• 대한안전경영과학회지
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• 제12권3호
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• pp.183-188
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• 2010

The recent market trend of demand and supply of domestic paper industry expected confusion in near future due to massive imports of low cost product because of suddenly emerging of China's mass productive equipment and capacity. Related domestic industry is deploying joint co-coperative partnership and logistic service, joint operations of transportation and distribution center and innovation activity for customer satisfaction. This paper tries to present a solution through analysis of related paper industry a case study.

• Journal of the Korean Data and Information Science Society
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• 제23권4호
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• pp.833-841
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• 2012

In this paper, we develop the noninformative priors for the ratio of the scale parameters in the half logistic distributions. We develop the first and second order matching priors. It turns out that the second order matching prior matches the alternative coverage probabilities, and is a highest posterior density matching prior. Also we reveal that the one-at-a-time reference prior and Jeffreys' prior are the second order matching prior. We show that the proposed reference prior matches the target coverage probabilities in a frequentist sense through simulation study, and an example based on real data is given.

• Journal of Korea Artificial Intelligence Association
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• 제1권2호
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• pp.7-13
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• 2023

In this paper, Depression is a mental disorder characterized by a lack of enthusiasm and feelings of sadness, which significantly impairs daily functioning. In 2018, there was an increase in book sales in the essay genre, particularly the popularity of "healing essays." This trend is seen as challenging the negative image and prejudices associated with depression. In 2021, a significant rise in the proportion of 20-year-old patients with depression is attributed to factors like job-related stress, interpersonal issues, and financial burdens. Additionally, there is a strong correlation between depression and suicidal thoughts, particularly among individuals who have experienced feelings of depression. Despite the increasing prevalence of depression among young adults, research in this area is lacking. To address this gap, statistical tools such as logistic regression and chi-squared tests are employed. The analysis reveals various independent variables associated with feelings of depression, shedding light on the relationships between these factors.

• 한국지리정보학회지
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• 제19권1호
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• pp.94-105
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• 2016

본 연구에서는 30년간의 전자기후자료와 현지조사자료를 활용하여 로지스틱 회귀모형을 이용한 상록활엽수림의 생육분포 확률을 평가하였다. 로지스틱 회귀모형에 의한 생육분포 확률은 33~84% 범위를 보이고 있는데 특히, 고도가 높아질수록 생육분포 확률은 낮아지는 패턴을 보이고 있다. 아울러 온 난대림육성권역에서 생육분포 확률이 63~83%로 가장 높은 것으로 추정되었다.

• 응용통계연구
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• 제30권5호
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• pp.775-791
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• 2017

이진 데이터는 일상 생활에서 자주 접할 수 있는 데이터이다. 이진 데이터를 회귀 분석하는 방법으로 로지스틱(Logistic), 프로빗(Probit), Cauchit, Complementary log-log 모형이 주로 쓰이는데, 이 방법 이외에도 Liu(2004)가 제시한 t 분포를 이용한 로빗(Robit) 모형, Kim 등 (2008)에서 제시한 일반화 t-link 모형을 이용한 방법 등이 있다. 유연한 분포를 이용하면 유연한 회귀 모형이 가능해지는 점에 착안하여, 이 논문에서는 Theodossiou(1998)에서 제시된 기운 일반화 t 분포 (Skewed Generalized t Distribution)의 이용하여 우도 함수를 최대로 하는 이진 데이터 회귀 모형을 소개한다. 기운 일반화 t 분포를 R glm 함수, R sgt 패키지를 연결하여 이 논문에서 제시한 방법을 R로 분석할 수 있는 방법을 소개하고, 피마 인디언(Pima Indian) 데이터를 분석한다.

• Journal of the Korean Data and Information Science Society
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• 제25권1호
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• pp.177-185
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• 2014

로지스틱회귀모형에서 설명변수만으로는 충분히 설명이 되지 못하고 설명변수의 변환된 형태인 이차항 또는 교호작용항이 필요한 경우가 있다. 설명변수가 두 개이고 조건부 분포가 이변량 정규분포를 따르는 경우 로지스틱회귀모형에서는 기본적으로 이차항과 교호작용항이 모형에 포함되어야 한다. 하지만 조건부 분포의 분산과 상관계수에 따라 이차항과 교호작용항이 필요하지 않게 되는 경우도 있다. 분산이나 상관계수에 대한 정보는 산점도를 보고 대체적인 판단이 가능하지만 교호작용항의 필요성을 판단하기가 쉽지 않다. 본 논문에서는 3차원 잔차산점도를 이용한 교호작용의 탐색방법을 제시하고 이 방법을 실제 자료에 적용시켜본다.

• The Journal of Asian Finance, Economics and Business
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• 제2권3호
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• pp.33-36
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• 2015

Innovations in the procurement logistics now is very popular in Kazakhstan. Nowadays there are a lot of documents of transport infrastructure and Kazakhstan logistic system is developing more and more. Procurement logistic is the direction where you can count, sometimes you can buy some products or transport equipments. Logistic in Kazakhstan is new direction, there are a lot of young people who choose this specialty and will stay demanded. Our president said a lot of words in strategies about development in logistics and so there will be new methods that will be used here. Innovations are new technologies that are used in different spheres so this structure as procurement logistic will develop in Kazakhstan and every citizen of our republic will support it. Transport systems are used for transitions different products so there are a lot new transition roads for example Western China - Western Europe; Astana-Almaty; Astana-Ust-Kamenogorsk; Astana-Aktobe, Atyrau; Almaty - Ust-Kamenogorsk; Karaganda - Zhezkazgan - Kyzylorda; Atyrau-Astrakhan, it helps Kazakhstan to support international links between other countries.

• The Journal of Asian Finance, Economics and Business
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• 제9권2호
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• pp.177-183
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• 2022

The COVID-19 pandemic has hurt the economy and negatively impacted all enterprises' financial performance. The COVID-19 pandemic has put a strain on global manufacturing capacity and supply chains, and it is also the pandemic that has given up new opportunities for the logistics industry to develop as e-commerce has developed. By analyzing the financial performance of logistic firms listed on the Vietnam Stock Exchange, this study tries to quantify those consequences. A total of 114 logistic companies were included in the study's sample. The Wilcoxon Signed Rank Test was performed to test the difference between some ratios in 2019 and 2020. This study found that the financial performance of 114 logistic firms listed on the Vietnam stock exchange has not improved. The data show that during the COVID-19 pandemic, the leverage ratio increased while the profitability and efficiency ratios decreased. The liquidity ratio did not show any significant differences. On the contrary, these businesses' performance, such as returns on assets, receivable turnover, and leverage, has decreased. The COVID-19 had a global impact on supply chains, therefore export activity and international transportation were badly hampered, with only a few domestic logistic enterprises growing.

• 한국지형학회지
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• 제27권2호
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• pp.1-17
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• 2020

This study evaluated a debris landform distribution potential area map in the southwest region of the Korean peninsula. A GIS spatial integration technique and logistic regression method were used to produce a distribution potential area map. Seven topographic and environmental factors were considered for analysis and 28 different data set were combined and used to get most effective results. Moreover, in an accuracy assessment, the extracted results of the Distribution Potential area were evaluated by conducting a cross-validation module. Block stream showed the highest accuracy in the combination No. 6, and that DEM (digital elevation model) and TWI (topographic wetness index) have relatively high influences on the production of the Block stream Distribution Potential area map. Talus showed the highest accuracy in the combination No. 13. We also found that slope, TWI and geology have relatively high influences on the production of the Talus Distribution Potential area map. In addition, fieldwork confirmed the accuracy of the input data that were used in this study, and the slope and geology were also similar. It was also determined that these input data were relatively accurate. In the case of angularity, the block stream was composed of sub-rounded and sub-angular systems and Talus showed differences according to the terrain formation. Although the results of the rebound strain measurement using a Schmidt's hammer did not shown any difference in topographic conditions, it is determined that the rebound strain results reflected the underlying geological setting.

• Food Science and Biotechnology
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• 제17권3호
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• pp.659-663
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• 2008

Different statistical distribution functions were examined to find an adequate distribution function to describe the microbial contamination behavior of a Korean side dish product, seasoned soybean sprouts for different seasons and market groups. The triang distribution was the best for any market groups in winter, while the logistic distribution could describe the microbial contamination in log CFU/g for all the market groups in spring and summer. From parametric bootstrapping based on the fitted distributions, it was found that a normal distribution could describe the distribution of mean microbial count in log CFU/g for all the seasons and market groups. Statistical parameters for each season/market group are presented to estimate the confidence interval.