• Title/Summary/Keyword: thermal rating

Search Result 119, Processing Time 0.031 seconds

A Study for Development of Ratio Beale Measuring Pain Using Korean Pain Tersm (통증어휘를 이용한 통증비율척도의 개발연구)

  • 이은옥;윤순녕;송미순
    • Journal of Korean Academy of Nursing
    • /
    • v.14 no.2
    • /
    • pp.93-111
    • /
    • 1984
  • The main purpose of this study is to develop a ratio scale measuring level of pain using Korean pain terms. The specific purposes of this study are to identify the degree of pain of each pain term in each subclass: to classify each subclass in terms of dimensions of pain; and to analyze factors of the Korean pain ratio scale clustering together. One hundred an4 fifty eight pain terms which were originally identified as representative terms and their synonyms were used for data collection. Fifty eight nursing professors ana sixty one medical doctors who have contacted with patients having pain were asked to rate the weight of each pain term on a visual analogue scale. Subclasses in which ranks of pain terms were same f s findings in two previous studies were 1) thermal 3 am 2) cavity pressure, 3) single stimulating pain, 4) radiation pain. and 5) chemical pain. Subclasses in which ranks of pain terms were confused were 1) incisive pressure, and 2) cold pain. Subclasses in which one new pain term was added were 1) inflammatory-repeated pain, 2) punctuate pressure, 3) constrictive pressure, 4) fatigue-related pressure, and 5) suffering-relate4 pain. Subclasses in which two new pain terms were added were 1) traction pressure, 2) peripheral nerve pain, 3) dull pain, 4) pulsation-related pain, 5) digestion-related pain, 6) tract pain, and 7) punishment-related pain. Subclass in which 3 new pain terms were included was fear-related pain. Rating scores of 5 words in 4 subclasses were significantly different between the normal group and the extreme group of subjects in terms of subjective rating. Only one word among 6 words was that newly added to the scale. Rating scores of 12 words in 9 subclasses were significantly different between doctor group and nursing professor group. Among these 12 words, only 3 were those newly added to the scale. In comparison of these 12 words, mean scores of the nursing professors were always 7 to 16 points higher than those of the medical doctors. In the analysis of judgement of subjects in terms of dimensions of pain terms, subclasses of dull pain, cavity pressure, tract pain and cold pain were suggested to be included in the miscellaneous dimension. As a result of factor analysis of the ratings given to 96 pain words using principal components analysis without iteration and with varimax rotation limiting the number of factors to 4, factors of severe pain (factor I) mild-moderate pain (factor II) , causative pain (factor III) and temperature-related pain(factor IV) were extracted with the factor loading above 0.388. When the pain words were re-arranged on the bases of factor loading above 0.368, number of factors decreased to only first two factors. Maximum score of pain word in factor II was 46.17 and the minimum score of the factor I was 45.36. Further studies are needed to identify the validity, reliability, sensitivity and practicability of this ratio scale using patients having various sources of pain.

  • PDF

A comparative analysis of the total window thermal transmittance simulation result according to the evaluation method of effective conductivity(λeff) of frame cavity - Focused on unventilated frame cavity simulation results of single window - (창틀 공기층의 유효 열전도율(λeff) 산정방법 차이가 창 전체 열관류율(Uw) 시뮬레이션 결과에 미치는 영향에 대한 비교 분석 - 단창 창틀의 비환기 공기층에 대한 시뮬레이션을 중심으로 -)

  • Lee, Yong-jun;Oh, Eun-joo;Kim, Sa-kyum;Choi, Gyeong-seok;Kang, Jae-sik
    • KIEAE Journal
    • /
    • v.16 no.2
    • /
    • pp.79-85
    • /
    • 2016
  • Purpose: It is difficult to calculate frame U-value because of the two reason. First is selection of air properties in cavity. Second is calculation method in window frame. For this reason, it is important to decide cavity properties in window frame. However, international standards offered different method(ISO 15099, ISO 10077) and air properties was changed according to the two methods. The aim of this study was to suggest method for deriving accurate frame U-value using international standard methods and CFD simulation. Method: First, this study conducted analysis calculation method of ISO 15099 and ISO 10077. And, CFD simulation conducted based on same condition. Finally, ISO calculation and CFD simulation results were verified through comparison with real experiment results. Result: The results show that effective conductivity of ISO 15099 was the highest value. ISO 10077 and CFD result followed. The convergent values of ISO 10077 was the highest. ISO 15099 and CFD followed. ISO calculation reflecting CFD simulation results will reduce error with experimental results.

Efficacy of Cooling Vest for Auxiliary Body Cooling in Hot Environments (1) -Thermophysiological Response of Human Body in Local Cooling- (고온환경 하에서 착용하는 인체냉각 보조도구로서의 Cooling Vest 연구(1) -Local Cooling에 따른 인체의 온열생리학적 특성-)

  • Kwon, Oh Kyung;Kim, Jin-A;Kim, Tae Kyu
    • Fashion & Textile Research Journal
    • /
    • v.2 no.3
    • /
    • pp.265-271
    • /
    • 2000
  • Heat stress results in fatigue, a decline in strength, alertness., and mental capacity. The problem is compounded when high humidity exists. To help relieve worker heat stress, many types of cooling units are marketed. While workers may experience some cooling, critical body core temperatures often continue to elevate. This study was designed to find the effects of three kinds of cooling vest with portable frozen gel strips on thermophysiological parameters and on temperature and humidity within clothing. The heart rate, rectal, and skin temperature as well as sweat rate and clothing microclimate were measured during 80 min in 5 healthy males. Inquiries were also made into the subjective rating thermal, humidity comfort, and fatigue sensations. The main findings in our experiments are as follows: (a) Physiological parameters such as rectal temperature was the lowest in garb A1, intermediate in garb A, and the highest in garb A2 throughout the experiment. And mean skin temperature was the lowest in garb A, intermediate in garb A1, and the highest in garb A2; (b) Temperature and humidity within clothing (back) were garb in Al, intermediate in garb A, and the highest in garb A2. But the temperature and humidity within clothing (chest) were garb in A, intermediate in garb A1, and the highest in garb A2; (c) Most participants (4 out of 5 persons) answered that they felt more comfortable and fatigueless in garb A1 than in garb A and A2. It is concluded that local cooling in garb A1 of the upper torso could physiological reduce the thermal strain in participants wearing cooling vest.

  • PDF

Thermo-mechanical analysis of reinforced concrete slab using different fire models

  • Suljevic, Samir;Medic, Senad;Hrasnica, Mustafa
    • Coupled systems mechanics
    • /
    • v.9 no.2
    • /
    • pp.163-182
    • /
    • 2020
  • Coupled thermo-mechanical analysis of reinforced concrete slab at elevated temperatures from a fire accounting for nonlinear thermal parameters is carried out. The main focus of the paper is put on a one-way continuous reinforced concrete slab exposed to fire from the single (bottom) side as the most typical working condition under fire loading. Although contemporary techniques alongside the fire protection measures are in constant development, in most cases it is not possible to avoid the material deterioration particularly nearby the exposed surface from a fire. Thereby the structural fire resistance of reinforced concrete slabs is mostly influenced by a relative distance between reinforcement and the exposed surface. A parametric study with variable concrete cover ranging from 15 mm to 35 mm is performed. As the first part of a one-way coupled thermo-mechanical analysis, transient nonlinear heat transfer analysis is performed by applying the net heat flux on the exposed surface. The solution of proposed heat analysis is obtained at certain time steps of interest by α-method using the explicit Euler time-integration scheme. Spatial discretization is done by the finite element method using a 1D 2-noded truss element with the temperature nodal values as unknowns. The obtained results in terms of temperature field inside the element are compared with available numerical and experimental results. A high level of agreement can be observed, implying the proposed model capable of describing the temperature field during a fire. Accompanying thermal analysis, mechanical analysis is performed in two ways. Firstly, using the guidelines given in Eurocode 2 - Part 1-2 resulting in the fire resistance rating for the aforementioned concrete cover values. The second way is a fully numerical coupled analysis carried out in general-purpose finite element software DIANA FEA. Both approaches indicate structural fire behavior similar to those observed in large-scale fire tests.

Prediction of the Occurring Time of Stall for a Booster Fan in a Power Plant Combusting Low Quality Coal through Draft Loss (저품위탄 연소시 탈황용 승압송풍기 실속시점 예측)

  • Kim, Yeong-Gyun;Lee, Jae-Heon
    • Plant Journal
    • /
    • v.8 no.4
    • /
    • pp.34-39
    • /
    • 2012
  • This study presents how low quality coal combustion affects the desulfurizer draft system by correlating of draft loss in a coal-fired thermal power plant and predicts the stall occurrence time of a booster fan. In case of low quality coal, a lot of coal is needed to generate equivalent output power, thereby the rating of increasing draft loss was faster than designed amount of coal. We surely confirmed that draft loss affects the specific energy of a booster fan strongly. On this basis, it is possible to predict the occurring time of stall for a booster fan from current operation specific energy to stall limit specific energy. This study suggests increasing speed of draft loss in each caloric value and the impact of specific energy at a booster fan, it expects to help safe operating in a thermal power plant.

  • PDF

Design of Optimal Thermal Structure for DUT Shell using Fluid Analysis (유동해석을 활용한 DUT Shell의 최적 방열구조 설계)

  • Jeong-Gu Lee;Byung-jin Jin;Yong-Hyeon Kim;Young-Chul Bae
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.18 no.4
    • /
    • pp.641-648
    • /
    • 2023
  • Recently, the rapid growth of artificial intelligence among the 4th industrial revolution has progressed based on the performance improvement of semiconductor, and circuit integration. According to transistors, which help operation of internal electronic devices and equipment that have been progressed to be more complicated and miniaturized, the control of heat generation and improvement of heat dissipation efficiency have emerged as new performance indicators. The DUT(Device Under Test) Shell is equipment which detects malfunction transistor by evaluating the durability of transistor through heat dissipation in a state where the power is cut off at an arbitrary heating point applying the rating current to inspect the transistor. Since the DUT shell can test more transistor at the same time according to the heat dissipation structure inside the equipment, the heat dissipation efficiency has a direct relationship with the malfunction transistor detection efficiency. Thus, in this paper, we propose various method for PCB configuration structure to optimize heat dissipation of DUT shell and we also propose various transformation and thermal analysis of optimal DUT shell using computational fluid dynamics.

An Experimental Study on a Performance Evaluation of Internal Insulation of Buildings Over 20 Years Old (20년 이상 경과된 노후건축물의 단열재 성능평가에 관한 실험적 연구)

  • Kim, Hyun-Jin;Choi, Se-Jin
    • Journal of the Korea Institute of Building Construction
    • /
    • v.19 no.6
    • /
    • pp.539-547
    • /
    • 2019
  • Recently, the international community signed a climate change agreement to prevent global warming. Yet currently, the fossil fuels have been widely used in to supply building energy for cooling and heating. The Green Building certification (G-SEED), an energy efficiency rating for new or existing buildings requires that buildings meet certain conditions. Insulation is used as a building material to reduce the energy supply to buildings and to improve the thermal insulation, and it accounts for more than 90% of the total heat resistance provided by the building surface components that meet the energy-saving design standards of new buildings. In this investigation, a performance evaluation study was conducted through an experimental study by directly extracting the foam polystyrene insulation on-site during the remodeling of a building that was in the range of 22~38 years old. Through tests, it was found that the thermal conductivity of the extrusion method insulation (XPS) was reduced by 48% and the compressive strength of XPS decreased by 36% compared to KS M 3808, which is the initial quality standard. For bead method insulation (EPS) with a thickness of 50mm, the thermal conductivity, the compressive strength, and flexural failure load were similar to the initial quality standard. Therefore, in the calculation of the primary energy requirement per unit area per year, the performance of bead method insulation can be estimated simply by considering the thickness of the insulation, while a correction factor that considers its performance deterioration should be applied when extrusion method insulation is used.

Develolpment of Heat Exchanger for the Humidifier of 3MW MCFC (3MW급 MCFC용 가습기 개발)

  • Kim, Seonhwa;Oh, Yongmin;Kim, Jaesig;Lee, Jeajun
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2010.11a
    • /
    • pp.88.1-88.1
    • /
    • 2010
  • In recent days, the study for the renewable energy is required to supplement traditional energy source. One of the renewable energy of Fuel Cell is classified according to the electrolytes. It is the MCFC (Molten Carbonate Fuel Cell) for this study. One of the equipments of the heat exchangers is important component for efficiency and cost. In MCFC system, several heat exchangers are used according to the application. It is named for the humidifier because it is to preheat the fuel and water so that a reactor will convert some of the incoming fuel to hydrogen. Then, hot side fluid service is used the exhausted gas from the fuel cell and cold side fluid service is the fuel and water. The operation temperature range is about 25~500 Celsius Degree. This heat exchanger has the problems of heat transfer considering to multiphase fluid and phase changing. So it is necessary to analyze the heat transfer characteristics and to propose the reasonable design methodology for the humidifier. In this study, the thermal characteristic for the humidifier is estimated by using commercial tool of heat exchanger design and rating. And this study provides the testing methodology and presents the results for test facility of fabrication and for testing.

  • PDF

Analysis of Energy Performance and Green Strategies in the Foreign High-Performance Buildings

  • Park, Doo-Yong;Kim, Chul-Ho;Lee, Seung-Eon;Yu, Ki-Hyung;Kim, Kang-Soo
    • KIEAE Journal
    • /
    • v.15 no.3
    • /
    • pp.21-28
    • /
    • 2015
  • Purpose: In this study, we analyzed the energy performance levels and high-performance technology trends through the case studies of foreign high-performance buildings. Method: Buildings built within 10 years were selected for the analysis of recent trends. we analyzed the buildings of U.S.A, Germany and Japan using LEED certified buildings, Passive House certified buildings and CASBEE certified buildings database for the case study of foreign high-performance buildings. A total of 20 high-performance buildings including 14 cases in U.S.A, 4 cases in Germany and 4 cases in Japan were selected. Annual energy consumption levels for 20 high-performance buildings were collected with the actual energy consumption data or data from simulation programs officially recognized by DOE. Annual energy consumption were compared with the energy performance standard of the office buildings in the CBECS database, ASHRAE Standard 90.1-2004 and Building Energy Efficiency Rating System in Korea. Result: The order of the green strategies applied in the main categories are Renewable Energy(63%), Indoor Environment Control(51%), Envelope Improvement(44%) and HVAC System & Control(28%). Specified strategies most widely used in the sub-categories are high-performance Insulation (70%), High Efficiency Heating, Cooling Source Equipment(85%), Photovoltaic&Solar Thermal(80%) and Daylighting(80%).

Characteristics of 15 kVA superconducting fault current limiter (15 kVA급 저항형 초전도 한류기의 전류제한특성)

  • Choi, Hyo-Sang;Kim, Hye-Rim;Hwang, Si-Dole;Kim, Sang-Joon;Lim, Hae-Ryong;Kim, In-Seon;Hyun, Ok-Bae
    • 한국초전도학회:학술대회논문집
    • /
    • v.10
    • /
    • pp.272-275
    • /
    • 2000
  • We investigated a resistive superconducting fault current limiter (SFCL) fabricated using YBCO thin films on 2-inch diameter sapphire substrates. Nearly identical SFCL units were prepared and tested. The units were connected in series and parallel to increase the current and voltage ratings. A serial connection of the units showed significantly unbalanced power dissipation between the units. This imbalance was removed by introducing a shunt resistor to the firstly quenched unit. Parallel connection of the units increased the current rating. An SFCL module of 4 units in parallel, each of which has minimum quench current 25 Ap, was produced and successfully tested at a 220 V circuit. From the resistance increase, we estimated that the film temperature increases to 200 K in 5 msec, and 300 K in 120 msec. Successive quenches revealed that this system is stable without degradation in the current limiting capability under such thermal shocks as quenches at 220 V.

  • PDF