• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권9호
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• pp.4220-4241
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• 2017

For the downlink energy-harvesting small cell network, this paper proposes an interference management algorithm based on distributed coalitional game. The cooperative interference management problem of the energy-harvesting small cells is modeled as a coalitional game with transfer utility. Based on the energy harvesting strategy of the small cells, the time sharing mode of the small cells in the same coalition is determined, and an optimization model is constructed to maximize the total system rate of the energy-harvesting small cells. Using the distributed algorithm for coalition formation proposed in this paper, the stable coalition structure, optimal time sharing strategy and optimal power distribution are found to maximize the total utility of the small cell system. The performance of the proposed algorithm is discussed and analyzed finally, and it is proved that this algorithm can converge to a stable coalition structure with reasonable complexity. The simulations show that the total system rate of the proposed algorithm is superior to that of the non-cooperative algorithm in the case of dense deployment of small cells, and the proposed algorithm can converge quickly.

• 대한지구과학교육학회지
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• 제2권1호
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• pp.41-47
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• 2009

This study examined the difference for the ability of self-directed learning and information literacy(the ability to use information) between small group-cooperative instruction of ICT practical environment and explanatory instruction using ICT of general classroom in middle school science education. The 138 students(7th grade) participated in this study were classified in two group, experimental group(68) and controlled group(70). Experimental small group consisted of 5-6 students who had different levels and the ability of each the group was equal. The teaching of experimental group was made in the science lab which was equipped with computers to connect super high-speed Internet. The teaching of control group was made in general classroom. Under these two environment, this study was executed during 10 weeks. As the result, Small group-cooperative learning using ICT was more effective in diminishing the gap of information literacy in middle school students. And in the ability of self-directed learning, the small group learning using ICT was also more effective than general classroom instruction.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권2호
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• pp.611-627
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• 2017

For enhancing the coverage of wireless networks and increasing the spectrum efficiency, small cell networks (SCNs) are considered to be one of the most prospective schemes. Most of the existing literature on resource allocation among non-cooperative small cell base stations (SBSs) has widely drawn close attention and there are only a small number of the cooperative ideas in SCNs. Based on the motivation, we further investigate the cooperative approach, which is formulated as a coalition formation game with power control algorithm (CFG-PC). First, we formulate the downlink sub-channel resource allocation problem in an SCN as a coalition formation game. Pareto order and utilitarian order are applied to form coalitions respectively. Second, to achieve more availability and efficiency power assignment, we expand and solve the power control using particle swarm optimization (PSO). Finally, with our proposed algorithm, each SBS can cooperatively work and eventually converge to a stable SBS partition. As far as the transmit rate of per SBS and the system rate are concerned respectively, simulation results indicate that our proposed CFG-PC has a significant advantage, relative to a classical coalition formation algorithm and the non-cooperative case.

• 한국임상수의학회:학술대회논문집
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• 한국임상수의학회 2007년도 춘계학술대회
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• pp.122-122
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• 2007

• Journal of applied mathematics & informatics
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• 제27권3_4호
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• pp.809-817
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• 2009

We call a cycle C be a small cycle if the length of C equals to 3 or 4. In this paper, we obtain two sufficient conditions to ensure the existence of vertex-disjoint small cycles in graph and propose several problems.

• Journal of Gastric Cancer
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• 제10권3호
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• pp.137-140
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• 2010

Gastrointestinal stromal tumors (GISTs) constitute the most common primary mesenchymal tumors of the digestive tract and characteristically express c-kit (CD117). GISTs are the most common non-epithelial tumor of the GI tract and frequently originate from the stomach and small bowel. Specifically, the synchronous occurrence of a GIST with other epithelial tumors is rarely reported. Recently, we discovered one case of a concurrent gastric cancer and a small bowel GIST that was initially suspected to be peritoneal seeding from gastric cancer. The patient was initially admitted with epigastric pain. Gastric cancer with peritoneal seeding was suspected after an evaluation. Following a laparoscopic examination, a distal gastrectomy with D2 lymph node dissection and small-intestine segmental resection was performed. The final pathologic diagnosis was early gastric cancer and high-risk small bowel GIST. The patient refused adjuvant therapy for the GIST, and currently shows no other marked indisposition. He has been disease-free for 14 months.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권1호
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• pp.222-236
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• 2019

Wireless content caching in small cell networks has recently been considered as a promising way to alleviate the congestion of the backhaul in emerging heterogenous cellular network. However, how to select files which are cached in SBSs and how to make SBSs work together is an important issue for cooperative cache research for the propose of reducing file download time. In this paper, a Cooperative-Greedy strategy (CGS) among cache-enabled small base stations (SBSs) in small cell network is proposed, in order to minimize the download time of files. This problem is formulated as a Chinese restaurant game.Using this game model, we can configure file caching schemes based on file popularity and the spectrum resources allocated to several adjacent SBSs. Both the existence and uniquencess of a Nash equilibrium are proved. In the theoretical analysis section, SBSs cooperate with each other in order to cache popular files as many as possible near UEs. Simulation results show that the CGS scheme outperforms other schemes in terms of the file-download time.

• 한국학교보건학회지
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• 제28권2호
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• pp.67-78
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• 2015

The purpose of the study was to present a model of WHO Health Promoting School easily applicable to small-sized schools in rural areas. Methods: The study analyzed data of 11 small-sized schools in rural areas selected from 85 health promoting schools, an initiative led by the Ministry of Education from 2012 to 2014. Results: Through the analysis, the study found out the operation process of health promoting schools consists of five stages: system development, needs survey & survey on current status, school health policy development, program development & execution, and evaluation. In addition, the study was able to discover three key factors in operating health promoting schools: connection with curriculum, connection with community, and consensus among members. While it turned out the schools were following operation manuals faithfully, the biggest problem with operation was that the stages of needs survey, priority setting, and core task development were not closely coordinated. Conclusion: Although the model suggested in the study fails to reflect the characteristics of small-sized schools in rural areas, it is close to a universal model which could serve as a guideline when regular schools adopt the system of health promoting schools.

• 대한공업교육학회지
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• 제33권2호
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• pp.72-96
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• 2008

본 연구에서는 "기업 공고 연계 맞춤형 인력양성 프로그램"에 참여하고 있는 공고와 중소기업의 담당자의 설문 조사를 통하여 프로그램 운영 실태와 문제점 등을 조사 분석 하였다. 본 연구를 통해 분석한 결과는 다음과 같다. 첫째, "기업 공고 연계 맞춤형 인력양성 프로그램"의 목적에 대하여 교사들은 '산 학 연계를 통한 직업교육의 활성화'를 목적으로 인식하였고, 산업체 담당자들은 '중소기업에 전문 인력공급'이라는 목적으로 인식하고 있었다. 둘째, 교사들은 프로그램 운영이 학생들의 직무수행능력 향상 정도에 대하여는 대체로 긍정적으로 응답하고 있었으나, '우수학생 유치'에 있어서는 도움이 되지 못하고 있다고 인식하였다. 셋째, 산업체 담당자들은 프로그램을 통해 중소기업의 인력 확보, 수익 창출, 취업생의 직무수행능력의 향성 정도, 현장 적응력 및 학교와의 연계 및 상호 협력 관계를 유지하는데 긍정적이라고 인식하고 있었으나, 졸업생들의 기능 숙련도, 문제파악과 해결능력, 설비유지 보수 능력에 대해서는 부족한 면이 있다고 인식하는 것으로 나타났다. 일반적으로, 참여 학교 교사들과 산업체 담당자들은 "기업 공고 연계 맞춤형 인력양성 프로그램" 운영의 효율성과 발전 가능성에 대하여 긍정적으로 인식하고 있는 것으로 나타났다.

• 대한지구과학교육학회지
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• 제4권1호
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• pp.43-56
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• 2011

The purpose of this study is to examine the effects of small group inquiry skills on improving science process skills and attitudes toward science in elementary school science. The research questions of this study were as follows. First, effects of small group inquiry skills on improving science process skills in elementary school science. Second, effects of small group inquiry skills on improving attitudes toward science in elementary school science. The subjects of this study is two classes from 6th grade elementary classes in Busan. The experiment class practiced small group inquiry skills, while the control class practiced self inquiry. To verify the effect of the experiment, ANOVA was conducted. The main findings of this study are as follows. First, the small group inquiry skills gave a significant influence on increasing the science process skills, including the basic science process skills and the integrated science process skills, of students. Especially, among subordinate factors of science process skills between groups, it was effective to increase abilities of observing, reasoning, interpreting data, formulating hypothesis. It is necessary for teachers to make an effort to teach according to steps of the small group inquiry skills and to support inquiry activities, in order to increasing the science process skills. However, frequency of additional lessons have a little influence on increasing the science process skills. Second, there is meaningful change in the attitudes toward science for those who studied the small group inquiry skills. Also, they affected subordinate factors of the attitudes toward science, like the attitudes toward science inquiry, the happiness about science class. This study shows that the small group inquiry skills give a positive influence on the science process skills and attitudes toward science in elementary school science.