bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Approach to Rating of Vehicle Climate Controls in Hybrid and Electric Driven Vehicles for Energy Efficiency
Authors: Brezger Friedrich , Albers Albert 
Published: October 2013

As part of the auxiliary components, climate controls and heating devices do have a relatively high energy consumption maintaining the comfort in the passenger cabin, which is a problem in the development of hybrid and especially electric vehicles. Hence, these vehicles have high potentials in optimizing the climate control. Several concepts of optimizing energy consumption are well known, such as insulation, glasses with better transmission coefficients, pre-conditioning or heat exchanger of outlet air. The efforts, the complexity, the installation space and the weight of these implementations are increasing. The weight of these additional components has an impact on the energy consumption of the vehicle.
In order to evaluate the interdependencies between the direct energy consumption of possible solutions and their additional effects in early stages of product development, this paper introduces one possible approach for rating. Using the example of a heat pump which will be used for heating and cooling the passenger’s cabin, the applicable modeling in Matlab/Simulink will be demonstrated. One part of this implementation is a comparison of the approach based on Frank [Gro10] and another approach based on Nitz and Hucho [Gro10] in aspects of a sensitivity study. Furthermore, the impact of different insulation methods (glass transmission, insulation of the carriage) at extreme and average environmental boundary conditions as well as the changed weight and installation space is investigated. Therefore an environmental model is introduced which takes day time, season as well as GPS data into account. Target of this investigation is defining the minimum necessary power of a heat pump in the passenger cabin of a commercial vehicle with the smallest possible installation space and increase in weight. By modeling and analyzing this example scenario, sustainable values are derived in order to enable a cost-utility analysis of different vehicles in their respective market segments and the chosen solution of climate control.
Development of the Strength Evaluation Method for Body of Mining Dump Truck Under Actual Operations
Authors: Kita Yasuki , Satou Takayuki , Kitaguchi Atsushi , Sasaki Takashi 
Published: October 2013

The prediction method of the experimental stress wave at the welded joints of the body under actual operations was developed, and the strength evaluation flow based on the method was proposed.
We conducted running tests using a dump truck prototype, the EH3500ACII, as an experimental approach. The high accelerations in longitudinal, vertical, and lateral directions were measured for a sudden stop, bump override and sharp turn test, respectively. The tendencies of the stress waveforms at the welded joints in each running test are in good agreement with those of the acceleration waveforms.
The distinct element (DE) and finite element (FE) methods were used to predict the experimental stress waves. First, the pressure loads of soil were analyzed using DE method. Kanto loam (Japanese soil) was modeled using a large number of particles, and filled a container modeled using rigid plates to form a shape similar to that of actual loads. The soil pressure distributions were formulated with a variety of acceleration loads. Next, the obtained load pressures were applied to the FE model as the load conditions. The stresses at the evaluation points were calculated under a 1G acceleration in the vertical, lateral, and longitudinal directions, respectively. Finally, those stress results and the measured time series acceleration data were multiplied, and the stress waveforms under running conditions were predicted by using a linear superposition method.
When the analytical stresses were compared with the experimental results, the tendencies of the analytical stress variations corresponded well with those of the experimental stress waveforms. On the other hand, the analytical stresses were smaller than the actual experimental values. This was because the weld geometries were not modeled in FE model, and the stress concentrations on the weld toes were not precisely estimated.
The strength evaluation flow was developed by using the soil pressure distribution formulated using the DE analysis, the database of the time series acceleration data obtained from the running tests, the ratio of the stress ranges of the experiment and that of the analysis, Kstress_ratio, and the strength criteria for welded joints. It is possible to evaluate the durability of a new structure model in a short period of time by using this evaluation flow.
Modeling Strategies to Compute Natural Circulation Using CFD in a VHTR After a LOFA
Authors: Tung Yu-Hsin , Johnson Richard W. , Chieng Ching-Chang , Ferng Yuh-Ming 
Published: October 2013

A prismatic gas-cooled very high temperature reactor (VHTR) is being developed under the next generation nuclear plant program (NGNP) of the U.S. Department of Energy, Office of Nuclear Energy. In the design of the prismatic VHTR, hexagonal shaped graphite blocks are drilled to allow insertion of fuel pins, made of compacted tristructural-isotropic (TRISO) fuel particles, and coolant channels for the helium coolant. One of the concerns for the reactor design is the effects of a loss of flow accident (LOFA) where the coolant circulators are lost for some reason, causing a loss of forced coolant flow through the core. In such an event, it is desired to know what happens to the (reduced) heat still being generated in the core and if it represents a problem for the fuel compacts, the graphite core or the reactor vessel (RV) walls. One of the mechanisms for the transport of heat out of the core is by the natural circulation of the coolant, which is still present. It is desired to know how much heat may be transported by natural circulation through the core and upwards to the top of the upper plenum.
It is beyond current capability for a computational fluid dynamics (CFD) analysis to perform a calculation on the whole RV with a sufficiently refined mesh to examine the full potential of natural circulation in the vessel. The present paper reports the investigation of several strategies to model the flow and heat transfer in the RV. It is found that it is necessary to employ representative geometries of the core to estimate the heat transfer. However, by taking advantage of global and local symmetries, a detailed estimate of the strength of the resulting natural circulation and the level of heat transfer to the top of the upper plenum is obtained.
A System Modeling Approach for Active Solar Heating and Cooling System With Phase Change Material (PCM) for Small Buildings
Authors: Ratnanandan Rajeevan , González Jorge E. 
Published: October 2013

The paper presents a study of the performance of an active solar thermal heating and cooling system for small buildings. The work is motivated by the need for finding sustainable alternatives for building applications that are climate adaptable. The energy demand for heating and cooling needs in residential and light commercial buildings in mid-latitudes represent more than 50% of the energy consumed annually by these buildings. Solar thermal energy represents an untapped opportunity to address this challenge with sustainable solutions. Direct heating could be a source for space heating and hot water, and for heat operated cooling systems to provide space cooling. However, a key limitation in mainstreaming solar thermal for heating and cooling has been the size of thermal storage to implement related technologies. We address this issue by coupling a Phase Change Material (PCM) with an adsorption chiller and a radiant flooring system for year round solar thermal energy utilization in Northern climates. The adsorption chiller allows for chill water production driven by low temperature solar thermal energy for summer cooling, and low temperature radiant heating provides for space heating in winter conditions, while hot water demand is supplied year round. These active systems are operated by high performance solar thermal collectors. The PCM has been selected to match temperatures requirements of the adsorption chiller, and the tank was designed to provide three levels of temperatures for all applications; cooling, heating, and hot water. The material selection is paraffin sandwiched with a graphite matrix to increase the conductivity.
The specific objective of the preset work is to provide a system optimization of this active system. The system is represented by a series of mathematical models for each component; PCM tank with heat exchangers, the adsorption machine, the radiant floor, and the solar thermal collectors (Evacuated tubular collectors). The PCM modeling allows for sensible heating, phase change process, and superheating. Parametric simulations are conducted for a defined small building in different locations in US with the objective of defining design parameters for; optimal solar collector array, sizing of the PCM tank, and performance of the adsorption machine and radiant heating system. The monthly and annual solar fractions of the system are also reported.
Large Eddy Simulation of the Flow Over a Flat Plate at Small Incidence Angle With an Advective Sub-Grid Model
Authors: Sampaio L. E. B. , Rezende A. L. T. , Nieckele A. O. 
Published: October 2013

Understanding the flow around thin flat plate at shallow incidence can help in the design of airfoils and sails, as well as flexible wing-based micro air vehicles. Although the geometry is simple, the flow is very complex.
In the present work, the flow field is determined with a LES advective subgrid-scale model (f-LES) which directly adds a force to the original equation, instead of a divergent of a subgrid tensor. This force is built to have an advective nature and to damp only the very smallest modes supported by the spatial discretization. The f-LES model was implemented in the open source code OpenFOAM®. The model prediction was evaluated by examining the decaying of homogeneous isotropic turbulence, and comparing with the traditional Smagorinsky and Dynamic Smagorinsky models.
The flow over a plate with Reynolds number equal to 2.13 × 105 and angle of attack of 1° was analyzed. Average velocity and pressure, as well as, second order statistics were compared with available experimental data, presenting reasonable agreement. Coherent structures are visualized, as well as the evolution vortex tubes.
Correcting radiation survey data to account for increased leakage during intensity modulated radiotherapy treatments
Authors: Kairn T. , Crowe S. B. , Trapp J. V. 
Published: October 2013

Purpose:Intensity modulated radiotherapy (IMRT) treatments require more beam‐on time and produce more linac head leakage to deliver similar doses to conventional, unmodulated, radiotherapy treatments. It is necessary to take this increased leakage into account when evaluating the results of radiation surveys around bunkers that are, or will be, used for IMRT. The recommended procedure of applying a monitor‐unit based workload correction factor to secondary barrier survey measurements, to account for this increased leakage when evaluating radiation survey measurements around IMRT bunkers, can lead to potentially costly overestimation of the required barrier thickness. This study aims to provide initial guidance on the validity of reducing the value of the correction factor when applied to different radiation barriers (primary barriers, doors, maze walls, and other walls) by evaluating three different bunker designs.Methods:Radiation survey measurements of primary, scattered, and leakage radiation were obtained at each of five survey points around each of three different radiotherapy bunkers and the contribution of leakage to the total measured radiation dose at each point was evaluated. Measurements at each survey point were made with the linac gantry set to 12 equidistant positions from 0° to 330°, to assess the effects of radiation beam direction on the results.Results:For all three bunker designs, less than 0.5% of dose measured at and alongside the primary barriers, less than 25% of the dose measured outside the bunker doors and up to 100% of the dose measured outside other secondary barriers was found to be caused by linac head leakage.Conclusions:Results of this study suggest that IMRT workload corrections are unnecessary, for survey measurements made at and alongside primary barriers. Use of reduced IMRT workload correction factors is recommended when evaluating survey measurements around a bunker door, provided that a subset of the measurements used in this study are repeated for the bunker in question. Reduction of the correction factor for other secondary barrier survey measurements is not recommended unless the contribution from leakage is separately evaluated.
Efficacy of Adefovir-Based Combination Therapy for Patients with Lamivudine- and Entecavir-Resistant Chronic Hepatitis B Virus Infection
Authors: Lee Yun Bin , Lee Jeong-Hoon , Choi Won-mook , Cho Young Youn , Yoo Jeong-ju , Lee Minjong , Lee Dong Hyeon , Cho Yuri , Yu Su Jong , Kim Yoon Jun , Yoon Jung-Hwan , Kim Chung Yong , Lee Hyo-Suk 
Published: October 2013

ABSTRACTTreatment strategies for entecavir (ETV)-resistant chronic hepatitis B (CHB) patients are not yet well established. The aim of this study was to evaluate overall antiviral efficacy and to compare the efficacy of combination therapy with adefovir (ADV) plus nucleoside analogues (lamivudine [LAM], telbivudine [LdT], or ETV) in patients infected with LAM- and ETV-resistant hepatitis B virus (HBV) variants. Virologic, biochemical, and serologic responses during combination therapy with ADV plus nucleoside analogues were assessed. Propensity score analysis was used to select a matched group of patients for the comparison of rescue therapy regimens. A total of 67 consecutive patients were analyzed. Complete virologic suppression was achieved in 27 patients. The overall cumulative incidence of complete virologic suppression at month 24 was 47.4%: 44.3% in the LAM or LdT plus ADV group and 51.4% in the group given ETV and ADV. There was no significant difference between these two groups (P= 0.234). The cumulative incidences of complete virologic suppression were still comparable between the two groups selected and matched using the propensity score model (P= 0.419). Virologic breakthrough was observed in 9 patients, and rtA181V substitution was newly detected in one patient. Hepatitis B e antigen (HBeAg) negativity and lower baseline HBV DNA level were associated with complete virologic suppression in univariate analysis. In multivariate analysis, lower baseline HBV DNA level remained an independent predictor. In conclusion, combination therapy with ADV plus nucleoside analogues fails to show sufficient antiviral efficacy in CHB patients with resistance to both LAM and ETV. Further study is warranted to evaluate the efficacy of a more potent tenofovir-based regimen in such patients.
The effectiveness of exercise interventions to prevent sports injuries: a systematic review and meta-analysis of randomised controlled trials
Authors: Lauersen Jeppe Bo , Bertelsen Ditte Marie , Andersen Lars Bo 
Published: October 2013

BackgroundPhysical activity is important in both prevention and treatment of many common diseases, but sports injuries can pose serious problems.ObjectiveTo determine whether physical activity exercises can reduce sports injuries and perform stratified analyses of strength training, stretching, proprioception and combinations of these, and provide separate acute and overuse injury estimates.Material and methodsPubMed, EMBASE, Web of Science and SPORTDiscus were searched and yielded 3462 results. Two independent authors selected relevant randomised, controlled trials and quality assessments were conducted by all authors of this paper using the Cochrane collaboration domain-based quality assessment tool. Twelve studies that neglected to account for clustering effects were adjusted. Quantitative analyses were performed in STATA V.12 and sensitivity analysed by intention-to-treat. Heterogeneity (I2) and publication bias (Harbord's small-study effects) were formally tested.Results25 trials, including 26 610 participants with 3464 injuries, were analysed. The overall effect estimate on injury prevention was heterogeneous. Stratified exposure analyses proved no beneficial effect for stretching (RR 0.963 (0.846–1.095)), whereas studies with multiple exposures (RR 0.655 (0.520–0.826)), proprioception training (RR 0.550 (0.347–0.869)), and strength training (RR 0.315 (0.207–0.480)) showed a tendency towards increasing effect. Both acute injuries (RR 0.647 (0.502–0.836)) and overuse injuries (RR 0.527 (0.373–0.746)) could be reduced by physical activity programmes. Intention-to-treat sensitivity analyses consistently revealed even more robust effect estimates.ConclusionsDespite a few outlying studies, consistently favourable estimates were obtained for all injury prevention measures except for stretching. Strength training reduced sports injuries to less than 1/3 and overuse injuries could be almost halved.
Age-related variation in sexual behaviours among heterosexual men residing in Brazil, Mexico and the USA
Authors: August Euna M , Daley Ellen , Kromrey Jeffrey , Baldwin Julie , Romero-Daza Nancy , Salmeron Jorge , Lazcano-Ponce Eduardo , Villa Luisa L , Bryant Carol A , Giuliano Anna R 
Published: October 2013

ObjectiveTo compare the prevalence of demographic characteristics and sexual behaviours across age groups and to estimate their significance in predicting sexual risk factors by age cohort.MethodsThis cohort study examined sexually transmitted infection (STI) prevalence among heterosexual men in Brazil, Mexico and the USA (N=3047). Participants completed a sexual risk factor questionnaire and were tested for chlamydia, gonorrhoea, syphilis and genital herpes. We examined sexual risk in the study population through a composite measure of STI positivity by age cohort (young: 18–30 years; middle-aged: 31–44 years; older: 45–70 years). Multivariable logistic regression models were used to generate adjusted odds ratios (AORs) and 95% confidence intervals (CIs).ResultsWe found that STI positivity varied significantly by age group among heterosexual men by a number of covariates. In younger men, having more advanced education had a protective effect (16 years: AOR=0.37, 95% CI 0.15– 0.92), whereas higher numbers of sexual partners elevated the risk for STIs (20–49 partners: AOR=2.06, 95% CI 1.04–4.06; ≥50 partners: AOR=4.33, 95% CI 1.74–10.76). Middle-aged men who were black (AOR=1.64, 95% CI 1.10–2.42) and divorced/separated/widowed (AOR=1.91, 95% CI 1.21–3.02) had an increased risk for a positive STI test. Among older men, a younger age at first vaginal sexual encounter (AOR=3.75, 95% CI 1.45–9.74) and a history of exchanging sex for money or drugs heightened STI risk (AOR=2.30, 95% CI 1.0–5.04).ConclusionsThese findings demonstrate that age-related life experiences among heterosexual men influence sexual risk and STI transmission. This topic warrants further investigation to support the development and implementation of targeted interventions that may potentially reduce adverse sexual health outcomes.
Prospects for coitally-dependent hormonal contraception: perspectives from women in urban Kenya and Nigeria
Authors: Chin-Quee Dawn , L'Engle Kelly , Otterness Conrad 
Published: October 2013

IntroductionEmergency contraceptive pills (ECPs) were developed and marketed with the emergency aspect firmly in mind, but research and anecdotal evidence indicate that some women use them as a form of regular contraception, spurring efforts in the reproductive health community to explore the development of a coitally-dependent oral contraceptive pill.MethodsWe asked women of reproductive age in Nairobi, Kenya and Lagos, Nigeria how likely they would be to use a hypothetical pericoital pill and why.ResultsBivariate logistic regressions indicated that women aged 18–35 years, with secondary education or higher, and who had ever used condoms or short-acting methods, were more likely to say that they would use this hypothetical pill. Women who had ever used a family planning method or ECPs were also more likely to say they would use this pill. The likely adopters reported that they would use the pericoital method if it prevented pregnancy with little or no health problems and was convenient and easy to use.ConclusionThe findings suggest that should a safe and effective pericoital hormonal pill become available then a significant number of women would adopt this method.
Dealing with uncertainty
Authors: Wolf Hannes , Herrmann Klaus , Rothermel Kurt 
Published: October 2013

Processes in the healthcare domain are characterized by coarsely predefined recurring procedures that are flexibly adapted by the personnel to suite-specific situations. In this setting, a workflow management system that gives guidance and documents the personnel's actions can lead to a higher quality of care, fewer mistakes, and higher efficiency. However, most existing workflow management systems enforce rigid inflexible workflows and rely on direct manual input. Both are inadequate for healthcare processes. In particular, direct manual input is not possible in most cases since (1) it would distract the personnel even in critical situations and (2) it would violate fundamental hygiene principles by requiring disinfected doctors and nurses to touch input devices. The solution could be activity recognition systems that use sensor data (e.g., audio and acceleration data) to infer the current activities by the personnel and provide input to a workflow (e.g., informing it that a certain activity is finished now). However, state-of-the-art activity recognition technologies have difficulties in providing reliable information.
We describe a comprehensive framework tailored for flexible human-centric healthcare processes that improves the reliability of activity recognition data. We present a set of mechanisms that exploit the application knowledge encoded in workflows in order to reduce the uncertainty of this data, thus enabling unobtrusive robust healthcare workflows. We evaluate our work based on a real-world case study and show that the robustness of unobtrusive healthcare workflows can be increased to an absolute value of up to 91% (compared to only 12% with a classical workflow system). This is a major breakthrough that paves the way towards future IT-enabled healthcare systems.