• Journal of Mechanical Science and Technology
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• 제18권12호
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• pp.2182-2189
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• 2004

In the recent years, environmentally conscious design and manufacturing technologies have attracted considerable attention. The coolants, lubricants, solvents, metallic chips and discarded tools from manufacturing operations will harm our environment and the earth's ecosystem. In the present work, the Tukey method of multiple comparisons is used to select the minimum level of coolant required in a turning process. The amount of coolant is varied in 270 designed experiments and the parameters cutting temperature, surface roughness, and specific cutting energy are carefully evaluated. The effects of coolant mix ratio as well as the amount of coolant on the turning process are studied in the present work. The cutting temperature and surface roughness for different quantity of coolant are investigated by analysis of variance (ANOVA) - test and a multiple comparison method. ANOVA-test results signify that the average tool temperature and surface roughness depend on the amount of coolant. Based on Tukey's Honestly Significant Difference (HSD) method, one of the multiple comparison methods, the minimum level of coolant is 1.0 L/min with 2% mix ratio in the aspect of controlling tool temperature. F-test concludes that the amount of coolant used does not have any significant effect on specific cutting energy. Finally, Tukey method ascertains that 0.5 L/min with 6% mix ratio is the minimum level of coolant required in turning process without any serious degradation of the surface finish. Considering all aspects of cutting, the minimum coolant required is 1.0 L/min with 6% mix ratio. It is merely half the coolant currently used i.e. 2.0 L/min with 10% mix ratio. Minimal use of coolant not only economically desirable for reducing manufacturing cost but also it imparts fewer hazards to human health. Also, sparing use of coolant will eventually transform the turning process into a more environment-conscious manufacturing process.

• Journal of Pharmaceutical Investigation
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• 제24권2호
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• pp.49-55
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• 1994

Bioequivalence test of commercially available rifampicin capsules was performed. Sixteen volunteers were divided into 2 groups and the reference and test drug were given orally (450 mg) by cross-over design. Statistical evaluation of AUC, $C_{max}\;and\;T_{max}$ involved an analysis of variance (ANOVA). The differences of mean value in AUC, $C_{max}\;and\;T_{max}$ between the reference and test drug were within 20% with reference drug. ANOVA showed no significant differences for ‘between group’, ‘drug’ and ‘period’, but not for ‘between subjects’. The power of test $(1-{\beta})\;of\;AUC\;and\;$C_{max}$ was larger than 0.8 and the confidence of bioavailability was $within\;{\pm}20%$. From these results, it was concluded that the two preparations were bioequivalent for AUC and $C_{max}$, but was not for $T_{max}$.

• 약학회지
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• 제33권4호
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• pp.229-236
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• 1989

Even though two different preparations are chemically equivalent, the variance of bioavailability differenciates the clinical effect of preparations, so that the preparations need to be evaluated by comparing bioavailability in vivo as well as chemical equivalence. In this study, bioequivalence tests of commercially available isoniazid tablets A, B, C and D (standard) were performed to give some guidelines to bioequivalence test. The bioavailability parameters obtained by drug administeration were statistically analyzed. Statistical evaluation of the data involved an analysis of variance for a cross over design. Cross over design was employed with 8 healthy volunteers. The results were within 20% difference of mean value in the AUC, Cmax, Tmax and amount of urinary excretion (Au) between standard and isoniazid tablets. The results of ANOVA showed no significant differences for 'group or sequence', but almost not for 'between subjects'. The tablet. A, B and D were within 20 min, but tablet C was within 50 min. Tablet A was biologically equivalent in the Au. tablet B biologically equivalent in the Au and AUC. Tablet C was biologically equivalent in the Au. The relationship between the dissolution rate and Au was significant.

• 한국공작기계학회논문집
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• 제17권4호
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• pp.133-139
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• 2008

With the increasing demand for higher production quality and growing competition in the global market, coordinate measuring machine(CMM) has been widely used in industry to improve the efficiency and effectiveness of measurement. In this paper the performance evaluation of coordinate measuring machine is proposed using design of experiments. A factorial design is applied to carry out the performance test proposed by ISO 10360 with a length bar and to investigate CMM measurement errors associated to orientation and length in the work volume. The determination of the significance of effects in an experiment is made through the analysis of variance(ANOVA). The results show that the proposed method is suitable to analyze the factors which affect the CMM measurement performance.

• 대한가정학회지
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• 제43권5호
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• pp.93-105
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• 2005

This study focused on the development of scales measuring the characteristics related to appearance management behaviors of businessmen for on-line image consulting. The purposes of this study were, 1) to develop a tool which can measure the ideal image, 2) to develop a tool which can measure personality, and 3) to develop a scale measuring the physical characteristics and body cathexis. The data were collected from 380 businessmen in Seoul, Korea and were analyzed by frequency, factor analysis, reliability test, cluster analysis, correlation analysis, one-wav ANOVA and Duncan test. The results from this study were as follows .1)Five factors of the ideal image were identified: stylish, able, active, neat/confident and easy. The total variance was 74.29$\%$ and Cronbach's alpha of the 5 factors ranged from .74-.90. One item was selected to represent each factor. 2) Five factors of personality were identified: preference of social function, sociable, dynamic, achievement-motivated, and success-oriented. The totai variance was 60.63$\%$ and Cronbach's alpha ranged from .56-.83. One item was selected to represent each factor. 3) Five factors of body cathexis were identified: satisfaction with girth, length, physique, nose and eyes. The total variance was 73_46$\%$ and Cronbach's alpha ranged from .68-.85.

• 대한치과의사협회지
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• 제52권9호
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• pp.558-569
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• 2014

Sample size determination is critical, but not easy to do. Sample size defined as the number of observations in a sample to be studied should be big enough to have a high likelihood of detecting a true difference between groups. Practical procedure for determining sample size, using $G^*$power and previous dental articles, was shown in this study. Examples involving independent t-test, paired t-test, one-way analysis of variance(ANOVA), and one-way repeated-measures(RM) ANOVA were used. The purpose of this study is to enable researchers with non-statistical backgrounds to use in practice freely available statistical software G*power to determine sample size and power.

• Journal of Pharmaceutical Investigation
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• 제24권2호
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• pp.67-72
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• 1994

Bioequivalence (BE) test of biphenyl dimethyl dicarboxylate (DDB) tablets was performed. Normal healthy male volunteers (n = 20) were randomly divided into 2 groups, and reference $(Nissel{\circledR})$ and test $(Livital{\circledR})$ tablets of DDB $(25mg{\times}8\;Tab.\;= \;200\;mg)$ were given orally by balanced two-period cross-over design. The serum concentration was determined by high performance liquid chromatography. The pharmacokinetic parameters, AUC, $C_{max}$, and $T_{max}$ obtained after drug administration were statistically analyzed. Statistical evaluation of the data involved an analysis of variance (ANOVA) for cross-over design. The results were within 20% differences of mean value in AUC, $C_{max}$, and $T_{max}$ between reference and test tablets. The results of ANOVA showed no significant differences for "between group or subject" and "period". The test tablet was bioequivalent with the reference tablet in the AUC, $C_{max}$, and $T_{max}$.

• 대한가정학회지
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• 제36권10호
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• pp.79-88
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• 1998

The purpose of this study is to identify environmental perception of clothing consumption behavior taking socioo-economic variables into account. An instrument, based on previous research was administered to 213 housewives in Taegu area. In analyzing the data, factor analysis, t-test, ANOVA, regression analysis were used. The finding of this indicated that the environmental perception of clothing consumption were significant in purchasing, managing, and disposal of clothing. Among socio-economics variables, income and educational level were found to be significant in explaining the variance of enviromental perception behavior of clothing consumption. The important results of this study are discussed and implications are provided.

• Advances in Computational Design
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• 제4권1호
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• pp.1-13
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• 2019

Recent generations of smartphones offer accelerometer sensors as a standard feature. While this has led to the development of a number of related applications (apps), there has been no study on their comparative or individual performance against a benchmark. This paper investigates the comparative performance of a number of smartphone accelerometer apps amongst themselves and to a calibrated benchmark accelerometer. A total of 12 apps were selected for testing out of 90 following an initial review. The selected apps were subjected to sinusoidal vibration testing of varying frequency and the response of each compared against the calibrated baseline accelerometer. The performance of apps was quantified using analysis of variance (ANOVA) and test of significance was carried out. The apps were then compared for a realistic dynamic scenario of measuring the acceleration response of a bridge due to the passage of a French Train $\grave{a}$ Grande Vitesse (TGV) in a laboratory environment.

• 한국콘텐츠학회논문지
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• 제21권3호
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• pp.664-675
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• 2021

본 연구에서는 스트릿 댄스 학원을 선택하는 일반인과 스트릿 댄스 전공자들을 대상으로 한 스트릿 댄스 학원 선택속성을 분석하고자 한다. 나아가 스트릿 댄스에 대한 인식과 가치를 높이고 스트릿 댄스를 전문 교육하는 학원들의 발전에 필요한 자료를 제공하는데 목적이 있다. 이러한 목적을 달성하기 위해서 스트릿 댄스 학원에 다니고 있는 300명의 스트릿 댄스 학습자들을 대상으로 설문조사를 실시하였다. 수집된 자료는 SPSS18.0 프로그램을 사용하여 빈도분석, 신뢰도 분석(Reliability test), 상관관계 분석(Correlation Analysis), 일원 분산분석(One-Way Analysis of Variance: ANOVA)을 실시하였다.연구 결과를 종합하여 보면, 스트릿 댄스 학원의 학습자 선택속성 구성 요소 중 교육 프로그램, 서비스, 홍보환경이 가장 중요한 선택 속성요인으로 파악된 반면에 가격요인의 중요성은 비교적 낮은 인식으로 파악되었다.