WorldWideScience

Sample records for dual relap5-3d-based engineering

  1. Development and application of a dual RELAP5-3D-based engineering simulator for ABWR

    Energy Technology Data Exchange (ETDEWEB)

    Yang, C.-Y. [Institute of Nuclear Engineering and Science, National Tsing Hua University, 101 Sec. 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Liang, Thomas K.S. [Institute of Nuclear Engineering and Science, National Tsing Hua University, 101 Sec. 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China)], E-mail: ksliang@alum.mit.edu; Pei, B.S.; Shih, C.K. [Institute of Nuclear Engineering and Science, National Tsing Hua University, 101 Sec. 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Chiang, S.C.; Wang, L.C. [Department of Nuclear Safety, Taiwan Power Company, 242 Sec. 3, Roosevelt Road, Taipei 10016, Taiwan (China)

    2009-10-15

    For any innovated plant design, the designed paper plant can be converted into a computer as a digital plant with advanced simulation techniques before being constructed into a real plant. A digital plant, namely engineering simulator, can be applied for: (1) verification of system design and system integration, (2) power test simulation, (3) plant transient and accident analyses, (4) plant abnormal and emergency procedure development and verification, (5) design change verification and analysis, etc. An advanced engineering simulator was successfully developed for the LungMen advanced boiling water reactor (ABWR) plant to support various applications before and after commercial operation. This plant specific engineering simulator was developed based on two separate RELAP5-3D modules synchronized on a commercial simulation platform, namely 3-Key Master. On this advanced LungMen plant simulation (ALPS) platform, major plant dynamics were simulated by two separate RELAP5-3D modules, one for reactor system modeling and the other for balance of plant (BOP) system modeling. Moreover, major control systems as well as emergency core cooling system (ECCS) were all simulated in great detail with built-in tasks of this commercial simulation platform. Different from real time calculation on training simulator, precision of engineering calculation is intentionally kept by synchronizing modules based on the most time-consuming one. During synchronization, each module will check its' own converge criteria in each small time advancement. This plant specific advanced ABWR engineering simulator has been successfully applied on: (1) licensing blowdown analysis of feed water line break (FWLB) for containment design; (2) phenomena investigation of low-pressure ECC injection bypass during FWLB; (3) analysis of FW pump performance during power ascending; (4) verification of plant vendor's pre-test calculations of each start-up test.

  2. Dual-fuel, dual-throat engine preliminary analysis

    Science.gov (United States)

    Obrien, C. J.

    1979-01-01

    A propulsion system analysis of the dual fuel, dual throat engine for launch vehicle applications was conducted. Basic dual throat engine characterization data were obtained to allow vehicle optimization studies to be conducted. A preliminary baseline engine system was defined.

  3. ISIFC - dual Biomedical Engineering School.

    Science.gov (United States)

    Butterlin, Nadia; Soto-Romero, Georges; Duffaud, Jacques; Blagosklonov, Oleg

    2007-01-01

    The Superior Institute for Biomedical Engineering (ISIFC), created in 2001, is part of the Franche-Comté University and is accredited by the French Ministry of National Education. Its originality lies in its innovative course of studies, which trains engineers in the scientific and medical fields to get both competencies. The Institute therefore collaborates with the University Hospital Centre of Besançon (CHU), biomedical companies and National Research Centres (CNRS and INSERM). The dual expertise trainees will have acquired at the end of their 3 years course covers medical and biological skills, scientific and Technical expertises. ISIFC engineers answer to manufacturer needs for skilled scientific and technical staff in instrumentation and techniques adapted to diagnosis, therapeutics and medical control, as well as the needs of potential users for biomedical devices, whether they are doctors, hospital staff, patients, laboratories, etc... Both the skills and the knowledge acquired by an ISIFC engineer will enable him/her to fulfil functions of study, research and development in the industrial sector.

  4. Dual-fuel, dual-mode rocket engine

    Science.gov (United States)

    Martin, James A. (Inventor)

    1989-01-01

    The invention relates to a dual fuel, dual mode rocket engine designed to improve the performance of earth-to-orbit vehicles. For any vehicle that operates from the earth's surface to earth orbit, it is advantageous to use two different fuels during its ascent. A high density impulse fuel, such as kerosene, is most efficient during the first half of the trajectory. A high specific impulse fuel, such as hydrogen, is most efficient during the second half of the trajectory. The invention allows both fuels to be used with a single rocket engine. It does so by adding a minimum number of state-of-the-art components to baseline single made rocket engines, and is therefore relatively easy to develop for near term applications. The novelty of this invention resides in the mixing of fuels before exhaust nozzle cooling. This allows all of the engine fuel to cool the exhaust nozzle, and allows the ratio of fuels used throughout the flight depend solely on performance requirements, not cooling requirements.

  5. Dual education and industrial cooperation in electrical engineering

    Science.gov (United States)

    Váradiné Szarka, A.

    2016-11-01

    Dual education in higher education is a new system in Hungary introduced by Mercedes Benz with cooperation of Kecskemet College. In the new system companies support certain number of students and provide them strong practical education in their field. Students applying successfully for dual education study together with non-dual students at the university, so they go through the same university courses as their non-dual colleagues, but while non-dual students’ academic year includes 2×14 weeks active semester and 2×6 weeks exam session, all over 40 weeks, dual students have 48 working weeks including study at the university and practicing at the company. The main question of the success which one is the most effective model to be applied. This paper summarises 2 models of dual education with their advantages and disadvantages and also it presents practical realization at the University of Debrecen with special attention to measurement and instrumentation. Dual education in BSc level electrical engineering course cooperates with 6 multinational companies of the region in four specialization. Dual education also has great impact to the modernisation of engineering education. Detailed study of dual education in field of instrumentation and measurement is provided in the paper.

  6. LPG diesel dual fuel engine – A critical review

    Directory of Open Access Journals (Sweden)

    B. Ashok

    2015-06-01

    Full Text Available The engine, which uses both conventional diesel fuel and LPG fuel, is referred to as ‘LPG–diesel dual fuel engines’. LPG dual fuel engines are modified diesel engines which use primary fuel as LPG and secondary fuel as diesel. LPG dual fuel engines have a good thermal efficiency at high output but the performance is less during part load conditions due to the poor utilization of charges. This problem can be overcome by varying factors such as pilot fuel quantity, injection timing, composition of the gaseous fuel and intake charge conditions, for improving the performance, combustion and emissions of dual fuel engines. This article reviews about the research work done by the researchers in order to improve the performance, combustion and emission parameters of a LPG–diesel dual fuel engines. From the studies it is shown that the use of LPG in diesel engine is one of the capable methods to reduce the PM and NOx emissions but at same time at part load condition there is a drop in efficiency and power output with respect to diesel operation.

  7. Dual fuel diesel engine operation using LPG

    Science.gov (United States)

    Mirica, I.; Pana, C.; Negurescu, N.; Cernat, Al; Nutu, N. C.

    2016-08-01

    Diesel engine fuelling with LPG represents a good solution to reduce the pollutant emissions and to improve its energetic performances. The high autoignition endurance of LPG requires specialized fuelling methods. From all possible LPG fuelling methods the authors chose the diesel-gas method because of the following reasons: is easy to be implemented even at already in use engines; the engine does not need important modifications; the LPG-air mixture has a high homogeneity with favorable influences over the combustion efficiency and over the level of the pollutant emissions, especially on the nitrogen oxides emissions. This paper presents results of the theoretical and experimental investigations on operation of a LPG fuelled heavy duty diesel engine at two operating regimens, 40% and 55%. For 55% engine load is also presented the exhaust gas recirculation influence on the pollutant emission level. Was determined the influence of the diesel fuel with LPG substitution ratio on the combustion parameters (rate of heat released, combustion duration, maximum pressure, maximum pressure rise rate), on the energetic parameters (indicate mean effective pressure, effective efficiency, energetic specific fuel consumption) and on the pollutant emissions level. Therefore with increasing substitute ratio of the diesel fuel with LPG are obtained the following results: the increase of the engine efficiency, the decrease of the specific energetic consumption, the increase of the maximum pressure and of the maximum pressure rise rate (considered as criteria to establish the optimum substitute ratio), the accentuated reduction of the nitrogen oxides emissions level.

  8. Fuel control system for dual fuel engines

    Energy Technology Data Exchange (ETDEWEB)

    Helmich, M.J.; Ryan, W.P.; Marvin, D.H.

    1987-11-24

    A fuel governing system for an engine adapted for operation on a first fuel and a second fuel is described comprising: a first fuel governing system including a spontaneous motion metering means; and a second fuel governing system, the second fuel governing system further comprising: means for providing a first signal indicative of position of the first fuel metering means, which signal approximates total load on the engine, means for providing a second signal of the selected percentage of first fuel relative to total load, means for controlling flow of the second fuel to the engine, which flow causes reflective displacement of the first fuel metering means, means for determining the difference between the first signal and the second signal, which difference is indicative of distance the first fuel metering means must be moved to attain the selected percentage of first fuel relative to total load, and means for causing operation of the means for controlling flow of the second fuel to the engine to cause displacement of the first fuel metering means equal to the distance the first fuel metering means must be moved to attain the selected percentage of first fuel relative to total load.

  9. CNG INJECTOR RESEARCH FOR DUAL FUEL ENGINE

    Directory of Open Access Journals (Sweden)

    Adam Majczak

    2017-03-01

    Full Text Available The article presents the tests results of the prototype design of hydraulically assisted injector, that is designed for gas supply into diesel engines. The construction of the injector allows for it positioning in the glow plug socket, so that the gas is injected directly into the combustion chamber. The cycle analysis of the four-cylinder Andoria ADCR engine with a capacity of 2.6 dm3 for different crankshaft rotational speeds allowed to determine the necessary time for fuel injection. Because of that, it was possible to determine the required mass flow rate of the injector, for replacing as much of the original fuel by gaseous fuel. To ensure a high value of flow inside the injector, supply pressure equal to 1 MPa was applied. High gas supply pressure requires high value of valve opening forces. For this purpose a injector with hydraulic control system, using a liquid under pressure for the opening process was designed. On the basis of air pressure measurements in the flow line after the injector, the analysis of opening and closing of the valve was made. Measurements of outflow mass of the injector were also carried out. The results showed that the designed injector meets the requirements necessary to supply ADCR engine by the CNG fuel.

  10. Ignition delay of dual fuel engine operating with methanol ignited by pilot diesel

    Institute of Scientific and Technical Information of China (English)

    Hongbo ZOU; Lijun WANG; Shenghua LIU; Yu LI

    2008-01-01

    An investigation on the ignition delay of a dual fuel engine operating with methanol ignited by pilot diesel was conducted on a TY1100 direct-injection diesel engine equipped with an electronic controlled methanol low-pressure injection system. The experimental results show that the polytropic index of compression process of the dual fuel engine decreases linearly while the ignition delay increases with the increase in methanol mass fraction. Compared with the conventional diesel engine, the igni-tion delay increment of the dual fuel engine is about 1.5° at a methanol mass fraction of 62%, an engine speed of 1600 r/min, and full engine load. With the elevation of the intake charge temperature from 20℃ to 40℃ and then to 60℃, the ignition delay of the dual fuel engine decreases and is more obvious at high temperature. Moreover, with the increase in engine speed, the ignition delay of the dual fuel engine by time scale (ms) decreases clearly under all engine operating conditions. However, the ignition delay of the dual fuel engine increases remark-ably by advancing the delivery timing of pilot diesel, espe-cially at light engine loads.

  11. Dual Expander Cycle Rocket Engine with an Intermediate, Closed-cycle Heat Exchanger

    Science.gov (United States)

    Greene, William D. (Inventor)

    2008-01-01

    A dual expander cycle (DEC) rocket engine with an intermediate closed-cycle heat exchanger is provided. A conventional DEC rocket engine has a closed-cycle heat exchanger thermally coupled thereto. The heat exchanger utilizes heat extracted from the engine's fuel circuit to drive the engine's oxidizer turbomachinery.

  12. Dual-fuel natural gas/diesel engines: Technology, performance, and emissions

    Science.gov (United States)

    Turner, S. H.; Weaver, C. S.

    1994-11-01

    An investigation of current dual-fuel natural gas/diesel engine design, performance, and emissions was conducted. The most pressing technological problems associated with dual-fuel engine use were identified along with potential solutions. It was concluded that dual-fuel engines can achieve low NO(sub x) and particulate emissions while retaining fuel-efficiency and BMEP levels comparable to those of diesel engines. The investigation also examined the potential economic impact of dual-fuel engines in diesel-electric locomotives, marine vessels, farm equipment, construction, mining, and industrial equipment, and stand-alone electricity generation systems. Recommendations for further additional funding to support research, development, and demonstration in these applications were then presented.

  13. PERFORMANCE AND EXHAUST GAS EMISSIONS ANALYSIS OF DIRECT INJECTION CNG-DIESEL DUAL FUEL ENGINE

    Directory of Open Access Journals (Sweden)

    RANBIR SINGH

    2012-03-01

    Full Text Available Existing diesel engines are under stringent emission regulation particularly of smoke and particulate matter in their exhaust. Compressed Natural Gas and Diesel dual fuel operation is regarded as one of the best ways to control emissions from diesel engines and simultaneously saving petroleum based diesel fuel. Dual fuel engineis a conventional diesel engine which burn either gaseous fuel or diesel or both at the same time. In the present paper an experimental research was carried out on a laboratory single cylinder, four-stroke variable compression ratio, direct injection diesel engine converted to CNG-Diesel dual fuel mode to analyze the performance and emission characteristics of pure diesel first and then CNG-Diesel dual fuel mode. The measurements were recorded for the compression ratio of 15 and 17.5 at CNG substitution rates of 30% and 60% and varying theload from idle to rated load of 3.5kW in steps of 1 up to 3kW and then to 3.5kW. The results reveal that brake thermal efficiency of dual fuel engine is in the range of 30%-40% at the rated load of 3.5 kW which is 11%-13% higher than pure diesel engine for 30% and 60% CNG substitution rates. This trend is observed irrespective of the compression ratio of the engine. Brake specific fuel consumption of dual fuel engine is found better than pure diesel engine at all engine loads and for both CNG substitution rates. It is found that there is drastic reduction in CO, CO2, HC, NOx and smoke emissions in the exhaust of dual fuel engine at all loads and for 30% and 60% CNG substitution rates by employing some optimum operating conditions set forth for experimental investigations in this study.

  14. The use of low power dual mode nuclear thermal rocket engines to support space exploration missions

    Science.gov (United States)

    Zubrin, Robert M.

    1991-01-01

    The evolution of dual mode concepts is presented, focusing on advantages and problems associated with both low and high temperature dual mode conversion systems. It is concluded that dual mode nuclear thermal rocket (NTR) systems using high temperature Brayton cycle conversion technology offer a high payoff enhancement of conventional NTR, with a comparatively minor increase of technological challenge. It is recommended that NTR engines be designed so that dual mode conversion systems can be attached to them in a modular way, thus enabling the production of electric power on all missions where it is needed.

  15. Study of thermal and emission performance of small gasifier-dual-fuel engine systems

    Energy Technology Data Exchange (ETDEWEB)

    Parikh, P.P.; Bhave, A.G.; Kapse, D.V.; Shashikantha (Indian Inst. of Tech., Bombay (India). Dept. of Mechanical Engineering)

    1989-01-01

    Performance of a downdraft, biomass gasifier-engine system is reported. Two types of diesel (direct injected and indirect injected) engines used in agricultural applications have been operated with the same gasifier system in the producer gas-cum-diesel, dual-fuel mode. The biomass used in these investigations is Subabool (Leucaena leucocephala). The systems have been evaluated with reference to their thermal, power and emission performance levels. Percentage diesel replacement at different loads has been evaluated as a parameter of interest. It was observed that the various performance facets of dual-fuel operation are considerably influenced by the engine design and operating parameters such as the design of the cooling-cleaning system, especially its volume, which is an important parameter determining the level of diesel replacement as well as the power capacity under dual-fuel mode. The low speed engine was found to be more sensitive to the volume of cooling-cleaning system. (author).

  16. One dimensional modeling of a diesel-CNG dual fuel engine

    Science.gov (United States)

    Azman, Putera Adam; Fawzi, Mas; Ismail, Muammar Mukhsin; Osman, Shahrul Azmir

    2017-04-01

    Some of the previous studies have shown that the use of compressed natural gas (CNG) in diesel engines potentially produce engine performance improvement and exhaust gas emission reduction, especially nitrogen oxides, unburned hydrocarbons, and carbon dioxide. On the other hand, there are other researchers who claimed that the use of CNG increases exhaust gas emissions, particularly nitrogen oxides. In this study, a one-dimensional model of a diesel-CNG dual fuel engine was made based on a 4-cylinder 2.5L common rail direct injection diesel engine. The software used is GT-Power, and it was used to analyze the engine performance and exhaust gas emissions of several diesel-CNG dual fuel blend ratios, i.e. 100:0, 90:10, 80:20, 70:30, 60:40 and 50:50. The effect of 100%, 75%, 50% engine loads on the exhaust gas emissions were also studied. The result shows that all diesel-CNG fuel blends produces higher brake torque and brake power at engine speed of 2000-3000 rpm compared with 100% diesel. The 50:50 diesel-CNG blend produces the highest brake torque and brake power, but also has the highest brake specific fuel consumption. As a higher percentage of CNG added to the dual fuel blend, unburned hydrocarbons and carbon monoxide emission increased while carbon dioxide emission decreased. The nitrogen oxides emission concentration is generally unaffected by any change of the dual fuel ratio.

  17. Concept for a LNG Gas Handling System for a Dual Fuel Engine

    Directory of Open Access Journals (Sweden)

    Michael Rachow

    2017-09-01

    Full Text Available Nowadays, ships are using LNG as main engine fuel because based on the facts that LNG has no sulphur content, and its combustion process, LNG produces low NOx content compared to heavy fuel oil and marine diesel oil. LNG is not only produces low gas emission, but may have economic advantages. In the engine laboratory of maritime studies department in Warnemunde, Germany, there is a diesel engine type MAN 6L23/30 A, where the mode operation of these engine would be changed to dual fuel engine mode operation. Therefore, in this thesis, the use dual fuel engine will be compared where it will utilize natural gas and marine diesel oil and select the required components for fuel gas supply system. By conducting the process calculation, engine MAN 6L23/30 A requires the capacity natural gas of 12.908  for 5 days at full load. A concept for LNG supply system would be arranged from storage tank until engine manifold. Germanischer Lloyd and Project Guide of dual fuel engine will be used as a guidelines to develop an optimal design and arrangement which comply with the regulation.

  18. Compressed Biogas-Diesel Dual-Fuel Engine Optimization Study for Ultralow Emission

    Directory of Open Access Journals (Sweden)

    Hasan Koten

    2014-06-01

    Full Text Available The aim of this study is to find out the optimum operating conditions in a diesel engine fueled with compressed biogas (CBG and pilot diesel dual-fuel. One-dimensional (1D and three-dimensional (3D computational fluid dynamics (CFD code and multiobjective optimization code were employed to investigate the influence of CBG-diesel dual-fuel combustion performance and exhaust emissions on a diesel engine. In this paper, 1D engine code and multiobjective optimization code were coupled and evaluated about 15000 cases to define the proper boundary conditions. In addition, selected single diesel fuel (dodecane and dual-fuel (CBG-diesel combustion modes were modeled to compare the engine performances and exhaust emission characteristics by using CFD code under various operating conditions. In optimization study, start of pilot diesel fuel injection, CBG-diesel flow rate, and engine speed were optimized and selected cases were compared using CFD code. CBG and diesel fuels were defined as leading reactants using user defined code. The results showed that significantly lower NOx emissions were emitted under dual-fuel operation for all cases compared to single-fuel mode at all engine load conditions.

  19. Effects of mixing system and pilot fuel quality on diesel-biogas dual fuel engine performance.

    Science.gov (United States)

    Bedoya, Iván Darío; Arrieta, Andrés Amell; Cadavid, Francisco Javier

    2009-12-01

    This paper describes results obtained from CI engine performance running on dual fuel mode at fixed engine speed and four loads, varying the mixing system and pilot fuel quality, associated with fuel composition and cetane number. The experiments were carried out on a power generation diesel engine at 1500 m above sea level, with simulated biogas (60% CH(4)-40% CO(2)) as primary fuel, and diesel and palm oil biodiesel as pilot fuels. Dual fuel engine performance using a naturally aspirated mixing system and diesel as pilot fuel was compared with engine performance attained with a supercharged mixing system and biodiesel as pilot fuel. For all loads evaluated, was possible to achieve full diesel substitution using biogas and biodiesel as power sources. Using the supercharged mixing system combined with biodiesel as pilot fuel, thermal efficiency and substitution of pilot fuel were increased, whereas methane and carbon monoxide emissions were reduced.

  20. An Experimental Investigation of Performance and Emissions of LPG as Dual Fuel in Diesel Engine Generator

    Directory of Open Access Journals (Sweden)

    K. Mohan Kumar

    2014-11-01

    Full Text Available The usage of diesel engine generating set (Gen set increasing day by day where the places without connection to power grid or emergency power supply when the grid fails. Worldwide dual fuel engines are becoming popular because of high performance and low emissions. LPG with diesel is a proven technology in case of vehicles, but in diesel engine power plants it is far so. The proposed work is concentrated on higher load of Diesel Engine Generator with LPG as dual fuel by keeping environmental concern. A test is conducted on performance of engine along with emissions at different proportions of Diesel and LPG including 100% diesel. An experimental set up is made with simple modifications on existing genset to supply LPG as secondary fuel into Diesel.

  1. EFFECT OF INJECTION PRESSURE ON PERFORMANCE AND EMISSIONS OF CNG DIESEL DUAL FUEL ENGINE

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    B.NAGESWARA RAO

    2014-07-01

    Full Text Available A single-cylinder diesel engine has been converted into a dual-fuel engine to operate with natural gas together with a pilot injection of diesel fuel used to ignite the CNG–air charge. The CNG was inducted into the combustion chamber via intake manifold. The engine, operating in dual-fuel mode, has been tested on a wide range of operating conditions spanning different values of engine load at constant speed at different injector opening pressures for the pilot fuel (diesel. For all the tested operating conditions, the effect of CNG and diesel fuel injection pressure, together with the amount of fuel injected during the pilot injection, were analyzed on the engine performance, in terms of brake thermal efficiency and emission levels. An experimental investigation was carried out to find out the effect of injection pressure on performance and emissions of a diesel engine operated with CNG inducted into the engine. Behavior of the dual fuel engine at 10%, 20%, 30%, 40% and 50% substitution of CNG with respect to diesel was examined and compared them at different injection pressures

  2. Tunable dual-wavelength filter and its group delay dispersion in domain-engineered lithium niobate

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    Guang-hao Shao

    2016-12-01

    Full Text Available A tunable dual-wavelength filter is experimentally demonstrated in domain-engineered lithium niobate. Application of an electric field on the y-surfaces of the sample results in the optical axes rotating clockwise and anticlockwise, which makes selective polarization rotation. The quasi phase-matching wavelengths could be adjusted through suitable domain design. A unique dual valley spectrum is obtained in a periodically poled lithium niobate structure with a central defect if the sample is placed between two parallel polarizers. The expected bandwidth could be varied from ∼1 nm to ∼40 nm. Moreover, both the spectral response and group delay dispersion could be engineered.

  3. Tunable dual-wavelength filter and its group delay dispersion in domain-engineered lithium niobate

    Science.gov (United States)

    Shao, Guang-hao; Song, Jing; Ruan, Ya-ping; Cui, Guo-xin; Lu, Yan-qing

    2016-12-01

    A tunable dual-wavelength filter is experimentally demonstrated in domain-engineered lithium niobate. Application of an electric field on the y-surfaces of the sample results in the optical axes rotating clockwise and anticlockwise, which makes selective polarization rotation. The quasi phase-matching wavelengths could be adjusted through suitable domain design. A unique dual valley spectrum is obtained in a periodically poled lithium niobate structure with a central defect if the sample is placed between two parallel polarizers. The expected bandwidth could be varied from ˜1 nm to ˜40 nm. Moreover, both the spectral response and group delay dispersion could be engineered.

  4. Experimental Investigation Of Biogas-Biodiesel Dual Fuel Combustion In A Diesel Engine

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    Ramesha D. K.

    2015-06-01

    Full Text Available This study is an attempt at achieving diesel fuel equivalent performance from diesel engines with maximum substitution of diesel with renewable fuels. In this context the study has been designed to analyze the influence of B20 algae biodiesel as a pilot fuel in a biodiesel biogas dual fuel engine, and results are compared to those of biodiesel and diesel operation at identical engine settings. Experiments were performed at various loads from 0 to 100 % of maximum load at a constant speed of 1500 rpm. In general, B20 algae biodiesel is compatible with diesel in terms of performance and combustion characteristics. Dual fuel mode operation displays lower thermal efficiency and higher fuel consumption than for other fuel modes of the test run across the range of engine loads. Dual fuel mode displayed lower emissions of NOx and Smoke opacity while HC and CO concentrations were considerably higher as compared to other fuels. In dual fuel mode peak pressure and heat release rate were slightly higher compared to diesel and biodiesel mode of operation for all engine loads.

  5. Knock characteristics of dual-fuel combustion in diesel engines using natural gas as primary fuel

    Indian Academy of Sciences (India)

    O M I Nwafor

    2002-06-01

    This paper investigates the combustion knock characteristics of diesel engines running on natural gas using pilot injection as means of initiating combustion. The diesel engines knock under normal operating conditions but the knock referred to in this paper is an objectionable one. In the dual-fuel combustion process we have the ignition stage followed by the combustion stage. There are three types of knock: diesel knock, spark knock and knock due to secondary ignition delay of the primary fuel (erratic knock). Several factors have been noted to feature in defining knock characteristics of dual-fuel engines that include ignition delay, pilot quantity, engine load and speed, turbulence and gas flow rate.

  6. Cyclic Combustion Variations in Dual Fuel Partially Premixed Pilot-Ignited Natural Gas Engines

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasan, K. K. [Mississippi State Univ., MS (United States). Dept. of Mechanical Engineering; Krishnan, S. R. [Mississippi State Univ., MS (United States). Dept. of Mechanical Engineering; Qi, Y. [Caterpillar, Inc., Peoria, IL (United States)

    2012-05-09

    Dual fuel pilot ignited natural gas engines are identified as an efficient and viable alternative to conventional diesel engines. This paper examines cyclic combustion fluctuations in conventional dual fuel and in dual fuel partially premixed low temperature combustion (LTC). Conventional dual fueling with 95% (energy basis) natural gas (NG) substitution reduces NOx emissions by almost 90%t relative to straight diesel operation; however, this is accompanied by 98% increase in HC emissions, 10 percentage points reduction in fuel conversion efficiency (FCE) and 12 percentage points increase in COVimep. Dual fuel LTC is achieved by injection of a small amount of diesel fuel (2-3 percent on an energy basis) to ignite a premixed natural gas₋air mixture to attain very low NOx emissions (less than 0.2 g/kWh). Cyclic variations in both combustion modes were analyzed by observing the cyclic fluctuations in start of combustion (SOC), peak cylinder pressures (Pmax), combustion phasing (Ca50), and the separation between the diesel injection event and Ca50 (termed "relative combustion phasing" ). For conventional dual fueling, as % NG increases, Pmax decreases, SOC and Ca50 are delayed, and cyclic variations increase. For dual fuel LTC, as diesel injection timing is advanced from 20° to 60° BTDC, the relative combustion phasing is identified as an important combustion parameter along with SoC, Pmax, and CaPmax. For both combustion modes, cyclic variations were characterized by alternating slow and fast burn cycles, especially at high %NG and advanced injection timings. Finally, heat release return maps were analyzed to demonstrate thermal management strategies as an effective tool to mitigate cyclic combustion variations, especially in dual fuel LTC.

  7. Comparison of Propane and Methane Performance and Emissions in a Turbocharged Direct Injection Dual Fuel Engine

    Energy Technology Data Exchange (ETDEWEB)

    Gibson, C. M.; Polk, A. C.; Shoemaker, N. T.; Srinivasan, K. K.; Krishnan, S. R.

    2011-01-01

    With increasingly restrictive NO x and particulate matter emissions standards, the recent discovery of new natural gas reserves, and the possibility of producing propane efficiently from biomass sources, dual fueling strategies have become more attractive. This paper presents experimental results from dual fuel operation of a four-cylinder turbocharged direct injection (DI) diesel engine with propane or methane (a natural gas surrogate) as the primary fuel and diesel as the ignition source. Experiments were performed with the stock engine control unit at a constant speed of 1800 rpm, and a wide range of brake mean effective pressures (BMEPs) (2.7-11.6 bars) and percent energy substitutions (PESs) of C 3 H 8 and CH 4. Brake thermal efficiencies (BTEs) and emissions (NO x, smoke, total hydrocarbons (THCs), CO, and CO 2) were measured. Maximum PES levels of about 80-95% with CH 4 and 40-92% with C 3 H 8 were achieved. Maximum PES was limited by poor combustion efficiencies and engine misfire at low loads for both C 3 H 8 and CH 4, and the onset of knock above 9 bar BMEP for C 3 H 8. While dual fuel BTEs were lower than straight diesel BTEs at low loads, they approached diesel BTE values at high loads. For dual fuel operation, NO x and smoke reductions (from diesel values) were as high as 66-68% and 97%, respectively, but CO and THC emissions were significantly higher with increasing PES at all engine loads

  8. Comparison of performance of biodiesels of mahua oil and gingili oil in dual fuel engine

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    Nadar Kapilan N.

    2008-01-01

    Full Text Available In this work, an experimental work was carried out to compare the performance of biodiesels made from non edible mahua oil and edible gingili oil in dual fuel engine. A single cylinder diesel engine was modified to work in dual fuel mode and liquefied petroleum gas was used as primary fuel. Biodiesel was prepared by transesterification process and mahua oil methyl ester (MOME and gingili oil methyl ester (GOME were used as pilot fuels. The viscosity of MOME is slightly higher than GOME. The dual fuel engine runs smoothly with MOME and GOME. The test results show that the performance of the MOME is close to GOME, at the pilot fuel quantity of 0.45 kg/h and at the advanced injection timing of 30 deg bTDC. Also it is observed that the smoke, carbon monoxide and unburnt hydro carbon emissions of GOME lower than the MOME. But the GOME results in slightly higher NOx emissions. From the experimental results it is concluded that the biodiesel made from mahua oil can be used as a substitute for diesel in dual fuel engine.

  9. Knock prediction for dual fuel engines by using a simplified combustion model

    Institute of Scientific and Technical Information of China (English)

    费少梅; 刘震涛; 严兆大

    2003-01-01

    The present work used a methane-air mixture chemical kinetics scheme consisting of 119 elementary reaction steps and 41 chemical species to develop a simplified combustion model for prediction of the knock in dual fuel engines. Calculated values by the model for natural gas operation showed good agreement with corresponding experimental values over a broad range of operating conditions.

  10. Dual-Scale Polymeric Constructs as Scaffolds for Tissue Engineering

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    Federica Chiellini

    2011-03-01

    Full Text Available This research activity was aimed at the development of dual-scale scaffolds consisting of three-dimensional constructs of aligned poly(ε-caprolactone (PCL microfilaments and electrospun poly(lactic-co-glycolic acid (PLGA fibers. PCL constructs composed by layers of parallel microsized filaments (0/90° lay-down pattern, with a diameter of around 365 μm and interfilament distance of around 191 μm, were produced using a melt extrusion-based additive manufacturing technique. PLGA electrospun fibers with a diameter of around 1 μm were collected on top of the PCL constructs with different thicknesses, showing a certain degree of alignment. Cell culture experiments employing the MC3T3 murine preosteoblast cell line showed good cell viability and adhesion on the dual-scale scaffolds. In particular, the influence of electrospun fibers on cell morphology and behavior was evident, as well as in creating a structural bridging for cell colonization in the interfilament gap.

  11. Thermodynamic Analysis of Dual-Mode Scramjet Engine Operation and Performance

    Science.gov (United States)

    Riggins, David; Tacket, Regan; Taylor, Trent; Auslender, Aaron

    2006-01-01

    Recent analytical advances in understanding the performance continuum (the thermodynamic spectrum) for air-breathing engines based on fundamental second-law considerations have clarified scramjet and ramjet operation, performance, and characteristics. Second-law based analysis is extended specifically in this work to clarify and describe the performance characteristics for dual-mode scramjet operation in the mid-speed range of flight Mach 4 to 7. This is done by a fundamental investigation of the complex but predictable interplay between heat release and irreversibilities in such an engine; results demonstrate the flow and performance character of the dual mode regime and of dual mode transition behavior. Both analytical and computational (multi-dimensional CFD) studies of sample dual-mode flow-fields are performed in order to demonstrate the second-law capability and performance and operability issues. The impact of the dual-mode regime is found to be characterized by decreasing overall irreversibility with increasing heat release, within the operability limits of the system.

  12. Prediction models for performance and emissions of a dual fuel CI engine using ANFIS

    Indian Academy of Sciences (India)

    A Adarsh Rai; P Srinivasa Pai; B R Shrinivasa Rao

    2015-04-01

    Dual fuel engines are being used these days to overcome shortage of fossil fuels and fulfill stringent exhaust gas emission regulations. They have several advantages over conventional diesel engines. In this context, this paper makes use of experimental results obtained from a dual fuel engine for developing models to predict performance and emission parameters. Conventional modelling efforts to understand the relationships between the input and the output variables, requires thermodynamic analysis which is complex and time consuming. As a result, efforts have been made to use artificial intelligence modelling techniques like fuzzy logic, Artificial Neural Network (ANN), Genetic Algorithm (GA), etc. This paper uses a neuro fuzzy modelling technique, Adaptive Neuro Fuzzy Inference System (ANFIS) for developing prediction models for performance and emission parameter of a dual fuel engine. Percentage load, percentage Liquefied Petroleum Gas (LPG) and Injection Timing (IT) have been used as input parameters, whereas output parameters include Brake Specific Energy Consumption (BSEC), Brake Thermal Efficiency (BTE), Exhaust Gas Temperature (EGT) and smoke. In order to further improve the prediction accuracy of the model, GA has been used to optimize ANFIS. GA optimized ANFIS gives higher prediction accuracy of more than 90% for all parameters except for smoke, where there is a substantial improvement from 46.67% to 73.33%, when compared to conventional ANFIS model.

  13. IMPROVEMENT OF PERFORMANCE OF DUAL FUEL ENGINE OPERATED AT PART LOAD

    Directory of Open Access Journals (Sweden)

    N. Kapilan

    2010-12-01

    Full Text Available Rising petroleum prices, an increasing threat to the environment from exhaust emissions, global warming and the threat of supply instabilities has led to the choice of inedible Mahua oil (MO as one of the main alternative fuels to diesel oil in India. In the present work, MO was converted into biodiesel by transesterification using methanol and sodium hydroxide. The cost of Mahua oil biodiesel (MOB is higher than diesel. Hence liquefied petroleum gas (LPG, which is one of the cheapest gaseous fuels available in India, was fumigated along with the air to reduce the operating cost and to reduce emissions. The dual fuel engine resulted in lower efficiency and higher emissions at part load. Hence in the present work, the injection time was varied and the performance of the dual fuel engine was studied. From the engine tests, it is observed that an advanced injection time results in higher efficiency and lower emissions. Hence, advancing the injection timing is one of the ways of increasing the efficiency of LPG+MOB dual fuel engine operated at part load.

  14. Investigation on utilization of biogas and Karanja oil biodiesel in dual fuel mode in a single cylinder DI diesel engine

    Directory of Open Access Journals (Sweden)

    Bhabani Prasanna Pattanaik, Chandrakanta Nayak, Basanta Kumar Nanda

    2013-01-01

    Full Text Available In this work, experiments were performed on a single cylinder DI diesel engine by using bio-gas as a primary fuel and Karanja oil biodiesel and diesel oil as secondary fuels in dual fuel operation. The experiments were performed to measure performance parameters i.e. (brake specific fuel consumption, brake thermal efficiency and exhaust gas temperature and emission parameters such as carbon monoxide, carbon dioxide, nitrogen oxide unburned hydro carbon and smoke etc. at different load conditions. For the dual-fuel system, the intake system of the test engine was modified to convert into biogas and biodiesel of a dual-fueled combustion engine. Biogas was injected during the intake process by gas injectors. The study showed that, the engine performance parameters like BP, BTE and EGT gradually increase with increase in engine load for all test conditions using both pilot fuels diesel and KOBD. However, the BSFC of the engine showed decreasing slope with increase in engine load for all test conditions. Above 40% engine load the BSFC values for all test fuels are very close to each other. The engine emission analysis showed that the CO2, CO and NOx emissions increase with increase in engine load for both single and dual fuel mode operation using both pilot fuels. The NOx concentration of exhaust gases in dual fuel mode is superior than that of single mode.

  15. Investigation on utilization of biogas and Karanja oil biodiesel in dual fuel mode in a single cylinder DI diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Prasanna Pattanaik, Bhabani; Nayak, Chandrakanta [Department of Mechanical Eng., Gandhi Institute for Technological Advancement, Madanpur, Bhubaneswar - 752054, Odisha (India); Kumar Nanda, Basanta [Department of Mechanical Eng., Maharaja Institute of Technology, Bhubaneswar, Odisha (India)

    2013-07-01

    In this work, experiments were performed on a single cylinder DI diesel engine by using bio-gas as a primary fuel and Karanja oil biodiesel and diesel oil as secondary fuels in dual fuel operation. The experiments were performed to measure performance parameters i.e. (brake specific fuel consumption, brake thermal efficiency and exhaust gas temperature) and emission parameters such as carbon monoxide, carbon dioxide, nitrogen oxide unburned hydro carbon and smoke etc. at different load conditions. For the dual-fuel system, the intake system of the test engine was modified to convert into biogas and biodiesel of a dual-fueled combustion engine. Biogas was injected during the intake process by gas injectors. The study showed that, the engine performance parameters like BP, BTE and EGT gradually increase with increase in engine load for all test conditions using both pilot fuels diesel and KOBD. However, the BSFC of the engine showed decreasing slope with increase in engine load for all test conditions. Above 40% engine load the BSFC values for all test fuels are very close to each other. The engine emission analysis showed that the CO2, CO and NOx emissions increase with increase in engine load for both single and dual fuel mode operation using both pilot fuels. The NOx concentration of exhaust gases in dual fuel mode is superior than that of single mode.

  16. Dual-Fuel Combustion for Future Clean and Efficient Compression Ignition Engines

    Directory of Open Access Journals (Sweden)

    Jesús Benajes

    2016-12-01

    Full Text Available Stringent emissions limits introduced for internal combustion engines impose a major challenge for the research community. The technological solution adopted by the manufactures of diesel engines to meet the NOx and particle matter values imposed in the EURO VI regulation relies on using selective catalytic reduction and particulate filter systems, which increases the complexity and cost of the engine. Alternatively, several new combustion modes aimed at avoiding the formation of these two pollutants by promoting low temperature combustion reactions, are the focus of study nowadays. Among these new concepts, the dual-fuel combustion mode known as reactivity controlled compression ignition (RCCI seems more promising because it allows better control of the combustion process by means of modulating the fuel reactivity depending on the engine operating conditions. The present experimental work explores the potential of different strategies for reducing the energy losses with RCCI in a single-cylinder research engine, with the final goal of providing the guidelines to define an efficient dual-fuel combustion system. The results demonstrate that the engine settings combination, piston geometry modification, and fuel properties variation are good methods to increase the RCCI efficiency while maintaining ultra-low NOx and soot emissions for a wide range of operating conditions.

  17. Application of Alcohols to Dual - Fuel Feeding the Spark-Ignition and Self-Ignition Engines

    Directory of Open Access Journals (Sweden)

    Stelmasiak Zdzisław

    2014-10-01

    Full Text Available This paper concerns analysis of possible use of alcohols for the feeding of self - ignition and spark-ignition engines operating in a dual- fuel mode, i.e. simultaneously combusting alcohol and diesel oil or alcohol and petrol. Issues associated with the requirements for application of bio-fuels were presented with taking into account National Index Targets, bio-ethanol production methods and dynamics of its production worldwide and in Poland. Te considerations are illustrated by results of the tests on spark- ignition and self- ignition engines fed with two fuels: petrol and methanol or diesel oil and methanol, respectively. Te tests were carried out on a 1100 MPI Fiat four- cylinder engine with multi-point injection and a prototype collector fitted with additional injectors in each cylinder. Te other tested engine was a SW 680 six- cylinder direct- injection diesel engine. Influence of a methanol addition on basic operational parameters of the engines and exhaust gas toxicity were analyzed. Te tests showed a favourable influence of methanol on combustion process of traditional fuels and on some operational parameters of engines. An addition of methanol resulted in a distinct rise of total efficiency of both types of engines at maintained output parameters (maximum power and torque. In the same time a radical drop in content of hydrocarbons and nitrogen oxides in exhaust gas was observed at high shares of methanol in feeding dose of ZI (petrol engine, and 2-3 fold lower smokiness in case of ZS (diesel engine. Among unfavourable phenomena, a rather insignificant rise of CO and NOx content for ZI engine, and THC and NOx - for ZS engine, should be numbered. It requires to carry out further research on optimum control parameters of the engines. Conclusions drawn from this work may be used for implementation of bio-fuels to feeding the combustion engines.

  18. Fracture Failure Analysis of Fuel Pump Transmission Shaft of Dual-Fuel Engine

    Directory of Open Access Journals (Sweden)

    Chen Pei-hong

    2017-01-01

    Full Text Available NTS6ZLCz-129 dual-fuel turbocharged and intercooled engine durability test at 1000h, fuel pump shaft fractured. Fracture analysis, chemical analysis, microstructure examination and finite element stress analysis were carried out on the fractured shaft. The analysis result showed that the shaft fracture cause is forging fold. By improving the forging process, the forging fold was solved, and the durability test can be carried out smoothly.

  19. Dual-frequency Eddy Current Non-destructive Detection of Fatigue Cracks in Compressor Discs of Aero Engines

    National Research Council Canada - National Science Library

    B. Sasi; B.P.C. Rao; T. Jayakumar

    2004-01-01

    ... related aircraft components. This paper discusses a dual-frequency eddy current testing procedure developed for inspection of compressor discs of aero engines for detecting fatigue cracks with high sensitivity and reliability...

  20. Simulation of Cycle-to-Cycle Variation in Dual-Fuel Engines

    KAUST Repository

    Jaasim, Mohammed

    2017-03-13

    Standard practices of internal combustion (IC) engine experiments are to conduct the measurements of quantities averaged over a large number of cycles. Depending on the operating conditions, the cycle-to-cycle variation (CCV) of quantities, such as the indicated mean effective pressure (IMEP) are observed at different levels. Accurate prediction of CCV in IC engines is an important but challenging task. Computational fluid dynamics (CFD) simulations using high performance computing (HPC) can be used effectively to visualize such 3D spatial distributions. In the present study, a dual fuel large engine is considered, with natural gas injected into the manifold accompanied with direct injection of diesel pilot fuel to trigger ignition. Multiple engine cycles in 3D are simulated in series as in the experiments to investigate the potential of HPC based high fidelity simulations to accurately capture the cycle to cycle variation in dual fuel engines. Open cycle simulations are conducted to predict the combined effect of the stratification of fuel-air mixture, temperature and turbulence on the CCV of pressure. The predicted coefficient of variation (COV) of pressure compared to the results from closed cycle simulations and the experiments.

  1. Particulate Matter Emission from Dual Fuel Diesel Engine Fuelled with Natural Gas

    Directory of Open Access Journals (Sweden)

    Stelmasiak Zdzisław

    2017-06-01

    Full Text Available The paper presents the results of examination of particulate matter emission from the Diesel engine FPT 1.3 MJT simultaneously fuelled with diesel oil and natural gas CNG. The basic premise for engine adaptation was the addition of a small amount of CNG to reduce exhaust gas opacity and particulate matter emission. At this assumption, diesel oil remained the basic fuel, with contribution amounting to 0,70-0,85 of total energy delivered to the engine. The dual fuel engine was examined using an original controller installed in the Diesel engine FPT 1.3 MJT which controlled the diesel fuel dose. The dose of the injected natural gas was controlled by changing the opening time of gas injectors at constant pressure in the gas collector. The examined issues included the exhaust gas opacity, and the total number and fractional distribution of the emitted particles. The measurements were performed at twenty selected measuring points corresponding to the New European Driving Cycle (NEDC test. The performed tests have demonstrated a positive effect of gas addition on exhaust gas opacity and particulate matter emission. Depending on test conditions, the exhaust gas opacity was reduced by 10÷92%, and the total number of particles by 30÷40%. The performed tests have revealed that a small addition of gas can reduce the load of the DPF filter, extend its lifetime, and increase engine reliability. Longer time intervals between successive DPF filter regenerations improve ecological properties of the engine.

  2. Dual fuel mode operation in diesel engines using renewable fuels: Rubber seed oil and coir-pith producer gas

    Energy Technology Data Exchange (ETDEWEB)

    Ramadhas, A.S.; Jayaraj, S.; Muraleedharan, C. [Department of Mechanical Engineering, National Institute of Technology Calicut, Calicut-673601 (India)

    2008-09-15

    Partial combustion of biomass in the gasifier generates producer gas that can be used as supplementary or sole fuel for internal combustion engines. Dual fuel mode operation using coir-pith derived producer gas and rubber seed oil as pilot fuel was analyzed for various producer gas-air flow ratios and at different load conditions. The engine is experimentally optimized with respect to maximum pilot fuel savings in the dual fuel mode operation. The performance and emission characteristics of the dual fuel engine are compared with that of diesel engine at different load conditions. Specific energy consumption in the dual-fuel mode of operation with oil-coir-pith operation is found to be in the higher side at all load conditions. Exhaust emission was found to be higher in the case of dual fuel mode of operation as compared to neat diesel/oil operation. Engine performance characteristics are inferior in fully renewable fueled engine operation but it suitable for stationary engine application, particularly power generation. (author)

  3. Micro generation of electricity with gasification gas in a engine generator in dual mode; Microgeracao de eletricidade com gas de gaseificacao num motor gerador dual

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Marcelo Jose da; Souza, Samuel Nelson Melegari de; Souza, Abel Alves de; Ricieri, Reinaldo P. [Universidade Estadual do Oeste do Parana (UNIOESTE), Cascavel, PE (Brazil)], E-mail: marcelo_js07@hotmail.com

    2010-07-01

    Among the alternatives to the increase of world energy demand the use of biomass as energy source is one of the most promising as it contributes to reducing emissions of carbon dioxide in the atmosphere. Gasification is a process technology of biomass energy in a gaseous biofuel. The fuel gas got a low calorific value that can be used in diesel engine in dual mode for power generation in isolated communities. This study aimed to evaluate the reduction in the consumption of oil diesel an engine generator, using gas from gasification of wood. The engine generator brand used, it was a BRANCO, with direct injection power of 10 hp and mated to an electric generator 5,5 kW. The fuel gas was produced in a gasifier type co-current. The engine generator was put on load system from 0.5 kW to 3.5 kW through electric bank of heaters. For the oil diesel savings, the gas was injected mixed with intake air, as the oil diesel was normally injected by the injector of the engine (motor dual). The consumption od diesel was measured diesel by means of a precision scale. It was concluded that the engine converted to dual mode when using the gas for the gasification of wood showed a decrease in diesel consumption by up to 57%. (author)

  4. Improving the performance and fuel consumption of dual chamber stratified charge spark ignition engines

    Energy Technology Data Exchange (ETDEWEB)

    Sorenson, S.C.; Pan, S.S.; Bruckbauer, J.J.; Gehrke, G.R.

    1979-09-01

    A combined experimental and theoretical investigation of the nature of the combustion processes in a dual chamber stratified charge spark ignition engine is described. This work concentrated on understanding the mixing process in the main chamber gases. A specially constructed single cylinder engine was used to both conduct experiments to study mixing effects and to obtain experimental data for the validation of the computer model which was constructed in the theoretical portion of the study. The test procedures are described. Studies were conducted on the effect of fuel injection timing on performance and emissions using the combination of orifice size and prechamber to main chamber flow rate ratio which gave the best overall compromise between emissions and performance. In general, fuel injection gave slightly higher oxides of nitrogen, but considerably lower hydrocarbon and carbon monoxide emissions than the carbureted form of the engine. Experiments with engine intake port redesign to promote swirl mixing indicated a substantial increase in the power output from the engine and, that an equivalent power levels, the nitric oxide emissions are approximately 30% lower with swirl in the main chamber than without swirl. The development of a computer simulation of the combustion process showed that a one-dimensional combustion model can be used to accurately predict trends in engine operation conditions and nitric oxide emissions even though the actual flame in the engine is not completely one-dimensional, and that a simple model for mixing of the main chamber and prechamber intake gases at the start of compression proved adequate to explain the effects of swirl, ignition timing, overall fuel air ratio, volumetric efficiency, and variations in prechamber air fuel ratio and fuel rate percentage on engine power and nitric oxide emissions. (LCL)

  5. Engineering aesthetics and aesthetic ergonomics: theoretical foundations and a dual-process research methodology.

    Science.gov (United States)

    Liu, Yili

    Although industrial and product designers are keenly aware of the importance of design aesthetics, they make aesthetic design decisions largely on the basis of their intuitive judgments and "educated guesses". Whilst ergonomics and human factors researchers have made great contributions to the safety, productivity, ease-of-use, and comfort of human-machine-environment systems, aesthetics is largely ignored as a topic of systematic scientific research in human factors and ergonomics. This article discusses the need for incorporating the aesthetics dimension in ergonomics and proposes the establishment of a new scientific and engineering discipline that we can call "engineering aesthetics". This discipline addresses two major questions: How do we use engineering and scientific methods to study aesthetics concepts in general and design aesthetics in particular? How do we incorporate engineering and scientific methods in the aesthetic design and evaluation process? This article identifies two special features that distinguish aesthetic appraisal of products and system designs from aesthetic appreciation of art, and lays out a theoretical foundation as well as a dual-process research methodology for "engineering aesthetics". Sample applications of this methodology are also described.

  6. Improvement performance and emissions in a diesel engine dual-fueled with natural gas; Tennen gas dual fuel diesel kikan no seino haishutsu gas tokusei no kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, S.; Okamoto, T.; Kusaka, J.; Daisho, Y.; Kihara, R.; Saito, T. [Waseda University, Tokyo (Japan)

    1997-10-01

    This paper deals with a study on combustion and emission characteristics of a direct injection diesel engine dual-fueled with natural gas. Dual fueling systems tend to emit high unburned fuel especially at low load, resulting in a decreased thermal efficiency. This is because natural gas-air mixtures are too lean for flame to propagate under low load conditions. Intake charge heating and uncooled EGR are very useful to improve emissions and thermal efficiency at low load. Such favorable effects are supported by NO kinetic simulations. 2 refs., 13 figs.

  7. Fault Tree Analysis of Fire and Explosion Accidents for Dual Fuel (Diesel/Natural Gas) Ship Engine Rooms

    Institute of Scientific and Technical Information of China (English)

    Yifeng Guan; Jie Zhao; Tengfei Shiand Peipei Zhu

    2016-01-01

    In recent years, China’s increased interest in environmental protection has led to a promotion of energy-efficient dual fuel (diesel/natural gas) ships in Chinese inland rivers. A natural gas as ship fuel may pose dangers of fire and explosion if a gas leak occurs. If explosions or fires occur in the engine rooms of a ship, heavy damage and losses will be incurred. In this paper, a fault tree model is presented that considers both fires and explosions in a dual fuel ship;in this model, dual fuel engine rooms are the top events. All the basic events along with the minimum cut sets are obtained through the analysis.The primary factors that affect accidents involving fires and explosions are determined by calculating the degree of structure importance of the basic events.According to these results, corresponding measures are proposed to ensure and improve the safety and reliability of Chinese inland dual fuel ships.

  8. Fault tree analysis of fire and explosion accidents for dual fuel (diesel/natural gas) ship engine rooms

    Science.gov (United States)

    Guan, Yifeng; Zhao, Jie; Shi, Tengfei; Zhu, Peipei

    2016-09-01

    In recent years, China's increased interest in environmental protection has led to a promotion of energy-efficient dual fuel (diesel/natural gas) ships in Chinese inland rivers. A natural gas as ship fuel may pose dangers of fire and explosion if a gas leak occurs. If explosions or fires occur in the engine rooms of a ship, heavy damage and losses will be incurred. In this paper, a fault tree model is presented that considers both fires and explosions in a dual fuel ship; in this model, dual fuel engine rooms are the top events. All the basic events along with the minimum cut sets are obtained through the analysis. The primary factors that affect accidents involving fires and explosions are determined by calculating the degree of structure importance of the basic events. According to these results, corresponding measures are proposed to ensure and improve the safety and reliability of Chinese inland dual fuel ships.

  9. Performance and Exhaust Emissions in a Natural-Gas Fueled Dual-Fuel Engine

    Science.gov (United States)

    Shioji, Masahiro; Ishiyama, Takuji; Ikegami, Makoto; Mitani, Shinichi; Shibata, Hiroaki

    In order to establish the optimum fueling in a natural gas fueled dual fuel engine, experiments were done for some operational parameters on the engine performances and the exhaust emissions. The results show that the pilot fuel quantity should be increased and its injection timing should be advanced to suppress unburned hydrocarbon emission in the middle and low output range, while the quantity should be reduced and the timing retarded to avoid onset of knock at high loads. Unburned hydrocarbon emission and thermal efficiency are improved by avoiding too lean natural gas mixture by restricting intake charge air. However, the improvement is limited because the ignition of pilot fuel deteriorates with excessive throttling. It is concluded that an adequate combination of throttle control and equivalence ratio ensures low hydrocarbon emission and the thermal efficiency comparable to diesel operation.

  10. Application of jatropha oil and biogas in a dual fuel engine for rural electrification

    Energy Technology Data Exchange (ETDEWEB)

    Kerkhof, E.

    2008-06-15

    In this thesis, the technical feasibility of using jatropha oil and biogas for dual fuel generators is investigated. This technology could be used for electricity generation in rural areas in developing countries. The use of jatropha oil and biogas is considered a sustainable energy supply, when both fuels are produced locally. The local production of fuel and generation of electricity could result in economic development and poverty reduction. In order to investigate the technical feasibility, a parameter study is performed, an experimental set-up is constructed and experiments are carried out. Three performance parameters are investigated: thermal efficiency, because it is a direct measure for fuel efficiency; volumetric efficiency, because it is a measure for power output; and air-excess ratio, because it influences particulate emissions and HC emissions. The parameter study is conducted, to predict the effect of dual fuel operation, by deriving expressions for the performance parameters. The experiments are carried out to assess the effect of dual fuel operation on performance and to find the operation limits (smoke limit and knock limit). Experiments are carried out on a 12 kW diesel generator set. The jatropha oil that is used is pure oil. Biogas mainly consists of methane and carbon dioxide. Simulated, bottled, biogas of different quality is used (i.e. CH4/CO2 ratios). Pure methane is also tested as gaseous fuel. Gas is added to the inlet air with a venturi. The design of the venturi limited the gas flow; consequently the maximum heat release fraction of methane was 80% for pure methane and approximately 70% for biogas. Tests were performed at 6, 8 and 10 kW load. The engine showed a thermal efficiency characteristic for pure jatropha oil operation, which is expected for a diesel generator. The characteristic for jatropha oil did not deviate from that of diesel. At full load, thermal efficiency is approximately 32%. Under dual fuel operation, with biogas, at

  11. Performance and Emissions of a Small Compression Ignition Engine Run on Dual-fuel Mode (Diesel-Raw biogas)

    Science.gov (United States)

    Ambarita, H.; Sinulingga, E. P.; Nasution, M. KM; Kawai, H.

    2017-03-01

    In this work, a compression ignition (CI) engine is tested in dual-fuel mode (Diesel-Raw biogas). The objective is to examine the performance and emission characteristics of the engine when some of the diesel oil is replaced by biogas. The specifications of the CI engine are air cooled single horizontal cylinder, four strokes, and maximum output power of 4.86 kW. It is coupled with a synchronous three phase generator. The load, engine revolution, and biogas flow rate are varied from 600 W to 1500 W, 1000 rpm to 1500 rpm, 0 to 6 L/minute, respectively. The electric power, specific fuel consumption, thermal efficiency, gas emission, and diesel replacement ratio are analyzed. The results show that there is no significant difference of the power resulted by CI run on dual-fuel mode in comparison with pure diesel mode. However, the specific fuel consumption and efficiency decrease significantly as biogas flow rate increases. On the other hand, emission of the engine on dual-fuel mode is better. The main conclusion can be drawn is that CI engine without significant modification can be operated perfectly in dual-fuel mode and diesel oil consumption can be decreased up to 87.5%.

  12. Co-electrospun dual scaffolding system with potential for muscle-tendon junction tissue engineering.

    Science.gov (United States)

    Ladd, Mitchell R; Lee, Sang Jin; Stitzel, Joel D; Atala, Anthony; Yoo, James J

    2011-02-01

    Tissue engineering has had successes developing single tissue types, but there is a need for methods that will allow development of composite tissues. For instance, muscle-tendon junctions (MTJ) require a seamless interface to allow force transfer from muscle to tendon. One challenge in engineering MTJs is designing a continuous scaffold suitable for both tissue types. We aimed to create a dual scaffold that exhibits regional mechanical property differences that mimic the trends seen in native MTJ. Poly(ε-caprolactone)/collagen and poly(l-lactide)/collagen were co-electrospun onto opposite ends of a mandrel to create a scaffold with 3 regions. Scaffolds were characterized with scanning electron microscopy, tensile testing (uniaxial, cyclic, and video strain), for cytocompatibility using MTS, and seeded with C2C12 myoblasts and NIH3T3 fibroblasts. Native porcine diaphragm MTJs were also analyzed with video strain for comparison. Integrated scaffolds were created with fiber diameters from 452-549 nm. Scaffolds exhibited regional variations in mechanical properties with moduli from 4.490-27.62 MPa and generally withstood cyclic testing, although with hysteresis. Video analysis showed scaffold strain profiles exhibited similar trends to native MTJ. The scaffolds were cytocompatible and accommodated cell attachment and myotube formation. The properties engineered into these scaffolds make them attractive candidates for tissue engineering of MTJs. 2010 Elsevier Ltd. All rights reserved.

  13. Numerical and Experimental Investigation of Combustion and Knock in a Dual Fuel Gas/Diesel Compression Ignition Engine

    OpenAIRE

    Gharehghani, A.; S. M. Mirsalim; S. A. Jazayeri

    2012-01-01

    Conventional compression ignition engines can easily be converted to a dual fuel mode of operation using natural gas as main fuel and diesel oil injection as pilot to initiate the combustion. At the same time, it is possible to increase the output power by increasing the diesel oil percentage. A detailed performance and combustion characteristic analysis of a heavy duty diesel engine has been studied in dual fuel mode of operation where natural gas is used as the main fuel and diesel oil as p...

  14. Application of neural network in the study of combustion rate of natural gas/diesel dual fuel engine.

    Science.gov (United States)

    Yan, Zhao-Da; Zhou, Chong-Guang; Su, Shi-Chuan; Liu, Zhen-Tao; Wang, Xi-Zhen

    2003-01-01

    In order to predict and improve the performance of natural gas/diesel dual fuel engine (DFE), a combustion rate model based on forward neural network was built to study the combustion process of the DFE. The effect of the operating parameters on combustion rate was also studied by means of this model. The study showed that the predicted results were good agreement with the experimental data. It was proved that the developed combustion rate model could be used to successfully predict and optimize the combustion process of dual fuel engine.

  15. Application of neural network in the study of combustion rate of natural gas/diesel dual fuel engine

    Institute of Scientific and Technical Information of China (English)

    严兆大; 周重光; 苏石川; 刘震涛; 王希珍

    2003-01-01

    In order to predict and improve the performance of natural gas/diesel dual fuel engine (DFE), a combustion rate model based on forward neural network was built to study the combustion process of the DFE. The effect of the operating parameters on combustion rate was also studied by means of this model. The study showed that the predicted results were good agreement with the experimental data. It was proved that the developed combustion rate model could be used to successfully predict and optimize the combustion process of dual fuel engine.

  16. Application of neural network in the study of combustion rate of natural gas/diesel dual fuel engine

    Institute of Scientific and Technical Information of China (English)

    严兆大; 周重光; 苏石川; 刘震涛; 王希珍

    2003-01-01

    In order to predict and improve the performance of matural gas/diesel dual fuel engine(DFE),a combustion rate model based on forward meural network was built to study the combustion process of the DFE.The effect of the operating parameters on combustion rate was also studied by means of this model.The study showed that the predicted results were good agreement with the experimental data.It was proved that the de-veloped combustion rate model could be used to successfully predict and optimize the combustion process of dual fuel engine.

  17. Thermal design of a natural gas - diesel dual fuel turbocharged V18 engine for ship propulsion and power plant applications

    Science.gov (United States)

    Douvartzides, S.; Karmalis, I.

    2016-11-01

    A detailed method is presented on the thermal design of a natural gas - diesel dual fuel internal combustion engine. An 18 cylinder four stroke turbocharged engine is considered to operate at a maximum speed of 500 rpm for marine and power plant applications. Thermodynamic, heat transfer and fluid flow phenomena are mathematically analyzed to provide a real cycle analysis together with a complete set of calculated operation conditions, power characteristics and engine efficiencies. The method is found to provide results in close agreement to published data for the actual performance of similar engines such as V18 MAN 51/60DF.

  18. Numerical investigation of the impact of gas composition on the combustion process in a dual-fuel compression-ignition engine

    NARCIS (Netherlands)

    Mikulski, M.; Wierzbicki, S.

    2016-01-01

    This study discusses the model of operation of a dual-fuel compression-ignition engine, powered by gaseous fuel with an initial dose of diesel fuel as the ignition inhibitor. The study used a zero-dimensional multiphase mathematical model of a dual-fuel engine to simulate the impact of enhancing

  19. Numerical investigation of the impact of gas composition on the combustion process in a dual-fuel compression-ignition engine

    NARCIS (Netherlands)

    Mikulski, M.; Wierzbicki, S.

    2016-01-01

    This study discusses the model of operation of a dual-fuel compression-ignition engine, powered by gaseous fuel with an initial dose of diesel fuel as the ignition inhibitor. The study used a zero-dimensional multiphase mathematical model of a dual-fuel engine to simulate the impact of enhancing Nat

  20. An experimental assessment on the influence of high octane fuels on biofuel based dual fuel engine performance, emission, and combustion

    Directory of Open Access Journals (Sweden)

    Masimalai Senthilkumar

    2017-01-01

    Full Text Available This paper presents an experimental study on the effect of different high octane fuels (such as eucalyptus oil, ethanol, and methanol on engine’s performance behaviour of a biofuel based dual fuel engine. A single cylinder Diesel engine was modified and tested under dual fuel mode of operation. Initially the engine was run using neat diesel, neat mahua oil as fuels. In the second phase, the engine was operated in dual fuel mode by using a specially designed variable jet carburettor to supply the high octane fuels. Engine trials were made at 100% and 40% loads (power outputs with varying amounts of high octane fuels up-to the maximum possible limit. The performance and emission characteristics of the engine were obtained and analysed. Results indicated significant improvement in brake thermal efficiency simultaneous reduction in smoke and NO emissions in dual fuel operation with all the inducted fuels. At 100% load the brake thermal efficiency increased from 25.6% to a maximum of 32.3, 30.5, and 28.4%, respectively, with eucalyptus oil, ethanol, and methanol as primary fuels. Smoke was reduced drastically from 78% with neat mahua oil a minimum of 41, 48, and 53%, respectively, with eucalyptus oil, ethanol, and methanol at the maximum efficiency point. The optimal energy share for the best engine behaviour was found to be 44.6, 27.3, and 23.2%, respectively, for eucalyptus oil, ethanol, and methanol at 100% load. Among the primary fuels tested, eucalyptus oil showed the maximum brake thermal efficiency, minimum smoke and NO emissions and maximum energy replacement for the optimal operation of the engine.

  1. Understanding the role of low reactivity fuel stratification in a dual fuel RCCI engine – A simulation study

    NARCIS (Netherlands)

    Mikulski, M.; Bekdemir, C.

    2017-01-01

    Natural gas - diesel, Reactivity Controlled Compression Ignition (RCCI) is currently one of the most promising combustion strategies for the next generation heavy-duty engines. A major issue to be addressed for this dual fuel concept to become practically applicable is its low combustion efficiency

  2. Cycle to Cycle Variation Study in a Dual Fuel Operated Engine

    KAUST Repository

    Pasunurthi, Shyamsundar

    2017-03-28

    The standard capability of engine experimental studies is that ensemble averaged quantities like in-cylinder pressure from multiple cycles and emissions are reported and the cycle to cycle variation (CCV) of indicated mean effective pressure (IMEP) is captured from many consecutive combustion cycles for each test condition. However, obtaining 3D spatial distribution of all the relevant quantities such as fuel-air mixing, temperature, turbulence levels and emissions from such experiments is a challenging task. Computational Fluid Dynamics (CFD) simulations of engine flow and combustion can be used effectively to visualize such 3D spatial distributions. A dual fuel engine is considered in the current study, with manifold injected natural gas (NG) and direct injected diesel pilot for ignition. Multiple engine cycles in 3D are simulated in series like in the experiments to investigate the potential of high fidelity RANS simulations coupled with detailed chemistry, to accurately predict the CCV. Cycle to cycle variation (CCV) is expected to be due to variabilities in operating and boundary conditions, in-cylinder stratification of diesel and natural gas fuels, variation in in-cylinder turbulence levels and velocity flow-fields. In a previous publication by the authors [1], variabilities in operating and boundary conditions are incorporated into several closed cycle simulations performed in parallel. Stochastic variations/stratifications of fuel-air mixture, turbulence levels, temperature and internal combustion residuals cannot be considered in such closed cycle simulations. In this study, open cycle simulations with port injection of natural gas predicted the combined effect of the stratifications on the CCV of in-cylinder pressure. The predicted Coefficient of Variation (COV) of cylinder pressure is improved compared to the one captured by closed cycle simulations in parallel.

  3. Development of Dual Fuel Single Cylinder Natural Gas Engine an Analysis and Experimental Investigation for Performance and Emission

    Directory of Open Access Journals (Sweden)

    Syed Kaleemuddin

    2009-01-01

    Full Text Available The present study reports the experimental investigations carried and upgradation of 395 cc air cooled engine to dual fuel (CNG/Gasoline application. The original 395 cc direct injection naturally aspirated, air cooled diesel engine was first converted to run on Gasoline by addition of electronic ignition system and reduction in compression ratio to suit both gasoline and CNG application. CFX software has been employed to calculate and improve the cooling capacity of engine with the use of CNG. Materials of major engine components were reviewed to suit CNG application. The engine was subsequently tuned with dual multi-mapped ignition timing for bi-fuel stoichiometric operation on engine dynamometer and then fitted on a 3-Wheeler vehicle. The vehicle was optimized on a chassis dynamometer to meet the proposed Bharat Stage-III norms. The engine has passed current BS-II emission norms with 48% margin in CO emission and 76% margin in NMHC (Non-Methane Hydrocarbons and Extensive trials were conducted on engine and vehicle to optimize with CNG kit and minimum loaded three way cat-con to finally to met proposed BS-III norms.

  4. Experimental Investigation of Performanec of Single Cylinder 4s Diesel Engine Using Dual Vegetable Oil Blended

    Directory of Open Access Journals (Sweden)

    Prof. C. S. Koli

    2014-03-01

    Full Text Available Over the last two decades there has been a tremendous increase in the number of automobiles and a corresponding increase in the fuel price. In this regard, alternative fuels like vegetable oils play a major role. Use of pure vegetable oil in diesel engines causes some problems due to their high viscosity compared with diesel fuel. To solve the problems due to high viscosity various techniques are used. One such technique is fuel blending. This paper investigated the performance parameters of dual vegetable oil blends (mixture of Mustard oil and Palm oil with diesel on a stationary single cylinder, four stroke direct injection compression ignition engine. The blends of BB 10 (combination of Diesel 90% by volume, Mustard oil 5% by volume and Palm oil 5% by volume and blends of BB 20 (combination of Diesel 80% by volume, Mustard oil 10% by volume and Palm oil 10% by volume gave better brake thermal efficiency, lower total fuel consumption and lower brake specific fuel consumption than other blends (BB 30, BB 40 and BB 50.

  5. A numerical study on combustion process in a small compression ignition engine run dual-fuel mode (diesel-biogas)

    Science.gov (United States)

    Ambarita, H.; Widodo, T. I.; Nasution, D. M.

    2017-01-01

    In order to reduce the consumption of fossil fuel of a compression ignition (CI) engines which is usually used in transportation and heavy machineries, it can be operated in dual-fuel mode (diesel-biogas). However, the literature reviews show that the thermal efficiency is lower due to incomplete combustion process. In order to increase the efficiency, the combustion process in the combustion chamber need to be explored. Here, a commercial CFD code is used to explore the combustion process of a small CI engine run on dual fuel mode (diesel-biogas). The turbulent governing equations are solved based on finite volume method. A simulation of compression and expansions strokes at an engine speed and load of 1000 rpm and 2500W, respectively has been carried out. The pressure and temperature distributions and streamlines are plotted. The simulation results show that at engine power of 732.27 Watt the thermal efficiency is 9.05%. The experiment and simulation results show a good agreement. The method developed in this study can be used to investigate the combustion process of CI engine run on dual-fuel mode.

  6. Dual-fuel propulsion - Why it works, possible engines, and results of vehicle studies. [on earth-to-orbit Space Shuttle flights

    Science.gov (United States)

    Martin, J. A.; Wilhite, A. W.

    1979-01-01

    The reasons why dual-fuel propulsion works are discussed. Various engine options are discussed, and vehicle mass and cost results are presented for earth-to-orbit vehicles. The results indicate that dual-fuel propulsion is attractive, particularly with the dual-expander engine. A unique orbit-transfer vehicle is described which uses dual-fuel propulsion. One Space Shuttle flight and one flight of a heavy-lift Shuttle derivative are used for each orbit-transfer vehicle flight, and the payload capability is quite attractive.

  7. A comparative study of diesel ignited methane and propane dual fuel low temperature combustion in a single cylinder research engine

    Science.gov (United States)

    Raihan, Mostafa Shameem

    The objective of this thesis is to investigate and compare the performance and emissions characteristics of diesel-ignited methane and diesel-ignited propane dual fuel LTC in a single cylinder research engine (SCRE) at a constant engine load of 5.1 bar net indicated mean effective pressure (IMEP) and at a constant engine speed of 1500 RPM. Percentage of energy substitution of propane or methane (0 - 90 percent), diesel injection timing (SOI: 355 CAD -- 280 CAD), rail pressure (200 bar -- 1300 bar) and boost pressure (1.1 bar -- 1.8 bar) were varied to quantify their impact on engine performance and engine-out ISNOx, ISHC, ISCO, and smoke emissions. Advancing SOI to 310 CAD and beyond yielded simultaneous ISNOx and smoke emissions. A rail pressure of 500 bar was the optimal one for both fueling combinations while increasing boost pressure over 1.2 bar had a very little effect on ISNOx and smoke emissions.

  8. Safety Analysis of Dual Purpose Metal Cask Subjected to Impulsive Loads due to Aircraft Engine Crash

    Science.gov (United States)

    Shirai, Koji; Namba, Kosuke; Saegusa, Toshiari

    In Japan, the first Interim Storage Facility of spent nuclear fuel away from reactor site is being planned to start its commercial operation around 2010, in use of dual-purpose metal cask in the northern part of Main Japan Island. Business License Examination for safety design approval has started since March, 2007. To demonstrate the more scientific and rational performance of safety regulation activities on each phase for the first license procedure, CREPEI has executed demonstration tests with full scale casks, such as drop tests onto real targets without impact limiters(1) and seismic tests subjected to strong earthquake motions(2). Moreover, it is important to develop the knowledge for the inherent security of metal casks under extreme mechanical-impact conditions, especially for increasing interest since the terrorist attacks from 11th September 2001(3)-(6). This paper presents dynamic mechanical behavior of the metal cask lid closure system caused by direct aircraft engine crash and describes calculated results (especially, leak tightness based on relative dynamic displacements between metallic seals). Firstly, the local penetration damage of the interim storage facility building by a big passenger aircraft engine crash (diameter 2.7m, length 4.3m, weight 4.4ton, impact velocity 90m/s) has been examined. The reduced velocity is calculated by the local damage formula for concrete structure with its thickness of 70cm. The load vs. time function for this reduced velocity (60m/s) is estimated by the impact analysis using Finite Element code LS-DYNA with the full scale engine model onto a hypothetically rigid target. Secondly, as the most critical scenarios for the metal cask, two impact scenarios (horizontal impact hitting the cask and vertical impact onto the lid metallic seal system) are chosen. To consider the geometry of all bolts for two lids, the gasket reaction forces and the inner pressure of the cask cavity, the detailed three dimensional FEM models are

  9. Experimental study on the effect of varying syngas composition on the emissions of dual fuel CI engine operating at various engine speeds

    Science.gov (United States)

    Mahgoub, B. K. M.; Sulaiman, S. A.; Karim, Z. A. A.; Hagos, F. Y.

    2015-12-01

    Using syngas as a supplement fuel of diesel in dual fuel mode is a proposed solution in the effort to protect the environment and control the serious threats posed by greenhouse gas emissions from compression ignition engines. The objective of this study was to experimentally examine the effect of syngas composition on the exhaust emission of dual fuel compression ignition (CI) engine at various engine speeds, and to compare the operating ranges of imitated syngas versus pure diesel. The study was conducted using a naturally aspirated, two strokes, single cylinder 3.7 kW diesel engine operated at speeds of 1200, 2000 and 3000 rpm. The engine was tested with three different syngas compositions. Diesel fuel was partially substituted by syngas through the air inlet. The test results disclose the impact of using syngas in CI engines on emission of CO2, NOx, unburned hydrocarbons and carbon monoxide. The experimental measurements confirmed that all syngas compositions are capable of reducing the emissions of CO2 and NOX compared with diesel fuel. Wide range of diesel replacement ratios (up to 72%) was attained without any penalty. Syngas with composition of 49% N2, 12% CO2, 25% CO, 10% H2, and 4% CH4 reduced the emissions of CO2 and NOx at engine speed of 1200 rpm up to 1% and 108 ppm, respectively. The lowest emission of UHC and NOx was emitted when the engine was operating at speed of 2000 rpm and 3000 rpm, respectively with composition of 38% N2, 8% Co2, 29% CO, 19% H2, and 6% CH4. Therefore, syngas could be a promising technique for controlling NOx emissions in CI engines. However, hydrogen content in syngas is important parameter that needs to be further investigation for its effect.

  10. Study of CNG/diesel dual fuel engine's emissions by means of RBF neural network

    Institute of Scientific and Technical Information of China (English)

    刘震涛; 费少梅

    2004-01-01

    Great efforts have been made to resolve the serious environmental pollution and inevitable declining of energy resources. A review of Chinese fuel reserves and engine technology showed that compressed natural gas (CNG)/diesel dual fuel engine (DFE) was one of the best solutions for the above problems at present. In order to study and improve the emission performance of CNG/diesel DFE, an emission model for DFE based on radial basis function (RBF) neural network was developed which was a black-box input-output training data model not require priori knowledge. The RBF centers and the connected weights could be selected automatically according to the distribution of the training data in input-output space and the given approximating error. Studies showed that the predicted results accorded well with the experimental data over a large range of operating conditions from low load to high load. The developed emissions model based on the RBF neural network could be used to successfully predict and optimize the emissions performance of DFE. And the effect of the DFE main performance parameters, such as rotation speed, load, pilot quantity and injection timing, were also predicted by means of this model. In resume, an emission prediction model for CNG/diesel DFE based on RBF neural network was built for analyzing the effect of the main performance parameters on the CO, NOx emissions of DFE. The predicted results agreed quite well with the traditional emissions model, which indicated that the model had certain application value, although it still has some limitations, because of its high dependence on the quantity of the experimental sample data.

  11. Study of CNG/diesel dual fuel engine's emissions by means of RBF neural network.

    Science.gov (United States)

    Liu, Zhen-tao; Fei, Shao-mei

    2004-08-01

    Great efforts have been made to resolve the serious environmental pollution and inevitable declining of energy resources. A review of Chinese fuel reserves and engine technology showed that compressed natural gas (CNG)/diesel dual fuel engine (DFE) was one of the best solutions for the above problems at present. In order to study and improve the emission performance of CNG/diesel DFE, an emission model for DFE based on radial basis function (RBF) neural network was developed which was a black-box input-output training data model not require priori knowledge. The RBF centers and the connected weights could be selected automatically according to the distribution of the training data in input-output space and the given approximating error. Studies showed that the predicted results accorded well with the experimental data over a large range of operating conditions from low load to high load. The developed emissions model based on the RBF neural network could be used to successfully predict and optimize the emissions performance of DFE. And the effect of the DFEmain performance parameters, such as rotation speed, load, pilot quantity and injection timing, were also predicted by means of this model. In resumé, an emission prediction model for CNG/diesel DFE based on RBF neural network was built for analyzing the effect of the main performance parameters on the CO, NOx, emissions of DFE. The predicted results agreed quite well with the traditional emissions model, which indicated that the model had certain application value, although it still has some limitations, because of its high dependence on the quantity of the experimental sample data.

  12. Fabrication of scalable tissue engineering scaffolds with dual-pore microarchitecture by combining 3D printing and particle leaching

    Energy Technology Data Exchange (ETDEWEB)

    Mohanty, Soumyaranjan; Sanger, Kuldeep; Heiskanen, Arto [DTU Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs. Lyngby (Denmark); Trifol, Jon; Szabo, Peter [Danish Polymer Centre, Department of Chemical and Biochemical Engineering, Søltofts Plads, Building 229, DK-2800 Kgs. Lyngby (Denmark); Dufva, Marin; Emnéus, Jenny [DTU Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs. Lyngby (Denmark); Wolff, Anders, E-mail: anders.wolff@nanotech.dtu.dk [DTU Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs. Lyngby (Denmark)

    2016-04-01

    Limitations in controlling scaffold architecture using traditional fabrication techniques are a problem when constructing engineered tissues/organs. Recently, integration of two pore architectures to generate dual-pore scaffolds with tailored physical properties has attracted wide attention in tissue engineering community. Such scaffolds features primary structured pores which can efficiently enhance nutrient/oxygen supply to the surrounding, in combination with secondary random pores, which give high surface area for cell adhesion and proliferation. Here, we present a new technique to fabricate dual-pore scaffolds for various tissue engineering applications where 3D printing of poly(vinyl alcohol) (PVA) mould is combined with salt leaching process. In this technique the sacrificial PVA mould, determining the structured pore architecture, was filled with salt crystals to define the random pore regions of the scaffold. After crosslinking the casted polymer the combined PVA-salt mould was dissolved in water. The technique has advantages over previously reported ones, such as automated assembly of the sacrificial mould, and precise control over pore architecture/dimensions by 3D printing parameters. In this study, polydimethylsiloxane and biodegradable poly(ϵ-caprolactone) were used for fabrication. However, we show that this technique is also suitable for other biocompatible/biodegradable polymers. Various physical and mechanical properties of the dual-pore scaffolds were compared with control scaffolds with either only structured or only random pores, fabricated using previously reported methods. The fabricated dual-pore scaffolds supported high cell density, due to the random pores, in combination with uniform cell distribution throughout the scaffold, and higher cell proliferation and viability due to efficient nutrient/oxygen transport through the structured pores. In conclusion, the described fabrication technique is rapid, inexpensive, scalable, and compatible

  13. Engineering Cellular Resistance to HIV-1 Infection In Vivo Using a Dual Therapeutic Lentiviral Vector

    Directory of Open Access Journals (Sweden)

    Bryan P Burke

    2015-01-01

    Full Text Available We described earlier a dual-combination anti-HIV type 1 (HIV-1 lentiviral vector (LVsh5/C46 that downregulates CCR5 expression of transduced cells via RNAi and inhibits HIV-1 fusion via cell surface expression of cell membrane-anchored C46 antiviral peptide. This combinatorial approach has two points of inhibition for R5-tropic HIV-1 and is also active against X4-tropic HIV-1. Here, we utilize the humanized bone marrow, liver, thymus (BLT mouse model to characterize the in vivo efficacy of LVsh5/C46 (Cal-1 vector to engineer cellular resistance to HIV-1 pathogenesis. Human CD34+ hematopoietic stem/progenitor cells (HSPC either nonmodified or transduced with LVsh5/C46 vector were transplanted to generate control and treatment groups, respectively. Control and experimental groups displayed similar engraftment and multilineage hematopoietic differentiation that included robust CD4+ T-cell development. Splenocytes isolated from the treatment group were resistant to both R5- and X4-tropic HIV-1 during ex vivo challenge experiments. Treatment group animals challenged with R5-tropic HIV-1 displayed significant protection of CD4+ T-cells and reduced viral load within peripheral blood and lymphoid tissues up to 14 weeks postinfection. Gene-marking and transgene expression were confirmed stable at 26 weeks post-transplantation. These data strongly support the use of LVsh5/C46 lentiviral vector in gene and cell therapeutic applications for inhibition of HIV-1 infection.

  14. Fabrication of scalable tissue engineering scaffolds with dual-pore microarchitecture by combining 3D printing and particle leaching

    DEFF Research Database (Denmark)

    Mohanty, Soumyaranjan; Kuldeep, Kuldeep; Heiskanen, Arto

    2016-01-01

    Limitations in controlling scaffold architecture using traditional fabrication techniques are a problem when constructing engineered tissues/organs. Recently, integration of two pore architectures to generate dual-pore scaffolds with tailored physical properties has attracted wide attention...... to fabricate dual-pore scaffolds for various tissue engineering applications where 3D printing of poly(vinyl alcohol) (PVA) mould is combined with salt leaching process. In this technique the sacrificial PVA mould, determining the structured pore architecture, was filled with salt crystals to define the random...... pore regions of the scaffold. After crosslinking the casted polymer the combined PVA-salt mould was dissolved in water. The technique has advantages over previously reported ones, such as automated assembly of the sacrificial mould, and precise control over pore architecture/dimensions by 3D printing...

  15. Fabrication of scalable tissue engineering scaffolds with dual-pore microarchitecture by combining 3D printing and particle leaching.

    Science.gov (United States)

    Mohanty, Soumyaranjan; Sanger, Kuldeep; Heiskanen, Arto; Trifol, Jon; Szabo, Peter; Dufva, Marin; Emnéus, Jenny; Wolff, Anders

    2016-04-01

    Limitations in controlling scaffold architecture using traditional fabrication techniques are a problem when constructing engineered tissues/organs. Recently, integration of two pore architectures to generate dual-pore scaffolds with tailored physical properties has attracted wide attention in tissue engineering community. Such scaffolds features primary structured pores which can efficiently enhance nutrient/oxygen supply to the surrounding, in combination with secondary random pores, which give high surface area for cell adhesion and proliferation. Here, we present a new technique to fabricate dual-pore scaffolds for various tissue engineering applications where 3D printing of poly(vinyl alcohol) (PVA) mould is combined with salt leaching process. In this technique the sacrificial PVA mould, determining the structured pore architecture, was filled with salt crystals to define the random pore regions of the scaffold. After crosslinking the casted polymer the combined PVA-salt mould was dissolved in water. The technique has advantages over previously reported ones, such as automated assembly of the sacrificial mould, and precise control over pore architecture/dimensions by 3D printing parameters. In this study, polydimethylsiloxane and biodegradable poly(ϵ-caprolactone) were used for fabrication. However, we show that this technique is also suitable for other biocompatible/biodegradable polymers. Various physical and mechanical properties of the dual-pore scaffolds were compared with control scaffolds with either only structured or only random pores, fabricated using previously reported methods. The fabricated dual-pore scaffolds supported high cell density, due to the random pores, in combination with uniform cell distribution throughout the scaffold, and higher cell proliferation and viability due to efficient nutrient/oxygen transport through the structured pores. In conclusion, the described fabrication technique is rapid, inexpensive, scalable, and compatible

  16. Repacking practice for G-3 engineering driller power unit with drive shaft of dual channel reverse circulation

    Institute of Scientific and Technical Information of China (English)

    Lihong ZHU; Kun YIN; Qingyan WANG; Yong HUANG

    2008-01-01

    In order to satisfy operating requirements for constant core drilling technology in reverse circulation with hollow-through DTH,the power unit of G-3 engineering driller was ameliorated. The new one with dual channel drive shaft, achieved the perfect assemble with transmission structure of the original power unit. It could interconvert according to need by using two sets of drive shafts with direct and reverse circulation. The repacked G-3 engineering driller carried on experiment in the field test in Luanchuan molybdenum mine of Henan, whose effect was very good.

  17. PERFORMANCE, EMISSION, AND COMBUSTION CHARACTERISTICS OF A CI ENGINE USING LIQUID PETROLEUM GAS AND NEEM OIL IN DUAL FUEL MODE

    Directory of Open Access Journals (Sweden)

    Palanimuthu Vijayabalan

    2010-01-01

    Full Text Available Increased environmental awareness and depletion of resources are driving the industries to develop viable alternative fuels like vegetable oils, compresed natural gas, liquid petroleum gas, producer gas, and biogas in order to provide suitable substitute to diesel for compression ignition engine. In this investigation, a single cylinder, vertical, air-cooled diesel engine was modified to use liquid petroleum gas in dual fuel mode. The liquefied petroleum gas, was mixed with air and supplied through intake manifold. The liquid fuel neem oil or diesel was injected into the combustion chamber. The performance, emission, and combustion characteristics were studied and compared for neat fuel and dual fuel mode. The experimental results on dual fuel engine show a reduction in oxides of nitrogen up to 70% of the rated power and smoke in the entire power range. However the brake thermal efficiency was found decreased in low power range due to lower calorific value of liquid petroleum gas, and increase in higher power range due to the complete burning of liquid petroleum gas. Hydrocarbon and carbon monoxide emissions were increased significantly at lower power range and marginal variation in higher power range.

  18. Numerical and Experimental Investigation of Combustion and Knock in a Dual Fuel Gas/Diesel Compression Ignition Engine

    Directory of Open Access Journals (Sweden)

    A. Gharehghani

    2012-01-01

    Full Text Available Conventional compression ignition engines can easily be converted to a dual fuel mode of operation using natural gas as main fuel and diesel oil injection as pilot to initiate the combustion. At the same time, it is possible to increase the output power by increasing the diesel oil percentage. A detailed performance and combustion characteristic analysis of a heavy duty diesel engine has been studied in dual fuel mode of operation where natural gas is used as the main fuel and diesel oil as pilot. The influence of intake pressure and temperature on knock occurrence and the effects of initial swirl ratio on heat release rate, temperature-pressure and emission levels have been investigated in this study. It is shown that an increase in the initial swirl ratio lengthens the delay period for auto-ignition and extends the combustion period while it reduces NOx. There is an optimum value of the initial swirl ratio for a certain mixture intake temperature and pressure conditions that can achieve high thermal efficiency and low NOx emissions while decreases the tendency to knock. Simultaneous increase of intake pressure and initial swirl ratio could be the solution to power loss and knock in dual fuel engine.

  19. Econometric comparisons of liquid rocket engines for dual-fuel advanced earth-to-orbit shuttles

    Science.gov (United States)

    Martin, J. A.

    1978-01-01

    Econometric analyses of advanced Earth-to-orbit vehicles indicate that there are economic benefits from development of new vehicles beyond the space shuttle as traffic increases. Vehicle studies indicate the advantage of the dual-fuel propulsion in single-stage vehicles. This paper shows the economic effect of incorporating dual-fuel propulsion in advanced vehicles. Several dual-fuel propulsion systems are compared to a baseline hydrogen and oxygen system.

  20. Econometric comparisons of liquid rocket engines for dual-fuel advanced earth-to-orbit shuttles

    Science.gov (United States)

    Martin, J. A.

    1978-01-01

    Econometric analyses of advanced Earth-to-orbit vehicles indicate that there are economic benefits from development of new vehicles beyond the space shuttle as traffic increases. Vehicle studies indicate the advantage of the dual-fuel propulsion in single-stage vehicles. This paper shows the economic effect of incorporating dual-fuel propulsion in advanced vehicles. Several dual-fuel propulsion systems are compared to a baseline hydrogen and oxygen system.

  1. DoE Method for Operating Parameter Optimization of a Dual-Fuel BioEthanol/Diesel Light Duty Engine

    Directory of Open Access Journals (Sweden)

    Gabriele Di Blasio

    2015-01-01

    Full Text Available In recent years, alcoholic fuels have been considered as an alternative transportation biofuel even in compression ignition engines either as blended in diesel or as premixed fuel in the case of dual-fuel configuration. Within this framework, the authors investigated the possibility to improve the combustion efficiency when ethanol is used in a dual-fuel light duty diesel engine. In particular, the study was focused on reducing the HC and CO emissions at low load conditions, acting on the most influential engine calibration parameters. Since this kind of investigation would require a significant number of runs, the statistical design of experiment methodology was adopted to reduce significantly its number. As required by the DoE approach, a set of factors (injection parameters, etc. were selected. For each of them, two levels “high” and “low” were defined in a range of reasonable values. Combining the levels of all the factors, it was possible to evaluate the effects and the weight of each factor and of their combination on the outputs. The results identified the rail pressure, the pilot, and post-injection as the most influential emission parameters. Significant reductions of unburnt were found acting on those parameters without substantial penalties on the global engine performances.

  2. Improving the performance of dual fuel engines running on natural gas/LPG by using pilot fuel derived from jojoba seeds

    Energy Technology Data Exchange (ETDEWEB)

    Selim, Mohamed Y.E. [Mechanical Engineering Department, College of Engineering, UAE University, Jimmi, Al-Ain, P.O. Box 17555, Abu Dhabi (United Arab Emirates); Radwan, M.S.; Saleh, H.E. [Mechanical Power Engineering Department, Faculty of Engineering at Mattaria, Helwan University, Cairo (Egypt)

    2008-06-15

    The use of jojoba methyl ester as a pilot fuel was investigated for almost the first time as a way to improve the performance of dual fuel engine running on natural gas or liquefied petroleum gas (LPG) at part load. The dual fuel engine used was Ricardo E6 variable compression diesel engine and it used either compressed natural gas (CNG) or LPG as the main fuel and jojoba methyl ester as a pilot fuel. Diesel fuel was used as a reference fuel for the dual fuel engine results. During the experimental tests, the following have been measured: engine efficiency in terms of specific fuel consumption, brake power output, combustion noise in terms of maximum pressure rise rate and maximum pressure, exhaust emissions in terms of carbon monoxide and hydrocarbons, knocking limits in terms of maximum torque at onset of knocking, and cyclic variability data of 100 engine cycles in terms of maximum pressure and its pressure rise rate average and standard deviation. The tests examined the following engine parameters: gaseous fuel type, engine speed and load, pilot fuel injection timing, pilot fuel mass and compression ratio. Results showed that using the jojoba fuel with its improved properties has improved the dual fuel engine performance, reduced the combustion noise, extended knocking limits and reduced the cyclic variability of the combustion. (author)

  3. Dual perfluorocarbon method to noninvasively monitor dissolved oxygen concentration in tissue engineered constructs in vitro and in vivo.

    Science.gov (United States)

    Goh, Fernie; Long, Robert; Simpson, Nicholas; Sambanis, Athanassios

    2011-07-01

    Noninvasive in vivo monitoring of tissue implants provides important correlations between construct function and the observed physiologic effects. As oxygen is a key parameter affecting cell and tissue function, we established a monitoring method that utilizes (19) F nuclear magnetic resonance (NMR) spectroscopy, with perfluorocarbons (PFCs) as oxygen concentration markers, to noninvasively monitor dissolved oxygen concentration (DO) in tissue engineered implants. Specifically, we developed a dual PFC method capable of simultaneously measuring DO within a tissue construct and its surrounding environment, as the latter varies among animals and with physiologic conditions. In vitro studies using an NMR-compatible bioreactor demonstrated the feasibility of this method to monitor the DO within alginate beads containing metabolically active murine insulinoma βTC-tet cells, relative to the DO in the culture medium, under perfusion and static conditions. The DO profiles obtained under static conditions were supported by mathematical simulations of the system. In vivo, the dual PFC method was successful in tracking the oxygenation state of entrapped βTC-tet cells and the surrounding peritoneal DO over 16 days in normal mice. DO measurements correlated well with the extent of cell growth and host cell attachment examined postexplantation. The peritoneal oxygen environment was found to be variable and hypoxic, and significantly lower in the presence of metabolically active cells. The significance of the dual PFC system in providing critical DO measurements for entrapped cells and other tissue constructs, in vitro and in vivo, is discussed. Copyright © 2011 American Institute of Chemical Engineers (AIChE).

  4. Combustion and emission characteristics of a dual fuel engine operated with mahua oil and liquefied petroleum gas

    Directory of Open Access Journals (Sweden)

    Nadar Kapilan N.

    2008-01-01

    Full Text Available For the present work, a single cylinder diesel engine was modified to work in dual fuel mode. To study the feasibility of using methyl ester of mahua oil as pilot fuel, it was used as pilot fuel and liquefied petroleum gas was used as primary fuel. In dual fuel mode, pilot fuel quantity and injector opening pressure are the few variables, which affect the performance and emission of dual fuel engine. Hence, in the present work, pilot fuel quantity and injector opening pressure were varied. From the test results, it was observed that the pilot fuel quantity of 5 mg per cycle and injector opening pressure of 200 bar results in higher brake thermal efficiency. Also the exhaust emissions such as smoke, unburnt hydrocarbon and carbon monoxide are lower than other pressures and pilot fuel quantities. The higher injection pressure and proper pilot fuel quantity might have resulted in better atomization, penetration of methyl ester of mahua oil and better combustion of fuel.

  5. Fabrication of scalable tissue engineering scaffolds with dual-pore microarchitecture by combining 3D printing and particle leaching

    DEFF Research Database (Denmark)

    Mohanty, Soumyaranjan; Kuldeep, Kuldeep; Heiskanen, Arto

    2016-01-01

    to fabricate dual-pore scaffolds for various tissue engineering applications where 3D printing of poly(vinyl alcohol) (PVA) mould is combined with salt leaching process. In this technique the sacrificial PVA mould, determining the structured pore architecture, was filled with salt crystals to define the random...... pore regions of the scaffold. After crosslinking the casted polymer the combined PVA-salt mould was dissolved in water. The technique has advantages over previously reported ones, such as automated assembly of the sacrificial mould, and precise control over pore architecture/dimensions by 3D printing...

  6. Dual-frequency Eddy Current Non-destructive Detection of Fatigue Cracks in Compressor Discs of Aero Engines

    Directory of Open Access Journals (Sweden)

    B. Sasi

    2004-10-01

    Full Text Available Eddy current non-destructive testing is used to inspect the critical aircraft components. The shortcomings of the inspection method identified, based on a few accidents, necessitatethe development of high sensitive and reliable testing procedures for inspecting the critical safety related aircraft components. This paper discusses a dual-frequency eddy current testingprocedure developed for inspection of compressor discs of aero engines for detecting fatigue cracks with high sensitivity and reliability. This procedure is capable of detecting fatigue crackssmaller than 2 mm in comparison to 4 mm cracks that can be detected with the currently practiced eddy current testing procedure.

  7. Aerothermodynamic cycle analysis of a dual-spool, separate-exhaust turbofan engine with an interstage turbine burner

    Science.gov (United States)

    Liew, Ka Heng

    This study focuses on a specific engine, i.e., a dual-spool, separate-flow turbofan engine with an Interstage Turbine Burner (ITB). This conventional turbofan engine has been modified to include a secondary isobaric burner, i.e., ITB, in a transition duct between the high-pressure turbine and the low-pressure turbine. The preliminary design phase for this modified engine starts with the aerothermodynamics cycle analysis is consisting of parametric (i.e., on-design) and performance ( i.e., off-design) cycle analyses. In parametric analysis, the modified engine performance parameters are evaluated and compared with baseline engine in terms of design limitation (maximum turbine inlet temperature), flight conditions (such as flight Mach condition, ambient temperature and pressure), and design choices (such as compressor pressure ratio, fan pressure ratio, fan bypass ratio etc.). A turbine cooling model is also included to account for the effect of cooling air on engine performance. The results from the on-design analysis confirmed the advantage of using ITB, i.e., higher specific thrust with small increases in thrust specific fuel consumption, less cooling air, and less NOx production, provided that the main burner exit temperature and ITB exit temperature are properly specified. It is also important to identify the critical ITB temperature, beyond which the ITB is turned off and has no advantage at all. With the encouraging results from parametric cycle analysis, a detailed performance cycle analysis of the identical engine is also conducted for steady-state engine performance prediction. The results from off-design cycle analysis show that the ITB engine at full throttle setting has enhanced performance over baseline engine. Furthermore, ITB engine operating at partial throttle settings will exhibit higher thrust at lower specific fuel consumption and improved thermal efficiency over the baseline engine. A mission analysis is also presented to predict the fuel

  8. Main conditions and effectiveness of gas fuel use for powering of dual fuel IC self-ignition engine

    Directory of Open Access Journals (Sweden)

    Stefan POSTRZEDNIK

    2015-09-01

    Full Text Available Internal combustion engines are fuelled mostly with liquid fuels (gasoline, diesel. Nowadays the gaseous fuels are applied as driving fuel of combustion engines. In case of spark ignition engines the liquid fuel (petrol can be totally replaced by the gas fuels. This possibility in case of compression engines is essentially restricted through the higher self-ignition temperatures of the combustible gases in comparison to classical diesel oil. Solution if this problem can be achieved by using of the dual fuel system, where for ignition of the prepared fuel gas - air mixture a specified amount of the liquid fuel (diesel oil should be additionally injected into the combustion chamber. For assurance that the combustion process proceeds without mistakes and completely, some basic conditions should be satisfied. In the frame of this work, three main aspects of this problem are taken into account: a. filling efficiency of the engine, b. stoichiometry of the combustion, c. performance of mechanical parameters (torque, power. A complex analysis of these conditions has been done and some achieved important results are presented in the paper.

  9. Validation of a zero-dimensional and 2-phase combustion model for dual-fuel compression ignition engine simulation

    Directory of Open Access Journals (Sweden)

    Mikulski Maciej

    2017-01-01

    Full Text Available Increasing demands for the reduction of exhaust emissions and the pursuit to re-duce the use of fossil fuels require the search for new fuelling technologies in combustion engines. One of the most promising technologies is the multi-fuel compression ignition engine concept, in which a small dose of liquid fuel injected directly into the cylinder acts as the ignition inhibitor of the gaseous fuel. Achieving the optimum combustion process in such an engine requires the application of advanced control algorithms which require mathematical modelling support. In response to the growing demand for new simulation tools, a 0-D model of a dual-fuel engine was proposed and validated. The validation was performed in a broad range of engine operating points, including various speeds and load condition, as well as different natural gas/diesel blend ratios. It was demonstrated that the average model calculation error within the entire cycle did not exceed 6.2%, and was comparable to the measurement results cycle to cycle variations. The maximum model calculation error in a single point of a cycle was 15% for one of the complex (multipoint injection cases. In other cases, it did not exceed 11%.

  10. Transient combustion process of an IDI diesel engine with dual-throat jet at cold-starting

    Energy Technology Data Exchange (ETDEWEB)

    Li, D.; Zhu, X.; He, X.; Peng, L.

    1996-09-01

    The dual-throat jet technique has been successfully used to improve cold-starting of the swirl-type IDI diesel engines. It has been proven that, with the aid of the second throat connecting the swirl chamber and the main combustion chamber, the cold-starting process was more stable, quieter and cleaner. An intensive fundamental experimental investigation of the transient process of the ignition and combustion at cold-starting has-been conducted on a swirl-chamber IDI diesel engine with the help of high-speed photography. Based on the results of this investigation, the following conclusions have been made: (1) there exist three types of heat release rate pattern at the cold-starting, different patterns will result in different engine behavior; (2) the secondary throat has two effects on the engine starting characteristics: (a) improvement of the ignition conditions in the main chamber by directly delivering pilot fuel; (b) improvement of the fuel/air mixing process by intensifying turbulence in the swirl chamber, which depends on the geometrical shape and orientation of the throat; (3) the counter stream of air against the fuel spray accelerates dispersion and atomization of the fuel spray in the swirl chamber. It plays the primary role in assisting the cold starting of the engine.

  11. Effect of hydrogen-diesel combustion on the performance and combustion parameters of a dual fuelled diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Bose, P.K.; Banerjee, Rahul; Deb, Madhujit [Mechanical Engineering Department, National Institute of Technology, Agartala, Tripura-799055 (India)

    2013-07-01

    Petroleum crude is expected to remain main source of transport fuels at least for the next 20 to 30 years. The petroleum crude reserves however, are declining and consumption of transport fuels particularly in the developing countries is increasing at high rates. Severe shortage of liquid fuels derived from petroleum may be faced in the second half of this century. In this paper, experiments are performed in a fur stroke, single cylinder, compression ignition diesel engine with dual fuel mode. Diesel and hydrogen are used as pilot liquid and primary gaseous fuel, respectively. The objective of this study is to find out the effects on combustion and performance parameters observed at diesel hydrogen fuel mixture for all the different loadings (2kg,4kg,6kg,8kg,10kg and 12kg) in the engine.

  12. Aircraft dual-shaft jet engine with indirect action fuel flow controller

    Science.gov (United States)

    Tudosie, Alexandru-Nicolae

    2017-06-01

    The paper deals with an aircraft single-jet engine's control system, based on a fuel flow controller. Considering the engine as controlled object and its thrust the most important operation effect, from the multitude of engine's parameters only its rotational speed n is measurable and proportional to its thrust, so engine's speed has become the most important controlled parameter. Engine's control system is based on fuel injection Qi dosage, while the output is engine's speed n. Based on embedded system's main parts' mathematical models, the author has described the system by its block diagram with transfer functions; furthermore, some Simulink-Matlab simulations are performed, concerning embedded system quality (its output parameters time behavior) and, meanwhile, some conclusions concerning engine's parameters mutual influences are revealed. Quantitative determinations are based on author's previous research results and contributions, as well as on existing models (taken from technical literature). The method can be extended for any multi-spool engine, single- or twin-jet.

  13. Desempeño y emisiones de un motor de combustión interna con combustible dual Diesel – Gas natural ;Performance and emissions study of an internal combustion engine with dual fuel diesel - natural gas

    Directory of Open Access Journals (Sweden)

    Juan Miguel Mantilla González

    2015-04-01

    Full Text Available Muchos de los problemas reportados para los sistemas duales diesel- gas natural ocurren por mala dosificación del gas. Por esta razón se adaptó un sistema de alimentación dual con inyección electrónica de gas natural a un motor de combustión interna encendido por compresión. Se plantea un diseño experimental controlando el dosado de gas natural.Como resultado se obtiene un análisis comparativo entre los valoresde desempeño y emisiones desde la operación Diesel y Diesel-Gas natural. A partir de este análisis es posible observar que el desempeño del motor no se ve afectado por la operación del motor bajo el esquema Dual Diesel-GN, es decir que el motor funcionando bajo modo dual puede sostener las cargas solicitadas al motor. También se observa que la eficiencia volumétrica mejora bajo todas las condiciones de operación dual y las emisiones son mejores sólo cuando el motor trabaja a altas cargas. Many of the problems reported for dual diesel-natural gas systems occur due to poor gas dosage. For this reason a natural gas electronic injection feeding system was adapted to a compression ignitios internal combustion engine. An experimental design controlling the natural gas dosage is considered. As a result a comparative analysis between performance and emissions from the Diesel-and diesel-Natural Gas operation is obtained. From this analysis it is possible to see that engine performance is not affected by operation of the engine under the dual mode, i.e. the motor running under dual mode can support the loads applied to the engine. It is also observed that the volumetric efficiency improves under all conditions of operation and emissions from the dual mode of operation are better only when working at high engine loads.

  14. Application of dual reciprocity boundary element method to predict acoustic attenuation characteristics of marine engine exhaust silencers

    Institute of Scientific and Technical Information of China (English)

    JI Zhen-lin; WANG Xue-ren

    2008-01-01

    In marine engine exhaust silencing systems,the presence of exhaust gas flow influences the sound propagation inside the systems and the acoustic attenuation performance of silencers.In order to investigate the effects of three-dimensional gas flow and acoustic damping on the acoustic attenuation characteristics of marine engine exhaust silencers,a dual reciprocity boundary element method (DRBEM)was developed.The acoustic governing equation in three-dimensional potential flow was derived first,and then the DRBEM numerical procedure is given.Compared to the conventional boundary elementmethod (CBEM),the DRBEM considers the second order terms of flow Mach number in the acoustic governing equation,so it is suitable for the cases with higher Mach number subsonic flow.For complex exhaust silencers,it is difficult to apply the single-domain boundary element method,so a substructure approach based on the dual reciprocity boundary element method is presented.The experiments for measuring transmission loss of silencers are conducted,and the experimental setup and measurements are explained.The transmission loss of a single expansion chamber silencer with extended inlet and outlet were predicted by DRBEM and compared with the measurements.The good agreements between predictions and measurements are observed,which demonstrated that the derived acoustic governing equation and the DRBEM numerical procedure in the present study are correct.

  15. Analysis of Ignition Behavior in a Turbocharged Direct Injection Dual Fuel Engine Using Propane and Methane as Primary Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Polk, A. C.; Gibson, C. M.; Shoemaker, N. T.; Srinivasan, K. K.; Krishnan, S. R.

    2013-05-24

    This paper presents experimental analyses of the ignition delay (ID) behavior for diesel-ignited propane and diesel-ignited methane dual fuel combustion. Two sets of experiments were performed at a constant speed (1800 rev/min) using a 4-cylinder direct injection diesel engine with the stock ECU and a wastegated turbocharger. First, the effects of fuel-air equivalence ratios (© pilot ¼ 0.2-0.6 and © overall ¼ 0.2-0.9) on IDs were quantified. Second, the effects of gaseous fuel percent energy substitution (PES) and brake mean effective pressure (BMEP) (from 2.5 to 10 bar) on IDs were investigated. With constant © pilot (> 0.5), increasing © overall with propane initially decreased ID but eventually led to premature propane autoignition; however, the corresponding effects with methane were relatively minor. Cyclic variations in the start of combustion (SOC) increased with increasing © overall (at constant © pilot), more significantly for propane than for methane. With increasing PES at constant BMEP, the ID showed a nonlinear (initially increasing and later decreasing) trend at low BMEPs for propane but a linearly decreasing trend at high BMEPs. For methane, increasing PES only increased IDs at all BMEPs. At low BMEPs, increasing PES led to significantly higher cyclic SOC variations and SOC advancement for both propane and methane. Finally, the engine ignition delay (EID) was also shown to be a useful metric to understand the influence of ID on dual fuel combustion.

  16. Implementation of nanoscale circuits using dual metal gate engineered nanowire MOSFET with high-k dielectrics for low power applications

    Science.gov (United States)

    Charles Pravin, J.; Nirmal, D.; Prajoon, P.; Ajayan, J.

    2016-09-01

    This work covers the impact of dual metal gate engineered Junctionless MOSFET with various high-k dielectric in Nanoscale circuits for low power applications. Due to gate engineering in junctionless MOSFET, graded potential is obtained and results in higher electron velocity of about 31% for HfO2 than SiO2 in the channel region, which in turn improves the carrier transport efficiency. The simulation is done using sentaurus TCAD, ON current, OFF current, ION/IOFF ratio, DIBL, gain, transconductance and transconductance generation factor parameters are analysed. When using HfO2, DIBL shows a reduction of 61.5% over SiO2. The transconductance and transconductance generation factor shows an improvement of 44% and 35% respectively. The gain and output resistance also shows considerable improvement with high-k dielectrics. Using this device, inverter circuit is implemented with different high-k dielectric material and delay have been decreased by 4% with HfO2 when compared to SiO2. In addition, a significant reduction in power dissipation of the inverter circuit is obtained with high-k dielectric Dual Metal Surround Gate Junctionless Transistor than SiO2 based device. From the analysis, it is found that HfO2 will be a better alternative for the future nanoscale device.

  17. An engineering treatise on the CARE II dual mode and coverage models

    Science.gov (United States)

    1976-01-01

    A mathematical model used to calculate the reliability of any dual-mode, spare-switching computer system was described, and some illustrative examples were presented. The possibility of extending the resultant computer program further was also examined, enabling it, in particular, to accommodate computer configurations involving more than two modes of operation.

  18. Develop the dual fuel conversion system for high output, medium speed diesel engines. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-16

    The original plan for the project involved design modifications to an existing system to enhance its performance and increase the limit of power that was achieved by the original design and to apply the higher performance product to the full sized engine and test its performance. The new system would also be applied to a different engine model. The specific work would include the redesign of gas injectors, piston configurations and two types of igniters, engine instrumentation, monitoring and testing.

  19. Develop the dual fuel conversion system for high output, medium speed diesel engines. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-16

    The original plan for the project involved design modifications to an existing system to enhance its performance and increase the limit of power that was achieved by the original design and to apply the higher performance product to the full sized engine and test its performance. The new system would also be applied to a different engine model. The specific work would include the redesign of gas injectors, piston configurations and two types of igniters, engine instrumentation, monitoring and testing.

  20. Engineering

    National Research Council Canada - National Science Library

    Includes papers in the following fields: Aerospace Engineering, Agricultural Engineering, Chemical Engineering, Civil Engineering, Electrical Engineering, Environmental Engineering, Industrial Engineering, Materials Engineering, Mechanical...

  1. Engineering chromatic dispersion and effective nonlinearity in a dual-slot waveguide.

    Science.gov (United States)

    Liu, Yan; Yan, Jing; Han, Genquan

    2014-09-20

    In this paper, we propose a new dual slot based on rib-like structure, which exhibits a flat and near-zero dispersion over a 198 nm wide wavelength range. Chromatic dispersion of dual-slot silicon (Si) waveguide is mainly determined by waveguide dispersion due to the manipulating mode effective area rather than by the material dispersion. Moreover, the nonlinear coefficient and effective mode area of the waveguide are also explored in detail. A nonlinear coefficient of 1460/m/W at 1550 nm is achieved, which is 10 times larger than that of the Si rib waveguide. By changing different waveguide variables, both the dispersion and nonlinear coefficient can be tailored, thus enabling the potential for a highly nonlinear waveguide with uniform dispersion over a wide wavelength range, which could benefit the performance of broadband optical signal systems.

  2. Supercharging an internal combustion engine by aid of a dual-rotor bi-flux axial compressor

    Science.gov (United States)

    Grǎdinariu, Andrei Cristian; Mihai, Ioan

    2016-12-01

    Internal combustion engines can be supercharged in order to enhance their performances [1-3]. Engine power is proportional to the quantity of fresh fluid introduced into the cylinder. At present, the general tendency is to try to obtain actual specific powers as high as possible, for as small as possible cylinder capacity, without increasing the generated pollution hazards. The present paper investigates the impact of replacing a centrifugal turbo-compressor with an axial double-rotor bi-flux one [4]. The proposed method allows that for the same number of cylinders, an increase in discharged airflow, accompanied by a decrease in fuel consumption. Using a program developed under the MathCad environment, the present work was aimed at studying the way temperature modifies at the end of isentropic compression under supercharging conditions. Taking into account a variation between extreme limits of the ambient temperature, its influence upon the evolution of thermal load coefficient was analyzed considering the air pressure at the compressor cooling system outlet. This analysis was completed by an exergetical study of the heat evacuated through cylinder walls in supercharged engine conditions. The conducted investigation allows verification of whether significant differences can be observed between an axial, dual-rotor, bi-flux compressor and centrifugal compressors.

  3. EFFECT OF COMPRESSION RATIO ON ENERGY AND EMISSION OF VCR DIESEL ENGINE FUELLED WITH DUAL BLENDS OF BIODIESEL

    Directory of Open Access Journals (Sweden)

    R. D. EKNATH

    2014-10-01

    Full Text Available In recent 10 years biodiesel fuel was studied extensively as an alternative fuel. Most of researchers reported performance and emission of biodiesel and their blends with constant compression ratio. Also all the research was conducted with use of single biodiesel and its blend. Few reports are observed with the use of variable compression ratio and blends of more than one biodiesel. Main aim of the present study is to analyse the effect of compression ratio on the performance and emission of dual blends of biodiesel. In the present study Blends of Jatropha and Karanja with Diesel fuel was tested on single cylinder VCR DI diesel engine for compression ratio 16 and 18. High density of biodiesel fuel causes longer delay period for Jatropha fuel was observed compare with Karanja fuel. However blending of two biodiesel K20J40D results in to low mean gas temperature which is the main reason for low NOx emission.

  4. Dual-wavelength nano-engineered Thulium-doped fiber laser via bending of singlemode-multimode-singlemode fiber structure

    Science.gov (United States)

    Zulkifli, A. Z.; Latiff, A. A.; Paul, M. C.; Yasin, M.; Ahmad, H.; Harun, S. W.

    2016-12-01

    In this paper, a dual-wavelength fiber laser (DWFL) using nano-engineered Thulium-doped fiber as a gain medium with a bent singlemode-multimode-singlemode fiber structure (SMS) is demonstrated. The SMS structure is packaged systematically using Cr-39 polymer plates to provide linear bending via applied load. Experimental results have proved that the bent SMS is capable to provide highly effective wavelength filter and wavelengths stabilizer by balancing the net cavity gain between the two wavelengths. The DWFL provides very narrow spacing of 0.9 nm, narrow 3 dB spectral linewidth of ∼0.07 nm and SNR of ∼42 dB. Based on stability test, very small mode hopping is observed at the two wavelengths having deviations of ±0 nm and ±0.04 nm respectively. In conjunction, the DWFL provides very stable relative wavelength spacing with a deviation of ±0.04 nm.

  5. Moteurs composites à allumage par compression et cycle de Rankine Dual Fuel Compression Ignition Engines Operating on the Rankine Cycle

    Directory of Open Access Journals (Sweden)

    Daugas C.

    2006-11-01

    Full Text Available Sur les 60 % de l'énergie introduite dans un groupe électrogène et perdue sous forme de chaleur, une bonne partie peut être utilisée pour fabriquer à nouveau de l'électricité à partir d'une turbine à vapeur. Les moteurs dual fuel brûlant essentiellement du gaz naturel sont remarquablement placés pour une telle récupération, dont le rendement est meilleur aux charges partielles que celui des moteurs diesel classiques. Les différents types de fluides utilisés pour la récupération sont examinés : avantages des fluides organiques sur l'eau. Études d'une réalisation concrète. Fonctionnement aux charges partielles. Influence des différents paramètres pour obtenir le meilleur rapport prix/puissance. Of the 60% of input energy lost in the form of heat in a generating set, a sizeable part can be used to generate electricity again by means of a steam turbine. Dual fuel engines which mainly burn natural gas are outstandingly suitable for such a recovery process, the efficiency under partial loads being better than that of conventional diesel engines. The author considers the different types of fluids used for the recovery process superiority of organic fluids over water. Study of a concrete example. Operation with partial loads. Influence of the different parameters in the quest for the best cost-power ratio.

  6. Feasibility of a Dual-Fuel Engine Fuelled with Waste Vegetable Oil and Municipal Organic Fraction for Power Generation in Urban Areas

    Directory of Open Access Journals (Sweden)

    L. De Simio

    2012-01-01

    Full Text Available Biomass, in form of residues and waste, can be used to produce energy with low environmental impact. It is important to use the feedstock close to the places where waste are available, and with the shortest conversion pathway, to maximize the process efficiency. In particular waste vegetable oil and the organic fraction of municipal solid waste represent a good source for fuel production in urban areas. Dual fuel engines could be taken into consideration for an efficient management of these wastes. In fact, the dual fuel technology can achieve overall efficiencies typical of diesel engines with a cleaner exhaust emission. In this paper the feasibility of a cogeneration system fuelled with waste vegetable oil and biogas is discussed and the evaluation of performance and emissions is reported on the base of experimental activities on dual fuel heavy duty engine in comparison with diesel and spark ignition engines. The ratio of biogas potential from MSW and biodiesel potential from waste vegetable oil was estimated and it results suitable for dual fuel fuelling. An electric power installation of 70 kW every 10,000 people could be achieved.

  7. Numerical Model of a Variable-Combined-Cycle Engine for Dual Subsonic and Supersonic Cruise

    Directory of Open Access Journals (Sweden)

    Victor Fernandez-Villace

    2013-02-01

    Full Text Available Efficient high speed propulsion requires exploiting the cooling capability of the cryogenic fuel in the propulsion cycle. This paper presents the numerical model of a combined cycle engine while in air turbo-rocket configuration. Specific models of the various heat exchanger modules and the turbomachinery elements were developed to represent the physical behavior at off-design operation. The dynamic nature of the model allows the introduction of the engine control logic that limits the operation of certain subcomponents and extends the overall engine operational envelope. The specific impulse and uninstalled thrust are detailed while flying a determined trajectory between Mach 2.5 and 5 for varying throttling levels throughout the operational envelope.

  8. Orthogonal dual-modification of proteins for the engineering of multivalent protein scaffolds

    Directory of Open Access Journals (Sweden)

    Michaela Mühlberg

    2015-05-01

    Full Text Available To add new tools to the repertoire of protein-based multivalent scaffold design, we have developed a novel dual-labeling strategy for proteins that combines residue-specific incorporation of unnatural amino acids with chemical oxidative aldehyde formation at the N-terminus of a protein. Our approach relies on the selective introduction of two different functional moieties in a protein by mutually orthogonal copper-catalyzed azide–alkyne cycloaddition (CuAAC and oxime ligation. This method was applied to the conjugation of biotin and β-linked galactose residues to yield an enzymatically active thermophilic lipase, which revealed specific binding to Erythrina cristagalli lectin by SPR binding studies.

  9. T₁ and T₂ dual-mode MRI contrast agent for enhancing accuracy by engineered nanomaterials.

    Science.gov (United States)

    Shin, Tae-Hyun; Choi, Jin-sil; Yun, Seokhwan; Kim, Il-Sun; Song, Ho-Taek; Kim, Youngmee; Park, Kook In; Cheon, Jinwoo

    2014-04-22

    One of the holy grails in biomedical imaging technology is to achieve accurate imaging of biological targets. The development of sophisticated instrumentation and the use of contrast agents have improved the accuracy of biomedical imaging. However, the issue of false imaging remains a problem. Here, we developed a dual-mode artifact filtering nanoparticle imaging agent (AFIA) that comprises a combination of paramagnetic and superparamagnetic nanomaterials. This AFIA has the ability to perform "AND logic gate" algorithm to eliminate false errors (artifacts) from the raw images to enhance accuracy of the MRI. We confirm the artifact filtering capability of AFIA in MRI phantoms and further demonstrate that artifact-free imaging of stem cell migration is possible in vivo.

  10. A dual flow bioreactor with controlled mechanical stimulation for cartilage tissue engineering.

    Science.gov (United States)

    Spitters, Tim W G M; Leijten, Jeroen C H; Deus, Filipe D; Costa, Ines B F; van Apeldoorn, Aart A; van Blitterswijk, Clemens A; Karperien, Marcel

    2013-10-01

    In cartilage, tissue engineering bioreactors can create a controlled environment to study chondrocyte behavior under mechanical stimulation or produce chondrogenic grafts of clinically relevant size. Here we present a novel bioreactor that combines mechanical stimulation with a two compartment system through which nutrients can be supplied solely by diffusion from opposite sides of a tissue-engineered construct. This design is based on the hypothesis that creating gradients of nutrients, growth factors, and growth factor antagonists can aid in the generation of zonal tissue-engineered cartilage. Computational modeling predicted that the design facilitates the creation of a biologically relevant glucose gradient. This was confirmed by quantitative glucose measurements in cartilage explants. In this system, it is not only possible to create gradients of nutrients, but also of anabolic or catabolic factors. Therefore, the bioreactor design allows control over nutrient supply and mechanical stimulation useful for in vitro generation of cartilage constructs that can be used for the resurfacing of articulated joints or as a model for studying osteoarthritis disease progression.

  11. Efficient Dual-Site Carbon Monoxide Electro-Catalysts via Interfacial Nano-Engineering

    Science.gov (United States)

    Liu, Zhen; Huang, Zhongyuan; Cheng, Feifei; Guo, Zhanhu; Wang, Guangdi; Chen, Xu; Wang, Zhe

    2016-09-01

    Durable, highly efficient, and economic sound electrocatalysts for CO electrooxidation (COE) are the emerging key for wide variety of energy solutions, especially fuel cells and rechargeable metal‑air batteries. Herein, we report the novel system of nickel‑aluminum double layered hydroxide (NiAl-LDH) nanoplates on carbon nanotubes (CNTs) network. The formulation of such complexes system was to be induced through the assistance of gold nanoparticles in order to form dual-metal active sites so as to create a extended Au/NiO two phase zone. Bis (trifluoromethylsulfonyl)imide (NTf2) anion of ionic liquid electrolyte was selected to enhance the CO/O2 adsorption and to facilitate electro-catalyzed oxidation of Ni (OH)2 to NiOOH by increasing the electrophilicity of catalytic interface. The resulting neutral catalytic system exhibited ultra-high electrocatalytic activity and stability for CO electrooxidation than commercial and other reported precious metal catalysts. The turnover frequency (TOF) of the LDH-Au/CNTs COE catalyst was much higher than the previous reported other similar electrocatalysts, even close to the activity of solid-gas chemical catalysts at high temperature. Moreover, in the long-term durability testing, the negligible variation of current density remains exsisting after 1000 electrochemistry cycles.

  12. Concurrent System Engineering and Risk Reduction for Dual-Band (RF/optical) Spacecraft Communications

    Science.gov (United States)

    Fielhauer, Karl, B.; Boone, Bradley, G.; Raible, Daniel, E.

    2012-01-01

    This paper describes a system engineering approach to examining the potential for combining elements of a deep-space RF and optical communications payload, for the purpose of reducing the size, weight and power burden on the spacecraft and the mission. Figures of merit and analytical methodologies are discussed to conduct trade studies, and several potential technology integration strategies are presented. Finally, the NASA Integrated Radio and Optical Communications (iROC) project is described, which directly addresses the combined RF and optical approach.

  13. Rational engineering of Lactobacillus acidophilus NCFM maltose phosphorylase into either trehalose or kojibiose dual specificity phosphorylase

    DEFF Research Database (Denmark)

    Nakai, Hiroyuki; Petersen, B.O.; Westphal, Y.

    2010-01-01

    of the active site pocket as a target for specificity engineering since it contains distinct sequences for different GH65 disaccharide phosphorylases. Substitution of LaMP His413-Glu421, His413-Ile418 and His413-Glu415 from loop 3, that include His413 and Glu415 presumably recognising the alpha-anomeric O-1...... in yields superior of maltose by reverse phosphorolysis with (alpha 1, alpha 1)- and alpha-(1,2)- regioselectivity, respectively, as analysed by nuclear magnetic resonance. The loop 3 in GH65 disaccharide phosphorylase is thus a key determinant for specificity both in phosphorolysis and in regiospecific...

  14. A comprehensive study on the emission characteristics of E-diesel dual-fuel engine

    Directory of Open Access Journals (Sweden)

    A. Avinash

    2016-03-01

    Full Text Available Each year, the ultimate goal of emission legislation is to force technology to the point where a practically viable zero emission vehicle becomes a reality. Albeit the direction to reach this target is a formidable challenge, homogeneous charge compression ignition (HCCI is a new combustion concept to produce ultra low nitrogen oxides (NOx and smoke emissions. By the way, an endeavor has been made in this work to achieve a simultaneous reduction in both NOx and smoke levels in a direct injection compression ignition engine converted to operate on premixed charge compression ignition mode. Indeed, these promises were made possible in this work by preparing premixed fuel–air mixture outside the engine cylinder. For this purpose, ethanol was injected in the intake port at various premixed ratios (5%, 10%, 15%, 20%, 25% and 30% and conventional diesel was injected as usual. It was extrapolated from the experimental results that e-diesel operation can significantly reduce NOx and smoke levels. In addition, NOx and smoke levels reduced in this experimental study with increase in premixed fraction. Nevertheless, unburned hydrocarbons (UBHC and carbon monoxide (CO emissions exhibited reverse trend with increase in premixed fraction and the maximum value of HC and CO emission levels was noted with 30% premixed fraction.

  15. Dual utilization of NADPH and NADH cofactors enhances xylitol production in engineered Saccharomyces cerevisiae.

    Science.gov (United States)

    Jo, Jung-Hyun; Oh, Sun-Young; Lee, Hyeun-Soo; Park, Yong-Cheol; Seo, Jin-Ho

    2015-12-01

    Xylitol, a natural sweetener, can be produced by hydrogenation of xylose in hemicelluloses. In microbial processes, utilization of only NADPH cofactor limited commercialization of xylitol biosynthesis. To overcome this drawback, Saccharomyces cerevisiae D452-2 was engineered to express two types of xylose reductase (XR) with either NADPH-dependence or NADH-preference. Engineered S. cerevisiae DWM expressing both the XRs exhibited higher xylitol productivity than the yeast strain expressing NADPH-dependent XR only (DWW) in both batch and glucose-limited fed-batch cultures. Furthermore, the coexpression of S. cerevisiae ZWF1 and ACS1 genes in the DWM strain increased intracellular concentrations of NADPH and NADH and improved maximum xylitol productivity by 17%, relative to that for the DWM strain. Finally, the optimized fed-batch fermentation of S. cerevisiae DWM-ZWF1-ACS1 resulted in 196.2 g/L xylitol concentration, 4.27 g/L h productivity and almost the theoretical yield. Expression of the two types of XR utilizing both NADPH and NADH is a promising strategy to meet the industrial demands for microbial xylitol production.

  16. Assessment of the effect of gaseous fuel delivery mode on thermal efficiency and fuel losses during the valve overlap period in a dual-fuel compression ignition engine

    Science.gov (United States)

    Skrzek, T.

    2016-09-01

    The paper describes the effect of dual fuelling of single cylinder AVL test CI engine with the use of two ways of gas delivery to the engine manifold. The engine was fuelled diesel oil and propane. For all the tests, gas consumption was maintained at the same level. In the first mode the gas was delivered by injector located under inlet valve. In the second method, there was used a mixer fitted to the intake manifold. The paper compares the results of thermal efficiency and emissions of propane in the exhaust for both fuelling modes. Research clearly show how important it is to synchronize the injector opening time of the intake stroke. This is especially important for supercharged engines in which there is a valve overlap.

  17. Rational engineering of Lactobacillus acidophilus NCFM maltose phosphorylase into either trehalose or kojibiose dual specificity phosphorylase.

    Science.gov (United States)

    Nakai, Hiroyuki; Petersen, Bent O; Westphal, Yvonne; Dilokpimol, Adiphol; Abou Hachem, Maher; Duus, Jens Ø; Schols, Henk A; Svensson, Birte

    2010-10-01

    Lactobacillus acidophilus NCFM maltose phosphorylase (LaMP) of the (alpha/alpha)(6)-barrel glycoside hydrolase family 65 (GH65) catalyses both phosphorolysis of maltose and formation of maltose by reverse phosphorolysis with beta-glucose 1-phosphate and glucose as donor and acceptor, respectively. LaMP has about 35 and 26% amino acid sequence identity with GH65 trehalose phosphorylase (TP) and kojibiose phosphorylase (KP) from Thermoanaerobacter brockii ATCC35047. The structure of L. brevis MP and multiple sequence alignment identified (alpha/alpha)(6)-barrel loop 3 that forms the rim of the active site pocket as a target for specificity engineering since it contains distinct sequences for different GH65 disaccharide phosphorylases. Substitution of LaMP His413-Glu421, His413-Ile418 and His413-Glu415 from loop 3, that include His413 and Glu415 presumably recognising the alpha-anomeric O-1 group of the glucose moiety at subsite +1, by corresponding segments from Ser426-Ala431 in TP and Thr419-Phe427 in KP, thus conferred LaMP with phosphorolytic activity towards trehalose and kojibiose, respectively. Two different loop 3 LaMP variants catalysed the formation of trehalose and kojibiose in yields superior of maltose by reverse phosphorolysis with (alpha1, alpha1)- and alpha-(1,2)-regioselectivity, respectively, as analysed by nuclear magnetic resonance. The loop 3 in GH65 disaccharide phosphorylase is thus a key determinant for specificity both in phosphorolysis and in regiospecific reverse phosphorolysis.

  18. Magnetically engineered Cd-free quantum dots as dual-modality probes for fluorescence/magnetic resonance imaging of tumors.

    Science.gov (United States)

    Ding, Ke; Jing, Lihong; Liu, Chunyan; Hou, Yi; Gao, Mingyuan

    2014-02-01

    Magnetically engineered Cd-free CuInS2@ZnS:Mn quantum dots (QDs) were designed, synthesized, and evaluated as potential dual-modality probes for fluorescence and magnetic resonance imaging (MRI) of tumors in vivo. The synthesis of Mn-doped core-shell structured CuInS2@ZnS mainly comprised three steps, i.e., the preparation of fluorescent CuInS2 seeds, the particle surface coating of ZnS, and the Mn-doping of the ZnS shells. Systematic spectroscopy studies were carried out to illustrate the impacts of ZnS coating and the following Mn-doping on the optical properties of the QDs. In combination with conventional fluorescence, fluorescence excitation, and time-resolved fluorescence measurements, the structure of CuInS2@ZnS:Mn QDs prepared under optimized conditions presented a Zn gradient CuInS2 core and a ZnS outer shell, while Mn ions were mainly located in the ZnS shell, which well balanced the optical and magnetic properties of the resultant QDs. For the following in vivo imaging experiments, the hydrophobic CuInS2@ZnS:Mn QDs were transferred into water upon ligand exchange reactions by replacing the 1-dodecanethiol ligand with dihydrolipoic acid-poly(ethylene glycol) (DHLA-PEG) ligand. The MTT assays based on HeLa cells were carried out to evaluate the cytotoxicity of the current Cd-free CuInS2@ZnS:Mn QDs for comparing with that of water soluble CdTe QDs. Further in vivo fluorescence and MR imaging experiments suggested that the PEGylated CuInS2@ZnS:Mn QDs could well target both subcutaneous and intraperitoneal tumors in vivo.

  19. Combustion characteristics of a 4-stroke CI engine operated on Honge oil, Neem and Rice Bran oils when directly injected and dual fuelled with producer gas induction

    Energy Technology Data Exchange (ETDEWEB)

    Banapurmath, N.R.; Tewari, P.G. [Department of Mechanical Engineering, B.V.B. College of Engineering and Technology, Hubli 580031, Karnataka (India); Yaliwal, V.S. [Department of Mechanical Engineering, SDM College of Engineering and Technology, Dharwad Karnataka (India); Kambalimath, Satish [Wipro Technologies (India); Basavarajappa, Y.H. [K.L.E. Society' s Polytechnic, Hubli (India)

    2009-07-15

    Energy is an essential requirement for economic and social development of any country. Sky rocketing of petroleum fuel costs in present day has led to growing interest in alternative fuels like vegetable oils, alcoholic fuels, CNG, LPG, Producer gas, biogas in order to provide a suitable substitute to diesel for a compression ignition (CI) engine. The vegetable oils present a very promising alternative fuel to diesel oil since they are renewable, biodegradable and clean burning fuel having similar properties as that of diesel. They offer almost same power output with slightly lower thermal efficiency due to their lower energy content compared to diesel. Utilization of producer gas in CI engine on dual fuel mode provides an effective approach towards conservation of diesel fuel. Gasification involves conversion of solid biomass into combustible gases which completes combustion in a CI engines. Hence the producer gas can act as promising alternative fuel and it has high octane number (100-105) and calorific value (5-6 MJ/Nm{sup 3}). Because of its simpler structure with low carbon content results in substantial reduction of exhaust emission. Downdraft moving bed gasifier coupled with compression ignition engine are a good choice for moderate quantities of available mass up to 500 kW of electrical power. Hence bio-derived gas and vegetable liquids appear more attractive in view of their friendly environmental nature. Experiments have been conducted on a single cylinder, four-stroke, direct injection, water-cooled CI engine operated in single fuel mode using Honge, Neem and Rice Bran oils. In dual fuel mode combinations of Producer gas and three oils were used at different injection timings and injection pressures. Dual fuel mode of operation resulted in poor performance at all the loads when compared with single fuel mode at all injection timings tested. However, the brake thermal efficiency is improved marginally when the injection timing was advanced. Decreased

  20. Analyzing the Performance of a Dual Loop Organic Rankine Cycle System for Waste Heat Recovery of a Heavy-Duty Compressed Natural Gas Engine

    Directory of Open Access Journals (Sweden)

    Baofeng Yao

    2014-11-01

    Full Text Available A dual loop organic Rankine cycle (DORC system is designed to recover waste heat from a heavy-duty compressed natural gas engine (CNGE, and the performance of the DORC–CNGE combined system is simulated and discussed. The DORC system includes high-temperature (HT and low-temperature (LT cycles. The HT cycle recovers energy from the exhaust gas emitted by the engine, whereas the LT cycle recovers energy from intake air, engine coolant, and the HT cycle working fluid in the preheater. The mathematical model of the system is established based on the first and second laws of thermodynamics. The characteristics of waste heat energy from the CNGE are calculated according to engine test data under various operating conditions. Moreover, the performance of the DORC–CNGE combined system is simulated and analyzed using R245fa as the working fluid. Results show that the maximum net power output and the maximum thermal efficiency of the DORC system are 29.37 kW and 10.81%, respectively, under the rated power output condition of the engine. Compared with the original CNG engine, the maximum power output increase ratio and the maximum brake specific fuel consumption improvement ratio are 33.73% and 25%, respectively, in the DORC–CNGE combined system.

  1. Numerical Studies on Controlling Gaseous Fuel Combustion by Managing the Combustion Process of Diesel Pilot Dose in a Dual-Fuel Engine

    Directory of Open Access Journals (Sweden)

    Mikulski Maciej

    2015-06-01

    Full Text Available Protection of the environment and counteracting global warming require finding alternative sources of energy. One of the methods of generating energy from environmentally friendly sources is increasing the share of gaseous fuels in the total energy balance. The use of these fuels in compression-ignition (CI engines is difficult due to their relatively high autoignition temperature. One solution for using these fuels in CI engines is operating in a dualfuel mode, where the air and gas mixture is ignited with a liquid fuel dose. In this method, a series of relatively complex chemical processes occur in the engine's combustion chamber, related to the combustion of individual fuel fractions that interact with one another. Analysis of combustion of specific fuels in this type of fuel injection to the engine is difficult due to the fact that combustion of both fuel fractions takes place simultaneously. Simulation experiments can be used to analyse the impact of diesel fuel combustion on gaseous fuel combustion. In this paper, we discuss the results of simulation tests of combustion, based on the proprietary multiphase model of a dual-fuel engine. The results obtained from the simulation allow for analysis of the combustion process of individual fuels separately, which expands the knowledge obtained from experimental tests on the engine.

  2. 甲醇-汽油两用燃料发动机设计%Design of Petrol-methanol Dual-fuel Engine

    Institute of Scientific and Technical Information of China (English)

    杜爱民; 朱沛沛; 朱忠攀; 初川川

    2015-01-01

    A petrol-methanol dual-fuel engine was developed by locally modifying the hardware and software of a 1 .5 L inline 4-cylinder and 4-stroke engine .The dual fuel tank and rail which could be realized easily were chosen ,the fuel supply system , ignition system and control software for petrol-methanol dual-fuel were designed ,and the starting and warming up functions of petrol and the free switch and respective combustion for methanol and petrol were realized .The experiments of the dual-fuel engine show that methanol is more appropriate for transient conditions with large speed and load variance .Although the con-sumption of methanol is twice of the petrol ,the thermal efficiency of methanol is higher than that of petrol .%以一台1.5L、直列、四缸、四冲程发动机为基础开发了甲醇-汽油两用燃料发动机 ,对原发动机的硬件和软件进行了局部修改 ,选择了比较容易实现的双油箱双油轨结构 ,设计了甲醇-汽油两用的燃油供给系统、点火系统以及控制软件 ,实现了发动机汽油起动、暖机 ,甲醇、汽油之间的自由切换以及甲醇、汽油单独燃烧等功能.对甲醇-汽油两用燃料发动机进行了试验研究 ,试验表明 ,在转速变化较大而负荷相对变化较小的工况下适合燃用甲醇.虽然甲醇的消耗量大约是汽油的2倍 ,但其燃烧热效率比汽油高.

  3. 甲醇/柴油双燃料发动机燃烧过程分析%Combustion process analysis of methanol/diesel dual fuel engine

    Institute of Scientific and Technical Information of China (English)

    王忠; 李仁春; 张登攀; 李铭迪

    2013-01-01

    In recent years, environment concerns and depletion in petroleum resources have forced researchers to concentrate on exploiting renewable alternatives fuels. As a renewable and alternative fuel, methanol has gained great attendance. As for the application of methanol on compression ignition engines, researchers have focused on partial replacement of diesel with methanol, either blended with diesel or injected into the air intake. Due to the poor miscibility of diesel and methanol, an additive has to be added to form steady methanol/diesel blends. However, majority of these additives have bad influence on NOX emission. Methanol and diesel can also be applied separately to the engine. Dual injection system is one method, which is difficult and expensive to develop. Compared with other methods, intake premixed methanol is more flexible in operation and has greater potential to applied to practical application. In this paper, the methanol injection system was optimally designed according to the former investigation on air-methanol mixture formation inside internal combustion engine. However, previous research results showed that severe knock would happen at high load with high proportion of methanol. In addition, the intake charge temperature declined, owing to the high level of methanol vaporization latent heat. Thirdly, with the addition of methanol, high temperature and low temperature exothermic reaction were delayed, and the ignition delay of dual fuel was prolonged. The premixed methanol injection was controlled by intake manifold electrically system, and the combustion process of methanol/diesel dual fuel was experimentally investigated. Based on the experimental results, the optimization and application of methanol injection system were proposed, and make sure that the output power of optimized dual engine hardly changed. The experimental research was carried out on 4B26 turbocharged diesel engine. The tests were conducted at four different methanol proportion

  4. The Bacterial Flagellar Type III Export Gate Complex Is a Dual Fuel Engine That Can Use Both H+ and Na+ for Flagellar Protein Export.

    Science.gov (United States)

    Minamino, Tohru; Morimoto, Yusuke V; Hara, Noritaka; Aldridge, Phillip D; Namba, Keiichi

    2016-03-01

    The bacterial flagellar type III export apparatus utilizes ATP and proton motive force (PMF) to transport flagellar proteins to the distal end of the growing flagellar structure for self-assembly. The transmembrane export gate complex is a H+-protein antiporter, of which activity is greatly augmented by an associated cytoplasmic ATPase complex. Here, we report that the export gate complex can use sodium motive force (SMF) in addition to PMF across the cytoplasmic membrane to drive protein export. Protein export was considerably reduced in the absence of the ATPase complex and a pH gradient across the membrane, but Na+ increased it dramatically. Phenamil, a blocker of Na+ translocation, inhibited protein export. Overexpression of FlhA increased the intracellular Na+ concentration in the presence of 100 mM NaCl but not in its absence, suggesting that FlhA acts as a Na+ channel. In wild-type cells, however, neither Na+ nor phenamil affected protein export, indicating that the Na+ channel activity of FlhA is suppressed by the ATPase complex. We propose that the export gate by itself is a dual fuel engine that uses both PMF and SMF for protein export and that the ATPase complex switches this dual fuel engine into a PMF-driven export machinery to become much more robust against environmental changes in external pH and Na+ concentration.

  5. The Bacterial Flagellar Type III Export Gate Complex Is a Dual Fuel Engine That Can Use Both H+ and Na+ for Flagellar Protein Export.

    Directory of Open Access Journals (Sweden)

    Tohru Minamino

    2016-03-01

    Full Text Available The bacterial flagellar type III export apparatus utilizes ATP and proton motive force (PMF to transport flagellar proteins to the distal end of the growing flagellar structure for self-assembly. The transmembrane export gate complex is a H+-protein antiporter, of which activity is greatly augmented by an associated cytoplasmic ATPase complex. Here, we report that the export gate complex can use sodium motive force (SMF in addition to PMF across the cytoplasmic membrane to drive protein export. Protein export was considerably reduced in the absence of the ATPase complex and a pH gradient across the membrane, but Na+ increased it dramatically. Phenamil, a blocker of Na+ translocation, inhibited protein export. Overexpression of FlhA increased the intracellular Na+ concentration in the presence of 100 mM NaCl but not in its absence, suggesting that FlhA acts as a Na+ channel. In wild-type cells, however, neither Na+ nor phenamil affected protein export, indicating that the Na+ channel activity of FlhA is suppressed by the ATPase complex. We propose that the export gate by itself is a dual fuel engine that uses both PMF and SMF for protein export and that the ATPase complex switches this dual fuel engine into a PMF-driven export machinery to become much more robust against environmental changes in external pH and Na+ concentration.

  6. Hierarchical Fabrication of Engineered Vascularized Bone Biphasic Constructs via Dual 3D Bioprinting: Integrating Regional Bioactive Factors into Architectural Design.

    Science.gov (United States)

    Cui, Haitao; Zhu, Wei; Nowicki, Margaret; Zhou, Xuan; Khademhosseini, Ali; Zhang, Lijie Grace

    2016-09-01

    A biphasic artificial vascularized bone construct with regional bioactive factors is presented using dual 3D bioprinting platform technique, thereby forming a large functional bone grafts with organized vascular networks. Biocompatible mussel-inspired chemistry and "thiol-ene" click reaction are used to regionally immobilize bioactive factors during construct fabrication for modulating or improving cellular events. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Use of CRISPR/Cas9-engineered INS-1 pancreatic β cells to define the pharmacology of dual GIPR/GLP-1R agonists.

    Science.gov (United States)

    Naylor, Jacqueline; Suckow, Arthur T; Seth, Asha; Baker, David J; Sermadiras, Isabelle; Ravn, Peter; Howes, Rob; Li, Jianliang; Snaith, Mike R; Coghlan, Matthew P; Hornigold, David C

    2016-09-15

    Dual-agonist molecules combining glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) activity represent an exciting therapeutic strategy for diabetes treatment. Although challenging due to shared downstream signalling pathways, determining the relative activity of dual agonists at each receptor is essential when developing potential novel therapeutics. The challenge is exacerbated in physiologically relevant cell systems expressing both receptors. To this end, either GIP receptors (GIPR) or GLP-1 receptors (GLP-1R) were ablated via RNA-guided clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 endonucleases in the INS-1 pancreatic β-cell line. Multiple clonal cell lines harbouring gene disruptions for each receptor were isolated and assayed for receptor activity to identify functional knockouts (KOs). cAMP production in response to GIPR or GLP-1R activation was abolished and GIP- or GLP-1-induced potentiation of glucose-stimulated insulin secretion (GSIS) was attenuated in the cognate KO cell lines. The contributions of individual receptors derived from cAMP and GSIS assays were confirmed in vivo using GLP-1R KO mice in combination with a monoclonal antibody antagonist of GIPR. We have successfully applied CRISPR/Cas9-engineered cell lines to determining selectivity and relative potency contributions of dual-agonist molecules targeting receptors with overlapping native expression profiles and downstream signalling pathways. Specifically, we have characterised molecules as biased towards GIPR or GLP-1R, or with relatively balanced potency in a physiologically relevant β-cell system. This demonstrates the broad utility of CRISPR/Cas9 when applied to native expression systems for the development of drugs that target multiple receptors, particularly where the balance of receptor activity is critical.

  8. Dual-use conversion of a high-Mach-number jet engine test cell for industrial gas turbine low-emission combustor development

    Energy Technology Data Exchange (ETDEWEB)

    Pillsbury, P.W.; Ryan, W.R. [Westinghouse Electric Corp., Orlando, FL (United States); Moore, J.R. [Sverdrup Technology, Inc., Arnold AFB, TN (United States). AEDC Group

    1997-01-01

    With the recent trend of reducing US military expenditures, it has become desirable to develop dual use of certain Department of Defense facilities. These efforts have a commercial purpose, while still retaining a military benefit. The goals of these efforts are to make US business more competitive in world markets, to develop the technology to solve pressing national problems, and to maintain intact the necessary talent pool and equipment for possible military needs. In a recent initiative described in this paper, test cell equipment at the Arnold Engineering Development Center, Arnold AFB, Tennessee, was modified and expanded to allow development by the Westinghouse Electric Corporation of low-emission combustors for heavy-duty gas turbines for commercial power generation.

  9. Effect of hydrogen–diesel dual-fuel usage on performance, emissions and diesel combustion in diesel engines

    Directory of Open Access Journals (Sweden)

    Yasin Karagöz

    2016-08-01

    Full Text Available Diesel engines are inevitable parts of our daily life and will be in the future. Expensive after-treatment technologies to fulfil normative legislations about the harmful tail-pipe emissions and fuel price increase in recent years created expectations from researchers for alternative fuel applications on diesel engines. This study investigates hydrogen as additive fuel in diesel engines. Hydrogen was introduced into intake manifold using gas injectors as additive fuel in gaseous form and also diesel fuel was injected into cylinder by diesel injector and used as igniter. Energy content of introduced hydrogen was set to 0%, 25% and 50% of total fuel energy, where the 0% references neat diesel operation without hydrogen injection. Test conditions were set to full load at 750, 900, 1100, 1400, 1750 and finally 2100 r/min engine speed. Variation in engine performance, emissions and combustion characteristics with hydrogen addition was investigated. Hydrogen introduction into the engine by 25% and 50% of total charge energy reveals significant decrease in smoke emissions while dramatic increase in nitrogen oxides. With increasing hydrogen content, a slight rise is observed in total unburned hydrocarbons although CO2 and CO gaseous emissions reduced considerably. Maximum in-cylinder gas pressure and rate of heat release peak values raised with hydrogen fraction.

  10. Numerical investigation of exhaust gas emissions for a dual fuel engine configuration using diesel and pongamia oil.

    Science.gov (United States)

    Mohamed Ibrahim, N H; Udayakumar, M

    2016-12-01

    The investigation presented in this paper focuses on determination of gaseous exhaust emissions by computational simulation during combustion in compression ignition engine with pongamia oil substitution. Combustion is modeled using Equilibrium Constants Method (ECM) with MATLAB program to calculate the mole fraction of 10 combustion products when pongamia oil is burnt along with diesel at variable equivalence ratio and blend ratio. It had been observed that pongamia oil substitution causes decrease in the CO emission and increase in the NOx emission as the blend ratio as well as equivalence ratio increases. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. A dual-mode secure UHF RFID tag with a crypto engine in 0.13-μm CMOS

    Science.gov (United States)

    Tao, Yang; Linghao, Zhu; Xi, Tan; Junyu, Wang; Lirong, Zheng; Hao, Min

    2016-07-01

    An ultra-high-frequency (UHF) radio frequency identification (RFID) secure tag chip with a non-crypto mode and a crypto mode is presented. During the supply chain management, the tag works in the non-crypto mode in which the on-chip crypto engine is not enabled and the tag chip has a sensitivity of -12.8 dBm for long range communication. At the point of sales (POS), the tag will be switched to the crypto mode in order to protect the privacy of customers. In the crypto mode, an advanced encryption standard (AES) crypto engine is enabled and the sensitivity of the tag chip is switched to +2 dBm for short range communication, which is a method of physical protection. The tag chip is implemented and verified in a standard 0.13-μm CMOS process. Project supported by the National Science & Technology Pillar Program of China (No. 2015BAK36B01).

  12. Engineering a segmented dual-reservoir polyurethane intravaginal ring for simultaneous prevention of HIV transmission and unwanted pregnancy.

    Directory of Open Access Journals (Sweden)

    Justin T Clark

    Full Text Available The HIV/AIDS pandemic and its impact on women prompt the investigation of prevention strategies to interrupt sexual transmission of HIV. Long-acting drug delivery systems that simultaneously protect womenfrom sexual transmission of HIV and unwanted pregnancy could be important tools in combating the pandemic. We describe the design, in silico, in vitro and in vivo evaluation of a dual-reservoir intravaginal ring that delivers the HIV-1 reverse transcriptase inhibitor tenofovir and the contraceptive levonorgestrel for 90 days. Two polyether urethanes with two different hard segment volume fractions were used to make coaxial extruded reservoir segments with a 100 µm thick rate controlling membrane and a diameter of 5.5 mm that contain 1.3 wt% levonorgestrel. A new mechanistic diffusion model accurately described the levonorgestrel burst release in early time points and pseudo-steady state behavior at later time points. As previously described, tenofovir was formulated as a glycerol paste and filled into a hydrophilic polyurethane, hollow tube reservoir that was melt-sealed by induction welding. These tenofovir-eluting segments and 2 cm long coaxially extruded levonorgestrel eluting segments were joined by induction welding to form rings that released an average of 7.5 mg tenofovir and 21 µg levonorgestrel per day in vitro for 90 days. Levonorgestrel segments placed intravaginally in rabbits resulted in sustained, dose-dependent levels of levonorgestrel in plasma and cervical tissue for 90 days. Polyurethane caps placed between segments successfully prevented diffusion of levonorgestrel into the tenofovir-releasing segment during storage.Hydrated rings endured between 152 N and 354 N tensile load before failure during uniaxial extension testing. In summary, this system represents a significant advance in vaginal drug delivery technology, and is the first in a new class of long-acting multipurpose prevention drug delivery systems.

  13. Engineering a segmented dual-reservoir polyurethane intravaginal ring for simultaneous prevention of HIV transmission and unwanted pregnancy.

    Science.gov (United States)

    Clark, Justin T; Clark, Meredith R; Shelke, Namdev B; Johnson, Todd J; Smith, Eric M; Andreasen, Andrew K; Nebeker, Joel S; Fabian, Judit; Friend, David R; Kiser, Patrick F

    2014-01-01

    The HIV/AIDS pandemic and its impact on women prompt the investigation of prevention strategies to interrupt sexual transmission of HIV. Long-acting drug delivery systems that simultaneously protect womenfrom sexual transmission of HIV and unwanted pregnancy could be important tools in combating the pandemic. We describe the design, in silico, in vitro and in vivo evaluation of a dual-reservoir intravaginal ring that delivers the HIV-1 reverse transcriptase inhibitor tenofovir and the contraceptive levonorgestrel for 90 days. Two polyether urethanes with two different hard segment volume fractions were used to make coaxial extruded reservoir segments with a 100 µm thick rate controlling membrane and a diameter of 5.5 mm that contain 1.3 wt% levonorgestrel. A new mechanistic diffusion model accurately described the levonorgestrel burst release in early time points and pseudo-steady state behavior at later time points. As previously described, tenofovir was formulated as a glycerol paste and filled into a hydrophilic polyurethane, hollow tube reservoir that was melt-sealed by induction welding. These tenofovir-eluting segments and 2 cm long coaxially extruded levonorgestrel eluting segments were joined by induction welding to form rings that released an average of 7.5 mg tenofovir and 21 µg levonorgestrel per day in vitro for 90 days. Levonorgestrel segments placed intravaginally in rabbits resulted in sustained, dose-dependent levels of levonorgestrel in plasma and cervical tissue for 90 days. Polyurethane caps placed between segments successfully prevented diffusion of levonorgestrel into the tenofovir-releasing segment during storage.Hydrated rings endured between 152 N and 354 N tensile load before failure during uniaxial extension testing. In summary, this system represents a significant advance in vaginal drug delivery technology, and is the first in a new class of long-acting multipurpose prevention drug delivery systems.

  14. A dual-application poly (dl-lactic-co-glycolic) acid (PLGA)-chitosan composite scaffold for potential use in bone tissue engineering.

    Science.gov (United States)

    Boukari, Yamina; Qutachi, Omar; Scurr, David J; Morris, Andrew P; Doughty, Stephen W; Billa, Nashiru

    2017-11-01

    The development of patient-friendly alternatives to bone-graft procedures is the driving force for new frontiers in bone tissue engineering. Poly (dl-lactic-co-glycolic acid) (PLGA) and chitosan are well-studied and easy-to-process polymers from which scaffolds can be fabricated. In this study, a novel dual-application scaffold system was formulated from porous PLGA and protein-loaded PLGA/chitosan microspheres. Physicochemical and in vitro protein release attributes were established. The therapeutic relevance, cytocompatibility with primary human mesenchymal stem cells (hMSCs) and osteogenic properties were tested. There was a significant reduction in burst release from the composite PLGA/chitosan microspheres compared with PLGA alone. Scaffolds sintered from porous microspheres at 37 °C were significantly stronger than the PLGA control, with compressive strengths of 0.846 ± 0.272 MPa and 0.406 ± 0.265 MPa, respectively (p < 0.05). The formulation also sintered at 37 °C following injection through a needle, demonstrating its injectable potential. The scaffolds demonstrated cytocompatibility, with increased cell numbers observed over an 8-day study period. Von Kossa and immunostaining of the hMSC-scaffolds confirmed their osteogenic potential with the ability to sinter at 37 °C in situ.

  15. Experimental Investigations on the Engine Performance and Characteristics of Compression Ignition (CI Engine Using Dual Bio – Fuel Methyl Ester As Alternate Fuel With Exhaust Gas Recirculation

    Directory of Open Access Journals (Sweden)

    Inturi Vamsi,

    2015-05-01

    Full Text Available Petroleum products and resources are limited and their consumption is increasing very fast with globalization and high technology development since last decade. The emissions from the petroleum products polluting the environment considerably. Bio-fuels can be produced from diverse sources, which are subject to local geography, topology and climatology. Hence, every nation will have its own choice of a source. Duel bio-fuel represents an untapped resource of energy easily available in India. This study investigates the potential substitution of duel bio-fuel methyl ester blends for diesel as fuel for automobiles and other industrial purposes. This study is concerned with the analysis of the performance and emission characteristics of the duel bio-fuel methyl esters and comparing with petroleum diesel. The fuels used were neat methyl ester, diesel and different blends of the methyl ester with diesel. The tests were carried out on a 4.4 KW, single cylinder, direct injection, air-cooled diesel engine. The fuels used were neat duel bio-fuel methyl ester, diesel and different blends of the methyl ester with diesel. The experimental result shows that 20% of blend shows better performance with reduced pollution. This analysis shows that duel bio-fuel methyl ester and its blends are a potential substitute for diesel.

  16. Emission and operating performance of a biomethane tractor with dual fuel engine; Emissions- und Betriebsverhalten eines Biomethan-Traktors mit Zuendstrahlmotor

    Energy Technology Data Exchange (ETDEWEB)

    Mautner, Sebastian [Technologie- und Foerderzentrum (TFZ), Straubing (Germany); Emberger, Peter; Thuneke, Klaus; Remmele, Edgar

    2016-08-01

    The use of biomethane as fuel for agricultural machinery with dual fuel technology is contributing to climate protection and ensures safe fuel supply. So far, hardly any documented operational experiences are known. The aim of the project, funded by the Bavarian Ministry of Economic Affairs and Media, Energy and Technology, was to investigate practicability for daily use and the emission behaviour of a Valtra N101 prototype tractor (exhaust stage IIIA). The retrofitted dual-fuel technology of the former conventional diesel tractor simultaneously uses biomethane or natural gas and diesel as ignition fuel. During the field test over 590 working hours, the tractor showed overall high reliability. On average the operating range in dual-fuel mode with one complete filling of the gas tanks was about 11.5 hours. On the tractor test bench a significant improvement of the exhaust emissions could be observed, since the gas ECU had been optimized and changed by the manufacturer. For dual-fuel operation, nitrogen oxides (NO{sub x}) are lower, whereas carbon monoxide (CO), hydrocarbons (HC) and particulate matter emissions (PM) are higher compared to solely diesel operation. In particular, HC emissions exceed the proposed limiting value, submitted by the European Commission. This is due to incomplete gas combustion and insufficient conversion by the exhaust after-treatment-system (methane slip). A big potential for optimization is expected by adjusting the operating point-specific gasdiesel ratio and improving the exhaust gas aftertreatment system.

  17. Development of Dual Power Multirotor System

    National Research Council Canada - National Science Library

    2017-01-01

    .... This paper proposes a dual power multirotor system to combine a quadrotor using gasoline engines to provide major lift in shorter arm with another quadrotor using brushless DC motors to offer most...

  18. 基于二元线性回归的发动机比功率选择研究%Engine specific power selection research based on dual linear regression

    Institute of Scientific and Technical Information of China (English)

    张庆良

    2012-01-01

    Statistic data was collected regarding to 154 types of sedans of the five best seller automobile series in the domestic market in 2010. Their complete vehicle kerb weight, maximum speed and engine power data were gathered and relevant relations were discussed. Least square method was adopted, dual linear regression analysis was performed and engine specific power math-ematic model was constructed. Significance test and accuracy test were carried out to the model. The result showed that the derived model is effective and can provide evidence for engine specific power selection.%通过对2010年国内最畅销的五大车系共154种轿车的整备质量、最高车速及发动机功率进行统计,讨论了三者之间的关系.应用最小二乘法进行二元线性回归分析,构建了发动机比功率的数学模型.对该模型进行了显著性检验和精度检验,结果表明模型有效,可为发动机比功率的选择提供依据.

  19. Dual diagnosis

    OpenAIRE

    2013-01-01

    Dual diagnosis denotes intertwining of intellectual disabilities with mental disorders. With the help of systematic examination of literature, intellectual disabilities are determined (they are characterized by subaverage intellectual activity and difficulties in adaptive skills), along side mental disorders. Their influence is seen in changes of thinking, perception, emotionality, behaviour and cognition. Mental disorders often occur with people with intellectual disabilities (data differs f...

  20. Effects of a Dual-Loop Exhaust Gas Recirculation System and Variable Nozzle Turbine Control on the Operating Parameters of an Automotive Diesel Engine

    Directory of Open Access Journals (Sweden)

    Giorgio Zamboni

    2017-01-01

    Full Text Available Reduction of NOX emissions and fuel consumption are the main topics in engine development, forcing the adoption of complex techniques and components, whose interactions have to be clearly understood for proper and reliable operations and management of the whole system. The investigation presented in this paper aimed at the development of integrated control strategies of turbocharging, high pressure (HP and low pressure (LP exhaust gas recirculation (EGR systems for better NOX emissions and fuel consumption, while analyzing their reciprocal influence and the resulting variations of engine quantities. The study was based on an extended experimental program in three part load engine operating conditions. In the paper a comparison of the behavior of the main engine sub-systems (intake and exhaust circuits, turbocharger turbine and compressor, HP and LP EGR loops in a wide range of operating modes is presented and discussed, considering open and closed loop approaches for variable nozzle turbine (VNT control, and showing how these affect engine performance and emissions. The potential of significant decrease in NOX emissions through the integration of HP and LP EGR was confirmed, while a proper VNT management allowed for improved fuel consumption level, if an open loop control scheme is followed. At higher engine speed and load, further actions have to be applied to compensate for observed soot emissions increase.

  1. Evaluating Dual Activity LPA Receptor Pan-Antagonist/Autotaxin Inhibitors as Anti-Cancer Agents in vivo using Engineered Human Tumors

    OpenAIRE

    Xu, Xiaoyu; Yang, Guanghui; Zhang, Honglu; Glenn D Prestwich

    2009-01-01

    Using an in situ crosslinkable hydrogel that mimics the extracellular matrix (ECM), cancer cells were encapsulated and injected in vivo following a “tumor engineering” strategy for orthotopic xenografts. Specifically, we created several three-dimensional (3-D) human tumor xenografts and evaluated the tumor response to BrP-LPA, a novel dual function LPA antagonist/ATX inhibitor (LPAa/ATXi). First, we describe the model system and the optimization of semi-synthetic ECM (sECM) compositions and i...

  2. 基于双有机朗肯循环的柴油机余热回收系统性能分析%Performance Analysis of Waste Heat Recovery With a Dual Loop Organic Rankine Cycle System for Diesel Engine

    Institute of Scientific and Technical Information of China (English)

    张红光; 王宏进; 杨凯; 杨富斌; 宋松松; 常莹; 贝晨

    2015-01-01

    To take full advantage of the waste heat from a diesel engine, a set of dual loop organic Rankine cycle ( ORC ) system was designed to recover exhaust energy, waste heat from the coolant system, and released heat from turbocharged air in the intercooler of a six-cylinder diesel engine. Aspen plus software was used to model the dual loop ORC system. According to the simulation model, the operating performance of the dual loop ORC system and the fuel economy of the diesel engine wereinvestigated. The results show that the thermodynamic performance and economy performance of the diesel engine can be effectively improved by using the dual loop ORC system. Under the certain engine operating conditions, namely, engine speedis 2 000 r/min and engine torqueis 1 313 N·m, the total net power output of the dual loop ORC system is up to 43. 65 kW. The brake specific fuel consumption ( BSFC ) and the thermal efficiency of the diesel engine-dual loop ORC combined system are 191. 24 g/( kW·h) and 37. 57%, respectively. Compared with the diesel engine, the thermal efficiency of the combined system can be increased by 13. 69% and the BSFC can be reduced by 15. 86%.%为了有效回收柴油机的尾气、冷却介质和进气中冷的能量,针对一台六缸柴油机,设计了一套双有机朗肯循环系统,结合Aspen plus软件对该系统进行建模,研究双有机朗肯循环系统的运行性能,分析柴油机燃油经济性.经研究发现,加装双有机朗肯循环系统可有效改善原柴油机的热力学性能和经济性能.在设定的柴油机工况下(转速2000 r/mⅰn、转矩1313 N·m),双有机朗肯循环系统的总净输出功率最高可达43.65 kW,柴油机-双有机朗肯循环联合系统的有效燃油消耗率和热效率分别可达191.24 g/( kW·h )和37.57%,相比于原柴油机可分别改善13.69%和15.86%.

  3. QCD Dual

    DEFF Research Database (Denmark)

    Sannino, Francesco

    2009-01-01

    We uncover a novel solution of the 't Hooft anomaly matching conditions for QCD. Interestingly in the perturbative regime the new gauge theory, if interpreted as a possible QCD dual, predicts the critical number of flavors above which QCD in the nonperturbative regime, develops an infrared stable...... fixed point. Remarkably this value is identical to the maximum bound predicted in the nonpertubative regime via the all-orders conjectured beta function for nonsupersymmetric gauge theories.......We uncover a novel solution of the 't Hooft anomaly matching conditions for QCD. Interestingly in the perturbative regime the new gauge theory, if interpreted as a possible QCD dual, predicts the critical number of flavors above which QCD in the nonperturbative regime, develops an infrared stable...

  4. 废气再循环对高比例甲醇双燃料柴油机燃烧过程的影响%Influence of EGR on Combustion Process in High Methanol Proportion Dual Fuel Diesel Engine

    Institute of Scientific and Technical Information of China (English)

    李仁春; 王忠; 张登攀; 李铭迪

    2014-01-01

    在4B26增压柴油机上,以进气管电控喷射的方式掺入甲醇,实现甲醇/柴油双燃料的燃烧。采用废气再循环技术拓宽高比例甲醇双燃料柴油机的工况范围,研究EGR对燃烧过程的影响规律。结果表明:适当的EGR率可以显著降低燃烧初期时的燃烧反应速度和加速度,缸内燃烧压力振荡明显减弱。随着EGR率的增加,甲醇/柴油预混合燃烧量减少,滞燃期缩短,燃烧持续期延长,燃烧最高温度降低;原甲醇/柴油双燃料燃烧放热以预混放热为主;引入EGR后,预混放热量减少,扩散放热量增加。随着EGR率的增加,放热率峰值降低;在相同工况下,保持掺混48%甲醇不变时,甲醇/柴油双燃料发动机的指示热效率随EGR率的增加而降低。%Methanol/diesel dual fuel combustion is realized on a turbocharged diesel engine 4B26 with methanol blended in by electronically controlled intake port injection. Exhaust gas recirculation ( EGR) technology is adopted to extend the working range of dual fuel diesel engine with high proportion of methanol with its effects on combustion process studied. The results show that an appropriate EGR rate can significantly reduce the speed and acceleration of combustion reaction at initial stage and weaken the oscillation of in-cylinder combustion pressure. With the increase in EGR rate, the volume of premixed combustion of methanol/diesel blend reduces, ignition delay period shortens, combustion duration prolongs and the combustion temperature peak lowers. The main parts of heat release is premixed one for methanol/diesel dual fuel combustion in nature, but with EGR introduced, premixed heat release reduces, diffusion heat release increases, and the peak heat release rate lowers when EGR rate increa-ses. In the same working condition with a fixed methanol proportion of 48%, the indicated thermal efficiency of methanol/diesel duel fuel engine lowers with the increase of

  5. Bioprinting of a mechanically enhanced three-dimensional dual cell-laden construct for osteochondral tissue engineering using a multi-head tissue/organ building system

    Science.gov (United States)

    Shim, Jin-Hyung; Lee, Jung-Seob; Kim, Jong Young; Cho, Dong-Woo

    2012-08-01

    The aim of this study was to build a mechanically enhanced three-dimensional (3D) bioprinted construct containing two different cell types for osteochondral tissue regeneration. Recently, the production of 3D cell-laden structures using various scaffold-free cell printing technologies has opened up new possibilities. However, ideal 3D complex tissues or organs have not yet been printed because gel-state hydrogels have been used as the principal material and are unable to maintain the desired 3D structure due to their poor mechanical strength. In this study, thermoplastic biomaterial polycaprolactone (PCL), which shows relatively high mechanical properties as compared with hydrogel, was used as a framework for enhancing the mechanical stability of the bioprinted construct. Two different alginate solutions were then infused into the previously prepared framework consisting of PCL to create the 3D construct for osteochondral printing. For this work, a multi-head tissue/organ building system (MtoBS), which was particularly designed to dispense thermoplastic biomaterial and hydrogel having completely different rheology properties, was newly developed and used to bioprint osteochondral tissue. It was confirmed that the line width, position and volume control of PCL and alginate solutions were adjustable in the MtoBS. Most importantly, dual cell-laden 3D constructs consisting of osteoblasts and chondrocytes were successfully fabricated. Further, the separately dispensed osteoblasts and chondrocytes not only retained their initial position and viability, but also proliferated up to 7 days after being dispensed.

  6. Genetically engineered fusion of MAP-1 and factor H domains 1-5 generates a potent dual upstream inhibitor of both the lectin and alternative complement pathways.

    Science.gov (United States)

    Nordmaj, Mie Anemone; Munthe-Fog, Lea; Hein, Estrid; Skjoedt, Mikkel-Ole; Garred, Peter

    2015-12-01

    Inhibition of the complement cascade has emerged as an option for treatment of a range of diseases. Mannose-binding lectin/ficolin/collectin-associated protein (MAP-1) is a pattern recognition molecule (PRM)-associated inhibitor of the lectin pathway. The central regulator of the alternative pathway (AP) is complement factor H (FH). Our aim was to design a dual upstream inhibitor of both human lectin and APs by fusing MAP-1 with a part of FH. There were 2 different recombinant chimeric proteins comprising full-length human MAP-1 and the first 5 N-terminal domains of human FH designed. The FH domains were orientated either in the N- or C-terminal part of MAP-1. The complement inhibition potential in human serum was assessed. Both chimeric constructs displayed the characteristics of the native molecules and bound to the PRMs with an EC50 of ∼ 2 nM. However, when added to serum diluted 1:4 in a solid-phase functional assay, only the first 5 N-terminal domains of complement FH fused to the C-terminal part of full-length MAP-1 chimeric construct were able to combine inhibition of lectin and AP activation with an half maximal inhibitory concentration of ∼ 100 and 20 nM, respectively. No effect was seen on the classical pathway. Fusion of MAP-1 with FH domains represents a novel therapeutic approach for selective targeting upstream and central complement activation at sites of inflammation.

  7. 醇醚双燃料压燃发动机 HC排放研究%Research on HC Emission of Compression Ignition Engine Fueled with Methanol/DME Dual Fuel

    Institute of Scientific and Technical Information of China (English)

    闫妍; 张煜盛; 佘金平; 陈涌填; 谌祖迪

    2013-01-01

    以ZS195型直喷式柴油机为原型机,开展了进气道喷射醇醚混合燃料HCCI试验研究,并应用气相色谱和傅里叶红外技术对 HC排放物进行检测,详细分析了 HC排放的主要组成和变化规律。试验研究结果表明:双燃料HCCI试验的指示热效率受负荷和燃料比例影响明显,最高可达到49%,超过原柴油机10%;HC排放明显高于原柴油机,通过精密控制双燃料喷射比例和进气加温措施,能够有效降低 HC排放;二甲醚、甲醇和甲醛是 HC排放最主要的组成部分,其中甲醇在大负荷工况下排放比例会有所增大,甲醛排放受功率的影响较小,在接近爆震边界的时候会出现明显提升。%For ZS195 direct injection diesel engine ,the HCCI experiments of intake methanol/DME injection were carried out , the HC emission was measured with the gas chromatography and Fourier transform infrared technology ,and the main compo-nents and their change of HC pollutants were analyzed in detail .The results show that the indicated thermal efficiency of dual fuel is influenced by the load and mixing ratio .The highest indicated thermal efficiency is 10% higher than that of original en-gine and can reach 49% .HCCI method produces higher HC emission ,but precise control of dual fuel ratio and intake warming can reduce the HC emission effectively .DME (dimethyl ether) ,methanol and formaldehyde are the main composition of HC e-mission .The methanol proportion will increase in high load conditions and the formaldehyde emission which is slightly affected by the power will increase significantly near the knock boundary .

  8. Karakterisasi Unjuk Kerja Diesel Engine Generator Set Sistem Dual Fuel Solar-Syngas Hasil Gasifikasi Briket Municipal Solid Waste (MSW Secara Langsung

    Directory of Open Access Journals (Sweden)

    Achmad Rizkal

    2017-01-01

    Full Text Available Sejalan dengan semakin banyaknya kebutuhan energi untuk dapat digunakan sebagai bahan bakar maka perlu adanya pengembangan gas biomassa sebagai bahan bakar alternatif pada motor pembakaran dalam maka akan dilakukan penelitian mengenai aplikasi sistem dual fuel gas hasil gasifikasi biomassa municipal solid waste (msw pada sistem downdraft dengan minyak solar pada motor diesel stasioner. Penelitian ini bertujuan untuk mengetahui seberapa besar solar yang tersibtitusi dengan adanya penambahan syngas yang disalurkan secara langsung. Penelitian ini dilakukan secara eksperimental dengan proses pemasukan aliran syngas yang dihasilkan downdraft municipal solid waste (MSW kedalam saluran udara mesin diesel generator set secara langsung menggunakan sistem mixer. Pengujian dilakukan dengan putaran konstan 2000 rpm dengan pembebanan bervariasi dari 200 watt sampai dengan 2000 watt dengan interval 200 watt. Bahwa produksi syngas dari reaktor gasifikasi ditambahkan sistem bypass untuk mengetahui kesesuaian antara reaktor gasifikasi dan mesin generatorset data ṁ syngas yang dibutuhkan mesin diesel, ṁ syngas yang di bypass untuk mendapatkan kesesuaian antara produksi syngas dan yang di bypass.  Data-data yang diukur dari penelitian ini menunjukkan bahwa besar nilai mass flowrate gas syngas yang dibutuhkan mesin diesel pada AFR reaktor gasifier 1,39 sebesar 0,0003748 kg/s. Mass flowrate gas syngas yang di bypass menunjukkan nilai 0 pada saat sistem dijalankan karena seluruh gas syngas masuk kedalam ruang bakar. AFR rata-rata sebesar 14,54 ,Nilai Spesifik fuel consumption (sfc mengalami peningkatan 68% dari kondisi standar single fuel , Nilai efesiensi thermal mengalami kenaikan sebesar 7% dari kondisi single fuel, Nilai daya rata-rata sebesar 2,28kW, Nilai torsi rata-rata sebesar 10,94 N.m. Solar yang tersibtitusi sebesar 48%. Nilai temperatur (coolant, mesin, oil, dan gas buang pada setiap pembebanan mengalami kenaikan.

  9. Controlled Dual Growth Factor Delivery From Microparticles Incorporated Within Human Bone Marrow-Derived Mesenchymal Stem Cell Aggregates for Enhanced Bone Tissue Engineering via Endochondral Ossification.

    Science.gov (United States)

    Dang, Phuong N; Dwivedi, Neha; Phillips, Lauren M; Yu, Xiaohua; Herberg, Samuel; Bowerman, Caitlin; Solorio, Loran D; Murphy, William L; Alsberg, Eben

    2016-02-01

    Bone tissue engineering via endochondral ossification has been explored by chondrogenically priming cells using soluble mediators for at least 3 weeks to produce a hypertrophic cartilage template. Although recapitulation of endochondral ossification has been achieved, long-term in vitro culture is required for priming cells through repeated supplementation of inductive factors in the media. To address this challenge, a microparticle-based growth factor delivery system was engineered to drive endochondral ossification within human bone marrow-derived mesenchymal stem cell (hMSC) aggregates. Sequential exogenous presentation of soluble transforming growth factor-β1 (TGF-β1) and bone morphogenetic protein-2 (BMP-2) at various defined time courses resulted in varying degrees of chondrogenesis and osteogenesis as demonstrated by glycosaminoglycan and calcium content. The time course that best induced endochondral ossification was used to guide the development of the microparticle-based controlled delivery system for TGF-β1 and BMP-2. Gelatin microparticles capable of relatively rapid release of TGF-β1 and mineral-coated hydroxyapatite microparticles permitting more sustained release of BMP-2 were then incorporated within hMSC aggregates and cultured for 5 weeks following the predetermined time course for sequential presentation of bioactive signals. Compared with cell-only aggregates treated with exogenous growth factors, aggregates with incorporated TGF-β1- and BMP-2-loaded microparticles exhibited enhanced chondrogenesis and alkaline phosphatase activity at week 2 and a greater degree of mineralization by week 5. Staining for types I and II collagen, osteopontin, and osteocalcin revealed the presence of cartilage and bone. This microparticle-incorporated system has potential as a readily implantable therapy for healing bone defects without the need for long-term in vitro chondrogenic priming. Significance: This study demonstrates the regulation of chondrogenesis

  10. 某船柴油机推进系统控制策略优化研究%On optimization of control strategy of propulsion system for marine dual engine connected in parallel

    Institute of Scientific and Technical Information of China (English)

    范凯

    2015-01-01

    Based on the simulation and modeling of a ship’s propulsion system, this paper carries out the optimization research of the control strategy of diesel starting, normal operation control, emergency operation control, dual engine connected in parallel, and so on. The achievements are applied on the propulsion monitoring system and have been successfully veriifed through the land-based coordination-test of the propulsion system.%通过对某船推进系统进行仿真建模的基础上,开展了柴油机起动、接脱排、正常操控、应急操控、双机并车等过程控制策略的优化研究,研究成果应用于该船推进监控系统的研制,并经推进系统陆上联调试验得到成功验证。

  11. 瓦锡兰:双燃料发动机技术的行业领先者%Wartsila: Industrial leader of dual-fuel engine technology

    Institute of Scientific and Technical Information of China (English)

    马宁

    2011-01-01

    On 4th May 2010 Wartsila and Brazil Industry Group QUIP signed a contract, providing three main power modules for P-63 FPSO. Wartsila said the contract was a breakthrough as the ship was the first FPSO utilizing gas engine to generate more than 100MW power. Dalian COSCO Shipyard completed hoisting the first stage module on board the FPSO on 12th December 2011.%2010年5月4日.瓦锡兰集团与巴西工业集团QUIP签定一项合约.为P一63浮式生产储油卸油船提供三个主动力模块。瓦锡兰公司表示.该合约具有突破性意义.该船是第一艘浮式生产储油卸油船.利用燃气发动机产生超过100MWe动力.合约包括调试、动车和运行监管。

  12. The dual PI3K/mTOR inhibitor NVP-BEZ235 induces tumor regression in a genetically engineered mouse model of PIK3CA wild-type colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Jatin Roper

    Full Text Available To examine the in vitro and in vivo efficacy of the dual PI3K/mTOR inhibitor NVP-BEZ235 in treatment of PIK3CA wild-type colorectal cancer (CRC.PIK3CA mutant and wild-type human CRC cell lines were treated in vitro with NVP-BEZ235, and the resulting effects on proliferation, apoptosis, and signaling were assessed. Colonic tumors from a genetically engineered mouse (GEM model for sporadic wild-type PIK3CA CRC were treated in vivo with NVP-BEZ235. The resulting effects on macroscopic tumor growth/regression, proliferation, apoptosis, angiogenesis, and signaling were examined.In vitro treatment of CRC cell lines with NVP-BEZ235 resulted in transient PI3K blockade, sustained decreases in mTORC1/mTORC2 signaling, and a corresponding decrease in cell viability (median IC(50 = 9.0-14.3 nM. Similar effects were seen in paired isogenic CRC cell lines that differed only in the presence or absence of an activating PIK3CA mutant allele. In vivo treatment of colonic tumor-bearing mice with NVP-BEZ235 resulted in transient PI3K inhibition and sustained blockade of mTORC1/mTORC2 signaling. Longitudinal tumor surveillance by optical colonoscopy demonstrated a 97% increase in tumor size in control mice (p = 0.01 vs. a 43% decrease (p = 0.008 in treated mice. Ex vivo analysis of the NVP-BEZ235-treated tumors demonstrated a 56% decrease in proliferation (p = 0.003, no effects on apoptosis, and a 75% reduction in angiogenesis (p = 0.013.These studies provide the preclinical rationale for studies examining the efficacy of the dual PI3K/mTOR inhibitor NVP-BEZ235 in treatment of PIK3CA wild-type CRC.

  13. Dual Function of Glucosamine in Gelatin/Hyaluronic Acid Cryogel to Modulate Scaffold Mechanical Properties and to Maintain Chondrogenic Phenotype for Cartilage Tissue Engineering.

    Science.gov (United States)

    Chen, Chih-Hao; Kuo, Chang-Yi; Wang, Yan-Jie; Chen, Jyh-Ping

    2016-11-23

    Glucosamine (GlcN) fulfills many of the requirements as an ideal component in scaffolds used in cartilage tissue engineering. The incorporation of GlcN in a gelatin/hyaluronic acid (GH) cryogel scaffold could provide biological cues in maintaining the phenotype of chondrocytes. Nonetheless, substituting gelatin with GlcN may also decrease the crosslinking density and modulate the mechanical properties of the cryogel scaffold, which may be beneficial as physical cues for chondrocytes in the scaffold. Thus, we prepared cryogel scaffolds containing 9% GlcN (GH-GlcN9) and 16% GlcN (GH-GlcN16) by carbodiimide-mediated crosslinking reactions at -16 °C. The crosslinking density and the mechanical properties of the cryogel matrix could be tuned by adjusting the content of GlcN used during cryogel preparation. In general, incorporation of GlcN did not influence scaffold pore size and ultimate compressive strain but increased porosity. The GH-GlcN16 cryogel showed the highest swelling ratio and degradation rate in hyaluronidase and collagenase solutions. On the contrary, the Young's modulus, storage modulus, ultimate compressive stress, energy dissipation level, and rate of stress relaxation decreased by increasing the GlcN content in the cryogel. The release of GlcN from the scaffolds in the culture medium of chondrocytes could be sustained for 21 days for GH-GlcN16 in contrast to only 7 days for GH-GlcN9. In vitro cell culture experiments using rabbit articular chondrocytes revealed that GlcN incorporation affected cell proliferation, morphology, and maintenance of chondrogenic phenotype. Overall, GH-GlcN16 showed the best performance in maintaining chondrogenic phenotype with reduced cell proliferation rate but enhanced glycosaminoglycans (GAGs) and type II collagen (COL II) secretion. Quantitative real-time polymerase chain reaction also showed time-dependent up-regulation of cartilage-specific marker genes (COL II, aggrecan and Sox9) for GH-GlcN16. Implantation of

  14. Dual Function of Glucosamine in Gelatin/Hyaluronic Acid Cryogel to Modulate Scaffold Mechanical Properties and to Maintain Chondrogenic Phenotype for Cartilage Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Chih-Hao Chen

    2016-11-01

    Full Text Available Glucosamine (GlcN fulfills many of the requirements as an ideal component in scaffolds used in cartilage tissue engineering. The incorporation of GlcN in a gelatin/hyaluronic acid (GH cryogel scaffold could provide biological cues in maintaining the phenotype of chondrocytes. Nonetheless, substituting gelatin with GlcN may also decrease the crosslinking density and modulate the mechanical properties of the cryogel scaffold, which may be beneficial as physical cues for chondrocytes in the scaffold. Thus, we prepared cryogel scaffolds containing 9% GlcN (GH-GlcN9 and 16% GlcN (GH-GlcN16 by carbodiimide-mediated crosslinking reactions at −16 °C. The crosslinking density and the mechanical properties of the cryogel matrix could be tuned by adjusting the content of GlcN used during cryogel preparation. In general, incorporation of GlcN did not influence scaffold pore size and ultimate compressive strain but increased porosity. The GH-GlcN16 cryogel showed the highest swelling ratio and degradation rate in hyaluronidase and collagenase solutions. On the contrary, the Young’s modulus, storage modulus, ultimate compressive stress, energy dissipation level, and rate of stress relaxation decreased by increasing the GlcN content in the cryogel. The release of GlcN from the scaffolds in the culture medium of chondrocytes could be sustained for 21 days for GH-GlcN16 in contrast to only 7 days for GH-GlcN9. In vitro cell culture experiments using rabbit articular chondrocytes revealed that GlcN incorporation affected cell proliferation, morphology, and maintenance of chondrogenic phenotype. Overall, GH-GlcN16 showed the best performance in maintaining chondrogenic phenotype with reduced cell proliferation rate but enhanced glycosaminoglycans (GAGs and type II collagen (COL II secretion. Quantitative real-time polymerase chain reaction also showed time-dependent up-regulation of cartilage-specific marker genes (COL II, aggrecan and Sox9 for GH-GlcN16

  15. Holographic Heat Engines

    CERN Document Server

    Johnson, Clifford V

    2014-01-01

    It is shown that in theories of gravity where the cosmological constant is considered a thermodynamic variable, it is natural to use black holes as heat engines. Two examples are presented in detail using AdS charged black holes as the working substance. We notice that for static black holes, the maximally efficient traditional Carnot engine is also a Stirling engine. The case of negative cosmological constant supplies a natural realization of these engines in terms of the field theory description of the fluids to which they are holographically dual. We first propose a precise picture of how the traditional thermodynamic dictionary of holography is extended when the cosmological constant is dynamical and then conjecture that the engine cycles can be performed by using renormalization group flow. We speculate about the existence of a natural dual field theory counterpart to the gravitational thermodynamic volume.

  16. 75 FR 29605 - Clean Alternative Fuel Vehicle and Engine Conversions

    Science.gov (United States)

    2010-05-26

    ... Exceptions b. Heavy-Duty Engine Types and Gross Vehicle Weight Classes c. Dual-Fuel Standards 2. Useful Life... first type, dedicated alternative fueled vehicles or engines, are only capable of operating on one type of fuel. Dual-fueled vehicles or engines, the second type, can operate on two types of fuel,...

  17. Demonstration and evaluation of dual-fuel technology; Demonstration och utvaerdering av dual-fuel-tekniken

    Energy Technology Data Exchange (ETDEWEB)

    Staalhammar, Per; Erlandsson, Lennart; Willner, Kristina (AVL MTC Motortestcenter AB (Sweden)); Johannesson, Staffan (Ecoplan AB (Sweden))

    2011-06-15

    There is an increased interest for Dual Fuel (methane-Diesel) applications in Sweden since this technology is seen as one of the more interesting options for a fast and cost effective introduction of biomethane as fuel for HD engines. The Dual Fuel technology has been used for many years, mainly for stationary purpose (generators, pumps and ships) while the Spark Ignited (SI) 'Otto' technology has been used for trucks and busses. One obstacle for introducing Dual Fuel technology for busses and trucks is the EU legislation that don't allow for HD on road certification of Dual Fuel applications. Challenges with the Dual Fuel technology is to develop cost effective applications that is capable of reaching low emissions (especially CH{sub 4} and NO{sub x}) in combination with high Diesel replacement in the test cycles used for on road applications. AVL MTC Motortestcenter AB (hereinafter called AVL) has on commission by SGC (Swedish Gas technical Centre) carried out this project with the objectives to analyze the Dual Fuel (Diesel-methane) technology with focus on emissions, fuel consumption and technical challenges. One important part of this project was to carry out emission tests on selected Dual Fuel applications in Sweden and to compile experiences from existing Dual Fuel technology. This report also summarizes other commonly used technologies for methane engines and compares the Dual Fuel with conventional Diesel and Otto technologies. The major challenges with Dual Fuel applications for on road vehicles will be to develop robust and cost effective solutions that meet the emission legislations (with aged catalysts) and to increase the Diesel replacement to achieve reasonable reduction of green house gases (GHG). This is especially important when biomethane is available as fuel but not Bio-Diesel. It will probably be possible to reach EURO V emission limits with advanced Dual Fuel systems but none of the tested systems reached EURO V emission levels

  18. E85 Optimized Engine

    Energy Technology Data Exchange (ETDEWEB)

    Bower, Stanley [Ford Motor Company, Dearborn, MI (United States)

    2011-12-31

    A 5.0L V8 twin-turbocharged direct injection engine was designed, built, and tested for the purpose of assessing the fuel economy and performance in the F-Series pickup of the Dual Fuel engine concept and of an E85 optimized FFV engine. Additionally, production 3.5L gasoline turbocharged direct injection (GTDI) EcoBoost engines were converted to Dual Fuel capability and used to evaluate the cold start emissions and fuel system robustness of the Dual Fuel engine concept. Project objectives were: to develop a roadmap to demonstrate a minimized fuel economy penalty for an F-Series FFV truck with a highly boosted, high compression ratio spark ignition engine optimized to run with ethanol fuel blends up to E85; to reduce FTP 75 energy consumption by 15% - 20% compared to an equally powered vehicle with a current production gasoline engine; and to meet ULEV emissions, with a stretch target of ULEV II / Tier II Bin 4. All project objectives were met or exceeded.

  19. Methane Dual Expander Aerospike Nozzle Rocket Engine

    Science.gov (United States)

    2012-03-22

    v Acknowledgments I would like to thank my thesis advisor, Lt. Col Hartsfield, who has put great effort in discussing, teaching , and...42 NPSS Thermochemistry ................................................................................................44 Methane FPT Generation...Next is a more focused description of how NPSS uses thermochemistry and an explanation on the development of the different fluid property tables

  20. Development of a Sequencial Port Injection,Fully Electronically Controlled Gas/Diesel Dual Fuel Engine%气口顺序喷射、稀燃、全电控柴油/天然气双燃料发动机的研究

    Institute of Scientific and Technical Information of China (English)

    苏万华; 林志强; 汪洋; 谢辉; 王江; 裴毅强; 费向阳; 刘文胜; 李红珍; 王根生

    2001-01-01

    采用气口顺序喷射、稀燃、全电控柴油/天然气双燃料发动机方案,对斯太尔WD615.64增压非中冷柴油机进行了改装。试验结果表明,改装后的发动机NOx、颗粒和NMHC排放均达到了欧Ⅱ排放指标。CO和HC(含甲烷)可以通过后处理解决。%A brief review of dual fuel engine technology is given in thispaper from the point of view of technology and market in China.A sequencial port injection,lean burn,fully electronically controlled dual fuel engine was proven to be the most suitable solution to the market requirement——clean and economical.It is also a important advantage in China that the engine could operate either on CNG or on 100% diesel fuel when gas supply is interrupted.Optimization of combustion process for the purpose of low emissions and high fuel economy was carefully conducted by calibration of natural compressed gas injection quantity and timing and quantity of diesel fuel injection at all operating condtions.The effects of air/gas ratio λ on NOx,PM,THC and CO were given and analyzed.

  1. Application of dual-fuel propulsion to a single stage AMLS vehicle

    Science.gov (United States)

    Lepsch, Roger A., Jr.; Stanley, Douglas O.; Unal, Resit

    1993-01-01

    As part of NASA's Advanced Manned Launch System (AMLS) study to determine a follow-on, or complement, to the Space Shuttle, a reusable single-stage-to-orbit concept utilizing dual-fuel rocket propulsion has been examined. Several dual-fuel propulsion concepts were investigated. These include: a separate engine concept combining Russian RD-170 kerosene-fueled engines with SSME-derivative engines; the kerosene and hydrogen-fueled Russian RD-701 engine concept; and a dual-fuel, dual-expander engine concept. Analysis to determine vehicle weight and size characteristics was performed using conceptual level design techniques. A response surface methodology for multidisciplinary design was utilized to optimize the dual-fuel vehicle concepts with respect to several important propulsion system and vehicle design parameters in order to achieve minimum empty weight. Comparisons were then made with a hydrogen-fueled reference, single-stage vehicle. The tools and methods employed in the analysis process are also summarized.

  2. Minimal solution of general dual fuzzy linear systems

    Energy Technology Data Exchange (ETDEWEB)

    Abbasbandy, S. [Department of Mathematics, Science and Research Branch, Islamic Azad University, Tehran 14778 (Iran, Islamic Republic of); Department of Mathematics, Faculty of Science, Imam Khomeini International University, Qazvin 34194-288 (Iran, Islamic Republic of)], E-mail: abbasbandy@yahoo.com; Otadi, M.; Mosleh, M. [Department of Mathematics, Science and Research Branch, Islamic Azad University, Tehran 14778 (Iran, Islamic Republic of); Department of Mathematics, Islamic Azad University, Firuozkooh Branch, Firuozkooh (Iran, Islamic Republic of)

    2008-08-15

    Fuzzy linear systems of equations, play a major role in several applications in various area such as engineering, physics and economics. In this paper, we investigate the existence of a minimal solution of general dual fuzzy linear equation systems. Two necessary and sufficient conditions for the minimal solution existence are given. Also, some examples in engineering and economic are considered.

  3. Dual-Fuel Truck Fleet: Start-Up Experience

    Energy Technology Data Exchange (ETDEWEB)

    NREL

    1998-09-30

    Although dual-fuel engine technology has been in development and limited use for several years, it has only recently moved toward full-scale operational capability for heavy-duty truck applications. Unlike a bifuel engine, which has two separate fuel systems that are used one at a time, a dual-fuel engine uses two fuel systems simultaneously. One of California's South Coast Air Quality Management District (SCAQMD) current programs is a demonstration of dual-fuel engine technology in heavy-duty trucks. These trucks are being studied as part of the National Renewable Energy Laboratory's (NREL's) Alternative Fuel Truck Program. This report describes the start-up experience from the program.

  4. Optimal design for cone valve of mechanical-hydraulic dual power engine%机械-液压双元动力发动机锥形配流阀的优化

    Institute of Scientific and Technical Information of China (English)

    霍炜; 张纪鹏; 张洪信; 张铁柱

    2013-01-01

    机械-液压双元动力输出发动机(MHPE)将传统的内燃机和柱塞泵融为一体,可同时或单独输出机械、液压2种动力。MHPE采用锥形阀配流系统,其容积效率高低直接影响MHPE的整机性能。该文以容积效率为目标函数,以锥形阀的工作条件和结构尺寸为约束条件,以MHPE锥形阀的结构参数为优化变量,建立了优化模型,并基于iSIGHT软件进行优化设计。优化结果表明,优化后系统的容积效率提高5.71%,改善程度较大。%Heat energy can be converted to hydraulic energy by a traditional engine-pump system(EPS). However, the EPS has some disadvantages, such as a long transmission line, low efficiency, and a complex and heavy structure. With an integrating traditional internal combustion engine and plunger pump to remove intermediate links, a mechanical-hydraulic dual power engine (MHPE) can convert heat energy to hydraulic energy directly. Therefore, the energy conversion efficiency was improved and the structure was simplified. MHPE can output one of or both machinery and hydraulic powers, and it can be used for excavators, loaders, bulldozers, and other engineering machineries. The distribution valve, the important element of MHPE, can affect the volume efficiency of the system directly by its structure and performance. The 36114ZG4B type six-cylinders radial MHPE was developed. A-H20L type one-way cone valve with the valve disk of 0.07557 kg quality, 0.028 m large diameter, 0.021 m small diameter and 40° angle is used as an inlet valve. A DIF-L20H type one-way cone valve with the valve disk of 0.04672 kg quality, 0.021 m large diameter, 0.016 m small diameter and 45° angle was used as an outlet valve. With the volume efficiency taken as an objective function, the cone valve’s working conditions and structure dimensions taken as constraint conditions, and the cone valve’s structure parameters taken as optimization variables, an optimization model

  5. Dual Income Taxes

    DEFF Research Database (Denmark)

    Sørensen, Peter Birch

    This paper discusses the principles and practices of dual income taxation in the Nordic countries. The first part of the paper explains the rationale and the historical background for the introduction of the dual income tax and describes the current Nordic tax practices. The second part...... of the paper focuses on the problems of taxing income from small businesses and the issue of corporate-personal tax integration under the dual income tax, considering alternative ways of dealing with these challenges. In the third and final part of the paper, I briefly discuss whether introducing a dual income...... tax could be relevant for New Zealand....

  6. Dual Income Taxes

    DEFF Research Database (Denmark)

    Sørensen, Peter Birch

    This paper discusses the principles and practices of dual income taxation in the Nordic countries. The first part of the paper explains the rationale and the historical background for the introduction of the dual income tax and describes the current Nordic tax practices. The second part...... of the paper focuses on the problems of taxing income from small businesses and the issue of corporate-personal tax integration under the dual income tax, considering alternative ways of dealing with these challenges. In the third and final part of the paper, I briefly discuss whether introducing a dual income...... tax could be relevant for New Zealand....

  7. The Dual Career Family.

    Science.gov (United States)

    Gurtin, Lee

    1980-01-01

    The dual career couple is forced to make a series of choices and compromises that impact the realms of marriage and career. The dilemmas that confront dual career marriages can be overcome only by compromise, accommodation, and mutual understanding on the part of the individuals involved. A revamping of human resources and recruitment programs is…

  8. Dual Credit Report

    Science.gov (United States)

    Light, Noreen

    2016-01-01

    In 2015, legislation to improve access to dual-credit programs and to reduce disparities in access and completion--particularly for low income and underrepresented students--was enacted. The new law focused on expanding access to College in the High School but acknowledged issues in other dual-credit programs and reinforced the notion that cost…

  9. Dual Youla parameterization

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    2003-01-01

    A different aspect of using the parameterisation of all systems stabilised by a given controller, i.e. the dual Youla parameterisation, is considered. The relation between system change and the dual Youla parameter is derived in explicit form. A number of standard uncertain model descriptions are...

  10. Self-Dual Gravity

    CERN Document Server

    Krasnov, Kirill

    2016-01-01

    Self-dual gravity is a diffeomorphism invariant theory in four dimensions that describes two propagating polarisations of the graviton and has a negative mass dimension coupling constant. Nevertheless, this theory is not only renormalisable but quantum finite, as we explain. We also collect various facts about self-dual gravity that are scattered across the literature.

  11. Optical dual self functions

    Institute of Scientific and Technical Information of China (English)

    华建文; 刘立人; 王宁

    1997-01-01

    A recipe to construct the exact dual self-Fourier-Fresnel-transform functions is shown, where the Dirac comb function and transformable even periodic function are used. The mathematical proof and examples are given Then this kind of self-transform function is extended to the feasible optical dual self-transform functions.

  12. Dual doubled geometry

    NARCIS (Netherlands)

    Bergshoeff, Eric A.; Riccioni, Fabio; Alvarez-Gaumé, L.

    2011-01-01

    We probe doubled geometry with dual fundamental branes. i.e. solitons. Restricting ourselves first to solitonic branes with more than two transverse directions we find that the doubled geometry requires an effective wrapping rule for the solitonic branes which is dual to the wrapping rule for fundam

  13. Development of Dual Power Multirotor System

    Directory of Open Access Journals (Sweden)

    Chin E. Lin

    2017-01-01

    Full Text Available Vertical take-off and landing (VTOL aircraft has good flight characteristics and system performance without runway. The multirotor system has been tried to expand into larger size for longer endurance or higher payload. But the motor power to endurance ratio has been limited. Due to the specific energy of gasoline being much higher than battery, introducing gasoline engine into multirotor system can be considered. This paper proposes a dual power multirotor system to combine a quadrotor using gasoline engines to provide major lift in shorter arm with another quadrotor using brushless DC motors to offer most controllable force with longer arm. System design, fabrication, and verification of the proposed dual power multirotor system development are presented. Preliminary flights have achieved 16 kg payload for long endurance flight. This is useful for various applications with advanced improvements.

  14. Research on Dual Control

    Institute of Scientific and Technical Information of China (English)

    Duan Li; Fucai Qian; Peilin Fu

    2005-01-01

    This paper summarizes recent progress by the authors in developing two solution frameworks for dual control. The first solution framework considers a class of dual control problems where there exists a parameter uncertainty in the observation equation of the LQG problem. An analytical active dual control law is derived by a variance minimization approach. The issue of how to determine an optimal degree of active learning is then addressed, thus achieving an optimality for this class of dual control problems. The second solution framework considers a general class of discrete-time LQG problems with unknown parameters in both state and observation equations. The best possible (partial) closed-loop feedback control law is derived by exploring the future nominal posterior probabilities, thus taking into account the effect of future learning when constructing the optimal nominal dual control.

  15. Dual-Actuator Active Vibration-Control System

    Science.gov (United States)

    Kascak, Albert F.; Kiraly, Louis J.; Montague, Gerald T.; Palazzolo, Alan B.; Manchala, Daniel

    1994-01-01

    Dual-actuator active vibration-control (DAAVC) system is developmental system of type described in "Active Vibration Dampers for Rotating Machinery" (LEW-15427). System features sensors and actuators positioned and oriented at bearings to measure and counteract vibrations of shaft along either of two axes perpendicular to axis of rotation. Effective in damping vibrations of helicopter-engine test stand, making it safer to operate engine at speeds near and above first resonance of engine/test-stand system. Opens new opportunities for engine designers to draw more power from engine, and concept applicable to other rotating machines.

  16. Design, development and implantation in experimental fleet of dual fuel motor systems, by alcohol carbonation, in Diesel engines; Projeto, desenvolvimento e implantacao em frotas experimentais de sistema de dupla alimentacao, por carburacao de alcool, em motores de ciclo diesel

    Energy Technology Data Exchange (ETDEWEB)

    Martelli, P. [Servicos Tecnicos e Comercio Internacional Ltda. (SETEX) (Brazil)

    1984-12-31

    This paper presents a consolidated process through testing results, showing a simple, economical and reversible conception, aiming a partial substitution of diesel fuel by hydrated ethanol, in the brazilian fleet, by means of installing a kit named Dual Fuel Motor Kit. (author). 5 figs

  17. Dual-Fuel Propulsion in Single-Stage Advanced Manned Launch System Vehicle

    Science.gov (United States)

    Lepsch, Roger A., Jr.; Stanley, Douglas O.; Unal, Resit

    1995-01-01

    As part of the United States Advanced Manned Launch System study to determine a follow-on, or complement, to the Space Shuttle, a reusable single-stage-to-orbit concept utilizing dual-fuel rocket propulsion has been examined. Several dual-fuel propulsion concepts were investigated. These include: a separate-engine concept combining Russian RD-170 kerosene-fueled engines with space shuttle main engine-derivative engines: the kerosene- and hydrogen-fueled Russian RD-701 engine; and a dual-fuel, dual-expander engine. Analysis to determine vehicle weight and size characteristics was performed using conceptual-level design techniques. A response-surface methodology for multidisciplinary design was utilized to optimize the dual-fuel vehicles with respect to several important propulsion-system and vehicle design parameters, in order to achieve minimum empty weight. The tools and methods employed in the analysis process are also summarized. In comparison with a reference hydrogen- fueled single-stage vehicle, results showed that the dual-fuel vehicles were from 10 to 30% lower in empty weight for the same payload capability, with the dual-expander engine types showing the greatest potential.

  18. Dual Credit/Dual Enrollment and Data Driven Policy Implementation

    Science.gov (United States)

    Lichtenberger, Eric; Witt, M. Allison; Blankenberger, Bob; Franklin, Doug

    2014-01-01

    The use of dual credit has been expanding rapidly. Dual credit is a college course taken by a high school student for which both college and high school credit is given. Previous studies provided limited quantitative evidence that dual credit/dual enrollment is directly connected to positive student outcomes. In this study, predictive statistics…

  19. Dual coil ignition system

    Energy Technology Data Exchange (ETDEWEB)

    Huberts, Garlan J.; Qu, Qiuping; Czekala, Michael Damian

    2017-03-28

    A dual coil ignition system is provided. The dual coil ignition system includes a first inductive ignition coil including a first primary winding and a first secondary winding, and a second inductive ignition coil including a second primary winding and a second secondary winding, the second secondary winding connected in series to the first secondary winding. The dual coil ignition system further includes a diode network including a first diode and a second diode connected between the first secondary winding and the second secondary winding.

  20. Dual energy CT

    DEFF Research Database (Denmark)

    Al-Najami, Issam; Drue, Henrik Christian; Steele, Robert

    2017-01-01

    and inaccurate with existing methods. Dual Energy Computed Tomography (DECT) enables qualitative tissue differentiation by simultaneous scanning with different levels of energy. We aimed to assess the feasibility of DECT in quantifying tumor response to neoadjuvant therapy in loco-advanced rectal cancer. METHODS...... to determine the average quantitative parameters; effective-Z, water- and iodine-concentration, Dual Energy Index (DEI), and Dual Energy Ratio (DER). These parameters were compared to the regression in the resection specimen as measured by the pathologist. RESULTS: Changes in the quantitative parameters...

  1. 40 CFR 1045.230 - How do I select engine families?

    Science.gov (United States)

    2010-07-01

    ... family, as long as they are identical to the engine configuration with respect to that fuel type for the... of the engine in the same engine family as the dual-fuel engine if engine operation on each fuel type... 40 Protection of Environment 32 2010-07-01 2010-07-01 false How do I select engine families?...

  2. Walkable dual emissions

    National Research Council Canada - National Science Library

    Xu, Hai-Bing; Jiao, Peng-Chong; Kang, Bin; Deng, Jian-Guo; Zhang, Yan

    2013-01-01

    Walkable dual emissions, in which the emission bands of the walker reversibly cross or leave those of the stationary ones depending on temperature and concentration, have been demonstrated in cyclic...

  3. Control of gear shifts in dual clutch transmission powertrains

    Science.gov (United States)

    Walker, Paul D.; Zhang, Nong; Tamba, Richard

    2011-08-01

    To achieve the best possible responses during shifting in dual clutch transmissions it is commonplace to integrate clutch and engine control, while the clutch is used to match speeds between the engine and wheels via reduction gears, poor engine control can lead to extended engagement times and rough/harsh shift transients. This paper proposes a method for combined speed and torque control of vehicle powertrains with dual clutch transmissions for both the engine and clutches. The vehicle powertrain is modelled as a simple four degree of freedom system with reduction gears and two clutches. Including a detailed clutch hydraulic model, comprising of the direct acting solenoids and clutch piston with the hydraulic fluid modelled as a compressible fluid. Powertrain control is realised through control of clutch solenoids and manipulation of the engine throttle input. Sensitivity study of clutch performance evaluating inaccurate torque estimation demonstrated variance in the response of the hydraulic system, with an indicative simulation of poor estimation resulting in increased powertrain vibration during and after shifting. Simulations are conducted to demonstrate the capacity for this method of engine and clutch control to further reduce shift transients developed in dual clutch transmission powertrains. The obtained results also show that the adoption of torque based control techniques for both the clutch and engine, which makes use of the estimated target clutch torque, significantly improves the powertrain response as a result of reduction in the lockup discontinuities.

  4. Internal combustion piston engines

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C.L.

    1977-07-01

    Current worldwide production of internal combustion piston engines includes many diversified types of designs and a very broad range of sizes. Engine sizes range from a few horsepower in small mobile units to over 40,000 brake horsepower in large stationary and marine units. The key characteristics of internal combustion piston engines considered appropriate for use as prime movers in Integrated Community Energy Systems (ICES) are evaluated. The categories of engines considered include spark-ignition gas engines, compression-ignition oil (diesel) engines, and dual-fuel engines. The engines are evaluated with respect to full-load and part-load performance characteristics, reliability, environmental concerns, estimated 1976 cost data, and current and future status of development. The largest internal combustion piston engines manufactured in the United States range up to 13,540 rated brake horsepower. Future development efforts are anticipated to result in a 20 to 25% increase in brake horsepower without increase in or loss of weight, economy, reliability, or life expectancy, predicated on a simple extension of current development trends.

  5. Engineering Encounters: Engineering Adaptations

    Science.gov (United States)

    Gatling, Anne; Vaughn, Meredith Houle

    2015-01-01

    Engineering is not a subject that has historically been taught in elementary schools, but with the emphasis on engineering in the "Next Generation Science Standards," curricula are being developed to explicitly teach engineering content and design. However, many of the scientific investigations already conducted with students have…

  6. Engineering Encounters: Engineering Adaptations

    Science.gov (United States)

    Gatling, Anne; Vaughn, Meredith Houle

    2015-01-01

    Engineering is not a subject that has historically been taught in elementary schools, but with the emphasis on engineering in the "Next Generation Science Standards," curricula are being developed to explicitly teach engineering content and design. However, many of the scientific investigations already conducted with students have…

  7. Dual phase evolution

    CERN Document Server

    Green, David G; Abbass, Hussein A

    2014-01-01

    This book explains how dual phase evolution operates in all these settings and provides a detailed treatment of the subject. The authors discuss the theoretical foundations for the theory, how it relates to other phase transition phenomena and its advantages in evolutionary computation and complex adaptive systems. The book provides methods and techniques to use this concept for problem solving. Dual phase evolution concerns systems that evolve via repeated phase shifts in the connectivity of their elements. It occurs in vast range of settings, including natural systems (species evolution, landscape ecology, geomorphology), socio-economic systems (social networks) and in artificial systems (annealing, evolutionary computing).

  8. Dual-Coding Theory and Connectionist Lexical Selection

    CERN Document Server

    Wang, Y Y

    1994-01-01

    We introduce the bilingual dual-coding theory as a model for bilingual mental representation. Based on this model, lexical selection neural networks are implemented for a connectionist transfer project in machine translation. This lexical selection approach has two advantages. First, it is learnable. Little human effort on knowledge engineering is required. Secondly, it is psycholinguistically well-founded.

  9. Commuting Dual Toeplitz Operators on the Polydisk

    Institute of Scientific and Technical Information of China (English)

    Yu Feng LU; Shu Xia SHANG

    2007-01-01

    On the polydisk, the commutativity of dual Toeplitz operators is studied. We obtain characterizations of commuting dual Toeplitz operators, essentially commuting dual Toeplitz operators and essentially semi-commuting dual Toeplitz operators.

  10. Early Dual Language Learning

    Science.gov (United States)

    Genesee, Fred

    2008-01-01

    Parents and child care personnel in English-dominant parts of the world often express misgivings about raising children bilingually. Their concerns are based on the belief that dual language learning during the infant-toddler stage confuses children, delays their development, and perhaps even results in reduced language competence. In this…

  11. 77 FR 66936 - Special Conditions: Turbomeca Ardiden 3K Turboshaft Engine

    Science.gov (United States)

    2012-11-08

    ... system includes a dual-channel full-authority digital-electronic control. The engine will incorporate a... turboshaft designed for a transport category twin-engine helicopter. The helicopter manufacturer...

  12. Dual-readout Calorimetry

    CERN Document Server

    Akchurin, N; Cardini, A.; Cascella, M.; Cei, F.; De Pedis, D.; Fracchia, S.; Franchino, S.; Fraternali, M.; Gaudio, G.; Genova, P.; Hauptman, J.; La Rotonda, L.; Lee, S.; Livan, M.; Meoni, E.; Moggi, A.; Pinci, D.; Policicchio, A.; Saraiva, J.G.; Sill, A.; Venturelli, T.; Wigmans, R.

    2013-01-01

    The RD52 Project at CERN is a pure instrumentation experiment whose goal is to un- derstand the fundamental limitations to hadronic energy resolution, and other aspects of energy measurement, in high energy calorimeters. We have found that dual-readout calorimetry provides heretofore unprecedented information event-by-event for energy resolution, linearity of response, ease and robustness of calibration, fidelity of data, and particle identification, including energy lost to binding energy in nuclear break-up. We believe that hadronic energy resolutions of {\\sigma}/E $\\approx$ 1 - 2% are within reach for dual-readout calorimeters, enabling for the first time comparable measurement preci- sions on electrons, photons, muons, and quarks (jets). We briefly describe our current progress and near-term future plans. Complete information on all aspects of our work is available at the RD52 website http://highenergy.phys.ttu.edu/dream/.

  13. Higher Representations Duals

    DEFF Research Database (Denmark)

    Sannino, Francesco

    2010-01-01

    We uncover novel solutions of the 't Hooft anomaly matching conditions for scalarless gauge theories with matter transforming according to higher dimensional representations of the underlying gauge group. We argue that, if the duals exist, they are gauge theories with fermions transforming...... according to the defining representation of the dual gauge group. The resulting conformal windows match the one stemming from the all-orders beta function results when taking the anomalous dimension of the fermion mass to be unity which are also very close to the ones obtained using the Schwinger......-Dyson approximation. We use the solutions to gain useful insight on the conformal window of the associated electric theory. A consistent picture emerges corroborating previous results obtained via different analytic methods and in agreement with first principle lattice explorations....

  14. Dual Campus High School

    Directory of Open Access Journals (Sweden)

    Carmen P. Mombourquette

    2013-04-01

    Full Text Available September 2010 witnessed the opening of the first complete dual campus high school in Alberta. Catholic Central High School, which had been in existence since 1967 in one building, now offered courses to students on two campuses. The “dual campus” philosophy was adopted so as to ensure maximum program flexibility for students. The philosophy, however, was destined to affect student engagement and staff efficacy as the change in organizational structure, campus locations, and course availability was dramatic. Changing school organizational structure also had the potential of affecting student achievement. A mixed-methods study utilizing engagement surveys, efficacy scales, and interviews with students and teachers was used to ascertain the degree of impact. The results of the study showed that minimal impact occurred to levels of student engagement, minor negative impact to staff efficacy, and a slight increase to student achievement results.

  15. Dual Double Field Theory

    CERN Document Server

    Bergshoeff, Eric A; Penas, Victor A; Riccioni, Fabio

    2016-01-01

    We present the dual formulation of double field theory at the linearized level. This is a classically equivalent theory describing the duals of the dilaton, the Kalb-Ramond field and the graviton in a T-duality or O(D,D) covariant way. In agreement with previous proposals, the resulting theory encodes fields in mixed Young-tableau representations, combining them into an antisymmetric 4-tensor under O(D,D). In contrast to previous proposals, the theory also requires an antisymmetric 2-tensor and a singlet, which are not all pure gauge. The need for these additional fields is analogous to a similar phenomenon for "exotic" dualizations, and we clarify this by comparing with the dualizations of the component fields. We close with some speculative remarks on the significance of these observations for the full non-linear theory yet to be constructed.

  16. Dual-comb MIXSEL

    Science.gov (United States)

    Link, S. M.; Zaugg, C. A.; Klenner, A.; Mangold, M.; Golling, M.; Tilma, B. W.; Keller, U.

    2015-03-01

    We present a single semiconductor disk laser simultaneously emitting two different gigahertz modelocked pulse trains. A birefringent crystal inside a modelocked integrated external-cavity surface-emitting laser (MIXSEL) separates the cavity beam into two spatially separated beams with perpendicular polarizations on the MIXSEL chip. This MIXSEL then generates two orthogonally polarized collinear modelocked pulse trains from one simple straight cavity. Superimposing the beams on a photo detector creates a microwave beat signal, representing a strikingly simple setup to down-convert the terahertz optical frequencies into the electronically accessible microwave regime. This makes the dual-comb MIXSEL scheme an ultra-compact and cost-efficient candidate for dual-comb spectroscopy applications.

  17. Engineering Encounters: Reverse Engineering

    Science.gov (United States)

    McGowan, Veronica Cassone; Ventura, Marcia; Bell, Philip

    2017-01-01

    This column presents ideas and techniques to enhance your science teaching. This month's issue shares information on how students' everyday experiences can support science learning through engineering design. In this article, the authors outline a reverse-engineering model of instruction and describe one example of how it looked in our fifth-grade…

  18. Dual-readout Calorimetry

    OpenAIRE

    Akchurin, N.; Bedeschi, F.; Cardini, A.; Cascella, M.; Cei, F.; Pedis, D.; Fracchia, S.; Franchino, S.; Fraternali, M.; Gaudio, G.; P. Genova; Hauptman, J.; La Rotonda, L.; Lee, S.; Livan, M.(INFN Sezione di Pavia, Pavia, Italy)

    2013-01-01

    The RD52 Project at CERN is a pure instrumentation experiment whose goal is to understand the fundamental limitations to hadronic energy resolution, and other aspects of energy measurement, in high energy calorimeters. We have found that dual-readout calorimetry provides heretofore unprecedented information event-by-event for energy resolution, linearity of response, ease and robustness of calibration, fidelity of data, and particle identification, including energy lost to binding energy in n...

  19. Dual-Schemata Model

    Science.gov (United States)

    Taniguchi, Tadahiro; Sawaragi, Tetsuo

    In this paper, a new machine-learning method, called Dual-Schemata model, is presented. Dual-Schemata model is a kind of self-organizational machine learning methods for an autonomous robot interacting with an unknown dynamical environment. This is based on Piaget's Schema model, that is a classical psychological model to explain memory and cognitive development of human beings. Our Dual-Schemata model is developed as a computational model of Piaget's Schema model, especially focusing on sensori-motor developing period. This developmental process is characterized by a couple of two mutually-interacting dynamics; one is a dynamics formed by assimilation and accommodation, and the other dynamics is formed by equilibration and differentiation. By these dynamics schema system enables an agent to act well in a real world. This schema's differentiation process corresponds to a symbol formation process occurring within an autonomous agent when it interacts with an unknown, dynamically changing environment. Experiment results obtained from an autonomous facial robot in which our model is embedded are presented; an autonomous facial robot becomes able to chase a ball moving in various ways without any rewards nor teaching signals from outside. Moreover, emergence of concepts on the target movements within a robot is shown and discussed in terms of fuzzy logics on set-subset inclusive relationships.

  20. Natural Gas for Advanced Dual-Fuel Combustion Strategies

    Science.gov (United States)

    Walker, Nicholas Ryan

    Natural gas fuels represent the next evolution of low-carbon energy feedstocks powering human activity worldwide. The internal combustion engine, the energy conversion device widely used by society for more than one century, is capable of utilizing advanced combustion strategies in pursuit of ultra-high efficiency and ultra-low emissions. Yet many emerging advanced combustion strategies depend upon traditional petroleum-based fuels for their operation. In this research the use of natural gas, namely methane, is applied to both conventional and advanced dual-fuel combustion strategies. In the first part of this work both computational and experimental studies are undertaken to examine the viability of utilizing methane as the premixed low reactivity fuel in reactivity controlled compression ignition, a leading advanced dual-fuel combustion strategy. As a result, methane is shown to be capable of significantly extending the load limits for dual-fuel reactivity controlled compression ignition in both light- and heavy-duty engines. In the second part of this work heavy-duty single-cylinder engine experiments are performed to research the performance of both conventional dual-fuel (diesel pilot ignition) and advanced dual-fuel (reactivity controlled compression ignition) combustion strategies using methane as the premixed low reactivity fuel. Both strategies are strongly influenced by equivalence ratio; diesel pilot ignition offers best performance at higher equivalence ratios and higher premixed methane ratios, whereas reactivity controlled compression ignition offers superior performance at lower equivalence ratios and lower premixed methane ratios. In the third part of this work experiments are performed in order to determine the dominant mode of heat release for both dual-fuel combustion strategies. By studying the dual-fuel homogeneous charge compression ignition and single-fuel spark ignition, strategies representative of autoignition and flame propagation

  1. Controlling the Focal Length and the Spot Size in Flying Optics by Dual-deformable-mirror-systems

    Institute of Scientific and Technical Information of China (English)

    ZHAO Quanzhong; CHENG Zhaogu; GAO Haijun; CHAI Xiongliang; LUO Hongxin

    2002-01-01

    The models of several dual-deformable-mirror-systems,which can control focal the length and the spot size in flying optics,were introduced and their operating principle and adjusting characteristics were analyzed.The simulation results indicate that dual-deformable-mirror-systems can control the focal length and the spot size.This research is a good guidance to engineering application of dual-deformable-mirror-systems.

  2. Analysis on dynamic characteristics of aero-engine rolling bearing/dual-rotor system%航空发动机滚动轴承-双转子系统动态特性分析

    Institute of Scientific and Technical Information of China (English)

    邓四二; 付金辉; 王燕霜; 杨海生

    2013-01-01

    The dynamic model of dual-rotor coupling system which included rolling bearing dynamics and rotor dynamics was established. Fine integral method and predict-correct Adams-Bashforth-Moulton multi-step method were used to solve the nonlinear dynamic equations of dual-rotor system. Then the influences of bearing structural parameters on dynamic response of rotors were studied. The result shows: (1) the displacement of rotors can be decreased and the stability of rotors can be improved by reducing radical clearance of inter-shaft bearing, but the slide ratio of cage would increase when the radial clearance decreases, so the radial clearance should be selected properly; the slide ratio of cage would decrease and the displacement of rotors would increase when the rollers of inter-shaft bearing are reduced; (2) the displacement and stability of rotors can be optimized when the groove curvature radius coefficients of rings and radial clearance of supporting bearings are decreased, and the stability of rotor would be improved when the rolling elements of bearings are increased.%在滚动轴承动力学和转子动力学分析基础上,建立了含滚动轴承动力学与转子动力学耦合以及高、低压转子间耦合的滚动轴承-双转子系统动力学方程,采用精细积分法和预估-校正Adams-Bashforth-Moulton多步法相结合的算法,对航空发动机滚动轴承-双转子系统非线性动力学方程进行求解,并对滚动轴承结构参数与转子动态特性的关系进行了理论分析.分析结果表明:①中介轴承径向游隙较小时转子系统振动量较小且转子运行较平稳,但中介轴承保持架打滑率会有所提高,应合理选取中介轴承的径向游隙值;中介轴承滚子数量对转子运转稳定性有较大影响,减小中介轴承滚子数量可降低保持架打滑率,但转子系统的振动量会增大;②支承轴承内、外沟曲率半径系数及径向游隙较小时转子系统的振动量较

  3. Fibrotic remodeling of the extracellular matrix through a novel (engineered, dual-function antibody reactive to a cryptic epitope on the N-terminal 30 kDa fragment of fibronectin.

    Directory of Open Access Journals (Sweden)

    Maryada Sharma

    Full Text Available Fibrosis is characterized by excessive accumulation of scar tissue as a result of exaggerated deposition of extracellular matrix (ECM, leading to tissue contraction and impaired function of the organ. Fibronectin (Fn is an essential component of the ECM, and plays an important role in fibrosis. One such fibrotic pathology is that of proliferative vitreoretinopathy (PVR, a sight-threatening complication which develops as a consequence of failure of surgical repair of retinal detachment. Such patients often require repeated surgeries for retinal re-attachment; therefore, a preventive measure for PVR is of utmost importance. The contractile membranes formed in PVR, are composed of various cell types including the retinal pigment epithelial cells (RPE; fibronectin is an important constituent of the ECM surrounding these cells. Together with the vitreous, fibronectin creates microenvironments in which RPE cells proliferate. We have successfully developed a dual-action, fully human, fibronectin-specific single chain variable fragment antibody (scFv termed Fn52RGDS, which acts in two ways: i binds to cryptic sites in fibronectin, and thereby prevents its self polymerization/fibrillogenesis, and ii interacts with the cell surface receptors, ie., integrins (through an attached "RGD" sequence tag, and thereby blocks the downstream cell signaling events. We demonstrate the ability of this antibody to effectively reduce some of the hallmark features of fibrosis--migration, adhesion, fibronectin polymerization, matrix metalloprotease (MMP expression, as well as reduction of collagen gel contraction (a model of fibrotic tissue remodeling. The data suggests that the antibody can be used as a rational, novel anti-fibrotic candidate.

  4. Aircraft Engine Sensor Fault Diagnostics Through Dual-Channel Sensor Measurements Based on a Bank of Hybrid Kalman Filters%基于混合卡尔曼滤波器组的航空发动机双通道传感器故障检测

    Institute of Scientific and Technical Information of China (English)

    张书刚; 郭迎清; 陆军

    2012-01-01

    Based on a bank of hybrid Kalman filters which are hybrids of a nonlinear on-board engine model (NOBEM) and piecewise linear Kalman fillers, a civil aircraft engine sensor fault diagnostics system which utilizes dual -channel sensor measurements is developed. Principles and algorithms of sensor fault detection, isolation and accommodation are given. By this system applied to some typical civil turbo-fan engine sensor faults, simulation results show that the diagnostic effectiveness of the system is maintained to avoid false alarms as the health of the engine degrades over time through a simple process: by feeding the health degradation values into the NUBEM and not changing the parameters of the linear Kalman filters. The update process, which can be completed automatically online to save time and effort, is feasible in the real application environment.%基于机载非线性模型与分段线性卡尔曼滤波器混合组成的混合卡尔曼滤波器组,结合双通道传感器的特点,建立了民用航空发动机传感器故障诊断系统;给出故障诊断原理及算法的同时,将该系统应用于民用涡扇发动机传感器常见典型故障进行了仿真;仿真结果表明,诊断系统可以在发动机发生健康蜕化后,通过只简单更新机载模型的蜕化因子,而保持线性卡尔曼滤波器的参数不变,便能准确地检测和隔离各类传感器故障而不发生误报;该更新过程可以在线自动完成,省时省力,易于工程实现.

  5. IDEALIZED ENGINE EMISSIONS RESULTING FROM THE COMBUSTION OF GASOLINE SUPPLEMENTED WITH LPG

    Directory of Open Access Journals (Sweden)

    Cenk SAYIN

    2006-02-01

    Full Text Available In the internal combustion engines, the studies to reduce brake specific fuel consumption and exhaust emissions to the lowest level are the start of the investigations on the dual fuel engines. In this study, the changes in the exhaust emissions of the dual fuel (gasoline + LPG at different ratios have been calculated using a computer program and the results are discussed.

  6. An Alternative Ice Protection System for Turbine Engine Inlets Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal presents a dual approach to the development and certification of an alternative system for ice protection of turbine engine inlets. It combines a new...

  7. Layered Systems Engineering Engines

    Science.gov (United States)

    Breidenthal, Julian C.; Overman, Marvin J.

    2009-01-01

    A notation is described for depicting the relationships between multiple, contemporaneous systems engineering efforts undertaken within a multi-layer system-of-systems hierarchy. We combined the concepts of remoteness of activity from the end customer, depiction of activity on a timeline, and data flow to create a new kind of diagram which we call a "Layered Vee Diagram." This notation is an advance over previous notations because it is able to be simultaneously precise about activity, level of granularity, product exchanges, and timing; these advances provide systems engineering managers a significantly improved ability to express and understand the relationships between many systems engineering efforts. Using the new notation, we obtain a key insight into the relationship between project duration and the strategy selected for chaining the systems engineering effort between layers, as well as insights into the costs, opportunities, and risks associated with alternate chaining strategies.

  8. Alexander Duals of Multipermutohedron Ideals

    Indian Academy of Sciences (India)

    Ajay Kumar; Chanchal Kumar

    2014-02-01

    An Alexander dual of a multipermutohedron ideal has many combinatorial properties. The standard monomials of an Artinian quotient of such a dual correspond bijectively to some -parking functions, and many interesting properties of these Artinian quotients are obtained by Postnikov and Shapiro (Trans. Am. Math. Soc. 356 (2004) 3109–3142). Using the multigraded Hilbert series of an Artinian quotient of an Alexander dual of multipermutohedron ideals, we obtained a simple proof of Steck determinant formula for enumeration of -parking functions. A combinatorial formula for all the multigraded Betti numbers of an Alexander dual of multipermutohedron ideals are also obtained.

  9. Engineer Ethics

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dae Sik; Kim, Yeong Pil; Kim, Yeong Jin

    2003-03-15

    This book tells of engineer ethics such as basic understanding of engineer ethics with history of engineering as a occupation, definition of engineering and specialized job and engineering, engineer ethics as professional ethics, general principles of ethics and its limitation, ethical theory and application, technique to solve the ethical problems, responsibility, safety and danger, information engineer ethics, biotechnological ethics like artificial insemination, life reproduction, gene therapy and environmental ethics.

  10. Dual massive gravity

    Energy Technology Data Exchange (ETDEWEB)

    Morand, Kevin, E-mail: Kevin.Morand@lmpt.univ-tours.fr [Laboratoire de Mathematiques et Physique Theorique, Universite Francois-Rabelais Tours, Federation Denis Poisson - CNRS, Parc de Grandmont, 37200 Tours (France); Solodukhin, Sergey N., E-mail: Sergey.Solodukhin@lmpt.univ-tours.fr [Laboratoire de Mathematiques et Physique Theorique, Universite Francois-Rabelais Tours, Federation Denis Poisson - CNRS, Parc de Grandmont, 37200 Tours (France)

    2012-08-29

    The linearized massive gravity in three dimensions, over any maximally symmetric background, is known to be presented in a self-dual form as a first order equation which encodes not only the massive Klein-Gordon type field equation but also the supplementary transverse-traceless conditions. We generalize this construction to higher dimensions. The appropriate dual description in d dimensions, additionally to a (non-symmetric) tensor field h{sub {mu}{nu}}, involves an extra rank-(d-1) field equivalently represented by the torsion rank-3 tensor. The symmetry condition for h{sub {mu}{nu}} arises on-shell as a consequence of the field equations. The action principle of the dual theory is formulated. The focus has been made on four dimensions. Solving one of the fields in terms of the other and putting back in the action one obtains two other equivalent formulations of the theory in which the action is quadratic in derivatives. In one of these representations the theory is formulated entirely in terms of a rank-2 non-symmetric tensor h{sub {mu}{nu}}. This quadratic theory is not identical to the Fierz-Pauli theory and contains the coupling between the symmetric and antisymmetric parts of h{sub {mu}{nu}}. Nevertheless, the only singularity in the propagator is the same as in the Fierz-Pauli theory so that only the massive spin-2 particle is propagating. In the other representation, the theory is formulated in terms of the torsion rank-3 tensor only. We analyze the conditions which follow from the field equations and show that they restrict to 5 degrees of freedom thus producing an alternative description to the massive spin-2 particle. A generalization to higher dimensions is suggested.

  11. Towards a Dual Approach

    DEFF Research Database (Denmark)

    Holli, Anne Maria; Harder, Mette Marie Stæhr

    2016-01-01

    countries acknowledged as forerunners in gender equality, which also have ‘fairly strong’ parliamentary standing committees. The results show that both committees on gender equality can be regarded as ‘feminist’ in character and both interact with relevant civil society organisations. Their impact......Drawing on insights from state feminism and legislative studies on parliamentary committees, this article develops a dual approach for the comparative analysis of committees on gender equality. Empirically, it compares the standing committees on gender equality in Denmark and Finland, two Nordic...

  12. Dual cure photocatalyst systems

    Energy Technology Data Exchange (ETDEWEB)

    DeVoe, R.J.; Brown-Wensley, K.A.; Holmes, G.L.; Mathis, M.D.; McCormick, F.B.; Palazzotto, M.C.; Spurgeon, K.M. (Minnesota Mining and Mfg. Co., St. Paul, MN (USA). Corporate Research Labs.)

    1990-01-01

    A family of dual cure photocatalyst systems is being developed to be used in the solventless processing of organic coatings. The photocatalyst systems consist of organometallic compounds often in combination with other agents. Upon photolysis, the photocatalyst system generates a Lewis acid and a free radical. The Lewis acid can initiate the polymerization of epoxies or the addition of isocyanates and polyols to form polyurethanes while the free radical can initiate the polymerization of acrylates. The performance of the various photocatalyst systems will be compared on the basis of the physical properties of the cured compositions they produce. 17 figs.

  13. Effects of dual tasks and dual-task training on postural stability: a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Ghai S

    2017-03-01

    Full Text Available Shashank Ghai,1,2 Ishan Ghai,3 Alfred O Effenberg1 1Institute of Sports Science, Leibniz University, Hannover, Germany; 2Department of Sports Science, University of Waikato, Hamilton, New Zealand; 3School of Engineering & Life Sciences, Jacobs University, Bremen, Germany Abstract: The use of dual-task training paradigm to enhance postural stability in patients with balance impairments is an emerging area of interest. The differential effects of dual tasks and dual-task training on postural stability still remain unclear. A systematic review and meta-analysis were conducted to analyze the effects of dual task and training application on static and dynamic postural stability among various population groups. Systematic identification of published literature was performed adhering to Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA guidelines, from inception until June 2016, on the online databases Scopus, PEDro, MEDLINE, EMBASE, and SportDiscus. Experimental studies analyzing the effects of dual task and dual-task training on postural stability were extracted, critically appraised using PEDro scale, and then summarized according to modified PEDro level of evidence. Of 1,284 records, 42 studies involving 1,480 participants met the review’s inclusion criteria. Of the studies evaluating the effects of dual-task training on postural stability, 87.5% of the studies reported significant enhancements, whereas 30% of the studies evaluating acute effects of dual tasks on posture reported significant enhancements, 50% reported significant decrements, and 20% reported no effects. Meta-analysis of the pooled studies revealed moderate but significant enhancements of dual-task training in elderly participants (95% CI: 1.16–2.10 and in patients suffering from chronic stroke (-0.22 to 0.86. The adverse effects of complexity of dual tasks on postural stability were also revealed among patients with multiple sclerosis (-0.74 to 0

  14. Four Engineers...

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    There are four engineers traveling in a car;a mechanical engineer,a chemical engi-neer,an electrical engineer and a comput-er engineer.The car breaks down.“Sounds to me as if the pistons have seized.We ll have to strip down the engine before we canget the car working again,”says the mechanical

  15. Low emission fuel engine and method of operating same

    Energy Technology Data Exchange (ETDEWEB)

    Helmich, M.J.

    1990-09-11

    This patent describes a low emission duel fuel engine system. It comprises: a dual fuel engine having a combustion chamber; a fuel oil supply connected to the engine; a fuel gas supply connected to the engine; and means connected between the fuel oil supply and the engine for injecting fuel oil into the engine. The means connected between the engine and fuel oil supply limiting the injection of fuel oil to the combustion chamber to pilot ignition quantities only, wherein the limiting means includes means for limiting the injection of fuel oil such that the exhaust emission of NO{sub x} is at an emission rate of less than 1 GM/PH-HR, whereby the exhaust emission performance of the dual fuel engine is enhanced.

  16. Robust dual-response optimization

    NARCIS (Netherlands)

    Yanikoglu, Ihsan; den Hertog, Dick; Kleijnen, J.P.C.

    2016-01-01

    This article presents a robust optimization reformulation of the dual-response problem developed in response surface methodology. The dual-response approach fits separate models for the mean and the variance and analyzes these two models in a mathematical optimization setting. We use metamodels esti

  17. Dual-Credit in Kentucky

    Science.gov (United States)

    Stephenson, Lisa G.

    2013-01-01

    Credit-based transition programs provide high school students with opportunities to jump start their college education. The Kentucky Community and Technical College System (KCTCS) offers college credit through dual-credit programs. While KCTCS dual-credit offerings have been successful in helping high school students start their college education…

  18. Dual-core Itanium Processor

    CERN Multimedia

    2006-01-01

    Intel’s first dual-core Itanium processor, code-named "Montecito" is a major release of Intel's Itanium 2 Processor Family, which implements the Intel Itanium architecture on a dual-core processor with two cores per die (integrated circuit). Itanium 2 is much more powerful than its predecessor. It has lower power consumption and thermal dissipation.

  19. Dual Card,Double Happiness

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    As Christmas Day and New Year Day draw near, why not treat yourself with a smart digital gizmo. Then, the Samsung Dual-card Cellphone is what you are longing for. Samsung B5712C, the first dual-card model released by Samsung,

  20. Asymmetry in Dual Language Practice

    Directory of Open Access Journals (Sweden)

    Audrey Amrein

    2000-01-01

    Full Text Available The capacity for dual-language programs to deliver specific benefits to students with different primary and secondary language skills continues to be debated. Individuals favoring dual language assert that as it relies upon a reciprocal approach, dual language students acquire dual language proficiency without the need for teachers to translate from one language to another. By utilizing and conserving the language skills that students bring, dual language students also gain cross-cultural understandings and an expanded opportunity to realize academic success in the future. Research that explores whether these programs meet the needs of monolingual and bilingual students is limited. The intent of this study is not to criticize dual language practice. Instead, it is to describe a newly implemented dual language immersion program that exists and operates in Phoenix, Arizona. In particular, this study examines the practices of dual language teachers at Leigh Elementary School and the challenges encountered as school personnel worked to provide students with different primary and secondary language skills increased opportunities to learn.

  1. Benefits of Dual Language Education

    Science.gov (United States)

    Wallstrum, Kiara

    2009-01-01

    The focus of this paper examines how dual language education (DLE) programs are valuable. The literature shows that children do much more than just thrive in a dual language environment. According to research, children who are bilingual are cognitively, academically, intellectually, socially and verbally more advantaged than their monolingual…

  2. THE REDUCTION OF VIBRATIONS IN A CAR – THE PRINCIPLE OF PNEUMATIC DUAL MASS FLYWHEEL

    Directory of Open Access Journals (Sweden)

    Robert GREGA

    2014-09-01

    Full Text Available The dual-mass flywheel replaces the classic flywheel in such way that it is divided into two masses (the primary mass and the secondary mass, which are jointed together by means of a flexible interconnection. This kind of the flywheel solution enables to change resonance areas of the engine with regard to the engine dynamic behaviour what leads to a reduction of vibrations consequently. However, there is also a disadvantage of the dualmass flywheels. The disadvantage is its short-time durability. There was projected a new type of the dual-mass flywheel in the framework of our workplace in order to eliminate disadvantages of the present dual-mass flywheels, i.e. we projected the pneumatic dual-mass flywheel, taking into consideration our experiences obtained during investigation of vibrations.

  3. 76 FR 39795 - Special Conditions: Pratt and Whitney Canada Model PT6C-67E Turboshaft Engine

    Science.gov (United States)

    2011-07-07

    ... includes a dual channel full authority digital electronic control. The engine will incorporate a novel or... twin-engine helicopter. The helicopter manufacturer anticipates that for search and rescue...

  4. Engineering holographic phase diagrams

    Science.gov (United States)

    Chen, Jiunn-Wei; Dai, Shou-Huang; Maity, Debaprasad; Zhang, Yun-Long

    2016-10-01

    By introducing interacting scalar fields, we tried to engineer physically motivated holographic phase diagrams which may be interesting in the context of various known condensed matter systems. We introduce an additional scalar field in the bulk which provides a tunable parameter in the boundary theory. By exploiting the way the tuning parameter changes the effective masses of the bulk interacting scalar fields, desired phase diagrams can be engineered for the boundary order parameters dual to those scalar fields. We give a few examples of generating phase diagrams with phase boundaries which are strikingly similar to the known quantum phases at low temperature such as the superconducting phases. However, the important difference is that all the phases we have discussed are characterized by neutral order parameters. At the end, we discuss if there exists any emerging scaling symmetry associated with a quantum critical point hidden under the dome in this phase diagram.

  5. Power generation using coir-pith and wood derived producer gas in diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Ramadhas, A.S.; Jayaraj, S.; Muraleedharan, C. [Department of Mechanical Engineering, National Institute of Technology Calicut, Calicut-673 601, Kerala State (India)

    2006-10-15

    Partial combustion of biomass in the gasifier generates producer gas that can be used for heating purposes and as supplementary or sole fuel in internal combustion engines. In this study, the potential of coir-pith and wood chips as the feedstock for gasifier is analyzed. The performance of the gasifier-engine system is analyzed by running the engine for various producer gas-air flow ratios and at different load conditions. The system is experimentally optimized with respect to maximum diesel savings and lower emissions in the dual fuel mode operation while using coir-pith and wood chips separately. The performance and emission characteristics of the dual fuel engine are compared with that of diesel engine at different load conditions. Specific energy consumption in the dual fuel mode of operation is found to be in the higher side at all load conditions. The brake thermal efficiency of the engine while using wood chips in the dual mode operation is higher than that of coir-pith. The CO emission is higher in the case of dual fuel mode of operation as compared to that of diesel mode. In the dual fuel mode of operation, the higher diesel savings is achieved while using wood chips as compared to that of coir-pith. The comparison of the performance and emission characteristics of the dual fuel engine with diesel engine is also described. (author)

  6. Dual-horizon Peridynamics

    CERN Document Server

    Ren, Huilong; Cai, Yongchang; Rabczuk, Timon

    2015-01-01

    In this paper we develop a new Peridynamic approach that naturally includes varying horizon sizes and completely solves the "ghost force" issue. Therefore, the concept of dual-horizon is introduced to consider the unbalanced interactions between the particles with different horizon sizes. The present formulation is proved to fulfill both the balances of linear momentum and angular momentum. Neither the "partial stress tensor" nor the "`slice" technique are needed to ameliorate the ghost force issue in \\cite{Silling2014}. The consistency of reaction forces is naturally fulfilled by a unified simple formulation. The method can be easily implemented to any existing peridynamics code with minimal changes. A simple adaptive refinement procedure is proposed minimizing the computational cost. The method is applied here to the three Peridynamic formulations, namely bond based, ordinary state based and non-ordinary state based Peridynamics. Both two- and three- dimensional examples including the Kalthof-Winkler experi...

  7. Dual Criteria Decisions

    DEFF Research Database (Denmark)

    Andersen, Steffen; Harrison, Glenn W.; Lau, Morten Igel;

    2014-01-01

    The most popular models of decision making use a single criterion to evaluate projects or lotteries. However, decision makers may actually consider multiple criteria when evaluating projects. We consider a dual criteria model from psychology. This model integrates the familiar tradeoffs between...... risk and utility that economists traditionally assume, allowance for rank-dependent decision weights, and consideration of income thresholds. We examine the issues involved in full maximum likelihood estimation of the model using observed choice data. We propose a general method for integrating...... the multiple criteria, using the logic of mixture models, which we believe is attractive from a decision-theoretic and statistical perspective. The model is applied to observed choices from a major natural experiment involving intrinsically dynamic choices over highly skewed outcomes. The evidence points...

  8. Engineering ceramics

    CERN Document Server

    Bengisu, Murat

    2001-01-01

    This is a comprehensive book applying especially to junior and senior engineering students pursuing Materials Science/ Engineering, Ceramic Engineering and Mechanical Engineering degrees. It is also a reference book for other disciplines such as Chemical Engineering, Biomedical Engineering, Nuclear Engineering and Environmental Engineering. Important properties of most engineering ceramics are given in detailed tables. Many current and possible applications of engineering ceramics are described, which can be used as a guide for materials selection and for potential future research. While covering all relevant information regarding raw materials, processing properties, characterization and applications of engineering ceramics, the book also summarizes most recent innovations and developments in this field as a result of extensive literature search.

  9. Engineering and Software Engineering

    Science.gov (United States)

    Jackson, Michael

    The phrase ‘software engineering' has many meanings. One central meaning is the reliable development of dependable computer-based systems, especially those for critical applications. This is not a solved problem. Failures in software development have played a large part in many fatalities and in huge economic losses. While some of these failures may be attributable to programming errors in the narrowest sense—a program's failure to satisfy a given formal specification—there is good reason to think that most of them have other roots. These roots are located in the problem of software engineering rather than in the problem of program correctness. The famous 1968 conference was motivated by the belief that software development should be based on “the types of theoretical foundations and practical disciplines that are traditional in the established branches of engineering.” Yet after forty years of currency the phrase ‘software engineering' still denotes no more than a vague and largely unfulfilled aspiration. Two major causes of this disappointment are immediately clear. First, too many areas of software development are inadequately specialised, and consequently have not developed the repertoires of normal designs that are the indispensable basis of reliable engineering success. Second, the relationship between structural design and formal analytical techniques for software has rarely been one of fruitful synergy: too often it has defined a boundary between competing dogmas, at which mutual distrust and incomprehension deprive both sides of advantages that should be within their grasp. This paper discusses these causes and their effects. Whether the common practice of software development will eventually satisfy the broad aspiration of 1968 is hard to predict; but an understanding of past failure is surely a prerequisite of future success.

  10. Dual-band double-negative-index fishnet metamaterial at millimeter-waves.

    Science.gov (United States)

    Navarro-Cía, Miguel; García-Meca, Carlos; Beruete, Miguel; Martínez, Alejandro; Sorolla, Mario

    2011-11-01

    An effective negative refractive index (NRI) is demonstrated and experimentally verified for the first two propagation bands of a fishnet-like metamaterial at millimeter-wave frequencies. The dual-band NRI behavior is achieved by engineering the diffraction order (±1, ±1) associated with the internal mode supported between holey layers to correspond with the second propagation band. In addition to the experimental interferometric technique that accounts for the handedness of the propagation, numerical results are given to predict the dual-band effective NRI and to confirm dual-band negative refraction for a prism composed of the proposed metamaterial.

  11. Optimal dual-fuel propulsion for minimum inert weight or minimum fuel cost

    Science.gov (United States)

    Martin, J. A.

    1973-01-01

    An analytical investigation of single-stage vehicles with multiple propulsion phases has been conducted with the phasing optimized to minimize a general cost function. Some results are presented for linearized sizing relationships which indicate that single-stage-to-orbit, dual-fuel rocket vehicles can have lower inert weight than similar single-fuel rocket vehicles and that the advantage of dual-fuel vehicles can be increased if a dual-fuel engine is developed. The results also indicate that the optimum split can vary considerably with the choice of cost function to be minimized.

  12. Dual Functional Star Polymers for Lubricants

    Energy Technology Data Exchange (ETDEWEB)

    Cosimbescu, Lelia; Robinson, Joshua W.; Zhou, Yan; Qu, Jun

    2016-09-12

    Star-shaped poly(alkyl methacrylate)s (PAMAs) with a 3-arm architecture were designed, prepared and their performance as a dual additive (viscosity index improver and friction modifier) for engine oils was evaluated. Furthermore, the structure-property relationships between macromolecular structure and lubricant performance were studied. Several co-polymers of dodecylmethacrylate with polar methacrylates in various amounts and various topologies, were synthesized as model compounds. Star polymers with a polar content of at least 10% effectively reduced the friction coefficient in both mixed and boundary lubrication regime only in block or tapered block topology. However, a polar content of 20% was efficient in reducing friction in both random and block topologies.

  13. Mechanical engineering

    CERN Document Server

    Darbyshire, Alan

    2010-01-01

    Alan Darbyshire's best-selling text book provides five-star high quality content to a potential audience of 13,000 engineering students. It explains the most popular specialist units of the Mechanical Engineering, Manufacturing Engineering and Operations & Maintenance Engineering pathways of the new 2010 BTEC National Engineering syllabus. This challenging textbook also features contributions from specialist lecturers, ensuring that no stone is left unturned.

  14. Dual of QCD with One Adjoint Fermion

    DEFF Research Database (Denmark)

    Mojaza, Matin; Nardecchia, Marco; Pica, Claudio;

    2011-01-01

    We construct the magnetic dual of QCD with one adjoint Weyl fermion. The dual is a consistent solution of the 't Hooft anomaly matching conditions, allows for flavor decoupling and remarkably constitutes the first nonsupersymmetric dual valid for any number of colors. The dual allows to bound the...

  15. The Man of Dual Nationality.

    Science.gov (United States)

    Abe, Yoshio

    1985-01-01

    Presents an English translation of the first few pages, set in a Japanese internment camp in the U.S. during World War II, of a Japanese novel about the problems of dual nationality and personal identity. (KH)

  16. Lp-dual Quermassintegral sums

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this paper,we first introduce a concept of L_p-dual Quermassintegral sum function of convex bodies and establish the polar projection Minkowski inequality and the polar projection Aleksandrov-Fenchel inequality for L_p-dual Quermassintegral sums.Moreover,by using Lutwak’s width-integral of index i,we establish the L_p-Brunn-Minkowski inequality for the polar mixed projec- tion bodies.As applications,we prove some interrelated results.

  17. Dual pairs in fluid dynamics

    CERN Document Server

    Gay-Balmaz, François

    2010-01-01

    This paper is a rigorous study of the dual pair structure of the ideal fluid and the dual pair structure for the $n$-dimensional Camassa-Holm (EPDiff) equation, including the proofs of the necessary transitivity results. In the case of the ideal fluid, we show that a careful definition of the momentum maps leads naturally to central extensions of diffeomorphism groups such as the group of quantomorphisms and the Ismagilov central extension.

  18. DESIGN OF A DUAL KEYBOARD

    OpenAIRE

    V. Ragavi; G. Geetha

    2013-01-01

    The design of a computer keyboard with dual function is proposed. This computer keyboard called Dual Keyboard can function both as a normal keyboard and as a pressure sensitive keyboard. The proposed device has a switch that decides the function. The keyboard makes use of sensors placed beneath the keys to measure the pressure applied on the key by the user. This device has many applications. In this study, it is applied to mitigate Denial of Service (DoS) attack.

  19. Generator gas as a fuel to power a diesel engine

    Directory of Open Access Journals (Sweden)

    Tutak Wojciech

    2014-01-01

    Full Text Available The results of gasification process of dried sewage sludge and use of generator gas as a fuel for dual fuel turbocharged compression ignition engine are presented. The results of gasifying showed that during gasification of sewage sludge is possible to obtain generator gas of a calorific value in the range of 2.15  2.59 MJ/m3. It turned out that the generator gas can be effectively used as a fuel to the compression ignition engine. Because of gas composition, it was possible to run engine with partload conditions. In dual fuel operation the high value of indicated efficiency was achieved equal to 35%, so better than the efficiency of 30% attainable when being fed with 100% liquid fuel. The dual fuel engine version developed within the project can be recommended to be used in practice in a dried sewage sludge gasification plant as a dual fuel engine driving the electric generator loaded with the active electric power limited to 40 kW (which accounts for approx. 50% of its rated power, because it is at this power that the optimal conditions of operation of an engine dual fuel powered by liquid fuel and generator gas are achieved. An additional advantage is the utilization of waste generated in the wastewater treatment plant.

  20. Fast dual tomography

    Science.gov (United States)

    Carrion, Philip M.

    1990-09-01

    This paper can be considered as a continuation of the work by Carrion and Carneiro (1989), where a generalized approach to linearized inversion of geophysical data was developed. Their method allows one to incorporate virtually any constraints in the inversion and reformulate the problem in the dual space of Langrangian multipliers (see also Carrion, 1989a). The constrained tomography makes traveltime inversion robust: it automatically rejects “bad data” which correspond to solutions beyond the chosen constraints and allows one to start inversion with an arbitrary chosen initial model.In this paper, I will derive basic formulas for constrained tomographic imaging that can be used in such areas of geophysics as global mapping of the earth interior, exploration geophysics, etc. The method is fast: an example that will be shown in the paper took only 6 min. of VAX CPU time. Had the conventional least-squares matrix inversion been used it would have taken more than 10 hours of the CPU time to solve the same problem.

  1. Fast dual tomography

    Energy Technology Data Exchange (ETDEWEB)

    Carrion, P.M. (PPPG/UFBA - Campus Universitario da Federacao, Salvador-Bahia (Brazil))

    1990-09-01

    This paper can be considered as a continuation of the work by Carrion and Carneiro (1989), where a generalized approach to linearized inversion of geophysical data was developed. Their method allows one to incorporate virtually any constraints in the inversion and reformulate the problem in the dual space of Langrangian multipliers (see also Carrion, 1989a). The constrained tomography makes traveltime inversion robust: it automatically rejects bad data which correspond to solutions beyond the chosen constraints and allows one to start inversion with an arbitrary chosen initial model. In this paper, the author derives basic formulas for constrained tomographic imaging that can be used in such areas of geophysics as global mapping of the earth interior, exploration geophysics, etc. The method is fast: an example that will be shown in the paper took only 6 min. of VAX CPU time. Had the conventional least-squares matrix inversion been used it would have taken more than 10 hours of the CPU time to solve the same problem.

  2. Homogeneous M2 duals

    CERN Document Server

    Figueroa-O'Farrill, José

    2015-01-01

    Motivated by the search for new gravity duals to M2 branes with $N>4$ supersymmetry --- equivalently, M-theory backgrounds with Killing superalgebra $\\mathfrak{osp}(N|4)$ for $N>4$ --- we classify (except for a small gap) homogeneous M-theory backgrounds with symmetry Lie algebra $\\mathfrak{so}(n) \\oplus \\mathfrak{so}(3,2)$ for $n=5,6,7$. We find that there are no new backgrounds with $n=6,7$ but we do find a number of new (to us) backgrounds with $n=5$. All backgrounds are metrically products of the form $\\operatorname{AdS}_4 \\times P^7$, with $P$ riemannian and homogeneous under the action of $\\operatorname{SO}(5)$, or $S^4 \\times Q^7$ with $Q$ lorentzian and homogeneous under the action of $\\operatorname{SO}(3,2)$. At least one of the new backgrounds is supersymmetric (albeit with only $N=2$) and we show that it can be constructed from a supersymmetric Freund--Rubin background via a Wick rotation. Two of the new backgrounds have only been approximated numerically.

  3. Comportamento de um motor de ignição por compressão trabalhando com óleo Diesel e gás natural A dual fuel compression ignition engine performance, running with Diesel fuel and natural gas

    Directory of Open Access Journals (Sweden)

    José F. Schlosser

    2004-12-01

    Full Text Available A previsível escassez de petróleo aliada a uma consciência ecológica está levando pesquisadores a procurar novas fontes de energia e processos de combustão mais eficientes e menos poluentes. Entre os combustíveis menos poluentes está o gás natural, cujo consumo aumenta ano a ano. Os motores de combustão interna são transformadores de energia que têm baixa eficiência de conversão. Este trabalho avaliou um motor Diesel, bicombustível, movido a Diesel e gás natural. Nesse motor, a energia provém, basicamente, da combustão do gás natural. O Diesel tem a função de produzir o início da combustão do gás, que é o combustível principal. Assim, haverá uma substituição parcial de óleo Diesel por gás natural, aumentando o rendimento da combustão. Inicialmente, foi feito um ensaio-testemunha, somente com óleo Diesel e após foram feitos ensaios, com três repetições, para variadas proporções de óleo Diesel, gás natural e ângulos de avanço da injeção. O melhor desempenho foi obtido para 22% de óleo Diesel em relação ao máximo débito da bomba injetora e 13 L min-1 de gás natural com ângulo de avanço de injeção original (21º. Nesse caso, a potência média aumentou 14%, e o consumo específico (medido em valores monetários diminuiu 46% em relação ao ensaio-testemunha.The foresight of a petroleum shortage and an ecological conscience is moving scientists to look for new sources of energy and to develop more efficient combustion processes and reduced emissions. Natural gas is a reduced emission fuel, whose consumption increases every year. The present work evaluates a dual fuel compression ignition engine. The major portion of the fuel burned is natural gas. The Diesel fuel acts as combustion starter, which ignites under the compression heat. Diesel fuel is used only as an ignition source. The partial substitution of Diesel fuel by natural gas increases the combustion efficiency and achieves significant

  4. Engineering Cartilage

    Science.gov (United States)

    ... Research Matters NIH Research Matters March 3, 2014 Engineering Cartilage Artistic rendering of human stem cells on ... situations has been a major goal in tissue engineering. Cartilage contains water, collagen, proteoglycans, and chondrocytes. Collagens ...

  5. Industrial Engineering

    DEFF Research Database (Denmark)

    Karlsson, Christer

    2015-01-01

    Industrial engineering is a discipline that is concerned with increasing the effectiveness of (primarily) manufacturing and (occasionally).......Industrial engineering is a discipline that is concerned with increasing the effectiveness of (primarily) manufacturing and (occasionally)....

  6. Governing Engineering

    DEFF Research Database (Denmark)

    Buch, Anders

    2011-01-01

    Abstract: Most people agree that our world faces daunting problems and, correctly or not, technological solutions are seen as an integral part of an overall solution. But what exactly are the problems and how does the engineering ‘mind set’ frame these problems? This chapter sets out to unravel...... dominant perspectives in challenge perception in engineering in the US and Denmark. Challenge perception and response strategies are closely linked through discursive practices. Challenge perceptions within the engineering community and the surrounding society are thus critical for the shaping...... of engineering education and the engineering profession. Through an analysis of influential reports and position papers on engineering and engineering education the chapter sets out to identify how engineering is problematized and eventually governed. Drawing on insights from governmentality studies the chapter...

  7. Governing Engineering

    DEFF Research Database (Denmark)

    Buch, Anders

    2012-01-01

    Most people agree that our world face daunting problems and, correctly or not, technological solutions are seen as an integral part of an overall solution. But what exactly are the problems and how does the engineering ‘mind set’ frame these problems? This chapter sets out to unravel dominant...... perspectives in challenge per-ception in engineering in the US and Denmark. Challenge perception and response strategies are closely linked through discursive practices. Challenge perceptions within the engineering community and the surrounding society are thus critical for the shaping of engineering education...... and the engineering profession. Through an analysis of influential reports and position papers on engineering and engineering education the chapter sets out to identify how engineering is problematized and eventually governed. Drawing on insights from governmentality studies the chapter strives to elicit the bodies...

  8. Computer Engineers.

    Science.gov (United States)

    Moncarz, Roger

    2000-01-01

    Looks at computer engineers and describes their job, employment outlook, earnings, and training and qualifications. Provides a list of resources related to computer engineering careers and the computer industry. (JOW)

  9. Biochemical Engineering.

    Science.gov (United States)

    Dunnill, P.

    1979-01-01

    Biochemical engineering as a scientific discipline is becoming accepted in England and is drawing many young men and women to its ranks. This article focuses on how engineering came to embrace the biological sciences. (Author/SA)

  10. Engineering _ litteraturliste

    DEFF Research Database (Denmark)

    Sillasen, Martin Krabbe; Daugbjerg, Peer; Nielsen, Keld

    2017-01-01

    Litteraturliste udarbejdet som grundlag for artiklen ”Engineering – svaret på naturfagenes udfordringer?”......Litteraturliste udarbejdet som grundlag for artiklen ”Engineering – svaret på naturfagenes udfordringer?”...

  11. Prosthetic Engineering

    Science.gov (United States)

    ... Overview CoE for Limb Loss Prevention and Prosthetic Engineering Menu Menu VA Center of Excellence for Limb ... ZIP code here Enter ZIP code here Prosthetic Engineering - Overview Our aim is to improve prosthetic prescription ...

  12. Electromagnetic linear machines with dual Halbach array design and analysis

    CERN Document Server

    Yan, Liang; Peng, Juanjuan; Zhang, Lei; Jiao, Zongxia

    2017-01-01

    This book extends the conventional two-dimensional (2D) magnet arrangement into 3D pattern for permanent magnet linear machines for the first time, and proposes a novel dual Halbach array. It can not only effectively increase the radial component of magnetic flux density and output force of tubular linear machines, but also significantly reduce the axial flux density, radial force and thus system vibrations and noises. The book is also the first to address the fundamentals and provide a summary of conventional arrays, as well as novel concepts for PM pole design in electric linear machines. It covers theoretical study, numerical simulation, design optimization and experimental works systematically. The design concept and analytical approaches can be implemented to other linear and rotary machines with similar structures. The book will be of interest to academics, researchers, R&D engineers and graduate students in electronic engineering and mechanical engineering who wish to learn the core principles, met...

  13. Engineering Motion

    Science.gov (United States)

    Tuttle, Nicole; Stanley, Wendy; Bieniek, Tracy

    2016-01-01

    For many teachers, engineering can be intimidating; teachers receive little training in engineering, particularly those teaching early elementary students. In addition, the necessity of differentiating for students with special needs can make engineering more challenging to teach. This article describes a professional development program…

  14. Engineering Motion

    Science.gov (United States)

    Tuttle, Nicole; Stanley, Wendy; Bieniek, Tracy

    2016-01-01

    For many teachers, engineering can be intimidating; teachers receive little training in engineering, particularly those teaching early elementary students. In addition, the necessity of differentiating for students with special needs can make engineering more challenging to teach. This article describes a professional development program…

  15. Imitation and Innovation: The Dual Engines of Cultural Learning.

    Science.gov (United States)

    Legare, Cristine H; Nielsen, Mark

    2015-11-01

    Imitation and innovation work in tandem to support cultural learning in children and facilitate our capacity for cumulative culture. Here we propose an integrated theoretical account of how the unique demands of acquiring instrumental skills and cultural conventions provide insight into when children imitate, when they innovate, and to what degree. For instrumental learning, with an increase in experience, high fidelity imitation decreases and innovation increases. By contrast, for conventional learning, imitative fidelity stays high, regardless of experience, and innovation stays low. We synthesize cutting edge research on the development of imitative flexibility and innovation to provide insight into the social learning mechanisms underpinning the uniquely human mind.

  16. Computational engineering

    CERN Document Server

    2014-01-01

    The book presents state-of-the-art works in computational engineering. Focus is on mathematical modeling, numerical simulation, experimental validation and visualization in engineering sciences. In particular, the following topics are presented: constitutive models and their implementation into finite element codes, numerical models in nonlinear elasto-dynamics including seismic excitations, multiphase models in structural engineering and multiscale models of materials systems, sensitivity and reliability analysis of engineering structures, the application of scientific computing in urban water management and hydraulic engineering, and the application of genetic algorithms for the registration of laser scanner point clouds.

  17. A new three-dimensional electromechanical impedance model for an embedded dual-PZT transducer

    Science.gov (United States)

    Wang, Dansheng; Li, Zhi; Zhu, Hongping

    2016-07-01

    In the past twenty years, the electromechanical (EM) impedance technique has been investigated extensively in the mechanical, aviation and civil engineering fields. Many different EM impedance models have been proposed to characterize the interaction between the surface-bonded PZT transducer and the host structure. This paper formulates a new three-dimensional EM impedance model characterizing the interaction between an embedded circle dual-PZT transducer and the host structure based on the effective impedance concept. The proposed model is validated by experimental results from a group of smart cement cubes, in which three circle dual-PZT transducers are embedded respectively. In addition, a new EM impedance measuring method for the dual-PZT transducer is also introduced. In the measuring method, only a common signal generator and an oscilloscope are needed, by which the exciting and receiving voltage signals are obtained respectively. Combined with fast Fourier transform the EM impedance signatures of the dual-PZT transducers are obtained.

  18. Thoracic applications of dual energy.

    Science.gov (United States)

    Remy-Jardin, Martine; Faivre, Jean-Baptiste; Pontana, Francois; Hachulla, Anne-Lise; Tacelli, Nunzia; Santangelo, Teresa; Remy, Jacques

    2010-01-01

    Recent technological advances in multidetector computed tomography (CT) have led to the introduction of dual-source CT, which allows acquisition of CT data at the same energy or at 2 distinct tube voltage settings during a single acquisition. The advantage of the former is improvement of temporal resolution, whereas the latter offers new options for CT imaging, allowing tissue characterization and functional analysis with morphologic evaluation. The most investigated application has been iodine mapping at pulmonary CT angiography. The material decomposition achievable opens up new options for recognizing substances poorly characterized by single-energy CT. Although it is too early to draw definitive conclusions on dual-energy CT applications, this article reviews the results already reported with the first generation of dual-source CT systems.

  19. Towards a big crunch dual

    Energy Technology Data Exchange (ETDEWEB)

    Hertog, Thomas E-mail: hertog@vulcan2.physics.ucsb.edu; Horowitz, Gary T

    2004-07-01

    We show there exist smooth asymptotically anti-de Sitter initial data which evolve to a big crunch singularity in a low energy supergravity limit of string theory. This opens up the possibility of using the dual conformal field theory to obtain a fully quantum description of the cosmological singularity. A preliminary study of this dual theory suggests that the big crunch is an endpoint of evolution even in the full string theory. We also show that any theory with scalar solitons must have negative energy solutions. The results presented here clarify our earlier work on cosmic censorship violation in N=8 supergravity. (author)

  20. DUAL BAND MONOPOLE ANTENNA DESIGN

    Directory of Open Access Journals (Sweden)

    P. Jithu

    2013-06-01

    Full Text Available The WLAN and Bluetooth applications become popular in mobile devices, integrating GSM and ISM bands operation in one compact antenna, can reduce the size of mobile devices. Recently, lot many investigations are carried out in designing a dual band antennas with operating frequencies in GSM band and in ISM band for mobile devices. Printed monopoles are under this investigation. In this paper, dual-band printed monopoles are presented to operate at GSM band i.e. 900 MHz and ISM band i.e. 2.4 GHz. We intend to observe the antenna characteristics on the network analyzer and verify the theoretical results with the practical ones.

  1. DESIGN OF A DUAL KEYBOARD

    Directory of Open Access Journals (Sweden)

    V. Ragavi

    2013-01-01

    Full Text Available The design of a computer keyboard with dual function is proposed. This computer keyboard called Dual Keyboard can function both as a normal keyboard and as a pressure sensitive keyboard. The proposed device has a switch that decides the function. The keyboard makes use of sensors placed beneath the keys to measure the pressure applied on the key by the user. This device has many applications. In this study, it is applied to mitigate Denial of Service (DoS attack.

  2. Nuclearity for Dual Operator Spaces

    Indian Academy of Sciences (India)

    Zhe Dong; Jicheng Tao

    2010-02-01

    In this short paper, we study the nuclearity for the dual operator space $V^∗$ of an operator space . We show that $V^∗$ is nuclear if and only if $V^{∗∗∗}$ is injective, where $V^{∗∗∗}$ is the third dual of . This is in striking contrast to the situation for general operator spaces. This result is used to prove that $V^{∗∗}$ is nuclear if and only if is nuclear and $V^{∗∗}$ is exact.

  3. Study of Effect of Diesel Fuel Energy Rate in Duel Fuel on Performance of Compression Ignition Engine

    OpenAIRE

    Maan Janan Basheer

    2012-01-01

    The aim of this work is to study the effect of diesel fuel percentage on the combustion processes in compression ignition engine using dual fuel (diesel and LPG). The brake thermal efficiency increased with the increase of diesel fuel rate at low loads, and decreased when load increased. To get sufficient operation in engine fueled with dual fuel, it required sufficient flow rate of diesel fuel, if the engine fueled with insufficient diesel fuel erratic operation with miss fire cycles presen...

  4. New tractors with dual-clutch transmission; Neue Traktoren mit Doppelkupplungsgetriebe

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, Andreas

    2012-04-15

    John Deere unveiled its new 6R series of tractors at Agritechnica 2011. The tractors will be offered in the course of 2012 with a dual-clutch transmission. Further innovations include a higher engine output and a higher lifting capacity. (orig.)

  5. CARDIOVASCULAR ENDOCRINOLOGY Dual RAAS blockade has dual effects on outcome

    NARCIS (Netherlands)

    Heerspink, Hiddo J. Lambers; de Zeeuw, Dick

    Makani and colleagues report that dual blockade of the renin-angiotensin-aldosterone system is associated with harm despite previous studies showing that this approach decreases blood pressure and albuminuria. Do these results imply that we should abandon surrogate markers? Or should we become more

  6. Dual-band dual-polarized array for WLAN applications

    CSIR Research Space (South Africa)

    Steyn, JM

    2009-01-01

    Full Text Available ) simultaneously. The two linear polarizations have separate ports. The presented design is characterized by dual-band operation, reasonably good front-to-back ratios, average gains of 5.2 dBi and 6.2 dBi over the 2.4 and 5.2 GHz bands respectively, stable end...

  7. Dual active surface heat flux gage probe

    Science.gov (United States)

    Liebert, Curt H.; Kolodziej, Paul

    1995-02-01

    A unique plug-type heat flux gage probe was tested in the NASA Ames Research Center 2x9 turbulent flow duct facility. The probe was fabricated by welding a miniature dual active surface heat flux gage body to the end of a hollow metal cylindrical bolt containing a metal inner tube. Cooling air flows through the inner tube, impinges onto the back of the gage body and then flows out through the annulus formed between the inner tube and the hollow bolt wall. Heat flux was generated in the duct facility with a Huels arc heater. The duct had a rectangular cross section and one wall was fabricated from 2.54 centimeter thick thermal insulation rigid surface material mounted onto an aluminum plate. To measure heat flux, the probe was inserted through the plate and insulating materials with the from of the gage located flush with the hot gas-side insulation surface. Absorbed heat fluxes measured with the probe were compared with absorbed heat fluxes measured with six water-cooled reference calorimeters. These calorimeters were located in a water-cooled metal duct wall which was located across from the probe position. Correspondence of transient and steady heat fluxes measured with the reference calorimeters and heat flux gage probe was generally within a satisfactory plus or minus 10 percent. This good correspondence was achieved even though the much cooler probe caused a large surface temperature disruption of 1000K between the metal gage and the insulation. However, this temperature disruption did not seriously effect the accuracy of the heat flux measurement. A current application for dual active surface heat flux gages is for transient and steady absorbed heat flux, surface temperature and heat transfer coefficient measurements on the surface of an oxidizer turbine inlet deflector operating in a space shuttle test bed engine.

  8. Status of the Combined Cycle Engine Rig

    Science.gov (United States)

    Saunders, Dave; Slater, John; Dippold, Vance

    2009-01-01

    Status for the past year is provided of the turbine-based Combined-Cycle Engine (CCE) Rig for the hypersonic project. As part of the first stage propulsion of a two-stage-to-orbit vehicle concept, this engine rig is designed with a common inlet that supplies flow to a turbine engine and a dual-mode ramjet / scramjet engine in an over/under configuration. At Mach 4 the inlet has variable geometry to switch the airflow from the turbine to the ramjet / scramjet engine. This process is known as inlet mode-transition. In addition to investigating inlet aspects of mode transition, the rig will allow testing of turbine and scramjet systems later in the test series. Fully closing the splitter cowl "cocoons" the turbine engine and increases airflow to the scramjet duct. The CCE Rig will be a testbed to investigate integrated propulsion system and controls technology objectives. Four phases of testing are planned to 1) characterize the dual inlet database, 2) collect inlet dynamics using system identification techniques, 3) implement an inlet control to demonstrate mode-transition scenarios and 4) demonstrate integrated inlet/turbine engine operation through mode-transition. Status of the test planning and preparation activities is summarized with background on the inlet design and small-scale testing, analytical CFD predictions and some details of the large-scale hardware. The final stages of fabrication are underway.

  9. A dual method for maximum entropy restoration

    Science.gov (United States)

    Smith, C. B.

    1979-01-01

    A simple iterative dual algorithm for maximum entropy image restoration is presented. The dual algorithm involves fewer parameters than conventional minimization in the image space. Minicomputer test results for Fourier synthesis with inadequate phantom data are given.

  10. Sparsity and spectral properties of dual frames

    CERN Document Server

    Krahmer, Felix; Lemvig, Jakob

    2012-01-01

    We study sparsity and spectral properties of dual frames of a given finite frame. We show that any finite frame has a dual with no more than $n^2$ non-vanishing entries, where $n$ denotes the ambient dimension, and that for most frames no sparser dual is possible. Moreover, we derive an expression for the exact sparsity level of the sparsest dual for any given finite frame using a generalized notion of spark. We then study the spectral properties of dual frames in terms of singular values of the synthesis operator. We provide a complete characterization for which spectral patterns of dual frames are possible for a fixed frame. For many cases, we provide simple explicit constructions for dual frames with a given spectrum, in particular, if the constraint on the dual is that it be tight.

  11. Dual-Doppler Feasibility Study

    Science.gov (United States)

    Huddleston, Lisa L.

    2012-01-01

    When two or more Doppler weather radar systems are monitoring the same region, the Doppler velocities can be combined to form a three-dimensional (3-D) wind vector field thus providing for a more intuitive analysis of the wind field. A real-time display of the 3-D winds can assist forecasters in predicting the onset of convection and severe weather. The data can also be used to initialize local numerical weather prediction models. Two operational Doppler Radar systems are in the vicinity of Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS); these systems are operated by the 45th Space Wing (45 SW) and the National Weather Service Melbourne, Fla. (NWS MLB). Dual-Doppler applications were considered by the 45 SW in choosing the site for the new radar. Accordingly, the 45th Weather Squadron (45 WS), NWS MLB and the National Aeronautics and Space Administration tasked the Applied Meteorology Unit (AMU) to investigate the feasibility of establishing dual-Doppler capability using the two existing systems. This study investigated technical, hardware, and software requirements necessary to enable the establishment of a dual-Doppler capability. Review of the available literature pertaining to the dual-Doppler technique and consultation with experts revealed that the physical locations and resulting beam crossing angles of the 45 SW and NWS MLB radars make them ideally suited for a dual-Doppler capability. The dual-Doppler equations were derived to facilitate complete understanding of dual-Doppler synthesis; to determine the technical information requirements; and to determine the components of wind velocity from the equation of continuity and radial velocity data collected by the two Doppler radars. Analysis confirmed the suitability of the existing systems to provide the desired capability. In addition, it is possible that both 45 SW radar data and Terminal Doppler Weather Radar data from Orlando International Airport could be used to alleviate any

  12. Information Technology and the Dual-Degree Program

    Science.gov (United States)

    Kalia, Rajiv K.

    2000-03-01

    In recent years, a number of universities have made sweeping changes in science and engineering education at the graduate level by creating new and innovative curricula interfacing the physical, biological, and computer sciences, along with various engineering disciplines. The primary goal of these educational programs is to train a new generation of researchers who are capable of solving challenging science and engineering problems using parallel computers, high-speed networks, and advanced scientific visualization. LSU has established a dual-degree program that allows students to obtain a Ph.D. in the physical sciences and a M.S. from the Department of Computer Science. In support of this educational program, a multidisciplinary high performance computing and communications curriculum has been introduced, and a parallel-computing and three-dimensional, immersive and interactive visualization environment has been created. Dual-degree students also have extensive opportunities to do internships with scientists at government laboratories, universities, and industry in the US, Europe, and Japan.

  13. The next generation rocket engines

    Science.gov (United States)

    Beichel, Rudi; O'Brien, Charles J.; Taylor, James P.

    This paper examines propulsion system technologies for earth-to-orbit vehicles, and describes several propulsion system concepts which could support the recommendations of the Commission for Space Development for the year 2000. The hallmark of that system must and will be reliability. Reliability will be obtained through a very structured design approach, coupled with a rational, cost effective, development and qualification program. To improve the next generation space transportation propulsion systems we need to select the very best of alternative power and performance cycles and engine physical concepts with a rigid requirement to achieve a robust, dependable, affordable propulsion system. For example, engine concepts using either propellants or non-propellant fluids for cooling and/or power drive offer the potential to provide smooth, controlled engine starts, low turbine temperatures, etc. as required for long life turbomachinery. Concepts examined are LOX/LH 2, |LOX/LH 2 + hydrocarbon, and LOX/LH 2 + hydrocarbon + Al dual expander engines, separate LOX/LH 2 and LOX/hydrocarbon engines, and variable mixture ratio engines. A fully reusable propulsion system that is perceived to be very low risk and low in operation cost is described.

  14. Dual symmetry in a generalized Maxwell theory

    CERN Document Server

    Brandt, F T; McKeon, D G C

    2016-01-01

    We examine Podolsky's electrodynamics, which is noninvariant under the usual duality transformation. We deduce a generalization of Hodge's star duality, which leads to a dual gauge field and restores to a certain extent the dual symmetry. The model becomes fully dual symmetric asymptotically when it reduces to the Maxwell theory. We argue that this strict dual symmetry directly implies the existence of the basic invariants of the electromagnetic fields.

  15. Dual of QCD with One Adjoint Fermion

    CERN Document Server

    Mojaza, Matin; Pica, Claudio; Sannino, Francesco

    2011-01-01

    We construct the magnetic dual of QCD with one adjoint Weyl fermion. The dual is a consistent solution of the 't Hooft anomaly matching conditions, allows for flavor decoupling and remarkably constitutes the first nonsupersymmetric dual valid for any number of colors. The dual allows to bound the anomalous dimension of the Dirac fermion mass operator to be less than one in the conformal window.

  16. High Specific Power Multiple-Cylinder Alpha Free-Piston Stirling Engine Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed effort will result in a design of a 30 kWe dual opposed alpha free-piston Stirling engine power conversion system for space applications, and provide...

  17. Invisible Engineers

    Science.gov (United States)

    Ohashi, Hideo

    Questionnaire to ask “mention three names of scientists you know” and “three names of engineers you know” was conducted and the answers from 140 adults were analyzed. The results indicated that the image of scientists is represented by Nobel laureates and that of engineers by great inventors like Thomas Edison and industry founders like Soichiro Honda. In order to reveal the image of engineers among young generation, questionnaire was conducted for pupils in middle and high schools. Answers from 1,230 pupils were analyzed and 226 names mentioned as engineers were classified. White votes reached 60%. Engineers who are neither big inventors nor company founders collected less than 1% of named votes. Engineers are astonishingly invisible from young generation. Countermeasures are proposed.

  18. Engineering mechanics

    CERN Document Server

    Gross, Dietmar; Schröder, Jörg; Wall, Wolfgang A; Rajapakse, Nimal

    Statics is the first volume of a three-volume textbook on Engineering Mechanics. The authors, using a time-honoured straightforward and flexible approach, present the basic concepts and principles of mechanics in the clearest and simplest form possible to advanced undergraduate engineering students of various disciplines and different educational backgrounds. An important objective of this book is to develop problem solving skills in a systematic manner. Another aim of this volume is to provide engineering students as well as practising engineers with a solid foundation to help them bridge the gap between undergraduate studies on the one hand and advanced courses on mechanics and/or practical engineering problems on the other. The book contains numerous examples, along with their complete solutions. Emphasis is placed upon student participation in problem solving. The contents of the book correspond to the topics normally covered in courses on basic engineering mechanics at universities and colleges. Now in i...

  19. Dual Enrollment for High School Students

    Science.gov (United States)

    Edwards, Linsey; Hughes, Katherine

    2011-01-01

    Dual enrollment programs allow high school students to enroll in college courses and potentially earn college credit. The term concurrent enrollment is sometimes used interchangeably with dual enrollment, and sometimes to refer to a particular model of dual enrollment. In some programs, students earn high school and college credit simultaneously;…

  20. Dual Enrollment in Spanish: One Working Model

    Science.gov (United States)

    Bloom, Melanie; Chambers, Laura

    2009-01-01

    Dual enrollment is now a nation-wide phenomenon as all 50 states currently offer some form of dual-enrollment program to secondary-school students (Karp, Bailey, Hughes, and Fermin 2005). However, dual enrollment itself is often difficult to define as programs vary from school to school (Jordan, Cavalluzzo, and Corallo 2006). Therefore, language…

  1. Sparsity and spectral properties of dual frames

    DEFF Research Database (Denmark)

    Krahmer, Felix; Kutyniok, Gitta; Lemvig, Jakob

    2013-01-01

    We study sparsity and spectral properties of dual frames of a given finite frame. We show that any finite frame has a dual with no more than $n^2$ non-vanishing entries, where $n$ denotes the ambient dimension, and that for most frames no sparser dual is possible. Moreover, we derive an expressio...

  2. Dual Enrollment in Spanish: One Working Model

    Science.gov (United States)

    Bloom, Melanie; Chambers, Laura

    2009-01-01

    Dual enrollment is now a nation-wide phenomenon as all 50 states currently offer some form of dual-enrollment program to secondary-school students (Karp, Bailey, Hughes, and Fermin 2005). However, dual enrollment itself is often difficult to define as programs vary from school to school (Jordan, Cavalluzzo, and Corallo 2006). Therefore, language…

  3. Dual Space Technology Transfer

    Science.gov (United States)

    Kowbel, W.; Loutfy, R.

    2009-03-01

    Over the past fifteen years, MER has had several NASA SBIR Phase II programs in the area of space technology, based upon carbon-carbon (C-C) composites. In addition, in November 2004, leading edges supplied by MER provided the enabling technology to reach a Mach 10 record for an air breathing engine on the X-43 A flight. The MER business model constitutes a spin-off of technologies initially by incubating in house, and ultimately creating spin-off stand alone companies. FMC was formed to provide for technology transfer in the area of fabrication of C-C composites. FMC has acquired ISO 9000 and AS9100 quality certifications. FMC is fabricating under AS9100 certification, flight parts for several flight programs. In addition, FMC is expanding the application of carbon-carbon composites to several critical military programs. In addition to space technology transfer to critical military programs, FMC is becoming the world leader in the commercial area of low-cost C-C composites for furnace fixtures. Market penetrations have been accomplished in North America, Europe and Asia. Low-cost, quick turn-around and excellent quality of FMC products paves the way to greatly increased sales. In addition, FMC is actively pursuing a joint venture with a new partner, near closure, to become the leading supplier of high temperature carbon based composites. In addition, several other spin-off companies such as TMC, FiC, Li-Tech and NMIC were formed by MER with a plethora of potential space applications.

  4. Pairs of dual periodic frames

    DEFF Research Database (Denmark)

    Christensen, Ole; Goh, Say Song

    2012-01-01

    is needed. The purpose of the present paper is to provide constructions of dual pairs of frames in the setting of the Hilbert space of periodic functions L2(0,2π). The frames constructed are given explicitly as trigonometric polynomials, which allows for an efficient calculation of the coefficients...

  5. Noncommutative Self-dual Gravity

    CERN Document Server

    García-Compéan, H; Ramírez, C; Sabido, M

    2003-01-01

    Starting from a self-dual formulation of gravity, we obtain a noncommutative theory of pure Einstein theory in four dimensions. In order to do that, we use Seiberg-Witten map. It is shown that the noncommutative torsion constraint is solved by the vanishing of commutative torsion. Finally, the noncommutative corrections to the action are computed up to second order.

  6. Design of dual pressure regulator

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Soo; Kim, Kang Dae; Kim, Myoung Sub [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)

    2008-07-01

    In this paper, we designed sandwich type pressure regulator for air pressure control system. As a result of research, we obtained several important conclusions. First, we decided theory of poppet valve and relief valve which are used in sandwich type pressure regulator, and then designed prototype of pressure regulator. Second, we organized circuit diagram of dual pressure regulator of air pressure control system.

  7. Dual Processing and Diagnostic Errors

    Science.gov (United States)

    Norman, Geoff

    2009-01-01

    In this paper, I review evidence from two theories in psychology relevant to diagnosis and diagnostic errors. "Dual Process" theories of thinking, frequently mentioned with respect to diagnostic error, propose that categorization decisions can be made with either a fast, unconscious, contextual process called System 1 or a slow, analytical,…

  8. Physical Health and Dual Diagnosis

    OpenAIRE

    Robson, Debbie; Keen, Sarah; Mauro, Pia

    2008-01-01

    The physical health of people with mental illness may be neglected for a variety of reasons. This paper looks at the common physical health problems experienced by people with a dual diagnosis of substance misuse and serious mental illness, and suggests ways of assessing and managing them.

  9. Software engineering

    CERN Document Server

    Sommerville, Ian

    2010-01-01

    The ninth edition of Software Engineering presents a broad perspective of software engineering, focusing on the processes and techniques fundamental to the creation of reliable, software systems. Increased coverage of agile methods and software reuse, along with coverage of 'traditional' plan-driven software engineering, gives readers the most up-to-date view of the field currently available. Practical case studies, a full set of easy-to-access supplements, and extensive web resources make teaching the course easier than ever.

  10. Information engineering

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, D.N.

    1997-02-01

    The Information Engineering thrust area develops information technology to support the programmatic needs of Lawrence Livermore National Laboratory`s Engineering Directorate. Progress in five programmatic areas are described in separate reports contained herein. These are entitled Three-dimensional Object Creation, Manipulation, and Transport, Zephyr:A Secure Internet-Based Process to Streamline Engineering Procurements, Subcarrier Multiplexing: Optical Network Demonstrations, Parallel Optical Interconnect Technology Demonstration, and Intelligent Automation Architecture.

  11. Engineering tribology

    CERN Document Server

    Stachowiak, Gwidon; Batchelor, A W; Batchelor, Andrew W

    2005-01-01

    As with the previous edition, the third edition of Engineering Tribology provides a thorough understanding of friction and wear using technologies such as lubrication and special materials. Tribology is a complex topic with its own terminology and specialized concepts, yet is vitally important throughout all engineering disciplines, including mechanical design, aerodynamics, fluid dynamics and biomedical engineering. This edition includes updated material on the hydrodynamic aspects of tribology as well as new advances in the field of biotribology, with a focus throughout on the engineering ap

  12. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>20142564Chen Mingxing(Beijing Research Institute of Survey and Design,China Hydropower Engineering Consulting Group Co.,Beijing 100024,China);Chen Baoguo Application of Drilling Deviation Correcting and Deflecting Techniques in Geological Exploration at Songta Hydropower Station(Exploration Engineering,ISSN1672-7428,CN11-5063/TD,

  13. Systems Engineering

    Science.gov (United States)

    Pellerano, Fernando

    2015-01-01

    This short course provides information on what systems engineering is and how the systems engineer guides requirements, interfaces with the discipline leads, and resolves technical issues. There are many system-wide issues that either impact or are impacted by the thermal subsystem. This course will introduce these issues and illustrate them with real life examples.

  14. Governing Engineering

    DEFF Research Database (Denmark)

    Buch, Anders

    2012-01-01

    of knowledge, belief and opinions in which engineering is immersed. Thus the overall objective is explorative. By investigating the language, practices and techniques by which engineering is governed the chapter sets out to point to the presumptions, stipulations and ‘limits’ of the dominant discourses...

  15. Biomedical Engineering

    CERN Document Server

    Suh, Sang C; Tanik, Murat M

    2011-01-01

    Biomedical Engineering: Health Care Systems, Technology and Techniques is an edited volume with contributions from world experts. It provides readers with unique contributions related to current research and future healthcare systems. Practitioners and researchers focused on computer science, bioinformatics, engineering and medicine will find this book a valuable reference.

  16. Corrosion Engineering.

    Science.gov (United States)

    White, Charles V.

    A description is provided for a Corrosion and Corrosion Control course offered in the Continuing Engineering Education Program at the General Motors Institute (GMI). GMI is a small cooperative engineering school of approximately 2,000 students who alternate between six-week periods of academic study and six weeks of related work experience in…

  17. Food Engineering

    NARCIS (Netherlands)

    Boom, R.M.; Janssen, A.E.M.

    2014-01-01

    Food engineering is a rapidly changing discipline. Traditionally, the main focus was on food preservation and stabilization, whereas trends now are on diversity, health, taste, and sustainable production. Next to a general introduction of the definition of food engineering, this article gives a

  18. Genetic Engineering

    Science.gov (United States)

    Phillips, John

    1973-01-01

    Presents a review of genetic engineering, in which the genotypes of plants and animals (including human genotypes) may be manipulated for the benefit of the human species. Discusses associated problems and solutions and provides an extensive bibliography of literature relating to genetic engineering. (JR)

  19. Two-stage earth-to-orbit vehicles with dual-fuel propulsion in the Orbiter

    Science.gov (United States)

    Martin, J. A.

    1982-01-01

    Earth-to-orbit vehicle studies of future replacements for the Space Shuttle are needed to guide technology development. Previous studies that have examined single-stage vehicles have shown advantages for dual-fuel propulsion. Previous two-stage system studies have assumed all-hydrogen fuel for the Orbiters. The present study examined dual-fuel Orbiters and found that the system dry mass could be reduced with this concept. The possibility of staging the booster at a staging velocity low enough to allow coast-back to the launch site is shown to be beneficial, particularly in combination with a dual-fuel Orbiter. An engine evaluation indicated the same ranking of engines as did a previous single-stage study. Propane and RP-1 fuels result in lower vehicle dry mass than methane, and staged-combustion engines are preferred over gas-generator engines. The sensitivity to the engine selection is less for two-stage systems than for single-stage systems.

  20. Emotional engineering

    CERN Document Server

    In an age of increasing complexity, diversification and change, customers expect services that cater to their needs and to their tastes. Emotional Engineering vol 2. describes how their expectations can be satisfied and managed throughout the product life cycle, if producers focus their attention more on emotion. Emotional engineering provides the means to integrate products to create a new social framework and develops services beyond product realization to create of value across a full lifetime.  14 chapters cover a wide range of topics that can be applied to product, process and industry development, with special attention paid to the increasing importance of sensing in the age of extensive and frequent changes, including: • Multisensory stimulation and user experience  • Physiological measurement • Tactile sensation • Emotional quality management • Mental model • Kansei engineering.   Emotional Engineering vol 2 builds on Dr Fukuda’s previous book, Emotional Engineering, and provides read...

  1. Engineering surveying

    CERN Document Server

    Schofield, W

    2001-01-01

    The aim of Engineering Surveying has always been to impart and develop a clear understanding of the basic topics of the subject. The author has fully revised the book to make it the most up-to-date and relevant textbook available on the subject.The book also contains the latest information on trigonometric levelling, total stations and one-person measuring systems. A new chapter on satellites ensures a firm grasp of this vitally important topic.The text covers engineering surveying modules for civil engineering students on degree courses and forms a reference for the engineering surveying module in land surveying courses. It will also prove to be a valuable reference for practitioners.* Simple clear introduction to surveying for engineers* Explains key techniques and methods* Details reading systems and satellite position fixing

  2. Architectural Engineers

    DEFF Research Database (Denmark)

    Petersen, Rikke Premer

    The design professions have always been an amorphous phenomena difficult to merge under one label. New constellations continually emerge, questioning, stretching, and reconfiguring the understanding of design and the professional practices linked to it. In this paper the idea of architectural...... engineering is addresses from two perspectives – as an educational response and an occupational constellation. Architecture and engineering are two of the traditional design professions and they frequently meet in the occupational setting, but at educational institutions they remain largely estranged....... The paper builds on a multi-sited study of an architectural engineering program at the Technical University of Denmark and an architectural engineering team within an international engineering consultancy based on Denmark. They are both responding to new tendencies within the building industry where...

  3. Dual leadership in a hospital practice

    DEFF Research Database (Denmark)

    Thude, Bettina Ravnborg; Thomsen, Svend Erik; Stenager, Egon

    2017-01-01

    in the hospital context and develops a categorizing tool for being able to distinguish dual leadership teams from each other. It is important to reveal if there are any indicators that can be used for optimising dual leadership teams in the health-care sector and in other organisations......., this study aims to analyse three different dual leadership pairs at a Danish hospital. Furthermore, this study develops a tool to characterize dual leadership teams from each other. Design/methodology/approach This is a qualitative study using semi-structured interviews. Six leaders were interviewed...... that power balance, personal relations and decision processes are important factors for creating efficient dual leaderships. The study develops a categorizing tool to use for further research or for organizations, to describe and analyse dual leaderships. Originality/value The study describes dual leadership...

  4. MECHANISM ON DISTRIBUTION OF PILOT FUEL SPRAY AND COMPRESSING IGNITION IN PREMIXED NATURAL GAS ENGINE IGNITED BY PILOT DIESEL

    Institute of Scientific and Technical Information of China (English)

    Yao Chunde; Yao Guangtao; Song Jinou; Wang Yinshan

    2005-01-01

    Numerical simulations of pilot fuel spray and compressing ignition for pre-mixed natural gas ignited by pilot diesel are described. By means of these modeling, the dual fuel and diesel fuel ignition mechanism of some phenomena investigated on an optional engine by technology of high-speed CCD is analyzed. It is demonstrated that the longer delay of ignition in dual fuel engine is not mainly caused by change of the mixture thermodynamics parameters. The analysis results illustrate that the ignition of pre-mixed natural gas ignited by pilot diesel taking place in dual fuel engine is a process of homogenous charge compression ignition.

  5. Optimized batteries for cars with dual electrical architecture

    Science.gov (United States)

    Douady, J. P.; Pascon, C.; Dugast, A.; Fossati, G.

    During recent years, the increase in car electrical equipment has led to many problems with traditional starter batteries (such as cranking failure due to flat batteries, battery cycling etc.). The main causes of these problems are the double function of the automotive battery (starter and service functions) and the difficulties in designing batteries well adapted to these two functions. In order to solve these problems a new concept — the dual-concept — has been developed with two separate batteries: one battery is dedicated to the starter function and the other is dedicated to the service function. Only one alternator charges the two batteries with a separation device between the two electrical circuits. The starter battery is located in the engine compartment while the service battery is located at the rear of the car. From the analysis of new requirements, battery designs have been optimized regarding the two types of functions: (i) a small battery with high specific power for the starting function; for this function a flooded battery with lead-calcium alloy grids and thin plates is proposed; (ii) for the service function, modified sealed gas-recombinant batteries with cycling and deep-discharge ability have been developed. The various advantages of the dual-concept are studied in terms of starting reliability, battery weight, and voltage supply. The operating conditions of the system and several dual electrical architectures have also been studied in the laboratory and the car. The feasibility of the concept is proved.

  6. Dual voltage power supply with 48 volt

    Energy Technology Data Exchange (ETDEWEB)

    Froeschl, Joachim; Proebstle, Hartmut; Sirch, Ottmar [BMW Group, Muenchen (Germany)

    2012-11-01

    Automotive electrics/electronics have just reached a period of tremendous change. High voltage systems for Hybrid, Plug-In Hybrid or Battery Electric Vehicles with high power electric motors, high energy accumulators and electric climate compressors will be introduced in order to achieve the challenging targets for CO{sub 2} emissions and energy efficiency and to anticipate the mobility of the future. Additionally, innovations and the continuous increase of functionality for comfort, safety, driver assistance and infotainment systems require more and more electrical power of the vehicle power supply at all. On the one hand side electrified vehicles will certainly achieve a significant market share, on the other hand side they will increase the pressure to conventional vehicles with combustion engines for fuel consumption and CO{sub 2} emissions. These vehicles will be enabled to keep their competitiveness by new functions and the optimization of their electric systems. A dual voltage power supply with 48 Volt and 12 Volt will be one of the key technologies to realize these requirements. The power capability of the existing 12 Volt power supply has reached its limits. Further potentials can only be admitted by the introduction of 48 Volt. For this reason the car manufacturers Audi, BMW, Daimler, Porsche and Volkswagen started very early on this item and developed a common specification of the new voltage range. Now, it is necessary to identify the probable systems at this voltage range and to start the developments. (orig.)

  7. Social network analysis and dual rover communications

    Science.gov (United States)

    Litaker, Harry L.; Howard, Robert L.

    2013-10-01

    Social network analysis (SNA) refers to the collection of techniques, tools, and methods used in sociometry aiming at the analysis of social networks to investigate decision making, group communication, and the distribution of information. Human factors engineers at the National Aeronautics and Space Administration (NASA) conducted a social network analysis on communication data collected during a 14-day field study operating a dual rover exploration mission to better understand the relationships between certain network groups such as ground control, flight teams, and planetary science. The analysis identified two communication network structures for the continuous communication and Twice-a-Day Communication scenarios as a split network and negotiated network respectfully. The major nodes or groups for the networks' architecture, transmittal status, and information were identified using graphical network mapping, quantitative analysis of subjective impressions, and quantified statistical analysis using Sociometric Statue and Centrality. Post-questionnaire analysis along with interviews revealed advantages and disadvantages of each network structure with team members identifying the need for a more stable continuous communication network, improved robustness of voice loops, and better systems training/capabilities for scientific imagery data and operational data during Twice-a-Day Communications.

  8. The dual role of coherent twin boundaries in hydrogen embrittlement.

    Science.gov (United States)

    Seita, Matteo; Hanson, John P; Gradečak, Silvija; Demkowicz, Michael J

    2015-02-05

    Hydrogen embrittlement (HE) causes engineering alloys to fracture unexpectedly, often at considerable economic or environmental cost. Inaccurate predictions of component lifetimes arise from inadequate understanding of how alloy microstructure affects HE. Here we investigate hydrogen-assisted fracture of a Ni-base superalloy and identify coherent twin boundaries (CTBs) as the microstructural features most susceptible to crack initiation. This is a surprising result considering the renowned beneficial effect of CTBs on mechanical strength and corrosion resistance of many engineering alloys. Remarkably, we also find that CTBs are resistant to crack propagation, implying that hydrogen-assisted crack initiation and propagation are governed by distinct physical mechanisms in Ni-base alloys. This finding motivates a re-evaluation of current lifetime models in light of the dual role of CTBs. It also indicates new paths to designing materials with HE-resistant microstructures.

  9. The dual role of coherent twin boundaries in hydrogen embrittlement

    Science.gov (United States)

    Seita, Matteo; Hanson, John P.; Gradečak, Silvija; Demkowicz, Michael J.

    2015-02-01

    Hydrogen embrittlement (HE) causes engineering alloys to fracture unexpectedly, often at considerable economic or environmental cost. Inaccurate predictions of component lifetimes arise from inadequate understanding of how alloy microstructure affects HE. Here we investigate hydrogen-assisted fracture of a Ni-base superalloy and identify coherent twin boundaries (CTBs) as the microstructural features most susceptible to crack initiation. This is a surprising result considering the renowned beneficial effect of CTBs on mechanical strength and corrosion resistance of many engineering alloys. Remarkably, we also find that CTBs are resistant to crack propagation, implying that hydrogen-assisted crack initiation and propagation are governed by distinct physical mechanisms in Ni-base alloys. This finding motivates a re-evaluation of current lifetime models in light of the dual role of CTBs. It also indicates new paths to designing materials with HE-resistant microstructures.

  10. Dual Mode Slotted Monopole Antenna

    Science.gov (United States)

    2017-01-05

    of 15 DUAL MODE SLOTTED MONOPOLE ANTENNA STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured and used by...REFERENCE TO OTHER PATENT APPLICATIONS [0002] None. BACKGROUND OF THE INVENTION (1) Field of the Invention [0003] The present invention is directed...such as this that is capable of radiating at a different frequency below this cutoff. The present invention provides a means by which the overall

  11. Dual geometries and spacetime singularities

    CERN Document Server

    Quirós, I

    2000-01-01

    The concept of geometrical duality is disscused in the context of Brans-Dicke theory and extended to general relativity. It is shown, in some generic cases, that spacetime singularities that arise in usual Riemannian general relativity, may be avoided in its dual representation: Weyl-like general relativity, thus providing a singularity-free picture of the World that is physicaly equivalent to the canonical general relativistic one.

  12. Dual arm master controller concept

    Energy Technology Data Exchange (ETDEWEB)

    Kuban, D.P.; Perkins, G.S.

    1984-01-01

    The Advanced Servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented. 6 references, 3 figures.

  13. Dual targeting of peroxisomal proteins

    Directory of Open Access Journals (Sweden)

    Julia eAst

    2013-10-01

    Full Text Available Cellular compartmentalization into organelles serves to separate biological processes within the environment of a single cell. While some metabolic reactions are specific to a single organelle, others occur in more than one cellular compartment. Specific targeting of proteins to compartments inside of eukaryotic cells is mediated by defined sequence motifs. To achieve multiple targeting to different compartments cells use a variety of strategies. Here, we focus on mechanisms leading to dual targeting of peroxisomal proteins. In many instances, isoforms of peroxisomal proteins with distinct intracellular localization are encoded by separate genes. But also single genes can give rise to differentially localized proteins. Different isoforms can be generated by use of alternative transcriptional start sites, by differential splicing or ribosomal read-through of stop codons. In all these cases different peptide variants are produced, of which only one carries a peroxisomal targeting signal. Alternatively, peroxisomal proteins contain additional signals that compete for intracellular targeting. Dual localization of proteins residing in both the cytoplasm and in peroxisomes may also result from use of inefficient targeting signals. The recent observation that some bona fide cytoplasmic enzymes were also found in peroxisomes indicates that dual targeting of proteins to both the cytoplasm and the peroxisome might be more widespread. Although current knowledge of proteins exhibiting only partial peroxisomal targeting is far from being complete, we speculate that the metabolic capacity of peroxisomes might be larger than previously assumed.

  14. Dual Fluidized Bed Biomass Gasification

    Energy Technology Data Exchange (ETDEWEB)

    None

    2005-09-30

    The dual fluidized bed reactor is a recirculating system in which one half of the unit operates as a steam pyrolysis device for biomass. The pyrolysis occurs by introducing biomass and steam to a hot fluidized bed of inert material such as coarse sand. Syngas is produced during the pyrolysis and exits the top of the reactor with the steam. A crossover arm, fed by gravity, moves sand and char from the pyrolyzer to the second fluidized bed. This sand bed uses blown air to combust the char. The exit stream from this side of the reactor is carbon dioxide, water and ash. There is a second gravity fed crossover arm to return sand to the pyrolysis side. The recirculating action of the sand and the char is the key to the operation of the dual fluidized bed reactor. The objective of the project was to design and construct a dual fluidized bed prototype reactor from literature information and in discussion with established experts in the field. That would be appropriate in scale and operation to measure the relative performance of the gasification of biomass and low ranked coals to produce a high quality synthesis gas with no dilution from nitrogen or combustion products.

  15. DUAL RECIPROCITY HYBRID BOUNDARY NODE METHOD FOR THREE-DIMENSIONAL ELASTICITY WITH BODY FORCE

    Institute of Scientific and Technical Information of China (English)

    Fei Yan; Yuanhan Wang; Yu Miao; Fei Tan

    2008-01-01

    Combining Dual Reciprocity Method (DRM) with Hybrid Bòundary Node Method(HBNM),the Dual Reciprocity Hybrid Boundary Node Method (DRHBNM) is developed for three-dimensional linear elasticity problems with body force.This method can be used to solve the elasticity problems with body force without domain integral,which is inevitable by HBNM.To demonstrate the versatility and the fast convergence of this method,some numerical examples of 3-D elasticity problems with body forces are examined.The computational results show that the present method is effective and can be widely applied in solving practical engineering problems.

  16. Engineering mathematics

    CERN Document Server

    Stroud, K A

    2013-01-01

    A groundbreaking and comprehensive reference that's been a bestseller since it first debuted in 1970, the new seventh edition of Engineering Mathematics has been thoroughly revised and expanded. Providing a broad mathematical survey, this innovative volume covers a full range of topics from the very basic to the advanced. Whether you're an engineer looking for a useful on-the-job reference or want to improve your mathematical skills, or you are a student who needs an in-depth self-study guide, Engineering Mathematics is sure to come in handy time and time again.

  17. Advancing the Limits of Dual Fuel Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Koenigsson, Fredrik

    2012-07-01

    There is a growing interest in alternative transport fuels. There are two underlying reasons for this interest; the desire to decrease the environmental impact of transports and the need to compensate for the declining availability of petroleum. In the light of both these factors the Diesel Dual Fuel, DDF, engine is an attractive concept. The primary fuel of the DDF engine is methane, which can be derived both from renewables and from fossil sources. Methane from organic waste; commonly referred to as biomethane, can provide a reduction in greenhouse gases unmatched by any other fuel. The DDF engine is from a combustion point of view a hybrid between the diesel and the otto engine and it shares characteristics with both. This work identifies the main challenges of DDF operation and suggests methods to overcome them. Injector tip temperature and pre-ignitions have been found to limit performance in addition to the restrictions known from literature such as knock and emissions of NO{sub x} and HC. HC emissions are especially challenging at light load where throttling is required to promote flame propagation. For this reason it is desired to increase the lean limit in the light load range in order to reduce pumping losses and increase efficiency. It is shown that the best results in this area are achieved by using early diesel injection to achieve HCCI/RCCI combustion where combustion phasing is controlled by the ratio between diesel and methane. However, even without committing to HCCI/RCCI combustion and the difficult control issues associated with it, substantial gains are accomplished by splitting the diesel injection into two and allocating most of the diesel fuel to the early injection. HCCI/RCCI and PPCI combustion can be used with great effect to reduce the emissions of unburned hydrocarbons at light load. At high load, the challenges that need to be overcome are mostly related to heat. Injector tip temperatures need to be observed since the cooling effect of

  18. Identifying HIV-1 dual infections

    Directory of Open Access Journals (Sweden)

    Cornelissen Marion

    2007-09-01

    Full Text Available Abstract Transmission of human immunodeficiency virus (HIV is no exception to the phenomenon that a second, productive infection with another strain of the same virus is feasible. Experiments with RNA viruses have suggested that both coinfections (simultaneous infection with two strains of a virus and superinfections (second infection after a specific immune response to the first infecting strain has developed can result in increased fitness of the viral population. Concerns about dual infections with HIV are increasing. First, the frequent detection of superinfections seems to indicate that it will be difficult to develop a prophylactic vaccine. Second, HIV-1 superinfections have been associated with accelerated disease progression, although this is not true for all persons. In fact, superinfections have even been detected in persons controlling their HIV infections without antiretroviral therapy. Third, dual infections can give rise to recombinant viruses, which are increasingly found in the HIV-1 epidemic. Recombinants could have increased fitness over the parental strains, as in vitro models suggest, and could exhibit increased pathogenicity. Multiple drug resistant (MDR strains could recombine to produce a pan-resistant, transmittable virus. We will describe in this review what is presently known about super- and re-infection among ambient viral infections, as well as the first cases of HIV-1 superinfection, including HIV-1 triple infections. The clinical implications, the impact of the immune system, and the effect of anti-retroviral therapy will be covered, as will as the timing of HIV superinfection. The methods used to detect HIV-1 dual infections will be discussed in detail. To increase the likelihood of detecting a dual HIV-1 infection, pre-selection of patients can be done by serotyping, heteroduplex mobility assays (HMA, counting the degenerate base codes in the HIV-1 genotyping sequence, or surveying unexpected increases in the

  19. Coastal Engineering

    NARCIS (Netherlands)

    Van der Velden, E.T.J.M.

    1989-01-01

    Introduction, waves, sediment transport, littoral transport, lonshore sediment transport, onshore-offshore sediment transport, coastal changes, dune erosion and storm surges, sedimentation in channels and trenches, coastal engineering in practice.

  20. Green Engineering

    Science.gov (United States)

    Green Engineering is the design, commercialization and use of processes and products that are feasible and economical while reducing the generation of pollution at the source and minimizing the risk to human health and the environment.

  1. Harmonic engine

    Science.gov (United States)

    Bennett, Charles L.

    2009-10-20

    A high efficiency harmonic engine based on a resonantly reciprocating piston expander that extracts work from heat and pressurizes working fluid in a reciprocating piston compressor. The engine preferably includes harmonic oscillator valves capable of oscillating at a resonant frequency for controlling the flow of working fluid into and out of the expander, and also preferably includes a shunt line connecting an expansion chamber of the expander to a buffer chamber of the expander for minimizing pressure variations in the fluidic circuit of the engine. The engine is especially designed to operate with very high temperature input to the expander and very low temperature input to the compressor, to produce very high thermal conversion efficiency.

  2. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20112760 Dai Guozhong (College of Civil Engineering,Changzhou Institute of Tech- nology,Changzhou 213002,China);Zhang Yaxing Study on Solid-Free Drilling Fluid of PVM Polymer and Its Application (Geology

  3. Engineering Geology.

    Science.gov (United States)

    Ivey, John B.

    1983-01-01

    Engineering geology activities in government and the private sector are highlighted. Also highlighted are conferences in this field, awards presented at conferences (including an award to an undergraduate geology student), and a new publication "Geotechnology in Massachusetts." (JN)

  4. Software engineering

    CERN Document Server

    Sommerville, Ian

    2016-01-01

    For courses in computer science and software engineering The Fundamental Practice of Software Engineering Software Engineering introduces readers to the overwhelmingly important subject of software programming and development. In the past few years, computer systems have come to dominate not just our technological growth, but the foundations of our world's major industries. This text seeks to lay out the fundamental concepts of this huge and continually growing subject area in a clear and comprehensive manner. The Tenth Edition contains new information that highlights various technological updates of recent years, providing readers with highly relevant and current information. Sommerville's experience in system dependability and systems engineering guides the text through a traditional plan-based approach that incorporates some novel agile methods. The text strives to teach the innovators of tomorrow how to create software that will make our world a better, safer, and more advanced place to live.

  5. Construction of chimeric dual-chain avidin by tandem fusion of the related avidins.

    Science.gov (United States)

    Riihimäki, Tiina A; Kukkurainen, Sampo; Varjonen, Suvi; Hörhä, Jarno; Nyholm, Thomas K M; Kulomaa, Markku S; Hytönen, Vesa P

    2011-01-01

    Avidin is a chicken egg-white protein with high affinity to vitamin H, also known as D-biotin. Many applications in life science research are based on this strong interaction. Avidin is a homotetrameric protein, which promotes its modification to symmetrical entities. Dual-chain avidin, a genetically engineered avidin form, has two circularly permuted chicken avidin monomers that are tandem-fused into one polypeptide chain. This form of avidin enables independent modification of the two domains, including the two biotin-binding pockets; however, decreased yields in protein production, compared to wt avidin, and complicated genetic manipulation of two highly similar DNA sequences in the tandem gene have limited the use of dual-chain avidin in biotechnological applications. To overcome challenges associated with the original dual-chain avidin, we developed chimeric dual-chain avidin, which is a tandem fusion of avidin and avidin-related protein 4 (AVR4), another member of the chicken avidin gene family. We observed an increase in protein production and better thermal stability, compared with the original dual-chain avidin. Additionally, PCR amplification of the hybrid gene was more efficient, thus enabling more convenient and straightforward modification of the dual-chain avidin. When studied closer, the generated chimeric dual-chain avidin showed biphasic biotin dissociation. The improved dual-chain avidin introduced here increases its potential for future applications. This molecule offers a valuable base for developing bi-functional avidin tools for bioseparation, carrier proteins, and nanoscale adapters. Additionally, this strategy could be helpful when generating hetero-oligomers from other oligomeric proteins with high structural similarity.

  6. Construction of chimeric dual-chain avidin by tandem fusion of the related avidins.

    Directory of Open Access Journals (Sweden)

    Tiina A Riihimäki

    Full Text Available BACKGROUND: Avidin is a chicken egg-white protein with high affinity to vitamin H, also known as D-biotin. Many applications in life science research are based on this strong interaction. Avidin is a homotetrameric protein, which promotes its modification to symmetrical entities. Dual-chain avidin, a genetically engineered avidin form, has two circularly permuted chicken avidin monomers that are tandem-fused into one polypeptide chain. This form of avidin enables independent modification of the two domains, including the two biotin-binding pockets; however, decreased yields in protein production, compared to wt avidin, and complicated genetic manipulation of two highly similar DNA sequences in the tandem gene have limited the use of dual-chain avidin in biotechnological applications. PRINCIPAL FINDINGS: To overcome challenges associated with the original dual-chain avidin, we developed chimeric dual-chain avidin, which is a tandem fusion of avidin and avidin-related protein 4 (AVR4, another member of the chicken avidin gene family. We observed an increase in protein production and better thermal stability, compared with the original dual-chain avidin. Additionally, PCR amplification of the hybrid gene was more efficient, thus enabling more convenient and straightforward modification of the dual-chain avidin. When studied closer, the generated chimeric dual-chain avidin showed biphasic biotin dissociation. SIGNIFICANCE: The improved dual-chain avidin introduced here increases its potential for future applications. This molecule offers a valuable base for developing bi-functional avidin tools for bioseparation, carrier proteins, and nanoscale adapters. Additionally, this strategy could be helpful when generating hetero-oligomers from other oligomeric proteins with high structural similarity.

  7. Rehabilitation Engineering: What is Rehabilitation Engineering?

    Science.gov (United States)

    ... Parents/Teachers Resource Links for Students Glossary Rehabilitation Engineering What is rehabilitation engineering? How can future rehabilitation ... the area of rehabilitation engineering? What is rehabilitation engineering? Powered prosthetic leg. Source : M. Goldfarb, Vanderbilt U. ...

  8. Microwave engineering

    CERN Document Server

    Pozar, David M

    2012-01-01

    The 4th edition of this classic text provides a thorough coverage of RF and microwave engineering concepts, starting from fundamental principles of electrical engineering, with applications to microwave circuits and devices of practical importance.  Coverage includes microwave network analysis, impedance matching, directional couplers and hybrids, microwave filters, ferrite devices, noise, nonlinear effects, and the design of microwave oscillators, amplifiers, and mixers. Material on microwave and RF systems includes wireless communications, radar, radiometry, and radiation hazards. A large

  9. Dual Headquarters Involvement in Subsidiary Innovation

    DEFF Research Database (Denmark)

    Dellestrand, Henrik; Kappen, Philip; Nell, Phillip Christopher

    2014-01-01

    innovation importance, i.e., an innovation that is important for the division and the corporate level, drives dual headquarters involvement in innovation development. Contrary to expectations, no significant effect of dual embeddedness on dual headquarters involvement is found. The network size......The strategy and international business literature has identified the overall potential for headquarters to add value by allocating resources to subsidiary activities, but little is known about the extent to which multiple headquarters simultaneously involves itself in subsidiary operations...

  10. Advanced high pressure engine study for mixed-mode vehicle applications

    Science.gov (United States)

    Luscher, W. P.; Mellish, J. A.

    1977-01-01

    High pressure liquid rocket engine design, performance, weight, envelope, and operational characteristics were evaluated for a variety of candidate engines for use in mixed-mode, single-stage-to-orbit applications. Propellant property and performance data were obtained for candidate Mode 1 fuels which included: RP-1, RJ-5, hydrazine, monomethyl-hydrazine, and methane. The common oxidizer was liquid oxygen. Oxygen, the candidate Mode 1 fuels, and hydrogen were evaluated as thrust chamber coolants. Oxygen, methane, and hydrogen were found to be the most viable cooling candidates. Water, lithium, and sodium-potassium were also evaluated as auxiliary coolant systems. Water proved to be the best of these, but the system was heavier than those systems which cooled with the engine propellants. Engine weight and envelope parametric data were established for candidate Mode 1, Mode 2, and dual-fuel engines. Delivered engine performance data were also calculated for all candidate Mode 1 and dual-fuel engines.

  11. Running at Double Pace: Women in Dual-Profession Marriages.

    Science.gov (United States)

    Arfken, Deborah Elwell

    Although the problems facing dual-profession couples are almost universally acknowledged, studies on dual-profession couples have only recently emerged from those on dual-worker or dual-career families. To explore the perceptions that women in dual-profession marriages have of their roles, conflicts, and coping strategies, focus group interviews…

  12. Direct Initiation Through Detonation Branching in a Pulsed Detonation Engine

    Science.gov (United States)

    2008-03-01

    Detonation Engine The core of the PDE used in this research is a General Motors (GM) Quad 4 engine head with dual overhead camshafts . The head...manifold injection lines labeled The conventional poppet style valves are mechanically actuated by their respective camshafts which are in turn driven by...the angular position of the camshaft which is then used by the control computer to determine valve position and subsequent firing times. Depending

  13. Dual Language Learning / Duale Spracherlernung. Learning German through English

    Directory of Open Access Journals (Sweden)

    Fee-Alexandra Haase

    2014-07-01

    Full Text Available In this article we examine the impact of English in the learning process of the German language exemplified with the example of the second language acquisition process of the German language in the programs of German in the Department of Foreign Languages of the University of Nizwa in Oman. This study focuses on the distinct features of students in Oman learning German as a second language in an institution of higher education in Oman. The contrastive rhetoric of a German – Oman Arabic language contact situation is challenging and a unique field of research, which allows us to study the process of foreign language learning (L2 and the implementation of the culture of the native language L1 (Arabic. The reflection of the L1 culture, the Arab Oman culture, in the language learning process of the L2 language (German will be described, analyzed and discussed aiming the improvement of the L2 learning process. This article investigates into the process of learning German in an Arabic country of native speakers of Arabic from the perspective of the cultural differences of both cultures in terms of their linguistic prepositions.Received: 17/09/2013 / Accepted: 23/11/2013How to reference this articleHaase, F-A. (2014. Dual Language Learning / Duale Spracherlernung. Learning German through English. Foro de Educación, 12(17, pp. 197-216. doi: http://dx.doi.org/10.14516/fde.2014.012.017.010

  14. Natural gas in a D. I. diesel engine. A comparison of two different ways. [Direct injection diesel enginer

    Energy Technology Data Exchange (ETDEWEB)

    Jun-ming, Qu; Sorenson, S.C.; Kofoed, E.

    1987-01-01

    A D.I. diesel engine was modified for natural gas operation with pilot injection and with spark ignition so that a comparative analysis of these two different ways of using natural gas could be made. The results of the experiments indicate that for a diesel engine, it is possible that the operating characteristics of a straight natural gas engine are comparable with those of a diesel/gas engine at the same compression ratio and speed. For a dual fuel engine with pilot injection the best diesel/gas ratio by energy content is approximately 20/80 at full load operation. For straight natural gas engine with spark ignition, quality governed natural gas operation has good efficiency but poor NOx emissions. This problem could be improved through throttle controlled operation. These two different ways of using natural gas are best suited to stationary engines.

  15. The Dual Language Program Planner: A Guide for Designing and Implementing Dual Language Programs.

    Science.gov (United States)

    Howard, Elizabeth R.; Olague, Natalie; Rogers, David

    This guide offers a framework to facilitate the planning process for dual language programs, assuming at least a basic working knowledge of the central characteristics and essential features of dual language models. It provides an overview of the various models that serve linguistically diverse student populations, defining the term dual language…

  16. Dual arm master controller development

    Energy Technology Data Exchange (ETDEWEB)

    Kuban, D.P.; Perkins, G.S.

    1985-01-01

    The advanced servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented. This work was performed as part of the Consolidated Fuel Reprocessing Program at the Oak Ridge National Laboratory. 5 refs., 7 figs., 1 tab.

  17. Intent of Study on the Use of a Dual Airborne Laser Scanner (ALS) in Conjunction with a Tactical Grade Inertial Measurement Unit (IMU) for Unmanned Aerial Vehicle (UAV) Navigation and Mapping in Unknown, Non-Global Positioning System (GPS), Environments

    Science.gov (United States)

    2006-08-05

    Zofia Starzyk a. REPORT UNCLASSIFIED b. ABSTRACT UNCLASSIFIED c. THIS PAGE UNCLASSIFIED UL 19 19b. TELEPHONE NUMBER (include area code ...Navigation ( SITAN ) [2][3]. 5 Ohio University Avionics Engineering Center In the 1990s, the complementary nature of GPS to an IMU was quickly realized...ft AGL 14 Ohio University Avionics Engineering Center IV. DUAL ALS SIMULATION Software for the Dual ALS algorithm was written in MATLAB ™ and

  18. Engineering Optics

    CERN Document Server

    Iizuka, Keigo

    2008-01-01

    Engineering Optics is a book for students who want to apply their knowledge of optics to engineering problems, as well as for engineering students who want to acquire the basic principles of optics. It covers such important topics as optical signal processing, holography, tomography, holographic radars, fiber optical communication, electro- and acousto-optic devices, and integrated optics (including optical bistability). As a basis for understanding these topics, the first few chapters give easy-to-follow explanations of diffraction theory, Fourier transforms, and geometrical optics. Practical examples, such as the video disk, the Fresnel zone plate, and many more, appear throughout the text, together with numerous solved exercises. There is an entirely new section in this updated edition on 3-D imaging.

  19. Engineering physics

    CERN Document Server

    Mukherji, Uma

    2015-01-01

    ENGINEERING PHYSICS is designed as a textbook for first year engineering students of a two semester course in Applied Physics according to new revised syllabus. However the scope of this book is not only limited to undergraduate engineering students and science students, it can also serve as a reference book for practicing scientists.Advanced technological topics like LCD, Squid, Maglev system, Electron microscopes, MRI, Photonics - Photonic fibre, Nano-particles, CNT, Quantum computing etc., are explained with basic underlying principles of Physics.This text explained following topics with numerous solved, unsolved problems and questions from different angles. Part-I contains crystal structure, Liquid crystal, Thermo-electric effect, Thermionic emission, Ultrasonic, Acoustics, semiconductor and magnetic materials. Whereas Part-2 contains Optics, X-rays, Electron optics, Dielectric materials, Quantum Physics and Schrodinger wave equation, Laser, Fibre-optics and Holography, Radio-activity, Super-conductivity,...

  20. Engineering surveying

    CERN Document Server

    Schofield, W

    2007-01-01

    Engineering surveying involves determining the position of natural and man-made features on or beneath the Earth's surface and utilizing these features in the planning, design and construction of works. It is a critical part of any engineering project. Without an accurate understanding of the size, shape and nature of the site the project risks expensive and time-consuming errors or even catastrophic failure.Engineering Surveying 6th edition covers all the basic principles and practice of this complex subject and the authors bring expertise and clarity. Previous editions of this classic text have given readers a clear understanding of fundamentals such as vertical control, distance, angles and position right through to the most modern technologies, and this fully updated edition continues that tradition.This sixth edition includes:* An introduction to geodesy to facilitate greater understanding of satellite systems* A fully updated chapter on GPS, GLONASS and GALILEO for satellite positioning in surveying* Al...

  1. ENGINEERING GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20091943 Cao Zubao(Xi’an Branch of China Coal Research Institute,Xi’an 710054,China);Zhu Mingcheng Application of Pipe-Roof Curtain Grouting in Construction of Coal Mine Tunnel Crossing the Fractured Zone(Exploration Engineering,ISSN1672-7428,CN11-5063/TD,35(8),2008,p.79-81,3 illus.,4 refs.,with English abstract)Key words:curtain grouting20091944 Chen Changfu(Civil Engineering College,Hunan University,Changsha 410082,China);Xiao Shujun Application of Weighted Residual Method in Whole Internal Force Calculation of Anti-Slide Pile(Hydrogeology and Engineering Geology,ISSN1000-3665,CN11-2202/P,35(4),2008,p.75-79,3 illus.,9 refs.)Key words:slide-resistant

  2. Connecting NASA science and engineering with earth science applications

    Science.gov (United States)

    The National Research Council (NRC) recently highlighted the dual role of NASA to support both science and applications in planning Earth observations. This Editorial reports the efforts of the NASA Soil Moisture Active Passive (SMAP) mission to integrate applications with science and engineering i...

  3. 77 FR 10950 - Airworthiness Directives; General Electric Company (GE) Turbofan Engines

    Science.gov (United States)

    2012-02-24

    ...-channel central processing unit (CPU) faults in the ECU, and four reports of engine flameout ground events... caused by dual-channel central processing unit (CPU) faults in the electronic control unit (ECU); and (3... unit (ECU), which increases the engine's margin to flameout. This new AD requires the removal of the...

  4. Micro Engineering

    DEFF Research Database (Denmark)

    Alting, Leo; Kimura, F.; Hansen, Hans Nørgaard

    2003-01-01

    The paper addresses the questions of how micro products are designed and how they are manufactured. Definitions of micro products and micro engineering are discussed and the presentation is aimed at describing typical issues, possibilities and tools regarding design of micro products. The implica......The paper addresses the questions of how micro products are designed and how they are manufactured. Definitions of micro products and micro engineering are discussed and the presentation is aimed at describing typical issues, possibilities and tools regarding design of micro products...

  5. ENGINEERING GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>20140498An Shize(Sichuan Institute of Geological Engineering Investigation,Chengdu610072,China);Liu Zongxiang On the Failure Mechanism of a Bedding Landslide in Northeast Sichuan(Journal of Geological Hazards and Environment Preservation,ISSN1006-4362,CN51-1467/P,24(1),2013,p.14-19,2illus.,9refs.)Key words:bedding faults,landslides The landslide was caused by excavation engineering.The failure mechanism is explored for slopes with soft interlayer in the red

  6. Software engineering

    CERN Document Server

    Thorin, Marc

    1985-01-01

    Software Engineering describes the conceptual bases as well as the main methods and rules on computer programming. This book presents software engineering as a coherent and logically built synthesis and makes it possible to properly carry out an application of small or medium difficulty that can later be developed and adapted to more complex cases. This text is comprised of six chapters and begins by introducing the reader to the fundamental notions of entities, actions, and programming. The next two chapters elaborate on the concepts of information and consistency domains and show that a proc

  7. Engineering tribology

    CERN Document Server

    Stachowiak, Gwidon

    2013-01-01

    Engineering Tribology, 4th Edition is an established introductory reference focusing on the key concepts and engineering implications of tribology. Taking an interdisciplinary view, the book brings together the relevant knowledge from different fields needed to achieve effective analysis and control of friction and wear. Updated to cover recent advances in tribology, this new edition includes new sections on ionic and mesogenic lubricants, surface texturing, and multiscale characterization of 3D surfaces and coatings. Current trends in nanotribology are discussed, such as those relating to

  8. Lightwave engineering

    CERN Document Server

    Kokubun, Yasuo

    2012-01-01

    Suitable as either a student text or professional reference, Lightwave Engineering addresses the behavior of electromagnetic waves and the propagation of light, which forms the basis of the wide-ranging field of optoelectronics. Divided into two parts, the book first gives a comprehensive introduction to lightwave engineering using plane wave and then offers an in-depth analysis of lightwave propagation in terms of electromagnetic theory. Using the language of mathematics to explain natural phenomena, the book includes numerous illustrative figures that help readers develop an intuitive unders

  9. Engineering Research, Development and Technology, FY95: Thrust area report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-01

    The mission of the Engineering Research, Development, and Technology Program at Lawrence Livermore National Laboratory (LLNL) is to develop the knowledge base, process technologies, specialized equipment, tools and facilities to support current and future LLNL programs. Engineering`s efforts are guided by a strategy that results in dual benefit: first, in support of Department of Energy missions, such as national security through nuclear deterrence; and second, in enhancing the nation`s economic competitiveness through their collaboration with US industry in pursuit of the most cost-effective engineering solutions to LLNL programs. To accomplish this mission, the Engineering Research, Development, and Technology Program has two important goals: (1) identify key technologies relevant to LLNL programs where they can establish unique competencies, and (2) conduct high-quality research and development to enhance their capabilities and establish themselves as the world leaders in these technologies. To focus Engineering`s efforts, technology thrust areas are identified and technical leaders are selected for each area. The thrust areas are comprised of integrated engineering activities, staffed by personnel from the nine electronics and mechanical engineering divisions, and from other LLNL organizations. This annual report, organized by thrust area, describes Engineering`s activities for fiscal year 1995. The report provides timely summaries of objectives methods, and key results from eight thrust areas: computational electronics and electromagnetics; computational mechanics; microtechnology; manufacturing technology; materials science and engineering; power conversion technologies; nondestructive evaluation; and information engineering.

  10. Exact self-dual skyrmions

    Science.gov (United States)

    Ferreira, L. A.; Shnir, Ya.

    2017-09-01

    We introduce a Skyrme type model with the target space being the sphere S3 and with an action possessing, as usual, quadratic and quartic terms in field derivatives. The novel character of the model is that the strength of the couplings of those two terms are allowed to depend upon the space-time coordinates. The model should therefore be interpreted as an effective theory, such that those couplings correspond in fact to low energy expectation values of fields belonging to a more fundamental theory at high energies. The theory possesses a self-dual sector that saturates the Bogomolny bound leading to an energy depending linearly on the topological charge. The self-duality equations are conformally invariant in three space dimensions leading to a toroidal ansatz and exact self-dual Skyrmion solutions. Those solutions are labelled by two integers and, despite their toroidal character, the energy density is spherically symmetric when those integers are equal and oblate or prolate otherwise.

  11. DUAL Gamma-Ray Mission

    CERN Document Server

    Boggs, S; von Ballmoos, P; Takahashi, T; Gehrels, N; Tueller, J; Baring, M; Beacom, J; Diehl, R; Greiner, J; Grove, E; Hartmann, D; Hernanz, M; Jean, P; Johnson, N; Kanbach, G; Kippen, M; Knödlseder, J; Leising, M; Madejski, G; McConnell, M; Milne, P; Motohide, K; Nakazawa, K; Oberlack, U; Phlips, B; Ryan, J; Skinner, G; Starrfield, S; Tajima, H; Wulf, E; Zoglauer, A; Zych, A

    2010-01-01

    Gamma-ray astronomy presents an extraordinary scientific potential for the study of the most powerful sources and the most violent events in the Universe. In order to take full advantage of this potential, the next generation of instrumentation for this domain will have to achieve an improvement in sensitivity over present technologies of at least an order of magnitude. The DUAL mission concept takes up this challenge in two complementary ways: a very long observation of the entire sky, combined with a large collection area for simultaneous observations of Type Ia SNe. While the Wide-Field Compton Telescope (WCT) accumulates data from the full gamma-ray sky (0.1-10 MeV) over the entire mission lifetime, the Laue-Lens Telescope (LLT) focuses on 56Co emission from SNe Ia (0.8-0.9 MeV), collecting gamma-rays from its large area crystal lens onto the WCT. Two separated spacecraft flying in formation will maintain the DUAL payloads at the lens' focal distance.

  12. College Course Grades for Dual Enrollment Students

    Science.gov (United States)

    Crouse, Jill D.; Allen, Jeff

    2014-01-01

    This study compared college course grade outcomes, both during and after high school, of dual-enrollment students to those of traditional students. The study was based on a large, multiyear sample of Iowa high school and community college students. The results showed that while in high school, dual-enrollment students consistently outperformed…

  13. 7 CFR 7.17 - Dual office.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Dual office. 7.17 Section 7.17 Agriculture Office of... STATE, COUNTY AND COMMUNITY COMMITTEES § 7.17 Dual office. (a) County committee membership. A member of... any other county office employee. (b) Community committee membership. A member of the...

  14. Learning from the Past: Dual Credit

    Science.gov (United States)

    Mansell, Nicole; Justice, Madeline

    2014-01-01

    This study involved identifying, categorizing, and comparing critical incidents related to qualifying dual credit high school students' decisions to enroll or not to enroll in dual credit coursework in either a traditional or early college high school. The purpose of the study was (a) to identify the reasons qualifying students decide to enroll in…

  15. "Dual" Classes See Growth in Popularity

    Science.gov (United States)

    Maxwell, Lesli A.

    2012-01-01

    Growing numbers of schools are offering dual-language classes, where teachers split instruction between English and a second language. The numbers of dual-language-immersion programs have been steadily growing in public schools over the past decade or so, rising to more than 2,000 in 2011-12, according to estimates from national experts. That…

  16. Unraveling executive functioning in dual diagnosis

    NARCIS (Netherlands)

    Duijkers, J.C.L.M.; Vissers, C.T.W.M.; Egger, J.I.M.

    2016-01-01

    In mental health, the term dual-diagnosis is used for the co-occurrence of Substance Use Disorder (SUD) with another mental disorder. These co-occurring disorders can have a shared cause, and can cause/intensify each other's expression. Forming a threat to health and society, dual-diagnosis is assoc

  17. Theories of Dual Diagnosis in Mental Retardation.

    Science.gov (United States)

    Matson, Johnny L.; Sevin, Jay A.

    1994-01-01

    Provides historical review of theory development in the field of dual diagnosis, defined as co-occurrence of mental health disorders with mental retardation. Noting that current etiological theories have practical implications for treatment and prevention of dual diagnosis, discusses current status of etiological theories and future directions for…

  18. Photoreceptor engineering

    Directory of Open Access Journals (Sweden)

    Thea eZiegler

    2015-06-01

    Full Text Available Sensory photoreceptors not only control diverse adaptive responses in Nature, but as light-regulated actuators they also provide the foundation for optogenetics, the non-invasive and spatiotemporally precise manipulation of cellular events by light. Novel photoreceptors have been engineered that establish control by light over manifold biological processes previously inaccessible to optogenetic intervention. Recently, photoreceptor engineering has witnessed a rapid development, and light-regulated actuators for the perturbation of a plethora of cellular events are now available. Here, we review fundamental principles of photoreceptors and light-regulated allostery. Photoreceptors dichotomize into associating receptors that alter their oligomeric state as part of light-regulated allostery and non-associating receptors that do not. A survey of engineered photoreceptors pinpoints light-regulated association reactions and order-disorder transitions as particularly powerful and versatile design principles. Photochromic photoreceptors that are bidirectionally toggled by two light colors augur enhanced spatiotemporal resolution and use as photoactivatable fluorophores. By identifying desirable traits in engineered photoreceptors, we provide pointers for the design of future, light-regulated actuators.

  19. Exhibit Engineering

    DEFF Research Database (Denmark)

    Mortensen, Marianne Foss

    ) a synthesis of the findings from the first two studies with findings from the literature to generate two types of results: a coherent series of suggestions for a design iteration of the studied exhibit as well as a more general normative model for exhibit engineering. Finally, another perspective...

  20. Concurrent engineering

    Science.gov (United States)

    Chamis, C. C.; Leger, L.; Hunter, D.; Jones, C.; Sprague, R.; Berke, L.; Newell, J.; Singhal, S.

    1991-01-01

    The following subject areas are covered: issues (liquid rocket propulsion - current development approach, current certification process, and costs of engineering changes); state of the art (DICE information management system, key government participants, project development strategy, quality management, and numerical propulsion system simulation); needs identified; and proposed program.

  1. Geospatial Engineering

    Science.gov (United States)

    2017-02-22

    drinking , sanitation, food preparation, construction, and decontamination. Support activities (helicopter maintenance , operation of medical facilities...analyses to find water sources for wells and key infrastructure locations. There are additional missions performed by geospatial engineers during the...polygons). Each feature can include embedded information (attributes) (body- of- water bank heights, road surface type, road width, bridge load-bearing

  2. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    <正>20051144 Gu Jun (Petroleum University, Beijing); Gao Deli Analysis of Mechanic Characterstics for Coal Bed and Drilling Countermeasure in Tuha Basin, Xinjiang, China (Exploration Engineering (Rock & Soil Drilling and Tunneling), ISSN 1672 - 7428, CN11-5063/TD, 31(5), 2004, p. 51-52, 55, 3 tables, 1 ref. , with English abstract) Key words: coal seams, drilling

  3. Micro Engineering

    DEFF Research Database (Denmark)

    Alting, Leo; Kimura, F.; Hansen, Hans Nørgaard

    2003-01-01

    The paper addresses the questions of how micro products are designed and how they are manufactured. Definitions of micro products and micro engineering are discussed and the presentation is aimed at describing typical issues, possibilities and tools regarding design of micro products. The implica...

  4. Concurrency engineering

    NARCIS (Netherlands)

    Jesshope, C.; Shafarenko, A.

    2008-01-01

    This is a discussion paper on a very important topic that is about to become mainstream. It deals with the issues of software engineering in concurrent systems. It introduces this topic and illustrates the arguments for a change of perspective. It underlines these arguments with two examples, an

  5. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    20161419Cao Baomin(Shaanxi Binchang Xiaozhuang Mining Co.Ltd,Binxian 7135000,China);Zhang Jianghao Application of Rotary Drilling Combination to Pile Foundation Engineering in Xiaozhuang Mine,Shaanxi Province(Geology of Shaanxi,ISSN1001-6996,CN61

  6. Engineering Ontologies

    NARCIS (Netherlands)

    Borst, Pim; Akkermans, Hans; Top, Jan

    1997-01-01

    We analyse the construction as well as the role of ontologies in knowledge sharing and reuse for complex industrial applications. In this article, the practical use of ontologies in large-scale applications not restricted to knowledge-based systems is demonstrated, for the domain of engineering syst

  7. In vivo tomographic imaging with fluorescence and MRI using tumor-targeted dual-labeled nanoparticles

    Directory of Open Access Journals (Sweden)

    Zhang Y

    2013-12-01

    Full Text Available Yue Zhang,1 Bin Zhang,1 Fei Liu,1,2 Jianwen Luo,1,3 Jing Bai1 1Department of Biomedical Engineering, School of Medicine, 2Tsinghua-Peking Center for Life Sciences, 3Center for Biomedical Imaging Research, Tsinghua University, Beijing, People's Republic of China Abstract: Dual-modality imaging combines the complementary advantages of different modalities, and offers the prospect of improved preclinical research. The combination of fluorescence imaging and magnetic resonance imaging (MRI provides cross-validated information and direct comparison between these modalities. Here, we report on the application of a novel tumor-targeted, dual-labeled nanoparticle (NP, utilizing iron oxide as the MRI contrast agent and near infrared (NIR dye Cy5.5 as the fluorescent agent. Results of in vitro experiments verified the specificity of the NP to tumor cells. In vivo tumor targeting and uptake of the NPs in a mouse model were visualized by fluorescence and MR imaging collected at different time points. Quantitative analysis was carried out to evaluate the efficacy of MRI contrast enhancement. Furthermore, tomographic images were also acquired using both imaging modalities and cross-validated information of tumor location and size between these two modalities was revealed. The results demonstrate that the use of dual-labeled NPs can facilitate the dual-modal detection of tumors, information cross-validation, and direct comparison by combing fluorescence molecular tomography (FMT and MRI. Keywords: dual-modality, fluorescence molecular tomography (FMT, magnetic resonance imaging (MRI, nanoparticle

  8. Self-Dual Weak Hopf Algebras

    Institute of Scientific and Technical Information of China (English)

    Munir AHMED; Fang LI

    2008-01-01

    In this paper, we define the notion of self-dual graded weak Hopf algebra and self-dual semilattice graded weak Hopf algebra. We give characterization of finite-dimensional such algebras when they are in structually simple forms in the sense of E. L. Green and E. N. Morcos. We also give the definition of self-dual weak Hopf quiver and apply these types of quivers to classify the finite-dimensional self-dual semilattice graded weak Hopf algebras. Finally, we prove partially the conjecture given by N. Andruskiewitsch and H.-J. Schneider in the case of finite-dimensional pointed semilattice graded weak Hopf algebra H when grH is self-dual.

  9. Enhancing Engineering Education through Engineering Management

    Science.gov (United States)

    Pence, Kenneth R.; Rowe, Christopher J.

    2012-01-01

    Engineering Management courses are added to a traditional engineering curriculum to enhance the value of an undergraduate's engineering degree. A four-year engineering degree often leaves graduates lacking in business and management acumen. Engineering management education covers topics enhancing the value of new graduates by teaching management…

  10. El anillo de los números duales

    OpenAIRE

    Jiménez, Haydee; Luque, Carlos Julio

    2007-01-01

    Se inicia con una presentación de la estructura de * - Álgebra de los números duales; se muestran diferentes representaciones que permiten la definición de potencias racionales de números duales, lo que exige una extensión de su estructura a un anillo de números duales con coeficientes complejos. Seguidamente se estudian la función exponencial dual y la función logaritmo dual que permiten la definición de potencias duales de un número dual; luego se estudian ecuaciones en los números duales h...

  11. El anillo de los números duales

    OpenAIRE

    Jiménez, Haydee; Luque, Carlos Julio

    2007-01-01

    Se inicia con una presentación de la estructura de * - Álgebra de los números duales; se muestran diferentes representaciones que permiten la definición de potencias racionales de números duales, lo que exige una extensión de su estructura a un anillo de números duales con coeficientes complejos. Seguidamente se estudian la función exponencial dual y la función logaritmo dual que permiten la definición de potencias duales de un número dual; luego se estudian ecuaciones en los números duales h...

  12. Engineering Review Information System

    Science.gov (United States)

    Grems, III, Edward G. (Inventor); Henze, James E. (Inventor); Bixby, Jonathan A. (Inventor); Roberts, Mark (Inventor); Mann, Thomas (Inventor)

    2015-01-01

    A disciplinal engineering review computer information system and method by defining a database of disciplinal engineering review process entities for an enterprise engineering program, opening a computer supported engineering item based upon the defined disciplinal engineering review process entities, managing a review of the opened engineering item according to the defined disciplinal engineering review process entities, and closing the opened engineering item according to the opened engineering item review.

  13. Dual use of tobacco among Bangladeshi men

    Directory of Open Access Journals (Sweden)

    M M Zaman

    2014-01-01

    Full Text Available Introduction: Dual use of tobacco (using smoking and smokeless forms in Bangladesh is uncommon in women but common in men. Dual users are at additional risk of cancers and heart diseases compared with a single form of tobacco use. Knowledge about their socioeconomic background is necessary for planning appropriate interventions. We report here socioeconomic background of the dual users of tobacco from a nationally representative survey. Methods: The study adopted a probability proportionate to size sampling technic of divisional population stratified into urban and rural areas to recruit men aged 25 years or older from their households. A total of 4312 men were recruited. Variables included questions on 20 household assets, tobacco use and other behavioral risk factors, and measurement of body weight and height. Results: The average age of dual users was 46.7 years old compared to 43.4 and 52.3 years for smokers and smokeless tobacco users. Prevalence of "smoking only," "smokeless only" and "dual use" of tobacco was 40.6%, 15.2%, and 14.2%, respectively. Among all tobacco users, dual users constituted 20%. These dual users had lower educational achievement, rural residence, lower intake of fruit, and higher intake of alcohol. They were more undernourished as indicated by a thin body mass index compared to nonusers and smokers. Dual users were of socioeconomically deprived as measured by wealth quartiles constructed out of household assets. Conclusion: Dual use of tobacco is common in Bangladesh, and it is intimately linked with socioeconomic deprivation. Poverty reduction strategy and campaigns should address tobacco control not only tobacco in general, but its dual use in particular.

  14. A graphics approach in the design of the dual air density Explorer satellites

    Science.gov (United States)

    Mcdougal, D. S.

    1975-01-01

    A computer program was developed to generate a graphics display of the Dual Air Density (DAD) Explorer satellites which aids in the engineering and scientific design. The program displays a two-dimensional view of both spacecraft and their surface features from any direction. The graphics have been an indispensable tool in the design, analysis, and understanding of the critical locations of the various surface features for both satellites.

  15. Construction of Chimeric Dual-Chain Avidin by Tandem Fusion of the Related Avidins

    OpenAIRE

    Riihimäki, Tiina A; Sampo Kukkurainen; Suvi Varjonen; Jarno Hörhä; Nyholm, Thomas K M; Kulomaa, Markku S; Hytönen, Vesa P.

    2011-01-01

    BACKGROUND: Avidin is a chicken egg-white protein with high affinity to vitamin H, also known as D-biotin. Many applications in life science research are based on this strong interaction. Avidin is a homotetrameric protein, which promotes its modification to symmetrical entities. Dual-chain avidin, a genetically engineered avidin form, has two circularly permuted chicken avidin monomers that are tandem-fused into one polypeptide chain. This form of avidin enables independent modification of t...

  16. 燃烧室工作过程对冲压发动机性能潜力的影响研究%Study on the relation between performance and process in combustor for dual-mode and ram jet engine

    Institute of Scientific and Technical Information of China (English)

    陈军; 白菡尘; 柳森

    2013-01-01

    In this paper the relation between the process and performance in a dual-mode and a ram (subsonic) combustor is studied with a quasi one-dimensional method.It is proposed that the two kinds of combustors have the same incoming flow conditions when the flight Mach numbers are the same,and the fuel energy is fully added into the flow with the equilibrium ratio of 1.A term of combustor characteristic Mach number is defined in this paper.In a subsonic combustor,it is the Mach number at the section just upstream the nozzle; In a dual-mode combustor,it is that in a divergent part where the flow Mach number will keep constant.The results indicate that,with the same incoming condition,the needed divergent ratio of the subsonic combustor decreased and that of the dual-mode combustor increased as the combustor characteristic Mach number increased.For the subsonic combustor,the minimal divergent ratio and maximal performance correspond to the characteristic Mach number of 1 and 0 respectively.For the dual-mode combustor with the minimal divergent ratio,the maximal performance is achieved when the characteristic Mach number tends to be minimal.The minimal divergent ratio for the two kinds of combustors is about the same.The maximal performance for the dual-mode combustor is a little lower than that for the subsonic one.At flight Mach number of 4,5 and 6,the difference is about 5%,4% and 3% respectively.The combustor divergent ratio is affected by the wall friction seriously,but the performance slightly.A few experiment results obtained in a direct-connected combustion test with a dual-mode combustor and transformed into the heat-limit for the correspond section,have validated this method.%用准一维分析方法,在相同的入流条件下,假设将当量比为1的燃料热量全部添加到气流中,研究了燃烧室工作过程与性能之间的关系.结果表明,随着特征马赫数的增加,在相同飞行马赫数下,亚声速燃烧室所需扩张比逐渐减

  17. Quantum dynamics in dual spaces

    Energy Technology Data Exchange (ETDEWEB)

    Sudarshan, E.C.G.

    1993-12-31

    Quantum mechanics gives us information about spectra of dynamical variables and transition rates including scattering cross sections. They can be exhibited as spectral information in analytically continued spaces and their duals. Quantum mechanics formulated in these generalized spaces is used to study scattering and time evolution. It is shown that the usual asymptotic condition is inadequate to deal with scattering of composite or unstable particles. Scattering theory needs amendment when the interacting system is not isospectral with the free Hamiltonian, and the amendment is formulated. Perturbation theory in generalized spaces is developed and used to study the deletion and augmentation of the spectrum of the Hamiltonian. A complete set of algebraically independent constants for an interacting system is obtained. The question of the breaking of time symmetry is discussed.

  18. Dual Watermarking Scheme with Encryption

    CERN Document Server

    Dhanalakshmi, R

    2010-01-01

    Digital Watermarking is used for copyright protection and authentication. In the proposed system, a Dual Watermarking Scheme based on DWT SVD with chaos encryption algorithm, will be developed to improve the robustness and protection along with security. DWT and SVD have been used as a mathematical tool to embed watermark in the image. Two watermarks are embedded in the host image. The secondary is embedded into primary watermark and the resultant watermarked image is encrypted using chaos based logistic map. This provides an efficient and secure way for image encryption and transmission. The watermarked image is decrypted and a reliable watermark extraction scheme is developed for the extraction of the primary as well as secondary watermark from the distorted image.

  19. Dual Syntax for XML Languages

    DEFF Research Database (Denmark)

    Brabrand, Claus; Møller, Anders; Schwartzbach, Michael Ignatieff

    2008-01-01

    XML is successful as a machine processable data interchange format, but it is often too verbose for human use. For this reason, many XML languages permit an alternative more legible non-XML syntax. XSLT stylesheets are often used to convert from the XML syntax to the alternative syntax; however......, such transformations are not reversible since no general tool exists to automatically parse the alternative syntax back into XML. We present XSugar, which makes it possible to manage dual syntax for XML languages. An XSugar specification is built around a context-free grammar that unifies the two syntaxes...... of a language. Given such a specification, the XSugar tool can translate from alternative syntax to XML and vice versa. Moreover, the tool statically checks that the transformations are reversible and that all XML documents generated from the alternative syntax are valid according to a given XML schema....

  20. Dual Syntax for XML Languages

    DEFF Research Database (Denmark)

    Brabrand, Claus; Møller, Anders; Schwartzbach, Michael Ignatieff

    2005-01-01

    XML is successful as a machine processable data interchange format, but it is often too verbose for human use. For this reason, many XML languages permit an alternative more legible non-XML syntax. XSLT stylesheets are often used to convert from the XML syntax to the alternative syntax; however......, such transformations are not reversible since no general tool exists to automatically parse the alternative syntax back into XML. We present XSugar, which makes it possible to manage dual syntax for XML languages. An XSugar specification is built around a context-free grammar that unifies the two syntaxes...... of a language. Given such a specification, the XSugar tool can translate from alternative syntax to XML and vice versa. Moreover, the tool statically checks that the transformations are reversible and that all XML documents generated from the alternative syntax are valid according to a given XML schema....

  1. The new 1.8 l TFSI engine from Audi. Pt. 1. Base engine and thermomanagement

    Energy Technology Data Exchange (ETDEWEB)

    Eiser, Alex; Jung, Michael; Adam, Stephan [Audi AG, Ingolstadt (Germany). Engine Development Dept.; Doerr, Joachim [Audi AG, Ingolstadt (Germany). Longitudinally Mounted Engines Dept.

    2011-06-15

    The launch of the new 1.8 l TFSI engine marks the third generation of the successful four-cylinder gasoline engine family from Audi. It has been completely revised in order to meet ambitious CO{sub 2} targets and ensure compliance with future Euro 6 emissions standards. The new generation features numerous innovative technologies, including an exhaust gas cooling system integrated into the cylinder head, a dual fuel injection system with direct and port-fuel injection as well as the Audi valvelift system with twin camshaft adjustment. A new-style fully electronic coolant control also enables an innovative thermomanagement system to be implemented. This first part of the article details the base engine and the thermomanagement system of the new engine. The second part of the article, which will be published in MTZ 7/8, covers the mixture formation, the combustion method and the turbocharging. (orig.)

  2. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20092040 Chen Jing(College of Petroleum Engineering,Yangtze University,Jingzhou 434023,China);Xiong Qingshan Technology of Well Cementing with Expandable Tube and Its Application(Exploration Engineering,ISSN1672-7428,CN11-5063/TD,35(8),2008,p.19-21,4 illus.,2 tables,5 refs.)Key words:cementingExpandable tube is a new technology and has been developed oversea.It can be applied in well drilling and completion for deep water,deep well,extended reach well and multilateral well,as well as in oil extraction and workover.This paper briefly introduces the technology of well cementing with

  3. Chart Venture Partners' perspective on dual-use CBRNE technologies

    Science.gov (United States)

    Van Nice, C. S.; Gardner, P. J.

    2008-04-01

    Chart Venture Partners' (CVP) approach to investing in Chemical, Biological, Radiological, Nuclear, and Explosives (CBRNE) detection technologies can be best understood in the context of the unique partnership between the firm's two founding institutions. CVP was founded as a partnership between the Chart Group, a New York-based merchant banking and venture capital boutique, and InSitech Incorporated, a 501(c)(3) non-profit commercial partnership intermediary for the U.S. Army's Armament Research Development and Engineering Center (ARDEC) at Picatinny Arsenal in New Jersey. The partnership between Chart Group and Insitech has yielded a new investment model. Unlike most venture funds, CVP operates with a singular focus on early-stage defense and security technologies, with the important caveat that everything we invest in must also have dual-use application in large-scale commercial markets. CVP believes that early-stage CBRNE companies require five qualities to be viable investment candidates and successful start-up companies: Great Science, Strong IP Positions, Recognized Scientific Champions, Identified Dual-Use Market Pull, and "Real World" Technical Performance Data. When earlystage CBRNE companies decide to seek venture capital and pursue higher growth dual-use business models, we often find that certain issues arise that are not always fully contemplated at the outset, and that can create gaps between what the start-up companies are offering to investors and what those investors are seeking from their potential portfolio companies. These same issues can have significant positive or negative impact on shareholder value over time, depending on how they are managed. Specifically, startups should consider carefully their strategies related to business development, market positioning, government funding, and investment syndicate formation.

  4. Heat engines

    Science.gov (United States)

    Rekos, N. F., Jr.; Parsons, E. L., Jr.

    1989-09-01

    For the past decade, the Department of Energy (DOE) has sponsored projects to develop diesel and gas turbine engines capable of operating on low-cost, coal-based fuels. Much of the current work addresses the use of coal-water fuel (CWF) in diesel and turbines, although there is some work with dry coal feed and other coal fuels. Both the diesel and gas turbine portions of the program include proof-of-concept and support projects. Specific highlights of the program include: engine tests and economic analyses have shown that CWF can replace 70 percent of the diesel oil used in the duty cycle of a typical main-line locomotive; A. D. Little and Cooper-Bessemer completed a system and economic study of coal-fueled diesel engines for modular power and industrial cogeneration markets. The coal-fueled diesel was found to be competitive at fuel oil prices of $5.50 per million British thermal units (MBtu); Over 200 hours of testing have been completed using CWF in full-scale, single-cylinder diesel engines. Combustion efficiencies have exceeded 99 percent; Both CWF and dry coal fuel forms can be burned in short residence time in-line combustors and in off-base combustors with a combustion efficiency of over 99 percent; Rich/lean combustion systems employed by the three major DOE contractors have demonstrated low NO(sub x) emissions levels; Contractors have also achieved promising results for controlling sulfur oxide (SO(sub x)) emissions using calcium-based sorbents; Slagging combustors have achieved between 65 and 95 percent slag capture, which will limit particulate loading on pre-turbine cleanup devices. For many of the gas turbine and diesel applications emission standards do not exist. Our goal is to develop coal-fueled diesels and gas turbines that not only meet all applicable emission standards that do exist, but also are capable of meeting possible future standards.

  5. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20090712 Ge Mingjun(General Institution of Mineral Exploration & Development in Qiqihaer of Heilongjiang Province,Qiqihaer 161006,China) Application of Emulsified Diesel Oil Drilling Fluid in Under-Balanced Drilling(Exploration Engineering(Rock & Soil Drilling and Tunneling),ISSN1672-7428,CN11-5063/TD,34(11),2007,p.43-45,1 illus.,2 tables,4 refs.)

  6. Engineering Ontologies

    OpenAIRE

    Borst, Pim; Akkermans, Hans; Top, Jan

    1997-01-01

    We analyse the construction as well as the role of ontologies in knowledge sharing and reuse for complex industrial applications. In this article, the practical use of ontologies in large-scale applications not restricted to knowledge-based systems is demonstrated, for the domain of engineering systems modelling, simulation and design. A general and formal ontology, called PHYSSYS, for dynamic physical systems is presented and its structuring principles are discussed. We show how the PHYSSYS ...

  7. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>20072985 Bai Mingzhou(Beijing Jiaotong University,Beijing 100044,China);Du Yongqiang Study on Application Technology of Geology Horizontal Drilling in Qiyueshan Tunnel at Yiwan Railway(Exploration Engineering(Rock & Soil Drilling and Tunneling),ISSN1672-7428,CN11-5063/TD,33(4),2006,p.59-61,1 table,3 refs.)Key words:tunnels,horizontal drilling

  8. Web Engineering

    Energy Technology Data Exchange (ETDEWEB)

    White, Bebo

    2003-06-23

    Web Engineering is the application of systematic, disciplined and quantifiable approaches to development, operation, and maintenance of Web-based applications. It is both a pro-active approach and a growing collection of theoretical and empirical research in Web application development. This paper gives an overview of Web Engineering by addressing the questions: (a) why is it needed? (b) what is its domain of operation? (c) how does it help and what should it do to improve Web application development? and (d) how should it be incorporated in education and training? The paper discusses the significant differences that exist between Web applications and conventional software, the taxonomy of Web applications, the progress made so far and the research issues and experience of creating a specialization at the master's level. The paper reaches a conclusion that Web Engineering at this stage is a moving target since Web technologies are constantly evolving, making new types of applications possible, which in turn may require innovations in how they are built, deployed and maintained.

  9. Novel CFT duals for extreme black holes

    Energy Technology Data Exchange (ETDEWEB)

    Chen Bin, E-mail: bchen01@pku.edu.cn [Department of Physics, and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Center for High Energy Physics, Peking University, Beijing 100871 (China); Zhang Jiaju, E-mail: jjzhang@pku.edu.cn [Department of Physics, and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China)

    2012-03-11

    In this paper, we study the CFT duals for extreme black holes in the stretched horizon formalism. We consider the extremal RN, Kerr-Newman-AdS-dS, as well as the higher dimensional Kerr-AdS-dS black holes. In all these cases, we reproduce the well-established CFT duals. Actually we show that for stationary extreme black holes, the stretched horizon formalism always gives rise to the same dual CFT pictures as the ones suggested by ASG of corresponding near horizon geometries. Furthermore, we propose new CFT duals for 4D Kerr-Newman-AdS-dS and higher dimensional Kerr-AdS-dS black holes. We find that every dual CFT is defined with respect to a rotation in certain angular direction, along which the translation defines a U(1) Killing symmetry. In the presence of two sets of U(1) symmetry, the novel CFT duals are generated by the modular group SL(2,Z), and for n sets of U(1) symmetry there are general CFT duals generated by T-duality group SL(n,Z).

  10. Developing 3D microstructures for tissue engineering

    DEFF Research Database (Denmark)

    Mohanty, Soumyaranjan

    casting process to generate various large scale tissue engineering constructs with single pore geometry with the desired mechanical stiffness and porosity. In addition, a new technique was developed to fa bricate dual-pore scaffolds for various tissue-engineering applications where 3D printing...... materials have been developed and tested for enhancing the differentiation of hiPSC-derived hepatocytes and fabricating biodegradable scaffolds for in-vivo tissue engineering applications. Along with various scaffolds fabrication methods we finally presented an optimized study of hepatic differentiation...... doxycycline was loaded into the hydrogel of the IPN materials, and the biological activity of released doxycycline was tested using a doxycycline regulated green fluorescent reporter gene expression assay in HeLa cells. Additionally, decellularized liver extracellular matrix (ECM) and natural silk protein...

  11. Understanding and mimicking the dual optimality of the fly ear.

    Science.gov (United States)

    Liu, Haijun; Currano, Luke; Gee, Danny; Helms, Tristan; Yu, Miao

    2013-01-01

    The fly Ormia ochracea has the remarkable ability, given an eardrum separation of only 520 μm, to pinpoint the 5 kHz chirp of its cricket host. Previous research showed that the two eardrums are mechanically coupled, which amplifies the directional cues. We have now performed a mechanics and optimization analysis which reveals that the right coupling strength is key: it results in simultaneously optimized directional sensitivity and directional cue linearity at 5 kHz. We next demonstrated that this dual optimality is replicable in a synthetic device and can be tailored for a desired frequency. Finally, we demonstrated a miniature sensor endowed with this dual-optimality at 8 kHz with unparalleled sound localization. This work provides a quantitative and mechanistic explanation for the fly's sound-localization ability from a new perspective, and it provides a framework for the development of fly-ear inspired sensors to overcoming a previously-insurmountable size constraint in engineered sound-localization systems.

  12. Revisiting impressions using dual-arch trays.

    Science.gov (United States)

    Small, Bruce W

    2012-01-01

    Making routine perfect impressions is the goal of any restorative dentist. Using dual-arch trays is an easy, repeatable way to accomplish that goal, as long as each step is done before the next and each step is performed perfectly. This column reviewed several articles that support the metal dual-arch concept and provided some clinical tips that might help restorative dentists. The dual-arch technique does have its limits and is meant for one or two teeth in a quadrant when there are other teeth to occlude with. Also, if the case involves anterior guidance, a full-arch impression maybe advisable.

  13. Dual accelerating Airy-Talbot recurrence effect

    CERN Document Server

    Zhang, Yiqi; Belić, Milivoj R; Liu, Xing; Zhong, Weiping; Zhang, Yanpeng; Xiao, Min

    2015-01-01

    We demonstrate the dual accelerating Airy-Talbot recurrence effect, i.e., the self-imaging of accelerating optical beams, by propagating a superposition of Airy beams with successively changing transverse displacements. The dual Airy-Talbot effect is a spontaneous recurring imaging of the input and of the input with alternating component signs. It results from the constructive interference of Airy wave functions, which is also responsible for other kinds of Airy beams, for example, Airy breathers. An input composed of finite-energy Airy beams also displays the dual Airy-Talbot effect, but it demands a large transverse displacement and diminishes fast along the propagation direction.

  14. Dual Lattice of ℤ-module Lattice

    Directory of Open Access Journals (Sweden)

    Futa Yuichi

    2017-07-01

    Full Text Available In this article, we formalize in Mizar [5] the definition of dual lattice and their properties. We formally prove that a set of all dual vectors in a rational lattice has the construction of a lattice. We show that a dual basis can be calculated by elements of an inverse of the Gram Matrix. We also formalize a summation of inner products and their properties. Lattice of ℤ-module is necessary for lattice problems, LLL(Lenstra, Lenstra and Lovász base reduction algorithm and cryptographic systems with lattice [20], [10] and [19].

  15. Near-Optimal Operation of Dual-Fuel Launch Vehicles

    Science.gov (United States)

    Ardema, M. D.; Chou, H. C.; Bowles, J. V.

    1996-01-01

    A near-optimal guidance law for the ascent trajectory from earth surface to earth orbit of a fully reusable single-stage-to-orbit pure rocket launch vehicle is derived. Of interest are both the optimal operation of the propulsion system and the optimal flight path. A methodology is developed to investigate the optimal throttle switching of dual-fuel engines. The method is based on selecting propulsion system modes and parameters that maximize a certain performance function. This function is derived from consideration of the energy-state model of the aircraft equations of motion. Because the density of liquid hydrogen is relatively low, the sensitivity of perturbations in volume need to be taken into consideration as well as weight sensitivity. The cost functional is a weighted sum of fuel mass and volume; the weighting factor is chosen to minimize vehicle empty weight for a given payload mass and volume in orbit.

  16. Internet Search Engines

    OpenAIRE

    Fatmaa El Zahraa Mohamed Abdou

    2004-01-01

    A general study about the internet search engines, the study deals main 7 points; the differance between search engines and search directories, components of search engines, the percentage of sites covered by search engines, cataloging of sites, the needed time for sites appearance in search engines, search capabilities, and types of search engines.

  17. Internet Search Engines

    Directory of Open Access Journals (Sweden)

    Fatmaa El Zahraa Mohamed Abdou

    2004-09-01

    Full Text Available A general study about the internet search engines, the study deals main 7 points; the differance between search engines and search directories, components of search engines, the percentage of sites covered by search engines, cataloging of sites, the needed time for sites appearance in search engines, search capabilities, and types of search engines.

  18. On R-duals and the duality principle

    DEFF Research Database (Denmark)

    Christensen, Ole; Stoeva, Diana

    2015-01-01

    . In this paper we discuss the relationship between the R-duals and a variant, called R-duals of type III, introduced in 2014. In contrast to the original R-duals, it is known that the R-duals of type III generalize the duality principle for all Gabor frames, but we believe that a smaller and more convenient...

  19. 46 CFR 129.326 - Dual-voltage generators.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Dual-voltage generators. 129.326 Section 129.326... INSTALLATIONS Power Sources and Distribution Systems § 129.326 Dual-voltage generators. If a dual-voltage generator is installed on an OSV— (a) The neutral of the dual-voltage system must be solidly grounded at...

  20. 46 CFR 120.324 - Dual voltage generators.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Dual voltage generators. 120.324 Section 120.324... INSTALLATION Power Sources and Distribution Systems § 120.324 Dual voltage generators. (a) A dual voltage generator installed on a vessel shall be of the grounded type, where: (1) The neutral of a dual...

  1. Properties of dual codes defined by nondegenerate forms

    Directory of Open Access Journals (Sweden)

    Steve Szabo

    2017-01-01

    Full Text Available Dual codes are defined with respect to non-degenerate sesquilinear or bilinear forms over a finite Frobenius ring. These dual codes have the properties one expects from a dual code: they satisfy a double-dual property, they have cardinality complementary to that of the primal code, and they satisfy the MacWilliams identities for the Hamming weight.

  2. Superalloy Disk With Dual-Grain Structure Spin Tested

    Science.gov (United States)

    Gayda, John; Kantzos, Pete T.

    2003-01-01

    Advanced nickel-base disk alloys for future gas turbine engines will require greater temperature capability than current alloys, but they must also continue to deliver safe, reliable operation. An advanced, nickel-base disk alloy, designated Alloy 10, was selected for evaluation in NASA s Ultra Safe Propulsion Project. Early studies on small test specimens showed that heat treatments that produced a fine grain microstructure promoted high strength and long fatigue life in the bore of a disk, whereas heat treatments that produced a coarse grain microstructure promoted optimal creep and crack growth resistance in the rim of a disk. On the basis of these results, the optimal combination of performance and safety might be achieved by utilizing a heat-treatment technology that could produce a fine grain bore and coarse grain rim in a nickel-base disk. Alloy 10 disks that were given a dual microstructure heat treatment (DMHT) were obtained from NASA s Ultra-Efficient Engine Technology (UEET) Program for preliminary evaluation. Data on small test specimens machined from a DMHT disk were encouraging. However, the benefit of the dual grain structure on the performance and reliability of the entire disk still needed to be demonstrated. For this reason, a high temperature spin test of a DMHT disk was run at 20 000 rpm and 1500 F at the Balancing Company of Dayton, Ohio, under the direction of NASA Glenn Research Center personnel. The results of that test showed that the DMHT disk exhibited significantly lower crack growth than a disk with a fine grain microstructure. In addition, the results of these tests could be accurately predicted using a two-dimensional, axisymmetric finite element analysis of the DMHT disk. Although the first spin test demonstrated a significant performance advantage associated with the DMHT technology, a second spin test on the DMHT disk was run to determine burst margin. The disk burst in the web at a very high speed, over 39 000 rpm, in line with

  3. Microprocessor engineering

    CERN Document Server

    Holdsworth, B

    2013-01-01

    Microprocessor Engineering provides an insight in the structures and operating techniques of a small computer. The book is comprised of 10 chapters that deal with the various aspects of computing. The first two chapters tackle the basic arithmetic and logic processes. The third chapter covers the various memory devices, both ROM and RWM. Next, the book deals with the general architecture of microprocessor. The succeeding three chapters discuss the software aspects of machine operation, while the last remaining three chapters talk about the relationship of the microprocessor with the outside wo

  4. Security Engineering

    Science.gov (United States)

    2012-01-31

    attacks cannot be completely addressed by traditional perimeter security solutions [ Wulf and Jones, 2009], as they have been in the past. A new...the mainstay of the current cyber security solution space [ Wulf and Jones, 2009]. This has enabled the system engineering and security communities...Number: H98230-08-D-0171 DO 002 TO 002 RT 028 Report No. SERC-2012-TR-028 January 31, 2012 UNCLASSIFIED 37 W. A. Wulf and A. K. Jones, Reflections on cyber security, Science Magazine, vol. 326, 2009, pp. 943-944.

  5. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    <正>20122758 Chen Huiming ( No.8 Geology Team of Fujian Province,Longyan 364000,China ) Application Research on Drilling Technology Process Combination for Deep Explora-tion in an Iron Mine of Fujian Province ( Exploration Engineering,ISSN1672-7428,CN11-5063 / TD,38 ( 9 ), 2011,p.6-9,8ta-bles,6refs. ) Key words:drilling in complicated formation According to the drilling technical problems in deep complex formations of the ironmine surrounding Makeng of Fujian Province ,

  6. The structure of dual Grassmann codes

    DEFF Research Database (Denmark)

    Beelen, Peter; Pinero, Fernando

    2016-01-01

    In this article we study the duals of Grassmann codes, certain codes coming from the Grassmannian variety. Exploiting their structure, we are able to count and classify all their minimum weight codewords. In this classification the lines lying on the Grassmannian variety play a central role....... Related codes, namely the affine Grassmann codes, were introduced more recently in Beelen et al. (IEEE Trans Inf Theory 56(7):3166–3176, 2010), while their duals were introduced and studied in Beelen et al. (IEEE Trans Inf Theory 58(6):3843–3855, 2010). In this paper we also classify and count the minimum...... weight codewords of the dual affine Grassmann codes. Combining the above classification results, we are able to show that the dual of a Grassmann code is generated by its minimum weight codewords. We use these properties to establish that the increase of value of successive generalized Hamming weights...

  7. Dual Enrollment Participation from the Student Perspective

    Science.gov (United States)

    Kanny, M. Allison

    2015-01-01

    This chapter examines the experiences of five high school students previously enrolled in dual enrollment courses, and discusses the perceived benefits and disadvantages of these experiences from the student perspective.

  8. Dual Eligibles and Potentially Avoidable Hospitalizations

    Data.gov (United States)

    U.S. Department of Health & Human Services — About 25 percent of the hospitalizations for dual eligible beneficiaries in 2005 were potentially avoidable. Medicare and Medicaid spending for those potentially...

  9. Dual Headquarters Involvement in Subsidiary Innovation

    DEFF Research Database (Denmark)

    Nell, Phillip Christopher; Kappen, Philip; Dellestrand, Henrik

    . The current paper takes on this neglected question by empirically investigating corporate and divisional headquarters direct involvement in innovation development projects at the subsidiary level. Analyses that draw upon 85 innovation development projects in 23 multinational enterprises reveal that dual...... innovation importance, i.e., an innovation that is important for the division and the corporate level, drives dual headquarters involvement in innovation development. Contrary to expectations, no significant effect of dual embeddedness on dual headquarters involvement is found. The network size...... on headquarters. It appears that multiple headquarters do get involved in specific subsidiary activities and that the theoretical advancements on headquarters should be discussed in the context of their complexity to reflect the nature of the contemporary multinational enterprise....

  10. Dual Career Marriages: Elements for Potential Success.

    Science.gov (United States)

    Maples, Mary F.

    1981-01-01

    Examines the family and work relationships of dual career couples and discusses the advantages and disadvantages of these relationships. Various ingredients including personality traits that contribute to the success of the two-career partnership are listed. (RC)

  11. Microresonator Soliton Dual-Comb Spectroscopy

    CERN Document Server

    Suh, Myoung-Gyun; Yang, Ki Youl; Yi, Xu; Vahala, Kerry

    2016-01-01

    Rapid characterization of optical and vibrational spectra with high resolution can identify species in cluttered environments and is important for assays and early alerts. In this regard, dual-comb spectroscopy has emerged as a powerful approach to acquire nearly instantaneous Raman and optical spectra with unprecedented resolution. Spectra are generated directly in the electrical domain and avoid bulky mechanical spectrometers. Recently, a miniature soliton-based comb has emerged that can potentially transfer the dual-comb method to a chip platform. Unlike earlier microcombs, these new devices achieve high-coherence, pulsed mode locking. They generate broad, reproducible spectral envelopes, which is essential for dual-comb spectroscopy. Here, dual-comb spectroscopy is demonstrated using these devices. This work shows the potential for integrated, high signal-to-noise spectroscopy with fast acquisition rates.

  12. Dual relations in physical and cyber space

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    With the rapid development of computer, communication, and sensing technology, our living space has been transformed from physical space into a space shared by physical space and cyberspace. In the light of this fact and based on analyzing the characteristics of physical and cyberspace, respectively, this paper proposed that there are dual relations between physical space and cyberspace. Establishing dual relations is realized in the following two processes: the process of information extraction, analysis and structurization from physical space to cyberspace and the process of providing the information services from cyberspace to physical space by means of inferring the intention, state and demand of users, as well. HCI (Human Cyberspace Interaction) in dual space means to establish the dual relations, which embodied the human centered HCI, i.e. the interaction is carried out in the way accustomed to users and without distracting their attention.

  13. Dual control vibration tests of flight hardware

    Science.gov (United States)

    Scharton, Terry D.

    1991-01-01

    A vibration retest of a spacecraft flight instrument, the Mars Observer Camera (MOC), was conducted using extremal dual control to automatically limit the shaker force and notch the shaker acceleration at resonances. This was the first application of extremal dual control with flight hardware at JPL. The retest was successful in that the environment was representative of flight plus some margin, the instrument survived without any structural or performance degradation, and the force limiting worked very well. The test set-up, force limiting procedure, and test results are described herein. It is concluded that dual control should be utilized when there is a concern about overtesting in hard-base-drive tests and the instrumentation for force measurement and control is available. Recommendations for improving the implementation of dual control are provided as a result of this first experience.

  14. Dual Eligibles and Potentially Avoidable Hospitalizations

    Data.gov (United States)

    U.S. Department of Health & Human Services — About 25 percent of the hospitalizations for dual eligible beneficiaries in 2005 were potentially avoidable. Medicare and Medicaid spending for those potentially...

  15. Simulation of dual transponder carrier ranging measurements

    Institute of Scientific and Technical Information of China (English)

    Xiang-yu ZHAO; Xiao-jun JIN; Zhong-he JIN

    2009-01-01

    The most dominant error source for microwave ranging is the frequency instability of the oscillator that generates the carrier phase signal. The oscillator noise is very difficult to filter due to its extremely low frequency. A dual transponder carrier ranging method can effectively minimize the oscillator noise by combing the reference phase and the to-and-fro measurement phase from the same single oscillator. This method does not require an accurate time tagging system, since it extracts phases on the same satellite. This paper analyzes the dual transponder carrier ranging system by simulation of the phase measurements with comprehensive error models. Both frequency domain and time domain noise transfer characteristics were simulated to compare them with dual one-way ranging. The simulation results in the two domains conformed to each other and demonstrated that a high level of accuracy can also be achieved by use of the dual transponder carrier ranging system, with relatively simple instruments.

  16. Physician dual practice: A review of literature

    DEFF Research Database (Denmark)

    Socha, Karolina; Bech, Mickael

    2010-01-01

    of dual practice effects for the public health care. Methods A systematic literature review identified 23 positions on the subject consisting of journal articles, academic working papers, book chapter, and publications of the WHO. Results The subject is short on evidence. Theoretical analyses indicate......Objectives A combination of public and private practice by physicians, referred to as physician dual practice, has been receiving attention in connection with arguments about its negative impact for the public health care. This paper aims to review and critically discuss findings on the subject...... both positive and negative effects of dual practice. Some of the effects depend, however, on assumptions that are undermined in the broader literature. The analyses assume that the dual practitioners’ objective is to maximise income. Yet, while physicians seem to engage in a private practice on top...

  17. Truncated Dual-Cap Nucleation Site Development

    Science.gov (United States)

    Matson, Douglas M.; Sander, Paul J.

    2012-01-01

    During heterogeneous nucleation within a metastable mushy-zone, several geometries for nucleation site development must be considered. Traditional spherical dual cap and crevice models are compared to a truncated dual cap to determine the activation energy and critical cluster growth kinetics in ternary Fe-Cr-Ni steel alloys. Results of activation energy results indicate that nucleation is more probable at grain boundaries within the solid than at the solid-liquid interface.

  18. Simulations of dual morphology in spiral galaxies

    CERN Document Server

    Berman, S L

    2003-01-01

    Gas and stars in spiral galaxies are modelled with the DUAL code, using hydrodynamic and N-body techniques. The simulations reveal morphological differences mirroring the dual morphologies seen in B and K' band observations of many spiral galaxies. In particular, the gaseous images are more flocculent with lower pitch angles than the stellar images, and the stellar arm-interarm contrast correlates with the degree of morphological decoupling.

  19. DUAL RANDOM MODEL OF INCREASING ANNUITY

    Institute of Scientific and Technical Information of China (English)

    HeWenjiong; ZhangYi

    2001-01-01

    The dual random models about the life insurance and social pension insurance have received considerable attention in the recent articles on actuarial theory and applications. This paper discusses a general kind of increasing annuity based on its force of interest accumulationfunction as a general random process. The dual random model of the present value of the benefits of the increasing annuity has been set, and their moments have been calculated under certainconditions.

  20. Fringe formation in dual-hologram interferometry

    Science.gov (United States)

    Burner, A. W.

    1990-01-01

    Reference-fringe formation in nondiffuse dual-hologram interferometry is described by combining a first-order geometrical hologram treatment with interference fringes generated by two point sources. The first-order imaging relationships can be used to describe reference-fringe patterns for the geometry of the dual-hologram interferometry. The process can be completed without adjusting the two holograms when the reconstructing wavelength is less than the exposing wavelength, and the process is found to facilitate basic intereferometer adjustments.

  1. Dual Brushless Resolver Rate Sensor

    Science.gov (United States)

    Howard, David E. (Inventor)

    1997-01-01

    A resolver rate sensor is disclosed in which dual brushless resolvers are mechanically coupled to the same output shaft. Diverse inputs are provided to each resolver by providing the first resolver with a DC input and the second resolver with an AC sinusoidal input. A trigonometric identity in which the sum of the squares of the sin and cosine components equal one is used to advantage in providing a sensor of increased accuracy. The first resolver may have a fixed or variable DC input to permit dynamic adjustment of resolver sensitivity thus permitting a wide range of coverage. In one embodiment of the invention the outputs of the first resolver are directly inputted into two separate multipliers and the outputs of the second resolver are inputted into the two separate multipliers, after being demodulated in a pair of demodulator circuits. The multiplied signals are then added in an adder circuit to provide a directional sensitive output. In another embodiment the outputs from the first resolver is modulated in separate modulator circuits and the output from the modulator circuits are used to excite the second resolver. The outputs from the second resolver are demodulated in separate demodulator circuit and added in an adder circuit to provide a direction sensitive rate output.

  2. Holographic duals of Boundary CFTs

    CERN Document Server

    Chiodaroli, Marco; Gutperle, Michael

    2012-01-01

    New families of regular half-BPS solutions to 6-dimensional Type 4b supergravity with $m$ tensor multiplets are constructed exactly. Their space-time consists of $AdS_2 \\times S^2$ warped over a Riemann surface with an arbitrary number of boundary components, and arbitrary genus. The solutions have an arbitrary number of asymptotic $AdS_3 \\times S^3$ regions. In addition to strictly single-valued solutions to the supergravity equations whose scalars live in the coset $SO(5,m)/SO(5)\\times SO(m)$, we also construct stringy solutions whose scalar fields are single-valued up to transformations under the $U$-duality group $SO(5,m;\\bZ)$, and live in the coset $SO(5,m;\\bZ)\\backslash SO(5,m)/SO(5)\\times SO(m)$. We argue that these Type 4b solutions are holographically dual to general classes of interface and boundary CFTs arising at the juncture of the end-points of 1+1-dimensional bulk CFTs. We evaluate their corresponding holographic entanglement and boundary entropy, and discuss their brane interpretation. We conj...

  3. Dual kidney transplantation: case report.

    Science.gov (United States)

    Vidas, Zeljko; Kocman, Branislav; Knotek, Mladen; Skegro, Dinko

    2010-06-01

    Chronic shortage of kidney transplants worldwide has led to the use of organs from so called marginal or borderline donors, now termed "expanded-criteria donors". There has been an emerging practice of dual kidney transplantation (DKT) to compensate for sub optimal nephron mass of such kidneys. We performed DKT in "Merkur" University Hospital in August 2005. The donor was a 72-year old female with a history of long-term hypertension, aneurysm of the posterior cerebral artery, cerebrovascular insult (CVI), and with normal creatinine values and kidney function at the time of explantation. Initial biopsy of donor kidneys revealed acute tubular damage, with connective changes in 22% and 11% of glomeruli in the left and the right kidney, respectively. The recipient was a 60-year old male diagnosed with the IgA nephropathy on the last biopsy in 1999, and on dialysis since November 2003. Postoperative course was uneventful without any surgical complications. A triple immunosuppressive protocol was used. On follow-up ultrasonography 4 years posttransplantation both kidneys appeared of normal size and parenchymal pattern and with no signs of dilatation of the canal system, and color Doppler examination demonstrated normal flow in both kidneys. In conclusion, the use of DKT ie. donors by the expanded-criteria will continue to increase, and further studies of the results will, with no doubt, support this method.

  4. A New Fenchel Dual Problem in Vector Optimization

    Indian Academy of Sciences (India)

    Radu Ioan Boţ; Anca Dumitru; Gert Wanka

    2009-04-01

    We introduce a new Fenchel dual for vector optimization problems inspired by the form of the Fenchel dual attached to the scalarized primal multiobjective problem. For the vector primal-dual pair we prove weak and strong duality. Furthermore, we recall two other Fenchel-type dual problems introduced in the past in the literature, in the vector case, and make a comparison among all three duals. Moreover, we show that their sets of maximal elements are equal.

  5. Nano surface engineering and remanufacture engineering

    Institute of Scientific and Technical Information of China (English)

    XU Bin-shi

    2004-01-01

    Nano surface engineering and remanufacture engineering are introduced, and the relationship between them is set forth. It points out the superiority of nano surface engineering to the traditional one, and reveals the advantages of remanufacture engineering. Taking some nano surface techniques as samples, such as nano-materials brush electroplating, nano-materials thermal spraying and nano-materials self-repairing antifriction additive technology, it shows the applications of nano surface engineering technology to remanufacturing mechanical parts.

  6. Studies on exhaust emissions of mahua oil operated compression ignition engine.

    Science.gov (United States)

    Kapilan, N; Reddy, R P

    2009-07-01

    The world is confronted with fossil fuel depletion and environmental degradation. The energy demand and pollution problems lead to research for an alternative renewable energy sources. Vegetable oils and biodiesel present a very promising alternative fuel to diesel. In this work, an experimental work was carried out to study the feasibility of using raw mahua oil (MO) as a substitute for diesel in dual fuel engine. A single cylinder diesel engine was modified to work in dual fuel mode and liquefied petroleum gas (LPG) was used as primary fuel and mahua oil was used as pilot fuel. The results show that the performance of the dual fuel engine at the injector opening pressure of 220 bar and the advanced injection timing of 30 degrees bTDC results in performance close to diesel base line (DBL) operation and lower smoke and oxides of nitrogen emission.

  7. Elementary Students' Acquisition of Academic Vocabulary Through Engineering Design

    Science.gov (United States)

    Kugelmass, Rachel

    This study examines how STEM (science, technology, engineering, and mathematics) inquiry-based learning through a hands-on engineering design can be beneficial in helping students acquire academic vocabulary. This research took place in a second grade dual- language classroom in a public, suburban elementary school. English language learners, students who speak Spanish at home, and native English speakers were evaluated in this study. Each day, students were presented with a general academic vocabulary focus word during an engineering design challenge. Vocabulary pre-tests and post-tests as well as observation field notes were used to evaluate the student's growth in reading and defining the focus academic vocabulary words. A quiz and KSB (knowledge and skill builder) packet were used to evaluate students' knowledge of science and math content and engineering design. The results of this study indicate that engineering design is an effective means for teaching academic vocabulary to students with varying levels of English proficiency.

  8. Dual Treatments as Starting Point for Integrative Perceptions in Teaching Mathematics

    Science.gov (United States)

    Kërënxhi, Svjetllana; Gjoci, Pranvera

    2015-01-01

    In this paper, we recommend mathematical teaching through dual treatments. The dual treatments notion, classified in dual interpretations, dual analyses, dual solutions, and dual formulations, is explained through concrete examples taken from mathematical textbooks of elementary education. Dual treatments provide opportunities for creating…

  9. Regenerative engineering

    CERN Document Server

    Laurencin, Cato T

    2013-01-01

    Regenerative Engineering: The Future of Medicine Saadiq F. El-Amin III , MD , PhD; Joylene W.L. Thomas, MD ; Ugonna N. Ihekweazu, MD ; Mia D. Woods, MS; and Ashim Gupta, MSCell Biology Gloria Gronowicz, PhD and Karen Sagomonyants, DMDStem Cells and Tissue Regeneration Kristen Martins-Taylor, PhD; Xiaofang Wang, MD , PhD; Xue-Jun Li, PhD; and Ren-He Xu, MD , PhDIntroduction to Materials Science Sangamesh G. Kumbar, PhD and Cato T. Laurencin, MD , PhDBiomaterials A. Jon Goldberg, PhD and Liisa T. Kuhn, PhDIn Vitro Assessment of Cell-Biomaterial Interactions Yong Wang, PhDHost Response to Biomate

  10. Engineering electromagnetics

    CERN Document Server

    Thomas, David T; Hartnett, James P; Hughes, William F

    1973-01-01

    The applications involving electromagnetic fields are so pervasive that it is difficult to estimate their contribution to the industrial output: generation of electricity, power transmission lines, electric motors, actuators, relays, radio, TV and microwave transmission and reception, magnetic storage, and even the mundane little magnet used to hold a paper note on the refrigerator are all electromagnetic in nature. One would be hard pressed to find a device that works without relaying on any electromagnetic principle or effect. This text provides a good theoretical understanding of the electromagnetic field equations but also treats a large number of applications. In fact, no topic is presented unless it is directly applicable to engineering design or unless it is needed for the understanding of another topic. In electrostatics, for example, the text includes discussions of photocopying, ink-jet printing, electrostatic separation and deposition, sandpaper production, paint spraying, and powder coating. In ma...

  11. Engineering viscoelasticity

    CERN Document Server

    Gutierrez-Lemini, Danton

    2014-01-01

    Engineering Viscoelasticity covers all aspects of the thermo- mechanical response of viscoelastic substances that a practitioner in the field of viscoelasticity would need to design experiments, interpret test data, develop stress-strain models, perform stress analyses, design structural components, and carry out research work. The material in each chapter is developed from the elementary to the advanced, providing the background in mathematics and mechanics that are central to understanding the subject matter being presented. The book examines how viscoelastic materials respond to the application of loads, and provides practical guidelines to use them in the design of commercial, military and industrial applications. This book also: ·         Facilitates conceptual understanding by progressing in each chapter from elementary to challenging material ·         Examines in detail both differential and integral constitutive equations, devoting full chapters to each type and using both forms in ...

  12. Reactor Engineering

    Science.gov (United States)

    Lema, Juan M.; López, Carmen; Eibes, Gemma; Taboada-Puig, Roberto; Moreira, M. Teresa; Feijoo, Gumersindo

    In this chapter, the engineering aspects of processes catalyzed by peroxidases will be presented. In particular, a discussion of the existing technologies that utilize peroxidases for different purposes, such as the removal of recalcitrant compounds or the synthesis of polymers, is analyzed. In the first section, the essential variables controlling the process will be investigated, not only those that are common in any enzymatic system but also those specific to peroxidative reactions. Next, different reactor configurations and operational modes will be proposed, emphasizing their suitability and unsuitability for different systems. Finally, two specific reactors will be described in detail: enzymatic membrane reactors and biphasic reactors. These configurations are especially valuable for the treatment of xenobiotics with high and poor water solubility, respectively.

  13. Effect of Modified Design on Engine Fuel Efficiency

    Directory of Open Access Journals (Sweden)

    Abdul Siddique Sk

    2016-09-01

    Full Text Available This paper covers key and representative developments in the area of high efficiency and cleans internal combustion engines. The main objective is to highlight recent efforts to improve (IC engine fuel efficiency and combustion. Rising fuel prices and stringent emission mandates have demanded cleaner combustion and increased fuel efficiency from the IC engine. This need for increased efficiency has placed compression ignition (CI engines in the forefront compared to spark ignition (SI engines. However, the relatively high emission of oxides of nitrogen (NOx and particulate matter (PM emitted by diesel engines increases their cost and raises environmental barriers that have prevented their widespread use in certain markets. The desire to increase IC engine fuel efficiency while simultaneously meeting emissions mandates has thus motivated considerable research. This paper describes recent progress to improve the fuel efficiency of diesel or CI engines through advanced combustion and fuels research. In particular, a dual fuel engine combustion technology called ―reactivity controlled compression ignition‖ (RCCI, which is a variant of Homogeneous Charge Compression Ignition (HCCI, is highlighted, since it provides more efficient control over the combustion process and has the capability to lower fuel use and pollutant emissions. This paper reviews recent RCCI experiments and computational studies performed on light- and heavy-duty engines, and compares results using conventional and alternative fuels (natural gas, ethanol, and biodiesel with conventional diesel, advanced diesel and HCCI concepts.

  14. Dual-Compartment Inflatable Suitlock

    Science.gov (United States)

    Kennedy, Kriss J.; Guirgis, Peggy L.; Boyle, Robert M.

    2013-01-01

    There is a need for an improvement over current NASA Extravehicular Activity (EVA) technology. The technology must allow the capacity for quicker, more efficient egress/ingress, allow for shirtsleeve suit maintenance, be compact in transport, and be applicable to environments ranging from planetary surface (partial-g) to orbital or deep space zero-g environments. The technology must also be resistant to dust and other foreign contaminants that may be present on or around a planetary surface. The technology should be portable, and be capable of docking with a variety of habitats, ports, stations, vehicles, and other pressurized modules. The Dual-Compartment Inflatable Suitlock (DCIS) consists of three hard inline bulkheads, separating two cylindrical membrane-walled compartments. The Inner Bulkhead can be fitted with a variety of hatch types, docking flanges, and mating hardware, such as the Common Berthing Mechanism (CBM), for the purpose of mating with vehicles, habitats, and other pressurized modules. The Inner Bulkhead and Center Bulkhead function as the end walls of the Inner Compartment, which during operations, would stay pressurized, either matching the pressure of the habitat or acting as a lower-pressure transitional volume. The Inner Compartment contains donning/doffing fixtures and inner suit-port hatches. The Center Bulkhead has two integrated suit-ports along with a maintenance hatch. The Center Bulkhead and Outer Bulkhead function as the end walls of the Outer Compartment, which stays at vacuum during normal operations. This allows the crewmember to quickly don a suit, and egress the suitlock without waiting for the Outer Compartment to depressurize. The Outer Compartment can be pressurized infrequently for both nominal and off-nominal suit maintenance tasks, allowing shirtsleeve inspections and maintenance/repair of the environmental suits. The Outer Bulkhead has a pressure-assisted hatch door that stays open and stowed during EVA operations, but can

  15. Dual Cryogenic Capacitive Density Sensor

    Science.gov (United States)

    Youngquist, Robert; Mata, Carlos; Vokrot, Peter; Cox, Robert

    2009-01-01

    A dual cryogenic capacitive density sensor has been developed. The device contains capacitive sensors that monitor two-phase cryogenic flow density to within 1% accuracy, which, if temperature were known, could be used to determine the ratio of liquid to gas in the line. Two of these density sensors, located a known distance apart, comprise the sensor, providing some information on the velocity of the flow. This sensor was constructed as a proposed mass flowmeter with high data acquisition rates. Without moving parts, this device is capable of detecting the density change within a two-phase cryogenic flow more than 100 times a second. Detection is enabled by a series of two sets of five parallel plates with stainless steel, cryogenically rated tubing. The parallel plates form the two capacitive sensors, which are measured by electrically isolated digital electronics. These capacitors monitor the dielectric of the flow essentially the density of the flow and can be used to determine (along with temperature) the ratio of cryogenic liquid to gas. Combining this information with the velocity of the flow can, with care, be used to approximate the total two-phase mass flow. The sensor can be operated at moderately high pressures and can be lowered into a cryogenic bath. The electronics have been substantially improved over the older sensors, incorporating a better microprocessor, elaborate ground loop protection and noise limiting circuitry, and reduced temperature sensitivity. At the time of this writing, this design has been bench tested at room temperature, but actual cryogenic tests are pending

  16. Dual-Pump Coherent Anti-Stokes Raman Scattering Temperature and CO2 Concentration Measurements

    Science.gov (United States)

    Lucht, Robert P.; Velur-Natarajan, Viswanathan; Carter, Campbell D.; Grinstead, Keith D., Jr.; Gord, James R.; Danehy, Paul M.; Fiechtner, G. J.; Farrow, Roger L.

    2003-01-01

    Measurements of temperature and CO2 concentration using dual-pump coherent anti-Stokes Raman scattering, (CARS) are described. The measurements were performed in laboratory flames,in a room-temperature gas cell, and on an engine test stand at the U.S. Air Force Research Laboratory, Wright-Patterson Air Force Base. A modeless dye laser, a single-mode Nd:YAG laser, and an unintensified back-illuminated charge-coupled device digital camera were used for these measurements. The CARS measurements were performed on a single-laser-shot basis. The standard deviations of the temperatures and CO2 mole fractions determined from single-shot dual-pump CARS spectra in steady laminar propane/air flames were approximately 2 and 10% of the mean values of approximately 2000 K and 0.10, respectively. The precision and accuracy of single-shot temperature measurements obtained from the nitrogen part of the dual-pump CARS system were investigated in detail in near-adiabatic hydrogen/air/CO2 flames. The precision of the CARS temperature measurements was found to be comparable to the best results reported in the literature for conventional two-laser, single-pump CARS. The application of dual-pump CARS for single-shot measurements in a swirl-stabilized combustor fueled with JP-8 was also demonstrated.

  17. Unraveling Executive Functioning in Dual Diagnosis

    Science.gov (United States)

    Duijkers, Judith C. L. M.; Vissers, Constance Th. W. M.; Egger, Jos I. M.

    2016-01-01

    In mental health, the term dual-diagnosis is used for the co-occurrence of Substance Use Disorder (SUD) with another mental disorder. These co-occurring disorders can have a shared cause, and can cause/intensify each other’s expression. Forming a threat to health and society, dual-diagnosis is associated with relapses in addiction-related behavior and a destructive lifestyle. This is due to a persistent failure to control impulses and the maintaining of inadequate self-regulatory behavior in daily life. Thus, several aspects of executive functioning like inhibitory, shifting and updating processes seem impaired in dual-diagnosis. Executive (dys-)function is currently even seen as a shared underlying key component of most mental disorders. However, the number of studies on diverse aspects of executive functioning in dual-diagnosis is limited. In the present review, a systematic overview of various aspects of executive functioning in dual-diagnosis is presented, striving for a prototypical profile of patients with dual-diagnosis. Looking at empirical results, inhibitory and shifting processes appear to be impaired for SUD combined with schizophrenia, bipolar disorder or cluster B personality disorders. Studies involving updating process tasks for dual-diagnosis were limited. More research that zooms in to the full diversity of these executive functions is needed in order to strengthen these findings. Detailed insight in the profile of strengths and weaknesses that underlies one’s behavior and is related to diagnostic classifications, can lead to tailor-made assessment and indications for treatment, pointing out which aspects need attention and/or training in one’s self-regulative abilities. PMID:27445939

  18. Unraveling Executive Functioning in Dual Diagnosis.

    Science.gov (United States)

    Duijkers, Judith C L M; Vissers, Constance Th W M; Egger, Jos I M

    2016-01-01

    In mental health, the term dual-diagnosis is used for the co-occurrence of Substance Use Disorder (SUD) with another mental disorder. These co-occurring disorders can have a shared cause, and can cause/intensify each other's expression. Forming a threat to health and society, dual-diagnosis is associated with relapses in addiction-related behavior and a destructive lifestyle. This is due to a persistent failure to control impulses and the maintaining of inadequate self-regulatory behavior in daily life. Thus, several aspects of executive functioning like inhibitory, shifting and updating processes seem impaired in dual-diagnosis. Executive (dys-)function is currently even seen as a shared underlying key component of most mental disorders. However, the number of studies on diverse aspects of executive functioning in dual-diagnosis is limited. In the present review, a systematic overview of various aspects of executive functioning in dual-diagnosis is presented, striving for a prototypical profile of patients with dual-diagnosis. Looking at empirical results, inhibitory and shifting processes appear to be impaired for SUD combined with schizophrenia, bipolar disorder or cluster B personality disorders. Studies involving updating process tasks for dual-diagnosis were limited. More research that zooms in to the full diversity of these executive functions is needed in order to strengthen these findings. Detailed insight in the profile of strengths and weaknesses that underlies one's behavior and is related to diagnostic classifications, can lead to tailor-made assessment and indications for treatment, pointing out which aspects need attention and/or training in one's self-regulative abilities.

  19. Detecting Dual AGN at High Redshift

    Science.gov (United States)

    Barrows, Robert S.

    2012-01-01

    The existence of supermassive black holes (SMBHs) in most, if not all, galaxies, along with observations of galaxy mergers, suggests that pairs of SMBHs should exist for some time in the merger remnant. Observational evidence for these systems at kpc-scale separations (i.e. dual AGN) has dramatically increased recently through a combination of spectral and morphological selections. I discuss observations of CXOXBJ142607.6+353351 (CXOJ1426+35), a candidate dual AGN at z=1.175, and put its properties, including significant obscuration, within the context of other candidate/confirmed dual AGN at lower redshifts. Though dual AGN are expected to be more common at higher redshifts, they are more difficult to detect. Furthermore, adding to the difficulties of detection are a number of other physical mechanisms which can mimic the spectroscopic signature of two Type 2 AGN. In particular, I will discuss the possibility of strong outflows from an AGN. These outflow phenomena can be an important feedback mechanism in galaxies and are apparently common in AGN, making them a viable alternative to the dual AGN scenario. Based on our candidate's luminosity and emission line intensities, we find that an outflow is a possibility. If this is the case, such an outflow would be especially strong and has implications for AGN feedback in galaxies. However, the dual AGN scenario cannot be ruled out, and at z=1.175, the two putative AGN could potentially be resolved with Chandra. Other candidate dual AGN at similar redshifts and with significant obscuration could also be confirmed this way. This research was sponsored by the Strategic University Research Partnership Program, the National Aeronautics and Space Administration and the Arkansas NASA EPSCoR program.

  20. The responsibilities of engineers.

    Science.gov (United States)

    Smith, Justin; Gardoni, Paolo; Murphy, Colleen

    2014-06-01

    Knowledge of the responsibilities of engineers is the foundation for answering ethical questions about the work of engineers. This paper defines the responsibilities of engineers by considering what constitutes the nature of engineering as a particular form of activity. Specifically, this paper focuses on the ethical responsibilities of engineers qua engineers. Such responsibilities refer to the duties acquired in virtue of being a member of a group. We examine the practice of engineering, drawing on the idea of practices developed by philosopher Alasdair MacIntyre, and show how the idea of a practice is important for identifying and justifying the responsibilities of engineers. To demonstrate the contribution that knowledge of the responsibilities of engineers makes to engineering ethics, a case study from structural engineering is discussed. The discussion of the failure of the Sleipner A Platform off the coast of Norway in 1991 demonstrates how the responsibilities of engineers can be derived from knowledge of the nature of engineering and its context.

  1. Metabolic Engineering X Conference

    Energy Technology Data Exchange (ETDEWEB)

    Flach, Evan [American Institute of Chemical Engineers

    2015-05-07

    The International Metabolic Engineering Society (IMES) and the Society for Biological Engineering (SBE), both technological communities of the American Institute of Chemical Engineers (AIChE), hosted the Metabolic Engineering X Conference (ME-X) on June 15-19, 2014 at the Westin Bayshore in Vancouver, British Columbia. It attracted 395 metabolic engineers from academia, industry and government from around the globe.

  2. Dual model of vocational education: Austrian example

    Directory of Open Access Journals (Sweden)

    Tomić Milica

    2015-01-01

    Full Text Available Dual education, as a form of secondary vocational education means that education and practical training are held on two locations - in school and in a company (organization, factory and that these two institutions jointly participate in the realization of vocational education. The paper presents an account of the functioning of dual education in Austria. In that framework special attention was paid to law regulations in this field, the modes of dual education, progression through the system and the perspectives of the young in the labour market. Among the key features of dual education which are, at the same time, considered the factors of its successfulness, the following stand out: active role of social partners in the conceptualization and realization of vocational education; intensive practical training of high quality; systemic interrelatedness of vocational schools and firms where practical training is provided, the compliance of the offer of educational profiles and the needs of labour market; the system of stimulation for the firms that provide professional training for students, clear legislation and the system of professional qualifications. Yet, the challenges of dual educations are not neglected in the paper.

  3. Dual diagnosis in older adults: a review.

    Science.gov (United States)

    Searby, Adam; Maude, Phil; McGrath, Ian

    2015-02-01

    Dual diagnosis is associated with frequent relapse, poor treatment engagement and overall unsatisfactory treatment outcomes. A comprehensive review of the contemporary literature examining this issue was conducted, finding a paucity of literature concerning dual diagnosis in older adults. Of the literature appraised for this review, a number of studies examined US Veteran's Affairs populations, which were largely male. Studies concerning older mental health populations were scarce. During the literature search, a number of background studies that influenced contemporary research regarding dual diagnosis in older adults were found; these studies were examined regarding their contribution to contemporary paradigms concerning older adults with co-occurring mental illness and substance use disorders. This review presents the results of the contemporary literature concerning dual diagnosis in older adults. Several recurring themes emerge from the literature, including the notion of a statistically small population that, in absolute terms, represents a sizeable number of individuals coming to the attention of aged mental health services in the future. Additionally, the potential for under-diagnosis in this cohort is highlighted, potentially creating a hidden population of older adults with dual diagnosis.

  4. Effect of propulsion system characteristics on ascent performance of dual-fueled single-stage earth-to-orbit transports

    Science.gov (United States)

    Rehder, J. J.

    1977-01-01

    The results of a parametric study of ascent performance are presented for a vertical take off, horizontal landing, single stage earth-to-orbit transport vehicle. Two dual fueled concepts, series burn and parallel burn, were investigated, both of which utilized dual position rocket nozzles. The analysis was made by systematically varying a set of propulsion similarity parameters, initial thrust-weight ratio, the proportion of the thrust due to dual position nozzle engines, expansion ratios of the rocket nozzle, and the relative split between the two fuels, hydrogen and hydrocarbon. The data are presented as a series of curves of mass ratio plotted against each of the similarity parameters for various combinations of the other similarity parameters.

  5. Modeling of hybrid vehicle fuel economy and fuel engine efficiency

    Science.gov (United States)

    Wu, Wei

    "Near-CV" (i.e., near-conventional vehicle) hybrid vehicles, with an internal combustion engine, and a supplementary storage with low-weight, low-energy but high-power capacity, are analyzed. This design avoids the shortcoming of the "near-EV" and the "dual-mode" hybrid vehicles that need a large energy storage system (in terms of energy capacity and weight). The small storage is used to optimize engine energy management and can provide power when needed. The energy advantage of the "near-CV" design is to reduce reliance on the engine at low power, to enable regenerative braking, and to provide good performance with a small engine. The fuel consumption of internal combustion engines, which might be applied to hybrid vehicles, is analyzed by building simple analytical models that reflect the engines' energy loss characteristics. Both diesel and gasoline engines are modeled. The simple analytical models describe engine fuel consumption at any speed and load point by describing the engine's indicated efficiency and friction. The engine's indicated efficiency and heat loss are described in terms of several easy-to-obtain engine parameters, e.g., compression ratio, displacement, bore and stroke. Engine friction is described in terms of parameters obtained by fitting available fuel measurements on several diesel and spark-ignition engines. The engine models developed are shown to conform closely to experimental fuel consumption and motored friction data. A model of the energy use of "near-CV" hybrid vehicles with different storage mechanism is created, based on simple algebraic description of the components. With powertrain downsizing and hybridization, a "near-CV" hybrid vehicle can obtain a factor of approximately two in overall fuel efficiency (mpg) improvement, without considering reductions in the vehicle load.

  6. Sliding Mode Variable Structure Control and Real-Time Optimization of Dry Dual Clutch Transmission during the Vehicle’s Launch

    OpenAIRE

    Zhiguo Zhao; Haijun Chen; Qi Wang

    2014-01-01

    In order to reflect driving intention adequately and improve the launch performance of vehicle equipped with five-speed dry dual clutch transmission (DCT), the issue of coordinating control between engine and clutch is researched, which is based on the DCT and prototype car developed independently. Four-degree-of-freedom (DOF) launch dynamics equations are established. Taking advantage of predictive control and genetic algorithm, target tracing curves of engine speed and vehicle velocity are ...

  7. Engineer named Loring Professor

    OpenAIRE

    Nystrom, Lynn A.

    2005-01-01

    Saifur Rahman, Virginia Tech professor of electrical and computer engineering (ECE) and the founding director of Virginia Tech's Northern Virginia Division of the College of Engineering, is the recipient of the Joseph R. Loring Professorship of Electrical and Computer Engineering.

  8. Effect of vortex formation on sediment transport at dual pipe intakes

    Indian Academy of Sciences (India)

    M R KHANARMUEI; H RAHIMZADEH; A R KAKUEI; H SARKARDEH

    2016-09-01

    Vortex formation and subsequent sediment transport into the intake due to sea water withdrawal is one of the problems in coastal engineering. The effect of vortex formation on rate of sediment transport at coastal dual pipe intakes was investigated using a scaled physical model. Experiments were performed on dual pipe intakes at three common intake withdrawal directions (vertical, horizontal and with angle of 45°). In eachexperiment, the class of vortex with respect to its strength was determined. Particle tracking velocimetry (PTV) was employed to measure tangential velocity of vortices. Results indicated that the rate of sediment transport was considerably affected by the strength of formed vortices. The rate of transported sediment was increased by increasing the strength of formed vortex. Moreover, amount of sediment transport was affected by angle of pipe intakes. It could be concluded that the minimum and maximum rates of sediment transport occur for inclined and horizontal intakes, respectively.

  9. Mod II engine development

    Science.gov (United States)

    Karl, David W.

    1987-01-01

    The Mod II engine, a four-cylinder, automotive Stirling engine utilizing the Siemens-Rinia double-acting concept, was assembled and became operational in January 1986. This paper describes the Mod II engine, its first assembly, and the subsequent development work done on engine components up to the point that engine performance characterization testing took place. Performance data for the engine are included.

  10. What is the dual of a dipole?

    Energy Technology Data Exchange (ETDEWEB)

    Alday, Luis F. [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, 3508 TD Utrecht (Netherlands)]. E-mail: l.f.alday@phys.uu.nl; Boer, Jan de [Instituut voor Theoretische Fysica, Valckenierstraat 65, 1018 XE Amsterdam (Netherlands)]. E-mail: jdeboer@science.uva.nl; Messamah, Ilies [Instituut voor Theoretische Fysica, Valckenierstraat 65, 1018 XE Amsterdam (Netherlands)]. E-mail: imessama@science.uva.nl

    2006-07-03

    We study gravitational solutions that admit a dual CFT description and carry non-zero dipole charge. We focus on the black ring solution in AdS{sub 3}xS{sup 3} and extract from it the one-point functions of all CFT operators dual to scalar excitations of the six-dimensional metric. In the case of small black rings, characterized by the level N, angular momentum J and dipole charge q{sub 3}, we show how the large N and J dependence of the one-point functions can be reproduced, under certain assumptions, directly from a suitable ensemble in the dual CFT. Finally we present a simple toy model that describes the thermodynamics of the small black ring for arbitrary values of the dipole charge.

  11. Dual-core antiresonant hollow core fibers.

    Science.gov (United States)

    Liu, Xuesong; Fan, Zhongwei; Shi, Zhaohui; Ma, Yunfeng; Yu, Jin; Zhang, Jing

    2016-07-25

    In this work, dual-core antiresonant hollow core fibers (AR-HCFs) are numerically demonstrated, based on our knowledge, for the first time. Two fiber structures are proposed. One is a composite of two single-core nested nodeless AR-HCFs, exhibiting low confinement loss and a circular mode profile in each core. The other has a relatively simple structure, with a whole elliptical outer jacket, presenting a uniform and wide transmission band. The modal couplings of the dual-core AR-HCFs rely on a unique mechanism that transfers power through the air. The core separation and the gap between the two cores influence the modal coupling strength. With proper designs, both of the dual-core fibers can have low phase birefringence and short modal coupling lengths of several centimeters.

  12. Training Changes Professionals’ Attitudes Towards Dual Diagnosis

    DEFF Research Database (Denmark)

    Pinderup, Pernille

    2016-01-01

    and treatment outcome. This study tested whether providing training in dual diagnosis treatment to mental health professionals will affect their attitudes positively. Twenty-one professionals completed a questionnaire on attitudes towards working with dual diagnosis (Comorbidity Problems Perceptions......Studies have shown that mental health professionals in many cases have counterproductive attitudes towards patients with mental illnesses and comorbid substance use disorders (dual diagnosis). This is problematic because professionals’ attitudes are important for both the therapeutic alliance...... Questionnaire, CMPPQ) pre-training and post-training. Results showed that there was a significant positive change in total CMPPQ scores and a positive change in all six subscales of the CMPPQ following training, indicating that the training resulted in more positive attitudes. The study suggests that training...

  13. Transition-Aged Youths With Dual Diagnoses.

    Science.gov (United States)

    Kalinyak, Christopher M; Gary, Faye A; Killion, Cheryl M; Suresky, M Jane

    2016-03-01

    The current study provides an overview of the research knowledge about unique problems encountered by transition-aged youths with dual diagnoses. A description of the considerable physical and emotional changes experienced by transition-aged youths provides a foundation for exploring the pressures and challenges compounded by mental health issues and substance abuse. Programs that provide intensive support throughout the transition years pay valuable dividends. However, transition-aged youths with dual diagnoses of mental disorders and substance abuse find themselves faced with limited or nonexistent options. There is a confusing lack of continuity and consistency of supports and services, which complicates the already perplexing circumstances that beleaguer the lives of young adults with dual diagnoses. Copyright 2016, SLACK Incorporated.

  14. PADDLE: Proximal Algorithm for Dual Dictionaries LEarning

    CERN Document Server

    Basso, Curzio; Verri, Alessandro; Villa, Silvia

    2010-01-01

    Recently, considerable research efforts have been devoted to the design of methods to learn from data overcomplete dictionaries for sparse coding. However, learned dictionaries require the solution of an optimization problem for coding new data. In order to overcome this drawback, we propose an algorithm aimed at learning both a dictionary and its dual: a linear mapping directly performing the coding. By leveraging on proximal methods, our algorithm jointly minimizes the reconstruction error of the dictionary and the coding error of its dual; the sparsity of the representation is induced by an $\\ell_1$-based penalty on its coefficients. The results obtained on synthetic data and real images show that the algorithm is capable of recovering the expected dictionaries. Furthermore, on a benchmark dataset, we show that the image features obtained from the dual matrix yield state-of-the-art classification performance while being much less computational intensive.

  15. A dual approach to IS strategy

    DEFF Research Database (Denmark)

    Ivang, Reimer

    2014-01-01

    This paper discusses IS strategising and how the combination of the planning and the incremental approaches can enable successful IS strategising. IS strategising is conceptualised as a dual organisational process in which the network and the hierarchy positively coexist through group......-learning processes. The findings from two case studies illustrate the theoretical framework. An analysis of 28 interviews reveal the complexity of IS strategising and show that IS strategising is best understood as a dual dynamic-interactive processing which the choice of strategic approach is not a dichotomy...... but more of a both/and decision. The overall conclusion is that IS strategy, because of increased uncertainty and environmental complexity, must encourage interaction between key stakeholders who implement and use the IS technology. The dual organisation and the experience-based group-learning processes...

  16. Self-dual gravity with topological terms

    CERN Document Server

    Montesinos, M

    2001-01-01

    The canonical analysis of the (anti-) self-dual action for gravity supplemented with the (anti-) self-dual Pontrjagin term is carried out. The effect of the topological term is to add a `magnetic' term to the original momentum variable associated with the self-dual action leaving the Ashtekar connection unmodified. In the new variables, the Gauss constraint retains its form, while both vector and Hamiltonian constraints are modified. This shows, the contribution of the Euler and Pontrjagin terms is not the same as that coming from the term associated with the Barbero-Immirzi parameter, and thus the analogy between the theta-angle in Yang-Mills theory and the Barbero-Immirzi parameter of gravity is not appropriate.

  17. What is the dual of a dipole?

    CERN Document Server

    Alday, L F; Messamah, I; Alday, Luis F.; Boer, Jan de; Messamah, Ilies

    2006-01-01

    We study gravitational solutions that admit a dual CFT description and carry non zero dipole charge. We focus on the black ring solution in AdS_3 x S^3 and extract from it the one-point functions of all CFT operators dual to scalar excitations of the six-dimensional metric. In the case of small black rings, characterized by the level N, angular momentum J and dipole charge q_3, we show how the large N and J dependence of the one-point functions can be reproduced, under certain assumptions, directly from a suitable ensemble in the dual CFT. Finally we present a simple toy model that describes the thermodynamics of the small black ring for arbitrary values of the dipole charge.

  18. Dual condensates at finite isospin chemical potential

    CERN Document Server

    Zhang, Zhao

    2015-01-01

    The dual observables as order parameters for center symmetry are tested at finite isospin chemical potential $\\mu_I$ in a Polyakov-loop enhanced chiral model of QCD with physical quark masses. As a counterpart of the dressed Polyakov-loop, the first Fourier moment of pion condensate is introduced for $\\mu_I>{m_\\pi}/{2}$ under the temporal twisted boundary conditions for quarks. We demonstrate that this dual condensate exhibits the similar temperature dependence as the conventional Polyakov-loop. We confirm that its rapid increase with $T$ is driven by the evaporating of pion condensation. On the other hand, the dressed Polyakov-loop shows abnormal thermal behavior, which even decreases with $T$ at low temperatures due to the influence of pion condensate. We thus argue that in QCD the critical temperature extracting from a dual observable may have nothing to do with the quark confinement-deconfinement transition if the quark mass is very small.

  19. Comments on the dual-BRST symmetry

    CERN Document Server

    Krishna, S; Malik, R P

    2011-01-01

    In view of a raging controversy on the topic of dual-Becchi-Rouet-Stora-Tyutin (dual-BRST/co-BRST) and anti-co-BRST symmetry transformations in the context of four (3+1)-dimensional (4D) Abelian 2-form and 2D (non-)Abelian 1-form gauge theories, we attempt, in our present short note, to settle the dust by taking the help of mathematics of differential geometry, connected with the Hodge theory, which was the original motivation for the nomenclature of dual-BRST symmetry in our earlier set of works. It has been claimed, in a recent set of papers, that the co-BRST symmetries are not independent of BRST symmetries. We show that the BRST and co-BRST symmetries are independent symmetries in the same fashion as the exterior and co-exterior derivatives are independent entities belonging to the set of de Rham cohomological operators of differential geometry.

  20. Ultrafast electrooptic dual-comb interferometry

    CERN Document Server

    Duran, Vicente; Torres-Company, Victor

    2015-01-01

    The femtosecond laser frequency comb has enabled the 21st century revolution in optical synthesis and metrology. A particularly compelling technique that relies on the broadband coherence of two laser frequency combs is dual-comb interferometry. This method is rapidly advancing the field of optical spectroscopy and empowering new applications, from nonlinear microscopy to laser ranging. Up to now, most dual-comb interferometers were based on modelocked lasers, whose repetition rates have restricted the measurement speed to ~ kHz. Here we demonstrate a novel dual-comb interferometer that is based on electrooptic frequency comb technology and measures consecutive complex spectra at a record-high refresh rate of 25 MHz. These results pave the way for novel scientific and metrology applications of frequency comb generators beyond the realm of molecular spectroscopy, where the measurement of ultrabroadband waveforms is of paramount relevance.

  1. Modular Engineering Concept at Novo Nordisk Engineering

    DEFF Research Database (Denmark)

    Moelgaard, Gert; Miller, Thomas Dedenroth

    1997-01-01

    This report describes the concept of a new engineering method at Novo Nordisk Engineering: Modular Engineering (ME). Three tools are designed to support project phases with different levels of detailing and abstraction. ME supports a standard, cross-functional breakdown of projects that facilitates...

  2. Modular Engineering Concept at Novo Nordisk Engineering

    DEFF Research Database (Denmark)

    Moelgaard, Gert; Miller, Thomas Dedenroth

    1997-01-01

    This report describes the concept of a new engineering method at Novo Nordisk Engineering: Modular Engineering (ME). Three tools are designed to support project phases with different levels of detailing and abstraction. ME supports a standard, cross-functional breakdown of projects that facilitates...

  3. Environmental Engineering in Mining Engineering Education

    Science.gov (United States)

    Mahamud-Lopez, Manuel Maria; Menendez-Aguado, Juan Maria

    2005-01-01

    In this paper, the current profile of the environmental engineer and the programming of the subject "Environmental Engineering and Technology" corresponding to the studies of Mining Engineering at the University of Oviedo in Spain, is discussed. Professional profile, student knowledge prior to and following instruction as well as…

  4. Software engineering as an engineering discipline

    Science.gov (United States)

    Freedman, Glenn B.

    1988-01-01

    The purpose of this panel is to explore the emerging field of software engineering from a variety of perspectives: university programs; industry training and definition; government development; and technology transfer. In doing this, the panel will address the issues of distinctions among software engineering, computer science, and computer hardware engineering as they relate to the challenges of large, complex systems.

  5. Engineering Encounters: Blasting off with Engineering

    Science.gov (United States)

    Dare, Emily A.; Childs, Gregory T.; Cannaday, E. Ashley; Roehrig, Gillian H

    2014-01-01

    What better way to engage young students in physical science concepts than to have them engineer flying toy rockets? The integration of engineering into science classrooms is advocated by the "Next Generation Science Standards" (NGSS) and researchers alike (Brophy et al. 2008), as engineering provides: (1) A "real-world…

  6. Semi-empirical model to evaluate the performance of natural gas powered diesel engines; Modelo semi-empirico para avaliacao do desempenho de motores diesel consumindo gas natural

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Ricardo Hernandez [Universidade Federal de Uberlandia (UFU), MG (Brazil). Faculdade de Engenharia Mecanica], e-mail: ricardo.pereira@mecanica.ufu.br; Braga, Carlos Valois Maciel; Braga, Sergio Leal [Pontificia Universidade Catolica do Rio de Janeiro (DEM/PUC-Rio), RJ (Brazil). Dept. de Engenharia Mecanica], e-mails: valois@puc-rio.br, slbraga@puc-rio.br

    2010-04-15

    The performance of four different engines were measured, all powered by the dual fuels diesel/natural gas and mounted on a dynamometer bench. The tested engines were selected for their construction and operational characteristics, representing diesel engines for different applications (capacity, speed range, with/without turbo charging and combustion air cooling). Experimental points were obtained for wide parameter ranges with influence on engine performance. The replacement rate of diesel with natural gas was varied to identify the mix where the dual fuel operation was possible. Although the study focus was on performance, data on particulate pollutant emissions were also recorded, not only during the original diesel operation but also for the dual fuels. The results indicate that, for most operational fields of the engines tested, only part of the gas actually burns. (author)

  7. Engine Test Facility (ETF)

    Data.gov (United States)

    Federal Laboratory Consortium — The Air Force Arnold Engineering Development Center's Engine Test Facility (ETF) test cells are used for development and evaluation testing of propulsion systems for...

  8. Contemporary engineering economics

    CERN Document Server

    Park, Chan S

    2011-01-01

    Contemporary Engineering Economics, 5/e, is intended for undergraduate engineering students taking introductory engineering economics while appealing to the full range of engineering disciplines for which this course is often required: industrial, civil, mechanical, electrical, computer, aerospace, chemical, and manufacturing engineering, as well as engineering technology. This edition has been thoroughly revised and updated while continuing to adopt a contemporary approach to the subject, and teaching, of engineering economics. This text aims not only to build a sound and comprehensive coverage of engineering economics, but also to address key educational challenges, such as student difficulty in developing the analytical skills required to make informed financial decisions.

  9. Advanced Metasearch Engine Technology

    CERN Document Server

    Meng, Weiyi

    2010-01-01

    Among the search tools currently on the Web, search engines are the most well known thanks to the popularity of major search engines such as Google and Yahoo!. While extremely successful, these major search engines do have serious limitations. This book introduces large-scale metasearch engine technology, which has the potential to overcome the limitations of the major search engines. Essentially, a metasearch engine is a search system that supports unified access to multiple existing search engines by passing the queries it receives to its component search engines and aggregating the returned

  10. Dual-support Smoothed Particle Hydrodynamics

    CERN Document Server

    Ren, Huilong; Zhuang, Xiaoying; Rabczuk, Timon

    2016-01-01

    In this paper we develop a dual-support smoothed particle hydrodynamics (DS-SPH) that naturally satisfies the conservation of momentum, angular momentum and energy when the varying smoothing length is utilized. The DS-SPH is based on the concept of dual-support, which is introduced to consider the unbalanced interactions between the particles with different smoothing lengths. Our DS-SPH formulation can be implemented in traditional SPH with little changes and improve the computational efficiency. Several numerical examples are presented to demonstrate the capability of the method.

  11. Integrable Deformations of T -Dual σ Models

    Science.gov (United States)

    Borsato, Riccardo; Wulff, Linus

    2016-12-01

    We present a method to deform (generically non-Abelian) T duals of two-dimensional σ models, which preserves classical integrability. The deformed models are identified by a linear operator ω on the dualized subalgebra, which satisfies the 2-cocycle condition. We prove that the so-called homogeneous Yang-Baxter deformations are equivalent, via a field redefinition, to our deformed models when ω is invertible. We explain the details for deformations of T duals of principal chiral models, and present the corresponding generalization to the case of supercoset models.

  12. Dual waveband compact catadioptric imaging spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Chrisp, Michael P.

    2012-12-25

    A catadioptric dual waveband imaging spectrometer that covers the visible through short-wave infrared, and the midwave infrared spectral regions, dispersing the visible through shortwave infrared with a zinc selenide grating and midwave infrared with a sapphire prism. The grating and prism are at the cold stop position, enabling the pupil to be split between them. The spectra for both wavebands are focused onto the relevant sections of a single dual waveband detector. Spatial keystone distortion is controlled to less than one tenth of a pixel over the full wavelength range, facilitating the matching of the spectra in the midwave infrared with the shorter wavelength region.

  13. Dual (type IV left anterior descending artery

    Directory of Open Access Journals (Sweden)

    Ozdil Baskan

    2013-11-01

    Full Text Available Congenital coronary artery anomalies are uncommon. Dual left anterior descending coronary artery (LAD is defined as the presence of two LADs within the anterior interventricular sulcus (AIVS, and is classified into four types. Type IV is a rarely reported subtype and differs from the others, with a long LAD originating from the right coronary artery (RCA. Dual LAD is a benign coronary artery anomaly, but should be recognised especially before interventional procedures. With the increasing use of multidedector computed tomography (MDCT, it is essential for radiologists to be aware of this entity and the cross-sectional findings.

  14. Dual Axis Light Sensor for Tracking Sun

    Science.gov (United States)

    Shibata, Miki; Tambo, Toyokazu

    We have developed convenient light sensors to control a platform of solar cell panel. Dual axis light sensor in the present paper has structure of 5 PD (photodiode) light sensor which is composed of 5 photodiodes attached on a frustum of pyramid(1). Light source can be captured in front of the sensor by rotating the X and Y axis as decreasing the output deviation between two pairs of outside photodiodes. We here report the mechanism of sun tacking using the dual axis 5 PD light sensor and the fundamental results performed in the dark room.

  15. Dual Causality and the Autonomy of Biology.

    Science.gov (United States)

    Bock, Walter J

    2017-03-01

    Ernst Mayr's concept of dual causality in biology with the two forms of causes (proximate and ultimate) continues to provide an essential foundation for the philosophy of biology. They are equivalent to functional (=proximate) and evolutionary (=ultimate) causes with both required for full biological explanations. The natural sciences can be classified into nomological, historical nomological and historical dual causality, the last including only biology. Because evolutionary causality is unique to biology and must be included for all complete biological explanations, biology is autonomous from the physical sciences.

  16. Cascaded uncoupled dual-ring modulator

    CERN Document Server

    Gu, Tingyi; Wong, Chee Wei; Dong, Po

    2014-01-01

    We demonstrate that by coherent driving two uncoupled rings in same direction, the effective photon circulating time in the dual ring modulator is reduced, with increased modulation quality. The inter-ring detuning dependent photon dynamics, Q-factor, extinction ratio and optical modulation amplitude of two cascaded silicon ring resonators are studied and compared with that of a single ring modulator. Experimentally measured eye diagrams, together with coupled mode theory simulations, demonstrate the enhancement of dual ring configuration at 20 Gbps with a Q ~ 20,000.

  17. Community engagement research and dual diagnosis anonymous.

    Science.gov (United States)

    Roush, Sean; Monica, Corbett; Pavlovich, Danny; Drake, Robert E

    2015-01-01

    Community engagement research is widely discussed but rarely implemented. This article describes the implementation of a community engagement research project on Dual Diagnosis Anonymous, a rapidly spreading peer support program in Oregon for people with co-occurring mental illness and substance use disorders. After three years of discussions, overcoming barriers, and involving several institutions, this grassroots research project has been implemented and is expanding. Active participants in Dual Diagnosis Anonymous inspired and instructed policy makers, professionals, and students. Community engagement research requires frontline participants, community members, and professional collaborators to overcome multiple barriers with persistence and steadfastness. Building trust, collaboration, and structures for community engagement research takes time and a community effort.

  18. Gap Model for Dual Customer Values

    Institute of Scientific and Technical Information of China (English)

    HOU Lun; TANG Xiaowo

    2008-01-01

    The customer value, the key problem in customer relationship management (CRM), was studied to construct a gap model for dual customer values. A basic description of customer values is given, and then the gaps between products and services in different periods for the customers and companies are analyzed based on the product or service life-cycle. The main factors that influence the perceived customer value were analyzed to define the "recognized value gap" and a gap model for the dual customer values was constructed to supply companies with a tool to analyze existing customer value gaps and improve customer relationship management.

  19. Toward a Gravity Dual of Glueball Inflation

    CERN Document Server

    Anguelova, Lilia; Wijewardhana, L C Rohana

    2015-01-01

    We summarize and extend our work on nonsupersymmetric solutions of a 5d consistent truncation of type IIB supergravity, that is relevant for gauge/gravity duality. The fields in this 5d theory are the five-dimensional metric and a set of scalars. We find solutions of the 5d equations of motion, which represent dS_4 foliations over the fifth (radial) dimension. In each solution at least one scalar has a nontrivial radial profile. These scalars are interpreted as glueballs in the dual gauge theory, living in 4d de Sitter space. We explain why this lays a foundation for building gravity duals of glueball inflation models.

  20. Dual Superconductivity in G2 group

    CERN Document Server

    Cossu, G; Di Giacomo, Adriano; Lucini, B; Pica, C

    2006-01-01

    We investigate the dual superconductivity mechanism in the exceptional group $G_2$. This is a centerless group (no 't Hooft flux vortices are allowed) and we check for the presence of a magnetic monopole condensate in the confined phase by measuring on the lattice a disorder parameter related to the vacuum expectation value of an operator carrying magnetic charge. The behaviour of the disorder parameter is consistent with the dual superconductor picture. A first step of an analysis on the thermodynamical properties of the theory is conducted by mean of this operator.

  1. Dual diagnosis among physicians: a clinical perspective.

    Science.gov (United States)

    Braquehais, María Dolores; Lusilla, Pilar; Bel, Miquel Jordi; Navarro, María Cecilia; Nasillo, Viviana; Díaz, Albert; Valero, Sergi; Padrós, Jaume; Bruguera, Eugeni; Casas, Miquel

    2014-01-01

    Co-occurrence of mental disorders and substance use disorders (dual diagnosis) among doctors is a cause of serious concern due to its negative personal, professional, and social consequences. This work provides an overview of the prevalence of dual diagnosis among physicians, suggests a clinical etiological model to explain the development of dual diagnosis in doctors, and recommends some treatment strategies specifically for doctors. The most common presentation of dual diagnosis among doctors is the combination of alcohol use disorders and affective disorders. There are also high rates of self-medication with benzodiazepines, legal opiates, and amphetamines compared to the general population, and cannabis use disorders are increasing, mainly in young doctors. The prevalence of nicotine dependence varies from one country to another depending on the nature of public health policies. Emergency medicine physicians, psychiatrists, and anaesthesiologists are at higher risk for developing a substance use disorder compared with other doctors, perhaps because of their knowledge of and access to certain legal drugs. Two main pathways may lead doctors toward dual diagnosis: (a) the use of substances (often alcohol or self-prescribed drugs) as an unhealthy strategy to cope with their emotional or mental distress and (b) the use of substances for recreational or other purposes. In both cases, doctors tend to delay seeking help once a problem has been established, often for many years. Denial, minimization, and rationalization are common defense mechanisms, maybe because of the social stigma associated with mental or substance use disorders, the risk of losing employment/medical license, and a professional culture of perfectionism and denial of emotional needs or failures. Personal vulnerability interacts with these factors to increase the risk of a dual diagnosis developing in some individuals. When doctors with substance use disorders accept treatment in programs

  2. Unraveling Executive Functioning in Dual Diagnosis

    OpenAIRE

    Duijkers, J.C.L.M.; Vissers, C.T.W.M.; Egger, J. I. M.

    2016-01-01

    In mental health, the term dual-diagnosis is used for the co-occurrence of Substance Use Disorder (SUD) with another mental disorder. These co-occurring disorders can have a shared cause, and can cause/intensify each other's expression. Forming a threat to health and society, dual-diagnosis is associated with relapses in addiction-related behavior and a destructive lifestyle. This is due to a persistent failure to control impulses and the maintaining of inadequate self-regulatory behavior in ...

  3. One-to-six WDM multicasting of DPSK signals based on dual-pump four-wave mixing in a silicon waveguide

    DEFF Research Database (Denmark)

    Pu, Minhao; Hu, Hao; Ji, Hua

    2011-01-01

    We present WDM multicasting based on dual-pump four-wave mixing in a 3-mm long dispersion engineered silicon waveguide. One-to-six phase-preserving WDM multicasting of 10-Gb/s differential phase-shiftkeying (DPSK) data is experimentally demonstrated with bit-error rate measurements. All the six...

  4. ON THE THREAT OF SUPPLIERS FOR THE ENGINEERING CONSULTING AND DESIGN SERVICES FIRMS

    Directory of Open Access Journals (Sweden)

    Gabriel Sorin STROE

    2014-06-01

    Full Text Available In the case of companies from engineering consulting and design services industry the classic models of analysis (e.g. Porter's five forces for structural analysis exhibit interesting aspects in comparison with the situation when applied to traditional services or industrial production firms, due to the distinctive characteristics of the industry. The purpose of this paper is to present a general overview of the engineering consulting and design industry also analyze different facets of the suppliers concept and their force and threat for the engineering services firms. The paper aims at analyzing the dual strategic role of aspecial type of suppliers for the engineering companies.

  5. Using Collaborative Engineering to Inform Collaboration Engineering

    Science.gov (United States)

    Cooper, Lynne P.

    2012-01-01

    Collaboration is a critical competency for modern organizations as they struggle to compete in an increasingly complex, global environment. A large body of research on collaboration in the workplace focuses both on teams, investigating how groups use teamwork to perform their task work, and on the use of information systems to support team processes ("collaboration engineering"). This research essay presents collaboration from an engineering perspective ("collaborative engineering"). It uses examples from professional and student engineering teams to illustrate key differences in collaborative versus collaboration engineering and investigates how challenges in the former can inform opportunities for the latter.

  6. Using Collaborative Engineering to Inform Collaboration Engineering

    Science.gov (United States)

    Cooper, Lynne P.

    2012-01-01

    Collaboration is a critical competency for modern organizations as they struggle to compete in an increasingly complex, global environment. A large body of research on collaboration in the workplace focuses both on teams, investigating how groups use teamwork to perform their task work, and on the use of information systems to support team processes ("collaboration engineering"). This research essay presents collaboration from an engineering perspective ("collaborative engineering"). It uses examples from professional and student engineering teams to illustrate key differences in collaborative versus collaboration engineering and investigates how challenges in the former can inform opportunities for the latter.

  7. Genome scale engineering techniques for metabolic engineering.

    Science.gov (United States)

    Liu, Rongming; Bassalo, Marcelo C; Zeitoun, Ramsey I; Gill, Ryan T

    2015-11-01

    Metabolic engineering has expanded from a focus on designs requiring a small number of genetic modifications to increasingly complex designs driven by advances in genome-scale engineering technologies. Metabolic engineering has been generally defined by the use of iterative cycles of rational genome modifications, strain analysis and characterization, and a synthesis step that fuels additional hypothesis generation. This cycle mirrors the Design-Build-Test-Learn cycle followed throughout various engineering fields that has recently become a defining aspect of synthetic biology. This review will attempt to summarize recent genome-scale design, build, test, and learn technologies and relate their use to a range of metabolic engineering applications.

  8. Thrust Area Report, Engineering Research, Development and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Langland, R. T.

    1997-02-01

    The mission of the Engineering Research, Development, and Technology Program at Lawrence Livermore National Laboratory (LLNL) is to develop the knowledge base, process technologies, specialized equipment, tools and facilities to support current and future LLNL programs. Engineering`s efforts are guided by a strategy that results in dual benefit: first, in support of Department of Energy missions, such as national security through nuclear deterrence; and second, in enhancing the nation`s economic competitiveness through our collaboration with U.S. industry in pursuit of the most cost- effective engineering solutions to LLNL programs. To accomplish this mission, the Engineering Research, Development, and Technology Program has two important goals: (1) identify key technologies relevant to LLNL programs where we can establish unique competencies, and (2) conduct high-quality research and development to enhance our capabilities and establish ourselves as the world leaders in these technologies. To focus Engineering`s efforts technology {ital thrust areas} are identified and technical leaders are selected for each area. The thrust areas are comprised of integrated engineering activities, staffed by personnel from the nine electronics and mechanical engineering divisions, and from other LLNL organizations. This annual report, organized by thrust area, describes Engineering`s activities for fiscal year 1996. The report provides timely summaries of objectives, methods, and key results from eight thrust areas: Computational Electronics and Electromagnetics; Computational Mechanics; Microtechnology; Manufacturing Technology; Materials Science and Engineering; Power Conversion Technologies; Nondestructive Evaluation; and Information Engineering. Readers desiring more information are encouraged to contact the individual thrust area leaders or authors. 198 refs., 206 figs., 16 tabs.

  9. The dual of a generalized minimax location problem

    DEFF Research Database (Denmark)

    Juel, Henrik; Love, Robert F.

    1992-01-01

    This paper develops the dual formulation of a generalized minimax facility location problem which has distance and linear constraints......This paper develops the dual formulation of a generalized minimax facility location problem which has distance and linear constraints...

  10. The dual of a generalized minimax location problem

    DEFF Research Database (Denmark)

    Juel, Henrik; Love, Robert F.

    1992-01-01

    This paper develops the dual formulation of a generalized minimax facility location problem which has distance and linear constraints......This paper develops the dual formulation of a generalized minimax facility location problem which has distance and linear constraints...

  11. [Research of dual-photoelastic-modulator-based beat frequency modulation and Fourier-Bessel transform imaging spectrometer].

    Science.gov (United States)

    Wang, Zhi-Bin; Zhang, Rui; Wang, Yao-Li; Huang, Yan-Fei; Chen, You-Hua; Wang, Li-Fu; Yang, Qiang

    2014-02-01

    As the existing photoelastic-modulator(PEM) modulating frequency in the tens of kHz to hundreds of kHz between, leading to frequency of modulated interference signal is higher, so ordinary array detector cannot effectively caprure interference signal..A new beat frequency modulation method based on dual-photoelastic-modulator (Dual-PEM) and Fourier-Bessel transform is proposed as an key component of dual-photoelastic-modulator-based imaging spectrometer (Dual-PEM-IS) combined with charge coupled device (CCD). The dual-PEM are operated as an electro-optic circular retardance modulator, Operating the PEMs at slightly different resonant frequencies w1 and w2 respectively, generates a differential signal at a much lower heterodyne frequency that modulates the incident light. This method not only retains the advantages of the existing PEM, but also the frequency of modulated photocurrent decreased by 2-3 orders of magnitude (10-500 Hz) and can be detected by common array detector, and the incident light spectra can be obtained by Fourier-Bessel transform of low frequency component in the modulated signal. The method makes the PEM has the dual capability of imaging and spectral measurement. The basic principle is introduced, the basic equations is derived, and the feasibility is verified through the corresponding numerical simulation and experiment. This method has' potential applications in imaging spectrometer technology, and analysis of the effect of deviation of the optical path difference. This work provides the necessary theoretical basis for remote sensing of new Dual-PEM-IS and for engineering implementation of spectra inversion.

  12. Space Shuttle OMS engine valve technology. [Orbital Maneuvering System

    Science.gov (United States)

    Wichmann, H.

    1974-01-01

    Valve technology program to determine shutoff valve concepts suitable for the Orbital Maneuvering System (OMS) engine of the Space Shuttle. The tradeoff studies selected the electric torque motor operated dual poppet and ball valves as the most desirable valve concepts for the OMS Engine Shutoff Valve. A prototype of one of these concepts was built and subjected to a design verification program. A number of unique features were designed to include the required contamination insensitivity, operating fluid compatibility, decontamination capability, minimum maintenance requirement and long service life capability.

  13. Alcohol & drug abuse: Dual Diagnosis Anonymous of Oregon.

    Science.gov (United States)

    Monica, Corbett; Nikkel, Robert E; Drake, Robert E

    2010-08-01

    Many people with addictions report that support from peer groups fosters recovery. For people with co-occurring mental illnesses, dual-diagnosis peer support groups are considered helpful, but they are often unavailable. Recently, Dual Diagnosis Anonymous peer support groups have spread widely throughout Oregon as a complement to integrated dual diagnosis treatments. This column describes Dual Diagnosis Anonymous and its rapid implementation in Oregon.

  14. Population thinking and natural selection in dual-inheritance theory

    OpenAIRE

    Houkes, WN Wybo

    2012-01-01

    A deflationary perspective on theories of cultural evolution, in particular dual-inheritance theory, has recently been proposed by Lewens. On this ‘pop-culture’ analysis, dual-inheritance theorists apply population thinking to cultural phenomena, without claiming that cultural items evolve by natural selection. This paper argues against this pop-culture analysis of dual-inheritance theory. First, it focuses on recent dual-inheritance models of specific patterns of cultural change. These model...

  15. TESTING OF THE DUAL ROTARY FILTER SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Herman, D.; Fowley, M.; Stefanko, D.

    2011-08-29

    The Savannah River National Laboratory (SRNL) installed and tested two hydraulically connected SpinTek rotary microfilter (RMF) units to determine the behavior of a multiple filter system. Both units were successfully controlled by a control scheme written in DELTA-V architecture by Savannah River Remediation (SRR) Process Control Engineering personnel. The control system was tuned to provide satisfactory response to changing conditions during the operation of the multi-filter system. Stability was maintained through the startup and shutdown of one of the filter units while the second was still in operation. The installation configuration originally proposed by the Small Colum Ion Exchange (SCIX) project of independent filter and motor mountings may be susceptible to vibration. Significant stiffening of the filter and motor mounts was required to minimize the vibration. Alignment of the motor to the filter was a challenge in this test configuration. The deployment configuration must be easy to manipulate and allow for fine adjustment. An analysis of the vibration signature of the test system identified critical speeds. Whether it corresponds to the resonance frequency of a rotor radial vibration mode that was excited by rotor unbalance is uncertain based upon the measurements. A relative motion series should be completed on the filter with the final shaft configuration to determine if the resonances exist in the final filter design. The instrumentation selected for deployment, including the concentrate discharge control valve and flow meters, performed well. Automation of the valve control integrated well with the control scheme and when used in concert with the other control variables, allowed automated control of the dual RMF system. The one area of concern with the instrumentation was the condition resulting when the filtrate flow meter operated with less than three gpm. This low flow was at the lower range of performance for the flow meter. This should not be

  16. Boronate-Phenolic Network Capsules with Dual Response to Acidic pH and cis-Diols.

    Science.gov (United States)

    Guo, Junling; Sun, Huanli; Alt, Karen; Tardy, Blaise L; Richardson, Joseph J; Suma, Tomoya; Ejima, Hirotaka; Cui, Jiwei; Hagemeyer, Christoph E; Caruso, Frank

    2015-08-26

    Dual-responsive boronate-phenolic network (BPN) capsules are fabricated by the complexation of phenylborate and phenolic materials. The BPN capsules are stable in the presence of competing carbohydrates, but dissociate at acidic pH or in the presence of competing cis-diols at physiological pH. This engineered capsule system provides a platform for a wide range of biological and biomedical applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. A Low-Profile Dual-Band Micro-strip Antenna Having Open-Circuited Strip-line-Stub

    OpenAIRE

    長谷川, 孝明; 羽石, 操

    1986-01-01

    Copyright notice. c1986 IEICE All rights reserved. "A Low-Profile Dual-Band Micro-strip Antenna Having Open-Circuited Strip-line-Stub"Misao HANEISHI, Hidekazu SUGA, Takaaki HASEGAWA.The Transactions of the Institute of Electronics and Communication Engineers of Japan. Section E, English, 1986. Vol. E69 No.11 pp. 1165-1166 許諾No.07RB0055.

  18. 14 CFR 23.399 - Dual control system.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Dual control system. 23.399 Section 23.399... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Structure Control Surface and System Loads § 23.399 Dual control system. (a) Each dual control system must be designed to withstand the...

  19. 14 CFR 25.399 - Dual control system.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Dual control system. 25.399 Section 25.399... STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.399 Dual control system. (a) Each dual control system must be designed for the pilots operating in opposition,...

  20. 14 CFR 29.399 - Dual control system.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Dual control system. 29.399 Section 29.399... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Control Surface and System Loads § 29.399 Dual control system. Each dual primary flight control system must be able to withstand the loads that...