• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.7
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• pp.1-7
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• 2009

The research aims at providing data needed for planning the lighting of a study room by comparing the lighting environments of study rooms for urban and rural juveniles. The subject of the research was 300 students in middle schools in Daegu and Checngdo-gun, Gyeongsangbuk-do (Daegu 150 houses and Cheongdo 150 houses), and their study rooms were examined. The following is the result of the research. First, rural students stayed more time in their study room than urban students. The task that rural students (studying) and urban students (studying and using computer) all did in their study room was mainly visual work Second, although the sizes of rural study rooms were bigger than those of urban study rooms, urban study rooms had more light sources than rural study rooms. In the rate that of having a task lighting, the city(87.1[%]) was higher than the country (45.7[%]). However, the rate of using a task lighting was lot high in both the city and the country. Third, the result that compared the average values of illuminations on desk planes was that the average value of the city was 3.4 times higher than that of the country. Also, the average value of the country did not meet the standard illumination of Korean industrial standards (KS). In particular, it did not reach the lowest standard. The result is related with that only 52[%] of students who had a task lighting used it. Finally, the satisfaction of lighting environment in the city was generally higher than the country. Especially, although the country had a low illumination, the user showed a high satisfaction. It indicates that people living in the country need to understand about the needs of illumination.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5311-5316
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• 2013

A functional polymorphism in the NQO1 gene, featuring a 609C>T substitution,leading to proline to serine amino-acid and enzyme activity changes, has been implicated in cancer risk. However, individually published investigations showed inconclusive results, especially for leukemia. In this study, we therefore performed a meta-analysis of 21 publications with a total of 3,634 cases and 4,827controls, mainly for leukemia. We summarized the data on the association between the NQO1 609C>T polymorphism and risk of leukemia and performed subgroup analyses by ethnicity and leukemia type. We found that the variant TT homozygous genotype o was associated with a modestly increased risk of leukemia (TT versus CT/CC: OR=1.23, 95%CI=1.00-1.51, heterogeneity=0.76; $I^2$=0%). Following further stratified analyses, increased risk was only observed in subgroups of Caucasians. This meta-analysis suggests that the NQO1 609T allele is a high-penetrance risk factor for leukemia in Caucasians. The effect on leukemia may be modified by ethnicity and leukemia type, and the small sample sizes of the subgroup analyses suggest that further larger studies are needed.

• Journal of Korean Neurosurgical Society
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• v.46 no.4
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• pp.378-384
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• 2009

Objective : In order to establish the role of Gamma Knife radiosurgery (GKS) in large intracranial arteriovenous malformations (AVMs), we analyzed clinical characteristics, radiological features, and radiosurgical outcomes. Methods : Between March 1992 and March 2005, 28 of 33 patients with large AVMs (> $10\;cm^3$ in nidus-volume) who were treated with GKS underwent single session radiosurgery (RS), and the other 5 patients underwent staged volumetric RS. Retrospectively collected data were available in 23 cases. We analyzed treatment outcomes in each subdivided groups and according to the AVM sizes. We compared the estimated volume, defined as primarily estimated nidus volume using MR images, with real target volume after excluding draining veins and feeding arteries embedded into the nidus. Results : Regarding those patients who underwent single session RS, 44.4% (8/18) had complete obliteration; regarding staged volumetric RS, the obliteration rate was 40% (2/5). The complete obliteration rate was 60% (6/10) in the smaller nidus group ($10-15\;cm^3$ size), and 25% (2/8) in the larger nidus group (over $15\;cm^3$ size). One case of cerebral edema and two cases (8.7%) of hemorrhage were seen during the latent period. The mean real target volume for 18 single sessions of RS was $17.1\;cm^3$ ($10.1-38.4\;cm^3$), in contrast with the mean estimated volume of $20.9\;cm^3$ ($12.0-45.0\;cm^3$). Conclusion : The radiosurgical treatment outcomes of large AVMs are generally poor. However, we presume that the recent development in planning software and imaging devices aid more accurate measurement of the nidus volume, therefore improving the treatment outcome.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.5
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• pp.819-830
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• 2010

This study proposes medical gowns for interns and residents that address the functions of utility and activity. Based on the questionnaires, the prototype focused on the pockets for practical use and movement adaptability. Functional pockets were made by increasing pocket sizes and separating pockets with sections according to use. An inside pocket and a loop for an identification tag was placed on the chest pocket and the side seam pocket were oblique lined. To resolve horizontal stress on the back of the gown,6 cm action pleats were added at both ends of the bladebone. The elbow area was tucked up to improve the workplace activities. To reduce hamper on the gown hemline, slits were added along the gown side seam. The front button was changed into an inside button closure. The cuffs, belt, and back waist belt were removed due to occupational cases of inconvenience. The length of the sleeves was adjusted with belts to improve the movement of the arms. In accordance with design preference, the gown was designed to be knee-length with wrist length sleeves. Blue colored (2.5PB 3/12: by Munsell) material was inserted to reduce the contamination on the neck, cuffs, front closure, and hemline area. The planning cloth of the experimental gown was designed to improve activity function, cleaning, and comfort from light materials. The field test (with 30 doctors at university hospitals and the objective assessment with 9 subject groups)were done by the valuation between the existing gown and the prototype. The results showed that the prototype had to be modified by decreasing the pocket size, expanding the usage of the penholder, and simplify front pockets in order to maintain unity. The loop for the identification tag, inside pocket, and the blue colored material had to be removed. The front closure of the gown had to return to its original state.

• Journal of Animal Science and Technology
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• v.55 no.2
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• pp.103-107
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• 2013

A crucial first step in the planning of any scientific experiment is to evaluate an appropriate sample size to permit sufficient statistical power to detect the desired effect. In this study, we investigated the optimal sample size of quantitative trait locus (QTL) linkage analysis for simple random sibship samples in pedigreed chicken populations, under the variance component framework implemented in the genetic power calculator program. Using the program, we could compute the statistical power required to achieve given sample sizes in variance component linkage analysis in random sibship data. For simplicity, an additive model was taken into account. Power calculations were performed to relate sample size to heritability attributable to a QTL. Under the various assumptions, comparative power curves indicated that the power to detect QTL with the variance component method is highly affected by a function of the effect size of QTL. Hence, more power can be achievable for QTL with a larger effect. In addition, a marked improvement in power could be obtained by increasing the sibship size. Thus, the use of chickens is advantageous regarding the sampling unit issue, since desirable sibship size can be easily obtained compared with other domestic species.

• Korean Journal of Veterinary Research
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• v.50 no.1
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• pp.43-48
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• 2010

Animal disease surveillance system, defined as the continuous investigation of a given population to detect the occurrence of disease or infection for control purposes, has been key roles to assess the health status of an animal population and, more recently, in international trade of animal and animal products with regard to risk assessment. Especially, for a system aiming to determine whether or not a disease is present in a population sensitivity of the system should be maintained high enough not to miss an infected animal. Therefore, when planning the implementation of surveillance system a number of factors that affecting surveillance sensitivity should be taken into account. Of these parameters sample size is of important, and different approaches are used to calculate sample size, usually depending on the objective of surveillance systems. The purpose of this study was to evaluate the sensitivity of the current national serological surveillance programs for four selected bovine diseases assuming a specified sampling plan, to examine factors affecting the probability of detection, and to provide sample sizes required for achieving surveillance goal of detecting at least an infection in a given population. Our results showed that, for example, detecting low level of prevalence (0.2% for bovine tuberculosis) requires selection of all animals per typical Korean cattle farm (n = 17), and thus risk-based target surveillance for high risk groups can be an alternative strategy to increase sensitivity while not increasing overall sampling efforts. The minimum sample size required for detecting at least one positive animal was sharply increased as the disease prevalence is low. More importantly, high reliability of prevalence estimation was expected with increased sampling fraction even when zero-infected animal was identified. The effect of sample size is also discussed in terms of the maximum prevalence when zero-infected animals were identified and on the probability of failure to detect an infection. We suggest that for many serological surveillance systems, diagnostic performance of the testing method, sample size, prevalence, population size, and statistical confidence need to be considered to correctly interpret results of the system.

• Journal of Korean Society of Transportation
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• v.35 no.5
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• pp.385-395
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• 2017

This study deals with the small-scale roundabout. The purpose of this study is to analyze the average delay of vehicle in roundabout, and suggest the efficient planning and design standard. In pursuing the above, this study gives particular attentions to analyzing the average delay time according to the inscribed circle diameter, speed of circulatory roadway lane and traffic volume. The operational efficiencies of 96 scenarios (3 sizes of inscribed circle diameter ${\times}$ 4 types of circulatory roadway speed ${\times}$ traffic volume) are analyzed using VISSIM (Verkehr In $St{\ddot{a}}dten$-SIMulationsmodell). The main results are as follows. First, the optimal design speed of small-scale roundabout are derived from the above scenario analysis. Second, the traffic volume of LOS D is estimated to be 2,180-2,740pcph. Third, the traffic volume of LOS F that is required to improve is above 2.780pcph. The results might be expected to give some implications to providing the countermeasures for the operational efficiency of roundabout.

• Restorative Dentistry and Endodontics
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• v.39 no.3
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• pp.164-171
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• 2014

Objectives: Designing in situ models for caries research is a demanding procedure, as both clinical and laboratory parameters need to be incorporated in a single study. This study aimed to construct an informative guideline for planning in situ models relevant to preexisting caries studies. Materials and Methods: An electronic literature search of the PubMed database was performed. A total 191 of full articles written in English were included and data were extracted from materials and methods. Multiple variables were analyzed in relation to the publication types, participant characteristics, specimen and appliance factors, and other conditions. Frequencies and percentages were displayed to summarize the data and the Pearson's chi-square test was used to assess a statistical significance (p < 0.05). Results: There were many parameters commonly included in the majority of in situ models such as inclusion criteria, sample sizes, sample allocation methods, tooth types, intraoral appliance types, sterilization methods, study periods, outcome measures, experimental interventions, etc. Interrelationships existed between the main research topics and some parameters (outcome measures and sample allocation methods) among the evaluated articles. Conclusions: It will be possible to establish standardized in situ protocols according to the research topics. Furthermore, data collaboration from comparable studies would be enhanced by homogeneous study designs.

• Korean Journal of Community Nutrition
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• v.13 no.6
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• pp.879-889
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• 2008

The purpose of this study was to examine nutrition management conditions of lunch with the elementary schools and middle schools in the Changwon area. 292 students (5th and 6th graders) from three elementary schools and 330 students from three middle schools (boys, girls, and co-ed) participated in the aggregate selective plate waste measurement for 5 days. Planned menus, serving sizes and plate waste amount data were collected. Nutrient analyses for the planned, served and consumed menus at school lunches were performed by using CAN-PRO 3.0. Nutrient analyses of the planned, served and consumed menus were compared with nutrient management standard (former edition) for school lunch and 1/3 Korean Dietary Reference Intakes (KDRIs). Significant difference was found in the average consumption rate between the elementary schools (82.2%) and the middle schools (71.8%). Specifically, the consumption rates of steamed rice (p < 0.001), side dish 1 (p < 0.001), and Kimchi (p < 0.01) at the middle schools were significantly lower than those of the elementary schools. When the nutrient contents in the served menus were put into percentages to the nutrient contents in the planned menus, middle schools (92.3%) showed bigger serving loss than the elementary schools (95.4%). In the nutrient assessment comparied with nutrient management standard (former edition), middle school lunches showed comparatively less energy or less some nutrient contents against the standard than the elementary school lunches. Specifically, in case of boys in middle schools, Vitamin C was the only nutrient content that satisfied the standard in the planned menus, served menus and consumed menus. In the 1/3 KDRIs based assessment, middle schoolers were found not to be provided proper nutrients with school lunches. To improve nutrition management at middle school foodservices, dietitians should reinforce nutrient assessment for menu planning, and try to decrease serving loss and plate waste.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.3
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• pp.77-86
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• 2012

We consider the capacitated lot-sizing and scheduling problem for a paper remanufacturing system that produces several types of corrugated cardboards. The problem is to determine the lot sizes as well as the sequence of lots for the objective of minimizing the sum of setup and inventory holding costs while satisfying the demand and the machine capacity over a given planning horizon. In particular, the paper remanufacturing system has sequence-dependent setup costs that depend on the type of product just completed and on the product to be processed. Also, the setup state at one period can be carried over to the next period. An integer programming model is presented to describe the problem. Due to the complexity of the problem, we modify the existing two-stage heuristics in which an initial solution is obtained and then it is improved using a multi-pass interchange method. To show the performances of the heuristics, computational experiments were done using the real data, and a significant amount of improvement is reported.