• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.6
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• pp.198-206
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• 1999

An automobile outside rear view mirror system has been analyzed and designed to reduce vibration with a finite element model. model analysis is conducted for the calculation of natural frequencies. harmonic analysis is utilized to estimate the displacements of the glass surface under dynamic loads. The model is verified with the vibration experiment of the parts and the assembled body. The structure of the mirror system is optimized for the robustness defined by the Taguchi concept. At first, many potential design variables are defined. Final design variables are selected based on the amount of contribution on the objective function. That is, sensitive variables are chose. The SN ratio in the Taguchi method is replaced by an objective function with the mean and the standard deviation of the quality characteristic. The defined objective function is appropriate in the structural design in that the vibration displacements are minimized while the robustness is improved.

• Journal of Periodontal and Implant Science
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• v.45 no.1
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• pp.2-7
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• 2015

A fundamental problem in analyzing complex multilevel-structured periodontal data is the violation of independency among the observations, which is an assumption in traditional statistical models (e.g., analysis of variance and ordinary least squares regression). In many cases, aggregation (i.e., mean or sum scores) has been employed to overcome this problem. However, the aggregation approach still exhibits certain limitations, such as a loss of power and detailed information, no cross-level relationship analysis, and the potential for creating an ecological fallacy. In order to handle multilevel-structured data appropriately, mixed effects models have been introduced and employed in dental research using periodontal data. The use of mixed effects models might account for the potential bias due to the violation of the independency assumption as well as provide accurate estimates.

• Korean Journal of Remote Sensing
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• v.24 no.3
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• pp.267-272
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• 2008

Tree species-specific estimates with spacebome high-resolution imagery improve estimation of forest biomass which is needed to predict the long term planning for the sustainable forest management(SFM). This paper is a contribution to develop crown distinguishing coniferous species, Pinus densiflora and Pinus koraiensis, from QuickBird imagery. The proposed feature analysis derived from shape parameters and first and second-order statistical texture features of the same test area were compared for the two species separation and delineation. As expected, initial studies have shown that both formfactor and compactness shape parameters provided the successful differentiating method between the pine species within the compartment for single crown identification from spaceborne high resolution imagery. Another result revealed that the selected texture parameters - the mean, variance, angular second moment(ASM) - in the infrared band image could produce good subset combination of texture features for representing detailed tree crown outline.

• Journal of information and communication convergence engineering
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• v.19 no.4
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• pp.284-289
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• 2021

This study attempted to identify the service satisfaction with the 119 emergency service and the factors that affect it based on the responses of subjects who used the service. Data collection was conducted from February 11 to March 11, 2021, using convenience sampling. A total of 1842 subjects who used emergency medical services using 119 ambulance in 2020 participated. For the collected data, frequency, percentage, mean, and standard deviation were calculated, and t-test, analysis of variance, and multiple regression analysis were performed using SPSS 23.0. Based on these results, to further enhance the satisfaction of users of the 119 emergency service and the quality of emergency medical services, it is important to improve the quality of paramedics through education and systems. In addition, to increase user satisfaction, efficient and systematic communication education is required. The quality of emergency medical services will increase only when communication skills required for explanations and promoting understanding are improved.

• Journal of Environmental Science International
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• v.26 no.11
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• pp.1297-1306
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• 2017

This study identified physical characteristics and aerosol particle sources of $PM_{10}$ and $PM_{2.5}$ in the industrial complex of Busan Metropolitan City, Korea. Samples of $PM_{10}$, $PM_{2.5}$ and also soil, were collected in several areas during the year of 2012 to investigate elemental composition. A URG cyclone sampler was used for collection. The samples were collected according to each experimental condition, and the analysis method of SEM-EDX was used to determine the concentration of each metallic element. The comparative analysis indicated that their mass concentration ranged from 1% to 3%. The elements in the industrial region that were above 10% were Si, Al, Fe, and Ca. Those below 5% were Na, Mg, and S. The remaining elements (1% of total mass) consisted of elements such as Ni, Co, Br and Pb. Finally, a statistical tool was applied to the elemental results to identify each source for the industrial region. From a principal components analysis (SPSS, Ver 20.0) performed to analyze the possible sources of $PM_{10}$ in the industrial region, five main factors were determined. Factor 1 (Si, Al), which accounted for 15.8% of the total variance, was mostly affected by soil and dust from manufacturing facilities nearby, Factors 2 (Cu, Ni), 3 (Zn, Pb), and 4 (Mn, Fe), which also accounted for some of variance, were mainly related to iron, non-ferrous metals, and other industrial manufacturing sources. Also, five factors determined to access possible sources of $PM_{2.5}$, Factor 1 (Na, S), accounted for 13.5% of the total variance and was affected by sea-salt particles and fuel incineration sources, and Factors 2 (Ti, Mn), 3 (Pb, Cl), 4 (K, Al) also explained significant proportions of the variance. Theses factors mean that the $PM_{2.5}$ emission sources may be considered as sources of incineration, and metals, and non-ferrous manufacturing industries.

• The Journal of Korean Academic Society of Nursing Education
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• v.20 no.3
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• pp.413-423
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• 2014

Purpose: The purpose of this study was to investigate the relations among emotional intelligence, interpersonal relationship, and job satisfaction among clinical nurses. Methods: Data were collected from 315 nurses who had worked for more than 6 months at five general hospitals by a self-reported questionnaire. The collected data were analyzed with descriptive statistics, t-test, ANOVA, Scheffe-test, Pearson's correlation, and hierarchial regression using SPSS 18.0 program. Results: The mean score of emotional intelligence was 3.42 and the score of self emotional appraisal was the highest. The mean score of interpersonal relationship was 3.44 and the score of intimacy was the highest. The mean score of job satisfaction was 3.04. Emotional intelligence and interpersonal relationship were positively correlated with the job satisfaction. Hierarchial multiple regression analysis showed that use of emotion was the main factor of affecting job satisfaction, which explained 30.8% of the variance for the nurses' job satisfaction together with intimacy, regulation of emotion, position, and monthly salary. Conclusion: These findings indicated that emotional intelligence and interpersonal relationship, especially use and control of emotion and intimacy contributed to nurses' job satisfaction. It is necessary to develop and implement the program for increasing emotional intelligence and interpersonal relationship for improving job satisfaction.

• Korean Journal of Applied Biomechanics
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• v.28 no.3
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• pp.159-164
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• 2018

Objective: The aims of this study were to determine the impact peak force and kinematic variables in running speed and investigate the relationship between them. Method: Thirty-nine male heel strike runners ($mean\;age=21.7{\pm}1.6y$, $mean\;mass=72.5{\pm}8.7kg$, $mean\;height=176.6{\pm}6.1cm$) were recruited in this investigation. The impact peak forces during treadmill running were assessed, and the kinematic variables were computed using three-dimensional data collected using eight infrared cameras (Oqus 300, Qualisys, Sweden). One-way analysis of variance ANOVAwas used to investigate the influence of the running speed on the parameters, and Pearson's partial correlation was used to investigate the relationship between the impact peak force and kinematic variables. Results: The running speed affected the impact peak force, stride length, stride frequency, and kinematic variables during the stride phase and the foot angle at heel contact; however, it did not affect the ankle and knee joint angles in the sagittal plane at heel contact. No significant correlation was noted between the impact peak force and kinematic variables in constantrunning speed. Conclusion: Increasing ankle and knee joint angles at heel contact may not be related to the mechanism behind reducing the impact peak force during treadmill running at constant speed.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.5
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• pp.338-347
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• 2005

A computer-based low back muscle evaluation system was designed to simultaneously acquire, process, display, quantify, and correlate electromyographic(EMG) activity with muscle force, and range of motion(ROM) in the lumbar muscle of human. This integrated multi-channel system was designed around notebook PC. Each channel consisted of a time and frequency domain block, and T-F(time-frequency) domain block. The captured data in each channel was used to display and Quantify : raw EMG, histogram, zero crossing, turn, RMS(root mean square), variance, mean, power spectrum, median frequency, mean frequency, wavelet transform, Wigner-Ville distribution, Choi-Williams distribution, and Cohen-Posch distribution. To evaluate the performance of the designed system, the static and dynamic contraction experiments from lumbar(waist) level of human were done. The experiment performed in five subjects, and various parameters were tested and compared. This system could equally well be modified to allow acquisition, processing, and analysis of EMG signals in other studies and applications.

• Korean Journal of Health Education and Promotion
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• v.21 no.2
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• pp.187-198
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• 2004

The purpose of this study was to investigate knowledge, attitudes and the ability of women toward breast self-examination and to identify factors that may influence the ability of breast examination. The subjects for this study were 105 women in a community health center located in Busan. Data was collected during the period from September I to 20, 2002 by means of a structured questionnaire. The data was analyzed using the SPSS WIN 10.0 program and included descriptive statistics, Pearson correlation coefficient and stepwise multiple regression. The results of study are as follows： 1. The mean knowledge score for the total sample was 9.62 and the mean attitude score was 62.95. The mean self- practice score was 5.79. 2. Women's knowledge about breast self-examination was significantly related to attitudes and the ability of women toward breast self-examination (p＜0.05). 3. The ability of women toward breast self-examination was significantly related to attitudes about breast self-examination (p＜0.05). 4. According to the results of stepwise multiple regression analysis, factors affecting women's ability of breast self-examination were practice of breast self-examination and level of education and explained 19.7％ of variance. From the results of this study it can be said that women need to be taught proper breast self-examination so that they can become more proficient in detecting breast abnormalities.

• Toxicological Research
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• v.30 no.3
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• pp.185-191
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• 2014

Statistical methods are frequently used in toxicology, yet it is not clear whether the methods employed by the studies are used consistently and conducted based on sound statistical grounds. The purpose of this paper is to describe statistical methods used in top toxicology journals. More specifically, we sampled 30 papers published in 2014 from Toxicology and Applied Pharmacology, Archives of Toxicology, and Toxicological Science and described methodologies used to provide descriptive and inferential statistics. One hundred thirteen endpoints were observed in those 30 papers, and most studies had sample size less than 10, with the median and the mode being 6 and 3 & 6, respectively. Mean (105/113, 93%) was dominantly used to measure central tendency, and standard error of the mean (64/113, 57%) and standard deviation (39/113, 34%) were used to measure dispersion, while few studies provide justifications regarding why the methods being selected. Inferential statistics were frequently conducted (93/113, 82%), with one-way ANOVA being most popular (52/93, 56%), yet few studies conducted either normality or equal variance test. These results suggest that more consistent and appropriate use of statistical method is necessary which may enhance the role of toxicology in public health.