• Proceedings of the KSME Conference
• /
• 2007.05b
• /
• pp.3128-3133
• /
• 2007

The mixing method of water and chemicals is significant in a small-scale water supply system because drinking water should be supplied with a certain quantity of remaining chemicals maintained. In the present study, the concentration distribution and the mixing index were obtained from four models, which were to find out the optimal mixing method of water and chemicals. The two models brought the good mixing effects out of the four, one for providing chemicals from the center of water supply pipe and the other for setting up the semicircle block at the downstream of the chemicals-providing pipe. As a result, the mixing effect was found out to be increased due to the diffusion and the disturbance of flows. In conclusion, these results are expected to contribute to designing the optimal mixing system.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.23 no.12
• /
• pp.1535-1541
• /
• 2019

To carry out safe and rapid decontamination in radiological accident areas, acquisition of various information on radiation sources is needed. In particular, to figure out the location and distribution of radiation sources is essential for rapid follow-up and removal of contaminants as well as minimizing worker damage. The radiation distribution detection device is used to obtain the position and distribution information of the radiation source. In the case of a radiation distribution detection device, a detection sensor unit is generally composed of a single sensor, and the detection range is limited due to the physical characteristics of the single sensor. We applied a calibration detector for controlling the detection sensitivity of a single sensor for radiation detection and improved the limited detection range of radiation dose rate. Also, gamma irradiation test confirmed the improvement of radiation distribution detection range.

• Journal of Distribution Science
• /
• v.14 no.8
• /
• pp.9-21
• /
• 2016

Purpose - This research analyzes the impact of motivations to dine out and selected attributes of customers on customer satisfaction and loyalty. Based on collected data, this study aims to suggest effective marketing strategies to help manage traditional Korean food restaurants. Research design, data, and methodology - The data were collected from the customers who visited traditional Korean food restaurants in Jeon-Ju for two months from December, 2015. The available data were 402 from collected 450 customers' data and they were analyzed by using SPSS 19.0. Result - These are the results of data analysis. First, environmental, personal and perceived factors influence on the motivations to dine out at Korean food restaurants which affect customer satisfaction. Next, selected attributes from Korean food restaurants have impacts on customer satisfaction. Third, motivations to dine out Korean food restaurants affect customer loyalty. Moreover, physical environments, curiosity and need satisfactions, which are the selected attributes, have impacts on customer loyalty. Lastly, it has been identified that customer satisfaction in Korean food restaurants influences customer loyalty. Conclusions - Satisfaction and good brand image of Jeon-Ju will increase customers' intention to revisit. This study has found that high customer satisfaction leads to re-visitation.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.31 no.5
• /
• pp.278-293
• /
• 2019

The joint distribution of wave height and period has been maltreated despite of its great engineering value due to the absence of any analytical model for wave period, and as a result, no consensus has been reached about the effect of nonlinearity on these joint distribution. On the other hand, there was a great deal of efforts to study the effects of non-linearity on the wave height distribution over the last decades, and big strides has been made. However, these achievements has not been extended to the joint distribution of wave height and period. In this rationale, we first express the joint distribution of wave height and period as the product of the marginal distribution of wave heights with the conditional distribution of associated periods, and proceed to derive the joint distribution of wave heights and periods utilizing the models of Longuet-Higgins (1975, 1983), and Cavanie et al. (1976) for conditional distribution of wave periods, and height distribution derived in this study. The verification was carried out using numerically simulated data based on the Wallops spectrum, and the nonlinear wave data obtained via the numerical simulation of random waves approaching toward the uniform beach of 1:15 slope. It turns out that the joint distribution based on the height distribution for finite banded nonlinear waves, and Cavanie et al.'s model (1976) is most promising.

• Journal of Environmental Science International
• /
• v.12 no.12
• /
• pp.1261-1267
• /
• 2003

On the basis of the distribution of particle size measured by laser diffraction spectrometers, this research was carried out to investigate the characteristics of mist removal with the change of operating condition in the plasma reactor of impulse streamer corona. The operating parameters in this experiment were power of impulse streamer corona, gas velocity, impulse generation time, gas temperature, and SOx/NOx concentration. The collection efficiency T(d) was estimated by the distribution of particle size in the collection zone through the advanced model.

• Journal of applied mathematics & informatics
• /
• v.17 no.1_2_3
• /
• pp.747-757
• /
• 2005

A physical variable is customarily thought of as a function. Another way of describing a physical variable is to specify it as a functional, whose special type is called a distribution. It turns out that the distribution concept provide a better mechanism for analyzing certain physical phenomena than does the function concept. By using wavelets with high regularity we give a resolution of functions with slow growth.

• Journal of Distribution Science
• /
• v.15 no.9
• /
• pp.17-26
• /
• 2017

Purpose - This study aims to present ways to secure capable employees by examining key factors of internal marketing applicable to the jewelry distribution business and analyzing the relations among organizational commitment, job satisfaction, and turnover intentions among employees who play important roles in jewelry distributors. Research Design, data, and methodology - To examine these research models, samples were collected from 210 individuals working in jewelry distribution companies. The analysis was conducted by the use of a questionnaire method among employees in jewelry distribution companies. SPSS 18.0 were utilized for data analysis. Results - Among internal marketing components of jewelry distribution companies, the two factors - management support and reward system - have positive (+) effect on organizational commitment and while internal communication and education/training have negative (-) effect on employees' turnover intention. Jewelry distribution company employees' job satisfaction and organizational commitment have negative (-) effect on their turnover intention. Conclusions - This is an exploratory study that aims to find out ways to prevent employee turnover in the perspective of jewelry distribution companies' organizational measure - internal marketing. The future study needs to present more sophisticated strategies of internal marketing based on in-depth analysis of specific causes that make employees at jewelry distribution companies leave the occupations.

• Steel and Composite Structures
• /
• v.38 no.4
• /
• pp.399-414
• /
• 2021

This paper aims to verify the feasibility of rubber rings to mitigate the shear concentration in perfobond connector (PBL) groups. Firstly, modified push-out tests for five specimens with four holes were conducted to investigate the effects of rubber rings on the shear mechanism of PBL groups. The test results showed that by employing rubber rings on partial holes, more shear forces were distributed to the holes without rubber rings. The rubber rings significantly improved the slip ability of the specimens, and the ductility of PBL groups is dependent on the number and thickness of rubber rings. Subsequently, three-dimensional numerical models were established and validated by the experimental results. According to the plastic strain distribution in concrete dowels, the action principle of rubber rings in PBL groups was explained. Furthermore, the parametric study was conducted to investigate the influential factors on shear distributions, including the width of steel plates, the hole spacing, the number of holes, the rubber ring thickness, and the positions of rubber rings. The parametric analysis results showed that the redistribution of shear forces is significantly affected by the rubber rings with the smallest thickness. By properly employing rubber rings in PBL groups, the shear forces of holes are more even. Finally, an analytical model for PBL groups with rubber rings was proposed to predict the shear distribution at the serviceability stage.

• Journal of Soil and Groundwater Environment
• /
• v.23 no.1
• /
• pp.41-53
• /
• 2018

Comprehensive statistical analysis for the 127 groundwater monitoring stations in Jeju Island during 2005~2015 was carried out for the re-establishment of management groundwater level. Three probability distribution functions such as normal distibution, GEV (General Extreme Value) distribution, and Gumbel distribution were applied and the maximum likelihood method was used for parameter estimation of each distribution. AIC (Akaike information criterion) was calculated based on the estimated parameters to determine the proper probability distribution for all 127 stations. The results showed that normal distribution and Gumble distribution were found in 11 stations. Whereas GEV distribution were found in 105 stations, which covered most of groundwater monitoring stations. Therefore, confidence levels should be established in accord with the proper probability distribution when groundwater level management is determined.

• Geomechanics and Engineering
• /
• v.5 no.5
• /
• pp.485-497
• /
• 2013

The factor of safety is the most common measure of the safety margin for slopes. When the traditionally defined factor is used in kinematic approach of limit analysis, calculations can become elaborate, and iterative methods have to be used. To avoid this inconvenience, the safety factor was defined in terms of the work rates that are part of the work balance equation used in limit analysis. It was demonstrated for two simple slopes that the safety factors calculated according to the new definition fall close to those calculated using the traditional definition. Statistical analysis was carried out to find out whether, given normal distribution of the strength parameters, the distribution of the safety factor can be approximated with a well-defined probability density function. Knowing this function would make it convenient to calculate the probability of failure. The results indicated that the normal distribution could be used for low internal friction angle (up to about $16^{\circ}$) and the Johnson distribution could be used for larger angles ${\phi}$. The data limited to two simple slopes, however, does not allow assuming these distributions a priori for other slopes.