• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.34
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• pp.193-204
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• 1995

Many studies show that the value of the warehouse is good. However, studies explicitly mention the tradeoff between costs of operating the warehouse and benefits from the warehouse. Also, it is important to know when the benefits overcome the costs. We study a one-warehouse/N-retailer(s,Q) distribution system with stochastic lead times in order to answer two questions: "What are the optimal policies of the system that minimizes total system costs\ulcorner" and given the optimal policies, "Is the value of the warehouse always good\ulcorner" We use an analytical model for answering the questions. We find that the optimal policies are different from those with deterministic lead times. In fact it is reverse. We alse find the existence of the breakeven point beyond which the benefits starts overcomming the costs. And, we show that one of the breakeven points is the mean ratio of a supplier's lead time to transportation lead time between the warehouse and the retailer. Finally, we show that the breakeven point is sensitive to the ratio of holding costs of the warehouse and the retailer and it is also sensitive to the unit backorder costs at the retailer.sts at the retailer.

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.2759-2769
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• 2018

The behavioral finance view on the existence of asset pricing anomalies is based on two factors: investors' sentiment and limits to arbitrage. This paper tries to examine the effect of investors' sentiment on the stock price in the Korean stock market. In order to measure investors' sentiment, we constructed the sentiment index using principal component of five sentiment variables. By using sentiment index as an additional independent variable to three risk factors, impacts of the sentiment index on individual stocks and 25 portfolios sorted by BM-size are examined. Main results found are as follows: 1) not only all three risk factors show positive impacts on the return of individual stock, but also the sentiment index has a positive impact. SI alone explains 15% of individual return variation. 2) among four independent variables, the most important factor turned out to be the market risk factor and investors' sentiment has better explanatory power on stock price than the size effect. 3) after controlling the market risk factor, the coefficient of the sentiment index for the smallest size and highest book/market value portfolios is significantly positive. 4) all the coefficients of the sentiment index for 25 portfolios sorted by BM-size have significant positive value after controlling size or (and) value.

• Bulletin of the Korean Chemical Society
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• v.17 no.4
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• pp.321-324
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• 1996

Sr1+xSm1-xFeO4-y solid solutions with a composition range 0.00 ≤x≤1.00 have been prepared at 1200 ℃ in air under normal atmospheric pressure. All the solutions exhibit the K2NiF4-type structure of tetragonal system. Mohr salt analysis shows that the mole ratio of Fe4+ ion to Fe3+ ion or the τ value increases with the x value. Nonstoichiometric chemical formulas have been formulated from the x, τ, and y values. Electrical conductivity was measured in the temperature range of 173-373 K under atmospheric air pressure. The conductivities of each sample are varied within the semiconductivity range. The conductivity at constant temperature increases steadily with x value and activation energies are varied from 0.14 to 0.32 eV. The conduction mechanism of the ferrite system may be proposed as a hopping model of conduction electrons between the mixed valence states. The Mossbauer spectrum for the composition of x=0.00 shows a six line pattern by which the existence of Fe3+(I.S.=0.32 mm/sec) can only be identified. The spectra for the compositions of x=0.50 and 1.00 presents broad single line patterns showing a mixed valence state.

• Journal of the Korea Concrete Institute
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• v.23 no.6
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• pp.701-709
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• 2011

One of the typical evaluation models of concrete air-void system is spacing factor (SF), which was suggested by Power. Power Spacing Factor (PSF) has a disadvantage of the result being different from the actual case due to the existence of entrapped air, because PSF uses average single spacing factor. Therefore, the Actual Measurement Spacing Factor (AMSF) using actually measured data of air void spacing was developed from this study. PSF and AMSF were compared and evaluated in this study by using the image analysis test result of concrete mixture. This study results showed that PSF and AMSF are generally similar, but AMSF had a larger value when PSF was greater than $400{\mu}m$. The results indicated a possibility of PSF giving false measurement estimation where the measurement is less than the actual value in the concrete mixture containing less air. Also, in the result of PSF and AMSF analysis according to the existence of entrapped air, AMSF showed a larger value in the analysis without entrapped air. But PSF showed a smaller value in the analysis without entrapped air, which was different from the actual case. Because PSF used average single spacing factor, it tended to give a false result. The study results showed that AMSF gave more accurate analysis results.

• Korean Journal of Community Nutrition
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• v.3 no.2
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• pp.292-307
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• 1998

This study was conducted to evaluate the eating behavior and to analyze the various factors affecting eating behavior among middle school students. The subjents consisted of 212 middle school students(106 boys and 106 girls between 13-14 years) residing in Seoul. A questionnaire was used as the questionnaire consisted of four parts : the socio-demographic characteristics of the subjects, value toward food and nutrition, diet diversity(the number of food items) and eating behavior. Results showed that fifty three point five percent of males and fifty seven percent of females skipped breakfast. The main reason for skipping breakfast was shortage of time. Fifty five percent of the total number of subjects stated that they had more than two plasant meals a day. The number of food items eaten was significantly higher in males than in females. In only 16.4% of total subjects(18.5% of male and 14.2% of female), the primary pursuit in having meals was not to satisfy hunger but to consider nutrition and health. The eating behavior of the adolescents showed that 65% of the subjects had a 'good' eating behavior score and 17.4% had scores of 'excellent' and 'poor' respectively. The existence of parents, the economic level of the family, and concern of health and nutrition affected the eating behavior score. The less the subject skipped breakfast, the greater they placed a value toward food and nutrition. Value toward food and nutrition had a significant influence on their eating behavior. Those who placed a value toward food and nutrition had a higher eating behavior. Those who placed a value toward food and nutrition had a higher eating eating behavior. As a result of the multiple regression analysis, factors affecting eating behavior were 'pleasant meal' , 'the value toward food and nutrition' and 'the numbers of food items' in order(R2=0.2984).

• Journal of Korean Academy of Nursing
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• v.15 no.3
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• pp.5-20
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• 1985

The purpose of this study was to assess the value-of post-operative treatment in terms of nursing care in the allevation of pain. More specifically, the effects of supportive touch and patient education were examined. On the date before each patient's operation, the Bevels of anxiety, depression and affiliation were examined. The post-operative treatment was adminis. tered after an initial measurement of the patient's fain, according to the experimental category for the three days following the operation. On the final day, the level of anxiety and depression were again measured. The subjects of this study were 138 patient from the general surgical and gynecological wards in H university Hospital in Seoul. The study was conducted over a three-month period from June 24, 1984 to September 18, 1984. All patients had undergone laparatomies. Various standard instruments were used to measure the pain, anxiety, depression and affiliation levels. for pain, 5 grate Simple Descriptive Scale, and the Mclachlan four-range Observational Pain Scale were employed. For anxiety and depression, respectively the Spielberger State Anxiety Inventory and Beck Depression Inventory (B.D.I.) were used. Lastly, the affiliation was determined by the Mehrabian Affiliation Scale. The outcome of the research was as follows: 1. The first hypothesis concerning the existence of lower pain levels of Experimental Group A and Experimental Group B than the pain levels of Control Croup C was not supported. 2. The second hypothesis concerning the existence if lower anxiety levels of Experimental Group A and Experimental Group B than the anxiety levels of Control Group C was supported at the level of F=3.58 (p=.03). 3. The third hypothesis concerning the existence of lower depression levels of Experimental Group A and Experimental Group B than the depression levels of Control Group C was not supported. 4. The fourth hypothesis concerning the existence of different levels of pain in accordance with the levels of affiliation in Experimental Group A was not supported. 5. A positive correlation did exist between pain and anxiety after surgery (r=.34, p=.0001). Thus, the fifth hypothesis was supported. 6. A positive correlation did exist between pain and depression following surgery(r=.36, p=.0001). Thus, the sixth hypothesis was supported. Based on the above results, it was found that supportive touch and patient education either through human sources or via tape recorder do influence the anxiety of a patient after surgery, that a Positive correlation between pain, anxiety and deparession exist, that affiliation does not alter the influence of supportive touch, and that the graph on which pain levels were depicted indicates the possibility of development even if the effects of supportive touch did not reach a meaningful level. Thus it can be concluded that patient education, regardless of its form, is essential for the patient after surgery and that supportive touch, when reasonably modified and supplemented, can be an effective method of alleviating pain.

• The Korean Journal of Applied Statistics
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• v.31 no.4
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• pp.447-461
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• 2018

Domestic film industry sales are increasing every year. Theaters are the primary sales channels for movies and the number of audiences using the theater affects additional selling rights. Therefore, the number of audiences using the theater is an important factor directly linked to movie industry sales. In this paper we consider a hybrid model that combines a multiple linear regression model and the Bass model to predict the audience numbers for a specific day. By combining the two models, the predictive value of the regression analysis was corrected to that of the Bass model. In the analysis, three films with different release dates were used. All subset regression method is used to generate all possible combinations and 5-fold cross validation to estimate the model 5 times. In this case, the predicted value is obtained from the model with the smallest root mean square error and then combined with the predicted value of the Bass model to obtain the final predicted value. With the existence of past data, it was confirmed that the weight of the Bass model increases and the compensation is added to the predicted value.

• Economic and Environmental Geology
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• v.36 no.2
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• pp.141-148
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• 2003

We investigated the distribution of sea ice using various microwave remote sensing techniques including radar altimeter, radiometer, and scatterometer data in the part of Drake passage, Antarctica, between the area 45$^{\circ}$-75$^{\circ}$W and 55$^{\circ}$-66$^{\circ}$S. Topex/poseidon radar altimeter data were used to analyze the monthly distribution of sea ice surface area between 1992 and 1999 by using Geo_bad_1 flag or MGDR. From satellite radiometer measurements of DMSP's SSM/I, sea ice concentration was extracted during the period from 1993 to 1996. To select a value of ice concentration, normally ranging from 0 to 100%, that can be used as a critical value of judging the existence for ice, sea ice areas estimated from various ice concentrations of radiometer measurements were correlated with the area estimated from the radar altimeter measurements. As a result, 20% of ice concentration was selected, and, then this value was used to integrate radiometer data with radar altimeter and ERS-1/2 scatterometer data. To indirectly verify the result, the last 20 year's sea ice concentration was correlated with surface temperature data near Esper-anza Observation Station. The two data showed a high correlation coefficient of 0.86. The amount of sea ice and temperature variation were found to be closely related in the study area, and this indirectly verifies the result of this study. We provided a method to judge the existence of sea ice from ice concentration of satellite radiometer data and suggested a method to monitor more detailed temporal and spatial variation of sea ice distribution by integra-tion of various microwave remote sensing techniques.

• Journal of Trauma and Injury
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• v.23 no.2
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• pp.83-88
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• 2010

Purpose: It is not always easy to determine the existence of tendon injuries when it comes to patients with finger lacerations. Thus, we tried to find the difference in effectiveness and in compliance of patients when we employed two different types of diagnosis, conventional gross confirmation and ultrasonographic confirmation. Methods: From December 2009 to March 2010, we enrolled 14 patients with finger tendon injury at Soonchunhyang University Cheonan Hospital. The median age of the patients was $35.9{\pm}14.4$, and the ratio of females to males was 1:2.5 We evaluated the compliance of each patient by measuring four different categories (level of cooperativeness in showing their wound and in following the instructions, level of movement of their fingers during the diagnosis and total number of attempts to diagnose) by using a score from 1 to 3 for each category, for a total possible score of 12 for each patient. We also measured the painfulness of each patient by using a score of 1 to 10 and the time required for each diagnosis. Results: The levels of patients' compliance was $8.9{\pm}2.1$ when diagnosed with gross confirmation and $9.8{\pm}2.1$ when diagnosed with ultrasonographic confirmation (p value=0.042). The pain score of the patients was $3.7{\pm}1.7$ with gross confirmation and $2.9{\pm}1.2$ with ultrasonographic confirmation (p value=0.020). The median duration of time in each test was $6.7{\pm}4.8$ minutes with gross confirmation and $10.5{\pm}4.2$ minutes with ultrasonography (p value=0.006). Conclusion: Comparing gross confirmation and ultrasonographic confirmation, gross confirmation is a better method than ultrasonography because of time efficiency. However, ultrasonographic confirmation has advantages over gross confirmation in pain scale and better compliance of patients. Emergency physicians generally employ gross confirmation rather than ultrasonography in determining the existence of tendon injury in patients. In patients with finger lacerations without bone injury, ultrasonography can be considered as a secondary diagnostic tool, especially when patients have much pain.

• Journal of Oral Medicine and Pain
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• v.32 no.2
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• pp.151-156
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• 2007

Antimicrobial action of phytoncide in the mouth decrease odor-producing microorganisms. Also phytoncide has malodor effect by reaction with volatile sulfur compounds. Phytoncide has excellent malodor effect in microbiologically and chemically. This study prove the malodor effect of phytoncide by use ferrous sulfate. So I try to make new treatment method for halitosis. I get the results as follows. 1. The difference of mean value of absorbancy was 0.849 between the mean absorbancy of deposition by add phytoncide to saliva and the saliva only. 2. The difference of mean value of absorbancy was 0.701 between the mean absorbancy of deposition by add phytoncide to distilled water and the distilled water only. 3. The difference of mean value(0.849) in saliva by existence of phytoncide was larger than in double distilled water(0.701) by existence of phytoncide. Therefore, phytoncide make more deposition in saliva than double distilled water by reaction with sulfur compounds. As the results, phytoncide reaction with sulfur compounds in saliva. It take malodor action in liquid state effectively. It is thought, only the toothpaste it knows from in the limit which does not have a side effect by the human body it adds in the oral cavity of the mouth rinse and with the fact that it will be able to use positively in clinic.