• Journal of the Korean Society of Safety
• /
• v.22 no.4
• /
• pp.83-89
• /
• 2007

This study is perform to improve the current point at issue of the non-regular employees, comparing the safety and health consciousness of between the regular employees and non-regular employees in manufacturing factory. The investigation is carried out using the statistical analysis. The study presents that most of the non-regular employees answer in the negative the current job satisfaction, work load, work risk, concern on the safety and health, education, occupational safety and health system than the regular employees. For the improvement of these problems, the government's safety and health policy should be changed and acknowledgement of the employer and employee on the safety and health should be improved.

• Bulletin of the Korean Mathematical Society
• /
• v.54 no.2
• /
• pp.507-519
• /
• 2017

We present an upper bound on the Cheeger constant of a distance-regular graph. Recently, the authors found an upper bound on the Cheeger constant of distance-regular graph under a certain restriction in their previous work. Our new bound in the current paper is much better than the previous bound, and it is a general bound with no restriction. We point out that our bound is explicitly computable by using the valencies and the intersection matrix of a distance-regular graph. As a major tool, we use the discrete Green's function, which is defined as the inverse of ${\beta}$-Laplacian for some positive real number ${\beta}$. We present some examples of distance-regular graphs, where we compute our upper bound on their Cheeger constants.

• Communications of the Korean Mathematical Society
• /
• v.39 no.2
• /
• pp.363-372
• /
• 2024

In this paper, we introduce a weak version of coherent that we call regular coherent property. A ring is called regular coherent, if every finitely generated regular ideal is finitely presented. We investigate the stability of this property under localization and homomorphic image, and its transfer to various contexts of constructions such as trivial ring extensions, pullbacks and amalgamated. Our results generate examples which enrich the current literature with new and original families of rings that satisfy this property.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.33 no.2
• /
• pp.135-140
• /
• 2020

An experimental study was conducted using the tracking wheel test (IEC 62217) method for evaluating the performance of insulator materials, in particular ethylene propylene diene monomer (EPDM) and silicone rubber. In addition, we studied the tracking characteristics resulting from applying the same method for the shape of the insulator housing, that is, the performance of regular and alternating sheds. The evaluation parameters were leakage current, surface characteristics, SEM, EDX, hydrophobicity, and temperature distribution; likewise, we applied the commercial frequency dry (and wet) flashover voltage test. We found that the regular shed had a greater leakage current than the alternating shed and that the recovery of the hydrophobicity in terms of rest time was greater than that of the EPDM in terms of leakage current. All of the regular-shed insulators of silicone rubber had tracking traces and choking on the sheath parting line, while the alternating shed showed only choking at the interface but no tracking traces. Therefore, it can be concluded that the commercial frequency wet flashover voltage of the silicone rubber with regular shed before and after the tracking wheel test is higher than that of the alternating shed.

• Journal of the Korean Society of Food Culture
• /
• v.21 no.4
• /
• pp.388-395
• /
• 2006

The purpose of this study was to analyze the current operating management practices and tourist royalty of restaurants at the tourism provinces in Donghae city. Forty restaurants were surveyed for sales status, customer management, menu management, advertising, marketing strategy and seventy seven tourists replied to the attitudinal and behavioral aspects of customer royalty for regular visiting restaurant. Statistical data analyses were completed using the SPSS/WIN pact(age program for descriptive analysis, paired difference test, t-test, ANOVA, and pearson correlation. The results of quantitative analysis indicated that the average sales per day on a high-demand season were 1,571 thousand won and one on a slack season were 614 thousand won. The average check on a high-demand season(109 persons) and a slack season(38 persons) were significant difference(t=6.834, p<.001). A total of 93.5% of the restaurateurs answered that menu pricing was decided by the owner and 21.7% of the subjects used the only restaurant homepage in the advertising method. A total of 40.6% of the restaurants utilized the only kind service for regular customers and 35.1% of the subjects had no method for them. The results suggest that systematic management policies and marketing strafes for regular customer is very necessary. Also, the correlation between tourists' attitudinal and behavioral aspects of customer royalty for regular visiting restaurant was found out. High correlation was existed between the overall tourists' satisfaction on regular visiting restaurant, the intention to revisit(BCL 1, p<.001), the intention to recommend(BCL 2, p<.001), and indicators of customer royalty. Finally, restaurateurs at the tourism provinces should focus on marketing strategy to keep and improve current customer to rise the tourist royalty.

• 한국신재생에너지학회:학술대회논문집
• /
• 2009.06a
• /
• pp.632-635
• /
• 2009

Nowadays renewable energy has undergone major development, however most renewable energy resources still have demerit which is under the influence of environmental factors that can not be set up the power plants or can not be generated the rated power. To wander from the point of environmental instability, the present paper looks at the tidal current energy which can supply regular electric power. It has an important merit which is more predictable than others, however the place which can be set up is limited and the turbine system must be optimized. The development of the optimized rotor blades design is urgent to obtain regular electric power using the tidal current energy. Therefore, the paper expands on this idea and presents a conceptual design of 100kW horizontal axis rotor blade for the tidal current turbine using blade element momentum (BEM) analysis. The compatibility of horizontal axis tidal turbine (HATT) is verified using a commercial computational fluid dynamics (CFD) code, ANSYS-CFX. This paper presents results of the numerical analysis, such as pressure, streak line and the performance curves with torque data for the inflow of the horizontal axis tidal current turbine (HATT).

• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.527-529
• /
• 2004

This paper researched leakage current characteristics of EHW insulators(36,000lbs) to artificially contaminated clay and kaolin through construction of long-periods testing facility. Insulators were contaminated and classified into the ESDD level(B, C and D) under IEC Pub. 60507 standards method. As a result of tests, leakage current of the heavily contaminated D level to clay was approximately 2,260 $[\muA]$, which is contaminated to kaolin was approximately 3,200 $[\muA]$, during initial rainfall. However after raining, leakage current of naturally washed contamination insulators was lower at approximately 300 $[\muA]$. As regular temperature $20^{\circ}C$, leakage current increased greatly in case humidity density was over $72\%$. But, leakage current was not influenced by temperature variation in case of regular $\%$ humidity.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.16 no.2
• /
• pp.185-193
• /
• 2010

In the present study, wave deformation and wave-induced current were calculated under the regular wave conditions using the Boussinesq model. The model results of the wave deformation showed good agreements with the preceeding laboratory experiments of others. The wave-induced current of the fully developed sea state was calculated. For field application of model, the preceeding field data by others in the real scale of the water area were compared, the numerical result of wave deformation showed a relatively good agreement with the field data. Although the numerical result of wave-induced current was underestimated over the longshore bar developed area, the Boussinesq model is generally suitable to predict the wave-induced current.

• Journal of the Korean Solar Energy Society
• /
• v.32 no.3
• /
• pp.26-32
• /
• 2012

A current compensation method to reduce the mismatch loss in PV systems is proposed as a way to increase the power generation efficiency. A dc-dc converter is used to supply currents to irregular modules in a PV string and is powered from the string output. The converter's voltage conversion ratio is adjusted so that all the modules in the string are operated at the maximum power point. The power rating and size of the converter can be reduced since only the current difference between the regular and irregular module may be supplied. The compensated string shows very little voltage mismatch compared to other regular strings. The validity of the proposed method is verified through a simulation and experiments in a prototype PV system.

• The Journal of Industrial Distribution & Business
• /
• v.8 no.2
• /
• pp.21-31
• /
• 2017

Purpose - The total amount of advanced Corporate Pension Insurance products exceed 148 trillion Korean Won at the end of 2016. For a firm with over 300 employees, when a bill on compulsion of introduction of Corporate Pension Insurance products, currently pending in court, is passed, Corporate Pension shall be an essential. The findings of the paper will provide a guideline for understanding on firm's attributes and its effects towards introduction of Corporate Pension Insurance products. Research design, data, and methodology - The data were collected using statistics of employer panel survey from Korea Labour Institute in 2013. The study analyses a sample survey on 1,775 outstanding enterprises and their HR department among whole corporations in Korea. For analysis of data, empirical testing by Logistic Regression was utilized. Results - As an outcome of empirical testing, variables on share of regular employees and the aged employees in over 50's generates a significant statistical meaning. It eventually gives a great impact on purchase of Corporate Pension scheme. Moreover, variables on corporate financial statement, current sales, current net income, total amount of the debts, labor cost per person also has a vital influence on introduction of Corporate Pension Insurance products. Lastly, variables on firm's labor relationship have no effect except for the execution or non-execution of HR consulting. Meanwhile, Variables affecting a choice on pension schemes types among firm's attributes are a share of regular employees, current net income, execution or non-execution of HR consulting etc. These variables represents a statistical implication. According to their each features, they prefer DB or DC plan. Conclusions - Introduction of corporate pension scheme is apposite to contemporary Korea's situation entering a hyper-aging society and firms with a high share of regular employees, the weight of aging, current sales, current net income and labor cost per person are exceedingly active in purchasing Corporate Pension Insurance products. However, after the introduction of corporate pension scheme, firms which has an implementation of consultation on human resource management, flexible benefits plan, job security and welfare system prefer DC plan whereas from financial perspective firms with high net income prefer DB plan.