• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.3
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• pp.753-762
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• 1996

In this paper, aperture coupled stacked microstrip array antennas are proposed and their operating characteristics are analyzed based on analytical. In order to evaluate mutual coupling between slot-coupled microstrip patches in finite array, analysis uses the reciprocity theorem and the spectral domain Green's functions for dielectric slab in a moment method solution for the unknown patches and solts current distrbution. By introducing an N-port equivalent network, the impedance matrix of an affay of N-element slot-coupled patches is evaluated directly from its network current matix of order N$^{2}$, and it can be programmed to be run on a PC. Numerical results show mutual coupling, radiation pattern, active reflection coefficient versus scan angle, radiation efficiency and active element gain pattern.

• The Korean Journal of Applied Statistics
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• v.35 no.3
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• pp.421-434
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• 2022

Chatterjee (2021) proposed a new correlation coefficient ξ. Focusing on two questions (1. Is ξ coefficient distinguishable for Anscombe's quartet data set?, 2. How does the ξ coefficient value change according to the number of data for various kinds of scatterplots?), an exploratory data analysis is attempted for ξ coefficient. We can compare three measures (ξ coefficient, Pearson's correlation coefficient and mutual information).

• International Journal of Computer Science & Network Security
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• v.24 no.6
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• pp.1-7
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• 2024

Comparing text features involves evaluating the "similarity" between texts. It is crucial to use appropriate similarity measures when comparing similarities. This study utilized various techniques to assess the similarities between newspaper articles, including deep learning and a previously proposed method: a combination of Pointwise Mutual Information (PMI) and Word Pair Matching (WPM), denoted as PMI+WPM. For performance comparison, law data from medical research in Japan were utilized as validation data in evaluating the PMI+WPM method. The distribution of similarities in text data varies depending on the evaluation technique and genre, as revealed by the comparative analysis. For newspaper data, non-deep learning methods demonstrated better similarity evaluation accuracy than deep learning methods. Additionally, evaluating similarities in law data is more challenging than in newspaper articles. Despite deep learning being the prevalent method for evaluating textual similarities, this study demonstrates that non-deep learning methods can be effective regarding Japanese-based texts.

• IEIE Transactions on Smart Processing and Computing
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• v.4 no.5
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• pp.311-317
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• 2015

The aim of this study is to develop a 3D registration algorithm for positron emission tomography/computed tomography (PET/CT) and magnetic resonance (MR) images acquired from independent PET/CT and MR imaging systems. Combined PET/CT images provide anatomic and functional information, and MR images have high resolution for soft tissue. With the registration technique, the strengths of each modality image can be combined to achieve higher performance in diagnosis and radiotherapy planning. The proposed method consists of two stages: normalized mutual information (NMI)-based global matching and independent component analysis (ICA)-based refinement. In global matching, the field of view of the CT and MR images are adjusted to the same size in the preprocessing step. Then, the target image is geometrically transformed, and the similarities between the two images are measured with NMI. The optimization step updates the transformation parameters to efficiently find the best matched parameter set. In the refinement stage, ICA planes from the windowed image slices are extracted and the similarity between the images is measured to determine the transformation parameters of the control points. B-spline. based freeform deformation is performed for the geometric transformation. The results show good agreement between PET/CT and MR images.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.9
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• pp.2056-2063
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• 2015

Recently, as the service scale of cloud service is expanded, an anxiety due to concerns on new vulnerabilities and security related incidents and accidents are also increasing. This paper proposes a certification scheme for multiple session management of security sessions which are generated after the user authentication. The proposed session multiplexing scheme enables the independent management of security sessions in the level of virtualization (hypervisor) within the service provider. As a result of performance analysis, providing a strong safety due to session multiplexing and mutual authentication, and the superiority of performance was proven by comparing it with the existing mutual authentication encryption algorithms.

• Journal of the Korean Statistical Society
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• v.26 no.1
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• pp.131-146
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• 1997

In this paper the problem of measuring the stochastic dependence among sets fo random variates is considered, and attention is specifically directed to forming a single well-defined measure of the dependence among sets of normal variates. A new information theoretic measure of the dependence called dependence index (DI) is introduced and its several properties are studied. The development of DI is based on the generalization and normalization of the mutual information introduced by Kullback(1968). For data analysis, minimum cross entropy estimator of DI is suggested, and its asymptotic distribution is obtained for testing the existence of the dependence. Monte Carlo simulations demonstrate the performance of the estimator, and show that is is useful not only for evaluation of the dependence, but also for independent model testing.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.11a
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• pp.1392-1394
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• 2010

단일염기다형성 유전형 자료에 대한 유전자형을 얻어내는 기술(genotyping)이 발달함에 따라 분석해야 하는 SNP의 개수가 수십만 개로 증가하였다. 따라서 기존의 연관성 분석(association study)연구 방법을 그대로 적용시키기는 어렵다. 본 논문에서는 상호정보량(mutual information)과 Multifactor dimensionality reduction을 이용하여 대용량의 SNP 유전형자료를 분석하는 방법을 제안하였고, 이 방법을 toluene diisocyanate-induced asthma에 대해 실험해본 결과 높은 판별력을 보이는 모델을 찾을 수 있었다.

• Journal of information and communication convergence engineering
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• v.8 no.4
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• pp.437-442
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• 2010

Ubiquitous mobile computing is becoming easier and more attractive in this ambient technological Internet world. However, some portable devices such as Personal Digital Assistant (PDAs) and smart phones are still encountering inherent constraints of limited storages and computing resources. To alleviate this problem, we develop a cost-effective protocol, iATA to transfer ATA commands and data over TCP/IP network between mobile appliances and stationary servers. It provides mobile users a virtual storage platform which is physically resided at remote home or office. As communications are made through insecure Internet connections, security risks of adopting this service become a concern. There are many reported cases in the history where attackers masquerade as legitimate users, illegally access to network-based applications or systems by breaking through the poor authentication gates. In this paper, we propose a mutual authentication and secure session termination scheme as the first and last defense steps to combat identity thief and fraud threat in particular for iATA services. Random validation factors, large prime numbers, current timestamps, one-way hash functions and one-time session key are deployed accordingly in the scheme. Moreover, we employ the concept of hard factorization problem (HFP) in the termination phase to against fraud termination requests. Theoretical security analysis discussed in later section indicates the scheme supports mutual authentication and is robust against several attacks such as verifiers' impersonation, replay attack, denial-of-services (DoS) attack and so on.

• 한국정보통신설비학회:학술대회논문집
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• 2004.08a
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• pp.181-186
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• 2004

Bluetooth can form many Piconets within the same location. This network topology can cause mutual interferences , and the effect of interference is critical when a tot of Bluetooth networks coexist. In this paper, the performances of Bluetooth networks under mutual interference is analyzed and simulated using the concept of bit error rate (BER)

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.11C
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• pp.883-891
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• 2008

In 2006, Lee and Ahn proposed a matrix-based RFID authentication protocol which eliminates the security problems in HB and $HB^+$ RFID authentication protocols. Their proposed protocol provides the following three merits: (1) it reduces the computational costs of the RFID tag. (2) it reduces the communication overhead between the reader and the tag. (3) it protects the user privacy. However, this paper points out that Lee and Ahn's proposed protocol is insecure to various attacks because it does not provide mutual authentication which the RFID tag does not authenticate the legality of the RFID reader unlike their claims. In addition, this paper proposes an improved matrix-based RFID mutual authentication protocol that can provide the mutual authentication. As a result, the proposed protocol not only can provide strong security and but also guarantee high efficiency because it reduces the communication rounds compare with Lee-Ahn's protocol.