• 대한산업공학회지
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• 제39권2호
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• pp.109-118
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• 2013

We propose a method for estimating coefficients of AR (autoregressive) model which named MLPAR (Maximum Likelihood of Pearson system for Auto-Regressive model). In the present method for estimating coefficients of AR model, there is an assumption that residual or error term of the model follows the normal distribution. In common cases, we can observe that the error of AR model does not follow the normal distribution. So the normal assumption will cause decreasing prediction accuracy of AR model. In the paper, we propose the MLPAR which does not assume the normal distribution of error term. The MLPAR estimates coefficients of auto-regressive model and distribution moments of residual by using pearson distribution system and maximum likelihood estimation. Comparing proposed method to auto-regressive model, results are shown to verify improved performance of the MLPAR in terms of prediction accuracy.

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10525-10529
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• 2015

Objective: To investigate the relationship between the perception of cancer risk and likelihood of having undergone cancer screening. Materials and Methods: We used data from the Korean Health Panel Survey from December 2011 onward. Of 3,390 patients who visited a hospital during the previous year, we included data from 2,466 individuals; 924 samples were excluded due to missing data. Logistic regression analysis and the chi square test were used to investigate the association between perceived cancer risk and the likelihood of having undergone cancer screening. Results: For patients who perceived their risk of developing cancer during the next 10 years to be 30-40%, the odds ratio was increased 1.65 fold (95%CI: 1.223, 2.234) compared with those who perceived their risk to be almost zero. Although the difference was not statistically significant, perceiving cancer risk as either extremely low or extremely high appears to be associated with a reduced likelihood of having undergone cancer screening, resulting in an inverted U-shaped relationship. Conclusions: Physicians and researchers should be aware of the importance of the affective component of risk perception. Policies addressing the influence of cancer risk perception should be implemented in South Korea and worldwide.

• 한국정보과학회논문지:소프트웨어및응용
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• 제36권4호
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• pp.273-282
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• 2009

소프트웨어 프로젝트 데이터를 이용한 각종 분석 예측 모델 생성시 직면하는 문제 중 하나는 데이터에 포함된 결측값이며 이에 대한 효과적인 방안은 결측값 대치 법이다. 대표적인 결측값 대치법인 K 최근접 이웃 대치법은 대치과정에서 결측값을 포함하는 인스턴스의 관측정보를 활용하지 못한다는 단점이 있다. 본 연구에서는 이러한 단점을 극복하기 위해 K 최근접 이웃 대치법과 최대 우도 추정법을 결합한 새로운 소프트웨어 프로젝트 수치 데이터용 결측값 대치법을 제안한다. 또한 결측값 대치법의 정확도를 비교하기 위한 새로운 측도를 함께 제안한다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.314-317
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• 2004

The aim of this study was to evaluate the susceptibility from landslides in the Lai Chau region of Vietnam, using Geographic Information System (GIS) and remote sensing data, focusing on the relationship between tectonic fractures and landslides. Landslide locations were identified from an interpretation of aerial photographs and field surveys. Topographic and geological data and satellite images were collected, processed, and constructed into a spatial database using GIS data and image processing techniques, and a scheme of the tectonic fracturing of the crust in the Lai Chau region was established. In this scheme, Lai Chau was identified as a region with low crustal fractures, with the grade of tectonic fracture having a close relationship with landslide occurrence. The factors found to influence landslide occurrence were: topographic slope, topographic aspect, topographic curvature, distance from drainage, lithology, distance from a tectonic fracture and land cover. Landslide prone areas were analyzed and mapped using the landslide occurrence factors employing the probability-likelihood ratio method. The results of the analysis were verified using landslide location data, and these showed a satisfactory agreement between the hazard map and existing landslide location data.

• Asian Pacific Journal of Cancer Prevention
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• 제14권1호
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• pp.293-297
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• 2013

Background: : Chemotherapy-induced thrombocytopenia (CIT) is an important cause of morbitity in patients with cancer. Aim: To investigate the effect of the baseline plasma D-dimer level, an important marker for thrombotic activity, on chemotherapy-induced thrombocytopenia in patients with stage III colon cancer. Materials and Methods: A total of 43 (28 men) eligible patients were divided into two groups according to whether they exhibited chemotherapy-induced thrombocytopenia: Group 1 (n=21) and Group 2 (n=22). Comparison was made using demographic, histopathologic, and laboratory variables. Additionally, baseline plasma D-dimer levels underwent receiver operation characteristics curve analysis, and areas under the curve were calculated. Sensitivity, specificity, and positive and negative likelihood rates were then determined. Results: The incidence of chemotherapy-induced thrombocytopenia had a significant correlation with baseline platelet count (r=0.568, P=0.031) and baseline plasma D-dimer levels (r=0.617, P=0.036). When the cut-off point for the latter was set as 498 ng/mL, the area under the curve was 0.89 (95%CI: 0.74-0.93), the sensitivity was 91.4%, the specificity was 89.7%, the positive likelihood rate was 3.64 and the negative likelihood rate was 0.24 for chemotherapy-induced thrombocytopenia diagnosis. Conclusions: The baseline level of plasma D-dimer could help to differentiate high-risk patients for chemotherapy-induced thrombocytopenia.

• 한국가스학회지
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• 제10권1호
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• pp.1-6
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• 2006

압력설비를 안전하고 효율적으로 사용하기 위하여 본 연구에서는 API-581 절차에 의한 위험기반검사에서 취성파괴에 의한 사고발생 가능성을 정량적으로 해석하였다. 그 결과, 낮은 온도/낮은 인성파괴와 뜨임취성에서는 A 충격곡선이고. 낮은 온도와 열처리 전인 상태에서 기술종속계수(TMSF)가 큰 값을 나타내었고, $855^{\circ}F$ 취성에서는 위험도가 무시할 수 있었으나, 시그마상 취성에서는 낮은 온도의 고 시그마인 경우에 TMSF가 큰 값을 나타내어 사고발생 가능성이 매우 높았다.

• 유통과학연구
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• 제11권9호
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• pp.17-24
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• 2013

Purpose - The objective of the paper is to describe the relationship between consumer perceptions and attitudes of complaints against the behavior of their complaint. Research design, data, methodology - The study explore the process of complain intention which mediated by perceptual process and attitudinal behavior. Structural equation modeling used in this study is aim to describe the relationship simultaneously. The two samples failure (high vs. low level services) will be compared using analysis of variance. Results - The study found that the higher the alienation, the lower the perceived value of consumer complaint and the higher likelihood of successful perceived consumer complaint. The study also found the more positive the prior complaint experience, the more positive attitude toward complaining, the higher the perceived value of complaint and the higher the likelihood of successful perceived complaint. Furthermore, the perceived value of customer's complaint affect positive intention and perceived consumer likelihood of successful complaint increases intention complaint. Conclusions - The findings of this study show that the effect of a number of personal antecedents such as alienation; prior complaint experience and controllability will vary toward the complaint intention. Furthermore, the attitudinal and perceptual factors play a partial mediation role for that relationship.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권9호
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• pp.4264-4279
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• 2017

In this paper, maximum likelihood-based automatic lexicon generation using mixed-syllables is proposed for unlimited vocabulary voice interface for East Asian languages (e.g. Korean, Chinese and Japanese) in AI-assistant based interaction with mobile devices. The conventional lexicon has two inevitable problems: 1) a tedious repetition of out-of-lexicon unit additions to the lexicon, and 2) the propagation of errors during a morpheme analysis and space segmentation. The proposed method provides an automatic framework to solve the above problems. The proposed method produces a level of overall accuracy similar to one of previous methods in the presence of one out-of-lexicon word in a sentence, but the proposed method provides superior results with the absolute improvements of 1.62%, 5.58%, and 10.09% in terms of word accuracy when the number of out-of-lexicon words in a sentence was two, three and four, respectively.

• 한국농공학회지
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• 제39권3호
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• pp.83-95
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• 1997

This study was conducted to derive optimal design floods by Gamma distribution models of the annual maximum series at eight watersheds along Geum , Yeong San and Seom Jin river Systems, Design floods obtained by different methods for evaluation of parameters and for plotting positions in the Gamma distribution models were compared by the relative mean errors and graphical fit along with 95% confidence interval plotted on Gamma probability paper. The results were analyzed and summarized as follows. 1.Adequacy for the analysis of flood flow data used in this study was confirmed by the tests of Independence, Homogeneity and detection of Outliers. 2.Basic statistics and parameters were calculated by Gamma distribution models using Methods of Moments and Maximum Likelihood. 3.It was found that design floods derived by the method of maximum likelihood and Hazen plotting position formular of two parameter Gamma distribution are much closer to those of the observed data in comparison with those obtained by other methods for parameters and for plotting positions from the viewpoint of relative mean errors. 4.Reliability of derived design floods by both maximum likelihood and method of moments with two parameter Gamma distribution was acknowledged within 95% confidence interval.

• 한국정보처리학회논문지
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• 제1권4호
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• pp.511-516
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• 1994

본 논문에서는 전송 잡음 환경 하에서 전자파 산란 물체의 식별을 위하여 사용하 는 파라메타 측정 기법에 관한 연구이다. 최대 유사측정(Maximum Likelihood Estimation : MLE)기법은 물체 식별에 변형하여 응용되면 종래 잘 알려져 사용되어온 함수군속(Pencil of Functions) 기법보다 더 좋은 측정결과를 가진다는 것을 본 논문 은 보여주고 있다. MLE 기법을 포함하여 파라메타 식별을 위한 도구로서 지금까지 여러 제안기법들이 있었으나, 본 논문에서는 샘플 데이타의 길이에 관계없이 목표시 스템의 파라메타 양에만 관계하는 최소단위의 메트릭스 연산이 사용됨을 보여주므로 잡음이 상재하는 추출 데이타로부터 목표식별에 가장 강한 강점이 있다.