• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.35 no.5
• /
• pp.1165-1171
• /
• 2015

Due to the increasing trend of operation and maintenance cost (O&M cost) of infrastructure, the accurate estimation of O&M cost is crucial part to the government. Recent literatures pointed out that gradual climate changes such as average temperature changes, average precipitation changes, and etc. have significant impact on infrastructure O&M cost. This research is intended to develop a long-term O&M cost prediction model of road facilities by considering the impacts of average temperature changes. For this end, the climate change scenarios of Intergovernmental Panel on Climate Change (IPCC)'s $5^{th}$ report are adopted to structure the impact of average temperature changes by using binomial lattice model. The proposed framework is expected to regional government in supporting decisions for road O&M cost.

• The Korean Journal of Applied Statistics
• /
• v.33 no.1
• /
• pp.47-59
• /
• 2020

In this paper, we present the longitudinal Markov binary regression model with t-link function when its transition order is known or unknown. It is assumed that logit or probit models are considered in binary regression models. Here, t-link function can be used for more flexibility instead of the probit model since the t distribution approaches to normal distribution as the degree of freedom goes to infinity. A Markov regression model is considered because of the longitudinal data of each individual data set. We propose Bayesian method to determine the transition order of Markov regression model. In particular, we use the deviance information criterion (DIC) (Spiegelhalter et al., 2002) of possible models in order to determine the transition order of the Markov binary regression model if the transition order is known; however, we compute and compare their posterior probabilities if unknown. In order to overcome the complicated Bayesian computation, our proposed model is reconstructed by the ideas of Albert and Chib (1993), Kuo and Mallick (1998), and Erkanli et al. (2001). Our proposed method is applied to the simulated data and real data examined by Sommer et al. (1984). Markov chain Monte Carlo methods to determine the optimal model are used assuming that the transition order of the Markov regression model are known or unknown. Gelman and Rubin's method (1992) is also employed to check the convergence of the Metropolis Hastings algorithm.

• Journal of the Korean School Mathematics Society
• /
• v.19 no.3
• /
• pp.291-308
• /
• 2016

In this paper, we did a study on the definition and properties of binomial coefficients which can be seen with the topic for the enrichment of mathematically gifted students. Using this result, studied the problem of how to solve equations containing the binomial coefficients by using the mathematical induction, binomial theorem, the definition of the combination, and road network model situations. And such contents can be adequately dealt with the subject of mathematics enrichment gifted and talented Education because mathematically gifted students may well be the subject of inquiry. In addition, it can be used to study the subject to experience a deep sense of mathematics. As this research, it will be introduced as an example to guide students.

• The Journal of Bigdata
• /
• v.3 no.2
• /
• pp.101-112
• /
• 2018

The purpose of the study is to predict the number of police calls using neural network which is one of the machine learning and negative binomial regression, by using the data of 112 police calls received from Chungnam Provincial Police Agency from June 2016 to May 2017. The variables which may affect the police calls have been selected for developing the prediction model : time, holiday, the day before holiday, season, temperature, precipitation, wind speed, jurisdictional area, population, the number of foreigners, single house rate and other house rate. Some variables show positive correlation, and others negative one. The comparison of the methods can be summarized as follows. Neural network has correlation coefficient of 0.7702 between predicted and actual values with RMSE 2.557. Negative binomial regression on the other hand shows correlation coefficient of 0.7158 with RMSE 2.831. Neural network has low interpretability, but an excellent predictability compared with the negative binomial regression. Based on the prediction model, the police agency can do the optimal manpower allocation for given values in the selected variables.

• KSCI Review
• /
• v.8 no.2
• /
• pp.43-50
• /
• 2001

소프트웨어 신뢰성을 향상시키는 방법에는 소프트웨어 결함 허용기법 중에서 가장 객관적이고 정량적으로 평가받는 것이 NVP(N-Version Programming)기법이다. 이 기법에서 신뢰도를 추정하는 모델로 이항분포를 사용하는데 이 모델은 각 컴포넌트 신뢰도의 값들이 동일하다는 한계점이 있었다. 본 연구에서는 기존 모델의 한계점을 해결하기 위하여 NVP 신뢰도 분석을 위한 새로운 접근 방법으로 유전자 알고리즘(Genetic Algorithms)을 적용하였고. 또한 적용 모델과 기존 모델을 서로 비교 검토하였다. 그 결과 전체시스템 신뢰도를 일정 수준이상 유지하면서 각 컴포넌트 신뢰도의 값들을 최적화 할 수 있었고. 또한 비용을 최소로 하는 최적의 수를 추정할 수 있었다. 그리고 적용 모델과 기존 모델을 비교 및 평가하여 타당성을 증명하였다.

• The Journal of the Acoustical Society of Korea
• /
• v.11 no.1E
• /
• pp.5-14
• /
• 1992

본 논문은 실시간 음성 다이얼링 시스템 구현을 위한 화자종속의 단독어 인식에 대하여 기술하 였다. 인식을 위한 모델 작성은 적은 메로리에 계산 시간이 적게 걸리는 DMS 모델을 사용하였다. 인식 대상어는 대학교내의 50개 부서명을 선택하여고, 발성후 3초내에 인식결과를얻을 수 있었다. 시스템은 구간 수 22에서 가중치 0.6의 DMS 모델을 표준패턴으로 사용하였을 때 98%의 성능을 나타냈다.

• Korean journal of applied entomology
• /
• v.51 no.2
• /
• pp.91-97
• /
• 2012

The dispersion indices, spatial pattern and sampling plan for pink citrus rust mite (PCRM), Aculops pelekassi, monitoring was investigated. Dispersion indices of PCRM indicated the aggregated spatial pattern. Taylor's power law provided better description of variance-mean relationship than Iwao's patchiness regression. Fixed-precision levels (D) of a sequential sampling plan were developed using by Taylor's power law parameters generated from PCRM on fruit sample (cumulated number of PCRM in $cm^2$ of fruit). Based on Kono-Sugino's empirical binomial the mean density per $cm^2$ could be estimated from fruit ratio with more than 12 rust mites per $cm^2$: $ln(m)=4.61+1.23ln[-ln(1-p_{12})]$. To determine the optimal tally threshold, the variance (var(lnm)) for mean (lnm) in Kono-Sugino equation was estimated. The lower and narrow ranged change of variance for esimated mean showed at a tally threshold of 12. To estimate PCRM mean density per $cm^2$ at fixed precision level 0.25, the required sample number was 13 trees, 5 fruits per tree and 2 points per fruit (total 130 samples).

• Journal of Korean Society of Transportation
• /
• v.26 no.5
• /
• pp.101-115
• /
• 2008

This study reports UTIS(Urban Traffic Information System), which has been generalized in developed countries through brisk research and development and is being promoted for introduction by National Police Agency and Road Traffic Authority to reduce the astronomical amount of social expenses including traffic congestion expenses. Also this study investigates the proper charges for using by the preestimate of demand and contentment according to methods of payment after the service is introduced. The results of this study are as follows. First, demand forecast model is constructed by Binary Logit Model. Second, forecast models of using aspects of UTIS service according to methods of payment are established by Ordered Probit Model. Third, the proper charges for using of UTIS service according to methods of payment are presented to the supplier in the aspects of users. For this, preferences by using aspects and methods of payment are captured. And unit elasticity of coefficient of utilization is understood through responsiveness analysis according to methods of payment.

• Journal of Industrial Convergence
• /
• v.22 no.8
• /
• pp.1-17
• /
• 2024

Recently, interest in edutech has been focused on its fusion with AI technology, and the market in this field is expanding. This study aims to analyze the technological competitiveness and key technological areas of major countries in the AI-edutech field. Additionally, considering that AI-edutech is a convergence of AI technology and edutech, the study seeks to examine the path dependence of AI-edutech in each country to determine whether they are based on existing AI technologies or edutech. To this end, AI-edutech patents were collected and competitiveness was analyzed using patent activity, patent impact, and market acquisition indicators. Path dependence for each country was analyzed using the hurdle negative binomial regression model. The analysis results indicate that the major countries in the AI-edutech field are China, South Korea, the United States, India, and Japan. In terms of patent activity, China had the highest level, followed by South Korea. In terms of patent impact and market securing power, the United States was high in both aspects, Japan had high market securing power, and South Korea had high patent influence. The results of the hurdle negative binomial analysis presented unique findings. The logit part results indicated that the possession of existing AI and edutech did not positively affect the emergence of current AI-edutech, but the count part results showed a positive influence. This suggests that, overall, it is difficult to assert that current AI-edutechs are based on past AI and edutechs. However, once some AI-edutechs based on existing AI and edutechs emerge, they are influenced by the existing technologies. These findings provide implications for future research and technological strategies in this field.

• The Journal of the Acoustical Society of Korea
• /
• v.17 no.7
• /
• pp.22-27
• /
• 1998

본 논문에서는 ETRI에서 개발한 가변 어휘 음성 인식기의 어휘 독립 음향 모델링 방법을 기술하고, 이 모델의 어휘 종속, 어휘 독립 및 어휘적응 성능을 평가하기 위하여 다 양한 고립단어 및 연속음성 DB에 대하여 실험한 결과를 분석하였다. 평가를 위하여 사용한 음성 DB로는 고립단어 음성으로 POW(Phonetically Optimized Words) 3848, PBW(Phonetically Balanced Words) 445, PBW 452, 호텔예약 244 단어, 게임 제어용 단어 등이며, 연속음성으로 일반 문장 음성 및 연속 숫자음을 이용하였다. 성능 분석 결과 40개 음소 모델만으로도 비교적 높은 인식률을 보여 주었지만, 어휘독립의 경우는 어휘종속에 비 하여 성능이 크게 낮았고, 특히 대상 어휘가 숫자음, 알파벳, 연속음 등의 경우에는 POW 데이터나 PBW 데이터만 가지고는 우수한 가변 어휘 음성 인식기를 구현하기에 한계가 있 음을 알 수 있다. 또한, 훈련 데이터의 어휘와 평가데이터의 어휘가 비슷할 경우에는 변이음 모델을 사용하면 음소 모델만을 사용할 경우에 비하여 그 성능이 우수하였지만, 일반적인 어휘독립의 상황에서는 효과가 별로 없음을 알 수 있었다.