• Industrial Engineering and Management Systems
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• v.13 no.4
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• pp.421-431
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• 2014

The market basket data in the form of a binary user-item matrix or a binary item-user matrix can be modelled as a binary classification problem. The binary logistic regression approach tackles the binary classification problem, where principal components are predictor variables. If users or items are sparse in the training data, the binary classification problem can be considered as a cold-start problem. The binary logistic regression approach may not function appropriately if the principal components are inefficient for the cold-start problem. Assuming that the market basket data can also be considered as a special regression problem whose response is either 0 or 1, we propose three supervised learning approaches: random forest regression, random forest classification, and elastic net to tackle the cold-start problem, comparing the performance in a variety of experimental settings. The experimental results show that the proposed supervised learning approaches outperform the conventional approaches.

• Proceedings of the Korea Information Processing Society Conference
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• 2016.10a
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• pp.525-526
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• 2016

machine learning 기법 중 하나인 logistic regression을 이용하여 benign sample과 breast cancer sample을 구분할 수 있는데, 이 연구를 통해 classification의 정확도를 높이고 false positive와 false negative의 비율을 줄이려고 했다. 그래서 logistic regression의 parameter 값을 바탕으로 regression function에 영향을 많이 주는 feature 들을 선택하고, 영향력 있는 feature 들을 더한 새로운 feature를 추가했다. 그 결과 정확도와 F-score가 증가했으며, false positive, false negative의 비율이 감소했다.

• Journal of the Korea Safety Management & Science
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• v.3 no.1
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• pp.35-44
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• 2001

Today's environment of enterprise is changing. They have to face customers' demands with the right product, the right service and supply them at the right time. And aIso cut down logistics and inventory cost and bring up the Profit as much as they can. This means the change of putting enterprise first in importance to putting customer first in importance. therefore to correspond to customer's demand, shorting lead time is becoming a essential condition. The answer to this changes of environment is supply chain management In this study, we use Goldratt's drum-buffer-rope scheduling in between manufacturer and supplier. And when shortage of inventory occur, search for the supply chain's CCR. Pressing CCR for more production, and supply Inventory from logistic center to guide for inventory buffing. using logistic warehouse between manufacturer and supplier, can execute function of buffer.

• Journal of the Korean Data and Information Science Society
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• v.21 no.2
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• pp.317-325
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• 2010

In this paper, we develop four modified empirical distribution function (EDF) type tests using approximate maximum likelihood estimators for the half-logistic distribution based on multiply Type-II censored samples. We also propose modified normalize sample Lorenz curve polt and new test statistics. We compare the above test statistics in the sense of the power for various censored samples. We present an example to illustrate this method.

• International Journal of Internet, Broadcasting and Communication
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• v.11 no.2
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• pp.11-18
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• 2019

One of the key objectives of control systems is to maintain a system in a specific stable state. To achieve this goal, a variety of control techniques can be used and it is often uses a feedback control method. As known this kind of control methods requires mathematical model of the system. This article presents seesaw unstable system with two propellers which are controlled without use of a mathematical model instead. The goal was to control it using training data. For system control we use a logistic regression technique which is one of machine learning method. We tested our controller on the real model created in our laboratory and the experimental results show that instability of the seesaw system can be fixed at a given angle using the decision boundary estimated from the classification method. The results show that this control method for structural equilibrium can be used with relatively more accuracy of the decision boundary.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.4
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• pp.193-202
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• 2008

The objectives of this study are to analyze the spatial site characteristics of existing tombs and the change in the pattern of spatial distributions of tombs over time. The spatial distributions of tombs located in Honam province along the Honam expressway were investigated by interpreting digital aerial photographs taken in two different points of time; 1990 and 2000. According to the results of the study, the tombs newly observed in 2000 photos were located closer to roads and villages than those found in the photos of 1990. This is a finding indicating that the accessibility of tombs has been more important consideration in determining the location of tomb sites. Also found were the gentle slopes of southern aspects to be favored as tomb sites. Based on the data sets of tombs locations and their topographic site characteristics, the probability function of tombs appearance in the study area was derived using the logistic regression analysis technique. As a result, tomb sites were classified as 74.7% by logistic regression. All of six input factors (elevation, slope, aspect, distance from the roads, the town and the stream, respectively) affected the probability of tombs appearance significantly.

• Journal of Digital Convergence
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• v.14 no.2
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• pp.279-286
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• 2016

Recently, with the population growth of elderly people, concerns about oral health related to the quality of life of the elderly are increasing. The purpose of this study is to assess the association between the elderly women divided into dementia, suspected dementia, healthy groups and the remaining teeth of them. Total 177 elderly women of over 60 years old, visiting on senior center in some community dwelling, were assessed for oral condition and their cognitive function with MMSE score. All the collected data were analyzed by chi-square test, t-test, and multiful logistic regression using SPSS. Multiful logistic regression was used to analyze the relationship of dementia according to MMSE score and remaining teeth, and 95% confidence intervals were computed. Odds ratio(OR) of the number of remaining teeth 0-10 was 3.43 (95% confidence interval: 1.382-8.997). This study showed significant difference and the relationship between dementia according to MMSE score and the number of remaining teeth of the elderly women.

• Journal of the Korea Society of Computer and Information
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• v.13 no.7
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• pp.1-9
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• 2008

In this paper, make a study decision problem called an optimal release policies after testing a software system in development phase and transfer it to the user. When correcting or modifying the software, because of the possibility of introducing new faults when correcting or modifying the software, infinite failure non-homogeneous Poisson process models presented and propose an optimal release policies of the life distribution applied log-logistic distribution which can capture the increasing! decreasing nature of the failure occurrence rate per fault. In this paper, discuss optimal software release policies which minimize a total average software cost of development and maintenance under the constraint of satisfying a software reliability requirement. In a numerical example, after trend test applied and estimated the parameters using maximum likelihood estimation of inter-failure time data, make out estimating software optimal release time.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.16.1-16.8
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• 2020

Background: Cyst enucleation, which extracts only the tumor with the application of Carnoy's solution (CS), has been suggested as a conservative treatment with a low recurrence rate and morbidity. However, there has been a concern that CS's contact with inferior alveolar nerve (IAN) can cause neurons to degenerate and cause sensory dysfunction. The purpose of this retrospective cohort study aimed to investigate the neurosensory function after surgical treatment with or without the application of CS. Methods: While controlling the effects of sex, age, follow-up period, and invasion size of the tumor, we performed the binary logistic regression analysis to examine whether or not the sensory function of the patients who were treated with CS (n = 19) for the cyst enucleation procedure was significantly different from those who were not treated with CS (n = 58) at the end of the follow-up period. Results: The logistic regression result showed that the use of CS was not significantly related to the normalness of sensory function at the end of the follow-up period. Rather, the invasion size of the cyst was significantly associated with sensory dysfunction. Conclusions: CS may be used for patients who are diagnosed with OKC and UAM without much fear of its impact on sensory dysfunction. However, a small number of patients who were treated with CS experienced severe sensory damage and did not recover at the end of the follow-up period, suggesting the need for further analysis of these patients.

• Journal of Korean society of Dental Hygiene
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• v.21 no.6
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• pp.751-761
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• 2021

Objectives: The purpose of this study was to examine the relationship between limited oral function and cardiovascular disease in adults over 40 years of age. Methods: Data from the Seventh Korean National Health and Nutrition Examination Survey (2016-2018) was used. In this study, 8,766 adults over the age of 40 years were included as study subjects. They completed a health survey which included current prevalence of hypertension, stroke, myocardial infarction, and angina pectoris, as well as information about blood tests, physical measurements, and oral examinations. Statistical analyses were carried out using complex sample cross-tabulation analysis, general linear model, and logistic regression analysis. Results: The study showed that limited oral function was experienced by patients with stroke (61.3%), myocardial infarction (49.1%), cardiovascular disease (38.5%), hypertension (38.1%), and angina (36.4%) (p<0.05). In patients with stroke, the risk of limited oral function was 2.393 times higher than in patients without stroke. Patients with hypertension were 1.233 times more at risk of speaking difficulty than those without hypertension. Conclusions: Limited oral function is associated with cardiovascular disease. To improve oral health, it is necessary to provide integrated, health-based oral care.