• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권10호
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• pp.3793-3814
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• 2021

Most secure solutions like cryptography are software based and they are designed to mainly deal with the outside attacks for traditional networks, but such soft security is hard to be implemented in wireless sensor networks to counter the inside attacks from internal malicious nodes. To address this issue, reputation has been introduced to tackle the inside malicious nodes. Reputation is essentially a stimulating mechanism for nodes' cooperation and is employed to detect node misbehaviors and improve the trust-worthiness between individual nodes. Among the reputation models, binomial distribution based reputation has many advantages such as light weight and ease of implementation in resource-constraint sensor nodes, and accordingly researchers have proposed many insightful related methods. However, some of them either directly use the modelling results, apply the models through simple modifications, or only use the required components while ignoring the others as an integral part of the whole model, this topic still lacks a comprehensive and systematical review. Thus the motivation of this study is to provide a thorough survey concerning each detailed functional components of binomial distribution based reputation for wireless sensor networks. In addition, based on the survey results, we also argue some open research problems and suggest the directions that are worth future efforts. We believe that this study is helpful to better understanding the reputation modeling mechanism and its components for wireless sensor networks, and can further attract more related future studies.

• 수산경영론집
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• 제38권2호
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• pp.79-101
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• 2007

The purpose of this study is to estimate the economic value of the Songieong Beach in Off-season, using a Individual Travel Cost Model(ITCM). Songieong Beach is located in Busan but far away from city. These days, however, the increased rate of traffic inflow to the Songieong beach and the five-day working week are reflected in the trend analysis. Moreover, people have changed psychological value. For that reason, visitors are on the increase on the beach in off-season. The ITCM is applied to estimate non-market value or environmental Good like a Contingent Valuation Method and Hedonic Price Model etc. The ITCM was derived from the Count Data Model(i.e. Poisson and Negative Binomial model). So this paper compares Poisson and negative binomial count data models to measure the tourism demands. The data for the study were collected from the Songjeong Beach on visitors over the a week from November 1 through November 23, 2006. Interviewers were instructed to interview only individuals. So the sample was taken in 113. A dependent variable that is defined on the non-negative integers and subject to sampling truncation is the result of a truncated count data process. This paper analyzes the effects of determinants on visitors' demand for exhibition using a class of maximum-likelihood regression estimators for count data from truncated samples, The count data and truncated models are used primarily to explain non-negative integer and truncation properties of tourist trips as suggested by the economic valuation literature. The results suggest that the truncated negative binomial model is improved overdispersion problem and more preferred than the other models in the study. This paper is not the same as the others. One thing is that Estimating Value of the Beach in off-season. The other thing is this study emphasizes in particular 'travel cost' that is not only monetary cost but also including opportunity cost of 'travel time'. According to the truncated negative binomial model, estimates the Consumer Surplus(CS) values per trip of about 199,754 Korean won and the total economic value was estimated to be 1,288,680 Korean won.

• Communications for Statistical Applications and Methods
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• 제18권4호
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• pp.507-516
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• 2011

상관된 이항자료에 대한 일반화 이항모형들을 비교한 연구들은 고려한 모형과 비교기준에서 결과가 제한적이라는 측면이 있다. 이 연구는 모형선택의 가능한 지침을 제공하기 위해 모의실험을 통하여 모형별 적합도와 베르누이 시행의 성공확률 및 급내상관계수에 대한 ML추정량들을 비교하였다. 모수의 특정영역을 제외하고 포괄적 적합도나 추정량의 MSE 및 편의 등 성분적합에서는 대부분의 모형이 일정 수준의 경쟁적 관계에 있는 것으로 나타났다. 그러나 고려한 모형들 중 특히 일반화 확장베타이항모형 (Prentice, 1986)은 거의 모든 모수영역과 비교기준에 걸쳐 일관되게 양호한 수행력을 가지는 것으로 평가되었다.

• 방송공학회논문지
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• 제4권2호
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• pp.144-154
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• 1999

이진수열은 간단하고 곱셈기가 필요 없이 생성될 수 있는 직교 수열이다. 이 논문은 곱셈기 작동이 없는 선택적인 주파수 영상처리를 위하여 비 반복적인 다차원 필터를 도입하였다. 주파수 응답은 저역, 대역, 고역의 여파를 제공하여 준 가우시안 형태를 가진 협대역이 된다. 이런 필터들의 효과적인 구현을 위한 소프트웨어와 하드웨어의 알고리즘을 제안하였다. 또한 이진수의 QMF(Quadurature Mirror Filter: QMF)는 좋은 대역 압축을 가진 최대한의 편평한 제곱 특성의 완전 회복의 Paraunitary 필터가 됨을 보이고 웨이브렛 변환으로 확장하였다. 웨이브렛 변환은 원래의 영상을 피라미드 구조를 사용하여 다른 스케일로 분할한다. 이 분할은 수직과 수평으로 수행되어 영상을 기술하는데 필요한 픽셀의 수를 일정하게 유지시켜 준다. 효과적인 완전회복의 이진수 QMF-웨이브렛 신호의 분석구조를 제안하였다. 이 기술은 매우 좋은 주파수 응답과 대역분할을 해부는 필터 해법을 제공해준다. 이 제안한 이산 수열의 QMF-필터의 구조는 효과적이고 VLSI 구현에 간단하고 다해상도 신호 분할과 코딩의 응용들에 적합함을 보였다.

• 기술혁신학회지
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• 제17권3호
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• pp.449-466
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• 2014

그동안 기업의 R&D 투자와 기술혁신 성과의 관계에 관해 여러 연구가 있었다. 하지만 지식생산과정에 수반되는 기업의 의사결정 과정은 효과적으로 분석에 반영되지 못하였다. 특히 기업의 특허성과를 분석함에 있어 포와송모형의 한계에 대응해 최근 연구는 음이항모형을 적용해 극복하고자 했지만 기업의 선택과정을 분석하는데는 한계가 있다. 본 논문은 특허권 정보에 내재된 기업체의 의사결정 과정을 보다 효과적으로 반영하는 실증모형을 제시하고, 사업체조사 결과를 적용해 분석하였다. 특히 기업의 대표적 R&D 성과인 특허에 주목하여 특허 출원건수의 결정과정을 살펴보았다. 분석 결과, 과산포의 존재를 확인할 수 있었고, 허들모형과 일반적인 음이항모형의 결과에 유의한 차이가 있음을 제시하였다. 더불어 Wald-검정을 통해 허들의 설정이 타당하였고, 기업의 특허성과 분석에 있어서 기업의 선택과정을 고려할 필요가 있음을 보였다.

• Kyungpook Mathematical Journal
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• 제57권4호
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• pp.631-640
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• 2017

The aim of this paper is to introduce the binomial sequence spaces $b_0^{r,s}(\nabla)$, $b_c^{r,s}(\nabla)$ and $b_{\infty}^{r,s}(\nabla)$ by combining the binomial transformation and difference operator. We prove that these spaces are linearly isomorphic to the spaces $c_0$, c and ${\ell}_{\infty}$, respectively. Furthermore, we compute the Schauder bases and the ${\alpha}-$, ${\beta}-$ and ${\gamma}-duals$ of these sequence spaces.

• Journal of the Korean Data and Information Science Society
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• 제14권2호
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• pp.385-391
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• 2003

A sequence of n Bernoulli trials which violates the constant success probability assumption is termed as "Poisson trials". In this paper, the recurrence formula for the r-th central moment of number of successes with n Poisson trials is derived. Romanovsky's method, based on the differentiation of characteristic function, is used in the derivation of recurrence formula for the central moments of conventional binomial distribution. Romanovsky's method is applied to that of Poisson trials in this paper. Some central moment calculation results are given to compare the central moments of Poisson trials with those of conventional binomial distribution.

• 응용통계연구
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• 제22권1호
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• pp.129-140
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• 2009

In this paper, we consider simultaneous confidence intervals for the difference of proportions between two groups taken from multivariate binomial distributions in a nonparametric way. We briefly discuss the construction of simultaneous confidence intervals using the method of adjusting the p-values in multiple tests. The features of bootstrap simultaneous confidence intervals using non-pooled samples are presented. We also compute confidence intervals from the adjusted p-values of multiple tests in the Westfall (1985) style based on a pooled sample. The average coverage probabilities of the bootstrap simultaneous confidence intervals are compared with those of the Bonferroni simultaneous confidence intervals and the Sidak simultaneous confidence intervals. Finally, we give an example that shows how the proposed bootstrap simultaneous confidence intervals can be utilized through data analysis.

• 한국안전학회지
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• 제30권2호
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• pp.70-76
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• 2015

This study deals with the traffic accident of circular intersections. The purpose of the study is to develop the accident models by traffic violation type. In pursuing the above, this study gives particular attention to analyzing various factors that influence traffic accident and developing such the optimal models as Poisson and Negative binomial regression models. The main results are the followings. First, 4 negative binomial models which were statistically significant were developed. This was because the over-dispersion coefficients had a value greater than 1.96. Second, the common variables in these models were not adopted. The specific variables by model were analyzed to be traffic volume, conflicting ratio, number of circulatory lane, width of circulatory lane, number of traffic island by access road, number of reduction facility, feature of central island and crosswalk.

• 한국안전학회지
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• 제29권6호
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• pp.151-157
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• 2014

This study deals with the rear-end collision at roundabouts. The purpose of this study is to develop the accident models of rear-end collision in Korea. In pursuing the above, this study gives particular attention to developing the appropriate models using Poisson, negative binomial model, ZAM, multiple linear and nonlinear regression models, and statistical analysis tools. The main results are as follows. First, the Vuong statistics and overdispersion parameters indicate that ZIP is the most appropriate model among count data models. Second, RMSE, MPB, MAD and correlation coefficient tests show that the multiple nonlinear model is the most suitable to the rear-end collision data. Finally, such the independent variables as traffic volume, ratio of heavy vehicle, number of circulatory roadway lane, number of crosswalk and stop line are adopted in the optimal model.