disease. Water-based foam depopulation was used effectively during the 2014–2015 highly pathogenic avian influenza outbreak in the United States. Water-based foam, however, cannot be used effectively in caged poultry operations. Compressed air foam systems were initially developed for structural fire-fighting and, with modifications, can provide the conditions required to effectively penetrate a poultry cage and provide sufficient residence time for depopulation. In this experiment, compressed air foam was used to depopulate caged layer hens. Compressed air foam resulted in faster unconsciousness than carbon dioxide gassing. The experiment demonstrated that compressed air foam systems have promise for depopulating birds raised in cages. Abstract Outbreaks of avian influenza (AI) and other highly contagious poultry diseases continue to be a concern for those involved in the poultry industry. In the situation of an outbreak, emergency depopulation of the birds involved is necessary. In this project, two compressed air foam systems (CAFS) were evaluated for mass emergency depopulation of layer hens in a manure belt equipped cage system. In both experiments, a randomized block design was used with multiple commercial layer hens treated with one of three randomly selected depopulation methods: CAFS, CAFS with CO2 gas, and CO2 gas. In Experiment 1, a Rowe manufactured CAFS was used, a selection of birds were instrumented, and the time to unconsciousness, brain death, altered terminal cardiac activity and motion cessation were recorded. CAFS with and without CO2 was faster to unconsciousness, however, the other

Micro-jet Cooling by Compressed Air after MAG Welding

Directory of Open Access Journals (Sweden)

Węgrzyn T.

2016-06-01

Full Text Available The material selected for this investigation was low alloy steel weld metal deposit (WMD after MAG welding with micro-jet cooling. The present investigation was aimed as the following tasks: analyze impact toughness of WMD in terms of micro-jet cooling parameters. Weld metal deposit (WMD was first time carried out for MAG welding with micro-jet cooling of compressed air and gas mixture of argon and air. Until that moment only argon, helium and nitrogen and its gas mixture were tested for micro-jet cooling.

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...... of the viscous forces. Using both parameters, a simple model is constructed for the dynamic thermal permeability k', which is completely analogous to the Johnson et al. [J. Fluid Mech. vol. 176, 379 (1987)] model of dynamic viscous permeability k. The resultant modeling of dynamic compressibility provides...... predictions which are closer to the experimental results than the previously used simpler model where the compressibility is the same as in identical circular cross-sectional shaped pores, or distributions of slits, related to a given GAMMA'....

Exergy and exergoeconomic analysis of a Compressed Air Energy Storage combined with a district energy system

International Nuclear Information System (INIS)

Bagdanavicius, Audrius; Jenkins, Nick

2014-01-01

Highlights: • CAES and CAES with thermal storage systems were investigated. • The potential for using heat generated during the compression stage was analysed. • CAES-TS has the potential to be used both as energy storage and heat source. • CAES-TS could be a useful tool for balancing overall energy demand and supply. - Abstract: The potential for using heat generated during the compression stage of a Compressed Air Energy Storage system was investigated using exergy and exergoeconomic analysis. Two Compressed Air Energy Storage systems were analysed: Compressed Air Energy Storage (CAES) and Compressed Air Energy Storage combined with Thermal Storage (CAES-TS) connected to a district heating network. The maximum output of the CAES was 100 MWe and the output of the CAES-TS was 100 MWe and 105 MWth. The study shows that 308 GW h/year of electricity and 466 GW h/year of fuel are used to generate 375 GW h/year of electricity. During the compression of air 289 GW h/year of heat is generated, which is wasted in the CAES and used for district heating in the CAES-TS system. Energy efficiency of the CAES system was around 48% and the efficiency of CAES-TS was 86%. Exergoeconomic analysis shows that the exergy cost of electricity generated in the CAES was 13.89 ¢/kW h, and the exergy cost of electricity generated in the CAES-TS was 11.20 ¢/kW h. The exergy cost of heat was 22.24 ¢/kW h in the CAES-TS system. The study shows that CAES-TS has the potential to be used both as energy storage and heat source and could be a useful tool for balancing overall energy demand and supply

A comparison of sputum induction methods: ultrasonic vs compressed-air nebulizer and hypertonic vs isotonic saline inhalation.

Science.gov (United States)

Loh, L C; Eg, K P; Puspanathan, P; Tang, S P; Yip, K S; Vijayasingham, P; Thayaparan, T; Kumar, S

2004-03-01

Airway inflammation can be demonstrated by the modem method of sputum induction using ultrasonic nebulizer and hypertonic saline. We studied whether compressed-air nebulizer and isotonic saline which are commonly available and cost less, are as effective in inducing sputum in normal adult subjects as the above mentioned tools. Sixteen subjects underwent weekly sputum induction in the following manner: ultrasonic nebulizer (Medix Sonix 2000, Clement Clarke, UK) using hypertonic saline, ultrasonic nebulizer using isotonic saline, compressed-air nebulizer (BestNeb, Taiwan) using hypertonic saline, and compressed-air nebulizer using isotonic saline. Overall, the use of an ultrasonic nebulizer and hypertonic saline yielded significantly higher total sputum cell counts and a higher percentage of cell viability than compressed-air nebulizers and isotonic saline. With the latter, there was a trend towards squamous cell contaminations. The proportion of various sputum cell types was not significantly different between the groups, and the reproducibility in sputum macrophages and neutrophils was high (Intraclass correlation coefficient, r [95%CI]: 0.65 [0.30-0.91] and 0.58 [0.22-0.89], p compressed-air nebulizers and isotonic saline. We conclude that in normal subjects, although both nebulizers and saline types can induce sputum with reproducible cellular profile, ultrasonic nebulizers and hypertonic saline are more effective but less well tolerated.

Light-weight extension tubes for compressed-air garden sprayers

Science.gov (United States)

Thomas W. McConkey; Charles E. Swett

1967-01-01

To hand-spray taller trees safely and efficiently, 8-, 12-, and 16-foot extension tubes for compressed-air garden sprayers were designed and built. These light-weight tubes have been used successfully for spraying white pine leaders for weevil control on the Massabesic Experimental Forest in Maine. Bill of materials and assembly instructions are included.

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

Methods for Sampling and Measurement of Compressed Air Contaminants

International Nuclear Information System (INIS)

Stroem, L.

1976-10-01

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

Trigenerative micro compressed air energy storage: Concept and thermodynamic assessment

International Nuclear Information System (INIS)

Facci, Andrea L.; Sánchez, David; Jannelli, Elio; Ubertini, Stefano

2015-01-01

Highlights: • The trigenerative-CAES concept is introduced. • The thermodynamic feasibility of the trigenerative-CAES is assessed. • The effects of the relevant parameter on the system performances are dissected. • Technological issues on the trigenerative-CAES are highlighted. - Abstract: Energy storage is a cutting edge front for renewable and sustainable energy research. In fact, a massive exploitation of intermittent renewable sources, such as wind and sun, requires the introduction of effective mechanical energy storage systems. In this paper we introduce the concept of a trigenerative energy storage based on a compressed air system. The plant in study is a simplified design of the adiabatic compressed air energy storage and accumulates mechanical and thermal (both hot and cold) energy at the same time. We envisage the possibility to realize a relatively small size trigenerative compressed air energy storage to be placed close to the energy demand, according to the distributed generation paradigm. Here, we describe the plant concept and we identify all the relevant parameters influencing its thermodynamic behavior. Their effects are dissected through an accurate thermodynamic model. The most relevant technological issues, such as the guidelines for a proper choice of the compressor, expander and heat exchangers are also addressed. Our results show that T-CAES may have an interesting potential as a distributed system that combines electricity storage with heat and cooling energy production. We also show that the performances are significantly influenced by some operating and design parameters, whose feasibility in real applications must be considered.

Comparative investigation of thermoelectric air-conditioners versus vapour compression and absorption air-conditioners

International Nuclear Information System (INIS)

Riffat, S.B.; Qiu Guoquan

2004-01-01

This paper compares the performance of three types of domestic air-conditioners, namely the vapour compression air-conditioner (VCAC), the absorption air-conditioner (AAC) and the thermoelectric air-conditioner (TEAC). The basic cycles of the three types of air-conditioning systems are described and methods to calculate their coefficients of performance are presented. General specification data for each type of air-conditioner are given, and performance characteristics are presented. The comparison shows that although VCACs have the advantages of high COP and low purchase price, use of these systems will be phased out due to their contribution to the greenhouse effect and depletion of the ozone layer. AACs are generally bulky, complex and expensive but operate on thermal energy, so their operational consumption is low. TEACs are environmental friendly, simple and reliable but still very expensive at present. Their low COP is an additional factor limiting their application for domestic cooling. TEACs however, have a large potential market as air-conditioners for small enclosures, such as cars and submarine cabins, where the power consumption would be low, or safety and reliability would be important

Gas turbine engine adapted for use in combination with an apparatus for separating a portion of oxygen from compressed air

Science.gov (United States)

Bland, Robert J [Oviedo, FL; Horazak, Dennis A [Orlando, FL

2012-03-06

A gas turbine engine is provided comprising an outer shell, a compressor assembly, at least one combustor assembly, a turbine assembly and duct structure. The outer shell includes a compressor section, a combustor section, an intermediate section and a turbine section. The intermediate section includes at least one first opening and at least one second opening. The compressor assembly is located in the compressor section to define with the compressor section a compressor apparatus to compress air. The at least one combustor assembly is coupled to the combustor section to define with the combustor section a combustor apparatus. The turbine assembly is located in the turbine section to define with the turbine section a turbine apparatus. The duct structure is coupled to the intermediate section to receive at least a portion of the compressed air from the compressor apparatus through the at least one first opening in the intermediate section, pass the compressed air to an apparatus for separating a portion of oxygen from the compressed air to produced vitiated compressed air and return the vitiated compressed air to the intermediate section via the at least one second opening in the intermediate section.

University of Arizona Compressed Air Energy Storage

Energy Technology Data Exchange (ETDEWEB)

Simmons, Joseph [Univ. of Arizona, Tucson, AZ (United States); Muralidharan, Krishna [Univ. of Arizona, Tucson, AZ (United States)

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.

Physics Based Modeling of Compressible Turbulance

Science.gov (United States)

2016-11-07

AFRL-AFOSR-VA-TR-2016-0345 PHYSICS -BASED MODELING OF COMPRESSIBLE TURBULENCE PARVIZ MOIN LELAND STANFORD JUNIOR UNIV CA Final Report 09/13/2016...on the AFOSR project (FA9550-11-1-0111) entitled: Physics based modeling of compressible turbulence. The period of performance was, June 15, 2011...by ANSI Std. Z39.18 Page 1 of 2FORM SF 298 11/10/2016https://livelink.ebs.afrl.af.mil/livelink/llisapi.dll PHYSICS -BASED MODELING OF COMPRESSIBLE

Safety for Compressed Gas and Air Equipment. Module SH-26. Safety and Health.

Science.gov (United States)

Center for Occupational Research and Development, Inc., Waco, TX.

This student module on safety for compressed gas and air equipment is one of 50 modules concerned with job safety and health. This module presents technical data about commonly used gases and stresses the procedures necessary for safe handling of compressed gases. Following the introduction, 14 objectives (each keyed to a page in the text) the…

Bilateral orbital emphysema and pneumocephalus as a result of accidental compressed air exposure.

Science.gov (United States)

Yuksel, Murvet; Yuksel, K Zafer; Ozdemir, Gokhan; Ugur, Tuncay

2007-01-01

Orbital emphysema is a rare condition in the absence of trauma or sinus disease. A 22-year-old man suffering from left orbital trauma due to sudden exposure to compressed air tube was admitted with severe pain in the left eye, swelling, and mild periorbital ecchymosis. Physical examination revealed a large conjunctival laceration in the left orbit. Multislice computed tomographic scanning of the head and orbits showed extensive radiolucencies consistent with the air in both orbits, more prominent in the left. There was also subcutaneous air in the left periorbital soft tissue extending through fronto-temporal and zygomatic areas. Air was also demonstrated adjacent to the left optic canal and within the subarachnoid space intracranially. There was no evidence of any orbital, paranasal sinus, or cranial fracture. Visual acuity was minimally decreased bilaterally. The conjunctiva was sutured under local anesthesia. After 3 weeks of follow-up, the patient completely recovered without visual loss. Bilateral orbital emphysema with pneumocephalus can occur from a high-pressure compressed air injury after unilateral conjunctival trauma without any evidence of fracture.

Microfluidic pressure sensing using trapped air compression.

Science.gov (United States)

Srivastava, Nimisha; Burns, Mark A

2007-05-01

We have developed a microfluidic method for measuring the fluid pressure head experienced at any location inside a microchannel. The principal component is a microfabricated sealed chamber with a single inlet and no exit; the entrance to the single inlet is positioned at the location where pressure is to be measured. The pressure measurement is then based on monitoring the movement of a liquid-air interface as it compresses air trapped inside the microfabricated sealed chamber and calculating the pressure using the ideal gas law. The method has been used to measure the pressure of the air stream and continuous liquid flow inside microfluidic channels (d approximately 50 microm). Further, a pressure drop has also been measured using multiple microfabricated sealed chambers. For air pressure, a resolution of 700 Pa within a full-scale range of 700-100 kPa was obtained. For liquids, pressure drops as low as 70 Pa were obtained in an operating range from 70 Pa to 10 kPa. Since the method primarily uses a microfluidic sealed chamber, it does not require additional fabrication steps and may easily be incorporated in several lab-on-a-chip fluidic applications for laminar as well as turbulent flow conditions.

32 CFR 989.12 - AF Form 813, Request for Environmental Impact Analysis.

Science.gov (United States)

2010-07-01

... 32 National Defense 6 2010-07-01 2010-07-01 false AF Form 813, Request for Environmental Impact... FORCE ENVIRONMENTAL PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.12 AF Form 813, Request for Environmental Impact Analysis. The Air Force uses AF Form 813 to document the need for...

Thermodynamic Analysis of Three Compressed Air Energy Storage Systems: Conventional, Adiabatic, and Hydrogen-Fueled

Directory of Open Access Journals (Sweden)

Hossein Safaei

2017-07-01

Full Text Available We present analyses of three families of compressed air energy storage (CAES systems: conventional CAES, in which the heat released during air compression is not stored and natural gas is combusted to provide heat during discharge; adiabatic CAES, in which the compression heat is stored; and CAES in which the compression heat is used to assist water electrolysis for hydrogen storage. The latter two methods involve no fossil fuel combustion. We modeled both a low-temperature and a high-temperature electrolysis process for hydrogen production. Adiabatic CAES (A-CAES with physical storage of heat is the most efficient option with an exergy efficiency of 69.5% for energy storage. The exergy efficiency of the conventional CAES system is estimated to be 54.3%. Both high-temperature and low-temperature electrolysis CAES systems result in similar exergy efficiencies (35.6% and 34.2%, partly due to low efficiency of the electrolyzer cell. CAES with high-temperature electrolysis has the highest energy storage density (7.9 kWh per m3 of air storage volume, followed by A-CAES (5.2 kWh/m3. Conventional CAES and CAES with low-temperature electrolysis have similar energy densities of 3.1 kWh/m3.

Modeling of Single and Dual Reservoir Porous Media Compressed Gas (Air and CO2) Storage Systems

Science.gov (United States)

Oldenburg, C. M.; Liu, H.; Borgia, A.; Pan, L.

2017-12-01

Intermittent renewable energy sources are causing increasing demand for energy storage. The deep subsurface offers promising opportunities for energy storage because it can safely contain high-pressure gases. Porous media compressed air energy storage (PM-CAES) is one approach, although the only facilities in operation are in caverns (C-CAES) rather than porous media. Just like in C-CAES, PM-CAES operates generally by injecting working gas (air) through well(s) into the reservoir compressing the cushion gas (existing air in the reservoir). During energy recovery, high-pressure air from the reservoir is mixed with fuel in a combustion turbine to produce electricity, thereby reducing compression costs. Unlike in C-CAES, 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. Because air is the working gas, PM-CAES has fairly low thermal efficiency and low energy storage density. To improve the energy storage density, we have conceived and modeled a closed-loop two-reservoir compressed CO2 energy storage system. One reservoir is the low-pressure reservoir, and the other is the high-pressure reservoir. CO2 is cycled back and forth between reservoirs depending on whether energy needs to be stored or recovered. We have carried out thermodynamic and parametric analyses of the performance of an idealized two-reservoir CO2 energy storage system under supercritical and transcritical conditions for CO2 using a steady-state model. Results show that the transcritical compressed CO2 energy storage system has higher round-trip efficiency and exergy efficiency, and larger energy storage density than the supercritical compressed CO2 energy storage. However, the configuration of supercritical compressed CO2 energy storage is simpler, and the energy storage densities of the two systems are both higher than that of PM-CAES, which is advantageous in terms of storage volume for a given

[Pediatric orbital emphysema caused by a compressed-air pistol shot: a case report].

Science.gov (United States)

Navarro-Mingorance, A; Reyes-Dominguez, S B; León-León, M C

2014-09-01

We report the case of a 2 year-old child with orbital emphysema secondary to a compressed-air gun shot in the malar region, with no evidence of orbital wall fracture. Conservative treatment was applied, and no complications were observed. Orbital emphysema in the absence of an orbital wall fracture is a rare situation. Orbital emphysema is usually seen in facial trauma associated with damage to the adjacent paranasal sinuses or facial bones. To our knowledge there have been very few reports of orbital emphysema caused by a compressed-air injury. Copyright © 2012 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

Optimal design of compressed air energy storage systems

Energy Technology Data Exchange (ETDEWEB)

Ahrens, F. W.; Sharma, A.; Ragsdell, K. M.

1979-01-01

Compressed air energy storage (CAES) power systems are currently being considered by various electric utilities for load-leveling applications. Models of CAES systems which employ natural underground aquifer formations, and present an optimal design methodology which demonstrates their economic viability are developed. This approach is based upon a decomposition of the CAES plant and utility grid system into three partially-decoupled subsystems. Numerical results are given for a plant employing the Media, Illinois Galesville aquifer formation.

CLASSIFICATION OF THE MGR SITE COMPRESSED AIR SYSTEM

International Nuclear Information System (INIS)

J.A. Ziegler

1999-01-01

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) site compressed air system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998)

Study on the influence of supplying compressed air channels and evicting channels on pneumatical oscillation systems for vibromooshing

Science.gov (United States)

Glăvan, D. O.; Radu, I.; Babanatsas, T.; Babanatis Merce, R. M.; Kiss, I.; Gaspar, M. C.

2018-01-01

The paper presents a pneumatic system with two oscillating masses. The system is composed of a cylinder (framework) with mass m1, which has a piston with mass m2 inside. The cylinder (framework system) has one supplying channel for compressed air and one evicting channel for each work chamber (left and right of the piston). Functionality of the piston position comparatively with the cylinder (framework) is possible through the supplying or evicting of compressed air. The variable force that keeps the movement depends on variation of the pressure that is changing depending on the piston position according to the cylinder (framework) and to the section form that is supplying and evicting channels with compressed air. The paper presents the physical model/pattern, the mathematical model/pattern (differential equations) and numerical solution of the differential equations in hypothesis with the section form of supplying and evicting channels with compressed air is rectangular (variation linear) or circular (variation nonlinear).

Porous media experience applicable to field evaluation for compressed air energy storage

Energy Technology Data Exchange (ETDEWEB)

Allen, R.D.; Gutknecht, P.J.

1980-06-01

A survey is presented of porous media field experience that may aid in the development of a compressed air energy storage field demonstration. Work done at PNL and experience of other groups and related industries is reviewed. An overall view of porous media experience in the underground storage of fluids is presented. CAES experience consists of site evaluation and selection processes used by groups in California, Kansas, and Indiana. Reservoir design and field evaluation of example sites are reported. The studies raised questions about compatibility with depleted oil and gas reservoirs, storage space rights, and compressed air regulations. Related experience embraces technologies of natural gas, thermal energy, and geothermal and hydrogen storage. Natural gas storage technology lends the most toward compressed air storage development, keeping in mind the respective differences between stored fluids, physical conditions, and cycling frequencies. Both fluids are injected under pressure into an aquifer to form a storage bubble confined between a suitable caprock structure and partially displaced ground water. State-of-the-art information is summarized as the necessary foundation material for field planning. Preliminary design criteria are given as recommendations for basic reservoir characteristics. These include geometric dimensions and storage matrix properties such as permeability. Suggested ranges are given for injection air temperature and reservoir pressure. The second step in developmental research is numerical modeling. Results have aided preliminary design by analyzing injection effects upon reservoir pressure, temperature and humidity profiles. Results are reported from laboratory experiments on candidate sandstones and caprocks. Conclusions are drawn, but further verification must be done in the field.

Commissioning and operating experience of compressed air system of a reprocessing plant (Paper No. 5.10)

International Nuclear Information System (INIS)

Nair, M.K.T.; Bajpai, D.D.; Mishra, A.K.; Kulkarni, H.B.; Raje, R.V.; Rajeshwar, S.

1992-01-01

Compressed air system is one of the most important utility systems, required in the continued operation of a radiochemical plant. Moisture and oil free compressed air is used in large scale for process control and process operations in reprocessing plants. Commissioning and operating experience of this system is described in detail, to indicate the importance of the system in the overall design and operation of such chemical plant. (author). 1 tab

Study, Evaluation and Implementation of Improvement in a Compressed Air Plant

Directory of Open Access Journals (Sweden)

Carlos Roberto Altafini

2013-12-01

Full Text Available This paper presents a study of a compressed air generation system in a bus manufacturer, being evaluated the operation of the compressors to identify the electric energy consumption. A maintenance plan is elaborated to correct the air system leaks and also proposes the reuse of thermal energy generated by the compressors. Initially, as for the purpose of this paper, a revision of fundamentals related to thermodynamics transformation is presented. Afterwards, some important electric energy concepts will lead to the understanding of the energy consumption of the compressors. Then, an overview about compressed air generation systems will be showed with the goal of understanding techniques of energetic efficiency. The tools used in this study for collecting data were the software of a compressor manufacturer with pressure transducers and an energy analyzer. The basic concepts and their uses will be shown along this paper. The proposal of electric energy consumption reduction was achieved with the installation of compressor operation managers and yields a reduction about 60,600 kWh per month, which provided a monthly saving of R$19,400.00, validating the collected data. For heat recovery from the cooling air compressors, externally finned coils were sized to heat water up to 55◦C and used in a process of heating rubber gaskets. For air leakage reduction, a working methodology to perform the corrective and preventive maintenance has been prepared, and a control system in the form of internal audit. The obtained air leakage reduction was about 50%.

Experimental investigations on performance of liquid desiccant-vapor compression hybrid air conditioner

International Nuclear Information System (INIS)

Mohan, B. Shaji; Tiwari, Shaligram; Maiya, M.P.

2015-01-01

A coupled desiccant column is integrated with a conventional room air conditioner (AC) to enhance dehumidification of the room air. One desiccant column (absorber) is placed after the evaporator the other (regenerator) after the condenser of the AC unit. Such a novel liquid desiccant vapour compression hybrid air conditioning system has been fabricated and tested in a balanced ambient room type calorimeter for very low flow rates of liquid desiccant (lithium bromide solution). The moisture from the cold supply air is transferred to the hot condenser air by the desiccant flowing in the loop, thereby complimenting the dehumidification of the room air at the evaporator. The supply air is also sensibly heated during the dehumidification process by liquid desiccant in the absorber, which together enables the hybrid system to maintain low humidity in the room. Whereas the liquid desiccant is regenerated by the condenser waste heat, the entire cooling is derived only by the AC unit. The experimental results show that an increase of room temperature reduces both dehumidification of process air and regeneration of liquid desiccant, whereas an increase of room specific humidity enhances both these for the flow rate of the liquid desiccant in the range of 0.2–1.6% of the air flow rate through the absorber. - Highlights: • A liquid desiccant vapor compression hybrid system is fabricated and tested. • The liquid desiccant reduces latent load but equally increases sensible load. • Hybrid system performance is studied for varying room temperature and humidity. • Higher room temperature lowers air dehumidification and desiccant regeneration. • Increase of room specific humidity enhances dehumidification and also regeneration

76 FR 13661 - In the Matter of Certain Connecting Devices (“Quick Clamps”) for Use With Modular Compressed Air...

Science.gov (United States)

2011-03-14

... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-587] In the Matter of Certain Connecting Devices (``Quick Clamps'') for Use With Modular Compressed Air Conditioning Units, Including Filters... within the United States after importation of certain devices for modular compressed air conditioning...

AF family shares experience with child's autism > U.S. Air Force >

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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.

Unintended inhalation of nitric oxide by contamination of compressed air: physiologic effects and interference with intended nitric oxide inhalation in acute lung injury.

Science.gov (United States)

Benzing, A; Loop, T; Mols, G; Geiger, K

1999-10-01

Compressed air from a hospital's central gas supply may contain nitric oxide as a result of air pollution. Inhaled nitric oxide may increase arterial oxygen tension and decrease pulmonary vascular resistance in patients with acute lung injury and acute respiratory distress syndrome. Therefore, the authors wanted to determine whether unintentional nitric oxide inhalation by contamination of compressed air influences arterial oxygen tension and pulmonary vascular resistance and interferes with the therapeutic use of nitric oxide. Nitric oxide concentrations in the compressed air of a university hospital were measured continuously by chemiluminescence during two periods (4 and 2 weeks). The effects of unintended nitric oxide inhalation on arterial oxygen tension (n = 15) and on pulmonary vascular resistance (n = 9) were measured in patients with acute lung injury and acute respiratory distress syndrome by changing the source of compressed air of the ventilator from the hospital's central gas supply to a nitric oxide-free gas tank containing compressed air. In five of these patients, the effects of an additional inhalation of 5 ppm nitric oxide were evaluated. During working days, compressed air of the hospital's central gas supply contained clinically effective nitric oxide concentrations (> 80 parts per billion) during 40% of the time. Change to gas tank-supplied nitric oxide-free compressed air decreased the arterial oxygen tension by 10% and increased pulmonary vascular resistance by 13%. The addition of 5 ppm nitric oxide had a minimal effect on arterial oxygen tension and pulmonary vascular resistance when added to hospital-supplied compressed air but improved both when added to tank-supplied compressed air. Unintended inhalation of nitric oxide increases arterial oxygen tension and decreases pulmonary vascular resistance in patients with acute lung injury and acute respiratory distress syndrome. The unintended nitric oxide inhalation interferes with the

The effect of compressed air massage on skin blood flow and temperature.

Science.gov (United States)

Mars, Maurice; Maharaj, Sunil S; Tufts, Mark

2005-01-01

Compressed air massage is a new treatment modality that uses air under pressure to massage skin and muscle. It is claimed to improve skin blood flow but this has not been verified. Several pilot studies were undertaken to determine the effects of compressed air massage on skin blood flow and temperature. Skin blood flow (SBF), measured using laser Doppler fluxmetry and skin temperature was recorded under several different situations: (i) treatment, at 1 Bar pressure using a single-hole (5-mm) applicator head, for 1 min at each of several sites on the right and left lower legs, with SBF measured on the dorsum of the left foot; (ii) at the same treatment pressure, SBF was measured over the left tibialis anterior when treatment was performed at different distances from the probe; (iii) SBF and skin temperature of the lower leg were measured with treatment at 0 or 1 Bar for 45 min, using two different applicator heads; (iv) SBF was measured on the dorsum of the foot of 10 subjects with treatment for 1 min at 0, 0.5, 1, 1.5 and 2 Bar using three different applicator heads. (i) SBF of the left foot was not altered by treatment of the right leg or chest, but was significantly increased during treatment of the left sole and first web, p Compressed air massage causes an immediate increase in SBF, and an immediate fall in SBF when treatment is stopped. The effect appears to be locally and not centrally mediated and is related to the pressure used. Treatment cools the skin for at least 15 min after a 45-min treatment.

Evaluation of thermal energy storage materials for advanced compressed air energy storage systems

Energy Technology Data Exchange (ETDEWEB)

Zaloudek, F.R.; Wheeler, K.R.; Marksberry, L.

1983-03-01

Advanced Compressed-Air Energy Storage (ACAS) plants have the near-term potential to reduce the fuel consumption of compressed-air plants from 33 to 100%, depending upon their design. Fuel is saved by storing some or all of the heat of compression as sensible heat which is subsequently used to reheat the compressed air prior to expansion in the turbine generator. The thermal storage media required for this application must be low cost and durable. The objective of this project was to screen thermal store materials based on their thermal cycle durability, particulate formation and corrosion resistant characteristics. The materials investigated were iron oxide pellets, Denstone pebbles, cast-iron balls, and Dresser basalt rock. The study specifically addressed the problems of particle formation and thermal ratcheting of the materials during thermal cycling and the chemical attack on the materials by the high temperature and moist environment in an ACAS heat storage bed. The results indicate that from the durability standpoint Denstone, cast iron containing 27% or more chromium, and crushed Dresser basalt would possibly stand up to ACAS conditions. If costs are considered in addition to durability and performance, the crushed Dresser basalt would probably be the most desirable heat storage material for adiabatic and hybrid ACAS plants, and more in-depth longer term thermal cycling and materials testing of Dresser basalt is recommended. Also recommended is the redesign and costing analysis of both the hybrid and adiabatic ACAS facilities based upon the use of Dresser basalt as the thermal store material.

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.

[Bone and joint changes due to compressed air in divers and Caisson workers (author's transl)].

Science.gov (United States)

Poser, H; Gabriel-Jürgens, P

1977-02-01

The radiological and morphological changes of Caisson disease in the skeleton are well known. The findings of interest to radiologists are described. Because of its position, its was possible to review a large number of divers in Kiel; these have been under observation for years, and even decades. The development, manifestation and course of chronic skeletal changes due to compressed air are described to compressed air are described and, according to severity, are classified into types 1 to 4. Late changes are discussed in detail, since these are of importance in relation to compensation.

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...

Pneumatic hybridization of a diesel engine using compressed air storage for wind-diesel energy generation

International Nuclear Information System (INIS)

Basbous, Tammam; Younes, Rafic; Ilinca, Adrian; Perron, Jean

2012-01-01

In this paper, we are studying an innovative solution to reduce fuel consumption and production cost for electricity production by Diesel generators. The solution is particularly suitable for remote areas where the cost of energy is very high not only because of inherent cost of technology but also due to transportation costs. It has significant environmental benefits as the use of fossil fuels for electricity generation is a significant source of GHG (Greenhouse Gas) emissions. The use of hybrid systems that combine renewable sources, especially wind, and Diesel generators, reduces fuel consumption and operation cost and has environmental benefits. Adding a storage element to the hybrid system increases the penetration level of the renewable sources, that is the percentage of renewable energy in the overall production, and further improves fuel savings. In a previous work, we demonstrated that CAES (Compressed Air Energy Storage) has numerous advantages for hybrid wind-diesel systems due to its low cost, high power density and reliability. The pneumatic hybridization of the Diesel engine consists to introduce the CAES through the admission valve. We have proven that we can improve the combustion efficiency and therefore the fuel consumption by optimizing Air/Fuel ratio thanks to the CAES assistance. As a continuation of these previous analyses, we studied the effect of the intake pressure and temperature and the exhaust pressure on the thermodynamic cycle of the diesel engine and determined the values of these parameters that will optimize fuel consumption. -- Highlights: ► Fuel economy analysis of a simple pneumatic hybridization of the Diesel engine using stored compressed air. ► Thermodynamic analysis of the pneumatic hybridization of diesel engines for hybrid wind-diesel energy systems. ► Analysis of intake pressure and temperature of compressed air and exhaust pressure on pressure/temperature during Diesel thermodynamic cycle. ► Direct admission of

Operability Test Report for 241-T compressed air system and heat pump

International Nuclear Information System (INIS)

Freeman, R.D.

1995-02-01

This Operability Test Report (OTR) documents the results of functional testing performed on the operating parameters of the 241-T-701 Compressed Air System. The System was successfully installed and tested per work package 2W-92-01172

Preliminary Investigation of an Underwater Ramjet Powered by Compressed Air

Science.gov (United States)

Mottard, Elmo J.; Shoemaker, Charles J.

1961-01-01

Part I contains the results of a preliminary experimental investigation of a particular design of an underwater ramjet or hydroduct powered by compressed air. The hydroduct is a propulsion device in which the energy of an expanding gas imparts additional momentum to a stream of water through mixing. The hydroduct model had a fineness ratio of 5.9, a maximum diameter of 3.2 inches, and a ratio of inlet area to frontal area of 0.32. The model was towed at a depth of 1 inch at forward speeds between 20 and 60 feet per second for airflow rates from 0.1 to 0.3 pound per second. Longitudinal force and pressures at the inlet and in the mixing chamber were determined. The hydroduct produced a positive thrust-minus-drag force at every test speed. The force and pressure coefficients were functions primarily of the ratio of weight airflow to free-stream velocity. The maximum propulsive efficiency based on the net internal thrust and an isothermal expansion of the air was approximately 53 percent at a thrust coefficient of 0.10. The performance of the test model may have been influenced by choking of the exit flow. Part II is a theoretical development of an underwater ramjet using air as "fuel." The basic assumption of the theoretical analysis is that a mixture of water and air can be treated as a compressible gas. More information on the properties of air-water mixtures is required to confirm this assumption or to suggest another approach. A method is suggested from which a more complete theoretical development, with the effects of choking included, may be obtained. An exploratory computation, in which this suggested method was used, indicated that the effect of choked flow on the thrust coefficient was minor.

Corrosion of well casings in compressed air energy storage environments

Energy Technology Data Exchange (ETDEWEB)

Elmore, R.P.; Stottlemyre, J.A.

1980-10-01

The goal of this study was to determine corrosive effects of compressed air energy storage (CAES) environments on several well casing materials to aid in material selections. A literature search on corrosion behavior of well casing material in similar environments revealed that corrosion rates of 0.20 to 0.25 mm/y might be expected. This information was employed in designing the laboratory study. Unstressed electrically isolate samples of various carbon steels were autoclaved at varying humidities, temperatures, and exposure durations to simulate anticipated environments in the well bore during CAES operation. All compressed air tests were run at 12.1 MPa. Temperatures varied from 323/sup 0/K to 573/sup 0/K, and humidity varied from 100% to completely dry air. The effects of salts in the humidified air were also studied. Results indicated that typical well casings of carbon steel as used in oil, gas, and water production wells adequately withstand the anticipated CAES reservoir environment. An acceptable corrosion rate arrived at by these laboratory simulations was between 0.0015 and 0.15 mm/y. Corrosion was caused by metal oxidation that formed a protective scale of iron oxide. Higher temperatures, humidity rates, or salinity content of the humid air increased corrosion. Corrosion also increased on a metal coupon in contact with a sandstone sample, possibly due to crevice corrosion. For each of these factors either singularly or collectively, the increased corrosion rates were still acceptable with the maximum measured at 0.15 mm/y. When coupons were reused in an identical test, the corrosion rates increased beyond the anticipated values that had been determined by extrapolation from one-time runs. Fine cracking of the protective scale probably occurred due to thermal variations, resulting in increased corrosion rates and a greater potential for particulates, which could plug the reservoir.

Thermodynamic characteristics of a novel supercritical compressed air energy storage system

International Nuclear Information System (INIS)

Guo, Huan; Xu, Yujie; Chen, Haisheng; Zhou, Xuezhi

2016-01-01

Highlights: • A novel supercritical compressed air energy storage system is proposed. • The energy density of SC-CAES is approximately 18 times larger than that of conventional CAES. • The characteristic of thermodynamics and exergy destruction is comprehensively analysed. • The corresponding optimum relationship between charging and discharging pressure is illustrated. • A turning point of efficiency is indicated because of the heat transfer of crossing the critical point. - Abstract: A novel supercritical compressed air energy storage (SC-CAES) system is proposed by our team to solve the problems of conventional CAES. The system eliminates the dependence on fossil fuel and large gas-storage cavern, as well as possesses the advantages of high efficiency by employing the special properties of supercritical air, which is significant for the development of electrical energy storage. The thermodynamic model of the SC-CAES system is built, and the thermodynamic characters are revealed. Through the exergy analysis of the system, the processes of the larger exergy destruction include compression, expansion, cold storage/heat exchange and throttle. Furthermore, sensitivity analysis shows that there is an optimal energy releasing pressure to make the system achieve the highest efficiency when energy storage pressure is constant. The efficiency of SC-CAES is expected to reach about 67.41% when energy storage pressure and energy releasing pressure are 120 bar and 95.01 bar, respectively. At the same time, the energy density is 18 times larger than that of conventional CAES. Sensitivity analysis also shows the change laws of system efficiency varying with other basic system parameters. The study provides support for the design and engineering of SC-CAES.

Modeling of coupled thermodynamic and geomechanical performance of underground compressed air energy storage in lined rock caverns

Energy Technology Data Exchange (ETDEWEB)

Rutqvist, Jonny; Kim, Hyung-Mok; Ryu, Dong-Woo; Synn, Joong-Ho; Song, Won-Kyong

2012-06-01

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

Multi-objective optimization and exergoeconomic analysis of a combined cooling, heating and power based compressed air energy storage system

International Nuclear Information System (INIS)

Yao, Erren; Wang, Huanran; Wang, Ligang; Xi, Guang; Maréchal, François

2017-01-01

Highlights: • A novel tri-generation based compressed air energy storage system. • Trade-off between efficiency and cost to highlight the best compromise solution. • Components with largest irreversibility and potential improvements highlighted. - Abstract: Compressed air energy storage technologies can improve the supply capacity and stability of the electricity grid, particularly when fluctuating renewable energies are massively connected. While incorporating the combined cooling, heating and power systems into compressed air energy storage could achieve stable operation as well as efficient energy utilization. In this paper, a novel combined cooling, heating and power based compressed air energy storage system is proposed. The system combines a gas engine, supplemental heat exchangers and an ammonia-water absorption refrigeration system. The design trade-off between the thermodynamic and economic objectives, i.e., the overall exergy efficiency and the total specific cost of product, is investigated by an evolutionary multi-objective algorithm for the proposed combined system. It is found that, with an increase in the exergy efficiency, the total product unit cost is less affected in the beginning, while rises substantially afterwards. The best trade-off solution is selected with an overall exergy efficiency of 53.04% and a total product unit cost of 20.54 cent/kWh, respectively. The variation of decision variables with the exergy efficiency indicates that the compressor, turbine and heat exchanger preheating the inlet air of turbine are the key equipment to cost-effectively pursuit a higher exergy efficiency. It is also revealed by an exergoeconomic analysis that, for the best trade-off solution, the investment costs of the compressor and the two heat exchangers recovering compression heat and heating up compressed air for expansion should be reduced (particularly the latter), while the thermodynamic performance of the gas engine need to be improved

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.

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.

Improved fireman's compressed air breathing system pressure vessel development program

Science.gov (United States)

King, H. A.; Morris, E. E.

1973-01-01

Prototype high pressure glass filament-wound, aluminum-lined pressurant vessels suitable for use in a fireman's compressed air breathing system were designed, fabricated, and acceptance tested in order to demonstrate the feasibility of producing such high performance, lightweight units. The 4000 psi tanks have a 60 standard cubic foot (SCF) air capacity, and have a 6.5 inch diamter, 19 inch length, 415 inch volume, weigh 13 pounds when empty, and contain 33 percent more air than the current 45 SCF (2250 psi) steel units. The current steel 60 SCF (3000 psi) tanks weigh approximately twice as much as the prototype when empty, and are 2 inches, or 10 percent shorter. The prototype units also have non-rusting aluminum interiors, which removes the hazard of corrosion, the need for internal coatings, and the possibility of rust particles clogging the breathing system.

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

International Nuclear Information System (INIS)

Kim, Hyung-Mok; Rutqvist, Jonny; Ryu, Dong-Woo; Choi, Byung-Hee; Sunwoo, Choon; Song, Won-Kyong

2012-01-01

Highlights: ► We carried out coupled thermodynamic, multiphase fluid flow and heat transport analysis. ► Coupled behavior associated with underground lined caverns for CAES was investigated. ► Air leakage could be reduced by controlling the permeability of concrete lining. ► Heat loss during compression would be gained back at subsequent decompression phase. -- Abstract: 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 operation 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 −18 m 2 would result in an acceptable air leakage rate of less than 1%, with the operation 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 operation air pressure and when the lining is kept at relatively high moisture content. 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 of less than 1 × 10 −18 m 2 , heat loss by heat conduction tends to become proportionally more important. However, the energy loss by heat conduction can be

Waste Feed Delivery Raw Water and Potable Water and Compressed Air Capacity Evaluation

International Nuclear Information System (INIS)

MAY, T.H.

2000-01-01

This study evaluated the ability of the Raw Water, Potable Water, and Compressed Air systems to support safe storage as well as the first phase of the Waste Feed Delivery. Several recommendations are made to improve the system

Improving the performance of a compression ignition engine by directing flow of inlet air

Science.gov (United States)

Kemper, Carlton

1946-01-01

The object of this report is to present the results of tests performed by the National Advisory Committee for Aeronautics to determine the effect on engine performance of directing the flow of the inlet air to a 5-inch by 7-inch cylinder, solid injection, compression ignition engine, After a few preliminary tests, comparative runs were made at a speed of 1500 r.p.m. with and without directed air flow. It was found that directing the flow of the inlet air toward the fuel injection valve gave steadier engine operation, and an appreciable increase in power, and decreased fuel consumption. The results indicate the possibility of improving the performance of a given type of combustion chamber without changing its shape and with no change in valve timing. They would also seem to prove that directional turbulence, set up before the inlet valve of a four-stroke cycle engine, continues in the engine cylinder throughout the compression stroke.

Depopulation of Caged Layer Hens with a Compressed Air Foam System

Science.gov (United States)

Gurung, Shailesh; Hoffman, John; Stringfellow, Kendre; Abi-Ghanem, Daad; Zhao, Dan; Caldwell, David; Lee, Jason; Styles, Darrel; Berghman, Luc; Byrd, James; Farnell, Yuhua; Archer, Gregory

2018-01-01

Simple Summary Reportable diseases, such as avian influenza, spread rapidly among poultry, resulting in the death of a large number of birds. Once such a disease has been diagnosed at a farm, infected and susceptible birds are rapidly killed to prevent the spread of the disease. The methods to eliminate infected caged laying hens are limited. An experiment was conducted to study the effectiveness of foam made from compressed air, water, and soap to kill laying hens in cages. The study found that stress levels of the hens killed using compressed air foam in cages to be similar to the hens killed by carbon dioxide or the negative control. Hens exposed to carbon dioxide died earlier as compared to the foam methods. The authors conclude that application of compressed air foam in cages is an alternative to methods such as gas inhalation and ventilation shutdown to rapidly and humanely kill laying hens during epidemics. Abstract During the 2014–2015 US highly pathogenic avian influenza (HPAI) outbreak, 50.4 million commercial layers and turkeys were affected, resulting in economic losses of $3.3 billion. Rapid depopulation of infected poultry is vital to contain and eradicate reportable diseases like HPAI. The hypothesis of the experiment was that a compressed air foam (CAF) system may be used as an alternative to carbon dioxide (CO2) inhalation for depopulating caged layer hens. The objective of this study was to evaluate corticosterone (CORT) and time to cessation of movement (COM) of hens subjected to CAF, CO2 inhalation, and negative control (NEG) treatments. In Experiment 1, two independent trials were conducted using young and spent hens. Experiment 1 consisted of five treatments: NEG, CO2 added to a chamber, a CO2 pre-charged chamber, CAF in cages, and CAF in a chamber. In Experiment 2, only spent hens were randomly assigned to three treatments: CAF in cages, CO2 added to a chamber, and aspirated foam. Serum CORT levels of young hens were not significantly

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)

Adiabatic Compression Sensitivity of AF-M315E

Science.gov (United States)

2015-07-01

Brand for their technical expertise and guidance. He also wishes to thank Mr. Stephen McKim from NASA Goddard Space Flight Center for his assistance...Wilson, D. B., and Stoltzfus, J. M. "Adiabatic Compression of Oxygen: Real Fluid Temperatures," 2000. 10Ismail, I. M. K., and Hawkins , T. W. "Adiabatic

Energy Efficiency Analysis of Discharge Modes of an Adiabatic Compressed Air Energy Storage System

OpenAIRE

Shane D. Inder; Mehrdad Khamooshi

2017-01-01

Efficient energy storage is a crucial factor in facilitating the uptake of renewable energy resources. Among the many options available for energy storage systems required to balance imbalanced supply and demand cycles, compressed air energy storage (CAES) is a proven technology in grid-scale applications. This paper reviews the current state of micro scale CAES technology and describes a micro-scale advanced adiabatic CAES (A-CAES) system, where heat generated during compression is stored fo...

Single-Site Active Iron-Based Bifunctional Oxygen Catalyst for a Compressible and Rechargeable Zinc-Air Battery.

Science.gov (United States)

Ma, Longtao; Chen, Shengmei; Pei, Zengxia; Huang, Yan; Liang, Guojin; Mo, Funian; Yang, Qi; Su, Jun; Gao, Yihua; Zapien, Juan Antonio; Zhi, Chunyi

2018-02-27

The exploitation of a high-efficient, low-cost, and stable non-noble-metal-based catalyst with oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) simultaneously, as air electrode material for a rechargeable zinc-air battery is significantly crucial. Meanwhile, the compressible flexibility of a battery is the prerequisite of wearable or/and portable electronics. Herein, we present a strategy via single-site dispersion of an Fe-N x species on a two-dimensional (2D) highly graphitic porous nitrogen-doped carbon layer to implement superior catalytic activity toward ORR/OER (with a half-wave potential of 0.86 V for ORR and an overpotential of 390 mV at 10 mA·cm -2 for OER) in an alkaline medium. Furthermore, an elastic polyacrylamide hydrogel based electrolyte with the capability to retain great elasticity even under a highly corrosive alkaline environment is utilized to develop a solid-state compressible and rechargeable zinc-air battery. The creatively developed battery has a low charge-discharge voltage gap (0.78 V at 5 mA·cm -2 ) and large power density (118 mW·cm -2 ). It could be compressed up to 54% strain and bent up to 90° without charge/discharge performance and output power degradation. Our results reveal that single-site dispersion of catalytic active sites on a porous support for a bifunctional oxygen catalyst as cathode integrating a specially designed elastic electrolyte is a feasible strategy for fabricating efficient compressible and rechargeable zinc-air batteries, which could enlighten the design and development of other functional electronic devices.

Simulation and analysis of different adiabatic Compressed Air Energy Storage plant configurations

International Nuclear Information System (INIS)

Hartmann, Niklas; Vöhringer, O.; Kruck, C.; Eltrop, L.

2012-01-01

Highlights: ► We modeled several configurations of an adiabatic Compressed Air Energy Storage (CAES) plant. ► We analyzed changes in efficiency of these configurations under varying operating conditions. ► The efficiency of the adiabatic CAES plant can reach about 70% for the isentropic configuration. ► In the polytropic case, the efficiency is about 10% lower (at about 60%) than in the isentropic configuration. ► The efficiency is highest for a two-stage CAES configuration and highly dependent on the cooling and heating demand. - Abstract: In this paper, the efficiency of one full charging and discharging cycle of several adiabatic Compressed Air Energy Storage (CAES) configurations are analyzed with the help of an energy balance. In the second step main driving factors for the efficiency of the CAES configurations are examined with the help of sensitivity analysis. The results show that the efficiency of the polytropic configuration is about 60%, which is considerable lower than literature values of an adiabatic CAES of about 70%. The high value of 70% is only reached for the isentropic (ideal) configuration. Key element to improve the efficiency is to develop high temperature thermal storages (>600 °C) and temperature resistant materials for compressors. The highest efficiency is delivered by the two-stage adiabatic CAES configuration. In this case the efficiency varies between 52% and 62%, depending on the cooling and heating demand. If the cooling is achieved by natural sources (such as a river), a realistic estimation of the efficiency of adiabatic Compressed Air Energy Storages (without any greenhouse gas emissions due to fuel consumption) is about 60%.

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....

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

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.

Researches on the CAES (Compressed Air Energy Storage) system

Energy Technology Data Exchange (ETDEWEB)

Shin Hee Soon; Kang, Sang Soo; Kwon, Kwang Soo [Korea Institute of Geology Mining and Materials, Taejon (Korea)] [and others

1998-12-01

CAES which is called as a compressed air energy storage was firstly developed at Huntorf, German in 1978. The capacity of that system was 290 MW, and it can be treated as a first commercial power plant. CAES has a lot of merits, such as saving the unit price of power generation, averaging the peak demand, improvement of maintenance, enlarging the benefit of dynamic use. According to the literature survey, the unlined rock cavern should be proposed to be a reasonable storing style as a method of compressed air storage in Korea. In this study, the most important techniques were evaluated through the investigation of the foreign construction case studies, especially on the unlined rock caverns in hard rock mass. We decided the hill of the Korea Institute of Geology, Mining and materials as CAES site. If we construct the underground spaces in this site, the demand for electricity nearby Taejon should be considered. So we could determine the capacity of the power plant as a 350 MW. This capacity needs a underground space of 200,000 m{sup 3}, and we can conclude 4 parallel tunnels through the numerical studies. Design parameters were achieved from 300 m depth boring job and image processing job. Moreover the techniques for determination of joint characteristics from the images could be obtained. Blasting pattern was designed on the underground spaces, and automatic gas control system and thermomechanical characteristics on caverns were also studied. (author). 51 refs., 79 tabs., 114 figs.

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)

Subcooled compressed air energy storage system for coproduction of heat, cooling and electricity

NARCIS (Netherlands)

Arabkoohsar, A.; Dremark-Larsen, M.; Lorentzen, R.; Andresen, G. B.

2017-01-01

Various configurations of compressed air energy storage technology have received attention over the last years due to the advantages that this technology offers relative to other power storage technologies. This work proposes a new configuration of this technology aiming at cogeneration of

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.

Operation of the PAVE PAWS Radar System at Beale Air Force Base, California. Part 2. Public Comment & AF Response.

Science.gov (United States)

1980-07-01

Kentwood Moblie Homes 2635 Esplanade Chico, CA. 95926 Boeger Br~thers Helena Chemical Co. P.O. Box 367 1630 E. Shaw Ave.-STE. 130 Grioley, CA. 95948...DEIS action for pacemaker owners is not sufficient. The 07 AF should advertise the existence of the problem in the local newspapers. and replace old...does not believe that there is a problem to be advertised . Neither does the Air Force suggest that any present pacemaker owners be subjected to the

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...

Thermodynamic analysis of a novel tri-generation system based on compressed air energy storage and pneumatic motor

International Nuclear Information System (INIS)

Liu, Jin-Long; Wang, Jian-Hua

2015-01-01

Based on CAES (compressed air energy storage) and PM (pneumatic motor), a novel tri-generation system (heat energy, mechanical energy and cooling power) is proposed in this paper. Both the cheap electricity generated at night and the excess power from undelivered renewable energy due to instability, can be stored as compressed air and hot water by the proposed system. When energy is in great demand, the compressed air stored in this system is released to drive PM to generate mechanical power. The discharged air from PM can be further utilized as valuable cooling power. Compared to conventional CAES systems, the biggest characteristic of the proposed system is that the discharged air usually abandoned is used as cooling power. In order to study the performances of this system, a thermodynamic analysis and an experimental investigation are carried out. The thermodynamic model is validated by the experimental data. Using the validated thermodynamic model, the mechanical energy output, cooling capacity and temperature of discharged air, as well as the efficiency of the system are analyzed. The theoretical analysis indicates that the additional application of discharged air can improve total energy efficiency by 20–30%. Therefore, this system is very worthy of consideration and being popularized. - Highlights: • The proposed system can provide mechanical energy, heat energy and cooling power. • The exhaust air of pneumatic motor is used as cooling power instead of abandoned. • A thermodynamic model of the proposed system is constructed and validated. • The effects of several parameters on system performance are examined. • The proposed system can improve total energy efficiency of CAES system by 20–30%.

Energirenovering af parcelhuse

DEFF Research Database (Denmark)

Aggerholm, Søren

af de tre huse består i efterisolering af lofter op til 300 mm, udskiftning af almindelige termoruder til energiruder, og installation af solvarmeanlæg til produktion af varmt brugsvand. I de tre huse er der ved energirenoveringen opnået en reduktion af energiforbruget på 16-22 procent. Rapporten...

Photo-acoustic sensor for detection of oil contamination in compressed air systems.

Science.gov (United States)

Lassen, Mikael; Harder, David Baslev; Brusch, Anders; Nielsen, Ole Stender; Heikens, Dita; Persijn, Stefan; Petersen, Jan C

2017-02-06

We demonstrate an online (in-situ) sensor for continuous detection of oil contamination in compressed air systems complying with the ISO-8573 standard. The sensor is based on the photo-acoustic (PA) effect. The online and real-time PA sensor system has the potential to benefit a wide range of users that require high purity compressed air. Among these are hospitals, pharmaceutical industries, electronics manufacturers, and clean room facilities. The sensor was tested for sensitivity, repeatability, robustness to molecular cross-interference, and stability of calibration. Explicit measurements of hexane (C6H14) and decane (C10H22) vapors via excitation of molecular C-H vibrations at approx. 2950 cm-1 (3.38 μm) were conducted with a custom made interband cascade laser (ICL). For the decane measurements a (1 σ) standard deviation (STD) of 0.3 ppb was demonstrated, which corresponds to a normalized noise equivalent absorption (NNEA) coefficient for the prototype PA sensor of 2.8×10-9 W cm-1 Hz1/2.

Factors that influence the tribocharging of pulverulent materials in compressed-air devices

Energy Technology Data Exchange (ETDEWEB)

Das, S; Medles, K; Mihalcioiu, A; Beleca, R; Dragan, C; Dascalescu, L [Laboratory of Aerodynamic Studies, University of Poitiers, University Institute of Technology, Angouleme, 16021 (France)], E-mail: ldascalescu@iutang.univ-poitiers.fr

2008-12-01

Tribocharging of pulverulent materials in compressed-air devices is a typical multi-factorial process. This paper aims at demonstrating the interest of using the design of experiments methodology in association with virtual instrumentation for quantifying the effects of various process varaibles and of their interactions, as a prerequisite for the development of new tribocharging devices for industrial applications. The study is focused on the tribocharging of PVC powders in compressed-air devices similar to those employed in electrostatic painting. A classical 2 full-factorial design (3 factors at two levels) was employed for conducting the experiments. The response function was the charge/mass ratio of the material collected in a modified Faraday cage, at the exit of the tribocharging device. The charge/mass ratio was found to increase with the injection pressure and the vortex pressure in the tribocharging device, and to decrease with the increasing of the feed rate. In the present study an in-house design of experiments software was employed for statistical analysis of experimental data and validation of the experimental model.

Factors that influence the tribocharging of pulverulent materials in compressed-air devices

International Nuclear Information System (INIS)

Das, S; Medles, K; Mihalcioiu, A; Beleca, R; Dragan, C; Dascalescu, L

2008-01-01

Tribocharging of pulverulent materials in compressed-air devices is a typical multi-factorial process. This paper aims at demonstrating the interest of using the design of experiments methodology in association with virtual instrumentation for quantifying the effects of various process varaibles and of their interactions, as a prerequisite for the development of new tribocharging devices for industrial applications. The study is focused on the tribocharging of PVC powders in compressed-air devices similar to those employed in electrostatic painting. A classical 2 full-factorial design (3 factors at two levels) was employed for conducting the experiments. The response function was the charge/mass ratio of the material collected in a modified Faraday cage, at the exit of the tribocharging device. The charge/mass ratio was found to increase with the injection pressure and the vortex pressure in the tribocharging device, and to decrease with the increasing of the feed rate. In the present study an in-house design of experiments software was employed for statistical analysis of experimental data and validation of the experimental model.

Kortlægning af evalueringer og undersøgelser af vejledning knyttet til vejledning af unge i UU-regi

DEFF Research Database (Denmark)

Skovhus, Randi Boelskifte; thomsen, rie

2013-01-01

Kortlægning af evalueringer og undersøgelser af vejledning knyttet til vejledning af unge i UU-regi 2004-2013. Et arbejdspapir......Kortlægning af evalueringer og undersøgelser af vejledning knyttet til vejledning af unge i UU-regi 2004-2013. Et arbejdspapir...

Fremtidssikring af kloaknet

DEFF Research Database (Denmark)

Hansen, Ernst Jan de Place

2008-01-01

Beskrivelse af hvordan man ved udbygning af eksisterende kloaknet og ved nytænkning af planlægning af nye bydele kan sikre sig langsigtet mod konsekvenserne af klimaændinger og kraftigere nedbør...

Estimation of air void and aggregate spatial distributions in concrete under uniaxial compression using computer tomography scanning

International Nuclear Information System (INIS)

Wong, R.C.K.; Chau, K.T.

2005-01-01

Normal- and high-strength concrete cylinders (designed compressive strengths of 30 and 90 MPa at 28 days) were loaded uniaxially. Computer tomography (CT) scanning technique was used to examine the evolution of air voids inside the specimens at various loading states up to 85% of the ultimate compressive strength. The normal-strength concrete yielded a very different behaviour in changes of internal microstructure as compared to the high-strength concrete. There were significant instances of nucleation and growth in air voids in the normal-strength concrete specimen, while the increase in air voids in the high-strength concrete specimen was insignificant. In addition, CT images were used for mapping the aggregate spatial distributions within the specimens. No intrinsic anisotropy was detected from the fabric analysis

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.

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.

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

Energy Technology Data Exchange (ETDEWEB)

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

1981-09-01

An energy storage system which could be attractive for future 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 (FBC) combustor/compressed air energy storage (FBC/CAES) systems was performed and is described. The conclusions drawn from the FBC/CAES study program are encouraging. They indicate that pressurized FBC/CAES power plants should be technologically feasible, provide good performance, and be economically competitive. Specifically, it is concluded that: coal-fired FBC/CAES systems should be technically feasible in the near future and potentially attractive for peak-load power generation; and an open-bed PFBC/CAES configuration would provide the best candidate for early commercialization. It has relatively low risk combined with moderate cost and reasonable round-trip heat rate. It also has the potential for future growth options which tend to reduce costs and lower fuel consumption.

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.

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

OpenAIRE

P Vinay; 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 ...

Energy and Exergy Analysis of Ocean Compressed Air Energy Storage Concepts

Directory of Open Access Journals (Sweden)

Vikram C. Patil

2018-01-01

Full Text Available Optimal utilization of renewable energy resources needs energy storage capability in integration with the electric grid. Ocean compressed air energy storage (OCAES can provide promising large-scale energy storage. In OCAES, energy is stored in the form of compressed air under the ocean. Underwater energy storage results in a constant-pressure storage system which has potential to show high efficiency compared to constant-volume energy storage. Various OCAES concepts, namely, diabatic, adiabatic, and isothermal OCAES, are possible based on the handling of heat in the system. These OCAES concepts are assessed using energy and exergy analysis in this paper. Roundtrip efficiency of liquid piston based OCAES is also investigated using an experimental liquid piston compressor. Further, the potential of improved efficiency of liquid piston based OCAES with use of various heat transfer enhancement techniques is investigated. Results show that adiabatic OCAES shows improved efficiency over diabatic OCAES by storing thermal exergy in thermal energy storage and isothermal OCAES shows significantly higher efficiency over adiabatic and diabatic OCAES. Liquid piston based OCAES is estimated to show roundtrip efficiency of about 45% and use of heat transfer enhancement in liquid piston has potential to improve roundtrip efficiency of liquid piston based OCAES up to 62%.

Electric power generating plant having direct-coupled steam and compressed-air cycles

Science.gov (United States)

Drost, M.K.

1981-01-07

An electric power generating plant is provided with a Compressed Air Energy Storage (CAES) system which is directly coupled to the steam cycle of the generating plant. The CAES system is charged by the steam boiler during off peak hours, and drives a separate generator during peak load hours. The steam boiler load is thereby levelized throughout an operating day.

Electric power generating plant having direct coupled steam and compressed air cycles

Science.gov (United States)

Drost, Monte K.

1982-01-01

An electric power generating plant is provided with a Compressed Air Energy Storage (CAES) system which is directly coupled to the steam cycle of the generating plant. The CAES system is charged by the steam boiler during off peak hours, and drives a separate generator during peak load hours. The steam boiler load is thereby levelized throughout an operating day.

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.

Numerical investigation of a joint approach to thermal energy storage and compressed air energy storage in aquifers

International Nuclear Information System (INIS)

Guo, Chaobin; Zhang, Keni; Pan, Lehua; Cai, Zuansi; Li, Cai; Li, Yi

2017-01-01

Highlights: •One wellbore-reservoir numerical model was built to study the impact of ATES on CAESA. •With high injection temperature, the joint of ATES can improve CAESA performance. •The considerable utilization of geothermal occurs only at the beginning of operations. •Combination of CAESA and ATES can be achieved in common aquifers. -- Abstract: Different from conventional compressed air energy storage (CAES) systems, the advanced adiabatic compressed air energy storage (AA-CAES) system can store the compression heat which can be used to reheat air during the electricity generation stage. Thus, AA-CAES system can achieve a higher energy storage efficiency. Similar to the AA-CAES system, a compressed air energy storage in aquifers (CAESA) system, which is integrated with an aquifer thermal energy storage (ATES) could possibly achieve the same objective. In order to investigate the impact of ATES on the performance of CAESA, different injection air temperature schemes are designed and analyzed by using numerical simulations. Key parameters relative to energy recovery efficiencies of the different injection schemes, such as pressure distribution and temperature variation within the aquifers as well as energy flow rate in the injection well, are also investigated in this study. The simulations show that, although different injection schemes have a similar overall energy recovery efficiency (∼97%) as well as a thermal energy recovery efficiency (∼79.2%), the higher injection air temperature has a higher energy storage capability. Our results show the total energy storage for the injection air temperature at 80 °C is about 10% greater than the base model scheme at 40 °C. Sensitivity analysis reveal that permeability of the reservoir boundary could have significant impact on the system performance. However, other hydrodynamic and thermodynamic properties, such as the storage reservoir permeability, thermal conductivity, rock grain specific heat and rock

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...... af vand og dels CO2-produktion og dermed tørstoftab. Anbefaling om beregning af energiværdi i fermenteret korn vil blive foretaget ud fra resultaterne af et produktionsforsøg med slagtesvin, som er under publicering. Fosforudnyttelse i fermenteret korn undersøges yderligere i et produktionsforsøg med...

Power-to-heat in adiabatic compressed air energy storage power plants for cost reduction and increased flexibility

Science.gov (United States)

Dreißigacker, Volker

2018-04-01

The development of new technologies for large-scale electricity storage is a key element in future flexible electricity transmission systems. Electricity storage in adiabatic compressed air energy storage (A-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. For further improvements in cost efficiencies and flexibility, system modifications are necessary. Therefore, a novel concept regarding the integration of an electrical heating component is investigated. This modification allows increased power plant flexibilities and decreasing component sizes due to the generated high temperature heat with simultaneously decreasing total round trip efficiencies. For an exemplarily A-CAES case simulation studies regarding the electrical heating power and thermal energy storage sizes were conducted to identify the potentials in cost reduction of the central power plant components and the loss in round trip efficiency.

Numerical simulation for the coupled thermo-mechanical performance of a lined rock cavern for underground compressed air energy storage

Science.gov (United States)

Zhou, Shu-Wei; Xia, Cai-Chu; Zhao, Hai-Bin; Mei, Song-Hua; Zhou, Yu

2017-12-01

Compressed air energy storage (CAES) is a technology that uses compressed air to store surplus electricity generated from low power consumption time for use at peak times. This paper presents a thermo-mechanical modeling for the thermodynamic and mechanical responses of a lined rock cavern used for CAES. The simulation was accomplished in COMSOL Multiphysics and comparisons of the numerical simulation and some analytical solutions validated the thermo-mechanical modeling. Air pressure and temperatures in the sealing layer and concrete lining exhibited a similar trend of ‘up-down-down-up’ in one cycle. Significant temperature fluctuation occurred only in the concrete lining and sealing layer, and no strong fluctuation was observed in the host rock. In the case of steel sealing, principal stresses in the sealing layer were larger than those in the concrete and host rock. The maximum compressive stresses of the three layers and the displacement on the cavern surface increased with the increase of cycle number. However, the maximum tensile stresses exhibited the opposite trend. Polymer sealing achieved a relatively larger air temperature and pressure compared with steel and air-tight concrete sealing. For concrete layer thicknesses of 0 and 0.1 m and an initial air pressure of 4.5 MPa, the maximum rock temperature could reach 135 °C and 123 °C respectively in a 30 day simulation.

Work plan for upgrading the 241-A-701 compressed air system and motor control center. Revision 1

International Nuclear Information System (INIS)

Carpenter, K.E.

1995-01-01

This work plan will outline the responsibilities associated with the 241-A-701 Compressed Air System (CAS) and Motor Control Center (MCC) upgrades. All activities required to design, install, test, and operate the modified systems are addressed in this document. Upgrades Technical Support (UTS) of TWRS Engineering is responsible for the completion of all tasks associated with this upgrade. UTS will coordinate the upgrade activities, and ensure all tasks are successfully completed on or before the scheduled dates. The primary objective of the 241-A-701 Compressor and MCC Upgrade is to provide a reliable source of process and instrument compressed air to the A, AX, AY, and AZ tank farms

Compressed breathing air - the potential for evil from within.

Science.gov (United States)

Millar, Ian L; Mouldey, Peter G

2008-06-01

Human underwater activities rely on an adequate supply of breathable compressed gas, usually air, free from contaminants that could cause incapacitation underwater or post-dive or longer-term health effects. Potentially fatal but well-known hazards are hypoxia secondary to steel cylinder corrosion and carbon monoxide (CO) poisoning due to contaminated intake air. Another phenomenon may be behind some previously unexplained episodes of underwater incapacitation and perhaps death: low-level CO poisoning and/or the effects of gaseous contaminants generated within the compressor, including toluene and other volatile compounds. Many low molecular weight volatile contaminants are anaesthetic and will be potentiated by pressure and nitrogen narcosis. In sub-anaesthetic doses, impaired judgement, lowered seizure threshold and sensitisation of the heart to arrhythmias may occur. Toxic compounds can be volatilised from some compressor oils, especially mineral oils, in overheated compressors, or be created de novo under certain combinations of temperature, humidity and pressure, perhaps catalysed by metal traces from compressor wear and tear. Most volatiles can be removed by activated carbon filtration but many filters are undersized and may overload in hot, moist conditions and with short dwell times. A compressor that passes normal testing could contaminate one or more cylinders after heating up and then return to producing clean air as the filters dry and the systems cool. The scope of this problem is very unclear as air quality is tested infrequently and often inadequately, even after fatalities. More research is needed as well as better education regarding the safe operation and limitations of high-pressure breathing air compressors.

Shaping Air Mobility Forces for Future Relevance

Science.gov (United States)

2017-01-01

King Air University Press 600 Chennault Circle, Building 1405 Maxwell AFB, AL 36112-6010 afri.aupress@us.af.mil http://aupress.au.af.mil...the congressional study’s Persian Gulf scenario.37 Later Defense Department air mobility plans continued the CMMS pat- tern of paring down air mobility

Compressed air energy storage technology program. Annual report for 1980

Energy Technology Data Exchange (ETDEWEB)

Kannberg, L.D.

1981-06-01

All of the major research funded under the Compressed Air Energy Storage Technology Program during the period March 1980 to March 1981 is described. This annual report is divided into two segments: Reservoir Stability Studies and Second-Generation Concepts Studies. The first represents research performed to establish stability criteria for CAES reservoirs while the second reports progress on research performed on second-generation CAES concepts. The report consists of project reports authored by research engineers and scientists from PNL and numerous subcontractors including universities, architect-engineering, and other private firms.

Subcooled compressed air energy storage system for coproduction of heat, cooling and electricity

International Nuclear Information System (INIS)

Arabkoohsar, A.; Dremark-Larsen, M.; Lorentzen, R.; Andresen, G.B.

2017-01-01

Highlights: •A new configuration of compressed air energy storage system is proposed and analyzed. •This system, so-called subcooled-CAES, offers cogeneration of electricity, heat and cooling. •A pseudo-dynamic energy, exergy and economic analysis of the system for an entire year is presented. •The annual power, cooling and heat efficiencies of the system are around 31%, 32% and 92%. •The overall energy and exergy performance coefficients of the system are 1.55 and 0.48, respectively. -- Abstract: Various configurations of compressed air energy storage technology have received attention over the last years due to the advantages that this technology offers relative to other power storage technologies. This work proposes a new configuration of this technology aiming at cogeneration of electricity, heat and cooling. The new system may be very advantageous for locations with high penetration of renewable energy in the electricity grid as well as high heating and cooling demands. The latter would typically be locations with district heating and cooling networks. A thorough design, sizing and thermodynamic analysis of the system for a typical wind farm with 300 MW capacity in Denmark is presented. The results show a great potential of the system to support the local district heating and cooling networks and reserve services in electricity market. The values of power-to-power, power-to-cooling and power-to-heat efficiencies of this system are 30.6%, 32.3% and 92.4%, respectively. The exergy efficiency values are 30.6%, 2.5% and 14.4% for power, cooling and heat productions. A techno-economic comparison of this system with two of the most efficient previous designs of compressed air energy storage system proves the firm superiority of the new concept.

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.

Preliminary engineering design and cost of Advanced Compressed-Air Storage (ACAS) A-5 hybrid

Science.gov (United States)

Sosnowicz, E. J.; Blackman, J.; Woodhull, A. S.; Zaugg, P.

1981-08-01

The advanced compressed air energy (ACAS) plant investiated operates on a partial adiabatic, partial fuel fired cycle. Only a limited advancement in state-of-the-art technology is projected for this hybrid arrangement. The A-5 hybrid systems stores the heat of compression from the low pressure and intermediate pressure compressors in a thermal energy store (TES). The heat collected in the TES is available for preheating the air from the storage cavern prior to its entering the low pressure turbine combustor. This reduces the amount of fuel consumed during power generation. The fuel heat rate for the hybrid cycle is 2660 Btu/kWh as compared to approximately 4000 Btu/kWh for a conventional CAES plant. A virtual stand-off between the hybrid plant and a conventional CAES plant at 235 mills/kWh in 1990 dollars is shown. With a lower cost and increased fuel cost projections, the hybrid system operating cost is less than that for a conventional CAES plant.

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....

Sundhedseffekter af luftforurening-beregningspriser

DEFF Research Database (Denmark)

Andersen, M. S.; Frohn, L. M.; Jensen, S. S.

Denne rapport afrapporterer det fortsatte arbejde med udvikling af miljøøkonomiske beregningspriser. På grundlag af EcoSense 4.0 fra ExternE-projektet, er der foretaget nye beregninger af eksternaliteter ved luftforurening med sundhedseffekter. Samtidig giver rapporten en vurdering af luftspredni......Denne rapport afrapporterer det fortsatte arbejde med udvikling af miljøøkonomiske beregningspriser. På grundlag af EcoSense 4.0 fra ExternE-projektet, er der foretaget nye beregninger af eksternaliteter ved luftforurening med sundhedseffekter. Samtidig giver rapporten en vurdering af...

Extra-fibrillar matrix mechanics of annulus fibrosus in tension and compression.

Science.gov (United States)

Cortes, Daniel H; Elliott, Dawn M

2012-07-01

The annulus fibrosus (AF) of the disk is a highly nonlinear and anisotropic material that undergoes a complex combination of loads in multiple orientations. The tensile mechanical behavior of AF in the lamellar plane is dominated by collagen fibers and has been accurately modeled using exponential functions. On the other hand, AF mechanics perpendicular to the lamella, in the radial direction, depend on the properties of the ground matrix with little to no fiber contribution. The ground matrix is mainly composed of proteoglycans (PG), which are negatively charged macromolecules that maintain the tissue hydration via osmotic pressure. The mechanical response of the ground matrix can be divided in the contribution of osmotic pressure and an elastic solid part known as extra-fibrillar matrix (EFM). Mechanical properties of the ground matrix have been measured using tensile and confined compression tests. However, EFM mechanics have not been measured directly. The objective of this study was to measure AF nonlinear mechanics of the EFM in tension and compression. To accomplish this, a combination of osmotic swelling and confined compression in disk radial direction, perpendicular to the lamella, was used. For this type of analysis, it was necessary to define a stress-free reference configuration. Thus, a brief analysis on residual stress in the disk and a procedure to estimate the reference configuration are presented. The proposed method was able to predict similar swelling deformations when using different loading protocols and models for the EFM, demonstrating its robustness. The stress-stretch curve of the EFM was linear in the range 0.9 disk and can be applied to differentiate between functional degeneration effects such as PG loss and stiffening due to cross-linking.

Numerical Investigation of the Influences of Wellbore Flow on Compressed Air Energy Storage in Aquifers

Directory of Open Access Journals (Sweden)

Yi Li

2017-01-01

Full Text Available With the blossoming of intermittent energy, compressed air energy storage (CAES has attracted much attention as a potential large-scale energy storage technology. Compared with caverns as storage vessels, compressed air energy storage in aquifers (CAESA has the advantages of wide availability and lower costs. The wellbore can play an important role as the energy transfer mechanism between the surroundings and the air in CAESA system. In this paper, we investigated the influences of the well screen length on CAESA system performance using an integrated wellbore-reservoir simulator (T2WELL/EOS3. The results showed that the well screen length can affect the distribution of the initial gas bubble and that a system with a fully penetrating wellbore can obtain acceptably stable pressurized air and better energy efficiencies. Subsequently, we investigated the impact of the energy storage scale and the target aquifer depth on the performance of a CAESA system using a fully penetrating wellbore. The simulation results demonstrated that larger energy storage scales exhibit better performances of CAESA systems. In addition, deeper target aquifer systems, which could decrease the energy loss by larger storage density and higher temperature in surrounding formation, can obtain better energy efficiencies.

Anvendelse af alternative isoleringsmaterialer

DEFF Research Database (Denmark)

Hansen, Ernst Jan de Place

2003-01-01

Resume af By og Byg Anvisning 207 om anvendelse af alternative isoleringsmaterialer, udarbejdet af Statens Byggeforskningsinstitut under udviklingsprogrammet "Miljø- og arbejdsmiljøvenlig isolering"......Resume af By og Byg Anvisning 207 om anvendelse af alternative isoleringsmaterialer, udarbejdet af Statens Byggeforskningsinstitut under udviklingsprogrammet "Miljø- og arbejdsmiljøvenlig isolering"...

Beregning af nitratudvaskning

DEFF Research Database (Denmark)

Petersen, Jens; Petersen, Bjørn Molt; Blicher-Mathiesen, Gitte

2006-01-01

I forbindelse med kommunalreformen ønskes en ensartet forvaltning af reglerne for vurdering af virkninger på miljøet (VVM) ved ansøgninger om udvidelse af husdyrbrug, herunder beregning af nitratudvaskningen. Rapporten foreslår et beregningskoncept, der bygger på den ansøgende bedrifts samlede kv...

A method for predicting the impact velocity of a projectile fired from a compressed air gun facility

International Nuclear Information System (INIS)

Attwood, G.J.

1988-03-01

This report describes the development and use of a method for calculating the velocity at impact of a projectile fired from a compressed air gun. The method is based on a simple but effective approach which has been incorporated into a computer program. The method was developed principally for use with the Horizontal Impact Facility at AEE Winfrith but has been adapted so that it can be applied to any compressed air gun of a similar design. The method has been verified by comparison of predicted velocities with test data and the program is currently being used in a predictive manner to specify test conditions for the Horizontal Impact Facility at Winfrith. (author)

Identifikation af referencevandløb til implementering af vandrammedirektivet i Danmark

DEFF Research Database (Denmark)

Kristensen, Esben Astrup; Baattrup-Pedersen, Annette; Skriver, Jens

Definition og beskrivelse af referencetilstanden er centralt for implementering af vandrammedirektivet, da bedømmelse af den økologiske tilstand sker som afvigelsen fra den upåvirkede referencetilstand. I denne rapport præsenteres analyser af danske, udenlandske og historiske data med det formål...

Acute exposure to air pollution triggers atrial fibrillation.

Science.gov (United States)

Link, Mark S; Luttmann-Gibson, Heike; Schwartz, Joel; Mittleman, Murray A; Wessler, Benjamin; Gold, Diane R; Dockery, Douglas W; Laden, Francine

2013-08-27

This study sought to evaluate the association of air pollution with the onset of atrial fibrillation (AF). Air pollution in general and more specifically particulate matter has been associated with cardiovascular events. Although ventricular arrhythmias are traditionally thought to convey the increased cardiovascular risk, AF may also contribute. Patients with dual chamber implantable cardioverter-defibrillators (ICDs) were enrolled and followed prospectively. The association of AF onset with air quality including ambient particulate matter pollution between 2 and 48 h prior to the AF were examined. Of 176 patients followed for an average of 1.9 years, 49 patients had 328 episodes of AF lasting ≥ 30 s. Positive but nonsignificant associations were found for PM2.5 in the prior 24 h, but stronger associations were found with shorter exposure windows. The odds of AF increased by 26% (95% confidence interval: 8% to 47%) for each 6.0 μg/m(3) increase in PM2.5 in the 2 h prior to the event (p = 0.004). The odds of AF were highest at the upper quartile of mean PM2.5. PM was associated with increased odds of AF onset within hours following exposure in patients with known cardiac disease. Air pollution is an acute trigger of AF, likely contributing to the pollution-associated adverse cardiac outcomes observed in epidemiological studies. Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

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...

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...... fremhævelse af den eksistentielle terapi som en praktisk eksistensfænomenologisk livskunst, hvis anliggende er en frembringelse af det enkelte menneskes muligheder fra det skjulte og ind i det uskjulte, så mennesket viser sig som det er ved sig selv...

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.......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....

Energirenovering af Traneparken

DEFF Research Database (Denmark)

Rose, Jørgen; Thomsen, Kirsten Engelund; Mørck, Ove

Nærværende rapport udgør en del af afrapporteringen af PSO ELFORSK projektet Vejledning for energirenovering af boligblokke til lavenergiklasse 2015 og 2020. Arbejdet har været finansieret af PSO midler via ELFORSK, projekt: 347-023. Formålet med projektet er at udvikle en vejledning for dybtgående...

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.

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.

The optimum intermediate pressure of two-stages vapor compression refrigeration cycle for Air-Conditioning unit

Science.gov (United States)

Ambarita, H.; Sihombing, H. V.

2018-03-01

Vapor compression cycle is mainly employed as a refrigeration cycle in the Air-Conditioning (AC) unit. In order to save energy, the Coefficient of Performance (COP) of the need to be improved. One of the potential solutions is to modify the system into multi-stages vapor compression cycle. The suitable intermediate pressure between the high and low pressures is one of the design issues. The present work deals with the investigation of an optimum intermediate pressure of two-stages vapor compression refrigeration cycle. Typical vapor compression cycle that is used in AC unit is taken into consideration. The used refrigerants are R134a. The governing equations have been developed for the systems. An inhouse program has been developed to solve the problem. COP, mass flow rate of the refrigerant and compressor power as a function of intermediate pressure are plotted. It was shown that there exists an optimum intermediate pressure for maximum COP. For refrigerant R134a, the proposed correlations need to be revised.

Increasing the Air Charge and Scavenging the Clearance Volume of a Compression-Ignition Engine

Science.gov (United States)

Spanogle, J A; Hicks, C W; Foster, H H

1934-01-01

The object of the investigation presented in this report was to determine the effects of increasing the air charge and scavenging the clearance volume of a 4-stroke-cycle compression-ignition engine having a vertical-disk form combustion chamber. Boosting the inlet-air pressure with normal valve timing increased the indicated engine power in proportion to the additional air inducted and resulted in smoother engine operation with less combustion shock. Scavenging the clearance volume by using a valve overlap of 145 degrees and an inlet-air boost pressure of approximately 2 1/2 inches of mercury produced a net increase in performance for clear exhaust operation of 33 percent over that obtained with normal valve timing and the same boost pressure. The improved combustion characteristics result in lower specific fuel consumption, and a clearer exhaust.

Design and Analysis of a Solar-Powered Compressed Air Energy Storage System

Science.gov (United States)

2016-12-01

sized PV panel arrays. Kim et al. [49] and Manfrida et al. [50] proposed that a SS-AA- CAES system using COTS parts could be made more economical by...directly improve system efficiency. Furthermore, the power formulas derived using this approach can easily be used to both size the compressor based on...48] Villela, D., Kasinathan, V., De Valle, S., 2010, “Compressed-Air Energy Storage Systems for Stand-Alone Off-Grid Photovoltaic Modules

Om Hegels opfattelse af Gorgias, set på baggrund af tidligere filosofihistorikeres fremstilling

DEFF Research Database (Denmark)

Huggler, Jørgen

2010-01-01

En undersøgelse af Hegels tolkning af sofisten Gorgias giver anledning til at se på receptionen af sofisterne hos notable filosofihistorikere i det 18. århundrede. En sådan undersøgelse viser, at Hegel har en original og velvillig tolkning af sofisterne koncentreret omkring begrebet Bildung og det...... at give grunde for noget. Hegels udlægning af Gorgias bygger på hans tolkning af eleaterne, især af Zenon. Når Hegel har en særlig tolkning af eleaterne, skyldes det hans egne mangeårige filosofiske bestræbelser, og en identificering af en særlig, immanent objektiv dialektik hos Zenon, som han finder......, at Gorgias fører videre. Hegels filosofiske forståelse er tilstrækkelig udviklet til at kunne knytte positive kommentarer til alle dele af diskussionen i Gorgias' ræsonnement Om det ikkeværende, eller Om naturen. Det lykkes dog bedst i forhold til de to første af Gorgias' tre underteser. I hegelsk perspektiv...

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 bid...... bidrager kanonen til faglig styrkelse?" spørges der. Det vises, at flere kanonpunkter ikke er fagligt funderede, men af mytologisk art....

Numerical analysis for two-dimensional compressible and two-phase flow fields of air-water in Eulerian grid framework

International Nuclear Information System (INIS)

Park, Chan Wook; Lee, Sung Su

2008-01-01

Two-phase compressible flow fields of air-water are investigated numerically in the fixed Eulerian grid framework. The phase interface is captured via volume fractions of ech phase. A way to model two phase compressible flows as a single phase one is found based on an equivalent equation of states of Tait's type for a multiphase cell. The equivalent single phase field is discretized using the Roe's approximate Riemann solver. Two approaches are tried to suppress the pressure oscillation phenomena at the phase interface, a passive advection of volume fraction and a direct pressure relaxation with the compressible form of volume fraction equation. The direct pressure equalizing method suppresses pressure oscillation successfully and generates sharp discontinuities, transmitting and reflecting acoustic waves naturally at the phase interface. In discretizing the compressible form of volume fraction equation, phase interfaces are geometrically reconstructed to minimize the numerical diffusion of volume fraction and relevant variables. The motion of a projectile in a water-filled tube which is fired by the release of highly pressurized air is simulated presuming the flow field as a two dimensional one, and several design factors affecting the projectile movement are investigated

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....

Open air-vapor compression refrigeration system for air conditioning and hot water cooled by cool water

International Nuclear Information System (INIS)

Hou Shaobo; Li Huacong; Zhang Hefei

2007-01-01

This paper presents an open air-vapor compression refrigeration system for air conditioning and hot water cooled by cool water and proves its feasibility through performance simulation. Pinch technology is used in analysis of heat exchange in the surface heat exchanger, and the temperature difference at the pinch point is selected as 6 o C. Its refrigeration depends mainly on both air and vapor, more efficient than a conventional air cycle, and the use of turbo-machinery makes this possible. This system could use the cool in the cool water, which could not be used to cool air directly. Also, the heat rejected from this system could be used to heat cool water to 33-40 o C. The sensitivity analysis of COP to η c and η t and the simulated results T 4 , T 7 , T 8 , q 1 , q 2 and W m of the cycle are given. The simulations show that the COP of this system depends mainly on T 7 , η c and η t and varies with T 3 or T wet and that this cycle is feasible in some regions, although the COP is sensitive to the efficiencies of the axial compressor and turbine. The optimum pressure ratio in this system could be lower, and this results in a fewer number of stages of the axial compressor. Adjusting the rotation speed of the axial compressor can easily control the pressure ratio, mass flow rate and the refrigerating capacity. The adoption of this cycle will make the air conditioned room more comfortable and reduce the initial investment cost because of the obtained very low temperature air. Humid air is a perfect working fluid for central air conditioning and no cost to the user. The system is more efficient because of using cool water to cool the air before the turbine. In addition, pinch technology is a good method to analyze the wet air heat exchange with water

Styring af kommunal digitalisering

DEFF Research Database (Denmark)

Jæger, Birgit

2017-01-01

Digitalisering af både interne arbejdsprocesser og kommunikation med borgere og virksomheder har længe været en vigtig faktor i moderniseringen af den offentlige sektor. Derfor er der stort fokus på styring af digitaliseringen. Denne artikel undersøger, dels hvordan digitaliseringen i den kommunale...... sektor styres, og dels hvilke styringsparadigmer der kan identificeres. Med udgangspunkt i en konkret kommune analyseres styringen af digitalisering gennem et hierarki af offentlige digitaliseringsstrategier. Gennem udvikling af en helt ny form for organisering, en såkaldt Digitaliseringsforening...

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.

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.

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

Modernisation of compressed-air production in the heating power station of a university hospital; Modernisierung der Drucklufterzeugung im Heizkraftwerk eines Universitaetsklinikums

Energy Technology Data Exchange (ETDEWEB)

Glaser, H. [Landesregierung Schleswig-Holstein (Germany). Reaktorsciherheit

2006-07-15

Compressed air required for the power plant systems (flue gas desulphurisation system, high-pressure superheated steam boilers, gas turbine) and compressed air systems (pneumatic drives and control systems of the technical facilities) of Freiburg university hospital is produced in a large compressor station constructed in 1987, at the same time as the flue gas desulphurisation system of the combined heat and power station. The compressor station consisted of two uncontrolled screw compressors and was inadequate in terms of control, servicing and energy consumption cost. (orig.)

Livscyklusvurdering af basiskemikalier

DEFF Research Database (Denmark)

Olsen, Stig Irving

1998-01-01

Dette resumé af metoder og væsentlige erfaringer fra erhvervsforskerprojektet Livscyklusvurdering af basiskemikalier er skrevet i erkendelse af, at hovedrapporten er for omfattende til en hurtig introduktion i problemstillingerne. Formålet med denne rapport er derfor at give et kort overblik over...

Globalisering af uddannelse

DEFF Research Database (Denmark)

Jensen, Henning Høgh

2005-01-01

Det globale marked for uddannelse er i voldsom vækst og er ved at blive et af Danmarks vigtigste vareområder. Hvorledes kan KVL agere i globaliseringen af uddannelse for at sikre en høj kvalitet af egne kandidater med gode jobmuligheder?...

Impacts of compressed air energy storage plant on an electricity market with a large renewable energy portfolio

International Nuclear Information System (INIS)

Foley, A.; Díaz Lobera, I.

2013-01-01

Renewable energy generation is expected to continue to increase globally due to renewable energy targets and obligations to reduce greenhouse gas emissions. Some renewable energy sources are variable power sources, for example wind, wave and solar. Energy storage technologies can manage the issues associated with variable renewable generation and align non-dispatchable renewable energy generation with load demands. Energy storage technologies can play different roles in each of the step of the electric power supply chain. Moreover, large scale energy storage systems can act as renewable energy integrators by smoothing the variability. Compressed air energy storage is one such technology. This paper examines the impacts of a compressed air energy storage facility in a pool based wholesale electricity market in a power system with a large renewable energy portfolio

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.

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...

Compressed air injection technique to standardize block injection pressures : [La technique d'injection d'air comprimé pour normaliser les pressions d'injection d'un blocage nerveux].

Science.gov (United States)

Tsui, Ban C H; Li, Lisa X Y; Pillay, Jennifer J

2006-11-01

Presently, no standardized technique exists to monitor injection pressures during peripheral nerve blocks. Our objective was to determine if a compressed air injection technique, using an in vitro model based on Boyle's law and typical regional anesthesia equipment, could consistently maintain injection pressures below a 1293 mmHg level associated with clinically significant nerve injury. Injection pressures for 20 and 30 mL syringes with various needle sizes ( 18G, 20G, 21 G, 22G, and 24G) were measured in a closed system. A set volume of air was aspirated into a saline-filled syringe and then compressed and maintained at various percentages while pressure was measured. The needle was inserted into the injection port of a pressure sensor, which had attached extension tubing with an injection plug clamped "off". Using linear regression with all data points, the pressure value and 99% confidence interval (CI) at 50% air compression was estimated. The linearity of Boyle's law was demonstrated with a high correlation, r = 0.99, and a slope of 0.984 (99% CI: 0.967-1.001). The net pressure generated at 50% compression was estimated as 744.8 mmHg, with the 99% CI between 729.6 and 760.0 mmHg. The various syringe/needle combinations had similar results. By creating and maintaining syringe air compression at 50% or less, injection pressures will be substantially below the 1293 mmHg threshold considered to be an associated risk factor for clinically significant nerve injury. This technique may allow simple, real-time and objective monitoring during local anesthetic injections while inherently reducing injection speed. Présentement, aucune technique normalisée ne permet de vérifier les pressions d'injection pendant les blocages nerveux périphériques. Nous voulions vérifier si une technique d'injection d'air comprimé, utilisant un modèle in vitro fondé sur la loi de Boyle et du matériel propre à l'anesthésie régionale, pouvait maintenir avec régularité les

Potential petrophysical and chemical property alterations in a compressed air energy storage porous rock reservoir

Energy Technology Data Exchange (ETDEWEB)

Stottlemyre, J.A.; Erikson, R.L.; Smith, R.P.

1979-10-01

Successful commercialization of Compressed Air Energy Storage (CAES) systems depends on long-term stability of the underground reservoirs subjected to somewhat unique operating conditions. Specifically, these conditions include elevated and time varying temperatures, effective stresses, and air humidities. To minimize the requirements for premium fuels, it may be desirable to retain the thermal energy of compression. Porous media, e.g., sandstone, may hold promise as elevated temperature reservoirs. In this study, a reservoir composed of clean quartz sandstone and injection air temperatures of 300 to 575/sup 0/K are assumed. Numerical modeling is used to estimate temperature, stress, and humidity conditions within this reference porous media reservoir. A discussion on relative importance to CAES of several potential porous media damage mechanisms is presented. In this context, damage is defined as a reduction in intrinsic permeability (measure of air transport capability), a decrease in effective porosity (measure of storage capability), or an increase in elastic and/or inelastic deformation of the porous material. The potential damage mechanisms presented include: (1) disaggregation, (2) particulate plugging, (3) boundary layer viscosity anomalies, (4) inelastic microstructural consolidation, (5) clay swelling and dispersion, (6) hydrothermal mineral alteration, (7) oxidation reactions, and (8) well casing corrosion. These mechanisms are placed in perspective with respect to anticipated CAES conditions and mechanisms suggested are: (1) of academic interest only, (2) readily identified and controlled via engineering, or (3) potential problem areas requiring additional investigation.

Optimization of diesel engine performances for a hybrid wind-diesel system with compressed air energy storage

International Nuclear Information System (INIS)

Ibrahim, H.; Younes, R.; Basbous, T.; Ilinca, A.; Dimitrova, M.

2011-01-01

Electricity supply in remote areas around the world is mostly guaranteed by diesel generators. This relatively inefficient and expensive method is responsible for 1.2 million tons of greenhouse gas (GHG) emission in Canada annually. Some low- and high-penetration wind-diesel hybrid systems (WDS) have been experimented in order to reduce the diesel consumption. We explore the re-engineering of current diesel power plants with the introduction of high-penetration wind systems together with compressed air energy storage (CAES). This is a viable alternative to major the overall percentage of renewable energy and reduce the cost of electricity. In this paper, we present the operative principle of this hybrid system, its economic benefits and advantages and we finally propose a numerical model of each of its components. Moreover, we are demonstrating the energy efficiency of the system, particularly in terms of the increase of the engine performance and the reduction of its fuel consumption illustrated and supported by a village in northern Quebec. -- Highlights: → The Wind-Diesel-Compressed Air Storage System (WDCAS) has a very important commercial potential for remote areas. → The WDCAS is conceived like the adaptation of the existing engines at the level of the intake system. → A wind turbine and an air compression and storage system are added on the diesel plant. → This study demonstrates the potential of WDCAS to reduce fuel consumption and increase the efficiency of the diesel engine. → This study demonstrates that we can expect savings which can reach 50%.

6 belysninger af vejledning

DEFF Research Database (Denmark)

Toft, Helle Mary; Jessing, Carla Tønder; Nymann, Anette

Artiklerne belyser vejledning af unge og vejledning af voksne. I relation til unge drejer det sig om: 1. vejledning af unge med vanskeligheder i forhold til uddannelse - her unge med særlige vejledningsbehov, og mentorordninger for unge, og 2. vejledning af unge i ungdomsuddannelser og i erhvervs...

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"...

Controlled auto-ignition characteristics of methane-air mixture in a rapid intake compression and expansion machine

Energy Technology Data Exchange (ETDEWEB)

Cho, Gyubaek; Jeong, Dongsoo [Engine Research Team, Eco-Machinery Research Division, Korea Institute of Machinery and Materials, 104 Sinseongno, Yuseong-gu, Daejeon 305-701 (Korea); Moon, Gunfeel [Department of Clean Environmental system, University of Science and Technology, 52 Eoeun-dong, Yuseong-gu, Daejeon (Korea); Bae, Choongsik [Engine Laboratory, Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 373-1 GuSeong-Dong, Yuseong-Gu, Daejeon 305-701 (Korea)

2010-10-15

The characteristics of controlled auto-ignition (CAI) were investigated with a methane-air mixture and simulated residual gas, that represents internal exhaust gas recirculation (IEGR). Supply systems were additionally installed on the conventional rapid compression machine (RCM), and this modified machine - a rapid intake compression and expansion machine (RICEM) - was able to simulate an intake stroke for the evaluation of controlled auto-ignition with fuel-air mixture. The fuel-air mixture and the simulated residual gas were introduced separately into the combustion chamber through the spool valves. Various IEGR rates and temperatures of the IEGR gas were tested. The initial reaction and the development in controlled auto-ignition combustion were compared with spark-ignited combustion by visualization with a high-speed digital camera. Under the controlled auto-ignition operation, multi-point ignition and faster combustion were observed. With increasing the temperature of IEGR gas, the auto-ignition timing was advanced and burning duration was shortened. The higher rate of IEGR had the same effects on the combustion of the controlled auto-ignition. However, this trend was reversed with more than 47 per cent of IEGR. (author)

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

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.

A Scramjet Compression System for Hypersonic Air Transportation Vehicle Combined Cycle Engines

Directory of Open Access Journals (Sweden)

Devendra Sen

2018-06-01

Full Text Available This paper proposes a compression system for a scramjet, to be used as part of a combined cycle engine on a hypersonic transport vehicle that can achieve sustained flight at 8 Mach 8. Initially research into scramjet compression system and shock wave interaction was conducted to establish the foundation of the scramjet inlet and isolator sections. A Computational Fluid Dynamics (CFD campaign was conducted, where the shock structure and flow characteristics was analysed between Mach 4.5–8. The compression system of a scramjet is of crucial importance in providing air at suitable Mach number, pressure and temperature to the combustion chamber. The use of turbojet engines in over-under configuration with the scramjet was investigated as well as the study of a combined cycle scramjet-ramjet configuration. It was identified that locating the scramjet in the centre with a rotated ramjet on either side, where its ramps make up the scramjet wall was the most optimal configuration, as it mitigated the effect of the oblique shocks propagating from the scramjet walls into the adjacent ramjet. Furthermore, this meant that the forebody of the vehicle could solely be used as the compression surface by the scramjet. In this paper, the sizing of the scramjet combustion chamber and nozzle were modified to match the flow properties of the oncoming flow with the purpose of producing the most optimum scramjet configuration for the cruise speed of Mach 8. CFD simulations showed that the scramjet inlet did not provide the levels of compression and stagnation pressure recovery initially required. However, it was found that the scramjet provided significantly more thrust than the drag of the aircraft at sustained Mach 8 flight, due to its utilisation of a very aerodynamic vehicle design.

Behandling af elmesyge

DEFF Research Database (Denmark)

Thomsen, Iben Margrete; Kristoffersen, Palle

2004-01-01

Ingen midler er p.t. godkendt og dermed lovlige til bekæmpelse af elmesyge i Danmark. Lovprisning af nye behandlinger ses f.eks. på internettet, men dokumentation mangler. Økonomien og nytten ved en kemisk bekæmpelse frem for sanering af syge træer skal afvejes nøje....

Energirenovering af Sems Have

DEFF Research Database (Denmark)

Jensen, Søren Østergaard; Rose, Jørgen; Mørck, Ove

Nærværende rapport udgør en del af afrapporteringen af PSO ELFORSK projektet Vejledning for energirenovering af boligblokke til lavenergiklasse 2015 og 2020. Arbejdet har været finansieret af PSO midler via ELFORSK, projekt: 347-023. Formålet med projektet er at udvikle en vejledning for dybtgående...

A comparative experimental study on engine operating on premixed charge compression ignition and compression ignition mode

Directory of Open Access Journals (Sweden)

Bhiogade Girish E.

2017-01-01

Full Text Available New combustion concepts have been recently developed with the purpose to tackle the problem of high emissions level of traditional direct injection Diesel engines. A good example is the premixed charge compression ignition combustion. A strategy in which early injection is used causing a burning process in which the fuel burns in the premixed condition. In compression ignition engines, soot (particulate matter and NOx emissions are an extremely unsolved issue. Premixed charge compression ignition is one of the most promising solutions that combine the advantages of both spark ignition and compression ignition combustion modes. It gives thermal efficiency close to the compression ignition engines and resolves the associated issues of high NOx and particulate matter, simultaneously. Premixing of air and fuel preparation is the challenging part to achieve premixed charge compression ignition combustion. In the present experimental study a diesel vaporizer is used to achieve premixed charge compression ignition combustion. A vaporized diesel fuel was mixed with the air to form premixed charge and inducted into the cylinder during the intake stroke. Low diesel volatility remains the main obstacle in preparing premixed air-fuel mixture. Exhaust gas re-circulation can be used to control the rate of heat release. The objective of this study is to reduce exhaust emission levels with maintaining thermal efficiency close to compression ignition engine.

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...

Af Upraktiske Grunde

DEFF Research Database (Denmark)

Vaaben, Nana Katrine

2001-01-01

som både Claude Levi-Strauss lægger op til i sine klassiske studier af "den vilde tanke", og som Jean Baudrillard siden har lagt op til i sine analyser af samlere som en slags ekstreme forbrugere, der er i færd med at komplettere deres identitet gennem besiddelser af genstande. Imidlertid tillægger...

Ledelse af projektmyldret

DEFF Research Database (Denmark)

større arbejdsgrupper, og det kan være selvorganiserede store udviklingsprogrammer. Et projekt kører sjældent alene, og derfor er der ikke kun tale om projektledelse, men i lige så høj grad om ledelse af projekter. Ledelse af virksomhedens mylder af projekter er ikke let, og forfatterne gennemgår derfor...

Evaluering af ordning med psykologbehandling af personer med let til moderat depression

DEFF Research Database (Denmark)

Fjeldsted, Rita; Christensen, Kaj Sparle

Herværende rapport evaluerer den pr. 1.4.2008 indførte ordning med mulighed for henvisning til psykologbehandling med 60 % tilskud for patienter med let til moderat depression. Evalueringen har betjent sig af flere gensidigt supplerende metoder: spørgeskemaundersøgelser overfor patienter, psykolo......Herværende rapport evaluerer den pr. 1.4.2008 indførte ordning med mulighed for henvisning til psykologbehandling med 60 % tilskud for patienter med let til moderat depression. Evalueringen har betjent sig af flere gensidigt supplerende metoder: spørgeskemaundersøgelser overfor patienter...... tidligere evaluering af forsøgsordning af psykologbehandling af depression i perioden 2005-06. 18.419 personer i alderen 18-37 år blev henvist til psykolog i den undersøgte ordning i perioden 1.2.2009 – 31.1.2010, svarende til en henvisningshyppighed på 1,6 % af baggrundsbefolkningen i samme aldersgruppe....... Ordningen giver mulighed for én rehenvisning, og 9 % blev rehenvist i perioden. Spørgeskemaresultater viser, at kun 33 % af de henviste falder ind under henvisningskriteriet ” let til moderat depression” på tidspunktet for opstart af psykologbehandling, 39 % har ingen tegn på depression, og 28 % har svær...

Evaluering af metoder til risikovurdering af kombinationseffekter og etablering af PBTK/TD modeller for pesticider - et ph.d.-projekt

DEFF Research Database (Denmark)

Reffstrup, Trine Klein

2012-01-01

I dette ph.d.-projekt ved DTU Fødevareinstituttet er den nuværende viden om metoder til risikovurdering af kombinationseffekter af kemiske stoffer med fokus på pesticider gennemgået. Endvidere undersøgtes, hvordan man kan implementere matematiske computermodeller som et værktøj i vurderingen af...

Pressure Regulators as Valves for Saving Compressed Air and their Influence on System Dynamics

Directory of Open Access Journals (Sweden)

Dvořák Lukáš

2015-01-01

Full Text Available Pressure regulators in the field of pneumatic mechanisms can be used as valves for saving compressed air. For example it can be used to reduce the pressure when the piston rod is retracting unloaded and thus it is possible to save some energy. However the problem is that saving valve can significantly affect the dynamics of the pneumatic system. The lower pressure in the piston rod chamber causes extension of time for retraction of the piston rod. This article compare the air consumption experimentally determined and calculated, measured curves of pressure in cylinder chambers and piston speed when saving valve is set up differently.

Pressure Regulators as Valves for Saving Compressed Air and their Influence on System Dynamics

Science.gov (United States)

Dvořák, Lukáš; Fojtášek, Kamil

2015-05-01

Pressure regulators in the field of pneumatic mechanisms can be used as valves for saving compressed air. For example it can be used to reduce the pressure when the piston rod is retracting unloaded and thus it is possible to save some energy. However the problem is that saving valve can significantly affect the dynamics of the pneumatic system. The lower pressure in the piston rod chamber causes extension of time for retraction of the piston rod. This article compare the air consumption experimentally determined and calculated, measured curves of pressure in cylinder chambers and piston speed when saving valve is set up differently.

Air ejector augmented compressed air energy storage system

Science.gov (United States)

Ahrens, F.W.; Kartsounes, G.T.

Energy is stored in slack demand periods by charging a plurality of underground reservoirs with air to the same peak storage pressure, during peak demand periods throttling the air from one storage reservoir into a gas turbine system at a constant inlet pressure until the air presure in the reservoir falls to said constant inlet pressure, thereupon permitting air in a second reservoir to flow into said gas turbine system while drawing air from the first reservoir through a variable geometry air ejector and adjusting said variable geometry air ejector, said air flow being essentially at the constant inlet pressure of the gas turbine system.

Snit af målinger: VK afhængig af DF og NA

DEFF Research Database (Denmark)

Thomsen, Søren Risbjerg

2007-01-01

ANALYSE: Ekstra Risbjerg-snit af meningsmålinger grundet fortsat valgrummel - VK-regeringen vil blive afhængig af både DF og NA. Udgivelsesdato: 21. august 2007......ANALYSE: Ekstra Risbjerg-snit af meningsmålinger grundet fortsat valgrummel - VK-regeringen vil blive afhængig af både DF og NA. Udgivelsesdato: 21. august 2007...

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.

Carbon and Energy Saving Financial Opportunities in the Industrial Compressed Air Sector

Science.gov (United States)

Vittorini, Diego; Cipollone, Roberto

2017-08-01

The transition towards a more sustainable energy scenario calls for both medium-to-long and short term interventions, with CO2 reduction and fossil fuel saving as main goals for all the Countries in the World. Among all others, one way to support these efforts is the setting-up of immaterial markets able to regulate, in the form of purchase and sales quotas, CO2 emissions avoided and fossil fuels not consumed. As a consequence, the upgrade of those sectors, characterized by high energy impact, is currently more than an option due to the related achievable financial advantage on the afore mentioned markets. Being responsible for about 10% electricity consumption in Industry, the compressed air sector is currently addressed as extremely appealing, when CO2 emissions and burned fossil fuels saving are in question. In the paper, once a standard is defined for compressors performances, based on data from the Compressed Air and Gas Institute and PNEUROP, the achievable energy saving is evaluated along with the effect in terms of CO2 emissions: with reference to those contexts in which mature intangible markets are established, an estimation of the financial benefit from savings sale on correspondent markets is possible, in terms of both avoided CO2 and fossil fuels not burned. The approach adopted allows to extend the analysis results to every context of interest, by applying the appropriate emission factor to the datum on compressor specific consumption.

Optimering af model for spredning af luftforurening

DEFF Research Database (Denmark)

Pedersen, Jens Christian

2008-01-01

De nuværende luftforureningsmodeller har problemer med at bevare massen af diverse kemiske stoffer og med at der ind i mellem optræder negative værdier. Derfor arbejder specialestuderende Ayoe Buus Hansen på om at forbedre den model DMU bruger til at beskrive transport og spredning af luftforuren...... luftforurening på alle skalaer på den nordlige halvkugle ved at sammenligne tre alternative beregningsmodeller. ...

Chironomus plumosus' påvirkning af næringsstofflukse i restaurerede søer

DEFF Research Database (Denmark)

Kristensen, T. B.; Reitzel, K.; Andersen, F. Ø.

Den interne næringsstofbelastning af en række danske søer har betydet at disse søer er forblevet i en uklar, algedomineret tilstand til trods for reduktioner i mængden af tilførte næringsstoffer. I mange tilfælde er der derfor efterfølgende lavet et eller flere restaureringsindgreb for at skabe e....... plumosus efter længere tid vil øge bindingen af fosfor.   Andersen,F.Ø.; Jørgensen,M.; Jensen, H.S. (2006). The influence of Chironomus plumosus larvae on nutrient fluxes and phosphorus fractions in aluminum treated lake sediment. Water, Air, and Soil Pollution: Focus....

Modelling and analysis of a novel compressed air energy storage system for trigeneration based on electrical energy peak load shifting

International Nuclear Information System (INIS)

Lv, Song; He, Wei; Zhang, Aifeng; Li, Guiqiang; Luo, Bingqing; Liu, Xianghua

2017-01-01

Highlights: • A new CAES system for trigeneration based on electrical peak load shifting is proposed. • The theoretical models and the thermodynamics process are established and analyzed. • The relevant parameters influencing its performance have been discussed and optimized. • A novel energy and economic evaluation methods is proposed to evaluate the performance of the system. - Abstract: The compressed air energy storage (CAES) has made great contribution to both electricity and renewable energy. In the pursuit of reduced energy consumption and relieving power utility pressure effectively, a novel trigeneration system based on CAES for cooling, heating and electricity generation by electrical energy peak load shifting is proposed in this paper. The cooling power is generated by the direct expansion of compressed air, and the heating power is recovered in the process of compression and storage. Based on the working principle of the typical CAES, the theoretical analysis of the thermodynamic system models are established and the characteristics of the system are analyzed. A novel method used to evaluate energy and economic performance is proposed. A case study is conducted, and the economic-social and technical feasibility of the proposed system are discussed. The results show that the trigeneration system works efficiently at relatively low pressure, and the efficiency is expected to reach about 76.3% when air is compressed and released by 15 bar. The annual monetary cost saving annually is about 53.9%. Moreover, general considerations about the proposed system are also presented.

Thermodynamic analysis of a novel hybrid wind-solar-compressed air energy storage system

International Nuclear Information System (INIS)

Ji, Wei; Zhou, Yuan; Sun, Yu; Zhang, Wu; An, Baolin; Wang, Junjie

2017-01-01

Highlights: • We present a novel hybrid wind-solar-compressed air energy storage system. • Wind and solar power are transformed into stable electric energy and hot water. • The system output electric power is 8053 kWh with an exergy efficiency of 65.4%. • Parametric sensitivity analysis is presented to optimize system performance. - Abstract: Wind and solar power have embraced a strong development in recent years due to the energy crisis in China. However, owing to their nature of fluctuation and intermittency, some power grid management problems can be caused. Therefore a novel hybrid wind-solar-compressed air energy storage (WS-CAES) system was proposed to solve the problems. The WS-CAES system can store unstable wind and solar power for a stable output of electric energy and hot water. Also, combined with organic Rankin cycle (ORC), the cascade utilization of energy with different qualities was achieved in the WS-CAES system. Aiming to obtain the optimum performance, the analysis of energy, exergy and parametric sensitivity were all conducted for this system. Furthermore, exergy destruction ratio of each component in the WS-CAES system was presented. The results show that the electric energy storage efficiency, round trip efficiency and exergy efficiency can reach 87.7%, 61.2% and 65.4%, respectively. Meanwhile, the parameters analysis demonstrates that the increase of ambient temperature has a negative effect on the system performance, while the increase of turbine inlet temperature has a positive effect. However, when the air turbine inlet pressure varies, there is a tradeoff between the system performance and the energy storage density.

Compressed air storage with humidification (CASH) coal gasification power plant investigation

International Nuclear Information System (INIS)

Nakhamkin, M.; Patel, M.

1991-08-01

A study was performed to investigate and develop a hybrid coal gasification concept which utilizes an air saturator (AS) with an integrated coal gasification/compressed air energy storage (CGS/CAES) plant. This potentially attractive concept is designated as AS/CGS/CAES. In this concept, the coal gasification system provides fuel for the combustors of the CAES reheat turbomachinery train. Motive air from underground storage is humidified by saturators and thereby provides increased power production without additional air consumption. The heat for generating the hot water utilized in the saturators is extracted from waste heat within the overall plant. Multiple alternatives were considered and parametrically analyzed in the study in order to select the most thermodynamically and economically attractive concepts. The major alternatives were differentiated by the type of gasifier, type of CAES turbomachinery, mode of operation, and utilization of waste heat. The results of the study indicate that the use of the air saturation in AS/CGS/CAES plants might reduce capital costs of coal gasification based power used in intermediate load generation by $300 to $400 per kilowatt. Furthermore, heat rates might also be reduced by almost 1.5 cents per kilowatt hour, a major reduction. The major cause of the reduction in electricity costs is a 50% reduction in the required gasification capacity per net kW. In addition to being a load management tool, AS/CGS/CAES concepts provide a method to operate the CGS and turbomachinery in a continuous mode, improving the operation and potentially the life expectancy of both components. 3 refs., 18 figs., 4 tabs

[Research on the incidence of decompression sickness in compressed air works. The development of its recent five years' study].

Science.gov (United States)

Mano, Y; Shibayama, M; Matsui, Y

1987-07-01

Compressed air works have been used as the safest construction work for the basic underground or underwater compressed shield or caisson works in Japan; however, the workers who were exposed to the compressed fields must have put themselves at risk of decompression sickness. Decompression sickness is generally considered to be due to the bubble effects and the bubbles originate from the supersaturated gas dissolved in the blood and other tissues. The standard decompression schedule by the Ministry of Labor has been practically applied at the end of compressed air works, and the laborers decompress slowly from the bottom pressure to the surface according to the schedule. It is difficult to completely prevent the sickness and the average percentage of contracting "bends," using the Japanese standard decompression schedule, is considered to be 0.54%. But previous papers reported higher incidences from 1.42 to 3.3% or more. We have continued an actual investigation on the incidence, and the number of the exposed trials amounted to nearly a hundred thousand. These data were compared between recent five years' group and before. Eventually, it was ascertained that the incidence has been significantly decreased in the recent five years; however, greater care in occupational safety control is still needed.

Wave energy devices with compressible volumes.

Science.gov (United States)

Kurniawan, Adi; Greaves, Deborah; Chaplin, John

2014-12-08

We present an analysis of wave energy devices with air-filled compressible submerged volumes, where variability of volume is achieved by means of a horizontal surface free to move up and down relative to the body. An analysis of bodies without power take-off (PTO) systems is first presented to demonstrate the positive effects a compressible volume could have on the body response. Subsequently, two compressible device variations are analysed. In the first variation, the compressible volume is connected to a fixed volume via an air turbine for PTO. In the second variation, a water column separates the compressible volume from another volume, which is fitted with an air turbine open to the atmosphere. Both floating and bottom-fixed, axisymmetric, configurations are considered, and linear analysis is employed throughout. Advantages and disadvantages of each device are examined in detail. Some configurations with displaced volumes less than 2000 m 3 and with constant turbine coefficients are shown to be capable of achieving 80% of the theoretical maximum absorbed power over a wave period range of about 4 s.

Use of backboard and deflation improve quality of chest compression when cardiopulmonary resuscitation is performed on a typical air inflated mattress configuration.

Science.gov (United States)

Oh, Jaehoon; Kang, Hyunggoo; Chee, Youngjoon; Lim, Taeho; Song, Yeongtak; Cho, Youngsuk; Je, Sangmo

2013-02-01

No study has examined the effectiveness of backboards and air deflation for achieving adequate chest compression (CC) depth on air mattresses with the typical configurations seen in intensive care units. To determine this efficacy, we measured mattress compression depth (MCD, mm) on these surfaces using dual accelerometers. Eight cardiopulmonary resuscitation providers performed CCs on manikins lying on 4 different surfaces using a visual feedback system. The surfaces were as follows: A, a bed frame; B, a deflated air mattress placed on top of a foam mattress laid on a bed frame; C, a typical air mattress configuration with an inflated air mattress placed on a foam mattress laid on a bed frame; and D, C with a backboard. Deflation of the air mattress decreased MCD significantly (B; 14.74 ± 1.36 vs C; 30.16 ± 3.96, P deflation of the air mattress decreased MCD more than use of a backboard (B; 14.74 ± 1.36 vs D; 25.46 ± 2.89, P = 0.002). The use of a both a backboard and a deflated air mattress in this configuration reduces MCD and thus helps achieve accurate CC depth during cardiopulmonary resuscitation.

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...

Udforskning af journalistiske moralnormer

DEFF Research Database (Denmark)

Mogensen, Kirsten

2010-01-01

Kirsten Mogensen beskriver professionelle journalistiske normer. Med udgangspunkt i amerikansk tv's dækning af begivenhederne 11. september kombinerer Kirsten Mogensen kvalitative interviews og tekstanalyse for på den måde at beskrive professionelle journalistiske normer. Metoden er en kombinatio...... af halvstrukturerede, udforskende interviews med både kvantitative og kvalitative analyser af den faktiske dækning, og er primært udledt af Alf Ross' essay om normer og direktiver....

Combined compressed air storage-low BTU coal gasification power plant

Science.gov (United States)

Kartsounes, George T.; Sather, Norman F.

1979-01-01

An electrical generating power plant includes a Compressed Air Energy Storage System (CAES) fueled with low BTU coal gas generated in a continuously operating high pressure coal gasifier system. This system is used in coordination with a continuously operating main power generating plant to store excess power generated during off-peak hours from the power generating plant, and to return the stored energy as peak power to the power generating plant when needed. The excess coal gas which is produced by the coal gasifier during off-peak hours is stored in a coal gas reservoir. During peak hours the stored coal gas is combined with the output of the coal gasifier to fuel the gas turbines and ultimately supply electrical power to the base power plant.

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.

Pilotprojekt - In situ test af stimuleret aerob nedbrydning til oprensning af pesticidpunktkilder

DEFF Research Database (Denmark)

Tsitonaki, Katerina; Roost, Sandra; Larsen, Lars

Denne rapport omhandler et pilotforsøg i felten, hvor det er undersøgt, hvorvidt aerob nedbrydning af phenoxysyre-pesticider kan stimuleres ved tilsætning af ilt suppleret med tilsætning af specifikke pesticidnedbrydende bakterier. Forsøget er udført på en forurenet lokalitet, Skelstofte, hvor der...

TECHNOLOGIES TO ENHANCE THE OPERATION OF EXISTING NATURAL GAS COMPRESSION INFRASTRUCTURE - MANIFOLD DESIGN FOR CONTROLLING ENGINE AIR BALANCE

Energy Technology Data Exchange (ETDEWEB)

Gary D. Bourn; Ford A. Phillips; Ralph E. Harris

2005-12-01

This document provides results and conclusions for Task 15.0--Detailed Analysis of Air Balance & Conceptual Design of Improved Air Manifolds in the ''Technologies to Enhance the Operation of Existing Natural Gas Compression Infrastructure'' project. SwRI{reg_sign} is conducting this project for DOE in conjunction with Pipeline Research Council International, Gas Machinery Research Council, El Paso Pipeline, Cooper Compression, and Southern Star, under DOE contract number DE-FC26-02NT41646. The objective of Task 15.0 was to investigate the perceived imbalance in airflow between power cylinders in two-stroke integral compressor engines and develop solutions via manifold redesign. The overall project objective is to develop and substantiate methods for operating integral engine/compressors in gas pipeline service, which reduce fuel consumption, increase capacity, and enhance mechanical integrity.

Intelligent styring af dynamisk LED belysning

DEFF Research Database (Denmark)

Thorseth, Anders; Corell, Dennis Dan; Hansen, Søren Stentoft

Denne slutrapport giver en kort beskrivelse af arbejdet, der er udført af DTU Fotonik i projektet ”Intelligent styring af dynamisk LED belysning” støttet af EUDP. Arbejdet er udført i perioden 2011‐2012 i samarbejde med Lighten.......Denne slutrapport giver en kort beskrivelse af arbejdet, der er udført af DTU Fotonik i projektet ”Intelligent styring af dynamisk LED belysning” støttet af EUDP. Arbejdet er udført i perioden 2011‐2012 i samarbejde med Lighten....

Evaluering af afdeling H

DEFF Research Database (Denmark)

Kjær Minke, Linda; Birkmose, Sofie Meldal

2016-01-01

Som led i Kriminalforsorgens flerårsaftale 2013-2016 blev det åbne statsfængsel Søbysøgård i januar 2015 udvidet med 42 lukkede pladser i den nybyggede afdeling H. Nærværende evaluering kortlægger de erfaringer personalet og indsatte har gjort sig i løbet af det første år. Etableringen af den...... lukkede fængselsafdeling H giver en unik mulighed for at følge henholdsvis hvilke faktorer, der bidrager til udvikling af fængselskultur, og hvordan de respektive faktorer influerer på udvikling af fængselskulturen. Evalueringens metoder består af kvalitative og kvantitative metoder såsom dokumentanalyse...

Overførsel af viden ved flytning af produktion

DEFF Research Database (Denmark)

Madsen, Erik Skov; Riis, Jens Ove; Wæhrens, Brian Vejrum

2010-01-01

Empiriske studier i tre industrielle virksomheder har afsløret, at selv virksomheder med mange års erfaring i at overføre produktion til andre lande hovedsagelig fokuserer på planlægning af den fysiske overflytning af produktionsudstyr og fokuserer på den eksplicitte viden, der er tilknyttet prod...

Nitric oxide contamination of hospital compressed air improves gas exchange in patients with acute lung injury.

Science.gov (United States)

Tan, P Seow Koon; Genc, F; Delgado, E; Kellum, J A; Pinsky, M R

2002-08-01

We tested the hypothesis that NO contamination of hospital compressed air also improves PaO(2) in patients with acute lung injury (ALI) and following lung transplant (LTx). Prospective clinical study. Cardiothoracic intensive care unit. Subjects following cardiac surgery (CABG, n=7); with ALI (n=7), and following LTx (n=5). Four sequential 15-min steps at a constant FiO(2) were used: hospital compressed air-O(2) (H1), N(2)-O(2) (A1), repeat compressed air-O(2) (H2), and repeat N(2)-O(2) (A2). NO levels were measured from the endotracheal tube. Cardiorespiratory values included PaO(2) were measured at the end of each step. FiO(2) was 0.46+/-0.05, 0.53+/-0.15, and 0.47+/-0.06 (mean+/-SD) for three groups, respectively. Inhaled NO levels during H1 varied among subjects (30-550 ppb, 27-300 ppb, and 5-220 ppb, respectively). Exhaled NO levels were not detected in 4/7 of CABG (0-300 ppb), 3/6 of ALI (0-140 ppb), and 3/5 of LTx (0-59 ppb) patients during H1, whereas during A1 all but one patient in ALI and three CABG patients had measurable exhaled NO levels (P<0.05). Small but significant decreases in PaO(2) occurred for all groups from H1 to A1 and H2 to A2 (132-99 Torr and 128-120 Torr, P <0.01, respectively). There was no correlation between inhaled NO during H1 and exhaled NO during A1 or the change in PaO(2) from H1 to A1. Low-level NO contamination improves PaO(2) in patients with ALI and following LTx.

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...

The effect of quench rate on the microstructure and properties of AF/C-458 and AF/C-489 Al-Li-Cu-X alloys

Energy Technology Data Exchange (ETDEWEB)

Csontos, A.A.; Gable, B.M.; Starke, E.A. Jr. [Virginia Univ., Charlottesville, VA (United States). Dept. of Mater. Sci. and Eng.; Gaber, A.

2000-07-01

The air force recently developed two isotropic Al-Li-Cu-X alloys with 1.8{sup w}/oLiLi and 2.1{sup w}/oLi designated AF/C-458 and AF/C-489, respectively. The objective of this investigation was to determine the effect of quench rate on the microstructure and mechanical properties of the AF/C-458 and AF/C-489 alloys. TEM, SEM, microhardness, and tensile testing were utilized to ascertain these microstructure/property relationships for both alloys in the T4, T6, and T86 tempers as a function of quench rate. Subsequent losses in ductility for both alloys in all tempers with decreasing quench rate were determined to be due to the precipitation of the equilibrium Al{sub 2}CuLi (T{sub 1}) phase along subgrain and grain boundaries which promoted intergranular fracture. Furthermore, yield and tensile strengths increased for both alloys in the T4 temper but decreased in the T6 and T86 tempers with decreasing quench rate. The increased strengths for the T4 condition resulted from the heterogeneous precipitation of coarse T{sub 1} and naturally aged {delta}' phases. The decrease in yield and tensile strengths for the T6 and T86 tempers were also due to the coarse heterogeneous precipitation of T{sub 1} which denuded regions of Cu thereby reducing the number density of fine matrix {theta}{sup ''} (T6) and T{sub 1} (T86). Finally, a comparison of the quench sensitivity for both the AF/C-458 and AF/C-489 alloys indicates that the mechanical properties for both alloys were less quench rate sensitive than other typical Al-Li-Cu-X alloys. (orig.)

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.

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...

Test af spørgeskema

DEFF Research Database (Denmark)

Hermansen, Jonathan

2017-01-01

Denne bog gennemgår alle surveyarbejdets faser og giver en praktisk indføring i •design af undersøgelsen og udvælgelse af stikprøver, •formulering af spørgeskemaer samt indsamling og kodning af data, •metoder til at analysere resultaterne....

Effects of air jet duration and timing on the combustion characteristics of high-pressure air jet controlled compression ignition combustion mode in a hybrid pneumatic engine

International Nuclear Information System (INIS)

Long, Wuqiang; Meng, Xiangyu; Tian, Jiangping; Tian, Hua; Cui, Jingchen; Feng, Liyan

2016-01-01

Highlights: • A 3-D CFD model of the power cylinder in HPE was developed. • High-pressure air JCCI combustion mode includes two-stage high-temperature reaction. • The combustion phasing of the pre-mixture is controllable via the SOJ timing. • There exists an optimum SOJ timing for obtaining the highest combustion efficiency and shortest burning duration. - Abstract: The high-pressure air jet controlled compression ignition (JCCI) combustion mode was employed to control the premixed diesel compression ignition combustion phasing by using the compound thermodynamic cycle under all operating conditions, which is accomplished in a hybrid pneumatic engine (HPE). A three-dimensional computational fluid dynamics (CFD) numerical simulation coupled with reduced n-heptane chemical kinetics mechanism has been applied to investigate the effects of high-pressure air jet duration and the start of jet (SOJ) timing on the combustion characteristics in the power cylinder of HPE. By sweeping the high-pressure air jet durations from 6 to 14 °CA and SOJ timings from −12 °CA ATDC to the top dead center (TDC) under the air jet temperatures of 400 and 500 K, respectively, the low- and high-temperature reactions, combustion efficiency, as well as the combustion phasing and burning duration have been analyzed in detail. The results illustrated that a longer air jet duration results in a higher peak in the first-stage high-temperature reaction, and the short air jet duration of 6 °CA can lead to a higher combustion efficiency. The SOJ timing sweep results showed that there exists an optimum timing for obtaining the highest combustion efficiency and shortest burning duration.

Test af to versioner af Modflow-LGR til simulering af grundvandsstrømninger i områder med begravede dale – syntetisk studie

DEFF Research Database (Denmark)

Vilhelmsen, Troels Norvin; Christensen, Steen

.eks. findes i begravede dale. Manglende opløsning af geologiske aflejringer på lokal skala kan potentielt resultere i fejlagtige prædiktioner af konsekvensen af grundvandsindvinding på kildeplads niveau. For i højere grad at kunne forvalte disse grundvandsressourcerne skal nye metoder undersøges. Dette er...... specielt gældende for komplekse begravede dalsystemer, som interagerer med omkringliggende regionale grundvandsystemer. I dette syntetiske studie er to versioner af MODFLOW - Local Grid Refinment (LGR) testet til simulering af grundvandsstrømninger i områder med begravede dale. Forsøgene er gennemført som...

Professor: Lær af Canada

DEFF Research Database (Denmark)

Greve, Carsten

2013-01-01

Transportdebatten: En mulig finansiering af fremtidige infrastrukturprojekter kunne være OPP. Danmark bør tage ved lære af erfaringer fra Canada.......Transportdebatten: En mulig finansiering af fremtidige infrastrukturprojekter kunne være OPP. Danmark bør tage ved lære af erfaringer fra Canada....

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...

Performance of a Compression-ignition Engine with a Precombustion Chamber Having High-Velocity Air Flow

Science.gov (United States)

Spanogle, J A; Moore, C S

1931-01-01

Presented here are the results of performance tests made with a single-cylinder, four stroke cycle, compression-ignition engine. These tests were made on a precombustion chamber type of cylinder head designed to have air velocity and tangential air flow in both the chamber and cylinder. The performance was investigated for variable load and engine speed, type of fuel spray, valve opening pressure, injection period and, for the spherical chamber, position of the injection spray relative to the air flow. The pressure variations between the pear-shaped precombustion chamber and the cylinder for motoring and full load conditions were determined with a Farnboro electric indicator. The combustion chamber designs tested gave good mixing of a single compact fuel spray with the air, but did not control the ensuing combustion sufficiently. Relative to each other, the velocity of air flow was too high, the spray dispersion by injection too great, and the metering effect of the cylinder head passage insufficient. The correct relation of these factors is of the utmost importance for engine performance.

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....

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.

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.

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...

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...

Modelling study, efficiency analysis and optimisation of large-scale Adiabatic Compressed Air Energy Storage systems with low-temperature thermal storage

International Nuclear Information System (INIS)

Luo, Xing; Wang, Jihong; Krupke, Christopher; Wang, Yue; Sheng, Yong; Li, Jian; Xu, Yujie; Wang, Dan; Miao, Shihong; Chen, Haisheng

2016-01-01

Highlights: • The paper presents an A-CAES system thermodynamic model with low temperature thermal energy storage integration. • The initial parameter value ranges for A-CAES system simulation are identified from the study of a CAES plant in operation. • The strategies of system efficiency improvement are investigated via a parametric study with a sensitivity analysis. • Various system configurations are discussed for analysing the efficiency improvement potentials. - Abstract: The key feature of Adiabatic Compressed Air Energy Storage (A-CAES) is the reuse of the heat generated from the air compression process at the stage of air expansion. This increases the complexity of the whole system since the heat exchange and thermal storage units must have the capacities and performance to match the air compression/expansion units. Thus it raises a strong demand in the whole system modelling and simulation tool for A-CAES system optimisation. The paper presents a new whole system mathematical model for A-CAES with simulation implementation and the model is developed with consideration of lowing capital cost of the system. The paper then focuses on the study of system efficiency improvement strategies via parametric analysis and system structure optimisation. The paper investigates how the system efficiency is affected by the system component performance and parameters. From the study, the key parameters are identified, which give dominant influences in improving the system efficiency. The study is extended onto optimal system configuration and the recommendations are made for achieving higher efficiency, which provides a useful guidance for A-CAES system design.

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...

Hvad griner du af?

DEFF Research Database (Denmark)

Lorenzen, Tobias Hiort

2012-01-01

latterliggørelse indenfor en sådan teori. Sociologiens begreb om ”un-laughter” angives som en mulig udvej af dette problem. I forlængelse af dette kritiseres den moderne humor-psykologis lære om populationers humor-patologi og til slut argumenteres der for at en moderne dannelse af humor må have en moralsk...

Free compression tube. Applications

Science.gov (United States)

Rusu, Ioan

2012-11-01

During the flight of vehicles, their propulsion energy must overcome gravity, to ensure the displacement of air masses on vehicle trajectory, to cover both energy losses from the friction between a solid surface and the air and also the kinetic energy of reflected air masses due to the impact with the flying vehicle. The flight optimization by increasing speed and reducing fuel consumption has directed research in the aerodynamics field. The flying vehicles shapes obtained through studies in the wind tunnel provide the optimization of the impact with the air masses and the airflow along the vehicle. By energy balance studies for vehicles in flight, the author Ioan Rusu directed his research in reducing the energy lost at vehicle impact with air masses. In this respect as compared to classical solutions for building flight vehicles aerodynamic surfaces which reduce the impact and friction with air masses, Ioan Rusu has invented a device which he named free compression tube for rockets, registered with the State Office for Inventions and Trademarks of Romania, OSIM, deposit f 2011 0352. Mounted in front of flight vehicles it eliminates significantly the impact and friction of air masses with the vehicle solid. The air masses come into contact with the air inside the free compression tube and the air-solid friction is eliminated and replaced by air to air friction.

Adiabatic Compressed Air Energy Storage with packed bed thermal energy storage

International Nuclear Information System (INIS)

Barbour, Edward; Mignard, Dimitri; Ding, Yulong; Li, Yongliang

2015-01-01

Highlights: • The paper presents a thermodynamic analysis of A-CAES using packed bed regenerators. • The packed beds are used to store the compression heat. • A numerical model is developed, validated and used to simulate system operation. • The simulated efficiencies are between 70.5% and 71.1% for continuous operation. • Heat build-up in the beds reduces continuous cycle efficiency slightly. - Abstract: The majority of articles on Adiabatic Compressed Air Energy Storage (A-CAES) so far have focussed on the use of indirect-contact heat exchangers and a thermal fluid in which to store the compression heat. While packed beds have been suggested, a detailed analysis of A-CAES with packed beds is lacking in the available literature. This paper presents such an analysis. We develop a numerical model of an A-CAES system with packed beds and validate it against analytical solutions. Our results suggest that an efficiency in excess of 70% should be achievable, which is higher than many of the previous estimates for A-CAES systems using indirect-contact heat exchangers. We carry out an exergy analysis for a single charge–storage–discharge cycle to see where the main losses are likely to transpire and we find that the main losses occur in the compressors and expanders (accounting for nearly 20% of the work input) rather than in the packed beds. The system is then simulated for continuous cycling and it is found that the build-up of leftover heat from previous cycles in the packed beds results in higher steady state temperature profiles of the packed beds. This leads to a small reduction (<0.5%) in efficiency for continuous operation

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.

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...

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...

A low-cost hybrid drivetrain concept based on compressed air energy storage

International Nuclear Information System (INIS)

Brown, T.L.; Atluri, V.P.; Schmiedeler, J.P.

2014-01-01

Highlights: • A new pneumatic hybrid concept is introduced. • A proof-of-concept prototype system is built and tested. • The experimental system has a round-trip efficiency of just under 10%. • A thermodynamics model is used to predict the performance of modified designs. • An efficiency of nearly 50% is possible with reasonable design changes. - Abstract: This paper introduces a new low-cost hybrid drivetrain concept based on compressed air energy storage. In contrast to most contemporary approaches to pneumatic hybridization, which require modification to the primary power plant, this concept is based on a stand-alone pneumatic system that could be readily integrated with existing vehicles. The pneumatic system consists of an air tank and a compressor–expander that is coupled to the rest of the drivetrain via an infinitely variable transmission. Rather than incorporating more expensive technologies such as variable valve timing or a variable compression ratio compressor, a fixed valve system consisting of a rotary valve and passive check valves is optimized to operate efficiently over a range of tank pressures. The feasibility of this approach is established by thermodynamic modeling and the construction of a proof-of-concept prototype, which is also used to fine tune model parameters. While the proof-of-concept system shows a round trip efficiency of just under 10%, modeling shows that a round trip efficiency of 26% is possible with a revised design. If waste heat from the engine is used to maintain an elevated tank temperature, efficiencies of nearly 50% may be possible, indicating that the concept could be effective for practical hybridization of passenger vehicles

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.  ...

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...

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...

Strategisk ledelse af evalueringskulturen

Directory of Open Access Journals (Sweden)

Gitte Orlowitz

2016-02-01

Full Text Available Hvis evaluering skal anvendes til at udvikle uddannelser, er en af ledelsen vigtigste opgaver at udvikle en strategi for udvikling af evalueringskulturen – herunder strategier for udvikling af kommunikation og evalueringskapacitet. Den strategiske ledelse kan i den sammenhæng anvendes til at håndtere de ofte modsatte krav, som eksterne og interne interessenter stiller til evaluering.

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.

Trans-anal barotrauma by compressed air leading to sigmoid perforation due to a dangerous practical joke.

Science.gov (United States)

Pahwa, Harvinder Singh; Kumar, Awanish; Srivastava, Rohit; Rai, Anurag

2012-08-01

To present a case report of trans-anal barotrauma by high-pressure compressed air jet as a dangerous practical joke, that is, playful insufflation of high-pressure air jet through the anal orifice resulting in sigmoid perforation. The patient presented to emergency a day later with complaints of severe pain in the abdomen and abdominal distension following insufflation of high-pressure air jet through the anus. On examination, he had signs suggestive of perforation peritonitis and x-ray of the abdomen showed gas under the diaphragm. An emergency exploratory laparotomy was performed which revealed a 4-cm perforation in the sigmoid colon. Resection of the segment containing perforation along with the surrounding devitalised part was done with double-barrel colostomy. Reversal of colostomy was done after 8 weeks. Follow-up was uneventful.

Prediction of the thermohydraulic performance of porous-media reservoirs for compressed-air energy storage

Energy Technology Data Exchange (ETDEWEB)

Wiles, L.E.; McCann, R.A.

1981-09-01

The numerical modeling capability that has been developed at the Pacific Northwest Laboratory (PNL) for the prediction of the thermohydraulic performance of porous media reservoirs for compressed air energy storage (CAES) is described. The capability of the numerical models was demonstrated by application to a variety of parametric analyses and the support analyses for the CAES porous media field demonstration program. The demonstration site analyses include calculations for the displacement of aquifer water to develop the air storage zone, the potential for water coning, thermal development in the reservoir, and the dehydration of the near-wellbore region. Unique features of the demonstration site reservoir that affect the thermohydraulic performance are identified and contrasted against the predicted performance for conditions that would be considered more typical of a commercial CAES site.

Evaluering af FIU`s akademiuddannelser

DEFF Research Database (Denmark)

Hansen, Agnete Meldgaard; Nielsen, Kurt Aagaard

I rapporten præsenteres en empirisk evaluerinf af to nye uddannelser i FIUs regi. I forlængelse af evalueringen præsenteres en forskningsmæssig analyse a uddannelsernes rolle i fagbevægelsens modernisering......I rapporten præsenteres en empirisk evaluerinf af to nye uddannelser i FIUs regi. I forlængelse af evalueringen præsenteres en forskningsmæssig analyse a uddannelsernes rolle i fagbevægelsens modernisering...

Compressed gas fuel storage system

Science.gov (United States)

Wozniak, John J.; Tiller, Dale B.; Wienhold, Paul D.; Hildebrand, Richard J.

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.

A soft compressive sensor using dielectric elastomers

International Nuclear Information System (INIS)

Zhang, Hongying; Wang, Michael Yu; Li, Jisen; Zhu, Jian

2016-01-01

This paper proposes a methodology to design, analyze and fabricate a soft compressive sensor, made of dielectric elastomers that are able to recover from large strain. Each module of the compressive sensor is modeled as a capacitor, comprising a DE membrane sandwiched between two compliant electrodes. When the sensor modules aligned in an array were subject to a compressive load, the induced deformation on the corresponding module resulted in capacitance increase. By detecting the capacitance signal, not only the position but also the magnitude of the compressive load were obtained. We built an analytical model to simulate the mechanical–electrical responses of two common soft sensor structures, namely with and without an embedded air chamber. The simulation results showed that the air embedded prototype improved the sensitivity of the sensor significantly, which was consistent with the experimental results, where the sensitivity is enhanced from 0.05 N −1 to 0.91 N −1 . Furthermore, the effect of the air chamber dimension on the sensitivity is also discussed theoretically and experimentally. It concluded that the detection range increased with the air chamber height over length ratio. (paper)

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...

Humidity-dependent compression-induced glass transition of the air-water interfacial Langmuir films of poly(D,L-lactic acid-ran-glycolic acid) (PLGA).

Science.gov (United States)

Kim, Hyun Chang; Lee, Hoyoung; Jung, Hyunjung; Choi, Yun Hwa; Meron, Mati; Lin, Binhua; Bang, Joona; Won, You-Yeon

2015-07-28

Constant rate compression isotherms of the air-water interfacial Langmuir films of poly(D,L-lactic acid-ran-glycolic acid) (PLGA) show a distinct feature of an exponential increase in surface pressure in the high surface polymer concentration regime. We have previously demonstrated that this abrupt increase in surface pressure is linked to the glass transition of the polymer film, but the detailed mechanism of this process is not fully understood. In order to obtain a molecular-level understanding of this behavior, we performed extensive characterizations of the surface mechanical, structural and rheological properties of Langmuir PLGA films at the air-water interface, using combined experimental techniques including the Langmuir film balance, X-ray reflectivity and double-wall-ring interfacial rheometry methods. We observed that the mechanical and structural responses of the Langmuir PLGA films are significantly dependent on the rate of film compression; the glass transition was induced in the PLGA film only at fast compression rates. Surprisingly, we found that this deformation rate dependence is also dependent on the humidity of the environment. With water acting as a plasticizer for the PLGA material, the diffusion of water molecules through the PLGA film seems to be the key factor in the determination of the glass transformation properties and thus the mechanical response of the PLGA film against lateral compression. Based on our combined results, we hypothesize the following mechanism for the compression-induced glass transformation of the Langmuir PLGA film; (1) initially, a humidified/non-glassy PLGA film is formed in the full surface-coverage region (where the surface pressure shows a plateau) during compression; (2) further compression leads to the collapse of the PLGA chains and the formation of new surfaces on the air side of the film, and this newly formed top layer of the PLGA film is transiently glassy in character because the water evaporation rate

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...

Dansk oversættelse af MiDAS, et redskab til assessment af musikterapi for personer med demens

DEFF Research Database (Denmark)

Ridder, Hanne Mette Ochsner; Lykkegaard, Chris; McDermott, Orii

2018-01-01

Music in Dementia Assessment Scales, MiDAS, er udviklet til at vurdere ændringer i trivsel hos borgere med demens som har deltaget i musikterapi. Målingen udføres af 1) personale før og efter musikterapien for at vurdere om der er en indflydelse i hverdagssituationer efterfølgende, eller af 2......) musikterapeuten umiddelbart efter sessionen for at vurdere forandringer i selve sessionen. Der har været stor interesse for at anvende MiDAS i flere Europæiske lande, herunder Danmark. Derfor undersøgte udviklerne af MiDAS hvilke procedurer der anvendes til oversættelse og kulturel tilpasning af...... assessmentredskaber, og anbefalede på den baggrund en ti-trins procedure. Vi anvendte denne procedure til oversættelsen af MiDAS og således udviklingen af den danske MiDAS-DK. Den danske version af MiDAS er afprøvet af mere end 20 fagpersoner på baggrund af 296 udfyldte MiDAS-skemaer. Målet med artiklen er...

Fremtidens biblioteksbetjening af børn

DEFF Research Database (Denmark)

Høyrup, Helene

2008-01-01

Rapporten er resultatet af et tværministerielt udvalgsarbejde nedsat af Kulturministeriet.  Kommissoriet har været at nytænke biblioteksbetjeningen af børn, så den passer til vidensamfundet.  Udvalgsarbejdet munder ud i ti bud for fremtidens biblioteksbetjening af børn....

Beregning af luftlydisolation mellem to rum

DEFF Research Database (Denmark)

Donovan, A.

Meddelelsen bringer resultaterne af en forundersøgelse af to beregningsmetoder. Den ene metode belyses nærmere gennem nogle forenklede eksempler, der viser omfanget af regnearbejdet og peger på nogle af de vanskeligheder det vil indebære at opstille en praktisk anvendelig beregningsmetode....

Regulering af det psykiske arbejdsmiljø

DEFF Research Database (Denmark)

Nielsen, Klaus T.

nationale informationer om reguleringen af det psykiske arbejdsmiljø. Rapport er bygget op med ◊ et internationalt overblik over regulering af psykisk arbejdsmiljø ◊ en bredere diskussion af reguleringens dilemmaer ◊ en gennemgang af den aktuelle danske udvikling ◊ udfordringerne på området...

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...

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...

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...

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...

Economic analysis of using above ground gas storage devices for compressed air energy storage system

Science.gov (United States)

Liu, Jinchao; Zhang, Xinjing; Xu, Yujie; Chen, Zongyan; Chen, Haisheng; Tan, Chunqing

2014-12-01

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.

Anvendelse af koldpresset rapsolie på varebiler

DEFF Research Database (Denmark)

Nielsen, Claus Suldrup; Ivarsson, Anders; Schramm, Jesper

Denne rapport sammenfatter resultaterne af undersøgelserne omkring anvendelse af koldpresset rapsolie på varebiler. Undersøgelsen, som er udført af Danmarks Tekniske Universitet, Institut for Mekanisk Teknologi, er en del af et større projekt, som er finansieret af Trafikstyrelsens (tidligere Fær...... Færdselsstyrelsen) tilskudsordning til forsøg med biodiesel. Projektet har været administreret af Odense Kommune....

Studerende og underviseres brug af digitale medier - En kvantitativ undersøgelse af Aarhus Universitets studerende og underviseres brug af digitale medier og internettet anno 2008

Directory of Open Access Journals (Sweden)

Maria Hvid Stenalt

2009-06-01

• Hvilke medier anvender universitetsstuderende generelt? • Ligner undervisernes medievalg/forbrug de studerendes? • Hvilke medier inddrager underviserne i undervisningen? Nærværende artikel vil forsøge at besvare disse spørgsmål på baggrund af en kvantitativ spørgeskemaundersøgelse af Aarhus Universitets studerende og underviseres brug af digitale medier og internettet. Undersøgelsen blev gennemført i efteråret 2008 af E-læringsenheden ved Aarhus Universitet som led i en almen kvalitetssikring på media- og e-læringsområdet, samt som led i en behovsafklaring vedrørende etablering af et medie- og podcastarkiv. E-læringsenheden er en administrativ enhed, der teknisk og pædagogisk understøtter underviseres inddragelse af digitale medier i undervisningen.

Introduction of a compressed air breathing apparatus for the offshore oil and gas industry.

Science.gov (United States)

Brooks, Chris J; MacDonald, Conor V; Carroll, Joel; Gibbs, Peter N G

2010-07-01

When a helicopter ditches the majority of crew and passengers have to make an underwater escape. Some may not be able to hold their breath and will drown. For at least 15 yr, military aircrew have been trained to use a scuba system. In the offshore oil and gas industry, there has been more caution about introducing a compressed air system and a rebreather system has been introduced as an alternative. Recently, Canadian industry and authorities approved the introduction of Helicopter Underwater Emergency Breathing Apparatus (HUEBA) training using compressed air. This communication reports the training of the first 1000 personnel. Training was introduced in both Nova Scotia and Newfoundland concurrently by the same group of instructors. Trainees filled out a questionnaire concerning their perceived ratings of the ease or difficulty of classroom training and the practical use of the HUEBA. Ninety-eight percent of trainees found the classroom and in-water training to be "good/very good". Trainees found it to be "easy/very easy" to clear the HUEBA and breathe underwater in 84% and 64% of cases, respectively. Divers reported a greater ease in learning all the practical uses of the HUEBA except application of the nose clip. There were problems with the nose clip fitting incorrectly, and interference of the survival suit hood with the regulator, which subsequently have been resolved. When carefully applied, the introduction of the HUEBA into training for offshore oil and gas industry helicopter crew and passengers can be safely conducted.

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...

Global opvarmning neutraliserer effekten af parasitisme på strandsnegles konsumption af makroalger

DEFF Research Database (Denmark)

Larsen, Martin H.; Mouritsen, Kim Nørgaard

Det er veldokumenteret, at parasitter kan påvirke værternes adfærd, overlevelse, reproduktion, fysiologi og evolution. Disse parasit-vært interaktioner kan føre til radikale ændringer af naturlige samfunds struktur og diversitet. Eksperimenter har eksempelvis vist, at trematoder indirekte kan ændre...... 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...

Feasibility study of a hybrid wind turbine system – Integration with compressed air energy storage

International Nuclear Information System (INIS)

Sun, Hao; Luo, Xing; Wang, Jihong

2015-01-01

Highlights: • A new hybrid wind turbine system is proposed and feasibility study if conducted. • A complete mathematical model is developed and implemented in a software environment. • Multi-mode control strategy is investigated to ensure the system work smoothly and efficiently. • A prototype for implementing the proposed mechanism is built and tested as proof of the concept. • The proposed system is proved to be technically feasible with energy efficiency around 50%. - Abstract: 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 storage. A mechanical transmission mechanism is designed and implemented for power integration within the hybrid system. A scroll expander is adopted to serve as an “air-machinery energy converter”, which can transmit additional driving power generalized from the stored compressed air to the turbine shaft for smoothing the wind power fluctuation. A mathematical model for the complete hybrid process is developed and the control strategy is investigated for corresponding cooperative operations. A prototype test rig for implementing the proposed mechanism is built for proof of the concept. From the simulated and experimental studies, the energy conversion efficiency analysis is conducted while the system experiences different operation conditions and modes. It is proved that the proposed hybrid wind turbine system is feasible technically

Måling af stress hos mink

DEFF Research Database (Denmark)

Malmkvist, Jens

2010-01-01

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...... 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....

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...

Påvisning af PCV2

DEFF Research Database (Denmark)

Neumann, Katrine; Buse, Katja Strøm; Hjulsager, Charlotte Kristiane

2018-01-01

Mængden af PCV2-virus i poolede serumprøver kan anvendes til at finde grise med meget PCV2-virus, hvorimod mængden af PCV2-virus i spyt og fæces er velegnede til at vurdere tilstedeværelsen af eller tidspunktet for en begyndende PCV2-infektion...

Påvisning af PCV2

DEFF Research Database (Denmark)

Neumann, Katrine; Buse, Katja Strøm; Hjulsager, Charlotte Kristiane

Mængden af PCV2-virus i poolede serumprøver kan anvendes til at finde grise med meget PCV2-virus, hvorimod mængden af PCV2-virus i spyt og fæces er velegnede til at vurdere tilstedeværelsen af eller tidspunktet for en begyndende PCV2-infektion...

Topological ferrimagnetic behaviours of coordination polymers containing manganese(II) chains with mixed azide and carboxylate bridges and alternating F/AF/AF'/AF'/AF interactions.

Science.gov (United States)

Wang, Yan-Qin; Liu, Hou-Ting; Qi, Yan; Gao, En-Qing

2014-08-21

Two Mn(ii) complexes with azide and a new zwitterionic tetracarboxylate ligand 1,2,4,5-tetrakis(4-carboxylatopyridinium-1-methylene)benzene (L(1)), {[Mn5(L(1))2(N3)8(OH)2]·12H2O}n () and {[Mn5(L(1))2(N3)8(H2O)2](ClO4)2·6H2O}n (), have been synthesized and characterized crystallographically and magnetically. and contain similar alternating chains constructed by azide and carboxylate bridges. The independent sets of bridges alternate in an ABCCB sequence between adjacent Mn(ii) ions: (EO-N3)2 double bridges (EO = end-on) (denoted as A), [(EO-N3)(OCO)2] triple bridges (denoted as B) and [(EO-N3)(OCO)] double bridges (denoted as C). The alternating chains are interlinked into 2D coordination networks by the tetrapyridinium spacers. Magnetic studies demonstrate that the magnetic coupling through the double EO azide bridges is ferromagnetic and that through mixed azide/carboxylate bridges is antiferromagnetic. The unprecedented F/AF/AF'/AF'/AF coupling sequence along the chain dictates an uncompensated ground spin state (S = 5/2 per Mn5 unit) and leads to one-dimensional topological ferrimagnetism, which features a minimum in the χT versus T plot.

Health Information in Somali (Af-Soomaali )

Science.gov (United States)

... and Wound Healing - Af-Soomaali (Somali) Bilingual PDF Health Information Translations Fasting Blood Sugar Test - Af-Soomaali (Somali) Bilingual PDF Health Information Translations GTT (Glucose Tolerance Test) - Af-Soomaali ( ...

Barrierer for ibrugtagning af videooptaget universitetsundervisning

DEFF Research Database (Denmark)

Rattleff, Pernille

2009-01-01

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...... 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...

Air Force Senior Leaders

Science.gov (United States)

Force TV Radio Week in Photos About Us Air Force Senior Leaders SECAF CSAF CMSAF Biographies Adjunct Professors Senior Mentor Biographies Fact Sheets Commander's Call Topics CCT Archive CSAF Reading List 2017 Media Sites Site Registration Contact Us Search AF.mil: Home > About Us > Air Force Senior Leaders

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"...

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)

Strategi til udbredelse og udvikling af aquaponik

OpenAIRE

Bartholin, Aline; Nielsen, Per

2014-01-01

Denne rapport omhandler, hvorledes aquaponik i fremtiden skal udbredes med henblik på at produktionsmetoden bliver en del af den etablerede fødevaresektor. Ud fra et interview med PlanteLaboratoriet som er en del af foreningen Akvaponisk Selskab, samt observationer af en workshop afholdt af PlanteLaboratoriet forsøger vi at kortlægge den førte strategi til udbredelse og udvikling af aquaponik, samt undersøge hvorledes aquaponik som innovation bliver taget imod af mulige adoptere. Empirien sam...

Bekæmpelse af elmesyge

DEFF Research Database (Denmark)

Thomsen, Iben Margrete; Kristoffersen, Palle; Ravn, Hans Peter

2004-01-01

Elmesygen kom til Danmark i 1970’erne. Efter 1985 er udbredelsen gået stærkt, og elmesygen har været katastrofal for bestanden af bytræer og træer i landskabet. Bekæmpelse består fortrinsvis af sanering, dvs. fjernelse af syge og billeangrebne træer inden 1. maj....

Energiforbrug til opvarmning af bygninger

DEFF Research Database (Denmark)

Budde, J.; Pedersen, D.O.

Rapporten giver oplysninger om enhedsforbrug til varme og varmt brugsvand i forskellige typer af bygninger baseret på en analyse af et omfattende datamateriale. Formålet med undersøgelsen har været at ajourføre denne del af grundlaget for både landsdækkende og lokal varmeplanlægning i Danmark....

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 ...

Dannelsen af den ansvarlige elev

DEFF Research Database (Denmark)

Larsen, Jesper

2010-01-01

Denne artikel handler om den del af lærergerningen, der har at gøre med udarbejdelse af elevplaner. Der tages udgangspunkt i en foucaultsk forståelse, hvor beskrivelsen af den enkelte elev udtrykker et særligt normativt ideal om, hvilke former for elevhed der er de ønskværdige i den danske...

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...... funktionalitet som en del af undervisningen. Det er afgørende at teknologien er pålidelig og er let at gå til, da det er kernefunktionen i denne type af spil. Legens rolle er vigtig for motivationen, men må ikke overtage de formelle krav til den undervisning, som spillet er del af. Det var entydigt omkring...

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...

A multiphase compressible model for the simulation of multiphase flows

International Nuclear Information System (INIS)

Caltagirone, J.P.; Vincent, St.; Caruyer, C.

2011-01-01

A compressible model able to manage incompressible two-phase flows as well as compressible motions is proposed. After a presentation of the multiphase compressible concept, the new model and related numerical methods are detailed on fixed structured grids. The presented model is a 1-fluid model with a reformulated mass conservation equation which takes into account the effects of compressibility. The coupling between pressure and flow velocity is ensured by introducing mass conservation terms in the momentum and energy equations. The numerical model is then validated with four test cases involving the compression of an air bubble by water, the liquid injection in a closed cavity filled with air, a bubble subjected to an ultrasound field and finally the oscillations of a deformed air bubble in melted steel. The numerical results are compared with analytical results and convergence orders in space are provided. (authors)

Compressive Creep Behavior of NEXTEL(TradeMark) 720/Alumina Ceramic Matrix Composite at 1200 Degrees C in Air and in Steam Environment

National Research Council Canada - National Science Library

Szymczak, Neil R

2006-01-01

...) 720/Alumina ceramic matrix composite at 1200 deg. C in air and 100% steam environments. The effects of creep loading history on the tensile and compressive material behavior will also be examined...

På sporet af innovation

DEFF Research Database (Denmark)

Strandgaard, Lone Bak

organisationen blandt ledere og medarbejdere samt eksternt, uden for organisationen, hos dens kunder. Ph.d.-afhandlingen På sporet af innovation har som formål at bidrage til forståelse af, hvordan organisationers arbejde med digital selvbetjening kan fremmes, set i et innovationsteoretisk perspektiv. Foruden en...... indføring i innovationsteorien og dens udvikling belyser afhandlingens resultater hvordan at innovationspotentialet kan styrkes gennem organisatorisk åbenhed og samarbejde i alle dele af den innovative proces. Dette gælder ved både idéudvikling, realisering og spredning af nye digitale løsninger.......Flere og flere private og offentlige servicer digitaliseres, så kunder, borgere og virksomheder, i øget grad betjener sig selv. Digital selvbetjening kan potentielt effektivisere driften og skabe bedre kundeservice. Men processen har udfordringer, da den kan kræve omfattende omstilling internt i...

Dansk oversættelse af MiDAS, et redskab til assessment af musikterapi for personer med demens

DEFF Research Database (Denmark)

Ridder, Hanne Mette Ochsner; Lykkegaard, Chris; McDermott, Orii

2018-01-01

DAS explored which procedures is used for outcome measure translation and cultural adaptation, and based on this recommended a ten-step procedure. We applied this procedure in order to translate MiDAS and hereby develop the Danish MiDAS-DK. The Danish MiDAS version has been tested by more than 20 professionals......) musikterapeuten umiddelbart efter sessionen for at vurdere forandringer i selve sessionen. Der har været stor interesse for at anvende MiDAS i flere Europæiske lande, herunder Danmark. Derfor undersøgte udviklerne af MiDAS hvilke procedurer der anvendes til oversættelse og kulturel tilpasning af...... assessmentredskaber, og anbefalede på den baggrund en ti-trins procedure. Vi anvendte denne procedure til oversættelsen af MiDAS og således udviklingen af den danske MiDAS-DK. Den danske version af MiDAS er afprøvet af mere end 20 fagpersoner på baggrund af 296 udfyldte MiDAS-skemaer. Målet med artiklen er...

Thermo-fluid dynamic analysis of wet compression process

Energy Technology Data Exchange (ETDEWEB)

Mohan, Abhay; Kim, Heuy Dong [School of Mechanical Engineering, Andong National University, Andong (Korea, Republic of); Chidambaram, Palani Kumar [FMTRC, Daejoo Machinery Co. Ltd., Daegu (Korea, Republic of); Suryan, Abhilash [Dept. of Mechanical Engineering, College of Engineering Trivandrum, Kerala (India)

2016-12-15

Wet compression systems increase the useful power output of a gas turbine by reducing the compressor work through the reduction of air temperature inside the compressor. The actual wet compression process differs from the conventional single phase compression process due to the presence of latent heat component being absorbed by the evaporating water droplets. Thus the wet compression process cannot be assumed isentropic. In the current investigation, the gas-liquid two phase has been modeled as air containing dispersed water droplets inside a simple cylinder-piston system. The piston moves in the axial direction inside the cylinder to achieve wet compression. Effects on the thermodynamic properties such as temperature, pressure and relative humidity are investigated in detail for different parameters such as compression speeds and overspray. An analytical model is derived and the requisite thermodynamic curves are generated. The deviations of generated thermodynamic curves from the dry isentropic curves (PV{sup γ} = constant) are analyzed.

Thermo-fluid dynamic analysis of wet compression process

International Nuclear Information System (INIS)

Mohan, Abhay; Kim, Heuy Dong; Chidambaram, Palani Kumar; Suryan, Abhilash

2016-01-01

Wet compression systems increase the useful power output of a gas turbine by reducing the compressor work through the reduction of air temperature inside the compressor. The actual wet compression process differs from the conventional single phase compression process due to the presence of latent heat component being absorbed by the evaporating water droplets. Thus the wet compression process cannot be assumed isentropic. In the current investigation, the gas-liquid two phase has been modeled as air containing dispersed water droplets inside a simple cylinder-piston system. The piston moves in the axial direction inside the cylinder to achieve wet compression. Effects on the thermodynamic properties such as temperature, pressure and relative humidity are investigated in detail for different parameters such as compression speeds and overspray. An analytical model is derived and the requisite thermodynamic curves are generated. The deviations of generated thermodynamic curves from the dry isentropic curves (PV γ = constant) are analyzed

MR-AFS: a global hierarchical file-system

International Nuclear Information System (INIS)

Reuter, H.

2000-01-01

The next generation of fusion experiments will use object-oriented technology creating the need for world wide sharing of an underlying hierarchical file-system. The Andrew file system (AFS) is a well known and widely spread global distributed file-system. Multiple-resident-AFS (MR-AFS) combines the features of AFS with hierarchical storage management systems. Files in MR-AFS therefore may be migrated on secondary storage, such as roboted tape libraries. MR-AFS is in use at IPP for the current experiments and data originating from super-computer applications. Experiences and scalability issues are discussed

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...

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....

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...

Does an interdisciplinary outpatient atrial fibrillation (AF) clinic affect the number of acute AF admissions?

DEFF Research Database (Denmark)

Frydensberg, Vivi Skibdal; Brandes, Axel

2018-01-01

AIMS AND OBJECTIVES: To investigate the impact of a multidisciplinary outpatient clinic for patients with atrial fibrillation (AF-clinic) on the number of acute hospitalizations for atrial fibrillation compared with usual outpatient care for this condition before the establishment of the AF-clinic....... BACKGROUND: Guidelines recommend a structured outpatient clinic follow-up in multidisciplinary teams for patients with atrial fibrillation due to fewer hospitalizations and death. However the evidence base is weak. DESIGN: The study is a retrospective cohort study including a total of 129 patients from...... the cardiac outpatient clinic at a large Danish University Hospital. The study population consisted of two groups: a usual care group before a dedicated AF-clinic was established (n=73) and the AF-clinic group (n=56). The primary endpoint was acute hospitalization for AF. METHODS: Cox regression was used...

Development of a Next-Generation Membrane-Integrated Adsorption Processor for CO2 Removal and Compression for Closed-Loop Air Revitalization Systems

Science.gov (United States)

Mulloth, Lila; LeVan, Douglas

2002-01-01

The current CO2 removal technology of NASA is very energy intensive and contains many non-optimized subsystems. This paper discusses the concept of a next-generation, membrane integrated, adsorption processor for CO2 removal nd compression in closed-loop air revitalization systems. This processor will use many times less power than NASA's current CO2 removal technology and will be capable of maintaining a lower CO2 concentration in the cabin than that can be achieved by the existing CO2 removal systems. The compact, consolidated, configuration of gas dryer, CO2 separator, and CO2 compressor will allow continuous recycling of humid air in the cabin and supply of compressed CO2 to the reduction unit for oxygen recovery. The device has potential application to the International Space Station and future, long duration, transit, and planetary missions.

Reduced injection pressures using a compressed air injection technique (CAIT): an in vitro study.

Science.gov (United States)

Tsui, Ban C H; Knezevich, Mark P; Pillay, Jennifer J

2008-01-01

High injection pressures have been associated with intraneural injection and persistent neurological injury in animals. Our objective was to test whether a reported simple compressed air injection technique (CAIT) would limit the generation of injection pressures to below a suggested 1,034 mm Hg limit in an in vitro model. After ethics board approval, 30 consenting anesthesiologists injected saline into a semiclosed system. Injection pressures using 30 mL syringes connected to a 22 gauge needle and containing 20 mL of saline were measured for 60 seconds using: (1) a typical "syringe feel" method, and (2) CAIT, thereby drawing 10 mL of air above the saline and compressing this to 5 mL prior to and during injections. All anesthesiologists performed the syringe feel method before introduction and demonstration of CAIT. Using CAIT, no anesthesiologist generated pressures above 1,034 mm Hg, while 29 of 30 produced pressures above this limit at some time using the syringe feel method. The mean pressure using CAIT was lower (636 +/- 71 vs. 1378 +/- 194 mm Hg, P = .025), and the syringe feel method resulted in higher peak pressures (1,875 +/- 206 vs. 715 +/- 104 mm Hg, P = .000). This study demonstrated that CAIT can effectively keep injection pressures under 1,034 mm Hg in this in vitro model. Animal and clinical studies will be needed to determine whether CAIT will allow objective, real-time pressure monitoring. If high pressure injections are proven to contribute to nerve injury in humans, this technique may have the potential to improve the safety of peripheral nerve blocks.

Structural analysis of porous rock reservoirs subjected to conditions of compressed air energy storage

Energy Technology Data Exchange (ETDEWEB)

Friley, J.R.

1980-01-01

Investigations are described which were performed to assess the structural behavior of porous rock compressed air energy storage (CAES) reservoirs subjected to loading conditions of temperature and pressure felt to be typical of such an operation. Analyses performed addressed not only the nominal or mean reservoir response but also the cyclic response due to charge/discharge operation. The analyses were carried out by assuming various geometrical and material related parameters of a generic site. The objective of this study was to determine the gross response of a generic porous reservoir. The site geometry for this study assumed a cylindrical model 122 m in dia and 57 m high including thicknesses for the cap, porous, and base rock formations. The central portion of the porous zone was assumed to be at a depth of 518 m and at an initial temperature of 20/sup 0/C. Cyclic loading conditions of compressed air consisted of pressure values in the range of 4.5 to 5.2 MPa and temperature values between 143 and 204/sup 0/C.Various modes of structural behavior were studied. These response modes were analyzed using loading conditions of temperature and pressure (in the porous zone) corresponding to various operational states during the first year of simulated site operation. The results of the structural analyses performed indicate that the most severely stressed region will likely be in the wellbore vicinity and hence highly dependent on the length of and placement technique utilized in the well production length. Analyses to address this specific areas are currently being pursued.

Lejere der bliver sat ud af deres bolig

DEFF Research Database (Denmark)

Christensen, Gunvor; Nielsen, Torben Heien

Antallet af lejere, der bliver sat ud af deres bolig, er steget i perioden 2002-06. I 2006 blev 2600 husstande, svarende til 0,1 pct. af samtlige husstande i Danmark, sat ud af deres bolig. Stigningen er især sket i de fem største byer: København, Århus, Odense, Ålborg og Esbjerg. I dette...... skal give viden om, hvilke årsager der er til, at nogle lejere bliver sat ud af deres bolig, og hvorfor der er sket en stigning i antallet af udsættelser. Den endelige afrapportering af undersøgelsen af udsættelser i Danmark vil ske i foråret 2008. Undersøgelsen er finansieret af Socialministeriet....

Air-guided photonic-crystal-fiber pulse-compression delivery of multimegawatt femtosecond laser output for nonlinear-optical imaging and neurosurgery

Science.gov (United States)

Lanin, Aleksandr A.; Fedotov, Il'ya V.; Sidorov-Biryukov, Dmitrii A.; Doronina-Amitonova, Lyubov V.; Ivashkina, Olga I.; Zots, Marina A.; Sun, Chi-Kuang; Ömer Ilday, F.; Fedotov, Andrei B.; Anokhin, Konstantin V.; Zheltikov, Aleksei M.

2012-03-01

Large-core hollow photonic-crystal fibers (PCFs) are shown to enable a fiber-format air-guided delivery of ultrashort infrared laser pulses for neurosurgery and nonlinear-optical imaging. With an appropriate dispersion precompensation, an anomalously dispersive 15-μm-core hollow PCF compresses 510-fs, 1070-nm light pulses to a pulse width of about 110 fs, providing a peak power in excess of 5 MW. The compressed PCF output is employed to induce a local photodisruption of corpus callosum tissues in mouse brain and is used to generate the third harmonic in brain tissues, which is captured by the PCF and delivered to a detector through the PCF cladding.

Biodegradation of BOD and ammonia-free using bacterial consortium in aerated fixed film bioreactor (AF2B)

Science.gov (United States)

Prayitno, Rulianah, Sri; Saroso, Hadi; Meilany, Diah

2017-06-01

BOD and Ammonia-free (NH3-N) are pollutants of hospital wastewater which often exceed the quality standards. It is because biological processes in wastewater treatment plant (WWTP) have not been effective in degrading BOD and NH3-N. Therefore, a study on factors that influence the biodegradation of BOD and NH3-N by choosing the type of bacteria to improve the mechanisms of biodegradation processes is required. Bacterial consortium is a collection of several types of bacteria obtained from isolation process, which is known to be more effective than a single bacterial in degrading pollutants. On the other hand, AF2B is a type of reactor in wastewater treatment system. The AF2B contains a filter media that has a large surface area so that the biodegradation process of pollutants by microorganism can be improved. The objective of this research is to determine the effect of volume of starter and air supplies on decreasing BOD and NH3-N in hospital wastewater using bacterial consortium in the AF2B on batch process. The research was conducted in three stages: the making of the growth curve of the bacterial consortium, bacterial consortium acclimatization, and hospital wastewater treatment in the AF2B with batch process. The variables used are the volume of starter (65%, 75%, and 85% in volume) and air supplies (2.5, 5, and 7.5 L/min). Meanwhile, the materials used are hospital wastewater, bacterial consortium (Pseudomonas diminuta, Pseudomonas capica, Bacillius sp, and Nitrobacter sp), blower, and AF2B. AF2B is a plastic basin containing a filter media with a wasp-nest shape used as a medium for growing the bacterial consortium. In the process of making the growth curve, a solid form of bacterial consortium was dissolved in sterilized water, then grown in a nutrient broth (NB). Then, shaking and sampling were done at any time to determine the path growth of bacterial consortium. In the acclimatization process, bacterial isolates were grown using hospital wastewater as a

Subcutaneous emphysema, pneumomediastinum, pneumothorax, pneumoperitoneum, and pneumoretroperitoneum by insufflation of compressed air at the external genitalia in a child.

Science.gov (United States)

Muramori, Katsumi; Takahashi, Yukiko; Handa, Noritoshi; Aikawa, Hisayuki

2009-04-01

A 7-year-old girl with concurrent subcutaneous emphysema, pneumomediastinum, pneumothorax, pneumoperitoneum, and pneumoretroperitoneum arrived at our facility. Compressed air at 5 atm of pressure was insufflated through the nozzle of a spray gun over her external genitalia. She was admitted for a small amount of genital bleeding and significant subcutaneous emphysema extending from the cheek to the upper body. Radiographic examination of the abdomen was suggestive of a visceral perforation, but she was managed conservatively and discharged in satisfactory condition without surgical intervention. The female genitalia possibly served as the entry point for air into the retroperitoneum and peritoneal cavity, with subsequent migration of air through the esophageal hiatus that resulted in pneumomediastinum, pneumothorax, and extensive subcutaneous emphysema.

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....

Hærdeteknologi og Holdbarhed af Betonkonstruktioner

DEFF Research Database (Denmark)

Sørensen, Eigil V.

Kurset Hærdeteknologi og Holdbarhed af Betonkonstruktioner afholdes i 1. og 2. periode af forårssemesteret 2006. Kurset sigter på at give de studerende en grundlæggende forståelse af, hvorledes man designer og udfører holdbare betonkonstruktioner....

International fragmentation af produktionen og vertikal disintegration af styringsformer i produktionskæderne

DEFF Research Database (Denmark)

Refslund, Bjarke

Stigende international økonomisk integration har betydet en stigende fragmentering af produktionen, hvor store dele udføres i forskellige lande. Dertil kommer en stigende disintegration af vertikale styringsformer i produktions-værdikæder (Global Value Chains). Dette konferencepaper diskutere...

Retention of fission products in air filters

International Nuclear Information System (INIS)

Sobnack, R.

1986-01-01

The plume from the Chernobyl nuclear reactor reached London in the morning of 1st May. Less than two weeks later, the Physics Department, University of Surrey, reported a measurable level of radioactivity in air filters. On 15th May air filters from within the air conditioning plant of the Radioisotope Department at the London Hospital were removed for radiation checks. Crude tests with a geiger counter gave readings of 5-10 times higher than background levels. Gamma-ray spectroscopy of the departmental air filters (AF1) using a 127 mm NaI detector revealed a pattern characteristic of emissions of fission products from a nuclear reactor. Another air filter (AF2), from the home of a member of staff, was much less active. Because of the complexity of the gamma-ray spectrum and the relatively high level of emission from the departmental air filter, a thorough investigation was carried out using a high purity germanium detector. (author)

Identifikation af forkullet lig ved hjælp af ganeaftryk og koralnyresten

DEFF Research Database (Denmark)

Leth, Peter Mygind; Bindslev, Dorthe Arenholt; Kristensen, Ingrid Bayer

1997-01-01

En retstodontologisk undersøgelse af en dødfunden, uidentificeret person, bygger almindeligvis på en undersøgelse af tandsættet. Hvis personen er tandløs må andre identifikationsmetoder tages i anvendelse. Fingeraftryk er et almindelig kendt eksempel på en alternativ metode, som bygger på, at cri...

An Interface Transformation Strategy for AF-IPPS

Science.gov (United States)

2012-12-01

Oracle, or SAP . Like other AF and Department of Defense (DoD) ERP programs, AF-IPPS is expected to have 100+ interfaces with 90+ external trading partners...platform such as PeopleSoft, Oracle, or SAP . Like other AF and Department of Defense (DoD) ERP programs, AF-IPPS is expected to have 100...currently perform these functions. The core of AF-IPPS will be implemented using an Enterprise Resource Planning ( ERP ) platform such as PeopleSoft

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...

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...

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...

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...

Magtens repræsentation af danskhed

DEFF Research Database (Denmark)

Madsen, Carsten

2016-01-01

Med udgangspunkt i Maurice Charlands begreb om konstitutiv retorik og Jacques Derridas dekonstruktion af repræsentationslogik foretager artiklen en kritisk analyse og fortolkning af repræsentationen af dansk nationalidentitet, sådan som den kommer til udtryk i Dronning Margrethes nytårstaler...

På kanten af ungdomslivet

DEFF Research Database (Denmark)

Sørensen, Niels Ulrik; Pless, Mette

2015-01-01

). Parallelt hermed fortælles moderne ungdomsliv (i ungdomssociologien) frem gennem ”…theoretical frameworks based on urban experiences which capture neither the lives of rural young people nor the spatial dimensions of the structures and cultures that make up contemporary youth.” (Farrugia 2013......, at yderområder er hårdt ramt af ungdomsarbejdsløshed (Bjørnsted & Andersen 2013), at områderne er præget af høj koncentration af unge med arbejderklassebaggrund (Ottosen et a 2010), mens de uddannelsesorienterede og ressourcestærke unge er tilbøjelige til at flytte væk og ind til byerne (Helve 2003). Og ser man...... stedstilknytning og stedbundne ressourcer. Teoretiske perspektiver, der peger på vigtigheden af en mere ”..spatialised youth sociology that is sensitive to macro-level processes producing different spaces, as well as the local, emplaced ways in which young people are responding to social changest hat shape...

For bestemmelse af drivhusgasudledning ved udtagning/Ekstensivering af landbrugsjorder på kulstofrige lavbundsjorder

DEFF Research Database (Denmark)

Gyldenkærne, Steen; Greve, Mogens Humlekrog

Sammenfatning: Rapporten beskriver hvordan man kan beregne ændringen i drivhusgasemissionen ved omlægning af landbrugsjord til naturarealer. Rapporten er primært rettet mod tilskudsordningen vedr. udtagning af organiske lavbundsjorde, men kan også anvendes i andre sammenhænge. Rapporten anvender de...

Combined rankine and vapor compression cycles

Science.gov (United States)

Radcliff, Thomas D.; Biederman, Bruce P.; Brasz, Joost J.

2005-04-19

An organic rankine cycle system is combined with a vapor compression cycle system with the turbine generator of the organic rankine cycle generating the power necessary to operate the motor of the refrigerant compressor. The vapor compression cycle is applied with its evaporator cooling the inlet air into a gas turbine, and the organic rankine cycle is applied to receive heat from a gas turbine exhaust to heat its boiler within one embodiment, a common condenser is used for the organic rankine cycle and the vapor compression cycle, with a common refrigerant, R-245a being circulated within both systems. In another embodiment, the turbine driven generator has a common shaft connected to the compressor to thereby eliminate the need for a separate motor to drive the compressor. In another embodiment, an organic rankine cycle system is applied to an internal combustion engine to cool the fluids thereof, and the turbo charged air is cooled first by the organic rankine cycle system and then by an air conditioner prior to passing into the intake of the engine.

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....

Fermentering af korn øger fordøjeligheden af næringsstoffer

DEFF Research Database (Denmark)

Pedersen, Anni Øyan; Jørgensen, Henry; Bach Knudsen, Knud Erik

2010-01-01

foderblandingerne med ikke-fermentet korn var dog lavere end normalt, hvilket kan have påvirket resultaterne, så effekten af fermentering er større i dette forsøg, end hvad der normalt kan forventes. Kornet var groft formalet (ca. 30 % under 1 mm), hvilket kan have påvirket resultaterne. Ved finere formaling af...

Bilag til forskningsoversigt - Effekterne af Cooperative Learning

DEFF Research Database (Denmark)

Larsen, Lea Lund

Ved en opsamling af de empiriske studier vedrørende effekten af CL inden for voksenundervisningsfeltet ses en overvægt af studier, som rapporterer en positiv effekt af CL i forhold til de voksne lærendes faglige udbytte. En meta-analyse over 168 amerikanske undersøgelser på universitetsniveau vis...

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...

Hvorfor lejere bliver sat ud af deres bolig

DEFF Research Database (Denmark)

Nielsen, Torben Heien; Christensen, Gunvor

Antallet af lejere, der bliver sat ud af deres bolig, er steget fra 1499 i 2002 til 2589 i 2006. Lejere kan blive sat ud af deres bolig, hvis de ikke betaler deres husleje til tiden, eller hvis de ikke overholder husordenen det sted de bor. Denne rapport beskriver årsager til, at lejere bliver sat...... ud af deres boliger og baggrunden for stigningen i antallet af udsættelser. desuden beskriver rapporten konsekvenser af en udsættelse og kommer med en række anbefalinger til indsatsområder. Af afgørende betydning for, at lejere bliver sat ud af deres bolig, er lav indkomst, lavt rådighedsbeløb, stor...

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

International Nuclear Information System (INIS)

Ibrahim, H.; Younes, R.; Ilinca, A.; Dimitrova, M.; Perron, J.

2010-01-01

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.

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....

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...

Fundering af mindre bygninger

DEFF Research Database (Denmark)

Larsen, J.; Ballisager, C.C.

Denne SBI-anvisning indeholder en gennemgang af de jordbunds- og grundvandsforhold, som er bestemmende for funderingen af en bygning. Specielt gennemgås de betingelser, der skal være opfyldt, for at man på forsvarlig måde kan fundere en mindre bygning i traditionel udformning. Publikationen...

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.

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.

Udvikling af vejledningspraksis i kurser for undervisere i brugen af blended learning-aktiviteter

DEFF Research Database (Denmark)

Stenalt, Maria Hvid; Wichmann-Hansen, Gitte; Rossen, Dorte Sidelmann

Hvert semester tilbyder Center for Undervisning og Læring (CUL) ved School of Business and Social Sciences ved Aarhus Universitet et 1-årig langt kompetenceudviklingsforløb i brugen af blended learning for lektorer og professorer. I løbet af denne periode skal deltagerne gennemføre et indledende...... blended learning-kursusforløb på 5 uger efterfulgt af en udviklings- og afprøvningsfase. Som afslutning skal deltagerne skrive en refleksionsrapport. Forløbet indebærer to vejledningsmøder med en eller flere af de undervisningsudviklere fra CUL, der er ansvarlige for forløbet: 1) Et individuelt...... vejledningsmøde, hvor deltagerne skal finde frem til, hvordan de vil eller kan omlægge deres undervisning til blended learning og 2) et kollektivt vejledningsmøde efter første udviklingsfase, hvor deltagerne modtager feedback på deres igangværende udviklingstiltag fra gruppemedlemmer og undervisningsudviklere. Et...

Videoanalyse af social interaktion

DEFF Research Database (Denmark)

Igennem de sidste 40 år er videooptagelser af praksis blevet anvendt som et redskab i forskning af social interaktion inden for f.eks. læring, design, mediering, kommunikationstræning og i sundhedsvæsenet. Videoanalyse af social interaktion giver et stærkt metodisk, teoretisk og praktisk blik ind i...... videoanalyse og viser, hvordan man som forsker og studerende kan bruge videoanalyse til at undersøge social interaktion. Bogens temaer og spørgsmål udgør således en grundsten i arbejdet med videoanalyse på professions-, universitets- og forskeruddannelser såvel som i forskning mere generelt og omfatter: - de...

Digital innovation af folkeskolernes åbenhed og sammenlignelighed

DEFF Research Database (Denmark)

Andersen, Kim Normann; Henriksen, Helle Zinner; Agger Nielsen, Jeppe

2013-01-01

Denne artikel præsenterer en normativ model (Public Sector Process Rebuilding, PPR), som kan indfange, hvor innovativt offentlige organisationer anvender digitale løsninger. Optag af digital innovation anskues ofte i litteraturen binært – enten er innovationen anskaffet eller ikke anskaffet. Vores...... argument er imidlertid, at optag af digitale innovationer kan gradbøjes. Vores sigte er derfor at få fokus væk fra anskaffelse og mere i retning af udnyttelse af digitaliseringen med henblik på at skabe forbedring af kerneydelserne og gavne slutbrugerne. Med empirisk afsæt i danske folkeskolers tolkning af...

Fluorerede stoffer i mademballage af pap og papir

DEFF Research Database (Denmark)

Trier, Xenia; Cederberg, Tommy Licht; Jensen, Lisbeth Krüger

andre typer af madbokse. Prøverne er blevet analyseret for flere forskellige typer af fluorerede stoffer, der anvendes til at imprægnere disse typer af emballager, så de ikke suger fedt eller vand. I ingen af prøverne er der fundet indhold af fluorerede stoffer, der overstiger analysemetodens...

Aspekter af integrationsindsatsen i 6 kommuner

DEFF Research Database (Denmark)

Rosdahl, Anders

Dette arbejdspapir præsenterer resultaterne af en mindre kvalitativ undersøgelse af kommuners indsats for at bringe nyankomne flygtninge og indvandrere i beskæftigelse. Undersøgelsen er en opfølgning på en kvantitativ benchmarkanalyse, som er gennemført af Amternes og Kommunernes Forskningsinstit...

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...

Boligboblen pustes op af bankerne

DEFF Research Database (Denmark)

Ravn, Ib

2017-01-01

Den aktuelle boligboble blæses i vejret af bankerne, der gennem opkøb af realkreditobligationer skaber nye penge og dermed presser boligpriserne i vejret - en kreditfinansieret bolig- eller finansboble....

Domesticeringen af Ford i Danmark:Den kulturelle tilegnelse af Ford og fordismen, 1920-1940

OpenAIRE

Wagner, Michael

2009-01-01

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 ...

29 CFR 1926.803 - Compressed air.

Science.gov (United States)

2010-07-01

... ventilated, and there shall be no pockets of dead air. Outlets may be required at intermediate points along the main low-pressure air supply line to the heading to eliminate such pockets of dead air... of structures of wood over or near shafts. (6) Tunnels shall be provided with a 2-inch minimum...

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....

Monitering, modellering og miljøvurdering af fuldskala afværge af TCE fourening ved stimuleret reduktiv deklorering

DEFF Research Database (Denmark)

Westergaard, Claus; Lemming, Gitte; Janniche, Gry Sander

På Sortebrovej 26 i Tommerup blev der i 2006 gennemført afværgeforanstaltninger ved stimuleret reduktiv deklorering (SRD) ved injektion af donor og bakterier i kildeområdet med henblik på at oprense en forurening med TCE. Kildeområdet befinder sig 10-20 m u. t. i sandet og opsprækket moræneler...... gunstige forhold for nedbrydning af de klorerede ethener ved reduktiv deklorering. Der ses da også en klar dominans af nedbrydningsprodukterne DCE og VC samt ethen og ethan i grundvandet. I nogle boringer, ses dog en stagnerende omsætning af TCE og DCE i grundvandet. Årsagen her til kan være, at donoren...... da også fordoblet fra 2008 til 2010. Der er observeret zoner med betydelig omsætning af TCE, hvor cis-DCE dominerer, og der ses generelt VC og ethen centralt i disse zoner. Koncentrationsniveauet af fermenteringsprodukter er aftaget og består ved en sandslire (B370 K1) alene af acetat og methan...

Vurdering af effekten af en vindmøllepark ved Overgaard på forekomsten af fugle i EF-fuglebeskyttelsesområde nr. 15

DEFF Research Database (Denmark)

Clausen, P.; Larsen, J. K.

forekomsten af en række arter der enten yngler eller raster inden for EF-fuglebeskyttelsesområdet, og er omfattet af EF-fuglebeskyttelsesdirektivets bilag I. Det drejer sig om arterne skarv Phalacrocorax carbo sinensis, blå kærhøg Circus cyaneus, hjejle Pluvialis apricaria, brushane Philomachus pugnax, klyde...

Thermal analysis of near-isothermal compressed gas energy storage system

International Nuclear Information System (INIS)

Odukomaiya, Adewale; Abu-Heiba, Ahmad; Gluesenkamp, Kyle R.; Abdelaziz, Omar; Jackson, Roderick K.; Daniel, Claus; Graham, Samuel; Momen, Ayyoub M.

2016-01-01

Highlights: • A novel, high-efficiency, scalable, near-isothermal, energy storage system is introduced. • A comprehensive analytical physics-based model for the system is presented. • Efficiency improvement is achieved via heat transfer enhancement and use of waste heat. • Energy storage roundtrip efficiency (RTE) of 82% and energy density of 3.59 MJ/m"3 is shown. - Abstract: Due to the increasing generation capacity of intermittent renewable electricity sources and an electrical grid ill-equipped to handle the mismatch between electricity generation and use, the need for advanced energy storage technologies will continue to grow. Currently, pumped-storage hydroelectricity and compressed air energy storage are used for grid-scale energy storage, and batteries are used at smaller scales. However, prospects for expansion of these technologies suffer from geographic limitations (pumped-storage hydroelectricity and compressed air energy storage), low roundtrip efficiency (compressed air energy storage), and high cost (batteries). Furthermore, pumped-storage hydroelectricity and compressed air energy storage are challenging to scale-down, while batteries are challenging to scale-up. In 2015, a novel compressed gas energy storage prototype system was developed at Oak Ridge National Laboratory. In this paper, a near-isothermal modification to the system is proposed. In common with compressed air energy storage, the novel storage technology described in this paper is based on air compression/expansion. However, several novel features lead to near-isothermal processes, higher efficiency, greater system scalability, and the ability to site a system anywhere. The enabling features are utilization of hydraulic machines for expansion/compression, above-ground pressure vessels as the storage medium, spray cooling/heating, and waste-heat utilization. The base configuration of the novel storage system was introduced in a previous paper. This paper describes the results

Selektiv avl af racehunde og -katte

DEFF Research Database (Denmark)

Sandøe, Peter; Meyer, Iben Helene Coakley; Fredholm, Merete

2014-01-01

Dette kapitel ser nærmere på de velfærdsmæssige problemstillinger, der opstår som følge af måden, hvorpå racehunde og -katte påvirkes gennem selektiv avl. Først beskrives, hvordan avlen af racehunde og -katte er organiseret. Dernæst gøres der rede for de dyrevelfærdsmæssige konsekvenser heraf....... Selektiv avl af hunde og katte tjener til at vedligeholde en stor racemæssig diversitet. De racemæssige forskelle gør det muligt for mennesker at vælge især hunde, der har nogle egenskaber, som passer til individuelle behov og ønsker. Desværre er der også en række bivirkninger for de pågældende dyrs...... problemer, som knytter sig til selektiv avl af racehunde og -katte, gennemgås og diskuteres mulige praktiske tiltag, som kan trække udviklingen i retning af at reducere forekomsten af disse problemer....

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.

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.

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...

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.

Assessment of market potential of compressed air energy storage systems

Science.gov (United States)

Boyd, D. W.; Buckley, O. E.; Clark, C. E., Jr.

1983-12-01

This report describes an assessment of potential roles that EPRI might take to facilitate the commercial acceptance of compressed air energy storage (CAES) systems. The assessment is based on (1) detailed analyses of the market potential of utility storage technologies, (2) interviews with representatives of key participants in the CAES market, and (3) a decision analysis synthesizing much of the information about market and technology status. The results indicate a large potential market for CAES systems if the overall business environment for utilities improves. In addition, it appears that EPRI can have a valuable incremental impact in ensuring that utilities realize the potential of CAES by (1) continuing an aggressive information dissemination and technology transfer program, (2) working to ensure the success of the first United States CAES installation at Soyland Power Cooperative, (3) developing planning methods to allow utilities to evaluate CAES and other storage options more effectively and more realistically, and (4) supporting R and D to resolve residual uncertainties in first-generation CAES cost and performance characteristics. Previously announced in STAR as N83-25121

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...

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...

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...

Annual performance investigation and economic analysis of heating systems with a compression-assisted air source absorption heat pump

International Nuclear Information System (INIS)

Wu, Wei; Shi, Wenxing; Wang, Baolong; Li, Xianting

2015-01-01

Highlights: • Optimal compression ratio of CASAHP is obtained for the maximum energy saving rate. • Annual performance is improved by 10–20% compared to ASAHP without compression. • Energy saving rate is 17.7–29.2% and investment is reduced to 30–60% for CASAHP. • Both compression and partial-design enhance the economy with given energy saving. • Payback time is reduced from 12–32 to 3–6 years by compression and partial-design. - Abstract: The compression-assisted air source absorption heat pump (CASAHP) is a promising alternative heating system in severe operating conditions. In this research, parameter studies on the annual performance under various compression ratios (CRs) and source temperatures are performed to achieve the maximum energy saving rates (ESRs). Economic analyses of the CASAHP under different CRs and partial-design ratios are conducted to obtain an optimal design that considers both energy savings and economy improvements. The results show that the optimal CR becomes higher in colder regions and with lower heat source temperatures. For a source temperature of 130 °C, the optimal CR values in all of the cities are within 2.0. For source temperatures from 100 to 130 °C, the maximum ESR is in the range of 17.7–29.2% in the studied cities. The efficiency improvement rate (EIR) caused by compression in a severe source condition can reach 10.0–20.0%. From the viewpoint of economy, the relative investment of CASAHP is reduced to 30–60% with a CR of 2.0–3.0. With a 2–6% sacrifice in ESR, the payback period can be reduced from 12–32 to 5–9 years using compression. Partial-design of the CASAHP can further reduce the payback period to 3–6 years with a partial-design ratio of 50% and a CR of 2.8. Additionally, CRs and partial-design ratios are designed comprehensively by seeking the maximum ESR for a given acceptable payback period

En litteraturbaseret gennemgang af mulige velfærdsmæssig betydning af brugen af længerevarende smertelindring til kalve efter afhorning

DEFF Research Database (Denmark)

Herskin, Mette S.; Nielsen, Bodil Højlund

2018-01-01

Dette er et udvidet sammendrag af vidensyntesen. Store dele af vidensyntesen er under review til et videnskabeligt tidsskrift, og kan derfor ikke offentliggøres elektronisk før denne proces er afsluttet. Den fulde rapport kan fremsendes pr. mail. Hvis du gerne vil have den tilsendt, så send en mail...

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...... Kofod Olsen, Teresa Gleadowe, Helle Ryberg, Kirse Junge-Stevnsborg, Malene Natascha Ratcliffe, Pelin Uran, Jacob Fabricius, Lotte Juul Petersen, Jacob Lillemose, Solvej Helweg Ovesen, Frederikke Hansen & Tone Olaf Nielsen (kuratorisk aktion) og Temporary Services....

Evaluering af kollegial supervision

DEFF Research Database (Denmark)

Petersen, Anne Line Bjerre Folsgaard; Bager, Lene Tortzen; Jørgensen, Mette Eg

2015-01-01

Videoen er en evaluering af arbejdet med en metodisk tilgang til kollegial supervision på VIA Ergoterapeutuddannelsen gennem et par år. Evalueringen sætter fokus på selve metoden, der er anvendt til kollegial supervision. Derudover er der fokus på erfaringer og udbytte af at arbejde systematisk med...... kollegial supervision blandt undervisere på VIA Ergoterapeutuddannelsen....

Effekter af koordineret hjerneskaderehabilitering. Et systematisk litteraturreview

DEFF Research Database (Denmark)

Glintborg, Chalotte; Hansen, Tia G. B.

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......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...

Preliminary long-term stability criteria for compressed air energy storage caverns in salt domes

Energy Technology Data Exchange (ETDEWEB)

Thoms, R.L.; Martinez, J.D.

1978-08-01

Air storage caverns, which are an essential and integral component of a CAES plant, should be designed and operated so as to perform satisfactorily over the intended life of the overall facility. It follows that the long-term ''stability'' of air storage caverns must be considered as a primary concern in projecting the satisfactory operation of CAES facilities. As used in the report, ''stability'' of a storage cavern implies the extent to which an acceptable amount of cavern storage volume can be utilized with routine maintenance for a specified time interval, e.g., 35 years. In this context, cavern stability is relative to both planned utilization and time interval of operation. The objective of the study was to review the existing literature and consult knowledgeable workers in the storage industry, and then report state-of-the-art findings relative to long-term stability of compressed air energy storage caverns in salt domes. Further, preliminary cavern stability criteria were to be presented in a form consistent with the amount of information available on cavern performance in salt domes. Another objective of the study was to outline a methodology for determining the long-term stability of site-specific CAES cavern systems in salt domes.

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....

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.

Erfaringer fra nedrivning af boligblok i Rødbyhavn

DEFF Research Database (Denmark)

Eriksen, Søren Skibstrup; Hansen, Klaus; Krogh, Hanne

Denne meddelelse indeholder en beskrivelse af nedrivningen af et betonelementbyggeri. Der er foretaget en registrering af energiforbrug i forbindelse med nedrivningen og bortskaffelsen samt en registrering af de miljøbelastende stoffer i bygningsaffaldet. Inden bebyggelsen blev revet ned, blev de...

Overvågning af karplanter i Suserup Skov

DEFF Research Database (Denmark)

Wind, P.

1999-01-01

Vejler, i alt ca. 5.500 ha. Feltstationen blev oprettet i 1978, og siden har observatørerne registreret fuglelivet i Vejlerne og de omgivende arealer foruden vandstand, saltholdighed og drift af området. Tipperne ligger i den sydlige del af Ringkøbing Fjord. Fuglelivet blev fredet i 1898. Reservatet blev...... en samlet fredning af Vadehavet, omfatter øen Langli på 80 ha og vandarealer på i alt ca. 8.000 ha. Øen består af klitter og salte strandenge. Vandområdet er præget af tidevand, hvor vidtstrakte sand- og mudderflader og spredte muslingebanker er synlige ved lavvande. Vorsø ligger i Horsens Fjord...... saltholdighed i Ringkøbing Fjord bevirker, at vandplanter vokser dårligt eller forsvinder. Vandplanter udgør en væsentlig del af føden for visse andefugle og kan derfor have stor betydning for antallet af rastende fugle. Der blev registreret lave antal af knortegå, gråand, pibeand og krikand. Af blishøne blev...

Miljørigtig ombygning af Mallinggård

DEFF Research Database (Denmark)

Hansen, Ernst Jan de Place

2002-01-01

Resume af rapport om den byggetekniske anvendelse af alternativ isolering ved en ombygning af Mallinggårds lade til undervisningslokaler, udarbejdet af Bent Møller fra Rudolf Steiner Skolen i Skanderborg under Energistyrelsens udviklingsprogram "Miljø- og arbejdsmiljøvenlig isolering"...

Death from Barotrauma Due to Compressed Air: A Medico-legal Analysis.

Science.gov (United States)

Giugliano, Pasquale; Massoni, Francesco; Crisci, Antonello; Ricci, Serafino

2016-11-01

Lesions of the digestive tract due to barotrauma resulting from compressed air application are not common, are rarely lethal, and largely affect the sigmoid and descending colon. Moreover, their pathogenic mechanism is a topic of discussion because these lesions have multiple characteristics. Here, the authors describe an autoptic case of death from lesions of the ascending and transverse segments, with perforations and bleeding suffusions as well as ischemic areas covered the colonic wall that was extremely thinned, congested, and hemorrhagic, with considerable flattening leading to disappearance of the mucosal folds and with numerous petechial hemorrhages. The pathological framework of lung congestion made it possible to identify the mechanism responsible for this death as depletion of the heart's pumping function, which contributed significantly to the acute respiratory failure due to respiratory distress as well as to reduced mobility of the diaphragm due to intestinal distension. Acute heart failure played an important role in this death. © 2016 American Academy of Forensic Sciences.

Influence of extensive compressed natural gas (CNG) usage on air quality

Science.gov (United States)

Suthawaree, Jeeranut; Sikder, Helena Akhter; Jones, Charlotte Emily; Kato, Shungo; Kunimi, Hitoshi; Mohammed Hamidul Kabir, Abu Naser; Kajii, Yoshizumi

2012-07-01

Compressed Natural Gas (CNG) is an inexpensive, indigenous energy resource which currently accounts for the majority of automobile and domestic energy consumption in Bangladesh. This extensive CNG usage, particularly within the capital city, Dhaka, heavily influences the atmospheric composition (and hence air quality), yet to date measurements of trace gases in regions dominated by CNG emissions are relatively limited. Here we report continuous observations of the atmospherically important trace gases O3, CO, SO2, NOx and volatile organic compounds (VOC), in ambient air in Dhaka City, Bangladesh, during May 2011. The average mixing ratios of O3, CO, SO2, and NOx for the measurement period were 18.9, 520.9, 7.6 and 21.5 ppbv, respectively. The ratios of CO to NO reveal that emissions from gasoline and CNG-fuelled vehicles were dominant during the daytime (slope of ˜26), while in contrast, owing to restrictions imposed on diesel fuelled vehicles entering Dhaka City, emissions from these vehicles only became significant during the night (slope of ˜10). The total VOC mixing ratio in Dhaka was ˜5-10 times higher than the levels reported in more developed Asian cities such as Tokyo and Bangkok, which consequently gives rise to a higher ozone formation potential (OFP). However, the most abundant VOC in Dhaka were the relatively long-lived ethane and propane (with mean mixing ratios of ˜115 and ˜30 ppbv, respectively), and as a consequence, the ozone formation potential per ppb carbon (ppbC) was lower in Dhaka than in Tokyo and Bangkok. Thus the atmospheric composition of air influenced by extensive CNG combustion may be characterized by high VOC mixing ratios, yet mixing ratios of the photochemical pollutant ozone do not drastically exceed the levels typical of Asian cities with considerably lower VOC levels.

Et nationalt studie af bankrøveri

DEFF Research Database (Denmark)

Hansen, Maj; Elklit, Ask

11,1 % (n = 41) af ASD og seks måneder efter røveriet led 6,2 % (n = 23) af PTSD. Begge prævalenser var begrænset af kravet om undgåelsessymptomer (ASD uden undgåelse: 14 %, PTSD uden undgåelse: 17,8 %), men ASD diagnosen var især begrænset af kravet om dissociationssymptomer (ASD uden dissociation......: 26,7 %). Hierarkisk regressionsanalyse viste, at 51 % af variansen i PTSD sværhedsgrad blev forklaret af peritraumatisk dissociation, ASD sværhedsgrad, emotionel coping og negative tanker om egen person og evner. ASD sværhedsgrad var den stærkeste prædiktorer for PTSD sværhedsgrad og forudsagde alene...... diagnoser. Særligt ASD sværhedsgrad og negative tanker om egen person og evner synes at kunne forudsige PTSD sværhedsgrad efter bankrøveri. Det anbefales derfor, at ”Acute Stress Disorder Scale” anvendes til at screene for PTSD efter bankrøveri. Fremtidig forskning anbefales at fokusere på udvikling af...

Typebestemmelse af de danske M. bovis stammer

DEFF Research Database (Denmark)

Kokotovic, Branko

Mycoplasma bovis er en af de mest betydningsfulde mykoplasma i kvægbruget på verdensplan. Bakterien findes oftest i forbindelse med mastitis, lunge- og ledbetændelse, men andre kliniske manifestationer kan også forekomme. Der findes ikke præcise, nyere beregninger over konsekvenser af M. bovis...... relateret sygdomme, men det anses, at infektionen hvert år globalt set pålægger en økonomisk byrde til kvægbruget i en multimillion skala. M. bovis blev for første gang påvist i Danmark i 1981 og gennem 1980’erne har bakterien forårsaget store udbrud af mastitis. I de følgende årtier blev bakterien isoleret...... sporadisk fra mange forskellige kvægbesætninger, men på trods af en tilsyneladende stigende forekomst i 1990’erne, blev der ikke registret omfattende sundhedsmæssige problemer som følge af M. bovis smitte. Siden 2011 er M. bovis dog kommet i fokus igen på grund af alvorlige udbrud af især ledbetændelse, men...

E1AF degradation by a ubiquitin-proteasome pathway

International Nuclear Information System (INIS)

Takahashi, Akiko; Higashino, Fumihiro; Aoyagi, Mariko; Yoshida, Koichi; Itoh, Miyuki; Kobayashi, Masanobu; Totsuka, Yasunori; Kohgo, Takao; Shindoh, Masanobu

2005-01-01

E1AF is a member of the ETS family of transcription factors. In mammary tumors, overexpression of E1AF is associated with tumorigenesis, but E1AF protein has hardly been detected and its degradation mechanism is not yet clear. Here we show that E1AF protein is stabilized by treatment with the 26S protease inhibitor MG132. We found that E1AF was modified by ubiquitin through the C-terminal region and ubiquitinated E1AF aggregated in nuclear dots, and that the inhibition of proteasome-activated transcription from E1AF target promoters. These results suggest that E1AF is degraded via the ubiquitin-proteasome pathway, which has some effect on E1AF function