• Journal of the Korean Statistical Society
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• v.1 no.1
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• pp.11-17
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• 1973

A class of sequential binomial tests and a sequential rank test can be applied for testing two treatments when subjects are paired in many-to-one ratio. The efficiency of each test is examined in terms of the average sample number. The binomial tests are much easier and more convenient to apply than the rank test not as efficient. Within the class of binomial test, the median test appears to be the most efficient is general.

• Journal of Preventive Medicine and Public Health
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• v.40 no.1
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• pp.36-44
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• 2007

Objectives : There have been few studies examining the differences in health care utilization across social classes during the last year of life. Therefore, in this study we analyzed the quantitative and qualitative differences in health care utilization among cancer patients across educational classes in their last year of life, and derived from it implications for policy. Methods : To evaluate health care utilization by cancer patients in the last year of life, Death certificate data from 2004 were merged with National Health Insurance data (n=60,088). In order to use educational level as a social class index, we selected the individuals aged 40 and over as study subjects (n=57,484). We analyzed the differences in the medical expenditures, admission days, and rates of admission experience across educational classes descriptively. Multiple regression analysis was conducted to evaluate the association between medical expenditures and independent variables such as sex, age, education class, site of death and type of cancer. Results : The upper educational class spent much more on medical expenditures in the last one year of life, particularly during the last month of life, than the lower educational class did. The ratio of monthly medical expenditures per capita between the college class and no education class was 2.5 in the last 6-12 months of life, but the ratio was 1.6 in the last 1 month. Also, the lower the educational class, the higher the proportion of medical expenditures during the last one month of life, compared to total medical expenditures in the last one year of life. The college educational class had a much higher rate of admission experiences in tertiary hospitals within Seoul than the other education classes did. Conclusions : This study shows that the lower educational classes had qualitative and quantitative disadvantages in utilizing health care services for cancer in the last year of life.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.7 no.1
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• pp.1-6
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• 2007

The SVDD (support vector data description) is one of the most well-known one-class support vector learning methods, in which one tries the strategy of utilizing balls defined on the feature space in order to distinguish a set of normal data from all other possible abnormal objects. Recently, with the objective of generalizing the SVDD which treats all training data with equal importance, the so-called D-SVDD (density-induced support vector data description) was proposed incorporating the idea that the data in a higher density region are more significant than those in a lower density region. In this paper, we consider the problem of further improving the D-SVDD toward the use of a partial reference set for testing, and propose an LMI (linear matrix inequality)-based optimization approach to solve the improved version of the D-SVDD problems. Our approach utilizes a new class of density-induced distance measures based on the RSDE (reduced set density estimator) along with the LMI-based mathematical formulation in the form of the SDP (semi-definite programming) problems, which can be efficiently solved by interior point methods. The validity of the proposed approach is illustrated via numerical experiments using real data sets.

• Journal of Chest Surgery
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• v.31 no.11
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• pp.1031-1036
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• 1998

Background: Medtronic-Hall mechanical valve is a world widely using prosthesis. But, in Korea, the clinical result from Medtronic-Hall valve replacement is not frequenthy available. Materials and methods: From March 1986 to May 1990, 50 patients underwent valve replacement surgery with Medtronic-Hall valve at Pusan National University Hospital. Seventeen were male and thirty three were female and ra nging in age from 16 to 70 years of age(mean=35 years). Results: The causes of valvular lesion were rheumatic in 43 patients, bicuspid aortic valve in 3 patients, degenerative lesion in three patients and bacterial endocarditis in one patient. The operative procedures were mitral valve replacement(MVR) in 38, aortic valve replacement(AVR) in 5 and double valve replacement(DVR) in 7. The most commonly used valve size was 21mm in AVR, 29mm in MVR. Concomitant surgical procedures were performed in 15 patients; left atrial thrombectomy in 9, left atrial auricle obliteration in 6 and tricuspid annuloplasty in 5(Kay: 2, DeVega: 3). New York Heart Association functional class was mostly Class Ⅲ or Ⅳ(91.5%) preoperatively and ClassⅠor Ⅱ(87.2%) after operation. The findings of postoperative echocardiogram of LAD, LVESD, LVEDD were reduced compared with preoperative period and ejection fraction was increased compared with preoperative period. Postoperative complications were massive bleeding in three, low cardiac output syndrome in two, thromboembolism in one and fulminant hepatitis in one patient. There were three hospital deaths and their causes were low cardiac output syndrome in two and rupture of left ventricle in one patient. The 5 year survival rate was 93.65±0.71% and 10 year actuarial survival rate was 88.27±6.42%. Conclusions: Medtronic-Hall mechanical valve has low valve related complication rate. It's durability and hemodynamic performance is comparable to other mechanical valves.

• Korean Institute of Interior Design Journal
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• v.13 no.1
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• pp.3-10
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• 2004

The subject on presentation technique is the class which helps to develop the capability of sensual and creative acts to the students who major in interior design. It helps to understand plasticity and space through the theory of the light and the object, and to develop the capability which realizes one's idea to the actual and visual formations. It also enable the students to explain their designs to the customers by studying the technique which transfers 2D diagram to 3D presentation. Because of these objectives of the class, the departments which major in interior design in Korea consider the class on presentation technique as one of the mun subjects in basic curriculum. However, most of the textbooks related to the presentation technique published in Korea are in the lack of original characteristics for the field of domestic interior design since they refer to or employ the contents of architectural field by directly translating foreign articles. In addition, most of the classes on the presentation technique are taught not by professors but by lecturers so that the class objectives may be varied by their standards for the class. Therefore, it is not easy for each department to set up the one's own characteristics in the field of presentation technique. This study is to analyze the problems in the subjects of presentation technique by investigating the current situations for the subjects on presentation technique in domestic colleges and by surveying the personnels engaged in the field of domestic interior design. Also, the study has the objective to propose the development plan of educational program for the presentation technique in order to enable the student to effectively work in real business.

• Journal of Internet Computing and Services
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• v.22 no.1
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• pp.13-22
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• 2021

Recently network based attack technologies are rapidly advanced and intelligent, the limitations of existing signature-based intrusion detection systems are becoming clear. The reason is that signature-based detection methods lack generalization capabilities for new attacks such as APT attacks. To solve these problems, research on machine learning-based intrusion detection systems is being actively conducted. However, in the actual network environment, attack samples are collected very little compared to normal samples, resulting in class imbalance problems. When a supervised learning-based anomaly detection model is trained with such data, the result is biased to the normal sample. In this paper, we propose to overcome this imbalance problem through One-Class Anomaly Detection using an auto encoder. The experiment was conducted through the NSL-KDD data set and compares the performance with the supervised learning models for the performance evaluation of the proposed method.

• International Journal of Contents
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• v.12 no.4
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• pp.62-68
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• 2016

This paper describes an attempt to integrate flip teaching into a language classroom by adopting wikispaces as an online learning platform. The purpose of this study is to examine student perceptions of the effectiveness of using video lectures and wikispaces to foster active participation and collaborative learning. Flipped learning was implemented in an English writing class over one semester. Participants were 27 low intermediate level Korean university students. Data collection methods included background questionnaires at the beginning of the semester, learning experience questionnaires at the end of the semester, and semi-structured interviews with 6 focal participants. Because of the significance of video lectures in flip teaching, oCam was used for making weekly online lectures as a way of pre-class activities. Every week, online lectures were posted on the school LMS system (moodle). Every week, participants met in a computer room to perform in-class activities. Both in-class activities and post-class activities were managed by wikispaces. The results indicate that the flipped classroom facilitated student learning in the writing class. More than 53% of the respondents felt that it was useful to develop writing skills in a flipped classroom. Particularly, students felt that the video lectures prior to the class helped them improve their grammar skills. However, with respect to their satisfaction with collaborative works, about 44% of the participants responded positively. Similarly, 44% of the participants felt that in-class group work helped them interact with the other group members. Considering these results, this paper concludes with pedagogical suggestions and implications for further research.

• Korean Journal of Cleft Lip And Palate
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• v.6 no.2
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• pp.59-67
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• 2003

A cephalometric study was performed to reveal differences between skeletal Class III malocclusion patients and cleft lip and palate patients, The material for this study consisted of 16 males (mean age 19.8, range 17-29) and 9 females(mean age 19.4, range 16-27) with cleft lip and palate, and 222 Skeletal Class III malocclusion patients(males 106, females 116), Cephalometric tracing and measurements were done by one investigator. Results were followed: 1. Cleft lip and palate group had more retrusive maxilla than the skeletal Class III malocclusion group. 2, Cleft lip and palate group had smaller effective maxillary and mandibular length than skeletal Class III malocclusion group, and the difference was more prominent in the mandible than in the maxilla. 3. Dental compensation was not observed in the upper incisors of cleft lip and palate group and in the lower incisors it was smaller than skeletal Class III group. 4, In the Gonial angle and lower anterior facial height values, there was no significant difference between cleft lip and palate and skeletal Class III malocclusion group. These results can be used in orthodontic treatment planning and orthognathic surgery for the cleft lip and palate patients.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2008.10a
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• pp.78-81
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• 2008

The purpose of this research is to verify whether presentation order has an effect on the evaluation of products. In the empirical study, three types of humidifier and those of toaster were used. These products have 6 different sets of combination (3! = 3${\times}$2${\times}$1), and each set was evaluated by 15 subjects who were provided with two sets of images from humidifier and toaster in empirical study (N=90). Subjects completed measures assessing the five aspects: attractiveness, convenience, hygiene, efficiency and durability of the product. Each of the dependent measures was assessed on Likert-scale ranging 1 to 7. The ratings to the five aspects were added individually. Three types of humidifier and those of toaster were divided into 3 classes in terms of 'class A' which consists of the highest rated product, 'class C' which consists of the lowest rated product, and 'class B' which consists of the rest. Two main findings were discovered: First, the presentation order of both class A and class C influences the product evaluation whereas that of class B does not. As class A was presented as the last one, the subjects evaluated it the most positive. In the case of class C, on the contrary, when it is presented as the first is the best for itself; Secondly, the result shows that presented C-B-A sequence combination has a greater effect on entire evaluation than all other conditions in this study.

• Journal of Korea Game Society
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• v.15 no.3
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• pp.79-86
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• 2015

Effective feedback plays a key role in education environments to motivate the students and to maintain their flow. However, there usually lacks in providing effective feedbacks in education environments due to an excessive number of students and insufficient class times. The purpose of this paper is to analyze the educatees' response on game like feedback using App. In this paper, Class123 App developed and published by BravePops was used. During one semester, Class123 App had been used in engineering class and the educatees' responses on game like feedbacks using Class123 App are analyzed. Statistical analysis results show that the feedbacks using Class123 App made positive effects to motivate the students. Especially, the positive feedbacks were more effective than the negative feedbacks.