• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권6호
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• pp.1522-1545
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• 2012

Call admission control (CAC) plays an important role in mobile cellular network to guarantee the quality of service (QoS). In this paper, a dynamic hybrid CAC scheme with integrated cutoff priority and handoff queue for mobile cellular network is proposed and some performance metrics are derived. The unique characteristic of the proposed CAC scheme is that it can support any number of service types and that the cutoff thresholds for handoff calls are dynamically adjusted according to the number of service types and service priority index. Moreover, timeouts of handoff calls in queues are also considered in our scheme. By modeling the proposed CAC scheme with a one-dimensional Markov chain (1DMC), some performance metrics are derived, which include new call blocking probability ($P_{nb}$), forced termination probability (PF), average queue length, average waiting time in queue, offered traffic utilization, wireless channel utilization and system performance which is defined as the ratio of channel utilization to Grade of Service (GoS) cost function. In order to validate the correctness of the derived analytical performance metrics, simulation is performed. It is shown that simulation results match closely with the derived analytic results in terms of $P_{nb}$ and PF. And then, to show the advantage of 1DMC modeling for the performance analysis of our proposed CAC scheme, the computing complexity of multi-dimensional Markov chain (MDMC) modeling in performance analysis is analyzed in detail. It is indicated that state-space cardinality, which reflects the computing complexity of MDMC, increases exponentially with the number of service types and total channels in a cell. However, the state-space cardinality of our 1DMC model for performance analysis is unrelated to the number of service types and is determined by total number of channels and queue capacity of the highest priority service in a cell. At last, the performance comparison between our CAC scheme and Mahmoud ASH's scheme is carried out. The results show that our CAC scheme performs well to some extend.

• 한국초등과학교육학회지:초등과학교육
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• 제39권3호
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• pp.399-411
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• 2020

This study aims to explore how elementary students perceive and approach the issue of plastic debris in marine habitats by examining students' perspectives on the ecosystem and environmental solutions. The study was conducted to 143 Grade Four elementary school students in Seoul. After implementing two class-units on plastic waste, students' constructed responses on the problem of and solutions to plastic debris in marine habitats were collected. Data were analyzed through semantic network analysis and the keywords were visualized to reflect their relationships. Furthermore, students' responses on how they perceive environmental problems were further analyzed based on the following analysis criteria: students' perspectives on the ecosystem, the level of complexity of food chain(s), and the scope of their perspective. Also, student responses on environmental solutions were classified to be either at a personal or social level. Through semantic network analysis, keywords identified for students' perceptions on the problem were the sea, plastic, debris, animals, living things, humans, extinction, while keywords extracted for the solutions were plastic, debris, recycling, disposable, and I. Based on the analysis criteria, it was found that students were well aware of the food chain concept, could perceive the ecosystem as having comprised of both biotic and abiotic factors, and could approach the problem beyond the scope of the marine environment. Also, most students mentioned the solutions only at a personal level. Based on the findings, implications on how to move forward in educating environmental issues related to the ecosystem in science education is further discussed.

• 문화기술의 융합
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• 제5권1호
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• pp.451-456
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• 2019

우리사회는 우리나라 학생들의 학업성적과 삶의 만족도가 반비례 한다는 보고가 나와 충격을 받고 있다. 경제협력개발기구(OECD)가 발표한 국제학업성취도평가(PISA) '2015 학생 삶의 질 만족도 보고서'에 의하면 한국 학생들의 학력수준은 OECD 국가 가운데 최상위층이지만 '삶의 만족도'는 비 OECD국가를 포함한 OECD국가 48개국 중 47위로 최하위권으로 나타났다.[1] 이것은 집단적인 성적위주 평가방식의 일방적인 교육이 그 요인이라고 보고 블록 체인 기술을 활용한 개인맞춤형 통합 모델을 연구하고자 한다. 보안성, 투명성, 분산성이 특징인 블록체인 기술을 활용하여 공급자 일방의 교육 및 일방적인 개인성적 공개위주 시스템에서 선택교육 및 개인승인을 통한 개인맞춤형 교육 및 평가시스템 모델을 연구하였다. 이 연구를 통하여 교육의 본질을 고려하면서 개인별 맞춤교육 및 평가관리시스템이 학생 삶의 질 개선에 기여한 의의를 가지고자 한다.

• 대한수학교육학회지:수학교육학연구
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• 제18권3호
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• pp.283-308
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• 2008

기초학력의 부진은 교과 학습 및 사회생활의 장애요인으로 작용한다. 국가적 차원에서는 2002년부터 실시된 '초등학교 3학년 기초학력 진단평가'와 '학습부진학생 책임지도제', 보정교육 자료 개발 등 교육의 복지를 실현하고자 일련의 노력을 기울이고 있다. 기초학력 진단평가의 목적은 학습 결손 원인에 대한 정보 및 개인적 정보를 수집하여 이들을 지도하는데 도움을 주기 위한 것이다. 본 논문에서는 상담기간 축적된 기초학력 진단평가 결과 나타난 미도달 학생들이 특징을 분석하였다. 미도달 학생들은 문항에 포함된 수치적 특징, 받아올림/내림의 여부, 문항의 배치 및 진술 방식, 정보 제시 방식, 개념의 전형적인 예, 친숙도, 일상생활에서의 사용 빈도 등에 상당한 영향을 받는 것으로 나타났다. 본 연구의 결과는 미도달 학생들의 지도 및 보정교육 자료 개발을 위한 근거를 마련해줄 수 있을 것이다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권4호
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• pp.467-476
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• 2019

Objective: This research was conducted to study the genetic diversity in several Indonesian cattle breeds using microsatellite markers to classify the Indonesian cattle breeds. Methods: A total of 229 DNA samples from of 10 cattle breeds were used in this study. The polymerase chain reaction process was conducted using 12 labeled primers. The size of allele was generated using the multiplex DNA fragment analysis. The POPGEN and CERVUS programs were used to obtain the observed number of alleles, effective number of alleles, observed heterozygosity value, expected heterozygosity value, allele frequency, genetic differentiation, the global heterozygote deficit among breeds, and the heterozygote deficit within the breed, gene flow, Hardy-Weinberg equilibrium, and polymorphism information content values. The MEGA program was used to generate a dendrogram that illustrates the relationship among cattle population. Bayesian clustering assignments were analyzed using STRUCTURE program. The GENETIX program was used to perform the correspondence factorial analysis (CFA). The GENALEX program was used to perform the principal coordinates analysis (PCoA) and analysis of molecular variance. The principal component analysis (PCA) was performed using adegenet package of R program. Results: A total of 862 alleles were detected in this study. The INRA23 allele 205 is a specific allele candidate for the Sumba Ongole cattle, while the allele 219 is a specific allele candidate for Ongole Grade. This study revealed a very close genetic relationship between the Ongole Grade and Sumba Ongole cattle and between the Madura and Pasundan cattle. The results from the CFA, PCoA, and PCA analysis in this study provide scientific evidence regarding the genetic relationship between Banteng and Bali cattle. According to the genetic relationship, the Pesisir cattle were classified as Bos indicus cattle. Conclusion: All identified alleles in this study were able to classify the cattle population into three clusters i.e. Bos taurus cluster (Simmental Purebred, Simmental Crossbred, and Holstein Friesian cattle); Bos indicus cluster (Sumba Ongole, Ongole Grade, Madura, Pasundan, and Pesisir cattle); and Bos javanicus cluster (Banteng and Bali cattle).

• 한국산학기술학회논문지
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• 제21권1호
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• pp.148-154
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• 2020

본 논문에서는 대학 기숙사에서 이용 빈도가 높은 특정 공용 공간의 접근성을 높이기 위한 공실 배정에 대해 고려한다. 접근성 향상을 위하여, 학년에 따른 이용 빈도의 차이를 반영하여 학생들의 개인 공실에서 특정 공용 공간까지의 총 이동거리를 최소화하는 정수계획법 모델을 제시한다. 또한 각 공실의 최대 허용 인원을 제한하고 하나의 공실에는 같은 학년으로만 배정되도록 제약하였으며, 제시된 모델은 공급사슬관리에서 다루는 입지 선정 문제와 유사함을 보여준다. 사례 연구를 위하여 제시된 정수계획법 모델을 A대학교 기숙사에 적용하여, 소규모 그룹에 대한 공실 배정 결과를 도출하였으며, 특정 공용 격실을 이용하는 횟수가 많은 저학년 학생일수록 접근성을 고려하여 가까운 곳에 배정되었음을 확인하였다. 추가적으로 고학년부터 공실 배정에 대한 우선순위를 부여할 경우, 저학년이 우선적으로 배정될 때 벌과비용을 목적함수에 추가함으로써 이를 방지하도록 하는 모델을 제시하였다. 이러한 결과를 바탕으로 여러 공용 공간에 대한 학생들의 복합적인 요구들에 부합하도록 공실을 배정하는 방안을 제시할 수 있다.

• Journal of Microbiology and Biotechnology
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• 제12권3호
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• pp.423-430
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• 2002

The effects of UV-B and commercial grade pesticides (butachlor and carbofuran), individually and in combination, were studied on a variety of physiological processes of rice field cyanobacterium Anabaena doliolum. Butachlor was found to be $2-12\%$ more toxic than carbofuran and $4-24\%$ than UV-B on the growth, photosynthesis, lipid peroxidation, membrane permeability, and nitrogenase activity of the test cyanobacterium. Of the three photosynthesis inhibitors, the butachlor-induced inhibition of whole chain was approximately 3 and $21\%$ higher than carbofuran and UV-B, respectively. Although the interaction of the stress factors caused a significant inhibition (P<0.01), it was still less than the additive effect on the parameters investigated, except for PSI.

• Pediatric Infection and Vaccine
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• 제22권1호
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• pp.1-6
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• 2015

목적: 최근 일개 고등학교(S 고등학교)에서 유행성이하선염이 집단발병 하였기에 본 연구에서는 S 고등학교의 발생 현황을 알아보고 진단을 위해 시행한 PCR 검사의 역학적 유용성에 대해 알아보고자 한다. 방법: 2013년 4-7월 유행성이하선염이 의심되어 의료기관을 방문한 S 고등학교 학생들의 월별 분포와 학년별 수를 조사 하였고 이중 일부 학생에게 PCR 검사를 시행하였다. 결과: 총 77명이 의료기관을 방문하였고 월별로 4월 1명, 5월 17명, 6월 45명, 7월 5명, 학년별로 1학년 26명, 2학년 28명, 3학년 23명이었다. 볼점막도찰 PCR 검사를 받은 18명 중 15명은 증상 발생 3일 이내에 검체를 채취하여 그 중 5명(33.3%)이 양성이었고 나머지 3명은 3일 이후에 검체를 채취하여 모두 음성이었다(P=0.24). 결론: 본 저자들은 S 고등학교의 유행성이하선염의 집단발병 양상을 조사하였다. PCR 검사는 증상 발생 후 3일 이내 시행하면 역학 조사시 도움이 될 가능성이 있겠다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권10호
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• pp.5651-5655
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• 2013

Objective: Major histocompatibility complex class I chain-related A (MICA) is a stress-inducible glycoprotein that can be shed as a soluble protein. This study was conducted to determine the expression of MICA in renal cell carcinoma (RCC) and examine the clinical relevance of soluble MICA (sMICA) in this disease. Methods: Immunohistochemistry and real-time PCR analyses were performed to assess the expression of MICA in 48 pairs of RCC and adjacent normal renal tissues. Serum levels of sMICA were measured in 48 RCC patients, 12 patients with benign renal tumors, and 20 healthy individuals. The correlations between sMICA levels and clinicopathological parameters were analyzed and the diagnostic performance of sMICA in RCC was evaluated. Results: RCCs exhibited elevated expression of MICA compared to adjacent normal tissues. Serum concentrations of sMICA were significantly greater in RCC patients ($348.5{\pm}32.5pg/ml$) than those with benign disease ($289.3{\pm}30.4pg/ml$) and healthy controls ($168.4{\pm}43.2pg/ml$) and significantly correlated with advanced tumor stage, lymph node metastasis, distant metastasis, vascular invasion, and higher histological grade. Using a cut-off point of 250 pg/ml, sMICA demonstrated a specificity and sensitivity of 63.2% and 75.6%, respectively, in distinguishing between RCC and benign renal tumors. Conclusion: MICA expression is upregulated in RCC and increased serum sMICA levels predict aggressive tumor behavior. However, the applicability of sMICA alone is limited in distinguishing RCC from benign renal tumors.

• Journal of Periodontal and Implant Science
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• 제52권2호
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• pp.116-126
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• 2022

Purpose: This study evaluated the efficacy of treating periodontitis using subgingival nano-hydroxyapatite powder with an air abrasion device (NHAPA) combined with scaling and root planing (SRP). Methods: A total of 28 patients with stage III periodontitis (grade B) were included in this study, although 1 was lost during follow-up and 3 used antibiotics. The patients were divided into a test group and a control group. All patients first received whole-mouth SRP using hand instruments, and a split-mouth approach was used for the second treatment. In the test group, the teeth were treated with NHAPA for 15 seconds at 70% power per pocket. Subgingival plaque samples were obtained from the 2 deepest pockets at the test and control sites before treatment (baseline) and 3 months after treatment. The full-mouth plaque index (PI), gingival index (GI), papillary bleeding index (PBI), bleeding on probing (BOP), probing depth (PD) and clinical attachment level (CAL) were recorded at baseline and at 1- and 3-month post-treatment. Real-time polymerase chain reaction was used to determine the colonisation of Treponema denticola (Td), Porphyromonas gingivalis (Pg), and Aggregatibacter actinomycetemcomitans in the subgingival plaque. Results: From baseline to the first month, the test group showed significantly larger changes in BOP and CAL (43.705%±27.495% and 1.160±0.747 mm, respectively) than the control group (36.311%±27.599% and 0.947±0.635 mm, respectively). Periodontal parameters had improved in both groups at 3 months. The reductions of PI, GI, BOP, PD, and CAL in the test group at 3 months were greater and statistically significant. The total bacterial count and Td and Pg species had decreased significantly by the third month in both groups (P<0.05). Conclusions: Applying NHAPA in addition to SRP improves clinical periodontal parameters more than SRP alone. Subgingival NHAPA may encourage clot adhesion to tooth surfaces by increasing surface wettability.