• Journal of Korean Institute of Industrial Engineers
• /
• v.10 no.2
• /
• pp.29-36
• /
• 1984

This paper proposes a procedure for solving a multi-stage stockpile problem with budget constant. To establish the stockpile importance index, value assessment procedure is employed with two attributes; item's essentiality and Unsatisfactoriness rate of requirements, Then we propose the balancing of stockpile importance index among stockpile items as a reasonable objective for stockpile problem.

• Proceedings of the Korean Institute of Industrial Safety Conference
• /
• 2002.11a
• /
• pp.281-285
• /
• 2002

Although DC ground resistance is a good index of performance for a grounding system, it does not reflect the grounding performance during the transient states. Besides, impulse ground impedance, which is defined by a ratio of the peak value of transient ground potential rise to the peak value of impulse current, cannot be an absolute performance index due to its dependence on impulse current shape. In this paper, a grounding performance of needle-typed ground rod has been compared with simple ground rod using HIFREQ[1], which is an engineering electro-magnetic code based on MoM (Method of Moment).

• Bulletin of the Korean Mathematical Society
• /
• v.47 no.2
• /
• pp.411-422
• /
• 2010

By using the fixed point index theory, we investigate the existence of at least two positive solutions for p-Laplace equation with sign-changing nonlinear terms $(\varphi_p(u'))'+a(t)f(t,u(t),u'(t))=0$, subject to some boundary conditions. As an application, we also give an example to illustrate our results.

• Journal of Korea Society of Industrial Information Systems
• /
• v.5 no.3
• /
• pp.77-86
• /
• 2000

The main objectives of this dissertation is to propose a forth generation index C for the case where the target value T is not equal to the midpoint of the specification limits (i.e. asymmetric tolerances), and show that this index is more sensitive compared to the standard PCI's in detacting small shifts of the process mean from the target value. In conclusion, in this dissertation , a new methods for estimating a measure of process capability for non-normally distributed variable data is proposed using the percentage nonconforming.

• Korean Journal of Radiology
• /
• v.22 no.6
• /
• pp.922-930
• /
• 2021

Objective: It is uncertain why a b-value range of 1500-2000 s/mm² is optimal. This study was aimed at qualitatively and quantitatively analyzing the optimal b-value range of synthetic diffusion-weighted imaging (sDWI) for evaluating prostatic index lesions. Materials and Methods: This retrospective study included 92 patients who underwent DWI and targeted biopsy for magnetic resonance imaging (MRI)-suggested index lesions. We generated sDWI at a b-value range of 1000-3000 s/mm² using dedicated software and true DWI data at b-values of 0, 100, and 1000 s/mm². We hypothesized that lesion conspicuity would be best when the background (i.e., MRI-suggested benign prostatic [bP] and periprostatic [pP] regions) signal intensity (SI) is suppressed and becomes homogeneous. To prove this hypothesis, we performed both qualitative and quantitative analyses. For qualitative analysis, two independent readers analyzed the b-value showing the best visual conspicuity of an MRI-suggested index lesion. For quantitative analysis, the readers assessed the b-value showing the same bP and pP region SI. The 95% confidence interval (CI) or interquartile range of qualitatively and quantitatively selected optimal b-values was assessed, and the mean difference between qualitatively and quantitatively selected b-values was investigated. Results: The 95% CIs of optimal b-values from qualitative and quantitative analyses were 1761-1805 s/mm² and 1640-1771 s/mm² (median, 1790 s/mm² vs. 1705 s/mm²; p = 0.003) for reader 1, and 1835-1895 s/mm² and 1705-1841 s/mm² (median, 1872 s/mm² vs. 1763 s/mm²; p = 0.022) for reader 2, respectively. Interquartile ranges of qualitatively and quantitatively selected optimal b-values were 1735-1873 s/mm² and 1573-1867 s/mm² for reader 1, and 1775-1945 s/mm² and 1591-1955 s/mm² for reader 2, respectively. Bland-Altman plots consistently demonstrated a mean difference of less than 100 s/mm² between qualitatively and quantitatively selected optimal b-values. Conclusion: b-value range showing a homogeneous background signal may be optimal for evaluating prostatic index lesions on sDWI. Our qualitative and quantitative data consistently recommend b-values of 1500-2000 s/mm².

• Journal of Periodontal and Implant Science
• /
• v.28 no.4
• /
• pp.631-646
• /
• 1998

The purpose of this study was to access the clinical effects of C31G, Listerine and CPC on the earlyx periodontitis when they were used as a adjunctives to the mechanical plaque control. Each groups were composed of 12 patients and in three test groups, C31G(Exp 1 group), Listerine(Exp 2 group) and CPC mouthrinse(Exp 3 group) were used three times a day. and as a control, placebo solution was used. Plaque index, gingival index, bleeding index, pocket depth and loss of attachment were measured as clinical parameters. After scaling and oral hygiene instruction, root planing is done two weeks later. During the eight weeks of experimental period, mouth gargling is done by all groups. The changes in the clinical parameters of the all sites were monitored every two weeks. The results were as follows : 1. The plaque index showed a siginificant difference in Exp 1 group compared with test 2 group after 2 weeks use of mouth rinse(P<0.05). 2. The gingival index showed a significant difference in Exp 1 group compared with baseline value(P<0.05) but there was no significant difference between the groups after 2 weeks use of mouthrinse (P<0.05). 3. The plaque index, gingival index and bleeding index showed a significant difference in all groups compared with baseline value after 4 weeks of root planing and mouthrinse use(P<0.05). but there was no significant difference between the groups(P<0.05). 4. Periodontal pocket depth showed a significant difference in all groups compared with baseline value after 4 weeks of root planing and mouthrinse use(P<0.05). and there was significant difference between the Exp 1 group and control group(P<0.05). 5. Loss of attachment showed a significant difference in all Exp groups compared with baseline value after 4 weeks of root planing and mouthrinse use(P<0.05). and there was significant difference between the Exp 1 group and control group(P<0.05). The results suggest that C31G, Listerine and CPC were effective for early periodontitis as a adjunctive to mechanical plaqe control.

• Culinary science and hospitality research
• /
• v.8 no.3
• /
• pp.21-37
• /
• 2002

The purpose if this study is to analyze the psychological preference of Family Restaurants and their behavioral characteristic and its segmentation, positioning, new product development and marketing min. Result of analysis, index and type of MBTI psychological preference are related to Family Restaurant Choice attributes intimately. Specially, "Menu composition reflected restaurant image", and "Providing of corresponded value to price"were shows considerable difference according to psychological preference. And "Providing of the corresponded value to price"of Value, Price and Image Factor, indexes, types, including all the other aspects, shows the most considerable difference. Therefore, all market of Family Restaurant when inventing or designing a menu, they should consider restaurant′s concept and image to manage a menu, and keep in mind that all customer take "value"at up most importance.

• Korean Management Science Review
• /
• v.12 no.1
• /
• pp.61-77
• /
• 1995

The Ergonomic Workload Stress Index (EWSI) was developed to predict the existence and level of the ergonomic workload stress in the workplace. To determine the validity of model, the values of the EWSI and two other similar techniques, Job Severity Index (JSI) and Physical Work Stress Index (PWSI) were evaluated in two actual industrial environments. The results from the validation study provide further substantial evidence that two techniques, JSI and PWSI, which have similar objective considerations, are significantly associated with the value of the EWSI among the employees participating in the experimentation.

• Journal of Environmental Science International
• /
• v.10 no.2
• /
• pp.129-133
• /
• 2001

The purpose of this study is to examine the property of climatological environment using the daily mean meteorological data measured at the serveral meteorological observatory for 30years(1961~1990). It was found that the distribution of discomfort index tended to mainly depend on the geographical situation in the same season. Major portions of Korea were subjected to continental except for some seaside districts. The discomfort index have a large(small) value in summer(winter) season. And there is a short interval(1 or 2 months) between summer and winter season in Korea.

• Journal of the Korean Home Economics Association
• /
• v.18 no.1
• /
• pp.41-46
• /
• 1980

In order to verify to what extent the rancidity of the soybean oil is occurred and how the various metal ions effect on the rancidity-as a result of applying heat to the soybean oil-the followings are obtained through experiments : 1. From analyzing the refractive index of soybean oil, The results are: the specific gravity-0.925 refractive index-1.475, saponification value-190, acetyl value-5.0, iodine value-120, peroxide value-5.0. 2. The degree of expediting rancidity take the following order : $Cu^{++}$/$Fe^{++}$/$Cr^{++}$/$Zn^{++}$/$Ni^{++}$/$Al^{+++}$. 3. The degree of expediting rancidity of $Cu^{++}$and $Fe^{++}$ is showed the abrubt increase of peroxide value in accordance with the increase of densidity. The most abrubt increase of peroxide show when the duration of heating reaches to the range between 20 minutes and 30 minutes. After heating for 60 minutes no definite variation is showed. 4. The degree of rancidity in heating the soybean oil added $Cu^{++}$, Fe and BHA shows the decrease of peroxide value by 2, 3 after adding $Cu^{++}$0.5 ppm. and heating for 30 minutes. As the result of measuring the value of peroxide after adding $Cu^{++}$ by 1.0 ppm and BHA by 0.01% and heating, peroxide shows the decrease by 7.8 when adding anti-oxidant. $Fe^{++}$ as well as $Cu^{++}$ shows that BHA prevents the metal ions from the expedition of rancidity.