• IMMUNE NETWORK
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• v.6 no.2
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• pp.93-101
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• 2006

Background: Memory T lymphocytes of the immune system provide long-term protection in response to bacterial or viral infections/immunization. Ag concentration has also been postulated to be important in determining whether T cell differentiation favors effector versus memory cell development. In the present study we hypothesized that naive Ag-specific $CD4^+$ T cells briefly stimulated with different Ag doses at the primary exposure could affect establishment of memory cell pool after secondary immunization. Methods: To assess this hypothesis, the response kinetics of DO11.10 TCR $CD4^+$ T cells primed with different Ag doses in vitro was measured after adoptive transfer to naive BALB/c mice. Results: Maximum expansion was shown in cells primarily stimulated with high doses of ovalbumin peptide $(OVA_{323-339})$, whereas cells in vitro stimulated with low dose were expanded slightly after in vivo secondary exposure. However, the cells primed with low $OVA_{323-339}$ peptide dose showed least contraction and established higher number of memory cells than other treated groups. When the cell division was analyzed after adoptive transfer, the high dose Ag-stimulated donor cells have undergone seven rounds of cell division at 3 days post-adoptive transfer. However, there was very few division in naive and low dose of peptide-treated group. Conclusion: These results suggest that primary stimulation with a low dose of Ag leads to better memory $CD4^+$ T cell generation after secondary immunization. Therefore, these facts imply that optimally primed $CD4^+$ T cells is necessary to support effective memory pool following administration of booster dose in prime-boost vaccination.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1234-1240
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• 2009

This study was to compare the effectiveness and validity of various data-mining algorithm for Sasang type diagnostic test. We compared the sensitivity and specificity index of nine attribute selection and eleven class classification algorithms with 31 data-set characterizing Sasang typology and 10-fold validation methods installed in Waikato Environment Knowledge Analysis (WEKA). The highest classification validity score can be acquired as follows; 69.9 as Percentage Correctly Predicted index with Naive Bayes Classifier, 80 as sensitivity index with LWL/Tae-Eum type, 93.5 as specificity index with Naive Bayes Classifier/So-Eum type. The classification algorithm with highest PCP index of 69.62 after attribute selection was Naive Bayes Classifier. In this study we can find that the best-fit algorithm for traditional medicine is case sensitive and that characteristics of clinical circumstances, and data-mining algorithms and study purpose should be considered to get the highest validity even with the well defined data sets. It is also confirmed that we can't find one-fits-all algorithm and there should be many studies with trials and errors. This study will serve as a pivotal foundation for the development of medical instruments for Pattern Identification and Sasang type diagnosis on the basis of traditional Korean Medicine.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.27 no.5
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• pp.1087-1097
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• 2017

As the penetration rate of smartphones increases, the number of malicious codes targeting smartphones is increasing. I 360 Security 's smartphone malware statistics show that malicious code increased 437 percent in the first quarter of 2016 compared to the fourth quarter of 2015. In particular, malicious applications, which are the main means of distributing malicious code on smartphones, are aimed at leakage of user information, data destruction, and money withdrawal. Often, it is operated by an API, which is an interface that allows you to control the functions provided by the operating system or programming language. In this paper, we propose a mechanism to detect malicious application based on the similarity of API pattern in normal application and malicious application by learning pattern of API in application derived from static analysis. In addition, we show a technique for improving the detection rate and detection rate for each label derived by using the corresponding mechanism for the sample data. In particular, in the case of the proposed mechanism, it is possible to detect when the API pattern of the new malicious application is similar to the previously learned patterns at a certain level. Future researches of various features of the application and applying them to this mechanism are expected to be able to detect new malicious applications of anti-malware system.

• Molecules and Cells
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• v.37 no.1
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• pp.66-73
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• 2014

Myeloid-derived suppressor cells (MDSCs) play an important role in impairing the function of T cells. We characterized MDSCs in two chronic hepatitis C (CHC) cohorts: a cross-sectional group that included 61 treatment-naive patients with CHC, 14 rapid virologic response (RVR) cases and 22 early virologic response (EVR) cases; and a longitudinal group of 13 cases of RVR and 10 cases of EVR after pegylated-interferon-${\alpha}$/ribavirin treatment for genotype 1b HCV infection. Liver samples from 32 CHC patients and six healthy controls were subjected to immunohistochemical analysis. MDSCs frequency in treatment-naive CHC was significantly higher than in RVR, EVR, or healthy subjects and was positively correlated with HCV RNA. Patients infected with HCV genotype 2a had a significantly higher frequency of MDSCs than those infected with genotype 1b. Decreased T cell receptor (TCR) ${\zeta}$ expression on $CD8^+$ T cells was significantly associated with an increased frequency of MDSCs in treatment-naive CHC patients and was restored by L-arginine treatment in vitro. Increased numbers of liver arginase-$1^+$ cells were closely associated with the histological activity index in CHC. The TCR ${\zeta}$ chain was significantly downregulated on hepatic $CD8^+$ T cells in CHC. During antiviral follow up, MDSCs frequency in peripheral blood mononuclear cells was directly correlated with the HCV RNA load in the plasma and inversely correlated with TCR ${\zeta}$ chain expression in $CD8^+$ T cells in both RVR and EVR cases. Notably, the RVR group had a higher frequency of MDSCs at baseline than the EVR group. Collectively, this study provides evidence that MDSCs might be associated with HCV persistence and downregulation of CD8 ${\zeta}$ chain expression.

• Phonetics and Speech Sciences
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• v.14 no.1
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• pp.21-28
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• 2022

Previous studies have provided important findings on children's speech production development. They have revealed that essentially all aspects of children's speech shift toward adult-like characteristics over time. Nevertheless, few studies have examined the perceptual aspects of children's speech tokens, as perceived by naive adult listeners. To fill the gap between children's production and adults' perception, we conducted cross-sectional perceptual studies of monosyllabic words produced by children aged two to six years. Monosyllabic words in the consonant-vowel-consonant form were extracted from children's speech samples and presented aurally to five listener groups (20 listeners in total). Generally, the agreement rate between children's production of target words and adult listeners' responses increases with age. The perceptual responses to tokens produced by two-year old children induced the largest discrepancies and the responses to words produced by six years olds agreed the most. Further analyses were conducted to identify the sources of disagreement, including the types of segments and syllable structure. This study makes an important contribution to our understanding of the development and perception of children's speech across age groups.

• Journal of Nutrition and Health
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• v.27 no.10
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• pp.979-987
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• 1994

We have examined the antigen specificity in orally tolerant mice fed with the casein(CN) diet. In contrast to previous reported results of studies on oral tolerance, these mice responded poorly to ovalbumin(OVA) and ovomucoid(OM), as well as $\alpha$sl-enriched fraction of these cells suppressed anti $\alpha$sl-CN antibody production of naive mice, but could not significantly suppressed antibody response of previously immunized recipient mice. These results indicate that oral tolerance was not medicate through suppressor T cell activities.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10b
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• pp.127-129
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• 2001

입력된 문장을 분석하여 미리 정해진 범주에 따라 그 문장의 감정 상태의 천이를 출력해 주는 감정인식 시스템을 제안한다. Naive Bayes 알고리즘을 사용했던 이전 방법과 달리 새로 연구된 시스템은 Hidden Markov Model(HMM)을 사용한다. HMM은 특정 분포로 발생하는 현상에서 그 현상의 원인이 되는 상태의 천이를 찾아내는데 적합한 방법으로서, 하나의 문장에 여러 가지 감정이 표현된다는 가정 하에 감정인식에 관한 이상적인 알고리즘이라 할 수 있다. 본 논문에서는 HMM을 사용한 감정인식 시스템에 관한 개요를 설명하고 이전 버전에 비해 보다 향상된 실험결과를 보여준다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1991.10a
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• pp.469-474
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• 1991

Recent interests in intelligent LP modeling aim to support MS/OR-naive users to be able to apply LP models to practical problems without the expert knowledges required. For more generalized LP modeling, a GPS(General Problem Solver)-based approach is suggested in this paper. It identifies modeling process as a means-ends analysis process. In view of this approach, a) we first divide the knowledges into domain specific assertive knowledges(state) and procedural knowledges about LP modeling(operator and macro) for model-domain independence, b) and then generate LP model according to the difference resolution techniques.

• Proceedings of the Korean Information Science Society Conference
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• 2000.04b
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• pp.466-468
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• 2000

이 논문에서는 Helmholtz machine을 사용하여 데이터의 분포 추정을 함으로써 문서 분류기를 학습하는 방법 제안한다. Helmholtz machine 은 생성 모델과 인식 모델로 구성된 그래프 모델로서, 그래프 모델에서의 분포 추정을 보다 가능하게 하기 위한 근사 방법 중의 하나이다. Helmholtz machine에서의 각 입력 노드는 문서를 구성하는 하나의 단어에 대응하는 이진 노드이다. 입력 노드의 개수가 많아지면 그만큼 학습 시간이 증가하기 때문에, 학습 시간을 줄이면서 적정 수준의 성능을 유지하기 위해 자질 선정이 필요하다. 이러한 요구 사항을 충족시키기 위해 정보획득량(information gain)기준을 이용하였으며, 뉴스 그룹 데이터에 대해 그 성능을 측정하고 Naive Bayes를 이용한 것과 비교한다.

• The Pure and Applied Mathematics
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• v.14 no.3
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• pp.191-196
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• 2007

The main components in the generalized Mandelbrot sets are under a theoretical investigation for their parametric boundary equations. Using the boundary geometries, a fast construction algorithm is introduced for the generalized Mandelbrot set. This fast algorithm definitely reduces the construction CPU time in comparison with the naive algorithm. Its graphic implementation displays the mysterious and beautiful fractal sets.