• Title/Summary/Keyword: comparative assessment

Search Result 942, Processing Time 0.031 seconds

Comparative Efficiency Evaluation of Air Cleaners for Improving Indoor Air Quality (실내용 공기청정기 유형별 실내환경개선 성능에 대한 비교평가)

  • Na, Kyung-Ho;Son, Jin-Seok;Sung, Kijune;Jang, Young-Kee
    • Journal of Environmental Impact Assessment
    • /
    • v.14 no.3
    • /
    • pp.109-115
    • /
    • 2005
  • This study was conducted to evaluate the efficiency of indoor air cleaners and to inform how to select them correctly to the users. The efficiencies of removing suspended bacteria per hour were $64.3{\pm}13.1%$ for filter, wet, and complex type, respectively, which showed the complex type was the most efficient. The removal efficiencies of formaldehyde (HCHO) after two hours operation of air cleaners showed 88.3% and 81.1% for filter and wet type, respectively. The efficiency of complex type, with removal rate of 55.5~58.4%, was decreased after 30 minutes operation. Therefore, it is recommended to perform over 60 minutes when doing air cleaner certification test for HCHO removal efficiency. Generally, air cleaners having low wind volume showed higher efficiency. All tested air cleaners had no potential for removing of volatile organic compounds (VOCs), which is toxic substances, and it is desirable to develop a device which can control these substances. The results also confirmed that there was no ozone production from all tested air cleaners. And it is recommended to ventilate for 20 minutes every four hours to maintain 50% ventilation status.

Comparative Evaluation of Interpolation Accuracy for $CO_2$ Emission using GIS (GIS를 활용한 이산화탄소 농도 보간 정확도 비교평가)

  • Kim, Jun-Hyun;Choi, Jin-Ho;Kim, Chung-Sil
    • Journal of Environmental Impact Assessment
    • /
    • v.19 no.6
    • /
    • pp.647-656
    • /
    • 2010
  • As the $CO_2$ from buildings take up approximately 25% of the total $CO_2$ emission, the need for regulating and managing this emission is urgently required. Thus this study recognizes $CO_2$ emission status for diverse purposes and suggests accurate interpolation method for visualizing $CO_2$ emission as the basic data for regulating and managing $CO_2$ emission by applying IDW, Spline, and Kringing method. Results showed that Gaussian Function application among the Kriging methods had the highest accuracy in its estimations, with 3.049 with RMSE standards. This could be used as the basic data when visualizing $CO_2$ emission status, which is a necessity for many local and federal governments that are to regulate and manage $CO_2$ emission. This study shows that the interpolation is very appropriative method in recognizing $CO_2$ emission characteristics for regional climate change measures.

Comparative Study of Text Entry Speed and Accuracy Using the Three Different Keyboard Type in Students with Cerebral Palsy: Case Study (키보드 유형에 따른 뇌성마비 학생의 문자입력 속도 및 정확도 비교: 사례연구)

  • Jeong, Dong-Hoon
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.10 no.1
    • /
    • pp.23-35
    • /
    • 2015
  • PURPOSE: People with physical disabilities such as cerebral palsy usually experience obstacles when interacting with computer through conventional keyboard because of their motor disabilities. The purpose of this study is empirically compare of text entry(alphabet and word) speed and accuracy using the three different keyboard type on four students(male 2 and female 2) with cerebral palsy. METHODS: This research design used a replicated single-case experimental approach to compare the individual performance. An alternating treatments design was used to examine the effectiveness of standard QWERTY keyboard and alternative keyboard(mini and big keyboard) on computer access for students with cerebral palsy. To avoid changes in posture that influence a keyboard character entry training and evaluation was carried out using his sitting in a wheelchair. Compass software program used in this study as an assessment tool to measure speed and accuracy when performance of text entry(alphabet and word). This was repeated until the stable status of reaction time. RESULTS: As a result, the alternative keyboard seems to be the most effective device for students with cerebral palsy to perform text entry. But various factors such as peculiarity of motor disabilities, experience and preferences of the user are heavily related. CONCLUSION: Thus, we must perform the objective and systematic assessment for computer access and if sustained training is accomplished, it could to improve speed and accuracy of text entry(alphabet and word).

Comparative Evaluation of Indoor Temperature in Spring according to Sitting Orientation of Tower-Type Apartments (탑상형 아파트의 배치방향별 봄철 실내온도 비교평가)

  • Kim, Jun Hyun;Um, Jung-Sup
    • Journal of Environmental Impact Assessment
    • /
    • v.20 no.2
    • /
    • pp.175-185
    • /
    • 2011
  • It is usual for energy consumption in accordance with facing and sitting direction of tower-type apartments to be calculated by the official statistics or computer simulation. Previous studies for energy consumption appear to be very limited due to the dependence on flat type of apartment. Acknowledging these constraints, an empirical study for a tower type apartment was conducted to demonstrate how a on-site indoor temperature measurement in spring can be used to assist in estimating the total energy consumption in terms of facing and sitting orientation specific settings. The results indicate that maximum temperature difference in spring was identified as $1.16^{\circ}C$ between south and eastern direction. It is known that raising $1^{\circ}C$ indoor temperature require 7% more energy consumption than normal. The $1.16^{\circ}C$ difference means that sitting direction of tower type apartment is a crucial explanatory variable as unit of analysis for energy consumption. It was demonstrated that the indoor temperature could be used effectively as an indicator to estimate energy consumption among various sitting direction of tower type apartments. It is anticipated that this research output could be used as a valuable reference to support more scientific and objective decision-making for facing and sitting orientation of tower type apartments.

Blood glucose levels, insulin concentrations, and insulin resistance in healthy women and women with premenstrual syndrome: a comparative study

  • Zarei, Safar;Mosalanejad, Leili;Ghobadifar, Mohamed Amin
    • Clinical and Experimental Reproductive Medicine
    • /
    • v.40 no.2
    • /
    • pp.76-82
    • /
    • 2013
  • Objective: To compare the blood glucose levels, insulin concentrations, and insulin resistance during the two phases of the menstrual cycle between healthy women and patients with premenstrual syndrome (PMS). Methods: From January of 2011 to the August of 2012, a descriptive cross-sectional study was performed among students in the School of Medicine of Jahrom University of Medical Sciences. We included 30 students with the most severe symptoms of PMS and 30 age frequency-matched healthy controls. We analyzed the serum concentrations of glucose, insulin, and insulin resistance by using the glucose oxidase method, radioimmunometric assay, and homeostasis model assessment of insulin resistance equation, respectively. Results: No significant differences between the demographic data of the control and PMS groups were observed. The mean concentrations of glucose of the two study groups were significantly different during the follicular and luteal phases (p=0.011 vs. p<0.0001, respectively). The amounts of homeostasis model assessment of insulin resistance of the two study groups were significantly different in the luteal phase (p=0.0005). Conclusion: The level of blood glucose and insulin resistance was lower during the two phases of the menstrual cycle of the PMS group than that of the controls.

PROBABILISTIC SEISMIC ASSESSMENT OF BASE-ISOLATED NPPS SUBJECTED TO STRONG GROUND MOTIONS OF TOHOKU EARTHQUAKE

  • Ali, Ahmer;Hayah, Nadin Abu;Kim, Dookie;Cho, Ung Gook
    • Nuclear Engineering and Technology
    • /
    • v.46 no.5
    • /
    • pp.699-706
    • /
    • 2014
  • The probabilistic seismic performance of a standard Korean nuclear power plant (NPP) with an idealized isolation is investigated in the present work. A probabilistic seismic hazard analysis (PSHA) of the Wolsong site on the Korean peninsula is performed by considering peak ground acceleration (PGA) as an earthquake intensity measure. A procedure is reported on the categorization and selection of two sets of ground motions of the Tohoku earthquake, i.e. long-period and common as Set A and Set B respectively, for the nonlinear time history response analysis of the base-isolated NPP. Limit state values as multiples of the displacement responses of the NPP base isolation are considered for the fragility estimation. The seismic risk of the NPP is further assessed by incorporation of the rate of frequency exceedance and conditional failure probability curves. Furthermore, this framework attempts to show the unacceptable performance of the isolated NPP in terms of the probabilistic distribution and annual probability of limit states. The comparative results for long and common ground motions are discussed to contribute to the future safety of nuclear facilities against drastic events like Tohoku.

Comparative Analysis of SOx Emission-Compliant Options for Marine Vessels from Environmental Perspective

  • Jeong, Byongug
    • Journal of Power System Engineering
    • /
    • v.22 no.1
    • /
    • pp.72-78
    • /
    • 2018
  • With growing concerns over air pollutions attributed to shipping activities, the international maritime organization has enacted a series of stringent regulations. In particular, MARPOL Annex IV Reg. 16 requires sulfur contents from exhaust gases of marine engines to be progressively reduced. To comply with this regulation, three feasible options have been introduced: using LNG as a marine fuel, using heavy fuel oil with the scrubber system, and using the marine gas oil (a type of low sulfur fuel oil). For the objectives of this paper, the holistic environmental impacts pertinent to these options were investigated and compared in ways that the flows of energy and emission were tracked and quantified through the life cycle of the ship. Research findings obtained from a case study with a large bulk carrier showed that the use of the scrubber system to purify heavy fuel oil would produce relatively fewer amounts of emissions attributing to global warming than other two options. On the other than, the use of LNG would be the way to operate the ship in a cleaner way in terms of reducing the acidification, eutrophication, and photochemical effects. Throughout the analysis, the excellence of life cycle assessment was proven to shift the environmental impact of marine systems from the short-term view to the long-term one.

Comparative Crashworthiness Assessment of the ULSAB-AVC Model with Advance High Strength Steel and with Low Strength Steel (고강도 강판 ULSAB-AVC 모델과 일반강판 모델의 충돌성능 비교 평가)

  • Yoon, Jong-Heon;Huh, Hoon;Kim, Se-Ho;Kim, Hong-Kee;Park, Seung-Ho
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.14 no.3
    • /
    • pp.22-27
    • /
    • 2006
  • As the regulation and assessment program for safety of passengers become stringent, automakers are required to develop lighter and safer vehicles. In order to fulfill both requirements which conflict with each other, automobile and steel companies have proposed the application of AHSS(Advance High Strength Steel) such as DP, TRIP and martensite steel. ULSAB-AVC model is one of the most remarkable reactions to offer solutions with the use of steel for the challenge to improve simultaneously the fuel efficiency, passenger safety, vehicle performance and affordability. This paper is concerned with the crash analysis of ULSAB-AVC model according to the US-SINCAP in order to compare the effectiveness between the model with AHSS and that with conventional steels. The crashworthiness is investigated by comparing the deformed shape of the cabin room, the energy absorption characteristics and the intrusion velocity of a car.

Seismic Performance Assessment of a Mid-Rise RC Building subjected to 2016 Gyeongju Earthquake (2016년 경주지진에 의한 중층 RC 건물의 내진 성능 평가)

  • Lee, Do Hyung;Jeon, Jong-Su
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.20 no.7_spc
    • /
    • pp.473-483
    • /
    • 2016
  • In this paper, seismic performance assessment has been examined for a mid-rise RC building subjected to 2016 Gyeongju earthquake occurred in Korea. For the purpose of the paper, 2D external and internal frames in each direction of the building have been employed in the present comparative analyses. Nonlinear static pushover analyses have been conducted to estimate frame capacities. Nonlinear dynamic time-history analyses have also been carried out to examine demands for the frames subjected to ground motions recorded at stations in near of Gyeongju and a previous earthquake ground motion. Analytical predictions demonstrate that maximum demands are significantly affected by characteristics of both spectral acceleration response and spectrum intensity over a wide range of periods. Further damage potential of the frames has been evaluated in terms of fragility analyses using the same ground motions. Fragility results reveal that the ground motion characteristics of the Gyeongju earthquake have little influence on the seismic demand and fragility of frames.

A Comparative Study on the Care Services According to Care Levels in the Korean and German Home Care System (한국과 독일 방문요양의 등급별 급여 비교 연구)

  • Park, Jong Duk
    • Journal of Home Health Care Nursing
    • /
    • v.23 no.2
    • /
    • pp.243-252
    • /
    • 2016
  • Purpose: This study aims to classify multiple forms of home care services from a service user's perspective. By comparing the German system to the Korean one, this study seeks to find better ways of enhancing client-centered care. Methods: The data of 121 home care users were collected from six home care centers that had under the management of nursing managers for more than five years. The researcher used a German instrument to estimate the level of care. Results: High correlation was found between German and Korean assessment criteria (r=0.81, p<.001). However, compared to their German counterparts, Korean home care providers allocated more time towards provision of domestic help per daily visit. German home care providers allocated more time towards services relating to provision of support for physical activities, including personal hygiene. It was confirmed that the level of care in Korea does not correlate with either the categories of home care services and duration. Conclusion: Therefore, care services should be offered according to long-term care needs. This study suggests a need for systematic care aimed at strengthening the client's autonomy which should be properly planned, implemented, and managed.