Comparison of indoor air distribution and thermal environment for different combinations of radiant heating systems with mechanical ventilation systems

DEFF Research Database (Denmark)

Wu, Xiaozhou; Fang, Lei; Olesen, Bjarne W.

2018-01-01

A hybrid system with a radiant heating system and a mechanical ventilation system, which is regarded as an advanced heating, ventilation and air-conditioning (HVAC) system, has been applied in many modern buildings worldwide. To date, almost no studies focused on comparative analysis of the indoor...... air distribution and the thermal environment for all combinations of radiant heating systems with mechanical ventilation systems. Therefore, in this article, the indoor air distribution and the thermal environment were comparatively analyzed in a room with floor heating (FH) or ceiling heating (CH......) and mixing ventilation (MV) or displacement ventilation (DV) when the supply air temperature ranged from 15.0°C to 19.0°C. The results showed that the temperature effectiveness values were 1.05–1.16 and 0.95–1.02 for MV+ FH and MV+ CH, respectively, and they were 0.78–0.91 and 0.51–0.67 for DV + FH and DV...

Sensitivity analysis of the thermal performance of radiant and convective terminals for cooling buildings

DEFF Research Database (Denmark)

Le Dréau, J.; Heiselberg, P.

2014-01-01

Heating and cooling terminals can be classified in two main categories: convective terminals (e.g. active chilled beam, air conditioning) and radiant terminals. The mode of heat transfer of the two emitters is different: the first one is mainly based on convection, whereas the second one is based...... conducted to determine the parameters influencing their thermal performance the most. The air change rate, the outdoor temperature and the air temperature stratification have the largest effect on the cooling need (maintaining a constant operative temperature). For air change rates higher than 0.5 ACH...

Optimum pulse duration and radiant exposure for vascular laser therapy of dark port-wine skin: a theoretical study

International Nuclear Information System (INIS)

Tunnell, James W.; Anvari, Bahman; Wang, Lihong V.

2003-01-01

Laser therapy for cutaneous hypervascular malformations such as port-wine stain birthmarks is currently not feasible for dark-skinned individuals. We study the effects of pulse duration, radiant exposure, and cryogen spray cooling (CSC) on the thermal response of skin, using a Monte Carlo based optical-thermal model. Thermal injury to the epidermis decreases with increasing pulse duration during irradiation at a constant radiant exposure; however, maintaining vascular injury requires that the radiant exposure also increase. At short pulse durations, only a minimal increase in radiant exposure is necessary for a therapeutic effect to be achieved because thermal diffusion from the vessels is minimal. However, at longer pulse durations the radiant exposure must be greatly increased. There exists an optimum pulse duration at which minimal damage to the epidermis and significant injury within the targeted vasculature occur. For example, the model predicts optimum pulse durations of approximately 1.5, 6, and 20 ms for vessel diameters of 40, 80, and 120 μm, respectively. Optimization of laser pulse duration and radiant exposure in combination with CSC may offer a means to treat cutaneous lesions in dark-skinned individuals

Radiant cooling of an enclosure

International Nuclear Information System (INIS)

Chebihi, Abdeslam; Byun, Ki-Hong; Wen Jin; Smith, Theodore F.

2006-01-01

The purpose of this study is to analyze the potential for radiant cooling using the atmospheric sky window and to evaluate the desired characteristics of a radiant cooling material (RCM) applied to the ceiling window of a three-dimensional enclosure. The thermal characteristics of the system are governed by the geometry, ambient temperature, sky radiative temperature, amount of solar energy and its direction, heat transfer modes, wall radiative properties, and radiative properties of the RCMs. A semi-gray band analysis is utilized for the solar and infrared bands. The radiosity/irradiation method is used in each band to evaluate the radiant exchanges in the enclosure. The radiative properties for the RCM are varied in a parametric study to identify the desired properties of RCMs. For performance simulation of real RCMs, the radiative properties are calculated from spectral data. The desired solar property is a high reflectance for both opaque and semi-transparent RCMs. For a semi-transparent RCM, a low value of the solar transmittance is preferred. The desired infrared property is a high emittance for an opaque RCM. For a semi-transparent RCM, a high infrared transmittance is desired, and the emittance should be greater than zero

Radiant floor cooling coupled with dehumidification systems in residential buildings: A simulation-based analysis

International Nuclear Information System (INIS)

Zarrella, Angelo; De Carli, Michele; Peretti, Clara

2014-01-01

Highlights: • The floor radiant cooling in a typical apartment is analyzed. • Dehumidification devices, fan-coil and mechanical ventilation are compared. • The results are analyzed in terms of both thermal comfort and energy consumption. • The energy consumption of the dehumidifiers is higher than that of other systems. • The mechanical ventilation decreases the moisture level better than other systems. - Abstract: The development of radiant cooling has stimulated an interest in new systems based on coupling ventilation with radiant cooling. However, radiant cooling systems may cause condensation to form on an active surface under warm and humid conditions during the cooling season. This phenomenon occurs when surface temperature falls below dew point. To prevent condensation, air humidity needs to be reduced with a dehumidification device or a mechanical ventilation system. There are two main options to achieve this. The first is to use dehumidification devices that reduce humidity, but are not coupled with ventilation, i.e. devices that handle room air and leave air change to infiltrations. The second is to combine a mechanical ventilation system with dehumidifying finned coils. This study analyzes the floor radiant cooling of a typical residential apartment within a multi-storey building in three Italian climate zones by means of a detailed simulation tool. Five systems were compared in terms of both indoor thermal comfort and energy consumption: radiant cooling without dehumidification; radiant cooling with a soft dehumidification device; radiant cooling with a dehumidification device which also supplies sensible cooling; radiant cooling coupled with fan coils; and radiant cooling with a mechanical ventilation system which dehumidifies and cools

Radiant Floor Cooling Systems

DEFF Research Database (Denmark)

Olesen, Bjarne W.

2008-01-01

In many countries, hydronic radiant floor systems are widely used for heating all types of buildings such as residential, churches, gymnasiums, hospitals, hangars, storage buildings, industrial buildings, and smaller offices. However, few systems are used for cooling.This article describes a floor...... cooling system that includes such considerations as thermal comfort of the occupants, which design parameters will influence the cooling capacity and how the system should be controlled. Examples of applications are presented....

Experimental evaluation of an active solar thermoelectric radiant wall system

International Nuclear Information System (INIS)

Liu, ZhongBing; Zhang, Ling; Gong, GuangCai; Han, TianHe

2015-01-01

Highlights: • A novel active solar thermoelectric radiant wall are proposed and tested. • The novel wall can control thermal flux of building envelope by using solar energy. • The novel wall can eliminate building envelop thermal loads and provide cooling capacity for space cooling. • Typical application issues including connection strategies, coupling with PV system etc. are discussed. - Abstract: Active solar thermoelectric radiant wall (ASTRW) system is a new solar wall technology which integrates thermoelectric radiant cooling and photovoltaic (PV) technologies. In ASTRW system, a PV system transfers solar energy directly into electrical energy to power thermoelectric cooling modes. Both the thermoelectric cooling modes and PV system are integrated into one enclosure surface as radiant panel for space cooling and heating. Hence, ASTRW system presents fundamental shift from minimizing building envelope energy losses by optimizing the insulation thickness to a new regime where active solar envelop is designed to eliminate thermal loads and increase the building’s solar gains while providing occupant comfort in all seasons. This article presents an experimental study of an ASTRW system with a dimension of 1580 × 810 mm. Experimental results showed that the inner surface temperature of the ASTRW is 3–8 °C lower than the indoor temperature of the test room, which indicated that the ASTRW system has the ability to control thermal flux of building envelope by using solar energy and reduce the air conditioning system requirements. Based on the optimal operating current of TE modules and the analysis based upon PV modeling theories, the number and type of the electrical connections for the TE modules in ASTRW system are discussed in order to get an excellent performance in the operation of the ASTRW system

Integrated thermal infrared imaging and Structure-from-Motion photogrametry to map apparent temperature and radiant hydrothermal heat flux at Mammoth Mountain, CA USA

Science.gov (United States)

Lewis, Aaron; George Hilley,; Lewicki, Jennifer L.

2015-01-01

This work presents a method to create high-resolution (cm-scale) orthorectified and georeferenced maps of apparent surface temperature and radiant hydrothermal heat flux and estimate the radiant hydrothermal heat emission rate from a study area. A ground-based thermal infrared (TIR) camera was used to collect (1) a set of overlapping and offset visible imagery around the study area during the daytime and (2) time series of co-located visible and TIR imagery at one or more sites within the study area from pre-dawn to daytime. Daytime visible imagery was processed using the Structure-from-Motion photogrammetric method to create a digital elevation model onto which pre-dawn TIR imagery was orthorectified and georeferenced. Three-dimensional maps of apparent surface temperature and radiant hydrothermal heat flux were then visualized and analyzed from various computer platforms (e.g., Google Earth, ArcGIS). We demonstrate this method at the Mammoth Mountain fumarole area on Mammoth Mountain, CA. Time-averaged apparent surface temperatures and radiant hydrothermal heat fluxes were observed up to 73.7 oC and 450 W m-2, respectively, while the estimated radiant hydrothermal heat emission rate from the area was 1.54 kW. Results should provide a basis for monitoring potential volcanic unrest and mitigating hydrothermal heat-related hazards on the volcano.

Airflow and Heat Transfer in the Slot-Vented Room with Radiant Floor Heating Unit

Directory of Open Access Journals (Sweden)

Xiang-Long Liu

2012-01-01

Full Text Available Radiant floor heating has received increasing attention due to its diverse advantages, especially the energy saving as compared to the conventional dwelling heating system. This paper presents a numerical investigation of airflow and heat transfer in the slot-vented room with the radiant floor heating unit. Combination of fluid convection and thermal radiation has been implemented through the thermal boundary conditions. Spatial distributions of indoor air temperature and velocity, as well as the heat transfer rates along the radiant floor and the outer wall, have been presented and analyzed covering the domains from complete natural convection to forced convection dominated flows. The numerical results demonstrate that the levels of average temperature in the room with lateral slot-ventilation are higher than those without slot-ventilation, but lower than those in the room with ceiling slot-ventilation. Overall, the slot-ventilation room with radiant floor heating unit could offer better indoor air quality through increasing the indoor air temperature and fresh air exchanging rate simultaneously. Concerning the airborne pollutant transports and moisture condensations, the performance of radiant floor heating unit will be further optimized in our future researches.

Performance evaluation of radiant cooling system application on a university building in Indonesia

Science.gov (United States)

Satrio, Pujo; Sholahudin, S.; Nasruddin

2017-03-01

The paper describes a study developed to estimate the energy savings potential of a radiant cooling system installed in an institutional building in Indonesia. The simulations were carried out using IESVE to evaluate thermal performance and energy consumption The building model was calibrated using the measured data for the installed radiant system. Then this calibrated model was used to simulate the energy consumption and temperature distribution to determine the proportional energy savings and occupant comfort under different systems. The result was radiant cooling which integrated with a Dedicated Outside Air System (DOAS) could make 41,84% energy savings compared to the installed cooling system. The Computational Fluid Dynamics (CFD) simulation showed that a radiant system integrated with DOAS provides superior human comfort than a radiant system integrated with Variable Air Volume (VAV). Percentage People Dissatisfied was kept below 10% using the proposed system.

The influence of local effects on thermal sensation under non-uniform environmental conditions — Gender differences in thermophysiology, thermal comfort and productivity during convective and radiant cooling

DEFF Research Database (Denmark)

Schellen, L.; Loomans, M.G.L.C.; de Wit, M.H.

2012-01-01

, thermal comfort and productivity in response to thermal non-uniform environmental conditions. Twenty healthy subjects (10 males and 10 females, age 20–29years) were exposed to two different experimental conditions: a convective cooling situation (CC) and a radiant cooling situation (RC). During...... the experiments physiological responses, thermal comfort and productivity were measured. The results show that under both experimental conditions the actual mean thermal sensation votes significantly differ from the PMV-index; the subjects are feeling colder than predicted. Furthermore, the females are more...... of the occupants. Non-uniform thermal conditions, which may occur due to application of high temperature cooling systems, can be responsible for discomfort. Contradictions in literature exist regarding the validity of the often used predicted mean vote (PMV) index for both genders, and the index is not intended...

Design and construction of a regenerative radiant tube burner

International Nuclear Information System (INIS)

Henao, Diego Alberto; Cano C, Carlos Andres; Amell Arrieta, Andres A.

2002-01-01

The technological development of the gas industry in Colombia, aiming at efficient and safe use of the natural gas, requires the assimilation and adaptation of new generation, technologies for this purpose in this article results are presented on the design, construction and characterization of a prototype of a burner of regenerative radiant robe with a thermal power of 9,94 kW and a factor of air 1,05. This system takes advantage of the high exit temperature of the combustion smokes, after they go trough a metallic robe where they transfer the heat by radiation, to heat a ceramic channel that has the capacity to absorbing a part of the heat of the smokes and then transferring them to a current of cold air. The benefits of air heating are a saving in fuel, compared with other processes that don't incorporate the recovery of heat from the combustion gases. In this work it was possible to probe a methodology for the design of this type of burners and to reach maximum temperatures of heating of combustion air of 377,9 centigrade degrees, using a material available in the national market, whose regenerative properties should be studied in depth

PERFORMANCE EVALUATION OF CEILING RADIANT COOLING SYSTEM IN COMPOSITE CLIMATE

Energy Technology Data Exchange (ETDEWEB)

Sharma, Anuj [Malaviya National Institute of Technology (MNIT), Jaipur, India; Mathur, Jyotirmay [Malaviya National Institute of Technology (MNIT), Jaipur, India; Bhandari, Mahabir S [ORNL

2015-01-01

Radiant cooling systems are proving to be an energy efficient solution due to higher thermal capacity of cooling fluid especially for the buildings that require individual zone controls and where the latent loads are moderate. The Conventional air conditioners work at very low temperature i.e.5-8 c (refrigerant evaporator inlet) while the radiant cooling systems, also referred as high temperature cooling system, work at high temperatures i.e. 14-18 c. The radiant cooling systems can maintain lower MRT (Mean Radiant Temperature) as ceiling panels maintain uniform temperature gradient inside room and provide higher human comfort. The radiant cooling systems are relatively new systems and their operation and energy savings potential are not quantified for a large number of buildings and operational parameters. Moreover, there are only limited numbers of whole building simulation studies have been carried out for these systems to have a full confidence in the capability of modelling tools to simulate these systems and predict the impact of various operating parameters. Theoretically, savings achieve due to higher temperature set point of chilled water, which reduces chiller-running time. However, conventional air conditioner runs continuously to maintain requisite temperature. In this paper, experimental study for performance evaluation of radiant cooling system carried out on system installed at Malaviya National Institute of Technology Jaipur. This paper quantifies the energy savings opportunities and effective temperature by radiant cooling system at different chilled water flow rates and temperature range. The data collected/ analysed through experimental study will used for calibration and validation of system model of building prepared in building performance simulation software. This validated model used for exploring optimized combinations of key parameters for composite climate. These optimized combinations will used in formulation of radiant cooling system

Radiant exchange in partially specular architectural environments

Science.gov (United States)

Beamer, C. Walter; Muehleisen, Ralph T.

2003-10-01

The radiant exchange method, also known as radiosity, was originally developed for thermal radiative heat transfer applications. Later it was used to model architectural lighting systems, and more recently it has been extended to model acoustic systems. While there are subtle differences in these applications, the basic method is based on solving a system of energy balance equations, and it is best applied to spaces with mainly diffuse reflecting surfaces. The obvious drawback to this method is that it is based around the assumption that all surfaces in the system are diffuse reflectors. Because almost all architectural systems have at least some partially specular reflecting surfaces in the system it is important to extend the radiant exchange method to deal with this type of surface reflection. [Work supported by NSF.

Relationship of core exit-temperature noise to thermal-hydraulic conditions in PWRs

International Nuclear Information System (INIS)

Sweeney, F.J.; Upadhyaya, B.R.

1983-01-01

Core exit thermocouple temperature noise and neutron detector noise measurements were performed at the Loss of Fluid Test Facility (LOFT) reactor and a Westinghouse, 1148 MW(e) PWR to relate temperature noise to core thermal-hydraulic conditions. The noise analysis results show that the RMS of the temperature noise increases linearly with increasing core δT at LOFT and the commercial PWR. Out-of-core test loop temperature noise has shown similar behavior. The phase angle between core exit temperature noise and in-core or ex-core neutron noise is directly related to the core coolant flow velocity. However, if the thermocouple response time is slow, compared to the coolant transit time between the sensors, velocities inferred from the phase angle are lower than measured coolant flow velocities

Solar radiation and cooling load calculation for radiant systems: Definition and evaluation of the Direct Solar Load

DEFF Research Database (Denmark)

Causone, Francesco; Corgnati, Stefano P.; Filippi, Marco

2010-01-01

The study of the influence of solar radiation on the built environment is a basic issue in building physics and currently it is extremely important because glazed envelopes are widely used in contemporary architecture. In the present study, the removal of solar heat gains by radiant cooling systems...... is investigated. Particular attention is given to the portion of solar radiation converted to cooling load, without taking part in thermal absorption phenomena due to the thermal mass of the room. This specific component of the cooling load is defined as the Direct Solar Load. A simplified procedure to correctly...... calculate the magnitude of the Direct Solar Load in cooling load calculations is proposed and it is implemented with the Heat Balance method and the Radiant Time Series method. The F ratio of the solar heat gains directly converted to cooling load, in the case of a low thermal mass radiant ceiling...

Electric radiant heating : a hot profitable idea

Energy Technology Data Exchange (ETDEWEB)

Lemieux, G. [Britech Corp., Toronto, ON (Canada)

2006-09-15

Due to the high cost of heating oil, natural gas and propane, floor mounted radiant heating systems are now proving to be a cost effective method of heating homes. The systems provide evenly distributed heat across the entire floor area. Unlike hydronic floor systems, radiant floor systems require no maintenance, and are easy to control because no mechanical rooms or boilers are required. The system is comprised of a series of resistant heating cables, a thermostat, and a solid state relay. The cables are installed in a poured concrete pad. Separate temperature control devices are used to heat individual areas of floorspace. Building automation systems can also control the heating system by using simple ambient air- and floor-mounted sensors in conjunction with relays to energize the heating cables. The cost of thermostats and heating cables to heat a standard 2000 square foot home are estimated at $9000.00, with an additional 64 hours of installation costs. It was noted that the systems may prove to be less costly in the long-term than hydronic systems, which require additional boilers, pumps and water treatments. Electric radiant heating can be an even more cost-effective application when used with thermal storage heating applications that use lower-cost off-peak electricity to generate and store heat in concrete floor slabs or ceramic bricks contained in insulated cabinets. It was concluded that radiant heating systems are a viable and cost-effective alternative to expensive hydronic systems, which are costly to install and maintain. 4 figs.

A METHOD FOR EVALUATION OF NON-UNIFORM RADIANT-CONVECTIVE LOAD ON HUMAN BODY DURING MENTAL WORK

Directory of Open Access Journals (Sweden)

Lenka Prokšová Zuská

2017-10-01

Full Text Available The objective of this study was to develop a documentation for the amendment of the microclimatic part of the Czech Government Regulation, particularly in a non-uniform radiant-convective load evaluation. Changes in regulation were made based on experimental data obtained on a group of experimental individuals in a climatic chamber. One of the objectives of the climatic chamber experiments was to evaluate whether there was a possibility to use an alternative method, which utilizes a new value – stereotemperature, for the assessment. A group of 24 women was exposed to a non-uniform radiant-convective load in a climatic chamber for 1 hour during their computer work. Measurements were divided according to the globe temperature into 3 stages. The physical parameters of air were continuously measured: the air temperature, globe temperature, air velocity, radiant temperature, relative humidity, stereotemperature and physiological parameters. Thermal sensations of experimental subjects were expressed in the seven-point scale according to EN ISO 7730. The thermal sensation correlated very well with the difference of stereotemperature and the globe temperature. The stereotemperature correlated very well with the radiant temperature. In this work, the composed equations were used to develop the limit values for the thermal stress evaluation in the uniform and non-uniform thermal environment at workplaces. It is possible to determine how the body of an exposed person perceives the non-uniform climatic conditions in the indoor environment, by adding the stereotemperature to government regulations.

Mathematical modelling, variational formulation and numerical simulation of the energy transfer process in a gray plate in the presence of a thermal radiant source

International Nuclear Information System (INIS)

Gama, R.M.S. da.

1992-05-01

The energy transfer process in a gray, opaque and rigid plate, heated by an external thermal radiant source, is considered. The source is regarded as a spherical black body, with radius a (a → 0) and uniform heat generation, placed above the plate. A mathematical model is constructed, assuming that the heat transfer from/to the plate takes place by thermal radiation. The obtained mathematical model is nonlinear. Is presented a suitable variational principle which is employed for simulating some particular cases. (author)

Load calculations of radiant cooling systems for sizing the plant

DEFF Research Database (Denmark)

Bourdakis, Eleftherios; Kazanci, Ongun Berk; Olesen, Bjarne W.

2015-01-01

The aim of this study was, by using a building simulation software, to prove that a radiant cooling system should not be sized based on the maximum cooling load but at a lower value. For that reason six radiant cooling models were simulated with two control principles using 100%, 70% and 50......% of the maximum cooling load. It was concluded that all tested systems were able to provide an acceptable thermal environment even when the 50% of the maximum cooling load was used. From all the simulated systems the one that performed the best under both control principles was the ESCS ceiling system. Finally...... it was proved that ventilation systems should be sized based on the maximum cooling load....

Influencia del tiempo de explotación del Láser de CO2 y la cantidad de ventiladores del Sistema de Enfriamiento sobre la estabilidad del flujo radiante a la salida del Sistema Láser SYNRAD 48-2. // The Influences of the time of exploitation of the Laser o

Directory of Open Access Journals (Sweden)

V. Ramirez Chi

2002-09-01

Full Text Available En el diseño de un Sistema Láser para ser utilizado con fines médicos, un aspecto a tener en cuenta por su importancia es lagarantía de lograr un Sistema de Ventilación que implique mantener estable el flujo radiante de láser a la salida del equipodurante el período de explotación. En el Centro Nacional de Investigaciones Científicas (CENIC se han hechoinvestigaciones en estos equipos de Sistemas Láser con el objetivo de determinar en que medida influyen la cantidad deventiladores dispuestos sobre el flujo radiante del láser a la salida del equipo de Láser de CO2 y el tiempo de explotacióndel equipo sobre la estabilidad del flujo radiante del láser de salida. Mediante la modelación, la simulación, el Diseño deExperimento y métodos estadísticos se determinó que el tiempo de explotación del equipo durante cada intervenciónmédica y la cantidad de ventiladores implican una influencia significativa sobre la estabilidad del flujo radiante de salida.Esta investigación se llevó a cabo en el equipo de Láser de CO2 SYNRAD 48-2 y se empleó en la misma el programa decomputación para el Diseño de Experimentos Statgrafics-Plus.Palabras claves: Láser, flujo radiante.____________________________________________________________________AbstractIn the design of a Laser System/s to be used with ends doctors, an aspect to keep in mind for its importance is the guaranteeof achieving a System of Ventilation that implies to maintain stable the radiant flow of exit of the Laser during the periodof exploitation. In the CENIC investigations have been made in these Laser System/s with the objective of determining inthat measured they influence the quantity of willing fans about the radiant flow of exit of the Laser of CO2 and the time ofexploitation of the Laser about the stability of the radiant flow of exit. By means of the modelación, the simulation, theDesign of Experiment and statistical methods were determined that the time of

Linearization of the interaction principle: Analytic Jacobians in the 'Radiant' model

International Nuclear Information System (INIS)

Spurr, R.J.D.; Christi, M.J.

2007-01-01

In this paper we present a new linearization of the Radiant radiative transfer model. Radiant uses discrete ordinates for solving the radiative transfer equation in a multiply-scattering anisotropic medium with solar and thermal sources, but employs the adding method (interaction principle) for the stacking of reflection and transmission matrices in a multilayer atmosphere. For the linearization, we show that the entire radiation field is analytically differentiable with respect to any surface or atmospheric parameter for which we require Jacobians (derivatives of the radiance field). Derivatives of the discrete ordinate solutions are based on existing methods developed for the LIDORT radiative transfer models. Linearization of the interaction principle is completely new and constitutes the major theme of the paper. We discuss the application of the Radiant model and its linearization in the Level 2 algorithm for the retrieval of columns of carbon dioxide as the main target of the Orbiting Carbon Observatory (OCO) mission

Energy flow and thermal comfort in buildings: Comparison of radiant and air-based heating & cooling systems

DEFF Research Database (Denmark)

Le Dréau, Jérôme

is based on both radiation and convection. This thesis focuses on characterizing the heat transfer from the terminal towards the space and on the parameters influencing the effectiveness of terminals. Therefore the comfort conditions and energy consumption of four types of terminals (active chilled beam...... losses, and an air-based terminal might be more energy-efficient than a radiant terminal (in terms of delivered energy). Regarding comfort, a similar global level has been observed for the radiant and air-based terminals in both numerical and experimental investigations. But the different terminals did...... not achieve the same uniformity in space. The active chilled beam theoretically achieves the most uniform comfort conditions (when disregarding the risk of draught), followed by the radiant ceiling. The least uniform conditions were obtained with the cooled floor due to large differences between the sitting...

Energy flow and thermal comfort in buildings: Comparison of radiant and air-based heating & cooling systems

DEFF Research Database (Denmark)

Le Dréau, Jérôme

Heating and cooling terminals can be classified in two main categories: convective terminals (e.g air conditioning, active chilled beam, fan coil) and radiant terminals. The two terminals have different modes of heat transfer: the first one is mainly based on convection, whereas the second one...... is based on both radiation and convection. This thesis focuses on characterizing the heat transfer from the terminal towards the space and on the parameters influencing the effectiveness of terminals. Therefore the comfort conditions and energy consumption of four types of terminals (active chilled beam...... losses, and an air-based terminal might be more energy-efficient than a radiant terminal (in terms of delivered energy). Regarding comfort, a similar global level has been observed for the radiant and air-based terminals in both numerical and experimental investigations. But the different terminals did...

Design of outdoor urban spaces for thermal comfort

Science.gov (United States)

Harriet J. Plumley

1977-01-01

Microclimates in outdoor urban spaces may be modified by controlling the wind and radiant environments in these spaces. Design guidelines were developed to specify how radiant environments may be selected or modified to provide conditions for thermal comfort. Fanger's human-thermal-comfort model was used to determine comfortable levels of radiant-heat exchange for...

Experimental and Numerical Study of the Radiant Induction-Unit and the Induction Radiant Air-Conditioning System

Directory of Open Access Journals (Sweden)

Qiang Si

2016-12-01

Full Text Available In this paper we proposed the novel air-conditioning system which combined induction ventilation and radiant air-conditioning. The indoor terminal device is the radiant induction-unit (RIDU. The RIDU is the induction unit combined with the pore radiant panel on which the copper pipes with rigid aluminum diffusion fins are installed. The two-stage evaporator chiller with the non-azeotropic mixture refrigerant is utilized in the system to reduce the initial investment in equipment. With the performance test and the steady state heat transfer model based on the theory of radiative heat transfer, the relationship between the induction ratio of the RIDU and the characteristic of the air supply was studied. Based on this, it is verified that the RIDU has a lower dew-point temperature and better anti-condensation performance than a traditional plate-type radiant panel. The characteristics of the radiation and convection heat transfer of the RIDU were studied. The total heat exchange of the RIDU can be 16.5% greater than that of the traditional plate-type radiant terminal.

Experimental and numerical analysis of air and radiant cooling systems in offices

DEFF Research Database (Denmark)

Corgnati, S. P.; Perino, M.; Fracastoro, G. V.

2009-01-01

This paper analyses office cooling systems based on all air mixing ventilation systems alone or coupled with radiant ceiling panels. This last solution may be effectively applied to retrofit all air systems that are no longer able to maintain a suitable thermal comfort in the indoor environment, ...

Radiant Heating and Cooling Systems. Part one

DEFF Research Database (Denmark)

Kim, Kwan Woo; Olesen, Bjarne W.

2015-01-01

The use of radiant heating systems has several thousand years of history.1,2 The early stage of radiant system application was for heating purposes, where hot air from flue gas (cooking, fires) was circulated under floors or in walls. After the introduction of plastic piping water-based radiant...

A RADIANT AIR-CONDITIONING SYSTEM USING SOLAR-DRIVEN

Directory of Open Access Journals (Sweden)

S. A. ABDALLA

2006-12-01

Full Text Available Every air-conditioning system needs some fresh air to provide adequate ventilation air required to remove moisture, gases like ammonia and hydrogen sulphide, disease organisms, and heat from occupied spaces. However, natural ventilation is difficult to control because urban areas outside air is often polluted and cannot be supplied to inner spaces before being filtered. Besides the high electrical demand of refrigerant compression units used by most air-conditioning systems, and fans used to transport the cool air through the thermal distribution system draw a significant amount of electrical energy in comparison with electrical energy used by the building thermal conditioning systems. Part of this electricity heats the cooled air; thereby add to the internal thermal cooling peak load. In addition, refrigerant compression has both direct and indirect negative effects on the environment on both local and global scales. In seeking for innovative air-conditioning systems that maintain and improve indoor air quality under potentially more demanding performance criteria without increasing environmental impact, this paper presents radiant air-conditioning system which uses a solar-driven liquid desiccant evaporative cooler. The paper describes the proposed solar-driven liquid desiccant evaporative cooling system and the method used for investigating its performance in providing cold water for a radiant air-conditioning system in Khartoum (Central Sudan. The results of the investigation show that the system can operate in humid as well as dry climates and that employing such a system reduces air-conditioning peak electrical demands as compared to vapour compression systems.

Validation of the uncertainty budget for soft X-ray radiant power measurement using a cryogenic radiometer

CERN Document Server

Rabus, H; Scholze, F; Thornagel, R; Ulm, G

2002-01-01

The cryogenic radiometer SYRES, a thermal detector based on the electrical substitution principle, has been used as the primary detector standard for radiant power measurement in the ultraviolet, vacuum ultraviolet and soft X-ray spectral ranges. In order to investigate the possibility of radiant energy being deposited in its absorber cavity without being transformed into heat when detecting soft X-rays, SYRES has been directly compared with the electron storage ring BESSY 1, a primary radiometric source standard of calculable spectral radiant power. To this end, the integral radiant power emitted by the storage ring,into a solid angle defined by a high-precision aperture was measured with SYRES. The experiments were conducted at two nominal energies of the circulating electrons, 800 MeV and 340 MeV, to study the influence of the different spectral distributions of the synchrotron radiation. For the original graphite-coated cavity absorber, significant discrepancies were found which could be traced back to th...

Thermal inertia and radiating average Temperature. A brief analysis of some causes of discomfort; Inercia Termica y Temperatura media radiante. Un breve analisis de algunas causas de disconfort

Energy Technology Data Exchange (ETDEWEB)

Arroba, M.

2008-07-01

Radiant average temperature in walls is as important as dry air temperature to achieve thermal comfort of users of a local. An excessive discrepancy between these levels, or an asymmetric distribution of the surface temperature of fences, may cause localized thermal discomfort, an effect impossible to compensate by rising dry air temperature. Thermal inertia and its concentration must be properly studied in order to handle this parameters, inside or outside the building, on both sides of the cladding or none depending on the weather, the bio climatic strategies used, heating and air conditioning systems and planned use of the building. (Author)

Cooling load calculation by the radiant time series method - effect of solar radiation models

Energy Technology Data Exchange (ETDEWEB)

Costa, Alexandre M.S. [Universidade Estadual de Maringa (UEM), PR (Brazil)], E-mail: amscosta@uem.br

2010-07-01

In this work was analyzed numerically the effect of three different models for solar radiation on the cooling load calculated by the radiant time series' method. The solar radiation models implemented were clear sky, isotropic sky and anisotropic sky. The radiant time series' method (RTS) was proposed by ASHRAE (2001) for replacing the classical methods of cooling load calculation, such as TETD/TA. The method is based on computing the effect of space thermal energy storage on the instantaneous cooling load. The computing is carried out by splitting the heat gain components in convective and radiant parts. Following the radiant part is transformed using time series, which coefficients are a function of the construction type and heat gain (solar or non-solar). The transformed result is added to the convective part, giving the instantaneous cooling load. The method was applied for investigate the influence for an example room. The location used was - 23 degree S and 51 degree W and the day was 21 of January, a typical summer day in the southern hemisphere. The room was composed of two vertical walls with windows exposed to outdoors with azimuth angles equals to west and east directions. The output of the different models of solar radiation for the two walls in terms of direct and diffuse components as well heat gains were investigated. It was verified that the clear sky exhibited the less conservative (higher values) for the direct component of solar radiation, with the opposite trend for the diffuse component. For the heat gain, the clear sky gives the higher values, three times higher for the peek hours than the other models. Both isotropic and anisotropic models predicted similar magnitude for the heat gain. The same behavior was also verified for the cooling load. The effect of room thermal inertia was decreasing the cooling load during the peak hours. On the other hand the higher thermal inertia values are the greater for the non peak hours. The effect

Validation of the uncertainty budget for soft X-ray radiant power measurement using a cryogenic radiometer

International Nuclear Information System (INIS)

Rabus, H.; Klein, R.; Scholze, F.; Thornagel, R.; Ulm, G.

2002-01-01

The cryogenic radiometer SYRES, a thermal detector based on the electrical substitution principle, has been used as the primary detector standard for radiant power measurement in the ultraviolet, vacuum ultraviolet and soft X-ray spectral ranges. In order to investigate the possibility of radiant energy being deposited in its absorber cavity without being transformed into heat when detecting soft X-rays, SYRES has been directly compared with the electron storage ring BESSY 1, a primary radiometric source standard of calculable spectral radiant power. To this end, the integral radiant power emitted by the storage ring,into a solid angle defined by a high-precision aperture was measured with SYRES. The experiments were conducted at two nominal energies of the circulating electrons, 800 MeV and 340 MeV, to study the influence of the different spectral distributions of the synchrotron radiation. For the original graphite-coated cavity absorber, significant discrepancies were found which could be traced back to the ablation of the graphite coating from the copper cavity body. In the case of the new gold-coated cavity absorber, the calculated and measured values of the radiant power agreed in all experiments within the combined relative uncertainties of typically 2.5 x 10 -3 (k = 1). (author)

Electric radiant heating or, why are plumbers getting our work?

Energy Technology Data Exchange (ETDEWEB)

Lemieux, G. [Britech, Toronto, ON (Canada)

2009-02-15

Electric radiant heating (ERH) technologies are now being installed in floors as a means of reducing heating costs. The radiant installations have seen a large increase in sales over the last decade, and are now being used in commercial applications. Sales of hydronic ERH systems have increased by 24 per cent over the last year. ERH systems are energy efficient and do not cause drafts. The systems consist of resistant heating cables installed within the floors of a room. The cables are supplied as loose cables and tracks with predetermined spacings or rugged, heavier cable that can be stapled onto wooden subfloors. Program temperature setbacks can be applied on a room-by-room basis. Electric thermal storage systems allow building owners to store heat in the floors and are ideal for use in combination with time-of-use electric metering. Some electric utilities are now promoting the use of electric thermal storage in order to reduce demand during peak times. Thermostats used with the systems should have floor sensors and ambient air sensors to control space heating in conjunction with the floor sensor. It was concluded that electrical contractors who gain knowledge in the application and installation of the systems will tap into a growing revenue stream. 5 figs.

Electric radiant heating or, why are plumbers getting our work?

International Nuclear Information System (INIS)

Lemieux, G.

2009-01-01

Electric radiant heating (ERH) technologies are now being installed in floors as a means of reducing heating costs. The radiant installations have seen a large increase in sales over the last decade, and are now being used in commercial applications. Sales of hydronic ERH systems have increased by 24 per cent over the last year. ERH systems are energy efficient and do not cause drafts. The systems consist of resistant heating cables installed within the floors of a room. The cables are supplied as loose cables and tracks with predetermined spacings or rugged, heavier cable that can be stapled onto wooden subfloors. Program temperature setbacks can be applied on a room-by-room basis. Electric thermal storage systems allow building owners to store heat in the floors and are ideal for use in combination with time-of-use electric metering. Some electric utilities are now promoting the use of electric thermal storage in order to reduce demand during peak times. Thermostats used with the systems should have floor sensors and ambient air sensors to control space heating in conjunction with the floor sensor. It was concluded that electrical contractors who gain knowledge in the application and installation of the systems will tap into a growing revenue stream. 5 figs

Radiant heat loss, an unexploited path for heat stress reduction in shaded cattle.

Science.gov (United States)

Berman, A; Horovitz, T

2012-06-01

Reducing thermal radiation on shaded animals reduces heat stress independently of other means of stress relief. Radiant heat exchange was estimated as a function of climate, shade structure, and animal density. Body surface portion exposed to radiant sources in shaded environments was determined by geometrical relations to determine angles of view of radiation sources (roof underside, sky, sun-exposed ground, shaded ground) on the animal's surface. The relative representation of environment radiation sources on the body surface was determined. Animal thermal radiation balance was derived from radiant heat gained from radiation sources (including surrounding animals) and that lost from the animal surface. The animal environment was assumed to have different shade dimensions and temperatures. These were summed to the radiant heat balance of the cow. The data formed served to estimate the effect of changes in intensity of radiation sources, roof and shaded surface dimensions, and animal density on radiant heat balance (Rbal) of cattle. Roof height effect was expressed by effect of roof temperature on Rbal. Roof underside temperature (35 to 75°C) effect on Rbal was reduced by roof height. If roof height were 4m, an increase in its underside temperature from 35 to 75°C would increase mean Rbal from -63 to -2 W·m⁻², whereas if roof height were 10 m, Rbal would only increase from -99 to -88 W·m⁻². A hot ground temperature increase from 35 to 65°C reduced mean Rbal heat loss from -45 to 3 W·m⁻². Increasing the surface of the shaded area had only a minor effect on Rbal and on the effect of hot ground on Rbal. Increasing shade roof height reduced the effect of roof temperature on Rbal to minor levels when height was > 8m. Increasing the roof height from 4 to 10 m decreased Rbal from -32 to -94 W·m⁻². Increasing indirect radiation from 100 to 500 W·m⁻² was associated with an increase in Rbal from -135 to +23 W·m⁻². Their combined effects were lower

Inverse optimal design of the radiant heating in materials processing and manufacturing

Science.gov (United States)

Fedorov, A. G.; Lee, K. H.; Viskanta, R.

1998-12-01

Combined convective, conductive, and radiative heat transfer is analyzed during heating of a continuously moving load in the industrial radiant oven. A transient, quasi-three-dimensional model of heat transfer between a continuous load of parts moving inside an oven on a conveyor belt at a constant speed and an array of radiant heaters/burners placed inside the furnace enclosure is developed. The model accounts for radiative exchange between the heaters and the load, heat conduction in the load, and convective heat transfer between the moving load and oven environment. The thermal model developed has been used to construct a general framework for an inverse optimal design of an industrial oven as an example. In particular, the procedure based on the Levenberg-Marquardt nonlinear least squares optimization algorithm has been developed to obtain the optimal temperatures of the heaters/burners that need to be specified to achieve a prescribed temperature distribution of the surface of a load. The results of calculations for several sample cases are reported to illustrate the capabilities of the procedure developed for the optimal inverse design of an industrial radiant oven.

Calculation codes for radiant heat transfers; Les codes de calcul de rayonnement thermique

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-31

This document reports on 12 papers about computerized simulation and modeling of radiant heat transfers and fluid flows in various industrial and domestic situations: space heating, metal industry (furnaces, boilers..), aerospace industry (turbojet engines, combustion chambers) etc.. This workshop was organized by the ``radiation`` section of the French society of thermal engineers. (J.S.)

Calculation codes for radiant heat transfers; Les codes de calcul de rayonnement thermique

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-31

This document reports on 12 papers about computerized simulation and modeling of radiant heat transfers and fluid flows in various industrial and domestic situations: space heating, metal industry (furnaces, boilers..), aerospace industry (turbojet engines, combustion chambers) etc.. This workshop was organized by the ``radiation`` section of the French society of thermal engineers. (J.S.)

Effect of radiant heat transfer on the performance of high temperature heat exchanger

International Nuclear Information System (INIS)

Mori, Yasuo; Hijikata, Kunio; Yamada, Yukio

1975-01-01

The development of high temperature gas-cooled reactors is motivated by the consideration of the application of nuclear heat for industrial uses or direct steelmaking and chemical processes. For these purposes, reliable and efficient heat exchangers should be developed. This report analyzes the effect of radiant heat transfer on the performance of high temperature heat exchangers. The heat transfer model is as follows: the channel composed with two parallel adiabatic walls is divided with one parallel plate between the walls. Non-radiative fluid flows in the two separated channels in opposite direction. Heat transfer equations for this system were obtained, and these equations were solved by some approximate method and numerical analysis. The effect of radiation on heat transfer became larger as the radiant heat transfer between two walls was larger. In the heat exchangers of counter flow type, the thermal efficiency is controlled with three parameters, namely radiation-convection parameter, Stanton number and temperature difference. The thermal efficiency was larger with the increase of these parameters. (Iwase, T.)

Dynamic heat transfer modeling and parametric study of thermoelectric radiant cooling and heating panel system

International Nuclear Information System (INIS)

Luo, Yongqiang; Zhang, Ling; Liu, Zhongbing; Wang, Yingzi; Wu, Jing; Wang, Xiliang

2016-01-01

Highlights: • Dynamic model of thermoelectric radiant panel system is established. • The internal parameters of thermoelectric module are dynamically calculated in simulation. • Both artificial neural networks model and system model are verified through experiment data. • Optimized system structure is obtained through parametric study. - Abstract: Radiant panel system can optimize indoor thermal comfort with lower energy consumption. The thermoelectric radiant panel (TERP) system is a new and effective prototype of radiant system using thermoelectric module (TEM) instead of conventional water pipes, as heat source. The TERP can realize more stable and easier system control as well as lower initial and operative cost. In this study, an improved system dynamic model was established by combining analytical system model and artificial neural networks (ANN) as well as the dynamic calculation functions of internal parameters of TEM. The double integral was used for the calculation of surface average temperature of TERP. The ANN model and system model were in good agreement with experiment data in both cooling and heating mode. In order to optimize the system design structure, parametric study was conducted in terms of the thickness of aluminum panel and insulation, as well as the arrangement of TEMs on the surface of radiant panel. It was found through simulation results that the optimum thickness of aluminum panel and insulation are respectively around 1–2 mm and 40–50 mm. In addition, TEMs should be uniformly installed on the surface of radiant panel and each TEM should stand at the central position of a square-shaped typical region with length around 0.387–0.548 m.

Finite-elements modeling of radiant heat transfers between mobile surfaces; Modelisation par elements finis de transferts radiatifs entre surfaces mobiles

Energy Technology Data Exchange (ETDEWEB)

Daurelle, J V; Cadene, V; Occelli, R [Universite de Provence, 13 - Marseille (France)

1997-12-31

In the numerical modeling of thermal industrial problems, radiant heat transfers remain difficult to take into account and require important computer memory and long computing time. These difficulties are enhanced when radiant heat transfers are coupled with finite-elements diffusive heat transfers because finite-elements architecture is complex and requires a lot of memory. In the case of radiant heat transfers along mobile boundaries, the methods must be optimized. The model described in this paper concerns the radiant heat transfers between diffuse grey surfaces. These transfers are coupled with conduction transfers in the limits of the diffusive opaque domain. 2-D and 3-D geometries are analyzed and two configurations of mobile boundaries are considered. In the first configuration, the boundary follows the deformation of the mesh, while in the second, the boundary moves along the fixed mesh. Matter displacement is taken into account in the term of transport of the energy equation, and an appropriate variation of the thermophysical properties of the transition elements between the opaque and transparent media is used. After a description of the introduction of radiative limit conditions in a finite-elements thermal model, the original methods used to optimize calculation time are explained. Two examples of application illustrate the approach used. The first concerns the modeling of radiant heat transfers between fuel rods during a reactor cooling accident, and the second concerns the study of heat transfers inside the air-gap of an electric motor. The method of identification of the mobile surface on the fixed mesh is described. (J.S.) 12 refs.

Finite-elements modeling of radiant heat transfers between mobile surfaces; Modelisation par elements finis de transferts radiatifs entre surfaces mobiles

Energy Technology Data Exchange (ETDEWEB)

Daurelle, J.V.; Cadene, V.; Occelli, R. [Universite de Provence, 13 - Marseille (France)

1996-12-31

In the numerical modeling of thermal industrial problems, radiant heat transfers remain difficult to take into account and require important computer memory and long computing time. These difficulties are enhanced when radiant heat transfers are coupled with finite-elements diffusive heat transfers because finite-elements architecture is complex and requires a lot of memory. In the case of radiant heat transfers along mobile boundaries, the methods must be optimized. The model described in this paper concerns the radiant heat transfers between diffuse grey surfaces. These transfers are coupled with conduction transfers in the limits of the diffusive opaque domain. 2-D and 3-D geometries are analyzed and two configurations of mobile boundaries are considered. In the first configuration, the boundary follows the deformation of the mesh, while in the second, the boundary moves along the fixed mesh. Matter displacement is taken into account in the term of transport of the energy equation, and an appropriate variation of the thermophysical properties of the transition elements between the opaque and transparent media is used. After a description of the introduction of radiative limit conditions in a finite-elements thermal model, the original methods used to optimize calculation time are explained. Two examples of application illustrate the approach used. The first concerns the modeling of radiant heat transfers between fuel rods during a reactor cooling accident, and the second concerns the study of heat transfers inside the air-gap of an electric motor. The method of identification of the mobile surface on the fixed mesh is described. (J.S.) 12 refs.

Modeling of hydronic radiant cooling of a thermally homeostatic building using a parametric cooling tower

International Nuclear Information System (INIS)

Ma, Peizheng; Wang, Lin-Shu; Guo, Nianhua

2014-01-01

Highlights: • Investigated cooling of thermally homeostatic buildings in 7 U.S. cities by modeling. • Natural energy is harnessed by cooling tower to extract heat for building cooling. • Systematically studied possibility and conditions of using cooling tower in buildings. • Diurnal ambient temperature amplitude is taken into account in cooling tower cooling. • Homeostatic building cooling is possible in locations with large ambient T amplitude. - Abstract: A case is made that while it is important to mitigate dissipative losses associated with heat dissipation and mechanical/electrical resistance for engineering efficiency gain, the “architect” of energy efficiency is the conception of best heat extraction frameworks—which determine the realm of possible efficiency. This precept is applied to building energy efficiency here. Following a proposed process assumption-based design method, which was used for determining the required thermal qualities of building thermal autonomy, this paper continues this line of investigation and applies heat extraction approach investigating the extent of building partial homeostasis and the possibility of full homeostasis by using cooling tower in one summer in seven selected U.S. cities. Cooling tower heat extraction is applied parametrically to hydronically activated radiant-surfaces model-buildings. Instead of sizing equipment as a function of design peak hourly temperature as it is done in heat balance design-approach of selecting HVAC equipment, it is shown that the conditions of using cooling tower depend on both “design-peak” daily-mean temperature and the distribution of diurnal range in hourly temperature (i.e., diurnal temperature amplitude). Our study indicates that homeostatic building with natural cooling (by cooling tower alone) is possible only in locations of special meso-scale climatic condition such as Sacramento, CA. In other locations the use of cooling tower alone can only achieve homeostasis

Radiant non-catalytic recuperative reformer

Energy Technology Data Exchange (ETDEWEB)

Khinkis, Mark J.; Kozlov, Aleksandr P.

2017-10-31

A radiant, non-catalytic recuperative reformer has a flue gas flow path for conducting hot exhaust gas from a thermal process and a reforming mixture flow path for conducting a reforming mixture. At least a portion of the reforming mixture flow path is positioned adjacent to the flue gas flow path to permit heat transfer from the hot exhaust gas to the reforming mixture. The reforming mixture flow path contains substantially no material commonly used as a catalyst for reforming hydrocarbon fuel (e.g., nickel oxide, platinum group elements or rhenium), but instead the reforming mixture is reformed into a higher calorific fuel via reactions due to the heat transfer and residence time. In a preferred embodiment, a portion of the reforming mixture flow path is positioned outside of flue gas flow path for a relatively large residence time.

Mathematical Modeling of the Thermal State of an Isothermal Element with Account of the Radiant Heat Transfer Between Parts of a Spacecraft

Science.gov (United States)

Alifanov, O. M.; Paleshkin, A. V.; Terent‧ev, V. V.; Firsyuk, S. O.

2016-01-01

A methodological approach to determination of the thermal state at a point on the surface of an isothermal element of a small spacecraft has been developed. A mathematical model of heat transfer between surfaces of intricate geometric configuration has been described. In this model, account was taken of the external field of radiant fluxes and of the differentiated mutual influence of the surfaces. An algorithm for calculation of the distribution of the density of the radiation absorbed by surface elements of the object under study has been proposed. The temperature field on the lateral surface of the spacecraft exposed to sunlight and on its shady side has been calculated. By determining the thermal state of magnetic controls of the orientation system as an example, the authors have assessed the contribution of the radiation coming from the solar-cell panels and from the spacecraft surface.

Comparison of radiant and convective cooling of office room: effect of workstation layout

DEFF Research Database (Denmark)

Bolashikov, Zhecho Dimitrov; Melikov, Arsen Krikor; Rezgals, Lauris

2014-01-01

and compared. The room was furnished with two workstations, two laptops and two thermal manikins resembling occupants. Two heat load levels, design (65 W/m2) and usual (39 W/m2), were generated by adding heat from warm panels simulating solar radiation. Two set-ups were studied: occupants sitting......The impact of heat source location (room layout) on the thermal environment generated in a double office room with four cooling ventilation systems - overhead ventilation, chilled ceiling with overhead ventilation, active chilled beam and active chilled beam with radiant panels was measured...

Use of local convective and radiant cooling at warm environment

DEFF Research Database (Denmark)

Melikov, Arsen Krikor; Krejcirikova, Barbora; Kaczmarczyk, Jan

2012-01-01

The effect of four local cooling devices (convective, radiant and combined) on SBS symptoms reported by 24 subjects at 28 ˚C and 50% RH was studied. The devices studied were: (1) desk cooling fan, (2) personalized ventilation providing clean air, (3) two radiant panels and (4) two radiant panels...... and with radiant panel with attached fans, which also helped people to feel less fatigue. The SBS symptoms increased the most when the cooling fan, generating movement of polluted room air, was used....

Thermal model of spent fuel transport cask

International Nuclear Information System (INIS)

Ahmed, E.E.M.; Rahman, F.A.; Sultan, G.F.; Khalil, E.E.

1996-01-01

The investigation provides a theoretical model to represent the thermal behaviour of the spent fuel elements when transported in a dry shipping cask under normal transport conditions. The heat transfer process in the spent fuel elements and within the cask are modeled which include the radiant heat transfer within the cask and the heat transfer by thermal conduction within the spent fuel element. The model considers the net radiant method for radiant heat transfer process from the inner most heated element to the surrounding spent elements. The heat conduction through fuel interior, fuel-clad interface and on clad surface are also presented. (author) 6 figs., 9 refs

Radiant heat testing of the H1224A shipping/storage container

Energy Technology Data Exchange (ETDEWEB)

Harding, D.C.; Bobbe, J.G.; Stenberg, D.R.; Arviso, M.

1994-05-01

H1224A weapons containers have been used for years by the Departments of Energy and Defense to transport and store W78 warhead midsections. Although designed to protect the midsections only from low-energy impacts, a recent transportation risk assessment effort has identified a need to evaluate the container`s ability to protect weapons in more severe accident environments. Four radiant heat tests were performed: two each on an H1224A container (with a Mk12a Mod 6c mass mock-up midsection inside) and two on a low-cost simulated H1224A container (with a hollow Mk12 aeroshell midsections inside). For each unit tested, temperatures were recorded at numerous points throughout the container and midsection during a 4-hour 121{degrees}C (250{degrees}F) and 30-minute 1010{degrees}C (1850{degrees}F) radiant environment. Measured peak temperatures experienced by the inner walls of the midsections as a result of exposure to the high-temperature radiant environment ranged from 650{degrees} C to 980{degrees} C (1200{degrees} F to 1800{degrees}F) for the H1224A container and 770 {degrees} to 990 {degrees}C (1420{degrees} F to 1810{degrees}F) for the simulated container. The majority of both containers were completely destroyed during the high-temperature test. Temperature profiles will be used to benchmark analytical models and predict warhead midsection temperatures over a wide range of the thermal accident conditions.

Solar–terrestrial radiant-energy regimes and temperature anomalies of natural and artificial turfs

International Nuclear Information System (INIS)

Jim, C.Y.

2016-01-01

Highlights: • Solar and terrestrial radian energy regimes affect temperature response of sports turfs. • Adjacent natural and artificial turfs were monitored with replications on sunny days. • Artificial turf has meager albedo, low specific heat and moisture to augment warming. • Artificial turf surface and substrate reach 70 °C but cool down effectively at night. • Artificial turf may induce heat stress on athletes in hot summer afternoon. - Abstract: Artificial turf can develop unusually high surface temperature on hot sunny days. Solar and terrestrial radiant energy regimes as key determinants of thermal performance deserve detailed investigation. This study evaluated six components of the radiant-energy environment of a natural turf (NT) and a contiguous artificial turf (AT) sports fields in Hong Kong: direct solar, reflected solar, net solar, sky thermal, ground thermal, and net thermal. Temperature was monitored at five positions: air at 150 cm, 50 cm and 15 cm height, turf surface, and substrate. The experiment included four replications, namely two summer sunny days, and two duplicated instrument sets at each turf site. The two sites reacted very differently to the same intense daily sum of solar radiation input of 23.70 MW m −2 with 9 h of bright sunshine (>120 W m −2 ), and daily sum of sky thermal radiation input of 38.59 MW m −2 . The maximum direct solar radiation reached 976.1 W m −2 at 1245 h. NT albedo of 0.23 vis-à-vis AT of merely 0.073, and higher moisture content and specific heat of NT materials, presented critical differences. The hydrophobic and generally dry plastic (polyethylene) pile-fibers and black rubber-granule infill materials have low specific heat. Intense incoming shortwave and longwave radiation absorbed readily by AT materials raised turf surface temperature to 70.2 °C and substrate 69.3 °C, in comparison with <40 °C at NT. A cascading warming effect was triggered, beginning with low albedo, high net solar

Improvement on life and NO{sub x} discharge of radiant heat transfer tube heating system by the elasto-plasticity creep analysis; Dansosei kuripukaiseki ni yoru hosha dennetsukan kanetsu shisutemu no jumyo to NO{sub x} haishutsuryo no kaizen

Energy Technology Data Exchange (ETDEWEB)

Nakagawa, Futahiko; Ikaruda, Kunihiro; Abe, Yoshio; Arai, Norio

1999-06-05

Combustion thermal process using the radiant heat transfer tube has widely been applied as a heating method which separates the combustion atmosphere from the heating-e atmosphere in various heating furnace such as iron and steel industry. In this thermal process, in order to burn the fuel in tight space in radiant heat transfer service area, radiant heat transfer tube and burner life were short under high temperature and high-load combustion, and there was a problem that that and, burning characteristic such as NO{sub x} generation rate are improved was difficult. In this study, large temperature distribution by the combustion in the radiant heat transfer tube clarified that the life of the radiant heat transfer tube was shortened by elasto-plasticity creep analysis of the radiant heat transfer tube. Then, two steps combustion burner of the exhaust gas self recycling type was developed as a method for reducing the NO{sub x} generation rate, while the temperature distribution of the radiant heat transfer tube was equalized. As the result, it was possible to reduce over 20% in comparison with conventional two steps combustion burner, while radiant heat transfer tube and life of the burner are extended over the conventional double, in respect of the NO{sub x} generation rate. (translated by NEDO)

Numerical Simulation of the Thermal Process in a W-Shape Radiant Tube Burner

Science.gov (United States)

Wang, Yi; Li, Jiyong; Zhang, Lifeng; Ling, Haitao; Li, Yanlong

2014-07-01

In the current work, three-dimensional mathematical models were developed for the heat transfer and combustion in a W-shape radiant tube burner (RTB) and were solved using Fluent software (ANSYS Inc., Canonsburg, PA). The standard k- ɛ model, nonpremixed combustion model, and the discrete ordinate model were used for the modeling of turbulence, combustion, and radiant heat transfer, respectively. In addition, the NO x postprocessor was used for the prediction of the NO emission. A corresponding experiment was performed for the validation of mathematical models. The details of fluid flow, heat transfer, and combustion in the RTB were investigated. Moreover, the effect of the air/fuel ratio (A/F) and air staging on the performance of RTB was studied with the reference indexes including heat efficiency, maximum temperature difference on shell wall, and NO emission at the outlet. The results indicated that a low speed zone formed in the vicinity of the combustion chamber outlet, and there were two relative high-temperature zones in the RTB, one in combustion chamber that favored the flame stability and the other from the main flame in the RTB. The maximum temperature difference was 95.48 K. As the A/F increased, the temperature increased first and then decreased. As the ratio of the primary to secondary air increased, the recirculation zone at the outlet of combustion chamber shrank gradually to disappear, and the flame length was longer and the temperature in flame decreased correspondingly.

Radiant heating tests of several liquid metal heat-pipe sandwich panels

International Nuclear Information System (INIS)

Camarda, C.J.; Basiulis, A.

1983-08-01

Integral heat pipe sandwich panels, which synergistically combine the thermal efficiency of heat pipes and the structural efficiency of honeycomb sandwich construction, were conceived as a means of alleviating thermal stress problems in the Langley Scramjet Engine. Test panels which utilized two different wickable honeycomb cores, facesheets with screen mesh sintered to the internal surfaces, and a liquid metal working fluid (either sodium or potassium) were tested by radiant heating at various heat load levels. The heat pipe panels reduced maximum temperature differences by 31 percent with sodium working fluid and 45 percent with potassium working fluid. Results indicate that a heat pipe sandwich panel is a potential, simple solution to the engine thermal stress problem. Other interesting applications of the concept include: cold plates for electronic component and circuit card cooling, radiators for large space platforms, low distortion large area structures (e.g., space antennas) and laser mirrors

Phase-Change Thermal Energy Storage

Science.gov (United States)

1989-11-01

The goal of this program is to advance the engineering and scientific understanding of solar thermal technology and to establish the technology base from which private industry can develop solar thermal power production options for introduction into the competitive energy market. Solar thermal technology concentrates the solar flux using tracking mirrors or lenses onto a receiver where the solar energy is absorbed as heat and converted into electricity or incorporated into products as process heat. The two primary solar thermal technologies, central receivers and distributed receivers, employ various point and line-focus optics to concentrate sunlight. Current central receiver systems use fields of heliostats (two-axes tracking mirrors) to focus the sun's radiant energy onto a single, tower-mounted receiver. Point focus concentrators up to 17 meters in diameter track the sun in two axes and use parabolic dish mirrors or Fresnel lenses to focus radiant energy onto a receiver. Troughs and bowls are line-focus tracking reflectors that concentrate sunlight onto receiver tubes along their focal lines. Concentrating collector modules can be used alone or in a multimodule system. The concentrated radiant energy absorbed by the solar thermal receiver is transported to the conversion process by a circulating working fluid. Receiver temperatures range from 100 C in low-temperature troughs to over 1500 C in dish and central receiver systems.

Exit selection strategy in pedestrian evacuation simulation with multi-exits

International Nuclear Information System (INIS)

Yue Hao; Zhang Bin-Ya; Shao Chun-Fu; Xing Yan

2014-01-01

A mixed strategy of the exit selection in a pedestrian evacuation simulation with multi-exits is constructed by fusing the distance-based and time-based strategies through a cognitive coefficient, in order to reduce the evacuation imbalance caused by the asymmetry of exits or pedestrian layout, to find a critical density to distinguish whether the strategy of exit selection takes effect or not, and to analyze the exit selection results with different cognitive coefficients. The strategy of exit selection is embedded in the computation of the shortest estimated distance in a dynamic parameter model, in which the concept of a jam area layer and the procedure of step-by-step expending are introduced. Simulation results indicate the characteristics of evacuation time gradually varying against cognitive coefficient and the effectiveness of reducing evacuation imbalance caused by the asymmetry of pedestrian or exit layout. It is found that there is a critical density to distinguish whether a pedestrian jam occurs in the evacuation and whether an exit selection strategy is in effect. It is also shown that the strategy of exit selection has no effect on the evacuation process in the no-effect phase with a low density, and that evacuation time and exit selection are dependent on the cognitive coefficient and pedestrian initial density in the in-effect phase with a high density. (general)

Optimal design approach for heating irregular-shaped objects in three-dimensional radiant furnaces using a hybrid genetic algorithm-artificial neural network method

Science.gov (United States)

Darvishvand, Leila; Kamkari, Babak; Kowsary, Farshad

2018-03-01

In this article, a new hybrid method based on the combination of the genetic algorithm (GA) and artificial neural network (ANN) is developed to optimize the design of three-dimensional (3-D) radiant furnaces. A 3-D irregular shape design body (DB) heated inside a 3-D radiant furnace is considered as a case study. The uniform thermal conditions on the DB surfaces are obtained by minimizing an objective function. An ANN is developed to predict the objective function value which is trained through the data produced by applying the Monte Carlo method. The trained ANN is used in conjunction with the GA to find the optimal design variables. The results show that the computational time using the GA-ANN approach is significantly less than that of the conventional method. It is concluded that the integration of the ANN with GA is an efficient technique for optimization of the radiant furnaces.

Performance of Radiant Heating Systems of Low-Energy Buildings

Science.gov (United States)

Sarbu, Ioan; Mirza, Matei; Crasmareanu, Emanuel

2017-10-01

After the introduction of plastic piping, the application of water-based radiant heating with pipes embedded in room surfaces (i.e., floors, walls, and ceilings), has significantly increased worldwide. Additionally, interest and growth in radiant heating and cooling systems have increased in recent years because they have been demonstrated to be energy efficient in comparison to all-air distribution systems. This paper briefly describes the heat distribution systems in buildings, focusing on the radiant panels (floor, wall, ceiling, and floor-ceiling). Main objective of this study is the performance investigation of different types of low-temperature heating systems with different methods. Additionally, a comparative analysis of the energy, environmental, and economic performances of floor, wall, ceiling, and floor-ceiling heating using numerical simulation with Transient Systems Simulation (TRNSYS) software is performed. This study showed that the floor-ceiling heating system has the best performance in terms of the lowest energy consumption, operation cost, CO2 emission, and the nominal boiler power. The comparison of the room operative air temperatures and the set-point operative air temperature indicates also that all radiant panel systems provide satisfactory results without significant deviations.

Performance analysis on solar-water compound source heat pump for radiant floor heating system

Institute of Scientific and Technical Information of China (English)

曲世林; 马飞; 仇安兵

2009-01-01

A solar-water compound source heat pump for radiant floor heating (SWHP-RFH) experimental system was introduced and analyzed. The SWHP-RFH system mainly consists of 11.44 m2 vacuum tube solar collector,1 000 L water tank assisted 3 kW electrical heater,a water source heat pump,the radiant floor heating system with cross-linked polyethylene (PE-X) of diameter 20 mm,temperature controller and solar testing system. The SWHP-RFH system was tested from December to February during the heating season in Beijing,China under different operation situations. The test parameters include the outdoor air temperature,solar radiation intensity,indoor air temperature,radiation floor average surface temperature,average surface temperature of the building envelope,the inlet and outlet temperatures of solar collector,the temperature of water tank,the heat medium temperatures of heat pump condenser side and evaporator side,and the power consumption includes the water source heat pump system,the solar source heat pump system,the auxiliary heater and the radiant floor heating systems etc. The experimental results were used to calculate the collector efficiency,heat pump dynamic coefficient of performance (COP),total energy consumption and seasonal heating performance during the heating season. The results indicate that the performance of the compound source heat pump system is better than that of the air source heat pump system. Furthermore,some methods are suggested to improve the thermal performance of each component and the whole SWHP-RFH system.

Exergy metrication of radiant panel heating and cooling with heat pumps

International Nuclear Information System (INIS)

Kilkis, Birol

2012-01-01

Highlights: ► Rational Exergy Management Model analytically relates heat pumps and radiant panels. ► Heat pumps driven by wind energy perform better with radiantpanels. ► Better CO 2 mitigation is possible with wind turbine, heat pump, radiant panel combination. ► Energy savings and thermo-mechanical performance are directly linked to CO 2 emissions. - Abstract: Radiant panels are known to be energy efficient sensible heating and cooling systems and a suitable fit for low-exergy buildings. This paper points out the little known fact that this may not necessarily be true unless their low-exergy demand is matched with low-exergy waste and alternative energy resources. In order to further investigate and metricate this condition and shed more light on this issue for different types of energy resources and energy conversion systems coupled to radiant panels, a new engineering metric was developed. Using this metric, which is based on the Rational Exergy Management Model, true potential and benefits of radiant panels coupled to ground-source heat pumps were analyzed. Results provide a new perspective in identifying the actual benefits of heat pump technology in curbing CO 2 emissions and also refer to IEA Annex 49 findings for low-exergy buildings. Case studies regarding different scenarios are compared with a base case, which comprises a radiant panel system connected to a natural gas-fired condensing boiler in heating and a grid power-driven chiller in cooling. Results show that there is a substantial CO 2 emission reduction potential if radiant panels are optimally operated with ground-source heat pumps driven by renewable energy sources, or optimally matched with combined heat and power systems, preferably running on alternative fuels.

Entropy Generation in Thermal Radiative Loading of Structures with Distinct Heaters

Directory of Open Access Journals (Sweden)

Mohammad Yaghoub Abdollahzadeh Jamalabadi

2017-09-01

Full Text Available Thermal loading by radiant heaters is used in building heating and hot structure design applications. In this research, characteristics of the thermal radiative heating of an enclosure by a distinct heater are investigated from the second law of thermodynamics point of view. The governing equations of conservation of mass, momentum, and energy (fluid and solid are solved by the finite volume method and the semi-implicit method for pressure linked equations (SIMPLE algorithm. Radiant heaters are modeled by constant heat flux elements, and the lower wall is held at a constant temperature while the other boundaries are adiabatic. The thermal conductivity and viscosity of the fluid are temperature-dependent, which leads to complex partial differential equations with nonlinear coefficients. The parameter study is done based on the amount of thermal load (presented by heating number as well as geometrical configuration parameters, such as the aspect ratio of the enclosure and the radiant heater number. The results present the effect of thermal and geometrical parameters on entropy generation and the distribution field. Furthermore, the effect of thermal radiative heating on both of the components of entropy generation (viscous dissipation and heat dissipation is investigated.

Radiant heat transfer during the natural evaporation from free surfaces exposed to solar radiation; Transferencia de calor radiante durante a evaporacao natural em superficies livres expostas a radiacao solar

Energy Technology Data Exchange (ETDEWEB)

Teixeira, C O.M. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia; Hackenberg, C M [Universidade Federal do Rio de Janeiro, RJ (Brazil). Escola de Quimica

1985-12-31

In this work a conductive-convective-radiant model which includes phase change behavior, is developed in order to determine the rate of evaporation from free surface exposed to solar radiation and consequently the most important parameters, and their effects, on the design of salt solutions concentrating natural evaporation reservoirs may be analysed. The numerical solutions of the resulting of system of equations are shown to represent very well the experimental results measured on evaporation chambers specially built for daily operations. The thermal effect of spectrally selective surfaces as coating agents for the reservoir is also analysed. (author). 11 refs., 8 figs

The effects of mixing air distribution and heat load arrangement on the performance of ceiling radiant panels under cooling mode of operation

DEFF Research Database (Denmark)

Mustakallio, Panu; Kosonen, Risto; Melikov, Arsen Krikor

2016-01-01

arrangement and air distribution generated in a room by linear slot diffuser, radial multi-nozzle diffuser and radial swirl induction unit on the cooling power of radiant panels was compared. The impact on the thermal environment was also studied. Measurements were carried out without and with supply air...

Exit from contract

Directory of Open Access Journals (Sweden)

Oren Bar-Gill

2016-01-01

Full Text Available Objective to study the procedure of exiting the contract its costs and benefits. Methods statistical method comparative analysis. Results free exit from contract is one of the most powerful tools for the consumer rights protection. The procedure frees consumers from bad deals and keeps businesses honest. Yet consumers often choose transactions with lockin provisions trading off exit rights for other perks. This article examines the costs and benefits of free exit as compared to the lockin alternative. According to the authors the present regulation of exit penalties in the USA is poorly tailored to address concerns about lockin particularly in light of increasingly ubiquitous marketbased solutions. The article also calls regulatory attention to loyalty rewards which are shown to be as powerful as exit penalties and equally detrimental. Scientific novelty the article reveals a paradoxical state of the law exit regulations in the USA are used most where they are needed least. Termination penalties present an obvishyous target for regulatory intervention while loyalty programs seem benign not warranting any regulatory attention. Practical significance the article is of interest for the Russian juridical science and lawmaking authorities as in Russia the issue of exiting the contract is as topical as in the USA and requires solution which would impair neither the rights of consumers nor the rights of the sellers ofnbspproducts and services. nbsp

Exit-strategies

DEFF Research Database (Denmark)

Mørck, Line Lerche; Palm, Anne-Mette; Sys Møller-Andersen, Camilla

different empirical sources. To develop and extend an "exit-prototype" about conditions of importance for moving beyond a gang/criminal position, we have analyzed documents (from newspapers and books), involved ex-gang members, social workers and experts as co-researchers in interviews, "gang......This paper is about exit-strategies, constructing a theoretical and empirical informed analysis of current societal conditions that influence motor cycle gangs such as Hells Angels or Bandidos and other ‘wild' youth' possibilities and limitations for moving beyond criminal activities. We especially...... focus on the involved communities in the current Danish gang-conflict, which escalated with deadly killings in 2008, and thereby became a so called "gang-war". We will start out presenting different practice notions of exit, and we will extend and discuss understandings of "exit-strategies" by analyzing...

High-temperature process heat reactor with solid coolant and radiant heat exchange

International Nuclear Information System (INIS)

Alekseev, A.M.; Bulkin, Yu.M.; Vasil'ev, S.I.

1984-01-01

The high temperature graphite reactor with the solid coolant in which heat transfer is realized by radiant heat exchange is described. Neutron-physical and thermal-technological features of the reactor are considered. The reactor vessel is made of sheet carbon steel in the form of a sealed rectangular annular box. The moderator is a set of graphite blocks mounted as rows of arched laying Between the moderator rows the solid coolant annular layings made of graphite blocks with high temperature nuclear fuel in the form of coated microparticles are placed. The coolant layings are mounted onto ring movable platforms, the continuous rotation of which is realizod by special electric drives. Each part of the graphite coolant laying consecutively passes through the reactor core neutron cut-off zones and technological zone. In the core the graphite is heated up to the temperature of 1350 deg C sufficient for effective radiant heat transfer. In the neutron cut-off zone the chain reaction and further graphite heating are stopped. In the technological zone the graphite transfers the accumulated heat to the walls of technological channels in which the working medium moves. The described reactor is supposed to be used in nuclear-chemical complex for ammonia production by the method of methane steam catalytic conversion

Subjective evaluation of different ventilation concepts combined with radiant heating and cooling

DEFF Research Database (Denmark)

Krajcik, Michal; Tomasi, Roberta; Simone, Angela

2012-01-01

Sixteen subjects evaluated the indoor environment in four experiments with different combinations of ventilation and radiant heating/cooling systems. Two test setups simulated a room in a low energy building with a single occupant during winter. The room was equipped either by a ventilation system...... supplying warm air space heating or by a combination of radiant floor heating and mixing ventilation system. Next two test setups simulated an office room with two occupants during summer, ventilated and cooled by a single displacement ventilation system or by a radiant floor cooling combined...

Ignition of Cellulosic Paper at Low Radiant Fluxes

Science.gov (United States)

White, K. Alan

1996-01-01

The ignition of cellulosic paper by low level thermal radiation is investigated. Past work on radiative ignition of paper is briefly reviewed. No experimental study has been reported for radiative ignition of paper at irradiances below 10 Watts/sq.cm. An experimental study of radiative ignition of paper at these low irradiances is reported. Experimental parameters investigated and discussed include radiant power levels incident on the sample, the method of applying the radiation (focussed vs. diffuse Gaussian source), the presence and relative position of a separate pilot ignition source, and the effects of natural convection (buoyancy) on the ignition process in a normal gravity environment. It is observed that the incident radiative flux (in W/sq.cm) has the greatest influence on ignition time. For a given flux level, a focussed Gaussian source is found to be advantageous to a more diffuse, lower amplitude, thermal source. The precise positioning of a pilot igniter relative to gravity and to the fuel sample affects the ignition process, but the precise effects are not fully understood. Ignition was more readily achieved and sustained with a horizontal fuel sample, indicating the buoyancy plays a role in the ignition process of cellulosic paper. Smoldering combustion of doped paper samples was briefly investigated, and results are discussed.

Numerical Simulation of the Application of Solar Radiant Systems, Internal Airflow and Occupants’ Presence in the Improvement of Comfort in Winter Conditions

Directory of Open Access Journals (Sweden)

Eusébio Z. E. Conceição

2016-09-01

Full Text Available In this work, the use of numerical simulation in the application of solar radiant systems, internal airflow and occupants’ presence in the improvement of comfort in winter conditions is made. The thermal comfort, the local thermal discomfort and the air quality in an occupied chamber space are evaluated. In the experimental measurements, a wood chamber, a desk, two seats, two seated hygro-thermal manikins, a warm radiant floor, a solar radiation simulator and a water solar collector are used. The air velocity and the air temperature fluctuation are experimentally evaluated around 15 human body sections. The chamber surface temperature is experimentally measured. In the numerical simulation, a coupling human thermal comfort (HTC integral model, a computational fluids dynamics (CFD differential model and a building thermal response (BTR integral model are applied. The human thermal comfort level is evaluated by the HTC numerical model. The airflow inside the virtual chamber, using the k-epsilon and RNG turbulence models, is evaluated by the CFD numerical model. The chamber surface and the collector temperatures are evaluated by the BTR numerical model. In the human thermal comfort level, in non-uniform environments, the predicted mean vote (PMV and the predicted percentage of dissatisfied (PPD people are numerically evaluated; in the local thermal discomfort level the draught risk (DR is experimentally and numerically analyzed; and in the air quality, the carbon dioxide CO2 concentration is numerically calculated. In the validation tests, the experimental and numerical values of the chamber surface temperature, the air temperature, the air velocity, the air turbulence intensity and the DR are presented.

Exit Prostitution

DEFF Research Database (Denmark)

Henriksen, Theresa Dyrvig; Aslaug Kjær, Agnete; Christensen, Gunvor

2015-01-01

Dette midtvejsnotat omhandler projektet ”Exit prostitution”. Exit-projektet blev påbegyndt i april 2012 og løber til udgangen af 2015 og befinder sig i øjeblikket midtvejs i projektets afprøvningsfase. I projektet anvendes metoden Critical Time Intervention (CTI), der er en evidensbaseret...... til det. Exit-projektet er dermed en central socialpolitisk indsats overfor borgere i prostitution i det danske samfund. I dette notat belyser vi midtvejsresultater for, hvordan udviklingen er for de borgere, der er nået halvt igennem et CTI-forløb. I den afsluttende evaluering af projektet i 2015 vil...

Error analysis of thermocouple measurements in the Radiant Heat Facility

International Nuclear Information System (INIS)

Nakos, J.T.; Strait, B.G.

1980-12-01

The measurement most frequently made in the Radiant Heat Facility is temperature, and the transducer which is used almost exclusively is the thermocouple. Other methods, such as resistance thermometers and thermistors, are used but very rarely. Since a majority of the information gathered at Radiant Heat is from thermocouples, a reasonable measure of the quality of the measurements made at the facility is the accuracy of the thermocouple temperature data

Advanced radiant combustion system. Final report, September 1989--September 1996

Energy Technology Data Exchange (ETDEWEB)

Sullivan, J.D.; Carswell, M.G.; Long, F.S.

1996-09-01

Results of the Advanced Radiant Combustion System (ARCS) project are presented in this report. This work was performed by Alzeta Corporation as prime contractor under a contract to the U.S. Department of Energy Office of Industrial Technologies as part of a larger DOE program entitled Research Program for Advanced Combustion Systems. The goals of the Alzeta ARCS project were to (a) Improve the high temperature performance characteristics of porous surface ceramic fiber burners, (b) Develop an Advanced Radiant Combustion System (ARCS) that combines combustion controls with an advanced radiant burner, and (c) Demonstrate the advanced burner and controls in an industrial application. Prior to the start of this project, Alzeta had developed and commercialized a porous surface radiant burner, the Pyrocore{trademark} burner. The product had been commercially available for approximately 5 years and had achieved commercial success in a number of applications ranging from small burners for commercial cooking equipment to large burners for low temperature industrial fluid heating applications. The burner was not recommended for use in applications with process temperatures above 1000{degrees}F, which prevented the burner from being used in intermediate to high temperature processes in the chemical and petroleum refining industries. The interest in increasing the maximum use temperature of the burner was motivated in part by a desire to expand the number of applications that could use the Pyrocore product, but also because many of the fluid sensitive heating applications of interest would benefit from the distributed flux characteristic of porous surface burners. Background information on porous surface radiant burners, and a discussion of advantages that would be provided by an improved product, are presented in Section 2.

A Simulation Study on the Performance of Radiant Ceilings Combined with Free-Hanging Horizontal Sound Absorbers

DEFF Research Database (Denmark)

Kazanci, Ongun Berk; Domínguez, L. Marcos; Rage, Niels

2018-01-01

using TABS, most building simulation models assume an uncovered ceiling; however, this might not be the case in practice, due to the use of free-hanging horizontal (or vertical) sound absorbers for the control of room acoustic conditions. The use of sound absorbers will decrease the performance...... of radiant ceiling cooling systems. Therefore, the quantification of the effects during the design phase is important for predicting the resulting thermal indoor environment and for system dimensioning. In this study, a two-person office room equipped with TABS was simulated using a commercially available...... simulation software with a recently developed plug-in that allows simulating the effects of horizontal sound absorbers on the performance of TABS and on the thermal indoor environment. The change in thermal indoor environment and in performance of TABS were quantified, and the simulation results were...

Human response to local convective and radiant cooling in a warm environment

DEFF Research Database (Denmark)

Melikov, Arsen Krikor; Krejcirikova, Barbora; Kaczmarczyk, Jan

2013-01-01

The response of 24 human subjects to local convective cooling, radiant cooling, and combined radiant and convective cooling was studied at 28°C and 50% relative humidity. The local cooling devices used were (1) a tabletop cooling fan, (2) personalized ventilation providing a stream of clean air, (3...

Critical heat flux and exit film flow rate in a flow boiling system

International Nuclear Information System (INIS)

Ueda, Tatsuhiro; Isayama, Yasushi

1981-01-01

The critical heat flux in a flowing boiling system is an important problem in the evaporating tubes with high thermal load such as nuclear reactors and boilers, and gives the practical design limit. When the heat flux in uniformly heated evaporating tubes is gradually raised, the tube exit quality increases, and soon, the critical heat flux condition arises, and the wall temperature near tube exit rises rapidly. In the region of low exit quality, the critical heat flux condition is caused by the transition from nucleating boiling, and in the region of high exit quality, it is caused by dry-out. But the demarcation of both regions is not clear. In this study, for the purpose of obtaining the knowledge concerning the critical heat flux condition in a flowing boiling system, the relation between the critical heat flux and exit liquid film flow rate was examined. For the experiment, a uniformly heated vertical tube supplying R 113 liquid was used, and the measurement in the range of higher heating flux and mass velocity than the experiment by Ueda and Kin was carried out. The experimental setup and experimental method, the critical heat flux and exit quality, the liquid film flow rate at heating zone exit, and the relation between the critical heat flux and the liquid film flow rate at exit are described. (Kako, I.)

Present and projected future mean radiant temperature for three European cities

Science.gov (United States)

Thorsson, Sofia; Rayner, David; Lindberg, Fredrik; Monteiro, Ana; Katzschner, Lutz; Lau, Kevin Ka-Lun; Campe, Sabrina; Katzschner, Antje; Konarska, Janina; Onomura, Shiho; Velho, Sara; Holmer, Björn

2017-09-01

Present-day and projected future changes in mean radiant temperature, T mrt in one northern, one mid-, and one southern European city (represented by Gothenburg, Frankfurt, and Porto), are presented, and the concept of hot spots is adopted. Air temperature, T a , increased in all cities by 2100, but changes in solar radiation due to changes in cloudiness counterbalanced or exacerbated the effects on T mrt. The number of days with high T mrt in Gothenburg was relatively unchanged at the end of the century (+1 day), whereas it more than doubled in Frankfurt and tripled in Porto. The use of street trees to reduce daytime radiant heat load was analyzed using hot spots to identify where trees could be most beneficial. Hot spots, although varying in intensity and frequency, were generally confined to near sunlit southeast-southwest facing walls, in northeast corner of courtyards, and in open spaces in all three cities. By adding trees in these spaces, the radiant heat load can be reduced, especially in spaces with no or few trees. A set of design principles for reducing the radiant heat load is outlined based on these findings and existing literature.

Exit prostitution

DEFF Research Database (Denmark)

Mehlsen, Line; Aslaug Kjær, Agnete; Amilon, Anna

2016-01-01

Dette statusnotat for projektet ”Exit Prostitution” belyser de foreløbige resultater og tendenser for projektet. Exit Prostitution løb oprindeligt fra april 2012 til udgangen af 2015, men med en nylig forlængelse løber projektet til udgangen af 2016. Projektet befinder sig således i slutningen af...... afprøvet med succes i forhold til hjemløshed både nationalt og internationalt. Målet med anvendelsen af metoden i forhold til målgruppen for Exit Prostitution er, at borgere med prostitutionserfaring, som ønsker at ophøre med salg af seksuelle ydelser eller ønsker at opleve en forbedring af deres...

Evaluation of Various Retrofitting Concepts of Building Envelope for Offices Equipped with Large Radiant Ceiling Panels by Dynamic Simulations

Directory of Open Access Journals (Sweden)

Sabina Jordan

2015-09-01

Full Text Available In order to achieve significant savings in energy and an improved level of thermal comfort in retrofitted existing buildings, specific retrofitting concepts that combine new technologies and design need to be developed and implemented. Large radiant surfaces systems are now among the most promising future technologies to be used both in retrofitted and in new low-energy buildings. These kinds of systems have been the topic of several studies dealing with thermal comfort and energy utilization, but some specific issues concerning their possible use in various concepts for retrofitting are still poorly understood. In the present paper, some results of dynamic simulations, with the transient system simulation tool (TRNSYS model, of the retrofitted offices equipped with radiant ceiling panels are presented and thoroughly analysed. Based on a precise comparison of the results of these simulations with actual measurements in the offices, certain input data for the model were added, so that the model was consequently validated. The model was then applied to the evaluation of various concepts of building envelopes for office retrofitting. By means of dynamic simulations of indoor environment it was possible to determine the benefits and limitations of individual retrofitting concepts. Some specific parameters, which are relevant to these concepts, were also identified.

Fixed, low radiant exposure vs. incremental radiant exposure approach for diode laser hair reduction: a randomized, split axilla, comparative single-blinded trial.

Science.gov (United States)

Pavlović, M D; Adamič, M; Nenadić, D

2015-12-01

Diode lasers are the most commonly used treatment modalities for unwanted hair reduction. Only a few controlled clinical trials but not a single randomized controlled trial (RCT) compared the impact of various laser parameters, especially radiant exposure, onto efficacy, tolerability and safety of laser hair reduction. To compare the safety, tolerability and mid-term efficacy of fixed, low and incremental radiant exposures of diode lasers (800 nm) for axillary hair removal, we conducted an intrapatient, left-to-right, patient- and assessor-blinded and controlled trial. Diode laser (800 nm) treatments were evaluated in 39 study participants (skin type II-III) with unwanted axillary hairs. Randomization and allocation to split axilla treatments were carried out by a web-based randomization tool. Six treatments were performed at 4- to 6-week intervals with study subjects blinded to the type of treatment. Final assessment of hair reduction was conducted 6 months after the last treatment by means of blinded 4-point clinical scale using photographs. The primary endpoint was reduction in hair growth, and secondary endpoints were patient-rated tolerability and satisfaction with the treatment, treatment-related pain and adverse effects. Excellent reduction in axillary hairs (≥ 76%) at 6-month follow-up visit after receiving fixed, low and incremental radiant exposure diode laser treatments was obtained in 59% and 67% of study participants respectively (Z value: 1.342, P = 0.180). Patients reported lower visual analogue scale (VAS) pain score on the fixed (4.26) than on the incremental radiant exposure side (5.64) (P diode laser treatments were less painful and better tolerated. © 2015 European Academy of Dermatology and Venereology.

Assessing the accuracy of globe thermometer method in predicting outdoor mean radiant temperature under Malaysia tropical microclimate

Science.gov (United States)

Khrit, N. G.; Alghoul, M. A.; Sopian, K.; Lahimer, A. A.; Elayeb, O. K.

2017-11-01

Assessing outdoor human thermal comfort and urban climate quality require experimental investigation of microclimatic conditions and their variations in open urban spaces. For this, it is essential to provide quantitative information on air temperature, humidity, wind velocity and mean radiant temperature. These parameters can be quantified directly except mean radiant temperature (Tmrt). The most accurate method to quantify Tmrt is integral radiation measurements (3-D shortwave and long-wave) which require using expensive radiometer instruments. To overcome this limitation the well-known globe thermometer method was suggested to calculate Tmrt. The aim of this study was to assess the possibility of using indoor globe thermometer method in predicting outdoor mean radiant temperature under Malaysia tropical microclimate. Globe thermometer method using small and large sizes of black-painted copper globes (50mm, 150mm) were used to estimate Tmrt and compare it with the reference Tmrt estimated by integral radiation method. The results revealed that the globe thermometer method considerably overestimated Tmrt during the middle of the day and slightly underestimated it in the morning and late evening. The difference between the two methods was obvious when the amount of incoming solar radiation was high. The results also showed that the effect of globe size on the estimated Tmrt is mostly small. Though, the estimated Tmrt by the small globe showed a relatively large amount of scattering caused by rapid changes in radiation and wind speed.

Three-dimensional simulation of super-radiant Smith-Purcell radiation

International Nuclear Information System (INIS)

Li, D.; Imasaki, K.; Yang, Z.; Park, Gun-Sik

2006-01-01

A simulation of coherent and super-radiant Smith-Purcell radiation is performed in the gigahertz regime using a three-dimensional particle-in-cell code. The simulation model supposes a rectangular grating to be driven by a single electron bunch and a train of periodic bunches, respectively. The true Smith-Purcell radiation is distinguished from the evanescent wave, which has an angle independent frequency lower than the minimum allowed Smith-Purcell frequency. We also find that the super-radiant radiations excited by periodic bunches are emitted at higher harmonics of the bunching frequency and at the corresponding Smith-Purcell angles

Radiant heat increases piglets’ use of the heated creep area on the critical days after birth

DEFF Research Database (Denmark)

Larsen, Mona Lilian Vestbjerg; Thodberg, Karen; Pedersen, Lene Juul

2017-01-01

The aim of the present study was to investigate how piglets’ use of a creep area is affected by using radiant heat compared to an incandescent light bulb. It was hypothesised that radiant heat would increase the use of the creep area. Twenty litters were randomly assigned to one of two heat sources...... in the creep area: (1) an incandescent light bulb (STANDARD, n=10) or (2) a radiant heat source (RADIANT, n=10) with five of each type of heat source in each of two batches. Observations on piglets’ position in the pen were made by scan sampling every ten minutes in a 4-hour period from 1100 to 1500 h on day 1......–7, 14 and 21 post partum. A higher percentage of piglets in the creep area was seen for RADIANT litters compared to STANDARD litters on day 2 (P=0.002) and day 3 (P=0.005), and percentage of piglets in the creep area increased for RADIANT litters from day 1 to 2 (P

Surface radiant flux densities inferred from LAC and GAC AVHRR data

Science.gov (United States)

Berger, F.; Klaes, D.

To infer surface radiant flux densities from current (NOAA-AVHRR, ERS-1/2 ATSR) and future meteorological (Envisat AATSR, MSG, METOP) satellite data, the complex, modular analysis scheme SESAT (Strahlungs- und Energieflüsse aus Satellitendaten) could be developed (Berger, 2001). This scheme allows the determination of cloud types, optical and microphysical cloud properties as well as surface and TOA radiant flux densities. After testing of SESAT in Central Europe and the Baltic Sea catchment (more than 400scenes U including a detailed validation with various surface measurements) it could be applied to a large number of NOAA-16 AVHRR overpasses covering the globe.For the analysis, two different spatial resolutions U local area coverage (LAC) andwere considered. Therefore, all inferred results, like global area coverage (GAC) U cloud cover, cloud properties and radiant properties, could be intercompared. Specific emphasis could be made to the surface radiant flux densities (all radiative balance compoments), where results for different regions, like Southern America, Southern Africa, Northern America, Europe, and Indonesia, will be presented. Applying SESAT, energy flux densities, like latent and sensible heat flux densities could also be determined additionally. A statistical analysis of all results including a detailed discussion for the two spatial resolutions will close this study.

Thermal performance of various multilayer insulation systems below 80K

International Nuclear Information System (INIS)

Boroski, W.N.; Nicol, T.H.; Schoo, C.J.

1992-04-01

The SSC collider dipole cryostat consists of a vacuum shell operating at room temperature, two thermal shields operating near 80K and 20K respectively, and the superconducting magnet assembly operating near 4K. The cryostat design incorporates multilayer insulation (MLI) blankets to limit radiant heat transfer into the 80K and 20K thermal shields. Also, an MLI blanket is used to impede heat transfer through residual gas conduction into the 4K superconducting magnet assembly. A measurement facility at Fermilab has been used to experimentally optimize the thermal insulation system for the dipole cryostat. Previous thermal measurements have been used to define the 80K MLI system configuration and verify system performance. With the 80K MLI system defined, the current effort has focused on experimentally defining the optimum insulation scheme for the 20K thermal shield. The SSC design specification requires that radiant heat transfer be limited to 0.093 W/m 2 at an insulating vacuum of 10 -6 torr

Radiative heat exchange of a meteor body in the approximation of radiant heat conduction

International Nuclear Information System (INIS)

Pilyugin, N.N.; Chernova, T.A.

1986-01-01

The problem of the thermal and dynamic destruction of large meteor bodies moving in planetary atmospheres is fundamental for the clarification of optical observations and anomalous phenomena in the atmosphere, the determination of the physicochemical properties of meteoroids, and the explanation of the fall of remnants of large meteorites. Therefore, it is important to calculate the coefficient of radiant heat exchange (which is the determining factor under these conditions) for large meteor bodies as they move with hypersonic velocities in an atmosphere. The solution of this problem enables one to find the ablation of a meteorite during its aerodynamic heating and to determine the initial conditions for the solution of problems of the breakup of large bodies and their subsequent motion and ablation. Hypersonic flow of an inviscid gas stream over an axisymmetric blunt body is analyzed with allowance for radiative transfer in a thick-thin approximation. The gas-dynamic problem of the flow of an optically thick gas over a large body is solved by the method of asymptotic joined expansions, using a hypersonic approximation and local self-similarity. An equation is obtained for the coefficient of radiant heat exchange and the peculiarities of such heat exchange for meteor bodies of large size are noted

Reducing heat loss from the energy absorber of a solar collector

Science.gov (United States)

Chao, Bei Tse; Rabl, Ari

1976-01-01

A device is provided for reducing convective heat loss in a cylindrical radiant energy collector. It includes a curved reflective wall in the shape of the arc of a circle positioned on the opposite side of the exit aperture from the reflective side walls of the collector. Radiant energy exiting the exit aperture is directed by the curved wall onto an energy absorber such that the portion of the absorber upon which the energy is directed faces downward to reduce convective heat loss from the absorber.

Radiant absorption characteristics of corrugated curved tubes

Directory of Open Access Journals (Sweden)

Đorđević Milan Lj.

2017-01-01

Full Text Available The utilization of modern paraboloidal concentrators for conversion of solar radiation into heat energy requires the development and implementation of compact and efficient heat absorbers. Accurate estimation of geometry influence on absorption characteristics of receiver tubes is an important step in this process. This paper deals with absorption characteristics of heat absorber made of spirally coiled tubes with transverse circular corrugations. Detailed 3-D surface-to-surface Hemicube method was applied to compare radiation performances of corrugated and smooth curved tubes. The numerical results were obtained by varying the tube curvature ratio and incident radiant heat flux intensity. The details of absorption efficiency of corrugated tubes and the effect of curvature on absorption properties for both corrugated and smooth tubes were presented. The results may have significance to further analysis of highly efficient heat absorbers exposed to concentrated radiant heating. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 42006

Smart Control of Air Climatization System in Function on the Values of Mean Local Radiant Temperature

Directory of Open Access Journals (Sweden)

Giuseppe Cannistraro

2015-08-01

Full Text Available The hygrothermal comfort indoor conditions are defined as: those environmental conditions in which an individual exposed, expresses a state of satisfaction. These conditions cannot always be achieved anywhere in an optimal way and economically; in some cases they can be obtained only in work environments specific areas. This could be explained because of air conditioning systems designing is generally performed both on the basis of the fundamental parameters’ average values, such as temperature, velocity and relative humidity (Ta, va e φa and derived parameters such as operating temperature and mean radiant one (Top eTmr. However, in some specific cases - large open-spaces or in case of radiating surfaces - the descriptors defining indoor comfort conditions, based on average values, do not provide the optimum values required during the air conditioning systems design phase. This is largely due to the variability of real environmental parameters values compared to the average ones taken as input in the calculation. The results obtained in previous scientific papers on the thermal comfort have been the driving element of this work. It offers a simple, original and clever way of thinking about the new domotic systems for air conditioning, based on the “local mean radiant temperature.” This is a very important parameter when one wants to analyze comfort in environments characterized by the presence of radiating surfaces, as will be seen hereinafter. In order to take into account the effects of radiative exchanges in the open-space workplace, where any occupant may find themselves in different temperature and humidity conditions, this paper proposes an action on the domotic climate control, with ducts and vents air distribution placed in different zones. Comparisons were performed between the parameters values representing the punctual thermal comfort, with the Predicted Mean Vote PMV, in an environment marked by radiating surfaces (i

Radiant Barriers Save Energy in Buildings

Science.gov (United States)

2014-01-01

Langley Research Center needed to coat the Echo 1 satellite with a fine mist of vaporized metal, and collaborated with industry to create "radiant barrier technology." In 2010, Ryan Garrett learned about a new version of the technology resistant to oxidation and founded RadiaSource in Ogden, Utah, to provide the NASA-derived technology for applications in homes, warehouses, gymnasiums, and agricultural settings.

Experimental evaluation of heat transfer coefficients between radiant ceiling and room

DEFF Research Database (Denmark)

Causone, Francesco; Corgnati, Stefano P.; Filippi, Marco

2009-01-01

The heat transfer coefficients between radiant surfaces and room are influenced by several parameters: surfaces temperature distributions, internal gains, air movements. The aim of this paper is to evaluate the heat transfer coefficients between radiant ceiling and room in typical conditions...... of occupancy of an office or residential building. Internal gains were therefore simulated using heated cylinders and heat losses using cooled surfaces. Evaluations were developed by means of experimental tests in an environmental chamber. Heat transfer coefficient may be expressed separately for radiation...

Radiometric measurements of wall temperatures in the 800 K to 1150 K range for a quartz radiant heating tube

International Nuclear Information System (INIS)

Blevins, L.G.; Sivathanu, Y.R.; Gore, J.P.; Shahien, M.A.

1995-01-01

Many industrial applications require heat transfer to a load in an inert environment, which can be achieved by using gas-fired radiant tubes. A radiant tube consists of a flame confined in a cylindrical metal or ceramic chamber. The flame heats the tube wall, which in turn radiates to the load. One important characteristic of radiant heating tubes is wall temperature uniformity. Numerical models of radiant tubes have been used to predict wall temperatures, but there is a lack of experimental data for validation. Recently, Namazian et al., Singh and Gorski, and Peters et al. have measured wall temperature profiles of radiant tubes using thermocouples. 13 refs., 3 figs

Pollutant emissions reduction and performance optimization of an industrial radiant tube burner

Energy Technology Data Exchange (ETDEWEB)

Scribano, Gianfranco; Solero, Giulio; Coghe, Aldo [Dipartimento di Energetica, Politecnico di Milano, via La Masa, 34, 20156 Milano (Italy)

2006-07-15

This paper presents the results of an experimental investigation performed upon a single-ended self-recuperative radiant tube burner fuelled by natural gas in the non-premixed mode, which is used in the steel industry for surface treatment. The main goal of the research activity was a systematic investigation of the burner aimed to find the best operating conditions in terms of optimum equivalence ratio, thermal power and lower pollutant emissions. The analysis, which focused on the main parameters influencing the thermal efficiency and pollutant emissions at the exhaust (NO{sub x} and CO), has been carried out for different operating conditions of the burner: input thermal powers from 12.8 up to 18kW and equivalence ratio from 0.5 (very lean flame) to 0.95 (quasi-stoichiometric condition). To significantly reduce pollutant emissions ensuring at the same time the thermal requirements of the heating process, it has been developed a new burner configuration, in which a fraction of the exhaust gases recirculates in the main combustion region through a variable gap between the burner efflux and the inner flame tube. This internal recirculation mechanism (exhaust gases recirculation, EGR) has been favoured through the addition of a pre-combustion chamber terminated by a converging nozzle acting as a mixing/ejector to promote exhaust gas entrainment into the flame tube. The most important result of this solution was a decrease of NO{sub x} emissions at the exhaust of the order of 50% with respect to the original burner geometry, for a wide range of thermal power and equivalence ratio. (author)

29 CFR 1917.122 - Employee exits.

Science.gov (United States)

2010-07-01

... 29 Labor 7 2010-07-01 2010-07-01 false Employee exits. 1917.122 Section 1917.122 Labor Regulations...) MARINE TERMINALS Terminal Facilities § 1917.122 Employee exits. (a) Employee exits shall be clearly marked. (b) If an employee exit is not visible from employees' work stations, directional signs...

16 CFR Figure 3 to Subpart A of... - Flooring Radiant Tester Schematic Side Elevation

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Flooring Radiant Tester Schematic Side Elevation 3 Figure 3 to Subpart A of Part 1209 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION.... 1209, Subpt. A, Fig. 3 Figure 3 to Subpart A of Part 1209—Flooring Radiant Tester Schematic Side...

Radiant energy collection and conversion apparatus and method

Science.gov (United States)

Hunt, A.J.

The apparatus for collecting radiant energy and converting to alternate energy forms includes a housing having an interior space and a radiation transparent window allowing solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past the window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

Natural convection heat transfer coefficient for newborn baby - Thermal manikin assessed convective heat loses

Science.gov (United States)

Ostrowski, Ziemowit; Rojczyk, Marek

2017-11-01

The energy balance and heat exchange for newborn baby in radiant warmer environment are considered. The present study was performed to assess the body dry heat loss from an infant in radiant warmer, using copper cast anthropomorphic thermal manikin and controlled climate chamber laboratory setup. The total body dry heat losses were measured for varying manikin surface temperatures (nine levels between 32.5 °C and 40.1 °C) and ambient air temperatures (five levels between 23.5 °C and 29.7 °C). Radiant heat losses were estimated based on measured climate chamber wall temperatures. After subtracting radiant part, resulting convective heat loses were compared with computed ones (based on Nu correlations for common geometries). Simplified geometry of newborn baby was represented as: (a) single cylinder and (b) weighted sum of 5 cylinders and sphere. The predicted values are significantly overestimated relative to measured ones by: 28.8% (SD 23.5%) for (a) and 40.9% (SD 25.2%) for (b). This showed that use of adopted general purpose correlations for approximation of convective heat losses of newborn baby can lead to substantial errors. Hence, new Nu number correlating equation is proposed. The mean error introduced by proposed correlation was reduced to 1.4% (SD 11.97%), i.e. no significant overestimation. The thermal manikin appears to provide a precise method for the noninvasive assessment of thermal conditions in neonatal care.

Super-radiant Smith–Purcell radiation from periodic line charges

International Nuclear Information System (INIS)

Li, D.; Hangyo, M.; Tsunawaki, Y.; Yang, Z.; Wei, Y.; Miyamoto, S; Asakawa, M.R.; Imasaki, K.

2012-01-01

Smith–Purcell radiation occurs when an electron passes close to the surface of a metallic grating. The radiation becomes coherent when the length of the electron bunch is smaller than the wavelength of the radiation. A train of periodic bunches can enhance the spectral intensity by changing the angular and spectral distribution of the radiation. This is called super-radiant Smith–Purcell radiation, and has been observed in experiments and particle-in-cell simulations. In this paper, we introduce a new method to study this effect by calculating the reflected waves of an incident evanescent wave from periodic line charges. The reflection coefficients are numerically computed, and the spectral distributions of the super-radiant radiation are demonstrated. These analytical results are in agreement with those obtained through part-in-cell simulations.

Exit Polls and Voter Turnout

DEFF Research Database (Denmark)

Andersen, Asger Lau; Jensen, Thomas

2014-01-01

After the 2009 referendum on a proposed change to the Danish Law of Succession, it was widely claimed that the early publication of exit poll results changed the rate of turnout and eventually the outcome. We investigate this claim and contribute to the wider debate on the implications of exit...... polls by setting up and analyzing a formal model. We find that the introduction of an exit poll influences the incentive to vote both before and after the poll is published, but the signs of the effects are generally ambiguous. The observation that exit polls influence the incentive to vote even before...

Integrated application of combined cooling, heating and power poly-generation PV radiant panel system of zero energy buildings

Science.gov (United States)

Yin, Baoquan

2018-02-01

A new type of combined cooling, heating and power of photovoltaic radiant panel (PV/R) module was proposed, and applied in the zero energy buildings in this paper. The energy system of this building is composed of PV/R module, low temperature difference terminal, energy storage, multi-source heat pump, energy balance control system. Radiant panel is attached on the backside of the PV module for cooling the PV, which is called PV/R module. During the daytime, the PV module was cooled down with the radiant panel, as the temperature coefficient influence, the power efficiency was increased by 8% to 14%, the radiant panel solar heat collecting efficiency was about 45%. Through the nocturnal radiant cooling, the PV/R cooling capacity could be 50 W/m2. For the multifunction energy device, the system shows the versatility during the heating, cooling and power used of building utilization all year round.

A comparison of suit dresses and summer clothes in the terms of thermal comfort.

Science.gov (United States)

Ekici, Can; Atilgan, Ibrahim

2013-12-19

Fanger's PMV equation is the result of the combined quantitative effects of the air temperature, mean radiant temperature, relative air velocity, humidity, activity level and clothing insulation. This paper contains a comparison of suit dresses and summer clothes in terms of thermal comfort, Fanger's PMV equation. Studies were processed in the winter for an office, which locates in Ankara, Turkey. The office was partitioned to fifty square cells. Humidity, relative air velocity, air temperature and mean radiant temperature were measured on the centre points of these cells. Thermal comfort analyses were processed for suit dressing (Icl = 1 clo) and summer clothing (Icl = 0.5 clo). Discomfort/comfort in an environment for different clothing types can be seen in this study. The relationship between indoor thermal comfort distribution and clothing type was discussed. Graphics about thermal comfort were sketched according to cells. Conclusions about the thermal comfort of occupants were given by PMV graphics.

Condensate subcooling near tube exit during horizontal in-tube condensation

International Nuclear Information System (INIS)

Hashizume, K.; Abe, N.; Ozeki, T.

1992-01-01

In-tube condensation is encountered in various applications for heat exchangers, such as domestic air-conditioning equipment, industrial air-cooled condensers, and moisture separator reheaters (MSRs) for nuclear power pants. Numerous research work has been conducted to predict the condensation heat transfer coefficient, and we have now enough information for thermal design of heat exchangers with horizontal in-tube condensation. Most of the research is analytical and/or experimental work in the annular or stratified flow regime, or experimental work on bulk condensation, i.e., from saturated vapor to complete condensation. On the other hand, there exist few data about the heat transfer phenomena in the very lower-quality region near the tube exit. The purpose of this paper is to clarify the condensation heat transfer phenomena near the tube exit experimentally and analytically, and to predict the degree of condensate subcooling

Thermal test options

International Nuclear Information System (INIS)

Koski, J.A.; Keltner, N.R.; Sobolik, K.B.

1993-02-01

Shipping containers for radioactive materials must be qualified to meet a thermal accident environment specified in regulations, such at Title 10, Code of Federal Regulations, Part 71. Aimed primarily at the shipping container design, this report discusses the thermal testing options available for meeting the regulatory requirements, and states the advantages and disadvantages of each approach. The principal options considered are testing with radiant heat, furnaces, and open pool fires. The report also identifies some of the facilities available and current contacts. Finally, the report makes some recommendations on the appropriate use of these different testing methods

Radiant heating of petroleum reservoirs; Aquecimento radiante de reservatorios petroliferos

Energy Technology Data Exchange (ETDEWEB)

Sidrim, Fernando A.C.

1990-12-31

This work presents a proposal of a simplified model for the enhanced oil recovery process through radiant heating of oil reservoirs. The resulting continuity, energy and motion equations were solved analytically for the prediction of the increase in well flow rates. The heat loss to adjacent formations and the necessary for the establishment of the temperature profile,which are transient terms of energy equation, have been neglected. Also, no temperature gradient in the axial direction has been modelled as a cylindrical wave propagating in a loss medium. It is concluded that: the inclusion of a radial conduction term in the energy equation led to higher flow rates than the ones predicted by the literature existing solution; if the absorption coefficient is too large, it is profitable to dry the reservoir around the well bore; the transient terms in the energy equation are significant for extended periods of well production. 47 refs., 18 figs., 4 tabs.

Firm Exit, Technological Progress and Trade

DEFF Research Database (Denmark)

Schröder, Philipp; Sørensen, Allan

The dynamics of export market exit and firm closure have found limited attention in the new heterogeneous-firms trade literature. In fact, several of the predictions on firm survival and exit stemming from this new class of models are at odds with the stylized facts. Empirically, higher productiv......The dynamics of export market exit and firm closure have found limited attention in the new heterogeneous-firms trade literature. In fact, several of the predictions on firm survival and exit stemming from this new class of models are at odds with the stylized facts. Empirically, higher...... productivity firms survive longer, most firm closures are young firms, higher productivity exporters are more likely to continue to export compared to less productive exporters and market exits as well as firm closures are typically preceded by periods of contracting market shares. The present paper shows...... liberalization on export market exit and firm closure....

Automatic drawing and CAD actualization in processing data of radiant sampling in physics prospect

International Nuclear Information System (INIS)

Liu Jinsheng

2010-01-01

In this paper discussed a method of processing radiant sampling data with computer. By this method can get expain the curve of radiant sampling data, and we can combine mineral masses and analyse and calculate them, then record the result on Notebook. There are many merites of this method: easy to learn, simple to use, high efficient. It adapts to all sorts of mines. (authors)

Automatic drawing and cad actualiztion in processing data of radiant sampling in physics prospect

International Nuclear Information System (INIS)

Liu Jinsheng

2010-01-01

In this paper discussed a method of processing radiant sampling data with computer. By this method can get explain the curve of radiant sampling data, and we can combine mineral masses and analyses and calculate them, then record the result on Notebook. There are many merites of this method: easy to learn, simple to use, high efficient. It adapts to all sorts of mines. (authors)

Volcanism on Io: The Galileo NIMS Io Thermal Emission Database (NITED)

Science.gov (United States)

Davies, A. G.; Veeder, G. J.; Matson, D. L.; Johnson, T. V.

2011-12-01

In order to determine the magnitude of thermal emission from Io's volcanoes and variability with time at local, regional and global scales, we have calculated the 4.7 or 5 μm radiant flux for every hot spot in every Galileo Near Infrared Mapping Spectrometer (NIMS) observation obtained during the Galileo mission between June 1996 and October 2001. The resulting database contains over 1000 measurements of radiant flux, corrected for emission angle, range to target, and, where necessary, incident sunlight. Io's volcanoes produce the most voluminous and most powerful eruptions in the Solar System [1] and NIMS was the ideal instrument for measuring thermal emission from these volcanoes (see [1, 2]). NIMS covered the infrared from 0.7 to 5.2 μm, so measurement of hot spot thermal emission at ~5 μm was possible even in daytime observations. As part of a campaign to quantify magnitude and variability of volcanic thermal emission [1, 3-5] we examined the entire NIMS dataset (196 observations). The resulting NIMS Io Thermal Emission Database (NITED) allows the charting of 5-μm thermal emission at individual volcanoes, identifying individual eruption episodes, and enabling the comparison of activity at different hot spots [e.g., 6] and different regions of Io. Some ionian hot spots were detected only once or twice by NIMS (e.g., Ah Peku Patera, seen during I32), but most were detected many times (e.g., Culann, Tupan and Zamama, [6]). For example, the database contains over 40 observations of Loki Patera (some at high emission angle, and two partial observations). There are 55 observations of Pele. The 27 nighttime observations of Pele show a remarkably steady 5-μm radiant flux of 35 ± 12 GW/μm. There are 34 observations of Pillan, which erupted violently in 1997. Although in many observations low spatial resolution makes it difficult to separate hot spot pairs such as Susanoo Patera and Mulungu Patera; Tawhaki Patera and Hi'iaka Patera; and Janus Patera and Kanehekili

A full-scale experimental set-up for assessing the energy performance of radiant wall and active chilled beam for cooling buildings

DEFF Research Database (Denmark)

Le Dreau, Jerome; Heiselberg, Per; Jensen, Rasmus Lund

2015-01-01

in decreasing the cooling need of the radiant wall compared to the active chilled beam. It has also been observed that the type and repartition of heat load have an influence on the cooling demand. Regarding the comfort level, both terminals met the general requirements, except at high solar heat gains......: overheating has been observed due to the absence of solar shading and the limited cooling capacity of the terminals. No local discomfort has been observed although some segments of the thermal manikin were slightly colder....

Electric radiant heating: A hot item in home comfort

Energy Technology Data Exchange (ETDEWEB)

Lemieux, G. [Britech Corp., Toronto, ON (Canada)

2003-12-01

Electric radiant heating as a floor warming system and its growing popularity in home comfort are discussed. Price can be as low as $2.00 per square foot; cost of operation may be as little as 30 cents per square foot per year, depending on time of use and local hydro rates. The use of radiant cable heating is said to have surged in popularity; it provides the same warmth and comfort as more expensive hydronic systems. Radiant cable is simple and inexpensive to install since unlike hydronic systems, it requires no complicated mechanical system with boiler, heat exchanger, valves, pumps and extensive controls. Nevertheless, prospective end users are warned to make sure that the cable is sturdy, tough, has multiple layers of protection with a thick grounding system and conductor core. In addition to heating floors, electric heating cables can also be used for snow and ice control and for melting in driveways and gutters. In these type of installations heavy duty cables are used which are installed under asphalt, concrete or interlocking stones. Thirty watts per square foot per hour is the typical requirement for melting snow and ice. Based on average electricity prices in Ontario, melting snow on an 800 square foot driveway would cost about $2.20 per hour. Assuming five hours for the system to clear the driveway, installing a heating system under the driveway could be an economically viable solution for the home owner, providing freedom from ice, the inconvenience of shovelling snow, and saving time and money.

Promoting Exit from Violent Extremism

DEFF Research Database (Denmark)

Dalgaard-Nielsen, Anja

2013-01-01

A number of Western countries are currently adding exit programs targeting militant Islamists to their counterterrorism efforts. Drawing on research into voluntary exit from violent extremism, this article identifies themes and issues that seem to cause doubt, leading to exit. It then provides a ...... the influence attempt as subtle as possible, use narratives and self-affirmatory strategies to reduce resistance to persuasion, and consider the possibility to promote attitudinal change via behavioral change as an alternative to seek to influence beliefs directly....

Cooling load calculations of radiant and all-air systems for commercial buildings

DEFF Research Database (Denmark)

Bourdakis, Eleftherios; Bauman, Fred; Schiavon, Stefano

The authors simulated in TRNSYS three radiant systems coupled with a 50% sized variable air volume (VAV) system and a 50% sized all-air VAV system with night ventilation. The objective of this study was to identify the differences in the cooling load profiles of the examined systems when they are......The authors simulated in TRNSYS three radiant systems coupled with a 50% sized variable air volume (VAV) system and a 50% sized all-air VAV system with night ventilation. The objective of this study was to identify the differences in the cooling load profiles of the examined systems when...

Effects of cryogen spray cooling and high radiant exposures on selective vascular injury during laser irradiation of human skin.

Science.gov (United States)

Tunnell, James W; Chang, David W; Johnston, Carol; Torres, Jorge H; Patrick, Charles W; Miller, Michael J; Thomsen, Sharon L; Anvari, Bahman

2003-06-01

Increasing radiant exposure offers a means to increase treatment efficacy during laser-mediated treatment of vascular lesions, such as port-wine stains; however, excessive radiant exposure decreases selective vascular injury due to increased heat generation within the epidermis and collateral damage to perivascular collagen. To determine if cryogen spray cooling could be used to maintain selective vascular injury (ie, prevent epidermal and perivascular collagen damage) when using high radiant exposures (16-30 J/cm2). Observational study. Academic hospital and research laboratory. Twenty women with normal abdominal skin (skin phototypes I-VI). Skin was irradiated with a pulsed dye laser (wavelength = 585 nm; pulse duration = 1.5 milliseconds; 5-mm-diameter spot) using various radiant exposures (8-30 J/cm2) without and with cryogen spray cooling (50- to 300-millisecond cryogen spurts). Hematoxylin-eosin-stained histologic sections from each irradiated site were examined for the degree of epidermal damage, maximum depth of red blood cell coagulation, and percentage of vessels containing perivascular collagen coagulation. Long cryogen spurt durations (>200 milliseconds) protected the epidermis in light-skinned individuals (skin phototypes I-IV) at the highest radiant exposure (30 J/cm2); however, epidermal protection could not be achieved in dark-skinned individuals (skin phototypes V-VI) even at the lowest radiant exposure (8 J/cm2). The red blood cell coagulation depth increased with increasing radiant exposure (to >2.5 mm for skin phototypes I-IV and to approximately 1.2 mm for skin phototypes V-VI). In addition, long cryogen spurt durations (>200 milliseconds) prevented perivascular collagen coagulation in all skin types. Cryogen spurt durations much longer than those currently used in therapy (>200 milliseconds) may be clinically useful for protecting the epidermis and perivascular tissues when using high radiant exposures during cutaneous laser therapies

Thermal Comfort: An Index for Hot, Humid Asia. Educational Building Digest 12.

Science.gov (United States)

United Nations Educational, Scientific, and Cultural Organization, Bangkok (Thailand). Regional Office for Education in Asia and Oceania.

The sensation of thermal comfort is determined by a combination of air temperature, humidity of the air, rate of movement of the air, and radiant heat. This digest is intended to assist architects to design educational facilities that are as thermally comfortable as is possible without recourse to mechanical air conditioning. A nomogram is…

Measurement of radiant properties of ceramic foam

International Nuclear Information System (INIS)

Hoornstra, J.; Turecky, M.; Maatman, D.

1994-07-01

An experimental facility is described for the measurement of the normal spectral and total emissivity and transmissivity of semi-transparent materials in the temperature range of 600 C to 1200 C. The set-up was used for the measurement of radiation properties of highly porous ceramic foam which is used in low NO x radiant burners. Emissivity and transmissivity data were measured and are presented for coated and uncoated ceramic foam of different thicknesses. (orig.)

The ability of different thermal aids to reduce hypothermia in neonatal piglets

DEFF Research Database (Denmark)

Pedersen, Lene Juul; Larsen, Mona Lilian Vestbjerg; Malmkvist, Jens

2016-01-01

We investigated whether hypothermia in newborn piglets could be reduced by applying different thermal aids. The experiment was performed on 150 newborn piglets from 24 sows. Right after birth, the piglets were moved to a wire mesh cage for the first 2 h of life where they experienced 1 of 7...... floor (RadiantC; n = 22) or a slatted floor (RadiantSlat; n = 18); and provision of straw on a solid floor (Straw; n = 8). Piglets’ rectal temperature was measured both continuously and manually every 10 min for the first 2 h after birth using a thermal sensor inserted in the rectum of the piglets...... were analyzed. All statistical analyses were performed using a mixed model. All thermal aids/heat solutions resulted in a less steep drop in rectal temperature, a faster recovery, and, for the smaller piglets, also a greater average rectal temperature (except for built-in floor heating) and less time...

Characteristics of infrared thermometers manufactured in Japan and calibration methods for sky radiant emittance

International Nuclear Information System (INIS)

Wang, X.; Horiguchi, I.; Machimura, T.

1993-01-01

Infrared thermometers to measure surface temperature have been increasingly adopted in recent years. The characteristics of the IR thermometer, however, are not well known.IR thermometers manufactured in Japan systematically adjust for ambient radiation based on the internal temperature of the thermometer. If, therefore, there is a large difference between the internal temperature of the IR thermometer and the apparent temperature associated with the surrounding radiation, a large error will be induced into the measured surface temperature.The purpose of our research was to determine the characteristics and measurement errors of IR thermometers. Experiments were performed with regard to the following items: (1) Measurement errors related to the internal temperature of the IR thermometer. (2) Linearity of the output signal of the IR thermometer. (3) Response of the output signal to changes in the emissivity setting. (4) Effect of sky radiant emittance on the measured surface temperature. (5) Calibration method for the terrestrial surface.The following is a summary of the results: Measurement error is affected by the internal temperature of the IR thermometer. Measurement accuracy is improved with a controlled internal temperature of 20-30°C. The measurement error becomes larger at emissivity settings under 0.7.The measurement error outdoors was not proportional to the downward longwave radiation, but to the sky radiant temperature measured by the IR thermometer. Calibration for sky radiant emittance was improved by using the difference between sky radiant temperature and air temperature.When the surface temperature measured by the infrared thermometer is plotted against the surface temperature measured by thermocouple, the sky radiant emittance error is obtained from the Y intercept. Additionally, the difference between true temperature and output of the IR thermometer for a reference plate was compared to that obtained for vegetation, and the RMS obtained was

Radiant Energy Measurements from a Scaled Jet Engine Axisymmetric Exhaust Nozzle for a Baseline Code Validation Case

Science.gov (United States)

Baumeister, Joseph F.

1994-01-01

A non-flowing, electrically heated test rig was developed to verify computer codes that calculate radiant energy propagation from nozzle geometries that represent aircraft propulsion nozzle systems. Since there are a variety of analysis tools used to evaluate thermal radiation propagation from partially enclosed nozzle surfaces, an experimental benchmark test case was developed for code comparison. This paper briefly describes the nozzle test rig and the developed analytical nozzle geometry used to compare the experimental and predicted thermal radiation results. A major objective of this effort was to make available the experimental results and the analytical model in a format to facilitate conversion to existing computer code formats. For code validation purposes this nozzle geometry represents one validation case for one set of analysis conditions. Since each computer code has advantages and disadvantages based on scope, requirements, and desired accuracy, the usefulness of this single nozzle baseline validation case can be limited for some code comparisons.

Direct conversion of infrared radiant energy for space power applications

Science.gov (United States)

Finke, R. C.

1982-01-01

A proposed technology to convert the earth radiant energy (infrared albedo) for spacecraft power is presented. The resultant system would eliminate energy storage requirements and simplify the spacecraft design. The design and performance of a infrared rectenna is discussed.

Radiant zone heated particulate filter

Science.gov (United States)

Gonze, Eugene V [Pinckney, MI

2011-12-27

A system includes a particulate matter (PM) filter including an upstream end for receiving exhaust gas and a downstream end. A radiant zoned heater includes N zones, where N is an integer greater than one, wherein each of the N zones includes M sub-zones, where M is an integer greater than or equal to one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones, restricts exhaust gas flow in a portion of the PM filter that corresponds to the selected one of the N zones, and deactivates non-selected ones of the N zones.

Impact of boundary conditions on the development of the thermal plume above a sitting human body

DEFF Research Database (Denmark)

Zukowska, Daria; Popiolek, Zbigniew J.; Melikov, Arsen Krikor

2010-01-01

a sitting occupant. CFD predictions were performed to explain the reason for a skewness in the thermal plume above a sitting thermal manikin with realistic body shape, size, and surface temperature distribution, measured in a climate chamber with mean radiant temperature equal to the room air temperature...

Spoiled Onions: Exposing Malicious Tor Exit Relays

OpenAIRE

Winter, Philipp; Lindskog, Stefan

2014-01-01

Several hundred Tor exit relays together push more than 1 GiB/s of network traffic. However, it is easy for exit relays to snoop and tamper with anonymised network traffic and as all relays are run by independent volunteers, not all of them are innocuous. In this paper, we seek to expose malicious exit relays and document their actions. First, we monitored the Tor network after developing a fast and modular exit relay scanner. We implemented several scanning modules for detecting common attac...

16 CFR Figure 4 to Subpart A of... - Flooring Radiant Panel Tester Schematic Low Flux End, Elevation

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Flooring Radiant Panel Tester Schematic Low Flux End, Elevation 4 Figure 4 to Subpart A of Part 1209 Commercial Practices CONSUMER PRODUCT SAFETY... Standard Pt. 1209, Subpt. A, Fig. 4 Figure 4 to Subpart A of Part 1209—Flooring Radiant Panel Tester...

Understanding international exit from a non-economic and emotional perspective: the case of Taiwanese entrepreneurs exit China

OpenAIRE

Lin, Yangpei

2015-01-01

I investigate why Taiwanese entrepreneurs who have invested in China exit. Viewed from the non-economic perspective, there are three main themes in this thesis. Theme A focuses on the non-economic variables in international exit. Theme B examines how incident-generated emotions shape entrepreneur’s actions in internationalization. Theme C presents an overview of the decision-making of international exit, summarizing the finding in Theme A and Theme B and revisiting the theor...

Applicability of meteor radiant determination methods depending on orbit type. I. High-eccentric orbits

Science.gov (United States)

Svoren, J.; Neslusan, L.; Porubcan, V.

1993-07-01

It is evident that there is no uniform method of calculating meteor radiants which would yield reliable results for all types of cometary orbits. In the present paper an analysis of this problem is presented, together with recommended methods for various types of orbits. Some additional methods resulting from mathematical modelling are presented and discussed together with Porter's, Steel-Baggaley's and Hasegawa's methods. In order to be able to compare how suitable the application of the individual radiant determination methods is, it is necessary to determine the accuracy with which they approximate real meteor orbits. To verify the accuracy with which the orbit of a meteoroid with at least one node at 1 AU fits the original orbit of the parent body, we applied the Southworth-Hawkins D-criterion (Southworth, R.B., Hawkins, G.S.: 1963, Smithson. Contr. Astrophys 7, 261). D0.2 the fit is rather poor and the change of orbit unrealistic. The optimal methods with the smallest values of D for given types of orbits are shown in two series of six plots. The new method of rotation around the line of apsides we propose is very appropriate in the region of small inclinations. There is no doubt that Hasegawa's omega-adjustment method (Hasegawa, I.: 1990, Publ. Astron. Soc. Japan 42, 175) has the widest application. A comparison of the theoretical radiants with the observed radiants of seven known meteor showers is also presented.

14 CFR 25.809 - Emergency exit arrangement.

Science.gov (United States)

2010-01-01

... moveable door or hatch in the external walls of the fuselage, allowing an unobstructed opening to the... event of failure of the primary system. Manual operation of the exit (after failure of the primary... during flight. (i) Each emergency exit must have a means to retain the exit in the open position, once...

''Super-radiant'' states in intermediate energy nuclear physics

International Nuclear Information System (INIS)

Auerbach, N.

1994-01-01

A ''super-radiant'' state emerges when, under certain conditions, one or a few ''internal'' states acquire a large collective decay width due to the coupling to one or a few ''external'' decay channels. The rest of the internal states are ''stripped'' of their decay width and become long lived quasistationary states. The essentials of such mechanism and its possible role in intermediate energy nuclear physics are discussed in this work

The impact of the thermal conductivities of the color conversion elements of phosphor converted LEDs under different current driving schemes

Energy Technology Data Exchange (ETDEWEB)

Fulmek, Paul; Nicolics, Johann [Institute of Sensor & Actuator Systems, Vienna University of Technology, Gusshausstraße 27-29, A-1040 Vienna (Austria); Nemitz, Wolfgang; Schweitzer, Susanne; Sommer, Christian; Hartmann, Paul [Institute of Surface Technologies and Photonics, Joanneum Research Forschungsges mbH, Franz-Pichler Straße 30, A-8160 Weiz (Austria); Schrank, Franz [Tridonic Jennersdorf GmbH, Technologiepark 10, A-8380 Jennersdorf (Austria); Wenzl, Franz P., E-mail: Franz-Peter.Wenzl@joanneum.at [Institute of Sensor & Actuator Systems, Vienna University of Technology, Gusshausstraße 27-29, A-1040 Vienna (Austria)

2016-01-15

For a systematic approach to improve the reliability and the white light quality of phosphor converted light-emitting diodes (LEDs) it is imperative to gain a better understanding of the individual parameters that affect color temperature constancy and maintenance. By means of a combined optical and thermal simulation procedure, in this contribution we give a comprehensive discussion on the impact of different thermal conductivities of the color conversion elements (CCE) of phosphor converted LEDs on their respective thermal load for different current driving schemes. In particular we show that, while for the thermal load of CCEs with low thermal conductivities also effects due to the non-linearity between the blue radiant flux and the current have to be considered, these effects are largely diminished in case of CCEs with higher thermal conductivities. - Highlights: • We discuss the thermal load of phosphor based LEDs for different current driving. • We report on the time scales for the thermal load of phosphor based LEDs. • We report on the impact of the non-linearity of the radiant flux on the thermal load. • We discuss the impact of the thermal conductivity on the thermal load.

Analysis of Thermal Comfort in an Intelligent Building

Science.gov (United States)

Majewski, Grzegorz; Telejko, Marek; Orman, Łukasz J.

2017-06-01

Analysis of thermal comfort in the ENERGIS Building, an intelligent building in the campus of the Kielce University of Technology, Poland is the focus of this paper. For this purpose, air temperature, air relative humidity, air flow rate and carbon dioxide concentration were measured and the mean radiant temperature was determined. Thermal sensations of the students occupying the rooms of the building were evaluated with the use of a questionnaire. The students used a seven-point scale of thermal comfort. The microclimate measurement results were used to determine the Predicted Mean Vote and the Predicted Percentage Dissatisfied indices.

Thermal conductivity and expansion enhancement associated with formation of the superionic state in SrCl2

International Nuclear Information System (INIS)

Moore, J.P.; Weaver, F.J.; Graves, R.S.; McElroy, D.L.

1983-01-01

A second-order phase transition in SrCl 2 near 1000 K produces superionic conduction and is often called the Bredig transition. Fine-grained, 99% dense, SrCl 2 samples containing three volume percent TiO 2 to reduce radiant transport were used to measure the differential thermal expansion coefficient (α) by push-rod dilatometry and the thermal conductivity (lambda) by a radial heat flow method. Both properties show maxima near the Bredig transition. The peak α-value is over 75 x 10 -6 K -1 . The data obtained from the radial heat flow method show good agreement with earlier tests at low temperatures, and the high temperature results show a local enhancement of lambda if about 0.06 W/m.K. This enhancement cannot be attributed to electronic or radiant transport, but is due to a new mechanism of thermal diffusion of vacancy-anion interstitial pairs in the superionic state

Influence of increment thickness on radiant energy and microhardness of bulk-fill resin composites.

Science.gov (United States)

Karacolak, Gamze; Turkun, L Sebnem; Boyacioglu, Hayal; Ferracane, Jack L

2018-03-30

Determining the energy transferred at the bottom of eleven bulk-fill resin composites, comparing top and bottom microhardness's and evaluating the correlation between microhardness and radiant energy were aimed. Samples were placed over the bottom sensor of a visible light transmission spectrophotometer and polymerized for 20 s. The bottom and top Knoop microhardness were measured. Paired t-test and correlation analysis were used for statistics (p≤0.05). In all groups, the bottom radiant energy decreased significantly with increasing thickness. For groups of Aura 2 mm, X-tra Fil 2 and 4 mm, SDR 2 and 4 mm, X-tra Base 2 mm no significant difference was found between top and bottom microhardness. For the bottom levels of Aura, X-tra Fil, Filtek Bulk-Fill Posterior, SDR, X-tra Base groups no significant difference was found between the microhardness's of 2 and 4 mm thicknesses. For X-tra Fil, Tetric Evo Ceram Bulk-Fill, Filtek Bulk-Fill Flowable and Z100 groups radiant energy affected positively the microhardness.

Towards A Model of Identity and Role Exit

Directory of Open Access Journals (Sweden)

Jason S. Milne

2011-11-01

Full Text Available Explanations of role exit often focus on how factors associated with a specific role that affect whether the individual will exit a role or not. Other research explains how identities affect our performance in a role. However, no one has yet to demonstrate the connection between role-set factors and identities, and role exit. Using data from a survey of 940 current and former soccer referees, this paper provides a model of role exit that involves a complex of processes that include role-set factors (structural and cultural factors associated with a specific role and identity processes. Specifically, this paper demonstrates that, other than role conflict, identity processes explain the relationship between role-set factors and role exit. The model provides a beginning method for understanding the connection between identities and role exit.

Analysis of excimer laser radiant exposure effect toward corneal ablation volume at LASIK procedure

Science.gov (United States)

Adiati, Rima Fitria; Rini Rizki, Artha Bona; Kusumawardhani, Apriani; Setijono, Heru; Rahmadiansah, Andi

2016-11-01

LASIK (Laser Asissted In Situ Interlamelar Keratomilieusis) is a technique for correcting refractive disorders of the eye such as myopia and astigmatism using an excimer laser. This procedure use photoablation technique to decompose corneal tissues. Although preferred due to its efficiency, permanency, and accuracy, the inappropriate amount radiant exposure often cause side effects like under-over correction, irregular astigmatism and problems on surrounding tissues. In this study, the radiant exposure effect toward corneal ablation volume has been modelled through several processes. Data collecting results is laser data specifications with 193 nm wavelength, beam diameter of 0.065 - 0.65 cm, and fluence of 160 mJ/cm2. For the medical data, the myopia-astigmatism value, cornea size, corneal ablation thickness, and flap data are taken. The first modelling step is determining the laser diameter between 0.065 - 0.65 cm with 0.45 cm increment. The energy, power, and intensity of laser determined from laser beam area. Number of pulse and total energy is calculated before the radiant exposure of laser is obtained. Next is to determine the parameters influence the ablation volume. Regression method used to create the equation, and then the spot size is substituted to the model. The validation used is statistic correlation method to both experimental data and theory. By the model created, it is expected that any potential complications can be prevented during LASIK procedures. The recommendations can give the users clearer picture to determine the appropriate amount of radiant exposure with the corneal ablation volume necessary.

Towards a uniform specification of light therapy devices for the treatment of affective disorders and use for non-image forming effects: Radiant flux.

Science.gov (United States)

Aarts, M P J; Rosemann, A L P

2018-08-01

For treating affective disorders like SAD, light therapy is used although the underlying mechanism explaining this success remains unclear. To accelerate the research on defining the light characteristics responsible for inducing a specific effect a uniform manner for specifying the irradiance at the eye should be defined. This allows a genuine comparison between light-affect studies. An important factor impacting the irradiance at the eye are the radiant characteristics of the used light therapy device. In this study the radiant fluxes of five different light therapy devices were measured. The values were weighted against the spectral sensitivity of the five photopigments present in the human eye. A measurement was taken every five minutes to control for a potential stabilizing effect. The results show that all five devices show large differences in radiant flux. The devices equipped with blue LED lights have a much lower spectral radiant flux than the devices equipped with a fluorescent light source or a white LED. The devices with fluorescent lamps needed 30 min to stabilize to a constant radiant flux. In this study only five devices were measured. Radiant flux is just the first step to identify uniform specifications for light therapy devices. It is recommended to provide all five α-opic radiant fluxes. Preferably, the devices should come with a spectral power distribution of the radiant flux. For the devices equipped with a fluorescent lamp it is recommended to provide information on the stabilization time. Copyright © 2018 Elsevier B.V. All rights reserved.

Development of a solar thermal storage system suitable for the farmhouse heating in northeast China

Energy Technology Data Exchange (ETDEWEB)

Jang, M.K. [Shenyang Agricultural Univ., Shenyang (China)

2010-07-01

This study reported on the performance of a passive solar radiant floor heating system designed for standard energy-saving farmhouses in northeast China. Weather data in the region was analyzed in terms of solar radiation, temperature, humidity and light levels. The heating characteristics of the building materials such as windows, doors, walls and roofs were also analyzed along with the indoor thermal environment of the farmhouse. The heating load was then calculated along with the size of the thermal storage element and the area of the collector element. The passive solar radiant floor heating system was designed for heating during the winter and cooling in summer. According to the results, the heating characteristics of the system have the potential to improve farming villages environment and the use of renewable energy.

Theoretical Analysis of Interferometer Wave Front Tilt and Fringe Radiant Flux on a Rectangular Photodetector

Directory of Open Access Journals (Sweden)

Franz Konstantin Fuss

2013-09-01

Full Text Available This paper is a theoretical analysis of mirror tilt in a Michelson interferometer and its effect on the radiant flux over the active area of a rectangular photodetector or image sensor pixel. It is relevant to sensor applications using homodyne interferometry where these opto-electronic devices are employed for partial fringe counting. Formulas are derived for radiant flux across the detector for variable location within the fringe pattern and with varying wave front angle. The results indicate that the flux is a damped sine function of the wave front angle, with a decay constant of the ratio of wavelength to detector width. The modulation amplitude of the dynamic fringe pattern reduces to zero at wave front angles that are an integer multiple of this ratio and the results show that the polarity of the radiant flux changes exclusively at these multiples. Varying tilt angle causes radiant flux oscillations under an envelope curve, the frequency of which is dependent on the location of the detector with the fringe pattern. It is also shown that a fringe count of zero can be obtained for specific photodetector locations and wave front angles where the combined effect of fringe contraction and fringe tilt can have equal and opposite effects. Fringe tilt as a result of a wave front angle of 0.05° can introduce a phase measurement difference of 16° between a photodetector/pixel located 20 mm and one located 100 mm from the optical origin.

Exit or revival?

International Nuclear Information System (INIS)

Anon.

2001-01-01

The answer given by the international representative at the colloquium:'nuclear: exit or revival? ' was tending towards the revival. The international, democratic, ecological and of energy policy stakes are tackled. (N.C.)

Exit from Synchrony in Joint Improvised Motion.

Directory of Open Access Journals (Sweden)

Assi Dahan

Full Text Available Motion synchrony correlates with effective and well-rated human interaction. However, people do not remain locked in synchrony; Instead, they repeatedly enter and exit synchrony. In many important interactions, such as therapy, marriage and parent-infant communication, it is the ability to exit and then re-enter synchrony that is thought to build strong relationship. The phenomenon of entry into zero-phase synchrony is well-studied experimentally and in terms of mathematical modeling. In contrast, exit-from-synchrony is under-studied. Here, we focus on human motion coordination, and examine the exit-from-synchrony phenomenon using experimental data from the mirror game paradigm, in which people perform joint improvised motion, and from human tracking of computer-generated stimuli. We present a mathematical mechanism that captures aspects of exit-from-synchrony in human motion. The mechanism adds a random motion component when the accumulated velocity error between the players is small. We introduce this mechanism to several models for human coordinated motion, including the widely studied HKB model, and the predictor-corrector model of Noy, Dekel and Alon. In all models, the new mechanism produces realistic simulated behavior when compared to experimental data from the mirror game and from tracking of computer generated stimuli, including repeated entry and exit from zero-phase synchrony that generates a complexity of motion similar to that of human players. We hope that these results can inform future research on exit-from-synchrony, to better understand the dynamics of coordinated action of people and to enhance human-computer and human-robot interaction.

Assessment of exit block following pulmonary vein isolation: far-field capture masquerading as entrance without exit block.

Science.gov (United States)

Vijayaraman, Pugazhendhi; Dandamudi, Gopi; Naperkowski, Angela; Oren, Jess; Storm, Randle; Ellenbogen, Kenneth A

2012-10-01

Complete electrical isolation of pulmonary veins (PVs) remains the cornerstone of ablation therapy for atrial fibrillation. Entrance block without exit block has been reported to occur in 40% of the patients. Far-field capture (FFC) can occur during pacing from the superior PVs to assess exit block, and this may appear as persistent conduction from PV to left atrium (LA). To facilitate accurate assessment of exit block. Twenty consecutive patients with symptomatic atrial fibrillation referred for ablation were included in the study. Once PV isolation (entrance block) was confirmed, pacing from all the bipoles on the Lasso catheter was used to assess exit block by using a pacing stimulus of 10 mA at 2 ms. Evidence for PV capture without conduction to LA was necessary to prove exit block. If conduction to LA was noticed, pacing output was decreased until there was PV capture without conduction to LA or no PV capture was noted to assess for far-field capture in both the upper PVs. All 20 patients underwent successful isolation (entrance block) of all 76 (4 left common PV) veins: mean age 58 ± 9 years; paroxysmal atrial fibrillation 40%; hypertension 70%, diabetes mellitus 30%, coronary artery disease 15%; left ventricular ejection fraction 55% ± 10%; LA size 42 ± 11 mm. Despite entrance block, exit block was absent in only 16% of the PVs, suggesting persistent PV to LA conduction. FFC of LA appendage was noted in 38% of the left superior PVs. FFC of the superior vena cava was noted in 30% of the right superior PVs. The mean pacing threshold for FFC was 7 ± 4 mA. Decreasing pacing output until only PV capture (loss of FFC) is noted was essential to confirm true exit block. FFC of LA appendage or superior vena cava can masquerade as persistent PV to LA conduction. A careful assessment for PV capture at decreasing pacing output is essential to exclude FFC. Copyright © 2012 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Tritium in Exit Signs | RadTown USA | US EPA

Science.gov (United States)

2017-08-07

Many exit signs contain tritium to light the sign without batteries or electricity. Using tritium in exit signs allows the sign to remain lit if the power goes out. Tritium is most dangerous when it is inhaled or swallowed. Never tamper with a tritium exit sign. If a tritium exit sign is broken, leave the area immediately and notify the building maintenance staff.

Entry and Exit Dynamics of Nascent Business Owners

DEFF Research Database (Denmark)

Rocha, Vera; Carneiro, Anabela; Varum, Celeste

2015-01-01

results suggest that different exit modes can be predicted by business owners’ entry route. Furthermore, different exit modes exhibit different duration dependence patterns according to the entry mode. Additionally, the paper shows that businesses started after a displacement episode are not necessarily......This paper reports a comprehensive study on the dynamics of nascent business owners using a unique longitudinal matched employer–employee dataset. We follow over 157,000 individuals who leave paid employment and become business owners during the period 1992–2007. The contributions of this paper...... are twofold. First, we analyze both entry and exit, identifying and characterizing different profiles of individuals leaving paid employment to become business owners, and distinguishing exits by dissolution from exits by ownership transfer. Second, we provide new evidence on how particular experiences...

Process evaluation of the RaDIANT community study: a dialysis facility-level intervention to increase referral for kidney transplantation.

Science.gov (United States)

Hamoda, Reem E; Gander, Jennifer C; McPherson, Laura J; Arriola, Kimberly J; Cobb, Loren; Pastan, Stephen O; Plantinga, Laura; Browne, Teri; Hartmann, Erica; Mulloy, Laura; Zayas, Carlos; Krisher, Jenna; Patzer, Rachel E

2018-01-15

The Reducing Disparities in Access to kidNey Transplantation Community Study (RaDIANT) was an End-Stage Renal Disease (ESRD) Network 6-developed, dialysis facility-level randomized trial testing the effectiveness of a 1-year multicomponent education and quality improvement intervention in increasing referral for kidney transplant evaluation among selected Georgia dialysis facilities. To assess implementation of the RaDIANT intervention, we conducted a process evaluation at the conclusion of the intervention period (January-December 2014). We administered a 20-item survey to the staff involved with transplant education in 67 dialysis facilities randomized to participate in intervention activities. Survey items assessed facility participation in the intervention (fidelity and reach), helpfulness and willingness to continue intervention activities (sustainability), suggestions for improving intervention components (sustainability), and factors that may have influenced participation and study outcomes (context). We defined high fidelity to the intervention as completing 11 or more activities, and high participation in an activity as having at least 75% participation across intervention facilities. Staff from 65 of the 67 dialysis facilities completed the questionnaire, and more than half (50.8%) reported high adherence (fidelity) to RaDIANT intervention requirements. Nearly two-thirds (63.1%) of facilities reported that RaDIANT intervention activities were helpful or very helpful, with 90.8% of facilities willing to continue at least one intervention component beyond the study period. Intervention components with high participation emphasized staff and patient-level education, including in-service staff orientations, patient and family education programs, and patient educational materials. Suggested improvements for intervention activities emphasized addressing financial barriers to transplantation, with financial education materials perceived as most helpful among RaDIANT

Impacts of a jet's exit flow pattern on mixing and combustion performance

Energy Technology Data Exchange (ETDEWEB)

Nathan, G J; Mi, J; Newbold, G J.R.; Nobes, D S [Turbulence, Energy and Combustion Group, School of Mechanical Engineering, The University of Adelaide, South Australia 5005 (Australia); Alwahabi, Z T [Turbulence, Energy and Combustion Group, Chemical Engineering, The University of Adelaide, South Australia 5005 (Australia)

2006-09-15

fine to the larger scales, can be beneficial for combustion in applications where high radiant heat transfer is desirable. Precessing and flapping jets are found to cause an increase in flame volume relative to an equivalent simple jet (SJ), implying lower molecular mixing rates. However, importantly, this decrease in mixing is achieved with no increase in the flame length. Rather the width to length ratio of these flames is increased significantly. This is of practical significance because the length of a flame is often the limiting dimension in industrial systems. The reduced strain-rates lead to an increased presence of soot within the flame, while not, in general, significantly influencing the emission of soot from the flame. The increased volume of soot leads to increased radiation, which in turn acts to reduce flame temperature, so lowering thermal NO{sub x} emissions through a global residence time-temperature reduction. For example, in full-scale cement kilns these burner nozzles are found to reduce NO{sub x} emissions by around 40-60% and increase fuel efficiency (or output) by around 5-10%. (author)

Exploring the Reasons and Ways to Exit: The Entrepreneur Perspective

NARCIS (Netherlands)

Parastuty, Zulaicha; Breitenecker, Robert J.; Schwarz, Erich J.; Harms, Rainer; Bögenhold, Dieter; Bonnet, Jean; Dejardin, Marcus; Garcia Perez de Lema, Domingo

2016-01-01

Research on entrepreneurial exit has received growing attention recently, attributing to the importance of exit in the entrepreneurial process. Yet, the complex phenomena of exit render the research scattered in the field. This research is aimed at understanding entrepreneurial exit at the

The Political Economy of Early Exit

DEFF Research Database (Denmark)

Schmitt, Carina; Starke, Peter

2016-01-01

Large-scale exit from the labour market began in the 1970s in many OECD countries. The literature indicates that individual early retirement decisions are facilitated by generous and accessible ‘pathways’ into retirement in the public pension system, unemployment insurance or disability benefits....... in the tradable sector, against a more traditional class-based logic of welfare state policy-making. Quantitative analysis of employment outcomes in 21 countries shows that the political economy of early exit clearly rests on the sectoral politics of cost-shifting.......Large-scale exit from the labour market began in the 1970s in many OECD countries. The literature indicates that individual early retirement decisions are facilitated by generous and accessible ‘pathways’ into retirement in the public pension system, unemployment insurance or disability benefits....... It is unclear, however, why early exit became so much more prevalent in some countries than in others and why such differences remain, despite a recent shift back towards higher employment rates and ‘active ageing’. We test a logic of sectoral cost-shifting politics involving cross-class alliances...

Thermal history and comfort in a Brazilian subtropical climate: a 'cool' addiction hypothesis

OpenAIRE

Vecchi, Renata De; Cândido, Christhina Maria; Lamberts, Roberto

2016-01-01

Abstract Currently, there is a rising trend for commercial buildings to use air conditioning to provide indoor thermal comfort. This paper focuses on the impact of prolonged exposure to indoor air-conditioned environments on occupants' thermal acceptability and preferences in a mixed-mode building in Brazil. Questionnaires were administered while indoor microclimatic measurements were carried out (i.e., air temperature, radiant air temperature, air speed and humidity). Results suggest signifi...

Ten questions about radiant heating and cooling systems

DEFF Research Database (Denmark)

Rhee, Kyu-Nam; Olesen, Bjarne W.; Kim, Kwang Woo

2017-01-01

studies on RHC systems in terms of comfort, heat transfer analysis, energy simulation, control strategy, system configurations and so on. Many studies have demonstrated that the RHC system is a good solution to improve indoor environmental quality while reducing building energy consumption for heating......Radiant heating and cooling (RHC) systems are being increasingly applied not only in residential but also in non-residential buildings such as commercial buildings, education facilities, and even large scale buildings such as airport terminals. Furthermore, with the combined ventilation system used...

Dynamic behavior of radiant cooling system based on capillary tubes in walls made of high performance concrete

DEFF Research Database (Denmark)

Mikeska, Tomás; Svendsen, Svend

2015-01-01

elements made of high performance concrete. The influence of the radiant cooling system on the indoor climate of the test room in terms of the air, surface and operative temperatures and velocities was investigated.The results show that the temperature of the room air can be kept in a comfortable range...... using cooling water for the radiant cooling system with a temperature only about 4K lower than the temperature of the room air. The relatively high speed reaction of the designed system is a result of the slim construction of the sandwich wall elements made of high performance concrete. (C) 2015...... the small amount of fresh air required by standards to provide a healthy indoor environment.This paper reports on experimental analyses evaluating the dynamic behavior of a test room equipped with a radiant cooling system composed of plastic capillary tubes integrated into the inner layer of sandwich wall...

Shading effect on microclimate and thermal comfort indexes in integrated crop-livestock-forest systems in the Brazilian Midwest.

Science.gov (United States)

Karvatte, Nivaldo; Klosowski, Elcio Silvério; de Almeida, Roberto Giolo; Mesquita, Eduardo Eustáquio; de Oliveira, Caroline Carvalho; Alves, Fabiana Villa

2016-12-01

The objective of this paper was to perform a microclimate evaluation and determine the indexes of thermal comfort indexes, in sun and shade, in integrated crop-livestock-forest systems with different arrangements of eucalyptus and native trees, in the Brazilian Midwest. The experiment was conducted at Embrapa Beef Cattle in Campo Grande, state of Mato Grosso do Sul, Brazil, from July to September 2013. The evaluations were conducted on four consecutive days, from 8:00 a.m. to 5:00 p.m., local time (GMT -4:00), with 1 hour intervals, recording the microclimate parameters: air temperature (°C), black globe temperature (°C), wet bulb temperature (°C), relative humidity (%), and wind speed (m.s -1 ), for the subsequent calculation of the Temperature and Humidity Index, the Black Globe Temperature and Humidity Index, and the Radiant Thermal Load. The largest changes in microclimate parameters were found in the full sun, between 12:00 p.m. and 1:00 p.m., in less dense eucalyptus system, followed by the scattered native trees system, resulting in a maximum Temperature and Humidity Index of 81, Black Globe Temperature and Humidity Index of 88 and Radiant Thermal Load of 794 W m -2 . Therefore, it is observed that with the presence of trees in pastures were possible reductions of up to 3.7 % in Temperature and Humidity Index, 10.2 % in the Black Globe Temperature and Humidity Index, and 28.3 % of the Radiant Thermal Load in the shade. Thus, one can conclude that the presence of trees and their arrangement in the systems provide better microclimate conditions and animal thermal comfort in pastures.

29 CFR 1910.36 - Design and construction requirements for exit routes.

Science.gov (United States)

2010-07-01

... construction requirements for exit routes. (a) Basic requirements. Exit routes must meet the following design... your workplace, consult NFPA 101-2000, Life Safety Code. (c) Exit discharge. (1) Each exit discharge... route must be adequate. (1) Exit routes must support the maximum permitted occupant load for each floor...

Guide to Setting Thermal Comfort Criteria and Minimizing Energy Use in Delivering Thermal Comfort

Energy Technology Data Exchange (ETDEWEB)

Regnier, Cindy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2012-08-01

Historically thermal comfort in buildings has been controlled by simple dry bulb temperature settings. As we move into more sophisticated low energy building systems that make use of alternate systems such as natural ventilation, mixed mode system and radiant thermal conditioning strategies, a more complete understanding of human comfort is needed for both design and control. This guide will support building designers, owners, operators and other stakeholders in defining quantifiable thermal comfort parameters?these can be used to support design, energy analysis and the evaluation of the thermal comfort benefits of design strategies. This guide also contains information that building owners and operators will find helpful for understanding the core concepts of thermal comfort. Whether for one building, or for a portfolio of buildings, this guide will also assist owners and designers in how to identify the mechanisms of thermal comfort and space conditioning strategies most important for their building and climate, and provide guidance towards low energy design options and operations that can successfully address thermal comfort. An example of low energy design options for thermal comfort is presented in some detail for cooling, while the fundamentals to follow a similar approach for heating are presented.

Thermal Runaway Severity Reduction Assessment and Implementation: On Li-Ion Batteries

Science.gov (United States)

Darcy, Eric

2015-01-01

Preventing cell-cell thermal runaway propagation and flames/sparks from exiting battery enclosure is possible with proper thermal & electrical design and cell thermal runaway ejecta/effluent management and can be had with minimal mass/volume penalty.

Morteros acumuladores con parafinas microencapsuladas para el aprovechamiento de la energía solar en suelos radiantes

OpenAIRE

Zetola Vargas, Vicente Andrés

2013-01-01

Esta Tesis plantea la pregunta de si el uso de morteros con parafinas microencapsuladas combinado con colectores solares térmicos puede reducir el consumo de energías convencionales, en un sistema tradicional de suelo radiante. Se pretende contribuir al conocimiento acerca del efecto que produce en el edificio, el calor latente acumulado en suelos radiantes, utilizando morteros de cemento Portland con material de cambio de fase (PCM), en conjunto con la energía solar. Para cumplir con este pr...

Modeling of mean radiant temperature based on comparison of airborne remote sensing data with surface measured data

Science.gov (United States)

Chen, Yu-Cheng; Chen, Chih-Yu; Matzarakis, Andreas; Liu, Jin-King; Lin, Tzu-Ping

2016-06-01

Assessment of outdoor thermal comfort is becoming increasingly important due to the urban heat island effect, which strongly affects the urban thermal environment. The mean radiant temperature (Tmrt) quantifies the effect of the radiation environment on humans, but it can only be estimated based on influencing parameters and factors. Knowledge of Tmrt is important for quantifying the heat load on human beings, especially during heat waves. This study estimates Tmrt using several methods, which are based on climatic data from a traditional weather station, microscale ground surface measurements, land surface temperature (LST) and light detection and ranging (LIDAR) data measured using airborne devices. Analytical results reveal that the best means of estimating Tmrt combines information about LST and surface elevation information with meteorological data from the closest weather station. The application in this method can eliminate the inconvenience of executing a wide range ground surface measurement, the insufficient resolution of satellite data and the incomplete data of current urban built environments. This method can be used to map a whole city to identify hot spots, and can be contributed to understanding human biometeorological conditions quickly and accurately.

Use of ASTER and MODIS thermal infrared data to quantify heat flow and hydrothermal change at Yellowstone National Park

Science.gov (United States)

Vaughan, R. Greg; Keszthelyi, Laszlo P.; Lowenstern, Jacob B.; Jaworowski, Cheryl; Heasler, Henry

2012-01-01

The overarching aim of this study was to use satellite thermal infrared (TIR) remote sensing to monitor geothermal activity within the Yellowstone geothermal area to meet the missions of both the U.S. Geological Survey and the Yellowstone National Park Geology Program. Specific goals were to: 1) address the challenges of monitoring the surface thermal characteristics of the > 10,000 spatially and temporally dynamic thermal features in the Park (including hot springs, pools, geysers, fumaroles, and mud pots) that are spread out over ~ 5000 km2, by using satellite TIR remote sensing tools (e.g., ASTER and MODIS), 2) to estimate the radiant geothermal heat flux (GHF) for Yellowstone's thermal areas, and 3) to identify normal, background thermal changes so that significant, abnormal changes can be recognized, should they ever occur (e.g., changes related to tectonic, hydrothermal, impending volcanic processes, or human activities, such as nearby geothermal development). ASTER TIR data (90-m pixels) were used to estimate the radiant GHF from all of Yellowstone's thermal features and update maps of thermal areas. MODIS TIR data (1-km pixels) were used to record background thermal radiance variations from March 2000 through December 2010 and establish thermal change detection limits. A lower limit for the radiant GHF estimated from ASTER TIR temperature data was established at ~ 2.0 GW, which is ~ 30–45% of the heat flux estimated through geochemical thermometry. Also, about 5 km2 of thermal areas was added to the geodatabase of mapped thermal areas. A decade-long time-series of MODIS TIR radiance data was dominated by seasonal cycles. A background subtraction technique was used in an attempt to isolate variations due to geothermal changes. Several statistically significant perturbations were noted in the time-series from Norris Geyser Basin, however many of these did not correspond to documented thermal disturbances. This study provides concrete examples of the

Spatial signals link exit from mitosis to spindle position.

Science.gov (United States)

Falk, Jill Elaine; Tsuchiya, Dai; Verdaasdonk, Jolien; Lacefield, Soni; Bloom, Kerry; Amon, Angelika

2016-05-11

In budding yeast, if the spindle becomes mispositioned, cells prevent exit from mitosis by inhibiting the mitotic exit network (MEN). The MEN is a signaling cascade that localizes to spindle pole bodies (SPBs) and activates the phosphatase Cdc14. There are two competing models that explain MEN regulation by spindle position. In the 'zone model', exit from mitosis occurs when a MEN-bearing SPB enters the bud. The 'cMT-bud neck model' posits that cytoplasmic microtubule (cMT)-bud neck interactions prevent MEN activity. Here we find that 1) eliminating cMT- bud neck interactions does not trigger exit from mitosis and 2) loss of these interactions does not precede Cdc14 activation. Furthermore, using binucleate cells, we show that exit from mitosis occurs when one SPB enters the bud despite the presence of a mispositioned spindle. We conclude that exit from mitosis is triggered by a correctly positioned spindle rather than inhibited by improper spindle position.

Operation of heat pumps for smart grid integrated buildings with thermal energy storage

NARCIS (Netherlands)

Finck, C.J.; Li, R.; Zeiler, W.

2017-01-01

A small scale office building consisting of radiant heating, a heat pump, and a water thermal energy storage tank is implemented in an optimal control framework. The optimal control aims to minimize operational electricity costs of the heat pump based on real-time power spot market prices. Optimal

Dissuasive exit signage for building fire evacuation.

Science.gov (United States)

Olander, Joakim; Ronchi, Enrico; Lovreglio, Ruggiero; Nilsson, Daniel

2017-03-01

This work presents the result of a questionnaire study which investigates the design of dissuasive emergency signage, i.e. signage conveying a message of not utilizing a specific exit door. The work analyses and tests a set of key features of dissuasive emergency signage using the Theory of Affordances. The variables having the largest impact on observer preference, interpretation and noticeability of the signage have been identified. Results show that features which clearly negate the exit-message of the original positive exit signage are most effective, for instance a red X-marking placed across the entirety of the exit signage conveys a clear dissuasive message. Other features of note are red flashing lights and alternation of colour. The sense of urgency conveyed by the sign is largely affected by sensory inputs such as red flashing lights or other features which cause the signs to break the tendencies of normalcy. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Earth Observing System AM Spacecraft - Thermal Control Subsystem

Science.gov (United States)

Chalmers, D.; Fredley, J.; Scott, C.

1993-01-01

Mission requirements for the EOS-AM Spacecraft intended to monitor global changes of the entire earth system are considered. The spacecraft is based on an instrument set containing the Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER), Clouds and Earth's Radiant Energy System (CERES), Multiangle Imaging Spectro-Radiometer (MISR), Moderate-Resolution Imaging Spectrometer (MODIS), and Measurements of Pollution in the Troposphere (MOPITT). Emphasis is placed on the design, analysis, development, and verification plans for the unique EOS-AM Thermal Control Subsystem (TCS) aimed at providing the required environments for all the onboard equipment in a densely packed layout. The TCS design maximizes the use of proven thermal design techniques and materials, in conjunction with a capillary pumped two-phase heat transport system for instrument thermal control.

Radiant heat transfers in turbojet engines. Two applications, three levels of modeling; Transferts radiatifs dans les foyers de turboreacteurs. Deux applications, trois niveaux de modelisation

Energy Technology Data Exchange (ETDEWEB)

Schultz, J L; Desaulty, M [SNECMA, Centre de Villaroche, 77 - Moissy-Cramayel (France); Taine, J [Ecole Centrale de Paris, Laboratoire EM2C. CNRS, 92 - Chatenay-Malabry (France)

1997-12-31

Several applications linked with the dimensioning of turbojet engines require the use of modeling of radiant heat transfers. Two different applications are presented in this study: the modeling of heat transfers in the main combustion chamber, and modeling of the infrared signature of the post-combustion chamber of a military engine. In the first application, two types of radiant heat transfer modeling are presented: a global modeling based on empirical considerations and used in rapid pre-dimensioning methods, and a modeling based on a grey gases concept and combined to a ray shooting type technique allowing the determination of local radiant heat flux values. In the second application, a specific modeling of the radiant heat flux is used in the framework of a ray shooting method. Each model represents a different level of successive approximations of the radiant heat transfer adapted to flow specificities and to the performance requested. (J.S.) 16 refs.

Radiant heat transfers in turbojet engines. Two applications, three levels of modeling; Transferts radiatifs dans les foyers de turboreacteurs. Deux applications, trois niveaux de modelisation

Energy Technology Data Exchange (ETDEWEB)

Schultz, J.L.; Desaulty, M. [SNECMA, Centre de Villaroche, 77 - Moissy-Cramayel (France); Taine, J. [Ecole Centrale de Paris, Laboratoire EM2C. CNRS, 92 - Chatenay-Malabry (France)

1996-12-31

Several applications linked with the dimensioning of turbojet engines require the use of modeling of radiant heat transfers. Two different applications are presented in this study: the modeling of heat transfers in the main combustion chamber, and modeling of the infrared signature of the post-combustion chamber of a military engine. In the first application, two types of radiant heat transfer modeling are presented: a global modeling based on empirical considerations and used in rapid pre-dimensioning methods, and a modeling based on a grey gases concept and combined to a ray shooting type technique allowing the determination of local radiant heat flux values. In the second application, a specific modeling of the radiant heat flux is used in the framework of a ray shooting method. Each model represents a different level of successive approximations of the radiant heat transfer adapted to flow specificities and to the performance requested. (J.S.) 16 refs.

Experimental Study of an Integrated System with Diffuse Ceiling Ventilation and Thermally Activated Building Constructions

DEFF Research Database (Denmark)

Zhang, Chen; Yu, Tao; Heiselberg, Per

. And the thermal comfort is analyzed by draught rate vertical temperature gradient and radiant temperature asymmetry. Finally the effect of plenum and diffuse ceiling is discussed. This report mainly focuses on the experiment results and discussions. Therefore, some details about the measurement are not presented...

Thermal environment evaluation. Evaluation de l'ambiance thermique

Energy Technology Data Exchange (ETDEWEB)

Tilley, B

1988-01-01

This document describes interior thermal environment analysis and the techniques involved at three applicable stages of evaluation. They range from the study of plans and archives to physical measurement with sophisticated instrumentation. Environmental factors that influence the thermal state of the building occupant are measured. The occupant's perception of the thermal environment may also be investigated. One of the most important building functions is to isolate the occupants from adverse exterior thermal conditions and provide a productive and healthy interior environment. The thermal environment is determined by clothing level, activity level, air velocity, ambient air temperature, mean radiant temperature and moisture level. Since an optimal thermal environment may not be optimal in terms of the building's energy efficiency, the evaluation process will have to draw upon expertise in energy use and other disciplines at the stage where solutions are recommended. 16 refs., 4 figs., 2 tabs.

Determination of thermal-diffusive properties of lyophilized food products

International Nuclear Information System (INIS)

Kaplon, J.; Kramkowski, R.; Berdzik, M.

1998-01-01

Experimental results of vacuum freeze drying were presented. Water solutions of skim milk were dried under various pressures and distribution of temperature and moisture as a function of drying time were determined. Unilateral radiant heating of the material was applied. On the basis of experiment results and URIF model of vacuum freeze drying the thermal conductivity and vapour diffusion coefficients in dry layer were determined

Exit interviews to reduce turnover amongst healthcare professionals.

Science.gov (United States)

Webster, Joan; Flint, Anndrea

2014-08-19

Exit interviews are widely used in healthcare organisations to identify reasons for staff attrition, yet their usefulness in limiting turnover is unclear. To determine the effectiveness of various exit interview strategies in decreasing turnover rates amongst healthcare professionals. We searched the Cochrane EPOC Group Specialised Register; Cochrane Central Register of Controlled Trials (CENTRAL), Issue 11, 2012; MEDLINE, Ovid (1950- ); EMBASE, Ovid (1947- ); CINAHL, EbscoHost (1980- ), and PsycINFO, OVID (1806-) between October 31 and November 6, 2012. We also screened the reference lists of included studies and relevant reviews; and searched trial registries for planned and on-going studies. We did not restrict searches by language or publication date. Randomised controlled trials, controlled clinical trials, controlled before-after studies and interrupted time series studies comparing turnover rates between healthcare professionals who had undergone one form of exit interview with another form of exit interview or with no interview. Two review authors independently assessed trial quality and extracted data. The original search identified 1560 citations, of which we considered 19 potentially relevant. The two authors independently reviewed the abstracts of these studies and retrieved the full texts of eight studies. We excluded all eight following independent assessment; they were either interviews, commentaries on how to do an exit interview or descriptive studies about reasons for leaving. We found no studies that matched our inclusion criteria. For this first update, we screened 2220 citations and identified no new studies. Evidence about the effectiveness of exit interviews to reduce turnover is currently not available. However, exit interviews may provide useful information about the work environment which, in turn, may be useful in the development of interventions to reduce turnover.

Where the Solar system meets the solar neighbourhood: patterns in the distribution of radiants of observed hyperbolic minor bodies

Science.gov (United States)

de la Fuente Marcos, Carlos; de la Fuente Marcos, Raúl; Aarseth, Sverre J.

2018-05-01

Observed hyperbolic minor bodies might have an interstellar origin, but they can be natives of the Solar system as well. Fly-bys with the known planets or the Sun may result in the hyperbolic ejection of an originally bound minor body; in addition, members of the Oort cloud could be forced to follow inbound hyperbolic paths as a result of secular perturbations induced by the Galactic disc or, less frequently, due to impulsive interactions with passing stars. These four processes must leave distinctive signatures in the distribution of radiants of observed hyperbolic objects, both in terms of coordinates and velocity. Here, we perform a systematic numerical exploration of the past orbital evolution of known hyperbolic minor bodies using a full N-body approach and statistical analyses to study their radiants. Our results confirm the theoretical expectations that strong anisotropies are present in the data. We also identify a statistically significant overdensity of high-speed radiants towards the constellation of Gemini that could be due to the closest and most recent known fly-by of a star to the Solar system, that of the so-called Scholz's star. In addition to and besides 1I/2017 U1 (`Oumuamua), we single out eight candidate interstellar comets based on their radiants' velocities.

Exit examinations, peer academic climate, and adolescents' developmental outcomes.

Science.gov (United States)

Benner, Aprile D

2013-02-01

Implications of high school exit examination performance were examined with a sample of 672 racial/ethnic minority students. Exit examination failure in the 10th grade was negatively linked to subsequent grade point average, school engagement, and school belonging one year later, controlling for outcomes prior to taking the examination. Academically incongruent students-those who failed the exit examination but were in schools where their same-race/ethnicity peers were performing well academically-seemed to be at particular risk for struggling grades and poorer socioemotional well-being (e.g., experiencing greater depressive symptoms and loneliness). Findings contribute to the limited research base on exit examinations and highlight the links between exit examination performance and developmental outcomes beyond the oft-studied academic domain. Copyright © 2012 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Solar ultraviolet and the occupational radiant exposure of Queensland school teachers: A comparative study between teaching classifications and behavior patterns.

Science.gov (United States)

Downs, Nathan J; Harrison, Simone L; Chavez, Daniel R Garzon; Parisi, Alfio V

2016-05-01

Classroom teachers located in Queensland, Australia are exposed to high levels of ambient solar ultraviolet as part of the occupational requirement to provide supervision of children during lunch and break times. We investigated the relationship between periods of outdoor occupational radiant exposure and available ambient solar radiation across different teaching classifications and schools relative to the daily occupational solar ultraviolet radiation (HICNIRP) protection standard of 30J/m(2). Self-reported daily sun exposure habits (n=480) and personal radiant exposures were monitored using calibrated polysulphone dosimeters (n=474) in 57 teaching staff from 6 different schools located in tropical north and southern Queensland. Daily radiant exposure patterns among teaching groups were compared to the ambient UV-Index. Personal sun exposures were stratified among teaching classifications, school location, school ownership (government vs non-government), and type (primary vs secondary). Median daily radiant exposures were 15J/m(2) and 5J/m(2)HICNIRP for schools located in northern and southern Queensland respectively. Of the 474 analyzed dosimeter-days, 23.0% were found to exceed the solar radiation protection standard, with the highest prevalence found among physical education teachers (57.4% dosimeter-days), followed by teacher aides (22.6% dosimeter-days) and classroom teachers (18.1% dosimeter-days). In Queensland, peak outdoor exposure times of teaching staff correspond with periods of extreme UV-Index. The daily occupational HICNIRP radiant exposure standard was exceeded in all schools and in all teaching classifications. Copyright © 2016 Elsevier B.V. All rights reserved.

Performance Evaluation of Radiator and Radiant Floor Heating Systems for an Office Room Connected to a Ground-Coupled Heat Pump

Directory of Open Access Journals (Sweden)

Ioan Sarbu

2016-03-01

Full Text Available A ground-coupled heat pump (GCHP system used to provide the space heating for an office room is a renewable, high performance technology. This paper discusses vapour compression-based HP systems, briefly describing the thermodynamic cycle calculations, as well as the coefficient of performance (COP and CO2 emissions of a HP with an electro-compressor and compares different heating systems in terms of energy consumption, thermal comfort and environmental impact. It is focused on an experimental study performed to test the energy efficiency of the radiator or radiant floor heating system for an office room connected to a GCHP. The main performance parameters (COP and CO2 emissions are obtained for one month of operation of the GCHP system, and a comparative analysis of these parameters is presented. Additionally, two numerical simulation models of useful thermal energy and the system COP in heating mode are developed using the Transient Systems Simulation (TRNSYS software. Finally, the simulations obtained from TRNSYS software are analysed and compared to the experimental data, showing good agreement and thus validating the simulation models.

Thermal indoor environment and energy consumption in a plus-energy house: cooling season measurements

DEFF Research Database (Denmark)

Kazanci, Ongun Berk; Olesen, Bjarne W.

2015-01-01

indoor environment. For the energy consumption of the HVAC system, air-to-brine heat pump, mixing station and controller of the radiant floor, and the air handling unit were considered. The measurements were analyzed based on the achieved indoor environment category (according to EN 15251...... the floor cooling system) and increasing the ventilation rate provided a better thermal indoor environment but with increased energy consumption. The thermal indoor environment and energy performance of the house can be improved with decreased glazing area, increased thermal mass, installation of solar...

Radiant energy during infrared neural stimulation at the target structure

Science.gov (United States)

Richter, Claus-Peter; Rajguru, Suhrud; Stafford, Ryan; Stock, Stuart R.

2013-03-01

Infrared neural stimulation (INS) describes a method, by which an infrared laser is used to stimulate neurons. The major benefit of INS over stimulating neurons with electrical current is its spatial selectivity. To translate the technique into a clinical application it is important to know the energy required to stimulate the neural structure. With this study we provide measurements of the radiant exposure, at the target structure that is required to stimulate the auditory neurons. Flat polished fibers were inserted into scala tympani so that the spiral ganglion was in front of the optical fiber. Angle polished fibers were inserted along scala tympani, and rotating the beveled surface of the fiber allowed the radiation beam to be directed perpendicular to the spiral ganglion. The radiant exposure for stimulation at the modiolus for flat and angle polished fibers averaged 6.78+/-2.15 mJ/cm2. With the angle polished fibers, a 90º change in the orientation of the optical beam from an orientation that resulted in an INS-evoked maximum response, resulted in a 50% drop in the response amplitude. When the orientation of the beam was changed by 180º, such that it was directed opposite to the orientation with the maxima, minimum response amplitude was observed.

Statistical theory for estimating sampling errors of regional radiation averages based on satellite measurements

Science.gov (United States)

Smith, G. L.; Bess, T. D.; Minnis, P.

1983-01-01

The processes which determine the weather and climate are driven by the radiation received by the earth and the radiation subsequently emitted. A knowledge of the absorbed and emitted components of radiation is thus fundamental for the study of these processes. In connection with the desire to improve the quality of long-range forecasting, NASA is developing the Earth Radiation Budget Experiment (ERBE), consisting of a three-channel scanning radiometer and a package of nonscanning radiometers. A set of these instruments is to be flown on both the NOAA-F and NOAA-G spacecraft, in sun-synchronous orbits, and on an Earth Radiation Budget Satellite. The purpose of the scanning radiometer is to obtain measurements from which the average reflected solar radiant exitance and the average earth-emitted radiant exitance at a reference level can be established. The estimate of regional average exitance obtained will not exactly equal the true value of the regional average exitance, but will differ due to spatial sampling. A method is presented for evaluating this spatial sampling error.

Is the publication of exit poll results morally permissible?

DEFF Research Database (Denmark)

Sønderholm, Jørn

2016-01-01

This article is about exit polls. It addresses the question of whether or not it is morally permissible to publish exit poll results. The conclusion of the article is that an affirmative answer should be given to this question. In section 2, the master argument in favor of the moral permissibility...... of the publication of exit poll results is introduced. This is a strong argument. It is, however, argued that it might be the case that the conclusion of this argument should be rejected if there are other, and weightier, arguments against the idea that the publication of exit poll results is morally permissible....... In section 3, the strongest arguments against the moral permissibility of the publication of exit poll results are outlined and discussed. The conclusion of this section is that all these arguments fail in their intended purpose. The conclusion of the article is therefore justified....

Thermal Effect of Pulsed Laser on Human Skin

OpenAIRE

N. C. Majumdar; V. K. Kochhar

1985-01-01

An attempt has been made to derive from theoretical considerations, some idea about safety limits of exposure with regard to radiant energy skin burns. This may be regarded as a preliminary enquiry in respect of thermal tissue damage by pulsed laser radiation, since the effects of isolated single pulses from ruby laser only have been considered. The study needs to be extended to other wavelengths as well as to trains of pulses.

IPO as an Exit startegy in Management Buyouts

OpenAIRE

Sheth, Vidhi Chetan

2008-01-01

The basic subject to this research project is,IPO as an exit strategy in management buyouts. The paper provides with an understanding of the various characteristics and factors that have an impact on a buyout exit through an IPO. Discussions on the issues like the IPO versus other exit strategies, performance of a company's pre-IPO as well as post-IPO, the trends in the buyout and the IPO market, etc are done. For a better understanding and an in-depth knowledge about the topic, we have analy...

Exit by Afghanisation

DEFF Research Database (Denmark)

Holmberg, Hasse

USA’s exit-strategi fra Afghanistan har båret præg af et italesat hovedmål om overdragelse af ansvar til de nationale myndigheder i landet. Exit-strategien udmærker sig ved sin lighed med USA’s afvikling af sit engagement i Vietnam for snart et halvt århundrede siden, hvor begrebet Vietnamisation...... om national selvbestemmelse. Den amerikanske opinion spillede en afgørende rolle og afslutningen af engagementet i Vietnam kan i lige så høj grad ses som en reaktion på den massive folkelige modstand mod krigen. Omtrent 40 år efter kan Obama-administrationen notere sig en lignende negativ trend i...... Kissinger vidste, at krigen i Vietnam var tabt. Vietnamisation havde i høj grad til formål at slutte USA’s engagement på en måde, der tog hensyn til USA’s internationale renomme. Spørgsmålet er så om de mange strategiske ligheder kan overføres til samme konklusion: krigen er tabt. Briefet har til hensigt...

Entry and exit decisions under uncertainty

DEFF Research Database (Denmark)

Kongsted, Hans Christian

1996-01-01

This paper establishes the general deterministic limit that corresponds to Dixit's model of entry and exit decisions under uncertainty. The interlinked nature of decisions is shown to be essential also in the deterministic limit. A numerical example illustrates the result......This paper establishes the general deterministic limit that corresponds to Dixit's model of entry and exit decisions under uncertainty. The interlinked nature of decisions is shown to be essential also in the deterministic limit. A numerical example illustrates the result...

Thermal environment in a simulated double office room with convective and radiant cooling systems

DEFF Research Database (Denmark)

Mustakallio, Panu; Bolashikov, Zhecho Dimitrov; Rezgals, Lauris

2017-01-01

anddraught rate was calculated. Manikin-based equivalent temperature (MBET) was determined by using two thermal manikins. CCMV provided slightly more uniform thermal environment and the least sensitive to different workstation layouts than the other systems. CB provided a bit higher draught rate levels than...

Impacts of a jet's exit flow pattern on mixing and combustion performance

Energy Technology Data Exchange (ETDEWEB)

Nathan, G.J.; Mi, J.; Newbold, G.J.R.; Nobes, D.S. [Turbulence, Energy and Combustion Group, School of Mechanical Engineering, The University of Adelaide, South Australia 5005 (Australia); Alwahabi, Z.T. [Turbulence, Energy and Combustion Group, Chemical Engineering, The University of Adelaide, South Australia 5005 (Australia)

2006-09-15

energy from the fine to the larger scales, can be beneficial for combustion in applications where high radiant heat transfer is desirable. Precessing and flapping jets are found to cause an increase in flame volume relative to an equivalent simple jet (SJ), implying lower molecular mixing rates. However, importantly, this decrease in mixing is achieved with no increase in the flame length. Rather the width to length ratio of these flames is increased significantly. This is of practical significance because the length of a flame is often the limiting dimension in industrial systems. The reduced strain-rates lead to an increased presence of soot within the flame, while not, in general, significantly influencing the emission of soot from the flame. The increased volume of soot leads to increased radiation, which in turn acts to reduce flame temperature, so lowering thermal NO{sub x} emissions through a global residence time-temperature reduction. For example, in full-scale cement kilns these burner nozzles are found to reduce NO{sub x} emissions by around 40-60% and increase fuel efficiency (or output) by around 5-10%. (author)

Jet Exit Rig Six Component Force Balance

Science.gov (United States)

Castner, Raymond; Wolter, John; Woike, Mark; Booth, Dennis

2012-01-01

A new six axis air balance was delivered to the NASA Glenn Research Center. This air balance has an axial force capability of 800 pounds, primary airflow of 10 pounds per second, and a secondary airflow of 3 pounds per second. Its primary use was for the NASA Glenn Jet Exit Rig, a wind tunnel model used to test both low-speed, and high-speed nozzle concepts in a wind tunnel. This report outlines the installation of the balance in the Jet Exit Rig, and the results from an ASME calibration nozzle with an exit area of 8 square-inches. The results demonstrated the stability of the force balance for axial measurements and the repeatability of measurements better than 0.20 percent.

Criticality safety analysis of a calciner exit chute

International Nuclear Information System (INIS)

Haught, C.F.; Basoglu, B.; Brewer, R.W.; Hollenback, D.F.; Wilkinson, A.D.; Dodds, H.L.

1994-01-01

Calcination of uranyl nitrate into uranium oxide is part of normal operations of some enrichment plants. Typically, a calciner discharges uranium oxide powder (U 3 O 8 ) into an exit chute that directs the powder into a receiving can located in a glove box. One possible scenario for a criticality accident is the exit chute becoming blocked with powder near its discharge. The blockage restricts the flow of powder causing the exit chute to become filled with the powder. If blockage does occur, the height of the powder could reach a level that would not be safe from a criticality point of view. In this analysis, the subcritical height limit is examined for 98% enriched U 3 O 8 in the exit chute with full water reflection and optimal water moderation. The height limit for ensuring criticality safety during such an accumulation is 28.2 cm above the top of the discharge pipe at the bottom of the chute. Chute design variations are also evaluated with full water reflection and optimal water moderation. Subcritical configurations for the exit chute variation are developed, but the configurations are not safe when combined with the calciner. To ensure criticality safety, modifications must be made to the calciner tube or safety measures must be implemented if these designs are to be utilized with 98% enriched material. A geometrically safe configuration for the exit chute is developed for a blockage of 20% enriched powder with full water reflection and optimal water moderation, and this configuration is safe when combined with the existing calciner

Cryogenic Thermal Absorptance Measurements on Small-Diameter Stainless Steel Tubing

Science.gov (United States)

Tuttle, James; Jahromi, Amir; Canavan, Edgar; DiPirro, Michael

2015-01-01

The Mid Infrared Instrument (MIRI) on the James Webb Space Telescope includes a mechanical cryocooler which cools its detectors to their 6 Kelvin operating temperature. The coolant gas flows through several meters of small-diameter stainless steel tubing, which is exposed to thermal radiation from its environment. Over much of its length this tubing is gold-plated to minimize the absorption of this radiant heat. In order to confirm that the cryocooler will meet MIRI's requirements, the thermal absorptance of this tubing was measured as a function of its environment temperature. We describe the measurement technique and present the results.

24 CFR 3280.106 - Exit facilities; egress windows and devices.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Exit facilities; egress windows and... § 3280.106 Exit facilities; egress windows and devices. (a) Every room designed expressly for sleeping purposes, unless it has an exit door (see § 3280.105), shall have at least one outside window or approved...

An Identity Theory of Role Exit among Soccer Referees

OpenAIRE

Milne, Jason Syme

2006-01-01

This study examines how identity processes affect role exit. I test a model of role exit that situates the identity processes of cognitive processes (reflected appraisals and social comparisons), rewards and costs related to the role, commitment to the role, and identity centrality as mediating factors between role-set and social characteristic background factors, and role exit. Using a sample of 940 current and former soccer referees in Virginia and the District of Columbia, the results s...

The efficacy of radiant heat controls on workers' heat stress around the blast furnace of a steel industry.

Science.gov (United States)

Giahi, Omid; Darvishi, Ebrahim; Aliabadi, Mohsen; Khoubi, Jamshid

2015-01-01

Workers' exposure to excessive heat in molten industries is mainly due to radiant heat from hot sources. The aim of this study was to evaluate the efficacy of radiant heat controls on workers heat stress around a typical blast furnace. Two main interventions were applied for reducing radiant heat around the blast furnace of a steel industry located in western Iran. These included using a heat absorbing system in the furnace body and installing reflective aluminum barrier in the main workstation. Heat stress indexes were measured before and after each intervention using the digital WBGT-meter. The results showed MRT and WBGT indexes decreased by 20 °C and 3.9 °C, respectively after using heat absorbing system and also decreased by 18.6 °C and 2.5 °C, respectively after installing a reflective barrier. These indexes decrease by 26.5 °C and 5.2 °C, respectively due to the simultaneous application of the two interventions which were statistically significant (p steel industries.

UV induced photoluminescence and thermally stimulated luminescence of ThO2:Tb3+ phosphor

International Nuclear Information System (INIS)

Godbole, S.V.; Nagpal, J.S.; Page, A.G.

2000-01-01

Thorium oxide doped with trivalent terbium ions offers itself as a novel phosphor with its photo- and thermally-stimulated luminescence (PL and TSL) characteristics showing a marked change on sustained exposure to 254 and 365 nm ultraviolet (UV) radiation. The reduction in luminescence intensity of Tb 3+ ions, on irradiation with 254 nm photons and subsequent restoration on exposure to 365 nm, has been correlated with the complimentary behaviour in UV-induced TSL. These changes are, in turn, ascribed to inter-configurational (f-d) transitions and e-h formation and recombination processes. UV radiation induced TSL output increases linearly with incident UV radiant energy at a constant radiation flux; however, for a fixed exposure, TSL output increases with increase in radiant flux

Effects of growth conditions on thermal profiles during Czochralski silicon crystal growth

Science.gov (United States)

Choe, Kwang Su; Stefani, Jerry A.; Dettling, Theodore B.; Tien, John K.; Wallace, John P.

1991-01-01

An eddy current testing method was used to continuously monitor crystal growth process and investigate the effects of growth conditions on thermal profiles during Czochralski silicon crystal growth. The experimental concept was to monitor the intrinsic electrical conductivities of the growing crystal and deduce temperature values from them. In terms of the experiments, the effects of changes in growth parameters, which include the crystal and crucible rotation rates, crucible position, and pull rate, and hot-zone geometries were investigated. The results show that the crystal thermal profile could shift significantly as a function of crystal length if the closed-loop control fails to maintain a constant thermal condition. As a direct evidence to the effects of the melt flow on heat transfer processes, a thermal gradient minimum was observed when the crystal/crucible rotation combination was 20/-10 rpm cw. The thermal gradients in the crystal near the growth interface were reduced most by decreasing the pull rate or by reducing the radiant heat loss to the environment; a nearly constant axial thermal gradient was achieved when either the pull rate was decreased by half, the height of the exposed crucible wall was doubled, or a radiation shield was placed around the crystal. Under these conditions, the average axial thermal gradient along the surface of the crystal was about 4-5°C/mm. When compared to theoretical results found in literature, the axial profiles correlated well with the results of the models which included radiant interactions. However, the radial gradients estimated from three-frequency data were much higher than what were predicted by known theoretical models. This discrepancy seems to indicate that optical phenomenon within the crystal is significant and should be included in theoretical modeling.

Thermal Comfort in Simulated Office Environment with Four Convective and Radiant Cooling Systems

DEFF Research Database (Denmark)

Bolashikov, Zhecho Dimitrov; Mustakallio, Panu; Kolencíková, Sona

2013-01-01

with overhead mixing ventilation (MVRC). Whole body thermal sensation (TS) and whole body TS acceptability under the four systems in a simulated office room for one hour exposure were collected. The simulated two-man office (4.12 x 4.20 x 2.89 m, L x W x H) was kept at 26 oC room air temperature. Moderate heat...... to “neutral” compared to male, whose votes were closer to the “slightly warm” thermal sensation. The whole body TS acceptability was rated close to ''clearly acceptable'' (EN 15251-2007) and was independent of subject's gender for all tested systems....

Thermal performance of an innovative roof component

Energy Technology Data Exchange (ETDEWEB)

Dimoudi, A. [Department of Environmental Engineering, Democritus University of Thrace, Vassilisis Sofias 12, 67 100 Xanthi (Greece); Lykoudis, S. [Institute for Environmental Research and Sustainable Development, National Observatory of Athens, I. Metaxa and B. Pavlou, 152 36 Penteli (Greece); Androutsopoulos, A. [Buildings Department, Division of Energy Efficiency, Centre for Renewable Energy Sources (CRES), 19th km Marathonos Aven., 190 09 Pikermi (Greece)

2006-11-15

In this paper, the thermal performance of a ventilated roof component is investigated during the winter period. The ventilated roof component consists of a conventional roof structure - reinforced concrete with a layer of thermal insulation - an air gap that allows the movement of the ambient air and an external layer made of a prefabricated concrete slab. The experimental results of the ventilated roof component during the winter period are presented and its thermal performance is analysed. The effect of key construction parameters like the height of the air gap and the use of a radiant barrier in the air gap is also investigated. Analysis of the results showed that the performance of a ventilated roof component is comparable to a conventional structure during winter. The ventilated component is shown to be in compliance with Greek regulatory requirements in terms of U-value. (author)

Control characteristics and heating performance analysis of automatic thermostatic valves for radiant slab heating system in residential apartments

Energy Technology Data Exchange (ETDEWEB)

Ahn, Byung-Cheon [Department of Building Equipment System Engineering, Kyungwon University, Seongnam City (Korea); Song, Jae-Yeob [Graduate School, Building Equipment System Engineering, Kyungwon University, Seongnam City (Korea)

2010-04-15

Computer simulations and experiments are carried out to research the control characteristics and heating performances for a radiant slab heating system with automatic thermostatic valves in residential apartments. An electrical equivalent R-C circuit is applied to analyze the unsteady heat transfer in the house. In addition, the radiant heat transfer between slabs, ceilings and walls in the room is evaluated by enclosure analysis method. Results of heating performance and control characteristics were determined from control methods such as automatic thermostatic valves, room air temperature-sensing method, water-temperature-sensing method, proportional control method, and On-Off control method. (author)

Exit channels of autoionization resonances in atoms

International Nuclear Information System (INIS)

Krause, M.O.

1985-01-01

In many-electron atoms with open shells strong autoionization resonances occur when an electron from an inner, weakly bound subshell is excited. Usually, the resonance state lies above several ionization thresholds and, hence, will decay into more than one exit or continuum channel. Several cases are discussed in which the resonance state is induced by synchrotron radiation, and the exit channels are differentiated and characterized by the analysis of the ejected electrons

Control of the mitotic exit network during meiosis

Science.gov (United States)

Attner, Michelle A.; Amon, Angelika

2012-01-01

The mitotic exit network (MEN) is an essential GTPase signaling pathway that triggers exit from mitosis in budding yeast. We show here that during meiosis, the MEN is dispensable for exit from meiosis I but contributes to the timely exit from meiosis II. Consistent with a role for the MEN during meiosis II, we find that the signaling pathway is active only during meiosis II. Our analysis further shows that MEN signaling is modulated during meiosis in several key ways. Whereas binding of MEN components to spindle pole bodies (SPBs) is necessary for MEN signaling during mitosis, during meiosis MEN signaling occurs off SPBs and does not require the SPB recruitment factor Nud1. Furthermore, unlike during mitosis, MEN signaling is controlled through the regulated interaction between the MEN kinase Dbf20 and its activating subunit Mob1. Our data lead to the conclusion that a pathway essential for vegetative growth is largely dispensable for the specialized meiotic divisions and provide insights into how cell cycle regulatory pathways are modulated to accommodate different modes of cell division. PMID:22718910

Application of roof radiant burners in large pusher-type furnaces

Directory of Open Access Journals (Sweden)

A. Varga

2009-07-01

Full Text Available The paper deals with the application of roof flat-flame burners in the pusher-type steel slab reheating furnaces, after furnace reconstruction and replacement of conventional torch burners, with the objective to increase the efficiency of radiative heat transfer from the refractory roof to the charge. Based on observations and on measurements of the construction and process parameters under operating conditions, the advantages and disadvantages of indirectly oriented radiant heat transfer are analysed in relation to the heat transfer in classically fired furnaces.

Thermal hydraulic analysis of BWR containment venting system

International Nuclear Information System (INIS)

Baburajan, P.K.; Sharma, Prashant; Paul, U.K.; Gaikwad, Avinash

2015-01-01

Installation of additional containment filtered venting system (CFVS) is necessary to depressurize the containment to maintain its mechanical integrity due to over pressurization during severe accident condition. A typical venting system for BWR is modelled using RELAP5 and analysed to investigate the effect of various thermal hydraulic parameters on the operational parameters of the venting system. The venting system consists of piping from the containment to the scrubber tank and exit line from the scrubber tank. The scrubber tank is partially filled with water to enable the scrubbing action to remove the particulate radionuclides from the incoming containment air. The pipe line from the containment is connected to the venturi inlet and the throat of the venturi is open to the scrubber tank water inventory at designed submergence level. The exit of the venturi is open to scrubber tank water. Filters are used in the upper air space of the scrubber tank as mist separator before venting out the air into the atmosphere through the exit vent line. The effect of thermal hydraulic parameters such as inlet fluid temperature, inlet steam content and venturi submergence in the scrubber tank on the venting flow rate, exit steam content, scrubber tank inventory, overflow line and siphon breaker flow rate is analysed. Results show that inlet steam content and the venturi nozzle submergence influence the venting system parameters. (author)

Turbine-missile casing exit tests

International Nuclear Information System (INIS)

Yoshimura, H.R.; Sliter, G.E.

1978-01-01

Nuclear power plant designers are required to provide safety-related components with adequate protection against hypothetical turbine-missile impacts. In plants with a ''peninsula'' arrangement, protection is provided by installing the turbine axis radially from the reactor building, so that potential missile trajectories are not in line with the plant. In plants with a ''non-peninsula'' arrangement (turbine axis perpendicular to a radius), designers rely on the low probability of a missile strike and on the protection provided by reinforced concrete walls in order to demonstrate an adequate level of protection USNRC Regulatory Guide 1.115). One of the critical first steps in demonstrating adequacy is the determination of the energy and spin of the turbine segments as they exit the turbine casing. The spin increases the probability that a subsequent impact with a protective barrier will be off-normal and therefore less severe than the normal impact assumed in plant designs. Two full-scale turbine-missile casing exit tests which were conducted by Sandia Laboratories at their rocket-sled facility in Albuquerque, New Mexico, are described. Because of wide variations in turbine design details, postulated failure conditions, and missile exit scenarios, the conditions for the two tests were carefully selected to be as prototypical as possible, while still maintaining the well-controlled and well-characterized test conditions needed for generating benchmark data

Entry and Exit.

Science.gov (United States)

1987-03-01

1. Introduction R Analyses of industrial competition have attained a new vigor with the application of game -theoretic methods. The process of... competition is represented in models that reflect genuine struggles for entry, market power, and continuing survival. Dynamics and informational effects are...presents a few of the models developed recently to study competitive processes that affect a firm’s entry into a market , and the decision to exit. The

Exiting and Returning to the Parental Home for Boomerang Kids.

Science.gov (United States)

Sandberg-Thoma, Sara E; Snyder, Anastasia R; Jang, Bohyun Joy

2015-06-01

Young adults commonly exit from and return to the parental home, yet few studies have examined the motivation behind these exits and returns using a life course framework. Using data from the National Longitudinal Survey of Youth 1997, the authors examined associations between mental health problems and economic characteristics and exits from (n = 8,162), and returns to (n = 6,530), the parental home during the transition to adulthood. The average age of the respondents was 24 years. The authors found evidence that mental health and economic characteristics were related to home leaving and returning. Emotional distress was associated with earlier exits from, and returns to, the parental home; alcohol problems were associated with earlier returns to the parental home. The findings regarding economic resources were unexpectedly mixed. Greater economic resources were linked to delayed exits from, and earlier returns to, the parental home. The implications of these findings for young adults are discussed.

Non-uniform velocity profile mechanism for flame stabilization in a porous radiant burner

Energy Technology Data Exchange (ETDEWEB)

Catapan, R.C.; Costa, M. [Mechanical Engineering Department, Instituto Superior Tecnico, Technical University of Lisbon, Avenida Rovisco Pais, 1049-001 Lisbon (Portugal); Oliveira, A.A.M. [Mechanical Engineering Department, Federal University of Santa Catarina, Campus Universitario Professor Joao David Ferreira Lima, 88040-900 Florianopolis, SC (Brazil)

2011-01-15

Industrial processes where the heating of large surfaces is required lead to the possibility of using large surface porous radiant burners. This causes additional temperature uniformity problems, since it is increasingly difficult to evenly distribute the reactant mixture over a large burner surface while retaining its stability and keeping low pollutant emissions. In order to allow for larger surface area burners, a non-uniform velocity profile mechanism for flame stabilization in a porous radiant burner using a single large injection hole is proposed and analyzed for a double-layered burner operating in open and closed hot (laboratory-scale furnace, with temperature-controlled, isothermal walls) environments. In both environments, local mean temperatures within the porous medium have been measured. For lower reactant flow rate and ambient temperature the flame shape is conical and anchored at the rim of the injection hole. As the volumetric flow rate or furnace temperature is raised, the flame undergoes a transition to a plane flame stabilized near the external burner surface. However, the stability range envelope remains the same in both regimes. (author)

Treatment of hazardous wastes by DC thermal plasma arc discharge

International Nuclear Information System (INIS)

Toru, Iwao; Yafang, Liu; Furuta, N.; Tsuginori, Inaba

2001-01-01

The temperature of the DC thermal plasma arc discharge is discussed, and examples of the waste treatment for the inorganic compounds such as fly ash, asbestos, and for the organic compounds such as the toxic dioxines and TBT by using the DC plasma arc discharge are shown. In addition, the plasma treatment by using a radiant power emitted from the DC plasma arc discharge is also shown as another new kind of ones. (authors)

Prediction of liquid metal alloy radiant properties from measurements of the Hall coefficient and the direct current resistivity

International Nuclear Information System (INIS)

Havstad, M.A.; Qiu, T.

1995-04-01

The thermal radiative properties of high temperature solid and liquid metal alloys are particularly useful to research and development efforts in laser cladding and machining, electron beam welding and laser isotope separation. However the cost, complexity, and difficulty of measuring these properties have forced the use of crude estimates from the Hagen-Rubens relation, the Drude relations, or extrapolation from low temperature or otherwise flawed data (e.g., oxidized). The authors have found in this work that published values for the Hall coefficient and the electrical resistivity of liquid metal alloys can provide useful estimates of the reflectance and emittance of some groups of binary liquid metal and high temperature solid alloys. The estimation method computes the Drude free electron parameters, and thence the optical constants and the radiant properties from the dependence of the Hall coefficient and direct current resistivity on alloy composition (the Hall coefficient gives the free electron density and the resistivity gives the average time between collisions). They find that predictions of the radiant properties of molten cerium-copper alloy, which use the measured variations in the Hall coefficient and resistivity (both highly nonlinear) as a function of alloy fraction (rather than linear combinations of the values of the pure elements) yield a good comparison to published measurements of the variation of the normal spectral emittance (a different but also nonlinear function) of cerium-copper alloy at the single wavelength available for comparison, 0.645 μm. The success of the approach in the visible range is particularly notable because one expects a Drude based approach to improve with increasing wavelength from the visible into the infrared. Details of the estimation method, the comparison between the calculation and the measured emittance, and a discussion of what groups of elements may also provide agreement is given

Shored gunshot wound of exit. A phenomenon with identity crisis.

Science.gov (United States)

Aguilar, J C

1983-09-01

Shored gunshot wound of exit is produced when the outstretched skin is impaled, sandwiched, and crushed between the outgoing bullet and the unyielding object over the exit site, thus leaving an abrasion collar on the wound margin. Proper coaptation of the wound margin is impossible because of the loss of skin just like those observed in entrance wounds. In contrast to the entrance wound, the supported exit wound shows a scalloped or punched-out abrasion collar and sharply contoured skin in between the radiating skin lacerations marginating the abrasion (Fig. 1). Should gunpowder be observed around the exit site, it is often unevenly distributed, and is not associated with searing, gunpowder stippled abrasion, tatooing, and deposition of soot.

Thermal Comfort in a Naturally-Ventilated Educational Building

Directory of Open Access Journals (Sweden)

David Mwale Ogoli

2012-11-01

Full Text Available A comprehensive study of thermal comfort in a naturally ventilated education building (88,000 ft2 in a Chicago suburb will be conducted with 120 student subjects in 2007. This paper discusses some recent trends in worldwide thermal comfort studies and presents a proposal of research for this building through a series of questionnaire tables. Two research methods used inthermal comfort studies are field studies and laboratory experiments in climate-chambers. The various elements that constitute a “comfortable” thermal environment include physical factors (ambient air temperature, mean radiant temperature, air movement and humidity, personal factors(activity and clothing, classifications (gender, age, education, etc. and psychological expectations (knowledge, experience, psychological effect of visual warmth by, say, a fireplace. Comparisons are made using data gathered from Nairobi, Kenya.Keywords: Comfort, temperature, humidity and ventilation

Radiant-and-plasma technology for coal processing

Directory of Open Access Journals (Sweden)

Vladimir Messerle

2012-12-01

Full Text Available Radiant-and-plasma technology for coal processing is presented in the article. Thermodynamic computation and experiments on plasma processing of bituminous coal preliminary electron-beam activated were fulfilled in comparison with plasma processing of the coal. Positive influence of the preliminary electron-beam activation of coal on synthesis gas yield was found. Experiments were carried out in the plasma gasifier of 100 kW power. As a result of the measurements of material and heat balance of the process gave the following integral indicators: weight-average temperature of 2200-2300 K, and carbon gasification degree of 82,4-83,2%. Synthesis gas yield at thermochemical preparation of raw coal dust for burning was 24,5% and in the case of electron-beam activation of coal synthesis gas yield reached 36,4%, which is 48% higher.

Exit and Voice: Organizational Loyalty and Dispute Resolution Strategies

Science.gov (United States)

Hoffmann, Elizabeth A.

2006-01-01

This study compares workplace dispute resolution strategies (exit, voice and toleration) in matched pairs of conventional and worker-owned cooperative organizations operating in three industries--coal mining, taxicab driving and organic food distribution. Building on Hirschman's classic exit, voice and loyalty thesis, this research demonstrates…

Radiant science, dark politics: a memoir of the nuclear age

International Nuclear Information System (INIS)

Kamen, M.D.

1985-01-01

The reviewer describes Radiant Science, Dark Politics: A Memoir of the Nuclear Age in contrast to a memoir by James R. Killian, Jr., a contemporary of Kamen. Kamen, co-discoverer of carbon-14 and a valued member of the Berkeley Radiation Laboratory, was fired in 1944 and blackballed as a security risk. Rehabilitated by the end of the war, his continued fight against political injustice through the McCarthy era colors the book and, for the reviewer, makes it self-serving. Kamen's later scientific work reflected his desire to work alone rather than in collaboration

UV induced photoluminescence and thermally stimulated luminescence of ThO{sub 2}:Tb{sup 3+} phosphor

Energy Technology Data Exchange (ETDEWEB)

Godbole, S.V.; Nagpal, J.S.; Page, A.G. E-mail: agpage@magnum.barc.ernet.in

2000-08-15

Thorium oxide doped with trivalent terbium ions offers itself as a novel phosphor with its photo- and thermally-stimulated luminescence (PL and TSL) characteristics showing a marked change on sustained exposure to 254 and 365 nm ultraviolet (UV) radiation. The reduction in luminescence intensity of Tb{sup 3+} ions, on irradiation with 254 nm photons and subsequent restoration on exposure to 365 nm, has been correlated with the complimentary behaviour in UV-induced TSL. These changes are, in turn, ascribed to inter-configurational (f-d) transitions and e-h formation and recombination processes. UV radiation induced TSL output increases linearly with incident UV radiant energy at a constant radiation flux; however, for a fixed exposure, TSL output increases with increase in radiant flux.

Lingering illness or sudden death? Pre-exit employment developments in German establishments

OpenAIRE

Fackler, Daniel; Schnabel, Claus; Wagner, Joachim

2012-01-01

Using a large administrative dataset for Germany, this paper compares employment developments in exiting and surviving establishments. For both West and East Germany we find a clear 'shadow of death' effect reflecting lingering illness: establishments shrink dramatically already several years before closure, employment growth rates differ strongly between exiting and surviving establishments, and this difference becomes stronger as exit approaches. We further show that prior to exit the workf...

Thermal history and comfort in a Brazilian subtropical climate: a 'cool' addiction hypothesis

Directory of Open Access Journals (Sweden)

Renata De Vecchi

Full Text Available Abstract Currently, there is a rising trend for commercial buildings to use air conditioning to provide indoor thermal comfort. This paper focuses on the impact of prolonged exposure to indoor air-conditioned environments on occupants' thermal acceptability and preferences in a mixed-mode building in Brazil. Questionnaires were administered while indoor microclimatic measurements were carried out (i.e., air temperature, radiant air temperature, air speed and humidity. Results suggest significant differences in occupants' thermal acceptability and cooling preferences based on thermal history; differences were found between groups based on different physical characteristics (i.e., different gender and body condition. The findings also indicated a significant potential to implement temperature fluctuations indoors when occupants are exposed to air conditioning environments in warm and humid climates.

Analysis of unexpected exits using the Fokker - Planck equation

NARCIS (Netherlands)

Herwaarden, van O.A.

1996-01-01

In this thesis exit problems are considered for stochastic dynamical systems with small random fluctuations. We study exit from a domain in the state space through a boundary, or a specified part of the boundary, that is unattainable in the underlying deterministic system. We analyze

Investigations of thermal barrier coatings of turbine parts using gas flame heating

Science.gov (United States)

Lepeshkin, A. R.; Bichkov, N. G.; Ilinskaja, O. I.; Nazarov, V. V.

2017-09-01

The development of methods for the calculated and experimental investigations thermal barrier coatings and thermal state of gas-turbine engine parts with a thermal barrier coatings is actual work. The gas flame heating was demonstrated to be effectively used during investigations of a thermal ceramic barrier coatings and thermal state of such gas-turbine engine parts with a TBC as the cooled turbine blades and vanes and combustion liner components. The gas-flame heating is considered to be preferable when investigating the gas-turbine engine parts with a TBC in the special cases when both the convective and radiant components of thermal flow are of great importance. The small-size rig with gas-flame flow made it possible to conduct the comparison investigations with the purpose of evaluating the efficiency of thermal protection of the ceramic deposited thermal barrier coatings on APS and EB techniques. The developed design-experiment method was introduced in bench tests of turbine blades and combustion liner components of gas turbine engines.

Effects of Floor Covering Resistance of a Radiant Floor on System Energy and Exergy Performances

DEFF Research Database (Denmark)

Kazanci, Ongun Berk; Shukuya, Masanori; Olesen, Bjarne W.

2016-01-01

Floor covering resistance (material and thickness) can be influenced by subjective choices (architectural design, interior design, texture, etc.) with significant effects on the performance of a radiant heating and cooling system. To study the effects of floor covering resistance on system...... performance, a water-based radiant floor heating and cooling system (dry, wooden construction) was considered to be coupled to an air-to-water heat pump, and the effects of varying floor covering resistances (0.05 m2K/W, 0.09 m2K/W and 0.15 m2K/W) on system performance were analyzed in terms of energy...... and exergy. In order to achieve the same heating and cooling outputs, higher average water temperatures are required in the heating mode (and lower temperatures in the cooling mode) with increasing floor covering resistance. These temperature requirements decrease the heat pump’s performance (lower...

Study of thermosiphon and radiant panel passive heating systems for metal buildings

Energy Technology Data Exchange (ETDEWEB)

Biehl, F.A.; Schnurr, N.M.; Wray, W.O.

1983-01-01

A study of passive-heating systems appropriate for use on metal buildings is being conducted at Los Alamos National Laboratory for the Naval Civil Engineering Laboratory, Port Hueneme, California. The systems selected for study were chosen on the basis of their appropriateness for retrofit applications, although they are also suitable for new construction: simple radiant panels that communicate directly with the building interior and a backflow thermosiphon that provides heat indirectly.

Going, Going, Gone. Innovation and Exit in Manufacturing Firms

NARCIS (Netherlands)

E. Cefis (Elena); O. Marsili (Orietta)

2007-01-01

textabstractThis paper examines the effect of innovation on the risk of exit of a firm, distinguishing between different modes of exits. Innovation represents a resource and a capability that helps a firm to build competitive advantage and remain in the market. At the same time, the resources and

Newborns' temperature submitted to radiant heat and to the Top Maternal device at birth.

Science.gov (United States)

Albuquerque, Rosemeire Sartori de; Mariani, Corintio; Bersusa, Ana Aparecida Sanches; Dias, Vanessa Macedo; Silva, Maria Izabel Mota da

2016-08-08

to compare the axillar temperatures of newborns that are put immediately after birth in skin-to-skin contact under the Top Maternal device, as compared to those in a radiant heat crib. comparatives observational study of the case-control type about temperature of 60 babies born at the Obstetric Center and Normal Delivery Center of a public hospital of the municipality of Sao Paulo, being them: 29 receiving assistance in heated crib and 31 in skin-to skin contact, shielded by a cotton tissue placed on mother's thorax, called Top Maternal. the temperature of the babies of the skin-to-skin contact group presented higher values in a larger share of the time measures verified, as compared to those that were placed in radiant heat crib, independently from the place of birth. Differences between the two groups were not statistically significant. the study contributes to generate new knowledge, supporting the idea of keeping babies with their mothers immediately after birth protected with the Maternal Top, without harming their wellbeing, as it keeps the axillar temperature in recommendable levels. comparar a temperatura axilar dos recém-nascidos acomodados - imediatamente após o nascimento - em contato pele a pele, sob o Top Maternal, em berço de calor radiante. estudo comparativo observacional do tipo Caso-Controle sobre a temperatura de 60 bebês nascidos no Centro Obstétrico e Centro de Parto Normal de um hospital público do município de São Paulo, sendo: 29 assistidos em berço aquecido e 31 em contato pele a pele, protegidos por uma malha de algodão colocada sobre o tórax da mãe, denominada Top Maternal. a temperatura dos bebês do grupo de contato pele a pele teve maior valor na maioria dos tempos verificados comparada à dos que foram colocados em berço de calor radiante, independentemente do local de nascimento. A diferença entre os grupos não foi estatisticamente significante. o estudo contribui com a geração de um novo conhecimento que sustenta a

Comparison of sources of exit fluence variation for IMRT

International Nuclear Information System (INIS)

Gardner, Joseph K; Gordon, J James; Wang Song; Siebers, Jeffrey V; Clews, Luke; Greer, Peter B

2009-01-01

The fluence exiting a patient during beam delivery can be used as treatment delivery quality assurance, either by direct comparison with expected exit fluences or by backprojection to reconstruct the patient dose. Multiple possible sources of measured exit fluence deviations exist, including changes in the beam delivery and changes in the patient anatomy. The purpose of this work is to compare the deviations caused by these sources. Machine delivery-related variability is measured by acquiring multiple dosimetric portal images (DPIs) of several test fields without a patient/phantom in the field over a time period of 2 months. Patient anatomy-related sources of fluence variability are simulated by computing transmission DPIs for a prostate patient using the same incident fluence for 11 different computed tomography (CT) images of the patient anatomy. The standard deviation (SD) and maximum deviation of the exit fluence, averaged over 5 mm x 5 mm square areas, is calculated for each test set. Machine delivery fluence SDs as large as 1% are observed for a sample patient field and as large as 2.5% for a picket-fence dMLC test field. Simulations indicate that day-to-day patient anatomy variations induce exit fluence SDs as large as 3.5%. The largest observed machine delivery deviations are 4% for the sample patient field and 7% for the picket-fence field, while the largest difference for the patient anatomy-related source is 8.5%. Since daily changes in patient anatomy can result in substantial exit fluence deviations, care should be taken when applying fluence back-projection to ensure that such deviations are properly attributed to their source. (note)

Using an electronic portal imaging device for exit dose measurements in radiotherapy

International Nuclear Information System (INIS)

Ganowicz, M.; Wozniak, B.; Bekman, A.; Maniakowski, Z.

2003-01-01

To present a method of determining the exit dose with the use of an electronic portal imaging device (EPID). The device used was the Portal Vision LC250 (Varian). The EPID signals on the central beam axis have been related to the exit dose. The exit dose measurements were performed with the ionisation chamber in the slab phantom at the distance of dose maximum from the exit surface of the phantom. EPID reading was investigated as a function of field size, phantom thickness and source-detector distance. The relation between dose rate and the EPID reading is described with empirical functions applicable to the obtained data. The exit dose is calculated from the EPID reading as a product of the calibration factor and appropriate correction factors. The determination of the exit dose rate from the EPID signal requires the knowledge of many parameters and earlier determination of essential characteristics. (author)

The determinants of firm exit in the French food industries

OpenAIRE

Blanchard, Pierre; Mathieu, Claude

2012-01-01

A semi-parametric approach is used to estimate firm propensity to exit. The unobserved individual productivity of a firm is first estimated using the Ackerberg et al. (2006) approach and then introduced as a determinant of firm exit in conjunction with other variables that may serve as barriers to exit, including the firm’s level of sunk costs and the industry concentration. Using an unbalanced panel of data for 5,849 firms in French food industries from 1996 to 2002, we find a signifi...

Congenital Cervical Teratoma: Anaesthetic Management (The EXIT Procedure

Directory of Open Access Journals (Sweden)

Ferruh Bilgin

2009-01-01

Full Text Available Ex utero intrapartum treatment (EXIT is a procedure performed during caesarean section with preservation of fetal-placental circulation, which allows the safe handling of fetal airways with risk of airways obstruction. This report aimed at describing a case of anaesthesia for EXIT in a fetus with cervical teratoma. A 30-year-old woman, 70 kg, 160 cm, gravida 2, para 1, was followed because of polyhydramniosis diagnosed at 24 weeks′ gestation. During a routine ultrasonographic examination at 35 weeks′ gestation, it was noticed that the fetus had a tumoral mass on the anterior neck, the mass had cystic and calcified components and with a size of was 10 x 6 x5 cm. The patient with physical status ASA I, was submitted to caesarean section under general anaesthesia with mechanically controlled ventilation for exutero intrapartum treatment (EXIT. Anaesthesia was induced in rapid sequence with fentanyl, propofol and rocuronium and was maintained with isoflurane in 2.5 at 3 % in O 2 and N 2 O (50%. After hysterotomy, fetus was partially released assuring uterus-placental circulation, followed by fetal laryngoscopy and tracheal intuba-tion. The infant was intubated with an uncuffed, size 2.5 endotracheal tube. Excision of the mass was performed under general anaesthesia. After surgical intervention, on the fourth postoperative day, the infant was extubated and the newborn was discharged to the pediatric neonatal unit and on the seventh day postoperatively to home without complications. Major recommendations for EXIT are maternal-fetal safety, uterine relaxation to maintain uterine volume and uterus-placental circulation, and fetal immobility to help airway handling. We report one case of cervical teratoma managed successfully with EXIT procedure.

The Effect of Exit Strategy on Optimal Portfolio Selection with Birandom Returns

Directory of Open Access Journals (Sweden)

Guohua Cao

2013-01-01

Full Text Available The aims of this paper are to use a birandom variable to denote the stock return selected by some recurring technical patterns and to study the effect of exit strategy on optimal portfolio selection with birandom returns. Firstly, we propose a new method to estimate the stock return and use birandom distribution to denote the final stock return which can reflect the features of technical patterns and investors' heterogeneity simultaneously; secondly, we build a birandom safety-first model and design a hybrid intelligent algorithm to help investors make decisions; finally, we innovatively study the effect of exit strategy on the given birandom safety-first model. The results indicate that (1 the exit strategy affects the proportion of portfolio, (2 the performance of taking the exit strategy is better than when the exit strategy is not taken, if the stop-loss point and the stop-profit point are appropriately set, and (3 the investor using the exit strategy become conservative.

30 CFR 56.4530 - Exits.

Science.gov (United States)

2010-07-01

... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Fire Prevention and Control... a sufficient number of exits to permit prompt escape in case of fire. ...

STIMULATION METHODS IMPROVEMENT OF EXIT ROUTE ON RAILWAY TRANSPORT

Directory of Open Access Journals (Sweden)

A. I. Verlan

2014-01-01

Full Text Available Purpose. The purpose of the article is to assess the costs, which are redistributed in the system «shipper−railroad−consignee» during routing of rail transportation and the development of tariff simulation methods of shippers to the exit routes formation. Methodology. Using economic and mathematical analysis the distribution of costs among the various participants of transportation process during the exit routes formation is investigated in the article. Findings. For implementation of the tariff simulation methods of exit routes and retention of the existing tariff structure it is proposed to provide in the «Tariff catalogue for freight transportation by railway transport of Ukraine» the discount, differentiated from haulage distance. A new method for determining the fees amount for cars supply and removal on approach tracks by train locomotives was also offered. Originality. As a result of the research a new method for determination of the exit rout efficiency that, unlike the existing one, takes into account the various interests of the individual participants in the transportation process was proposed. The dependence of the correction factors to the tariff for freight transportation in their own cars by direct exit routes from distance haulage was obtained. Implementation of these coefficients provides an approximation of railway tariffs to the traffic handling costs. A method for determination the rate of fees for cars supply and removal on approach tracks by train locomotives was offered. Practical value. InUkraine creation of the tariff discounts system for freight transportation by exit routes consistent with international practice and allows bringing the tariff to the real traffic handling cost. This change on the one hand will provide stimulation for private capital investments in infrastructure development and shunting means of approach tracks, on the other – it will fix the shippers to the railroads and stop their outflow

Solar radiation, phytoplankton pigments and the radiant heating of the equatorial Pacific warm pool

Science.gov (United States)

Siegel, David A.; Ohlmann, J. Carter; Washburn, Libe; Bidigare, Robert R.; Nosse, Craig T.; Fields, Erik; Zhou, Yimei

1995-01-01

Recent optical, physical, and biological oceanographic observations are used to assess the magnitude and variability of the penetrating flux of solar radiation through the mixed layer of the warm water pool (WWP) of the western equatorial Pacific Ocean. Typical values for the penetrative solar flux at the climatological mean mixed layer depth for the WWP (30 m) are approx. 23 W/sq m and are a large fraction of the climatological mean net air-sea heat flux (approx. 40 W/sq m). The penetrating solar flux can vary significantly on synoptic timescales. Following a sustained westerly wind burst in situ solar fluxes were reduced in response to a near tripling of mixed layer phytoplankton pigment concentrations. This results in a reduction in the penetrative flux at depth (5.6 W/sq m at 30 m) and corresponds to a biogeochemically mediated increase in the mixed layer radiant heating rate of 0.13 C per month. These observations demonstrate a significant role of biogeochemical processes on WWP thermal climate. We speculate that this biogeochemically mediated feedback process may play an important role in enhancing the rate at which the WWP climate system returns to normal conditions following a westerly wind burst event.

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.

Accuracy synthesis of T-shaped exit fixed mechanism in a double-crystal monochromator

International Nuclear Information System (INIS)

Wang Fengqin; Cao Chongzhen; Wang Jidai; Li Yushan; Gao Xueguan

2007-01-01

It is a key performance requirement for a double-crystal monochromator that the exit is fixed, and in order to improve the height accuracy of the exit in T-shaped exit fixed mechanism, the expression between the height of the exit and various original errors was put forward using geometrical analysis method. According to the independent action principle of original errors, accuracy synthesis of T-shaped exit fixed mechanism was studied by using the equal accuracy method, and the tolerance ranges of original errors were obtained. How to calculate the tolerance ranges of original errors was explained by giving an example. (authors)

Technological Progress, Exit and Trade

DEFF Research Database (Denmark)

Schröder, Philipp; Sørensen, Allan

productivity exporters are more likely to continue to export, and market exit is typically preceded by periods of contracting market shares. We show that the simple inclusion of exogenous economy wide technological progress into the standard Melitz (2003) model generates a tractable dynamic framework...

Do spouses coordinate their work exits? A combined survey and register analysis from Norway.

Science.gov (United States)

Syse, Astri; Solem, Per Erik; Ugreninov, Elisabeth; Mykletun, Reidar; Furunes, Trude

2014-09-01

Research on spouses' joint work exits is scarce, although household factors such as spouses' work status, marital quality, and caregiving burdens are likely to affect seniors' work engagement. We therefore examine whether the work exit probability of one spouse affects that of the other. Discrete-time hazard regression analyses of survey data linked to later registry information including all gainfully employed married respondents aged 50-74 with a working spouse (N = 1,764) were used to assess subsequent work exits. A spouse's work exit is a strong predictor of a respondent's work exit (hazard ratio 3.1, 95% confidence interval [2.5, 4.0]). Educational attainment, poor marital quality, and spouses' health and care needs do not predict work exits. Surprisingly, no gender differences are observed. Research on larger survey samples to distinguish different work exit routes and reasons for spouses' joint work exits appears warranted. To account for cultural and welfare state characteristics, cross-national studies ought to be undertaken. © The Author(s) 2013.

Experiment of cavitation erosion at the exit of a long orifice

Energy Technology Data Exchange (ETDEWEB)

Yagi, Yoshinori; Murase, Michio [Inst. of Nuclear Safety System Inc., Mihama, Fukui (Japan)

2002-09-01

We performed experiments to clarify mechanism of cavitation erosion and to predict cavitation erosion rate at the exit of a long orifice equipped at the chemical and volume control system in a pressurized water reactor (PWR). In order to find this mechanism, we used a high speed video camera. As the result, we observed bubble collapses near the exit of the orifice when flow condition was oscillating. So the bubble collapses due to the oscillation might cause the first stage erosion at the exit of the orifice. Using the orifice which had the cone-shaped exit, we observed that bubbles collapsed near the exit and then they collapsed at the upstream like a chain reaction. So this bubble collapse mechanism could be explained as follows: shock wave was generated by the bubble collapse near the exit, then it propagated upwards, consequently it caused the bubble collapse at the upstream. And we predicted erosion rate by evaluating the effect of the velocity and comparing the erosion resistance between the test speciment (aluminum) and the plant material (stainless steel) by means of vibratory tests. We compared the predicted erosion rate with that of the average value estimated from plant investigation, then we examined the applicability of these method to the plant evaluations. (author)

Resolution of thermal striping issue downstream of a horizontal pipe elbow in stratified pipe flow

International Nuclear Information System (INIS)

Kuzay, T.M.; Kasza, K.E.

1985-01-01

A thermally stratified pipe flow produced by a thermal transient when passing through a horizontal elbow as a result of secondary flow gives rise to large thermal fluctuations on the inner curvature wall of the downstream piping. These fluctuations were measured in a specially instrumented horizontal pipe and elbow system on a test set-up using water in the Mixing Components Technology Facility (MCTF) at Argonne National Laboratory (ANL). This study is part of a larger program which is studying the influence of thermal buoyancy on general reactor component performance. This paper discusses the influence of pipe flow generated thermal oscillations on the thermal stresses induced in the pipe walls. The instrumentation was concentrated around the exit plane of the 90 0 sweep elbow, since prior tests had indicated that the largest thermal fluctuations would occur within about one hydraulic diameter downstream of the elbow exit. The thermocouples were located along the inner curvature of the piping and measured the near surface fluid temperature. The test matrix involved thermal downramps under turbulent flow conditions

“Understanding exit from the founder’s business in family firms”

OpenAIRE

C. Salvato; F. Chirico; P. Sharma

2010-01-01

In this chapter we investigate the role of family-specific factors in facilitating or constraining business exit in family firms. Family business literature seems to have an implicit bias towards continuity and persistence in the founder’s business. This is explained by heavy emotional involvement and development of path-dependent core competences over generations. However, several long-lived family firms were able to successfully exit the founder’s business. Exit allowed them to free signifi...

Water-Exit Process Modeling and Added-Mass Calculation of the Submarine-Launched Missile

Directory of Open Access Journals (Sweden)

Yang Jian

2017-11-01

Full Text Available In the process that the submarine-launched missile exits the water, there is the complex fluid solid coupling phenomenon. Therefore, it is difficult to establish the accurate water-exit dynamic model. In the paper, according to the characteristics of the water-exit motion, based on the traditional method of added mass, considering the added mass changing rate, the water-exit dynamic model is established. And with help of the CFX fluid simulation software, a new calculation method of the added mass that is suit for submarine-launched missile is proposed, which can effectively solve the problem of fluid solid coupling in modeling process. Then by the new calculation method, the change law of the added mass in water-exit process of the missile is obtained. In simulated analysis, for the water-exit process of the missile, by comparing the results of the numerical simulation and the calculation of theoretical model, the effectiveness of the new added mass calculation method and the accuracy of the water-exit dynamic model that considers the added mass changing rate are verified.

Collective behavior of mice passing through an exit under panic

Science.gov (United States)

Zhang, Teng; Zhang, Xuelin; Huang, Shenshi; Li, Changhai; Lu, Shouxiang

2018-04-01

Collective movement of animal in emergency condition has attracted growing attentions among researchers. However, many rules still need to be confirmed with adequate explanation. Study of collective behavior of mice can improve our understanding about the dynamics of pedestrian movement. However, its rules still need to be confirmed with adequate explanation. In this paper, collective behavior of mice passing through an exit under panic was investigated. The results showed that the total evacuation time decreased with exit width increasing in a certain range. Based on the different tendency of the curve in temporal evolution, the process of mice flow was divided into three stages. The density of mice near the exit peaks at a certain horizontal offset and starts to decrease over time. With the increase of the exit width, the duration of the higher density state decreased. We found that the frequency of time intervals obeyed a lognormal distribution or an exponential decay for different exit widths. In addition, the relationship between the group size and the group flow rate in different scenarios was analyzed. The phenomena found in our experiments show the collective behavioral characteristic of mice under panic. Our analysis in this paper will deepen our understanding of crowd dynamics in emergency condition.

30 CFR 57.4530 - Exits for surface buildings and structures.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Exits for surface buildings and structures. 57... Fire Prevention and Control Installation/construction/maintenance § 57.4530 Exits for surface buildings and structures. Surface buildings or structures in which persons work shall have a sufficient number...

Exit, punishment and rewards in commons dilemmas: an experimental study.

Directory of Open Access Journals (Sweden)

Giangiacomo Bravo

Full Text Available Commons dilemmas are interaction situations where a common good is provided or exploited by a group of individuals so that optimal collective outcomes clash with private interests. Although in these situations, social norms and institutions exist that might help individuals to cooperate, little is known about the interaction effects between positive and negative incentives and exit options by individuals. We performed a modified public good game experiment to examine the effect of exit, rewards and punishment, as well as the interplay between exit and rewards and punishment. We found that punishment had a stronger effect than rewards on cooperation if considered by itself, whereas rewards had a stronger effect when combined with voluntary participation. This can be explained in terms of the 'framing effect', i.e., as the combination of exit and rewards might induce people to attach higher expected payoffs to cooperative strategies and expect better behaviour from others.

Study of thermal performance of capillary micro tubes integrated into the building sandwich element made of high performance concrete

DEFF Research Database (Denmark)

Mikeska, Tomas; Svendsen, Svend

2013-01-01

The thermal performance of radiant heating and cooling systems (RHCS) composed of capillary micro tubes (CMT) integrated into the inner plate of sandwich elements made of high performance concrete (HPC) was investigated in the article. Temperature distribution in HPC elements around integrated CM...... and cooling purposes of future low energy buildings. The investigations were conceived as a low temperature concept, where the difference between the temperature of circulating fluid and air in the room was kept in range of 1–4 °C.......The thermal performance of radiant heating and cooling systems (RHCS) composed of capillary micro tubes (CMT) integrated into the inner plate of sandwich elements made of high performance concrete (HPC) was investigated in the article. Temperature distribution in HPC elements around integrated CMT...... HPC layer covering the CMT. This paper shows that CMT integrated into the thin plate of sandwich element made of HPC can supply the energy needed for heating (cooling) and at the same time create the comfortable and healthy environment for the occupants. This solution is very suitable for heating...

Resolution of thermal striping issue downstream of a horizontal pipe elbow in stratified pipe flow. [LMFBR

Energy Technology Data Exchange (ETDEWEB)

Kuzay, T.M.; Kasza, K.E.

1985-01-01

A thermally stratified pipe flow produced by a thermal transient when passing through a horizontal elbow as a result of secondary flow gives rise to large thermal fluctuations on the inner curvature wall of the downstream piping. These fluctuations were measured in a specially instrumented horizontal pipe and elbow system on a test set-up using water in the Mixing Components Technology Facility (MCTF) at Argonne National Laboratory (ANL). This study is part of a larger program which is studying the influence of thermal buoyancy on general reactor component performance. This paper discusses the influence of pipe flow generated thermal oscillations on the thermal stresses induced in the pipe walls. The instrumentation was concentrated around the exit plane of the 90/sup 0/ sweep elbow, since prior tests had indicated that the largest thermal fluctuations would occur within about one hydraulic diameter downstream of the elbow exit. The thermocouples were located along the inner curvature of the piping and measured the near surface fluid temperature. The test matrix involved thermal downramps under turbulent flow conditions.

First Degree Pacemaker Exit Block

Directory of Open Access Journals (Sweden)

Johnson Francis

2016-10-01

Full Text Available Usually atrial and ventricular depolarizations follow soon after the pacemaker stimulus (spike on the ECG. But there can be an exit block due to fibrosis at the electrode - tissue interface at the lead tip. This can increase the delay between the spike and atrial or ventricular depolarization.

Exit Planning At Joost El

DEFF Research Database (Denmark)

Nellemann, Camilla

2017-01-01

This is a Danish version. This case focuses on an owner-manager's considerations regarding his exit. Carsten Joost established Joost El in 2005. It currently employs 10 people. He has two sons but no intention to hand over the business to them. Rather, he hopes that his key employee eventually...

Effects of injection nozzle exit width on rotating detonation engine

Science.gov (United States)

Sun, Jian; Zhou, Jin; Liu, Shijie; Lin, Zhiyong; Cai, Jianhua

2017-11-01

A series of numerical simulations of RDE modeling real injection nozzles with different exit widths are performed in this paper. The effects of nozzle exit width on chamber inlet state, plenum flowfield and detonation propagation are analyzed. The results are compared with that using an ideal injection model. Although the ideal injection model is a good approximation method to model RDE inlet, the two-dimensional effects of real nozzles are ignored in the ideal injection model so that some complicated phenomena such as the reflected waves caused by the nozzle walls and the reversed flow into the nozzles can not be modeled accurately. Additionally, the ideal injection model overpredicts the block ratio. In all the cases that stabilize at one-wave mode, the block ratio increases as the nozzle exit width gets smaller. The dual-wave mode case also has a relatively high block ratio. A pressure oscillation in the plenum with the same main frequency with the rotating detonation wave is observed. A parameter σ is applied to describe the non-uniformity in the plenum. σ increases as the nozzle exit width gets larger. Under some condition, the heat release on the interface of fresh premixed gas layer and detonation products can be strong enough to induce a new detonation wave. A spontaneous mode-transition process is observed for the smallest exit width case. Due to the detonation products existing in the premixed gas layer before the detonation wave, the detonation wave will propagate through reactants and products alternately, and therefore its strength will vary with time, especially near the chamber inlet. This tendency gets weaker as the injection nozzle exit width increases.

Revisit the faster-is-slower effect for an exit at a corner

Science.gov (United States)

Chen, Jun Min; Lin, Peng; Wu, Fan Yu; Li Gao, Dong; Wang, Guo Yuan

2018-02-01

The faster-is-slower effect (FIS), which means that crowd at a high enough velocity could significantly increase the evacuation time to escape through an exit, is an interesting phenomenon in pedestrian dynamics. Such phenomenon had been studied widely and has been experimentally verified in different systems of discrete particles flowing through a centre exit. To experimentally validate this phenomenon by using people under high pressure is difficult due to ethical issues. A mouse, similar to a human, is a kind of self-driven and soft body creature with competitive behaviour under stressed conditions. Therefore, mice are used to escape through an exit at a corner. A number of repeated tests are conducted and the average escape time per mouse at different levels of stimulus are analysed. The escape times do not increase obviously with the level of stimulus for the corner exit, which is contrary to the experiment with the center exit. The experimental results show that the FIS effect is not necessary a universal law for any discrete system. The observation could help the design of buildings by relocating their exits to the corner in rooms to avoid the formation of FIS effect.

Investigation of Thermal Comfort Conditions in Higher Education Facilities: A Case Study for Engineering Faculty in Edirne

Directory of Open Access Journals (Sweden)

E. Mıhlayanlar

2017-02-01

Full Text Available In this study, a higher education institution in Edirne (Trakya University Engineering Faculty is investigated for indoor thermal comfort conditions of the classrooms (indoor temperature, relative humidity, average radiant temperature, “Satisfaction from thermal environment” (PMV and “Dissatisfaction from thermal environment” (PPD. The classrooms in the institution are heated by a central heating system and utilise natural ventilation system. Measurements were taken with the proper devices at the same time of the weekdays during lecture times in winter (heating season in December. The results obtained from measurements are given in graphics and compared with the values given in ASHRAE 55 and ISO 7730 standards.

Application of an entry-exit tariff model to the gas transport system in Spain

International Nuclear Information System (INIS)

Alonso, Alejandro; Serrano, Miguel; Olmos, Luis

2010-01-01

Under an entry-exit gas tariff system, reservation of capacity is split into entry capacity, to transport gas from the injection points to a virtual balancing point, and exit capacity, to transport gas from the balancing point to the exit points in the system. Entry-exit tariff for gas transport systems have been recommended by the 3rd EU Energy Package, since they are cost reflective, facilitate gas trade and can provide signals for the location of gas injections or off-takes. The advisability of applying an entry-exit tariff system is discussed in this paper. Apart from this, authors propose an entry-exit tariff model and apply it to compute charges for the Spanish gas transport system in 2009. Results produced by the model are presented as coefficients which should multiply the current postal transport tariff. The paper concludes that entry-exit tariffs would be useful location signals which would result in a better use of the gas transport system in Spain. In those cases where demand exceeds available capacity, as it occurs at the congested connection with France, entry-exit tariffs could be supplemented by capacity charges at entry points resulting from auctions. (author)

Everolimus in advanced, progressive, well-differentiated, non-functional neuroendocrine tumors: RADIANT-4 lung subgroup analysis.

Science.gov (United States)

Fazio, Nicola; Buzzoni, Roberto; Delle Fave, Gianfranco; Tesselaar, Margot E; Wolin, Edward; Van Cutsem, Eric; Tomassetti, Paola; Strosberg, Jonathan; Voi, Maurizio; Bubuteishvili-Pacaud, Lida; Ridolfi, Antonia; Herbst, Fabian; Tomasek, Jiri; Singh, Simron; Pavel, Marianne; Kulke, Matthew H; Valle, Juan W; Yao, James C

2018-01-01

In the phase III RADIANT-4 study, everolimus improved median progression-free survival (PFS) by 7.1 months in patients with advanced, progressive, well-differentiated (grade 1 or grade 2), non-functional lung or gastrointestinal neuroendocrine tumors (NETs) vs placebo (hazard ratio, 0.48; 95% confidence interval [CI], 0.35-0.67; P < .00001). This exploratory analysis reports the outcomes of the subgroup of patients with lung NETs. In RADIANT-4, patients were randomized (2:1) to everolimus 10 mg/d or placebo, both with best supportive care. This is a post hoc analysis of the lung subgroup with PFS, by central radiology review, as the primary endpoint; secondary endpoints included objective response rate and safety measures. Ninety of the 302 patients enrolled in the study had primary lung NET (everolimus, n = 63; placebo, n = 27). Median PFS (95% CI) by central review was 9.2 (6.8-10.9) months in the everolimus arm vs 3.6 (1.9-5.1) months in the placebo arm (hazard ratio, 0.50; 95% CI, 0.28-0.88). More patients who received everolimus (58%) experienced tumor shrinkage compared with placebo (13%). Most frequently reported (≥5% incidence) grade 3-4 drug-related adverse events (everolimus vs. placebo) included stomatitis (11% vs. 0%), hyperglycemia (10% vs. 0%), and any infections (8% vs. 0%). In patients with advanced, progressive, well-differentiated, non-functional lung NET, treatment with everolimus was associated with a median PFS improvement of 5.6 months, with a safety profile similar to that of the overall RADIANT-4 cohort. These results support the use of everolimus in patients with advanced, non-functional lung NET. The trial is registered with ClinicalTrials.gov (no. NCT01524783). © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

The use of the exit interview to reduce turnover amongst healthcare professionals.

Science.gov (United States)

Flint, Anndrea; Webster, Joan

2011-01-19

Exit interviews are widely used in healthcare organisations to identify reasons for staff attrition, yet their usefulness in limiting turnover is unclear. To determine the effectiveness of various exit interview strategies in decreasing turnover rates amongst healthcare professionals. We used a comprehensive search strategy including an electronic search of the following databases: DARE, CENTRAL, MEDLINE, EMBASE, CINAHL, PsycINFO, ERIC (search date: 7 September 2010) and EPOC Specialised Register (search date: 30 September 2009). We also screened the reference lists of included studies and relevant reviews. Randomised controlled trials, controlled clinical trials, controlled before and after studies and interrupted time series studies comparing turnover rates between healthcare professionals who had undergone one form of exit interview with another form of exit interview or with no interview. Two review authors independently assessed trial quality and extracted data. The search identified 1560 citations of which we considered 19 potentially relevant. The two authors independently reviewed the abstracts of these studies and retrieved the full texts of eight studies. We excluded all eight following independent assessment. They were either interviews, commentaries on how to do an exit interview or descriptive studies about reasons for leaving. We found no trials that matched our inclusion criteria. Evidence about the effectiveness of exit interviews to reduce turnover is currently not available. However, exit interviews may provide useful information about the work environment which, in turn, may be useful in the development of interventions to reduce turnover.

Exploring the Relationship of Exit Flow and Jam Density in Panic Scenarios Using Animal Dynamics

NARCIS (Netherlands)

Sobhani, A.; Sarvi, M.; Duives, D.C.; Ejtemai, O.; Aghabayk, K.; Hoogendoorn, S.P.

2014-01-01

There are few studies investigating crowd dynamics in panic situations. They used measures such as exit flow rate to explore the exit performance in evacuation scenarios. However, there is limited research exploring the relationship of exit flow rate and density behind the exit for panic scenarios.

RCC Plug Repair Thermal Tools for Shuttle Mission Support

Science.gov (United States)

Rodriguez, Alvaro C.; Anderson, Brian P.

2010-01-01

A thermal math model for the Space Shuttle Reinforced Carbon-Carbon (RCC) Plug Repair was developed to increase the confidence in the repair entry performance and provide a real-time mission support tool. The thermal response of the plug cover plate, local RCC, and metallic attach hardware can be assessed with this model for any location on the wing leading edge. The geometry and spatial location of the thermal mesh also matches the structural mesh which allows for the direct mapping of temperature loads and computation of the thermoelastic stresses. The thermal model was correlated to a full scale plug repair radiant test. To utilize the thermal model for flight analyses, accurate predictions of protuberance heating were required. Wind tunnel testing was performed at CUBRC to characterize the heat flux in both the radial and angular directions. Due to the complexity of the implementation of the protuberance heating, an intermediate program was developed to output the heating per nodal location for all OML surfaces in SINDA format. Three Design Reference Cases (DRC) were evaluated with the correlated plug thermal math model to bound the environments which the plug repair would potentially be used.

Thermal neutrons streaming in straight duct

International Nuclear Information System (INIS)

Jehouani, A.; Boulkheir, M.; Ichaoui, R.

2000-01-01

The neutron streaming in duct is due to two phenomena: a) direct propagation and b) reflection on duct wall. We have used the Monte Carlo method to evaluate the ratio of the reflected neutrons flux by the duct wall to the total flux at the exit of the duct for iron and aluminium. Ten neutrons energy groups are considered between 10 -5 eV and 10 eV. A Fortran program is developed to evaluate the neutron double differential albedo. It is shown that the two following approximations are largely justified: i) Three collisions in the duct wall are sufficient to attain the asymptotic limit of the multiscattered neutron double differential albedo ii) The points of entry and exit of the neutron in the duct wall may be considered the same for the multiscattered neutrons. For a punctual source at the mouth of the duct, we have determined the direct and the reflected part of the total thermal neutron flux at the exit of the duct for different lengths and different radius of the duct. For a punctual source, we have found that the major contribution to the total flux of neutrons at the exit is due to the neutron reflection by walls and the reflection contribution decreases when the neutron energy decreases. For a constant length of the duct, the reflected part decreases when the duct radius increases while for the disk shaped source we have found the opposite phenomena. The transmitted neutron flux distribution at the exit of the duct are determined for disk shaped source for different neutron energy and for different distance from the exit center. (author)

Local heat transfer performance and exit flow characteristics of a miniature axial fan

International Nuclear Information System (INIS)

Stafford, Jason; Walsh, Ed; Egan, Vanessa

2010-01-01

Dimensional restrictions in electronic equipment have resulted in miniaturization of many existing cooling technologies. In addition to this, cooling solutions are required to dissipate increased thermal loads to maintain component reliability. Axial fans are widely used in electronics cooling to meet such thermal demands. However, if the extent of non-uniform heat transfer rates, produced by highly three-dimensional air patterns is unknown in the design stages, premature component failure may result. The current study highlights these non-uniformities in heat transfer coefficient, using infrared thermography of a miniature axial fan impinging air on a flat plate. Fan rotational speed and distance from the flat plate are varied to encompass heat transfer phenomena resultant from complex exit air flow distribution. Local peaks in heat transfer coefficient have been shown to be directly related to the air flow and fan motor support interaction. Optimum locations for discrete heat source positioning have been identified which are a function of fan to plate spacing and independent of fan rotational speed when the Reynolds number effect is not apparent.

Experimental study including subjective evaluations of mixing and displacement ventilation combined with radiant floor heating/cooling system

DEFF Research Database (Denmark)

Krajcik, Michal; Tomasi, Roberta; Simone, Angela

2013-01-01

Sixteen subjects evaluated the indoor environment in four experiments with different combinations of ventilation systems and radiant heating/cooling systems. In the first two tests, the simulated residential room was equipped either by a mixing ventilation system supplying warm air for space heat...

International Competition and Small-Firm Exit in US Manufacturing

OpenAIRE

Robert M Feinberg

2013-01-01

This study analyzes both the determinants of small firm exit rates in US manufacturing over the 1989–2004 period, especially the reaction of domestic firms to the nature of foreign competition as measured by industry-specific real exchange rate movements (interacted with import penetration by industry). These international pressures seem to lead to increased rates of smallest-firm exit in manufacturing, though the magnitudes of these effects are smaller than sometimes discussed. However, high...

Improved social force model based on exit selection for microscopic pedestrian simulation in subway station

Institute of Scientific and Technical Information of China (English)

郑勋; 李海鹰; 孟令云; 许心越; 陈旭

2015-01-01

An improved social force model based on exit selection is proposed to simulate pedestrians’ microscopic behaviors in subway station. The modification lies in considering three factors of spatial distance, occupant density and exit width. In addition, the problem of pedestrians selecting exit frequently is solved as follows: not changing to other exits in the affected area of one exit, using the probability of remaining preceding exit and invoking function of exit selection after several simulation steps. Pedestrians in subway station have some special characteristics, such as explicit destinations, different familiarities with subway station. Finally, Beijing Zoo Subway Station is taken as an example and the feasibility of the model results is verified through the comparison of the actual data and simulation data. The simulation results show that the improved model can depict the microscopic behaviors of pedestrians in subway station.

Design methodology and criteria for daylight and thermal comfort in nearly-zero energy office buildings in Nordic climate

DEFF Research Database (Denmark)

Karlsen, Line Røseth

The objective of this PhD thesis was to arrange for an integrated building design with respect to thermal comfort, daylighting and energy use, applicable for office buildings in Nordic climate. In order to achieve this, it is suggested that modelling of mean radiant temperature (MRT) should...... into the simulation tool IDA ICE. Furthermore, the control of solar shading is given attention, since it is a crucial link between the thermal and daylighting performance. The thesis presents results of an occupant survey with 46 subjects, which was carried out to investigate occupants’ preferences towards...

Does Business Cycle Have an Impact on Entrants and Exits?

Directory of Open Access Journals (Sweden)

Nikolay Sterev

2017-03-01

Full Text Available Purpose: The role of entrants and exits has enlarged indisputably over recent years. The basic explanation is connected to the deepening of innovation's influence on industrial growth. Furthermore, new businesses have to be more effective, and based on products, technological or organizational innovations, and exits have to be ineffective (respectively unprofitable, based on denoted products or technology. Design/methodology/approach: According to the above-mentioned prerequisites, policymakers need to manage the role (respectively the impact that entrants (new start-up companies and exits play in industrial growth. Nevertheless, this impact is not a cornerstone of the Bulgarian National Strategy, or the Europe 2020 Strategy. Findings: The paper tries to answer the following two questions: 1 Do new start-up companies and exits have any role and influence on economic growth in Bulgaria? and 2 Does the role (respectively the impact of entrants and exits in industrial growth change according to economic cycle? Research limitations/implications: In addition, according to the Lisbon Strategy, as well as the European Union's (EU Strategy 2020, the current economic policy supports entrepreneurship and innovations. Thus, the establishment of innovative companies, as well as the development of innovative, incumbent business are core issues of EU economic policy for the past decade. Originality/value: The paper builds on the industrial dynamic methodology and on the understanding of how business decisions (entrepreneurship, innovations, and R&D on micro level correspond to macro level (GDP growth and innovation policy.

The comparison of exit-site care with normal saline and povidone-iodine in preventing exit-site infection and peritonitis in children on chronic peritoneal dialysis treatment

Directory of Open Access Journals (Sweden)

Onder Yavascan

2011-01-01

Full Text Available Peritonitis and catheter exit- site infections (ESI are important causes of hospitalization and catheter loss in patients undergoing chronic peritoneal dialysis (CPD. The frequency of infection can be reduced by scrupulous exit- site care with or without topical antiseptics. There are no studies showing any benefit in the use of povidone-iodine or normal saline for care of exit- sites in long- term CPD patients. In this study, we aimed to determine the potential effectiveness of the application of povidone-iodine or normal saline at the catheter exit- site in preventing ESI and peritonitis in children on CPD. A total of 98 patients treated with either povidone-iodine or normal saline were included in this study. Group I (34 patients used povidone-iodine and group II (64 patients simply cleansed the exit- site with normal saline (0.9% NaCl. Dressings were changed 2 to 3 times in a week. The total cumulative follow- up time was 3233 patient- months. ESIs occurred in 10 (29.4% of 34 patients using povidone-iodine and in 10 (15.6% of 64 patients using normal saline. The frequency of ESI was significantly high in group I (povidone-iodine patients. The mean rate of ESI was 1 episode/60.8 patient- months for group I versus 1 episode/144 patient- months for group II (P 0.05. In conclusion, exit- site care with normal saline is an effective strategy in reducing the incidence of ESI in children on CPD. It can thus significantly reduce morbidity, catheter loss, and the need to transfer patients on peritoneal dialysis to hemodialysis.

Influence of drill helical direction on exit damage development in drilling carbon fiber reinforced plastic

Science.gov (United States)

Bai, Y.; Jia, Z. Y.; Wang, F. J.; Fu, R.; Guo, H. B.; Cheng, D.; Zhang, B. Y.

2017-06-01

Drilling is inevitable for CFRP components’ assembling process in the aviation industry. The exit damage frequently occurs and affects the load carrying capacity of components. Consequently, it is of great urgency to enhance drilling exit quality on CFRP components. The article aims to guide the reasonable choice of drill helical direction and effectively reduce exit damage. Exit observation experiments are carried out with left-hand helical, right-hand helical and straight one-shot drill drilling T800S CFRP laminates separately. The development rules of exit damage and delamination factor curves are obtained. Combined with loading conditions and fracture modes of push-out burrs, and thrust force curves, the influence of drill helical direction on exit damage development is derived. It is found that the main fracture modes for left-hand helical, right-hand helical, and straight one-shot drill are mode I, extrusive fracture, mode III respectively. Among them, mode III has the least effect on exit damage development. Meanwhile, the changing rate of thrust force is relative slow for right-hand helical and straight one-shot drill in the thrust force increasing phase of stage II, which is disadvantaged for exit damage development. Therefore, straight one-shot drill’s exit quality is the best.

Study on coal char ignition by radiant heat flux.

Science.gov (United States)

Korotkikh, A. G.; Slyusarskiy, K. V.

2017-11-01

The study on coal char ignition by CO2-continuous laser was carried out. The coal char samples of T-grade bituminous coal and 2B-grade lignite were studied via CO2-laser ignition setup. Ignition delay times were determined at ambient condition in heat flux density range 90-200 W/cm2. The average ignition delay time value for lignite samples were 2 times lower while this difference is larger in high heat flux region and lower in low heat flux region. The kinetic constants for overall oxidation reaction were determined using analytic solution of simplified one-dimensional heat transfer equation with radiant heat transfer boundary condition. The activation energy for lignite char was found to be less than it is for bituminous coal char by approximately 20 %.

Thermal engineering and micro-technology; Thermique et microtechnologie

Energy Technology Data Exchange (ETDEWEB)

Kandlikar, S. [Rochester Inst. of Tech., NY (United States); Luo, L. [Institut National Polytechnique, 54 - Nancy (France); Gruss, A. [CEA Grenoble, GRETH, 38 (France); Wautelet, M. [Mons Univ. (Belgium); Gidon, S. [CEA Grenoble, Lab. d' Electronique et de Technologie de l' Informatique (LETI), 38 (France); Gillot, C. [Ecole Nationale Superieure d' Ingenieurs Electriciens de Grenoble, 38 - Saint Martin d' Heres (France)]|[CEA Grenoble, Lab. Electronique et de Technologie de l' Informatique (LETI), 38 (France); Therme, J.; Marvillet, Ch.; Vidil, R. [CEA Grenoble, 38 (France); Dutartre, D. [ST Microelectronique, France (France); Lefebvre, Ph. [SNECMA, 75 - Paris (France); Lallemand, M. [Institut National des Sciences Appliquees (INSA), 69 - Villeurbanne (France); Colin, S. [Institut National des Sciences Appliquees (INSA), 31 - Toulouse (France); Joulin, K. [Ecole Nationale Superieure de Mecanique et d' Aerotechnique (ENSMA), 86 - Poitiers (France); Gad el Hak, M. [Virginia Univ., Charlottesville, VA (United States)

2003-07-01

This document gathers the abstracts and transparencies of 5 invited conferences of this congress of the SFT about heat transfers and micro-technologies: Flow boiling in microchannels: non-dimensional groups and heat transfer mechanisms (S. Kandlikar); Intensification and multi-scale process units (L. Luo and A. Gruss); Macro-, micro- and nano-systems: different physics? (M. Wautelet); micro-heat pipes (M. Lallemand); liquid and gas flows inside micro-ducts (S. Colin). The abstracts of the following presentations are also included: Electro-thermal writing of nano-scale memory points in a phase change material (S. Gidon); micro-technologies for cooling in micro-electronics (C. Gillot); the Minatec project (J. Therme); importance and trends of thermal engineering in micro-electronics (D. Dutartre); Radiant heat transfers at short length scales (K. Joulain); Momentum and heat transfer in micro-electromechanical systems (M. Gad-el-Hak). (J.S.)

Athermal alterations in the structure in the canalicular membrane and ATPase activity induced by thermal levels of microwave radiation

International Nuclear Information System (INIS)

Phelan, A.M.; Neubauer, C.F.; Timm, R.; Neirenberg, J.; Lange, D.G.

1994-01-01

Sprague-Dawley rats (200-250 g) were exposed 30 min/day for 4 days to thermogenic levels (rectal temperature increase of 2.2 degrees C) of microwave radiation [2.45 GHz, 80 mW/cm 2 , continuous-wave mode (CW)] or to a radiant heat source resulting in an equivalent increase in body temperature of 2.2 degrees C. On the fifth day the animals were sacrificed and their livers removed. The canalicular membranes were isolated and evaluated for adenosinetriphosphatase (ATPase) activity, total fatty acid composition and membrane fluidity characteristics. Mg ++ -ATPase activity (V max ) decreased by 48.5% in the group exposed to microwave radiation, with no significant change in the group exposed to radiant heat. The decrease in Mg ++ -ATPase was partially compensated by a concomitant increase in Na + /K + -ATPase activity (170% increase in V max over control) in animals exposed to microwave radiation, while no change occurred in the group exposed to radiant heat. This alteration in ATPase activity in the group exposed to microwave radiation is associated with a large decrease in the ratio of saturated to unsaturated fatty acids. Conversely, the group exposed to radiant heat had an increase in the ratio of saturated to unsaturated fatty acids. The most dramatic changes were found in the levels of arachidonic acid. Finally, the electron paramagnetic resonance (EPR) spin label technique used to measure the fluidity of the canalicular membranes of the animals in the three groups (sham, microwave radiation and radiant heat) indicated that the results were different in the three groups, reflecting the changes found in their fatty acid composition. The physiological response to open-quotes equivalentclose quotes thermal loads in rats is expressed differently for different types of energy sources. Possible mechanisms producing these divergent thermogenic responses are discussed. 34 refs., 3 figs., 2 tabs

Effect of Set-point Variation on Thermal Comfort and Energy Use in a Plus-energy Dwelling

DEFF Research Database (Denmark)

Toftum, Jørn; Kazanci, Ongun Berk; Olesen, Bjarne W.

2016-01-01

When designing buildings and space conditioning systems, the occupant thermal comfort, health, and productivity are the main criteria to satisfy. However, this should be achieved with the most energy-efficient space conditioning systems (heating, cooling, and ventilation). Control strategy, set......-points, and control dead-bands have a direct effect on the thermal environment in and the energy use of a building. The thermal environment in and the energy use of a building are associated with the thermal mass of the building and the control strategy, including set-points and control dead-bands. With thermally...... active building systems (TABS), temperatures are allowed to drift within the comfort zone, while in spaces with air-conditioning, temperatures in a narrower interval typically are aimed at. This behavior of radiant systems provides certain advantages regarding energy use, since the temperatures...

Epigenetics as a First Exit Problem

Science.gov (United States)

Aurell, E.; Sneppen, K.

2002-01-01

We develop a framework to discuss the stability of epigenetic states as first exit problems in dynamical systems with noise. We consider in particular the stability of the lysogenic state of the λ prophage. The formalism defines a quantitative measure of robustness of inherited states.

Solar heating by radiant floor: Experimental results and emission reduction obtained with a micro photovoltaic–heat pump system

International Nuclear Information System (INIS)

Izquierdo, M.; Agustín-Camacho, P. de

2015-01-01

Highlights: • This work presents a PVT multicrystalline solar heating system for buildings. • The PV DC electricity generated was converted to AC to drive an air–water heat pump. • Experimental results obtained from December 1, 2012 to April 30, 2013 are detailed. • An environmental study is also presented. - Abstract: An experimental research with a solar photovoltaic thermal (PVT) micro grid feeding a reversible air–water, 6 kW heating capacity heat pump, has been carried out from December 2012 to April 2013. Its purpose is to heat a laboratory that is used as a house prototype for the study of heating/cooling systems. It was built in accordance with the 2013 Spanish CTE, and has an area of 35 m 2 divided into two internal rooms: one of them housing the storage system, the solar controller, the inverter and the control system; the other one is occupied by three people. Its main thermal characteristics are: UA = 125 W/°C and a maximum thermal load about 6.0 kW at the initial time. The PVT field consists of 12 modules, with a total area of 15.7 m 2 and useful area of 14 m 2 . Each module is composed of 48 polycrystalline silicon cells of 243.4 cm 2 , which with a nominal efficiency 14% can generate a power of 180 W, being the total nominal power installed 2.16 kW. The PV system stores electricity in 250 Ah batteries from where is converted from DC to AC through a 3.0 kW inverter that feeds the heat pump. This works supplying 840 l/h of hot water at 35–45 °C to the radiant floor. The data storing system is recording variables such as solar radiation; temperatures; input power to batteries; heat produced; heat transferred by the radiant floor; heat pump’s COP; isolated ratio; and solar fraction. The objective of this work is to present and discuss the experimental results and the emission reduction of CO 2 obtained during the period from 01/12/2012 to 30/04/2013, including the detailed results of two representative days of Madrid’s climate: 28

Evaluation of six TPS algorithms in computing entrance and exit doses

Science.gov (United States)

Metwaly, Mohamed; Glegg, Martin; Baggarley, Shaun P.; Elliott, Alex

2014-01-01

Entrance and exit doses are commonly measured in in vivo dosimetry for comparison with expected values, usually generated by the treatment planning system (TPS), to verify accuracy of treatment delivery. This report aims to evaluate the accuracy of six TPS algorithms in computing entrance and exit doses for a 6 MV beam. The algorithms tested were: pencil beam convolution (Eclipse PBC), analytical anisotropic algorithm (Eclipse AAA), AcurosXB (Eclipse AXB), FFT convolution (XiO Convolution), multigrid superposition (XiO Superposition), and Monte Carlo photon (Monaco MC). Measurements with ionization chamber (IC) and diode detector in water phantoms were used as a reference. Comparisons were done in terms of central axis point dose, 1D relative profiles, and 2D absolute gamma analysis. Entrance doses computed by all TPS algorithms agreed to within 2% of the measured values. Exit doses computed by XiO Convolution, XiO Superposition, Eclipse AXB, and Monaco MC agreed with the IC measured doses to within 2%‐3%. Meanwhile, Eclipse PBC and Eclipse AAA computed exit doses were higher than the IC measured doses by up to 5.3% and 4.8%, respectively. Both algorithms assume that full backscatter exists even at the exit level, leading to an overestimation of exit doses. Despite good agreements at the central axis for Eclipse AXB and Monaco MC, 1D relative comparisons showed profiles mismatched at depths beyond 11.5 cm. Overall, the 2D absolute gamma (3%/3 mm) pass rates were better for Monaco MC, while Eclipse AXB failed mostly at the outer 20% of the field area. The findings of this study serve as a useful baseline for the implementation of entrance and exit in vivo dosimetry in clinical departments utilizing any of these six common TPS algorithms for reference comparison. PACS numbers: 87.55.‐x, 87.55.D‐, 87.55.N‐, 87.53.Bn PMID:24892349

Micrometeorological simulations to predict the impacts of heat mitigation strategies on pedestrian thermal comfort in a Los Angeles neighborhood

Science.gov (United States)

Taleghani, Mohammad; Sailor, David; Ban-Weiss, George A.

2016-02-01

The urban heat island impacts the thermal comfort of pedestrians in cities. In this paper, the effects of four heat mitigation strategies on micrometeorology and the thermal comfort of pedestrians were simulated for a neighborhood in eastern Los Angeles County. The strategies investigated include solar reflective ‘cool roofs’, vegetative ‘green roofs’, solar reflective ‘cool pavements’, and increased street-level trees. A series of micrometeorological simulations for an extreme heat day were carried out assuming widespread adoption of each mitigation strategy. Comparing each simulation to the control simulation assuming current land cover for the neighborhood showed that additional street-trees and cool pavements reduced 1.5 m air temperature, while cool and green roofs mostly provided cooling at heights above pedestrian level. However, cool pavements increased reflected sunlight from the ground to pedestrians at a set of unshaded receptor locations. This reflected radiation intensified the mean radiant temperature and consequently increased physiological equivalent temperature (PET) by 2.2 °C during the day, reducing the thermal comfort of pedestrians. At another set of receptor locations that were on average 5 m from roadways and underneath preexisting tree cover, cool pavements caused significant reductions in surface air temperatures and small changes in mean radiant temperature during the day, leading to decreases in PET of 1.1 °C, and consequent improvements in thermal comfort. For improving thermal comfort of pedestrians during the afternoon in unshaded locations, adding street trees was found to be the most effective strategy. However, afternoon thermal comfort improvements in already shaded locations adjacent to streets were most significant for cool pavements. Green and cool roofs showed the lowest impact on the thermal comfort of pedestrians since they modify the energy balance at roof level, above the height of pedestrians.

Micrometeorological simulations to predict the impacts of heat mitigation strategies on pedestrian thermal comfort in a Los Angeles neighborhood

International Nuclear Information System (INIS)

Taleghani, Mohammad; Ban-Weiss, George A; Sailor, David

2016-01-01

The urban heat island impacts the thermal comfort of pedestrians in cities. In this paper, the effects of four heat mitigation strategies on micrometeorology and the thermal comfort of pedestrians were simulated for a neighborhood in eastern Los Angeles County. The strategies investigated include solar reflective ‘cool roofs’, vegetative ‘green roofs’, solar reflective ‘cool pavements’, and increased street-level trees. A series of micrometeorological simulations for an extreme heat day were carried out assuming widespread adoption of each mitigation strategy. Comparing each simulation to the control simulation assuming current land cover for the neighborhood showed that additional street-trees and cool pavements reduced 1.5 m air temperature, while cool and green roofs mostly provided cooling at heights above pedestrian level. However, cool pavements increased reflected sunlight from the ground to pedestrians at a set of unshaded receptor locations. This reflected radiation intensified the mean radiant temperature and consequently increased physiological equivalent temperature (PET) by 2.2 °C during the day, reducing the thermal comfort of pedestrians. At another set of receptor locations that were on average 5 m from roadways and underneath preexisting tree cover, cool pavements caused significant reductions in surface air temperatures and small changes in mean radiant temperature during the day, leading to decreases in PET of 1.1 °C, and consequent improvements in thermal comfort. For improving thermal comfort of pedestrians during the afternoon in unshaded locations, adding street trees was found to be the most effective strategy. However, afternoon thermal comfort improvements in already shaded locations adjacent to streets were most significant for cool pavements. Green and cool roofs showed the lowest impact on the thermal comfort of pedestrians since they modify the energy balance at roof level, above the height of pedestrians. (letter)

After exit: Academic achievement patterns of former English language learners.

Directory of Open Access Journals (Sweden)

Ester J. de Jong

2004-09-01

Full Text Available With few exceptions, accountability systems for programs for English language learners (ELLs have focused on the achievement patterns of ELLs who are still considered “limited English proficient” and program evaluations have been unable to answer the question whether ELLs actually catch up with English proficient peers after attending a bilingual or English as a Second Language (ESL program. Disaggregating data for former ELLs can therefore provide important information for long-term district and program accountability. The study was concerned with the achievement patterns in English language arts, Math, and Science of former ELLs who attended a bilingual and a English as a Second Language (ESL program. It also explored whether length of program participation and grade level exited played a significant role in predicting academic achievement patterns for these exited students. Results indicate that 4th grade students more closely paralleled non- ELL students’ achievement patterns than 8th grade students, particularly for the BE students. While length of program participation is not a significant predictor of former ELLs’ academic success, exit grade does emerge as an important variable to take into consideration in setting exit guidelines.

Drink Specials and the Intoxication Levels of Patrons Exiting College Bars

Science.gov (United States)

Thombs, Dennis L.; Dodd, Virginia; Porkorny, Steven B.; Omli, Morrow R.; O'Mara, Ryan; Webb, Monica C.; Lacaci, Diana M.; Werch, Chad

2008-01-01

Objectives: To determine whether drink specials independently increase patrons' risk of achieving a high level of intoxication upon exiting drinking establishments. Methods: In a campus community, data were collected from exiting patrons (N=291) via sidewalk interviews and breath tests on 6 nights of 2 consecutive semesters. Results: A…

14 CFR 135.129 - Exit seating.

Science.gov (United States)

2010-01-01

... emergency evacuation provided by the certificate holder in printed or graphic form or the ability to... accordance with this section. (d) Each certificate holder shall include on passenger information cards.... (e) Each certificate holder shall include on passenger information cards, at each exit seat— (1) In...

A Multi-Wavelength Thermal Infrared and Reflectance Scene Simulation Model

Science.gov (United States)

Ballard, J. R., Jr.; Smith, J. A.; Smith, David E. (Technical Monitor)

2002-01-01

Several theoretical calculations are presented and our approach discussed for simulating overall composite scene thermal infrared exitance and canopy bidirectional reflectance of a forest canopy. Calculations are performed for selected wavelength bands of the DOE Multispectral Thermal Imagery and comparisons with atmospherically corrected MTI imagery are underway. NASA EO-1 Hyperion observations also are available and the favorable comparison of our reflective model results with these data are reported elsewhere.

Door locking and exit security measures on acute psychiatric admission wards

NARCIS (Netherlands)

Nijman, H.L.I.; Bowers, L.; Haglund, K.; Muir-Cochrane, E.; Simpson, A.; Merwe, M. van der

2011-01-01

Locking the exit doors of psychiatric wards is believed to reduce the risk of patients absconding. The aims of the study were to investigate both the prevalence of door locking and other exit security measures on UK admission wards, as well as whether door locking appears to be effective in keeping

The Super-Radiant Mechanism and the Widths of Compound Nuclear States

International Nuclear Information System (INIS)

Auerbach, N

2012-01-01

In the introduction I will present the theory of the super-radiant mechanism as applied to various phenomena. I will then discuss the statistics of resonance widths in a many-body Fermi system with open decay channels. Depending on the strength of the coupling to the continuum such systems show deviations from the standard Porter-Thomas distribution. The deviations result from the process of increasing interaction of the intrinsic states through the common decay channels. In the limit of very strong coupling this leads to super-radiance. The results I will present are important for the understanding of recent experimental data concerning the width distribution of compound neutron resonances in nuclei.

Thermal comfort and ventilation effectiveness in an office room with radiant floor cooling and displacement ventilation

DEFF Research Database (Denmark)

Krajcik, Michal; Tomasi, Roberta; Simone, Angela

2016-01-01

conditions, varying the nominal air change rate from 4.5h-1 down to 1.5h-1. Contaminant removal and mean-age-of-air measurements were performed to characterize the ventilation effectiveness and air velocity; air and operative temperature profiles were measured, together with thermal manikin equivalent...... temperatures, to evaluate the thermal environment. The combined system was able to achieve good ventilation effectiveness close to a heat source, so that in the occupant's breathing zone the ventilation effectiveness was significantly better than for ideal mixing, even at a nominal air change rate as low as 1......% at the highest nominal air change rate of 4.5h-1, even for an occupant sitting 1 meter in front of the supply diffuser, the local thermal discomfort occasioned by the excessive vertical temperature differences gives chilled ceilings the advantage over chilled floors for use with displacement ventilation....

EXIT Chart Analysis of Binary Message-Passing Decoders

DEFF Research Database (Denmark)

Lechner, Gottfried; Pedersen, Troels; Kramer, Gerhard

2007-01-01

Binary message-passing decoders for LDPC codes are analyzed using EXIT charts. For the analysis, the variable node decoder performs all computations in the L-value domain. For the special case of a hard decision channel, this leads to the well know Gallager B algorithm, while the analysis can...... be extended to channels with larger output alphabets. By increasing the output alphabet from hard decisions to four symbols, a gain of more than 1.0 dB is achieved using optimized codes. For this code optimization, the mixing property of EXIT functions has to be modified to the case of binary message......-passing decoders....

Numerical analysis of diffuse ceiling ventilation and its integration with a radiant ceiling system

DEFF Research Database (Denmark)

Zhang, Chen; Heiselberg, Per Kvols; Chen, Qingyan

2017-01-01

A novel system combining diffuse ceiling ventilation and radiant ceiling was proposed recently, with the aim of providing energy efficient and comfort environment to office buildings. Designing of such a system is challenging because of complex interactions between the two subsystems and a large ......-uniformity air distribution and further led to the draught problem in the occupied zone. This system was recommended to apply in the small offices instead of large, open spaces....

Thermal Excitation System for Shearography (TESS)

Science.gov (United States)

Lansing, Matthew D.; Bullock, Michael W.

1996-01-01

One of the most convenient and effective methods of stressing a part or structure for shearographic evaluation is thermal excitation. This technique involves heating the part, often convectively with a heat gun, and then monitoring with a shearography device the deformation during cooling. For a composite specimen, unbonds, delaminations, inclusions, or matrix cracking will deform during cooling differently than other more structurally sound regions and thus will appear as anomalies in the deformation field. However, one of the difficulties that cause this inspection to be dependent on the operator experience is the conventional heating process. Fanning the part with a heat gun by hand introduces a wide range of variability from person to person and from one inspection to the next. The goal of this research effort was to conduct research in the methods of thermal excitation for shearography inspection. A computerized heating system was developed for inspection of 0.61 m (24 in.) square panels. The Thermal Excitation System for Shearography (TESS) provides radiant heating with continuous digital measurement of the surface temperature profile to ensure repeatability. The TESS device functions as an accessory to any electronic shearography device.

Predicting The Exit Time Of Employees In An Organization Using Statistical Model

Directory of Open Access Journals (Sweden)

Ahmed Al Kuwaiti

2015-08-01

Full Text Available Employees are considered as an asset to any organization and each organization provide a better and flexible working environment to retain its best and resourceful workforce. As such continuous efforts are being taken to avoid or extend the exitwithdrawal of employees from the organization. Human resource managers are facing a challenge to predict the exit time of employees and there is no precise model existing at present in the literature. This study has been conducted to predict the probability of exit of an employee in an organization using appropriate statistical model. Accordingly authors designed a model using Additive Weibull distribution to predict the expected exit time of employee in an organization. In addition a Shock model approach is also executed to check how well the Additive Weibull distribution suits in an organization. The analytical results showed that when the inter-arrival time increases the expected time for the employees to exit also increases. This study concluded that Additive Weibull distribution can be considered as an alternative in the place of Shock model approach to predict the exit time of employee in an organization.

14 CFR 121.585 - Exit seating.

Science.gov (United States)

2010-01-01

... section and related to emergency evacuation provided by the certificate holder in printed or graphic form... include on passenger information cards, presented in the language in which briefings and oral commands are... passenger information cards, at each exit seat— (1) In the primary language in which emergency commands are...

Aggregating job exit statuses of a plurality of compute nodes executing a parallel application

Science.gov (United States)

Aho, Michael E.; Attinella, John E.; Gooding, Thomas M.; Mundy, Michael B.

2015-07-21

Aggregating job exit statuses of a plurality of compute nodes executing a parallel application, including: identifying a subset of compute nodes in the parallel computer to execute the parallel application; selecting one compute node in the subset of compute nodes in the parallel computer as a job leader compute node; initiating execution of the parallel application on the subset of compute nodes; receiving an exit status from each compute node in the subset of compute nodes, where the exit status for each compute node includes information describing execution of some portion of the parallel application by the compute node; aggregating each exit status from each compute node in the subset of compute nodes; and sending an aggregated exit status for the subset of compute nodes in the parallel computer.

Comparison of exit time moment spectra for extrinsic metric balls

DEFF Research Database (Denmark)

Hurtado, Ana; Markvorsen, Steen; Palmer, Vicente

2012-01-01

We prove explicit upper and lower bounds for the $L^1$-moment spectra for the Brownian motion exit time from extrinsic metric balls of submanifolds $P^m$ in ambient Riemannian spaces $N^n$. We assume that $P$ and $N$ both have controlled radial curvatures (mean curvature and sectional curvature...... obtain new intrinsic comparison results for the exit time spectra for metric balls in the ambient manifolds $N^n$ themselves....

Methods of total spectral radiant flux realization at VNIIOFI

Science.gov (United States)

Ivashin, Evgeniy; Lalek, Jan; Rybczyński, Andrzej; Ogarev, Sergey; Khlevnoy, Boris; Dobroserdov, Dmitry; Sapritsky, Victor

2018-02-01

VNIIOFI carries out works on realization of independent methods for realization of the total spectral radiant flux (TSRF) of incoherent optical radiation sources - reference high-temperature blackbodies (BB), halogen lamps, and LED with quasi-Lambert spatial distribution of radiance. The paper describes three schemes for measuring facilities using photometers, spectroradiometers and computer-controlled high class goniometer. The paper describes different approaches for TSRF realization at the VNIIOFI National radiometric standard on the basis of high-temperature BB and LED sources, and gonio-spectroradiometer. Further, they are planned to be compared, and the use of fixed-point cells (in particular, based on the high-temperature δ(MoC)-C metal-carbon eutectic with a phase transition temperature of 2583 °C corresponding to the metrological optical “source-A”) as an option instead of the BB is considered in order to enhance calibration accuracy.

Formal procedures of the exit from a community for a university social media agency

OpenAIRE

Peleschyshyn, Andriy; Peleschyshyn, Oksana; Korzh, Roman

2016-01-01

The aim of the paper is to consider the process of exiting of a university from an online community. The importance of performing the task of exiting in a proper way is proved. Preconditions and risks of the process are investigated. All the stages of the suggested algorithm for exiting from online community are scrutinized.

Effects of radiant exposure and wavelength spectrum of light-curing units on chemical and physical properties of resin cements

Directory of Open Access Journals (Sweden)

Adriano Fonseca Lima

2016-11-01

Full Text Available Objectives In this study, we evaluated the influence of different radiant exposures provided by single-peak and polywave light-curing units (LCUs on the degree of conversion (DC and the mechanical properties of resin cements. Materials and Methods Six experimental groups were established for each cement (RelyX ARC, 3M ESPE; LuxaCore Dual, Ivoclar Vivadent; Variolink, DMG, according to the different radiant exposures (5, 10, and 20 J/cm2 and two LCUs (single-peak and polywave. The specimens were made (7 mm in length × 2 mm in width × 1 mm in height using silicone molds. After 24 hours of preparation, DC measurement was performed using Fourier transform infrared spectrometry. The same specimens were used for the evaluation of mechanical properties (flexural strength, FS; elastic modulus, E by a three-point bending test. Data were assessed for normality, after which two-way analysis of variance (ANOVA and post hoc Tukey's test were performed. Results No properties of the Variolink cement were influenced by any of the considered experimental conditions. In the case of the RelyX ARC cement, DC was higher when polywave LCU was used; FS and E were not influenced by the conditions evaluated. The LuxaCore cement showed greater sensitivity to the different protocols. Conclusions On the basis of these results, both the spectrum of light emitted and the radiant exposure used could affect the properties of resin cements. However, the influence was material-dependent.

Efficiency, Leverage and Exit: The Role of Information Asymmetry in Concentrated Industries

DEFF Research Database (Denmark)

Siyahhan, Baran

2011-01-01

This paper develops a real options model of imperfect competition with asymmetric information that analyzes firms’ exit decisions. Optimal exit decision is linked to firm characteristics such as financial leverage and efficiency. The model shows that informational asymmetries can lead more...

Efficiency, Leverage and Exit: The Role of Information Asymmetry in Concentrated Industries

DEFF Research Database (Denmark)

Siyahhan, Baran

This paper develops a real options model of imperfect competition with asymmetric information that analyzes firms’ exit decisions. Optimal exit decision is linked to firm characteristics such as financial leverage and efficiency. The model shows that informational asymmetries can lead more...

Total spectral distributions from Hawking radiation

Energy Technology Data Exchange (ETDEWEB)

Broda, Boguslaw [University of Lodz, Department of Theoretical Physics, Faculty of Physics and Applied Informatics, Lodz (Poland)

2017-11-15

Taking into account the time dependence of the Hawking temperature and finite evaporation time of the black hole, the total spectral distributions of the radiant energy and of the number of particles have been explicitly calculated and compared to their temporary (initial) blackbody counterparts (spectral exitances). (orig.)

[Evaluation of thermal comfort in a student population: predictive value of an integrated index (Fanger's predicted mean value].

Science.gov (United States)

Catenacci, G; Terzi, R; Marcaletti, G; Tringali, S

1989-01-01

Practical applications and predictive values of a thermal comfort index (Fanger's PRV) were verified on a sample school population (1236 subjects) by studying the relationships between thermal sensations (subjective analysis), determined by means of an individual questionnaire, and the values of thermal comfort index (objective analysis) obtained by calculating the PMV index individually in the subjects under study. In homogeneous conditions of metabolic expenditure rate and thermal impedence from clothing, significant differences were found between the two kinds of analyses. At 22 degrees C mean radiant and operative temperature, the PMV values averaged 0 and the percentage of subjects who experienced thermal comfort did not exceed 60%. The high level of subjects who were dissatisfied with their environmental thermal conditions confirms the doubts regarding the use of the PMV index as a predictive indicator of thermal comfort, especially considering that the negative answers were not homogeneous nor attributable to the small thermal fluctuations (less than 0.5 degree C) measured in the classrooms.

Toward 3D structural information from quantitative electron exit wave analysis

International Nuclear Information System (INIS)

Borisenko, Konstantin B; Moldovan, Grigore; Kirkland, Angus I; Wang, Amy; Van Dyck, Dirk; Chen, Fu-Rong

2012-01-01

Simulations show that using a new direct imaging detector and accurate exit wave restoration algorithms allows nearly quantitative restoration of electron exit wave phase, which can be regarded as only qualitative for conventional indirect imaging cameras. This opens up a possibility of extracting accurate information on 3D atomic structure of the sample even from a single projection.

Thermo-active building systems and sound absorbers: Thermal comfort under real operation conditions

DEFF Research Database (Denmark)

Köhler, Benjamin; Rage, Nils; Chigot, Pierre

2018-01-01

Radiant systems are established today and have a high ecological potential in buildings while ensuring thermal comfort. Free-hanging sound absorbers are commonly used for room acoustic control, but can reduce the heat exchange when suspended under an active slab. The aim of this study...... is to evaluate the impact on thermal comfort of horizontal and vertical free-hanging porous sound absorbers placed in rooms of a building cooled by Thermo-Active Building System (TABS), under real operation conditions. A design comparing five different ceiling coverage ratios and two room types has been...... implemented during three measurement periods. A clear correlation between increase of ceiling coverage ratio and reduction of thermal comfort could not be derived systematically for each measurement period and room type, contrarily to what was expected from literature. In the first two monitoring periods...

Effect of radiant heat at the birth site in farrowing crates on hypothermia and behaviour in neonatal piglets

DEFF Research Database (Denmark)

Andersen, Heidi Mai-Lis; Pedersen, Lene Juul

2016-01-01

It has been documented that floor heating of the farrowing area in loose housed sows improves survival of piglets significantly. However, today, the majority of farrowing pens are designed with crating of sows and slatted floor at the birth site. The aim of this study was to investigate whether...... providing radiant heat at the birth site to new-born piglets in pens with crated sows reduced hypothermia, time to first milk intake and growth of the piglets during the 1st week. Second parity Danish Landrace×Yorkshire sows (n=36) were randomly divided into two groups: Control (CG) and heat (HG......). In the area behind the sow (zone 1), two radiant heat panels were mounted above the slatted floor in the HG. The farrowings were attended, and the heaters were turned on at birth of first piglet and turned off 12 h after. Birth time, time to leave zone 1, time to first contact with udder and time to first...

Association Between Health Plan Exit From Medicaid Managed Care and Quality of Care, 2006-2014.

Science.gov (United States)

Ndumele, Chima D; Schpero, William L; Schlesinger, Mark J; Trivedi, Amal N

2017-06-27

State Medicaid programs have increasingly contracted with insurers to provide medical care services for enrollees (Medicaid managed care plans). Insurers that provide these plans can exit Medicaid programs each year, with unclear effects on quality of care and health care experiences. To determine the frequency and interstate variation of health plan exit from Medicaid managed care and evaluate the relationship between health plan exit and market-level quality. Retrospective cohort of all comprehensive Medicaid managed care plans (N = 390) during the interval 2006-2014. Plan exit, defined as the withdrawal of a managed care plan from a state's Medicaid program. Eight measures from the Healthcare Effectiveness Data and Information Set were used to construct 3 composite indicators of quality (preventive care, chronic disease care management, and maternity care). Four measures from the Consumer Assessment of Healthcare Providers and Systems were combined into a composite indicator of patient experience, reflecting the proportion of beneficiaries rating experiences as 8 or above on a 0-to-10-point scale. Outcome data were available for 248 plans (68% of plans operating prior to 2014, representing 78% of beneficiaries). Of the 366 comprehensive Medicaid managed care plans operating prior to 2014, 106 exited Medicaid. These exiting plans enrolled 4 848 310 Medicaid beneficiaries, with a mean of 606 039 beneficiaries affected by plan exits annually. Six states had a mean of greater than 10% of Medicaid managed care recipients enrolled in plans that exited, whereas 10 states experienced no plan exits. Plans that exited from a state's Medicaid market performed significantly worse prior to exiting than those that remained in terms of preventive care (57.5% vs 60.4%; difference, 2.9% [95% CI, 0.3% to 5.5%]), maternity care (69.7% vs 73.6%; difference, 3.8% [95% CI, 1.7% to 6.0%]), and patient experience (73.5% vs 74.8%; difference, 1.3% [95% CI, 0.6% to 1

Stor forskel på kommuners bande-exit

DEFF Research Database (Denmark)

Mørck, Line Lerche

2015-01-01

DEBAT: Kommunerne har meget forskellige exit-tilbud til bande- og rockermedlemmer. Der er brug for mere indgående forskning, så vi ved, hvad der virker bedst, skriver Line Lerche Mørck, lektor i pædagogisk psykologi....

14 CFR 23.805 - Flightcrew emergency exits.

Science.gov (United States)

2010-01-01

... emergency exit must be located to allow rapid evacuation of the crew and have a size and shape of at least a... than six feet from the ground, an assisting means must be provided. The assisting means may be a rope...

Exit Polling in an Emergent Democracy: The Complex Case of Ukraine

Directory of Open Access Journals (Sweden)

Natalya Nikolaevna Kharchenko

2010-05-01

Full Text Available This report considers the methodological specifics of conducting exit polls to verify election returns, mainly using an example of election campaigns in Ukraine from 2002-2007. The deepest public resonance was aroused by exit polls conducted after the second round of Ukrainian presidential elections in 2004. These polls were one of the factors, which led to massive demonstrations (the so-called "Orange Revolution" and the revocation of election results. The authors show that in the environment of administrative pressure on voters, governmental control of mass media, and severe political struggle, inaccuracy increases. Thus, to acquire reliable and valid information, the polling methods used must be modified. The recommendations given for the methodology of conducting exit polls may be useful for emergent democratic countries.

Thermal conductivity of carbon foams. Measurements and interpretation; Conductivite thermique de mousses de carbone. Mesures et interpretation

Energy Technology Data Exchange (ETDEWEB)

Bourret, F.; Fort, C.; Duffa, G. [CEA CESTA, 33 - Le Barp (France)

1996-12-31

This paper describes thermal diffusivity measurements performed with the flash method on carbon foams with open porosity at ambient and higher temperatures. The influence of gas inclusions in the pores has been studied too. In this type of highly insulating material, radiant heat transfer plays a major role. The experiments carried out are interpreted in terms of equivalent thermal conductivity and show the difficulties encountered, in particular the dependence with sample thickness. An interpretation based on a direct simulation with an equivalent periodical material is given with an estimation of the gaseous conductivity based on the kinetics theory of gases. This study demonstrates that the notion of equivalent thermal conductivity is not applicable to all experiments. (J.S.) 10 refs.

Thermal comfort in Quebec City, Canada: sensitivity analysis of the UTCI and other popular thermal comfort indices in a mid-latitude continental city.

Science.gov (United States)

Provençal, Simon; Bergeron, Onil; Leduc, Richard; Barrette, Nathalie

2016-04-01

The newly developed Universal Thermal Climate Index (UTCI), along with the physiological equivalent temperature (PET), the humidex (HX) and the wind chill index (WC), was calculated in Quebec City, Canada, a city with a strong seasonal climatic variability, over a 1-year period. The objective of this study is twofold: evaluate the operational benefits of implementing the UTCI for a climate monitoring program of public comfort and health awareness as opposed to relying on traditional and simple indices, and determine whether thermal comfort monitoring specific to dense urban neighborhoods is necessary to adequately fulfill the goals of the program. In order to do so, an analysis is performed to evaluate each of these indices' sensitivity to the meteorological variables that regulate them in different environments. Overall, the UTCI was found to be slightly more sensitive to mean radiant temperature, moderately more sensitive to humidity and much more sensitive to wind speed than the PET. This dynamic changed slightly depending on the environment and the season. In hot weather, the PET was found to be more sensitive to mean radiant temperature and therefore reached high values that could potentially be hazardous more frequently than the UTCI and the HX. In turn, the UTCI's stronger sensitivity to wind speed makes it a superior index to identify potentially hazardous weather in winter compared to the PET and the WC. Adopting the UTCI broadly would be an improvement over the traditionally popular HX and WC indices. The urban environment produced favorable conditions to sustain heat stress conditions, where the indices reached high values more frequently there than in suburban locations, which advocates for weather monitoring specific to denser urban areas.

Thermal comfort in Quebec City, Canada: sensitivity analysis of the UTCI and other popular thermal comfort indices in a mid-latitude continental city

Science.gov (United States)

Provençal, Simon; Bergeron, Onil; Leduc, Richard; Barrette, Nathalie

2016-04-01

The newly developed Universal Thermal Climate Index (UTCI), along with the physiological equivalent temperature (PET), the humidex (HX) and the wind chill index (WC), was calculated in Quebec City, Canada, a city with a strong seasonal climatic variability, over a 1-year period. The objective of this study is twofold: evaluate the operational benefits of implementing the UTCI for a climate monitoring program of public comfort and health awareness as opposed to relying on traditional and simple indices, and determine whether thermal comfort monitoring specific to dense urban neighborhoods is necessary to adequately fulfill the goals of the program. In order to do so, an analysis is performed to evaluate each of these indices' sensitivity to the meteorological variables that regulate them in different environments. Overall, the UTCI was found to be slightly more sensitive to mean radiant temperature, moderately more sensitive to humidity and much more sensitive to wind speed than the PET. This dynamic changed slightly depending on the environment and the season. In hot weather, the PET was found to be more sensitive to mean radiant temperature and therefore reached high values that could potentially be hazardous more frequently than the UTCI and the HX. In turn, the UTCI's stronger sensitivity to wind speed makes it a superior index to identify potentially hazardous weather in winter compared to the PET and the WC. Adopting the UTCI broadly would be an improvement over the traditionally popular HX and WC indices. The urban environment produced favorable conditions to sustain heat stress conditions, where the indices reached high values more frequently there than in suburban locations, which advocates for weather monitoring specific to denser urban areas.

A Diversity Exit Interview/Survey for the Military

National Research Council Canada - National Science Library

Knouse, Stephen

2001-01-01

The exit interview and survey are means for identifying organizational problems, including diversity issues, through individuals separating from the organization, who are in a unique position to supply candid feedback...

Symmetry associated with symmetry break: Revisiting ants and humans escaping from multiple-exit rooms

Science.gov (United States)

Ji, Q.; Xin, C.; Tang, S. X.; Huang, J. P.

2018-02-01

Crowd panic has incurred massive injuries or deaths throughout the world, and thus understanding it is particularly important. It is now a common knowledge that crowd panic induces "symmetry break" in which some exits are jammed while others are underutilized. Amazingly, here we show, by experiment, simulation and theory, that a class of symmetry patterns come to appear for ants and humans escaping from multiple-exit rooms while the symmetry break exists. Our symmetry pattern is described by the fact that the ratio between the ensemble-averaging numbers of ants or humans escaping from different exits is equal to the ratio between the widths of the exits. The mechanism lies in the effect of heterogeneous preferences of agents with limited information for achieving the Nash equilibrium. This work offers new insights into how to improve public safety because large public areas are always equipped with multiple exits, and it also brings an ensemble-averaging method for seeking symmetry associated with symmetry breaking.

Effects of blue diode laser (445 nm) and LED (430-480 nm) radiant heat treatments on dental glass ionomer restoratives

Science.gov (United States)

Dionysopoulos, Dimitrios; Tolidis, Kosmas; Strakas, Dimitrios; Gerasimou, Paris; Sfeikos, Thrasyvoulos; Gutknecht, Norbert

2018-02-01

The purpose of this in vitro study was to evaluate the effect of two radiant heat treatments on water sorption, solubility and surface roughness of three conventional glass ionomer cements by using a blue diode laser (445 nm) and a light emitting diode (LED) unit (430-480 nm). Thirty disk-shaped specimens were prepared for each tested GIC (Equia Fil, Ketac Universal Aplicap and Riva Self Cure). The experimental groups (n = 10) of the study were as follows: Group 1 was the control group, in Group 2 the specimens were irradiated for 60 s at the top surface using a LED light-curing unit and in Group 3 the specimens were irradiated for 60 s at the top surface using a blue light diode laser. Statistical analysis was performed using one-way ANOVA and Tukey post hoc tests at a level of significance of a = 0.05. Radiant heat treatments with both laser and LED devices significantly decreased water sorption and solubility (p tested GICs. Blue diode laser treatment was seemed to be more effective compared to LED treatment for some of the tested materials. There were no changes in surface roughness of the GICs after the treatments (p > 0.05). Among the tested materials there were differences in water sorption and solubility (p 0.05). The use of the blue diode laser for this radiant heat treatment was harmless for the surface of the tested GICs and may be advantageous for the longevity of their restorations.

Exits from Temporary Jobs in Europe: A Competing Risks Analysis

DEFF Research Database (Denmark)

D'Addio, Anna Christina; Rosholm, Michael

2005-01-01

We study transitions out of temporary jobs using the waves 1994-1999 of the European Community Household Panel applying a discrete time duration model. Specifically, we use a multinomial logitmodel distinguishing between exits into permanent employment and non-employment. Two different specificat......We study transitions out of temporary jobs using the waves 1994-1999 of the European Community Household Panel applying a discrete time duration model. Specifically, we use a multinomial logitmodel distinguishing between exits into permanent employment and non-employment. Two different...

Adolescents Exiting Homelessness over Two Years: The Risk Amplification and Abatement Model

Science.gov (United States)

Milburn, Norweeta G.; Rice, Eric; Rotheram-Borus, Mary Jane; Mallett, Shelley; Rosenthal, Doreen; Batterham, Phillip; May, Susanne J.; Witkin, Andrea; Duan, Naihua

2009-01-01

The Risk Amplification and Abatement Model (RAAM) demonstrates that negative contact with socializing agents amplify risk, while positive contact abates risk for homeless adolescents. To test this model, the likelihood of exiting homelessness and returning to familial housing at 2 years and stably exiting over time are examined with longitudinal…

Radiant{trademark} Liquid Radioisotope Intravascular Radiation Therapy System

Energy Technology Data Exchange (ETDEWEB)

Eigler, N.; Whiting, J.; Chernomorsky, A.; Jackson, J.; Knapp, F.F., Jr.; Litvack, F.

1998-01-16

RADIANT{trademark} is manufactured by United States Surgical Corporation, Vascular Therapies Division, (formerly Progressive Angioplasty Systems). The system comprises a liquid {beta}-radiation source, a shielded isolation/transfer device (ISAT), modified over-the-wire or rapid exchange delivery balloons, and accessory kits. The liquid {beta}-source is Rhenium-188 in the form of sodium perrhenate (NaReO{sub 4}), Rhenium-188 is primarily a {beta}-emitter with a physical half-life of 17.0 hours. The maximum energy of the {beta}-particles is 2.1 MeV. The source is produced daily in the nuclear pharmacy hot lab by eluting a Tungsten-188/Rhenium-188 generator manufactured by Oak Ridge National Laboratory (ORNL). Using anion exchange columns and Millipore filters the effluent is concentrated to approximately 100 mCi/ml, calibrated, and loaded into the (ISAT) which is subsequently transported to the cardiac catheterization laboratory. The delivery catheters are modified Champion{trademark} over-the-wire, and TNT{trademark} rapid exchange stent delivery balloons. These balloons have thickened polyethylene walls to augment puncture resistance; dual radio-opaque markers and specially configured connectors.

Transgenic C. elegans dauer larvae expressing hookworm phospho null DAF-16/FoxO exit dauer.

Directory of Open Access Journals (Sweden)

Verena Gelmedin

Full Text Available Parasitic hookworms and the free-living model nematode Caenorhabtidis elegans share a developmental arrested stage, called the dauer stage in C. elegans and the infective third-stage larva (L3 in hookworms. One of the key transcription factors that regulate entrance to and exit from developmental arrest is the forkhead transcription factor DAF-16/FoxO. During the dauer stage, DAF-16 is activated and localized in the nucleus. DAF-16 is negatively regulated by phosphorylation by the upstream kinase AKT, which causes DAF-16 to localize out of the nucleus and the worm to exit from dauer. DAF-16 is conserved in hookworms, and hypothesized to control recovery from L3 arrest during infection. Lacking reverse genetic techniques for use in hookworms, we used C. elegans complementation assays to investigate the function of Ancylostoma caninum DAF-16 during entrance and exit from L3 developmental arrest. We performed dauer switching assays and observed the restoration of the dauer phenotype when Ac-DAF-16 was expressed in temperature-sensitive dauer defective C. elegans daf-2(e1370;daf-16(mu86 mutants. AKT phosphorylation site mutants of Ac-DAF-16 were also able to restore the dauer phenotype, but surprisingly allowed dauer exit when temperatures were lowered. We used fluorescence microscopy to localize DAF-16 during dauer and exit from dauer in C. elegans DAF-16 mutant worms expressing Ac-DAF-16, and found that Ac-DAF-16 exited the nucleus during dauer exit. Surprisingly, Ac-DAF-16 with mutated AKT phosphorylation sites also exited the nucleus during dauer exit. Our results suggest that another mechanism may be involved in the regulation DAF-16 nuclear localization during recovery from developmental arrest.

Numerical investigation of steady-state thermal behavior of an infrared detector cryo chamber

Directory of Open Access Journals (Sweden)

Singhal Mayank

2017-01-01

Full Text Available An infrared (IR detector is simply a transducer of radiant energy, converting radiant energy into a measurable form. Since radiation does not rely on visible light, it offers the possibility of seeing in the dark or through obscured conditions, by detecting the IR energy emitted by objects. One of the prime applications of IR detector systems for military use is in target acquisition and tracking of projectile systems. The IR detectors also have great potential in commercial market. Typically, IR detectors perform best when cooled to cryogenic temperatures in the range of nearly 120 K. However, the necessity to operate in such cryogenic regimes makes the application of IR detectors extremely complex. Further, prior to proceeding on to a full blown transient thermal analysis it is worthwhile to perform a steady-state numerical analysis for ascertaining the effect of variation in viz., material, gas conduction coefficient, h, emissivity, ε, on the temperature profile along the cryo chamber length. This would enable understanding the interaction between the cryo chamber and its environment. Hence, the present work focuses on the development of steady-state numerical models for thermal analysis of IR cryo chamber using MATLAB. The numerical results show that gas conduction coefficient has marked influence on the temperature profile of the cryo chamber whereas the emissivity has a weak effect. The experimental validation of numerical results has also been presented.

Two-dimensional exit dosimetry using a liquid-filled electronic portal imaging device and a convolution model

International Nuclear Information System (INIS)

Boellaard, Ronald; Herk, Marcel van; Uiterwaal, Hans; Mijnheer, Ben

1997-01-01

Background and purpose: To determine the accuracy of two-dimensional exit dose measurements with an electronic portal imaging device, EPID, using a convolution model for a variety of clinically relevant situations. Materials and methods: Exit doses were derived from portal dose images, obtained with a liquid-filled EPID at distances of 50 cm or more behind the patient, by using a convolution model. The resulting on- and off-axis exit dose values were first compared with ionization chamber exit dose measurements for homogeneous and inhomogeneous phantoms in open and wedged 4,8 and 18 MV photon beams. The accuracy of the EPID exit dose measurements was then determined for a number of anthropomorphic phantoms (lung and larynx) irradiated under clinical conditions and for a few patients treated in an 8 MV beam. The latter results were compared with in vivo exit dose measurements using diodes. Results: The exit dose can be determined from portal images with an accuracy of 1.2% (1 SD) compared with ionization chamber measurements for open beams and homogeneous phantoms at all tested beam qualities. In the presence of wedges and for inhomogeneous phantoms the average relative accuracy slightly deteriorated to 1.7% (1 SD). For lung phantoms in a 4 MV beam a similar accuracy was obtained after refinement of our convolution model, which requires knowledge of the patient contour. Differences between diode and EPID exit dose measurements for an anthropomorphic lung phantom in an 8 MV beam were 2.5% at most, with an average agreement within 1% (1 SD). For larynx phantoms in a 4 MV beam exit doses obtained with an ionization chamber and EPID agreed within 1.5% (1 SD). Finally, exit doses in a few patients irradiated in an 8 MV beam could be determined with the EPID with an accuracy of 1.1% (1 SD) relative to exit dose measurements using diodes. Conclusions: Portal images, obtained with our EPID and analyzed with our convolution model, can be used to determine the exit dose

Explaining discrepancies in reproductive health indicators from population-based surveys and exit surveys: a case from Rwanda.

Science.gov (United States)

Meekers, D; Ogada, E A

2001-06-01

Reproductive health programmes often need exit surveys and population-based surveys for monitoring and evaluation. This study investigates why such studies produce discrepant estimates of condom use, sexual behaviour and condom brand knowledge, and discusses the implications for future use of exit surveys for programme monitoring. Logistic regression is used to explain differences between a household survey of 1295 persons and an exit survey among a random sample of 2550 consumers at retail outlets in RWANDA: Discrepancies in ever use of condoms and risky sexual behaviours are due to differences in socioeconomic status of the two samples. After controls, exit surveys at most outlet types have the same results as the household survey. Only exit surveys at bars, nightclubs and hotels yield significantly different estimates. However, the above-average knowledge of Prudence Plus condoms in the exit interviews is not attributable to socioeconomic or demographic variables, most likely because respondents have seen the product at the outlets. Information about condom use and sexual behaviour obtained from exit surveys appears as accurate as that obtained through household surveys. Nevertheless, exit surveys must be used cautiously. Because exit surveys may include wealthier and better-educated respondents, they are not representative of the general population. The composition of exit survey samples should be validated through existing household surveys. Comparisons across survey types are generally unadvisable, unless they control for sample differences. When generalizing to the population at large is not needed (e.g. for studies aimed at identifying the characteristics and behaviour of users of particular products or services), exit surveys can provide an appropriate alternative to household surveys.

EXPERIMENTAL INVESTIGATION OF THE CONVECTIVE HEAT TRANSFER IN A SPIRALLY COILED CORRUGATED TUBE WITH RADIANT HEATING

Directory of Open Access Journals (Sweden)

Milan Đorđević

2017-12-01

Full Text Available The Archimedean spiral coil made of a transversely corrugated tube was exposed to radiant heating in order to represent a heat absorber of the parabolic dish solar concentrator. The main advantage of the considered innovative design solution is a coupling effect of the two passive methods for heat transfer enhancement - coiling of the flow channel and changes in surface roughness. The curvature ratio of the spiral coil varies from 0.029 to 0.234, while water and a mixture of propylene glycol and water are used as heat transfer fluids. The unique focus of this study is on specific boundary conditions since the heat flux upon the tube external surfaces varies not only in the circumferential direction, but in the axial direction as well. Instrumentation of the laboratory model of the heat absorber mounted in the radiation field includes measurement of inlet fluid flow rate, pressure drop, inlet and outlet fluid temperature and 35 type K thermocouples welded to the coil surface. A thermal analysis of the experimentally obtained data implies taking into consideration the externally applied radiation field, convective and radiative heat losses, conduction through the tube wall and convection to the internal fluid. The experimental results have shown significant enhancement of the heat transfer rate compared to spirally coiled smooth tubes, up to 240% in the turbulent flow regime.

Charting thermal emission variability at Pele, Janus Patera and Kanehekili Fluctus with the Galileo NIMS Io Thermal Emission Database (NITED)

Science.gov (United States)

Davies, Ashley Gerard; Veeder, Glenn J.; Matson, Dennis L.; Johnson, Torrence V.

2012-09-01

Using the NIMS Io Thermal Emission Database (NITED), a collection of over 1000 measurements of radiant flux from Io’s volcanoes (Davies, A.G. et al. [2012]. Geophys. Res. Lett. 39, L01201. doi:10.1029/2011GL049999), we have examined the variability of thermal emission from three of Io’s volcanoes: Pele, Janus Patera and Kanehekili Fluctus. At Pele, the 5-μm thermal emission as derived from 28 night time observations is remarkably steady at 37 ± 10 GW μm-1, re-affirming previous analyses that suggested that Pele an active, rapidly overturning silicate lava lake. Janus Patera also exhibits relatively steady 5-μm thermal emission (≈20 ± 3 GW μm-1) in the four observations where Janus is resolved from nearby Kanehekili Fluctus. Janus Patera might contain a Pele-like lava lake with an effusion rate (QF) of ≈40-70 m3 s-1. It should be a prime target for a future mission to Io in order to obtain data to determine lava eruption temperature. Kanehekili Fluctus has a thermal emission spectrum that is indicative of the emplacement of lava flows with insulated crusts. Effusion rate at Kanehekili Fluctus dropped by an order of magnitude from ≈95 m3 s-1 in mid-1997 to ≈4 m3 s-1 in late 2001.

Experimental investigation and feasibility analysis on a capillary radiant heating system based on solar and air source heat pump dual heat source

International Nuclear Information System (INIS)

Zhao, M.; Gu, Z.L.; Kang, W.B.; Liu, X.; Zhang, L.Y.; Jin, L.W.; Zhang, Q.L.

2017-01-01

Graphical abstract: (a) Vertical temperature gradient in Case 3, (b) PMV and PPD of the test room in Case 3, (c) operating time of SPCTS and ASHP systems in Case 3 and (d) the proportion of SPCTS operating time. - Highlights: • A capillary heating system based on solar and air source heat pump was developed. • Influence of supply water temperature on solar energy saving rate was investigated. • Heating performance and thermal comfort of capillary heating system were analyzed. • Low temperature heating with capillary is suitable for solar heating system. - Abstract: Due to sustainable development, solar energy has drawn much attention and been widely applied in buildings. However, the application of solar energy is limited because of its instability, intermittency and low energy density in winter. In order to use low density and instable solar energy source for heating and improve the utilization efficiency of solar energy, a solar phase change thermal storage (SPCTS) heating system using a radiant-capillary-terminal (RCT) to effectively match the low temperature hot water, a phase change thermal storage (PCTS) to store and continuously utilize the solar energy, and an air source heat pump (ASHP) as an alternate energy, was proposed and set up in this research. Series of experiments were conducted to obtain the relation between the solar radiation utilization rate and the heating supply temperatures, and to evaluate the performance of the RCT module and the indoor thermal environment of the system for its practical application in a residential building in the north-western City of Xi’an, China. The results show that energy saving of the solar heating system can be significantly improved by reducing the supplied water temperature, and the supplied water temperature of the RCT would be no more than 35 °C. The capillary radiation heating can adopt a lower water temperature and create a good thermal comfort environment as well. These results may lead to the

Ethnic variations in immigrant poverty exit and female employment: the missing link.

Science.gov (United States)

Kaida, Lisa

2015-04-01

Despite widespread interest in poverty among recent immigrants and female immigrant employment, research on the link between the two is limited. This study evaluates the effect of recently arrived immigrant women's employment on the exit from family poverty and considers the implications for ethnic differences in poverty exit. It uses the bivariate probit model and the Fairlie decomposition technique to analyze data from the Longitudinal Survey of Immigrants to Canada (LSIC), a nationally representative survey of immigrants arriving in Canada, 2000-2001. Results show that the employment of recently arrived immigrant women makes a notable contribution to lifting families out of poverty. Moreover, the wide ethnic variations in the probability of exit from poverty between European and non-European groups are partially explained by the lower employment rates among non-European women. The results suggest that the equal earner/female breadwinner model applies to low-income recent immigrant families in general, but the male breadwinner model explains the low probability of poverty exit among select non-European groups whose female employment rates are notably low.

Radiant recuperator modelling and design

Directory of Open Access Journals (Sweden)

Knežević Suzana D.

2017-01-01

Full Text Available Recuperators are frequently used in glass production and metallurgical processes to preheat combustion air by heat exchange with high temperature flue gases. Mass and energy balances of a 15 m high, concurrent radiant recuperator used in a glass fiber production process are given. The balances are used: for validation of a cell modeling method that predicts the performance of different recuperator designs, and for finding a simple solution to improve the existing recuperator. Three possible solutions are analyzed: to use the existing recuperator as a countercurrent one, to add an extra cylinder over the existing construction, and to make a system that consists of a central pipe and two concentric annular ducts. In the latter, two air streams flow in opposite directions, whereas air in the inner annular passage flows concurrently or countercurrently to flue gases. Compared with the concurrent recuperator, the countercurrent has only one drawback: the interface temperature is higher at the bottom. The advantages are: lower interface temperature at the top where the material is under maximal load, higher efficiency, and smaller pressure drop. Both concurrent and countercurrent double pipe-in-pipe systems are only slightly more efficient than pure concurrent and countercurrent recuperators, respectively. Their advantages are smaller interface temperatures whereas the disadvantages are their costs and pressure drops. To implement these solutions, the average velocities should be: for flue gas around 5 m/s, for air in the first passage less than 2 m/s, and for air in the second passage more than 25 m/s. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. EE 33027

Mean-Variance portfolio optimization when each asset has individual uncertain exit-time

Directory of Open Access Journals (Sweden)

Reza Keykhaei

2016-12-01

Full Text Available The standard Markowitz Mean-Variance optimization model is a single-period portfolio selection approach where the exit-time (or the time-horizon is deterministic. ‎In this paper we study the Mean-Variance portfolio selection problem ‎with ‎uncertain ‎exit-time ‎when ‎each ‎has ‎individual uncertain ‎xit-time‎, ‎which generalizes the Markowitz's model‎. ‎‎‎‎‎‎We provide some conditions under which the optimal portfolio of the generalized problem is independent of the exit-times distributions. Also, ‎‎it is shown that under some general circumstances, the sets of optimal portfolios‎ ‎in the generalized model and the standard model are the same‎.

Tunneling time, exit time and exit momentum in strong field tunnel ionization

International Nuclear Information System (INIS)

Teeny, Nicolas

2016-01-01

Tunnel ionization belongs to the fundamental processes of atomic physics. It is still an open question when does the electron tunnel ionize and how long is the duration of tunneling. In this work we solve the time-dependent Schroedinger equation in one and two dimensions and use ab initio quantum calculations in order to answer these questions. Additionally, we determine the exit momentum of the tunnel ionized electron from first principles. We find out results that are different from the assumptions of the commonly employed two-step model, which assumes that the electron ionizes at the instant of electric field maximum with a zero momentum. After determining the quantum final momentum distribution of tunnel ionized electrons we show that the two-step model fails to predict the correct final momentum. Accordingly we suggest how to correct the two-step model. Furthermore, we determine the instant at which tunnel ionization starts, which turns out to be different from the instant usually assumed. From determining the instant at which it is most probable for the electron to enter the tunneling barrier and the instant at which it exits we determine the most probable time spent under the barrier. Moreover, we apply a quantum clock approach in order to determine the duration of tunnel ionization. From the quantum clock we determine an average tunneling time which is different in magnitude and origin with respect to the most probable tunneling time. By defining a probability distribution of tunneling times using virtual detectors we relate both methods and explain the apparent discrepancy. The results found have in general an effect on the interpretation of experiments that measure the spectra of tunnel ionized electrons, and specifically on the calibration of the so called attoclock experiments, because models with imprecise assumptions are usually employed in order to interpret experimental results.

Tunneling time, exit time and exit momentum in strong field tunnel ionization

Energy Technology Data Exchange (ETDEWEB)

Teeny, Nicolas

2016-10-18

Tunnel ionization belongs to the fundamental processes of atomic physics. It is still an open question when does the electron tunnel ionize and how long is the duration of tunneling. In this work we solve the time-dependent Schroedinger equation in one and two dimensions and use ab initio quantum calculations in order to answer these questions. Additionally, we determine the exit momentum of the tunnel ionized electron from first principles. We find out results that are different from the assumptions of the commonly employed two-step model, which assumes that the electron ionizes at the instant of electric field maximum with a zero momentum. After determining the quantum final momentum distribution of tunnel ionized electrons we show that the two-step model fails to predict the correct final momentum. Accordingly we suggest how to correct the two-step model. Furthermore, we determine the instant at which tunnel ionization starts, which turns out to be different from the instant usually assumed. From determining the instant at which it is most probable for the electron to enter the tunneling barrier and the instant at which it exits we determine the most probable time spent under the barrier. Moreover, we apply a quantum clock approach in order to determine the duration of tunnel ionization. From the quantum clock we determine an average tunneling time which is different in magnitude and origin with respect to the most probable tunneling time. By defining a probability distribution of tunneling times using virtual detectors we relate both methods and explain the apparent discrepancy. The results found have in general an effect on the interpretation of experiments that measure the spectra of tunnel ionized electrons, and specifically on the calibration of the so called attoclock experiments, because models with imprecise assumptions are usually employed in order to interpret experimental results.

Results from radiant treatment in no Hodgkin's lymphomas of adults

International Nuclear Information System (INIS)

Alert, J.; Rodriguez, E.; Mesa, E.; Diaz, C.

1982-01-01

From 1973 to 1979, at the Institute of Oncology and Radiobiology, Havana City, 91 adults were irradiated because they underwent no Hodgkin's lymphomas at Stage I (located) and Stage II (regional extension) to whom radiant treatment was the basic therapeutic selection, with single or multiple fields and dose ranging between 3 500 and 4 000 rads-tumor, and some of them at Stage III, where primary treatment was chemotherapy. Present survival for all of them after 3 and 5 years is 55.7% and 54.7%, with 84.4% for patients at Stage I, 55.8% and 52.4% for Stage II and 33.8% for Stage III. Survival was similar for both sexes; in the same way ganglionar processes and those of extraganglionar localization presented no significant survival differences. Only to 7 patients (7.7%) modular forms were diagnosed. (author)

Experimental and raytrace results for throat-to-throat compound parabolic concentrators

Science.gov (United States)

Leviton, D. B.; Leitch, J. W.

1986-01-01

Compound parabolic concentrators are nonimaging cone-shaped optics with useful angular transmission characteristics. Two cones used throat-to-throat accept radiant flux within one well-defined acceptance angle and redistribute it into another. If the entrance cone is fed with Lambertian flux, the exit cone produces a beam whose half-angle is the exit cone's acceptance angle and whose cross section shows uniform irradiance from near the exit mouth to infinity. (The pair is a beam angle transformer). The design of one pair of cones is discussed, also an experiment to map the irradiance of the emergent beam, and a raytracing program which models the cones fed by Lambertian flux. Experimental results compare favorably with raytrace results.

Free of pollution gas - an utopia or attainable goal? Gas radiant burner with a small capacity

International Nuclear Information System (INIS)

Hofbauer, P.; Bornscheuer, W.

1993-01-01

The firm Viessmann has developed a gas radiant burner for boiler capacities up to 100 kN combusting gas with extremely low pollutant emissions. This is possible since from the reaction zone a considerable part of the combustion heat is delivered through radiation by means of a glowing special steel structure. The theoretical fundamentals are explained by means of considerations regarding the equilibrium and a reaction kinetic numerical model. (orig.) [de

Ecologies of ideologies : Explaining party entry and exit in European parliaments, 1945-2013

NARCIS (Netherlands)

van de Wardt, Marc; Berkhout, Joost; Vermeulen, Floris

This study introduces a population-ecological approach to the entry and exit of political parties. A primary proposition of population ecology is that organizational entry and exit depends on the number of organizations already present: that is, density. We propose that political parties mainly

Market entry and exit by biotech and device companies funded by venture capital.

Science.gov (United States)

Burns, Lawton R; Housman, Michael G; Robinson, Charles A

2009-01-01

Start-up companies in the biotechnology and medical device sectors are important sources of health care innovation. This paper describes the role of venture capital in supporting these companies and charts the growth in venture capital financial support. The paper then uses longitudinal data to describe market entry and exit by these companies. Similar factors are associated with entry and exit in the two sectors. Entries and exits in one sector also appear to influence entry in the other. These findings have important implications for developing innovative technologies and ensuring competitive markets in the life sciences.

Molecular dynamics study on the thermal conductivity and thermal rectification in graphene with geometric variations of doped boron

Energy Technology Data Exchange (ETDEWEB)

Liang, Qi, E-mail: alfred_02030210@163.com; Wei, Yuan

2014-03-15

Thermal conductivity and thermal rectification of graphene with geometric variations have been investigated by using classical non-equilibrium molecular dynamics simulation, and analyzed theoretically the cause of the changes of thermal conductivity and thermal rectification. Two different structural models, triangular single-boron-doped graphene (SBDG) and parallel various-boron-doped graphene (VBDG), were considered. The results indicated that the thermal conductivities of two different models are about 54–63% lower than pristine graphene. And it was also found that the structure of parallel various-boron-doped graphene is inhibited more strongly on the heat transfer than that of triangular single-boron-doped graphene. The reduction in the thermal conductivities of two different models gradually decreases as the temperature rises. The thermal conductivities of triangular boron-doped graphene have a large difference in both directions, and the thermal rectification of this structure shows the downward trend with increasing temperature. However, the thermal conductivities of parallel various-boron-doped graphene are similar in both directions, and the thermal rectification effect is not obvious in this structure. The phenomenon of thermal rectification exits in SBDG. It implies that the SBDG might be a potential promising structure for thermal rectifier by controlling the boron-doped model.

Molecular dynamics study on the thermal conductivity and thermal rectification in graphene with geometric variations of doped boron

International Nuclear Information System (INIS)

Liang, Qi; Wei, Yuan

2014-01-01

Thermal conductivity and thermal rectification of graphene with geometric variations have been investigated by using classical non-equilibrium molecular dynamics simulation, and analyzed theoretically the cause of the changes of thermal conductivity and thermal rectification. Two different structural models, triangular single-boron-doped graphene (SBDG) and parallel various-boron-doped graphene (VBDG), were considered. The results indicated that the thermal conductivities of two different models are about 54–63% lower than pristine graphene. And it was also found that the structure of parallel various-boron-doped graphene is inhibited more strongly on the heat transfer than that of triangular single-boron-doped graphene. The reduction in the thermal conductivities of two different models gradually decreases as the temperature rises. The thermal conductivities of triangular boron-doped graphene have a large difference in both directions, and the thermal rectification of this structure shows the downward trend with increasing temperature. However, the thermal conductivities of parallel various-boron-doped graphene are similar in both directions, and the thermal rectification effect is not obvious in this structure. The phenomenon of thermal rectification exits in SBDG. It implies that the SBDG might be a potential promising structure for thermal rectifier by controlling the boron-doped model

Wives' Relative Wages, Husbands' Paid Work Hours, and Wives' Labor-Force Exit

Science.gov (United States)

Shafer, Emily Fitzgibbons

2011-01-01

Economic theories predict that women are more likely to exit the labor force if their partners' earnings are higher and if their own wage rate is lower. In this article, I use the National Longitudinal Survey of Youth (N = 2,254) and discrete-time event-history analysis to show that wives' relative wages are more predictive of their exit than are…

The effects of radiant cooling versus convective cooling on human eye tear film stability and blinking rate

DEFF Research Database (Denmark)

Nygaard, Linette; Uth, Simon C.; Bolashikov, Zhecho Dimitrov

2014-01-01

The effect of indoor temperature, radiant and convective cooling on tear film stability and eye blink frequency was examined. 24 human subjects were exposed to the non-uniform environment generated by localised chilled beam and a chilled ceiling combined with overhead mixing ventilation. The subj......The effect of indoor temperature, radiant and convective cooling on tear film stability and eye blink frequency was examined. 24 human subjects were exposed to the non-uniform environment generated by localised chilled beam and a chilled ceiling combined with overhead mixing ventilation....... The subjects participated in four two-hour experiments. The room air temperature was kept at 26 °C or 28 °C. Tear film samples were collected after 30 min of acclimatisation and at the end of the exposures. Eye blinking frequency was analysed for the first and last 15 min of each exposure. The tear film...... stability decreased as the temperature increased. The highest number of subjects with unchanged or improved tear film quality was observed with the localised chilled beam at 26 °C. A trend was found between subjects who reported eye irritation and had a bad tear film quality....

First exit times of harmonically trapped particles: a didactic review

International Nuclear Information System (INIS)

Grebenkov, Denis S

2015-01-01

We revise the classical problem of characterizing first exit times of a harmonically trapped particle whose motion is described by a one- or multidimensional Ornstein–Uhlenbeck process. We start by recalling the main derivation steps of a propagator using Langevin and Fokker–Planck equations. The mean exit time, the moment-generating function and the survival probability are then expressed through confluent hypergeometric functions and thoroughly analyzed. We also present a rapidly converging series representation of confluent hypergeometric functions that is particularly well suited for numerical computation of eigenvalues and eigenfunctions of the governing Fokker–Planck operator. We discuss several applications of first exit times, such as the detection of time intervals during which motor proteins exert a constant force onto a tracer in optical tweezers single-particle tracking experiments; adhesion bond dissociation under mechanical stress; characterization of active periods of trend-following and mean-reverting strategies in algorithmic trading on stock markets; relation to the distribution of first crossing times of a moving boundary by Brownian motion. Some extensions are described, including diffusion under quadratic double-well potential and anomalous diffusion. (topical review)

Inhibition of the mitotic exit network in response to damaged telomeres.

Directory of Open Access Journals (Sweden)

Mauricio Valerio-Santiago

Full Text Available When chromosomal DNA is damaged, progression through the cell cycle is halted to provide the cells with time to repair the genetic material before it is distributed between the mother and daughter cells. In Saccharomyces cerevisiae, this cell cycle arrest occurs at the G2/M transition. However, it is also necessary to restrain exit from mitosis by maintaining Bfa1-Bub2, the inhibitor of the Mitotic Exit Network (MEN, in an active state. While the role of Bfa1 and Bub2 in the inhibition of mitotic exit when the spindle is not properly aligned and the spindle position checkpoint is activated has been extensively studied, the mechanism by which these proteins prevent MEN function after DNA damage is still unclear. Here, we propose that the inhibition of the MEN is specifically required when telomeres are damaged but it is not necessary to face all types of chromosomal DNA damage, which is in agreement with previous data in mammals suggesting the existence of a putative telomere-specific DNA damage response that inhibits mitotic exit. Furthermore, we demonstrate that the mechanism of MEN inhibition when telomeres are damaged relies on the Rad53-dependent inhibition of Bfa1 phosphorylation by the Polo-like kinase Cdc5, establishing a new key role of this kinase in regulating cell cycle progression.

Visual Barriers to Prevent Ambulatory ALzheimer's Patients from Exiting through an Emergency Door.

Science.gov (United States)

Namazi, Kevan H.; And Others

1989-01-01

Conducted study on Alzheimer's unit to test seven different visual barrier conditions for reducing patient exits. Findings indicated that exiting was eliminated under two conditions. Results suggest visual agnosia, the inability to interpret what the eye sees, may be used as tool in managing wandering behavior of Alzheimer's patients. (Author/NB)

Entrance, exit, and reentrance of one shot with a shotgun

DEFF Research Database (Denmark)

Gulmann, C; Hougen, H P

1999-01-01

The case being reported is one of a homicidal shotgun fatality with an unusual wound pattern. A 34-year-old man was shot at close range with a 12-gauge shotgun armed with No. 5 birdshot ammunition. The shot entered the left axillary region, exited through the left infraclavicular region, and ther......The case being reported is one of a homicidal shotgun fatality with an unusual wound pattern. A 34-year-old man was shot at close range with a 12-gauge shotgun armed with No. 5 birdshot ammunition. The shot entered the left axillary region, exited through the left infraclavicular region...

Formation Mechanisms for Entry and Exit Defects in Bobbin Friction Stir Welding

Directory of Open Access Journals (Sweden)

Abbas Tamadon

2018-01-01

Full Text Available Bobbin friction stir welding (BFSW is an innovative variant for the solid state welding process whereby a rotating symmetrical tool causes a fully penetrated bond. Despite the process development, there are still unknown variables in the characterization of the process parameters which can cause uncontrolled weld defects. The entry zone and the exit zone consist of two discontinuity-defects and removing them is one of the current challenges for improving the weld quality. In the present research, the characteristic features of the entry and exit defects in the weld structure and formation mechanism of them during the BFSW processing was investigated. Using stacked layers of multi-colour plasticine the material flow, analogous to metal flow, can be visualised. By using different colours as the path markers of the analogue model, the streamline flow can be easily delineated in the discontinuity defects compared with the metal welds. AA6082-T6 aluminium plates and multi-layered plasticine slabs were employed to replicate the entry-exit defects in the metal weld and analogue samples. The fixed-bobbin tool utilized for this research was optimized by adding a thread feature and tri-flat geometry to the pin and closed-end spiral scrolls on both shoulder surfaces. Samples were processed at different rotating and longitudinal speeds to show the degree of dependency on the welding parameters for the defects. The analogue models showed that the entry zone and the exit zone of the BFSW are affected by the inhomogeneity of the material flow regime which causes the ejection or disruption of the plastic flow in the gap between the bobbin shoulders. The trial aluminium welds showed that the elimination of entry-exit defects in the weld body is not completely possible but the size of the defects can be minimized by modification of the welding parameters. For the entry zone, the flow pattern evolution suggested formation mechanisms for a sprayed tail, island zone

A method of exploration of the atmosphere of Titan. [hot air balloon heated by solar radiation or planetary thermal flux

Science.gov (United States)

Blamont, J.

1978-01-01

A hot-air balloon, with the air heated by natural sources, is described. Buoyancy is accomplished by either solar heating or by utilizing the IR thermal flux of the planet to heat the gas in the balloon. Altitude control is provided by a valve which is opened and closed by a barometer. The balloon is made of an organic material which has to absorb radiant energy and to emit as little as possible.

Hybrid heating systems optimization of residential environment to have thermal comfort conditions by numerical simulation.

Science.gov (United States)

Jahantigh, Nabi; Keshavarz, Ali; Mirzaei, Masoud

2015-01-01

The aim of this study is to determine optimum hybrid heating systems parameters, such as temperature, surface area of a radiant heater and vent area to have thermal comfort conditions. DOE, Factorial design method is used to determine the optimum values for input parameters. A 3D model of a virtual standing thermal manikin with real dimensions is considered in this study. Continuity, momentum, energy, species equations for turbulent flow and physiological equation for thermal comfort are numerically solved to study heat, moisture and flow field. K - ɛRNG Model is used for turbulence modeling and DO method is used for radiation effects. Numerical results have a good agreement with the experimental data reported in the literature. The effect of various combinations of inlet parameters on thermal comfort is considered. According to Pareto graph, some of these combinations that have significant effect on the thermal comfort require no more energy can be used as useful tools. A better symmetrical velocity distribution around the manikin is also presented in the hybrid system.

The impact of ill health on exit from paid employment in Europe among older workers.

Science.gov (United States)

van den Berg, Tilja; Schuring, Merel; Avendano, Mauricio; Mackenbach, Johan; Burdorf, Alex

2010-12-01

To determine the impact of ill health on exit from paid employment in Europe among older workers. Participants of the Survey on Health and Ageing in Europe (SHARE) in 11 European countries in 2004 and 2006 were selected when 50-63 years old and in paid employment at baseline (n=4611). Data were collected on self-rated health, chronic diseases, mobility limitations, obesity, smoking, alcohol use, physical activity and work characteristics. Participants were classified into employed, retired, unemployed and disabled at the end of the 2-year follow-up. Multinomial logistic regression was used to estimate the effect of different measures of ill health on exit from paid employment. During the 2-year follow-up, 17% of employed workers left paid employment, mainly because of early retirement. Controlling for individual and work related characteristics, poor self-perceived health was strongly associated with exit from paid employment due to retirement, unemployment or disability (ORs from 1.32 to 4.24). Adjustment for working conditions and lifestyle reduced the significant associations between ill health and exit from paid employment by 0-18.7%. Low education, obesity, low job control and effort-reward imbalance were associated with measures of ill health, but also risk factors for exit from paid employment after adjustment for ill health. Poor self-perceived health was strongly associated with exit from paid employment among European workers aged 50-63 years. This study suggests that the influence of ill health on exit from paid employment could be lessened by measures targeting obesity, problematic alcohol use, job control and effort-reward balance.

Thermal math model analysis of FRSI test article subjected to cold soak and entry environments. [Flexible Reuseable Surface Insulation in Space Shuttle Orbiter

Science.gov (United States)

Gallegos, J. J.

1978-01-01

A multi-objective test program was conducted at the NASA/JSC Radiant Heat Test Facility in which an aluminum skin/stringer test panel insulated with FRSI (Flexible Reusable Surface Insulation) was subjected to 24 simulated Space Shuttle Orbiter ascent/entry heating cycles with a cold soak in between in the 10th and 20th cycles. A two-dimensional thermal math model was developed and utilized to predict the thermal performance of the FRSI. Results are presented which indicate that the modeling techniques and property values have been proven adequate in predicting peak structure temperatures and entry thermal responses from both an ambient and cold soak condition of an FRSI covered aluminum structure.

Thermal equilibrium of goats.

Science.gov (United States)

Maia, Alex S C; Nascimento, Sheila T; Nascimento, Carolina C N; Gebremedhin, Kifle G

2016-05-01

The effects of air temperature and relative humidity on thermal equilibrium of goats in a tropical region was evaluated. Nine non-pregnant Anglo Nubian nanny goats were used in the study. An indirect calorimeter was designed and developed to measure oxygen consumption, carbon dioxide production, methane production and water vapour pressure of the air exhaled from goats. Physiological parameters: rectal temperature, skin temperature, hair-coat temperature, expired air temperature and respiratory rate and volume as well as environmental parameters: air temperature, relative humidity and mean radiant temperature were measured. The results show that respiratory and volume rates and latent heat loss did not change significantly for air temperature between 22 and 26°C. In this temperature range, metabolic heat was lost mainly by convection and long-wave radiation. For temperature greater than 30°C, the goats maintained thermal equilibrium mainly by evaporative heat loss. At the higher air temperature, the respiratory and ventilation rates as well as body temperatures were significantly elevated. It can be concluded that for Anglo Nubian goats, the upper limit of air temperature for comfort is around 26°C when the goats are protected from direct solar radiation. Copyright © 2016 Elsevier Ltd. All rights reserved.

49 CFR 238.113 - Emergency window exits.

Science.gov (United States)

2010-10-01

..., electrical locker, or kitchen); and (B) There are no more than eight seats in the seating area. (4) Cars with...), a bathroom, kitchen, or locomotive cab is not considered a “compartment.” (b) Ease of operability. On or after November 8, 1999, each emergency window exit shall be designed to permit rapid and easy...

Coupling of a discrete ordinate 3-D radiant heat transfer model with the PHOENICS fluid mechanics software; Couplage d`un modele radiatif tridimensionnel aux ordonnees discretes au logiciel de mecanique des fluides phoenics

Energy Technology Data Exchange (ETDEWEB)

Muller, J [IRSID, Institut de Recherches Siderurgie, 57 - Maizieres-les-Metz (France)

1997-12-31

Radiant heat transfer is the main solution retained in many iron and steel metallurgy installations (re-heating and annealing furnaces etc..). Today, it has become important to dispose of performing radiant heat transfer models in heat transfer and fluid mechanics simulation softwares, and well adapted to multidimensional industrial problems. This work presents the discrete ordinate radiant heat transfer model developed at the IRSID (the French institute of research in iron and steel metallurgy) and coupled with the PHOENICS heat transfer-fluid mechanics software. Three modeling approaches are presented concerning the radiative properties of gases (H{sub 2}O-CO{sub 2}). A ``weighted grey gases sum`` model gives satisfactory results for several 1-D validation cases. (J.S.) 20 refs.

Coupling of a discrete ordinate 3-D radiant heat transfer model with the PHOENICS fluid mechanics software; Couplage d`un modele radiatif tridimensionnel aux ordonnees discretes au logiciel de mecanique des fluides phoenics

Energy Technology Data Exchange (ETDEWEB)

Muller, J. [IRSID, Institut de Recherches Siderurgie, 57 - Maizieres-les-Metz (France)

1996-12-31

Radiant heat transfer is the main solution retained in many iron and steel metallurgy installations (re-heating and annealing furnaces etc..). Today, it has become important to dispose of performing radiant heat transfer models in heat transfer and fluid mechanics simulation softwares, and well adapted to multidimensional industrial problems. This work presents the discrete ordinate radiant heat transfer model developed at the IRSID (the French institute of research in iron and steel metallurgy) and coupled with the PHOENICS heat transfer-fluid mechanics software. Three modeling approaches are presented concerning the radiative properties of gases (H{sub 2}O-CO{sub 2}). A ``weighted grey gases sum`` model gives satisfactory results for several 1-D validation cases. (J.S.) 20 refs.

NAD+ Is a Food Component That Promotes Exit from Dauer Diapause in Caenorhabditis elegans.

Directory of Open Access Journals (Sweden)

Mykola Mylenko

Full Text Available The free-living soil nematode Caenorhabditis elegans adapts its development to the availability of food. When food is scarce and population density is high, worms enter a developmentally arrested non-feeding diapause stage specialized for long-term survival called the dauer larva. When food becomes available, they exit from the dauer stage, resume growth and reproduction. It has been postulated that compound(s present in food, referred to as the "food signal", promote exit from the dauer stage. In this study, we have identified NAD+ as a component of bacterial extract that promotes dauer exit. NAD+, when dissolved in alkaline medium, causes opening of the mouth and ingestion of food. We also show that to initiate exit from the dauer stage in response to NAD+ worms require production of serotonin. Thus, C. elegans can use redox cofactors produced by dietary organisms to sense food.

Exit, voice, and loyalty in the Italian public health service: macroeconomic and corporate implications.

Science.gov (United States)

Ippolito, Adelaide; Impagliazzo, Cira; Zoccoli, Paola

2013-01-01

The paper analyses how customers of public health organizations can express their dissatisfaction for the services offered to them. The main aim is to evaluate the effects that possible dissatisfaction of Italian public health service customers can have on public health organizations. We adopted the methodological scheme developed by Hirschman with exit, voice, and loyalty, considering the macroeconomic and corporate implications that it causes for Italian public health organizations. The study investigated the effects developed by exit of the patients on the system of financing of local health authorities considering both the corporate level of analysis and the macroeconomic level. As a result, local health authority management is encouraged to pay greater attention to the exit phenomena through the adoption of tools that promote loyalty, such as the promotion of voice, even if exit is not promoting, at a macroeconomic level, considerable attention to this phenomenon.

Exit, Voice, and Loyalty in the Italian Public Health Service: Macroeconomic and Corporate Implications

Science.gov (United States)

Impagliazzo, Cira; Zoccoli, Paola

2013-01-01

The paper analyses how customers of public health organizations can express their dissatisfaction for the services offered to them. The main aim is to evaluate the effects that possible dissatisfaction of Italian public health service customers can have on public health organizations. We adopted the methodological scheme developed by Hirschman with exit, voice, and loyalty, considering the macroeconomic and corporate implications that it causes for Italian public health organizations. The study investigated the effects developed by exit of the patients on the system of financing of local health authorities considering both the corporate level of analysis and the macroeconomic level. As a result, local health authority management is encouraged to pay greater attention to the exit phenomena through the adoption of tools that promote loyalty, such as the promotion of voice, even if exit is not promoting, at a macroeconomic level, considerable attention to this phenomenon. PMID:24348148

Ecologies of Ideologies : Explaining Party Entry and Exit in West-European Parliaments, 1945-2013

NARCIS (Netherlands)

van de Wardt, M.; Berkhout, J.; Vermeulen, F.

2017-01-01

This study introduces a population-ecological approach to the entry and exit of political parties. A primary proposition of population ecology is that organizational entry and exit depends on the number of organizations already present: that is, density. We propose that political parties mainly

Sampling for Patient Exit Interviews: Assessment of Methods Using Mathematical Derivation and Computer Simulations.

Science.gov (United States)

Geldsetzer, Pascal; Fink, Günther; Vaikath, Maria; Bärnighausen, Till

2018-02-01

(1) To evaluate the operational efficiency of various sampling methods for patient exit interviews; (2) to discuss under what circumstances each method yields an unbiased sample; and (3) to propose a new, operationally efficient, and unbiased sampling method. Literature review, mathematical derivation, and Monte Carlo simulations. Our simulations show that in patient exit interviews it is most operationally efficient if the interviewer, after completing an interview, selects the next patient exiting the clinical consultation. We demonstrate mathematically that this method yields a biased sample: patients who spend a longer time with the clinician are overrepresented. This bias can be removed by selecting the next patient who enters, rather than exits, the consultation room. We show that this sampling method is operationally more efficient than alternative methods (systematic and simple random sampling) in most primary health care settings. Under the assumption that the order in which patients enter the consultation room is unrelated to the length of time spent with the clinician and the interviewer, selecting the next patient entering the consultation room tends to be the operationally most efficient unbiased sampling method for patient exit interviews. © 2016 The Authors. Health Services Research published by Wiley Periodicals, Inc. on behalf of Health Research and Educational Trust.

In-Therm Klimavæg

DEFF Research Database (Denmark)

Marcos Meson, Victor

2014-01-01

The report analyses the improvement possibilities for a prefabricated radiant wall panel, the report focuses on the possible modifications of the concrete mix in order to enhance the thermal properties of the radiant panel....

Pressure suppression pool hydrodynamic studies for horizontal vent exit of Indian PHWR containment

International Nuclear Information System (INIS)

Mohan, N.; Bajaj, S.S.; Saha, P.

1994-01-01

The standard Indian PHWR incorporates a pressure suppression type of containment system with a suppression pool.The design of KAPS (Kakrapar Atomic Power Station) suppression pool system adopts a modified system of downcomers having horizontal vents as compared to vertical vents of NAPS (Narora Atomic Power Station). Hydrodynamic studies for vertical vents have been reported earlier. This paper presents hydrodynamic studies for horizontal type vent system during LOCA. These studies include the phenomenon of vent clearing (where the water slug standing in downcomer initially is injected to wetwell due to rapid pressurization of drywell) followed by pool swell (elevation of pool water due to formation of bubbles due to air mass entering pool at the exit of horizontal vents from drywell). The analysis performed for vent clearing and pool swell is based on rigorous thermal hydraulic calculation consisting of conservation of air-steam mixture mass, momentum and thermal energy and mass of air. Horizontal vent of downcomer is modelled in such a way that during steam-air flow, variation of flow area due to oscillating water surface in downcomer could be considered. Calculation predicts that the vent gets cleared in about 1.0 second and the corresponding downward slug velocity in the downcomer is 4.61 m/sec. The maximum pool swell for a conservative lateral expansion is calculated to be 0.56 m. (author). 3 refs., 12 figs

The exit-time problem for a Markov jump process

Science.gov (United States)

Burch, N.; D'Elia, M.; Lehoucq, R. B.

2014-12-01

The purpose of this paper is to consider the exit-time problem for a finite-range Markov jump process, i.e, the distance the particle can jump is bounded independent of its location. Such jump diffusions are expedient models for anomalous transport exhibiting super-diffusion or nonstandard normal diffusion. We refer to the associated deterministic equation as a volume-constrained nonlocal diffusion equation. The volume constraint is the nonlocal analogue of a boundary condition necessary to demonstrate that the nonlocal diffusion equation is well-posed and is consistent with the jump process. A critical aspect of the analysis is a variational formulation and a recently developed nonlocal vector calculus. This calculus allows us to pose nonlocal backward and forward Kolmogorov equations, the former equation granting the various moments of the exit-time distribution.

Three dimensional modelling and numerical analysis of super-radiant harmonic emission in FEL (optical klystron)

International Nuclear Information System (INIS)

Gover, A.; Friedman, A.; Luccio, A.

1986-09-01

A full 3-D Analysis of super-radiant (bunched electron) free electron harmonic radiation is presented. A generalized form of the FEL pendulum equation was derived and numerically solved. Both spectral and phasor formulation were developed to treat the radiation in the time domain. In space the radiation field is expanded in terms of either a set of free space discrete modes or plane waves. The numerical solutions reveal some new distinctly 3-D effects to which we provide a physical explanation. 12 refs., 9 figs., 5 tabs

Experimental research on the indoor temperature and humidity fields in radiant ceiling air-conditioning system under natural ventilation

Science.gov (United States)

Huang, Tao; Xiang, Yutong; Wang, Yonghong

2017-05-01

In this paper, the indoor temperature and humidity fields of the air in a metal ceiling radiant panel air conditioning system with fresh air under natural ventilation were researched. The temperature and humidity distributions at different height and different position were compared. Through the computation analysis of partial pressure of water vapor, the self-recovery characteristics of humidity after the natural ventilation was discussed.

Probability evolution method for exit location distribution

Science.gov (United States)

Zhu, Jinjie; Chen, Zhen; Liu, Xianbin

2018-03-01

The exit problem in the framework of the large deviation theory has been a hot topic in the past few decades. The most probable escape path in the weak-noise limit has been clarified by the Freidlin-Wentzell action functional. However, noise in real physical systems cannot be arbitrarily small while noise with finite strength may induce nontrivial phenomena, such as noise-induced shift and noise-induced saddle-point avoidance. Traditional Monte Carlo simulation of noise-induced escape will take exponentially large time as noise approaches zero. The majority of the time is wasted on the uninteresting wandering around the attractors. In this paper, a new method is proposed to decrease the escape simulation time by an exponentially large factor by introducing a series of interfaces and by applying the reinjection on them. This method can be used to calculate the exit location distribution. It is verified by examining two classical examples and is compared with theoretical predictions. The results show that the method performs well for weak noise while may induce certain deviations for large noise. Finally, some possible ways to improve our method are discussed.

Histopathological detection of entry and exit holes in human skin wounds caused by firearms.

Science.gov (United States)

Baptista, Marcus Vinícius; d'Ávila, Solange C G P; d'Ávila, Antônio Miguel M P

2014-07-01

The judiciary needs forensic medicine to determine the difference between an entry hole and an exit hole in human skin caused by firearms for civilian use. This important information would be most useful if a practical and accurate method could be done with low-cost and minimal technological resources. Both macroscopic and microscopic analyses were performed on skin lesions caused by firearm projectiles, to establish histological features of 14 entry holes and 14 exit holes. Microscopically, in the abrasion area macroscopically observed, there were signs of burns (sub-epidermal cracks and keratinocyte necrosis) in the entrance holes in all cases. These signs were not found in three exit holes which showed an abrasion collar, nor in other exit holes. Some other microscopic features not found in every case were limited either to entry holes, such as cotton fibres, grease deposits, or tattooing in the dermis, or to exit holes, such as adipose tissue, bone or muscle tissue in the dermis. Coagulative necrosis of keratinocytes and sub-epidermal cracks are characteristic of entry holes. Despite the small sample size, it can be safely inferred that this is an important microscopic finding, among others less consistently found, to define an entry hole in questionable cases. Copyright © 2014 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Exit and Failure of Credit Unions in Brazil: A Risk Analysis

Directory of Open Access Journals (Sweden)

Flávio Leonel de Carvalho

2015-04-01

Full Text Available This study aims to investigate the factors that affect the market exit of Brazilian singular credit unions from 1995 to 2009; it also identifies and lists the determinants of various types of market exits and analyzes whether profitability is a significant factor for credit union survival. This study was conducted with accounting data provided by the Central Bank of Brazil, which derives only from individual cooperatives, i.e. singular credit unions. Quarterly financial statements from these credit unions that were active from 1995 to the second quarter of 2009 were employed, totaling 71,325 observations for 1,929 credit unions. Based on survival and the model of competing risks (such as the Cox, Exponential, Weibull, Gompertz, and Competing Risk models, the results show that there is no statistical evidence to ensure a correlation between profitability and credit union survival. The results also suggest that the size of credit unions plays a key role in their survival and longevity and that their funding and investment management are related to their survival and risk of market exit. In conclusion, the results confirm the initial idea that the duality inherent to credit unions - cooperative principles versus economic efficiency - might influence the stability, survival, and longevity of these institutions. Such results may also imply that a credit union embracing the rationale of a private bank will become more estranged from its members, something which will hinder its future operations and increase the likelihood of its exit from the market.

Thermal performance of capillary micro tubes integrated into the sandwich element made of concrete

DEFF Research Database (Denmark)

Mikeska, Tomas; Svendsen, Svend

2013-01-01

integrated into the thin plate of sandwich element made of HPC can supply the energy needed for heating and cooling. The investigations were conceived as a low temperature concept, where the difference between the temperature of circulating fluid and air in the room was kept in range of 1 to 4°C. © (2013......The thermal performance of radiant heating and cooling systems (RHCS) composed of capillary micro tubes (CMT) integrated into the inner plate of sandwich elements made of High Performance Concrete (HPC) was investigated in the article. Temperature distribution in HPC elements around integrated CMT...

Full Scale Measurements and CFD Investigations of a Wall Radiant Cooling System Based on Plastic Capillary Tubes in Thin Concrete Walls

DEFF Research Database (Denmark)

Mikeska, Tomás; Fan, Jianhua; Svendsen, Svend

2017-01-01

Densely occupied spaces such as classrooms can very often have problems with overheating. It can be difficult to cool such spaces by means of a ventilation system without creating draughts and causing discomfort for occupants. The use of a wall radiant cooling system is a suitable option for spaces...

Fast Water Transport in CNTs: length dependence and entrane/exit effects

DEFF Research Database (Denmark)

Walther, Jens Honore; Koumoutsakos, Petros

Superfast water transport in carbon nanotube (CNT) membranes has been reported in experimental studies. We use Molecular Dynamics simulations to elucidate the mechanisms of water entry, exit and transport in 2nm-diameter hydrophobic CNTs embedded in a hydrophilic membrane matrix. We demonstrate......, for the first time, that under imposed pressures of the order of 1 bar, water entry into the CNT cavity and exit from the CNT end, can occur only on pre-wetted membranes. We conduct large scale simulations for up to 500nm long CNTs and observe a previously unseen dependence of the flow enhancement rates...

Forthcoming EU Rules on Exit Taxes for Companies

NARCIS (Netherlands)

van de Streek, J.

2015-01-01

Rules on exit taxation for the EU as a whole are under construction at European Council level. Formally, the work on this piece of EU tax legislation is part of the controversial Common Consolidated Corporate Tax Base (CCCTB). But it is also thinkable that even without a CCCTB being established in

Customer Protest: Exit, Voice or Negative Word of Mouth

Directory of Open Access Journals (Sweden)

Solvang, B. K.

2008-01-01

Full Text Available Of the three forms of protest the propensity of word of mouth (WOM seems to be the most common, and the most exclusive form of protest seems to be exit. The propensity for voice lies in between. The costs linked to voice influence the propensity for WOM. The customers seem to do an evaluation between the three forms of protest, yet the rational picture of the customers should be moderated.Leaders should improve their treatment of the customers making complaints. The more they can treat customer complaints in an orderly and nice way the less informal negative word of mouth activity they will experience and they will reduce the exit propensity and lead the customers to the complain organisation. They should also ensure that their customers feel they get equal treatment by the staff.

Effects of thermal inflation on small scale density perturbations

Energy Technology Data Exchange (ETDEWEB)

Hong, Sungwook E. [School of Physics, Korea Institute for Advanced Study, 85 Hoegiro, Seoul 130-722 (Korea, Republic of); Lee, Hyung-Joo; Lee, Young Jae; Stewart, Ewan D. [Department of Physics, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 305-338 (Korea, Republic of); Zoe, Heeseung, E-mail: swhong@kias.re.kr, E-mail: ohsk111@kaist.ac.kr, E-mail: noasac@kaist.ac.kr, E-mail: jcap@profstewart.org, E-mail: heezoe@dgist.ac.kr [School of Basic Science, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno jungang-daero, Daegu 711-873 (Korea, Republic of)

2015-06-01

In cosmological scenarios with thermal inflation, extra eras of moduli matter domination, thermal inflation and flaton matter domination exist between primordial inflation and the radiation domination of Big Bang nucleosynthesis. During these eras, cosmological perturbations on small scales can enter and re-exit the horizon, modifying the power spectrum on those scales. The largest modified scale, k{sub b}, touches the horizon size when the expansion changes from deflation to inflation at the transition from moduli domination to thermal inflation. We analytically calculate the evolution of perturbations from moduli domination through thermal inflation and evaluate the curvature perturbation on the constant radiation density hypersurface at the end of thermal inflation to determine the late time curvature perturbation. Our resulting transfer function suppresses the power spectrum by a factor 0∼ 5 at k >> k{sub b}, with k{sub b} corresponding to anywhere from megaparsec to subparsec scales depending on the parameters of thermal inflation. Thus, thermal inflation might be constrained or detected by small scale observations such as CMB distortions or 21cm hydrogen line observations.

The molecular chaperone Hsp90 is required for cell cycle exit in Drosophila melanogaster.

Directory of Open Access Journals (Sweden)

Jennifer L Bandura

Full Text Available The coordination of cell proliferation and differentiation is crucial for proper development. In particular, robust mechanisms exist to ensure that cells permanently exit the cell cycle upon terminal differentiation, and these include restraining the activities of both the E2F/DP transcription factor and Cyclin/Cdk kinases. However, the full complement of mechanisms necessary to restrain E2F/DP and Cyclin/Cdk activities in differentiating cells are not known. Here, we have performed a genetic screen in Drosophila melanogaster, designed to identify genes required for cell cycle exit. This screen utilized a PCNA-miniwhite(+ reporter that is highly E2F-responsive and results in a darker red eye color when crossed into genetic backgrounds that delay cell cycle exit. Mutation of Hsp83, the Drosophila homolog of mammalian Hsp90, results in increased E2F-dependent transcription and ectopic cell proliferation in pupal tissues at a time when neighboring wild-type cells are postmitotic. Further, these Hsp83 mutant cells have increased Cyclin/Cdk activity and accumulate proteins normally targeted for proteolysis by the anaphase-promoting complex/cyclosome (APC/C, suggesting that APC/C function is inhibited. Indeed, reducing the gene dosage of an inhibitor of Cdh1/Fzr, an activating subunit of the APC/C that is required for timely cell cycle exit, can genetically suppress the Hsp83 cell cycle exit phenotype. Based on these data, we propose that Cdh1/Fzr is a client protein of Hsp83. Our results reveal that Hsp83 plays a heretofore unappreciated role in promoting APC/C function during cell cycle exit and suggest a mechanism by which Hsp90 inhibition could promote genomic instability and carcinogenesis.

The molecular chaperone Hsp90 is required for cell cycle exit in Drosophila melanogaster.

Science.gov (United States)

Bandura, Jennifer L; Jiang, Huaqi; Nickerson, Derek W; Edgar, Bruce A

2013-01-01

The coordination of cell proliferation and differentiation is crucial for proper development. In particular, robust mechanisms exist to ensure that cells permanently exit the cell cycle upon terminal differentiation, and these include restraining the activities of both the E2F/DP transcription factor and Cyclin/Cdk kinases. However, the full complement of mechanisms necessary to restrain E2F/DP and Cyclin/Cdk activities in differentiating cells are not known. Here, we have performed a genetic screen in Drosophila melanogaster, designed to identify genes required for cell cycle exit. This screen utilized a PCNA-miniwhite(+) reporter that is highly E2F-responsive and results in a darker red eye color when crossed into genetic backgrounds that delay cell cycle exit. Mutation of Hsp83, the Drosophila homolog of mammalian Hsp90, results in increased E2F-dependent transcription and ectopic cell proliferation in pupal tissues at a time when neighboring wild-type cells are postmitotic. Further, these Hsp83 mutant cells have increased Cyclin/Cdk activity and accumulate proteins normally targeted for proteolysis by the anaphase-promoting complex/cyclosome (APC/C), suggesting that APC/C function is inhibited. Indeed, reducing the gene dosage of an inhibitor of Cdh1/Fzr, an activating subunit of the APC/C that is required for timely cell cycle exit, can genetically suppress the Hsp83 cell cycle exit phenotype. Based on these data, we propose that Cdh1/Fzr is a client protein of Hsp83. Our results reveal that Hsp83 plays a heretofore unappreciated role in promoting APC/C function during cell cycle exit and suggest a mechanism by which Hsp90 inhibition could promote genomic instability and carcinogenesis.

Disseny de calefacció amb terra radiant d'una casa a l'horta de Lleida mitjançant energia geotèrmica

OpenAIRE

Fillat Sobrino, Jordi

2008-01-01

S'ha realitzat el disseny de calefacció d'una vivenda mitjançant energia geotèrmica de baixa temperatura, amb un bescanviador vertical de 80 m de profunditat. El sistema de calefacció és de terra radiant en forma d'espiral.

45 CFR 670.34 - Entry and exit ports.

Science.gov (United States)

2010-10-01

... ANTARCTIC ANIMALS AND PLANTS Import Into and Export From the United States § 670.34 Entry and exit ports. (a) Any native mammal, native bird, or native plants taken within Antarctica that are imported into or... Orleans, Louisiana. (7) New York, New York. (8) Seattle, Washington. (9) Dallas/Fort Worth, Texas. (10...

A simplified approach for exit dose in vivo measurements in radiotherapy and its clinical application

International Nuclear Information System (INIS)

Banjade, D.P.; Shukri, A.; Tajuddin, A.A.; Shrestha, S.L.; Bhat, M.

2002-01-01

This is a study using LiF:Mg;Ti thermoluminescent dosimeter (TLD) rods in phantoms to investigate the effect of lack of backscatter on exit dose. Comparing the measured dose with anticipated dose calculated using tissue maximum ratio (TMR) or percentage depth dose (PDD) gives rise to a correction factor. This correction factor may be applied to in-vivo dosimetry results to derive true dose to a point within the patient. Measurements in a specially designed humanoid breast phantom as well as patients undergoing radiotherapy treatment were also been done. TLDs with reproducibility of within ±3% (1 SD) are irradiated in a series of measurements for 6 and 10 MV photon beams from a medical linear accelerator. The measured exit doses for the different phantom thickness for 6 MV beams are found to be lowered by 10.9 to 14.0% compared to the dose derived from theoretical estimation (normalized dose at d max ). The same measurements for 10 MV beams are lowered by 9.0 to 13.5%. The variations of measured exit dose for different field sizes are found to be within 2.5%. The exit doses with added backscatter material from 2 mm up to 15 cm, shows gradual increase and the saturated values agreed within 1.5% with the expected results for both beams. The measured exit doses in humanoid breast phantom as well as in the clinical trial on patients undergoing radiotherapy also agreed with the predicted results based on phantom measurements. The authors' viewpoint is that this technique provides sufficient information to design exit surface bolus to restore build down effect in cases where part of the exit surface is being considered as a target volume. It indicates that the technique could be translated for in vivo dose measurements, which may be a conspicuous step of quality assurance in clinical practice. Copyright (2002) Australasian College of Physical Scientists and Engineers in Medicine

Association of rheumatic diseases with early exit from paid employment in Portugal.

Science.gov (United States)

Laires, Pedro A; Gouveia, Miguel

2014-04-01

To examine the association between rheumatic diseases (RD) and other chronic morbidity with early exit from paid employment in the Portuguese population. The study population consisted of all people between 50 and 64 years of age (3,762 men and 4,241 women) who participated in the Portuguese National Health Survey, conducted in 2005/2006. Data were collected on demographics, ill-health, lifestyle, and socioeconomic factors. Logistic regression was used to estimate the isolated effect of rheumatic diseases and other chronic diseases on the likelihood of exit from paid employment. At the time of the survey, 45.1 % of the Portuguese population with ages between 50 and 64 years old were not employed. In the nonemployed population, 31.6 % self-reported "poor" to "very poor" health, whereas 16.4 % did so in the employed population. A larger average number of major chronic diseases per capita were also found in those not employed (1.9 vs. 1.4, p paid employment. In particular, rheumatic diseases were more prevalent (43.4 vs. 32.1 %) and associated with early exit from work (OR 1.31; CI 1.12-1.52, p = 0.001). This study suggests an association between RD and other major chronic diseases with early exit from paid employment in Portugal. Thus, health and social protection policies should target these chronic disorders in order to better address sustainability issues and social protection effectiveness.

Airport exit and entry screening for Ebola--August-November 10, 2014.

Science.gov (United States)

Brown, Clive M; Aranas, Aaron E; Benenson, Gabrielle A; Brunette, Gary; Cetron, Marty; Chen, Tai-Ho; Cohen, Nicole J; Diaz, Pam; Haber, Yonat; Hale, Christa R; Holton, Kelly; Kohl, Katrin; Le, Amanda W; Palumbo, Gabriel J; Pearson, Kate; Phares, Christina R; Alvarado-Ramy, Francisco; Roohi, Shah; Rotz, Lisa D; Tappero, Jordan; Washburn, Faith M; Watkins, James; Pesik, Nicki

2014-12-12

In response to the largest recognized Ebola virus disease epidemic now occurring in West Africa, the governments of affected countries, CDC, the World Health Organization (WHO), and other international organizations have collaborated to implement strategies to control spread of the virus. One strategy recommended by WHO calls for countries with Ebola transmission to screen all persons exiting the country for "unexplained febrile illness consistent with potential Ebola infection." Exit screening at points of departure is intended to reduce the likelihood of international spread of the virus. To initiate this strategy, CDC, WHO, and other global partners were invited by the ministries of health of Guinea, Liberia, and Sierra Leone to assist them in developing and implementing exit screening procedures. Since the program began in August 2014, an estimated 80,000 travelers, of whom approximately 12,000 were en route to the United States, have departed by air from the three countries with Ebola transmission. Procedures were implemented to deny boarding to ill travelers and persons who reported a high risk for exposure to Ebola; no international air traveler from these countries has been reported as symptomatic with Ebola during travel since these procedures were implemented.

Toward electron exit wave tomography of amorphous materials at atomic resolution

Energy Technology Data Exchange (ETDEWEB)

Borisenko, Konstantin B., E-mail: konstantin.borisenko@materials.ox.ac.uk [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Moldovan, Grigore [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Kirkland, Angus I., E-mail: angus.kirkland@materials.ox.ac.uk [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Van Dyck, Dirk [Department of Physics, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium); Tang, Hsin-Yu; Chen, Fu-Rong [Department of Engineering and System Science, National Tsing Hua University, Kuang-Fu Road, 300 Hsinchu, Taiwan (China)

2012-09-25

Highlights: Black-Right-Pointing-Pointer We suggest a novel electron exit wave tomography approach to obtain three dimensional atomic structures of amorphous materials. Black-Right-Pointing-Pointer Theoretical tests using a model of amorphous Si doped with Au show that it is feasible to reconstruct both Si and Au atoms positions. Black-Right-Pointing-Pointer Reconstructions of the strongly scattering Au atoms positions appear to be insensitive to typical experimental errors. - Abstract: We suggest to use electron exit wave phase for tomographic reconstruction of structure of Au-doped amorphous Si with atomic resolution. In the present theoretical investigation into the approach it is found that the number of projections and the accuracy of defocus in the focal series restoration are the main factors that contribute to the final resolution. Although resolution is ultimately limited by these factors, phase shifts in the exit wave are sufficient to identify the position of Au atoms in an amorphous Si needle model, even when only 19 projections with defocus error of 4 nm are used. Electron beam damage will probably further limit the resolution of such tomographic reconstructions, however beam damage can be mitigated using lower accelerating voltages.

A balance of FGF and BMP signals regulates cell cycle exit and Equarin expression in lens cells

Science.gov (United States)

Jarrin, Miguel; Pandit, Tanushree; Gunhaga, Lena

2012-01-01

In embryonic and adult lenses, a balance of cell proliferation, cell cycle exit, and differentiation is necessary to maintain physical function. The molecular mechanisms regulating the transition of proliferating lens epithelial cells to differentiated primary lens fiber cells are poorly characterized. To investigate this question, we used gain- and loss-of-function analyses to modulate fibroblast growth factor (FGF) and/or bone morphogenetic protein (BMP) signals in chick lens/retina explants. Here we show that FGF activity plays a key role for proliferation independent of BMP signals. Moreover, a balance of FGF and BMP signals regulates cell cycle exit and the expression of Ccdc80 (also called Equarin), which is expressed at sites where differentiation of lens fiber cells occurs. BMP activity promotes cell cycle exit and induces Equarin expression in an FGF-dependent manner. In contrast, FGF activity is required but not sufficient to induce cell cycle exit or Equarin expression. Furthermore, our results show that in the absence of BMP activity, lens cells have increased cell cycle length or are arrested in the cell cycle, which leads to decreased cell cycle exit. Taken together, these findings suggest that proliferation, cell cycle exit, and early differentiation of primary lens fiber cells are regulated by counterbalancing BMP and FGF signals. PMID:22718906

Determination of the availability of core exit thermocouples during severe accident situations

International Nuclear Information System (INIS)

Edson, J.L.

1985-04-01

This report presents the findings and recommendations of the Nuclear Power Plant Instrumentation Evaluation (NPPIE) program concerning signal validation methods to determine the on-line availability of core exit thermocouples during accident situations. Methods of selecting appropriate signal validation techniques are discussed and sources of error identified. This report shows that through the use of these techniques the existence of high-temperature-caused errors may be detected as they occur. Specific recommendations for application of selected signal validation techniques to core exit thermocouples and other measurement systems are made. 23 refs., 22 figs., 3 tabs

Outdoor thermal comfort in public space in warm-humid Guayaquil, Ecuador

Science.gov (United States)

Johansson, Erik; Yahia, Moohammed Wasim; Arroyo, Ivette; Bengs, Christer

2018-03-01

The thermal environment outdoors affects human comfort and health. Mental and physical performance is reduced at high levels of air temperature being a problem especially in tropical climates. This paper deals with human comfort in the warm-humid city of Guayaquil, Ecuador. The main aim was to examine the influence of urban micrometeorological conditions on people's subjective thermal perception and to compare it with two thermal comfort indices: the physiologically equivalent temperature (PET) and the standard effective temperature (SET*). The outdoor thermal comfort was assessed through micrometeorological measurements of air temperature, humidity, mean radiant temperature and wind speed together with a questionnaire survey consisting of 544 interviews conducted in five public places of the city during both the dry and rainy seasons. The neutral and preferred values as well as the upper comfort limits of PET and SET* were determined. For both indices, the neutral values and upper thermal comfort limits were lower during the rainy season, whereas the preferred values were higher during the rainy season. Regardless of season, the neutral values of PET and SET* are above the theoretical neutral value of each index. The results show that local people accept thermal conditions which are above acceptable comfort limits in temperate climates and that the subjective thermal perception varies within a wide range. It is clear, however, that the majority of the people in Guayaquil experience the outdoor thermal environment during daytime as too warm, and therefore, it is important to promote an urban design which creates shade and ventilation.

Molecular signature of cell cycle exit induced in human T lymphoblasts by IL-2 withdrawal

Directory of Open Access Journals (Sweden)

Pfeifer Aleksandra

2009-06-01

Full Text Available Abstract Background The molecular mechanisms of cell cycle exit are poorly understood. Studies on lymphocytes at cell cycle exit after growth factor deprivation have predominantly focused on the initiation of apoptosis. We aimed to study gene expression profile of primary and immortalised IL-2-dependent human T cells forced to exit the cell cycle by growth factor withdrawal, before apoptosis could be evidenced. Results By the Affymetrix microarrays HG-U133 2.0 Plus, 53 genes were distinguished as differentially expressed before and soon after IL-2 deprivation. Among those, PIM1, BCL2, IL-8, HBEGF, DUSP6, OSM, CISH, SOCS2, SOCS3, LIF and IL13 were down-regulated and RPS24, SQSTM1, TMEM1, LRRC8D, ECOP, YY1AP1, C1orf63, ASAH1, SLC25A46 and MIA3 were up-regulated. Genes linked to transcription, cell cycle, cell growth, proliferation and differentiation, cell adhesion, and immune functions were found to be overrepresented within the set of the differentially expressed genes. Conclusion Cell cycle exit of the growth factor-deprived T lymphocytes is characterised by a signature of differentially expressed genes. A coordinate repression of a set of genes known to be induced during T cell activation is observed. However, growth arrest following exit from the cell cycle is actively controlled by several up-regulated genes that enforce the non-dividing state. The identification of genes involved in cell cycle exit and quiescence provides new hints for further studies on the molecular mechanisms regulating the non-dividing state of a cell, the mechanisms closely related to cancer development and to many biological processes.

The Effect of Exit-Site Antibacterial Honey Versus Nasal Mupirocin Prophylaxis on the Microbiology and Outcomes of Peritoneal Dialysis-Associated Peritonitis and Exit-Site Infections: A Sub-Study of the Honeypot Trial.

Science.gov (United States)

Zhang, Lei; Badve, Sunil V; Pascoe, Elaine M; Beller, Elaine; Cass, Alan; Clark, Carolyn; de Zoysa, Janak; Isbel, Nicole M; McTaggart, Steven; Morrish, Alicia T; Playford, E Geoffrey; Scaria, Anish; Snelling, Paul; Vergara, Liza A; Hawley, Carmel M; Johnson, David W

2015-12-01

♦ The HONEYPOT study recently reported that daily exit-site application of antibacterial honey was not superior to nasal mupirocin prophylaxis for preventing overall peritoneal dialysis (PD)-related infection. This paper reports a secondary outcome analysis of the HONEYPOT study with respect to exit-site infection (ESI) and peritonitis microbiology, infectious hospitalization and technique failure. ♦ A total of 371 PD patients were randomized to daily exit-site application of antibacterial honey plus usual exit-site care (N = 186) or intranasal mupirocin prophylaxis (in nasal Staphylococcus aureus carriers only) plus usual exit-site care (control, N = 185). Groups were compared on rates of organism-specific ESI and peritonitis, peritonitis- and infection-associated hospitalization, and technique failure (PD withdrawal). ♦ The mean peritonitis rates in the honey and control groups were 0.41 (95% confidence interval [CI] 0.32 - 0.50) and 0.41 (95% CI 0.33 - 0.49) episodes per patient-year, respectively (incidence rate ratio [IRR] 1.01, 95% CI 0.75 - 1.35). When specific causative organisms were examined, no differences were observed between the groups for gram-positive (IRR 0.99, 95% CI 0.66 - 1.49), gram-negative (IRR 0.71, 95% CI 0.39 - 1.29), culture-negative (IRR 2.01, 95% CI 0.91 - 4.42), or polymicrobial peritonitis (IRR 1.08, 95% CI 0.36 - 3.20). Exit-site infection rates were 0.37 (95% CI 0.28 - 0.45) and 0.33 (95% CI 0.26 - 0.40) episodes per patient-year for the honey and control groups, respectively (IRR 1.12, 95% CI 0.81 - 1.53). No significant differences were observed between the groups for gram-positive (IRR 1.10, 95% CI 0.70 - 1.72), gram-negative (IRR: 0.85, 95% CI 0.46 - 1.58), culture-negative (IRR 1.88, 95% CI 0.67 - 5.29), or polymicrobial ESI (IRR 1.00, 95% CI 0.40 - 2.54). Times to first peritonitis-associated and first infection-associated hospitalization were similar in the honey and control groups. The rates of technique failure (PD

EFFECT OF REVENUE INSURANCE ON ENTRY AND EXIT DECISIONS IN TABLE GRAPE PRODUCTION: A REAL OPTION APPROACH

OpenAIRE

Seo, Sangtaek; Salin, Victoria; Mitchell, Paul D.; Leatham, David J.

2004-01-01

This study determines the entry and exit thresholds of table grape farming with irreversible investment under uncertainty. Real option approach is adopted to consider the investment and management flexibility. Also revenue insurance is introduced to consider the effect of the risk management programs on the entry and exit thresholds. Results show that revenue insurance increases the entry and exit thresholds by 1% and 4%, respectively, thus discouraging new investment and current farming, as ...

Simulation of thermal indoor climate in buildings by using human Projected Area Factors

DEFF Research Database (Denmark)

Christensen, Jørgen Erik

2009-01-01

Nowadays many new and old buildings in Denmark have large glass surfaces. This is a consequence of the technical development of windows with low U-values that has made it possible to build houses with windows from floor to ceiling in northern climates. On the other hand if one is sitting close to...... for dynamic building thermal analysis. The method is demonstrated in a newer apartment with windows from floor to ceiling and shows how impotent it is to include the radiant effect from the glass sur-faces and how it influences the indoor thermal climate significantly.......Nowadays many new and old buildings in Denmark have large glass surfaces. This is a consequence of the technical development of windows with low U-values that has made it possible to build houses with windows from floor to ceiling in northern climates. On the other hand if one is sitting close...

Numerical Modeling of Conjugate Thermogravitational Convection in a Closed System with a Radiant Energy Source in Conditions of Convective-Radiative Heat Exchange at the External Boundary

Directory of Open Access Journals (Sweden)

Nee Alexander

2016-01-01

Full Text Available Mathematical modeling of conjugate natural convection in a closed rectangular cavity with a radiant energy source in conditions of convective-radiative heat exchange at the external boundary was conducted. The radiant energy distribution was set by the Lambert’s law. Conduction and convection processes analysis showed that the air masses flow pattern is modified slightly over the time. The temperature increases in the gas cavity, despite the heat removal from the one of the external boundary. According to the results of the integral heat transfer analysis were established that the average Nusselt number (Nuav increasing occurs up to τ = 200 (dimensionless time. Further Nuav has changed insignificantly due to the temperature field equalization near the interfaces “gas – wall”.

The Exit Gradient As a Measure of Groundwater Dependency of Watershed Ecosystem Services

Science.gov (United States)

Faulkner, B. R.; Canfield, T. J.; Justin, G. F.

2014-12-01

Flux of groundwater to surface water is often of great interest for the determination of the groundwater dependency of ecosystem services, such as maintenance of wetlands and of baseflow as a contributor to stream channel storage. It is difficult to measure. Most methods are based on coarse mass balance estimates or seepage meters. One drawback of these methods is they are not entirely spatially explicit. The exit gradient is commonly used in engineering studies of hydraulic structures affected by groundwater flow. It can be simply defined in the groundwater modeling context as the ratio of the difference between the computed head and the land surface elevation, for each computational cell, to the thickness of the cell, as it varies in space. When combined with calibrated groundwater flow models, it also has the potential to be useful in watershed scale evaluations of groundwater dependency in a spatially explicit way. We have taken advantage of calibrated models for the Calapooia watershed, Oregon, to map exit gradients for the watershed. Streams in the Calapooia are hydraulically well connected with groundwater. Not surprisingly, we found large variations in exit gradients between wet and dry season model runs, supporting the notion of stream expansion, as observed in the field, which may have a substantial influence on water quality. We have mapped the exit gradients in the wet and dry seasons, and compared them to regions which have been mapped in wetland surveys. Those classified as Palustrine types fell largest in the area of contribution from groundwater. In many cases, substantially high exit gradients, even on average, did not correspond to mapped wetland areas, yet nutrient retention ecosystem services may still be playing a role in these areas. The results also reinforce the notion of the importance of baseflow to maintenance of stream flow, even in the dry summer season in this Temperate/Mediterranean climate. Exit gradient mapping is a simple, yet

Curtain color and lighting program in broiler production: III - thermal comfort

Directory of Open Access Journals (Sweden)

Paulo Giovanni de Abreu

2011-09-01

Full Text Available The objective of this study was to evaluate the thermal comfort of broilers reared under two lighting programs (almost continuous and intermittent in broiler houses with yellow or blue lateral curtains. The experiment was carried out from June 24, 2004 until May 12, 2005. Six consecutive flocks were housed in four 12 × 10 m broilers houses internally divided into four pens of 200 birds each. Six flocks were raised on the same litter. The registration of data was accomplished at 3-hour intervals, for 24 hours twice a week. In the center of each pen and outside the house, dry and wet bulb temperatures, black globe temperature, and air velocity were collected. Based on the data collected at each time, air temperature (AT (ºC, black globe humidity temperature index (BGHTI, radiant thermal load (RTL (W/m², and relative air humidity (RH were determined. Harmonic analysis was used to estimate m, R, and f parameters. In general, the best results in terms of thermal comfort for the birds were found when near-continuous lighting program and yellow curtain were used.

Hydroelastic slamming of flexible wedges: Modeling and experiments from water entry to exit

Science.gov (United States)

Shams, Adel; Zhao, Sam; Porfiri, Maurizio

2017-03-01

Fluid-structure interactions during hull slamming are of great interest for the design of aircraft and marine vessels. The main objective of this paper is to establish a semi-analytical model to investigate the entire hydroelastic slamming of a wedge, from the entry to the exit phase. The structural dynamics is described through Euler-Bernoulli beam theory and the hydrodynamic loading is estimated using potential flow theory. A Galerkin method is used to obtain a reduced order modal model in closed-form, and a Newmark-type integration scheme is utilized to find an approximate solution. To benchmark the proposed semi-analytical solution, we experimentally investigate fluid-structure interactions through particle image velocimetry (PIV). PIV is used to estimate the velocity field, and the pressure is reconstructed by solving the incompressible Navier-Stokes equations from PIV data. Experimental results confirm that the flow physics and free-surface elevation during water exit are different from water entry. While water entry is characterized by positive values of the pressure field, with respect to the atmospheric pressure, the pressure field during water exit may be less than atmospheric. Experimental observations indicate that the location where the maximum pressure in the fluid is attained moves from the pile-up region to the keel, as the wedge reverses its motion from the entry to the exit stage. Comparing experimental results with semi-analytical findings, we observe that the model is successful in predicting the free-surface elevation and the overall distribution of the hydrodynamic loading on the wedge. These integrated experimental and theoretical analyses of water exit problems are expected to aid in the design of lightweight structures, which experience repeated slamming events during their operation.

Exit interviews administered to patients participating in the COSTOP placebo controlled randomised trial in Uganda

Directory of Open Access Journals (Sweden)

Andrew Nunn

2016-08-01

Discussion: The exit interview demonstrated that there was some evidence of open label drug being taken by the participants. However, the results from the interview do not suggest that the trial results would have been seriously compromised. We would recommend the exit interview as a valuable way of assessing adherence to trial procedures.

Optimal Scheduling of Residential Microgrids Considering Virtual Energy Storage System

Directory of Open Access Journals (Sweden)

Weiliang Liu

2018-04-01

Full Text Available The increasingly complex residential microgrids (r-microgrid consisting of renewable generation, energy storage systems, and residential buildings require a more intelligent scheduling method. Firstly, aiming at the radiant floor heating/cooling system widely utilized in residential buildings, the mathematical relationship between the operative temperature and heating/cooling demand is established based on the equivalent thermodynamic parameters (ETP model, by which the thermal storage capacity is analyzed. Secondly, the radiant floor heating/cooling system is treated as virtual energy storage system (VESS, and an optimization model based on mixed-integer nonlinear programming (MINLP for r-microgrid scheduling is established which takes thermal comfort level and economy as the optimization objectives. Finally, the optimal scheduling results of two typical r-microgrids are analyzed. Case studies demonstrate that the proposed scheduling method can effectively employ the thermal storage capacity of radiant floor heating/cooling system, thus lowering the operating cost of the r-microgrid effectively while ensuring the thermal comfort level of users.

New approach of a traditional analysis for predicting near-exit jet liquid instabilities

Science.gov (United States)

Jaramillo, Guillermo; Collicott, Steven

2015-11-01

Traditional linear instability theory for round liquid jets requires an exit-plane velocity profile be assumed so as to derive the characteristic growth rates and wavelengths of instabilities. This requires solving an eigenvalue problem for the Rayleigh Equation. In this new approach, a hyperbolic tangent velocity profile is assumed at the exit-plane of a round jet and a comparison is made with a hyperbolic secant profile. Temporal and Spatial Stability Analysis (TSA and SSA respectively) are the employed analytical tools to compare results of predicted most-unstable wavelengths from the given analytical velocity profiles and from previous experimental work. The local relevance of the velocity profile in the near-exit region of a liquid jet and the validity of an inviscid formulation through the Rayleigh equation are discussed as well. A comparison of numerical accuracy is made between two different mathematical approaches for the hyperbolic tangent profile with and without the Ricatti transformation. Reynolds number based on the momentum thickness of the boundary layer at the exit plane non-dimensionalizes the problem and, the Re range, based on measurements by Portillo in 2011, is 185 to 600. Wavelength measurements are taken from Portillo's experiment. School of Mechanical Engineering at Universidad del Valle, supported by a grant from Fulbright and Colciencias. Ph.D. student at the School of Aeronautics and Astronautics Purdue University.

Ecologies of ideologies: Explaining party entry and exit in West-European parliaments, 1945-2013.

Science.gov (United States)

van de Wardt, Marc; Berkhout, Joost; Vermeulen, Floris

2017-06-01

This study introduces a population-ecological approach to the entry and exit of political parties. A primary proposition of population ecology is that organizational entry and exit depends on the number of organizations already present: that is, density. We propose that political parties mainly experience competition from parties in the same ideological niche (left, centre, right). Pooled time-series analyses of 410 parties, 263 elections and 18 West-European countries largely support our expectations. We find that political parties are more likely to exit when density within their niche increases. Also there is competition between adjacent ideological niches, i.e. between centrist and right-wing niches. In contrast to our expectations, neither density nor institutional rules impact party entry. This raises important questions about the rationale of prospective entrants.

Prediction of midline dose from entrance ad exit dose using OSLD measurements for total irradiation

Energy Technology Data Exchange (ETDEWEB)

Choi, Chang Heon; Park, Jong Min; Park, So Yeon; Chun, Min Soo; Han, Ji Hye; Cho, Jin Dong; Kim, Jung In [Dept. of Radiation Oncology, Seoul National University Hospital, Seoul (Korea, Republic of)

2017-06-15

This study aims to predict the midline dose based on the entrance and exit doses from optically stimulated luminescence detector (OSLD) measurements for total body irradiation (TBI). For TBI treatment, beam data sets were measured for 6 MV and 15 MV beams. To evaluate the tissue lateral effect of various thicknesses, the midline dose and peak dose were measured using a solid water phantom (SWP) and ion chamber. The entrance and exit doses were measured using OSLDs. OSLDs were attached onto the central beam axis at the entrance and exit surfaces of the phantom. The predicted midline dose was evaluated as the sum of the entrance and exit doses by OSLD measurement. The ratio of the entrance dose to the exit dose was evaluated at various thicknesses. The ratio of the peak dose to the midline dose was 1.12 for a 30 cm thick SWP at both energies. When the patient thickness is greater than 30 cm, the 15 MV should be used to ensure dose homogeneity. The ratio of the entrance dose to the exit dose was less than 1.0 for thicknesses of less than 30 cm and 40 cm at 6 MV and 15 MV, respectively. Therefore, the predicted midline dose can be underestimated for thinner body. At 15 MV, the ratios were approximately 1.06 for a thickness of 50 cm. In cases where adult patients are treated with the 15 MV photon beam, it is possible for the predicted midline dose to be overestimated for parts of the body with a thickness of 50 cm or greater. The predicted midline dose and OSLD-measured midline dose depend on the phantom thickness. For in-vivo dosimetry of TBI, the measurement dose should be corrected in order to accurately predict the midline dose.

The use of an electronic portal imaging device for exit dosimetry and quality control measurements

International Nuclear Information System (INIS)

Kirby, Michael C.; Williams, Peter C.

1995-01-01

Purpose: To determine ways in which electronic portal imaging devices (EPIDs) could be used to (a) measure exit doses for external beam radiotherapy and (b) perform quality control checks on linear accelerators. Methods and Materials: When imaging, our fluoroscopic EPID adjusts the gain, offset, and frame acquisition time of the charge coupled device (CCD) camera automatically, to allow for the range of photon transmissions through the patient, and to optimize the signal-to-noise ratio. However, our EPID can be programmed to act as an integrating dosemeter. EPID dosemeter measurements were made for 20 MV photons, for different field sizes and thicknesses of unit density phantom material placed at varying exit surface to detector distances. These were compared with simultaneous Silicon diode exit dose measurements. Our exit dosimetry technique was verified using an anthropomorphic type phantom, and some initial measurements have been made for patients treated with irregularly shaped 20 MV x-ray fields. In this dosimetry mode, our EPID was also used to measure certain quality control parameters, x-ray field flatness, and the verification of segmented intensity modulated field prescriptions. Results: Configured for dosimetry, our EPID exhibited a highly linear response, capable of resolving individual monitor units. Exit doses could be measured to within about 3% of that measured using Silicon diodes. Field flatness was determined to within 1.5% of Farmer dosemeter measurements. Segmented intensity modulated fields can be easily verified. Conclusions: Our EPID has the versatility to assess a range of parameters pertinent to the delivery of high quality, high precision radiotherapy. When configured appropriately, it can measure exit doses in vivo, with reasonable accuracy, perform certain quick quality control checks, and analyze segmented intensity modulated treatment fields

Exit, voice and loyalty in Kenya's French bean industry: What ...

African Journals Online (AJOL)

response affected their continued participation in the supermarket business. It applies Hirschman's concept of exit, voice and loyalty to assess the strategies used by ... This strategy of compliance with IFSS has since become the model in

On a mean field game optimal control approach modeling fast exit scenarios in human crowds

KAUST Repository

Burger, Martin; Di Francesco, Marco; Markowich, Peter A.; Wolfram, Marie Therese

2013-01-01

The understanding of fast exit and evacuation situations in crowd motion research has received a lot of scientific interest in the last decades. Security issues in larger facilities, like shopping malls, sports centers, or festivals necessitate a better understanding of the major driving forces in crowd dynamics. In this paper we present an optimal control approach modeling fast exit scenarios in pedestrian crowds. The model is formulated in the framework of mean field games and based on a parabolic optimal control problem. We consider the case of a large human crowd trying to exit a room as fast as possible. The motion of every pedestrian is determined by minimizing a cost functional, which depends on his/her position and velocity, the overall density of people, and the time to exit. This microscopic setup leads in a mean-field formulation to a nonlinear macroscopic optimal control problem, which raises challenging questions for the analysis and numerical simulations.We discuss different aspects of the mathematical modeling and illustrate them with various computational results. ©2013 IEEE.

On a mean field game optimal control approach modeling fast exit scenarios in human crowds

KAUST Repository

Burger, Martin

2013-12-01

The understanding of fast exit and evacuation situations in crowd motion research has received a lot of scientific interest in the last decades. Security issues in larger facilities, like shopping malls, sports centers, or festivals necessitate a better understanding of the major driving forces in crowd dynamics. In this paper we present an optimal control approach modeling fast exit scenarios in pedestrian crowds. The model is formulated in the framework of mean field games and based on a parabolic optimal control problem. We consider the case of a large human crowd trying to exit a room as fast as possible. The motion of every pedestrian is determined by minimizing a cost functional, which depends on his/her position and velocity, the overall density of people, and the time to exit. This microscopic setup leads in a mean-field formulation to a nonlinear macroscopic optimal control problem, which raises challenging questions for the analysis and numerical simulations.We discuss different aspects of the mathematical modeling and illustrate them with various computational results. ©2013 IEEE.

Drivers' Visual Characteristics when Merging onto or Exiting an Urban Expressway.

Directory of Open Access Journals (Sweden)

Ying Cheng

Full Text Available The aim of this study is to examine drivers' visual and driving behavior while merging onto or exiting an urban expressway with low and high traffic densities. The analysis was conducted according to three periods (approaching, merging or exiting, and accelerating or decelerating. A total of 10 subjects (8 males and 2 females with ages ranging from 25 to 52 years old (M = 30.0 years old participated in the study. The research was conducted in a natural driving situation, and the drivers' eye movements were monitored and recorded using an eye tracking system. The results show that the influence of traffic density on the glance duration and scan duration is more significant when merging than when exiting. The results also demonstrate that the number of glances and the mean glance duration are mainly related to the driving task (e.g., the merging period. Therefore, drivers' visual search strategies mainly depend on the current driving task. With regard to driving behavior, the variation tendencies of the duration and the velocity of each period are similar. These results support building an automated driving assistant system that can automatically identify gaps and accelerate or decelerate the car accordingly or provide suggestions to the driver to do so.

High resolution electron exit wave reconstruction from a diffraction pattern using Gaussian basis decomposition

International Nuclear Information System (INIS)

Borisenko, Konstantin B; Kirkland, Angus I

2014-01-01

We describe an algorithm to reconstruct the electron exit wave of a weak-phase object from single diffraction pattern. The algorithm uses analytic formulations describing the diffraction intensities through a representation of the object exit wave in a Gaussian basis. The reconstruction is achieved by solving an overdetermined system of non-linear equations using an easily parallelisable global multi-start search with Levenberg-Marquard optimisation and analytic derivatives

Hedgehog signaling acts with the temporal cascade to promote neuroblast cell cycle exit.

Directory of Open Access Journals (Sweden)

Phing Chian Chai

Full Text Available In Drosophila postembryonic neuroblasts, transition in gene expression programs of a cascade of transcription factors (also known as the temporal series acts together with the asymmetric division machinery to generate diverse neurons with distinct identities and regulate the end of neuroblast proliferation. However, the underlying mechanism of how this "temporal series" acts during development remains unclear. Here, we show that Hh signaling in the postembryonic brain is temporally regulated; excess (earlier onset of Hh signaling causes premature neuroblast cell cycle exit and under-proliferation, whereas loss of Hh signaling causes delayed cell cycle exit and excess proliferation. Moreover, the Hh pathway functions downstream of Castor but upstream of Grainyhead, two components of the temporal series, to schedule neuroblast cell cycle exit. Interestingly, hh is likely a target of Castor. Hence, Hh signaling provides a link between the temporal series and the asymmetric division machinery in scheduling the end of neurogenesis.

Experimental investigation of the influence of the air jet trajectory on convective heat transfer in buildings equipped with air-based and radiant cooling systems

DEFF Research Database (Denmark)

Le Dreau, Jerome; Heiselberg, Per; Jensen, Rasmus Lund

2015-01-01

-state and dynamic conditions. With the air-based cooling system, a dependency of the convective heat transfer on the air jet trajectory has been observed. New correlations have been developed, introducing a modified Archimedes number to account for the air flow pattern. The accuracy of the new correlations has been...... evaluated to±15%. Besides the study with an air-based cooling system, the convective heat transfer with a radiant cooling system has also been investigated. The convective flow at the activated surface is mainly driven by natural convection. For other surfaces, the complexity of the flow and the large......The complexity and diversity of airflow in buildings make the accurate definition of convective heat transfer coefficients (CHTCs) difficult. In a full-scale test facility, the convective heat transfer of two cooling systems (active chilled beam and radiant wall) has been investigated under steady...

Simbol-X Mirror Module Thermal Shields: I-Design and X-Ray Transmission

Science.gov (United States)

Collura, A.; Barbera, M.; Varisco, S.; Basso, S.; Pareschi, G.; Tagliaferri, G.; Ayers, T.

2009-05-01

The Simbol-X mission is designed to fly in formation flight configuration. As a consequence, the telescope has both ends open to space, and thermal shielding at telescope entrance and exit is required to maintain temperature uniformity throughout the mirrors. Both mesh and meshless solutions are presently under study for the shields. We discuss the design and the X-ray transmission.

Simbol-X Mirror Module Thermal Shields: I - Design and X-Ray Transmission

International Nuclear Information System (INIS)

Collura, A.; Varisco, S.; Barbera, M.; Basso, S.; Pareschi, G.; Tagliaferri, G.; Ayers, T.

2009-01-01

The Simbol-X mission is designed to fly in formation flight configuration. As a consequence, the telescope has both ends open to space, and thermal shielding at telescope entrance and exit is required to maintain temperature uniformity throughout the mirrors. Both mesh and meshless solutions are presently under study for the shields. We discuss the design and the X-ray transmission.

Prediction of Thermal Environment in a Large Space Using Artificial Neural Network

Directory of Open Access Journals (Sweden)

Hyun-Jung Yoon

2018-02-01

Full Text Available Since the thermal environment of large space buildings such as stadiums can vary depending on the location of the stands, it is important to divide them into different zones and evaluate their thermal environment separately. The thermal environment can be evaluated using physical values measured with the sensors, but the occupant density of the stadium stands is high, which limits the locations available to install the sensors. As a method to resolve the limitations of installing the sensors, we propose a method to predict the thermal environment of each zone in a large space. We set six key thermal factors affecting the thermal environment in a large space to be predicted factors (indoor air temperature, mean radiant temperature, and clothing and the fixed factors (air velocity, metabolic rate, and relative humidity. Using artificial neural network (ANN models and the outdoor air temperature and the surface temperature of the interior walls around the stands as input data, we developed a method to predict the three thermal factors. Learning and verification datasets were established using STAR CCM+ (2016.10, Siemens PLM software, Plano, TX, USA. An analysis of each model’s prediction results showed that the prediction accuracy increased with the number of learning data points. The thermal environment evaluation process developed in this study can be used to control heating, ventilation, and air conditioning (HVAC facilities in each zone in a large space building with sufficient learning by ANN models at the building testing or the evaluation stage.

Clouds and the Earth's Radiant Energy System (CERES) Data Products for Climate Research

Science.gov (United States)

Kato, Seiji; Loeb, Norman G.; Rutan, David A.; Rose, Fred G.

2015-01-01

NASA's Clouds and the Earth's Radiant Energy System (CERES) project integrates CERES, Moderate Resolution Imaging Spectroradiometer (MODIS), and geostationary satellite observations to provide top-of-atmosphere (TOA) irradiances derived from broadband radiance observations by CERES instruments. It also uses snow cover and sea ice extent retrieved from microwave instruments as well as thermodynamic variables from reanalysis. In addition, these variables are used for surface and atmospheric irradiance computations. The CERES project provides TOA, surface, and atmospheric irradiances in various spatial and temporal resolutions. These data sets are for climate research and evaluation of climate models. Long-term observations are required to understand how the Earth system responds to radiative forcing. A simple model is used to estimate the time to detect trends in TOA reflected shortwave and emitted longwave irradiances.

Ecologies of Ideologies: Explaining Party Entry and Exit in West-European Parliaments, 1945-2013

OpenAIRE

van de Wardt, M.; Berkhout, J.; Vermeulen, F.

2017-01-01

This study introduces a population-ecological approach to the entry and exit of political parties. A primary proposition of population ecology is that organizational entry and exit depends on the number of organizations already present: that is, density. We propose that political parties mainly experience competition from parties in the same ideological niche (left, centre, right). Pooled time-series analyses of 410 parties, 263 elections and 18 West-European countries largely support our exp...

Spanish exit polls. Sampling error or nonresponse bias?

Directory of Open Access Journals (Sweden)

Pavía, Jose M.

2016-09-01

Full Text Available Countless examples of misleading forecasts on behalf of both pre-election and exit polls can be found all over the world. Non-representative samples due to differential nonresponse have been claimed as being the main reason for inaccurate exit-poll projections. In real inference problems, it is seldom possible to compare estimates and true values. Electoral forecasts are an exception. Comparisons between estimates and final outcomes can be carried out once votes have been tallied. In this paper, we examine the raw data collected in seven exit polls conducted in Spain and test the likelihood that the data collected in each sampled voting location can be considered as a random sample of actual results. Knowing the answer to this is relevant for both electoral analysts and forecasters as, if the hypothesis is rejected, the shortcomings of the collected data would need amending. Analysts could improve the quality of their computations by implementing local correction strategies. We find strong evidence of nonsampling error in Spanish exit polls and evidence that the political context matters. Nonresponse bias is larger in polarized elections and in a climate of fearExiste un gran número de ejemplos de predicciones inexactas obtenidas a partir tanto de encuestas pre-electorales como de encuestas a pie de urna a lo largo del mundo. La presencia de tasas de no-respuesta diferencial entre distintos tipos de electores ha sido la principal razón esgrimida para justificar las proyecciones erróneas en las encuestas a pie de urna. En problemas de inferencia rara vez es posible comparar estimaciones y valores reales. Las predicciones electorales son una excepción. La comparación entre estimaciones y resultados finales puede realizarse una vez los votos han sido contabilizados. En este trabajo, examinamos los datos brutos recogidos en siete encuestas a pie de urna realizadas en España y testamos la hipótesis de que los datos recolectados en cada punto

Performance of radiant cooling ceiling combined with personalized ventilation in an office room: identification of thermal conditions

DEFF Research Database (Denmark)

Lipczynska, Aleksandra; Kaczmarczyk, Jan; Melikov, Arsen Krikor

2014-01-01

were performed in a test room arranged as an office with 2 workstations and 2 seating occupants resembled by thermal manikins. Heat gain of 66-72 W/m2 was simulated in the room (occupants, computers, lighting, solar gain). The air temperature in the chamber was maintained at 26°C and 28°C. Personalized...

The effect of urban geometry on mean radiant temperature under future climate change: a study of three European cities.

Science.gov (United States)

Lau, Kevin Ka-Lun; Lindberg, Fredrik; Rayner, David; Thorsson, Sofia

2015-07-01

Future anthropogenic climate change is likely to increase the air temperature (T(a)) across Europe and increase the frequency, duration and magnitude of severe heat stress events. Heat stress events are generally associated with clear-sky conditions and high T(a), which give rise to high radiant heat load, i.e. mean radiant temperature (T(mrt)). In urban environments, T mrt is strongly influenced by urban geometry. The present study examines the effect of urban geometry on daytime heat stress in three European cities (Gothenburg in Sweden, Frankfurt in Germany and Porto in Portugal) under present and future climates, using T(mrt) as an indicator of heat stress. It is found that severe heat stress occurs in all three cities. Similar maximum daytime T(mrt) is found in open areas in all three cities despite of the latitudinal differences in average daytime T(mrt). In contrast, dense urban structures like narrow street canyons are able to mitigate heat stress in the summer, without causing substantial changes in T(mrt) in the winter. Although the T(mrt) averages are similar for the north-south and east-west street canyons in each city, the number of hours when T(mrt) exceeds the threshold values of 55.5 and 59.4 °C-used as indicators of moderate and severe heat stress-in the north-south canyons is much higher than that in the east-west canyons. Using statistically downscaled data from a regional climate model, it is found that the study sites were generally warmer in the future scenario, especially Porto, which would further exacerbate heat stress in urban areas. However, a decrease in solar radiation in Gothenburg and Frankfurt reduces T(mrt) in the spring, while the reduction in T(mrt) is somewhat offset by increasing T(a) in other seasons. It suggests that changes in the T(mrt) under the future scenario are dominated by variations in T(a). Nonetheless, the intra-urban differences remain relatively stable in the future. These findings suggest that dense urban

A critical examination of the validity of simplified models for radiant heat transfer analysis.

Science.gov (United States)

Toor, J. S.; Viskanta, R.

1972-01-01

Examination of the directional effects of the simplified models by comparing the experimental data with the predictions based on simple and more detailed models for the radiation characteristics of surfaces. Analytical results indicate that the constant property diffuse and specular models do not yield the upper and lower bounds on local radiant heat flux. In general, the constant property specular analysis yields higher values of irradiation than the constant property diffuse analysis. A diffuse surface in the enclosure appears to destroy the effect of specularity of the other surfaces. Semigray and gray analyses predict the irradiation reasonably well provided that the directional properties and the specularity of the surfaces are taken into account. The uniform and nonuniform radiosity diffuse models are in satisfactory agreement with each other.

Thermal and ultrasonic influence in the formation of nanometer scale hydroxyapatite bio-ceramic

Science.gov (United States)

Poinern, GJE; Brundavanam, R; Le, X Thi; Djordjevic, S; Prokic, M; Fawcett, D

2011-01-01

Hydroxyapatite (HAP) is a widely used biocompatible ceramic in many biomedical applications and devices. Currently nanometer-scale forms of HAP are being intensely investigated due to their close similarity to the inorganic mineral component of the natural bone matrix. In this study nano-HAP was prepared via a wet precipitation method using Ca(NO3)2 and KH2PO4 as the main reactants and NH4OH as the precipitator under ultrasonic irradiation. The Ca/P ratio was set at 1.67 and the pH was maintained at 9 during the synthesis process. The influence of the thermal treatment was investigated by using two thermal treatment processes to produce ultrafine nano-HAP powders. In the first heat treatment, a conventional radiant tube furnace was used to produce nano-particles with an average size of approximately 30 nm in diameter, while the second thermal treatment used a microwave-based technique to produce particles with an average diameter of 36 nm. The crystalline structure and morphology of all nanoparticle powders produced were investigated using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR). Both thermal techniques effectively produced ultrafine powders with similar crystalline structure, morphology and particle sizes. PMID:22114473

Repressive histone methylation regulates cardiac myocyte cell cycle exit.

Science.gov (United States)

El-Nachef, Danny; Oyama, Kyohei; Wu, Yun-Yu; Freeman, Miles; Zhang, Yiqiang; Robb MacLellan, W

2018-05-22

Mammalian cardiac myocytes (CMs) stop proliferating soon after birth and subsequent heart growth comes from hypertrophy, limiting the adult heart's regenerative potential after injury. The molecular events that mediate CM cell cycle exit are poorly understood. To determine the epigenetic mechanisms limiting CM cycling in adult CMs (ACMs) and whether trimethylation of lysine 9 of histone H3 (H3K9me3), a histone modification associated with repressed chromatin, is required for the silencing of cell cycle genes, we developed a transgenic mouse model where H3K9me3 is specifically removed in CMs by overexpression of histone demethylase, KDM4D. Although H3K9me3 is found across the genome, its loss in CMs preferentially disrupts cell cycle gene silencing. KDM4D binds directly to cell cycle genes and reduces H3K9me3 levels at these promotors. Loss of H3K9me3 preferentially leads to increased cell cycle gene expression resulting in enhanced CM cycling. Heart mass was increased in KDM4D overexpressing mice by postnatal day 14 (P14) and continued to increase until 9-weeks of age. ACM number, but not size, was significantly increased in KDM4D expressing hearts, suggesting CM hyperplasia accounts for the increased heart mass. Inducing KDM4D after normal development specifically in ACMs resulted in increased cell cycle gene expression and cycling. We demonstrated that H3K9me3 is required for CM cell cycle exit and terminal differentiation in ACMs. Depletion of H3K9me3 in adult hearts prevents and reverses permanent cell cycle exit and allows hyperplastic growth in adult hearts in vivo. Copyright © 2017. Published by Elsevier Ltd.

Thermal performance of a micro-combustor for micro-gas turbine system

International Nuclear Information System (INIS)

Cao, H.L.; Xu, J.L.

2007-01-01

Premixed combustion of hydrogen gas and air was performed in a stainless steel based micro-annular combustor for a micro-gas turbine system. Micro-scale combustion has proved to be stable in the micro-combustor with a gap of 2 mm. The operating range of the micro-combustor was measured, and the maximum excess air ratio is up to 4.5. The distribution of the outer wall temperature and the temperature of exhaust gas of the micro-combustor with excess air ratio were obtained, and the wall temperature of the micro-combustor reaches its maximum value at the excess air ratio of 0.9 instead of 1 (stoichiometric ratio). The heat loss of the micro-combustor to the environment was calculated and even exceeds 70% of the total thermal power computed from the consumed hydrogen mass flow rate. Moreover, radiant heat transfer covers a large fraction of the total heat loss. Measures used to reduce the heat loss were proposed to improve the thermal performance of the micro-combustor. The optimal operating status of the micro-combustor and micro-gas turbine is analyzed and proposed by analyzing the relationship of the temperature of the exhaust gas of the micro-combustor with thermal power and excess air ratio. The investigation of the thermal performance of the micro-combustor is helpful to design an improved micro-combustor

Thermal Modeling of a Hybrid Thermoelectric Solar Collector with a Compound Parabolic Concentrator

Science.gov (United States)

Lertsatitthanakorn, C.; Jamradloedluk, J.; Rungsiyopas, M.

2013-07-01

In this study radiant light from the sun is used by a hybrid thermoelectric (TE) solar collector and a compound parabolic concentrator (CPC) to generate electricity and thermal energy. The hybrid TE solar collector system described in this report is composed of transparent glass, an air gap, an absorber plate, TE modules, a heat sink to cool the water, and a storage tank. Incident solar radiation falls on the CPC, which directs and reflects the radiation to heat up the absorber plate, creating a temperature difference across the TE modules. The water, which absorbs heat from the hot TE modules, flows through the heat sink to release its heat. The results show that the electrical power output and the conversion efficiency depend on the temperature difference between the hot and cold sides of the TE modules. A maximum power output of 1.03 W and a conversion efficiency of 0.6% were obtained when the temperature difference was 12°C. The thermal efficiency increased as the water flow rate increased. The maximum thermal efficiency achieved was 43.3%, corresponding to a water flow rate of 0.24 kg/s. These experimental results verify that using a TE solar collector with a CPC to produce both electrical power and thermal energy seems to be feasible. The thermal model and calculation method can be applied for performance prediction.

The Right of Exit in the Context of Multiculturalism

Directory of Open Access Journals (Sweden)

Ana Maria D'Ávila Lopes

2015-12-01

Full Text Available http://dx.doi.org/10.5007/2177-7055.2015v36n71p155 The terrorist attack on the Twin Towers in the United States provoked heated discussions about the need to limit and control the performance of some cultural minorities, as well as to create mechanisms to protect members of these minorities against the decisions taken by the group. In this context, this paper aims to analyze the possibilities and limits of the right of exit in the context of Multiculturalism. To this end, a literature research was performed in national and foreign doctrine. After analyzing the data, it was found that the right to exit is a valuable mechanism for protecting members of cultural minorities, however, there are situations, especially in cases where the values of the group are internalized by the members, in which this right is insufficient and should be supplemented by other human rights.

Solar hybrid cooling system for high-tech offices in subtropical climate - Radiant cooling by absorption refrigeration and desiccant dehumidification

International Nuclear Information System (INIS)

Fong, K.F.; Chow, T.T.; Lee, C.K.; Lin, Z.; Chan, L.S.

2011-01-01

Highlights: → A solar hybrid cooling system is proposed for high-tech offices in subtropical climate. → An integration of radiant cooling, absorption refrigeration and desiccant dehumidification. → Year-round cooling and energy performances were evaluated through dynamic simulation. → Its annual primary energy consumption was lower than conventional system up to 36.5%. → The passive chilled beams were more energy-efficient than the active chilled beams. - Abstract: A solar hybrid cooling design is proposed for high cooling load demand in hot and humid climate. For the typical building cooling load, the system can handle the zone cooling load (mainly sensible) by radiant cooling with the chilled water from absorption refrigeration, while the ventilation load (largely latent) by desiccant dehumidification. This hybrid system utilizes solar energy for driving the absorption chiller and regenerating the desiccant wheel. Since a high chilled water temperature generated from the absorption chiller is not effective to handle the required latent load, desiccant dehumidification is therefore involved. It is an integration of radiant cooling, absorption refrigeration and desiccant dehumidification, which are powered up by solar energy. In this study, the application potential of the solar hybrid cooling system was evaluated for the high-tech offices in the subtropical climate through dynamic simulation. The high-tech offices are featured with relatively high internal sensible heat gains due to the intensive office electric equipment. The key performance indicators included the solar fraction and the primary energy consumption. Comparative study was also carried out for the solar hybrid cooling system using two common types of chilled ceilings, the passive chilled beams and active chilled beams. It was found that the solar hybrid cooling system was technically feasible for the applications of relatively higher cooling load demand. The annual primary energy

Thermally-Induced Structural Disturbances of Rigid Panel Solar Arrays

Science.gov (United States)

Johnston, John D.; Thornton, Earl A.

1997-01-01

The performance of a significant number of spacecraft has been impacted negatively by attitude disturbances resulting from thermally-induced motions of flexible structures. Recent examples of spacecraft affected by these disturbances include the Hubble Space Telescope (HST) and the Upper Atmosphere Research Satellite (UARS). Thermally-induced structural disturbances occur as the result of rapid changes in thermal loading typically initiated as a satellite exits or enters the Earth's shadow. Temperature differences in flexible appendages give rise to structural deformations, which in turn result in disturbance torques reacting back on the spacecraft. Structures which have proven susceptible to these disturbances include deployable booms and solar arrays. This paper investigates disturbances resulting from thermally-induced deformations of rigid panel solar arrays. An analytical model for the thermal-structural response of the solar array and the corresponding disturbance torque are presented. The effect of these disturbances on the attitude dynamics of a simple spacecraft is then investigated using a coupled system of governing equations which includes the effects of thermally-induced deformations. Numerical results demonstrate the effect of varying solar array geometry on the dynamic response of the system.

General Relativistic Radiant Shock Waves in the Post-Quasistatic Approximation

Energy Technology Data Exchange (ETDEWEB)

H, Jorge A Rueda [Centro de Fisica Fundamental, Universidad de Los Andes, Merida 5101, Venezuela Escuela de Fisica, Universidad Industrial de Santander, A.A. 678, Bucaramanga (Colombia); Nunez, L A [Centro de Fisica Fundamental, Universidad de Los Andes, Merida 5101, Venezuela Centro Nacional de Calculo Cientifico, Universidad de Los Andes, CeCalCULA, Corporacion Parque Tecnologico de Merida, Merida 5101, Venezuela (Venezuela)

2007-05-15

An evolution of radiant shock wave front is considered in the framework of a recently presented method to study self-gravitating relativistic spheres, whose rationale becomes intelligible and finds full justification within the context of a suitable definition of the post-quasistatic approximation. The spherical matter configuration is divided into two regions by the shock and each side of the interface having a different equation of state and anisotropic phase. In order to simulate dissipation effects due to the transfer of photons and/or neutrinos within the matter configuration, we introduce the flux factor, the variable Eddington factor and a closure relation between them. As we expected the strong of the shock increases the speed of the fluid to relativistic ones and for some critical values is larger than light speed. In addition, we find that energy conditions are very sensible to the anisotropy, specially the strong energy condition. As a special feature of the model, we find that the contribution of the matter and radiation to the radial pressure are the same order of magnitude as in the mant as in the core, moreover, in the core radiation pressure is larger than matter pressure.

General Relativistic Radiant Shock Waves in the Post-Quasistatic Approximation

International Nuclear Information System (INIS)

H, Jorge A Rueda; Nunez, L A

2007-01-01

An evolution of radiant shock wave front is considered in the framework of a recently presented method to study self-gravitating relativistic spheres, whose rationale becomes intelligible and finds full justification within the context of a suitable definition of the post-quasistatic approximation. The spherical matter configuration is divided into two regions by the shock and each side of the interface having a different equation of state and anisotropic phase. In order to simulate dissipation effects due to the transfer of photons and/or neutrinos within the matter configuration, we introduce the flux factor, the variable Eddington factor and a closure relation between them. As we expected the strong of the shock increases the speed of the fluid to relativistic ones and for some critical values is larger than light speed. In addition, we find that energy conditions are very sensible to the anisotropy, specially the strong energy condition. As a special feature of the model, we find that the contribution of the matter and radiation to the radial pressure are the same order of magnitude as in the mant as in the core, moreover, in the core radiation pressure is larger than matter pressure

KLF4 Nuclear Export Requires ERK Activation and Initiates Exit from Naive Pluripotency.

Science.gov (United States)

Dhaliwal, Navroop K; Miri, Kamelia; Davidson, Scott; Tamim El Jarkass, Hala; Mitchell, Jennifer A

2018-04-10

Cooperative action of a transcription factor complex containing OCT4, SOX2, NANOG, and KLF4 maintains the naive pluripotent state; however, less is known about the mechanisms that disrupt this complex, initiating exit from pluripotency. We show that, as embryonic stem cells (ESCs) exit pluripotency, KLF4 protein is exported from the nucleus causing rapid decline in Nanog and Klf4 transcription; as a result, KLF4 is the first pluripotency transcription factor removed from transcription-associated complexes during differentiation. KLF4 nuclear export requires ERK activation, and phosphorylation of KLF4 by ERK initiates interaction of KLF4 with nuclear export factor XPO1, leading to KLF4 export. Mutation of the ERK phosphorylation site in KLF4 (S132) blocks KLF4 nuclear export, the decline in Nanog, Klf4, and Sox2 mRNA, and differentiation. These findings demonstrate that relocalization of KLF4 to the cytoplasm is a critical first step in exit from the naive pluripotent state and initiation of ESC differentiation. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Organized medicine and Scandinavian professional unionism: hospital policies and exit options in Denmark and Sweden.

Science.gov (United States)

Heidenheimer, A J; Johansen, L N

1985-01-01

Strikes by junior hospital doctors over the issue of on-call remuneration in Denmark and Sweden in 1981 are analyzed to clarify the impact of public-sector cost-control policies on intra- and interprofessional solidarity within the Scandinavian professional peak associations. The junior doctors' grievances could find expression either through increased "voice" within the medical negotiating machinery, or by pursuing the exit option in having the medical associations quit the peak associations. The article explains why the "exit" option was selected in Denmark, while in Sweden the granting of additional voice helped persuade the medical association to withdraw its exit threat and to remain within the peak association. The two cases are interpreted as presaging a divergence in the paths being taken by the various Scandinavian welfare states.

Ecologies of ideologies: Explaining party entry and exit in West-European parliaments, 1945–2013

Science.gov (United States)

Berkhout, Joost; Vermeulen, Floris

2016-01-01

This study introduces a population-ecological approach to the entry and exit of political parties. A primary proposition of population ecology is that organizational entry and exit depends on the number of organizations already present: that is, density. We propose that political parties mainly experience competition from parties in the same ideological niche (left, centre, right). Pooled time-series analyses of 410 parties, 263 elections and 18 West-European countries largely support our expectations. We find that political parties are more likely to exit when density within their niche increases. Also there is competition between adjacent ideological niches, i.e. between centrist and right-wing niches. In contrast to our expectations, neither density nor institutional rules impact party entry. This raises important questions about the rationale of prospective entrants. PMID:29046613

A correlation linking the predicted mean vote and the mean thermal vote based on an investigation on the human thermal comfort in short-haul domestic flights.

Science.gov (United States)

Giaconia, Carlo; Orioli, Aldo; Di Gangi, Alessandra

2015-05-01

The results of an experimental investigation on the human thermal comfort inside the cabin of some Airbus A319 aircrafts during 14 short-haul domestic flights, linking various Italian cities, are presented and used to define a correlation among the predicted mean vote (PMV), a procedure which is commonly used to assess the thermal comfort in inhabited environments, and the equivalent temperature and mean thermal vote (MTV), which are the parameters suggested by the European Standard EN ISO 14505-2 for the evaluation of the thermal environment in vehicles. The measurements of the radiant temperature, air temperature and relative humidity during flights were performed. The air temperature varied between 22.2 °C and 26.0 °C; the relative humidity ranged from 8.7% to 59.2%. The calculated values of the PMV varied from -0.16 to 0.90 and were confirmed by the answers of the passengers. The equivalent temperature was evaluated using the equations of Fanger or on the basis of the values of the skin temperature measured on some volunteers. The correlation linking the thermal sensation scales and zones used by the PMV and the MTV resulted quite accurate because the minimum value of the absolute difference between such environmental indexes equalled 0.0073 and the maximum difference did not exceed the value of 0.0589. Even though the equivalent temperature and the MTV were specifically proposed to evaluate the thermal sensation in vehicles, their use may be effectively extended to the assessment of the thermal comfort in airplanes or other occupied places. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

A smooth exit from eternal inflation?

Science.gov (United States)

Hawking, S. W.; Hertog, Thomas

2018-04-01

The usual theory of inflation breaks down in eternal inflation. We derive a dual description of eternal inflation in terms of a deformed Euclidean CFT located at the threshold of eternal inflation. The partition function gives the amplitude of different geometries of the threshold surface in the no-boundary state. Its local and global behavior in dual toy models shows that the amplitude is low for surfaces which are not nearly conformal to the round three-sphere and essentially zero for surfaces with negative curvature. Based on this we conjecture that the exit from eternal inflation does not produce an infinite fractal-like multiverse, but is finite and reasonably smooth.

Factors influencing the stay-exit intention of small livestock farmers

NARCIS (Netherlands)

Carter-Leal, Luis M.; Oude-Lansink, Alfons; Saatkamp, Helmut

2018-01-01

This study analyses the factors driving the stay-exit intention of small livestock farmers located in southern Chile. Technical, economic, and social characteristics from 212 farmers were included in this study. Through an empirical probit model we identified the variables that should be considered

Exit From the High Street

DEFF Research Database (Denmark)

Bly, Sarah; Gwozdz, Wencke; Reisch, Lucia

2015-01-01

by focusing on a previously under-researched group of consumers – ‘sustainable fashion consumption pioneers’ who actively engage and shape their own discourse around the notion of sustainable fashion consumption. These pioneers actively create and communicate strategies for sustainable fashion behaviour...... of sustainable fashion including such key behaviours as purchasing fewer garments of higher quality, exiting the retail market, purchasing only second-hand fashion goods and sewing or upgrading their own clothing. Central to much of these behaviours is the notion that personal style, rather than fashion, can...... bridge the potential disconnect between sustainability and fashion while also facilitating a sense of well-being not found in traditional fashion consumption. As such, our research suggests that for these consumers sustainability is as much about reducing measurable environmental or social impacts...

Progress of the DUPIC fuel compatibility analysis (II) - thermal-hydraulics

Energy Technology Data Exchange (ETDEWEB)

Park, Joo Hwan; Choi, Hang Bok

2005-03-01

Thermal-hydraulic compatibility of the DUPIC fuel bundle with a 713 MWe Canada deuterium uranium (CANDU-6) reactor was studied by using both the single channel and sub-channel analysis methods. The single channel analysis provides the fuel channel flow rate, pressure drop, critical channel power, and the channel exit quality, which are assessed against the thermal-hydraulic design requirements of the CANDU-6 reactor. The single channel analysis by the NUCIRC code showed that the thermal-hydraulic performance of the DUPIC fuel is not different from that of the standard CANDU fuel. Regarding the local flow characteristics, the sub-channel analysis also showed that the uncertainty of the critical channel power calculation for the DUPIC fuel channel is very small. As a result, both the single and sub-channel analyses showed that the key thermal-hydraulic parameters of the DUPIC fuel channel do not deteriorate compared to the standard CANDU fuel channel.

Film techniques in radiotherapy for treatment verification, determination of patient exit dose, and detection of localization error

International Nuclear Information System (INIS)

Haus, A.G.; Marks, J.E.

1974-01-01

In patient radiation therapy, it is important to know that the diseased area is included in the treatment field and that normal anatomy is properly shielded or excluded. Since 1969, a film technique developed for imaging of the complete patient radiation exposure has been applied for treatment verification and for the detection and evaluation of localization errors that may occur during treatment. The technique basically consists of placing a film under the patient during the entire radiation exposure. This film should have proper sensitivity and contrast in the exit dose exposure range encountered in radiotherapy. In this communication, we describe how various exit doses fit the characteristic curve of the film; examples of films exposed to various exit doses; the technique for using the film to determine the spatial distribution of the absorbed exit dose; and types of errors commonly detected. Results are presented illustrating that, as the frequency of use of this film technique is increased, localization error is reduced significantly

Estimation of Surface Temperature and Heat Flux by Inverse Heat Transfer Methods Using Internal Temperatures Measured While Radiantly Heating a Carbon/Carbon Specimen up to 1920 F

Science.gov (United States)

Pizzo, Michelle; Daryabeigi, Kamran; Glass, David

2015-01-01

The ability to solve the heat conduction equation is needed when designing materials to be used on vehicles exposed to extremely high temperatures; e.g. vehicles used for atmospheric entry or hypersonic flight. When using test and flight data, computational methods such as finite difference schemes may be used to solve for both the direct heat conduction problem, i.e., solving between internal temperature measurements, and the inverse heat conduction problem, i.e., using the direct solution to march forward in space to the surface of the material to estimate both surface temperature and heat flux. The completed research first discusses the methods used in developing a computational code to solve both the direct and inverse heat transfer problems using one dimensional, centered, implicit finite volume schemes and one dimensional, centered, explicit space marching techniques. The developed code assumed the boundary conditions to be specified time varying temperatures and also considered temperature dependent thermal properties. The completed research then discusses the results of analyzing temperature data measured while radiantly heating a carbon/carbon specimen up to 1920 F. The temperature was measured using thermocouple (TC) plugs (small carbon/carbon material specimens) with four embedded TC plugs inserted into the larger carbon/carbon specimen. The purpose of analyzing the test data was to estimate the surface heat flux and temperature values from the internal temperature measurements using direct and inverse heat transfer methods, thus aiding in the thermal and structural design and analysis of high temperature vehicles.

Exit points, on plasma, of lost fast ions during NBI in TJ-II

International Nuclear Information System (INIS)

Guasp, J.

1995-09-01

The distribution of the exit points, on plasma border, for the lost fast ions during tangential balanced NBI in TJ-II helical axis Stellarator is theoretically analysed, as well for direct as for delayed losses. The link between the position of those exit points and the corresponding at birth, orbits and drifts is analysed also, it is shown that such relation is rather independent of beam energy and plasma density and is mainly related to the magnetic configuration characteristics. This study is a needed intermediate step to the analysis of impacts of those ions on the vacuum vessel of TJ-II

Monetary Policy of the Federal Reserve System from the Perspective of Exit Strategies

Directory of Open Access Journals (Sweden)

Aleksandra Nocoń

2015-07-01

Full Text Available Central banks, after the experience of the global financial crisis, are now starting the implementation of the exit strategies, which are the process of normalization of monetary policy. The pace of monetary policy normalization process depends on the market reaction to central bank's decisions and macroeconomic conditions, in which they will be implemented. The main aim of the study is to present the principles of the exit strategy of the Federal Reserve System (Fed, on the background of the changes that have occurred in the United States within the monetary policy during the global financial crisis.

SEC16 in COPII coat dynamics at ER exit sites

NARCIS (Netherlands)

Sprangers, Joep; Rabouille, Catherine

Protein export from the endoplasmic reticulum (ER), the first step in protein transport through the secretory pathway, is mediated by coatomer protein II (COPII)-coated vesicles at ER exit sites. COPII coat assembly on the ER is well understood and the conserved large hydrophilic protein Sec16

Explicit solutions for exit-only radioactive decay chains

International Nuclear Information System (INIS)

Yuan, Ding; Kernan, Warnick

2007-01-01

In this study, we extended Bateman's [Proc. Cambridge Philos. Soc. 15, 423 (1910)] original work for solving radioactive decay chains and explicitly derived analytic solutions for generic exit-only radioactive decay problems under given initial conditions. Instead of using the conventional Laplace transform for solving Bateman's equations, we used a much simpler algebraic approach. Finally, we discuss methods of breaking down certain classes of large decay chains into collections of simpler chains for easy handling

Nuclear energy - no thanks. The long way to the exit

International Nuclear Information System (INIS)

Sternstein, Wolfgang

2013-01-01

The anti-nuclear movement is one of the most successful social movements of the recent history of Germany and firmly anchored in huge parts of the population. After a struggle lasting more than forty years it has nearly reached its aims: The exit from nuclear energy and a rethinking in direction of alternative energy concepts. Decisive for the nuclear exit of the Federal government were thereby less the nuclear accidents of Harrisburg (1979), Chernobyl (1986), and Fukushima (2011) but rather the decades-long, stubborn commitment of numerous citizens as well as of citizen's initiatives. ''Nuclear energy - no thanks.'' is the analysis of the citizen's movement from Wyhl until Gorleben. The nonviolent activist and peace researcher Sternstein was there from the beginning and reports about anger and indignation that has been condensed to the social movement with political objectives. Extremely helpful are thereby the methods and strategies of nonviolent actions described by him.

2-MW plasmajet facility thermal tests of concrete

International Nuclear Information System (INIS)

Goin, K.L.

1977-07-01

A test was made in the 2-Megawatt Plasmajet Facility to obtain experimental data relative to the thermal response of concrete to incident heat flux. 14.6 cm diameter by 8.0 cm long concrete cylinders were positioned in a supersonic flow of heated nitrogen from an arc heater. The end of the concrete cylinders impacted by the flow were subjected to heat fluxes in the range of 0.13 to 0.35 kW/cm 2 . Measurements included cold wall surface heat flux and pressure distributions, surface and indepth temperatures, ablation rates, and surface emission spectrographs. The test was part of the Sandia light water reactor safety research program and complements similar tests made in the Radiant Heat Facility at heat fluxes from 0.03 to 0.12 kW/cm 2 . A description of the tests and a tabulation of test data are included

Mapping of the seasonal dynamic properties of building walls in actual periodic conditions and effects produced by solar radiation incident on the outer and inner surfaces of the wall

International Nuclear Information System (INIS)

Mazzeo, D.; Oliveti, G.; Arcuri, N.

2016-01-01

Highlights: • Dynamic thermal behaviour of building walls subjected to actual periodic loadings. • Dynamic parameters of wall in terms of energy and of heat flux are defined. • Different solar absorption coefficients and orientations of wall are considered. • On the internal surface is present or absent a shortwave radiant field. • Seasonal thermal characteristics for different plant operating regime are provided. - Abstract: In this work, the dynamic characteristics of the external walls of air-conditioned buildings subject to the joint action of periodic non-sinusoidal external and internal loadings are determined. The dynamic parameters used are the energy decrement factor, which is evaluated by means of the fluctuating heat flux in a semi-period exiting and entering the wall, the decrement factor of the maximum peak and minimum peak of the heat flux in a period and the relative time lags. The fluctuating heat flux in the wall in steady periodic regime conditions is determined with an analytical model obtained by resolving the equivalent electrical circuit. The preceding parameters are used for a study of the influence of solar radiation on the dynamic characteristics of the walls in summer and winter air-conditioning. Solar radiation is considered as operating on the external surface and on the internal surface due to the presence in the indoor environments of a shortwave radiant field. The absorbed solar heat flux by the external surface varies, modifying the solar absorption coefficient and wall orientation. Indoors, we considered a continuous operating regime of the plant and a regime with nocturnal attenuation. The results obtained, relating to 1152 different boundary conditions, were used for the construction of maps of dynamic characteristics, different on variation of the plant functioning regime and of the shortwave radiant load on the internal surface. The maps show the dependence of the decrement factors and of the time lags on variation of

Direct evaluation of reflector effects on radiant flux from InGaN-based light-emitting diodes

Science.gov (United States)

Masui, Hisashi; Fellows, Natalie N.; Sato, Hitoshi; Asamizu, Hirokuni; Nakamura, Shuji; Denbaars, Steven P.

2007-08-01

A metal layer formed on the backside of InGaN/sapphire-based light-emitting diodes deteriorates the inherent optical power output. An experimental approach of a suspended die is employed to study the effects of such metal layers via a direct comparison in radiant flux from a discrete die with and without a reflector. A sphere package that employs no reflector is proposed and fabricated. Light extraction of the sphere design is discussed; a light source in the sphere package would not have to be either an ideal point or placed at the center of the sphere, due to a finite critical angle at the sphere/air interface.

The role of clothing in thermal comfort: how people dress in a temperate and humid climate in Brazil

Directory of Open Access Journals (Sweden)

Renata De Vecchi

Full Text Available Abstract Thermal insulation from clothing is one of the most important input variables used to predict the thermal comfort of a building's occupants. This paper investigates the clothing pattern in buildings with different configurations located in a temperate and humid climate in Brazil. Occupants of two kinds of buildings (three offices and two university classrooms assessed their thermal environment through 'right-here-right-now' questionnaires, while at the same time indoor climatic measurements were carried out in situ (air temperature and radiant temperature, air speed and humidity. A total of 5,036 votes from 1,161 occupants were collected. Results suggest that the clothing values adopted by occupants inside buildings were influenced by: 1 climate and seasons of the year; 2 different configurations and indoor thermal conditions; and 3 occupants' age and gender. Significant intergenerational and gender differences were found, which might be explained by differences in metabolic rates and fashion. The results also indicate that there is a great opportunity to exceed the clothing interval of the thermal comfort zones proposed by international standards such as ASHRAE 55 (2013 - 0.5 to 1.0 clo - and thereby save energy from cooling and heating systems, without compromising the occupants' indoor thermal comfort.

Improvement of life and NO{sub x} emission of radiant tube heating system by elastic-plastic creep analysis; Dansosei kuripu kaiseki ni yoru hosha dennetsukan kanetsu shisutemu no jumyo to NO{sub x} haishutsuryo no kaizen

Energy Technology Data Exchange (ETDEWEB)

Nakagawa, Tsuguhiko; Nuta, Kunihiro [Kawasaki Steel Corp., Okayama, (Japan). Mizushima Warks

1999-03-10

The radiant tube heating system has been widely applied to the furnaces which require isolation of the heating atmosphere from the combustion atmosphere. However, the conventional system has a short life and it is difficult to reduce NO{sub x} emission when it is used at a high furnace temperature under high combustion load, because the fuel is burned in a small space. In order to solve this problem, we have studied the cause of radiant tube life depends on the uniformity of the temperature distribution along the radiant tube. We have developed a new burner using a two-stage combustion method with exhaust gas self-recirculation. As a result, the file of the new system has been increased by a factor of two or more, and NO{sub x} emission has been reduced by 20 % from previous levels. This paper presents an outline of the elastic-plastic creep analysis and the new burner, and describes the effect of its use on system life. (author)

10 CFR 431.204 - Uniform test method for the measurement of energy consumption of illuminated exit signs.

Science.gov (United States)

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false Uniform test method for the measurement of energy consumption of illuminated exit signs. 431.204 Section 431.204 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION... Procedures § 431.204 Uniform test method for the measurement of energy consumption of illuminated exit signs...

Ramp Metering Influence on Freeway Operational Safety near On-ramp Exits

Directory of Open Access Journals (Sweden)

Chiu Liu, PhD, PE, PTOE

2013-06-01

Full Text Available Ramp metering has been widely installed in urban areas where congestion on a freeway or an expressway may occur recurrently during weekday peak periods to enhance mainline throughput and reduce system-wide delay. These operational benefits may also help reduce vehicular emissions and improve air quality in urban areas. However, the impact on traffic safety due to ramp metering hasn't been explored in details before. Supported by physical understanding and arguments, we characterize the ramp metering influence on freeway safety by examining vehicular collisions near on-ramp exits within the ramp meter operating hours before and after the activation of the ramp metering. Collisions for a sample of 19 operating ramp meters along several freeways in northern California were collected and organized to show that ramp metering can help reduce freeway collisions at the vicinity of on-ramp exits. It was found that the average reductions on freeway collisions in the vicinity of an on-ramp exit are around 36%. Although most of the reduced collisions belong to the property damage only category, a 36% reduction shows the significant safety benefit of ramp metering. The traffic congestion induced by each collision, especially during peak hours when ramp metering is in operation, could last for an hour or two. Consequently, ramp metering must be contributing to the reduction of non-recurrent congestion in addition to mitigating recurrent congestion, which is better documented. This study strongly supports the implementation of ramp metering in California.

Bayesian Framework Approach for Prognostic Studies in Electrolytic Capacitor under Thermal Overstress Conditions

Science.gov (United States)

2012-09-01

make end of life ( EOL ) and remaining useful life (RUL) estimations. Model-based prognostics approaches perform these tasks with the help of first...in parameters Degradation Modeling Parameter estimation Prediction Thermal / Electrical Stress Experimental Data State Space model RUL EOL ...distribution at given single time point kP , and use this for multi-step predictions to EOL . There are several methods which exits for selecting the sigma

TomoTherapy MLC verification using exit detector data

Energy Technology Data Exchange (ETDEWEB)

Chen Quan; Westerly, David; Fang Zhenyu; Sheng, Ke; Chen Yu [TomoTherapy Inc., 1240 Deming Way, Madison, Wisconsin 53717 (United States); Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States); Xinghua Cancer Hospital, Xinghua, Jiangsu 225700 (China); Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, California 90095 (United States); TomoTherapy Inc., 1240 Deming Way, Madison, Wisconsin 53717 (United States)

2012-01-15

Purpose: Treatment delivery verification (DV) is important in the field of intensity modulated radiation therapy (IMRT). While IMRT and image guided radiation therapy (IGRT), allow us to create more conformal plans and enables the use of tighter margins, an erroneously executed plan can have detrimental effects on the treatment outcome. The purpose of this study is to develop a DV technique to verify TomoTherapy's multileaf collimator (MLC) using the onboard mega-voltage CT detectors. Methods: The proposed DV method uses temporal changes in the MVCT detector signal to predict actual leaf open times delivered on the treatment machine. Penumbra and scattered radiation effects may produce confounding results when determining leaf open times from the raw detector data. To reduce the impact of the effects, an iterative, Richardson-Lucy (R-L) deconvolution algorithm is applied. Optical sensors installed on each MLC leaf are used to verify the accuracy of the DV technique. The robustness of the DV technique is examined by introducing different attenuation materials in the beam. Additionally, the DV technique has been used to investigate several clinical plans which failed to pass delivery quality assurance (DQA) and was successful in identifying MLC timing discrepancies as the root cause. Results: The leaf open time extracted from the exit detector showed good agreement with the optical sensors under a variety of conditions. Detector-measured leaf open times agreed with optical sensor data to within 0.2 ms, and 99% of the results agreed within 8.5 ms. These results changed little when attenuation was added in the beam. For the clinical plans failing DQA, the dose calculated from reconstructed leaf open times played an instrumental role in discovering the root-cause of the problem. Throughout the retrospective study, it is found that the reconstructed dose always agrees with measured doses to within 1%. Conclusions: The exit detectors in the TomoTherapy treatment

TomoTherapy MLC verification using exit detector data

International Nuclear Information System (INIS)

Chen Quan; Westerly, David; Fang Zhenyu; Sheng, Ke; Chen Yu

2012-01-01

Purpose: Treatment delivery verification (DV) is important in the field of intensity modulated radiation therapy (IMRT). While IMRT and image guided radiation therapy (IGRT), allow us to create more conformal plans and enables the use of tighter margins, an erroneously executed plan can have detrimental effects on the treatment outcome. The purpose of this study is to develop a DV technique to verify TomoTherapy's multileaf collimator (MLC) using the onboard mega-voltage CT detectors. Methods: The proposed DV method uses temporal changes in the MVCT detector signal to predict actual leaf open times delivered on the treatment machine. Penumbra and scattered radiation effects may produce confounding results when determining leaf open times from the raw detector data. To reduce the impact of the effects, an iterative, Richardson-Lucy (R-L) deconvolution algorithm is applied. Optical sensors installed on each MLC leaf are used to verify the accuracy of the DV technique. The robustness of the DV technique is examined by introducing different attenuation materials in the beam. Additionally, the DV technique has been used to investigate several clinical plans which failed to pass delivery quality assurance (DQA) and was successful in identifying MLC timing discrepancies as the root cause. Results: The leaf open time extracted from the exit detector showed good agreement with the optical sensors under a variety of conditions. Detector-measured leaf open times agreed with optical sensor data to within 0.2 ms, and 99% of the results agreed within 8.5 ms. These results changed little when attenuation was added in the beam. For the clinical plans failing DQA, the dose calculated from reconstructed leaf open times played an instrumental role in discovering the root-cause of the problem. Throughout the retrospective study, it is found that the reconstructed dose always agrees with measured doses to within 1%. Conclusions: The exit detectors in the TomoTherapy treatment systems

A study on the impulse wave discharged from the exit of a right-angle pipe bend

International Nuclear Information System (INIS)

Lee, D. H.; Hur, S. C.; Kweon, Y. H.; Kim, H. D.

2001-01-01

The current study addresses experimental and computational work of impulse wave discharged from the exit of two kinds of right-angle pipe bends, which are attached to the open end of a simple shock tube. The weak normal shock wave with its magnitude of Mach number from 1.02 to 1.20 is employed to obtain the impulse wave propagating outside the exit of the pipe bends. A Schlieren optical system visualizes the impulse wave discharged from the exit of the pipe bends at an instant. The experimental data of the magnitude of the impulse wave and its propagating directivity are analyzed to characterize the impulse waves discharged from the exit of the pipe bends and compared with those discharged from a straight pipe. Computational results well predict the experimented dynamic behaviors of the impulse wave. The results obtained show that a right-angle miter bend considerably reduces the magnitude of the impulse wave and its directivity toward to the pipe axis, compared with the straight pipe and right-angle smooth bend. It is believed that the right-angle miter bend pipe can play a role of a passive control against the impulse wave

An Eclectic Approach to Loyalty-Promoting Instruments in Corporate Law: Revisiting Hirschman's Model of Exit, Voice, and Loyalty

NARCIS (Netherlands)

A.A. Bootsma (Bart)

2013-01-01

markdownabstract__Abstract__ This essay analyses the shareholder role in corporate governance in terms of Albert Hirschman's Exit, Voice, and Loyalty. The term 'exit' is embedded in a law & economics framework, while 'voice' relates to a corporate constitutional framework. The essay takes an

Effect of 17 x 17 fuel assembly geometry on interchannel thermal mixing

International Nuclear Information System (INIS)

Motley, F.E.; Wenzell, A.H.; Cadek, F.F.

1975-01-01

A test to determine the value of the thermal diffusion coefficient (TDC) in the 17 x 17 fuel assembly geometry was conducted. The test section was a 5 x 5 rod bundle with a radial power difference of 4.5 to 1. The rod OD and pitch are identical to the 17 x 17 fuel assembly, as is the mixing vane grid design. The value of thermal diffusion coefficient (TDC) was determined by matching the experimental exit enthalpy distribution to that predicted by the THINC computer code. The mean value of TDC for the 17 x 17 fuel assembly geometry is TDC = .059. 6 references

Exit points, on plasma, of lost fast ions during NBI in TJ-II

International Nuclear Information System (INIS)

Guasp, J.

1995-01-01

The distribution of the exit points, on plasma border, for the lost fast ions during tangential balanced NBI in TJ-II helical axis Stellarator is theoretically analysed, as well for direct as for delayed losses. The link between, the position of those exit points and the corresponding at birth, orbits and drifts is analysed also. It is shown that such relation is rather independent of beam energy and plasma density and is mainly related to the magnetic configuration characteristics. This study is a needed intermediate step to the analysis of impacts of those ions on the vacuum vessel of TJ-II. (Author) 2 refs

A Study on the Design of PM Exited Transverse Flux Linear Motor for Ropeless Elevator

Energy Technology Data Exchange (ETDEWEB)

Kang, Do Hyun; Bang, Deok Je; Kim, Jong Moo; Jeong, Yeon Ho [Korea Electrotechnology Research Institute (Korea); Kim, Moon Hwan [Silla University (Korea)

2000-03-01

The topological investigations regarding magnetic circuit geometry and winding form of the transverse flux machine have brought up a variety of constructable arrangements with different features for several types of application[1, 2]. Here with, a novel PM-exited linear motor with inner mover, based on the transverse flux configuration leads to a considerable increase in power density for moving part. In this study we designed PM-exited transverse flux linear motor for ropeless elevator, whose output power density is higher and weight is lighter than conventional linear synchronous motors, When the designed motor in this study is applied to ropeless elevator, it is possible to increase power density more than 400% comparing with PM exited linear synchronous motor. The result of this study can be utilized for ropeless elevator or gearless direct linear moving system with high output[3]. (author). 8 refs., 9 figs., 4 tabs.

Educational Inequalities in Exit from Paid Employment among Dutch Workers: The Influence of Health, Lifestyle and Work.

Science.gov (United States)

Robroek, Suzan J W; Rongen, Anne; Arts, Coos H; Otten, Ferdy W H; Burdorf, Alex; Schuring, Merel

2015-01-01

Individuals with lower socioeconomic status are at increased risk of involuntary exit from paid employment. To give sound advice for primary prevention in the workforce, insight is needed into the role of mediating factors between socioeconomic status and labour force participation. Therefore, it is aimed to investigate the influence of health status, lifestyle-related factors and work characteristics on educational differences in exit from paid employment. 14,708 Dutch employees participated in a ten-year follow-up study during 1999-2008. At baseline, education, self-perceived health, lifestyle (smoking, alcohol, sports, BMI) and psychosocial (demands, control, rewards) and physical work characteristics were measured by questionnaire. Employment status was ascertained monthly based on tax records. The relation between education, health, lifestyle, work-characteristics and exit from paid employment through disability benefits, unemployment, early retirement and economic inactivity was investigated by competing risks regression analyses. The mediating effects of these factors on educational differences in exit from paid employment were tested using a stepwise approach. Lower educated workers were more likely to exit paid employment through disability benefits (SHR:1.84), unemployment (SHR:1.74), and economic inactivity (SHR:1.53) but not due to early retirement (SHR:0.92). Poor or moderate health, an unhealthy lifestyle, and unfavourable work characteristics were associated with disability benefits and unemployment, and an unhealthy lifestyle with economic inactivity. Educational differences in disability benefits were explained for 40% by health, 31% by lifestyle, and 12% by work characteristics. For economic inactivity and unemployment, up to 14% and 21% of the educational differences could be explained, particularly by lifestyle-related factors. There are educational differences in exit from paid employment, which are partly mediated by health, lifestyle and work

Construction of an easy-to-use CRISPR-Cas9 system by patching a newly designed EXIT circuit.

Science.gov (United States)

Tang, Qiang; Lou, Chunbo; Liu, Shuang-Jiang

2017-01-01

Plasmid-borne genetic editing tools, including the widely used CRISPR-Cas9 system, have greatly facilitated bacterial programming to obtain novel functionalities. However, the lack of effective post-editing plasmid elimination methods impedes follow-up genetic manipulation or application. Conventional strategies including exposure to physical and chemical treatments, or exploiting temperature-sensitive replication origins have several drawbacks (e.g., they are limited for efficiency and are time-consuming). Therefore, the demand is apparent for easy and rapid elimination of the tool plasmids from their bacterial hosts after genetic manipulation. To bridge this gap, we designed a novel EXIT circuit with the homing endonuclease, which can be exploited for rapid and efficient elimination of various plasmids with diverse replication origins. As a proof of concept, we validated the EXIT circuit in Escherichia coli by harnessing homing endonuclease I- Sce I and its cleavage site. When integrated into multiple plasmids with different origins, the EXIT circuit allowed them to be eliminated from the host cells, simultaneously. By combining the widely used plasmid-borne CRISPR-Cas9 system and the EXIT circuit, we constructed an easy-to-use CRISPR-Cas9 system that eliminated the Cas9- and the single-guide RNA (sgRNA)-encoding plasmids in one-step. Within 3 days, we successfully constructed an atrazine-degrading E. coli strain, thus further demonstrating the advantage of this new CRISPR-Cas9 system for bacterial genome editing. Our novel EXIT circuit, which exploits the homing endonuclease I- Sce I, enables plasmid(s) with different replication origins to be eliminated from their host cells rapidly and efficiently. We also developed an easy-to-use CRISPR-Cas9 system with the EXIT circuit, and this new system can be widely applied to bacterial genome editing.

Infrared radiation

International Nuclear Information System (INIS)

Moss, C.E.; Ellis, R.J.; Murray, W.E.; Parr, W.H.

1989-01-01

All people are exposed to IR radiation from sunlight, artificial light and radiant heating. Exposures to IR are quantified by irradiance and radiant exposure to characterize biological effects on the skin and cornea. However, near-IR exposure to the retina requires knowledge of the radiance of the IR source. With most IR sources in everyday use the health risks are considered minimal; only in certain high radiant work environments are individuals exposed to excessive levels. The interaction of IR radiation with biological tissues is mainly thermal. IR radiation may augment the biological response to other agents. The major health hazards are thermal injury to the eye and skin, including corneal burns from far-IR, heat stress, and retinal and lenticular injury from near-IR radiation. 59 refs, 13 figs, 2 tabs

Ceramics and healthy heating and cooling systems: thermal ceramic panels in buildings. Conditions of comfort and energy demand versus convective systems

Directory of Open Access Journals (Sweden)

V. Echarri Iribarren

2016-12-01

Full Text Available Porcelain stoneware is a widely used building material. In recent years, its range of uses has expanded to encompass a new spectrum of innovative and inventive applications in architecture. In this research, we analysed the patented Thermal Ceramic Panel. This consists of a thin porcelain stoneware panel that incorporates a capillary system of polypropylene tubes measuring 3.5 mm in diameter embedded in a conductive ceramic interface. The system works with hot or cold water, producing healthy heating and cooling by means of radiant surfaces. Following an initial prototype test in which panels were placed on the walls of an office, we conducted simulations at the University of Alicante Museum using wall, ceiling and baffle panels, having previously monitored the state of the building. Thermal behaviour parameters were analysed and compared with those of other standard finishing materials, obtaining results for thermal comfort and energy savings in comparison with all-air systems.

Embracing the Exit: Assessment, Trust, and the Teaching of Writing

Science.gov (United States)

Eng, Joseph

2006-01-01

Historically, the Composition Program at Eastern Washington University (EWU), a comprehensive university in Cheney, WA, required a single essay sample from each composition student as the final exit exam; in practice, a student passed or failed the course based on an in-class argumentative essay, written in three consecutive class periods. Such a…

Calculation of midplane dose for total body irradiation from entrance and exit dose MOSFET measurements.

Science.gov (United States)

Satory, P R

2012-03-01

This work is the development of a MOSFET based surface in vivo dosimetry system for total body irradiation patients treated with bilateral extended SSD beams using PMMA missing tissue compensators adjacent to the patient. An empirical formula to calculate midplane dose from MOSFET measured entrance and exit doses has been derived. The dependency of surface dose on the air-gap between the spoiler and the surface was investigated by suspending a spoiler above a water phantom, and taking percentage depth dose measurements (PDD). Exit and entrances doses were measured with MOSFETs in conjunction with midplane doses measured with an ion chamber. The entrance and exit doses were combined using an exponential attenuation formula to give an estimate of midplane dose and were compared to the midplane ion chamber measurement for a range of phantom thicknesses. Having a maximum PDD at the surface simplifies the prediction of midplane dose, which is achieved by ensuring that the air gap between the compensator and the surface is less than 10 cm. The comparison of estimated midplane dose and measured midplane dose showed no dependence on phantom thickness and an average correction factor of 0.88 was found. If the missing tissue compensators are kept within 10 cm of the patient then MOSFET measurements of entrance and exit dose can predict the midplane dose for the patient.

Effects of Urban Configuration on Human Thermal Conditions in a Typical Tropical African Coastal City

Directory of Open Access Journals (Sweden)

Emmanuel Lubango Ndetto

2013-01-01

Full Text Available A long-term simulation of urban climate was done using the easily available long-term meteorological data from a nearby synoptic station in a tropical coastal city of Dar es Salaam, Tanzania. The study aimed at determining the effects of buildings’ height and street orientations on human thermal conditions at pedestrian level. The urban configuration was represented by a typical urban street and a small urban park near the seaside. The simulations were conducted in the microscale applied climate model of RayMan, and results were interpreted in terms of the thermal comfort parameters of mean radiant (Tmrt and physiologically equivalent (PET temperatures. PET values, high as 34°C, are observed to prevail during the afternoons especially in the east-west oriented streets, and buildings’ height of 5 m has less effect on the thermal comfort. The optimal reduction of Tmrt and PET values for pedestrians was observed on the nearly north-south reoriented streets and with increased buildings’ height especially close to 100 m. Likewise, buildings close to the park enhance comfort conditions in the park through additional shadow. The study provides design implications and management of open spaces like urban parks in cities for the sake of improving thermal comfort conditions for pedestrians.

An optimization method for the distance between exits of buildings considering uncertainties based on arbitrary polynomial chaos expansion

NARCIS (Netherlands)

Xie, Qimiao; Wang, Jinhui; Lu, Shouxiang; Hensen, J.L.M.

2016-01-01

The distance between exits is an important design parameter in fire safety design of buildings. In order to find the optimal distance between exits under uncertainties with a low computational cost, the surrogate model (i.e. approximation model) of evacuation time is constructed by the arbitrary

Development and demonstration of a gas-fired recuperative confined radiant burner (deliverable 42/43). Final report

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-06-01

The objective of the project was to develop and demonstrate an innovative, efficient, low-pollutant, recuperative gas-fired IR-system (infrared radiation) for industrial processes (hereafter referred to as the CONRAD-system). The CONRAD-system is confined, so flue gases from the combustion can be kept separated from the product. The gas/air mixture to the burner is preheated by means of the flue gas, which increases the radiant efficiency of the CONRAD-system significantly over traditional gas-fired IR burners. During the first phase of the project, the CONRAD-system was designed and developed. The conducted work included a survey on suitable burner materials, modelling of the burner system, basic design of burner construction, control etc., experimental characterisation of several preprototypes and detailed design of the internal heat exchanger in the burner. The result is a cost effective burner system with a documented radiant efficiency up to 66% and low emissions (NO{sub x} and CO) all in accordance with the criteria of success set up at the start of the project. In the second phase of the project, the burner system was established and tested in laboratory and in four selected industrial applications: 1) Drying of coatings on sand cores in the automotive industry. 2) Baking of bread/cake. 3) General purpose painting/powder curing process 4. Curing of powder paint on wood components. The results from the preliminary tests Overe used to optimise the CONRAD-system, before it was applied in the industrial processes and demonstrated. However, the optimised burners manufactured for demonstration suffered from different 'infant failures', which made the installation in an industrial environment very cumbersome, and even impossible in the food industry and the automotive industry. In the latter cases realistic laboratory tests Overe carried out and the established know how reported for use when the burner problems are overcome.(au)

An entry and exit model on the energy-saving investment strategy with real options

International Nuclear Information System (INIS)

Lin, Tyrone T.; Huang, S.-L.

2010-01-01

This paper presents an improved decision model based on the real options approach presented by for the firms that have not yet established energy-saving equipment under the entry and exit strategies. Furthermore, the proposed model takes account of the inevitable equipment renewal and the occurrence of unexpected events under the Poisson jump process. The timing for terminating an investment when continuous operations of that business are unprofitable is also explored to realize the optimal timing of implementing the energy-saving strategy. The future discounted benefit B follows the geometric Brownian motion with the Poisson jump process and the replacement of investment equipment. A numerical analysis is followed by a sensitivity study of various parameters to better realize their impacts on the entry and exit thresholds. The results show that for the jump case, the higher probability of occurrence of unfavorable events will result in a higher entry threshold and lower exit threshold. Investors are forced to request higher benefit thresholds to cover the higher probability of losses brought by unfavorable events.

Which consequences for the USA of its exit from the Paris agreement? An economic, commercial and geopolitical view

International Nuclear Information System (INIS)

Hache, Emmanuel; Bourcet, Clemence; Palle, Angelique

2017-06-01

The authors discuss economic impacts which its exit from the Paris agreement may have on the US at the medium and long terms, and also the possible geopolitical reconfigurations which may result from this exit at the international level. Possible economic impacts are discussed in terms of loss of competitiveness, of image and of leadership in the international innovation dynamics. The authors also notice and comment that this exit process has already started in January 2017 with the exit form the Transpacific Partnership Treaty. They question the possible emergence of new leaders for international climatic issues, and discuss the consequences of this loss of political and moral influence of the US, and of China be this leader. The authors comment the domestic situation for the US in terms of political debate between Democrats and Republicans, but also by considering the fact that the environment policy is a power issue between local and federal authorities in the US

Timely Endocytosis of Cytokinetic Enzymes Prevents Premature Spindle Breakage during Mitotic Exit.

Directory of Open Access Journals (Sweden)

Cheen Fei Chin

2016-07-01

Full Text Available Cytokinesis requires the spatio-temporal coordination of membrane deposition and primary septum (PS formation at the division site to drive acto-myosin ring (AMR constriction. It has been demonstrated that AMR constriction invariably occurs only after the mitotic spindle disassembly. It has also been established that Chitin Synthase II (Chs2p neck localization precedes mitotic spindle disassembly during mitotic exit. As AMR constriction depends upon PS formation, the question arises as to how chitin deposition is regulated so as to prevent premature AMR constriction and mitotic spindle breakage. In this study, we propose that cells regulate the coordination between spindle disassembly and AMR constriction via timely endocytosis of cytokinetic enzymes, Chs2p, Chs3p, and Fks1p. Inhibition of endocytosis leads to over accumulation of cytokinetic enzymes during mitotic exit, which accelerates the constriction of the AMR, and causes spindle breakage that eventually could contribute to monopolar spindle formation in the subsequent round of cell division. Intriguingly, the mitotic spindle breakage observed in endocytosis mutants can be rescued either by deleting or inhibiting the activities of, CHS2, CHS3 and FKS1, which are involved in septum formation. The findings from our study highlight the importance of timely endocytosis of cytokinetic enzymes at the division site in safeguarding mitotic spindle integrity during mitotic exit.

Formation of vortex pairs with hinged rigid flaps at the nozzle exit

Science.gov (United States)

Das, Prashant; Govardhan, Raghuraman; Arakeri, Jaywant

2013-11-01

Biological flows related to aquatic propulsion using pulsed jets, or flow through the valves in a human heart, have received considerable attention in the last two decades. Both these flows are associated with starting jets that occur through biological tissue/membranes that are flexible. Motivated by these flows, we explore in the present work, the effect of passive flexibility of the nozzle exit on vortex generation from a starting jet. The starting jet is generated using a two-dimensional piston cylinder mechanism, the cross-section of the cylinder being rectangular with large aspect ratio. The fluid is pushed out of this cylinder or channel using a computer controlled piston. We introduce flexibility at the channel exit by hinging rigid flaps, which are initially parallel to the channel. The hinge used is such that it provides negligible stiffness or damping, thus allowing for the maximum opening of the flaps due to fluid forces. Using this system, we study both the flap kinematics and the vorticity dynamics downstream of the channel exit. Visualizations show large flap motions as the piston starts and this dramatically changes the vorticity distribution downstream of the flaps, with the formation of up to three different kinds of vortex pairs. This idealized configuration opens new opportunities to look at the effect of flexibility in such biological flows.

Exit Options in Corporate Finance: Liquidity versus Incentives

OpenAIRE

Aghion, Philippe; Bolton, P.; Tirole, J.

2004-01-01

This paper provides a first study of the optimal design of active monitors' exit options in a problem involving a demand for liquidity and costly monitoring of the issuer. Optimal incentives to monitor the issuer may involve restricting the monitor's right to sell her claims on the firm's cash-flow early. But the monitor will then require a liquidity premium for holding such an illiquid claim. In general, therefore, there will be a trade off between incentives and liquidity. The paper highlig...

Water Entry and Exit of Horizontal Cylinder in Free Surface Flow

International Nuclear Information System (INIS)

Hafsia, Zouhaier; Maalel, Khlifa; Mnasri, Chokri; Mohamed, Omri

2009-01-01

This paper describes two-dimensional numerical simulations of the water entry and exit of horizontal circular cylinder at constant velocity. The deformation of free surface is described by Navier-Stokes (N S) equations of incompressible and viscous fluid with additional transport equation of the volume-of-fluid (VOF). The motion of the cylinder is modeled by the associated momentum source term implemented in the Phoenicis (Parabolic Hyperbolic Or Elliptic Numerical Integration Code Series) code. The domain is discretized by a fixed Cartesian grid using a finite volume method and the cylinder is represented and cut cell method. The simulated results are compared with the numerical results of Lin (2007). This comparison shows good agreement in terms of free surface evolution for water exit and sinking. However, for water entry, the jet flow simulated by Lin is not reproduced. The free surface deformation around the cylinder in downward direction is accurately predicted

Radiant heat exchange measurements for Tore Supra

International Nuclear Information System (INIS)

Chatain, D.; Disdier, F.; Gauthier, A.; Raffin, M.; Renaud, M.

1984-03-01

In order to minimize the energy consumption of the low temperature cryogenic system connected to the superconducting magnet of TORE-SUPRA, heat exchange from thermal radiation between the vacuum vessels and the thermal shields has been studied. Accordingly large scale cold and hot walls of T.S. have been simulated in a model with reduced dimensions. In this model, the experiment consists in the measurement of the thermal radiated power between two concentric cylindrical surfaces of stainless steel under vacuum conditions. The temperature of the external cylinder was kept constant at 80 K. The internal cylinder was bakeable up to 250 0 C. Various surface treatments were applied on the two cylinders (mechanical polishing and metal deposition of Al, Ag, Ni) [fr

Sidewalk Landscape Structure and Thermal Conditions for Child and Adult Pedestrians

Science.gov (United States)

Kim, Young-Jae; Lee, Chanam; Kim, Jun-Hyun

2018-01-01

Walking is being promoted for health and transportation purposes across all climatic regions in the US and beyond. Despite this, an uncomfortable microclimate condition along sidewalks is one of the major deterrents of walking, and more empirical research is needed to determine the risks of heat exposure to pedestrians while walking. This study examined the effect of street trees and grass along sidewalks on air temperatures. A series of thermal images were taken at the average heights of adults and children in the US to objectively measure the air temperatures of 10 sidewalk segments in College Station, TX, USA. After controlling the other key physical environmental conditions, sidewalks with more trees or wider grass buffer areas had lower air temperatures than those with less vegetation. Children were exposed to higher temperatures due to the greater exposure or proximity to the pavement surface, which tends to have higher radiant heat. Multivariate regression analysis suggested that the configuration of trees and grass buffers along the sidewalks helped to promote pleasant thermal conditions and reduced the differences in ambient air temperatures measured at child and adult heights. This study suggests that street trees and vegetated ground help reduce the air temperatures, leading to more thermally comfortable environments for both child and adult pedestrians in warm climates. The thermal implications of street landscape require further attention by researchers and policy makers that are interested in promoting outdoor walking. PMID:29346312

Field tests on human tolerance to (LNG) fire radiant heat exposure, and attenuation effects of clothing and other objects

International Nuclear Information System (INIS)

Raj, Phani K.

2008-01-01

A series of field tests exposing mannequins clothed with civilian clothing to a 3 m x 3 m square liquefied natural gas (LNG) pool fire was conducted. Both single layer clothing and double layer clothing were used. The radiant heat flux incident outside the clothing and incident on the skin covered by clothing were measured using wide-angle radiometers, for durations of 100-200 s (per test). The levels of heat flux incident on the clothing were close to 5 kW/m 2 . The magnitude of the radiant heat attenuation factor (AF) across the thickness was determined. AF varies between 2 and higher for cotton and polyester clothing (thickness 0.286-1.347 mm); AF value of 6 was measured for 1.347 mm thickness. Single sheet newspaper held about 5 cm in front of mannequins and exposed to incident flux of 5 kW/m 2 resulted in AF of 5, and AF of 8 with double sheets. AF decreases linearly with increasing heat flux values and linearly increases with thickness. The author exposed himself, in normal civilian clothing (of full sleeve cotton/polyester shirt and jean pants), to radiant heat from a LNG fire. The exposure was for several tens of seconds to heat flux levels ranging from 3.5 kW/m 2 to 5 + kW/m 2 (exposure times from 25 s to 97 s at average heat flux values in the 4 kW/m 2 and 5 kW/m 2 range). Occasionally, he was exposed to (as high as) 7 kW/m 2 for durations of several seconds. He did not suffer any unbearable or even severe pain nor did he experience blisters or burns or any other injury on the unprotected skin of his body. The incident heat fluxes on the author were measured by a hand-held radiometer (with digital display) as well as by strapped on wide-angle radiometers connected to a computer. He could withstand the US regulatory criterion of 5 kW/m 2 (for 30 s) without suffering any damage or burns. Temperature measured on author's skin covered by clothing did not rise above the normal body temperature even after 200 s of exposure to 4 kW/m 2 average heat flux

Some Features of Aerodynamics of Cyclonic Chamber with Free Exit

Directory of Open Access Journals (Sweden)

A. N. Orekhov

2007-01-01

Full Text Available The paper cites results of an experimental research in aerodynamics of a cyclonic chamber with a free exit that has a large relative length. Distributions of aerodynamic stream characteristics depending on geometry of working volume of the cyclonic chamber are given in the paper. Calculative dependences are proposed in the paper.

Diving, Jumping and Drinking: instabilities during water entry and exit

Science.gov (United States)

Jung, Sunghwan

2017-11-01

All organisms interact with fluids in one way or another, and some have presumably adapted their behaviors or features in response to fluid-mechanical forces. Particularly, fluid forces are of great importance when organisms or their body parts move in and out of water. In this talk, I will discuss three problems in which fluid mechanics principles affect form and function of animals. The first problem is how several seabirds (e.g. Gannets and Boobies) dive into water at up to 24 m/s without any injuries. This study examines the effects of their beak shape and dense feathers during water entry to reduce or spread the impact force on the body. The second problem is how animals jump out of water, from plankton to whales. Some aquatic animals generate enough force to exit the water surface as an effective method of capturing prey or escaping from predators. Finally, I will discuss about lapping animals (e.g. dog and cat) as a combined water entry and exit. During the tongue-lapping, associated fluid forces and pinch-off instability will be discussed.

Steam exit flow design for aft cavities of an airfoil

Science.gov (United States)

Storey, James Michael; Tesh, Stephen William

2002-01-01

Turbine stator vane segments have inner and outer walls with vanes extending therebetween. The inner and outer walls have impingement plates. Steam flowing into the outer wall passes through the impingement plate for impingement cooling of the outer wall surface. The spent impingement steam flows into cavities of the vane having inserts for impingement cooling the walls of the vane. The steam passes into the inner wall and through the impingement plate for impingement cooling of the inner wall surface and for return through return cavities having inserts for impingement cooling of the vane surfaces. A skirt or flange structure is provided for shielding the steam cooling impingement holes adjacent the inner wall aerofoil fillet region of the nozzle from the steam flow exiting the aft nozzle cavities. Moreover, the gap between the flash rib boss and the cavity insert is controlled to minimize the flow of post impingement cooling media therebetween. This substantially confines outflow to that exiting via the return channels, thus furthermore minimizing flow in the vicinity of the aerofoil fillet region that may adversely affect impingement cooling thereof.

Experimental studies of thermal preparation of internal combustion engine

Science.gov (United States)

Karnaukhov, N. N.; Merdanov, Sh M.; V, Konev V.; Borodin, D. M.

2018-05-01

In conditions of autonomous functioning of road construction machines, it becomes necessary to use its internal sources. This can be done by using a heat recovery system of an internal combustion engine (ICE). For this purpose, it is proposed to use heat accumulators that accumulate heat of the internal combustion engine during the operation of the machine. Experimental studies have been carried out to evaluate the efficiency of using the proposed pre-start thermal preparation system, which combines a regular system based on liquid diesel fuel heaters and an ICE heat recovery system. As a result, the stages of operation of the preheating thermal preparation system, mathematical models and the dependence of the temperature change of the antifreeze at the exit from the internal combustion engine on the warm-up time are determined.

Longwave infrared observation of urban landscapes

Science.gov (United States)

Goward, S. N.

1981-01-01

An investigation is conducted regarding the feasibility to develop improved methods for the identification and analysis of urban landscapes on the basis of a utilization of longwave infrared observations. Attention is given to landscape thermal behavior, urban thermal properties, modeled thermal behavior of pavements and buildings, and observed urban landscape thermal emissions. The differential thermal behavior of buildings, pavements, and natural areas within urban landscapes is found to suggest that integrated multispectral solar radiant reflectance and terrestrial radiant emissions data will significantly increase potentials for analyzing urban landscapes. In particular, daytime satellite observations of the considered type should permit better identification of urban areas and an analysis of the density of buildings and pavements within urban areas. This capability should enhance the utility of satellite remote sensor data in urban applications.

An experimental study about effect of far infrared radiant ceramics on efficient methane fermentation

International Nuclear Information System (INIS)

Oda, A.; Yamazaki, M.; Oida, A.

2003-01-01

Methane fermentation, well known as one of the methods for organic wastes treatment, has been used as an energy production process in order to produce a gaseous fuel. But methane fermentation has some problems to be solved about gas production rate and volatile solids reduction efficiency. Simple methods to improve these problems are needed. In this study, we focused on far infrared radiant ceramics as a stimulating substance to activate methanogenic bacteria. Firstly, through the experiment of one batch fermentation, it was confirmed that the ceramics in the fermenter caused increase of total gas production. Next, even through the experiment of continuous fermentation, same stimulating effect was confirmed. It was considered that this effect was caused not only by a function of bio-contactor of the ceramics but also by far infrared radiation from ceramics. (author)

The Ribosomal Protein uL22 Modulates the Shape of the Protein Exit Tunnel

DEFF Research Database (Denmark)

Wekselman, Itai; Zimmerman, Ella; Davidovich, Chen

2017-01-01

Erythromycin is a clinically useful antibiotic that binds to an rRNA pocket in the ribosomal exit tunnel. Commonly, resistance to erythromycin is acquired by alterations of rRNA nucleotides that interact with the drug. Mutations in the β hairpin of ribosomal protein uL22, which is rather distal...... of the β hairpin of the mutated uL22 toward the interior of the exit tunnel, triggering a cascade of structural alterations of rRNA nucleotides that propagate to the erythromycin binding pocket. Our findings support recent studies showing that the interactions between uL22 and specific sequences within...

S-phase Synchronization Facilitates the Early Progression of Induced-Cardiomyocyte Reprogramming through Enhanced Cell-Cycle Exit.

Science.gov (United States)

Bektik, Emre; Dennis, Adrienne; Pawlowski, Gary; Zhou, Chen; Maleski, Danielle; Takahashi, Satoru; Laurita, Kenneth R; Deschênes, Isabelle; Fu, Ji-Dong

2018-05-04

Direct reprogramming of fibroblasts into induced cardiomyocytes (iCMs) holds a great promise for regenerative medicine and has been studied in several major directions. However, cell-cycle regulation, a fundamental biological process, has not been investigated during iCM-reprogramming. Here, our time-lapse imaging on iCMs, reprogrammed by Gata4, Mef2c, and Tbx5 (GMT) monocistronic retroviruses, revealed that iCM-reprogramming was majorly initiated at late-G1- or S-phase and nearly half of GMT-reprogrammed iCMs divided soon after reprogramming. iCMs exited cell cycle along the process of reprogramming with decreased percentage of 5-ethynyl-20-deoxyuridine (EdU)⁺/α-myosin heavy chain (αMHC)-GFP⁺ cells. S-phase synchronization post-GMT-infection could enhance cell-cycle exit of reprogrammed iCMs and yield more GFP high iCMs, which achieved an advanced reprogramming with more expression of cardiac genes than GFP low cells. However, S-phase synchronization did not enhance the reprogramming with a polycistronic-viral vector, in which cell-cycle exit had been accelerated. In conclusion, post-infection synchronization of S-phase facilitated the early progression of GMT-reprogramming through a mechanism of enhanced cell-cycle exit.

Association between keeping home records of catheter exit-site and incidence of peritoneal dialysis-related infections.

Science.gov (United States)

Iida, Hidekazu; Kurita, Noriaki; Fujimoto, Shino; Kamijo, Yuka; Ishibashi, Yoshitaka; Fukuma, Shingo; Fukuhara, Shunichi

2018-04-01

To prevent peritoneal dialysis (PD)-related infection, components of self-catheter care have been emphasized. However, studies on the effectiveness of home recording for the prevention of PD-related infections are limited. This study aimed to examine the association between keeping home records of catheter exit site and incidence of PD-related infections. Home record books were submitted by patients undergoing PD. The proportion of days on which exit-site home recording was carried out for 120 days (0-100%) was obtained. The patients were divided into the frequent home recording group (≥ 40.5%; median value) and the infrequent home recording group (home recording groups for PD-related infection were 1.58 (95% confidence interval [CI], 0.72-3.46) in the univariate analysis and 1.49 (95% CI, 0.65-3.42) in the multivariate analysis. The IRRs of the frequent versus infrequent home recording groups for composite of surgery to create a new exit site and removal of PD catheter were 0.55 (95% CI, 0.78-3.88) and 0.35 (95% CI, 0.06-1.99), respectively. This study could not prove that keeping home records of patients' catheter exit site is associated with a lower incidence of PD-related infections.

All rights reserved and www.bioline.org.br/ja Estimation of exit ...

African Journals Online (AJOL)

ADOWIE PERE

and www.bioline.org.br/ja. Estimation of exit temperatures in the isentropic compression of real gases. 1 ..... other thermodynamic properties can be calculated within the framework of ... of negative compressibility) has no physical significance.

Estimation of exit temperatures in the isentropic compression of real ...

African Journals Online (AJOL)

This paper presents the estimation of exit temperatures in the isentropic compression of real gases based on the Peng-Robinson equation of state and entropy balance method. The methods were applied to Ar, N2, CH4, CO2, C2H4 and C2H6. Data obtained revealed that isentropic exponent method provides useful results ...

Relationship between Amount of Exited Blood During Wet-cupping with Patient’s Individual Conditions and the Time of Doing it

Directory of Open Access Journals (Sweden)

Ghazanfari M

2017-12-01

Full Text Available Aims Wet-cupping as a therapeutic method has been recommended to be done on certain days based on authentic sources of traditional medicine in Iran. The purpose of this study was to determine the relationship between amount of exited blood during wet-cupping with patient’s individual conditions and the time it was performed. Instruments & Methods In this descriptive cross-sectional study, 391 men who were referred to a cupping center in Saveh city in the spring of 2016, were selected by simple sampling and wet-cupping in the position between the two scapula was performed. The research instrument was a questionnaire including demographic characteristics, date of reference (day, month and year, age, height, weight and amount of exited blood during the wet-cupping in gram. Data were analyzed by SPSS 16 software and using chi-square test, paired t test and one-way analysis of variance. Findings The means of age, weight and body mass index were significantly related to the mean of amount of exited blood during wet-cupping (p0.05, but the amount of exited blood was higher in people with previous history of wet-cupping than those without previous history (p<0.001. Also, in people with hypertension, the amount of exited blood was higher than other treatment groups (p<0.05. Conclusion Individual characteristics such as age, weight, body mass index, cause of referral and previous history of wet-cupping affect the amount of exited blood during wet-cupping, but the time of wet-cupping (day and month does not affect the amount of exited blood.

Helping Survivors of Human Trafficking: A Systematic Review of Exit and Postexit Interventions.

Science.gov (United States)

Dell, Nathaniel A; Maynard, Brandy R; Born, Kara R; Wagner, Elizabeth; Atkins, Bonnie; House, Whitney

2017-01-01

Human trafficking is a global problem and results in deleterious psychological, social, and physical effects on the lives of those who are trafficked; however, it is not clear how to best intervene with survivors. The purpose of this review was to synthesize the evidence of exit and postexit intervention programs for survivors of human trafficking to inform practice and research. Systematic review methods were used to search, select, and extract data from published and unpublished experimental, quasi-experimental, and preexperimental studies that assessed the effects of any exit or postexit interventions for victims of human trafficking. The authors searched eight databases, reviewed bibliographies, and conducted forward citation searches from relevant reports and prior reviews to find studies authored between 2005 and 2015. The search yielded six eligible studies that included 155 female and 6 male survivors from four countries. Interventions were diverse, with three using a trauma-informed approach. Authors measured a myriad of outcomes, including mental health, social network, community reintegration, and employment; however, the quality of most studies was poor. Evidence of effects of exit and postexit interventions is sparse, and much of the research is poorly designed and executed; however, the needs of trafficking survivors are complex and effective interventions are desperately needed. Implications for practice and research are discussed.

Thermal cracking of recycled hydrocarbon gas-mixtures for re-pyrolysis: Operational analysis of some industrial furnaces

Energy Technology Data Exchange (ETDEWEB)

Gal, T. [MOL PETCHEM Division, Tisza Chemical Works Co. Ltd. (TVK), P.O. Box 20, H-3581 Tiszaujvaros (Hungary); Lakatos, B.G. [Department of Process Engineering, University of Pannonia, P.O. Box 158, H-8200 Veszprem (Hungary)

2008-02-15

Thermal decomposition process of recycled hydrocarbon gas-mixtures in industrial furnaces is analyzed by computer simulation. The detailed kinetic and mathematical model developed was validated by using the process control laboratory cracked gas analysis of an industrially operated furnace. The effects of feed compositions and operational conditions are examined to select the favorable operating parameters and to achieve the possibly highest online operation period of the furnace. The effect of deposited coke on the lifetime of radiant coils is examined by a heat-transfer model. The simulation study confirmed that temporal variations of the feedstock composition could be harmonized well with the operating parameters of furnaces with the purpose of achieving maximum effectiveness. (author)

Radiant thinking and the use of the mind map in nurse practitioner education.

Science.gov (United States)

Spencer, Julie R; Anderson, Kelley M; Ellis, Kathryn K

2013-05-01

The concept of radiant thinking, which led to the concept of mind mapping, promotes all aspects of the brain working in synergy, with thought beginning from a central point. The mind map, which is a graphical technique to improve creative thinking and knowledge attainment, utilizes colors, images, codes, and dimensions to amplify and enhance key ideas. This technique augments the visualization of relationships and links between concepts, which aids in information acquisition, data retention, and overall comprehension. Faculty can promote students' use of the technique for brainstorming, organizing ideas, taking notes, learning collaboratively, presenting, and studying. These applications can be used in problem-based learning, developing plans of care, health promotion activities, synthesizing disease processes, and forming differential diagnoses. Mind mapping is a creative way for students to engage in a unique method of learning that can expand memory recall and help create a new environment for processing information. Copyright 2013, SLACK Incorporated.

Radiation degradation of aromatic pollutants exit in wastewater and ph dependence

CERN Document Server

Takriti, S

2002-01-01

The effect of gamma radiation on the degradation of phenol (hydroxybenzene), resorcinol (1,3 dihydroxybenzen) and hydroquinone (1,4 dihydroxybenzen) exit in waste water was investigated. The concentrations of these pollutants as well as the irradiated solution ph were studied. The results showed that the phenol is very resistance against the radiation doses comparing the other phenol compounds. Phenol was also a product of radiolysis of resorcinol and hydroquinone. On the other hand, the acid phase of the irradiation sample increased the degradation rate of pollutants. Spectrophotometer (UV-VIS) and chromatography (HPLC) were used to monitor the analysis of the radiation product solution. The results illustrated the existing of many substances such as organic alcohol, aldehyde, ketone and acidic functional groups as a final radiation products. The degradation of benzene, monochlorobenzene (CB) and 1,2 dichlorobenzene (1,2 DCB) exit in waste water by gamma irradiation was investigated. The effect of the irradi...

Thermal analysis of heat storage canisters for a solar dynamic, space power system

Science.gov (United States)

Wichner, R. P.; Solomon, A. D.; Drake, J. B.; Williams, P. T.

1988-01-01

A thermal analysis was performed of a thermal energy storage canister of a type suggested for use in a solar receiver for an orbiting Brayton cycle power system. Energy storage for the eclipse portion of the cycle is provided by the latent heat of a eutectic mixture of LiF and CaF2 contained in the canister. The chief motivation for the study is the prediction of vapor void effects on temperature profiles and the identification of possible differences between ground test data and projected behavior in microgravity. The first phase of this study is based on a two-dimensional, cylindrical coordinates model using an interim procedure for describing void behavor in 1-g and microgravity. The thermal analysis includes the effects of solidification front behavior, conduction in liquid/solid salt and canister materials, void growth and shrinkage, radiant heat transfer across the void, and convection in the melt due to Marangoni-induced flow and, in 1-g, flow due to density gradients. A number of significant differences between 1-g and o-g behavior were found. This resulted from differences in void location relative to the maximum heat flux and a significantly smaller effective conductance in 0-g due to the absence of gravity-induced convection.

In vivo dosimetry with thermoluminescent dosimeters in radiotherapy: entrance and exit doses

International Nuclear Information System (INIS)

Alves, C.; Lopes, M.C.

2000-01-01

In vivo dosimetry, by entrance and exit dose measurements, is a vital part of a radiotherapy quality assurance program. The uncertainty associated with dose delivery is internationally accepted to be within 5% or inferior depending on the tumor pathology. Thermoluminescent dosimetry is one of the dosimetric techniques used to verify the agreement between delivered and prescribed doses. Nevertheless, it requires a very accurate calibration methodology. We have used LiF chips (4.5 mm diameter and 0.8 mm thick) calibrated towards a PTW ionization chamber of 0.3 cc, in three photon energies: Co-60, 4 and 6 MeV. The TLD reader used was a Rialto 688 from NE Technology and the annealing oven the Eurotherm type 815. The calibration methodology relies on the experimental determination of individual correction factors and on a correction factor derived from a control group of dosimeters. The exit and entrance dose measurements are performed in quite different situations. To be able to achieve those two quantities with TLD, these should be independently calibrated according to the measurement conditions. Alternatively, we can use a single calibration, in entrance dose, and convert the result to the exit dose value by introducing some correction factors. These corrections are related to the different measurement depths and to the different backscattering contributions. We have proved that within an acceptable error we can perform a single calibration and adopt the correction factors which are energy and field size dependent. (author)

Effects of inlet distortion on gas turbine combustion chamber exit temperature profiles

Science.gov (United States)

Maqsood, Omar Shahzada

Damage to a nozzle guide vane or blade, caused by non-uniform temperature distributions at the combustion chamber exit, is deleterious to turbine performance and can lead to expensive and time consuming overhaul and repair. A test rig was designed and constructed for the Allison 250-C20B combustion chamber to investigate the effects of inlet air distortion on the combustion chamber's exit temperature fields. The rig made use of the engine's diffuser tubes, combustion case, combustion liner, and first stage nozzle guide vane shield. Rig operating conditions simulated engine cruise conditions, matching the quasi-non-dimensional Mach number, equivalence ratio and Sauter mean diameter. The combustion chamber was tested with an even distribution of inlet air and a 4% difference in airflow at either side. An even distribution of inlet air to the combustion chamber did not create a uniform temperature profile and varying the inlet distribution of air exacerbated the profile's non-uniformity. The design of the combustion liner promoted the formation of an oval-shaped toroidal vortex inside the chamber, creating localized hot and cool sections separated by 90° that appeared in the exhaust. Uneven inlet air distributions skewed the oval vortex, increasing the temperature of the hot section nearest the side with the most mass flow rate and decreasing the temperature of the hot section on the opposite side. Keywords: Allison 250, Combustion, Dual-Entry, Exit Temperature Profile, Gas Turbine, Pattern Factor, Reverse Flow.

Firm Size and Short-Term Dynamics in Aggregate Entry and Exit

NARCIS (Netherlands)

Manjon, M.C.

2004-01-01

Much of the research on industry dynamics focuses on the interdependence between the sectorial rates of entry and exit.This paper argues that the size of firms and the reaction-adjustment period are important conditions missed in this literature.I illustrate the effects of this omission using data

Numerical identification of blade exit angle effect on the performance for a multistage centrifugal pump impeller

Directory of Open Access Journals (Sweden)

Babayigit Osman

2015-01-01

Full Text Available Nowadays, single and multistage centrifugal pumps are widely used in industrial and mining enterprises. One of the most important components of a centrifugal pump is the impeller. The performance characteristics are related to the pump comprising the head and the overall efficiency rely a great deal on the impeller geometry. In this work, effects of blade exit angle change on hydraulic efficiency of a multi stage pump impeller are investigated via Ansys-Fluent computational fluid dynamics software for constant width impeller entrance and exit gates, blade numbers and blade thickness. Firstly, the flow volume of a centrifugal pump impeller is generated and then mesh structure is formed for the full impeller flow volume. Secondly, rotational periodic flow model are adopted in order to examine the effect of periodic flow assumption on the performance predictions. Corresponding to the available experimental data, inlet mass flow rate, outlet static pressure and rotation of impeller are taken as 0.02m3s-1, 450 kPa and 2950 rpm, respectively for the water fluid. No slip boundary condition is exposed to all solid of surface in the flow volume. The continuity and Navier-Stokes equations with the k-ε turbulence model and the standard wall functions are used. During the study, numerical analyses are conducted for the blade exit angle values of 18°, 20°, 25°, 30° and 35°. In consequence of the performed analyses, it is determined that hydraulic efficiency of the pump impeller value is changed between 81.0-84.6%. The most convenient blade exit angle that yields 84.6% hydraulic efficiency at is 18°. The obtained results show that the blade exit angle range has an impact on the centrifugal pump performance describing the pump head and the hydraulic efficiency.

Synthesis and Characterization of Fibre Reinforced Silica Aerogel Blankets for Thermal Protection

Directory of Open Access Journals (Sweden)

S. Chakraborty

2016-01-01

Full Text Available Using tetraethoxysilane (TEOS as the source of silica, fibre reinforced silica aerogels were synthesized via fast ambient pressure drying using methanol (MeOH, trimethylchlorosilane (TMCS, ammonium fluoride (NH4F, and hexane. The molar ratio of TEOS/MeOH/(COOH2/NH4F was kept constant at 1 : 38 : 3.73 × 10−5 : 0.023 and the gel was allowed to form inside the highly porous meta-aramid fibrous batting. The wet gel surface was chemically modified (silylation process using various concentrations of TMCS in hexane in the range of 1 to 20% by volume. The fibre reinforced silica aerogel blanket was obtained subsequently through atmospheric pressure drying. The aerogel blanket samples were characterized by density, thermal conductivity, hydrophobicity (contact angle, and Scanning Electron Microscopy. The radiant heat resistance of the aerogel blankets was examined and compared with nonaerogel blankets. It has been observed that, compared to the ordinary nonaerogel blankets, the aerogel blankets showed a 58% increase in the estimated burn injury time and thus ensure a much better protection from heat and fire hazards. The effect of varying the concentration of TMCS on the estimated protection time has been examined. The improved thermal stability and the superior thermal insulation of the flexible aerogel blankets lead to applications being used for occupations that involve exposure to hazards of thermal radiation.

Environmental regulations and plant exit: A logit analysis based on established panel data

Energy Technology Data Exchange (ETDEWEB)

Bioern, E; Golombek, R; Raknerud, A

1995-12-01

This publication uses a model to study the relationship between environmental regulations and plant exit. It has the main characteristics of a multinomial qualitative response model of the logit type, but also has elements of a Markov chain model. The model uses Norwegian panel data for establishments in three manufacturing sectors with high shares of units which have been under strict environmental regulations. In two of the sectors, the exit probability of non-regulated establishments is about three times higher than for regulated ones. It is also found that the probability of changing regulation status from non-regulated to regulated depends significantly on economic factors. In particular, establishments with weak profitability are the most likely to become subject to environmental regulation. 12 refs., 2 figs., 6 tabs.

Effects of street canyon design on pedestrian thermal comfort in the hot-humid area of China.

Science.gov (United States)

Zhang, Yufeng; Du, Xiaohan; Shi, Yurong

2017-08-01

The design characteristics of street canyons were investigated in Guangzhou in the hot-humid area of China, and the effects of the design factors and their interactions on pedestrian thermal comfort were studied by numerical simulations. The ENVI-met V4.0 (BASIC) model was validated by field observations and used to simulate the micrometeorological conditions and the standard effective temperature (SET) at pedestrian level of the street canyons for a typical summer day of Guangzhou. The results show that the micrometeorological parameters of mean radiant temperature (MRT) and wind speed play key roles in pedestrian thermal comfort. Street orientation has the largest contribution on SET at pedestrian level, followed by aspect ratio and greenery, while surface albedo and interactions between factors have small contributions. The street canyons oriented southeast-northwest or with a higher aspect ratio provide more shade, higher wind speed, and better thermal comfort conditions for pedestrians. Compared with the east-west-oriented street canyons, the north-south-oriented street canyons have higher MRTs and worse pedestrian thermal comfort due to their wider building spacing along the street. The effects of greenery change with the road width and the time of the day. Street canyon design is recommended to improve pedestrian thermal comfort. This study provides a better understanding of the effects of street canyon design on pedestrian thermal comfort and is a useful guide on urban design for the hot-humid area of China.

Retrospectively assessed physical work environment during working life and risk of sickness absence and labour market exit among older workers

DEFF Research Database (Denmark)

Sundstrup, Emil; Hansen, Åse Marie; Mortensen, Erik Lykke

2018-01-01

OBJECTIVE: To determine the prospective association between retrospectively assessed physical work environment during working life and prospectively assessed sickness absence and labour market exit among older workers. METHODS: Using Cox regression analyses we estimated the 4-year to 6-year...... and exposure to several factors in the physical work environment, especially heavy lifting, were important for labour market exit and sickness absence. This study underscores the importance of reducing physical work exposures throughout the working life course for preventing sickness absence and premature exit...... from the labour market....

Quantifying groundwater dependency of riparian surface hydrologic features using the exit gradient

Science.gov (United States)

This study examines groundwater exit gradients as a way to quantify groundwater interactions with surface water. We calibrated high resolution groundwater models for the basin fill sediments in the lower Calapooia watershed, Oregon, using data collected between 1928--2000. The e...

The relationship between substance use and exit security on psychiatric wards

NARCIS (Netherlands)

Simpson, A.; Bowers, L.; Allan, T.; Haglund, K.; Muir-Cochrane, E.; Nijman, H.L.I.; Merwe, M. van der

2011-01-01

Aim.  In this paper we report on the rates of drug/alcohol use on acute psychiatric wards in relation to levels and intensity of exit security measures. Background.  Many inpatient wards have become permanently locked, with staff concerned about the risk of patients leaving the ward and harming

Estimates of the first Dirichlet eigenvalue from exit time moment spectra

DEFF Research Database (Denmark)

Hurtado, Ana; Markvorsen, Steen; Palmer, Vicente

2013-01-01

We compute the first Dirichlet eigenvalue of a geodesic ball in a rotationally symmetric model space in terms of the moment spectrum for the Brownian motion exit times from the ball. This expression implies an estimate as exact as you want for the first Dirichlet eigenvalue of a geodesic ball...

Everolimus for Advanced Pancreatic Neuroendocrine Tumours: A Subgroup Analysis Evaluating Japanese Patients in the RADIANT-3 Trial

Science.gov (United States)

Ito, Tetsuhide; Okusaka, Takuji; Ikeda, Masafumi; Igarashi, Hisato; Morizane, Chigusa; Nakachi, Kohei; Tajima, Takeshi; Kasuga, Akio; Fujita, Yoshie; Furuse, Junji

2012-01-01

Objective Everolimus, an inhibitor of the mammalian target of rapamycin, has recently demonstrated efficacy and safety in a Phase III, double-blind, randomized trial (RADIANT-3) in 410 patients with low- or intermediate-grade advanced pancreatic neuroendocrine tumours. Everolimus 10 mg/day provided a 2.4-fold improvement compared with placebo in progression-free survival, representing a 65% risk reduction for progression. The purpose of this analysis was to investigate the efficacy and safety of everolimus in the Japanese subgroup enrolled in the RADIANT-3 study. Methods Subgroup analysis of the Japanese patients was performed comparing efficacy and safety between everolimus 10 mg/day orally (n = 23) and matching placebo (n = 17). The primary endpoint was progression-free survival. Safety was evaluated on the basis of the incidence of adverse drug reactions. Results Progression-free survival was significantly prolonged with everolimus compared with placebo. The median progression-free survival was 19.45 months (95% confidence interval, 8.31–not available) with everolimus vs 2.83 months (95% confidence interval, 2.46–8.34) with placebo, resulting in an 81% risk reduction in progression (hazard ratio, 0.19; 95% confidence interval, 0.08–0.48; P< 0.001). Adverse drug reactions occurred in all 23 (100%) Japanese patients receiving everolimus and in 13 (77%) patients receiving placebo; most were grade 1/2 in severity. The most common adverse drug reactions in the everolimus group were rash (n = 20; 87%), stomatitis (n = 17; 74%), infections (n = 15; 65%), nail disorders (n = 12; 52%), epistaxis (n = 10; 44%) and pneumonitis (n = 10; 44%). Conclusions These results support the use of everolimus as a valuable treatment option for Japanese patients with advanced pancreatic neuroendocrine tumours. PMID:22859827

Prediction of radiant heat flux from horizontal propane jet fire

International Nuclear Information System (INIS)

Zhou, Kuibin; Liu, Jiaoyan; Jiang, Juncheng

2016-01-01

Highlights: • Line source model for the radiant heat flux from horizontal jet fire is proposed. • A review on the difference between horizontal and vertical jet fires is conducted. • Effects of lift-off distance and flame shape are discussed for the line source model. • Line source model gives encouraging results relative to the validity of model system. - Abstract: Jet fires are often reported to occur in process industry with lots of hazardous heat energy released. A line source model describing the flame emissive power and subsequent heat flux radiated from a horizontal propane jet fire is evaluated through a testing against experimental fire data and comparison against other models. By a review on the jet flame behavior, the correlations of the lift-off distance, flame length and radiative fraction are proposed to close the line source model in theory. It is found that the fuel jet direction holds a considerable effect on the flame behavior by comparison between horizontal and vertical jet fires. Results indicate that the lift-off distance and the flame shape influence the model prediction to some extent. Comparison of model predictions against data collected in the near field and predictions from the point source model and multipoint source model gives encouraging results relative to the validity of model system.