• Title/Summary/Keyword: equivalence test

Search Result 168, Processing Time 0.029 seconds

The Effects of a Low Intensity Excercise Program on Psychosocial Factors of Excercise and Physical Factors in Elderly Women (저강도 운동프로그램이 여성노인의 운동에 대한 사회.심리적 및 신체적 요인에 미치는 효과)

  • Nam, Mi-Ra;Kim, Young-Hee;Ahn, Ok-Hee;Yang, Bok-Sun
    • Research in Community and Public Health Nursing
    • /
    • v.18 no.3
    • /
    • pp.373-381
    • /
    • 2007
  • Purpose: An exercise program, which was composed of motions simple and easy to follow, was developed and applied to aged women as a way to improve their health conditions. Method: To ascertain the effects of the exercise, which was conducted twice a week and 16 times in total for 8 weeks from September 10 to November 5, 2005 in two experimental groups (31 Persons) and a control group (31 persons), this study conducted quasi-experiments of nonequivalent control group pre-post test design. Data were analyzed using SPSS/PC Win 10.0, the reliability of the measuring tools using Cronbach's alpha, the verification of equivalence for general properties and dependent variables using Chi-square test and t-test, and the verification of hypotheses using t-test and ANCOVA. Results: After the exercise program. the aged women showed profitable evaluation of decisional balance, high feeling of self-efficacy as well as improved subjective awareness of health. Their diastolic blood pressure and total cholesterol were also reduced significantly after the exercise. Conclusion: After the conduct of the exercise program for 8 weeks, aged women showed increased profitable decisional balance, self-efficacy and subjective awareness of health. This suggests that continuous and proper exercise is effective as an intervention for health improvement for the aged as well as the prevention of and recovery from geriatric diseases.

  • PDF

Characteristics of Flue Gas Using Direct Combustion of VOC and Ammonia (휘발성 유기 화합물 및 암모니아 직접 연소를 통한 배기가스 특성)

  • Kim, JongSu;Choi, SeukCheun;Jeong, SooHwa;Mock, ChinSung;Kim, DooBoem
    • Clean Technology
    • /
    • v.28 no.2
    • /
    • pp.131-137
    • /
    • 2022
  • The semiconductor process currently emits various by-products and unused gases. Emissions containing pollutants are generally classified into categories such as organic, acid, alkali, thermal, and cabinet exhaust. They are discharged after treatment in an atmospheric prevention facility suitable for each exhaust type. The main components of organic exhaust are volatile organic compounds (VOC), which is a generic term for oxygen-containing hydrocarbons, sulfur-containing hydrocarbons, and volatile hydrocarbons, while the main components of alkali exhaust include ammonia and tetramethylammonium hydroxide. The purpose of this study was to determine the combustion characteristics and analyze the NOX reduction rate by maintaining a direct combustion and temperature to process organic and alkaline exhaust gases simultaneously. Acetone, isopropyl alcohol (IPA), and propylene glycol methyl ether acetate (PGMEA) were used as VOCs and ammonia was used as an alkali exhaust material. Independent and VOC-ammonia mixture combustion tests were conducted for each material. The combustion tests for the VOCs confirmed that complete combustion occurred at an equivalence ratio of 1.4. In the ammonia combustion test, the NOX concentration decreased at a lower equivalence ratio. In the co-combustion of VOC and ammonia, NO was dominant in the NOX emission while NO2 was detected at approximately 10 ppm. Overall, the concentration of nitrogen oxide decreased due to the activation of the oxidation reaction as the reaction temperature increased. On the other hand, the concentration of carbon dioxide increased. Flameless combustion with an electric heat source achieved successful combustion of VOC and ammonia. This technology is expected to have advantages in cost and compactness compared to existing organic and alkaline treatment systems applied separately.

Reliability and Validity Study on the Korean Version of the Fullerton Advanced Balance Scale (한국어판 플러턴 어드밴스드 균형 척도의 신뢰도와 타당도 연구)

  • Kim, Gyoung-mo
    • Physical Therapy Korea
    • /
    • v.23 no.1
    • /
    • pp.31-37
    • /
    • 2016
  • Background: The assessment tool developed in other countries should be translated into Korean language using rigorous methodological approaches in order to be used in Korea. Because these procedures are insufficient for establishing the cross-cultural and linguistic equivalence, the need for statistical methods is raised. The Fullerton Advanced Balance Scale was translated into Korean and the content validity was verified through the back translation method, but the reliability and validity have not yet been proven by statistical methods. Objects: The purpose of this study was to investigate the reliability and validity of the Korean version of the Fullerton Advanced Balance Scale (KFAB) by statistical methods in elderly people. Methods: A total of 97 elderly adults (39 males and 58 females) participated in this study. Internal consistency of the KFAB was measured using Cronbach's alpha and an intraclass correlation coefficient (ICC) was used to assess test-retest reliability between the two measurement sessions. Concurrent validity was measured by comparing the KFAB responses with the Korean version of the Berg Balance Scale (KBBS) using the Spearman correlation coefficient. Construct validity of the KFAB was measured using the exploratory factor analysis to evaluate the unidimensionality of the questionnaire. The significance level was set at ${\alpha}=.05$. Results: The internal consistency of the KFAB was found be adequate with Cronbach's alpha (.96), and test-retest reliability was excellent as evidenced by the high ICC (r=.996). Concurrent validity showed high correlation between the KFAB and KBBS (r=.89, p<.001). Construct validity was evaluated using exploratory factor analysis. The result from Bartlett test of sphericity was statistically significant (p<.001), and the value of Kaiser-Meyer-Olkin measure of sampling adequacy was .93. Exploratory factor analysis revealed the existence of only one dominant factor that explained 76.43% of the variance. Conclusion: The KFAB is a reliable, valid and appropriate tool for measuring the balance functions in elderly people.

Performance Test of Metal 3D Printed Micro Gas Turbine Engine Combustor (초소형 가스터빈 엔진용 금속 3D 프린팅 연소기 성능 시험)

  • Kim, Jaiho;Kim, Hyungmo;Park, Poomin;Rhee, Dongho
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.23 no.6
    • /
    • pp.51-58
    • /
    • 2019
  • In this study, a set of performance tests on 3D-printed combustor components were carried out to investigate the performance of 3D-printed component and its feasibility for micro gas turbine engines. The test were conducted for four different equivalence ratios under two different engine operating conditions. The measurement results show that the tested combustor had a low total pressure loss coefficient and a uniform exit temperature distribution. However, the combustion efficiency values are less than 93.5% owing to the large amount of UHC and CO, which is considerably lower than a typical gas turbine engine combustor. The performance data obtained from the tests will be used for combustor performance improvements using 3D-printing technology.

The Effect of Inter Dental Brush Education on the Dental Plaque Index and the Degree of Halitosis for Elementary School Students (치간 칫솔 교육이 초등학생의 치면 세균막 지수와 구취 정도에 미치는 효과)

  • Lee, Ha Na;Kim, Joo Hyun
    • Journal of Korean Biological Nursing Science
    • /
    • v.16 no.1
    • /
    • pp.8-16
    • /
    • 2014
  • Purpose: This study determined the effect of inter dental brush education on the dental plaque index, and the degree of halitosis for elementary school students. Methods: The study was performed on a non-equivalent control group, with a pre-test and post-test design. The study was intended for a total of 50 students. They were divided into two groups; an experimental group of 25 students and a control group of 25 students. The experimental group participated in inter dental brush education. The education took about 20 minutes, and was provided once a week, for a total of three weeks. To quantify the effect, the two groups were compared in terms of the dental plaque index and the degree of halitosis. Results: Without inter dental brush education, or a test for homogeneity, in the sense of exact equivalence of the dental plaque index and the degree of halitosis between the experimental and the control group, was supported. (p>.799, p>.876). 1) The first hypothesis, "The experimental group, who participated in inter dental brush education, would reveal a lower dental plaque indices than the control group", was supported (t=5.78, p<.001). 2) The second hypothesis, "The experimental group, who participated in inter dental brush education, would reveal a lower degrees of halitosis than the control group", was supported (t=4.49, p<.001). Conclusion: The proposed inter dental brush education is effective in improving the dental plaque index and the degree of halitosis for elementary school students.

ART1 Algorithm by Using Enhanced Similarity Test and Dynamical Vigilance Threshold (개선된 유사성 측정 방법과 동적인 경계 변수를 이용한 ART1 알고리즘)

  • 문정욱;김광백
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.7 no.6
    • /
    • pp.1318-1324
    • /
    • 2003
  • There are two problems in the conventional ART1 algorithm. One is in similarity testing method of the conventional ART1 between input patterns and stored patterns. The other is that vigilance threshold of conventional ART1 influences the number of clusters and the rate of recognition. In this paper, new similarity testing method and dynamical vigilance threshold method are proposed to solve these problems. The former is similarity test method using the rate of norm of exclusive-NOR between input patterns and stored patterns and the rate of nodes have equivalence value, and the latter method dynamically controls vigilance threshold to similarity using fuzzy operations and the sum operation of Yager. To check the performance of new methods, we used 26 alphabet characters and nosed characters. In experiment results, the proposed methods are better than the conventional methods in ART1, because the proposed methods are less sensitive than the conventional methods for initial vigilance and the recognition rate of the proposed methods is higher than that of the conventional methods.

A Study on the Direct Discharge Test for Verifying Design Concentration and Soaking Time for CO2 Fire Extinguishing System of Total Flooding (전역방출방식 CO2 소화설비의 설계농도 및 유지시간 검증을 위한 직접방사실험에 관한 연구)

  • Lee, Se-Myeoung;Moon, Sung-Woong;Ryu, Sang-Hoon
    • Fire Science and Engineering
    • /
    • v.26 no.6
    • /
    • pp.15-23
    • /
    • 2012
  • Indirect Test Method is often used instead of direct test method in test method for extinguishing performance of $CO_2$ extinguishing facility because of high cost, environment problems and difficulties of procedure. But in the danger facilities for a unit of nation, such as a petrochemical plant, a nuclear power plant, or etc. is better to verify the performance of the extinguishment through direct discharge test. In $CO_2$ extinguishing system for total flooding system installed in dangerous facilities in Korea, each protected area in surface fire and deep-seated fire had selected and verified of extinguishing performance of $CO_2$ extinguishing facilities. To get recognized as extinguishing performance, discharged $CO_2$ concentration to protected area should be equivalence with design concentration standards (NFSC and NFPA). The Design Concentration means that $CO_2$ extinguishing agent is considerate of concentration for percentage of allowance (20 %) from extinguishing concentration which available to control of flame. As test result, surface fire and deep seated fire in protected area is obtained $CO_2$ design concentration and maintained design concentration more than 20 minutes as deep-seated fire. Through this study, we introduced direct discharging test method and decision method. And furthermore, especially in the dangerous facilities as a unit of Nation, we suggested necessity about reliability of extinguishing facilities to use direct test method.

Effects of Hydrogen-enriched LPG Fuelled Engine on Exhaust Emission and Thermal Efficiency [II] (LPG엔진에서 수소첨가가 배기 성능과 열효율에 미치는 영향 [II])

  • Kwon, T.Y.;Kim, J.H.;Choi, G.H.;Chung, Y.J.
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.13 no.4
    • /
    • pp.297-303
    • /
    • 2002
  • The purpose of study is obtaining low-emission and high-efficiency in LPi engine with hydrogen enrichment. The test engine was named variable compression ratio single cylinder engine (VACRE). The fuel supply system provides LPG/hydrogen mixtures based on same heating value. A varied sensors such as crank shaft position sensor (CPS) and hall sensor supplies spark timing data to ignition controller. Displacement of VACRE is $1858.2cm^3$. VACRE was runned 1400rpm with compression ratio 8. Spark timing was set MBT without knocking. Relative air-fuel ratio($\lambda$) of this work was varied between 0,8 and 1.5.

Punching Fracture Experiments and Simulations of Unstiffened and Stiffened Panels for Ships and Offshore Structures

  • Park, Sung-Ju;Choung, Joonmo
    • Journal of Ocean Engineering and Technology
    • /
    • v.34 no.3
    • /
    • pp.155-166
    • /
    • 2020
  • Ductile fracture prediction is critical for the reasonable damage extent assessment of ships and offshore structures subjected to accidental loads, such as ship collisions and groundings. A fracture model combining the Hosford-Coulomb ductile fracture model with the domain of solid-to-shell equivalence model (HC-SDDE), was used in fracture simulations based on shell elements for the punching fracture experiments of unstiffened and stiffened panels. The flow stress and ductile fracture characteristics of JIS G3131 SPHC steel were identified through tension tests for flat bar, notched tension bar, central hole tension bar, plane strain tension bar, and pure shear bar specimens. Punching fracture tests for unstiffened and stiffened panels are conducted to validate the presented HC-DSSE model. The calibrated fracture model is implemented in a user-defined material subroutine. The force-indentation curves and final damage extents obtained from the simulations are compared with experimental results. The HC-DSSE fracture model provides reasonable estimations in terms of force-indentation paths and residual damage extents.

$CO_2^*$ Background Effect on $OH^*$ and $CH^*$ Chemiluminescence Intensities in a Gas Turbine Combustor (가스터빈 연소기에서 $CO_2^*$ 배경 강도가 $OH^*$$CH^*$ 화학 발광 강도에 미치는 영향)

  • Kim, Dae-Sik;Lee, Jong-Guen
    • Journal of the Korean Society of Combustion
    • /
    • v.15 no.4
    • /
    • pp.37-42
    • /
    • 2010
  • The measurement of heat release rate is of great importance in the study of thermo-acoustic instability occurring in lean premixed combustion and the chemiluminescence emission has been used as an indicator of heat release in combustion instability studies primarily for its relative simplicity. This paper presents results of experimental study of flame chemiluminescence from an atmospheric, swirl-stabilized, turbulent lean premixed flame with a main emphasis on the effect of $CO_2^*$ background level in the $CH^*$ and $OH^*$ band. The test results show that the effect of $CO_2^*$ level in the $CH^*$ band is greater than that in the $OH^*$ band. Also, the background to peak ratio for both $CH^*$ and $OH^*$ bands can be expressed as a function of equivalence ratio, almost regardless of a change in the inlet velocity.