WorldWideScience

Sample records for cooler reflective streets

  1. Examples of cooler reflective streets for urban heat-island mitigation : Portland cement concrete and chip seals

    Energy Technology Data Exchange (ETDEWEB)

    Pomerantz, M.; Akbari, H.; Chang, S.-C.; Levinson, R.; Pon, B.

    2003-04-30

    Part of the urban heat island effect can be attributed to dark pavements that are commonly used on streets and parking lots. In this paper we consider two light colored, hence cooler, alternative paving materials that are in actual use in cities today. These are Portland cement concrete (PCC) pavements and chip seals. We report measurements of the albedos of some PCC and chip sealed pavements in the San Francisco Bay Area. The albedos of the PCC pavements ranged from about 0.18 to 0.35. The temperatures of some PCC pavements are also measured and calculated. We then consider how the albedos of the constituent materials of the PCC (stone, sand and cement) contribute to the albedos of the resulting finished concrete. The albedos of a set of chip sealed pavements in San Jose, CA, were measured and correlated with the times of their placement. It is found that the albedos decrease with age (and use) but remain higher than that of standard asphalt concrete (AC) for about five years. After t hat, the albedos of the chip seals are about 0.12, similar to aged AC. The fact that many PCC pavements have albedos at least twice as high as aged AC suggests that it is possible to have pavement albedos that remain high for many years.

  2. Cooler reflective pavements give benefits beyond energy savings: durability and illumination

    Energy Technology Data Exchange (ETDEWEB)

    Pomerantz, Melvin; Akbari, Hashem; Harvey, John T.

    2000-06-01

    City streets are usually paved with asphalt concrete because this material gives good service and is relatively inexpensive to construct and maintain. We show that making asphalt pavements cooler, by increasing their reflection of sunlight, may lead to longer lifetime of the pavement, lower initial costs of the asphalt binder, and savings on street lighting and signs. Excessive glare due to the whiter surface is not likely to be a problem.

  3. Reflections on urban space: streets through time

    Directory of Open Access Journals (Sweden)

    Simon T. Loseby

    2011-05-01

    Full Text Available This paper offers a general reflection on late antique and early medieval urban space, situating the essays in the collection Le trasformazioni dello spazio urbano nell’alto medioevo (secoli V-VIII. Città mediterranee a confronto (RM Rivista 2010, 2 within a wider framework. It focuses in particular on the long late antique phase of Mediterrranean urban history, and the enduring ideological significance of urbanism in the early medieval west.

  4. Strategies for cooler cities? Ecophysiological responses of semi-arid street trees to storm water harvesting

    Science.gov (United States)

    DeMets, C. M.; Pavao-zuckerman, M.; Barron-Gafford, G.

    2013-12-01

    As the southwestern U.S. moves into an uncertain future in terms of water supply and climate, communities are seeking creative ways to harvest urban runoff. One such solution is to implement water-sensitive urban design features such as rain basins, which are designed to capture and facilitate infiltration of precipitation and storm water as it runs off impermeable surfaces like streets and sidewalks. Rain basins essentially act as temporary cisterns, allowing a given rain event to have a much larger impact in recharging soil water profiles. In this sense, even a 'small' rain may yield a more saturated soil profile and stimulate plant physiological activity well beyond plants that lack this additional moisture input. However, the impacts of rain basins on plant function remain unquantified. Therefore, the purpose of our research is to characterize the performance of native mesquite trees in basins relative to non-basin native mesquites. To answer our question, we randomly sampled basin and non-basin native mesquites in two different neighborhoods in Tucson, AZ, and characterized their response to precipitation events. We measured stomatal conductance, a proxy for transpiration, on the first and third days following rain events in 2013. Numerous environmental factors, such as photosynthetically available radiation (PAR), temperature, relative humidity, and soil moisture, were also measured in order to explore relationships with conductance. These measurements were conducted before and during monsoon season in order to determine the significance of water in basin performance, enabling us to better characterize plant response to medium (6 to 12 mm) rain events. Findings from this study indicate that basin and non-basin mesquites have similar pre-monsoon conductance rates, with a mean basin value of 70 +/-10 mmol/(m2*s) and a mean non-basin value of 57 +/-6 mmol/(m2*s) at peak conductance. In contrast, during the monsoon, basin mesquites showed significantly higher

  5. Potential benefits of solar reflective car shells: cooler cabins, fuel savings and emission reductions

    Energy Technology Data Exchange (ETDEWEB)

    Levinson, Ronnen; Pan, Heng; Ban-Weiss, George; Rosado, Pablo; Paolini, Riccardo; Akbari, Hashem

    2011-05-11

    Abstract: Vehicle thermal loads and air conditioning ancillary loads are strongly influenced by the absorption of solar energy. The adoption of solar reflective coatings for opaque surfaces of the vehicle shell can decrease the ?soak? temperature of the air in the cabin of a vehicle parked in the sun, potentially reducing the vehicle?s ancillary load and improving its fuel economy by permitting the use of a smaller air conditioner. An experimental comparison of otherwise identical black and silver compact sedans indicated that increasing the solar reflectance (?) of the car?s shell by about 0.5 lowered the soak temperature of breath-level air by about 5?6?C. Thermal analysis predicts that the air conditioning capacity required to cool the cabin air in the silver car to 25?C within 30min is 13percent less than that required in the black car. Assuming that potential reductions in AC capacity and engine ancillary load scale linearly with increase in shell solar reflectance, ADVISOR simulations of the SC03 driving cycle indicate that substituting a typical cool-colored shell (?=0.35) for a black shell (?=0.05) would reduce fuel consumption by 0.12L per 100km (1.1percent), increasing fuel economy by 0.10kmL?1 [0.24mpg] (1.1percent). It would also decrease carbon dioxide (CO2) emissions by 2.7gkm?1 (1.1percent), nitrogen oxide (NOx) emissions by 5.4mgkm?1 (0.44percent), carbon monoxide (CO) emissions by 17mgkm?1 (0.43percent), and hydrocarbon (HC) emissions by 4.1mgkm?1 (0.37percent). Selecting a typical white or silver shell (?=0.60) instead of a black shell would lower fuel consumption by 0.21L per 100km (1.9percent), raising fuel economy by 0.19kmL?1 [0.44mpg] (2.0percent). It would also decrease CO2 emissions by 4.9gkm?1 (1.9percent), NOx emissions by 9.9mgkm?1 (0.80percent), CO emissions by 31mgkm?1 (0.79percent), and HC emissions by 7.4mgkm?1 (0.67percent). Our simulations may underestimate emission reductions because emissions in standardized driving cycles are

  6. Evaporative cooler including one or more rotating cooler louvers

    Energy Technology Data Exchange (ETDEWEB)

    Gerlach, David W

    2015-02-03

    An evaporative cooler may include an evaporative cooler housing with a duct extending therethrough, a plurality of cooler louvers with respective porous evaporative cooler pads, and a working fluid source conduit. The cooler louvers are arranged within the duct and rotatably connected to the cooler housing along respective louver axes. The source conduit provides an evaporative cooler working fluid to the cooler pads during at least one mode of operation.

  7. The Recycler Electron Cooler

    Energy Technology Data Exchange (ETDEWEB)

    Shemyakin, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Prost, L. R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2013-03-19

    The Recycler Electron cooler was the first (and so far, the only) cooler working at a relativistic energy (γ = 9.5). It was successfully developed in 1995-2004 and was in operation at Fermilab in 2005-2011, providing cooling of antiprotons in the Recycler ring. This paper describes the cooler, difficulties in achieving the required electron beam parameters and the ways to overcome them, cooling measurements, and details of operation.

  8. Thinking and Meddling with Boundaries: Critical Reflections on Matthew Weinstein's Narrative of Street Medics, Red-Zones and Glop

    Science.gov (United States)

    Alsop, Steve

    2015-01-01

    In pursuit of more mindful notions of hybridity, this review essay provides a series of reflections on Mathew Weinstein's representations of Street Medics and "sciences for the red zones of neoliberalism". My analysis draws on three popular ways of thinking with boundaries to offer a critical reading of the boundary-work that the…

  9. Vacuum Camera Cooler

    Science.gov (United States)

    Laugen, Geoffrey A.

    2011-01-01

    Acquiring cheap, moving video was impossible in a vacuum environment, due to camera overheating. This overheating is brought on by the lack of cooling media in vacuum. A water-jacketed camera cooler enclosure machined and assembled from copper plate and tube has been developed. The camera cooler (see figure) is cup-shaped and cooled by circulating water or nitrogen gas through copper tubing. The camera, a store-bought "spy type," is not designed to work in a vacuum. With some modifications the unit can be thermally connected when mounted in the cup portion of the camera cooler. The thermal conductivity is provided by copper tape between parts of the camera and the cooled enclosure. During initial testing of the demonstration unit, the camera cooler kept the CPU (central processing unit) of this video camera at operating temperature. This development allowed video recording of an in-progress test, within a vacuum environment.

  10. Shipboard electronics thermoacoustic cooler

    OpenAIRE

    Ballister, Stephen C.; McKelvey, Dennis J.

    1995-01-01

    A thermoacoustic refrigerator that was optimized for preservation of biological samples in space, was modified for use as a cooler for the CV-2095 shipboard radar electronics rack. The thermoacoustic cooler was tested in the laboratory and demonstrated at sea aboard USS DEYO (DD-989). In the laboratory, using a calibrated heat load, the data acquisition system was able to account for the total energy balance to within 4%. At the highest operating power aboard ship, 226.6 Watts of acoustic pow...

  11. LEIR electron cooler status

    CERN Document Server

    Tranquille, G; Parkhomchuk, V; Prieto, V; Sautier, R

    2006-01-01

    The electron cooler for LEIR is the first of a new generation of coolers being commissioned for fast phase space cooling of ion beams in storage rings. It is a stateof- the-art cooler incorporating all the recent developments in electron cooling technology (adiabatic expansion, electrostatic bend, variable density electron beam) and is designed to deliver up to 600 mA of electron current for the cooling and stacking of Pb54+ ions in the frame of the ions for LHC project. In this paper we present our experience with the commissioning of the new device as well as the first results of ion beam cooling with a high-intensity variable-density electron beam.

  12. Materials for syngas coolers

    Science.gov (United States)

    Perkins, R. A.; Morse, G.; Coons, W. C.

    1982-08-01

    A technical basis for materials selection and laboratory testing of practical boiler tube materials which will provide reliable long term service in syngas coolers for coal gasification combined cycle power plants is outlined. The resistance of low alloy steel, stainless steels, and aluminum rich coatings to attach by a high sulfur, medium Btu coal gasification atmosphere was evaluated at 300 to 500 deg C. The materials may have adequate resistance for long time service in radiant coolers operating up to 500 deg C on high sulfur medium Btu gas. Performance is analyzed for thermodynamic and kinetic properties and recommendations for long term tests and development of protective coatings are presented.

  13. Cooler-Lower Down

    Science.gov (United States)

    Deeson, Eric

    1971-01-01

    Reports a verification that hot water begins to freeze sooner than cooler water. Includes the investigations that lead to the conclusions that convection is a major influence, water content may have some effect, and the melting of the ice under the container makes no difference on the experimental results. (DS)

  14. Metal content in street dust as a reflection of atmospheric dust emissions from coal power plants, metal smelters, and traffic.

    Science.gov (United States)

    Žibret, Gorazd; Van Tonder, Danel; Žibret, Lea

    2013-07-01

    Resuspended street dust is a source of inhalable particles in urban environments. Despite contaminated street dust being a possible health risk factor for local population, little is known about the contribution of atmospheric dust emissions and other factors to the content of toxic metals in street dust. The impact of smelting, traffic, and power plants on metal contaminates in street dust is the focus of street dust sampling at 46 locations in the Witbank area (Republic of South Africa). This area is characterized by numerous open-pit coal mines in the Karoo coal basin, which provides a cheap source of energy to numerous metallurgical smelters and ironworks and supplies coal to the coal-fired power plants located nearby. Street dust was collected on asphalt or concrete surfaces with hard plastic brushes, avoiding collecting of possible sand, soil, or plant particles. Chemical analysis was done on the traffic which contributes to the high concentrations of Cu, Pb, Sb, and Sn, with the highest impacts detected in the town of Witbank. The second source is associated with the metal smelting industry, contributing to Fe, Co, Mn, and V emissions. The highest factor scores were observed around four metallurgical smelter operations, located in the Ferrobank, Highveld, and Clewer industrial areas. Impact of vanadium smelter to street dust composition could still be detected some 20 km away from the sources. Exceptionally high concentrations of Cr were observed in four samples collected next to the Ferrobank industrial area, despite Cr not being loaded in factor 2. The last source of the pollution is most probably fly ash associated with the coal-fired power plants and fly ash dumps. Elements which are associated with this source are Al, Sr, and Li. This factor is abundant in the coal mining part of the study area.

  15. Superfluid Vortex Cooler

    Science.gov (United States)

    Tanaeva, I. A.; Lindemann, U.; Jiang, N.; de Waele, A. T. A. M.; Thummes, G.

    2004-06-01

    A superfluid vortex cooler (SVC) is a combination of a fountain pump and a vortex cooler. The working fluid in the SVC is 4He at a temperature below the lambda line. The cooler has no moving parts, is gravity independent, and hardly requires any additional infrastructure. At saturated vapour pressure the SVC is capable of reaching a temperature as low as 0.75 K. At pressures close to the melting pressure the temperature can be brought down to 0.65 K. As the SVC operates only below the lambda line, it has to be precooled e.g. by a liquid-helium bath or a cryocooler. As a first step of our research we have carried out a number of experiments, using a liquid-helium bath as a precooler for the SVC. In this arrangement we have reached temperatures below 1 K with 3.5 mW heating power supplied to the fountain part of the SVC at 1.4 K. The next step was combining the SVC with a pulse tube refrigerator (PTR), developed at the University of Giessen. It is a two-stage G-M type refrigerator with 3He as a working fluid that reached a lowest temperature of 1.27 K. In this contribution we report on the results of the SVC tests in liquid helium and the progress in the integration of the SVC with the PTR.

  16. Microsystem Cooler Development

    Science.gov (United States)

    Moran, Matthew E.; Wesolek, Danielle M.; Berhane, Bruk T.; Rebello, Keith J.

    2004-01-01

    A patented microsystem Stirling cooler is under development with potential application to electronics, sensors, optical and radio frequency (RF) systems, microarrays, and other microsystems. The microsystem Stirling cooler is most suited to volume-limited applications that require cooling below the ambient or sink temperature. Primary components of the planar device include: two diaphragm actuators that replace the pistons found in traditional-scale Stirling machines; and a micro-regenerator that stores and releases thermal energy to the working gas during the Stirling cycle. The use of diaphragms eliminates frictional losses and bypass leakage concerns associated with pistons, while permitting reversal of the hot and cold sides of the device during operation to allow precise temperature control. Three candidate microregenerators were custom fabricated for initial evaluation: two constructed of porous ceramic, and one made of multiple layers of nickel and photoresist in an offset grating pattern. An additional regenerator was prepared with a random stainless steel fiber matrix commonly used in existing Stirling machines for comparison to the custom fabricated regenerators. The candidate regenerators were tested in a piezoelectric-actuated test apparatus designed to simulate the Stirling refrigeration cycle. In parallel with the regenerator testing, electrostatically-driven comb-drive diaphragm actuators for the prototype device have been designed for deep reactive ion etching (DRIE) fabrication.

  17. Urban streets

    NARCIS (Netherlands)

    Schönfeld, von Kim Carlotta; Bertolini, Luca

    2017-01-01

    Today's urban streets are usually planned for purposes of mobility: pedestrians, as well as a variety of vehicles such as cars, trucks, and sometimes bicycles, are usually factored into an urban street plan. However, urban streets are also increasingly recognized as public spaces, accommodating stre

  18. Street children

    Directory of Open Access Journals (Sweden)

    Rončević Nevenka

    2013-01-01

    Full Text Available According to UNICEF, street child is any child under the age of 18 for whom the street has become home and/or source of income and which is not adequately protected or supervised by adult, responsible person. It has been estimated that there are between 100 and 150 million street children worldwide. Life and work on the street have long term and far-reaching consequences for development and health of these children. By living and working in the street, these children face the highest level of risk. Street children more often suffer from the acute illness, injuries, infection, especially gastrointestinal, acute respiratory infections and sexually transmitted diseases, inadequate nutrition, mental disorders, and drug abuse. They are more often victims of abuse, sexual exploitation, trafficking; they have higher rate of adolescent pregnancy than their peers from poor families. Street children and youth have higher rates of hospitalization and longer hospital stay due to seriousness of illness and delayed health care. Street children/youth are reluctant to seek health care, and when they try, they face many barriers. Street children are invisible to the state and their number in Serbia is unknown. Recently, some non­governmental organizations from Belgrade, Novi Sad and Nis have recognized this problem and tried to offer some help to street children, by opening drop­in centers, but this is not enough. To solve this problem, an engagement of the state and the whole community is necessary, and primary responsibility lies in health, social and educational sector. The best interests of the child must serve as a basic guideline in all activities aimed at improving health, quality of life and rights of children involved in the life and work in the street.

  19. Impulse sales cooler. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, Per Henrik (DTI, Taastrup (Denmark))

    2010-11-15

    In the past years, the use of impulse coolers has increased considerably and it is estimated that at least 30.000 are installed in shops in Denmark. In addition, there are many small barrel-shaped can coolers. Most impulse coolers are open, which results in a large consumption of energy, and the refrigeration systems are often quite inefficient. A typical impulse cooler uses app. 5 - 8 kWh/day corresponding to a consumption of energy in the magnitude of 60 GWh/year. For several years, the Danish company Vestfrost A/S has produced an impulse sales cooler in the high-efficiency end and the energy consumption of the cooler is measured to be 4.15 kWh/day. The POS72 cooler formed the baseline of this project. At the start-up meeting in 2008, several ideas were discussed with the objective to reduce energy consumption and to use natural refrigerants. Among the ideas were better air curtains, removable lids, better condensers, use of R600a refrigeration system and better insulation. Three generations of prototypes were built and tested in a climate chamber at Danish Technological Institute and the third generation showed very good performance: the energy consumption was measured to 2.215 kWh/day, which is a 47% reduction compared to the baseline. That was achieved by: 1) Improving the cold air cycling system including the air curtain. 2) Using the natural refrigerant R600a (isobutane) and the Danfoss NLE9KTK compressor, which has better efficiency compared to the compressor in the baseline product. 3) Using a box type condenser without fins (preventing dust build-up) and with a relatively high surface area. 4) Improving the insulation value of the plastic cabinet by reducing turbulence in the air gap between the plastic walls and improving the insulation value of the EPS moulded insulation surrounding the refrigeration system at the bottom of the cooler. 5) Preventing short-circuit of warm air around the condenser. 6) The improvements are cost efficient and will not add

  20. ENERGY STAR Certified Water Coolers

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 2.0 ENERGY STAR Program Requirements for Water Coolers that are effective as of February...

  1. City Streets

    Data.gov (United States)

    Minnesota Department of Natural Resources — This data set contains roadway centerlines for city streets found on the USGS 1:24,000 mapping series. In some areas, these roadways are current through the 2000...

  2. Development of the Sandia Cooler.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Terry Alan; Koplow, Jeffrey P.; Staats, Wayne Lawrence,; Curgus, Dita Brigitte; Leick, Michael Thomas.; Matthew, Ned Daniel; Zimmerman, Mark D.; Arienti, Marco; Gharagozloo, Patricia E.; Hecht, Ethan S.; Spencer, Nathan A.; Vanness, Justin William.; Gorman, Ryan

    2013-12-01

    This report describes an FY13 effort to develop the latest version of the Sandia Cooler, a breakthrough technology for air-cooled heat exchangers that was developed at Sandia National Laboratories. The project was focused on fabrication, assembly and demonstration of ten prototype systems for the cooling of high power density electronics, specifically high performance desktop computers (CPUs). In addition, computational simulation and experimentation was carried out to fully understand the performance characteristics of each of the key design aspects. This work culminated in a parameter and scaling study that now provides a design framework, including a number of design and analysis tools, for Sandia Cooler development for applications beyond CPU cooling.

  3. Street Politics

    Directory of Open Access Journals (Sweden)

    Michael J. Shapiro

    2012-03-01

    Full Text Available I write from Prague, where, unlike in most urban formations, the main city street plays an iconic role; it references a history of political protest. However, before elaborating on the protest iconography of the Prague street, Vaclavske nam, I want to locate the ways in which the design of urban space is actualized in everyday life in the cities of the world. Three functions stand out; the first involves dwelling, the second seeing, and the third moving. With respect to the first function – dwelling – the design partitions and coordinates residential, commercial and leisure functions. At times these are organized to segregate different classes (Robert Moses’ redesign of much of New York stands out with respect to the segregation function. With respect to the second function – seeing – the design of urban space is allegiance-inspiring; it involves sight lines that afford urban dwellers and visitors views of iconic buildings and statues, which reference key founding moments in the past and/or authoritative political functions in the present (Here, L’Enfants design for Washington DC stands out as exemplary. Its manifest intention was to make the buildings housing executive, legislative and judicial functions visible from many vantage points. Rarely are the streets themselves iconic. Their dominant role is involved with the effectuation of movement. As for this third function: As Lewis Mumford famously points out, streets were once part of an asterisk design, radiating out from an exemplary, often spiritual center...

  4. MEMS Stirling Cooler Development Update

    Science.gov (United States)

    Moran, Matthew E.; Wesolek, Danielle

    2003-01-01

    This presentation provides an update on the effort to build and test a prototype unit of the patented MEMS Stirling cooler concept. A micro-scale regenerator has been fabricated by Polar Thermal Technologies and is currently being integrated into a Stirling cycle simulator at Johns Hopkins University Applied Physics Laboratory. A discussion of the analysis, design, assembly, and test plans for the prototype will be presented.

  5. Street level society

    DEFF Research Database (Denmark)

    Vinum, Christine; Nissen, Morten

    2006-01-01

    , and partly from the decentralizing and specializing efforts characteristic of the Danish welfare state and its institutions. We discuss a general turn towards street level interventions to address the problems of social exclusion, as well as different attempts to create what we term street level heterotopias......This paper aims to reflect on research findings from different empirical studies of social work with young drug users and socially excluded young people in Copenhagen. In the paper we account for historical changes in social policy and interventions into young people's drug taking in Copenhagen......, and we discuss some of the most central dilemmas in today's social work with young drug users. Among other things, we identify pervasive marginalizing dynamics in the social system that result partly from the deep-rooted cultural dichotomy between stigma and taboo that organizes the drug issue...

  6. Simple street tree sampling

    Science.gov (United States)

    David J. Nowak; Jeffrey T. Walton; James Baldwin; Jerry. Bond

    2015-01-01

    Information on street trees is critical for management of this important resource. Sampling of street tree populations provides an efficient means to obtain street tree population information. Long-term repeat measures of street tree samples supply additional information on street tree changes and can be used to report damages from catastrophic events. Analyses of...

  7. "The Cow Loves To Learn": The Hao-Xue-Xin Learning Model as a Reflection of the Cultural Relevance of "Zhima Jie," China's "Sesame Street."

    Science.gov (United States)

    Li, Jin; Li, Jimei

    2002-01-01

    Examined the cultural basis and relevance of "Zhima Jie," a Chinese adaptation of "Sesame Street." Found that most of 3- to 6-year-olds in the sample desired books and learning materials, with disadvantaged children more likely than more advantaged children to desire books and learning materials. Older children showed a greater…

  8. Overview of Sumitomo coolers and Dewars for space use

    Science.gov (United States)

    Kanao, Kenichi; Narasaki, Katsuhiro; Tsunematsu, Shoji; Ootsuka, Kiyomi; Okabayashi, Akinobu; Mitsuda, Kazuhisa; Murakami, Hiroshi; Nakagawa, Takao; Nishibori, Toshiyuki; Kikuchi, Ken'ichi; Sato, Ryota; Sugita, Hiroyuki; Sato, Yoichi; Murakami, Masahide

    2016-05-01

    Sumitomo Heavy Industries, ltd. (SHI) has been developing cooler and Dewar technology for space application with Japan Aerospace Exploration Agency. SHI has four types of coolers to cover temperature range from 1.7K to 80K or more. Those are Single stage Stirling coolers for 80K, two-stage Stirling coolers for 20K, 4K-class cooler and 1K-class cooler. 4K and 1K class coolers consist of a Joule-Thomson cooler and a two-stage Stirling as a pre-cooler. SHI also provided Dewars. In this paper, SHI's cooler and Dewar technology are described.

  9. Study of a thermoacoustic Stirling cooler

    Energy Technology Data Exchange (ETDEWEB)

    Spoelstra, S.; Tijani, M.E.H. [ECN Energy Efficiency in the Industry, Petten (Netherlands)

    2007-05-15

    A thermoacoustic-Stirling cooler is built and performance measurements are carried out. The cooler uses the acoustic power produced by a linear motor to pump heat through a regenerator from a cold heat exchanger to an ambient one. The cooler incorporates a compact acoustic network to create the traveling-wave phasing necessary to operate in a Stirling cycle. The network has a coaxial topology instead of the toroidal one usually applied. The design, construction and performance measurements of the cooler are presented. A measured coefficient of performance relative to Carnot of 25% and a low temperature of -54C are achieved by the cooler. This efficiency surpasses the performance of the most efficient standing wave cooler by almost a factor of two.

  10. Street Talk

    Directory of Open Access Journals (Sweden)

    Avital Ronell

    1986-09-01

    Full Text Available This essay investigates the fragile intersection where rumor and a more "authentic" modality of language can be shown to cross over into one another. Treating the relationship of Benjamin, Heidegger and Rousseau to rumoro-logical paranoia, "Street-Talk" interprets the epistemological teetering between the knowing and not-knowing around which Fama articulates her power. All three of these thinkers are shown to be exemplarily afflicted by rumorous utterances and share a drive to create, in their works, a rumor control center. Often these controls take over the features which they attempt to disown; thus the greatest moment of truth-telling appropriates the form of inferential small-talk. The essay analyzes a temporality of writing disclosed by Rousseau's Promenades in terms of an après-ma-mort structure. Finally, guided by Blanchot's insights and Huet's notion of monsterized publicity, the essay addresses the rapport of rumor to oeuvre: Ecce Fama .

  11. Development trends in IR detector coolers

    Science.gov (United States)

    Mai, M.; Rühlich, I.; Wiedmann, Th.; Rosenhagen, C.

    2009-05-01

    For different IR application specific cooler requirements are needed to achieve best performance on system level. Handheld applications require coolers with highest efficiency and lowest weight. For application with continuous operation, i.e. border surveillance or homeland security, a very high MTTF is mandatory. Space applications additionally require extremely high reliability. In other application like fighter aircraft sufficient cooling capacity even at extreme high reject temperatures has to be provided. Meeting all this requirements within one cooler design is technically not feasible. Therefore, different coolers designs like integral rotary, split rotary or split linear are being employed. The use of flexure bearings supporting the driving mechanism has generated a new sub-group for the linear coolers; also, the coolers may either use a motor with moving magnet or with moving coil. AIM has mainly focussed on long life linear cooler technology and therefore developed a series of moving magnet flexure bearing compressors which meets MTTF's exceeding 20,000h (up to 50,000h with a Pulse-Tube coldfinger). These compressors have a full flexure bearing support on both sides of the driving mechanism. Cooler designs are being compared in regard to characteristic figures as described above.

  12. The stack induced draft aerial cooler (SIDAC)

    Energy Technology Data Exchange (ETDEWEB)

    Hircock, N.C. [NC Hircock Process Consulting Ltd., Calgary, AB (Canada)]|[Patching Associates Acoustical Engineering Ltd. Calgary, AB (Canada)

    2007-07-01

    The oil and gas industry uses stack induced draft aerial coolers (SIDAC) for process cooling in noise sensitive areas or in areas where no electrical power is available. The technology produces zero noise, zero operating costs and zero emissions. This paper examined the use, operation and economics of fanless, noiseless aerial coolers. Although retrofitting to convert from fin-fan to SIDAC is not viable, this paper illustrated one common application where the installation of a tapered stack over a cooler could work together with variable speed fan drives to enhance the noise suppression achieved by variable speed fan drives. A stack assisted draft air cooler (SADAC) was installed over a conventional engine cooler enclosing the engine exhaust and muffler. The exhaust stack was also acoustically lined to augment the noise suppression of the engine silencer itself. The waste heat of the engine exhaust, combined with the heat from the cooler discharge, was used to create a negative pressure behind the cooler fan. Therefore, at night the fan could back off in speed. Since fan noise is proportional to speed to the exponent 5, even a 20 per cent reduction of fan speed generates a noticeable noise reduction. The noise directive of the Alberta Energy and Utilities Board is for lower noise levels at night rather than daytime. Therefore, this innovation allows plant operators to run coolers at full capacity in the day while backing off fan speed at night. It was concluded that substantial benefits can be achieved by SIDAC and SADAC technology in the areas of noise control, process improvements and emission reductions. The capital costs of using these devices are comparable with conventional systems, and operating costs are reduced.

  13. Mitigation of Syngas Cooler Plugging and Fouling

    Energy Technology Data Exchange (ETDEWEB)

    Bockelie, Michael J. [Reaction Engineering International, Salt Lake City, UT (United States)

    2015-06-29

    This Final Report summarizes research performed to develop a technology to mitigate the plugging and fouling that occurs in the syngas cooler used in many Integrated Gasification Combined Cycle (IGCC) plants. The syngas cooler is a firetube heat exchanger located downstream of the gasifier. It offers high thermal efficiency, but its’ reliability has generally been lower than other process equipment in the gasification island. The buildup of ash deposits that form on the fireside surfaces in the syngas cooler (i.e., fouling) lead to reduced equipment life and increased maintenance costs. Our approach to address this problem is that fouling of the syngas cooler cannot be eliminated, but it can be better managed. The research program was funded by DOE using two budget periods: Budget Period 1 (BP1) and Budget Period 2 (BP2). The project used a combination of laboratory scale experiments, analysis of syngas cooler deposits, modeling and guidance from industry to develop a better understanding of fouling mechanisms and to develop and evaluate strategies to mitigate syngas cooler fouling and thereby improve syngas cooler performance. The work effort in BP 1 and BP 2 focused on developing a better understanding of the mechanisms that lead to syngas cooler plugging and fouling and investigating promising concepts to mitigate syngas cooler plugging and fouling. The work effort focused on the following: • analysis of syngas cooler deposits and fuels provided by an IGCC plant collaborating with this project; • performing Jet cleaning tests in the University of Utah Laminar Entrained Flow Reactor to determine the bond strength between an ash deposit to a metal plate, as well as implementing planned equipment modifications to the University of Utah Laminar Entrained Flow Reactor and the one ton per day, pressurized Pilot Scale Gasifier; • performing Computational Fluid Dynamic modeling of industrially relevant syngas cooler configurations to develop a better

  14. Allegheny County Street Centerlines

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains the locations of the street centerlines for vehicular and foot traffic in Allegheny County. Street Centerlines are classified as Primary...

  15. Allegheny County Street Centerlines

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains the locations of the street centerlines for vehicular and foot traffic in Allegheny County. Street Centerlines are classified as Primary Road,...

  16. Allegheny County Street Centerlines

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains the locations of the street centerlines for vehicular and foot traffic in Allegheny County. Street Centerlines are classified as Primary Road,...

  17. Small high cooling power space cooler

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, T. V.; Raab, J.; Durand, D.; Tward, E. [Northrop Grumman Aerospace Systems Redondo Beach, Ca, 90278 (United States)

    2014-01-29

    The small High Efficiency pulse tube Cooler (HEC) cooler, that has been produced and flown on a number of space infrared instruments, was originally designed to provide cooling of 10 W @ 95 K. It achieved its goal with >50% margin when limited by the 180 W output ac power of its flight electronics. It has also been produced in 2 stage configurations, typically for simultaneously cooling of focal planes to temperatures as low as 35 K and optics at higher temperatures. The need for even higher cooling power in such a low mass cryocooler is motivated by the advent of large focal plane arrays. With the current availability at NGAS of much larger power cryocooler flight electronics, reliable long term operation in space with much larger cooling powers is now possible with the flight proven 4 kg HEC mechanical cooler. Even though the single stage cooler design can be re-qualified for those larger input powers without design change, we redesigned both the linear and coaxial version passive pulse tube cold heads to re-optimize them for high power cooling at temperatures above 130 K while rejecting heat to 300 K. Small changes to the regenerator packing, the re-optimization of the tuned inertance and no change to the compressor resulted in the increased performance at 150 K. The cooler operating at 290 W input power achieves 35 W@ 150 K corresponding to a specific cooling power at 150 K of 8.25 W/W and a very high specific power of 72.5 W/Kg. At these powers the cooler still maintains large stroke, thermal and current margins. In this paper we will present the measured data and the changes to this flight proven cooler that were made to achieve this increased performance.

  18. Street typology in Kathmandu and street transformation

    Directory of Open Access Journals (Sweden)

    Bijaya K. Shrestha

    2011-01-01

    Full Text Available The lively and pedestrian friendly streets of the Malla period and the unique streetscape of the Rana period, including streets in planned and haphazardly developed areas, are being rapidly transformed due to unmanaged urban growth, chaotic construction and a growing number of vehicles in Kathmandu. This has destroyed the physical form, reduced social activities, increased accidents and decreased pedestrian comfort on all types of streets. These negative consequences cannot be addressed through the existing legal and institutional frameworks of the urban development and traffic management authorities. Even recent street improvements have discouraged pedestrian movement, degraded the streetscape and replaced public spaces with traffic. This has further congested pedestrians and traffic in areas that were already crowded. To reverse this trend and to enhance the qualities of traditional streets of Kathmandu, a threefold urban design strategy is essential. This will decentralise business activities from urban centres, improve transitional spaces between streets (and sidewalks and ground floor activities of buildings on both sides of the streets, and strictly enforce traffic management, all supported by flexible design guidelines, incentives and consensus among various stakeholders.

  19. Micro cryogenic coolers for IR imaging

    Science.gov (United States)

    Lewis, Ryan; Wang, Yunda; Cooper, Jill; Lin, Martin M.; Bright, Victor M.; Lee, Y. C.; Bradley, Peter E.; Radebaugh, Ray; Huber, Marcia L.

    2011-06-01

    Joule-Thomson micro cryogenic coolers (MCCs) are a preferred approach for small and low power cryocoolers. With the same heat lift, MCC's power input can be only 1/10 of a thermoelectric cooler's input, and MCC's size can be only 1/10 of a Stirling cooler's size. With futuristic planar MCC and with high frequency MEMS compressors to be developed, its size can be reduced another order of magnitude. Such "invisible" cryocoolers may revolutionize future IR imaging systems. We will review our studies on the feasibility of MCC with an emphasis on: 1) high thermal isolation levels reaching 89,000 K/W; 2) custom-designed gas mixtures with refrigeration capabilities increased by 10X and pressure ratio reduced to only 4:1; 3) compressors with low pressure ratios; and 4) excellent scalability for further size reduction.

  20. Microsystem Cooler Concept Developed and Being Fabricated

    Science.gov (United States)

    Moran, Matthew E.

    2005-01-01

    A patented microsystem cooler concept has been developed by the NASA Glenn Research Center. It incorporates diaphragm actuators to produce the Stirling refrigeration cycle within a planar configuration compatible with the thermal management of electronics, sensors, optical and radiofrequency systems, microarrays, and other microsystems. The microsystem cooler is most suited to volume-limited applications that require cooling below the ambient or sink temperature. Johns Hopkins University Applied Physics Laboratory is conducting development testing and fabrication of a prototype under a grant from Glenn.

  1. TNO : your partner in air cooler development

    NARCIS (Netherlands)

    Fransen, J.G.B.

    2002-01-01

    At TNO we know that manufacturing air coolers is a highty competitive business. With TNO’s trusted expertise solidly behind you, your company can focus on reaching your target market with supporting product development through TNO’s research, consultancy and independent test data in conformity with

  2. INTERCONTINENTAL FINANCIAL STREET BEIJING

    Institute of Scientific and Technical Information of China (English)

    ZHANGCHUNYUE; FENGJIAYUN

    2005-01-01

    InterContinental Financial Street Beijing opened its doors on May 1st, 2005, just days before the world's business leaders flooded into town for the Fortune Global Forum.The first international luxury hotel in the Chinese capital's new and rapidly growing Financial Street business center, the InterContinental Financial Street Beijing is the flagship property of FnterContinental Hotels and Resorts on the Chinese mainland, and as such a pioneer in Beijing's future,

  3. Integrated thermal simulation of buildings and regenerative evaporative coolers

    Energy Technology Data Exchange (ETDEWEB)

    Rousseau, P.G.; Mathews, E.H.; Grobler, L.J. (Pretoria Univ. (South Africa). Centre for Experimental and Numerical Thermoflow)

    1994-01-01

    The thermal environment inside a building, fitted with a regenerative evaporative cooler, is influenced by the performance of the cooler. However, this performance is again influenced by the indoor air conditions. It means that the thermal performance of the building and the performance of the cooler cannot be separated. This paper proposes an innovative model for simulating the integrated thermal performance of buildings and regenerative evaporative coolers. The cooler model employs a standard single equation to characterize the performance of a cooler. Only the coefficients of this equation differs for different coolers. These coefficients are found from empirical performance data available from suppliers. The model was integrated with a comprehensive building thermal analysis program and verified successfully. This model now enables the designer to simulate any regenerative evaporative cooler connected to any building in any climatic region. The control strategy best suited for different off-design conditions can now also be investigated. (Author)

  4. 46 CFR 56.50-96 - Keel cooler installations.

    Science.gov (United States)

    2010-10-01

    ... ship's hull such that the cooler tubes are welded directly to the hull of the vessel with the hull forming part of the tube and satisfies all of the following: (i) The cooler structure is fabricated...

  5. Urban Street Gang Enforcement.

    Science.gov (United States)

    Institute for Law and Justice, Inc., Alexandria, VA.

    Strategies to enhance prosecution of gang-related crimes are presented, with a focus on enforcement and prosecution targeting urban street gangs. The model programs introduced offer strategies largely based on the practical experiences of agencies that participated in a demonstration program, the Urban Street Gang Drug Trafficking Enforcement…

  6. Widening Sesame Street.

    Science.gov (United States)

    Beck, T. Kay

    1979-01-01

    Traces the developmental history of Sesame Street from the initial efforts to obtain funding and set goals to present day importation of programs to other countries. It is recommended that Sesame Street producers incorporate Piagetian theories on cognitive development in order to realize learning gains. (Author)

  7. Ion beam coolers in nuclear physics

    CERN Document Server

    Äystö, J

    2003-01-01

    Cooling techniques for low-energy radioactive ion beams are reviewed together with applications on high-precision measurements of ground state properties of exotic nuclei. The emphasis in the presentation is on cooling, bunching and improving the overall characteristics of ion beams by RFQ-driven buffer gas cooling devices. Application of cooled and bunched beams in collinear laser spectroscopy to extract isotope shifts and hyperfine structure are presented with examples on radioactive Ti, Zr and Hf isotopes. The impact of the new-generation coolers on mass measurements of short-lived nuclei is discussed with examples on precision measurements of masses of super-allowed beta emitters. As a new concept, decay spectroscopy of radioactive ions trapped in a cooler Penning trap is presented.

  8. Measurements of Flat-Plate Milk Coolers

    Directory of Open Access Journals (Sweden)

    Vlastimil Nejtek

    2014-01-01

    Full Text Available Measuring in laboratory conditions was performed with the aim to collect a sufficient quantity of measured data for the qualified application of flat-plate coolers in measuring under real operating conditions. The cooling water tank was filled with tap water; the second tank was filled with water at a temperature equivalent to freshly milked milk. At the same time, pumps were activated that delivered the liquids into the flat-plate cooler where heat energy was exchanged between the two media. Two containers for receiving the run-out liquid were placed on the outputs from the cooler; here, temperature was measured with electronic thermometer and volume was measured with calibrated graduated cylinder. Flow rate was regulated both on the side of the cooling fluid and on the side of the cooled liquid by means of a throttle valve. The measurements of regulated flow-rates were repeated several times and the final values were calculated using arithmetic average. To calculate the temperature coefficient and the amount of brought-in and let-out heat, the volume measured in litres was converted to weight unit. The measured values show that the volume of exchanged heat per weight unit increases with the decreasing flow-rate. With the increasing flow-rate on the throttled side, the flow-rate increases on the side without the throttle valve. This phenomenon is caused by pressure increase during throttling and by the consequent increase of the diameter of channels in the cooler at the expense of the opposite channels of the non-throttled part of the circuit. If the pressure is reduced, there is a pressure decrease on the external walls of opposite channels and the flow-rate increases again. This feature could be utilised in practice: a pressure regulator on one side could regulate the flow-rate on the other side. The operating measurement was carried out on the basis of the results of laboratory measurements. The objective was to determine to what extent the

  9. Radiant coolers - Theory, flight histories, design comparisons and future applications

    Science.gov (United States)

    Donohoe, M. J.; Sherman, A.; Hickman, D. E.

    1975-01-01

    Radiant coolers have been developed for application to the cooling of infrared detectors aboard NASA earth observation systems and as part of the Defense Meteorological Satellite Program. The prime design constraints for these coolers are the location of the cooler aboard the satellite and the satellite orbit. Flight data from several coolers indicates that, in general, design temperatures are achieved. However, potential problems relative to the contamination of cold surfaces are also revealed by the data. A comparison among the various cooler designs and flight performances indicates design improvements that can minimize the contamination problem in the future.

  10. Securing The Streets

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Chongqing takes back its streets from gangs six people were sentenced to death and another five received jail terms during trials in southwest China’s Chongqing Municipality on October 21 for their involvement in gang activity.

  11. Poole High Street study

    OpenAIRE

    Kilburn, David

    2007-01-01

    A presentation given to key decision makers within Poole to improve the retail offer in Poole High Street and leverage the benefit of improved town planning and the introduction of quality retail companies.

  12. Results from the Cooler and Lead Tests

    Energy Technology Data Exchange (ETDEWEB)

    Green, Michael A

    2010-06-10

    The report presents the results of testing MICE spectrometer magnet current leads on a test apparatus that combines both the copper leads and the high temperature superconducting (HTS) leads with a single Cryomech PT415 cooler and liquid helium tank. The current is carried through the copper leads from 300 K to the top of the HTS leads. The current is then carried through the HTS leads to a feed-through from the vacuum space to the inside of a liquid helium tank. The experiment allows one to measure the performance of both cooler stages along with the performance of the leads. While the leads were powered we measured the voltage drops through the copper leads, through the HTS leads, through spliced to the feed-through, through the feed-through and through the low-temperature superconducting loop that connects one lead to the other. Measurements were made using the leads that were used in spectrometer magnet 1A and spectrometer magnet 2A. These are the same leads that were used for Superbend and Venus magnets at LBNL. The IL/A for these leads was 5.2 x 10{sup 6} m{sup -1}. The leads turned out to be too long. The same measurements were made using the leads that were installed in magnet 2B. The magnet 2B leads had an IL/A of 3.3 x 10{sup 6} A m{sup -1}. This report discusses the cooler performance and the measured electrical performance of the lead circuit that contains the copper leads and the superconducting leads. All of the HTS leads that were installed in magnet 2B were current tested using this apparatus.

  13. Renaming Zagreb Streets and Squares

    Directory of Open Access Journals (Sweden)

    Jelena Stanić

    2009-06-01

    Full Text Available The paper deals with changes in street names in the city of Zagreb. Taking the Lower Town (Donji grad city area as an example, the first part of the paper analyses diachronic street name changes commencing from the systematic naming of streets in 1878. Analysis of official changes in street names throughout Zagreb’s history resulted in categorisation of five periods of ideologically motivated naming/name-changing: 1. the Croatia modernisation period, when the first official naming was put into effect, with a marked tendency towards politicisation and nationalisation of the urban landscape; 2. the period of the Kingdom of the Serbs, Croatians and Slovenians/Yugoslavia, when symbols of the new monarchy, the idea of the fellowship of the Southern Slavs, Slavenophilism and the pro-Slavic geopolitical orientation were incorporated into the street names, and when the national idea was highly evident and remained so in that process; 3. the period of the NDH, the Independent State of Croatia, with decanonisation of the tokens of the Yugoslavian monarchy and the Southern Slavic orientation, and reference to the Ustashi and the German Nazi and Italian Fascist movement; 4. the period of Socialism, embedding the ideals and heroes of the workers’ movement and the War of National Liberation into the canonical system; and, 5. the period following the democratic changes in 1990, when almost all the signs of Socialism and the Communist/Antifascist struggle were erased, with the prominent presence of a process of installing new references to early national culture and historical tradition. The closing part of the paper deals with public discussions connected with the selection of a location for a square to bear the name of the first president of independent Croatia, Franjo Tuđman. Analysis of these public polemics shows two opposing discourses: the right-wing political option, which supports a central position for the square and considers the chosen area to

  14. An introduction to closed cycle cryogenic coolers

    Science.gov (United States)

    Chellis, F. F.

    1980-01-01

    Closed cycle cryogenic coolers are used extensively for cooling infrared detectors and other specialized electronic devices. Because of the special requirements of each electro-optical system it is generally necessary to custom design the cryocooler to fit the requirements. Early and close cooperation between the electro-optical systems designer and the cryocooler manufacturer is important to the successful marriage of the cryocooler with the total electro-optical system. Limitations of various cryocooling techniques are presented, and consideration for cryocooling integration are addressed.

  15. The LEBIT ion cooler and buncher

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, S. [National Superconducting Cyclotron Laboratory, MSU, East Lansing, MI (United States); Bollen, G. [Facility for Rare Isotope Beams, MSU, East Lansing, MI (United States); Department of Physics and Astronomy, MSU, East Lansing, MI (United States); Ringle, R. [National Superconducting Cyclotron Laboratory, MSU, East Lansing, MI (United States); Savory, J. [National Institute of Standards and Technology, Boulder, CO (United States); Schury, P. [University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan)

    2016-04-21

    This paper presents a detailed description of the ion cooler and buncher, installed at the Low Energy Beam and Ion Trap Facility (LEBIT) at the National Superconducting Cyclotron Laboratory (NSCL). NSCL uses gas stopping to provide rare isotopes from projectile fragmentation for its low-energy physics program and to the re-accelerator ReA. The LEBIT ion buncher converts the continuous rare-isotope beam, delivered from the gas stopping cell, into short, low-emittance ion pulses, required for high-precision mass measurements with a 9.4 T Penning trap mass spectrometer. Operation at cryogenic temperatures, a simplified electrode structure and dedicated rugged electronics contribute to the high performance and reliability of the device, which have been essential to the successful LEBIT physics program since 2005. - Highlights: • High-performance ion cooler/buncher for rare-isotope Penning trap mass spectrometry. • Cryogenic operation lowers emittance; observed effect scales with temperature. • Optimized ion extraction schemes allow for time-of-flight based mass selection. • Observation and characterization of RF-phase dependent ion-pulse profiles.

  16. Interim cryo-cooler/detector report

    Energy Technology Data Exchange (ETDEWEB)

    Neufeld, K.; Ruhter, W. [Lawrence Livermore National Lab., CA (United States); Anderson, E. [CSA Engineering, Inc., Palo Alto, CA (United States)

    1995-04-19

    This report describes development of an electronic system designed to reduce vibration generated by a cryocooler. The diminished vibration makes it practical to use the active cooler to extract heat from a portable gamma ray detector instrument. The system was developed for a Sunpower cryocooler with an integrated counterbalance mass. The overall momentum cancellation approach is also applicable to other similar cryocoolers. The cancellation system is an assembly of several components tailored to accomplish the required vibration reduction with minimum power consumption and volume. It is designed to be powered by a 18--32 Volt battery. Up to ten harmonics of the 58.65 Hz drive frequency are controlled. In addition to the vibration cancellation, the electronic system produces the drive signal for the cryocooler and regulates the cooler temperature. The system employs a sinusoidal drive to reduce the amount of higher harmonic vibration. A digital signal processor (DSP) is used to perform the high speed vibration control. The Texas Instruments TMS320C31 processor is housed on a third-party board. A second board has analog-to-digital (A/D) and digital-to-analog (D/A) converters. The DSP was programmed in C. The physical system consists of two sets of electronics. The first is housed in a case that is separate from the detector unit.

  17. Study of a coaxial thermoacoustic-Stirling cooler

    Science.gov (United States)

    Tijani, M. E. H.; Spoelstra, S.

    2008-01-01

    A coaxial thermoacoustic-Stirling cooler is built and performance measurements are performed. The cooler uses the acoustic power produced by a linear motor to pump heat through a regenerator from a cold heat exchanger to an ambient one. The cooler incorporates a compact acoustic network to create the traveling-wave phasing necessary for the operation in a Stirling cycle. The network has a coaxial geometry instead of the toroidal one usually used in such systems. The design, construction and performance measurements of the cooler are presented. A measured coefficient of performance relative to Carnot of 25% and a low temperature of -54 °C are achieved by the cooler. This efficiency surpasses the performance of the most efficient standing-wave cooler by almost a factor of two.

  18. Study of a coaxial thermoacoustic-Stirling cooler

    Energy Technology Data Exchange (ETDEWEB)

    Spoelstra, S.; Tijani, M.E.H. [ECN Energy Efficiency in the Industry, Petten (Netherlands)

    2008-05-15

    A coaxial thermoacoustic-Stirling cooler is built and performance measurements are performed. The cooler uses the acoustic power produced by a linear motor to pump heat through a regenerator from a cold heat exchanger to an ambient one. The cooler incorporates a compact acoustic network to create the traveling-wave phasing necessary for the operation in a Stirling cycle. The network has a coaxial geometry instead of the toroidal one usually used in such systems. The design, construction and performance measurements of the cooler are presented. A measured coefficient of performance relative to Carnot of 25% and a low temperature of -54 degrees C are achieved by the cooler. This efficiency surpasses the performance of the most efficient standing-wave cooler by almost a factor of two.

  19. A Street With History

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A mixture of old and new,entertainment and business,Beijing’s Xidan Street is a booming area that attracts scores of visitors About 2 km west of Tiananmen Square is Xidan Street,one of the most famous com- mercial areas in Beijing and once the home of temples and entertainment venues. Xidan was a burgeoning commercial area as early as the Ming Dynasty (1368-1644). At that time,businessmen,travelers and traders from southwest China used to stop in Xidan before heading for other parts of Beijing.They fuelled a boom in shops,markets,

  20. Benjamin Franklin Street Academy.

    Science.gov (United States)

    Wohl, Seth F.

    In this evaluation report of the sixth year of operation of the Benjamin Franklin-Urban League Street Academy in New York City, it is recommended that the program be continued for the seventh year despite the poorer than expected student gains in all studied components and the sporadic student attendance pattern and high dropout rate. Students…

  1. Saving Mango Street

    Science.gov (United States)

    Van Winkle, Katie

    2012-01-01

    The author first learned about cultural diversity and racial justice in Mr. Sanderson's middle school English class. They read a book called "The House on Mango Street" by Sandra Cisneros and learned about a different culture, but also about a community with striking similarities to their own. The main character in the novel, Esperanza,…

  2. Assessment of Drinking Water Quality from Bottled Water Coolers.

    Directory of Open Access Journals (Sweden)

    Marzieh Farhadkhani

    2014-05-01

    Full Text Available Drinking water quality can be deteriorated by microbial and toxic chemicals during transport, storage and handling before using by the consumer. This study was conducted to evaluate the microbial and physicochemical quality of drinking water from bottled water coolers.A total of 64 water samples, over a 5-month period in 2012-2013, were collected from free standing bottled water coolers and water taps in Isfahan. Water samples were analyzed for heterotrophic plate count (HPC, temperature, pH, residual chlorine, turbidity, electrical conductivity (EC and total organic carbon (TOC. Identification of predominant bacteria was also performed by sequence analysis of 16S rDNA.The mean HPC of water coolers was determined at 38864 CFU/ml which exceeded the acceptable level for drinking water in 62% of analyzed samples. The HPC from the water coolers was also found to be significantly (P < 0.05 higher than that of the tap waters. The statistical analysis showed no significant difference between the values of pH, EC, turbidity and TOC in water coolers and tap waters. According to sequence analysis eleven species of bacteria were identified.A high HPC is indicative of microbial water quality deterioration in water coolers. The presence of some opportunistic pathogens in water coolers, furthermore, is a concern from a public health point of view. The results highlight the importance of a periodic disinfection procedure and monitoring system for water coolers in order to keep the level of microbial contamination under control.

  3. Ion beam cooler-buncher at the IGISOL facility

    Energy Technology Data Exchange (ETDEWEB)

    Nieminen, A.; Hakala, J.; Huikari, J.; Kolhinen, V.S.; Rinta-Antila, S.; Szerypo, J. [Dept. of Physics, Univ. of Jyvaeskylae (Finland); Billowes, J.; Campbell, P.; Moore, I.D.; Moore, R. [Schuster Lab., Univ. of Manchester (United Kingdom); Forest, D.H.; Thayer, H.L.; Tungate, G. [School of Physics and Astronomy, Univ. of Birmingham, Edgbaston (United Kingdom); Jokinen, A.; Aeystoe, J. [Dept. of Physics, Univ. of Jyvaeskylae (Finland)]|[CERN, Geneva (Switzerland)

    2003-07-01

    An ion beam cooler-buncher for manipulating low-energy radioactive ion beams at the IGISOL facility is described. The cooler-buncher serves as a source of cooled ion bunches for collinear laser spectroscopy and it will be used for preparation of ion bunches for injection into a Penning trap system. (orig.)

  4. Wall Street som kreationistisk forkynder

    DEFF Research Database (Denmark)

    Ekman, Susanne

    2016-01-01

    Artiklen gennemgår Karen Hos etnografi om Wall Street: "Liquidated: An ethnography of Wall Street" set i lyset af den offentlige debat vedrørende Goldman Sachs opkøb af Dong......Artiklen gennemgår Karen Hos etnografi om Wall Street: "Liquidated: An ethnography of Wall Street" set i lyset af den offentlige debat vedrørende Goldman Sachs opkøb af Dong...

  5. Bars in the Barkor Street

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In daytime,the Barkor Street is bustling with tourists,pious pilgrims and merchants crowded together.Only when darkness falls does the street become tranquil.Nevertheless,the area surrounding the Barkor Street(from Tibetan Hospital compound extending to east Beijing Road)is then revived by various kinds of bars.

  6. Multiply-interacting Vortex Streets

    CERN Document Server

    Oskouei, Babak G; Newton, Paul K

    2010-01-01

    We investigate the behavior of an infinite array of (reverse) von K'arm'an streets. Our primary motivation is to model the wake dynamics in large fish schools. We ignore the fish and focus on the dynamic interaction of multiple wakes where each wake is modeled as a reverse von K'arm'an street. There exist configurations where the infinite array of vortex streets is in relative equilibrium, that is, the streets move together with the same translational velocity. We examine the topology of the streamline patterns in a frame moving with the same translational velocity as the streets which lends insight into fluid transport through the mid-wake region. Fluid is advected along different paths depending on the distance separating two adjacent streets. Generally, when the distance between the streets is large enough, each street behaves as a single von K'arm'an street and fluid moves globally between two adjacent streets. When the streets get closer to each other, the number of streets that enter into partnership in...

  7. 76 FR 33631 - Energy Conservation Program: Test Procedures for Walk-In Coolers and Walk-In Freezers

    Science.gov (United States)

    2011-06-09

    ... regulatory text should read as set forth below: PART 431--ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL... measure the energy consumption of the components that make up the envelope of a walk-in cooler or walk-in... ``external conditions'' of the shared surface(s) must reflect the internal conditions of the adjacent walk-in...

  8. Street level society

    DEFF Research Database (Denmark)

    Vinum, Christine; Nissen, Morten

    2006-01-01

    , and we discuss some of the most central dilemmas in today's social work with young drug users. Among other things, we identify pervasive marginalizing dynamics in the social system that result partly from the deep-rooted cultural dichotomy between stigma and taboo that organizes the drug issue......, and partly from the decentralizing and specializing efforts characteristic of the Danish welfare state and its institutions. We discuss a general turn towards street level interventions to address the problems of social exclusion, as well as different attempts to create what we term street level heterotopias...... - sites of alternate ordering - where issues of drug use and other social problems can be dealt with and objectified in more flexible ways and handled as part of ongoing social practices of everyday life....

  9. Occupy Wall Street

    DEFF Research Database (Denmark)

    Jensen, Michael J.; Bang, Henrik

    2013-01-01

    This article analyzes the political form of Occupy Wall Street on Twitter. Drawing on evidence contained within the profiles of over 50,000 Twitter users, political identities of participants are characterized using natural language processing. The results find evidence of a traditional oppositio......This article analyzes the political form of Occupy Wall Street on Twitter. Drawing on evidence contained within the profiles of over 50,000 Twitter users, political identities of participants are characterized using natural language processing. The results find evidence of a traditional...... oppositional social movement alongside a legitimizing countermovement, but also a new notion of political community as an ensemble of discursive practices that are endogenous to the constitution of political regimes from the “inside out.” These new political identities are bound by thin ties of political...

  10. Modeling LED street lighting.

    Science.gov (United States)

    Moreno, Ivan; Avendaño-Alejo, Maximino; Saucedo-A, Tonatiuh; Bugarin, Alejandra

    2014-07-10

    LED luminaires may deliver precise illumination patterns to control light pollution, comfort, visibility, and light utilization efficiency. Here, we provide simple equations to determine how the light distributes in the streets. In particular, we model the illuminance spatial distribution as a function of Cartesian coordinates on a floor, road, or street. The equations show explicit dependence on the luminary position (pole height and arm length), luminary angle (fixture tilt), and the angular intensity profile (radiation pattern) of the LED luminary. To achieve this, we propose two mathematical representations to model the sophisticated intensity profiles of LED luminaries. Furthermore, we model the light utilization efficiency, illumination uniformity, and veiling luminance of glare due to one or several LED streetlamps.

  11. Thermo-Electron Ballistic Coolers or Heaters

    Science.gov (United States)

    Choi, Sang H.

    2003-01-01

    Electronic heat-transfer devices of a proposed type would exploit some of the quantum-wire-like, pseudo-superconducting properties of single-wall carbon nanotubes or, optionally, room-temperature-superconducting polymers (RTSPs). The devices are denoted thermo-electron ballistic (TEB) coolers or heaters because one of the properties that they exploit is the totally or nearly ballistic (dissipation or scattering free) transport of electrons. This property is observed in RTSPs and carbon nanotubes that are free of material and geometric defects, except under conditions in which oscillatory electron motions become coupled with vibrations of the nanotubes. Another relevant property is the high number density of electrons passing through carbon nanotubes -- sufficient to sustain electron current densities as large as 100 MA/square cm. The combination of ballistic motion and large current density should make it possible for TEB devices to operate at low applied potentials while pumping heat at rates several orders of magnitude greater than those of thermoelectric devices. It may also enable them to operate with efficiency close to the Carnot limit. In addition, the proposed TEB devices are expected to operate over a wider temperature range

  12. Beam accumulation with the SIS electron cooler

    CERN Document Server

    Steck, Markus; Blasche, K; Franczak, B J; Franzke, B; Winkler, T; Parkhomchuk, V V

    2000-01-01

    An electron cooling system has started operation in the heavy ion synchrotron SIS which is used to increase the intensity for highly charged ions. Fast transverse cooling of the hot ion beam after horizontal multiturn injection allows beam accumulation at the injection energy. After optimization of the accumulation process an intensity increase in a synchrotron pulse by more than one order of magnitude has been achieved. For highly charged ions the maximum number of particles has been increased from 1x10 sup 8 to 1x10 sup 9. For lighter ions intensity limitations have been encountered which are caused by the high phase space density of the cooled ion beam. Momentum spreads in the 10 sup - sup 4 range and emittances well below 10 pi mm mrad have been demonstrated. Recombination losses both in the residual gas and with the free cooler electrons determine the maximum intensity for highly charged ions. Systematic measurements of the recombination rates have been performed providing data for an optimum choice of t...

  13. Thermoelectric cooler application in electronic cooling

    Energy Technology Data Exchange (ETDEWEB)

    Reiyu Chein; Guanming Huang [National Chung Hsing University, Taichung City (China). Dept. of Mechanical Engineering

    2004-10-01

    This study addresses thermoelectric cooler (TEC) applications in the electronic cooling. The cold side temperature (T{sub c}) and temperature difference between TEC cold and hot sides ({delta}T=T{sub h} T{sub c}, T{sub h} temperature of hot side of TEC) were used as the parameters. The cooling capacity, junction temperature, coefficient of performance (COP) of TEC and the required heat sink thermal resistance at the TEC hot side were computed. The results indicated that the cooling capacity could be increased as T{sub c} increased and {delta}T was reduced. The maximum cooling capacity and chip junction temperature obtained were 207 W and 88{sup o}C, respectively. The required heat sink thermal resistance on TEC hot side was 0.054{sup o}C/W. Larger cooling capacity and higher COP could be obtained when the TEC was operated in the enforced regimes ({delta}T<0). However, TEC performance was restricted by the T{sub c} values and heat sink thermal resistance at the TEC hot side. A microchannel heat sink using water or air as the coolant was demonstrated to meet the low thermal heat sink resistance requirement for TEC operated at maximum cooling capacity conditions. (author)

  14. Thermoelectric cooler application in electronic cooling

    Energy Technology Data Exchange (ETDEWEB)

    Chein Reiyu; Huang Guanming

    2004-10-01

    This study addresses thermoelectric cooler (TEC) applications in the electronic cooling. The cold side temperature (T{sub c}) and temperature difference between TEC cold and hot sides ({delta}T=T{sub h}-T{sub c}, T{sub h}=temperature of hot side of TEC) were used as the parameters. The cooling capacity, junction temperature, coefficient of performance (COP) of TEC and the required heat sink thermal resistance at the TEC hot side were computed. The results indicated that the cooling capacity could be increased as T{sub c} increased and {delta}T was reduced. The maximum cooling capacity and chip junction temperature obtained were 207 W and 88 deg. C, respectively. The required heat sink thermal resistance on TEC hot side was 0.054 deg. C/W. Larger cooling capacity and higher COP could be obtained when the TEC was operated in the enforced regimes ({delta}T<0). However, TEC performance was restricted by the T{sub c} values and heat sink thermal resistance at the TEC hot side. A microchannel heat sink using water or air as the coolant was demonstrated to meet the low thermal heat sink resistance requirement for TEC operated at maximum cooling capacity conditions.

  15. Back Street Bounty

    Institute of Scientific and Technical Information of China (English)

    DAVID SPARKES

    2010-01-01

    @@ As soon as I stepped into the main street of the old city in Pingyao.Shanxi Province.I had a feeling I would not like the place.In fact.I basically made my mind up on the spot that I disliked it.It looked overly touristy.clichéd and lacking in the authenticity I was hoping for.My escape from Beijing's expat scene was looking shaky.

  16. Development of a hybrid cooler; Udvikling af hybridkoeler

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, P.; Toftegaard, R.; Weinkauff Kristoffersen, J. [Teknologisk Institut, Aarhus (Denmark); Juel Skovrup, M. [IPU, Kgs. Lyngby (Denmark); Ibsen, C. [VP Industries, Lem (Denmark)

    2013-04-15

    The project aims to develop a hybrid cooler which acts as a dry cooler in the winter and as cooling tower in summer. Energy consumption for cooling systems with a dry cooler and a cooling tower, respectively, is comparable in the winter months. This phase 1 of the project shows that improvements of 50-100% on the performance of a hybrid cooler can be achieved as compared to a dry cooler. The improvement is achieved by humidifying the air with recirculated water through nozzles so that the air temperature decreases from the dry temperature to the wet temperature, and that the dry cooler surface is humidified with a film of water, which increases the heat transfer coefficient considerably compared to a dry surface. The experiments showed that a humidifier system cannot be used without further action. At face velocities less than 5 m/s the humidification does not yield any improvement, and in some cases the heat transfer in a standard dry cooler is decreased. This is due to entrainment of not fully vaporized droplets which are deposited between the dry cooler fins and form bridges that block parts of the cooler. By modifying the surface characteristics with a coating, it will be possible to drain the water away so that no bridges are formed. The company Accoat, which makes special surfaces, will therefore be associated to phase 2 of the project. Another aspect that was evident in the tests, is the formation of biofilm on the heat exchanger surface, which can reduce performance by up to 25%. Biofilm can be prevented by treating the feed water, and therefore Danish Clean Water A/S associated to phase 2 of the project, as they produce water purification systems for biofouling decomposition. (LN)

  17. A 300 Hz high frequency thermoacoustically driven pulse tube cooler

    Institute of Scientific and Technical Information of China (English)

    ZHU ShangLong; YU GuoYao; ZHANG XiaoDong; DAI Wei; LUO ErCang; ZHOU Yuan

    2008-01-01

    This article introduces the latest progress of a 300 Hz thermoacoustically driven pulse tube cooler. Based on the experience of former experiments, improvements have been made in the standing-wave engine, pulse tube cooler and their coupling mechanism. An inlet pressure ratio of 1.248 was obtained with the mean pressure and heating power of 4.13 MPa and 1760 W, respectively. A lowest no-load temperature of 69.5 K has been reached under this condition. This is the first time for thermoacousti-cally driven pulse tube coolers to reach the temperature below 76 K with such a high frequency.

  18. Development of software for the thermohydraulic analysis of air coolers

    Directory of Open Access Journals (Sweden)

    Šerbanović Slobodan P.

    2003-01-01

    Full Text Available Air coolers consume much more energy compared to other heat exchangers due to the large fan power required. This is an additional reason to establish reliable methods for the rational design and thermohydraulic analysis of these devices. The optimal values of the outlet temperature and air flow rate are of particular importance. The paper presents a methodology for the thermohydraulic calculation of air cooler performances, which is incorporated in the "Air Cooler" software module. The module covers two options: cooling and/or condensation of process fluids by ambient air. The calculated results can be given in various ways ie. in the tabular and graphical form.

  19. Instrumentation Upgrades to TITAN's Cooler Penning Trap

    Science.gov (United States)

    Lascar, Daniel; Titan Collaboration

    2016-09-01

    The use of Highly Charged Ions (HCIs) is critical to improving the precision of Penning trap mass measurements of nuclides with half-lives substantially less than 100 ms, but the process of charge breeding imparts an unacceptably high energy spread to the ion bunch sent to TITAN's precision Penning trap for mass measurement. TITAN's Cooler PEnning Trap (CPET) at TRIUMF in Vancouver, Canada was designed to cool HCIs with a plasma of simultaneously trapped electrons. CPET is currently undergoing commissioning offline at TRIUMF. In order to prepare CPET for full operation, several technical challenges associated with the use of electrons in a strong magnetic field had to be overcome. First among these was the detection of electrons outside of CPET. A novel, thin charge-collecting detector was successfully developed. Known as the mesh detector, it is charge-agnostic and can be made effectively transparent to allow for the passage of any charged particle at the user's request. The second challenge, moving CPET's electron source off the central beam axis was overcome by the creation of an electron source which would allow for electron injection into CPET and the passage of cooled ions out of CPET. CPET's 7 T solenoid generates a stray field far outside of the magnet's central bore that forced the design of a set of electron injection optics that bend, steer and focus the beam in three dimensions. Results from the successful installation of these upgrades as well as a report on future work will be discussed. This work was partially supported by NSERC, the CFI and the DFG.

  20. Micromachined Active Magnetic Regenerator for Low Temperature Magnetic Coolers Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's future science missions to investigate the structure and evolution of the universe require highly efficient, very low temperature coolers for low noise...

  1. Lightweight Magnetic Cooler with a Reversible Circulator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's future missions to investigate the structure and evolution of the universe require highly-efficient, very low temperature coolers for low-noise detector...

  2. Lightweight Magnetic Cooler with a Reversible Circulator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's future missions to investigate the structure and evolution of the universe require highly efficient, very low temperature coolers for low-noise detector...

  3. Lightweight Superconducting Magnets for Low Temperature Magnetic Coolers Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's future science missions to investigate the structure and evolution of the universe require efficient, very low temperature coolers for low noise detector...

  4. Miniaturized Thermal-Cooler for IC Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal is submitted for research on using MEMS technology to make unique, highly reliable, miniaturized capillary pumped coolers in the application of Thermal...

  5. Performance study on primary gas coolers with horizontal tubes

    Energy Technology Data Exchange (ETDEWEB)

    Volkov, E.L.; Lekhter, V.I.; Gostev, Yu.A. [and others

    1992-12-31

    No. 1-bis coke-oven battery system at the Mariupol C&CW was equipped with primary gas coolers of horizontal-tube type. They consisted of three sections, with working surface areas in m{sup 2} of: I (bottom) 800 (middle) 800 and III (top) 600 respectively. The nominal water flow rate through each cooler was 600-720 m. The coolers were constantly irrigated with tar/water emulsions to remove scale deposits in the inter-tube space. The circulating water from the primary gas coolers is cooled in a e-section cooling tower (type 2VG) equipped with spray nozzles designed by the Dnepropetrovsk Chemical Technology Institute (nominal water throughput 3000 m{sup 3}/h). 1 tab.

  6. Micromachined Active Magnetic Regenerator for Low Temperature Magnetic Coolers Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's future science missions to investigate the structure and evolution of the universe require highly efficient, very low temperature coolers for low noise...

  7. MM&T for Linear Resonant Cooler. Volume 1

    Science.gov (United States)

    1988-02-16

    COOSS 16-S SUBJECT TERMS (COntInuf O on fri WUI( Rfe*"Gnr and identify 6) bloct ri.rmbe, FIELD GROUP j SUB. GRPI Li near-Resonant; Compressor; Stirling ...Cycle I i Free-Displacer Cooler; Regenerator IS. ABSTRACT (Con notuor on Forvermi if necorstwy mnd iden afr 67 Weorknufflep This final report...producibility and performance of the prototype linear-drive Stirling cycle cooler design established in a prior contract, 2) qualify the design to the target

  8. A digital energy control system for the LEAR electron cooler

    CERN Document Server

    Caspers, Fritz; Molinari, G; Ramos, U

    1993-01-01

    A feedback control system has been developed to correct any energy errors that may occur when operating the electron cooler on LEAR. Drifts and, above all, the space charge effects are the main sources of error. Error cancellation must be compatible with the pulsed mode of operation of the electron cooler so that the beam must be stabilized at the right energy before the end of the corresponding flat top is reached.

  9. Evaluation of Stirling cooler system for cryogenic CO2 capture

    OpenAIRE

    Song, Chun Feng; Kitamura, Yutaka; Li, Shu Hong

    2012-01-01

    In previous research, a cryogenic system based on Stirling coolers has been developed. In this work, the novel system was applied on CO2 capture from post-combustion flue gas and different process parameters (i.e. flow rate of feed gas, temperature of Stirling cooler and operating condition) were investigated to obtain the optimal performance (CO2 recovery and energy consumption). From the extensive experiments, it was concluded that the cryogenic system could realize CO2 capture without solv...

  10. Large-Scale Containment Cooler Performance Experiments under Accident Conditions

    Directory of Open Access Journals (Sweden)

    Ralf Kapulla

    2012-01-01

    Full Text Available Computational Fluid Dynamics codes are increasingly used to simulate containment conditions after various transient accident scenarios. This paper presents validation experiments, conducted in the frame of the OECD/SETH-2 project. These experiments address the combined effects of mass sources and heat sinks related to gas mixing and hydrogen transport within containment compartments. A wall jet interacts with an operating containment cooler located in the middle (M-configuration and the top (T-configuration of the containment vessel. The experiments are characterized by a 3-phase injection scenario. In Phase I, pure steam is injected, while in Phase II, a helium-steam mixture is injected. Finally, in Phase III, pure steam is injected again. Results for the M-configuration show helium stratification build up during Phase II. During Phase III, a positively buoyant plume emerging from the cooler housing becomes negatively buoyant once it reaches the helium-steam layer and continuously erodes the layer. For the M-configuration, a strong degradation of the cooler performance was observed during the injection of the helium/steam mixture (Phase II. For the T-configuration, we observe a mainly downwards acting cooler resulting in a combination of forced and natural convection flow patterns. The cooler performance degradation was much weaker compared with the M-configuration and a good mixing was ensured by the operation of the cooler.

  11. 46 CFR 119.422 - Integral and non-integral keel cooler installations.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Integral and non-integral keel cooler installations. 119... MACHINERY INSTALLATION Specific Machinery Requirements § 119.422 Integral and non-integral keel cooler... connections for a keel cooler installation. (e) Shutoff valves are not required for integral keel coolers. A...

  12. Tests of Four PT-415 Coolers Installed in the Drop-in Mode

    Energy Technology Data Exchange (ETDEWEB)

    Green, Michael A.; Wang, S.T.

    2008-07-08

    The superconducting magnets and absorbers for MICE will be cooled using PT415 pulse tube coolers. The cooler 2nd stage will be connected to magnets and the absorbers through a helium or hydrogen re-condensing system. It was proposed that the coolers be connected to the magnets in such a way that the cooler can be easily installed and removed, which permits the magnets to be shipped without the coolers. The drop-in mode requires that the cooler 1st stage be well connected to the magnet shields and leads through a low temperature drop demountable connection. The results of the PT415 drop-in cooler tests are presented.

  13. Sesame Street: Socialization by Surrogate.

    Science.gov (United States)

    Felsenthal, Norman A.

    This paper reviews some of the controversy surrounding "Sesame Street's" treatment of the socialization progress of preschool television viewers. Examined in detail are those portions of "Sesame Street" programs which contribute to children's learning of socially acceptable attitudes and behaviors. Some comparisons are made…

  14. The Regulation of Street Foods

    DEFF Research Database (Denmark)

    Forkour, John Boulard; Samuelsen, Helle; Yeboah, Eric Henry

    2017-01-01

    the challenges and negotiating strategies of regulators of street-vended foods in Ghana and analyses the implication for their relationship with street food vendors. The paper reveals that regulators operate in a context of limited resources, leading to a general feeling of neglect. In coping, regulators adopt...

  15. A mechanical cooler for dual-temperature applications

    Science.gov (United States)

    Gully, W.; Carrington, H.; Kiehl, W.; Byrne, Kevin

    1998-01-01

    Ball Aerospace has been developing Stirling cycle mechanical cryocoolers specifically for space applications. These coolers are special in that they are designed from the beginning for power efficiency, high reliability, and compatibility with sensitive instruments. We have delivered several of these coolers to NASA Goddard Space Flight Center, and are currently assembling one for the High Resolution Dynamics Limb Sounder (HIRDLS) program. In our current research effort, funded by the Ballistic Missile Defense Organization (BMDO), we are tailoring our basic design to new requirements from the Air Force Research Laboratory and its customers. We describe our success in optimizing a cooler to efficiently provide refrigeration at two different temperatures simultaneously. This two-temperature application requires 0.4 W of cooling at 35 K, and 0.6 W of cooling at 60 K. We have met these requirements with an input power of approximately 70 W from a dc source with a breadboard version of the cooler. We expect to deliver the protoflight version of this cooler to the Air Force Research Laboratory in January 1998.

  16. Micro-cooler enhancements by barrier interface analysis

    Energy Technology Data Exchange (ETDEWEB)

    Stephen, A.; Dunn, G. M. [Department of Physics, University of Aberdeen, King' s College, AB24 3UE Aberdeen (United Kingdom); Glover, J.; Oxley, C. H. [Department of Engineering, De Montfort University, Gateway, LE1 9BH Leicester (United Kingdom); Bajo, M. Montes; Kuball, M. [Center for Device Thermography and Reliability, H. H. Wills Physics Laboratory, University of Bristol, BS8 1TL Bristol (United Kingdom); Cumming, D. R. S.; Khalid, A. [School of Engineering, University of Glasgow, Rankine Building, G12 8LT Glasgow (United Kingdom)

    2014-02-15

    A novel gallium arsenide (GaAs) based micro-cooler design, previously analysed both experimentally and by an analytical Heat Transfer (HT) model, has been simulated using a self-consistent Ensemble Monte Carlo (EMC) model for a more in depth analysis of the thermionic cooling in the device. The best fit to the experimental data was found and was used in conjunction with the HT model to estimate the cooler-contact resistance. The cooling results from EMC indicated that the cooling power of the device is highly dependent on the charge distribution across the leading interface. Alteration of this charge distribution via interface extensions on the nanometre scale has shown to produce significant changes in cooler performance.

  17. Micro-cooler enhancements by barrier interface analysis

    Directory of Open Access Journals (Sweden)

    A. Stephen

    2014-02-01

    Full Text Available A novel gallium arsenide (GaAs based micro-cooler design, previously analysed both experimentally and by an analytical Heat Transfer (HT model, has been simulated using a self-consistent Ensemble Monte Carlo (EMC model for a more in depth analysis of the thermionic cooling in the device. The best fit to the experimental data was found and was used in conjunction with the HT model to estimate the cooler-contact resistance. The cooling results from EMC indicated that the cooling power of the device is highly dependent on the charge distribution across the leading interface. Alteration of this charge distribution via interface extensions on the nanometre scale has shown to produce significant changes in cooler performance.

  18. Exergoeconomic, enviroeconomic and sustainability analyses of a novel air cooler

    Energy Technology Data Exchange (ETDEWEB)

    Caliskan, Hakan [Department of Mechanical Engineering, Faculty of Engineering, Ege University (Turkey)], email: hakan.caliskan@ege.edu.tr; Dincer, Ibrahim [Faculty of Engineering and Applied Science, University of Ontario Institute of Technology (Canada)], email: Ibrahim.Dincer@uoit.ca; Hepbasli, Arif [Department of Mechanical Engineering, College of Engineering, King Saud University (Saudi Arabia)], email: ahepbasli.c@ksu.edu.sa

    2011-07-01

    With the energy crisis and the rising concerns about the environment, energy-saving measures are urgently needed. In the building sector, air conditioning systems consume important amounts of energy and a new evaporative air cooler system has been developed. This system is based on the Maisotsenko cycle and aims at providing comfortable indoor conditions for low energy consumption and with high efficiency. The objective of this paper is to present the analysis of the energy, exergy, environmental, exergoeconomic, enviroeconomic and sustainability performances of this novel air cooler. The different analyses were carried out for 9 dead state temperatures from 0 to 37.77 degree celsius. Results of all the different analyses performed are provided herein. This study provided useful information on the performance of the Maisotsenko cycle-based air cooler system and showed the originality of the system.

  19. New Regenerator Materials for use in pulse tube coolers

    Energy Technology Data Exchange (ETDEWEB)

    A. Kashani; B.P.M. Helvensteijn; P. Kittel; K.A. Gschneidner,jr; V.K. Pecharsky; A.O. Pecharsky

    2004-09-30

    A two-stage pulse tube cooler driven by a linear compressor is being developed to provide cooling at 20 K. The first stage of the cooler will have the conventional stainless steel screen regenerator matrix. The matrix for the second stage regenerator (<60 K) will be made from a new class of Er based alloys which was recently developed at Ames Laboratory, in Ames, Iowa. These alloys exhibit heat capacities that exceed that of all other materials, including lead, over a Wide range in temperature (15 K < T C 85 K). The performance of one such alloy was shown to be better than lead when tested in a single-stage pulse tube cooler driven by a G-M compressor and operating at 2 Hz. An effort is underway to establish their suitability at frequencies above 40 IIZ. An approach to testing these alloys at low temperatures while using a low-power linear compressor is presented.

  20. Violence in the Street, Violence of the Street

    DEFF Research Database (Denmark)

    Heinskou, Marie Bruvik; Liebst, Lasse Suonperä

    While in his early and general theory of interaction rituals Randall Collins emphasised that social situations are both ’symbolic’ and ’material’, the latter dimension is largely absent from Collins’ theory of violence(Collins 2004; 1993: 214). Compared with criminology’s more recent situational...... studies of violence, it is noticeable that the analytical success of these studies is closely linked with understanding street violence as a spatial-situational phenomenon (Clarke 1997; Eck & Weisburd 1995; Bragand & Weisburd; 2010; Wikström et al. 2012; Sampson et al. 1997). In light of evidence...... for the spatial concentration of street violence, this paper takes its point of departure in a large study of Street Violence among youth in Copenhagen, Denmark (combining quantitative data from filed police reports (N = 501), data from CCTV (N=100) and qualitative analysis of selected cases of street violence...

  1. USE OF PELTIER COOLERS AS SOIL HEAT FLUX TRANSDUCERS.

    Science.gov (United States)

    Weaver, H.L.; Campbell, G.S.

    1985-01-01

    Peltier coolers were modified and calibrated to serve as soil heat flux transducers. The modification was to fill their interiors with epoxy. The average calibration constant on 21 units was 13. 6 plus or minus 0. 8 kW m** minus **2 V** minus **1 at 20 degree C. This sensitivity is about eight times that of the two thermopile transducers with which comparisons were made. The thermal conductivity of the Peltier cooler transducers was 0. 4 W m** minus **1 degree C** minus **1, which is comparable to that of dry soil.

  2. Investigations of waste heat recovery from bulk milk cooler

    OpenAIRE

    S.N. Sapali; S.M. Pise; A.T. Pise; D.V. Ghewade

    2014-01-01

    Bulk milk coolers are used to chill the milk from its harvest temperature of 35–4 °C to arrest the bacterial growth and maintain the quality of harvested milk. Milk chilling practices are energy intensive with low coefficient of performance (COP) of about 3.0. Increased energy cost concern encouraged an investigation of heat recovery from bulk milk cooler as one conservation alternative for reducing water heating cost in dairy industry. Heat dissipated to atmosphere through condenser is recov...

  3. Electrocaloric cooler combining ceramic multi-layer capacitors and fluid

    Directory of Open Access Journals (Sweden)

    Daniele Sette

    2016-09-01

    Full Text Available In this paper, an electrocaloric (EC cooler prototype made of 150 ceramic-based Multi-Layer Capacitors (MLCs has been detailed. This cooler involves a column of dielectric fluid where heat exchange with the MLCs takes place. The maximum variation of temperature in the fluid column due to the EC effect reaches 0.13 K whereas the heat exchanged during one stroke is 0.28 J. Although this prototype requires improvements with respect to heat exchange, the basic principle of creating a temperature gradient in a column of fluid has been validated.

  4. Simulations of space charge neutralization in a magnetized electron cooler

    Energy Technology Data Exchange (ETDEWEB)

    Gerity, James [Texas A-M; McIntyre, Peter M. [Texas A-M; Bruhwiler, David Leslie [RadiaSoft, Boulder; Hall, Christopher [RadiaSoft, Boulder; Moens, Vince Jan [Ecole Polytechnique, Lausanne; Park, Chong Shik [Fermilab; Stancari, Giulio [Fermilab

    2017-02-02

    Magnetized electron cooling at relativistic energies and Ampere scale current is essential to achieve the proposed ion luminosities in a future electron-ion collider (EIC). Neutralization of the space charge in such a cooler can significantly increase the magnetized dynamic friction and, hence, the cooling rate. The Warp framework is being used to simulate magnetized electron beam dynamics during and after the build-up of neutralizing ions, via ionization of residual gas in the cooler. The design follows previous experiments at Fermilab as a verification case. We also discuss the relevance to EIC designs.

  5. Market Assessment and Commercialization Strategy for the Radial Sandia Cooler

    Energy Technology Data Exchange (ETDEWEB)

    Goetzler, William [Navigant Consulting, Inc., Burlington, MA (United States); Shandross, Richard [Navigant Consulting, Inc., Burlington, MA (United States); Weintraub, Daniel [Navigant Consulting, Inc., Burlington, MA (United States); Young, Jim [Navigant Consulting, Inc., Burlington, MA (United States)

    2014-02-01

    This market assessment and commercialization report characterizes and assesses the market potential of the rotating heat exchanger technology developed at Sandia National Laboratories (SNL), known as the Radial Sandia Cooler. The RSC is a novel, motor-driven, rotating, finned heat exchanger technology. The RSC was evaluated for the residential, commercial, industrial, and transportation markets. Recommendations for commercialization were made based on assessments of the prototype RSC and the Sandia Cooler technology in general, as well as an in-depth analysis of the six most promising products for initial RSC commercialization.

  6. Laser pumping of ions in a cooler buncher

    Energy Technology Data Exchange (ETDEWEB)

    Cheal, B., E-mail: bradley.cheal@manchester.ac.uk [University of Manchester (United Kingdom); Baczynska, K. [University of Birmingham, School of Physics and Astronomy (United Kingdom); Billowes, J.; Campbell, P. [University of Manchester (United Kingdom); Eronen, T. [University of Jyvaeskylae, Department of Physics (Finland); Forest, D. H. [University of Birmingham, School of Physics and Astronomy (United Kingdom); Kessler, T.; Moore, I. D. [University of Jyvaeskylae, Department of Physics (Finland); Rueffer, M. [University of Birmingham, School of Physics and Astronomy (United Kingdom); Tordoff, B. [University of Manchester (United Kingdom); Tungate, G. [University of Birmingham, School of Physics and Astronomy (United Kingdom); Aystoe, J. [University of Jyvaeskylae, Department of Physics (Finland)

    2008-01-15

    Optical experiments at the IGISOL isotope separator facility, Jyvaeskylae, have for many years benefited from the introduction of an ion beam cooler. The device, a gas-filled RF quadrupole, reduces the emittance and longitudinal energy spread of the ion beam. Very recently, use has been made of the axial confinement of slowly travelling ions at the end of the cooler to redistribute the electronic populations through efficient laser excitation. Such a technique has proved beneficial to laser spectroscopic measurements and is a precursor to using the method to polarize the ion beam.

  7. CoolerMaster COSMOS S运动版

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    说起前一年的顶级机箱,CoolerMaster COSMOS绝对要算一个。在2008年德国CeBIT展会上,CoolerMaster公司又在该作的基础上推出了COSMOS S运动版,在提供极致散热性能的同时,新的动感机身,触控式按键设计,让COSMOS有一种焕然如新的感觉。

  8. Molecular absorption cryogenic cooler for liquid hydrogen propulsion systems

    Science.gov (United States)

    Klein, G. A.; Jones, J. A.

    1982-01-01

    A light weight, long life molecular absorption cryogenic cooler (MACC) system is described which can use low temperature waste heat to provide cooling for liquid hydrogen propellant tanks for interplanetary spacecraft. Detailed tradeoff studies were made to evaluate the refrigeration system component interactions in order to minimize the mass of the spacecraft cooler system. Based on this analysis a refrigerator system mass of 31 kg is required to provide the .48 watts of cooling required by a 2.3 meter diameter liquid hydrogen tank.

  9. Young boys and street gangs

    DEFF Research Database (Denmark)

    Bruselius-Jensen, Maria; Pless, Mette

    of joining street gangs, this presentation demonstrates that, to the young boys, street gangs represent alternative societies that seems much more accessible than school and work communities. Street gangs seemingly gives access to social recognition and networks, economic opportunities and material status...... to the police sta- tion and a short police internship, show that the boys are very attracted to the police profession and find that it offers many of the same opportunities; network, recognition and thrills. Thus, indicating that, for the 40 boys, the line between civic and anti-civic participation can...

  10. Censura e street creativity

    Directory of Open Access Journals (Sweden)

    Edwige Comoy Fusaro

    2015-05-01

    Full Text Available Scopo di questo contributo è osservare la funzione seminale della censura nella street creativity e gli spostamenti dei confini tra lecito e illecito nei complessi rapporti tra censorship e creatività nell’ambiente urbano. Sono prese in considerazione tutte le produzioni iconografiche eseguite nello spazio pubblico, commissionate e non commissionate, qualunque siano i supporti prescelti e le tecniche di esecuzione, e  prescindendo da ogni giudizio estetico e artistico. Lo studio è basato su pezzi osservati in varie città d’Italia, Francia, Germania e Inghilterra nel 2014. Si prendono in considerazione la loro precisa collocazione, i motivi raffigurati e/o espressi e le motivazioni dei loro autori, quando sono note. Vari tipi di censura spingono i doers a esprimersi per strada: anzitutto la regolamentazione dell’occupazione visiva dell’ambiente urbano, le ingiunzioni e i divieti che emanano dai media autorizzati a occupare tale ambiente. I doers denunziano inoltre le menzogne delle autorità politiche, tramite rappresentazione delle verità censurate o azioni di artivism. All’origine del gesto espressivo di strada si trovano inoltre l’impulso trasgressivo, la volontà di comunicare con la gente e, soggiacente, la consapevolezza della caducità della vita.

  11. The Rehabilitation Paradox: Street-Working Children in Afghanistan

    Science.gov (United States)

    Williams, Christopher; Yazdani, Farzaneh

    2009-01-01

    International humanitarian intervention in Afghanistan reflects a policy discourse of "rehabilitation," which is very evident in relation to nongovernmental organization (NGO) projects for street-working children. Through analysing national and international policy, professional perceptions of the children, and field visits to see how…

  12. Sesame Street: Magic or Malevolence?

    Science.gov (United States)

    Ratliff, Anne R.; Ratliff, Richard G.

    1972-01-01

    Despite its unusual potential, both educational and social, it seems that Sesame Street may be exposing children to unnecessary aggression...(which) often goes unpunished and, occasionally, is actively rewarded." (Author)

  13. Yishui snow mountain Rainbow Valley business street space environment planning design and research

    Institute of Scientific and Technical Information of China (English)

    谭彦艳

    2015-01-01

    Yishui snow mountain Rainbow Valley is a tourist area of Linyi in Yishui, because Yishui beautiful scenery, a variety of tourism resources, tourism and commercial street is an important breakthrough in its development, to create a local cultural tourism based on the set of economic, culture, leisure, entertainment, which integrates comprehensive commercial street. This topic design follow the “taking culture made the street, taking history made the street, to the situation raises the street”. In the area of history culture as the foundation, the extraction of excellent design element is applied to the design of this project, join the history context elements, inheriting excellent historical culture, the rainbow door, snow capped mountains seventy-two king into the landscape design, reflect the local cultural characteristics of Yishui. The commercial street full of human feelings, the commercial street built with Yishui local characteristics and street full of personality. In the process of construction of commercial street, commercial street, the endowment of regional cultural resources, highlighting its cultural positioning, highlight the small town of Yishui regional culture, build a rich with Yishui town of local cultural characteristics and style commercial street.

  14. Status of the IUCF Cooler Injector Synchrotron Construction Project

    Science.gov (United States)

    Friesel, D. L.; Lee, S. Y.

    1997-05-01

    Construction of a 2.24 T-m, rapid-cycling booster synchrotron is nearing completion at IUCF. The synchrotron is designed to accelerate protons to 220 MeV and will replace the IUCF isochronous cyclotrons as an injector of polarized light ion beams into the 3.6 T-m electron-cooled storage ring. CIS (Cooler Injector Synchrotron), with a circumference of 1/5th the Cooler ring, will fill the Cooler to about 10^11 protons via ``boxcar" stacking in a few seconds for research. The compact booster design, which can accelerate protons to energies between 60 and 220 MeV, is also well suited for use in proton therapy applications. At 28 months into the construction program, all major ring elements (dipoles, quads, injector linac, RF system) are fabricated, assembled, installed and in some cases, commissioned. Ring beam injection and ramping studies are scheduled to start in May, 1997 and Cooler injection studies are planned for late 1997. The booster design properties, component commissioning results and construction completion schedule will be summarized.

  15. Space Charge Dominated Beams in the Iucf Cooler

    Science.gov (United States)

    Nagaitsev, Sergei

    1995-01-01

    Many present and future accelerator projects require significantly increased brightness of the accelerated and stored beams to make modern nuclear and high energy experiments feasible. In the case of IUCF Cooler it has been stated that there is strong motivation for increased beam intensity to provide the designed luminosity for the future Light Ion Spin Synchrotron. To achieve the desired brightness of the beam one must consider a complex problem involving both effective injection and circumventing various intensity limits. This dissertation is essentially a collection of theoretical models and experimental observations which, taken together, make an attempt to analyze numerous intensity and space charge related effects in the IUCF Cooler. We found that the proton beams in the IUCF Cooler are nearly completely space charge dominated longitudinally. This leads to a number of beam properties, such as coherent synchrotron frequency shift and an absence of decoherence in the synchrotron phase oscillations, which have not been observed before. We observed experimentally that the intensity limit in the IUCF Cooler is a peak current limit due to space charge effects. Beam losses occur due to incoherent transverse effects, such as large space charge tune shift and the formation of tails. In addition to that, a very precise bunched beam current monitor was invented and tested. This device could be used in the future precise nuclear experiments.

  16. Optimal digital control of a Stirling cycle cooler

    Science.gov (United States)

    Feeley, J.; Feeley, P.; Langford, G.

    1990-01-01

    This short paper describes work in progress on the conceptual design of a control system for a cryogenic cooler intended for use aboard spacecraft. The cooler will produce 5 watts of cooling at 65 K and will be used to support experiments associated with the following: earth observation; atmospheric measurements; infrared, x-ray, and gamma-ray astronomy; and magnetic field characterization. The cooler has been designed and constructed for NASA/GSFC by Philips Laboratories and is described in detail. The cooler has a number of unique design features intended to enhance long life and maintenance free operation in space including use of the high efficiency Stirling thermodynamic refrigeration cycle, linear magnetic motors, clearance-seals, and magnetic bearings. The proposed control system design is based on optimal control theory and is targeted for custom integrated circuit implementation. The resulting control system will meet the following mission requirements: efficiency, reliability, optimal thermodynamic, electrical, and mechanical performance; freedom from operator intervention; light weight; and small size.

  17. Commissioning of the LEIR electron cooler with Pb$^{+54}$ ions

    CERN Document Server

    Tranquille, G; Carly, Ch; Prieto, V; Sautier, R; Bubley, A; Parkhomchuk, V; Reva, V; Brizgunov, M; Vedenev, M; Panasyuk, V

    2006-01-01

    The new LEIR cooler with a variable profile of the electron beam and electrostatic bending was commissioned in 2005-2006. In this paper we present our experience with the commissioning of the new device as well as the first results of the ion beam Pb +54 cooling with a high-intensity variable-density electron beam.

  18. The effects of urban warming on herbivore abundance and street tree condition.

    Science.gov (United States)

    Dale, Adam G; Frank, Steven D

    2014-01-01

    Trees are essential to urban habitats because they provide services that benefit the environment and improve human health. Unfortunately, urban trees often have more herbivorous insect pests than rural trees but the mechanisms and consequences of these infestations are not well documented. Here, we examine how temperature affects the abundance of a scale insect, Melanaspis tenebricosa (Comstock) (Hemiptera: Diaspididae), on one of the most commonly planted street trees in the eastern U.S. Next, we examine how both pest abundance and temperature are associated with water stress, growth, and condition of 26 urban street trees. Although trees in the warmest urban sites grew the most, they were more water stressed and in worse condition than trees in cooler sites. Our analyses indicate that visible declines in tree condition were best explained by scale-insect infestation rather than temperature. To test the broader relevance of these results, we extend our analysis to a database of more than 2700 Raleigh, US street trees. Plotting these trees on a Landsat thermal image of Raleigh, we found that warmer sites had over 70% more trees in poor condition than those in cooler sites. Our results support previous studies linking warmer urban habitats to greater pest abundance and extend this association to show its effect on street tree condition. Our results suggest that street tree condition and ecosystem services may decline as urban expansion and global warming exacerbate the urban heat island effect. Although our non-probability sampling method limits our scope of inference, our results present a gloomy outlook for urban forests and emphasize the need for management tools. Existing urban tree inventories and thermal maps could be used to identify species that would be most suitable for urban conditions.

  19. The effects of urban warming on herbivore abundance and street tree condition.

    Directory of Open Access Journals (Sweden)

    Adam G Dale

    Full Text Available Trees are essential to urban habitats because they provide services that benefit the environment and improve human health. Unfortunately, urban trees often have more herbivorous insect pests than rural trees but the mechanisms and consequences of these infestations are not well documented. Here, we examine how temperature affects the abundance of a scale insect, Melanaspis tenebricosa (Comstock (Hemiptera: Diaspididae, on one of the most commonly planted street trees in the eastern U.S. Next, we examine how both pest abundance and temperature are associated with water stress, growth, and condition of 26 urban street trees. Although trees in the warmest urban sites grew the most, they were more water stressed and in worse condition than trees in cooler sites. Our analyses indicate that visible declines in tree condition were best explained by scale-insect infestation rather than temperature. To test the broader relevance of these results, we extend our analysis to a database of more than 2700 Raleigh, US street trees. Plotting these trees on a Landsat thermal image of Raleigh, we found that warmer sites had over 70% more trees in poor condition than those in cooler sites. Our results support previous studies linking warmer urban habitats to greater pest abundance and extend this association to show its effect on street tree condition. Our results suggest that street tree condition and ecosystem services may decline as urban expansion and global warming exacerbate the urban heat island effect. Although our non-probability sampling method limits our scope of inference, our results present a gloomy outlook for urban forests and emphasize the need for management tools. Existing urban tree inventories and thermal maps could be used to identify species that would be most suitable for urban conditions.

  20. STREET RHYMES AND THE AESTHETICS OF RESISTANCE

    Directory of Open Access Journals (Sweden)

    Rôssi Alves Gonçalves

    2015-12-01

    Full Text Available Rio de Janeiro is going through a sort of unique organization of the public environment, the rising of the social segments and culture antinarrative that, somehow, suffer from marginalization and exclusion. As means of rhymes, rappers (“MCs” are building a literary field, which creates tension on places of communication, culture, territorial appropriation, the city. It is a poetic production that requires reflection based on plural and distinct canonical tools that confronts its own concept of literature. The performance and the entire set which characterize such production are the starting point to comprehend the street rhymes aesthetically and politically. The aim of this article is to reflect upon urban literature, taking into account theorists like Homi Bhabha, Da Matta, Paul Zumthor, Stuart Hall.

  1. Initial Evaluation of a New Electromechanical Cooler for Safeguards Applications

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, RL

    2002-10-21

    The use of liquid nitrogen (LN{sub 2}) constitutes the current state of the art in cryogenic cooling for high-purity germanium (HPGe) detectors, which are widely used for {gamma}-ray and characteristic X-ray spectroscopy because of their excellent energy discrimination. Use of LN{sub 2} requires a liquid nitrogen supply, cumbersome storage tanks and plumbing, and the frequent attention of personnel to be sure that nitrogen levels are sufficient to maintain the detectors at a sufficiently low operating temperature. Safety hazards also are associated with the use of LN{sub 2}, both because of the potential for severe frostbite on exposure to skin and because it displaces ambient oxygen when it evaporates in closed spaces. Existing electromechanical coolers have, until now, been more expensive to procure and maintain than LN{sub 2} systems. Performance and reliability have also been serious issues because of microphonic degradation of photon energy peak resolution and cooler failures due to compressor oil becoming entrained in the refrigerant. This report describes the results of tests of a new HPGe detector cooling technology, the PerkinElmer ORTEC{reg_sign} Products X-Cooler{trademark} that, according to the manufacturer, significantly reduces the lifetime cost of the cooling system without degradation of the output signal. The manufacturer claims to have overcome cost, performance and reliability problems of older-generation electromechanical coolers, but the product has no significant history of use, and this project is the first independent evaluation of its performance for Total cost savings for the DOE and other agencies that use HPGe systems extensively for safeguards monitoring is expected to be quite significant if the new electromechanical cooler technology is shown to be reliable and if performance characteristics indicate its usefulness for this application. The technology also promises to make HPGe monitoring, characterization and detection available for

  2. Analisis Laju Pendinginan pada Kulkas Thermoelektrik Super Cooler Dibandingkan Sistem Pendingin Konvensional Menggunakan Gas Freon

    OpenAIRE

    Banjarnahor, Hendri Pronoto

    2016-01-01

    It has been designed and analyzed by using a cooling device which was have a Peltier cooler hot side and a cold side using a principle works of Peltier effect . These study analyze and compare the rate-based thermoelectric cooling refrigerator cooler than conventional cooling systems using freon gas. These study also focused on utilizing conventional refrigerator (Air Freon) that have been damaged as the peltier coolers. By using the DC fan on the cooler side to accelerate c...

  3. Fluid flow and heat transfer in Joule-Thomson coolers coupled with infrared detectors

    Science.gov (United States)

    Du, Bingyan; Jia, Weimin

    2011-08-01

    Joule-Thomson coolers have been widely used in infrared detectors with respect to compact, light and low cost. For self-regulating Joule-Thomson cooler, its performance is required to be improved with the development of higher mass and larger diameter of focal plane infrared detectors. Self-regulating Joule-Thomson coolers use a limited supply of high pressure gas to support the cooling of infrared detectors. In order to develop Joule-Thomson coolers with a given volume of stored gas, it is important to study on fluid flow and heat transfer of Joule-Thomson coolers coupled with infrared detectors, especially the starting time of Joule-Thomson coolers. A serial of experiments of Joule-Thomson coolers coupled with 128×128 focal plane infrared detectors have been carried out. The exchanger of coolers are made of a d=0.5mm capillary finned with a copper wire. The coolers are self-regulated by bellows and the diameters are about 8mm. Nitrogen is used as working gas. The effect of pressure of working gas has been studied. The relation between starting time and pressure of working gas is proved to fit exponential decay. Error analysis has also been carried. It is crucial to study the performance of Joule-Thomson coolers coupled with infrared detectors. Deeper research on Joule-Thomson coolers will be carried on to improve the Joule-Thomson coolers for infrared detectors.

  4. 46 CFR 182.422 - Integral and non-integral keel cooler installations.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Integral and non-integral keel cooler installations. 182... VESSELS (UNDER 100 GROSS TONS) MACHINERY INSTALLATION Specific Machinery Requirements § 182.422 Integral and non-integral keel cooler installations. (a) A keel cooler installation used for engine cooling...

  5. 46 CFR 128.430 - Non-integral keel cooler installations.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Non-integral keel cooler installations. 128.430 Section... MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Design Requirements for Specific Systems § 128.430 Non-integral keel cooler installations. (a) Each hull penetration for a non-integral keel cooler installation must...

  6. 46 CFR 169.608 - Non-integral keel cooler installations

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Non-integral keel cooler installations 169.608 Section... SCHOOL VESSELS Machinery and Electrical Internal Combustion Engine Installations § 169.608 Non-integral keel cooler installations (a) Hull penetrations for non-integral keel cooler installations must be made...

  7. The (Street) Art of Resistance

    DEFF Research Database (Denmark)

    Awad, Sarah H.; Wagoner, Brady; Glaveanu, Vlad Petre

    2017-01-01

    This chapter focuses on the interrelation between resistance, novelty and social change We will consider resistance as both a social and individual phenomenon, a constructive process that articulates continuity and change and as an act oriented towards an imagined future of different communities....... In this account, resistance is thus a creative act having its own dynamic and, most of all, aesthetic dimension. In fact, it is one such visibly artistic form of resistance that will be considered here, the case of street art as a tool of social protest and revolution in Egypt. Street art is commonly defined...... in sharp contrast with high or fine art because of its collective nature and anonymity, its different kind of aesthetics, and most of all its disruptive, ‘anti-social’ outcomes. With the use of illustrations, we will argue here that street art is prototypical of a creative form of resistance, situated...

  8. Sensation Seeking in Street Violence

    DEFF Research Database (Denmark)

    Heinskou, Marie Bruvik; Liebst, Lasse Suonperä

    Sensation seeking leads to violence—runs an influential hypothesis in the social scientific study of violent behavior. Although studies confirm that violence is sometimes structured by sensation-seeking motives, the literature seldom comments on the limits to this explanation of violence....... The present study examines the scale of violence motivated by sensation seeking and the degree to which there are several distinct forms of sensation seeking motives operative in violence, rather than a sensation-seeking motive in the singular. The study draws on a sample of situations from Copenhagen...... involving street violence, which are coded quantitatively and qualitatively. Our analysis shows that sensation seeking only seldom seems to play a role in the structuring of street violence. Moreover, the data indicate that sensation seeking finds expression in street violence situations in two different...

  9. Ionospheric current system accompanied by auroral vortex streets

    CERN Document Server

    Hiraki, Yasutaka

    2016-01-01

    High resolution optical measurements have revealed that a sudden brightening of aurora and its deformation from an arc-like to a vortex street structure appear just at the onset of substorm. The instability of Alfv$\\acute{\\rm e}$n waves reflected from the ionosphere has been studied by means of magnetohydrodynamic simulations in order to comprehend the formation of auroral vortex streets. Our previous work reported that an initially placed arc intensifies, splits, and deforms into a vortex street during a couple of minutes, and the prime key is an enhancement of the convection electric field. This study elaborated physics of the ionospheric horizontal currents related to the vortex street in the context of so-called Cowling polarization. One component is due to the perturbed electric field by Alfv$\\acute{\\rm e}$n waves, and the other is due to the perturbed electron density (or polarization) in the ionosphere. It was found that, when a vortex street develops, upward/downward pair currents in its leading/trail...

  10. Plasma-beam traps and radiofrequency quadrupole beam coolers.

    Science.gov (United States)

    Maggiore, M; Cavenago, M; Comunian, M; Chirulotto, F; Galatà, A; De Lazzari, M; Porcellato, A M; Roncolato, C; Stark, S; Caruso, A; Longhitano, A; Cavaliere, F; Maero, G; Paroli, B; Pozzoli, R; Romé, M

    2014-02-01

    Two linear trap devices for particle beam manipulation (including emittance reduction, cooling, control of instabilities, dust dynamics, and non-neutral plasmas) are here presented, namely, a radiofrequency quadrupole (RFQ) beam cooler and a compact Penning trap with a dust injector. Both beam dynamics studies by means of dedicated codes including the interaction of the ions with a buffer gas (up to 3 Pa pressure), and the electromagnetic design of the RFQ beam cooler are reported. The compact multipurpose Penning trap is aimed to the study of multispecies charged particle samples, primarily electron beams interacting with a background gas and/or a micrometric dust contaminant. Using a 0.9 T solenoid and an electrode stack where both static and RF electric fields can be applied, both beam transport and confinement operations will be available. The design of the apparatus is presented.

  11. Growth of Chrysomya megacephala (Fabricius) maggots in a morgue cooler.

    Science.gov (United States)

    Thevan, Kumara; Ahmad, Abu Hassan; Rawi, Che Salmah Md; Singh, Bhupinder

    2010-11-01

    In estimating the postmortem interval (PMI) using maggots obtained during autopsy, the forensic entomologist makes decisions regarding the effects of low-temperature storage of the body on the insects. In this case report, a corpse was found in an abandoned house in the residential area of Bukit Mertajam, Penang, Malaysia. The maggots were found to be alive inside the mouth of the deceased although the corpse had been in the morgue cooler for 12 days. The maggots were reared and identified as Chrysomya megacephala (Fabricius). The emerged adult flies were kept as a stock colony, and the duration of development under the indoor fluctuating temperature regime was studied. The total duration of developmental process of this species was 9.5 ± 0.5 days, and the PMI estimated was 3.2 ± 0.6 days. This case report demonstrates the survival of Ch. megacephala maggots for 12 days and their growth inside the morgue cooler.

  12. SEXUAL BEHAVIOR OF STREET CHILDREN.

    Science.gov (United States)

    Stojadinović, Aleksandra; Batrnek Antonić, Daliborka; Perinović, Marija; Rončević, Nevenka

    2015-01-01

    Street children and youth are at risk of getting engaged in different behaviors including risky sexual behavior, which adversely affects their development and health. The aim of this study was to examine sexual behavior of street children and youth, and the risks and consequences associated with sexual behavior. A pilot study was conducted on a sample of 50 users of the Drop-in Centre for Street Children in Novi Sad, from 10 to 19 years of age. The study was conducted by a psychologist through structured interviews, with prior consent of the adolescent and parent. Among the respondents who were sexually active, 41.2% had had the first sexual intercourse by the age of 12, their median age at that time being 14 years, while the age at the time of the first sexual intercourse is 16 years in the general population of Serbia. The majority of sexually active adolescents had several partners, one male adolescent had sex with a person of the same sex, and one was paid for sex. Very few respondents used a condom. Among 15 male sexually active respondents, three (ages 11, 12 and 14) were forced to have unwanted sexual intercourse, and a quarter of adolescents (three boys and one girl) were forced to do something unwanted during sex. Despite a small and unrepresentative sample, the results of this study indicate serious problems and significant risks associated with sexual behavior of children and young people who live and work in streets. This pilot study suggests that it is necessary to conduct new research on sexual behavior of street children and youth on a representative sample and with appropriate methodology. The results of a new study should be used to plan and carry out appropriate preventive measures regarding sexual behavior of street children.

  13. Vortex Pressure-Reducing Desuperheating Plants and Steam Coolers

    Directory of Open Access Journals (Sweden)

    V. Kascheev

    2012-01-01

    Full Text Available The authors have developed and tested the entire device class that appeared as a result of fundamental investigations of multiphase flows in centrifugal force fields, understanding of process mechanism occurring in them and their mathematical description for optimization. Method for reduction of pressure and steam temperature in vortex pressure-reducing desuperheating plants and steam coolers has been proposed for the first time in the paper.

  14. Rahoitusselvitys aloittelevalle pk-yritykselle : Case: Pets Cooler

    OpenAIRE

    Uotinen, Emmi

    2013-01-01

    Tarkoituksena oli selvittää erilaisia rahoitusvaihtoehtoja aloittelevalle pienelle ja keskisuurelle yritykselle. Opinnäytetyön tavoite oli helpottaa toimeksiantajayrityksen Pets Cooler rahoituslähteiden valintaa. Yritystoiminnan on tarkoitus käynnistyä mahdollisimman nopeasti, ja selvitys on tukena aloituksessa. Toimeksiantaja halusi käsiteltävän myös kansainvälisen liiketoiminnan rahoitusta. Vienti ja mahdollisesti myös ulkomailla tapahtuva tuotanto on yrityksen haaveena tulevaisuudessa. ...

  15. Addressing Water Consumption of Evaporative Coolers with Greywater

    OpenAIRE

    Sahai, Rashmi

    2013-01-01

    Evaporative coolers (ECs) provide significant gains in energy efficiency compared to vapor compression air conditioners, but simultaneously have significant onsite water demand. This can be a major barrier to deployment in areas of the world with hot and arid climates. To address this concern, this study determined where in the world evaporative cooling is suitable, the water consumption of ECs in these cities, and the potential that greywater can be used reduce the consumption of potable wat...

  16. Numerical simulation of a semi-indirect evaporative cooler

    Energy Technology Data Exchange (ETDEWEB)

    Martin, R. Herrero [Departamento de Ingenieria Termica y de Fluidos, Universidad Politecnica de Cartagena, C/Dr. Fleming, s/n (Campus Muralla), 30202 Cartagena, Murcia (Spain)

    2009-11-15

    This paper presents the experimental study and numerical simulation of a semi-indirect evaporative cooler (SIEC), which acts as an energy recovery device in air conditioning systems. The numerical simulation was conducted by applying the CFD software FLUENT implementing a UDF to model evaporation/condensation. The numerical model was validated by comparing the simulation results with experimental data. Experimental data and numerical results agree for the lower relative humidity series but not for higher relative humidity values. (author)

  17. Cooler storage ring accomplished at heavy ion facility in Lanzhou

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The Heavy Ion Research Facility in Lanzhou-Cooler Storage Ring (HIRFLCSR),a flagship facility of basic research in China,passed the acceptance check under auspices of the State Development and Reform Commission on 30 July in Lanzhou,capital of Gansu Province.The event was jointly presided over by the Commission's Vice Minister ZHANG Xiaoqian and CAS Executive Vice President BAI Chunli.

  18. Street Papers, Work, and Begging

    DEFF Research Database (Denmark)

    Cockburn, Patrick Joseph

    2014-01-01

    Street papers are publications produced specifically for sale by the homeless and other vulnerable people in many countries around the world. Their social status is, however, often conspicuously unstable: ‘Get a job!’ has been reported as a common insult addressed to vendors, and street paper...... organisations have responded with their own rhetoric and strategies that aim at disrupting any analogy with begging. The present analysis frames these rhetorical confrontations as a struggle over economic legitimacy, highlighting some of the ways in which social actors build and sever the normatively...

  19. Six Sigma methods applied to cryogenic coolers assembly line

    Science.gov (United States)

    Ventre, Jean-Marc; Germain-Lacour, Michel; Martin, Jean-Yves; Cauquil, Jean-Marc; Benschop, Tonny; Griot, René

    2009-05-01

    Six Sigma method have been applied to manufacturing process of a rotary Stirling cooler: RM2. Name of the project is NoVa as main goal of the Six Sigma approach is to reduce variability (No Variability). Project has been based on the DMAIC guideline following five stages: Define, Measure, Analyse, Improve, Control. Objective has been set on the rate of coolers succeeding performance at first attempt with a goal value of 95%. A team has been gathered involving people and skills acting on the RM2 manufacturing line. Measurement System Analysis (MSA) has been applied to test bench and results after R&R gage show that measurement is one of the root cause for variability in RM2 process. Two more root causes have been identified by the team after process mapping analysis: regenerator filling factor and cleaning procedure. Causes for measurement variability have been identified and eradicated as shown by new results from R&R gage. Experimental results show that regenerator filling factor impacts process variability and affects yield. Improved process haven been set after new calibration process for test bench, new filling procedure for regenerator and an additional cleaning stage have been implemented. The objective for 95% coolers succeeding performance test at first attempt has been reached and kept for a significant period. RM2 manufacturing process is now managed according to Statistical Process Control based on control charts. Improvement in process capability have enabled introduction of sample testing procedure before delivery.

  20. Storage-ring Electron Cooler for Relativistic Ion Beams

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Fanglei [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Derbenev, Yaroslav [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Douglas, David R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Guo, Jiquan [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Johnson, Rolland P. [Muons Inc., Batavia, IL (United States); Krafft, Geoffrey A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Morozov, Vasiliy [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Zhang, Yuhong [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-05-01

    Application of electron cooling at ion energies above a few GeV has been limited due to reduction of electron cooling efficiency with energy and difficulty in producing and accelerating a high-current high-quality electron beam. A high-current storage-ring electron cooler offers a solution to both of these problems by maintaining high cooling beam quality through naturally-occurring synchrotron radiation damping of the electron beam. However, the range of ion energies where storage-ring electron cooling can be used has been limited by low electron beam damping rates at low ion energies and high equilibrium electron energy spread at high ion energies. This paper reports a development of a storage ring based cooler consisting of two sections with significantly different energies: the cooling and damping sections. The electron energy and other parameters in the cooling section are adjusted for optimum cooling of a stored ion beam. The beam parameters in the damping section are adjusted for optimum damping of the electron beam. The necessary energy difference is provided by an energy recovering SRF structure. A prototype linear optics of such storage-ring cooler is presented.

  1. Digital control of magnetic bearings in a cryogenic cooler

    Science.gov (United States)

    Feeley, J.; Law, A.; Lind, F.

    1990-01-01

    This paper describes the design of a digital control system for control of magnetic bearings used in a spaceborne cryogenic cooler. The cooler was developed by Philips Laboratories for the NASA Goddard Space Flight Center. Six magnetic bearing assemblies are used to levitate the piston, displacer, and counter-balance of the cooler. The piston and displacer are driven by linear motors in accordance with Stirling cycle thermodynamic principles to produce the desired cooling effect. The counter-balance is driven by a third linear motor to cancel motion induced forces that would otherwise be transmitted to the spacecraft. An analog control system is currently used for bearing control. The purpose of this project is to investigate the possibilities for improved performance using digital control. Areas for potential improvement include transient and steady state control characteristics, robustness, reliability, adaptability, alternate control modes, size, weight, and cost. The present control system is targeted for the Intel 80196 microcontroller family. The eventual introduction of application specific integrated circuit (ASIC) technology to this problem may produce a unique and elegant solution both here and in related industrial problems.

  2. Performance evaluation of indirect evaporative cooler using clay pot

    Science.gov (United States)

    Ramkumar, R.; Ragupathy, A.

    2016-05-01

    The aim of the experimental study is to investigate the performance of indirect evaporator cooler in hot and humid regions. A novel approach is implemented in the cooler using clay pot with different position (single, double and three pots) and different orientation as aligned and staggered position for potential and feasibility study. The clay pot is the ceramic material where the water filled inside the pot and due to the property of porosity, the water comes outer surface of the pot and contact with the air passing over the pot surface and air get cooled. A test rig was designed and fabricated to collect experimental data. The clay pots were arranged in aligned and staggered position. In our study heat transfer was analysed with various air velocity of 1m/s to 5m/s. The air temperature, relative humidity, pressure drop and effectiveness were measured and the performance of the evaporative cooler was evaluated. The analysis of the data indicated that cooling effectiveness improve with decrease of air velocity at staggered position. It was shown that staggered position has the higher performance (57%) at 1 m/s air velocity comparison with aligned position values at three pots position.

  3. 6D “Garren” snake cooler and ring cooler for µ{sup ±} cooling of a muon collider

    Energy Technology Data Exchange (ETDEWEB)

    Ding, X., E-mail: xding@bnl.gov [UCLA, Los Angeles, CA 90095 (United States); Berg, J.S. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Cline, D. [UCLA, Los Angeles, CA 90095 (United States); Garren, Al [Particle Beam Lasers, Inc., Northridge, CA 91324 (United States); Kirk, H.G. [Brookhaven National Laboratory, Upton, NY 11973 (United States)

    2014-12-21

    Six dimensional cooling of large emittance µ{sup +} and µ{sup −} beams is required in order to obtain the desired luminosity for a muon collider. In our previous study, we demonstrated that a 6D “Garren” ring cooler using both dipoles and solenoids in four 90{sup 0} achromatic arcs can give substantial cooling in all six phase space dimensions. In this paper, we describe the injection/extraction requirements of this four-sided ring. We also present the performance of an achromat-based 6D “Garren” snake cooler. The achromatic design permits the design to easily switch between a closed ring and a snaking geometry on injection or extraction from the ring.

  4. Dry coolers and air-condensing units (Review)

    Science.gov (United States)

    Milman, O. O.; Anan'ev, P. A.

    2016-03-01

    The analysis of factors affecting the growth of shortage of freshwater is performed. The state and dynamics of the global market of dry coolers used at electric power plants are investigated. Substantial increase in number and maximum capacity of air-cooled condensers, which have been put into operation in the world in recent years, are noted. The key reasons facilitating the choice of developers of the dry coolers, in particular the independence of the location of thermal power plant from water sources, are enumerated. The main steam turbine heat removal schemes using air cooling are considered, their comparison of thermal efficiency is assessed, and the change of three important parameters, such as surface area of heat transfer, condensate pump flow, and pressure losses in the steam exhaust system, are estimated. It is shown that the most effective is the scheme of direct steam condensation in the heat-exchange tubes, but other schemes also have certain advantages. The air-cooling efficiency may be enhanced much more by using an air-cooling hybrid system: a combination of dry and wet cooling. The basic applied constructive solutions are shown: the arrangement of heat-exchange modules and the types of fans. The optimal mounting design of a fully shopassembled cooling system for heat-exchange modules is represented. Different types of heat-exchange tubes ribbing that take into account the operational features of cooling systems are shown. Heat transfer coefficients of the plants from different manufacturers are compared, and the main reasons for its decline are named. When using evaporative air cooling, it is possible to improve the efficiency of air-cooling units. The factors affecting the faultless performance of dry coolers (DC) and air-condensing units (ACU) and the ways of their elimination are described. A high velocity wind forcing reduces the efficiency of cooling systems and creates preconditions for the development of wind-driven devices. It is noted that

  5. Diverse risks, diverse perpetrators: perceptions of risk and experiences of violence amongst street-based sex workers in New Zealand

    OpenAIRE

    Lynzi Armstrong

    2014-01-01

    The management of violence-related risks on the street invariably relates to individual perceptions of violence amongst street-based sex workers. This paper explores perceptions and experiences of violence amongst street-based sex workers in Wellington and Christchurch. This paper begins with an overview of how risks of violence have been conceptualised and how the diversity of these risks is reflected in the perceptions and experiences of the women interviewed. Some complexities in how these...

  6. Acoustic characteristics of urban streets in relation to scattering caused by building facades

    DEFF Research Database (Denmark)

    Onaga, Hiroshi; Rindel, Jens Holger

    2007-01-01

    The relationship between scattering and the acoustic characteristics of urban streets is examined by computer simulation. The simulation method is a combination of the image method for specular reflection and the radiosity method for scattering reflection. The findings are as follows: (1) the eff......The relationship between scattering and the acoustic characteristics of urban streets is examined by computer simulation. The simulation method is a combination of the image method for specular reflection and the radiosity method for scattering reflection. The findings are as follows: (1...

  7. Wary Eyes Monitoring Wall Street

    Science.gov (United States)

    Jacobson, Linda

    2008-01-01

    School business officials kept a close watch on the financial markets this week--and on district investment portfolios and teacher-retirement funds--as stock prices gyrated and once-sound institutions got government bailouts or crumbled into bankruptcy. While financial observers said it was too soon to predict how Wall Street's upheaval might…

  8. Wary Eyes Monitoring Wall Street

    Science.gov (United States)

    Jacobson, Linda

    2008-01-01

    School business officials kept a close watch on the financial markets this week--and on district investment portfolios and teacher-retirement funds--as stock prices gyrated and once-sound institutions got government bailouts or crumbled into bankruptcy. While financial observers said it was too soon to predict how Wall Street's upheaval might…

  9. Youth and the City Streets.

    Science.gov (United States)

    Husby, Lynn; Brendtro, Larry

    1992-01-01

    This "Voices of Pioneers" section of the journal highlights the work of Jane Addams, who founded the settlement house movement in America with the establishment of Hull House in Chicago in 1899. Presents excerpts from Addams' book "The Spirit of Youth and the City Streets (1909)" to illustrate her views on guns, stealing, rebellion, and drugs. (NB)

  10. Youth and the City Streets.

    Science.gov (United States)

    Husby, Lynn; Brendtro, Larry

    1992-01-01

    This "Voices of Pioneers" section of the journal highlights the work of Jane Addams, who founded the settlement house movement in America with the establishment of Hull House in Chicago in 1899. Presents excerpts from Addams' book "The Spirit of Youth and the City Streets (1909)" to illustrate her views on guns, stealing,…

  11. Street Rhymes around the World.

    Science.gov (United States)

    Yolen, Jane, Ed.

    Based on the idea that although children of every nation speak different languages the language of play is international, this collection of 32 street rhymes from 17 nations and republics offers each rhyme in its native language (Portuguese, Tamil, Hebrew, Japanese, Russian, Chinese, Spanish, Greek, German, Bantu (Mambwe), Danish, Cheyenne,…

  12. Street photography as social interaction

    Directory of Open Access Journals (Sweden)

    Andrea Mubi Brighenti

    2009-06-01

    Full Text Available Street photographers know quite well that taking a picture is a form of social interaction. The birth of this genre of photography, they have been discussing at length about the ethical problems involved in taking pictures of personal strangers in public places without asking permission.

  13. Red lantern Streets- Chinese Style

    Institute of Scientific and Technical Information of China (English)

    INESAPLESKACHEUSKAYA

    2005-01-01

    WHEN speaking of ""red lantern streets,""what's the first thing that comes to mind?Sordid alleys, haunted by ladies of the night? While ""red lantern districts"" both in the East and the West have something in common, pleasures here in China are purely gastronomical in nature.

  14. COMMON GROUNDS BETWEEN PRINTMAKING AND STREET ART

    National Research Council Canada - National Science Library

    Balamber, Burcak

    2016-01-01

    ... to street based artists such as Keith Haring and Jean-Michel Basquiat entering to the galleries, and transformed into an artistic manner of expression having aesthetic concerns by adopting a more inclusive definition ‘street art...

  15. "Moving On": Learning to Cross Streets Independently.

    Science.gov (United States)

    Pattavina, Sylvia; And Others

    1992-01-01

    A 12-year-old boy with severe disabilities was taught street-crossing skills through the use of photographs with verbal rehearsal of appropriate street crossing, followed by community-based instruction. The skills were acquired, maintained at follow up, and generalized to new streets. (JDD)

  16. Street art - vandalismus nebo umění?

    OpenAIRE

    Grabmüllerová, Eva

    2012-01-01

    The diploma thesis ‚Street Art - Vandalism or Art?' deals with a world-wide phenomenon of contemporary art. The thesis focuses on the characterization of street art and history of street art (its origin and development) and analyzes the difference between street art and graffiti. The thesis presents street art techniques as well as notable street artists. The thesis also observes street art scene in the Czech Republic and depicts features that street art has in common with other art movements...

  17. Laser spectroscopy of gallium isotopes using the ISCOOL RFQ cooler

    CERN Multimedia

    Blaum, K; Kowalska, M; Ware, T; Procter, T J

    2007-01-01

    We propose to study the radioisotopes of gallium (Z=31) by collinear laser spectroscopy using the ISCOOL RFQ ion cooler. The proposed measurements on $^{62-83}$Ga will span both neutron-deficient and neutron-rich isotopes. Of key interest is the suggested development of a proton-skin in the neutron-deficient isotopes. The isotope shifts measured by laser spectroscopy will be uniquely sensitive to this feature. The measurements will also provide a wealth of new information on the gallium nuclear spins, static moments and nuclear charge radii.

  18. Integral finned heater and cooler for stirling engines

    Science.gov (United States)

    Corey, John A.

    1984-01-01

    A piston and cylinder for a Stirling engine and the like having top and bottom meshing or nesting finned conical surfaces to provide large surface areas in close proximity to the working gas for good thermal (addition and subtraction of heat) exchange to the working gas and elimination of the usual heater and cooler dead volume. The piston fins at the hot end of the cylinder are perforated to permit the gas to pass into the piston interior and through a regenerator contained therein.

  19. Test of a Sub-4K Mechanical Cooler for IXO and Other Space Based Sensors

    Science.gov (United States)

    Petach, Michael B.; Casement, L.; Michaelian, M.; Nguyen, T.; Raab, J.; Tward, E.

    2009-01-01

    X-ray Microcalorimeter Spectrometer Sensors on missions such as the International X-ray Observatory (IXO) require cooling to temperatures around 50mK to achieve the required sensitivity in the 0.6-10 keV band. Cooling an X-ray Sensor such as a Transition Edge Sensor (TES) to 50mK without the limitations on lifetime, mass, volume and reliability penalties of stored cryogen systems can be achieved with a multiple stage mechanical cryocooler. While no single cryocooler technology is appropriate for all of the stages, a hybrid cryocooler can be used. Fortunately, three cooler technologies that are each optimized for efficiency over the appropriate parts of the temperature range are rapidly maturing. For the lowest temperature stage, an Adiabatic Demagnetization Refrigerators (ADR) efficiently cools between 50mK and 2K to 4K. Next, a helium Joule Thomson cooler can efficiently pump the heat to 14K. Finally, a multistage pulse tube cooler efficiently pumps the heat from 14K to 300K. An existing ADR cooler, such as that demonstrated by NASA Goddard to TRL 5, can be cooled by a hybrid JT and pulse tube cooler similar to the cooler that NGST is building for the JWST/MIRI instrument, if its temperature is lowered from 6K to below 4K. The MIRI cooler leverages extensive NGST cooler heritage with >60 years of on-orbit performance with 11 pulse tube coolers currently operating continuously in orbit without failure. In this poster we present test results of a laboratory demonstration JT cooler stage with the sub-4K temperatures needed by the ADR cooler. By basing the test on the 6 K cooler technologies developed for the JWST MIRI program, the current development program provides the next step to reach the goal of TRL6 in time to support the IXO mission. This successful test provides demonstration of TRL 4 for the missing components required for an IXO cooler.

  20. COMMON GROUNDS BETWEEN PRINTMAKING AND STREET ART

    Directory of Open Access Journals (Sweden)

    Burcak Balamber

    2016-09-01

    Full Text Available Graffiti movement, born as a result of an effort of the youth, who felt themselves socially excluded and alone, to show their existence and identities during the 1960s, expanded its scope owing to street based artists such as Keith Haring and Jean-Michel Basquiat entering to the galleries, and transformed into an artistic manner of expression having aesthetic concerns by adopting a more inclusive definition ‘street art’. During this transformation of street art,street artists experimented with various methods from many different disciplines and hence created works in a wide range of varieties in terms of plastic and artistic values. Among these disciplines, printmakinghastaken its own place in street artas a discipline thatdeeply influenced street artists.Printmaking has fascinated street artists and become a part of their production process, not only with its philosophy sharing common grounds with street art and advantages in terms of its tecnical practices but also its unique plastic and linear values.Thanks to the opportunities of printmaking, street art has succeeded creating a tremendous impression worldwide, and even positioned itself into today’s greatest museums/gallery halls. This article aims to show how and in what way printmaking has influenced street art being in a transformation since the 1960s, and to put an emphasis on theimportance of printmaking on today’s street art.

  1. ADDITIONAL STREET BERBASIS APP INVENTOR

    Directory of Open Access Journals (Sweden)

    Mohammad Adib Adhi Prabowo

    2013-05-01

    Full Text Available Abstrak Seiring dengan perkembangan sistem operasi android, telah banyak aplikasi yang memanfaatkan fasilitas GPS dan Google Map, seperti untuk mencari rute, mendapatkan peta, mencari lokasi tertentu pada sebuah tempat. Akan tetapi seringkali pengguna perangkat bergerak kesulitan ketika ingin mengetahui beberapa tempat dan lokasi tertentu karena belum ada fasilitas yang menyediakan informasi lokasi suatu tempat. Walaupun ada informasi lokasi pada peta biasanya informasi yang diberikan lokasi tempat berskala besar, misalnya lokasi tempat wisata atau stasiun kereta api. Pengembangan aplikasi untuk skala kecil ini akan memberikan informasi yang dipresentasikan pada google map. Selama ini belum ada yang memberikan sebuah informasi lokasi tempat penting yang berskala kecil. Misalnya informasi lokasi  tambal ban, lokasi warung makan, lokasi laundry, dan lokasi bengkel motor. Oleh karena itu kami mencoba untuk mengembangkan aplikasi additional street berbasis android via App Inventor dengan bantuan google maps. Aplikasi additional street ini dapat memberikan informasi letak objek pada peta serta memberikan informasi jalan menuju lokasi tersebut dan detail informasi lokasi tersebut serta lokasi dari pengguna aplikasi tersebut. Kata Kunci: additional street, android, google maps, app inventor, GPS

  2. Promotion and Protection of the Rights of the Children in Street Situations in Bankok, Thailand

    OpenAIRE

    Wandee, Siripan

    2013-01-01

    This thesis aims at describing how the Convention on the Rights of the Child (CRC) is reflected in the overall operation of the Non-Governmental Organizations and government agencies working with children in street situations in Bangkok, Thailand. It describes children in different street situations in Bangkok; intervention approaches and working methods of the agencies that provide the services for them as well as similarities and differences in each group of the children. As the CRC sets a ...

  3. Investigations of waste heat recovery from bulk milk cooler

    Directory of Open Access Journals (Sweden)

    S.N. Sapali

    2014-11-01

    Full Text Available Bulk milk coolers are used to chill the milk from its harvest temperature of 35–4 °C to arrest the bacterial growth and maintain the quality of harvested milk. Milk chilling practices are energy intensive with low coefficient of performance (COP of about 3.0. Increased energy cost concern encouraged an investigation of heat recovery from bulk milk cooler as one conservation alternative for reducing water heating cost in dairy industry. Heat dissipated to atmosphere through condenser is recovered to improve the energy efficiency of plant. The waste heat is utilized to heat the water which is used to clean the milk processing equipments thus saving thermal or electrical energy used to heat the water separately. Shell and coil type heat exchanger is designed and used to recover the waste heat during condensation process. Heat rejected in condensation process consists of superheat and latent heat of the refrigerant. In this work, attempt has been made to recover complete superheat along with part of latent heat which is a present research issue. The results show that complete superheat and 35% of latent heat is recovered. Heat recovery rate is measured for various mass flow rates. Water is flowing on shell side and refrigerant through tubes. The effectiveness of the heat exchanger is determined and the results achieved are presented in this paper. Significant improvements have been achieved and COP of the system is increased from 3 to 4.8.

  4. CFD modeling of thermoelectric generators in automotive EGR-coolers

    Science.gov (United States)

    Högblom, Olle; Andersson, Ronnie

    2012-06-01

    A large amount of the waste heat in the exhaust gases from diesel engines is removed in the exhaust gas recirculation (EGR) cooler. Introducing a thermoelectric generator (TEG) in an EGR cooler requires a completely new design of the heat exchanger. To accomplish that a model of the TEG-EGR system is required. In this work, a transient 3D CFD model for simulation of gas flow, heat transfer and power generation has been developed. This model allows critical design parameters in the TEG-EGR to be identified and design requirements for the systems to be specified. Besides the prediction of Seebeck, Peltier, Thomson and Joule effects, the simulations also give detailed insight to the temperature gradients in the gas-phase and inside the thermoelectric (TE) elements. The model is a very valuable tool to identify bottlenecks, improve design, select optimal TE materials and operating conditions. The results show that the greatest heat transfer resistance is located in the gas phase and it is critical to reduce this in order to achieve a large temperature difference over the thermoelectric elements without compromising on the maximum allowable pressure drop in the system. Further results from an investigation of the thermoelectric performance during a vehicle test cycle is presented.

  5. Storage-ring Electron Cooler for Relativistic Ion Beams

    CERN Document Server

    Lin, F; Douglas, D; Guo, J; Johnson, R P; Krafft, G; Morozov, V S; Zhang, Y

    2016-01-01

    Application of electron cooling at ion energies above a few GeV has been limited due to reduction of electron cooling efficiency with energy and difficulty in producing and accelerating a high-current high-quality electron beam. A high-current storage-ring electron cooler offers a solution to both of these problems by maintaining high cooling beam quality through naturally-occurring synchrotron radiation damping of the electron beam. However, the range of ion energies where storage-ring electron cooling can be used has been limited by low electron beam damping rates at low ion energies and high equilibrium electron energy spread at high ion energies. This paper reports a development of a storage ring based cooler consisting of two sections with significantly different energies: the cooling and damping sections. The electron energy and other parameters in the cooling section are adjusted for optimum cooling of a stored ion beam. The beam parameters in the damping section are adjusted for optimum damping of the...

  6. Solar-Powered Cooler and Heater for an Automobile Interior

    Science.gov (United States)

    Howard, Richard T.

    2006-01-01

    The apparatus would include a solar photovoltaic panel mounted on the roof and a panellike assembly mounted in a window opening. The window-mounted assembly would include a stack of thermoelectric devices sandwiched between two heat sinks. A fan would circulate interior air over one heat sink. Another fan would circulate exterior air over the other heat sink. The fans and the thermoelectric devices would be powered by the solar photovoltaic panel. By means of a double-pole, double-throw switch, the panel voltage fed to the thermoelectric stack would be set to the desired polarity: For cooling operation, the chosen polarity would be one in which the thermoelectric devices transport heat from the inside heat sink to the outside one; for heating operation, the opposite polarity would be chosen. Because thermoelectric devices are more efficient in heating than in cooling, this apparatus would be more effective as a heater than as a cooler. However, if the apparatus were to include means to circulate air between the outside and the inside without opening the windows, then its effectiveness as a cooler in a hot, sunny location would be increased.

  7. Tuned dynamic absorber for split Stirling cryogenic cooler

    Science.gov (United States)

    Veprik, Alexander; Tuito, Avi

    2016-05-01

    Tuned dynamic absorbers (TDA) find use, in particular, for attenuating tonal vibration export produced by the moving components of cryogenic cooler. For the best performance, the resonant frequency of TDA needs to be essentially equal the driving frequency; accurate frequency match is favorably achieved by minimizing the cooler induced vibration by adjusting the driving frequency. For the best performance, the design of TDA needs to ensure minimum damping ratio; this is achievable by using planar flexural bearings having zero friction anchoring features. Accurate evaluation of effective mass, damping ratio and frequency is needed for TDA characterization during development and manufacturing. This data may be also important for the dynamic modelling. The authors are exploring the express method requiring no physical access to the proof mass of TDA. In this approach, the TDA is mounted upon the low frequency vibration mounted rod, the dynamic properties of TDA are then evaluated using the frequency response function - local accelerance - captured on the above rod using accelerometer, instrumented modal hammer and dual-channel signal analyzer. The authors are presenting the TDA design, outcomes of full-scale experimentation on dynamic properties evaluation and attained performance.

  8. Convective heat transfer in engine coolers influenced by electromagnetic fields

    Science.gov (United States)

    Karcher, C.; Kühndel, J.

    2017-08-01

    In engine coolers of off-highway vehicles, convective heat transfer at the coolant side limits both efficiency and performance density of the apparatus. Here, due to restrictions in construction and design, backwater areas and stagnation regions cannot be avoided. Those unwanted changes in flow characteristics are mainly triggered by flow deflections and sudden cross-sectional expansions. In application, mixtures of water and glysantine are used as appropriate coolants. Such coolants typically show an electrical conductivity of a few S/m. Coolant flow and convective heat transfer can then be controlled using Lorentz forces. These body forces are generated within the conducting fluid by the interactions of an electrical current density and a localized magnetic field, both of which are externally superimposed. In future application, this could be achieved by inserting electrodes in the cooler wall and a corresponding arrangement of permanent magnets. In this paper we perform numerical simulations of such magnetohydrodynamic flow in three model geometries that frequently appear in engine cooling applications: Carnot-Borda diffusor, 90° bend, and 180° bend. The simulations are carried out using the software package ANSYS Fluent. The present study demonstrates that, depending on the electromagnetic interaction parameter and the specific geometric arrangement of electrodes and magnetic field, Lorentz forces are suitable to break up eddy waters and separation zones and thus significantly increase convective heat transfer in these areas. Furthermore, the results show that hydraulic pressure losses can be reduced due to the pumping action of the Lorentz forces.

  9. Experimental research on thermoelectric cooler for imager camera thermal control

    Science.gov (United States)

    Hu, Bing-ting; Kang, Ao-feng; Fu, Xin; Jiang, Shi-chen; Dong, Yao-hai

    2013-09-01

    Conventional passive thermal design failed to satisfy CCD's temperature requirement on a geostationary earth orbit satellite Imager camera because of the high power and low working temperature, leading to utilization of thermoelectric cooler (TEC) for heat dissipation. TEC was used in conjunction with the external radiator in the CCDs' thermal design. In order to maintain the CCDs at low working temperature, experimental research on the performance of thermoelectric cooler was necessary and the results could be the guide for the application of TEC in different conditions. The experimental system to evaluate the performance of TEC was designed and built, consisting of TEC, heat pipe, TEC mounting plate, radiator and heater. A series of TEC performance tests were conducted for domestic and oversea TECs in thermal vacuum environment. The effects of TEC's mounting, input power and heat load on the temperature difference of TEC's cold and hot face were explored. Results demonstrated that the temperature difference of TEC's cold and hot face was slightly increased when TEC's operating voltage reached 80% of rating voltage, which caused the temperature rise of TEC's hot face. It recommended TEC to operate at low voltage. Based on experiment results, thermal analysis indicated that the temperature difference of TEC's cold and hot face could satisfy the temperature requirement and still had surplus.

  10. Refurbishment of the cryogenic coolers for the Skylab earth resources experiment package

    Science.gov (United States)

    Smithson, J. C.; Luksa, N. C.

    1975-01-01

    Skylab Earth Resources Experiment Package (EREP) experiments, S191 and S192, required a cold temperature reference for operation of a spectrometer. This cold temperature reference was provided by a subminiature Stirling cycle cooler. However, the failure of the cooler to pass the qualification test made it necessary for additional cooler development, refurbishment, and qualification. A description of the failures and the cause of these failures for each of the coolers is presented. The solutions to the various failure modes are discussed along with problems which arose during the refurbishment program. The rationale and results of various tests are presented. The successful completion of the cryogenic cooler refurbishment program resulted in four of these coolers being flown on Skylab. The system operation during the flight is presented.

  11. Reducing Display Bottle Cooler Energy Consumption Using PCM As Active Thermal Storage

    OpenAIRE

    Beek, Marcel van; de Jong, Hans

    2014-01-01

    The final results of an analytical and experimental study in reducing the energy consumption of a display bottle cooler using Phase Change Material (PCM) as an active thermal storage are presented. The objective of the study was to design and built a 350 dm3 glass door bottle cooler having an appliance energy consumption reduction of over 75% compared to state of the art bottle coolers (2010 figures). Calculation results show that active thermal storage using PCM can be effectively applied to...

  12. Functioning efficiency of intermediate coolers of multistage steam-jet ejectors of steam turbines

    Science.gov (United States)

    Aronson, K. E.; Ryabchikov, A. Yu.; Brodov, Yu. M.; Zhelonkin, N. V.; Murmanskii, I. B.

    2017-03-01

    Designs of various types of intermediate coolers of multistage ejectors are analyzed and thermal effectiveness and gas-dynamic resistance of coolers are estimated. Data on quantity of steam condensed from steam-air mixture in stage I of an ejector cooler was obtained on the basis of experimental results. It is established that the amount of steam condensed in the cooler constitutes 0.6-0.7 and is almost independent of operating steam pressure (and, consequently, of steam flow) and air amount in steam-air mixture. It is suggested to estimate the amount of condensed steam in a cooler of stage I based on comparison of computed and experimental characteristics of stage II. Computation taking this hypothesis for main types of mass produced multistage ejectors into account shows that 0.60-0.85 of steam amount should be condensed in stage I of the cooler. For ejectors with "pipe-in-pipe" type coolers (EPO-3-200) and helical coolers (EO-30), amount of condensed steam may reach 0.93-0.98. Estimation of gas-dynamic resistance of coolers shows that resistance from steam side in coolers with built-in and remote pipe bundle constitutes 100-300 Pa. Gas-dynamic resistance of "pipein- pipe" and helical type coolers is significantly higher (3-6 times) compared with pipe bundle. However, performance by "dry" (atmospheric) air is higher for ejectors with relatively high gas-dynamic resistance of coolers than those with low resistance at approximately equal operating flow values of ejectors.

  13. Direct Evaporatrive Coolers of Gases and Liquids with Lowered Limit of Cooling

    Directory of Open Access Journals (Sweden)

    Doroshenko A.V.

    2015-12-01

    Full Text Available We have developed main technical solutions solution of indirect evaporative water and air coolers with reduced cooling limit. Packed part of heat-mass transfer devices is made of the film type based monoblock compositions of polymer materials. A mathematical model describing the processes of joint heat and mass transfer in evaporative coolers is executed. A comparative analysis of the possibilities of coolers designed based on experimental data on the efficiency of processes of heat and mass transfer.

  14. Calculation Method for the Prediction of the Performance of a Traveling-Wave Thermoacoustic Cooler

    Science.gov (United States)

    Ueda, Yuki

    When a traveling acoustic wave propagates through a regenerator, the gas in the regenerator undergoes the Stirling thermodynamic cycle, and thus, the energy conversion between heat flux and acoustic power takes place. A cooler that utilizes this energy conversion is called as a traveling-wave thermoacoustic cooler. Swift et al. [The Journal of the Acoustical Society of America, 105, 711 (1998)] have proposed a new traveling wave thermoacoustic cooler that is equipped with a looped tube. This paper describes a numerical method to estimate the performance of this thermoacoustic cooler and shows a comparison between the estimated and experimentally obtained performances.

  15. A computer program for designing fin-and-tube heat exchanger for EGR cooler application

    Science.gov (United States)

    Syaiful, Marwan, M. A.; Tandian, N. P.; Bae, M.

    2016-03-01

    EGR (exhaust gas recirculation) cooler is a kind of heat exchanger that is used to cool exhaust gas recirculation prior to be mixed with fresh air in an intake manifold of vehicle in order to obtain good reduction of NOxemissions. A fin-and-tube heat exchanger is more preferred as an EGR cooler than a shell-and-tube heat exchanger in this study due to its compactness. Manually designing many configurations of fin-and-tube heat exchanger for EGR cooler application consumes a lot of time and is high cost. Therefore, a computer aided design process of EGR cooler is required to overcome this problem. The EGR cooler design process was started by arranging the sequences of calculation algorithm in a computer program. A cooling media for this EGR cooler is air. The design is based on the effectiveness-number transfer unit (NTU) method. The EGR cooler design gives the geometry, heat transfer surface area, heat transfer coefficient and pressure drop of the EGR cooler. Comparison of the EGR cooler Nusselt number obtained in this study and that reported in literature shows less than 6.2% discrepancy.

  16. High Coefficient of Performance HgCdTe And Metallic Superlattice-Based Thermoelectric Coolers Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose the development of nanoscale superlattices (SLs) as the active elements of high efficiency thermoelectric coolers. Recent models predict that the...

  17. Structural value of Yerevan streets

    Directory of Open Access Journals (Sweden)

    Avetisyan Arsen Grantovich

    2015-04-01

    Full Text Available The absence of the methods of urban analysis in the process of urban development of Yerevan is the reason of urban planning activities that tend to decrease the urban value of Yerevan territories. Meanwhile the studies in the sphere of urban planning and urban analysis prove the dependence of the life in the city on its structure and distribution of the functions. The mentioned issue highlights the importance of urban analysis. The paper discusses space syntax, which is one of the initial methods of urban analysis. The basic concept of Space syntax is based on the assumption that urban fabric can be presented and studied as a power graph. The method provides the measures that evaluate the land use, traffic and pedestrian movement, land value and even carbon emissions. The paper discusses also recent attempts of integration of space syntax method into GIS environment. GIS databases provide researchers with vast amount of urban data. Analyses presented in the current paper were performed on the basis of the open street map, which was imported from the GIS environment. With the application of space syntax methods analysis of connectivity, integration choice (betweenness and depth from the city center were performed to evaluate the structural value of Yerevan streets. Municipal regions of Yerevan were classified by the level of their accessibility and by their distances from the city center on the base of the results of depth measures from the city center. Evaluation of the street network aims to define the most integrated and centrally positioned parts of the city. These areas can be locations for the organization of sub centers of Yerevan in the municipal regions.

  18. Temperature Control of Avalanche Photodiode Using Thermoelectric Cooler

    Science.gov (United States)

    Refaat, Tamer F.; Luck, William S., Jr.; DeYoung, Russell J.

    1999-01-01

    Avalanche photodiodes (APDS) are quantum optical detectors that are used for visible and near infrared optical detection applications. Although APDs are compact, rugged, and have an internal gain mechanism that is suitable for low light intensity; their responsivity, and therefore their output, is strongly dependent on the device temperature. Thermoelectric coolers (TEC) offers a suitable solution to this problem. A TEC is a solid state cooling device, which can be controlled by changing its current. TECs are compact and rugged, and they can precisely control the temperature to within 0.1 C with more than a 150 C temperature gradient between its surfaces. In this Memorandum, a proportional integral (PI) temperature controller for APDs using a TEC is discussed. The controller is compact and can successfully cool the APD to almost 0 C in an ambient temperature environment of up to 27 C.

  19. Performances of thermoelectric cooler integrated with microchannel heat sinks

    Energy Technology Data Exchange (ETDEWEB)

    Reiyu Chein; Yehong Chen [National Chung Hsing University, Taichung (Taiwan). Department of Mechanical Engineering

    2005-09-01

    In this study, experimental and theoretical studies on thermoelectric cooler (TEC) performance for cooling a refrigerated object (water in a tank) were performed. Microchannel heat sinks fabricated with etched silicon wafers were employed on the TEC hot side to dissipate heat. The measurements show that the temperature of the refrigerated object decreased with time. A theoretical model based on a lumped system was established to predict the transient behavior of the variation in temperature for the refrigerated object with time. The theoretical predicted temperature variation was in good agreement with the measured data. The relationship among the heat sink thermal resistances, TEC electric current input and minimum refrigerated objected temperature was examined based on the theoretical model. The calculated minimum temperatures were showed for the several cases of heat sink thermal resistance on the TEC hot side and electric current input. The minimum temperature can be obtained by increasing the electrical current input and decreasing the heat sink thermal resistance. (author)

  20. Modeling of efficient solid-state cooler on layered multiferroics.

    Science.gov (United States)

    Starkov, Ivan; Starkov, Alexander

    2014-08-01

    We have developed theoretical foundations for the design and optimization of a solid-state cooler working through caloric and multicaloric effects. This approach is based on the careful consideration of the thermodynamics of a layered multiferroic system. The main section of the paper is devoted to the derivation and solution of the heat conduction equation for multiferroic materials. On the basis of the obtained results, we have performed the evaluation of the temperature distribution in the refrigerator under periodic external fields. A few practical examples are considered to illustrate the model. It is demonstrated that a 40-mm structure made of 20 ferroic layers is able to create a temperature difference of 25K. The presented work tries to address the whole hierarchy of physical phenomena to capture all of the essential aspects of solid-state cooling.

  1. Integration of RFQ beam coolers and solenoidal magnetic fields

    Science.gov (United States)

    Cavenago, M.; Romé, M.; Maggiore, M.; Porcellato, A. M.; Maero, G.; Chiurlotto, F.; Comunian, M.; Galatà, A.; Cavaliere, F.

    2016-02-01

    Electromagnetic traps are a flexible and powerful method of controlling particle beams, possibly of exotic nuclei, with cooling (of energy spread and transverse oscillations) provided by collisions with light gases as in the Radio Frequency Quadrupole Cooler (RFQC). A RFQC prototype can be placed inside the existing Eltrap solenoid, capable of providing a magnetic flux density component Bz up to 0.2 T, where z is the solenoid axis. Confinement in the transverse plane is provided both by Bz and the rf voltage Vrf (up to 1 kV at few MHz). Transport is provided by a static electric field Ez (order of 100 V/m), while gas collisions (say He at 1 Pa, to be maintained by differential pumping) provide cooling or heating depending on Vrf. The beamline design and the major parameters Vrf, Bz (which affect the beam transmission optimization) are here reported, with a brief description of the experimental setup.

  2. Optimization of a microfluidic electrophoretic immunoassay using a Peltier cooler.

    Science.gov (United States)

    Mukhitov, Nikita; Yi, Lian; Schrell, Adrian M; Roper, Michael G

    2014-11-07

    Successful analysis of electrophoretic affinity assays depends strongly on the preservation of the affinity complex during separations. Elevated separation temperatures due to Joule heating promotes complex dissociation leading to a reduction in sensitivity. Affinity assays performed in glass microfluidic devices may be especially prone to this problem due to poor heat dissipation due to the low thermal conductivity of glass and the large amount of bulk material surrounding separation channels. To address this limitation, a method to cool a glass microfluidic chip for performing an affinity assay for insulin was achieved by a Peltier cooler localized over the separation channel. The Peltier cooler allowed for rapid stabilization of temperatures, with 21°C the lowest temperature that was possible to use without producing detrimental thermal gradients throughout the device. The introduction of cooling improved the preservation of the affinity complex, with even passive cooling of the separation channel improving the amount of complex observed by 2-fold. Additionally, the capability to thermostabilize the separation channel allowed for utilization of higher separation voltages than what was possible without temperature control. Kinetic CE analysis was utilized as a diagnostic of the affinity assay and indicated that optimal conditions were at the highest separation voltage, 6 kV, and the lowest separation temperature, 21°C, leading to 3.4% dissociation of the complex peak during the separation. These optimum conditions were used to generate a calibration curve and produced 1 nM limits of detection, representing a 10-fold improvement over non-thermostated conditions. This methodology of cooling glass microfluidic devices for performing robust and high sensitivity affinity assays on microfluidic systems should be amenable in a number of applications.

  3. Agglomeration in Stripper Ash Coolers and Its Possible Remedial Solutions: a Case Study

    Science.gov (United States)

    Singh, Ravi Inder

    2016-04-01

    The bottom ash of circulating fluidized bed (CFB) boiler contains large amounts of physical heat. When low quality coals are used in these types of boilers, the ash content is normally more than 40 % and the physical heat loss is approximately 3 % if the bottom ash is discharged without cooling. Bottom ash cooler (BAC) is often used to treat the high temperature bottom ash to reclaim heat, and to facilitate the easily handling and transportation of ash. The CFB boiler at BLA Power, Newari, MP (India) is facing problems of clinker formation in strip ash coolers of plant since the installation of unit. These clinkers are basically agglomerates, which leads to defluidization of stripper ash cooler (BAC) units. There are two strip ash coolers in unit. Each strip ash cooler is capable of working independently. The proper functioning of both strip coolers is very important as it is going to increase the combustion efficiency of boiler by stripping of fine unburnt coal particles from ash, which are injected into the furnace. In this paper causes, characterization of agglomerates, thermo gravimetric analysis of fuel used, particular size distribution of coal and sand and possible remedial solution to overcome these agglomerates in strip ash coolers has also been presented. High temperature in compact separators, non uniform supply of coal and not removing small agglomerates from stripper ash cooler are among main causes of agglomeration in stripper ash cooler. Control of compact separator temperature, replacing 10-12 % of bed material and cleaning stripper ash cooler periodically will decrease agglomeration in stripper ash cooler of unit.

  4. Microbiological quality of selected street food items vended by school-based street food vendors in Dhaka, Bangladesh.

    Science.gov (United States)

    Al Mamun, Mohammad; Rahman, Shah Mahfuzur; Turin, Tanvir Chowdhury

    2013-09-16

    A cross sectional study was conducted to assess the microbiological quality of local food items vended by the school-based street food vendors in Dhaka City. A total of 80 schools from 19 school-zones of Dhaka City and its outskirts were chosen for the study. A total of 110 food samples, one each from 110 school-based street food vendors, were collected for laboratory analysis. Face to face interviews were conducted with the food vendors using a pre-tested questionnaire. The food samples were analyzed for coliform counts in the Public Health Laboratory, Institute of Public Health, Dhaka, which is a national level central food testing laboratory in Bangladesh. Microbiological criteria recommended by the International Commission on Microbiological Specifications for Foods (ICMSF) were considered to classify food samples as 'satisfactory' (total coliforms food vendors with the presence of unsatisfactory levels of coliforms in their food items. Of the 110 school-based street food samples analyzed in the laboratory, 44% were unsatisfactory. Among different items of street vended foods, 54% of sliced fruits samples, 59% of jhalmuri samples, 29% of chotpotis samples, 53% of vajavuji samples, and all (100%) sharbat samples were unsatisfactory, while all samples from achar (100%) and ice cream (100%) were found to be satisfactory. Logistic regression models showed that the food samples collected from the vendors belonging to the age group '15-24 years' and the vendors possessing an educational status higher than primary level were less likely to be unsatisfactory, while the food samples collected from the vendors having a daily income of more than 200 Bangladeshi Taka (equivalent to 3.00 USD) were more likely to be unsatisfactory. Our study findings reflected poor microbiological quality for a considerable proportion of the school-based street vended foods indicating a health threat to the school children of Dhaka City.

  5. Georges Charpak street sign unveiled

    CERN Multimedia

    Paola Catapano

    2011-01-01

    While it might not be the only French street named in honour of the late Georges Charpak, who passed away in September 2010 at the age of 87, the street chosen by the mayor of Saint-Genis-Pouilly is certainly the only one located directly opposite the CERN "campus". The road overlooks buildings on the CERN Meyrin site, where Georges Charpak spent most of his career as a physicist, conducting the research that won him the Nobel Prize in Physics in 1992.   From left to right: Sigurd Lettow, Dominique Charpak and the mayor of Saint-Genis-Pouilly. The unveiling took place on 17 October and was organised by the mayor of Saint-Genis-Pouilly. George Charpak’s wife, Dominique, and Sigurd Lettow, CERN Director of Administration and General Infrastructure, attended what was an intimate and touching ceremony. The mayor’s speech at the event praised Georges’ commitment to scientific education. The highlight of the event, however, was a witty and humorous ...

  6. School Me, School Me Not, Street Me, Street Me Not…

    DEFF Research Database (Denmark)

    Gravesen, David Thore; Frostholm, Peter Hornbæk

    2016-01-01

    of 2014, we conducted an ethnographic fieldwork (Atkinson & Hammersley 2007; Hastrup 2010; Spradley 1980) among urban youth in a mid-sized Danish provincial town. Different groupings of youth attended the skater and parkour facilities at the central squares, all of them with each their strategies....... Obviously, the skaters attend the site to skate. But also other, more vulnerable groupings, use the site to socialize, meet peers and perhaps escape an unreliable and risky family arena. One particular group, the self-named Thugz, primarily formed around a number of young boys with non-Danish ethnic...... the vulnerable urban youth cope with the obvious challenges related to the dissimilar imperatives of the street, the family and the school?...

  7. Assessing canopy cover over streets and sidewalks in street tree populations

    Science.gov (United States)

    S.E. Maco; E.G. McPherson

    2002-01-01

    Total canopy cover and canopy cover over street and sidewalk surfaces were estimated for street trees in Davis, California, U.S. Calculations were made using simple trigonometric equations based on the results of a sample inventory. Canopy cover from public trees over streets and sidewalks varied between 4% and 46% by city zone, averaging 14% citywide. Consideration of...

  8. Relationships between the Sociodemographic and Family Characteristics, Street Life Experiences and the Hopelessness of Street Children

    Science.gov (United States)

    Duyan, Veli

    2005-01-01

    Throughout its history, street children have been a major concern of Turkish society and have lately been uppermost on social workers agenda. This study examines the relationships between sociodemographic and family characteristics, family relations, street life experiences and the hopelessness of street children. The study focuses on a population…

  9. Adolescent Hopefulness in Tanzania: Street Youth, Former Street Youth, and School Youth

    Science.gov (United States)

    Nalkur, Priya G.

    2009-01-01

    This study compares hope in street youth, former street youth, and school youth (aged 12-18) in Tanzania. Responding to Snyder's hope theory, the author argues that not only personal agency but also the stability of living context (street, shelter, home) shapes hopefulness. Employing qualitative and quantitative analyses, the author presents a…

  10. Flexible Digital Control & Driving Electronics For Cryo-Coolers Application To Sentinel-3 SLSTR

    Science.gov (United States)

    Chico, J. C.; Caballero, G.; Gonzalez, D.; Fernandez, A.; Romero, V.; Bataller, E.

    2011-10-01

    The digital control as well as the power electronic implemented in the "Cryo-Cooler Driver Electronics" CDE units have evolved along these last years to new concepts allowing an easier management of the Cryo- coolers in flight programs, at the same time that the performances have been improved. A good example of this evolution in the CDE equipments is the one developed by Astrium Crisa for the Stirling Cooler of Astrium UK of the Sea & Land Surface Temperature Radiometer (SLSTR) instrument, which will be boarded in Sentinel-3. A new concept of CDE has been developed not only to satisfy the specific requirements of the SLSTR Stirling Cooler, but also to get a very modular and scalable architecture that can be adapted easily to different configurations of coolers. This paper describes the SLSTR CDE architecture, showing the problems found during the development of the unit as well as the latest performances achieved during the testing of the EM.

  11. RACE, CODE OF THE STREET, AND VIOLENT DELINQUENCY: A MULTILEVEL INVESTIGATION OF NEIGHBORHOOD STREET CULTURE AND INDIVIDUAL NORMS OF VIOLENCE.

    Science.gov (United States)

    Stewart, Eric A; Simons, Ronald L

    2010-05-01

    The study outlined in this article drew on Elijah Anderson's (1999) code of the street perspective to examine the impact of neighborhood street culture on violent delinquency. Using data from more than 700 African American adolescents, we examined 1) whether neighborhood street culture predicts adolescent violence above and beyond an adolescent's own street code values and 2) whether neighborhood street culture moderates individual-level street code values on adolescent violence. Consistent with Anderson's hypotheses, neighborhood street culture significantly predicts violent delinquency independent of individual-level street code effects. Additionally, neighborhood street culture moderates individual-level street code values on violence in neighborhoods where the street culture is widespread. In particular, the effect of street code values on violence is enhanced in neighborhoods where the street culture is endorsed widely.

  12. The Street Children Development in Open House

    Directory of Open Access Journals (Sweden)

    Didin Saripudin

    2012-01-01

    Full Text Available Problem statement: The street children handling through open house has been developed in Indonesia since 1998. One of street children handling steps in open house is resocialization. This study is conducted to evaluate the effect of resocialization program implemention in open house on the street children and to determine how far such program reached its goal. Approach: The design of this study was program evaluation using quantitative approach. This study used Context, Input, Process and Product (CIPP evaluation model by focusing on three of four components of CIPP evaluation model such as input, process and product. The population and sample of the study were administrator, facilitator and street children chosen from 16 open houses in Bandung City, West Java Province, Indonesia. Results: The perception of administrator, facilitator and street children on input relevance was positive in avarage level. The perception of administrator, facilitator and street children on process was positive in avarage and high level. This study also presents input and process variables contribute significantly toward the product variable. Conclusion/Recommendations: The street children resocialization program in open house in Bandung, from input, process and product components, is generally in average level, there are still some weaknesses that can be handled. In order to reach the goal of street children resocialization in open house, corrective action can be taken comprehensively and synergically by the responsible ones.

  13. Psychological Characteristics of South African Street Children.

    Science.gov (United States)

    le Roux, Johann; Smith, Cheryl Sylvia

    1998-01-01

    Attempts to identify the psychological characteristics that predispose certain children to run away and to survive, often for long periods, on the streets of South Africa. Examines vulnerability and resilience as well as social conditions that mediate the psychological predisposition to become a street child. (Author/GCP)

  14. MAPCERN links to Google Street View

    CERN Multimedia

    Matilda Heron

    2015-01-01

    CERN’s online maps, MAPCERN, now have the added bonus of Google Street View, thanks to the new release of images of many CERN sites captured by Google.   New Street View images of CERN sites have been added to MAPCERN, see bottom-right-hand image in the screenshot above.   Google Street View, an integrated service of Google Maps introduced in 2007, links 360-degree panoramic photos into a virtual tour. CERN and Google began collaborating on this Street View project in 2010 and now these Street View images have been embedded into MAPCERN, accessible by clicking the “Street View” tab in MAPCERN’s bottom-right-hand window. If you need to locate a building at CERN, or plan an operation on some equipment, you can save time by using the Street View images to check out the area in advance. The CERN Meyrin site has been fully mapped, as well as the surfaces of the eight LHC points, BA2 and BA3. New Street View images of CERN, including the Pr...

  15. Trauma among Street-Involved Youth

    Science.gov (United States)

    Bender, Kimberly A.; Thompson, Sanna J.; Ferguson, Kristin M.; Yoder, Jamie R.; Kern, Leah

    2014-01-01

    Previous research documents that street-involved youth experience rates of trauma and posttraumatic stress disorder (PTSD) that are significantly higher than their housed counterparts. Trauma and PTSD are of particular concern for homeless youth as they can negatively affect youths' ability to function adaptively and to transition off the streets.…

  16. Street Photography from the Subject's Viewpoint.

    Science.gov (United States)

    Nottingham, Emily

    To investigate the reaction of the public to being photographed on the street, a study was devised whereby seven photojournalists approached people on the street, photographed them, and requested identification for a questionnaire follow up. Of 102 people approached, 87% cooperated fully with the photographers and 81% of that group returned the…

  17. Trauma among Street-Involved Youth

    Science.gov (United States)

    Bender, Kimberly A.; Thompson, Sanna J.; Ferguson, Kristin M.; Yoder, Jamie R.; Kern, Leah

    2014-01-01

    Previous research documents that street-involved youth experience rates of trauma and posttraumatic stress disorder (PTSD) that are significantly higher than their housed counterparts. Trauma and PTSD are of particular concern for homeless youth as they can negatively affect youths' ability to function adaptively and to transition off the streets.…

  18. PLC based Smart Street Lighting Control

    Directory of Open Access Journals (Sweden)

    D.V.Pushpa Latha

    2013-12-01

    Full Text Available Conventional street lighting systems in most of the areas are Online at regular intervals of time irrespective of the seasonal variations. The street lights are simply switched on at afternoon and turned off in the morning. The consequence is that a large amount of Power is wasted meaninglessly. As energy consumption is an issue of increasing interest, possible energy savings in public street lighting systems are recently discussed from different viewpoints. The purpose of this work is to describe the Smart Street Lighting system, an approach to accomplish the demand for flexible public lighting systems using a Programmable Logic controller (PLC. The main difference from other computers is that PLCs are armoured for severe conditions such as dust, moisture, heat, cold etc., and have the facility for extensive input/output (I/O arrangements. In the proposed paper, street lights are controlled using millennium 3 PLC taking the seasonal variations into consideration.

  19. Thermal electron-tunneling devices as coolers and amplifiers

    Science.gov (United States)

    Su, Shanhe; Zhang, Yanchao; Chen, Jincan; Shih, Tien-Mo

    2016-02-01

    Nanoscale thermal systems that are associated with a pair of electron reservoirs have been previously studied. In particular, devices that adjust electron tunnels relatively to reservoirs’ chemical potentials enjoy the novelty and the potential. Since only two reservoirs and one tunnel exist, however, designers need external aids to complete a cycle, rendering their models non-spontaneous. Here we design thermal conversion devices that are operated among three electron reservoirs connected by energy-filtering tunnels and also referred to as thermal electron-tunneling devices. They are driven by one of electron reservoirs rather than the external power input, and are equivalent to those coupling systems consisting of forward and reverse Carnot cycles with energy selective electron functions. These previously-unreported electronic devices can be used as coolers and thermal amplifiers and may be called as thermal transistors. The electron and energy fluxes of devices are capable of being manipulated in the same or oppsite directions at our disposal. The proposed model can open a new field in the application of nano-devices.

  20. Study of Voltage-Controlled Characteristics for Thermoelectric Coolers

    Science.gov (United States)

    Wang, Ning; Chen, Ming-Ming; Jia, Hong-Zhi; Jin, Tao; Xie, Ji-Long

    2017-01-01

    Based on the Peltier effect, thermoelectric coolers (TECs) have been widely used in solving thermal management issues for semiconductor devices such as semiconductor laser, charge-coupled devices and nanoelectronic circuits with hot-spots. However, performance control mechanisms especially voltage-controlled parameters for TEC still face challenges. In this paper, a standard mathematical model for multi-stage TECs is proposed with thermal resistances from both sides and performance parameters dependent on voltage. The proposed models agreed with experimental results. Compared with the available model, the relative standard deviations between the obtained equivalent thermal conductivity model and experimental results at 25°C and 50°C are decreased by 88.87% and 30.14%, respectively. Also, the relative standard deviations between the proposed thermoelectric figure of merits model and calculated results based on experiments at two different temperatures are decreased by 84.45% and 62.94%, respectively. The results provide a controllable method of thermoelectric characteristics with high accuracy, which can be employed for early thermometric performance estimation for TEC design.

  1. Life and Reliability Characteristics of TurboBrayton Coolers

    Science.gov (United States)

    Breedlove, Jeff J.; Zagarola, Mark; Nellis, Greg; Dolan, Frank; Swift, Walt; Gibbon, Judith; Obenschain, Arthur F. (Technical Monitor)

    2000-01-01

    Wear and internal contaminants are two of the primary factors that influence reliable, long-life operation of turbo-Brayton cryocoolers. This paper describes tests that have been conducted and methods that have been developed for turbo-Brayton components and systems to assure reliable operation. The turbomachines used in these coolers employ self-acting gas bearings to support the miniature high-speed shafts, thus providing vibration-free operation. Because the bearings are self-acting, rubbing contact occurs during initial start-up and shutdown of the machines. Bearings and shafts are designed to endure multiple stop/start cycles without producing particles or surface features that would impair the proper operation of the machines. Test results are presented for a variety of turbomachines used in these systems. The tests document extended operating life and start/stop cycling behavior for machines over a range of time and temperature scales. Contaminants such as moisture and other residual gas impurities can be a source of degraded operation if they freeze out in sufficient quantities to block flow passages or if they mechanically affect the operation of the machines. A post-fabrication bakeout procedure has been successfully used to reduce residual internal contamination to acceptable levels in a closed cycle system. The process was developed during space qualification tests on the NICMOS cryocooler. Moisture levels were sampled over a six-month time interval confirming the effectiveness of the technique. A description of the bakeout procedure is presented.

  2. Boiling process in oil coolers on porous elements

    Directory of Open Access Journals (Sweden)

    Genbach Alexander A.

    2016-01-01

    Full Text Available Holography and high-speed filming were used to reveal movements and deformations of the capillary and porous material, allowing to calculate thermo-hydraulic characteristics of boiling liquid in the porous structures. These porous structures work at the joint action of capillary and mass forces, which are generalised in the form of dependences used in the calculation for oil coolers in thermal power plants (TPP. Furthermore, the mechanism of the boiling process in porous structures in the field of mass forces is explained. The development process of water steam formation in the mesh porous structures working at joint action of gravitational and capillary forces is investigated. Certain regularities pertained to the internal characteristics of boiling in cells of porous structure are revealed, by means of a holographic interferometry and high-speed filming. Formulas for calculation of specific thermal streams through thermo-hydraulic characteristics of water steam formation in mesh structures are obtained, in relation to heat engineering of thermal power plants. This is the first calculation of heat flow through the thermal-hydraulic characteristics of the boiling process in a reticulated porous structure obtained by a photo film and holographic observations.

  3. Cryogenic characterization of the Planck sorption cooler system flight model

    CERN Document Server

    Morgante, G; Melot, F; Stassi, P; Terenzi, L; Wilson, P; Hernandez, B; Wade, L; Gregorio, A; Bersanelli, M; Butler, C; Mandolesi, N; 10.1088/1748-0221/4/12/T12016

    2009-01-01

    This paper is part of the Prelaunch status LFI papers published on JINST: http://www.iop.org/EJ/journal/-page=extra.proc5/1748-0221 Two continuous closed-cycle hydrogen Joule-Thomson (J-T) sorption coolers have been fabricated and assembled by the Jet Propulsion Laboratory (JPL) for the European Space Agency (ESA) Planck mission. Each refrigerator has been designed to provide a total of ~ 1W of cooling power at two instrument interfaces: they directly cool the Planck Low Frequency Instrument (LFI) around 20K while providing a pre-cooling stage for a 4 K J-T mechanical refrigerator for the High Frequency Instrument (HFI). After sub-system level validation at JPL, the cryocoolers have been delivered to ESA in 2005. In this paper we present the results of the cryogenic qualification and test campaigns of the Nominal Unit on the flight model spacecraft performed at the CSL (Centre Spatial de Liege) facilities in 2008. Test results in terms of input power, cooling power, temperature, and temperature fluctuations o...

  4. Cooler Storage Ring at China Institute of Modern Physics

    CERN Document Server

    Wen-Xia, Jia; Zhan, W

    2005-01-01

    CSR, a new ion cooler-storage-ring project in China IMP, is a double ring system, and consists of a main ring (CSRm) and an experimental ring (CSRe). The two existing cyclotrons SFC (K=69) and SSC (K=450) of the Heavy Ion Research Facility in Lanzhou (HIRFL) will be used as its injector system. The heavy ion beams with the energy range of 7-30 MeV/nucleus from the HIRFL will be accumulated, cooled and accelerated to the higher energy range of 100-500 MeV/ nucleus in CSRm, and then extracted fast to produce radioactive ion beams or highly charged heavy ions. Those secondary beams will be accepted and stored or decelerated by CSRe for many internal-target experiments or high precision spectroscopy with beam cooling. On the other hand, the beams with the energy range of 100-1000MeV/ nucleus will also be extracted from CSRm by using slow extraction or fast extraction for many external-target experiments. CSR project was started in the end of 1999 and will be finished in 2006. In this paper the outline and the act...

  5. Cryogenic characterization of the Planck sorption cooler system flight model

    Energy Technology Data Exchange (ETDEWEB)

    Morgante, G; Terenzi, L; Butler, C; Mandolesi, N [INAF - IASF Bologna, via P. Gobetti 101, 40129 Bologna (Italy); Pearson, D; Wilson, P; Hernandez, B; Wade, L [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena California 91109 (United States); Melot, F; Stassi, P [Laboratoire de Physique Subatomique et de Cosmologie 53 Avenue des Martyrs, 38026 Grenoble Cedex (France); Gregorio, A [Dipartimento di Fisica, Universita degli Studi di Trieste, via Valerio 2 - I-34127 Trieste (Italy); Bersanelli, M, E-mail: morgante@iasfbo.inaf.i [Dipartimento di Fisica, Universita degli Studi di Milano, via Celoria 16, - I20133 Milano (Italy)

    2009-12-15

    Two continuous closed-cycle hydrogen Joule-Thomson (J-T) sorption coolers have been fabricated and assembled by the Jet Propulsion Laboratory (JPL) for the European Space Agency (ESA) Planck mission. Each refrigerator has been designed to provide a total of {approx} 1W of cooling power at two instrument interfaces: they directly cool the Planck Low Frequency Instrument (LFI) around 20K while providing a pre-cooling stage for a 4 K J-T mechanical refrigerator for the High Frequency Instrument (HFI). After sub-system level validation at JPL, the cryocoolers have been delivered to ESA in 2005. In this paper we present the results of the cryogenic qualification and test campaigns of the Nominal Unit on the flight model spacecraft performed at the CSL (Centre Spatial de Liege) facilities in 2008. Test results in terms of input power, cooling power, temperature, and temperature fluctuations over the flight allowable ranges for these interfaces are reported and analyzed with respect to mission requirements.

  6. A novel coupling configuration for thermoacoustically-driven pulse tube coolers: Acoustic amplifier

    Institute of Scientific and Technical Information of China (English)

    DAI Wei; LUO Ercang; HU Jianying; CHEN Yanyan

    2005-01-01

    Thermoacoustically-driven pulse tube cooler can provide cryogenic cooling power with no moving components. Up to now, pulse tube cooler is directly coupled with the thermoacoustic engine and obtainable pressure ratio for the pulse tube cooler is limited by the capability of the thermoacoustic engine. The authors propose here the concept of acoustic amplifier, which is actually a long tube connecting the engine with the pulse tube cooler. Theoretical calculation shows that suitable length and diameter of the tube can lead to a pressure wave amplification effect which means that pressure wave amplitude coming from the thermoacoustic engine can be much amplified to drive the pulse tube cooler. Based on this, a 2.8 m long copper tube with 8 mm inner diameter is used as the acoustic amplifier in experiments. The experimental results show that due to the amplification effect, pressure wave amplitude at the inlet of the pulse tube cooler is over 2.5 times of that at the engine outlet. Typically, with 1.67 kW heating power, the pressure ratio provided by the engine is 1.11 while at the inlet of the pulse tube cooler the pressure ratio is 1.32, which leads to a lowest no-load temperature of 65.7 K.

  7. Evaluation of the Influence of Conventional Water Coolers on Drinking Water Quality

    Directory of Open Access Journals (Sweden)

    M Nikaeen

    2010-02-01

    Full Text Available "n "nBackgrounds and Objectives: Drinking water quality after treatment and before reaching  the consumer could be affected by distribution pipes, service lines and Home devices. The structure of water coolers, a home device that are widely used in warm months of the year, could potentially affect the quality of drinking water. The aim of this study was to assess the microbial and chemical quality of water from conventional water coolers."nMaterials and Methods : Water samples were collected from 29 water cooler systems at the Isfahan  university of medical sciences. 29 control samples also obtained from the nearest drinking water taps. All samples were examined for total heterotrophic bacteria and physicochemical parameters including temperature, ph, turbidity and heavy metals."nResults: All samples from the water cooler systems complied with the EPA guidelines for total heterotrophic bacteria count. There were no significant differences between the levels of heavy metals in water samples from the water cooler systems and taps. There was only a significant difference between the level of Cu in the water samples from cooler systems and taps "nConclusion: The overall results of this study indicated that the use of water cooler systems from hygienic point of view could not cause any problems for consumers

  8. 40 CFR 63.2267 - Initial compliance demonstration for a reconstituted wood product press or board cooler.

    Science.gov (United States)

    2010-07-01

    ... reconstituted wood product press or board cooler. 63.2267 Section 63.2267 Protection of Environment... for a reconstituted wood product press or board cooler. If you operate a reconstituted wood product press at a new or existing affected source or a reconstituted wood product board cooler at a...

  9. Fabrication of integrated planar gunn diode and\\ud micro-cooler on GaAs substrate

    OpenAIRE

    Khalid, Ata-ul-Habib; Glover, J.; Hopper, R; Papageorgiou, V.; M. Montes; Kuball, M.; Dunn, G.; Stephen, A.; Oxley, C.; D. R. S. Cumming

    2013-01-01

    We demonstrate fabrication of an integrated\\ud micro cooler with the planar Gunn diode and characterise\\ud its performance. First experimental results have shown a\\ud small cooling at the surface of the micro cooler. This is first\\ud demonstration of an integrated micro-cooler with a planar\\ud Gunn diode.

  10. RACE, CODE OF THE STREET, AND VIOLENT DELINQUENCY: A MULTILEVEL INVESTIGATION OF NEIGHBORHOOD STREET CULTURE AND INDIVIDUAL NORMS OF VIOLENCE*

    OpenAIRE

    Stewart, Eric A.; Simons, Ronald L.

    2010-01-01

    The study outlined in this article drew on Elijah Anderson’s (1999) code of the street perspective to examine the impact of neighborhood street culture on violent delinquency. Using data from more than 700 African American adolescents, we examined 1) whether neighborhood street culture predicts adolescent violence above and beyond an adolescent’s own street code values and 2) whether neighborhood street culture moderates individual-level street code values on adolescent violence. Consistent w...

  11. High-T{sub c} DC SQUID system cooled by pulse-tube cooler

    Energy Technology Data Exchange (ETDEWEB)

    He, D.F.; Nakamura, M.; Yoshizawa, M

    2003-10-15

    We developed a high-T{sub c} DC SQUID system cooled by pulse-tube cooler. To avoid the influence of the wire resistance between SQUID and preamplifier, and to reduce the influence of the temperature fluctuation of pulse-tube cooler, DC coupling between SQUID chip and preamplifier was used and the flux locked loop worked in modulation mode. We also developed a temperature controller, using the DC SQUID as temperature sensor, to control and stabilize the operating temperature of the pulse-tube cooler. With the temperature controller, the DC SQUID system could remain locked for over 8 h.

  12. Verification of Methodology for Determination of Deposit Thickness on Heat Transfer Surface of Natural Gas Coolers

    Directory of Open Access Journals (Sweden)

    Miroslav PŘÍHODA

    2010-12-01

    Full Text Available The paper describes briefly an original methodology for the determination of the deposit thickness on the inside heat transfer surface of natural gas cooler and a procedure of its verification at the cooler CH_R of the booster station KS01 in Velké Kapušany. The methodology is based on the measurement of the degree of the gas cooling. It has the universal validity and can be used to determine the thickness of the deposits of all types of coolers working on any booster station.

  13. Low-energy run of Fermilab Electron Cooler's beam generation system

    Energy Technology Data Exchange (ETDEWEB)

    Prost, Lionel; Shemyakin, Alexander; /Fermilab; Fedotov, Alexei; Kewisch, Jorg; /Brookhaven

    2010-08-01

    As a part of a feasibility study of using the Fermilab Electron Cooler for a low-energy Relativistic Heavy Ion Collider (RHIC) run at Brookhaven National Laboratory (BNL), the cooler operation at 1.6 MeV electron beam energy was tested in a short beam line configuration. The main result of the study is that the cooler beam generation system is suitable for BNL needs. In a striking difference with running 4.3 MeV beam, no unprovoked beam recirculation interruptions were observed.

  14. “Jones-ing” for a Solution: Commercial Street Surveillance and Privacy Torts in Canada

    Directory of Open Access Journals (Sweden)

    Stuart Hargreaves

    2014-07-01

    Full Text Available While street surveillance technologies such as Google Street View are deployed with no discriminatory intent, there is selective scrutiny applied to the published imagery by the anonymous crowd. Disproportionately directed at women and members of ethnic minority groups, this scrutiny means the social risks of street surveillance are not equal. This paper considers the possibility of invasion of privacy actions in tort brought against the commercial service provider as a possible solution. Analysis suggests that Canadian law has evolved in a way such that it is exceedingly difficult to make a claim for “privacy” in tort when the plaintiff is located in public space. This evolution exists in order to ensure that innocuous behavior not be rendered actionable. Furthermore, conceptual reasons exist to suggest that actions in tort are unlikely to be the best solution to the problems posed by commercial street surveillance. While any individual case of embarrassment or nuisance matters, broader “macro-harms” that impact entire communities reflect perhaps the most serious problem associated with the selective scrutiny of street surveillance imagery. Yet, it seems difficult to justify attaching liability for those harms to the commercial providers. While limits need to be placed on the operation of these street surveillance programmes, it is unlikely that invasion of privacy actions are the most effective way to achieve that goal.

  15. Addressing Water Consumption of Evaporative Coolers with Greywater

    Energy Technology Data Exchange (ETDEWEB)

    Sahai, Rashmi [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Shah, Nihar [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Phadke, Amol [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-07-01

    Evaporative coolers (ECs) provide significant gains in energy efficiency compared to vapor compression air conditioners, but simultaneously have significant onsite water demand. This can be a major barrier to deployment in areas of the world with hot and arid climates. To address this concern, this study determined where in the world evaporative cooling is suitable, the water consumption of ECs in these cities, and the potential that greywater can be used reduce the consumption of potable water in ECs. ECs covered 69percent of the cities where room air conditioners are may be deployed, based on comfort conditions alone. The average water consumption due to ECs was found to be 400 L/household/day in the United States and Australia, with the potential for greywater to provide 50percent this amount. In the rest of the world, the average water consumption was 250 L/household/day, with the potential for greywater to supply 80percent of this amount. Home size was the main factor that contributed to this difference. In the Mediterranean, the Middle East, Northern India, and the Midwestern and Southwestern United States alkalinity levels are high and water used for bleeding will likely contribute significantly to EC water consumption. Although technically feasible, upfront costs for household GW systems are currently high. In both developed and developing parts of the world, however, a direct EC and GW system is cost competitive with conventional vapor compression air conditioners. Moreover, in regions of the world that face problems of water scarcity the benefits can substantially outweigh the costs.

  16. Pühendusega isadele - Baker Street

    Index Scriptorium Estoniae

    2009-01-01

    Üritusest 7. novembril Kuressaares Arensburg lounge-restoranis Muusa toimuvast isadepäevahõngulisest üritusest, esinevad Virgo Veldi & Band kavaga "Baker Street", erikülalisena Villu Veski. Saksofonistist Virgo Veldist

  17. Marking Streets to Improve Parking Density

    CERN Document Server

    Xu, Chao

    2015-01-01

    Street parking spots for automobiles are a scarce commodity in most urban environments. The heterogeneity of car sizes makes it inefficient to rigidly define fixed-sized spots. Instead, unmarked streets in cities like New York leave placement decisions to individual drivers, who have no direct incentive to maximize street utilization. In this paper, we explore the effectiveness of two different behavioral interventions designed to encourage better parking, namely (1) educational campaigns to encourage parkers to "kiss the bumper" and reduce the distance between themselves and their neighbors, or (2) painting appropriately-spaced markings on the street and urging drivers to "hit the line". Through analysis and simulation, we establish that the greatest densities are achieved when lines are painted to create spots roughly twice the length of average-sized cars. Kiss-the-bumper campaigns are in principle more effective than hit-the-line for equal degrees of compliance, although we believe that the visual cues of...

  18. Pühendusega isadele - Baker Street

    Index Scriptorium Estoniae

    2009-01-01

    Üritusest 7. novembril Kuressaares Arensburg lounge-restoranis Muusa toimuvast isadepäevahõngulisest üritusest, esinevad Virgo Veldi & Band kavaga "Baker Street", erikülalisena Villu Veski. Saksofonistist Virgo Veldist

  19. Hiding in Plain Sight: Street artists online

    Directory of Open Access Journals (Sweden)

    Kim Barbour

    2013-10-01

    Full Text Available Identity and privacy concerns related to social media are the subject of widespread academic enquiry and mass media reporting. Although in most circumstances academic research tends to present identity play and online self­presentation as positive, media reporting in Australia makes much of the risks of identity theft, privacy breaches and online predators. This research explores the phenomenological experience of creating an online persona, focusing particularly on street artists. For street artists, the threat of unwanted exposure has to be balanced with the positive implications of sharing their creative work outside its geographical and temporal constraints. I argue that street artists use complex persona­creation strategies in order to both protect and promote themselves. The two street artists discussed in this article experience their engagement with social media and digital networks in ways that offer new insight into the opportunities and problems associated with the presentation of a persona online.

  20. F&G Street Marsh Contaminants Investigation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — F&G Street Marsh, located in San Diego Bay National Wildlife Refuge, Chula Vista, San Diego, California, is a tidally influenced wetland providing habitat for...

  1. Numerical study on interaction of local air cooler with stratified hydrogen cloud in a large vessel

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Z. [Atomic Energy of Canada Limited, Chalk River Laboratories, ON K0J 1J0 (Canada); Andreani, M. [Laboratory for Thermal-Hydraulics, Paul Scherrer Institut, 5232 Villigen (Switzerland)

    2012-07-01

    Within the framework of the ERCOSAM project, planning calculations are performed to examine sensitivity parameters that can affect the break-up (erosion) of a helium layer by mitigation devices (i.e., cooler, spray, or Passive Autocatalytic Recombiner - PAR). This paper reports the GOTHIC analysis results for the cooler tests to be performed in the PANDA facility. The cooler elevation and geometry, helium layer thickness, steam distribution in the vessel, and the vessel geometry (inter-connected multi-compartments versus a single volume) on the erosion process as well as the cooling capacity are studied. This analysis is valuable because only a limited number of conditions will be examined in the planned experiments. The study provides a useful understanding of the interaction of a cooler with a stratified atmosphere. (authors)

  2. Effects of temperature conditions in a gas collector on operation of primary and secondary gas coolers

    Energy Technology Data Exchange (ETDEWEB)

    Chuishchev, V.M.; Selivanova, Z.G.; Vasyuta, V.I.

    1988-04-01

    Discusses composition of coal gas leaving coke ovens and temperature effects on its composition in a gas collector and cooling systems. Effects of coal gas temperature ranging from 78 to 90 C on operation of cooling systems are analyzed: cooling intensity, naphthalene buildup, etc. Analyses show that coal gas temperature fluctuations from 80 to 90 C do not influence gas collector operation, whereas operation of primary gas coolers is influenced by gas collector operation. When coal gas temperature is reduced from 88 to 80 C intensity of coal tar accumulation increases 2 times and that of naphthalene increases 5 to 6 times. Temperature of coal gas leaving the primary coolers ranges from 35 to 40 C. Types of primary coal gas coolers, their operation and performance are comparatively evaluated. Effects of gas cooler design on efficiency of coal tar separation from coal gas are discussed. 5 refs.

  3. Modeling of a regenerative indirect evaporative cooler for a desiccant cooling system

    DEFF Research Database (Denmark)

    Bellemo, Lorenzo; Elmegaard, Brian; Reinholdt, Lars O.;

    This paper presents a numerical study of a regenerative indirect evaporative cooler, the so-called Dew Point Cooler (DPC), which is part of a Desiccant Cooling system that may both dehumidify and cool humid air. The DPC model is based on first principles using a 1D finite volume scheme and determ......This paper presents a numerical study of a regenerative indirect evaporative cooler, the so-called Dew Point Cooler (DPC), which is part of a Desiccant Cooling system that may both dehumidify and cool humid air. The DPC model is based on first principles using a 1D finite volume scheme...... and determines the steady state working conditions for the component. A sensitivity analysis of the DPC performance is carried out based on the air inlet conditions, air flow rate and recirculation fraction. A recirculation fraction around 0.3 maximizes the DPC net cooling capacity. The supply temperature...

  4. TRAFFIC EMISSION TRANSPORTATION IN STREET CANYONS

    Institute of Scientific and Technical Information of China (English)

    XIE Xiao-min; WANG Jia-song; HUANG Zhen

    2009-01-01

    Spatial distributions of traffic-related pollutants in street canyons were investigated by field measurements and Computational Fluid Dynamics(CFD).Two typical street canyons were selected for field monitoring,and a three-dimensional numerical model was built based on Reynolds-averaged Navier-Stokes equations equipped with the standard k-ε turbulence models for CFD simulations.The study shows that the pollutant concentrations of vehicle emission correlate well with the traffic volume variation,wind direction and wind speed.The wind direction and speed at the roof level determine overwhellmingly the flow field and the distributions of pollutant concentrations in the street canyon.When the wind speed is equal to zero,the pollutant concentrations on the breath height of the both sides of the street canyon are almost the same.When the wind direction is perpendicular to the street,one main vortex is formed with a shape depending on the building structure on both sides of the street,the pollutant is accumulated on the leeward side,and the pollutant concentrations at the breath height on the leeward side are 2 to 3 times as those at the breath height on the windward side.If the wind direction makes some angles with the street canyon,the pollutant concentration will be higher on the leeward side because one main vortex will also be formed in the vertical section of the canyon by the perpendicular component of the wind.But pollutant concentrations decrease in the canyon because pollutants are dispersed along the axis of the street.Pollutants at different heights of the vertical section decrease with height,i.e.there are concentration gradients in the vertical section,and the pollutant concentrations on the leeward side of the upstream building are much higher than those on the windward side of the downstream building.

  5. Explaining temporal patterns in street robbery

    OpenAIRE

    Tompson, L. A.

    2016-01-01

    This thesis is concerned with explaining spatio-temporal patterns in street robbery through the lens of environmental criminology. The research question ‘what makes a place criminogenic for street robbery at some times and not others?’ is used to frame seven hypotheses. These centre on some of the features of the natural and built environment that can be considered criminogenic (i.e. crime producing). Specifically, the hypotheses test the time-varying influence of darkness, weather conditions...

  6. OpenStreetMap over WMS

    Directory of Open Access Journals (Sweden)

    Přemysl Vohnout

    2010-02-01

    Full Text Available This paper discuss the issues which we faced, while preparing WMS server with OpenStreetMap data of whole Europe. This article is divided into three sections. First is about mandatory applications which are required for working WMS service with OpenStreetMap data. Second is focused on tuning up PostgreSQL. Third is focused on rendering time improvement of layers.

  7. Integrated testing of the Thales LPT9510 pulse tube cooler and the iris LCCE electronics

    Science.gov (United States)

    Johnson, Dean L.; Rodriguez, Jose I.; Carroll, Brian A.; Bustamante, John G.; Kirkconnell, Carl S.; Luong, Thomas T.; Murphy, J. B.; Haley, Michael F.

    2014-01-01

    The Jet Propulsion Laboratory (JPL) has identified the Thales LPT9510 pulse tube cryocooler as a candidate low cost cryocooler to provide active cooling on future cost-capped scientific missions. The commercially available cooler can provide refrigeration in excess of 2 W at 100K for 60W of power. JPL purchased the LPT9510 cooler for thermal and dynamic performance characterization, and has initiated the flight qualification of the existing cooler design to satisfy near-term JPL needs for this cooler. The LPT9510 has been thermally tested over the heat reject temperature range of 0C to +40C during characterization testing. The cooler was placed on a force dynamometer to measure the selfgenerated vibration of the cooler. Iris Technology has provided JPL with a brass board version of the Low Cost Cryocooler Electronics (LCCE) to drive the Thales cooler during characterization testing. The LCCE provides precision closed-loop temperature control and embodies extensive protection circuitry for handling and operational robustness; other features such as exported vibration mitigation and low frequency input current filtering are envisioned as options that future flight versions may or may not include based upon the mission requirements. JPL has also chosen to partner with Iris Technology for the development of electronics suitable for future flight applications. Iris Technology is building a set of radiation-hard, flight-design electronics to deliver to the Air Force Research Laboratory (AFRL). Test results of the thermal, dynamic and EMC testing of the integrated Thales LPT9510 cooler and Iris LCCE electronics is presented here.

  8. Re-Design Lube Oil Cooler pada Turbin Gas dengan Analisa Termodinamika dan Perpindahan Panas

    Directory of Open Access Journals (Sweden)

    Siti Duratun Nasiqiati Rosady

    2014-09-01

    Full Text Available Pada sebuah pembangkit listrik tenaga gas, sistem pelumasan turbin sangat diperlukan. Pelumas yang telah digunakan didinginkan kembali menggunakan lube oil cooler. Lube oil cooler merupakan compact heat exchanger tipe circular tubes, continuous fins yang berfungsi sebagai pendingin oli dengan udara sebagai fluida pendingin. Pada kondisi operasional didapatkan bahwa temperatur oli keluar lube oil cooler masih cukup tinggi. Hal ini dapat menyebabkan turbin gas shut down. Berdasarkan kondisi tersebut, maka dilakukan analisa performa lube oil cooler existing dan melakukan redesign untuk meningkatkan effectiveness dari lube oil cooler. Analisa performa lube oil cooler existing meliputi perpindahan panas actual dan effectiveness. Sedangkan redesign dilakukan dengan variasi laju aliran massa fluida dingin (udara dan surface designation berdasarkan standard Compact heat exchangers untuk tipe circular tubes, continuous fins. Dengan batasan yang digunakan dalam perancangan lube oil cooler adalah volume ruang penempatan heat exchanger. Perancangan menggunakan metode LMTD dan NTU meliputi perhitungan perpindahan panas pada sisi tubes dan fins, area perpindahan panas, heat transfer actual, overall heat transfer coefficient serta effectiveness. Dari perhitungan yang telah dilakukan didapatkan effectiveness dari lube oil cooler existing adalah sebesar 13.6%. Berdasarkan analisa redesign, hasil yang memiliki performa paling baik adalah surface designation 8.0-3/8 T dengan laju aliran massa udara 7.5 kg/s dengan temperatur keluar oli sebesar 342.14 K, effectiveness 29%. Adapun detail dimensi redesign adalah jumlah tubes 245, diameter tube 0.0102 m, jumlah fins/ meter 315, transverse pitch 0.022 m dan longitudinal pitch sebesar 0.0254 m.

  9. Integrated testing of the Thales LPT9510 pulse tube cooler and the iris LCCE electronics

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Dean L.; Rodriguez, Jose I.; Carroll, Brian A. [The Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Bustamante, John G. [Georgia Institute of Technology, Atlanta, GA 30332 (United States); Kirkconnell, Carl S.; Luong, Thomas T.; Murphy, J. B.; Haley, Michael F. [Iris Technology, Irvine, CA 92616 (United States)

    2014-01-29

    The Jet Propulsion Laboratory (JPL) has identified the Thales LPT9510 pulse tube cryocooler as a candidate low cost cryocooler to provide active cooling on future cost-capped scientific missions. The commercially available cooler can provide refrigeration in excess of 2 W at 100K for 60W of power. JPL purchased the LPT9510 cooler for thermal and dynamic performance characterization, and has initiated the flight qualification of the existing cooler design to satisfy near-term JPL needs for this cooler. The LPT9510 has been thermally tested over the heat reject temperature range of 0C to +40C during characterization testing. The cooler was placed on a force dynamometer to measure the selfgenerated vibration of the cooler. Iris Technology has provided JPL with a brass board version of the Low Cost Cryocooler Electronics (LCCE) to drive the Thales cooler during characterization testing. The LCCE provides precision closed-loop temperature control and embodies extensive protection circuitry for handling and operational robustness; other features such as exported vibration mitigation and low frequency input current filtering are envisioned as options that future flight versions may or may not include based upon the mission requirements. JPL has also chosen to partner with Iris Technology for the development of electronics suitable for future flight applications. Iris Technology is building a set of radiation-hard, flight-design electronics to deliver to the Air Force Research Laboratory (AFRL). Test results of the thermal, dynamic and EMC testing of the integrated Thales LPT9510 cooler and Iris LCCE electronics is presented here.

  10. Experimental characterization of the Hitrap Cooler trap with highly charged ions.

    OpenAIRE

    Fedotova, Svetlana

    2013-01-01

    The HITRAP (Highly charged Ions TRAP)facility is being set up and commissioned at GSI, Darmstadt. It will provide heavy, highly charged ions at low velocities to high-precision atomic physics experiments. Within this work the Cooler trap- the key element of the HITRAP facility was tested. The Cooler trap was assembled, aligned, and commissioned in trapping experiments with ions from off-line sources.The work performed within the scope of this thesis provided the baseline for further operation...

  11. Frequency stability of a tunable diode laser mounted in a compact Stirling cycle cooler

    Science.gov (United States)

    Durso, Santo S.; May, R. D.; Tuchscherer, M. A.; Webster, C. R.

    1989-01-01

    A tunable diode laser (TDL) has been operated with a compact lightweight closed-cycle Stirling cooler. The laser linewidth has been measured near 80 K and found to be about half of that when using more massive closed-cycle coolers. Novel applications include balloon-borne and aircraft-adapted instruments, where size, weight, and power requirements place stringent demands on necessary TDL cooling systems.

  12. Experimental characterization of the Hitrap Cooler trap with highly charged ions.

    OpenAIRE

    Fedotova, Svetlana

    2013-01-01

    The HITRAP (Highly charged Ions TRAP)facility is being set up and commissioned at GSI, Darmstadt. It will provide heavy, highly charged ions at low velocities to high-precision atomic physics experiments. Within this work the Cooler trap- the key element of the HITRAP facility was tested. The Cooler trap was assembled, aligned, and commissioned in trapping experiments with ions from off-line sources.The work performed within the scope of this thesis provided the baseline for further operation...

  13. Child work in Bogotá streets

    Directory of Open Access Journals (Sweden)

    Ángela María Pinzón, MD, MPH

    2003-12-01

    Full Text Available Title: Child Labor in the Streets of Bogotá.There are many children working in the streetsof Bogotá. The exact number is unknown andthere is very little information available aboutthis group. Methodology: Descriptive study.Children working in certain streets of Bogotáwere surveyed on Saturday July 19th 2003.Results: A total of 162 children were surveyed,52.5% boys and 47.5% girls; 38.5% youngerthen 5 years and 64.2% older; 61.1% were bythemselves and the rest with an adult; 49.4% werechildren of displaced families and the others werechildren of families from Bogotá. A 33.3% rateof school desertion and a rate of 38.9% lack ofsocial security affiliation were found. The lack ofsocial security affiliation is higher in desplaced families and within this group it is higher in thefamilies that have been living a short period oftime in Bogotá. Discusion: Data suggest a strongrelationship between child labor in the street andthe problem of displaced families; a serious impacton school desertion, and long working hoursexposed to various security, phisical, chemical,ergonomic, and psicosocial risk factors. There arethree groups of children working in the streets ofBogotá: Children of displaced families; childrenthat work in the streets, and children that live inthe streets. Conclusions: Child labor in thestreets of Bogotá is a serious problem, whichrequires attention based on knowledge of causesand the pursuit of effective measures for itseradication.

  14. Street Cries and the urban ritornelle

    Directory of Open Access Journals (Sweden)

    Jacob Kreutzfeldt

    2012-04-01

    Full Text Available Street cries, though rarely heard in Northern European cities today, testify to ways in which audible practices shape and structure urban spaces. Paradigmatic for what Gilles Deleuze and Felix Guattari call ‘the refrain’, the ritualised and stylised practice of street cries may point at the dynamics of space-making, through which the social and territorial construction of urban space is performed. The article draws on historical material, documenting and describing street cries, particularly in Copenhagen in the years 1929 to 1935. Most notably, the composer Vang Holmboe and the architect Steen Eiler Rasmussen have investigated Danish street cries as a musical and a spatial phenomenon, respectably. Such studies – from their individual perspectives – can be said to explore the aesthetics of urban environments, since street calls are developed and heard specifically in the context of the city. Investigating the different methods employed in the two studies and presenting Deleuze and Guattari’s theory of the refrain as a framework for further studies in the field, this article seeks to outline a fertile area of study for sound studies: the investigation of everyday refrains and the environmental relations they express and perform. Today changed sensibilities and technologies have rendered street crying obsolete in Northern Europe, but new urban ritornells may have taken their place.

  15. Development of Two-Stage Stirling Cooler for ASTRO-F

    Science.gov (United States)

    Narasaki, K.; Tsunematsu, S.; Ootsuka, K.; Kyoya, M.; Matsumoto, T.; Murakami, H.; Nakagawa, T.

    2004-06-01

    A two-stage small Stirling cooler has been developed and tested for the infrared astronomical satellite ASTRO-F that is planned to be launched by Japanese M-V rocket in 2005. ASTRO-F has a hybrid cryogenic system that is a combination of superfluid liquid helium (HeII) and two-stage Stirling coolers. The mechanical cooler has a two-stage displacer driven by a linear motor in a cold head and a new linear-ball-bearing system for the piston-supporting structure in a compressor. The linear-ball-bearing supporting system achieves the piston clearance seal, the long piston-stroke operation and the low frequency operation. The typical cooling power is 200 mW at 20 K and the total input power to the compressor and the cold head is below 90 W without driver electronics. The engineering, the prototype and the flight models of the cooler have been fabricated and evaluated to verify the capability for ASTRO-F. This paper describes the design of the cooler and the results from verification tests including cooler performance test, thermal vacuum test, vibration test and lifetime test.

  16. 150K - 200K miniature pulse tube cooler for micro satellites

    Energy Technology Data Exchange (ETDEWEB)

    Chassaing, Clément; Butterworth, James; Aigouy, Gérald [Air Liquide Advanced Technologies (AL-AT) - 38360 Sassenage (France); Daniel, Christophe [Centre National D' Etudes Spatiales (CNES) - 31401 Toulouse (France); Crespin, Maurice; Duvivier, Eric [STEEL électronique - 31220 Martres Tolosane (France)

    2014-01-29

    Air Liquide is working with the CNES and Steel électronique in 2013 to design, manufacture and test a Miniature Pulse Tube Cooler (MPTC) to cool infrared detectors for micro-satellite missions. The cooler will be particularly adapted to the needs of the CNES MICROCARB mission to study atmospheric Carbon Dioxide which presents absorption lines in the thermal near infrared, at 1.6 μm and 2.0 μm. The required cooler temperature is from 150 to 200K with cooling power between 1 and 3 watts. The overall electrical power budget including electronics is less than 20W with a 288-300K rejection temperature. Particular attention is therefore paid to optimizing overall system efficiency. The active micro vibration reduction system and thermal control systems already developed for the Air Liquide Large Pulse Tube Cooler (LPTC) are currently being implemented into a new high efficiency electronic architecture. The presented work concerns the new cold finger and electronic design. The cooler uses the compressor already developed for the 80K Miniature Pulse Tube Cryocooler. This Pulse Tube Cooler addresses the requirements of space missions where extended continuous operating life time (>5 years), low mass and low micro vibration levels are critical.

  17. CFD modeling of stripper ash cooler of circulating fluidized bed boiler

    Directory of Open Access Journals (Sweden)

    Ravi Inder Singh

    2016-09-01

    Full Text Available The stable operation of a bottom ash cooler is vital for the operation of the circulating fluidized bed boiler. To assess, the stability of the ash cooler, it is important to have a thorough understanding of the flow behaviour. Although, many experimental results been reported in literature, CFD modelling of the ash cooler has not been carried out. In this paper, the transient computational analysis of a novel stripper ash cooler has been carried out using the Eulerian–Eulerian multiphase approach. The phase coupled SIMPLE algorithm has been used to solve the multiphase equations and the Gidaspow drag model has been employed to model the interaction between the fluidized air and ash. Two cases have been analysed in this paper. In the first case, the filling of the ash in the cooler has been analysed and in the second case, the phenomenon of fluidized bed bubbling in the ash cooler has been simulated. The study the of flow characteristics of hot ash has been studied. The contours of temperature, phase volume and bubbling have been analyzed in this paper.

  18. Performance investigation of capillary tubes for machine tool coolers retrofitted with HFC-407C refrigerant

    Science.gov (United States)

    Wang, Fujen; Chang, Tongbou; Chiang, Weiming; Lee, Haochung

    2012-09-01

    The machine tool coolers are the best managers of coolant temperature in avoiding the deviation of spindle centerline for machine tools. However, the machine coolers are facing the compressed schedule to phase out the HCFC (hydro-chloro-floro-carbon) refrigerant and little attention has been paid to comparative study on sizing capillary tube for retrofitted HFC (hydro-floro-carbon) refrigerant. In this paper, the adiabatic flow in capillary tube is analyzed and modeled for retrofitting of HFC-407C refrigerant in a machine tool cooler system. A computer code including determining the length of sub-cooled flow region and the two phase region of capillary tube is developed. Comparative study of HCFC-22 and HFC-407C in a capillary tube is derived and conducted to simplify the traditional trial-and-error method of predicting the length of capillary tubes. Besides, experimental investigation is carried out by field tests to verify the simulation model and cooling performance of the machine tool cooler system. The results from the experiments reveal that the numerical model provides an effective approach to determine the performance data of capillary tube specific for retrofitting a HFC-407C machine tool cooler. The developed machine tool cooler system is not only directly compatible with new HFC-407C refrigerant, but can also perform a cost-effective temperature control specific for industrial machines.

  19. Performance improvement of double-tube gas cooler in CO2 refrigeration system using nanofluids

    Directory of Open Access Journals (Sweden)

    Sarkar Jahar

    2015-01-01

    Full Text Available The theoretical analyses of the double-tube gas cooler in transcritical carbon dioxide refrigeration cycle have been performed to study the performance improvement of gas cooler as well as CO2 cycle using Al2O3, TiO2, CuO and Cu nanofluids as coolants. Effects of various operating parameters (nanofluid inlet temperature and mass flow rate, CO2 pressure and particle volume fraction are studied as well. Use of nanofluid as coolant in double-tube gas cooler of CO2 cycle improves the gas cooler effectiveness, cooling capacity and COP without penalty of pumping power. The CO2 cycle yields best performance using Al2O3-H2O as a coolant in double-tube gas cooler followed by TiO2-H2O, CuO-H2O and Cu-H2O. The maximum cooling COP improvement of transcritical CO2 cycle for Al2O3-H2O is 25.4%, whereas that for TiO2-H2O is 23.8%, for CuO-H2O is 20.2% and for Cu-H2O is 16.2% for the given ranges of study. Study shows that the nanofluid may effectively use as coolant in double-tube gas cooler to improve the performance of transcritical CO2 refrigeration cycle.

  20. Effect of sinter layer porosity distribution on flow and temperature fields in a sinter cooler

    Institute of Scientific and Technical Information of China (English)

    Jik-chang Leong; Kai-wun Jin; Jia-shyan Shiau; Tzer-ming Jeng; Chang-hsien Tai

    2009-01-01

    When sinters are filled into the sinter cooler from the sintering machine, it is commonly seen that, due to segregation ef-fects, sinters of larger size usually accumulate closer to the inner wall of the sinter cooler, whereas those of smaller size are to the outer wall. This nonuniform distribution of sinters has led to uneven cooling effect throughout the cooler. This causes the sinters leaving the cooler at a large temperature difference. This undesired temperature difference leads to the deformation and even the de-struction of the conveyors. The computational fluid dynamics (CFD) technique was used in the present work to investigate the heat and fluid flow phenomena within the sinter cooler corresponding to the different distribution of sinter layer porosity, which was highly dependent on the arrangement and orientation of sinters within the sinter cooler. It is confirmed that a high mass flow rate within the sinter layer causes a low temperature region and vice versa. The flow fields for vertically reducing porosity distribution and random distribution are almost identical indicating the relative insignificance of convective heat transfer mechanism.

  1. Public Reactions to New Street Tree Planting

    Directory of Open Access Journals (Sweden)

    Ruth A. Rae

    2010-01-01

    Full Text Available MillionTreesNYC, which has the goal of planting one million trees in New York City by 2017, is intended to make New York City a greener, more sustainable city and is part of the Mayor’s comprehensive long term strategic plan, PlaNYC. Through planting a tree at every suitable sidewalk location in the city, the City of New York is transforming blocks and communities, and providing a variety of environmental, social and aesthetic benefits. This article examines the large scale municipal planting of new street trees and the reaction by some of the pubic to this planting.Trees offer benefits to the city overall, but the public may not understand these benefits or the street tree planting process. Between 2007 and 2009, the Department of Parks & Recreation planted 53,235 new street trees, and received 4,108 items of correspondence from the public. The majority of this correspondence consisted of public comments about the City’s new street tree planting policies and processes including placement objections, maintenance concerns, reports of resultant damage from tree planting operations, requests for new street trees and reports of tree conditions.This study describes the operational policies that guide New York City's municipal street tree planting, and results of content and spatial analysis of the correspondence. Qualitative analysis of the correspondence revealed the public perceptions and concerns related to the MillionTreesNYC program. Spatial analysis explored the relationship between the planting locations of new street trees and the locations of the citizen correspondence.Public reactions to this large scale municipal planting are related to the dual public and private nature of the sidewalk, issues of territoriality, responsibility, aesthetics and place attachment. Correspondence volume was associated with the scale of the new street tree block planting program, and the effectiveness of NYC’s 311 Customer Service Center. The discussion

  2. Temperature and human thermal comfort effects of street trees across three contrasting street canyon environments

    Science.gov (United States)

    Coutts, Andrew M.; White, Emma C.; Tapper, Nigel J.; Beringer, Jason; Livesley, Stephen J.

    2016-04-01

    Urban street trees provide many environmental, social, and economic benefits for our cities. This research explored the role of street trees in Melbourne, Australia, in cooling the urban microclimate and improving human thermal comfort (HTC). Three east-west (E-W) oriented streets were studied in two contrasting street canyon forms (deep and shallow) and between contrasting tree canopy covers (high and low). These streets were instrumented with multiple microclimate monitoring stations to continuously measure air temperature, humidity, solar radiation, wind speed and mean radiant temperature so as to calculate the Universal Thermal Climate Index (UTCI) from May 2011 to June 2013, focusing on summertime conditions and heat events. Street trees supported average daytime cooling during heat events in the shallow canyon by around 0.2 to 0.6 °C and up to 0.9 °C during mid-morning (9:00-10:00). Maximum daytime cooling reached 1.5 °C in the shallow canyon. The influence of street tree canopies in the deep canyon was masked by the shading effect of the tall buildings. Trees were very effective at reducing daytime UTCI in summer largely through a reduction in mean radiant temperature from shade, lowering thermal stress from very strong (UTCI > 38 °C) down to strong (UTCI > 32 °C). The influence of street trees on canyon air temperature and HTC was highly localized and variable, depending on tree cover, geometry, and prevailing meteorological conditions. The cooling benefit of street tree canopies increases as street canyon geometry shallows and broadens. This should be recognized in the strategic placement, density of planting, and species selection of street trees.

  3. Playing with the city: street art and videogames/Jugando con la ciudad: street art y videojuegos

    National Research Council Canada - National Science Library

    Israel Márquez; Susana Tosca

    2017-01-01

    ... culture. Keywords: Street art; graffiti; videogames; play; city. [es] Jugando con la ciudad: street art y videojuegos Resumen. En este artículo se presenta y describe el fenómeno del street art inspirado en videojuegos como un tipo específico de street art. Se considera su materialidad e importancia, y se conceptualiza a partir de una doble mani...

  4. Reflecting reflection in supervision

    DEFF Research Database (Denmark)

    Lystbæk, Christian Tang

    Reflection has moved from the margins to the mainstream in supervision. Notions of reflection have become well established since the late 1980s. These notions have provided useful framing devices to help conceptualize some important processes in guidance and counseling. However, some applications...

  5. From the street to the store. The formalization of street vendors in Quito, Ecuador

    NARCIS (Netherlands)

    S. Ferragut (Sergio); G.M. Gómez (Georgina)

    2013-01-01

    markdownabstract__Abstract__ With the support of local and international organisations, the municipality of Quito, Ecuador, relocated approximately 6000 street vendors from the streets to eleven Popular Commercial Centres. The research examines the extent to which formalisation has al-tered their

  6. Road and Street Centerlines - COUNTY_STREET_CENTERLINES_IDHS_IN: Street Centerlines Maintained by County Agencies in Indiana (Indiana Department of Homeland Security, Line Shapefile)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — COUNTY_STREET_CENTERLINES_IDHS_IN is a line shapefile that contains street centerlines maintained by county agencies in Indiana, provided by personnel of Indiana...

  7. Road and Street Centerlines - COUNTY_STREET_CENTERLINES_IDHS_IN: Street Centerlines Maintained by County Agencies in Indiana (Indiana Department of Homeland Security, Line Shapefile)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — COUNTY_STREET_CENTERLINES_IDHS_IN is a line feature class that contains street centerlines maintained by county agencies in Indiana, provided by personnel of Indiana...

  8. Road and Street Centerlines - COUNTY_STREET_CENTERLINES_IDHS_IN: Street Centerlines Maintained by County Agencies in Indiana (Indiana Department of Homeland Security, Line Shapefile)

    Data.gov (United States)

    NSGIC State | GIS Inventory — COUNTY_STREET_CENTERLINES_IDHS_IN is a line feature class that contains street centerlines maintained by county agencies in Indiana, provided by personnel of Indiana...

  9. [Street children and AIDS in Haiti].

    Science.gov (United States)

    Bernier, M; Ascensio, P

    1995-01-01

    This study is a qualitative inquiry KAP about sexuality, and adoption and preservation of safe sexual behaviors, among the children of the street in Port-au-Prince, Haiti. Three groups of participating children of the street were observed in Port-au-Prince for three months, during June through August 1991. The information was collected with the use of pre-tested charts for each theme chosen. Then, individual interviews were conducted with leaders identified among the educators and children of the street. One of the main goals of Aids educational programs of street children should be to make them believe in the existence of the disease, and the real risk it poses for death. The strategies that we will use to convince them should deal with the different social, psychological, economical, and environmental factors that characterized the children as follows: 1) their adherence to a peer group and the relationship of power between the older and younger children; 2) the fundamental importance of money in their life, and that all relationships that they have are based on the capacity of people to give them something, such as money; 3) the role of their social appearance and their need to behave like other children for even one day; 4) their low self-esteem; 5) their feeling of powerlessness and resignation related to their living conditions; 6) the influence of the street culture; and 7) their understanding of sexuality as an immediate pleasure.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Street Theater and Subject Formation in Wartime China: Toward a New Form of Public Art

    Directory of Open Access Journals (Sweden)

    Xiaobing Tang

    2016-03-01

    Full Text Available Based on archival research, this article presents a succinct history of the street theater movement in China through the 1930s. It examines how complex discourses and competing visions, as well as historical events and practices—in particular the War of Resistance against Japan—both shaped and propelled the movement. The author focuses on theoretical and practical issues that promoters and practitioners of street theater dealt with and reflected on in three succeeding stages. Observing that the street theater movement hastened the formation of a modern national imagination, the author argues that the movement presented a paradigmatic development as it foregrounded the imperative to engage rural China as well as the need for participants to acquire new subject positions.

  11. Notes on LED Installations in Street Illumination

    Directory of Open Access Journals (Sweden)

    Elisabeta Spunei

    2014-09-01

    Full Text Available The paper presents a study made on choosing LED street lighting installations, such that the quality requirements for exterior artificial lighting are fulfilled. We analyze two types of LED street lighting installations from a technical point of view, together with lighting level and brightness values obtained during the measurements. Following on the field measurements, the lighting quality parameters are calculated, and, for the lighting installation with the best performance, optimal mounting suggestions are made. The optimal quality parameters are calculated by simulations using the Dialux software. The same software and the same light sources we also compute an optimal street lighting by determining the size of the installation that provides the best lighting parameter values.

  12. Turbulent ventilation of a street canyon

    DEFF Research Database (Denmark)

    Nielsen, Morten

    2000-01-01

    A selection of turbulence data corresponding to 185 days of field measurements has een analysed. The non-ideal building geometry influenced the circulation patterns in the street canyon and the largest average vertical velocities were observed in the wake of an unbroken line of buildings. The sta......A selection of turbulence data corresponding to 185 days of field measurements has een analysed. The non-ideal building geometry influenced the circulation patterns in the street canyon and the largest average vertical velocities were observed in the wake of an unbroken line of buildings...... small, and this suggests that most of the velocity fluctuations were fairly local and not caused by unsteady street vortices. The observed velocities scaled with the ambient wind speed except under low-wind conditions....

  13. Street canyon ventilation and atmospheric turbulence

    Science.gov (United States)

    Salizzoni, P.; Soulhac, L.; Mejean, P.

    Operational models for pollutant dispersion in urban areas require an estimate of the turbulent transfer between the street canyons and the overlying atmospheric flow. To date, the mechanisms that govern this process remain poorly understood. We have studied the mass exchange between a street canyon and the atmospheric flow above it by means of wind tunnel experiments. Fluid velocities were measured with a Particle Image Velocimetry system and passive scalar concentrations were measured using a Flame Ionisation Detector. The mass-transfer velocity between the canyon and the external flow has been estimated by measuring the cavity wash-out time. A two-box model, used to estimate the transfer velocity for varying dynamical conditions of the external flow, has been used to interpret the experimental data. This study sheds new light on the mechanisms which drive the ventilation of a street canyon and illustrates the influence of the external turbulence on the transfer process.

  14. Magnetic properties of street dust and topsoil in Beijing and its environmental implications

    Institute of Scientific and Technical Information of China (English)

    ZHENG Yan; ZHANG ShiHong

    2008-01-01

    Environmental magnetic measurements were carried out on the samples of street dust and topsoil, which were collected along the roadway in the urban and suburb of Beijing, including magnetic sus-ceptibility (χ), anhysteretic remanent magnetization (ARM), isothermal remanent magnetization (IRM) of all samples and temperature-dependence of magnetic susceptibilities and magnetic hysteresis pa-rameters of representative samples. Obvious differences exist between the samples of street dust and those of topsoil. Compared with topsoil samples, the concentration of magnetic particles and high-coercivity components in street dust samples are higher, and the magnetic grains are coarser. Both dust and topsoil samples are dominated by ferrimagnetic minerals, and iron particles are only detected in some dust samples. These results suggest that street dust samples reflect the characteris-tic of particles produced by industrial and traffic activities, and the magnetic property of topsoil sam-ples represents the characteristic of particles from both anthropogenic and natural sources. The dis-tribution of magnetic parameters is influenced by the environment where the samples are collected, like industry, traffic density and other rOad conditions. Hard isothermal remanent magnetization (HIRM) may be used as an indicator of particles produced by traffic activity. Dust storm samples collected on 17 and 18 April, 2006 have different magnetic properties from street dust and natural particles, like loess and paleosol, which indicate that the dust storm might be mixed with anthropogenic particulates during transport and falling.

  15. Practical issues in adopting a traveling wave thermoacoustic cooler for use in a food storage refrigerator

    Science.gov (United States)

    Spoor, Philip S.

    2005-09-01

    CFIC/QDrive has developed a food storage refrigerator for the Army based on thermoacoustic technology. This ``Phase II'' SBIR project is a continuation of a ``Phase I'' effort that explored using a standing-wave thermoacoustic cooler for the refrigerator. The standing-wave cooler was found to be too inefficient with too low a power density to be practical, so it was switched to an acoustic Stirling, or traveling-wave thermoacoustic (regenerator based) cooler for Phase II. The major challenges of this project were adapting the Stirling-style cooler to a food storage application, and not the fundamentals of the cooler itself (the one exception being the issue of acoustic streaming). The challenges include: Running at 60 Hz (without frequency-shifting electronics), heat exchange without circulating fluids, dynamic balance, guarantee of long life, efficiency, and compactness (power density). How these challenges were met and how they drove the design, in most cases away from what would be ideal for the cycle itself, will be discussed. Time permitting, how the additional pressure of low unit cost would affect this type of product development will also be discussed. [Research supported by the U. S. Army through a Small Business Innovation Research (SBIR) grant.

  16. CFD analysis of turboprop engine oil cooler duct for best rate of climb condition

    Science.gov (United States)

    Kalia, Saurabh; CA, Vinay; Hegde, Suresh M.

    2016-09-01

    Turboprop engines are widely used in commuter category airplanes. Aircraft Design bureaus routinely conduct the flight tests to confirm the performance of the system. The lubrication system of the engine is designed to provide a constant supply of clean lubrication oil to the engine bearings, the reduction gears, the torque-meter, the propeller and the accessory gearbox. The oil lubricates, cools and also conducts foreign material to the oil filter where it is removed from further circulation. Thus a means of cooling the engine oil must be provided and a suitable oil cooler (OC) and ducting system was selected and designed for this purpose. In this context, it is relevant to study and analyse behaviour of the engine oil cooler system before commencing actual flight tests. In this paper, the performance of the oil cooler duct with twin flush NACA inlet housed inside the nacelle has been studied for aircraft best rate of climb (ROC) condition using RANS based SST K-omega model by commercial software ANSYS Fluent 13.0. From the CFD analysis results, it is found that the mass flow rate captured and pressure drop across the oil cooler for the best ROC condition is meeting the oil cooler manufacturer requirements thus, the engine oil temperature is maintained within prescribed limits.

  17. Thermal design of two-stage evaporative cooler based on thermal comfort criterion

    Science.gov (United States)

    Gilani, Neda; Poshtiri, Amin Haghighi

    2017-04-01

    Performance of two-stage evaporative coolers at various outdoor air conditions was numerically studied, and its geometric and physical characteristics were obtained based on thermal comfort criteria. For this purpose, a mathematical model was developed based on conservation equations of mass, momentum and energy to determine heat and mass transfer characteristics of the system. The results showed that two-stage indirect/direct cooler can provide the thermal comfort condition when outdoor air temperature and relative humidity are located in the range of 34-54 °C and 10-60 %, respectively. Moreover, as relative humidity of the ambient air rises, two-stage evaporative cooler with the smaller direct and larger indirect cooler will be needed. In building with high cooling demand, thermal comfort may be achieved at a greater air change per hour number, and thus an expensive two-stage evaporative cooler with a higher electricity consumption would be required. Finally, a design guideline was proposed to determine the size of required plate heat exchangers at various operating conditions.

  18. Reliability improvements on Thales RM2 rotary Stirling coolers: analysis and methodology

    Science.gov (United States)

    Cauquil, J. M.; Seguineau, C.; Martin, J.-Y.; Benschop, T.

    2016-05-01

    The cooled IR detectors are used in a wide range of applications. Most of the time, the cryocoolers are one of the components dimensioning the lifetime of the system. The cooler reliability is thus one of its most important parameters. This parameter has to increase to answer market needs. To do this, the data for identifying the weakest element determining cooler reliability has to be collected. Yet, data collection based on field are hardly usable due to lack of informations. A method for identifying the improvement in reliability has then to be set up which can be used even without field return. This paper will describe the method followed by Thales Cryogénie SAS to reach such a result. First, a database was built from extensive expertizes of RM2 failures occurring in accelerate ageing. Failure modes have then been identified and corrective actions achieved. Besides this, a hierarchical organization of the functions of the cooler has been done with regard to the potential increase of its efficiency. Specific changes have been introduced on the functions most likely to impact efficiency. The link between efficiency and reliability will be described in this paper. The work on the two axes - weak spots for cooler reliability and efficiency - permitted us to increase in a drastic way the MTTF of the RM2 cooler. Huge improvements in RM2 reliability are actually proven by both field return and reliability monitoring. These figures will be discussed in the paper.

  19. Thermal design of two-stage evaporative cooler based on thermal comfort criterion

    Science.gov (United States)

    Gilani, Neda; Poshtiri, Amin Haghighi

    2016-09-01

    Performance of two-stage evaporative coolers at various outdoor air conditions was numerically studied, and its geometric and physical characteristics were obtained based on thermal comfort criteria. For this purpose, a mathematical model was developed based on conservation equations of mass, momentum and energy to determine heat and mass transfer characteristics of the system. The results showed that two-stage indirect/direct cooler can provide the thermal comfort condition when outdoor air temperature and relative humidity are located in the range of 34-54 °C and 10-60 %, respectively. Moreover, as relative humidity of the ambient air rises, two-stage evaporative cooler with the smaller direct and larger indirect cooler will be needed. In building with high cooling demand, thermal comfort may be achieved at a greater air change per hour number, and thus an expensive two-stage evaporative cooler with a higher electricity consumption would be required. Finally, a design guideline was proposed to determine the size of required plate heat exchangers at various operating conditions.

  20. Electronic coolers based on superconducting tunnel junctions: fundamentals and applications

    OpenAIRE

    2014-01-01

    International audience; Thermo-electric transport at the nano-scale is a rapidly developing topic, in particular in superconductor-based hybrid devices. In this review paper, we first discuss the fundamental principles of electronic cooling in mesoscopic superconducting hybrid structures, the related limitations and applications. We review recent work performed in Grenoble on the effects of Andreev reflection, photonic heat transport, phonon cooling, as well as on an innovative fabrication te...

  1. Street Cries and the urban refrain

    DEFF Research Database (Denmark)

    Kreutzfeldt, Jacob

    2012-01-01

    Street cries, though rarely heard in North European cities today, testify to ways in which audible practices shape and structure urban space. As paradigmatic for what Gilles Deleuze and Felix Guattari call the refrain, the ritualized and stylized practice of street cries may point at the dynamics...... the different methods employed in the two studies and presenting Deleuze and Guattaris theory about the refrain as a framework for further studies in the field, this article seeks to outline a fertile area of study for sound studies: the investigation of everyday refrains and the environmental relations...

  2. Street art, spaces and visual rhetoric

    Directory of Open Access Journals (Sweden)

    Marco Mondino

    2014-06-01

    Full Text Available Street-art is a widespread urban phenomenon characterised by several different styles and concepts. This essay will introduce few artistic works, analysing the rhetoric strategies used. Artists create unpredictable narratives catching the audiences’ attention through various regimes of visibility and some figures of speech, such as hyperbole, apostrophe, and camouflage. Therefore, the relationship between street artworks and the audience can trigger a discourse of challenge, conflict or complicity showed by the practice of rewriting or deleting of urban art that we will study.

  3. Street-Level Bureaucrats as Individual Policymakers:

    DEFF Research Database (Denmark)

    Baviskar, Siddhartha; Winter, Søren

    2016-01-01

    Lipsky (1980) pointed out that street-level bureaucrats (SLBs) are important policymakers due to the discretion they exercise and argued from a structural perspective that these workers manifest relatively similar coping behaviors owing to their shared working conditions, characterized by chronic......Lipsky (1980) pointed out that street-level bureaucrats (SLBs) are important policymakers due to the discretion they exercise and argued from a structural perspective that these workers manifest relatively similar coping behaviors owing to their shared working conditions, characterized...... and local political inefficacy, and their conceptual modification of job contents are all related to their use of coping....

  4. Four rules for taking your message to Wall Street.

    Science.gov (United States)

    Hutton, A

    2001-05-01

    Managers fail to communicate effectively with Wall Street for all sorts of reasons. But neglecting the investment community--particularly the analysts whose opinions shape the market and whose recommendations often make or break a company's share price--can knock the most carefully conceived and brilliantly executed strategy off course. The companies that struggle the most with providing good information to analysts are those in rapidly evolving industries, where the gap between traditional performance metrics and economic realities is at its widest. In these industries, a company's strategy and the variables that govern its performance can change radically in a short time. What's more, the metrics used to report performance often fail to capture the drivers of value in today's information economy. Few accounting measures are helpful when it comes to assessing the intangible assets--knowledge, skilled employees, and so forth--on which many of today's fastest-growing companies build their strategies. According to Amy Hutton, an associate professor at Harvard Business School, there are four basic rules for clear communications with Wall Street. First, make sure that your company's financial reporting reflects your strategy as closely as possible. Second, popularize the nonfinancial metrics that best predict--and flatter--the performance of your businesses. Third, appoint managers with recognized credibility to your strategic operations. Finally, cultivate the market experts who cover the industries in which you seek to compete. Hutton shows how AOL successfully followed these rules as it significantly changed its strategic direction and competitive arena.

  5. NASA Lewis Stirling SPRE testing and analysis with reduced number of cooler tubes

    Energy Technology Data Exchange (ETDEWEB)

    Wong, W.A.; Cairelli, J.E.; Swec, D.M.; Doeberling, T.J.; Lakatos, T.F. [National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center; Madi, F.J. [Sverdrup Technology, Inc., Cleveland, OH (United States). Lewis Research Center Group

    1994-09-01

    Free-piston Stirling power converters are a candidate for high capacity space power applications. The Space Power Research Engine (SPRE), a free-piston Stirling engine coupled with a linear alternator, is being tested at the NASA Lewis Research Center in support of the Civil Space Technology Initiative. The SPRE is used as a test bed for evaluating converter modifications which have the potential to improve converter performance and for validating computer code predictions. Reducing the number of cooler tubes on the SPRE has been identified as a modification with the potential to significantly improve power and efficiency. This paper describes experimental tests designed to investigate the effects of reducing the number of cooler tubes on converter power, efficiency and dynamics. Presented are test results from the converter operating with a reduced number of cooler tubes and comparisons between this data and both baseline test data and computer code predictions.

  6. NASA Lewis Stirling SPRE testing and analysis with reduced number of cooler tubes

    Science.gov (United States)

    Wong, Wayne A.; Cairelli, James E.; Swec, Diane M.; Doeberling, Thomas J.; Lakatos, Thomas F.; Madi, Frank J.

    1992-08-01

    Free-piston Stirling power converters are candidates for high capacity space power applications. The Space Power Research Engine (SPRE), a free-piston Stirling engine coupled with a linear alternator, is being tested at the NASA Lewis Research Center in support of the Civil Space Technology Initiative. The SPRE is used as a test bed for evaluating converter modifications which have the potential to improve the converter performance and for validating computer code predictions. Reducing the number of cooler tubes on the SPRE has been identified as a modification with the potential to significantly improve power and efficiency. Experimental tests designed to investigate the effects of reducing the number of cooler tubes on converter power, efficiency and dynamics are described. Presented are test results from the converter operating with a reduced number of cooler tubes and comparisons between this data and both baseline test data and computer code predictions.

  7. Performance Analysis of Joule-Thomson Cooler Supplied with Gas Mixtures

    Science.gov (United States)

    Piotrowska, A.; Chorowski, M.; Dorosz, P.

    2017-02-01

    Joule-Thomson (J-T) cryo-coolers working in closed cycles and supplied with gas mixtures are the subject of intensive research in different laboratories. The replacement of pure nitrogen by nitrogen-hydrocarbon mixtures allows to improve both thermodynamic parameters and economy of the refrigerators. It is possible to avoid high pressures in the heat exchanger and to use standard refrigeration compressor instead of gas bottles or high-pressure oil free compressor. Closed cycle and mixture filled Joule-Thomson cryogenic refrigerator providing 10-20 W of cooling power at temperature range 90-100 K has been designed and manufactured. Thermodynamic analysis including the optimization of the cryo-cooler mixture has been performed with ASPEN HYSYS software. The paper describes the design of the cryo-cooler and provides thermodynamic analysis of the system. The test results are presented and discussed.

  8. Study of thermal-flow processes in ash cooler cooperating with CFB boiler

    Directory of Open Access Journals (Sweden)

    Paweł Regucki

    2016-03-01

    Full Text Available The article presents an example of thermal-flow analysis of the bottom ash cooler cooperating with the circulating fluidized bed boiler. There is presented a mathematical model of series-parallel hydraulic system supplying the ash cooler in cooling water. The numerical calculations indicate an influence of changes of the pipeline geometrical parameters on the cooling water flow rate in the system. Paper discusses the methodology of the studies and presents examples of the results of thermal balance calculations based on the results of measurements. The numerical results of the thermal-flow analysis in comparison with the measurements on the object indicate that the presented approach could be used as a diagnostic tool investigating the technical state of the bottom ash cooler.

  9. Influence of the outlet air temperature on the thermohydraulic behaviour of air coolers

    Directory of Open Access Journals (Sweden)

    Đorđević Emila M.

    2003-01-01

    Full Text Available The determination of the optimal process conditions for the operation of air coolers demands a detailed analysis of their thermohydraulic behaviour on the one hand, and the estimation of the operating costs, on the other. One of the main parameters of the thermohydraulic behaviour of this type of equipment, is the outlet air temperature. The influence of the outlet air temperature on the performance of air coolers (heat transfer coefficient overall heat transfer coefficient, required surface area for heat transfer air-side pressure drop, fan power consumption and sound pressure level was investigated in this study. All the computations, using AirCooler software [1], were applied to cooling of the process fluid and the condensation of a multicomponent vapour mixture on two industrial devices of known geometries.

  10. Numerical simulation and optimization design of the EGR cooler in vehicle

    Institute of Scientific and Technical Information of China (English)

    Yu-qi HUANG; Xiao-li Yu; Guo-dong Lu

    2008-01-01

    The EGR(exhaust gas reeirculation)technique can greatly reduce the Nox emission of diesel engines,especially when an EGR cooler iS employed.Numerical simulations are applied to study the flow field and tempemture distributions inside the EGR cooler.Three different models of EGR cooler are investigated,among which model A is a traditional one,and models B and C are improved by adding a helical bafile in the cooling area.In models B and C the elltry directions of cooling water are different,which mostly influences the flow resistance.The results show that the improved structures not only lengthen the flow path of the cooling water,but also enhante the heat exchange rate between the cool and hot media.In conclusion we suggest that the improved Structures are more powerful than the traditional one.

  11. Physical Experiments to Investigate the Effects of Street Bottom Heating and Inflow Turbulence on Urban Street-Canyon Flow

    Institute of Scientific and Technical Information of China (English)

    Jae-Jin KIM; Jong-Jin BAIK

    2005-01-01

    The effects of street bottom heating and inflow turbulence on urban street-canyon flow are experimentally investigated using a circulating water channel. Three experiments are carried out for a street canyon with a street aspect ratio of 1. Results from each experiment with bottom heating or inflow turbulence are compared with those without bottom heating and appreciable inflow turbulence. It is demonstrated that street bottom heating or inflow turbulence increases the intensity of the canyon vortex. A possible explanation on how street bottom heating or inflow turbulence intensifies the canyon vortex is given from a fluid dynamical viewpoint.

  12. Development and Evaluation of a Sandia Cooler-based Refrigerator Condenser

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Terry A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kariya, Harumichi Arthur [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Leick, Michael T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Zimmerman, Mark D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Li, Manjie [Univ. of Maryland, College Park, MD (United States); Du, Yilin [Univ. of Maryland, College Park, MD (United States); Lee, Hoseong [Univ. of Maryland, College Park, MD (United States); Hwang, Yunho [Univ. of Maryland, College Park, MD (United States); Radermacher, Reinhard [Univ. of Maryland, College Park, MD (United States)

    2015-07-01

    This report describes the first design of a refrigerator condenser using the Sandia Cooler, i.e. air - bearing supported rotating heat - sink impeller. The project included ba seline performance testing of a residential refrigerator, analysis and design development of a Sandia Cooler condenser assembly including a spiral channel baseplate, and performance measurement and validation of this condenser system as incorporated into the residential refrigerator. Comparable performance was achieved in a 60% smaller volume package. The improved modeling parameters can now be used to guide more optimized designs and more accurately predict performance.

  13. A thermoacoustically driven cooler capable of reaching temperature below 77 K with no moving part

    Institute of Scientific and Technical Information of China (English)

    DAI Wei; LUO Ercang; LING Hong; HU Jianying

    2005-01-01

    @@ The pulse tube cooler has no cryogenic displacer and has attracted lots of attention in the field of cryocooler research. On the other hand, the thermoacoustic engine can generate self-oscillation and output work without moving components[1]. Combining both technologies leads to a cryogenic cooler system with no moving components at all, which has great advantages of high reliability, low manufacturing cost, etc. Limited by largest available pressure ratio of thermoacoustic engines, up to now the best results on such a combined system are 88.6K when standing-wave thermoacoustic engine[2] is used and 80.9K when traveling-wave thermoacoustic engine[3] is used.

  14. Experimental investigation of the influences of shape and surface area on the EGR cooler efficiency

    Science.gov (United States)

    Jang, Sanghoon; Park, Sangki; Choi, Kapseung; Kim, Hyungman

    2011-06-01

    The cooled EGR system is one of the most effective techniques currently available for reducing NOx emissions. In this study, engine dynamometer experiments were performed to investigate the efficiencies of the shell and tube-type and stack-type EGR coolers. The results show that the heat exchange of the stack-type EGR cooler is much more effective than that of the shell and tube type because of the increased surface area and better mixing of the coolant flow, and also more PM is produced at low exhaust gas temperature than at high temperature.

  15. Implementation Regimes and Street-Level Bureaucrats

    DEFF Research Database (Denmark)

    Winter, Søren; T. Dinesen, Peter; J. May, Peter

    -government regimes foster greater policy commitment, attention to rules, and adherence among frontline workers than is the case for a local-government implementation regime. These lead to actions of street-level bureaucrats in central-government regimes that are more in line with national policies than those...

  16. Strolling Along Barkor Street(Ⅰ)

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Barkor Street has witnessed enormous changes over the past few decades.But the Monument to theTang-Tubo Alliance,willow trees of the Tang Dynasty and large sutra pole, existing in front of JokhangMonastery, retains their original demeanor.

  17. [Agnosia for streets and defective root finding].

    Science.gov (United States)

    Takahashi, Nobuyoshi

    2011-08-01

    Topographical disorientation is identified as a condition in which patients are unable to find their way in familiar surroundings, such as their home neighborhood or the admitting hospital after the onset of illness. I proposed to classify topographical disorientation into two categories: agnosia for streets (landmark agnosia) and defective root finding (heading disorientation). Patients with agnosia for streets are unable to identify familiar buildings and landscapes. They can, however, morphologically perceive them and remember their way around familiar areas. The lesions are located in the right posterior part of the parahippocampus gyrus, anterior half of the lingual gyrus and adjacent fusiform gyrus. Clinical findings and functional imaging studies suggest that these regions play a crucial role in the interaction between the visual information of streets and memories of them, which are thought to be retained in the right anterior part of the temporal lobe. In particular, the posterior part of the parahippocampus gyrus is critical for the acquisition of novel information. On the other hand, patients with defective root finding can identify familiar streets, but cannot remember their own location or positional relation between two points within a comparatively wide range not surveyable at one time. The lesions are located in the right retrosplenial cortex (Areas 29, 30), posterior cingulate cortex (Areas 23, 31) and precuneus. Clinical findings and functional imaging studies suggest that these regions are involved in the orientation function for navigating in wide spaces. In particular, the retrosplenial cortex is critical for encoding novel information.

  18. Trauma among Street-Involved Youth

    Science.gov (United States)

    Bender, Kimberly A.; Thompson, Sanna J.; Ferguson, Kristin M.; Yoder, Jamie R.; Kern, Leah

    2014-01-01

    Previous research documents that street-involved youth experience rates of trauma and posttraumatic stress disorder (PTSD) that are significantly higher than their housed counterparts. Trauma and PTSD are of particular concern for homeless youth as they can negatively affect youths' ability to function adaptively and to transition off the…

  19. Vortex Cloud Street during AMTEX 75

    DEFF Research Database (Denmark)

    Jensen, Niels Otto; Agee, E. M.

    1978-01-01

    Strong northerly flow across Cheju Island, Korea, during the 1975 Air Mass Transformation Experiment (AMTEX 75) resulted in a pronounced vortex cloud street to the lee of the island on February 17 1975. This pattern has been studied and explained in terms of classical von Karman eddies shed...

  20. The Earl Lee Street Art Campaign

    Science.gov (United States)

    Bubba

    2013-01-01

    This article describes a catchy phrase with more to its meaning than first view. A slogan "All the girls love Earl Lee," appears in street art around the world. Earl Lee is a lovable, handsome man who owns the fictitious Earl Lube industries. Originally intended to bring a smile to people's faces at a time when there wasn't much to smile…

  1. Politicians, Managers, and Street-Level Bureaucrats

    DEFF Research Database (Denmark)

    May, Peter J.; Winter, Søren

    2010-01-01

    This article addresses the influence of politicians, managers, and the dispositions of street-level bureaucrats in shaping actions at the frontlines of policy implementation. We investigate these for the implementation of employment policy reforms in Denmark. Our findings show a large percentage ...

  2. Sesame Street Viewing Volunteer Training Manual.

    Science.gov (United States)

    Filep, Robert T.; And Others

    This guide was prepared to aid volunteers working with preschool children who view the television program, "Sesame Street". The suggestions in this booklet grew out of a study called the "Sesame Mother Pilot Project," conducted in 1970-71 by the Institute for Educational Development. This guide is divided into nine main parts:…

  3. Taking health promotion on to the streets.

    Science.gov (United States)

    Filgueiras, A

    1992-06-01

    In Brazil, until 1990, the authorities could legally arrest a child found alone in the streets, and put them in prison-like institutions. Their crime? To be poor, usually black and living on the streets. The Brazilian Center for the Defense of the Rights of Children and Adolescents (SOS Crianca) was set up a few years ago with the aim of changing this legislation. Together with other nongovernment organizations, SOS Crianca drew up new legislation, lobbied politicians and policymakers, and publicized the issue at a new Child and Adolescent Statute, based on the International Declaration of Children's Rights, was made law. Lawyers volunteered their services to SOS Crianca, making sure that young people had access to legal support, so that the new law could be put into practiced. AIDS has added to the difficulties of young people living on the streets. In 1988, using a strategy similar to the one above, SOS Crianca started to work with key organizations and the children themselves, to draw up an HIV prevention strategy for street children. As well as being threatened with violence and police arrest, these children lack a basic human right--access to health care. Public health services in Brazil do not reach the 40% of the population who live in absolute poverty, which includes young people on the streets. Preventing AIDS is seen by SOS Crianca to be just a part of promoting better health and providing overall healthcare. Educational activities will not work if children do not have access to treatment, or to basic needs like food and shelter. SOS Crianca does not employ doctors because it is not the role of nongovernment organizations to take over the state's responsibility to provide basic health care. But how can the public clinics, staffed with underpaid professionals and lacking basic equipment meet the needs of street children? Meetings were organized with different health professionals, involving those most sensitive to the problem in setting up a referral

  4. Food safety knowledge and practices of street foodvendors in Atbara ...

    African Journals Online (AJOL)

    Food safety knowledge and practices of street foodvendors in Atbara City (Naher Elneel State Sudan) ... African Journal of Biotechnology ... The study was conducted to evaluate the food safety knowledge and practices of street food vendors ...

  5. Microbiological assessment of ethnic street foods of the Himalayas

    Directory of Open Access Journals (Sweden)

    Niki Kharel

    2016-09-01

    Conclusion: The risks associated with street foods may be controlled by educating vendors about hygienic conditions. In conclusion, street foods are important ethnic foods sold in popular tourist spots in India for marginal local vendors.

  6. Microbiological Safety of Street Vended Foods in Jigjiga City ...

    African Journals Online (AJOL)

    GB

    RESULTS: The majority of the street food vendors were women, 120(90.9%), with the average age group of ... street food and fast foods are commonly consumed .... from each tube was seeded on appropriate media ... Time (h) Temperat ure.

  7. Street Littering in Nigerian Towns: towards a Framework for ...

    African Journals Online (AJOL)

    Nekky Umera

    riders, and all those practicing their trades along the streets. Respondents ... indicators (contents of our questionnaire) which helped to assess patterns of behaviour ... Litter levels were very high along the streets contiguous to very big markets.

  8. Reflective Teaching

    Science.gov (United States)

    Farrell, Thomas S. C.

    2013-01-01

    Thomas Farrell's "Reflective Teaching" outlines four principles that take teachers from just doing reflection to making it a way of being. Using the four principles, Reflective Practice Is Evidence Based, Reflective Practice Involves Dialogue, Reflective Practice Links Beliefs and Practices, and Reflective Practice Is a Way of Life,…

  9. Vulnerability to violence of girls of the street in Mauritania

    OpenAIRE

    Ballet, Jérôme; Sirven, N.; Bhukuth, A.; Rousseau, S.

    2011-01-01

    This article is concerned with an empirical study of girls of the street in Mauritania. This study is original for three main reasons. First, it investigates Mauritania, a country where there have been very few studies of the phenomenon of children of the street. Secondly, it seems to us that though the academic literature on street children sometimes provides comparisons between girls and boys, very few studies focus specifically on girls of the street. Thirdly, the literature focusing on ch...

  10. Off-street commercial sex : an exploratory study

    OpenAIRE

    O'Doherty, Tamara Carrine

    2007-01-01

    This thesis explores women’s experiences working in off-street prostitution venues in Vancouver, BC. The victimization experienced by street-based sex workers has led many people to conclude that prostitution is inherently dangerous. However, street-based workers form the minority of sex workers in Canada. The question remains, can their experiences be generalized to other types of prostitution? Consequently, this thesis examines whether female off-street sex workers face the same degree of v...

  11. POLICY EVALUATION OF RESTRUCTURING STREET VENDORS IN SURAKARTA CITY (Study of Street Vendors in Monument Park Banjarsari and Street Vendors in Manahan Stadium

    Directory of Open Access Journals (Sweden)

    Frahlevi Prajasari

    2015-08-01

    Full Text Available This study examined the policy evaluation of restructuring street vendors in Surakarta city. Street vendors represent the economic actors in the informal sector of urban economic activity. The government of City/District usually removes these street vendors by disguising this activity behind the reason of structuring, . The study used descriptive research with a qualitative approach. The relocation of street vendors in Surakarta City is orderly and smooth without violence which may impact badly on physic and material because the government of Surakarta City, especially Surakarta Mayor, uses persuasive approach. Notoharjo Market is a relocation place for street vendors at Banjarsari Monument Park. In the beginning, Notoharjo Market is crowded with buyers but current days, street vendors who occupy Notoharjo Market complain about lack of buyers. The lack of buyers at Notoharjo Market is because the facilities previously provided by the government of Surakarta City are not well maintained. The government of Surakarta City must listening all complains of street vendors for the smoothness and orderliness of trading activity of street vendors. Not only listening, but the government of Surakarta City also gives appropriate and best solution to street vendors such that street vendors feel comfort in selling and their income is better than before.

  12. An Art of Resistance: From the Street to the Classroom

    Science.gov (United States)

    Chung, Sheng Kuan

    2009-01-01

    Rooted in graffiti culture and its attitude toward the world, street art is regarded as a postgraffiti movement. Street art encompasses a wide array of media and techniques, such as traditional spray-painted tags, stickers, stencils, posters, photocopies, murals, paper cutouts, mosaics, street installations, performances, and video projections…

  13. Street language. A multilingual youth register in the Netherlands

    NARCIS (Netherlands)

    Schoonen, R.; Appel, R.

    2005-01-01

    This paper reports on an empirical study of street language, a multilingual youth register in the Netherlands. Nearly 300 secondary school students completed a questionnaire on their acquaintance with and use of street language. A subsample of students was also interviewed. Use of street language wi

  14. What Research Indicates about the Educational Effects of "Sesame Street."

    Science.gov (United States)

    Children's Television Workshop, New York, NY.

    This paper reviews the results of several studies that examined the educational effects of Sesame Street. Three studies by the Educational Testing Service on Sesame Street's first two seasons determined that among children who watched Sesame Street, those who watched the most scored highest on an achievement measure; frequent viewers made more…

  15. Optimization of the working fluid for a sorption-based Joule-Thomson cooler

    NARCIS (Netherlands)

    Wu, Y.; Zalewski, D.R.; Vermeer, C.H.; Brake, ter H.J.M.

    2013-01-01

    Sorption-based Joule–Thomson coolers operate vibration-free, have a potentially long life time, and cause no electromagnetic interference. Therefore, they are appealing to a wide variety of applications, such as cooling of low-noise amplifiers, superconducting electronics, and optical detectors. The

  16. Topology optimisation of passive coolers for light-emitting diode lamps

    DEFF Research Database (Denmark)

    Alexandersen, Joe

    2015-01-01

    This work applies topology optimisation to the design of passive coolers for light-emitting diode (LED) lamps. The heat sinks are cooled by the natural convection currents arising from the temperature difference between the LED lamp and the surrounding air. A large scale parallel computational...

  17. Development and Testing of an Integrated Sandia Cooler Thermoelectric Device (SCTD).

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Terry A.; Staats, Wayne Lawrence,; Leick, Michael Thomas; Zimmerman, Mark D.; Radermacher, Reinhard; Martin, Cara; Nasuta, Dennis; Kalinowski, Paul; Hoffman, William

    2014-12-01

    This report describes a FY14 effort to develop an integrated Sandia Cooler T hermoelectric D evice (SCTD) . The project included a review of feasible thermoelectric (TE) cooling applications, baseline performance testing of an existing TE device, analysis and design development of an integrated SCTD assembly, and performance measurement and validation of the integrated SCTD prototype.

  18. A separate two-stage pulse tube cooler working at liquid helium temperature

    Institute of Scientific and Technical Information of China (English)

    QIU Limin; HE Yonglin; GAN Zhihua; WAN Laihong; CHEN Guobang

    2005-01-01

    A novel 4 K separate two-stage pulse tube cooler (PTC) was designed and tested. The cooler consists of two separate pulse tube coolers, in which the cold end of the first stage regenerator is thermally connected with the middle part of the second regenerator. Compared to the traditional coupled multi-stage pulse tube cooler, the mutual interference between stages can be significantly eliminated. The lowest refrigeration temperature obtained at the first stage pulse tube was 13.8 K. This is a new record for single stage PTC. With two compressors and two rotary valves driving mode, the separate two-stage PTC obtained a refrigeration temperature of 2.5 K at the second stage. Cooling capacities of 508 mW at 4.2 K and 15 W at 37.5 K were achieved simultaneously. A one-compressor and one-rotary valve driving mode has been proposed to further simplify the structure of separate type PTC.

  19. AUTOMATIC CONTROL SYSTEM OF HEAT PUMP STATION GAS COOLER AT THE WIDE RANGE OF HEAT LOAD

    Directory of Open Access Journals (Sweden)

    Juravleov A.A.

    2008-08-01

    Full Text Available There is examined the structure the of control system of gas cooler of heat pump station, which uses the carbon dioxide as the working fluid in the transctitical thermodynamical cycle. It is analiyed the structure of the complex: heat pump station – district heating system.

  20. Long-life micro vacuum chamber for a micromachined cryogenic cooler

    NARCIS (Netherlands)

    Cao, H.; Vermeer, C.H.; Vanapalli, S.; Holland, H.J.; Brake, ter H.J.M.

    2015-01-01

    Micromachined cryogenic coolers can be used for cooling small electronic devices to improve their performance. However, for reaching cryogenic temperatures, they require a very good thermal insulation from the warm environment. This is established by a vacuum space that for adequate insulation has t

  1. Condensation-Fouling Interaction in Low-Temperature EGR-Coolers

    Directory of Open Access Journals (Sweden)

    Reißig Martin

    2014-01-01

    Full Text Available EGR cooling is a worthwhile technology capable of reducing NOx-emissions and increasing the efficiency of CI engines. Challenges arise when low-temperature cooling is applied with high fuel sulfur contents. The resulting sulfuric acid condenses in conjunction with the water of the exhaust gas and gives rise to corrosion of coolers and engine components. Additionally, fouling of the EGR cooler is exacerbated by the condensation of acidic components compromising EGR performance. In order to gain a better understanding of the underlying processes a combined experimental and model-based approach is presented. Tests of two different EGR-cooler concepts under various conditions showed a strong influence of the fuel sulfur content on fouling and condensation. The one-dimensional cooler model developed alongside these experiments consists of an activity coefficient model (NRTL of the binary system water - sulfuric acid and a condensation model that allows for simulating the coupled condensation of both vapor components. Comparison of experimental fouling and simulated condensation results show good agreement in interpreting critical fouling phenomena that occur at temperatures in between the acid-water dew point and the dew point of pure water.

  2. Improved Performance of an Indigenous Stirling Type Pulse Tube Cooler and Pressure Wave Generator

    Science.gov (United States)

    Kumar, J. Kranthi; Jacob, S.; Karunanithi, R.; Narasimham, G. S. V. L.; Damu, C.; Praveen, T.; Samir, M.

    Sustained efforts have been made in our laboratory to improve the performance of an indigenously developed pressure wave gen- erator by reducing the mechanical losses and the required input power. An acoustically matching pulse tube cooler, with a design target of 0.5 W at 80 K, was designed using Sage and experience gained from previous studies. The pulse tube cooler was fabri- cated and tested. The effect of regenerator stacking pattern on the cooler performance was studied by filling the regenerator with mesh of the same size #400 and with multi meshes #250, 325, 400. In present experiments, regenerator with #400 mesh at 30 bar filling pressure performed better with more energy efficiency. A no load temperature of 74 K was achieved with input power of 59 W corresponding to a cooling power of 0.22 W at 80 K. Parasitic heat load to the cooler was measured be 0.68 W. This heat load is primarily by heat conduction through the regenerator and pulse tube wall. By reducing the wall thickness from 0.30 mm to 0.15 mm, the parasitic loads can be reduced by 50%.

  3. Bacteriological Quality of Water Cooler Dispensers of Educational Settings in Zanjan University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    Hassan Hassanzadazar

    2017-03-01

    Full Text Available Background: Safe drinking water is one of the main factors in improving health status of the population. The aim of this study was assessment of the microbiological quality, determination of pH and residual chlorine in water coolers’ drinking water in educational centers of Zanjan University of medical Sciences in 2015 and comparing the results with the Iranian national standards. Methods: In this cross-sectional study, water samples of all used water cooler apparatuses were sampled and transferred rapidly to the laboratory. pH and residual free chlorine were measured by pH meter and Chlorine Residual Testing kit, respectively. Total coliforms, Escherichia coli, Mold and yeasts count were enumerated according to the Iranian national standards No. 1011, 3759, 5271 and 10899-1, respectively. Data were analyzed through the statistical soft wares. Results: The obtained results indicated that 44.44% of the samples were non-standard because of low residual chlorine. 44.44% and 27.8% of the taken water samples of water cooler dispensers were contaminated with mold or yeast and Escherichia coli, respectively. Conclusion: According to some microbial contamination in water samples of water cooler devices to ensure availability clean water to consumers (students and hospital’s visitors continuous monitoring, proper maintenance and regular inspection of the water cooler dispensers seems necessary.

  4. Air cooler ducts. A simple kind of air conditioner; Luftkuehlschaechte. Eine einfache Teilklimaanlage

    Energy Technology Data Exchange (ETDEWEB)

    Glueck, B. [F und E TGA, Joessnitz (Germany); Westsaechsische Hochschule Zwickau (F.H.) (Germany)

    2005-07-01

    Air cooler duct cabinets are used increasingly for cooling and demoisturizing of room air and fresh air, sometimes also as auxiliary heating systems. They are more complex than conventional and have specific characteristics concerning construction, dimensioning, optimisation and control. A newly developed computer program enables pre-assessment of specific operational situations. (orig.)

  5. 50 mK cooling solution with an ADR precooled by a sorption cooler

    Science.gov (United States)

    Luchier, N.; Duval, J. M.; Duband, L.; Camus, P.; Donnier-Valentin, G.; Linder, M.

    2010-09-01

    CEA/SBT is currently developing a 2.5 K-50 mK cooling solution composed of a small demagnetization refrigerator (ADR) precooled by a sorption cooler, equivalent to the high temperature stage of a two-stage ADR system. Thanks to the use of this dual technology, a low weight cooler able to reach 50 mK with a heat sink up to 2.5 K can be designed. Because the sorption cooler is probably the lightest solution to produce sub-Kelvin temperatures, these developments allow us to propose a solution to face the drastic reduction in the mass budget of space missions like SPICA or IXO. The European Space Agency (ESA) is funding the development of an engineering model able to produce 1 μW net heat lift at 50 mK. It is sized so that the sorption cooler provides an additional 10 μW at 300 mK. The ESA main requirements are an autonomy of more than 24 h and a recycling time smaller than 8 h. We present the design of the system able to meet these requirements as well as the expected performances and preliminary measurements.

  6. 76 FR 31795 - Energy Conservation Program: Energy Conservation Standards for Walk-In Coolers and Freezers...

    Science.gov (United States)

    2011-06-02

    ... Part 431 RIN 1904-AB85 Energy Conservation Program: Energy Conservation Standards for Walk-In Coolers... . SUPPLEMENTARY INFORMATION: I. Background The Energy Policy and Conservation Act (EPCA), as amended by section... Subjects in 10 CFR Part 431 Administrative practice and procedure, Energy conservation, Reporting...

  7. Long-life micro vacuum chamber for a micromachined cryogenic cooler

    NARCIS (Netherlands)

    Cao, Haishan; Vermeer, Cristian Hendrik; Vanapalli, Srinivas; Holland, Herman J.; ter Brake, Hermanus J.M.

    2015-01-01

    Micromachined cryogenic coolers can be used for cooling small electronic devices to improve their performance. However, for reaching cryogenic temperatures, they require a very good thermal insulation from the warm environment. This is established by a vacuum space that for adequate insulation has

  8. Low specimen drift holder, cooler and heat flow reductor for use in microscopy

    NARCIS (Netherlands)

    Zandbergen, H.W.

    2015-01-01

    The present invention is in the field of a low specimen drift holder and cooler for use in microscopy, and a microscope comprising said holder. The present invention is in the field of microscopy, specifically in the field of electron and focused ion beam mi- croscopy (EM and FIB). However it applic

  9. Split Stirling linear cryogenic cooler for a new generation of high temperature infrared imagers

    Science.gov (United States)

    Veprik, A.; Zechtzer, S.; Pundak, N.

    2010-04-01

    Split linear cryocoolers find use in a variety of infrared equipment installed in airborne, heliborne, marine and vehicular platforms along with hand held and ground fixed applications. An upcoming generation of portable, high-definition night vision imagers will rely on the high-temperature infrared detectors, operating at elevated temperatures, ranging from 95K to 200K, while being able to show the performance indices comparable with these of their traditional 77K competitors. Recent technological advances in industrial development of such high-temperature detectors initialized attempts for developing compact split Stirling linear cryogenic coolers. Their known advantages, as compared to the rotary integral coolers, are superior flexibility in the system packaging, constant and relatively high driving frequency, lower wideband vibration export, unsurpassed reliability and aural stealth. Unfortunately, such off-the-shelf available linear cryogenic coolers still cannot compete with rotary integral rivals in terms of size, weight and power consumption. Ricor developed the smallest in the range, 1W@95K, linear split Stirling cryogenic cooler for demanding infrared applications, where power consumption, compactness, vibration, aural noise and ownership costs are of concern.

  10. Mechanical cooler system for the next-generation infrared space telescope SPICA

    Science.gov (United States)

    Shinozaki, Keisuke; Ogawa, Hiroyuki; Nakagawa, Takao; Sato, Yoichi; Sugita, Hiroyuki; Yamawaki, Toshihiko; Mizutani, Tadahito; Matsuhara, Hideo; Kawada, Mitsunobu; Okabayashi, Akinobu; Tsunematsu, Shoji; Narasaki, Katsuhiro; Shibai, Hiroshi

    2016-07-01

    The Space Infrared Telescope for Cosmology and Astrophysics (SPICA) is a pre-project of JAXA in collaboration with ESA to be launched in the 2020s. The SPICA mission is to be launched into a halo orbit around the second Lagrangian point in the Sun-Earth system, which allows us to use effective radiant cooling in combination with a mechanical cooling system in order to cool a 2.5m-class large IR telescope below 8K. Recently, a new system design in particular thermal structure of the payload module has been studied by considering the technical feasibility of a cryogenic cooled telescope within current constraints of the mission in the CDF (Concurrent Design Facility) study of ESA/ESTEC. Then, the thermal design of the mechanical cooler system, for which the Japanese side is responsible, has been examined based on the CDF study and the feasible solution giving a proper margin has been obtained. As a baseline, 4K / 1K-class Joule-Thomson coolers are used to cool the telescope and thermal interface for Focal Plane Instruments (FPIs). Additionally, two sets of double stirling coolers (2STs) are used to cool the Telescope shield. In this design, nominal operation of FPIs can be kept when one mechanical cooler is in failure.

  11. The "ICE" study: feasibility of inexpensive commercial coolers on mobile EMS units.

    Science.gov (United States)

    Kane, Kathleen E; Tomsho, Robert J; Pheasant, Karen; Stauffer, Thomas; Schoenfeldt, Brent; Hamilton, Scott; Kain, Travis; Kane, Bryan G

    2014-06-01

    Prehospital postresuscitation induced hypothermia (IH) has been shown to reduce neurological complications in comatose cardiac-arrest survivors. Retrofitting ambulances to include equipment appropriate to initiate hypothermia, such as refrigeration units for cooled saline, is expensive. The objective of this nonhuman subject research study was to determine if inexpensive, commercially available coolers could, in conjunction with five reusable ice packs, keep two 1 L bags of precooled 0.9% normal saline solution (NSS) at or below 4°C for an average shift of eight to 12 hours in a real-world environment, on board in-service Emergency Medical Service (EMS) units, over varying weather conditions in all seasons. The coolers were chosen based on availability and affordability from two nationally available brands: The Igloo MaxxCold (Igloo Products Corp., Katy, Texas USA) and Coleman (The Coleman Company, Wichita, Kansas USA). Both are 8.5 liter (nine-quart) coolers that were chosen because they adequately held two 1 L bags of saline solution, along with the reusable ice packs designated in the study design, and were small enough for ease of placement on ambulances. Initial testing of the coolers was conducted in a controlled environment. Thereafter, each EMS unit was responsible to cool the saline to less than 4°C prior to shift. Data were collected by emergency medical technicians, paramedics, and resident physicians working in seven different ambulance squads. Data analysis was performed using repeated measurements recorded over a 12-hour period from 19 individual coolers and were summarized by individual time points using descriptive statistics. Initial testing determined that the coolers maintained temperatures of 4°C for 12 hours in a controlled environment. On the ambulances, results based on the repeated measurements over time revealed that the saline solution samples as defined in the protocol, remained consistently below 4°C for 12 hours. Utilizing the lower

  12. Lead concentrations and isotope ratios in street dust determined by electrothermal atomic absorption spectrometry and inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Nageotte, S M; Day, J P

    1998-01-01

    A major source of environmental lead, particularly in urban areas, has been from the combustion of leaded petrol. Street dust has previously been used to assess urban lead contamination, and the dust itself can also be a potential source of lead ingestion, particularly to children. The progressive reduction of lead in petrol, in recent years, would be expected to have been reflected in a reduction of lead in urban dust. We have tested this hypothesis by repeating an earlier survey of Manchester street dust and carrying out a comparable survey in Paris. Samples were collected from streets and parks, lead was extracted by digestion with concentrated nitric acid and determined by electrothermal atomic absorption spectrometry. Lead isotope ratios were measured by inductively coupled plasma mass spectrometry. Results for Manchester show that lead concentrations have fallen by about 40% (street dust averages, 941 micrograms g-1 (ppm) in 1975 down to 569 ppm in 1997). In Paris, the lead levels in street dust are much higher and significant differences were observed between types of street (not seen in Manchester). Additionally, lead levels in parks were much lower than in Manchester. Samples collected under the Eiffel Tower had very high concentrations and lead isotope ratios showed that this was unlikely to be fallout from motor vehicles but could be due to the paint used on the tower. Isotope ratios measurements also revealed that lead additives used in France and the UK come from different sources.

  13. Low vibration microminiature split Stirling cryogenic cooler for infrared aerospace applications

    Science.gov (United States)

    Veprik, A.; Zechtzer, S.; Pundak, N.; Kirkconnel, C.; Freeman, J.; Riabzev, S.

    2011-06-01

    The operation of the thermo-mechanical unit of a cryogenic cooler may originate a resonant excitation of the spacecraft frame, optical bench or components of the optical train. This may result in degraded functionality of the inherently vibration sensitive space-borne infrared imager directly associated with the cooler or neighboring instrumentation typically requiring a quiet micro-g environment. The best practice for controlling cooler induced vibration relies on the principle of active momentum cancellation. In particular, the pressure wave generator typically contains two oppositely actuated piston compressors, while the single piston expander is counterbalanced by an auxiliary active counter-balancer. Active vibration cancellation is supervised by a dedicated DSP feed-forward controller, where the error signals are delivered by the vibration sensors (accelerometers or load cells). This can result in oversized, overweight and overpriced cryogenic coolers with degraded electromechanical performance and impaired reliability. The authors are advocating a reliable, compact, cost and power saving approach capitalizing on the combined application of a passive tuned dynamic absorber and a low frequency vibration isolator. This concept appears to be especially suitable for low budget missions involving mini and micro satellites, where price, size, weight and power consumption are of concern. The authors reveal the results of theoretical study and experimentation on the attainable performance using a fullscale technology demonstrator relying on a Ricor model K527 tactical split Stirling cryogenic cooler. The theoretical predictions are in fair agreement with the experimental data. From experimentation, the residual vibration export is quite suitable for demanding wide range of aerospace applications. The authors give practical recommendations on heatsinking and further maximizing performance.

  14. Strategies to ensure the welfare of street children

    Directory of Open Access Journals (Sweden)

    Saurabh RamBihariLal Shrivastava

    2015-01-01

    Full Text Available Street children refer to a vulnerable section of children who lives on the street in the absence of any guidance of a responsible person, to ensure their own or their family′s survival. Multiple determinants have been ascertained in the causation of the menace of street children. In order to address the challenges faced by street children, there is an indispensable need to develop a comprehensive strategy by involving all the concerned stakeholders. To conclude, to counter the menace of street children, there is a definite need to understand the role of heterogeneous determinants that push children towards street life, so that the welfare needs of street children can be safeguarded and the problem can be addressed at the grass root level.

  15. Self-Localization at Street Intersections.

    Science.gov (United States)

    Fusco, Giovanni; Shen, Huiying; Coughlan, James M

    2014-05-01

    There is growing interest among smartphone users in the ability to determine their precise location in their environment for a variety of applications related to wayfinding, travel and shopping. While GPS provides valuable self-localization estimates, its accuracy is limited to approximately 10 meters in most urban locations. This paper focuses on the self-localization needs of blind or visually impaired travelers, who are faced with the challenge of negotiating street intersections. These travelers need more precise self-localization to help them align themselves properly to crosswalks, signal lights and other features such as walk light pushbuttons. We demonstrate a novel computer vision-based localization approach that is tailored to the street intersection domain. Unlike most work on computer vision-based localization techniques, which typically assume the presence of detailed, high-quality 3D models of urban environments, our technique harnesses the availability of simple, ubiquitous satellite imagery (e.g., Google Maps) to create simple maps of each intersection. Not only does this technique scale naturally to the great majority of street intersections in urban areas, but it has the added advantage of incorporating the specific metric information that blind or visually impaired travelers need, namely, the locations of intersection features such as crosswalks. Key to our approach is the integration of IMU (inertial measurement unit) information with geometric information obtained from image panorama stitchings. Finally, we evaluate the localization performance of our algorithm on a dataset of intersection panoramas, demonstrating the feasibility of our approach.

  16. The use of photography as emancipatory action: an experience report with people in street situation

    Directory of Open Access Journals (Sweden)

    Juliana de Oliveira Perez

    2014-08-01

    Full Text Available This study aims to present a reflection on the experience of the use of photography by the occupational therapist with the people living in the streets of a Specialized Reference Center for Social Assistance to People in Street Situation - CREAS-POP of a municipality in Sao Paulo state, Brazil. The Photography Workshop aimed to provide an insertion and a different relationship with the urban space and population to the person living in the streets. Participants were asked to photograph something that arouses their interest in urban spaces. The photograph gave them a different view of themselves, allowing them to perceive themselves as subjects with rights and social actors, and not as an object of societal observation. Perceiving themselves as citizens, they came out of invisibility, and an improvement in self-esteem and greater engagement in the activities proposed was observed. The workshop also resulted in a photo exhibit open to the public that aimed to interfere with pre-conceptions and prejudices that society has built about people in street situation and give visibility to the creative potential of this population.

  17. Cooler Rings and their Applications - Proceedings of the 19th Ins Symposium

    Science.gov (United States)

    Katayama, T.; Noda, A.

    1991-08-01

    The Table of Contents for the full book PDF is as follows: * Organizing Committee * Preface * Opening Address * I. STATUS REPORT * I-1 The IUCF Cooler after Three Years * I-2 The Heidelberg Heavy Ion Cooler Ring TSR * I-3 Storage and Cooling of Heavy Ions in the ESR up to 200 MeV/u * I-4 Present Status of CELSIUS * I-5 Cooler Synchrotron TARN II, Present and Future * I-6 SATURNE II and MIMAS Status Report * I-7 CRYRING - a Low Energy Heavy Ion Facility * I-8 The Ukrainian (INR, Kiev's) Storage Ring * I-9 Status of the COSY-Jülich Project * II. BEAM COOLING * II-1 In Memory of Dr. Helmut Poth * II-2 Performance of the IUCF Electron Cooling System * II-3 Electron Cooling at TARN II * II-4 Status of the ESR-Electron Cooler and First Results * II-5 Physics with Stored Lithium Ions: Intrabeam Relaxation, Laser Cooling, and Observation of a Cold and Long Lived Ion Beam * II-6 Laser Cooling and Beam Crystallization * II-7 Cyclotron Maser Cooling of Electron and Ion Beams * III. ION TRAP * III-1 Penning Trap Experiments at the University of Washington and at NIST in Boulder * III-2 The HITRAP Project at GSI * III-3 Electron Cooling of Trapped Antiprotons * III-4 Some Results of an RF Ion Trap at NRLM * III-5 Preliminary Results of Laser Cooling of Stored Be Ions in a Penning Trap * III-6 Construction of an RF Ion-Trap for Nuclear Laser Spectroscopy * IV. NUCLEAR AND PARTICLE PHYSICS * IV-1 High-Resolution Spectroscopy of Deeply-Bound Pionic Atoms in Heavy Nuclei by Pion-Transfer Reactions of Inverse Kinematics Using the GSI Cooler Ring ESR * IV-2 Study of Exotic Nuclei Using a Storage Ring * IV-3 Nuclear Physics with the Indiana Cooler * IV-4 The Anomalous Magnetic Moment of the Muon * IV-5 Particle Physics at CELSIUS * IV-6 ϕ0-Factory using TARN II Accelerator * IV-7 Measurement of Energy Dependent Phenomena with Intenal (Polarized) Targets in TARN II * V. ACCELERATOR * V-1 Advanced Stacking Methods Using Electron Cooling at the TSR Heidelberg * V-2 Ultra High Vacuum

  18. Influence of using plural household air coolers on the air cooling demand. Actual state survey of air coolers in use. Kateiyo eakon no fukusu hoyuka ga reibo juyo ni oyobosu eikyo. Eakon shiyo jittai chosa kara

    Energy Technology Data Exchange (ETDEWEB)

    Higashida, R. (The Institute of Energy Economics, Tokyo (Japan))

    1994-07-01

    The present rise in power peak is judged mainly attributable to the increase in household and business use energy demand particularly for air cooling. In the present investigation, the actual state of air coolers domestically used was surveyed in the afternoon (from 1200 to 1600 hours) during the last ten days of August, which survey was followed by a study of relation between the number of air coolers domestically installed and used, and their operational state. Explanation is made of the present status of household air cooling demand, questionnaire survey and sampling, actual state analysis of air coolers in use, and the trend of household air cooling demand. As a result of the survey, about 10% of the homes use simultaneously plural units of air cooler in the afternoon, while about 50% do only one unit. With an increase in number of air coolers installed, their operation rate rises. It is concluded that the room-by-room trend and potentiality of air coolers will depend upon the operation rate of household air coolers. In the long tern outlook, it is indispensable to uninterruptedly watch the future change in power peak due to that in life style such as the family composition and home structure in the society with ages advanced. 18 figs., 9 tabs.

  19. Thermal Assessment of Landsat-7 ETM+ Radiative Cooler in Instrument and Spacecraft Thermal Vacuum Tests and in Flight

    Science.gov (United States)

    Choi, Michael K.

    1999-01-01

    During the radiative cooler cool-down phase of the Landsat-7 Enhanced Thematic Mapper Plus (ETM+) instrument thermal vacuum test #3, the coldest temperature that the Cold Focal Plane Array (CFPA) achieved was 89.5 K. The cold stage/CFPA temperature decreased from 315 K to 89.5 K in 80 hours. In the spacecraft and instrument integrated thermal vacuum test, the cold stage/CFPA temperature decreased from 315 K to 86.9 K in 80 hours, and was still decreasing at a rate of 0.08 K/hr when the cool-down was terminated. The cool-down was faster, and a colder CFPA temperature was obtained. In flight, the cooler cool- down was even faster, and colder. The cold stage/CFPA temperature decreased from 315 K to 89.7 K in 33 hours, and was still decreasing at a rate of 1 K/hr when cool- down was terminated at 89.7 K. The factors that affected the ETM+ cooler cool-down are the radiation heat sink temperature for the cold stage and intermediate stage, parasitic radiation heat load to the cooler, parasitic conduction heat load to the cooler, and cooler outgas time preceding cooler cool-down.

  20. Thermal Assessment of Landsat-7 ETM+ Radiative Cooler in Instrument and Spacecraft Thermal Vacuum Tests and in Flight

    Science.gov (United States)

    Choi, Michael K.

    1999-01-01

    During the radiative cooler cool-down phase of the Landsat-7 Enhanced Thematic Mapper Plus (ETM+) instrument thermal vacuum test #3, the coldest temperature that the Cold Focal Plane Array (CFPA) achieved was 89.5 K. The cold stage/CFPA temperature decreased from 315 K to 89.5 K in 80 hours. In the spacecraft and instrument integrated thermal vacuum test, the cold stage/CFPA temperature decreased from 315 K to 86.9 K in 80 hours, and was still decreasing at a rate of 0.08 K/hr when the cool-down was terminated. The cool-down was faster, and a colder CFPA temperature was obtained. In flight, the cooler cool- down was even faster, and colder. The cold stage/CFPA temperature decreased from 315 K to 89.7 K in 33 hours, and was still decreasing at a rate of 1 K/hr when cool- down was terminated at 89.7 K. The factors that affected the ETM+ cooler cool-down are the radiation heat sink temperature for the cold stage and intermediate stage, parasitic radiation heat load to the cooler, parasitic conduction heat load to the cooler, and cooler outgas time preceding cooler cool-down.

  1. Household and family characteristics of street children in Aracaju, Brazil.

    Science.gov (United States)

    Abdelgalil, S; Gurgel, R G; Theobald, S; Cuevas, L E

    2004-09-01

    To describe the family background of street children in Aracaju, Brazil, their parents' perception of street life, and the reasons for the high prevalence of males observed among street children. Cross sectional study using semi-structured interviews and qualitative focus group discussions with parents of purposively selected index street children. Fifty eight families were enrolled. Most participants were single parent, female headed families living in slums or low cost housing, with high levels of illiteracy, drug use, unemployment, and a history of migration. Most parents reported receiving financial support from their children and were aware of the dangers of the street. Many parents had lived in the street, worked from an early age, and had been adolescent parents themselves. Parents perceived that the street was more dangerous for girls than for boys. Besides economic reasons, parents highlighted the role of peers and drug use in pulling their children to the street. A total of 187 siblings were identified. Siblings had poor school performance with high school drop out rates. Twenty per cent of the adolescent girl siblings were not living at home. Gender determined the type of work undertaken by children and adolescents. Males worked in the streets and females worked as housemaids, shop assistants, and in restaurants and bars. Family disintegration, poverty, drug use, adolescent pregnancy, peer pressure, and socially constructed gender roles determine the characteristics of children in the street. There is an urgent need for increased social support in this area.

  2. 蛇管与夹套冷却CSTR温度双重控制%Temperature dual control of CSTR with coil cooler and jacket cooler

    Institute of Scientific and Technical Information of China (English)

    王再英; 王正宇

    2012-01-01

    The CSTR is important chemical industrys. The temperature dual temperature control system solution is proposed for CSTR with coil cooling and jacket cooling after researching the insufficiency the single loop control using only one manipulating variable and to be incapable satisfy the dynamic and static performance simultaneity. Under the dual control system, the coil cooler eliminates quickly the error and the temperature returns to set value as soon as the CSTR temperature error appear, then the coil cooler load variety for the CSTR cooling is replaced gradually by the more efficient jacket cooler, namely, CSTR temperature is controlled by the manipulating variable possessing finer dynamic property (coil cooler) in dynamic process, transition shorter and dynamic error smaller; and in the stable process, the main cooling load in the CSTR is shouldered by the jacket cooler, more cooling efficient and lower consumption of cooling water. The dual control solution takes advantage of coil cooling and jacket cooling respectively, so that both dynamic and static characteristic of the CSTR temperature control get more ideal. Finally, the advantage of the CSTR temperature dual control is verified for control precision and dynamic response, and energy-saving and consumption reducing by the semi-physical simulation. The dual control systems solution can also be applied to other production equipment or system with the similar structure features.%连续搅拌釜式化学反应器(CSTR)是重要的化工设备.对蛇管与夹套双冷却CSTR单回路温度控制方案只利用一种操纵变量,无法兼顾动态性能与静态性能的不足进行了深入分析后,提出了CSTR温度双重控制系统方案.通过双重系统的协调控制,在温度出现偏差时由蛇管冷却器快速消除温度偏差,使温度迅速返回设定值;然后由冷却效率高的夹套冷却器逐步取代蛇管冷却器所承担的冷却负荷变化——即在动态过程,由动态性

  3. Design instructions for condensers and recirculation coolers with axial blowers; Auslegungshinweis fuer Verfluessiger und Rueckkuehler mit Axialventilatoren

    Energy Technology Data Exchange (ETDEWEB)

    Handschuh, R. [Hans Guentner GmbH, Fuerstenfeldbruck (Germany)

    2003-07-01

    Apart from an explanation of the selectrion criteria for condensers and recirculation coolers with axial blowers for outside installation, information is presented on sound propagation. Selection according to the condensing capacity O{sub c}, the recooling rate Q{sub H} and the available floor space can be made with the aid of the Guentner Product Calculator GPC. Permissible noise emissions and adjacent installation of condensers and recoolers are gone into as well as noise propagation as a function of external noise, noise direction, noise reflection, the number of noise sources, the distance of the noise source from the emission point, and possible noise abatement factors are gone into as well. (orig.) [German] Neben der Erlaeuterung der Auswahlkriterien fuer Verfluessiger und Rueckkuehler mit Axialventilatoren zur Aufstellung im Freien werden Hinweise fuer die Schallausbreitung gegeben. Die Auswahl nach der Verfluessigungsleistung Q{sub c} bzw. der Rueckkuehlleistung Q{sub H} und der vorhandenen Aufstellflaeche kann mit dem Guentner Product Calculator GPC geschehen. Es wird auf die zulaessige Geraeuschimmission auf die Nachbarschaft von Verfluessigern und Rueckkuehlern eingegangen und deren Schallausbreitung in Abhaengigkeit von Fremdgeraeuscheinwirkungen, Schallrichtwirkung, der Schallreflexion, der Anzahl der Schallquellen, der Entfernung der Schallquelle zur Emissionsstelle und moegliche Daempfungen betrachtet. (orig.)

  4. Numerical analysis of thermal effects in semiconductor disk laser with TEC cooler

    Science.gov (United States)

    Zhu, Renjiang; Zhang, Peng; Jiang, Maohua

    2016-11-01

    Based on generalized heat transfer model of thermoelectric cooler(TEC), the heat management model of semiconductor disk laser with TEC cooler has been built. With finite element method, this article has calculated the temperature distribution characteristics, and studied the effects of TEC current, heat exchange coefficient, the heatsink and the pump laser for the maximum temperature of quantum wells. Calculations show that the heat transfer coefficient significantly affects the ability of the TEC temperature shift, cooling system performance which is nearly inversely proportional to the heatsink thermal conductivity is not sensitive to its the thickness variation, and the performance of oxygen-free copper with optimization of the area is close to diamond. Meanwhile the maximum temperature of the quantum well has a linear relationship with the pump power, and increasing the pump spot size is an effective way to increase the optical power output

  5. Pulse tube cooler having 1/4 wavelength resonator tube instead of reservoir

    Science.gov (United States)

    Gedeon, David R. (Inventor)

    2008-01-01

    An improved pulse tube cooler having a resonator tube connected in place of a compliance volume or reservoir. The resonator tube has a length substantially equal to an integer multiple of 1/4 wavelength of an acoustic wave in the working gas within the resonator tube at its operating frequency, temperature and pressure. Preferably, the resonator tube is formed integrally with the inertance tube as a single, integral tube with a length approximately 1/2 of that wavelength. Also preferably, the integral tube is spaced outwardly from and coiled around the connection of the regenerator to the pulse tube at a cold region of the cooler and the turns of the coil are thermally bonded together to improve heat conduction through the coil.

  6. RFQ beam cooler and buncher for collinear laser spectroscopy of rare isotopes

    Science.gov (United States)

    Barquest, B. R.; Bollen, G.; Mantica, P. F.; Minamisono, K.; Ringle, R.; Schwarz, S.; Sumithrarachchi, C. S.

    2017-09-01

    A radiofrequency quadrupole (RFQ) ion beam cooler and buncher has been developed to deliver bunched beams with low transverse emittance, energy spread, and time spread to the BECOLA collinear laser spectroscopy system at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University. The beam cooler and buncher contains new features which enhance performance, especially for high count rate beams, as well as simplifying construction, maintenance, and operation. The transverse emittance, energy spread, and time spread of the bunched beam, as well as buncher efficiency are reported, showcasing the capabilities of the BECOLA facility to perform collinear laser spectroscopy measurements with bunched rare isotope beams at NSCL and at the future Facility for Rare Isotope Beams (FRIB).

  7. Parametric System Identification of Thermoelectric Cooler for Single Photon Avalanche Diode Application

    Directory of Open Access Journals (Sweden)

    Nurul Izzati Samsuddin

    2013-06-01

    Full Text Available The purpose of this study is to model the Thermoelectric Coolers (TEC by means of computational intelligence system identification. Thermoelectric coolers are widely used in cooling, maintaining and stabilizing the temperature of the Single Photon Avalanche Diode (SPAD. SPAD is a temperature sensitive optoelectronic device, where even a slight variation in temperature can cause unstable performance in quantum efficiency, responsibility and dark counts. However, it is not a simple task to derive a mathematical model for TEC since it varies with the operating condition. In this study, Particle Swarm Optimization (PSO was used to identify the mathematical model of the multistage TEC (1639733 from Element 14, which encapsulates dynamics of the SPAD, heat sink and components of the cooling heat exchanger. The model was validated by correlation tests, percentage accuracy and also by comparing its time and frequency responses against that of the TEC. It was found that the obtained model has a good representation of the actual system.

  8. Heat Transfer Research of Gas-solid-liquid Three Phase Coupling of EGR Cooler

    Directory of Open Access Journals (Sweden)

    Fu-Wu Yan

    2014-05-01

    Full Text Available The main aim of the study is to get the temperature and backpressure of a car engine exhaust gas which goes through the EGR-cooler. So the internal fluid flow and heat transfer process of the EGR cooler must be studied more clearly, numerical simulations are applied. Based on the strong coupling method, gas-solid-liquid three phases coupling model of the typical heat transfer unit is established. According to the coupling result, the heat flux of the tube’s outside surface is gained and then mapped to the inner surface of the cooler’s water. The water model is set up based on the separation coupling method. According to the analysis of the calculation, the detailed pressure and temperature distribution of the gas, water and solid are obtained. From the distribution cloud, we know the changes of the parameters along the fluid flows streamline.

  9. Comparison of Test Stand and Helicopter Oil Cooler Bearing Condition Indicators

    Science.gov (United States)

    Dempsey, Paula J.; Branning, Jeremy; Wade, Damiel R.; Bolander, Nathan

    2010-01-01

    The focus of this paper was to compare the performance of HUMS condition indicators (CI) when detecting a bearing fault in a test stand or on a helicopter. This study compared data from two sources: first, CI data collected from accelerometers installed on two UH-60 Black Hawk helicopters when oil cooler bearing faults occurred, along with data from helicopters with no bearing faults; and second, CI data that was collected from ten cooler bearings, healthy and faulted, that were removed from fielded helicopters and installed in a test stand. A method using Receiver Operating Characteristic (ROC) curves to compare CI performance was demonstrated. Results indicated the bearing energy CI responded differently for the helicopter and the test stand. Future research is required if test stand data is to be used validate condition indicator performance on a helicopter.

  10. Optimization of a Localized Air Conditioning System Using Thermoelectric Coolers for Commercial Vehicles

    Science.gov (United States)

    Wan, Qiushi; Deng, Yadong; Su, Chuqi; Wang, Yiping

    2016-11-01

    To improve the thermal comfort and energy saving of commercial vehicles, an auxiliary air conditioning (AC) system has been constructed. Several distributed components using thermoelectric coolers were applied in a localized AC system to adjust the microclimate around the driver only. A computational fluid dynamics model of a commercial vehicle cabin with a driver was built, the temperature field of the cabin investigated, and the thermal comfort analyzed. Based on the results of the simulations, the temperature around the cold side of the thermoelectric coolers is discussed and optimized by means of the response surface methodology and a multiobjective genetic algorithm. To validate the simulation and optimization results, a bench test was carried out; the results obtained from the simulation showed good agreement with the experimental results.

  11. Indirect evaporative cooler using membrane-contained, liquid desiccant for dehumidification

    Energy Technology Data Exchange (ETDEWEB)

    Kozubal, Eric Joseph

    2016-12-13

    An indirect evaporative cooler for cooling inlet supply air from a first temperature to a second, lower temperature using a stream of liquid coolant and a stream of exhaust or purge air. The cooler includes a first flow channel for inlet supply air and a second flow channel adjacent the first for exhaust air. The first and second flow channels are defined in part by sheets of a membrane permeable to water vapor such that mass is transferred as a vapor through the membrane from the inlet supply air to a contained liquid desiccant for dehumidification and also to the exhaust air as heat is transferred from the inlet supply air to the liquid coolant. A separation wall divides the liquid desiccant and the coolant but allows heat to be transferred from the supply air to the coolant which releases water vapor to the counter or cross flowing exhaust air.

  12. DC FLOW SUPPRESSION IN A SINGLE-STAGE G-M TYPE PULSE TUBE COOLER

    Institute of Scientific and Technical Information of China (English)

    JIANGYan-long; CHENGuo-bang; THUMMESGuenter

    2004-01-01

    An experimental investigation on DC flow suppression in a single-stage G-M type pulse tube cooler is made. The influence of DC flow induced by the introduction of the double-inlet on the refrigeration performance of the cooler is experimentally examined. Two parallelplaced needle valves with an opposite flow direction called as double-valved configuration, instead of conventional single-valved configuration as the double-inlet is used to reduce the DC flow. With the double-valved configuration, the minimum temperatures of 18.4 K and 14.7 K, and the cooling powers of 11.5 W and 29.5 W are also obtained by RW2 and CP4000, respectively.

  13. Comparison of Test Stand and Helicopter Oil Cooler Bearing Condition Indicators

    Science.gov (United States)

    Dempsey, Paula J.; Branning, Jeremy; Wade, Damiel R.; Bolander, Nathan

    2010-01-01

    The focus of this paper was to compare the performance of HUMS condition indicators (CI) when detecting a bearing fault in a test stand or on a helicopter. This study compared data from two sources: first, CI data collected from accelerometers installed on two UH-60 Black Hawk helicopters when oil cooler bearing faults occurred, along with data from helicopters with no bearing faults; and second, CI data that was collected from ten cooler bearings, healthy and faulted, that were removed from fielded helicopters and installed in a test stand. A method using Receiver Operating Characteristic (ROC) curves to compare CI performance was demonstrated. Results indicated the bearing energy CI responded differently for the helicopter and the test stand. Future research is required if test stand data is to be used validate condition indicator performance on a helicopter.

  14. Studies on an improved indigenous pressure wave generator and its testing with a pulse tube cooler

    Science.gov (United States)

    Jacob, S.; Karunanithi, R.; Narsimham, G. S. V. L.; Kranthi, J. Kumar; Damu, C.; Praveen, T.; Samir, M.; Mallappa, A.

    2014-01-01

    Earlier version of an indigenously developed Pressure Wave Generator (PWG) could not develop the necessary pressure ratio to satisfactorily operate a pulse tube cooler, largely due to high blow by losses in the piston cylinder seal gap and due to a few design deficiencies. Effect of different parameters like seal gap, piston diameter, piston stroke, moving mass and the piston back volume on the performance is studied analytically. Modifications were done to the PWG based on analysis and the performance is experimentally measured. A significant improvement in PWG performance is seen as a result of the modifications. The improved PWG is tested with the same pulse tube cooler but with different inertance tube configurations. A no load temperature of 130 K is achieved with an inertance tube configuration designed using Sage software. The delivered PV power is estimated to be 28.4 W which can produce a refrigeration of about 1 W at 80 K.

  15. Thermochemistry and Photochemistry in Cooler Hydrogen Dominated Extrasolar Planets: The Case of GJ436b

    CERN Document Server

    Line, Michael R; Chen, Pin; Angerhausen, D; Yung, Yuk L

    2011-01-01

    We introduce a new thermochemical kinetics and photochemical model. We use high-temperature bidirectional reaction rates for important H, C, O and N reactions (most importantly for CH$_4$ to CO interconversion), allowing us to attain thermochemical equilibrium, deep in an atmosphere, purely kinetically. This allows ab initio chemical modeling of an entire atmosphere, from deep-atmosphere thermochemical equilibrium to the photochemically dominated regime. We use our model to explore the atmospheric chemistry of cooler ($T_{eff} < 10^3$ K) extrasolar giant planets. In particular, we choose to model the nearby hot Neptune GJ436b, the only planet in this temperature regime for which spectroscopic measurements and estimates of chemical abundances now exist. Recent {\\it Spitzer} measurements with retrieval have shown that methane is driven strongly out of equilibrium and is deeply depleted on the dayside of GJ 436b, whereas quenched carbon monoxide is abundant. This is surprising because GJ 436b is cooler than m...

  16. The influence of the Thomson effect on the performance of a thermoelectric cooler

    Energy Technology Data Exchange (ETDEWEB)

    Mei Jiau Huang; Ruey Hor Yen [National Taiwan Univ. (China). Dept. of Mechanical Engineering; An Bang Wang [National Taiwan Univ. (China). Dept. of Applied Mathematics

    2005-01-01

    The temperature distribution of a thermoelectric cooler under the influence of the Thomson effect, the Joule heating, the Fourier's heat conduction, and the radiation and convection heat transfer is derived. The influence of the Thomson effect on the temperature profiles, on the fraction of the Joule's heat that flows back to the low-temperature side, and consequently on the maximum attainable temperature difference and the maximum allowable heat load are emphasized and explored. The results suggest that the cooling efficiency of a thermoelectric cooler can be improved not only by increasing the figure-of-merit of the thermoelectric materials but also by taking advantage of the Thomson effect. A possible development direction for the thermoelectric materials is thus given. (author)

  17. Modelling Aerosol Dispersion in Urban Street Canyons

    Science.gov (United States)

    Tay, B. K.; Jones, D. P.; Gallagher, M. W.; McFiggans, G. B.; Watkins, A. P.

    2009-04-01

    Flow patterns within an urban street canyon are influenced by various micrometeorological factors. It also represents an environment where pollutants such as aerosols accumulate to high levels due to high volumes of traffic. As adverse health effects are being attributed to exposure to aerosols, an investigation of the dispersion of aerosols within such environments is of growing importance. In particular, one is concerned with the vertical structure of the aerosol concentration, the ventilation characteristics of the street canyon and the influence of aerosol microphysical processes. Due to the inherent heterogeneity of the aerosol concentrations within the street canyon and the lack of spatial resolution of measurement campaigns, these issues are an on-going debate. Therefore, a modelling tool is required to represent aerosol dispersion patterns to provide insights to results of past measurement campaigns. Computational Fluid Dynamics (CFD) models are able to predict detailed airflow patterns within urban geometries. This capability may be further extended to include aerosol dispersion, by an Euler-Euler multiphase approach. To facilitate the investigation, a two-dimensional, multiphase CFD tool coupled with the k-epsilon turbulence model and with the capability of modelling mixed convection flow regimes arising from both wind driven flows and buoyancy effects from heated walls was developed. Assuming wind blowing perpendicularly to the canyon axis and treating aerosols as a passive scalar, an attempt will be made to assess the sensitivities of aerosol vertical structure and ventilation characteristics to the various flow conditions. Numerical studies were performed using an idealized 10m by 10m canyon to represent a regular canyon and 10m by 5m to represent a deep one. An aerosol emission source was assigned on the centerline of the canyon to represent exhaust emissions. The vertical structure of the aerosols would inform future directives regarding the

  18. Development of a 6-W high-reliability cryogenic cooler at Thales Cryogenics

    Science.gov (United States)

    Benschop, Tonny; Mullie, Jeroen C.; Bruins, Peter; Martin, Jean-Yves

    2003-01-01

    The demand for more cooling power for infrared imagers, which may require up to 3 W of cooling power at 77 K, is nowadays surpassed as other industries are getting interested in cryogenic cooling as well. These potential markets require robust, efficient and affordable coolers with cooling capacities in excess of 6 W. As announced at the previous SPIE conference in 2000, Thales Cryogenics has been working on the development of a cryocooler based on the LSF 918x series consisting of a flexure bearing compressor in combination with a 20 mm Stirling cold finger in order to meet the demands of this emerging markets. Based on the proven principles of Thales LSF 91xx flexure bearing compressors, a moving magnet compressor was designed that delivers the required pressure wave for this larger cold finger. The compressor has been successfully tested in combination with the 20 mm cold finger resulting in the LSF 93xx cooler. For the second half of 2002, tests are planned for the combination of a version of this compressor with a 5 W pulse tube cold finger. At present, the European Space Agency is funding the space qualification of a modification the LSF 93xx cooler, in order to use it to provide the cryogenic cooling required for future manned missions. A test program for the specific requirements for the CRYOSYSTEM program is under progress. This paper describes the trade-offs that have been considered in the design phase, and gives a detailed overview of the test results and the resulting specification of the LSF 93xx coolers.

  19. Energy analysis of the cryogenic CO2 capture process based on Stirling coolers

    OpenAIRE

    Song, Chunfeng; Kitamura, Yutaka; Li, Shuhong

    2014-01-01

    In the existing coal-fired power plants, the energy penalty associated with CO2 capture process is an important challenge. For this reason, energy analysis has been widely used as a powerful tool to optimize the capture efficiency and reduce energy consumption. In our previous work, a Stirling cooler based cryogenic CO2 capture system was outlined. Process simulation and energy analysis of the system were undertaken in this research. The whole CO2 capture process is composed of three sections...

  20. Vibration Control of Linear Split Stirling Cryogenic Cooler for Airborne Infrared Application

    OpenAIRE

    A.M. Veprik; V.I. Babitsky; N. Pundak; S.V. Riabzev

    2000-01-01

    Modern infrared imagers often rely on the split Stirling cryogenic coolers the linear compressors of which are the well-known sources of harmonic disturbance. The traditional method of their passive isolation fails to meet the restraints on the static and dynamic deflections which are originated by the combined action of the airborne g-loading and harsh random vibration.The vibration protection system, which combines a stiff and heavily damped vibration isolator with tuned dynamic absorber, i...

  1. FPGA-BASED CONTROL OF THERMOELECTRIC COOLERS FOR LASER DIODE TEMPERATURE REGULATION

    Directory of Open Access Journals (Sweden)

    AHTESHAM ALI

    2012-04-01

    Full Text Available The proportional-integral-derivative (PID controller is the most used controller in the industry. Field programmable gate arrays (FPGAs allow efficient implementation of PID controllers. This paper presents the temperature regulation of a 48W laser diode through thermoelectric coolers (TECs. The temperature regulation system is designed and tested. The results demonstrate the feasibility and applicability of PID control through FPGA.

  2. Sorption-based vibration-free cooler for the METIS instrument on E-ELT

    Science.gov (United States)

    ter Brake, H. J. M.; Wu, Y.; Zalewski, D. R.; Vermeer, C. H.; Holland, H. J.; Doornink, J.; Benthem, B.; Boom, E.

    2012-09-01

    METIS is the 'Mid-infrared ELT Imager and Spectrograph' for the European Extremely Large Telescope. This E-ELT instrument will cover the thermal/mid-infrared wavelength range from 3 to 14 μm and will require cryogenic cooling of detectors and optics. We present a vibration-free cooling technology for this instrument based on sorption coolers developed at the University of Twente in collaboration with Dutch Space. In the baseline design, the instrument has four temperature levels: N-band: detector at 8 K and optics at 25 K; L/M-band: detector at 40K and optics at 77 K. The latter temperature is established by a liquid nitrogen supply with adequate cooling power. The cooling powers required at the lower three levels are 0.4 W, 1.1 W, and 1.4 W, respectively. The cryogenic cooling technology that we propose uses a compressor based on the cyclic adsorption and desorption of a working gas on a sorber material such as activated carbon. Under desorption, a high pressure can be established. When expanding the high-pressure fluid over a flow restriction, cooling is obtained. The big advantage of this cooling technology is that, apart from passive valves, it contains no moving parts and, therefore, generates no vibrations. This, obviously, is highly attractive in sensitive, high-performance optical systems. A further advantage is the high temperature stability down to the mK level. In a Dutch national research program we aim to develop a cooler demonstrator for METIS. In the paper we will describe our cooler technology and discuss the developments towards the METIS cooler demonstrator.

  3. DNA profiling from heroin street dose packages.

    Science.gov (United States)

    Zamir, Ashira; Cohen, Yaron; Azoury, Myriam

    2007-03-01

    A large amount of heroin street doses are seized and examined for drug content by the Israel police. These are generally wrapped in heat-sealed plastic. Occasionally it is possible to visualize latent fingerprints on the plastic wrap itself, but the small size of the plastic item and the sealing process makes the success rate very low. In this study, the possibility of extracting and profiling DNA from the burnt edge of the plastic wrap was investigated. The idea was based on the assumption that epithelial cells might be trapped during the sealing process. The results show that there are sufficient quantities of DNA deposited at the "amorphic" burnt edges of sealed street doses for DNA profiling to be carried out. A controlled experiment using a known donor was performed. This subject carried out sealing of "street drug" packages and consequent DNA extractions were performed to show that known DNA profiles could be recovered from such packages, as a result of handling by the "packer." "Square-like" burnt edges did not yield DNA profiles, probably because of differences in the sealing process. It was also shown that DNA could be recovered from the plastic wrap itself and not only from the amorphic burnt edges. As heroin dealers and drug users are often involved in other crimes and run-ins with the law, the effective extraction and addition of their DNA profiles from such items of evidence to the newly established DNA database in Israel provides new avenues in the continued fight against crime and drug traffickers.

  4. Potential reductions of street solids and phosphorus in urban watersheds from street cleaning, Cambridge, Massachusetts, 2009-11

    Science.gov (United States)

    Sorenson, Jason R.

    2013-01-01

    Material accumulating and washing off urban street surfaces and ultimately into stormwater drainage systems represents a substantial nonpoint source of solids, phosphorus, and other constituent loading to waterways in urban areas. Cost and lack of usable space limit the type and number of structural stormwater source controls available to municipalities and other public managers. Non-structural source controls such as street cleaning are commonly used by cities and towns for construction, maintenance and aesthetics, and may reduce contaminant loading to waterways. Effectiveness of street cleaning is highly variable and potential improvements to water quality are not fully understood. In 2009, the U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, the U.S. Environmental Protection Agency, and the city of Cambridge, Massachusetts, and initiated a study to better understand the physical and chemical nature of the organic and inorganic solid material on street surfaces, evaluate the performance of a street cleaner at removing street solids, and make use of the Source Loading and Management Model (SLAMM) to estimate potential reductions in solid and phosphorus loading to the lower Charles River from various street-cleaning technologies and frequencies. Average yield of material on streets collected between May and December 2010, was determined to be about 740 pounds per curb-mile on streets in multifamily land use and about 522 pounds per curb-mile on commercial land-use streets. At the end-of-winter in March 2011, about 2,609 and 4,788 pounds per curb-mile on average were collected from streets in multifamily and commercial land-use types, respectively. About 86 percent of the total street-solid yield from multifamily and commercial land-use streets was greater than or equal to 0.125 millimeters in diameter (or very fine sand). Observations of street-solid distribution across the entire street width indicated that as

  5. Design of an electron cooling device for the accumulator cooler ring in MUSES project

    CERN Document Server

    Tanabé, T; Ohtomo, K; Katayama, T; Yamashita, A; Syresin, E M; Meshkov, I N

    2000-01-01

    As a part of new experimental facility in the Radio Isotope Beam Factory (RIBF) project at RIKEN, the Multi-Use Experimental Storage rings (MUSES) have an Accumulator Cooler Ring (ACR) which is used for both the accumulation and cooling of RI beams and various experiments. Besides a stochastic cooler, an electron cooler (EC) is presently under development. The ion energy in the ACR ranges from 60 to 400 MeV/u which corresponds to the electron beam (e-beam) energy for the EC from 30 to 250 kV. The maximum current from a 12.7 mm cathode is 4.1 A with a gun perveance of 0.79 mu P. A superconducting solenoid in the gun section generates a magnetic field of 4 T which corresponds to a factor of 20 in adiabatic expansion. The design issues of the gun section, collector, toroidal magnets and compensation solenoids are discussed in detail with some retrospection of the development.

  6. Interfacial Engineering of Semiconductor-Superconductor Junctions for High Performance Micro-Coolers

    Science.gov (United States)

    Gunnarsson, D.; Richardson-Bullock, J. S.; Prest, M. J.; Nguyen, H. Q.; Timofeev, A. V.; Shah, V. A.; Whall, T. E.; Parker, E. H. C.; Leadley, D. R.; Myronov, M.; Prunnila, M.

    2015-12-01

    The control of electronic and thermal transport through material interfaces is crucial for numerous micro and nanoelectronics applications and quantum devices. Here we report on the engineering of the electro-thermal properties of semiconductor-superconductor (Sm-S) electronic cooler junctions by a nanoscale insulating tunnel barrier introduced between the Sm and S electrodes. Unexpectedly, such an interface barrier does not increase the junction resistance but strongly reduces the detrimental sub-gap leakage current. These features are key to achieving high cooling power tunnel junction refrigerators, and we demonstrate unparalleled performance in silicon-based Sm-S electron cooler devices with orders of magnitudes improvement in the cooling power in comparison to previous works. By adapting the junctions in strain-engineered silicon coolers we also demonstrate efficient electron temperature reduction from 300 mK to below 100 mK. Investigations on junctions with different interface quality indicate that the previously unexplained sub-gap leakage current is strongly influenced by the Sm-S interface states. These states often dictate the junction electrical resistance through the well-known Fermi level pinning effect and, therefore, superconductivity could be generally used to probe and optimize metal-semiconductor contact behaviour.

  7. Numerical modeling of the thermoelectric cooler with a complementary equation for heat circulation in air gaps

    Science.gov (United States)

    Fang, En; Wu, Xiaojie; Yu, Yuesen; Xiu, Junrui

    2017-03-01

    In this paper, a numerical model is developed by combining thermodynamics with heat transfer theory. Taking inner and external multi-irreversibility into account, it is with a complementary equation for heat circulation in air gaps of a steady cooling system with commercial thermoelectric modules operating in refrigeration mode. With two modes concerned, the equation presents the heat flowing through air gaps which forms heat circulations between both sides of thermoelectric coolers (TECs). In numerical modelling, a TEC is separated as two temperature controlled constant heat flux reservoirs in a thermal resistance network. In order to obtain the parameter values, an experimental apparatus with a commercial thermoelectric cooler was built to characterize the performance of a TEC with heat source and sink assembly. At constant power dissipation, steady temperatures of heat source and both sides of the thermoelectric cooler were compared with those in a standard numerical model. The method displayed that the relationship between Φf and the ratio Φ_{c}'/Φ_{c} was linear as expected. Then, for verifying the accuracy of proposed numerical model, the data in another system were recorded. It is evident that the experimental results are in good agreement with simulation(proposed model) data at different heat transfer rates. The error is small and mainly results from the instabilities of thermal resistances with temperature change and heat flux, heat loss of the device vertical surfaces and measurements.

  8. Experimental Investigation of Using Evaporative Air Cooler for Winter Air-Conditioning in Baghdad

    Directory of Open Access Journals (Sweden)

    Zainab Hasson Hassan

    2012-01-01

    Full Text Available This paper presents an efficient methodology to design modified evaporative air-cooler for winter air-conditioning in Baghdad city as well as using it for summer air-conditioning by adding a heating process after the humidification process. Laboratory tests were performed on a direct evaporative cooler (DEC followed by passing the air on hot water through heat exchanger placed in the coolers air duct exit. The tests were conducted on the 2nd of December /2011 when the ambient temperature was 8.1°C and the relative humidity was (68%. The air flow rate is assumed to vary between 0.069 to 0.209 kg/s with constant water flow rate of 0.03 kg/s in the heat exchanger. The performance is reported in terms of effectiveness of DEC, saturation efficiency of DEC, outlet temperature of air and cooling capacity. Heat transfer rate in heat exchanger mode is also estimated. The paper presents the mathematical development of the equations of thermal exchanges through DEC and HE. Prediction of air condition that exits o this system show that the present system could bring the air stream to a comfortable winter zone .

  9. Optimisation of a desiccant cooling system design with indirect evaporative cooler

    Energy Technology Data Exchange (ETDEWEB)

    Goldsworthy, M.; White, S. [CSIRO Energy Technology, 10 Murray Dwyer Cr., Mayfield, 2300 Newcastle (Australia)

    2011-01-15

    Solar desiccant-based air-conditioning has the potential to significantly reduce cost and/or greenhouse gas emissions associated with cooling of buildings. Parasitic energy consumption for the operation of supply fans has been identified as a major hindrance to achieving these savings. The cooling performance is governed by the trade-off between supplying larger flow-rates of cool air or lower flow-rates of cold air. The performance of a combined solid desiccant-indirect evaporative cooler system is analysed by solving the heat and mass transfer equations for both components simultaneously. Focus is placed on varying the desiccant wheel supply/regeneration and indirect cooler secondary/primary air-flow ratios. Results show that for an ambient reference condition, and 70 C regeneration temperature, a supply/regeneration flow ratio of 0.67 and an indirect cooler secondary/primary flow ratio of 0.3 gives the best performance with COP{sub e} > 20. The proposed cooling system thus has potential to achieve substantial energy and greenhouse gas emission savings. (author)

  10. Effects of polyethylene film wrap on cooler shrink and the microbial status of beef carcasses.

    Science.gov (United States)

    Sampaio, Guilherme S L; Pflanzer-Júnior, Sérgio B; Roça, Roberto de O; Casagrande, Leandro; Bedeschi, Elaine A; Padovani, Carlos R; Miguel, Giulianna Z; Santos, Carolina T; Girão, Lucio V C; Miranda, Zander B; Franco, Robson M

    2015-02-01

    The present study evaluated the use of polyethylene film wrapping of beef half carcasses and its effects on cooler shrink, cooling characteristics and microbial status of the half carcasses. Film wrapping reduced cooler shrink by 55.2%, 43.1%, 36.0% and 30% after 24, 48, 72 and 96 h of cooling, respectively, compared to the unwrapped half carcasses, whereas the surface water activity showed no significant differences among the time periods. The wrapped half carcasses had a lower cooling rate and higher surface and internal temperatures. The highest values of the aerobic mesophiles, Staphylococcus aureus and Enterobacteriaceae were found in the half carcasses wrapped in film. No significant differences were found in the values of Escherichia coli. The polyethylene film was effective in reducing cooler shrink; however, it caused a delay in cooling, thereby enabling greater microbial occurrences and counts and impairing the hygienic and sanitary conditions of the carcasses, which may be an impediment to the practical application of this technology.

  11. Performance of four-stage thermoelectric cooler for extended wavelength InGaAs detectors

    Science.gov (United States)

    Mo, De-feng; Yang, Li-yi; Liu, Da-fu; Xu, Qin-fei; Li, Tao; Li, Xue

    2015-04-01

    Experimental setup for evaluating four-stage thermoelectric cooler's performance was designed. Effects of input power, heat dissipation condition and heat load on the temperature difference (ΔT) of four-stage thermoelectric coolers' hot and cold faces were obtained experimentally. The result shows that, the ΔT increases as the input power increases. A linear relationship exists between input current and feedback voltage. In different cooling conditions, the ΔT of thermoelectric cooler (TEC) increases with the temperature of hot face. As the temperature increasing on hot face is 1K, the ΔT increasing of TEC can be about 0.5K. Meanwhile, the power consumption of TEC also increases slightly. Water condensation can be prevented in either dry nitrogen environment or vacuum environment, but the vacuum level has great influence to the ΔT, especially in low operation temperature. The better the vacuum level is, the smaller the convection heat loss has. When the operation temperature of focal plane array (FPA) is lower than 220K, it is prior to use vacuum packaging. Considering the Joule-heat of readout circuit and the heat loss of wire conduction, the minimum working temperature of FPA can reach below 200 K when the temperature of the hot face is 285K. And the coefficient of performance (COP) of TEC can increase sharply from 0.8% to 4% when the controlled operation temperature is 220K rather than 200K.

  12. Status of the JWST/MIRI Focal Plane System and Cooler

    Science.gov (United States)

    Ressler, Michael E.; Goodson, G. B.; Khorrami, M. A.; Larson, M. E.; Mahoney, J. C.; Sukhatme, K. G.

    2009-01-01

    The Mid-Infrared Instrument (MIRI) is a multipurpose imager, coronagraph, and spectrometer for the James Webb Space Telescope. It provides wavelength coverage from 5 through 28 microns and is an integral contributor to all four of JWST's primary science themes. MIRI is being developed as a partnership between NASA and ESA, with JPL providing the Focal Plane System (FPS, consisting of the detectors, control electronics, and flight software) and the cooler, and a consortium of European astronomical institutes providing the optical bench and structure. The flight FPS is being prepared for delivery to the European Consortium for its integration into the optical bench, while the cooler is nearing its Critical Design Review. We describe the capabilities of the FPS and cooler, present test results and the predicted sensitivity performance of the FPS, and update the current status of each these systems. The research described in this poster was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

  13. A study of sound absorption by street canyon boundaries and asphalt rubber concrete pavement

    Science.gov (United States)

    Drysdale, Graeme Robert

    A sound field model, based on a classical diffusion equation, is extended to account for sound absorption in a diffusion parameter used to model sound energy in a narrow street canyon. The model accounts for a single sound absorption coefficient, separate accommodation coefficients and a combination of separate absorption and accommodation coefficients from parallel canyon walls. The new expressions are compared to the original formula through numerical simulations to reveal the effect of absorption on sound diffusion. The newly established analytical formulae demonstrate satisfactory agreement with their predecessor under perfect reflection. As well, the influence of the extended diffusion parameter on normalized sound pressure levels in a narrow street canyon is in agreement with experimental data. The diffusion parameters are used to model sound energy density in a street canyon as a function of the sound absorption coefficient of the street canyon walls. The acoustic and material properties of conventional and asphalt rubber concrete (ARC) pavement are also studied to assess how the crumb rubber content influences sound absorption in street canyons. The porosity and absolute permeability of compacted specimens of asphalt rubber concrete are measured and compared to their normal and random incidence sound absorption coefficients as a function of crumb rubber content in the modified binder. Nonlinear trends are found between the sound absorption coefficients, porosity and absolute permeability of the compacted specimens and the percentage of crumb rubber in the modified binders. The cross-sectional areas of the air voids on the surfaces of the compacted specimens are measured using digital image processing techniques and a linear relationship is obtained between the average void area and crumb rubber content. The measured material properties are used to construct an empirical formula relating the average porosity, normal incidence noise reduction coefficients and

  14. CONTROLLING STREET DOG POPULATION IN MOSCOW

    OpenAIRE

    ZHULENKO A.S.; POLYNOVA G.V.

    2016-01-01

    The issue represents the analysis of the fundamentals and world-wide best practices of controlling street dog population in Moscow and other global cities. Actions proposed to improve the strategy of managing free-ranging dogs in Moscow.Some reasons of increase in number of stray dogs and “pet overpopulation” ware studied. There are ecological types of stray dogs characterized the types of running wild of dogs and foraging (food procurement) strategy of animals.The analysis of the basic princ...

  15. Politicians, Managers, and Street-Level Bureaucrats

    DEFF Research Database (Denmark)

    J. May, Peter; Winter, Søren

    2012-01-01

    This article addresses the influence of politicians, managers, and the dispositions of street level bureaucrats in shaping actions at the frontlines of policy implementation. We investigate these for the implementation of employment policy reforms in Denmark. Our findings show a large percentage...... of caseworkers emphasizing actions that are consistent with thenational employment reform goal of getting clients into jobs quickly. The influence of politicians and managers in bringing this about is relatively limited in comparison to the influences of caseworkers’ understanding of policy goals...

  16. Politicians, Managers, and Street-Level Bureaucrats

    DEFF Research Database (Denmark)

    J. May, Peter; Winter, Søren

    2009-01-01

    This article addresses the influence of politicians, managers, and the dispositions of street-level bureaucrats in shaping actions at the frontlines of policy implementation. We investigate these for the implementation of employment policy reforms in Denmark. Our findings show a large percentage...... of caseworkers emphasizing actions that are consistent with the national employment reform goal of getting clients into jobs quickly. The influence of politicians and managers in bringing this about is relatively limited in comparison to the influences of caseworkers’ understanding of policy goals...

  17. Graffiti e street art em Portugal

    OpenAIRE

    Simões, Marta Correia

    2014-01-01

    Tese de mestrado, Arte, Património e Teoria do Restauro, Universidade de Lisboa, Faculdade de Letras, 2014 O seguinte trabalho tem como principal objectivo introduzir o estudo do graffiti e da street art no seio da história da arte em Portugal, como uma forma de arte contemporânea. O graffiti tem vindo a acompanhar a humanidade ao longo da história. De uma forma inconstante, este teve as mais diversas utilizações e é hoje considerado como um movimento artístico. Partindo de um estudo da...

  18. A social work study on family patterns and street children

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Iravani

    2014-06-01

    Full Text Available This paper presents a social work study on relationship between various family characteristics and street children in rural area as well as city of Esfahan, Iran. The proposed study selects a sample of 150 street children, 75 from city and 75 from rural area, and using some statistical tests verifies the effects of three factors including family income, place of residency and family size on street children. The results indicate that the city residence had more street children than rural residence did. In addition, there was a meaningful difference between the number of street children in low-income families and high-income families. Finally, the survey results indicate that big size families more likely suffered from street children than low size families did.

  19. [Street social education: historical, political and pedagogical bases].

    Science.gov (United States)

    de Oliveira, Walter Ferreira

    2007-01-01

    This work is about street social education as a pedagogical system that started in Latin America in the late 1970s, as the street population formed mostly by children and adolescents called for attention. The first street social educators were 'pastoral' agents working at the praça da Sé a place with large numbers of street children in São Paulo. Based on the Liberation Theology and on the pedagogies developed by Paulo Freire, Celestine Freinet, Anton Makarenko, and Emília Ferreiro, the street educators developed a conceptual field and participated in the promulgation of the 1988 Federal Constitution, particularly by writing and introducing the 'Estatuto da Criança e do Adolescente' (the 'Child and Adolescent Statute'). Street social education is currently latent and suffering the consequences of program discontinuity caused by successive changes of government. It is, therefore important to know the conceptual proposals.

  20. The initiation of homeless youth into the street economy.

    Science.gov (United States)

    Gwadz, Marya Viorst; Gostnell, Karla; Smolenski, Carol; Willis, Brian; Nish, David; Nolan, Theresa C; Tharaken, Maya; Ritchie, Amanda S

    2009-04-01

    Homeless youth (HY) who lack employment in the formal economy typically turn to the street economy (e.g., prostitution, drug selling) for survival. Guided by the theory of social control, the present paper explores factors influencing HY's initiation into the street economy. Eighty HY (ages 15-23) were recruited from four community-based organizations. All participated in structured interviews and 25% participated in qualitative interviews. Almost all HY had participated in the street (81%) and formal economies (69%). Five main factors simultaneously influenced initiation into the street economy: social control/bonds, barriers to the formal economy (e.g., homelessness, educational deficits, mental health problems, incarceration, stigma), tangible and social/emotional benefits of the street economy, severe economic need, and the active recruitment of HY into the street economy by others. Qualitative and quantitative data sources were congruent. Intervention efforts are needed at multiple levels of influence to promote HY's success in the formal economy.

  1. [Addictive behavior of street children: interculturation and resilience].

    Science.gov (United States)

    Kommegne, T; Denoux, P; Bernoussi, A; Njiengwe, E F

    2014-09-01

    This research belongs to a more comprehensive study on the care of street children in Cameroon. The idea is to develop an analysis of the street pathology where symptoms such as addictive behavior and drug addiction can be found. Beside HIV AIDS, addictive behaviors are the main risk factors that many professionals have to face with while dealing with the street problems today. Through an intercultural approach, we examined the practices of addictive typology, their initiatory role and their function in the integration of the street system. We also analysed their importance in the survival strategies. After an overview of theoretical controversies that feed the debate on addictions, we questioned the impact of these practices on the street career through the prism of general theory of addictions, particularly the hedonic management model. Addiction helps to resist adversity, it helps to desist and then to begin a harmonious neo development despite the horrors of the street experience. We undertook a quantitative and qualitative study on a sample of 148 street children. We proposed to 128 of them a questionnaire focused on addictive behaviors and survival strategies in the street context. We notably evaluated the street career of 24 of them, using interviews and standardized tests to assess self-esteem (Coopersmith's SEI) frustration tolerance (Rosenweig's P-F) and self-efficacy (Sherer's SE Scale) in order to measure the impact of addictive behaviors on the resilience process. We found that the street career is essentially traumatic, and that addictive behaviors involving various integration strategies are strongly linked to the interculturation process through the identity strategies and the intercultural competences. Addiction itself is not significantly related to self-esteem issues but strongly impacts on self-efficacy and the ability to tolerate frustration. They allow the street children to withstand the street adversity but are a real obstacle to their

  2. Urban road design according to NACTO Urban Street Design Guide

    OpenAIRE

    Velkavrh, Lara

    2016-01-01

    Urban road design according to NACTO follows the vision of traffic calming with visual elements. Gradual restoration of urban traffic areas will be presented according to american guidelines of NACTO Association, which published a book in 2013 called Urban Street Design Guide. Each type of existing roads in the urban area (the main street, the road in the neighborhood, residential shared street) can be, step by step, reconstructed with individual structural elements to ensure greater safety f...

  3. "Hitting the Streets": Youth Street Involvement as Adaptive Well-Being

    Science.gov (United States)

    Brown, Tara A.

    2016-01-01

    Youth involved in illegal street activities such as drug trafficking and violence are at high risk for school failure and other negative outcomes. Research often seeks to identify what is "wrong" with them, what makes them different from "normal" youth, but relatively few studies focus on variations in how youth engage in and…

  4. The Ballet of the Streets: Teaching about Cities at Street Level

    Science.gov (United States)

    McGuire, Patrick A.; Spates, James L.

    2011-01-01

    The urban scholar Jane Jacobs once described city life as "the ballet of the streets." In more than a quarter century of joint teaching, the authors have used Jacobs' metaphor to help their students understand that cities are living organisms created and maintained, for good or ill, by the people who live and work in them. At heart their…

  5. "Hitting the Streets": Youth Street Involvement as Adaptive Well-Being

    Science.gov (United States)

    Brown, Tara A.

    2016-01-01

    Youth involved in illegal street activities such as drug trafficking and violence are at high risk for school failure and other negative outcomes. Research often seeks to identify what is "wrong" with them, what makes them different from "normal" youth, but relatively few studies focus on variations in how youth engage in and…

  6. Working on the street and exposure to violence at work: a study with traffic agents

    Directory of Open Access Journals (Sweden)

    Selma Lancman

    2007-01-01

    Full Text Available This study was done with transit agents, who for various reasons related to the organization of their work and the fact that the street is their work space, are exposed to situations of intense verbal, and sometimes physical, aggression. By studying this situation it is hoped to make a contribution to understanding the impact of violence on the mental health of workers who work on the streets and its reflections in their health, their work development and relationships. This study was based on theoretical/methodological principles of the psychodynamics of work. This is a reserach-action method in which doing research presupposes having a transformative action on the situation studied. We verified that living with violence in the exercise of their profession has a strong impact on workers' mental health on the one hand, and on the other, they develop strategies and use work-related intelligence in order to be able to continue working.

  7. Different Ways of Thinking about Street Networks and Spatial Analysis

    CERN Document Server

    Jiang, Bin

    2014-01-01

    Street networks, as one of the oldest infrastructures of transport in the world, play a significant role in modernization, sustainable development, and human daily activities in both ancient and modern times. Although street networks have been well studied in a variety of engineering and scientific disciplines, including for instance transport, geography, urban planning, economics, and even physics, our understanding of street networks in terms of their structure and dynamics remains limited, especially when dealing with such real-world problems as traffic jams, pollution, and human evacuations for disaster management. One goal of this special issue is to promote different ways of thinking about understanding street networks, and of conducting spatial analysis.

  8. Into a Mapping of Copenhagen Street Lighting 2014

    DEFF Research Database (Denmark)

    Bülow, Katja; Asp, Claus; Kongshaug, Jesper

    2015-01-01

    LED lighting is a new lighting component in urban Spaces. How does LED lighting change the visual experience of a street, how did it use to be and how will it become? The book presents a mapping method in which an overview map of light sources in the Copenhagen streets is combined with a video...... recording and a series of photos from a route, whick goes through different city parts and types of streets. The mapping is done in the crucial changing fase, in which the street lighting in Copenhagen is a mix of previously used light sources and LED....

  9. Reflective Writing

    DEFF Research Database (Denmark)

    Ahrenkiel Jørgensen, Andriette

    2016-01-01

    Høeg etetera. The dialogues work as a tool of reflection in terms of providing opportunity to examine his own beliefs, to explore the possible reasons for engaging in a particular activity. On the basis of Sven-Ingvar Andersson’s book a teaching program at the Aarhus School of Architecture provides...... a contribution to the discussions about the role of reflection in design work and in learning situations at large. By engaging with the dialogic reflection, which is one of the four essential types of reflection, (the three others being descriptive writing, descriptive reflection and critical reflection...

  10. Multicity HIV seroprevalence in street youth, Ukraine.

    Science.gov (United States)

    Robbins, C L; Zapata, L; Kissin, D M; Shevchenko, N; Yorick, R; Skipalska, H; Finnerty, E; Ornstein, T; Marchbanks, P A; Jamieson, D J; Hillis, S D

    2010-07-01

    We conducted the first systematic, community-based, multicity assessment outside the USA of HIV seroprevalence, risk factors and linkage into clinical services among 929 street youth. After city-wide mapping, we used time-location sampling and randomly selected 74 venues in Odesa, Kyiv and Donetsk, Ukraine. Rapid HIV testing with post-test counselling was offered to all eligible youths aged 15-24 years. Overall, 18.4% (95% confidence interval 16.2-20.2) were HIV positive and 85% had previously unknown status. Rates were identical by sex. Subgroups with highest rates included orphans (26%), youths with histories of exchanging sex (35%), sexually transmitted infections (STIs) (37%), injection drug use (IDU) (42%) and needle sharing (49%). Independent predictors, similar across age groups and city, included being orphaned, time on the street, history of anal sex, STIs, exchanging sex, any drug use, IDU and needle sharing. Two-thirds (68%) of HIV-positive youths were linked to services. This high-risk population has many immediate needs.

  11. Green Streets: Urban Green and Birth Outcomes.

    Science.gov (United States)

    Abelt, Kathryn; McLafferty, Sara

    2017-07-13

    Recent scholarship points to a protective association between green space and birth outcomes as well a positive relationship between blue space and wellbeing. We add to this body of literature by exploring the relationship between expectant mothers' exposure to green and blue spaces and adverse birth outcomes in New York City. The Normalized Difference Vegetation Index (NDVI), the NYC Street Tree Census, and access to major green spaces served as measures of greenness, while proximity to waterfront areas represented access to blue space. Associations between these factors and adverse birth outcomes, including preterm birth, term birthweight, term low birthweight, and small for gestational age, were evaluated via mixed-effects linear and logistic regression models. The analyses were conducted separately for women living in deprived neighborhoods to test for differential effects on mothers in these areas. The results indicate that women in deprived neighborhoods suffer from higher rates adverse birth outcomes and lower levels of residential greenness. In adjusted models, a significant inverse association between nearby street trees and the odds of preterm birth was found for all women. However, we did not identify a consistent significant relationship between adverse birth outcomes and NDVI, access to major green spaces, or waterfront access when individual covariates were taken into account.

  12. Data and life on the street

    Directory of Open Access Journals (Sweden)

    Alex S Taylor

    2014-07-01

    Full Text Available What does the abundance of data and proliferation of data-making methods mean for the ordinary person, the person on the street? And, what could they come to mean? In this paper, we present an overview of a year-long project to examine just such questions and complicate, in some ways, what it is to ask them. The project is a collective exercise in which we – a mixture of social scientists, designers and makers – and those living and working on one street in Cambridge (UK, Tenison Road, are working to think through how data might be materialised and come to matter. The project aims to better understand the specificities and contingencies that arise when data is produced and used in place. Mid-way through the project, we use this commentary to give some background to the work and detail one or two of the troubles we have encountered in putting locally relevant data to work. We also touch on a methodological standpoint we are working our way into and through, one that we hope complicates the separations between subject and object in data-making and opens up possibilities for a generative refiguring of the manifold relations.

  13. EVALUATION OF DYNAMIC CARACTERISTICS OF GAS COOLER OF THE CARBON DIOXIDE HEAT PUMP ÎN THE TRANSCRITICAL CYCLE

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2008-12-01

    Full Text Available Dynamic characteristics of heat pump gas cooler obtained by means of the solution of the dynamics equations in partial derivatives are examined. Control system of the heat pump used for the heating of the heating–system water, supplied from CHP to the district heating system is examined. Possibility of PID-controller with gain scheduling utilization with the coefficients changing depending on gas cooler mode of operation for temperature disturbances compensation of direct heating–system water is shown.

  14. Study on the COP of free piston Stirling cooler (FPSC) in the anti-sublimation CO2 capture process

    OpenAIRE

    Song, Chunfeng; Lu, Jingwen; Kitamura, Yutaka

    2015-01-01

    Free piston Stirling cooler (FPSC) is a promising alternative for the conventional coolers and has been applied to various fields. In the previous research, a novel cryogenic CO2 capture system based on FPSCs has been exploited. In order to enhance the cryogenic CO2 capture efficiency, the investigation on the coefficient of performance (COP) of the FPSC is carried out in this work. In detail, the influence of different materials (aluminium and copper), size of cold head (length and diameter)...

  15. Process Calculation for Reciprocating Compressor Cooler%往复压缩机冷却器的工艺计算

    Institute of Scientific and Technical Information of China (English)

    李首霖; 姜晓川; 郭淑英

    2015-01-01

    Set the process calculation for reciprocating compressor cooler as an example, this paper briefly specified the process cal-culation method for cooler applying HTRI software and the practical meanings.%以往复压缩机用的冷却器工艺计算为例,简述了应用HTRI软件对冷却器进行工艺计算的方法以及实用意义。

  16. Simulating the impacts of on-street vehicle parking on traffic operations on urban streets using cellular automation

    Science.gov (United States)

    Chen, Jingxu; Li, Zhibin; Jiang, Hang; Zhu, Senlai; Wang, Wei

    2017-02-01

    In recent years, many bicycle lanes on urban streets are replaced with vehicle parking places. Spaces for bicycle riding are reduced, resulting in changes in bicycle and vehicle operational features. The objective of this study is to estimate the impacts of on-street parking on heterogeneous traffic operation on urban streets. A cellular automaton (CA) model is developed and calibrated to simulate bicycle lane-changing on streets with on-street parking. Two types of street segments with different bicycle lane width are considered. From the simulation, two types of conflicts between bicycles and vehicles are identified which are frictional conflicts and blocking conflicts. Factors affecting the frequency of conflicts are also identified. Based on the results, vehicle delay is estimated for various traffic situations considering the range of occupancy levels for on-street parking. Later, a numerical network example is analyzed to estimate the network impact of on-street parking on traffic assignment and operation. Findings of the study are helpful to policies and design regarding on-street vehicle parking to improve the efficiency of traffic operations.

  17. Violence and the code of the street: a study of social dynamics among street children in Makeevka, East Ukraine.

    Science.gov (United States)

    Naterer, Andrej

    2015-05-01

    This article explores violence among street children in Makeevka, Ukraine. Drawing on qualitative and quantitative data gathered during longitudinal field research, extra-, intra-, and inter-group violence is analyzed with an emphasis on the child's situational interpretation and adoption of the code of the street through subsequent code/identity switching and subcultural reactions. The main findings suggest that street children subculture has developed a unique code based on the need to survive and on solidarity and reciprocity; violent acts emerging among them must be understood within this context. The influence of violence on the children's lives and street careers is considered, and alternative explanations of violence are discussed.

  18. 75 FR 71744 - Fifth Street Finance Corp., et al.; Notice of Application

    Science.gov (United States)

    2010-11-24

    ... COMMISSION Fifth Street Finance Corp., et al.; Notice of Application November 18, 2010. AGENCY: Securities... Finance Corp. (``Fifth Street''), Fifth Street Management LLC, Fifth Street Mezzanine Partners IV, L.P... regulated as a business development company (``BDC'') under the Act. Fifth Street is a specialty finance...

  19. Street Choice Logit Model for Visitors in Shopping Districts

    Directory of Open Access Journals (Sweden)

    Ko Kawada

    2014-07-01

    Full Text Available In this study, we propose two models for predicting people’s activity. The first model is the pedestrian distribution prediction (or postdiction model by multiple regression analysis using space syntax indices of urban fabric and people distribution data obtained from a field survey. The second model is a street choice model for visitors using multinomial logit model. We performed a questionnaire survey on the field to investigate the strolling routes of 46 visitors and obtained a total of 1211 street choices in their routes. We proposed a utility function, sum of weighted space syntax indices, and other indices, and estimated the parameters for weights on the basis of maximum likelihood. These models consider both street networks, distance from destination, direction of the street choice and other spatial compositions (numbers of pedestrians, cars, shops, and elevation. The first model explains the characteristics of the street where many people tend to walk or stay. The second model explains the mechanism underlying the street choice of visitors and clarifies the differences in the weights of street choice parameters among the various attributes, such as gender, existence of destinations, number of people, etc. For all the attributes considered, the influences of DISTANCE and DIRECTION are strong. On the other hand, the influences of Int.V, SHOPS, CARS, ELEVATION, and WIDTH are different for each attribute. People with defined destinations tend to choose streets that “have more shops, and are wider and lower”. In contrast, people with undefined destinations tend to choose streets of high Int.V. The choice of males is affected by Int.V, SHOPS, WIDTH (positive and CARS (negative. Females prefer streets that have many shops, and couples tend to choose downhill streets. The behavior of individual persons is affected by all variables. The behavior of people visiting in groups is affected by SHOP and WIDTH (positive.

  20. An Assessment of the Emerging Networks of Support for Street ...

    African Journals Online (AJOL)

    Nekky Umera

    by the homeless adults on the street is most preferred (μ=3.26) while the government .... Researchers over the years have explored how the problem of street children .... crisis you will be the first target because they will think that you have so.

  1. Formation of Periodic Vortex Streets Driven by the Lorents Force

    OpenAIRE

    池端, 義人; 本地, 弘之; 杉原, 裕司

    1996-01-01

    Quasi-2D periodic vortex streets, driven by the Lorentz force due to the interaction of a localized magnetic field with an electrolytic current, have been investigated experimentally using a shallow water tank with a movable bottom floor. The vortex street formation has also been investigated numerically and some simulated flow patterns are presented.

  2. Do urban canyons influence street level grass pollen concentrations?

    DEFF Research Database (Denmark)

    Peel, Robert George; Kennedy, Roy; Smith, Matt

    2014-01-01

    In epidemiological studies, outdoor exposure to pollen is typically estimated using rooftop monitoring station data, whilst exposure overwhelmingly occurs at street level. In this study the relationship between street level and roof level grass pollen concentrations was investigated for city cent...

  3. Road dust emission sources and assessment of street washing effect

    NARCIS (Netherlands)

    Karanasiou, A.; Amato, F.; Moreno, T.; Lumbreras, J.; Borge, R.; Linares, C.; Boldo, E.; Alastuey, A.; Querol, X.

    2014-01-01

    Although previous studies report on the effect of street washing on ambient particulate matter levels, there is a lack of studies investigating the results of street washing on the emission strength of road dust. A sampling campaign was conducted in Madrid urban area during July 2009 where road dust

  4. Politely Disregarded: Street Fiction, Mass Incarceration, and Critical Praxis

    Science.gov (United States)

    Van Orman, Karin; Lyiscott, Jamila

    2013-01-01

    Due to prevailing attitudes about the prison industrial complex and African American and Latino/Latina communities, the literary production of urban street fiction has been politely disregarded by our society. Through the use of critical praxis, utilizing urban street fiction in the classroom is a necessary and urgent act of social justice. Street…

  5. The Initiation of Homeless Youth into the Street Economy

    Science.gov (United States)

    Gwadz, Marya Viorst; Gostnell, Karla; Smolenski, Carol; Willis, Brian; Nish, David; Nolan, Theresa C.; Tharaken, Maya; Ritchie, Amanda S.

    2009-01-01

    Homeless youth (HY) who lack employment in the formal economy typically turn to the street economy (e.g., prostitution, drug selling) for survival. Guided by the theory of social control, the present paper explores factors influencing HY's initiation into the street economy. Eighty HY (ages 15-23) were recruited from four community-based…

  6. A Semiotic Reading and Discourse Analysis of Postmodern Street Performance

    Science.gov (United States)

    Lee, Mimi Miyoung; Chung, Sheng Kuan

    2009-01-01

    Postmodern street art operates under a set of references that requires art educators and researchers to adopt alternative analytical frameworks in order to understand its meanings. In this article, we describe social semiotics, critical discourse analysis, and postmodern street performance as well as the relevance of the former two in interpreting…

  7. Political Education--Occupy Wall Street's First Year

    Directory of Open Access Journals (Sweden)

    Jackie DiSalvo

    2013-05-01

    Full Text Available While Occupy Wall Street (OWS is easily identified with direct action in the streets, equal recognition should be given to the vast amount of political education that took place. This article will give an overview of that and briefly assess its emphases and absences.

  8. A Semiotic Reading and Discourse Analysis of Postmodern Street Performance

    Science.gov (United States)

    Lee, Mimi Miyoung; Chung, Sheng Kuan

    2009-01-01

    Postmodern street art operates under a set of references that requires art educators and researchers to adopt alternative analytical frameworks in order to understand its meanings. In this article, we describe social semiotics, critical discourse analysis, and postmodern street performance as well as the relevance of the former two in interpreting…

  9. Street mirrors, surveillance, and urban communities in early modern Finland

    NARCIS (Netherlands)

    Ylimaunu, T.; Symonds, J.; Mullins, P.R.; Salmi, A.-K.; Nurmi, R.; Kallio-Seppä, T.; Kuokkanen, T.; Tranberg, A.

    2014-01-01

    This article discusses street mirrors or ‘gossip mirrors’, in terms of urban social relations and surveillance. Street mirrors were introduced to coastal towns in Sweden and Finland in the 18th and early 19th centuries and may still be found in well-preserved towns with historic wooden centres. The

  10. The Initiation of Homeless Youth into the Street Economy

    Science.gov (United States)

    Gwadz, Marya Viorst; Gostnell, Karla; Smolenski, Carol; Willis, Brian; Nish, David; Nolan, Theresa C.; Tharaken, Maya; Ritchie, Amanda S.

    2009-01-01

    Homeless youth (HY) who lack employment in the formal economy typically turn to the street economy (e.g., prostitution, drug selling) for survival. Guided by the theory of social control, the present paper explores factors influencing HY's initiation into the street economy. Eighty HY (ages 15-23) were recruited from four community-based…

  11. INTRODUCTION The term street children has many definitions in ...

    African Journals Online (AJOL)

    supervision and street influence on them. These children also form a .... area of Nigeria: Drug and Alcohol Dependence. 2003; 00: 1-8. 6. A Civil ... Neighborhood: Street Children and the Public. Space.” Childhood ... for adolescents. Journal of ...

  12. Simulation of Pedestrians Crossing a Street

    CERN Document Server

    Boenisch, Cornelia

    2009-01-01

    The simulation of vehicular traffic as well as pedestrian dynamics meanwhile both have a decades long history. The success of this conference series, PED and others show that the interest in these topics is still strongly increasing. This contribution deals with a combination of both systems: pedestrians crossing a street. In a VISSIM simulation for varying demand jam sizes of vehicles as well as pedestrians and the travel times of the pedestrians are measured and compared. The study is considered as a study of VISSIM's con ict area functionality as such, as there is no empirical data available to use for calibration issues. Above a vehicle demand threshold the results show a non-monotonic dependence of pedestrians' travel time on pedestrian demand.

  13. The digital evolution of occupy wall street.

    Science.gov (United States)

    Conover, Michael D; Ferrara, Emilio; Menczer, Filippo; Flammini, Alessandro

    2013-01-01

    We examine the temporal evolution of digital communication activity relating to the American anti-capitalist movement Occupy Wall Street. Using a high-volume sample from the microblogging site Twitter, we investigate changes in Occupy participant engagement, interests, and social connectivity over a fifteen month period starting three months prior to the movement's first protest action. The results of this analysis indicate that, on Twitter, the Occupy movement tended to elicit participation from a set of highly interconnected users with pre-existing interests in domestic politics and foreign social movements. These users, while highly vocal in the months immediately following the birth of the movement, appear to have lost interest in Occupy related communication over the remainder of the study period.

  14. The Digital Evolution of Occupy Wall Street

    CERN Document Server

    Conover, Michael D; Menczer, Filippo; Flammini, Alessandro

    2013-01-01

    We examine the temporal evolution of digital communication activity relating to the American anti-capitalist movement Occupy Wall Street. Using a high-volume sample from the microblogging site Twitter, we investigate changes in Occupy participant engagement, interests, and social connectivity over a fifteen month period starting three months prior to the movement's first protest action. The results of this analysis indicate that, on Twitter, the Occupy movement tended to elicit participation from a set of highly interconnected users with pre-existing interests in domestic politics and foreign social movements. These users, while highly vocal in the months immediately following the birth of the movement, appear to have lost interest in Occupy related communication over the remainder of the study period.

  15. Workshop Murska Sobota, North of Lendavska Street

    Directory of Open Access Journals (Sweden)

    Mitja Zorc

    2012-01-01

    Full Text Available The urban design workshop "North of Lendavska Street" addressed the extensive area north of downtown Murska Sobota. The area is undergoing intensive transformation. Service and commercial programmes are occupying abandoned industrial and military facilities and filling the empty spaces between. Due to its location near the city centre and its proximity to natural surroundings across the Ledava stream, the area is also attractive for housing and recreation. The existing residential neighbourhood to the south has poor living conditions due to inadequate open space and a badly organised traffic system. The workshop, organised by the Municipality of Murska Sobota, involved groups of students from three Slovene faculties and two groups of practicing architects. The groups proposed designs and strategies for possible future urban development and formed a joint professional platform to prepare spatial planning documents.

  16. Do urban canyons influence street level grass pollen concentrations?

    DEFF Research Database (Denmark)

    Peel, Robert George; Kennedy, Roy; Smith, Matt

    2014-01-01

    In epidemiological studies, outdoor exposure to pollen is typically estimated using rooftop monitoring station data, whilst exposure overwhelmingly occurs at street level. In this study the relationship between street level and roof level grass pollen concentrations was investigated for city centre...... street canyon environments in Aarhus, Denmark, and London, UK, during the grass pollen seasons of 2010 and 2011 respectively. For the period mid-day to late evening, street level concentrations in both cities tended to be lower than roof-level concentrations, though this difference was found...... source distribution. In the London study, an increase in relative humidity was linked to a significant decrease in street/roof level concentration ratio, and a possible causative mechanism involving moisture mediated pollen grain buoyancy is proposed. Relationships with the other weather variables were...

  17. Asymmetric effects of cooler and warmer winters on beech phenology last beyond spring

    Science.gov (United States)

    Signarbieux, Constant; Toledano, Ester; Sangines, Paula; Fu, Yongshuo; Schlaepfer, Rodolphe; Buttler, Alexandre; Vitasse, Yann

    2017-04-01

    In temperate trees, the timing of plant growth onset and cessation affect biogeochemical cycles, water and energy balance. Currently, phenological studies largely focus on specific phenophases and on their responses to warming. How differently spring phenology responds to the warming and cooling, and affects the subsequent phases, has not been well investigated. Here, we exposed saplings of Fagus sylvatica L. to warmer and cooler climate during the winter 2013-2014 by conducting a reciprocal transplant experiment between two elevations (1340 vs. 371 m.a.s.l., ca. 6°C difference) in the Swiss Jura mountains. To test the legacy effects of earlier or later budburst on the budset timing, saplings were moved back to their original elevation shortly after the occurrence of budburst in spring 2014. One degree decrease of air temperature resulted in a delay of 10.9 days in budburst dates, whereas one degree of warming advanced the date by 8.8 days. Interestingly, we found an asymmetric effect of the warmer winter vs. cooler winter on the budset timing in autumn: saplings experiencing a cooler winter showed a delay of 31 days in their budset timing compared to the control, whereas saplings experiencing a warmer winter showed 10 days earlier budset. The dependency of spring over autumn phenophases might be partly explained by the building up of the non-structural carbohydrate storage and suggests that the potential delay in growth cessation due to global warming might be smaller than expected. We did not find a significant correlation in budburst dates between 2014 and 2015, indicating that the legacy effects of the different phenophases might be reset during each winter. Adapting phenological models to the whole annual phenological cycle, and considering the different response to cooling and warming, would improve predictions of tree phenology under future climate warming conditions.

  18. Operation of a pond-cooler: the case of Berezovskaya GRES-1

    Science.gov (United States)

    Morozova, O. G.; Kamoza, T. L.; Koyupchenko, I. N.; Savelyev, A. S.; Pen, R. Z.; Veselkova, N. S.; Kudryavtsev, M. D.

    2017-08-01

    Pond-coolers at heat and nuclear power stations are natural-technological systems, so the program of their monitoring should include the effect made by the SRPS (state regional power station) on the pond ecosystem, including thermal discharge of cooling water. The objectives of this study were development and implementation of a monitoring program for the cooling pond of Berezovskaya SRPS-1 on the chemical and biological water quality indicators and identification of patterns of the thermal and hydrochemical regime when operating the progressive power plant (from 1996 to 2015). The quality of the cooling water of the pond-cooler BGRES-1 was studied under full-scale conditions by selecting and analyzing the water samples of the pond in accordance with the principles of complexity, systematic observation, and consistency of timing their conduct with the characteristic hydrological phases. Processing of the obtained array of monitoring data by methods of mathematical statistics makes it possible to identify the main factors affecting the water quality of the pond. The data on water quality obtained during their monitoring and mathematical processing over a long time interval are the scientific basis for forecasting the ecological state of the pond, which is necessary to economically ensure the efficient energy production and safety of water use. Recommendations proposed by these authors, including those partially already implemented, have been to prevent the development of eutrophication processes in the pond-cooler: the construction of a dam that cuts off the main peat massif and cleaning the river banks forming the cooling pond.

  19. Exo-reversible staging of coolers in series and in parallel

    Science.gov (United States)

    Maytal, Ben-Zion

    2017-10-01

    Serial and parallel staging of exo-reversible coolers are formulated, analyzed and compared. The parallel staging includes an extensive parameter which is the proportion of combined stages. This extensive free parameter affects the intensive factors of specific power and figure of merit. Serial staging reduces the 1st Law efficiency and parallel staging improves the 2nd Law efficiency. Comparison of a parallel with a serial staging under common cooling capacity and cooling range, shows that it is always possible to find a parallel arrangement of lower specific power and more compact. Some results are demonstrated on staging of Joule-Thomson cryocoolers (below and above the Joule-Thomson inversion temperature).

  20. Laboratory Performance Of Evaporative Cooler Using Jute Fiber Ropes As Cooling Media

    OpenAIRE

    Kulkarni, R K; S.P.S. Rajput

    2014-01-01

    Evaporative coolers use a variety of cooling media like wood wool, cellulose, aspen. This paper analyses the performance of jute fiber ropes as alternative cooling media. They are capable of retaining high moisture and have a large wetted surface area. Hot and dry air is allowed to flow over the wet jute rope bank tightly held between two plates which are integral part of two tanks. The inlet conditions of air varied from 30.5 0C dry bulb temperature and 52 % relative humidity to ...

  1. Specification of a new electron cooler for the low energy ion accumulator ring, LEIR

    CERN Document Server

    Tranquille, Gerard

    2004-01-01

    For the cooling of Pb**5**4**+ ions in the future low-energy ion ring machine a new electron cooling device needs to be constructed. This new cooler will take advantage of all the recent developments in electron cooling in order to balance efficient and fast cooling with a sufficiently long ion beam lifetime for beam accumulation. This paper will present the special features of the device and how their combination will be used to obtain low emittance beams for transfer to the LHC.

  2. The heavy ion cooler-storage-ring project (HIRFL-CSR) at Lanzhou

    CERN Document Server

    Xia, J W; Wei, B W; Yuan, Y J; Song, M T; Zhang, W Z; Yang, X D; Yuan Ping; Gao, D Q; Zhao, H W; Yang, X T; Xiao, G Q; Man, K T; Dang, J R; Cai, X H; Wang, Y F; Tang, J Y; Qiao, W M; Rao, Y N; He, Y; Mao, L Z; Zhou, Z Z

    2002-01-01

    HIRFL-CSR, a new ion Cooler-Storage-Ring (CSR) project, is the post-acceleration system of the Heavy Ion Research Facility in Lanzhou (HIRFL). It consists of a main ring (CSRm) and an experimental ring (CSRe). From the HIRFL cyclotron system the heavy ions will be accumulated, cooled and accelerated in the CSRm, then extracted fast to produce radioactive ion beams (RIB) or highly charged heavy ions. Those secondary beams will be accepted and stored by the CSRe for many internal-target experiments with electron cooling.

  3. A radio frequency ring electrode cooler for low-energy ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Heinz, S. [Sekt. Phys., Ludwig-Maximilians-Universitaet, Am Coulombwall 1, Muenchen, D-85748 Garching (Germany)]. E-mail: sophie.heinz@physik.uni-muenchen.de; Aeystoe, J. [Department of Physics, University of Jyvaeskylae, P.O. Box 35 (Y5), FIN-40351 Jyvaeskylae (Finland); Habs, D. [Sekt. Phys., Ludwig-Maximilians-Universitaet, Am Coulombwall 1, Muenchen, D-85748 Garching (Germany); Hegewisch, S. [Sekt. Phys., Ludwig-Maximilians-Universitaet, Am Coulombwall 1, Muenchen, D-85748 Garching (Germany); Huikari, J. [Department of Physics, University of Jyvaeskylae, P.O. Box 35 (Y5), FIN-40351 Jyvaeskylae (Finland); Nieminen, A. [Department of Physics, University of Jyvaeskylae, P.O. Box 35 (Y5), FIN-40351 Jyvaeskylae (Finland); Rinta-Antila, S. [Department of Physics, University of Jyvaeskylae, P.O. Box 35 (Y5), FIN-40351 Jyvaeskylae (Finland); Schumann, M. [Sekt. Phys., Ludwig-Maximilians-Universitaet, Am Coulombwall 1, Muenchen, D-85748 Garching (Germany); Szerypo, J. [Sekt. Phys., Ludwig-Maximilians-Universitaet, Am Coulombwall 1, Muenchen, D-85748 Garching (Germany)

    2004-11-11

    We are investigating a new concept for ion confinement while buffer-gas-cooling low-energy ion beams. Instead of applying the well-established technique of Radio Frequency Quadrupoles (RFQs) where the ions are transversely confined by a quadratic-pseudo potential we are using a stack of thin ring electrodes supplied by an RF field (RF funnel) which creates a box-shaped potential well. In Monte Carlo simulations we have investigated the transmission behavior and cooling performance of the RF funnel. First experimental investigations with ion currents up to 20 nA revealed a promising transmission characteristic which qualifies the RF funnel as high-current cooler.

  4. Occupational Profile and Perceptions of Street Children in Surat City

    Directory of Open Access Journals (Sweden)

    Patel NB, Desai Toral, Bansal RK, Girish Thakar

    2011-01-01

    Full Text Available Street children constitute a highly vulnerable, most deprived and marginalized section of the society, whose rights are constantly violated with impunity. This study attempts to explore the occupational profile of the street children in the city of Surat and pertinent aspects thereof. This cross-sectional study was conducted by interviewing 326 street children in Surat city. The study revealed that majority of the street children (79.8% start earning money as beggars. They soon switch over to other petty jobs/ activities. The street children select their occupation according to their choice of work, availability of an opportunity and the amount of money available to them. Their occupational profile changes according to their age; the period of stay in Surat; and, the money available with them. The earnings of these children fluctuate with the season. Leading five occupation adopted by street children includes Working in eatables and tea stalls (11.7%; Begging and or sweeping (11.3%; Selling newspapers, magazines and books (11.3%; Shoe shining (9.8% and Selling drinking water bottles & pouches & cold drinks (9.5%. Shoe shining is mostly carried out by the boys aged more than 12 years. Commercial sex work by girls is considered as inevitable by street girls. Illicit alcohol transport and selling is most lucrative and is often attract street children in to this occupation. Some street children become pick pockets under the guidance of an older pick pocket. Usually children who are very young, have recently come into the streets and their original families are often the most disadvantaged are more likely to engage in Picking up rags work as this requires no capital, no contacts and very less labour.

  5. Distribution of selected PCB congeners in the Babcock Street sewer district: a multimedia approach to identify PCB sources in combined sewer overflows (CSOs) discharging to the Buffalo River, New York.

    Science.gov (United States)

    Loganathan, B G; Irvine, K N; Kannan, K; Pragatheeswaran, V; Sajwan, K S

    1997-08-01

    To evaluate sources of PCBs in combined sewer overflows (CSOs) to the Buffalo River, New York, combined sewage, sanitary flow, atmospheric wet and dry depositions, and street dust samples were collected from the Babcock Street sewer district and analyzed. Total PCB concentrations (sum of the PCB congeners quantitated) in particulate and dissolved phases of sanitary flow were 101-269 ng g-1 dry weight and 50% of the total PCB load in street dust samples. PCB congener composition in the particulate phase of CSOs reflects the congener pattern of the street dusts. In this context, it can be suggested that the local contaminated street dusts are one of the potential sources of PCBs in CSOs, which is a source of PCBs to the Buffalo River.

  6. Comparison of different UHI mitigation strategies: the street- versus roof-level implementation

    Science.gov (United States)

    Li, X.; Georgescu, M.; Norford, L. K.

    2015-12-01

    Many mitigation approaches have been proposed to ameliorate the deleterious aspects of urbalization on climate, with special focus on the notorious urban heat island (UHI) effect. Of these approaches, high reflectance roof (cool roof) and pavement (cool pavement) and green roof or greenery are most commonly used and widely studied. However, the debate regarding the better implementation of cool and green technology is still ongoing. In this study, numerical sensitivity tests are carried out to evaluate the mitigation effect of the cool and green implementations at the city scale. The effects of roof-level and street-level implementations are compared in the context of a tropical urban environment.

  7. WALLS OF CRISIS: STREET ART AND URBAN FABRIC IN CENTRAL ATHENS, 2000–2012

    Directory of Open Access Journals (Sweden)

    Panos Leventis

    2014-11-01

    Unavoidably, artists became ever more political as their work emerged on the urban and architectural corpses. A sense of the unknown, of ‘what next’, waited at the end of the painted walls. It can be concluded that Athenian street art, always within its specific constructed sites and context, functioned as both an anticipation and a reflection of the socio-urban conditions and developments of the years from 2008 to 2012, and it remains key to the interpretation and understanding of what a whole generation hopes and expects from its city through these quickly changing socio-urban times and landscapes.

  8. Theoretical Performance Analysis of Indirect-Direct Evaporative Cooler in Hot and Dry Climates

    Directory of Open Access Journals (Sweden)

    R.K.KULKARNI,

    2011-02-01

    Full Text Available This paper theoretically analyses the performance of indirect-direct two stage cooler in hot and dry climate of Bhopal, India. Indirect cooling stage consisting of plate type wet surface heat exchangerfollowed by direct cooling stage consisting of rigid cellulose and aspen fiber in rectangular, semicylindrical and semi-hexagonal shapes as cooling media is considered. Based on summer weather data ofBhopal, most frequently occurring condition of 39.9 0C DBT and 32.8 % RH is selected for the analysis. Indirect evaporative cooler effectiveness is estimated in the range of 0.95 to 0.82 for primary air flow rate of 0.3 to 1.25 kg/s. Saturation efficiency in the direct cooling mode is obtained in the range of 89.1 to 63.4 % and cooling capacity from 11472 to 52576 kJ/h for different combinations. In combined mode saturation efficiency is obtained between 121.5 and 106.7 % and cooling capacity between 18244 to 73809 kJ/h. The final outlet temperature of air in combined mode ranges between 22.5 0C and 24.6 0C.

  9. Study on turbulent flow and heat transfer performance of tubes with internal fins in EGR cooler

    Science.gov (United States)

    Liu, Lin; Ling, Xiang; Peng, Hao

    2015-01-01

    In this paper, flow and heat transfer performances of the tubes with internal longitudinal fins in Exhaust Gas Recirculation (EGR ) cooler were investigated by three-dimension computation and experiment . Each test tube was a single-pipe structure, without inner tube. Three-dimension computation was performed to determine the thermal characteristics difference between the two kinds of tubes, that is, the tube with an inner solid staff as a blocked structure and the tube without the blocked structure. The effects of fin width and fin height on heat transfer and flow are examined. For proving the validity of numerical method, the calculated results were compared with corresponding experimental data. The tube-side friction factor and heat transfer coefficient were examined. As a result, the maximum deviations between the numerical results and the experimental data are approximately 5.4 % for friction factor and 8.6 % for heat transfer coefficient, respectively. It is found that two types of internally finned tubes enhance significantly heat transfer. The heat transfer of the tube with blocked structure is better, while the pressure drop of the tube without blocked structure is lower. The comprehensive performance of the unblocked tube is better to applied in EGR cooler.

  10. The low-energy electron cooler for the Cryogenic Storage Ring

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, Stephen; Blaum, Klaus; Krantz, Claude; Wolf, Andreas [Max-Planck-Institut fuer Kernphysik, 69117 Heidelberg (Germany)

    2014-07-01

    The Cryogenic Storage Ring (CSR) at the Max Planck Institute for Nuclear Physics in Heidelberg, Germany, is being commissioned. CSR will be an ideal tool for preparing and studying cold atomic and molecular ions using ion beams of 20-300 keV kinetic energy (per ion charge unit). As a first important upgrade CSR will be equipped with an electron cooler. Latter is designed for cooling beams with a charge-to-mass ratio q/m of 1 to 1/160 e/aμ. This corresponds to an electron beam energy range of 1 to 163 eV. The beam will be produced by a cryogenic photocathode and electron temperatures in the co-moving frame reach down to 10 K. The cooler can also be used as an electron target by detuning the electrons' kinetic energy. This allows precision experiments on low-energy collisions between cold electrons and stored atomic and molecular ions using counting and imaging detectors. The design and the status of the setup are presented.

  11. Development of a new RFQ beam cooler and buncher for the CANREB project at TRIUMF

    Energy Technology Data Exchange (ETDEWEB)

    Barquest, B.R. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC V6T 2A3 (Canada); Bale, J.C.; Dilling, J. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC V6T 2A3 (Canada); UBC Department of Physics and Astronomy, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Gwinner, G. [University of Manitoba, Department of Physics and Astronomy, Allen Building, Winnipeg, MB R3T 2N2 (Canada); Kanungo, R. [Saint Mary’s University, Astronomy and Physics Department, 923 Robie Street, Halifax, NS B3H 3C3 (Canada); Krücken, R. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC V6T 2A3 (Canada); UBC Department of Physics and Astronomy, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Pearson, M.R. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC V6T 2A3 (Canada)

    2016-06-01

    A new radiofrequency quadrupole (RFQ) based ion beam cooler and buncher is under development for the CANadian Rare-isotope facility with Electron Beam ion source (CANREB) project at TRIUMF. The CANREB project requires an RFQ buncher that will efficiently accept continuous beams of rare isotopes from either the Advanced Rare IsotopE Laboratory (ARIEL) or Isotope Separator and ACcelerator (ISAC) target by way of a high resolution magnetic spectrometer, with energies up to 60 keV and deliver bunched beams to an electron beam ion source (EBIS) for charge breeding. The energy of the bunched beam delivered to the EBIS will be adjustable to match the requirements of the existing post acceleration infrastructure. The CANREB RFQ incorporates design considerations to facilitate ease of use over a wide range of ion masses, and is intended to accommodate incident beam rates as high as 10{sup 8} pps, delivering beam bunches at 100 Hz. An overview of the CANREB RFQ design concept will be presented, informed by results from both ion optical simulations as well as commissioning efforts with other beam cooler and buncher devices. Simulation results indicate that the design is well suited to deliver high quality bunched beams with high efficiency with as many as 10{sup 6} ions per bunch.

  12. HEAT PUMP GAS COOLER CONTROL USING CRITERION OF MINIMUM OF EXERGY LOSSSES

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2014-08-01

    Full Text Available This paper focuses on the development of the criterion of optimality of transients of the control system, based on the minimum of exergy losses in the gas cooler of carbon dioxide heat pump. It is noted that the exergy quality criterion has a clear physical meaning, as compared with the integral quadratic criterion in which the choice of the coefficients in the integrand is not justified. Mathematic model of heat exchanger is obtained using the method of solving differential equations, without going to the irrational transfer functions. The model is reduced to transfer functions of the first and second order with the delay. The continuous temperature control system of heat pump gas cooler is considered. It is shown, that one of the versions of the control system for the minimization of the proposed criterion can be a combined control system using both the principle of the negative feedback and the principle of the invariance related to a number of disturbances affecting the processes of heat transfer in the heat exchanger.

  13. Laboratory Performance Of Evaporative Cooler Using Jute Fiber Ropes As Cooling Media

    Directory of Open Access Journals (Sweden)

    R.K.Kulkarni

    2014-12-01

    Full Text Available Evaporative coolers use a variety of cooling media like wood wool, cellulose, aspen. This paper analyses the performance of jute fiber ropes as alternative cooling media. They are capable of retaining high moisture and have a large wetted surface area. Hot and dry air is allowed to flow over the wet jute rope bank tightly held between two plates which are integral part of two tanks. The inlet conditions of air varied from 30.5 0C dry bulb temperature and 52 % relative humidity to 34.5 0C dry bulb temperature and 32 % relative humidity. Outlet temperature of air is measured and saturation efficiency and cooling capacity are calculated. The outlet dry bulb temperature is obtained between 25.8 0C and 26.2 0C.The saturation efficiencies range from 69 % to 59 % and the cooling capacity is obtained between 6173 kJ/h and 11979 kJ/h. Thus jute fiber ropes prove to be a good alternative cooling media in evaporative cooler

  14. P-type InGaAsP coolers for integrated optic devices

    Science.gov (United States)

    Vashaee, Daryoosh; LaBounty, Christopher J.; Fang, Xiaofeng; Zeng, Gehong; Abraham, Patrick; Bowers, John E.; Shakouri, Ali

    2001-05-01

    Single stage thin film coolers based on thermoelectric and thermionic cooling in p-type InGaAsP superlattice structures have been fabricated. Devices with different sizes and at various ambient temperatures have been characterized. Experimental results showed 0.5 degree centigrade cooling below the ambient temperature at 25C. This cooling over 1 4mu2m thick superlattice barrier corresponds to cooling power densities on the order of 200 W/cm2. The device cools by a factor of two better at higher temperatures (70C). This is due to the reduction of the superlattice thermal conductivity and the broadening of the electronic distribution function at higher temperatures. 150x150 micrometers 2 devices provide largest cooling at room temperature while the optimum device size shrinks as the temperature increases. Simulations results that take into account finite thermal resistance of the InP substrate, the effect of the contact resistance, heat generation in the wire-bonds and metallic pads on top of the device predict accurately the optimum cooling of these micro refrigerators. By eliminating the major parasitic sources of heating (Joule heating in the substrate, heat conduction through the side contact and reducing the contact resistance to 5x7-7 ohm-cm2) simulations show that, ultimately, one can achieve 15 degree(s)C cooling (10's of kW/cm2 cooling power) with single stage p-InGaAsP thin film coolers.

  15. Smoking Behaviors of Street Children in Makassar 2013

    Directory of Open Access Journals (Sweden)

    Ridwan Amiruddin

    2015-08-01

    Full Text Available Street children are vulnerable groups of risky behavior like smoking behavior. This study aims to describe smoking and relation with education, living with parents, family, peer influence, and religiosity. Study design was cross sectional study. The population was 990 street children with the sample of 277 street children. Sample selection in accidental sampling with criteria of respondents aged 10-19 years and Muslims. Data were analyzed with chi square test with confidence interval of 95% (α=0.05. Results show that 48% of street children have ever smoked and 37.2% of street children were still smoking in the last 30 days. Then, there is a relationship between living with parents (p=0.002 and levels of religiosity (p=0.023. However, there was no relationship with school status (p=0613, family history (p=0.874, and peer influence (p=0.157 with the smoking behavior of street children. This research suggests to give education about the dangers of smoking, provide religious values for them and involve them in religious social activities, family empowerment approach to parents to guide their children not to smoke, and optimize function of NGOs or shelters for street children.

  16. Resuspension of particulate matter and PAHs from street dust

    Science.gov (United States)

    Martuzevicius, D.; Kliucininkas, L.; Prasauskas, T.; Krugly, E.; Kauneliene, V.; Strandberg, B.

    2011-01-01

    Winter street sanding activities in northern countries are often associated with elevated pollution by particulate matter. There are indications that street dust may act as a source of particle-bound PAHs. However, very few studies have addressed the resuspension potential of PAHs from street dust. The purpose of this study was to quantitatively assess emissions of particulate matter and PAHs from street dust by laboratory-scale simulation of particle resuspension. Increases in air velocity caused proportional increases in air-borne PM 2.5, PM 10 and PM total concentrations, while the concentrations of PAHs associated with resuspended particles did not show clear statistically significant dependence on air velocity. A substantial difference in particle and PAH resuspension was observed between dust from the city center street and dust from the connecting street. The data obtained in the present study indicate that street dust may be a significant source not only of PMs but also of particle-bound PAHs in ambient air.

  17. Improving the Efficiency of the Heat Pump Control System of Carbon Dioxide Heat Pump with Several Evaporators and Gas Coolers

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2016-12-01

    Full Text Available The problem of coordination of the values of the refrigerant flow through the evaporators and gas coolers of the heat pump for the simultaneous production of heat and cold is studied. The compensation of the variations of the total flow through the evaporators is implemented using the variation of the capacity of the compressor and a corresponding change in flow through the auxiliary gas cooler of the heat pump. Control system of this gas cooler is constructed using the invariance principle of the output value (outlet temperature of the heated agent with respect to perturbations on the control channel (the refrigerant flow through the gas cooler. Principle of dual-channel compensation of the disturbance and advancing signal on input of control valve of the refrigerant through the gas cooler is ensured. Due to proposed solution, the intensity of the disturbances on the flow of refrigerant is reduced. Due to proposed technical solution power consumed by the heat pump compressor drive under transients is decreased.

  18. Quantifying Reflection

    DEFF Research Database (Denmark)

    Alcock, Gordon Lindsay

    2013-01-01

    This paper documents 1st semester student reflections on “learning to learn” in a team-based PBL environment with quantitative and qualitative student reflective feedback on the learning gains of 60 Architectural Technology and Construction Management students at VIA University College, Denmark....... It contrasts the students’ self-assessment in a range of ‘product’ skills such as Revit, Structural Design, Mathematics of construction, Technical Installations; as well as ‘process’ competencies such as ‘Working in a team’, Sharing knowledge, Maintaining a portfolio and Reflecting ON learning and FOR learning......´ These are all based on Blooms taxonomy and levels of competence and form a major part of individual student and group learning portfolios. Key Words :Project-Based learning, Reflective Portfolios, Self assessment, Defining learning gains, Developing learning strategies , Reflections on and for learning...

  19. Associations between street connectivity and active transportation

    Directory of Open Access Journals (Sweden)

    Pickle Linda W

    2010-04-01

    Full Text Available Abstract Background Past studies of associations between measures of the built environment, particularly street connectivity, and active transportation (AT or leisure walking/bicycling have largely failed to account for spatial autocorrelation of connectivity variables and have seldom examined both the propensity for AT and its duration in a coherent fashion. Such efforts could improve our understanding of the spatial and behavioral aspects of AT. We analyzed spatially identified data from Los Angeles and San Diego Counties collected as part of the 2001 California Health Interview Survey. Results Principal components analysis indicated that ~85% of the variance in nine measures of street connectivity are accounted for by two components representing buffers with short blocks and dense nodes (PRIN1 or buffers with longer blocks that still maintain a grid like structure (PRIN2. PRIN1 and PRIN2 were positively associated with active transportation (AT after adjustment for diverse demographic and health related variables. Propensity and duration of AT were correlated in both Los Angeles (r = 0.14 and San Diego (r = 0.49 at the zip code level. Multivariate analysis could account for the correlation between the two outcomes. After controlling for demography, measures of the built environment and other factors, no spatial autocorrelation remained for propensity to report AT (i.e., report of AT appeared to be independent among neighborhood residents. However, very localized correlation was evident in duration of AT, particularly in San Diego, where the variance of duration, after accounting for spatial autocorrelation, was 5% smaller within small neighborhoods (~0.01 square latitude/longitude degrees = 0.6 mile diameter compared to within larger zip code areas. Thus a finer spatial scale of analysis seems to be more appropriate for explaining variation in connectivity and AT. Conclusions Joint analysis of the propensity and duration of AT behavior and an

  20. A Solution for Street Lighting in Smart Cities

    Directory of Open Access Journals (Sweden)

    M. Popa

    2012-06-01

    Full Text Available Smart Cities is a domain of great interest in the modern society. The aim of a smart urban environment is to increase citizens’ comfort and quality of life with minimum resources and power consumption and without affecting the natural environment. Street lighting is one of the main interests in such a smart environment. This thesis focuses on implementing a lighting control system that makes street lighting to be an autonomous and efficient part of the urban environment. The performance of the proposed system is analyzed using an OMNET++ network simulation. The results lead to the conclusion that the smart control system improves some drawbacks of a classic street lighting system.

  1. Studi Numerik Peningkatan Cooling Performance pada Lube Oil Cooler Gas Turbine yang Disusun Secara Seri dan Paralel dengan Variasi Kapasitas Aliran Lube Oil

    Directory of Open Access Journals (Sweden)

    Annis Khoiri Wibowo

    2014-09-01

    Full Text Available Salah satu komponen pada gas turbine adalah lube oil cooler yang berfungsi sebagai heat exchanger untuk mendinginkan temperatur lube oil. Pemasangan tiga lube oil cooler type-Z compact heat exchanger pada susunan seri dan paralel berdampak pada cooling capacity lube oil cooler. Uniformity flow rate pada masing-masing tube merupakan salah satu faktor yang mempengaruhi cooling capacity dari lube oil coole. Oleh karena itu dilakukan simulasi Computational Fluid Dynamic (CFD untuk mengkaji pengaruh pemasangan susunan tiga lube oil cooler secara seri dan paralel dengan variasi kapasitas lube oil terhadap performance lube oil cooler. Pemodelan domain dilakukan dengan 3 dimensi pada sisi eksternal dan internal. Simulasi pada sisi eksternal dilakukan untuk memperoleh nilai koefisien heat transfer pada masing-masing baris tube. Selanjutnya, nilai koefisien heat transfer yang didapat pada sisi eksternal digunakan sebagai kondisi batas wall convection pada masing-masing baris tube untuk simulasi internal flow dengan variasi flow rate lube oil 30 gpm, 50 gpm, 74 gpm. Dari hasil simulasi, susunan cooler seri menghasilkan cooling capacity yang lebih baik dari pada susunan cooler paralel pada kapasitas lube oil yang sama. Hal tersebut terjadi karena flow ratio lube oil untuk masing-masing tube pada susunan cooler seri lebih seragam dari pada susunan cooler paralel. Keseragaman flow rate pada masing-masing tube ditunjukkan dengan kecilnya standard deviasi flow ratio. Kapasitas 50 gpm memiliki standard deviasi flow ratio sebesar 0,46 untuk susunan seri dan 0,75 untuk susunan paralel. Semakin besar kapasitas lube oil maka distribusi flow rate pada masing-masing tube semakin tidak seragam. Selain itu susunan cooler seri memiliki pressure drop yang lebih besar dari pada susunan cooler paralel. Pemasangan susunan cooler dengan kapasitas 30 gpm memiliki tingkat keseragaman yang paling tinggi ditunjukkan dengan standard deviasi flow ratio pada masing-masing tube yang

  2. Street canyon ventilation control by proper planning and development

    Directory of Open Access Journals (Sweden)

    Balakin Vladimir Vasil'evich

    2014-05-01

    Full Text Available The objective of street canyon ventilation control in major streets is a tool of air pollution prevention in them, protection of housing areas from excessive wind or preservation and intensification of existing wind speed in case of insufficient ventilation. The maximum permissible concentration of car exhaust pollutants with wind speed within comfortable and permissible values by physiological and hygienic criteria, are ensured as from 40 to 70 % of thoroughfares in major cities. The dependence of air pollution level on wind speed is comparable to its dependence on traffic intensity and ratio of buildings height (H to street width. But one has to take into account that, if the wind blows across the street, vortices form within the street canyon, which results in higher concentration of car exhaust pollutants near the downwind buildings. The objective of this work is to find the functional dependences of wind speed in a major street on its width and density of buildings, and also to find out which street configurations are favorable for formation of closed air circulation within it, resulting in insufficient aeration. The experimental research was done on a site for large-scale modeling of built-up urban territory, using cup anemometers. The coefficients of dependence of wind speed within a street on the types of buildings and on the street width were obtained. Characteristics of street layouts for control of aeration were determined. Building density rates for maximizing or optimizing the wind speed were determined. Street layouts are considered where stable vortices form between the buildings. For example, vortices within the street canyon’s cross-section appear when buildings squarish in ground plan situated far apart are replaced by oblong ones with the minimum allowed intervals of 15 meters between them (for 5-storeyed buildings; or intervals equal to the buildings’ height, or where the buildings are long and close together. With

  3. Reflection ciphers

    DEFF Research Database (Denmark)

    Boura, Christina; Canteaut, Anne; Knudsen, Lars Ramkilde

    2017-01-01

    study the necessary properties for this coupling permutation. Special care has to be taken of some related-key distinguishers since, in the context of reflection ciphers, they may provide attacks in the single-key setting.We then derive some criteria for constructing secure reflection ciphers...... and analyze the security properties of different families of coupling permutations. Finally, we concentrate on the case of reflection block ciphers and, as an illustration, we provide concrete examples of key schedules corresponding to several coupling permutations, which lead to new variants of the block...

  4. Analyses of large scale tests addressing the performance of a containment cooler and its effect on gas distribution

    Energy Technology Data Exchange (ETDEWEB)

    Andreani, M.; Mignot, G. [Paul Scherrer Inst., Villigen (Switzerland)

    2011-07-01

    The performance of containment coolers and their effect on the hydrogen risk in the case of an accident with core overheat is an issue that needs to be addressed by means of simulation tools. Four tests performed in the PANDA facility within the OECD SETH 2 project provide a new database to evaluate the capability of the codes to predict the cooling effectiveness of a cooler and its effect on flow patterns and light gas distribution. All tests have been simulated with the GOTHIC code using a three-dimensional mesh and a rather detailed model for the cooler tube bundle. In general, the results obtained are in reasonable agreement with the data, although some major discrepancies have also been observed, which are mostly due to the limited detail permitted by the relatively coarse mesh adopted for all tests of the SETH 2 project. (author)

  5. 电机空冷器制造工艺改进%Manufacturing Process Improvements of Motor Air Cooler

    Institute of Scientific and Technical Information of China (English)

    谢常春; 苏启明; 梁子慧

    2013-01-01

    通过对空冷器制造工艺的改进,解决了空冷器因易变形而装配困难的问题.设计的钻模工装结构简单、定位准确,缩短了产品制造周期.与传统工艺相比优越性显著,对同类空冷器的加工制造,在工艺方法上值得借鉴和推广.%Through the improvement of motor air cooler manufacturing process,the air cooler assembly problem because of easy deformation was solved.The design of jig fixture structure was simple,accurate,and the product manufacturing cycle was shorted.Compared with the traditional process,the process method is worth reference and promotion similar to the processing and manufacturing of air cooler.

  6. On the Use of Thermoelectric (TE) Applications Based on Commercial Modules: The Case of TE Generator and TE Cooler

    Science.gov (United States)

    Zorbas, K.; Hatzikraniotis, E.; Paraskevopoulos, K. M.; Kyratsi, Th.

    2010-01-01

    In recent years, thermoelectricity sees rapidly increasing usages in applications like portable refrigerators, beverage coolers, electronic component coolers etc. when used as Thermoelectric Cooler (TEC), and Thermoelectric Generators (TEG) which make use of the Seebeck effect in semiconductors for the direct conversion of heat into electrical energy and is of particular interest for systems of highest reliability or for waste heat recovery. In this work, we examine the performance of commercially available TEC and TEG. A prototype TEC-refrigerator has been designed, modeled and constructed for in-car applications. Additionally, a TEG was made, in order to measure the gained power and efficiency. Furthermore, a TEG module was tested on a small size car (Toyota Starlet, 1300 cc), in order to measure the gained power and efficiency for various engine loads. With the use of a modeling approach, we evaluated the thermal contact resistances and their influence on the final device efficiency.

  7. Numerical Simulation on Flow and Heat Transfer Performance of Air-cooler for a Natural Gas Storage Compressor Unit

    Science.gov (United States)

    Liu, Biyuan; Zhang, Feng; Ma, Zenghui; Zheng, Zilong; Feng, Jianmei

    2017-08-01

    Heat transfer efficiency has been a key issue for large size air coolers with the noise reducers used in natural gas storage compressor unit, especially operated in summer with cooling air at a high temperature. The 3-D numerical simulation model of the whole air cooler was established to study the flow field characteristic with different inlet and outlet structures by CFD software. The system pressure loss distributions were calculated. The relationship was obtained among heat exchange efficiency, resistance loss, and the structure of air cooler, the results presented some methods to improve cooling air flow rate and heat exchange efficiency. Based on the results, some effective measures were proposed to improve heat exchanger efficiency and were implemented in the actual operation unit.

  8. Novel concept for driving the linear compressor of a micro-miniature split Stirling cryogenic cooler

    Science.gov (United States)

    Maron, V.; Veprik, A.; Finkelstein, L.; Vilenchik, H.; Ziv, I.; Pundak, N.

    2009-05-01

    New methods of carrying out homeland security and antiterrorist operations call for the development of a new generation of mechanically cooled, portable, battery powered infrared imagers, relying on micro-miniature Stirling cryogenic coolers of rotary or linear types. Since split Stirling linearly driven micro-miniature cryogenic coolers have inherently longer life spans, low vibration export and better aural stealth as compared to their rotary driven rivals, they are more suitable for the above applications. The performance of such cryogenic coolers depends strongly on the efficacy of their electronic drivers. In a traditional approach, the PWM power electronics produce the fixed frequency tonal driving voltage/current, the magnitude of which is modulated via a PID control law so as to maintain the desired focal plane array temperature. The disadvantage of such drivers is that they draw high ripple current from the system's power bus. This results in the need for an oversized DC power supply (battery packs) and power electronic components, low efficiency due to excessive conductive losses and high residual electromagnetic interference which in turn degrades the performance of other systems connected to the same power bus. Without either an active line filter or large and heavy passive filtering, other electronics can not be powered from the same power bus, unless they incorporate heavy filtering at their inputs. The authors present the results of a feasibility study towards developing a novel "pumping" driver consuming essentially constant instant battery power/current without making use of an active or passive filter. In the tested setup, the driver relies on a bidirectional controllable bridge, invertible with the driving frequency, and a fast regulated DC/DC converter which maintains a constant level of current consumed from the DC power supply and thus operates in input current control mode. From the experimental results, the steady-state power consumed by the

  9. An Assessment of the Emerging Networks of Support for Street ...

    African Journals Online (AJOL)

    An Assessment of the Emerging Networks of Support for Street Children in Nigeria. ... which these support networks are fulfilling their mission mandates is not yet known. Hence, this paper attempts to bridge ... Article Metrics. Metrics Loading .

  10. Analysis of Carol's Paradoxical Characters in Main Street

    Institute of Scientific and Technical Information of China (English)

    赵红璐; 高冰

    2010-01-01

    @@ 1. Introduction to Sinclair Lewis and Main Street Sinclair Lewis (1885-1951) is regarded as one of the foremost American satirists in the early twentieth century. He cared for books more than sports and felt limited by his rural hometown. In 1925, he rejected the Pulitzer Prize for Arrowsmith because he felt that he deserved the prize for Main Street. In 1930, he became the first American who won the Nobel Prize for Literature. Lewis was a novelist who was interested in many different aspects of American society, from business and medicine to small town life. His works were famous for insightful and critical views of the society and capitalist values. Lewis' s Main Street is considered to be his first success and his favorite work which is written in a dark tone. Main Street was published in 1920, which became a runaway bestseller.

  11. 'Unrecognized victims': Sexual abuse against male street children in ...

    African Journals Online (AJOL)

    Bernt Lindtjorn

    causes and effects of sexual abuse against male children and to what extent ... The second set of instruments consists of structured .... On the other hand, 37% explained that they do ..... most of the street boys chew khat, smoke cigarettes and.

  12. Reproductive health behaviour of street youth and associated ...

    African Journals Online (AJOL)

    McRoy

    More than half of the world's population is ... reproductive health consequences. ... assess reproductive health behaviour and needs of street youth in Gondar ..... decision. The participants in the two focus group discussions reported that the ...

  13. The vortex street as a statistical-mechanical phenomenon

    Science.gov (United States)

    Montgomery, D.

    1974-01-01

    An explanation of the Karman vortex street is presented on the basis of the two-temperature canonical distribution for inviscid two-dimensional flows in Navier-Stokes fluids or guiding-center plasmas.

  14. On Creativity and Humor: An Analysis of EASY STREET

    Science.gov (United States)

    Behrens, Roy R.

    1974-01-01

    Author attempted to present a reasonable description of the film, Easy Street, with major antics numbered, then analyzed those in terms of Duncker and Koestler, thereby extending the latter's theory of bisociation. (Author/RK)

  15. Doing Street Art in Backyards and Vacant Sites

    Directory of Open Access Journals (Sweden)

    Emma Paulsson

    2014-05-01

    Full Text Available When working illegally, graffiti writers and street artists are often working during nights and early mornings. During those hours, most people are inside, asleep, and the darkness also makes it easier for the artists to remain unseen.

  16. Finned tubes decide performance. A closer look at water coolers. Wasserkuehlsaetze unter der Lupe: Auf die Rippenrohre kommt es an

    Energy Technology Data Exchange (ETDEWEB)

    Menze, K.W.; Webb, R.L.; Apparao, T. (Pennsylvania State Univ., University Park (USA))

    1989-05-01

    The performance of standard and high-efficiency finned tubes in 800 kW water coolers was compared experimentally. Details are given of the dual-flow evaporators of the two R11 water coolers with 170 tubes each, the corrugated inner surface of the finned tube, the experimental facility, and the data acquisition system. After three years (9000 hours) of trial operation, it can be stated that the heat transfer was raised by an average 60% inside the condenser and by 40% inside the evaporator. Electricity savings amounted to about 13%. The amortisation period (replacement of standard tubes by high-efficiency tubes) is about 2 years. (HWJ).

  17. Numerical study on transverse asymmetry in the temperature profile of a regenerator in a pulse tube cooler

    DEFF Research Database (Denmark)

    Andersen, Stig Kildegård; Dietrich, M.; Carlsen, Henrik

    2007-01-01

    Transverse asymmetry in the temperature profile of the regenerator in a Stirling-type pulse tube cooler as observed in experiments was analysed in a numerical study. The asymmetry was reproduced using a one-dimensional model of the cooler where the regenerator was modelled using two identical...... parallel regenerator channels. The asymmetry was caused by a circulating flow that was superimposed on the oscillating flow. The primary mechanism driving the circulating flow was due to the wave form of the pressure difference between the ends of the regenerator and the dependence of the instantaneous...

  18. Numerical study on transverse asymmetry in the temperature profile of a regenerator in a pulse tube cooler

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Stig Kildegaard; Carlsen, Henrik [Department of Mechanical Engineering, Energy Engineering Section, Technical University of Denmark, Kgs. Lyngby (Denmark); Dietrich, Marc; Thummes, Guenter [Institute of Applied Physics, University of Giessen, D-35392 Giessen (Germany)

    2007-07-15

    Transverse asymmetry in the temperature profile of the regenerator in a Stirling-type pulse tube cooler as observed in experiments was analysed in a numerical study. The asymmetry was reproduced using a one-dimensional model of the cooler where the regenerator was modelled using two identical parallel regenerator channels. The asymmetry was caused by a circulating flow that was superimposed on the oscillating flow. The primary mechanism driving the circulating flow was due to the wave form of the pressure difference between the ends of the regenerator and the dependence of the instantaneous mass flow rate on the pressure difference and temperature. (author)

  19. A Simplified Simulation Model for Predicting Radiative Transfer in Long Street Canyons under High Solar Radiation Conditions

    Directory of Open Access Journals (Sweden)

    Carlos Rubio-Bellido

    2015-12-01

    Full Text Available Modeling solar radiation in street canyons is crucial to understanding the solar availability of building façades. This article describes the implementation of a simulation routine, developed in the Matlab® computer language, which is aimed at predicting solar access for building façades located in dense urban conglomerates comprising deep long street canyons, under high solar radiation conditions, typical in southern countries of Europe. Methodology is primarily based on the configuration factor theory, also aided by computer simulation, which enables to assess the interplay between the surfaces that compose the so-called street canyon. The results of the theoretical model have been cross-checked and verified by on-site measurements in two real case studies, two streets in Cadiz and Seville. The simplified simulation reproduces the shape of the curve for on-site measured values and weighted errors for the whole model do not surpass 10%, with a maximum of 9.32% and a mean values of 6.31%. As a result, a simplified predictive model that takes into account direct, diffuse and reflected solar radiation from the surfaces that enclose the canyon, has been devised. The authors consider that this research provides further improvement, as well as a handy alternative approach, to usual methods used for the calculation of available solar radiation in urban canyons, such as the Sky View Factor or the ray tracing.

  20. High-street fashion brand communication amongst female adolescents

    OpenAIRE

    Methanuntakul, Kanwipa

    2010-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. The nature of high-street fashion brands amongst female adolescents is a combined set of fast fashion movements and early adopter demands within a compressed timeframe. This research has investigated the need for a communication plan to appropriately deliver the brand message for this sector. There are a number of information barriers for high-street fashion brands to build customer value and...

  1. The Eldridge Street Synagogue, a Site of American Jewish Memory

    OpenAIRE

    Galith Touati

    2007-01-01

    (Special thanks to Jonathan Matz for the translation) Located at Eldridge Street 12, in Lower Manhattan, the Eldridge Street Synagogue (ESS) stands boldly amidst the brouhaha of what is today Chinatown as cars entering the Brooklyn Bridge whith by. This vast building is unique for several reasons. Its Moorish facade dominates the neighbouring tenements, and the building’s majesty is all the more powerful considering the nearly total disappearance of the quarter’s former Jewish identity. The s...

  2. Restoring Detroit's Street Lighting System

    Energy Technology Data Exchange (ETDEWEB)

    Kinzey, Bruce [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-09-30

    The City of Detroit is in the midst of a comprehensive restoration of its street lighting system that includes transitioning the existing HPS sources to LED. This report provides an objective review of the circumstances surrounding the system restoration, the processes undertaken and decisions made, and the results so far — and contains useful information about issues that arise during large-scale LED street lighting projects.

  3. Storying the street: transition narratives of homeless youth.

    Science.gov (United States)

    Ottaway, N; King, K; Erickson, P G

    2009-06-01

    Toronto Youth Street Stories is an innovative, web-based storytelling project that was conducted with homeless youths in Toronto. As a collaborative knowledge dissemination initiative, the project engaged youthful participants, authors, community mentors, youth service agencies and university-based researchers. Over 50 youths were encouraged to express their personal perspectives through author-led, creative writing workshops, resulting in youth-created stories, poems and pictures about a wide array of feelings and experiences. Across the dozens of pieces of writing, there is evidence of a chronology of street life, or an "arc of experience", that ranges from living with abuse and despair, leaving home, living on the street, experiencing a crisis or turning point, accessing services and gradually moving away from street life toward self-sustaining independence and security. This arc of experience includes the stories of youth who have transitioned away from the street as well as those still facing homelessness. This paper describes this arc of experience and illustrates it with the subjective material generated by the youths' stories about their lives on the streets of Toronto. We conclude that this project provided an important, creative outlet for the youths, and increased understanding of the challenges, stigma and resilience of homeless youth.

  4. Drug use among street children and adolescents: what helps?

    Directory of Open Access Journals (Sweden)

    Yone Gonçalves de Moura

    Full Text Available The aim of this study was to investigate factors associated to frequent and heavy drug use among street children and adolescents aged 10 to 18 years. A sample of 2,807 street children and adolescents from the 27 Brazilian state capital cities was analyzed. A World Health Organization questionnaire for non-students was adapted for use in Brazil. Data analysis was performed using logistic regression and decision tree models. Factors inversely associated with frequent and heavy drug use were: being age nine to 11 years (OR = 0.1; school attendance (OR = 0.3; daily time (one to five hours spent on the streets (OR = 0.3 and 0.4; not sleeping on the streets (OR = 0.4; being on the streets for less than one year (OR = 0.4; maintenance of some family bonds (OR = 0.5; presence on the streets of a family member (OR = 0.6; not suffering domestic violence (OR = 0.6; being female (OR = 0.8. All of these variables were significant at the p < 0.05 level. The findings suggest that being younger, having family bonds and engagement in school are important protective factors that affect drug use among this population and should be considered in the formulation of public policies.

  5. Effect of transverse electron velocities on the longitudinal cooling force in the Fermilab electron cooler

    CERN Document Server

    Khilkevich, Andrei; Shemyakin, Alexander V

    2012-01-01

    In Fermilab's electron cooler, a 0.1A, 4.3MeV DC electron beam propagates through the 20 m cooling section, which is immersed in a weak longitudinal magnetic field. A proper adjustment of 200 dipole coils, installed in the cooling section for correction of the magnetic field imperfections, can create a helix-like trajectory with the wavelength of 1-10 m. The longitudinal cooling force is measured in the presence of such helixes at different wavelengths and amplitudes. The results are compared with a model calculating the cooling force as a sum of collisions with small impact parameters, where the helical nature of the coherent angle is ignored, and far collisions, where the effect of the coherent motion is neglected. A qualitative agreement is found.

  6. Forced circulation air coolers with internally finned tubes; Ventilator-Luftkuehler mit innenberippten Rohren

    Energy Technology Data Exchange (ETDEWEB)

    Arnemann, M. [Forschungszentrum fuer Kaelte- und Umwelttechnik GmbH (FKU), Berlin (Germany)

    1998-04-01

    Tubes with internal fins have a much higher heat transfer during evaporation as compared with unfinned tubes. The findings served as a basis for the new development of the ``FHV high-performance forced circulation air cooler`` by Walter Roller GmbH and Co. The new evaporator type was designed on the basis of DIN 8955 and ENV 328 for evaporation temperatures of 0 C to -31 C. (orig.) [Deutsch] Im Vergleich zu glatten Rohren laesst sich durch den Einsatz von innenberippten Rohren der innere Waermeuebergang bei der Verdampfung nachweislich deutlich verbessern. Die Ergebnisse bildeten die Grundlage fuer die Neuentwicklung `FHV Hochleistungs-Luftkuehler` im Hause Walter Roller GmbH and Co. Die energetische Bewertung des neuen Verdampfertyps erfolgte in Anlehnung an die Normen DIN 8955 bzw. ENV 328 fuer Verdampfungstemperaturen zwischen 0 C und -31 C. (orig.)

  7. Predicting the nonsteady-state temperature conditions in water reservoirs/coolers

    Energy Technology Data Exchange (ETDEWEB)

    Nikitin, I.K.; Domanov, V.N.; Kostin, A.G.; Zhadan, V.I.

    1981-01-01

    A method is proposed for computing the cooling capacity of water reservoirs/coolers operating in non-steady-state weather conditions and thermal loads. The method is based on solving, in finite differences, nonsteady-state thermal balance equations written for the water reservoir as a whole. The influence of the wind velocity over the water reservoir and a number of other factors are accounted for in the computations on the thermal heat exchange from the surface of the water reservoirs. The reliability of the method is confirmed by comparing the computations to data from full-scale observations. Computations of the nonsteady state conditions in extremum periods make it possible to determine the maximum peak values for the temperature of the cooling water.

  8. Study on a cascade pulse tube cooler with energy recovery: new method for approaching Carnot

    Science.gov (United States)

    Wang, L. Y.; Wu, M.; Zhu, J. K.; Jin, Z. Y.; Sun, X.; Gan, Z. H.

    2015-12-01

    A pulse tube cryocooler (PTC) can not achieve Carnot efficiency because the expansion work must be dissipated at the warm end of the pulse tube. How to recover this amount of dissipated work is a key for improving the PTC efficiency. A cascade PTC consists of PTCs those are staged by transmission tubes in between, these can be a two-stage or even more stages, each stage is driven by the recovered work from the last stage by a well-designed long transmission tube. It is shown that the more stages it has, the closer the efficiency will approach the Carnot efficiency. A two-stage cascade pulse tube cooler consisted of a primary and a secondary stage working at 233 K is designed, fabricated and tested in our lab. Experimental results show that the efficiency is improved by 33% compared with the single stage PTC.

  9. Transverse Feedback System For The Cooler Synchrotron COSY-Jülich - First Results

    CERN Document Server

    Kamerdzhiev, V; Mohos, I

    2003-01-01

    The cooler synchrotron COSY delivers unpolarized and polarized protons and deuterons in the momentum range 300 MeV/c up to 3.65 GeV/c. Electron cooling at injection level and stochastic cooling covering the range from 1.5 GeV/c up to maximum momentum are available to prepare high precision beams for internal as well as for external experiments in hadron physics. In case of electron cooled beam the intensity is limited by transverse instabilities. The major losses are due to the vertical coherent beam oscillations. To damp these instabilities a transverse feedback system is under construction. First results with a simple feedback system are presented. Due to the feedback system operation the intensity and lifetime of the electron cooled proton beam at injection energy could be significantly increased. Measurements in frequency and time domain illustrate the performance of the system.

  10. Causes and prevention of corrosion in carbon steel natural gas coolers

    Energy Technology Data Exchange (ETDEWEB)

    Kotwica, D.J.; Minevski, L. [BetzDearborn, The Woodlands, TX (United States)

    1998-12-31

    Two case histories in which high pressure natural gas coolers had failed due to the presence of carbon dioxide are reviewed. CO{sub 2} along with CO and H{sub 2}S are acid gases usually present in natural gas feeds. Carbonic acid can form in aqueous condensate, lowering the pH and locally corroding mild steel tube metal. Stress corrosion cracking (SCC) can occur in tubing containing residual tensile stresses from welding or manufacturing. Bicarbonates and carbonates concentrated in condensate from CO{sub 2} and CO present in natural gas are required to produce SCC. Cathodic depolarizers such as oxygen in conjunction with the presence of carbonic acid will increase the corrosion rate of mild steel. Oxygen also increases the susceptibility of mild steel to carbonate SCC.

  11. Toward a cold electron beam in the Fermilab's Electron Cooler

    Energy Technology Data Exchange (ETDEWEB)

    Vitali S. Tupikov et al.

    2004-05-12

    Fermilab is developing a high-energy electron cooling system to cool 8.9-GeV/c antiprotons in the Recycler ring [1]. Cooling of antiprotons requires a round electron beam with a small angular spread propagating through 20-m long cooling section with a kinetic energy of 4.3 MeV. To confine the electron beam tightly and to keep its transverse angles below 0.1 mrad, the cooling section will be immersed into a solenoidal field of 50-150G. This paper describes the technique of measuring and adjusting the magnetic field quality in the cooling section and presents preliminary results of beam quality measurements in the cooler prototype.

  12. Upgrade of the radio frequency quadrupole cooler and buncher for the HIE-ISOLDE project

    CERN Document Server

    Babcock, Carla

    2013-01-01

    The upgrade to the ISOLDE facility, HIE-ISOLDE, will include an upgrade to the RFQCB (radio frequency quadrupole cooler and buncher), the focus of which will be fixing the problems of alignment with the current machine, improving the integrity of the vacuum system, stabilizing the internal gas pressure, and the changes associated with a new position. The beam passage inside the RFQCB has been simulated with an independent code to highlight the importance of the internal gas pressure, to motivate design changes in the new RFQCB and to explain ways to improve the performance of the current machine. The suspected misalignment of ISCOOL has been quantified, and, using a simulation of ions passing through the external injection electrodes, the effect of the misalignment on machine acceptance has been detailed. Plans for the future RFQCB test stand and HIE-ISOLDE installation have been outlined. (C) 2013 Elsevier B.V. All rights reserved.

  13. BEAM DYNAMICS ANALYSIS FOR THE ULTRA-FAST KICKER IN CIRCULAR COOLER RING OF JLEIC

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yulu [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Inst. Modern Phys., Chinese Academy of Sciences, Lanzhou, China; Wang, Haipeng [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Rimmer, Robert A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Wang, Shaoheng [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-05-01

    An ultra-fast kicker system consisting of four quarter wavelength resonator based deflecting cavities was developed that simultaneously resonates at 10 subharmonic modes of the 476.3MHz bunch repetition frequency. Thus every 10th bunch in the bunch train will experience a transverse kick while all the other bunches are undisturbed. This fast kicker is being developed for the Energy Recovery Linac (ERL) based electron Circular Cooler Ring (CCR) in the proposed Jefferson Lab Electron Ion Collider (JLEIC, previously MEIC). The electron bunches can be reused 10-30 turns thus the beam current in the ERL can be reduced to 1/10 - 1/30 (150mA - 50mA) of the cooling bunch current (1.5A). In this paper, several methods to synthesize such a kicker waveform and the comparison made by the beam dynamics tracking in Elegant will be discussed.

  14. Dry Air Cooler Modeling for Supercritical Carbon Dioxide Brayton Cycle Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Moisseytsev, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Sienicki, J. J. [Argonne National Lab. (ANL), Argonne, IL (United States); Lv, Q. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-07-28

    Modeling for commercially available and cost effective dry air coolers such as those manufactured by Harsco Industries has been implemented in the Argonne National Laboratory Plant Dynamics Code for system level dynamic analysis of supercritical carbon dioxide (sCO2) Brayton cycles. The modeling can now be utilized to optimize and simulate sCO2 Brayton cycles with dry air cooling whereby heat is rejected directly to the atmospheric heat sink without the need for cooling towers that require makeup water for evaporative losses. It has sometimes been stated that a benefit of the sCO2 Brayton cycle is that it enables dry air cooling implying that the Rankine steam cycle does not. A preliminary and simple examination of a Rankine superheated steam cycle and an air-cooled condenser indicates that dry air cooling can be utilized with both cycles provided that the cycle conditions are selected appropriately

  15. Urban street structure and traffic safety.

    Science.gov (United States)

    Mohan, Dinesh; Bangdiwala, Shrikant I; Villaveces, Andres

    2017-09-01

    This paper reports the influence of road type and junction density on road traffic fatality rates in U.S. cities. The Fatality Analysis Reporting System (FARS) files were used to obtain fatality rates for all cities for the years 2005-2010. A stratified random sample of 16 U.S. cities was taken, and cities with high and low road traffic fatality rates were compared on their road layout details (TIGER maps were used). Statistical analysis was done to determine the effect of junction density and road type on road traffic fatality rates. The analysis of road network and road traffic crash fatality rates in these randomly selected U.S. cities shows that, (a) higher number of junctions per road length was significantly associated with a lower motor- vehicle crash and pedestrian mortality rates, and, (b) increased number of kilometers of roads of any kind was associated with higher fatality rates, but an additional kilometer of main arterial road was associated with a significantly higher increase in total fatalities. When compared to non-arterial roads, the higher the ratio of highways and main arterial roads, there was an association with higher fatality rates. These results have important implications for road safety professionals. They suggest that once the road and street structure is put in place, that will influence whether a city has low or high traffic fatality rates. A city with higher proportion of wider roads and large city blocks will tend to have higher traffic fatality rates, and therefore in turn require much more efforts in police enforcement and other road safety measures. Urban planners need to know that smaller block size with relatively less wide roads will result in lower traffic fatality rates and this needs to be incorporated at the planning stage. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

  16. Making Maps from Planck LFI 30GHz Data with Asymmetric Beams and Cooler Noise

    Energy Technology Data Exchange (ETDEWEB)

    The Planck CTP Working Group; Ashdown, M.A.J.; Baccigalupi, C.; Bartlett, J.G.; Borrill, J.; Cantalupo, C.; de Gasperis, G.; Gorski, K.M.; Hivon, E.; Huffenberger, K.; Keihanen, E.; Keskitalo, R.; Kisner, T.; Hurki-Suonio, H.; Lawrence, C.R.; Natoli, P.; Poutanen, T.; Prezeau, G.; Reinecke, M.; Rocha, G.; Sandri, M.; Stompor, R..; Villa, F.; Wandelt, B.; de Troia, G.

    2008-06-19

    The Planck satellite will observe the full sky at nine frequencies from 30 to 857 GHz. Temperature and polarization frequency maps made from these observations are prime deliverables of the Planck mission. The goal of this paper is to examine the effects of four realistic instrument systematics in the 30 GHz frequency maps: non-axially-symmetric beams, sample integration, sorption cooler noise, and pointing errors. They simulated one year long observations of four 30 GHz detectors. The simulated timestreams contained CMB, foreground component (both galactic and extra-galactic), instrument nolise (correlated and white), and the four instrument systematic effects. They made maps from the timelines and examined the magnitudes of the systematics effects in the maps and their angular power spectra. They also compared the maps of different mapmaking codes to see how they performed. They used five mapmaking codes (two destripers and three optimal codes). None of their mapmaking codes makes an attempt to deconvolve the beam from its output map. Therefore all our maps had similar smoothing due to beams and sample integration. This is a complicated smoothing, because every map pixel has its own effective beam. Temperature to polarization cross-coupling due to beam mismatch causes a detectable bias in the TE spectrum of the CMB map. The effects of cooler noise and pointing errors did not appear to be major concerns for the 30 GHz channel. The only essential difference found so far between mapmaking codes that affects accuracy (in terms of residual RMS) is baseline length. All optimal codes give essentially indistiguishable results. A destriper gives the same result as the optimal codes when the baseline is set short enough (Madam). For longer baselines destripers (Springtide and Madam) require less computing resources but deliver a noisier map.

  17. Cooler temperatures destabilize RNA interference and increase susceptibility of disease vector mosquitoes to viral infection.

    Directory of Open Access Journals (Sweden)

    Zach N Adelman

    Full Text Available BACKGROUND: The impact of global climate change on the transmission dynamics of infectious diseases is the subject of extensive debate. The transmission of mosquito-borne viral diseases is particularly complex, with climatic variables directly affecting many parameters associated with the prevalence of disease vectors. While evidence shows that warmer temperatures often decrease the extrinsic incubation period of an arthropod-borne virus (arbovirus, exposure to cooler temperatures often predisposes disease vector mosquitoes to higher infection rates. RNA interference (RNAi pathways are essential to antiviral immunity in the mosquito; however, few experiments have explored the effects of temperature on the RNAi machinery. METHODOLOGY/PRINCIPAL FINDINGS: We utilized transgenic "sensor" strains of Aedes aegypti to examine the role of temperature on RNA silencing. These "sensor" strains express EGFP only when RNAi is inhibited; for example, after knockdown of the effector proteins Dicer-2 (DCR-2 or Argonaute-2 (AGO-2. We observed an increase in EGFP expression in transgenic sensor mosquitoes reared at 18°C as compared with 28°C. Changes in expression were dependent on the presence of an inverted repeat with homology to a portion of the EGFP sequence, as transgenic strains lacking this sequence, the double stranded RNA (dsRNA trigger for RNAi, showed no change in EGFP expression when reared at 18°C. Sequencing small RNAs in sensor mosquitoes reared at low temperature revealed normal processing of dsRNA substrates, suggesting the observed deficiency in RNAi occurs downstream of DCR-2. Rearing at cooler temperatures also predisposed mosquitoes to higher levels of infection with both chikungunya and yellow fever viruses. CONCLUSIONS/SIGNIFICANCE: This data suggest that microclimates, such as those present in mosquito breeding sites, as well as more general climactic variables may influence the dynamics of mosquito-borne viral diseases by affecting

  18. Nanoscale coatings for erosion and corrosion protection of copper microchannel coolers for high powered laser diodes

    Science.gov (United States)

    Flannery, Matthew; Fan, Angie; Desai, Tapan G.

    2014-03-01

    High powered laser diodes are used in a wide variety of applications ranging from telecommunications to industrial applications. Copper microchannel coolers (MCCs) utilizing high velocity, de-ionized water coolant are used to maintain diode temperatures in the recommended range to produce stable optical power output and control output wavelength. However, aggressive erosion and corrosion attack from the coolant limits the lifetime of the cooler to only 6 months of operation. Currently, gold plating is the industry standard for corrosion and erosion protection in MCCs. However, this technique cannot perform a pin-hole free coating and furthermore cannot uniformly cover the complex geometries of current MCCs involving small diameter primary and secondary channels. Advanced Cooling Technologies, Inc., presents a corrosion and erosion resistant coating (ANCERTM) applied by a vapor phase deposition process for enhanced protection of MCCs. To optimize the coating formation and thickness, coated copper samples were tested in 0.125% NaCl solution and high purity de-ionized (DIW) flow loop. The effects of DIW flow rates and qualities on erosion and corrosion of the ANCERTM coated samples were evaluated in long-term erosion and corrosion testing. The robustness of the coating was also evaluated in thermal cycles between 30°C - 75°C. After 1000 hours flow testing and 30 thermal cycles, the ANCERTM coated copper MCCs showed a corrosion rate 100 times lower than the gold plated ones and furthermore were barely affected by flow rates or temperatures thus demonstrating superior corrosion and erosion protection and long term reliability.

  19. Making maps from Planck LFI 30 GHz data with asymmetric beams and cooler noise

    Science.gov (United States)

    Ashdown, M. A. J.; Baccigalupi, C.; Bartlett, J. G.; Borrill, J.; Cantalupo, C.; de Gasperis, G.; de Troia, G.; Górski, K. M.; Hivon, E.; Huffenberger, K.; Keihänen, E.; Keskitalo, R.; Kisner, T.; Kurki-Suonio, H.; Lawrence, C. R.; Natoli, P.; Poutanen, T.; Prézeau, G.; Reinecke, M.; Rocha, G.; Sandri, M.; Stompor, R.; Villa, F.; Wandelt, B.; Planck Ctp Working Group

    2009-01-01

    The Planck satellite will observe the full sky at nine frequencies from 30 to 857 GHz. Temperature and polarization frequency maps made from these observations are prime deliverables of the Planck mission. The goal of this paper is to examine the effects of four realistic instrument systematics in the 30 GHz frequency maps: non-axially-symmetric beams, sample integration, sorption cooler noise, and pointing errors. We simulated one-year long observations of four 30 GHz detectors. The simulated timestreams contained cosmic microwave background (CMB) signal, foreground components (both galactic and extra-galactic), instrument noise (correlated and white), and the four instrument systematic effects. We made maps from the timelines and examined the magnitudes of the systematics effects in the maps and their angular power spectra. We also compared the maps of different mapmaking codes to see how they performed. We used five mapmaking codes (two destripers and three optimal codes). None of our mapmaking codes makes any attempt to deconvolve the beam from its output map. Therefore all our maps had similar smoothing due to beams and sample integration. This is a complicated smoothing, because each map pixel has its own effective beam. Temperature to polarization cross-coupling due to beam mismatch causes a detectable bias in the TE spectrum of the CMB map. The effects of cooler noise and pointing errors did not appear to be major concerns for the 30 GHz channel. The only essential difference found so far between mapmaking codes that affects accuracy (in terms of residual root-mean-square) is baseline length. All optimal codes give essentially indistinguishable results. A destriper gives the same result as the optimal codes when the baseline is set short enough (Madam). For longer baselines destripers (Springtide and Madam) require less computing resources but deliver a noisier map.

  20. Road and Street Centerlines, streets, Published in 2004, 1:4800 (1in=400ft) scale, Jasper County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — , published at 1:4800 (1in=400ft) scale, was produced all or in part from Orthoimagery information as of 2004. It is described as 'streets'. Data by this publisher...

  1. Road and Street Centerlines, Streets mm, Published in 2008, 1:24000 (1in=2000ft) scale, Washington County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — , published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2008. It is described as 'Streets mm'. Data by this publisher are...

  2. Road and Street Centerlines, Streets mm2, Published in 2008, 1:24000 (1in=2000ft) scale, Washington County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — , published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2008. It is described as 'Streets mm2'. Data by this publisher...

  3. Competition for the Elements of the City Environment for Irkutsk’s Public Spaces: Street Furniture, Street Design

    Directory of Open Access Journals (Sweden)

    Tatyana Danilova

    2016-10-01

    Full Text Available The article reviews the contest «Street furniture. Street design», which was held this summer by manufacturing company «PalpNord», International research laboratory of study and design of the urban environment «Urban Planning School» and the Union of Architects of Russia. The winners and their projects are also listed in the article.

  4. Reflective optics

    CERN Document Server

    Korsch, Dietrich

    1991-01-01

    This is the first book dedicated exclusively to all-reflective imaging systems. It is a teaching tool as well as a practical design tool for anyone who specializes in optics, particularly for those interested in telescopes, infrared, and grazing-incidence systems. The first part of the book describes a unified geometric optical theory of all-reflective imaging systems (from near-normal to grazing incidence) developed from basic principles. The second part discusses correction methods and a multitude of closed-form solutions of well-corrected systems, supplemented with many conventional and unc

  5. Importance-satisfaction analysis of street food sanitation and choice factor in Korea and Taiwan

    OpenAIRE

    Joo, Nami; Park, Sanghyun; Lee, Bohee; Yoon, Jiyoung

    2015-01-01

    BACKGROUND/OBJECTIVES The present study investigated Korean and Taiwan adults on the importance of and the satisfaction with street food sanitation and street food choice factor, in order to present management and improvement measures for street foods. SUBJECTS/METHODS The present study conducted a survey on 400 randomly chosen adults (200 Korean, 200 Taiwanese). General characteristics, eating habits, street food intake frequency, and preference by type of street food of respondents were che...

  6. Adaptation of the low-cost and low-power tactical split Stirling cryogenic cooler for aerospace applications

    Science.gov (United States)

    Veprik, A.; Zechtzer, S.; Pundak, N.; Kirkconnell, C.; Freeman, J.; Riabzev, S.

    2011-06-01

    Cryogenic coolers are often used in modern spacecraft in conjunction with sensitive electronics and sensors of military, commercial and scientific instrumentation. The typical space requirements are: power efficiency, low vibration export, proven reliability, ability to survive launch vibration/shock and long-term exposure to space radiation. A long-standing paradigm of exclusively using "space heritage" equipment has become the standard practice for delivering high reliability components. Unfortunately, this conservative "space heritage" practice can result in using outdated, oversized, overweight and overpriced cryogenic coolers and is becoming increasingly unacceptable for space agencies now operating within tough monetary and time constraints. The recent trend in developing mini and micro satellites for relatively inexpensive missions has prompted attempts to adapt leading-edge tactical cryogenic coolers for suitability in the space environment. The primary emphasis has been on reducing cost, weight and size. The authors are disclosing theoretical and practical aspects of a collaborative effort to develop a space qualified cryogenic refrigerator system based on the tactical cooler model Ricor K527 and the Iris Technology radiation hardened Low Cost Cryocooler Electronics (LCCE). The K27/LCCE solution is ideal for applications where cost, size, weight, power consumption, vibration export, reliability and time to spacecraft integration are of concern.

  7. 75 FR 55067 - Energy Conservation Program: Test Procedures for Walk-In Coolers and Walk-In Freezers

    Science.gov (United States)

    2010-09-09

    ... Concrete a. Floorless Coolers b. Pre-Installed Freezer Floor c. Insulated Floor Shipped by Manufacturer 7... structural members. (7) Alternatives to ASTM C1303. (8) Heat transfer through concrete. (9) U-factor of glass..., ``Standard Test Method for Predicting Long-Term Thermal Resistance of Closed-Cell Foam Insulation.''...

  8. Role of childhood aerobic fitness in successful street crossing.

    Science.gov (United States)

    Chaddock, Laura; Neider, Mark B; Lutz, Aubrey; Hillman, Charles H; Kramer, Arthur F

    2012-04-01

    Increased aerobic fitness is associated with improved cognition, brain health, and academic achievement during preadolescence. In this study, we extended these findings by examining the relationship between aerobic fitness and an everyday real-world task: street crossing. Because street crossing can be a dangerous multitask challenge and is a leading cause of injury in children, it is important to find ways to improve pedestrian safety. A street intersection was modeled in a virtual environment, and higher-fit (n = 13, 7 boys) and lower-fit (n = 13, 5 boys) 8- to 10-yr-old children, as determined by V˙O(2max) testing, navigated trafficked roads by walking on a treadmill that was integrated with an immersive virtual world. Child pedestrians crossed the street while undistracted, listening to music, or conversing on a hands-free cellular phone. Cell phones impaired street crossing success rates compared with the undistracted or music conditions for all participants (P = 0.004), a result that supports previous research. However, individual differences in aerobic fitness influenced these patterns (fitness × condition interaction, P = 0.003). Higher-fit children maintained street crossing success rates across all three conditions (paired t-tests, all P > 0.4), whereas lower-fit children showed decreased success rates when on the phone, relative to the undistracted (P = 0.018) and music (P = 0.019) conditions. The results suggest that higher levels of childhood aerobic fitness may attenuate the impairment typically associated with multitasking during street crossing. It is possible that superior cognitive abilities of higher-fit children play a role in the performance differences during complex real-world tasks.

  9. Reflective equilibrium

    NARCIS (Netherlands)

    van der Burg, W.; van Willigenburg, T.

    1998-01-01

    The basic idea of reflective equilibrium, as a method for theory construction and decision making in ethics, is that we should bring together a broad variety of moral and non-moral beliefs and, through a process of critical scrutiny and mutual adjustment, combine these into one coherent belief syste

  10. Reflective equilibrium

    NARCIS (Netherlands)

    van der Burg, W.; van Willigenburg, T.

    1998-01-01

    The basic idea of reflective equilibrium, as a method for theory construction and decision making in ethics, is that we should bring together a broad variety of moral and non-moral beliefs and, through a process of critical scrutiny and mutual adjustment, combine these into one coherent belief syste

  11. Street to Navy Enlisted Sailor Costing

    Science.gov (United States)

    2016-12-01

    and Commitment. 5. A training environment reflecting an emphasis on the health, safety and welfare of each recruit. RTCINST 3000.1A provides a more...of these costs would be training budgets and other miscellaneous costs associated with NAVCRUITCOM HQ. B. MILITARY ENTRANCE PROCESSING COMMAND...performed by analyzing USMEPCOM’s granular expense accounts instead of focusing on the fiscal year budget . C. RECRUIT TRAINING COMMAND The largest

  12. Re-Design dan Modifikasi Generator Cooler Heat Exchanger Pembangkit Listrik Tenaga Panas Bumi (PLTP untuk Meningkatkan Performasi

    Directory of Open Access Journals (Sweden)

    Ria Mahmudah

    2013-12-01

    Full Text Available Cooler Generator adalah alat yang berfungsi untuk menjaga temperature udara yang ada di dalam generator akibat kenaikan beban pada generator. Dan apabila kerja dari generator cooler tidak maksimal dalam menjaga temperatur di dalam generator maka akan terjadi overheating dan kerusakan pada generator, yang akan menyebabkan generator akan shutdown. Hal tersebut akan mengganggu proses produksi pada pembangkit listrik. Hal ini sering terjadi pada pembangkit listrik, salah satunya adalah PLTP dimana desain generator cooler sudah tidak dapat lagi menjaga temperatur didalam generator karena kenaikan beban. Sehingga perlu dilakukan desain ulang generator cooler untuk mendapatkan hasil yang maksimal yang dapat menjaga temperatur didalam generator agar generator tidak cepat mengalami overheating dan kerusakan. Penelitian ini dilakukan dengan menggunakan analisa perhitungan termodinamika dan perpindahan panas. Dilakukan trial error konfigurasi geometri heat exchanger berupa diameter tube dan P/Do yang didapat dari standart TEMA untuk mendapatkan UA yang maksimal dan mendapatkan nilai effectiveness tinggi. Dimana dalam re-desain ini menggunkan volume heat exchanger yang tetap dan jumlah dan jenis fin yang digunakan juga tetap. Dari analisa perhitungan, bahwa semakin besar nilai P/Do maka nilai effectiveness, NTU dan Pressure drop akan semakin kecil, begitu juga sebaliknya. Dari analisa didapatkan  konfigurasi geometri generator cooler yang menghasilkan performa yang maksimal yaitu  P/Do = 1,42 dengan  Do = 19,05 mm ; Di = 16,3 mm ; ST = 28,6 mm; SL= 24,7 mm ; Nt = 420. Dari perhitungan didapatkan bahwa geometri desain baru memiliki effektiveness 0,91 dan menghasilkan Th,o = 40,8 oC pada beban Th,I = 74,11 oC.

  13. The performance evaluation of WinOSPM model for urban street canyons of Nantes in France.

    Science.gov (United States)

    Gokhale, Sharad B; Rebours, Arnaud; Pavageau, Michel

    2005-01-01

    was done to evaluate the models performance using index of agreement and correlation coefficient. The index of agreement (d) and correlation coefficient (r) for all the streets show that estimated concentration levels are in good agreement with that of measurements. From the index of agreements, it can be inferred that model has very less potential for errors. The model's sensitivity to building-exceptions was also tested for the rue de Strasbourg. Results did not reflect this feature very well. It is perceived that the influence of this feature might have been suppressed in averaging the annual hourly values. This influence is apparently seen in hourly average time series variations. Finally, WinOSPM model was found a simple but very useful model. It could very well represent the detailed flow and dispersion conditions in urban streets.

  14. Pecan Street Grid Demonstration Program. Final technology performance report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2015-02-10

    This document represents the final Regional Demonstration Project Technical Performance Report (TPR) for Pecan Street Inc.’s (Pecan Street) Smart Grid Demonstration Program, DE-OE-0000219. Pecan Street is a 501(c)(3) smart grid/clean energy research and development organization headquartered at The University of Texas at Austin (UT). Pecan Street worked in collaboration with Austin Energy, UT, Environmental Defense Fund (EDF), the City of Austin, the Austin Chamber of Commerce and selected consultants, contractors, and vendors to take a more detailed look at the energy load of residential and small commercial properties while the power industry is undergoing modernization. The Pecan Street Smart Grid Demonstration Program signed-up over 1,000 participants who are sharing their home or businesses’s electricity consumption data with the project via green button protocols, smart meters, and/or a home energy monitoring system (HEMS). Pecan Street completed the installation of HEMS in 750 homes and 25 commercial properties. The program provided incentives to increase the installed base of roof-top solar photovoltaic (PV) systems, plug-in electric vehicles with Level 2 charging, and smart appliances. Over 200 participants within a one square mile area took advantage of Austin Energy and Pecan Street’s joint PV incentive program and installed roof-top PV as part of this project. Of these homes, 69 purchased or leased an electric vehicle through Pecan Street’s PV rebate program and received a Level 2 charger from Pecan Street. Pecan Street studied the impacts of these technologies along with a variety of consumer behavior interventions, including pricing models, real-time feedback on energy use, incentive programs, and messaging, as well as the corresponding impacts on Austin Energy’s distribution assets.The primary demonstration site was the Mueller community in Austin, Texas. The Mueller development, located less than three miles from the Texas State Capitol

  15. A qualitative enquiry into OpenStreetMap making

    Science.gov (United States)

    Lin, Yu-Wei

    2011-04-01

    Based on a case study on the OpenStreetMap community, this paper provides a contextual and embodied understanding of the user-led, user-participatory and user-generated produsage phenomenon. It employs Grounded Theory, Social Worlds Theory, and qualitative methods to illuminate and explores the produsage processes of OpenStreetMap making, and how knowledge artefacts such as maps can be collectively and collaboratively produced by a community of people, who are situated in different places around the world but engaged with the same repertoire of mapping practices. The empirical data illustrate that OpenStreetMap itself acts as a boundary object that enables actors from different social worlds to co-produce the Map through interacting with each other and negotiating the meanings of mapping, the mapping data and the Map itself. The discourses also show that unlike traditional maps that black-box cartographic knowledge and offer a single dominant perspective of cities or places, OpenStreetMap is an embodied epistemic object that embraces different world views. The paper also explores how contributors build their identities as an OpenStreetMaper alongside some other identities they have. Understanding the identity-building process helps to understand mapping as an embodied activity with emotional, cognitive and social repertoires.

  16. Energy and street foods (Bangladesh and Sri Lanka)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    Energy used by street food vendors is effectively replacing fuel consumption in the household, as studies have shown that street foods are often cheaper to buy than to prepare at home. Rapid urbanisation has led to a proliferation of these very small food outlets, particularly in the Asian subcontinent. Street foods provide employment and income to millions of people around the world, and provide low cost, affordable food to low income people. The project pilot tested improved biomass stoves with a selection of street food vendors. In Sri Lanka, laboratory tests were undertaken with the following three stoves: improved rice-husk burner, biomass gasifier, and double-mouth chimney stoves. From the pilot testing in Sri Lanka the key findings are that the efficient gasifier stove is not suitable for street food vendors, but there were some promising results from larger biomass stoves. In Bangladesh, the project piloted four types of biomass stove: single mouth, double mouth, bucket-type and institutional stove. As these were more established, the pilot focused on a method for reaching a larger number of beneficiaries, people were trained to make stoves in their own and in others' houses. Five workshops were held and over 540 stoves were built. Impact assessment exercises were undertaken in both countries. (author)

  17. The effects of city streets on an urban disease vector.

    Science.gov (United States)

    Barbu, Corentin M; Hong, Andrew; Manne, Jennifer M; Small, Dylan S; Quintanilla Calderón, Javier E; Sethuraman, Karthik; Quispe-Machaca, Víctor; Ancca-Juárez, Jenny; Cornejo del Carpio, Juan G; Málaga Chavez, Fernando S; Náquira, César; Levy, Michael Z

    2013-01-01

    With increasing urbanization vector-borne diseases are quickly developing in cities, and urban control strategies are needed. If streets are shown to be barriers to disease vectors, city blocks could be used as a convenient and relevant spatial unit of study and control. Unfortunately, existing spatial analysis tools do not allow for assessment of the impact of an urban grid on the presence of disease agents. Here, we first propose a method to test for the significance of the impact of streets on vector infestation based on a decomposition of Moran's spatial autocorrelation index; and second, develop a Gaussian Field Latent Class model to finely describe the effect of streets while controlling for cofactors and imperfect detection of vectors. We apply these methods to cross-sectional data of infestation by the Chagas disease vector Triatoma infestans in the city of Arequipa, Peru. Our Moran's decomposition test reveals that the distribution of T. infestans in this urban environment is significantly constrained by streets (p<0.05). With the Gaussian Field Latent Class model we confirm that streets provide a barrier against infestation and further show that greater than 90% of the spatial component of the probability of vector presence is explained by the correlation among houses within city blocks. The city block is thus likely to be an appropriate spatial unit to describe and control T. infestans in an urban context. Characteristics of the urban grid can influence the spatial dynamics of vector borne disease and should be considered when designing public health policies.

  18. Trees and Streets as Drivers of Urban Stormwater Nutrient Pollution.

    Science.gov (United States)

    Janke, Benjamin D; Finlay, Jacques C; Hobbie, Sarah E

    2017-09-05

    Expansion of tree cover is a major management goal in cities because of the substantial benefits provided to people, and potentially to water quality through reduction of stormwater volume by interception. However, few studies have addressed the full range of potential impacts of trees on urban runoff, which includes deposition of nutrient-rich leaf litter onto streets connected to storm drains. We analyzed the influence of trees on stormwater nitrogen and phosphorus export across 19 urban watersheds in Minneapolis-St. Paul, MN, U.S.A., and at the scale of individual streets within one residential watershed. Stormwater nutrient concentrations were highly variable across watersheds and strongly related to tree canopy over streets, especially for phosphorus. Stormwater nutrient loads were primarily related to road density, the dominant control over runoff volume. Street canopy exerted opposing effects on loading, where elevated nutrient concentrations from trees near roads outweighed the weak influence of trees on runoff reduction. These results demonstrate that vegetation near streets contributes substantially to stormwater nutrient pollution, and therefore to eutrophication of urban surface waters. Urban landscape design and management that account for trees as nutrient pollution sources could improve water quality outcomes, while allowing cities to enjoy the myriad benefits of urban forests.

  19. Between the streets and the shelter: everyday reorganization

    Directory of Open Access Journals (Sweden)

    Flávia Barbosa de Oliveira

    2015-07-01

    Full Text Available The street situation population has been shown as a growing urban phenomenon, becoming an object of interest to public managers and academics. This paper presents the results of a research aimed at understanding the context of street situation residents, under current provisory institutional shelter care, analyzing why the streets have become the home for some people; how the process of development and adaptation of daily activities in this new reality occurred; when and why they decided to leave the streets and how this process of production of a new daily life occurred since the institutional care; and how they organize and plan their departure from the host service. To this end, open interviews and production of narratives of life stories were conducted with seven residents of an institutional shelter care, along with participant observation for one year in the same service, where staff, residents and institutional dynamics were systematically observed. The results show that the users of this service have gone through different paths in life, with a trace in common: the growing weakening of bonds and purchasing power. The service seems to contribute to the movement of departure from the streets and provides immediate host, welcoming and functional autonomy. However, the departure movement from the shelter - that would provide other autonomies, development of social supports and integrated assistance - appears in the life stories as a difficult process with little institutional support. This work highlights the need to build debates and proposals on the homelessness process.

  20. Neighborhood sampling: how many streets must an auditor walk?

    Directory of Open Access Journals (Sweden)

    Medina Ashley V

    2010-03-01

    Full Text Available Abstract This study tested the representativeness of four street segment sampling protocols using the Pedestrian Environment Data Scan (PEDS in eleven neighborhoods surrounding public housing developments in Houston, TX. The following four street segment sampling protocols were used (1 all segments, both residential and arterial, contained within the 400 meter radius buffer from the center point of the housing development (the core were compared with all segments contained between the 400 meter radius buffer and the 800 meter radius buffer (the ring; all residential segments in the core were compared with (2 75% (3 50% and (4 25% samples of randomly selected residential street segments in the core. Analyses were conducted on five key variables: sidewalk presence; ratings of attractiveness and safety for walking; connectivity; and number of traffic lanes. Some differences were found when comparing all street segments, both residential and arterial, in the core to the ring. Findings suggested that sampling 25% of residential street segments within the 400 m radius of a residence sufficiently represents the pedestrian built environment. Conclusions support more cost effective environmental data collection for physical activity research.

  1. Exploring social inclusion strategies for public health research and practice: The use of participatory visual methods to counter stigmas surrounding street-based substance abuse in Colombia.

    Science.gov (United States)

    Ritterbusch, Amy E

    2016-01-01

    This paper presents the participatory visual research design and findings from a qualitative assessment of the social impact of bazuco and inhalant/glue consumption among street youth in Bogotá, Colombia. The paper presents the visual methodologies our participatory action research (PAR) team employed in order to identify and overcome the stigmas and discrimination that street youth experience in society and within state-sponsored drug rehabilitation programmes. I call for critical reflection regarding the broad application of the terms 'participation' and 'participatory' in visual research and urge scholars and public health practitioners to consider the transformative potential of PAR for both the research and practice of global public health in general and rehabilitation programmes for street-based substance abuse in Colombia in particular. The paper concludes with recommendations as to how participatory visual methods can be used to promote social inclusion practices and to work against stigma and discrimination in health-related research and within health institutions.

  2. Determination of polycyclic aromatic hydrocarbons in urban street dust: implications for human health.

    Science.gov (United States)

    Lorenzi, Damien; Entwistle, Jane A; Cave, Mark; Dean, John R

    2011-05-01

    The determination of sixteen polycyclic aromatic hydrocarbons in urban street dust has been done. Samples were collected from 12 sampling locations in a city centre location (Newcastle upon Tyne, north east England) and extracted using in situ pressurised fluid extraction followed by gas chromatography mass spectrometry. From the results it was possible to identify three groups, with respect to PAH concentration, with PAH contents ranging between 0.6-2.3 mg kg(-1), 15.6-22.5 mg kg(-1) and 36.1-46.0 mg kg(-1). The total PAH content of samples from these sampling sites has been compared to 22 urban locations around the world; comparable levels were found in these samples compared to the other cities around the world. The potential source of PAHs has been investigated by investigating the proportion of pyrogenic and petrogenic material in urban street dust using specific individual PAH ratios. The results indicate that the PAH content of urban street dust from the chosen sites are more likely to be due to pyrogenic sources i.e. vehicle exhaust emissions. The particle size fractions (PAHs in three selected sampling sites was investigated. In two of the selected sites the PAH content was independent of particle size whereas in sampling site 10 elevated PAH levels are noted in the PAHs was assessed in terms of a mean daily intake (based on an ingestion rate of 100 mg d(-1)). It was found that all 4-6 membered ring PAHs had concentrations in excess of the mean daily intake thereby reflecting a potential health risk, particularly in the smallest size particle fractions.

  3. My Life as a Quant: Reflections on Physics and Finance

    Science.gov (United States)

    Derman, Emanuel

    2004-09-01

    Emanuel Derman was one of the first physicists to move to Wall Street, and his career paralleled the growth of quantitative trading over the past twenty years. In My Life as a Quant, he traces his transformation from ambitious young scientist to managing director and head of the renowned Quantitative Strategies group at Goldman, Sachs & Co. Derman's tale recounts his adventures with quants, traders and other high fliers on Wall Street as he became the best-known quant in the business. He describes the struggles of research and his interactions with an assorted cast of famous scientists. He relates his impressions of some of the most creative minds on Wall Street, including Fischer Black, with whom he collaborated on the widely used Black-Derman-Toy model of interest rates. Throughout his story he reflects on the appropriate way to apply the refined methods of physics to the hurly-burly world of markets and the people that inhabit them.

  4. Pole-Like Street Furniture Decompostion in Mobile Laser Scanning Data

    Science.gov (United States)

    Li, F.; Oude Elberink, S.; Vosselman, G.

    2016-06-01

    Automatic semantic interpretation of street furniture has become a popular topic in recent years. Current studies detect street furniture as connected components of points above the street level. Street furniture classification based on properties of such components suffers from large intra class variability of shapes and cannot deal with mixed classes like traffic signs attached to light poles. In this paper, we focus on the decomposition of point clouds of pole-like street furniture. A novel street furniture decomposition method is proposed, which consists of three steps: (i) acquirement of prior-knowledge, (ii) pole extraction, (iii) components separation. For the pole extraction, a novel global pole extraction approach is proposed to handle 3 different cases of street furniture. In the evaluation of results, which involves the decomposition of 27 different instances of street furniture, we demonstrate that our method decomposes mixed classes street furniture into poles and different components with respect to different functionalities.

  5. OSMnx: New Methods for Acquiring, Constructing, Analyzing, and Visualizing Complex Street Networks

    CERN Document Server

    Boeing, Geoff

    2016-01-01

    Scholars have studied street networks in many ways. However, there are some limitations to the current urban planning/street network analysis literature. To address these challenges, this study presents a new tool to make the collection of data and creation and analysis of street networks simple, consistent, and automatable. OSMnx is a new Python package that downloads administrative boundary shapes and street networks from OpenStreetMap. OSMnx contributes five significant new capabilities for researchers and city planners: first, the automatic downloading of administrative place boundaries and shapefiles; second, the tailored and automated downloading and constructing of street networks from OpenStreetMap (including driving, walking, biking, etc.); third, the automated correction and simplification of network topology; fourth, the ability to save street networks to disk as shapefiles, GraphML, or SVG files; and fifth, the ability to analyze street networks, calculate routes, project and visualize the network...

  6. A review of variables of urban street connectivity for spatial connection

    Science.gov (United States)

    Mohamad, W. S. N. W.; Said, I.

    2014-02-01

    Several studies on street connectivity in cities and towns have been modeled on topology, morphology, technology and psychology of people living in the urban environment. Street connectivity means the connection of streets that offers people alternative routes. However, there emerge difficulties to determine the suitable variables and analysis to be chosen in defining the accurate result for studies street connectivity. The aim of this paper is to identify variables of street connectivity by applying GIS and Space Syntax. This paper reviews the variables of street connectivity from 15 past articles done in 1990s to early 2000s from journals of nine disciplines on Environment and Behavior, Planning and Design, Computers, Environment and Urban Systems, Applied Earth Observation and Geo-information, Environment and Planning, Physica A: Statistical Mechanics and its Applications, Environmental Psychology, Social Science and Medicine and Building and Environment. From the review, there are four variables found for street connectivity: link (streets-streets, street-nodes or node-streets, nodes-nodes), accessibility, least-angle, and centrality. Space syntax and GIS are suitable tools to analyze the four variables relating to systematic street systems for pedestrians. This review implies that planners of the street systems, in the aspect of street connectivity in cities and towns, should consider these four variables.

  7. Ergonomics and design: traffic sign and street name sign.

    Science.gov (United States)

    Moroni, Janaina Luisa da Silva; Aymone, José Luís Farinatti

    2012-01-01

    This work proposes a design methodology using ergonomics and anthropometry concepts applied to traffic sign and street name sign projects. Initially, a literature revision on cognitive ergonomics and anthropometry is performed. Several authors and their design methodologies are analyzed and the aspects to be considered in projects of traffic and street name signs are selected and other specific aspects are proposed for the design methodology. A case study of the signs of "Street of Antiques" in Porto Alegre city is presented. To do that, interviews with the population are made to evaluate the current situation of signs. After that, a new sign proposal with virtual prototyping is done using the developed methodology. The results obtained with new interviews about the proposal show the user satisfaction and the importance of cognitive ergonomics to development of this type of urban furniture.

  8. Automatic Adjustment of Wide-Base Google Street View Panoramas

    Science.gov (United States)

    Boussias-Alexakis, E.; Tsironisa, V.; Petsa, E.; Karras, G.

    2016-06-01

    This paper focuses on the issue of sparse matching in cases of extremely wide-base panoramic images such as those acquired by Google Street View in narrow urban streets. In order to effectively use affine point operators for bundle adjustment, panoramas must be suitably rectified to simulate affinity. To this end, a custom piecewise planar projection (triangular prism projection) is applied. On the assumption that the image baselines run parallel to the street façades, the estimated locations of the vanishing lines of the façade plane allow effectively removing projectivity and applying the ASIFT point operator on panorama pairs. Results from comparisons with multi-panorama adjustment, based on manually measured image points, and ground truth indicate that such an approach, if further elaborated, may well provide a realistic answer to the matching problem in the case of demanding panorama configurations.

  9. [A case of agnosia for streets without visual memory disturbance].

    Science.gov (United States)

    Aoki, Kazuko; Hiroki, Masahiko; Bando, Mitsuaki; Miyamoto, Kazuhito; Hirai, Shunsaku

    2003-06-01

    A 70-year-old, right-handed man was admitted to our hospital for his sudden-onset topographical disorientation. He failed to find his way to familiar places, but he knew distance and direction to the places. Neurological examination revealed homonymous left-upper quadrantanopsia on Goldmann perimeter and hypoesthesia over the left side of his body. Magnetic resonance imaging showed an abnormal intensity area at the right medial temporo-occipital region, due to the infarct of the right posterior cerebral arterial territory. The neuropsychological examination revealed agnosia for streets, and prosopagnosia without any other disturbance of visual perception. Both visual and topographical memories were intact. It is suggested that, in this case, the agnosia for streets was caused by impairment of recognizing familiar streets and houses or disconnection between their recognition and memory.

  10. OpenStreetMap e la prima conferenza OSMit

    Directory of Open Access Journals (Sweden)

    Luca Dellucchi

    2009-03-01

    Full Text Available OpenStreetMap and the first OSMit conferenceThis month’s article features a brief presentation of the OpenStreetMap project, initiated by a single user in 2004 with the aim of creating a free map of the world, editable following wiki-like rules, and evolved in a few years in a system involving over 100,000 users contributing data from all over the world. The interest in presenting this topic is related also to the recent occurrence of the first meeting of the Italian OpenStreetMap Community. The meeting took place in Trento in early June 2009, organized by the Fondazione Bruno Kessler, and demonstrated the liveliness of this community, showcasing experience conducted over the past year, and highlighting developments for the future.

  11. 华尔街重塑迷思%Reflection on Wall Street

    Institute of Scientific and Technical Information of China (English)

    乔晓会

    2010-01-01

    @@ 纽约曼哈顿第七大道745号,靠近著名的百老汇大街路口. 两年前,挂在这栋大楼的招牌,是深绿色的"Lehman Brothers".曾经的雷曼兄弟投资银行总部,现在则挂上了水蓝色的"Barclays"(巴克莱银行,Barclays Bank).创立于1690年的老牌英国银行巴克菜,在2008年9月16日宣布收购雷曼兄弟投资银行,华尔街第四大投资银行、拥有158年历史的雷曼兄弟,从此走入历史.

  12. Streets of Paris, sunflower seeds, and Nobel prizes. Reflections on the quantitative paradigm of public health

    NARCIS (Netherlands)

    J.P. Mackenbach (Johan)

    2004-01-01

    textabstractQuantitative methods are central to public health and public health research. The historical roots and philosophical foundations of this predilection for the quantitative, however, are little known and seldom discussed.

  13. [Street food among children: a study in north Tunisia].

    Science.gov (United States)

    Neffati, Larbi; Ridha, Hamza; Kolsteren, Patrick; Hilderbrand, Katherine

    2004-01-01

    As urbanization increases in Tunisia, eating meals outside the home is becoming more frequent. Children are prime consumers for the fast food sold in the streets. Neither their nor their parents' attitude towards street food is well documented as yet. This study was conducted in the city of Bizerte in February 1998. Its aim was to gather information about street food and parents' and children's attitudes towards it to help organize educational sessions with the children, parents, teachers, and vendors. The study interviewed 421 primary school children, ranging in age from 6 to 15 years (mean age: 10 years), from 24 schools. Half received pocket money, a percentage that did not differ by sex. Three quarters of the children used more than 75% of their pocket money to buy street food. The items bought most frequently were candy (27.2%), sandwiches (23.9%), pastries (23.9%), sunflower seeds and peanuts (21%), and either pizza, chocolate, or cheese (20.3%); the largest proportion of money was spent on sandwiches. In more than half the cases (55.7% of the children), the main motivation for buying street food was either to replace or fill out a meal at home, with sandwiches or pastries. The parents' monthly income did not influence the children's purchasing behavior, but the rhythm of receiving pocket money did. Most children were satisfied with the nutritional and hygienic quality of the food available, but their opinion of this quality as well as the reasons for buying the food and the prices spent on it differed considerably from that of their parents. This study highlights the important role of street foods in the daily diet of schoolchildren and the need for appropriate nutrition education in primary schools.

  14. Exploring the World using Street View 360 Images

    Science.gov (United States)

    Bailey, J.

    2016-12-01

    The phrase "A Picture is Worth a Thousand Words" is an idiom of unknown 20th century origin. There is some belief that the modern use of the phrase stems from an article in a 1921 issue of a popular trade journal, that used "One Look is Worth A Thousand Words" to promote the use of images in advertisements on the sides of streetcars. There is a certain irony to this as nearly a century later the camera technologies on "Street View cars" are collecting images that look everywhere at once. However, while it can be to fun drive along the World's streets, it was the development of Street View imaging systems that could be mounted on other modes of transport or capture platforms (Street View Special Collects) that opened the door for these 360 images to become a tool for exploration and storytelling. Using Special Collect imagery captured in "off-road" and extreme locations, scientists are now using Street View images to assess changes to species habitats, show the impact of natural disasters and even perform "armchair" geology. A powerful example is the imagery captured before and after the 2011 earthquake and tsunami that devastated Japan. However, it is use of the immersive nature of 360 images that truly allows them to create wonder and awe, especially when combined with Virtual Reality (VR) viewers. Combined with the Street View App or Google Expeditions, VR provides insight into what it is like to swim with sealions in the Galapagos or climb El Capitan in Yosemite National Park. While these image could never replace experiencing these locations in real-life, they can inspire the viewer to explore and learn more about the many wonders of our planet. https://www.google.com/streetview/https://www.google.com/expeditions/

  15. Lonely drinking fountains and comforting coolers: paradoxes of water value and ironies of water use.

    Science.gov (United States)

    Kaplan, Martha

    2011-01-01

    This article focuses ethnographically on Americans and technologies of drinking water, as tokens of and vehicles for health, agency, and surprising kinds of community. Journalists and water scholars have argued that bottled water is a material concomitant of privatization and alienation in U.S. society. But, engaging Latour, this research shows that water technologies and the groups they assemble, are plural. Attention to everyday entwining of workplace lives with drinking fountains, single-serve bottles, and spring water coolers shows us several different quests, some individualized, some alienated, but some seeking health via public, collective care, acknowledgment of stakeholding, and community organizing. Focused on water practices on a college campus, in the roaring 1990s and increasingly sober 2000s in the context of earlier U.S. water histories of inclusion and exclusion, I draw on ethnographic research from the two years that led up to the recession and the presidential election of 2008. I argue for understanding of water value through attention to water use, focusing both on the social construction of water and the use of water for social construction.

  16. Drought and Cooler Temperatures Are Associated with Higher Nest Survival in Mountain Plovers

    Directory of Open Access Journals (Sweden)

    Victoria J Dreitz

    2012-06-01

    Full Text Available Native grasslands have been altered to a greater extent than any other biome in North America. The habitats and resources needed to support breeding performance of grassland birds endemic to prairie ecosystems are currently threatened by land management practices and impending climate change. Climate models for the Great Plains prairie region predict a future of hotter and drier summers with strong multiyear droughts and more frequent and severe precipitation events. We examined how fluctuations in weather conditions in eastern Colorado influenced nest survival of an avian species that has experienced recent population declines, the Mountain Plover (Charadrius montanus. Nest survival averaged 27.2% over a 7-yr period (n = 936 nests and declined as the breeding season progressed. Nest survival was favored by dry conditions and cooler temperatures. Projected changes in regional precipitation patterns will likely influence nest survival, with positive influences of predicted declines in summer rainfall yet negative effects of more intense rain events. The interplay of climate change and land use practices within prairie ecosystems may result in Mountain Plovers shifting their distribution, changing local abundance, and adjusting fecundity to adapt to their changing environment.

  17. Optimization Of Thermo-Electric Coolers Using Hybrid Genetic Algorithm And Simulated Annealing

    Directory of Open Access Journals (Sweden)

    Khanh Doan V.K.

    2014-06-01

    Full Text Available Thermo-electric Coolers (TECs nowadays are applied in a wide range of thermal energy systems. This is due to their superior features where no refrigerant and dynamic parts are needed. TECs generate no electrical or acoustical noise and are environmentally friendly. Over the past decades, many researches were employed to improve the efficiency of TECs by enhancing the material parameters and design parameters. The material parameters are restricted by currently available materials and module fabricating technologies. Therefore, the main objective of TECs design is to determine a set of design parameters such as leg area, leg length and the number of legs. Two elements that play an important role when considering the suitability of TECs in applications are rated of refrigeration (ROR and coefficient of performance (COP. In this paper, the review of some previous researches will be conducted to see the diversity of optimization in the design of TECs in enhancing the performance and efficiency. After that, single-objective optimization problems (SOP will be tested first by using Genetic Algorithm (GA and Simulated Annealing (SA to optimize geometry properties so that TECs will operate at near optimal conditions. Equality constraint and inequality constraint were taken into consideration.

  18. Parametric analysis of a novel cryogenic CO2 capture system based on Stirling coolers.

    Science.gov (United States)

    Song, Chun Feng; Kitamura, Yutaka; Li, Shu Hong; Jiang, Wei Zhong

    2012-11-20

    CO(2) capture and storage (CCS) is an important alternative to control greenhouse gas (GHG) effects. In previous work, a novel desublimation CO(2) capture process has been exploited making use of three free piston Stirling coolers (namely, SC-1, SC-2, and SC-3, respectively). Based on the developed system, moisture and CO(2) in the flue gas can condense and desublimate in the prefreezing and main-freezing towers, respectively. Meanwhile, the storage column is chilled by SC-3 to preserve the frosted CO(2), and permanent gas (such as N(2)) passes through the system without phase change. The whole process can be implemented at atmospheric pressure and reduce the energy penalty (e.g., solvent regeneration and pressure drop) in other technologies. In this work, the influence of process parameters has been investigated in detail. The optimal conditions for the system are as follows: idle operating time is 240 min, flow rate is 5 L/min, vacuum degree of the interlayer is 2.2 × 10(3) Pa, and temperatures of SC-1, -2, and -3 are -30, -120, and -120 °C, respectively. Under these conditions, the energy consumption of the system is around 0.5 MJ(electrical)/kg CO(2) with above 90% CO(2) recovery.

  19. Dewar cooler integrated MWIR spectrometer for high rates and high dynamic range measurements

    Science.gov (United States)

    Guérineau, N.; Rommeluère, S.; Ferrec, Y.; Druart, G.; Lasfargues, G.; de Borniol, E.; Magli, S.

    2015-06-01

    There is a need for compact, hand-held, spectrometers for the measurement of spectral signatures of chemicals or objects. To achieve this goal, a new concept of Fourier-transform interferometer (FTIR) directly integrated on the infrared focal plane array (FPA) has been developed at ONERA. The fundamental properties of this key element called MICROSPOC will be recalled and we will see how those properties can be exploited to get a snapshot, compact and cryogenic MWIR spectrometer. These design rules have been applied to develop a very compact device that combines the metrological properties of a FTIR-FPA of quantum HgCdTe technology with the radiometric performances of a last generation Sofradir detection block (Infrared Detector Dewar Cooler Assembly - IDDCA). The experimental performances of the prototype will be presented, in terms of spectral resolution, acquisition rate, dynamic range and noise equivalent spectral radiance. We will discuss at the end the potential of this technology to meet the requirements of different applications.

  20. Feasibility of a solar-assisted winter air-conditioning system using evaporative air-coolers

    Directory of Open Access Journals (Sweden)

    Mohamed M. El-Awad

    2011-03-01

    Full Text Available The paper presents a winter air-conditioning system which is suitable for regions with mildly cold but dry winters. The system modifies the evaporative air-cooler that is commonly used for summer air-conditioning in such regions by adding a heating process after the humidification process. The paper describes a theoretical model that is used to estimate the system's water and energy consumption. It is shown that a 150-LPD solar heater is adequate for air-conditioning a 500 ft3/min (14.4 m3/min air flow rate for four hours of operation. The maximum air-flow rate that can be heated by a single solar water-heater for four hours of operation is about 900-cfm, unless a solar water heater large than a 250-LPD heater is used. For the 500 ft3/min air flow rate the paper shows that the 150, 200, 250 and 300 LPD solar water-heaters can provide air-conditioning for 4, 6, 8 and 10 hours, respectively, while consuming less energy than the equivalent refrigerated-type air-conditioner.