• Title/Summary/Keyword: ANOVA(analysis of variance)

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A Study on the Working Condition Effecting on the Maximum Working Temperature and Surface Roughness in Side Wall End Milling Using Design of Experiment (실험계획법을 이용한 엔드밀 가공 시 최대가공온도와 표면조도에 미치는 가공조건에 관한 연구)

  • Hong, Do-Kwan;Ahn, Chan-Woo;Baek, Hwang-Soon;Choi, Seok-Chang;Park, Il-Soo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.8 no.3
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    • pp.46-53
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    • 2009
  • To find the working condition is one of the important factors in precision machining. In this study, we analyzed maximum working temperature by infra-red camera and surface roughness in side wall end milling using design of experiment (DOE): RSM(response surface methodology), ANOM(analysis of means) and ANOVA(analysis of variance) by table of orthogonal array. ANOM and ANOVA are well adapted to select sensitivity of design variables for maximum working temperature and surface roughness. The effective design variables and their levels should be determined using ANOM, ANOVA. RSM is presented 2nd order approximation polynomial of maximum working temperature and surface roughness is composed with design variables. Therefore, it is expected that the proposed procedure using design of experiment : table of orthogonal array, ANOM, ANOVA and RSM can be easily utilized to solve the problem of working condition.

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Comparison of smartphone accelerometer applications for structural vibration monitoring

  • Cahill, Paul;Quirk, Lucy;Dewan, Priyanshu;Pakrashi, Vikram
    • Advances in Computational Design
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    • v.4 no.1
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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.

A Basic Study on City Gas Consumption Difference according to the exclusive dwelling area

  • Kim, Sang Ho;Yang, Sungpil;Yu, Yeongjin;Son, Kiyoung
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.732-733
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    • 2015
  • Currently, since the total energy amount has been increased continuously, the effort for energy efficiency of apartment building is necessary. Although the previous studies have been focused on the issue. Almost studies are about the simulation by applying the energy analysis tools and a lack of studies have been conducted the data analysis about real city gas amount of apartment building. Therefore, the objective of this study is to analyze the city gas consumption difference according to the exclusive dwelling in apartment building. To address this issue, the descriptive, correlation, analysis of variance (ANOVA) statistics are used in this study. As a result, in the case of annual total amount, the city gas is increased as the size of the exclusive dwelling area is increased. In the future, the findings of this study can be used as a basic material to develop the prediction model of city gas in apartment building.

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Statistical Analysis of Chlorine Residual in Korean Drinking Water (국내정수장의 잔류염소농도에 대한 조사연구)

  • Sohn, Jinsik;Kang, Hyosoon
    • Journal of Korean Society of Water and Wastewater
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    • v.20 no.2
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    • pp.281-287
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    • 2006
  • Maintaining adequate chlorine residual is crucial in water treatment facilities, Treatment technique, newly promulgated regulation, requires sufficient disinfection in order to control more resistant microorganisms such as Viruses and Giardia lamblia. Each water treatment plant should report various water qualities including chlorine residual and disinfection by-products, thus plenty of data has been generated. Even though statistical analysis using these data are forced to investigate the status and effect of water qualities in water facilities very few researches have been performed in korea. This study performed statistical analysis of chlorine residual during three years in Korean drinking water. The average chlorine residual concentrations were 0.701mg/L, 0.738mg/L, 0.763mg/L in 2002, 2003, 2004, respectively. Monthly variations of chlorine residual was not significant. ANOVA result showed that yearly variance of chlorine residual is different in only less than $5000m^3/day$ of water treatment capacity. The statistical analysis can help government to establish new regulation with scientific basis.

Design of Steering System Considering Interaction Effects in Discrete Design Space (교호작용을 고려한 이산설계 공간에서의 Steering System 설계)

  • Kwon, Woo-Sung;Park, Kwang-Seo;Kim, Young-Ho;Kim, In-Dong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.05a
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    • pp.786-792
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    • 2006
  • The design of experiment(DOE) with orthogonal arrays is adopted when the engineering design is needed in a discrete design space. In this research, a design process with orthogonal array is peformed to obtain the optimum design which satisfy the frequency target of the steering system. The optimum design is determined from the analysis of means(ANOM) and sensitivity information about design variables is evaluated by the analysis of variance(ANOVA). Interactions between design variables are investigated to achieve additivity which should be valid in using orthogonal array. It is shown that when strong interactions exist, the DOE process with orthogonal array considering interaction is introduced to find out optimum design.

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Relationship between Perception for Appraisal of Perioperative Nurses and Performance and Organizational Commitment (수술실 간호사의 성과 평가에 대한 인식이 조직몰입 및 성과에 미치는 영향)

  • Kang, Kyoung-Hee;Park, Sung-Ae
    • Journal of Korean Academy of Nursing Administration
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    • v.17 no.2
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    • pp.189-197
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    • 2011
  • Purpose: This study was an analysis of the relationship between perception for appraisal of staff nurses in operating rooms and performance and organizational commitment. Method: The survey was conducted with 176 staff nurses in operating rooms in 2 hospitals in Seoul. Data were analyzed using frequency, one-way ANOVA, Pearson correlation analysis, and stepwise multiple regression. Result: 1. Perception for appraisal including accuracy and justice was significantly related to organizational commitment (r=.496, P=.000). Perception for appraisal including accuracy and justice was slightly related to performance (r=.220, P=.003). 2. In order to determine the percentage of the variance of performance and organizational commitment that could be predicted by perception for appraisal, perception for appraisal was entered in the regression equation. Accuracy accounted for 25% of the variance in the organizational commitment. To determine the percentage of the variance of performance that could be predicted by perception for appraisal and organizational commitment, the perception for appraisal and organizational commitment were entered in the regression equation. Organizational commitment accounted for 21% of the variance in the performance. Consequently accuracy predicted organizational commitment. Organizational commitment predicted performance. Conclusions: Findings indicate the need to increase accuracy of performance appraisal to promote organizational commitment and performance in perioperative nurses.

Analysis of Cutting Properties with Reference to Amount of Coolant used in an Environment-Conscious Turning Process

  • Yang, Seung-Han;Lee, Young-Moon;Kim, Young-Suk
    • Journal of Mechanical Science and Technology
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    • v.18 no.12
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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.

The Knowledge about Savings of Customers Who Utilize Investiment Trust Company and Related Factors (투자신탁 이용 고객의 저축 상품에 관한 지식과 영향변수)

  • 이연숙;강연아
    • Journal of Family Resource Management and Policy Review
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    • v.4 no.1
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    • pp.15-28
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    • 2000
  • The purpose of this study was to examine the knowledge about savings of customers who utilize Investment Trust Company and to analyze the factors affecting it. The data for the analysis were collected by structured questionnaires and consisted of 191 customers who utilize Investment Trust Company. Descriptive. Descriptive Statistics including percentage, frequency, means, and standard derivation, t-test, one-way ANOVA with Scheffe test, multiple regression analysis were used to analyze the data. The following is a summary of major findings. 1) The customers knowledge about savings showed generally low-level. Especially the knowledge about tax and regulation of savings were the areas shown the lowest level. 2) The age, marital status, education and occupation of customers and total period of utilizing company were the factors affecting the knowledge of customers in the one-way ANOVA analysis. 3) The result of regression analysis indicated that age of customers and total periods of utilizing company were the significant predictors of customers’knowledge. These two variables explained 25.77% of variance of customers’knowledge about savings.

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A Study on the Accomplishment of Lecture Evaluation in University (대학 강의평가 수행에 관한 연구)

  • 정진식
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.10 no.1
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    • pp.93-115
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    • 1999
  • This Study is the summary of studies in analysis of‘Lecture Evaluation’made at H university where such evaluation for every course established has been carried out since 1990. This contains the contents of questionnaire drawn up through OMR scanner which has 7 fields with 10 items respectively. to investigate the general direction of the results, results of evaluation by lectures, different results of evaluation by fields, and the like. I applied such techniques of statistical analysis as T-test, analysis of variance table(Anova-table), and Regression analysis to examine the most important factor of successful lecturing.

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The Optimization Analysis for the Selection of Cutting Parameters in Turning Operation

  • Hong, Min-Sung;Lian, Zhe-Man
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.10 no.3
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    • pp.97-103
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    • 2001
  • This paper has focused on the Optimization of the cutting parameters for urning operation based on the Taguchi method. Four cutting parameters. nemely, cutting speed, feed depth of cut and nose radius are optimized with consideration of the surface roughness. The design and analysis of experiments are conducted to study the performance characteristic. The effects of these parameters on the surface roughness have been investigated using signal-to-noise(S/N) ratio and analy-sis of variance(ANOVA). The experiments have been performed using coated tungsten carbide inserts without any cutting fluid. Experimental results illustrate the effectiveness of this approach.

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