• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.2
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• pp.43-48
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• 2011

Cognitive radio is accepted as an effective and promising approach for resolving the spectrum scarcity problem by allowing secondary users to borrow unused spectrum from primary users. A method of identifying busy and empty spectrum at the given time and space, which is called spectrum sensing, constitutes an essential element of the cognitive radio. In this paper, we propose a receiver-centric spectrum sensing scheme which attempts to detect the primary receiver rather than the primary transmitter. It is shown that the proposed receiver-centric sensing approach results in more efficient spectrum utilization than the conventional transmitter-centric sensing.

• Convergence Security Journal
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• v.14 no.6_1
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• pp.33-43
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• 2014

In this study, diagnosis of the problem of self-directed learning for the improvement of the language, reasoning n eeded for NCOs typical for students currently enrolled as a cadet NCOs and suggested some lessons to improve this model. Proposed presentation, the three curriculum of presentation and discussion related to the configuration intervie w, self-directed learning was to be his students. In one of the ways to solve the problems experienced in a self-pac ed learning learner was used in this process is often the scaffolding system, is shown that can lead to improved abil ity to apply the result of expression of the three class model.

• Convergence Security Journal
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• v.18 no.2
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• pp.141-148
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• 2018

For soldiers, physical strength can be said to be a prerequisite for military spirit and combat skills, which is a prerequisite for combat skills, which can be maintained and promoted through regular physical exercises and exercises. It is expected to help students improve their stamina by providing training programs for military personnel and students who have worked on physical training programs to strengthen physical fitness programs for students and students, and utilize physical training programs for military discipline and fitness classes to improve military readiness in preparation for military training.

• The Journal of the Korea Contents Association
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• v.15 no.4
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• pp.303-315
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• 2015

This study aimed to examine structural relationship among role stresses (i.e., role conflict, role ambiguity), burnout, depression, and turnover intention among non-commissioned officers. A total 299 non-commissioned officers were participated in this study. Correlation analysis through SPSS WIN 18.0 and SEM through Amos 20.0 were conducted. The results showed that role stresses were significantly positive correlated with burnout, depression, and turnover intention. In addition, it was found that burnout mediated partially between role conflict and turnover intention. It was also revealed that burnout mediated fully between role ambiguity and depression and between role ambiguity and turnover intention as well as between role conflict and depression. From above the results, the implications of this study was discussed in terms of the necessity for building strategy to decrease turnover intention and depression of non-commissioned officers. Finally, limitations and suggestions for further researches were discussed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.2A
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• pp.132-138
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• 2009

Cognitive radio is considered as a promising solution to scarce spectrum problem. The primary object of cognitive radio is to increase spectral efficiency, while causing limited interference to primary users who are using the spectrum. Hence, an essential part of cognitive radio systems is spectrum sensing which determines whether a particular spectrum is occupied or not by a primary user at a particular time. However, sensing decision of each individual secondary user alone may not be reliable enough due to shadowing and multipath fading of wireless channels. The so called hidden terminal problem makes the problem even worse, possibly yielding undesired interference to the primary users. Recently, cooperative spectrum sensing is emerging as a remedy to these problems of individual sensing. Cooperative sensing allows a group of secondary users to share local sensing information to extract a global decision with high fidelity. In this paper, we investigate a cooperative spectrum sensing algorithm based on hard decisions of local sensing outcomes. Specifically, we propose an effective scheme for combining local decisions by introducing weighting factors that reflect reliability of the corresponding secondary user. Through computer simulations, the performance of the proposed combining scheme is compared with that of the conventional scheme without weighting factors in various environments.

• Convergence Security Journal
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• v.18 no.5_2
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• pp.73-82
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• 2018

The goal of this study is to look deeper into a read-write education method for improving communication abilities of petty officer majoring students in community colleague level. The read-write education method improves reading and writing abilities at the same time. Therefore, the read-write education method is modified to a 'read-write-correction' education method and the method is planed proper ways to run the course of the education. A writing report class method which is based on 'read-write' education method is the key process of this education. the education method suggests directions of a taking memo and a guideline of summarizing from the reading part, and the directions of a taking memo and a guideline of summarizing are used on report writings class from the writing part of the 'read-write' education method. The correction part of the education method is controlled by instructors under a process of the 'read-write-correction.' The read-write education method by using the report writing helps to improve communication abilities in work fields because the report writing is based on utilizing document formats that can be used future in petty officer work filed. For the last, the study mentions a proposal for further tasks on this field of the study.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2010.07a
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• pp.119-122
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• 2010

Cognitive Radioo(CR)기술은 주파수 자원을 효율적으로 이용하기 위해 Joseph Mitora가 개념을 적립한 것으로 유비쿼터스 시대의 부족한 주파수 자원을 극복 할 수 있는 기술로 각광받고 있다. 이와 같은 무선인지 기술(CR)을 도입하기 위한 핵심적인 요소는 부사용자(Secondary User)가 주사용자(Primary User)의 통신을 방해하지 않도록 주파수 점유 여부를 정확하게 판단하는 Spectrum Sensing기술이다. 이 스펙트럼 센싱 기술에 두 가지 종류의 에러가 발생하는데 하나는 미검출 오류(miss error)이고 또 하나는 오경보 오류(false alarm error)이다. 따라서 본 논문은 이 두 가지를 합친 검출 오류(detection error)를 최소화 하기위해 협력 스펙트럼 센싱(Cooperative spectrum sensing)에서 몇 명 이상의 부사용자가 주사용자가 사용중이라 검출하였을 때 최종 결정이 주사용자가 사용한다고 결론 짓는 것이 최적인지를 수학적으로 분석하고 그 최적의 K값을 사용하여 전체 시스템의 성능을 향상 시키는 방법을 제시 한다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.626-628
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• 2012

In this paper, we propose a cooperative spectrum sensing scheme using the spatial diversity of secondary users (SUs). In our scheme, a SU makes an estimation whether the primary user (PU) is active or not using the signals from the other SUs. We know that the diversity order of miss detection probability increases as the number of SUs increases from the simulation result.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2000.06a
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• pp.116-123
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• 2000

한국어 구문 분석은 체언구 부착이나 부사구 부착의 문제를 가진다. 이런 부착의 문제는 많은 구문 모호성을 만들어 내어 올바른 의미를 가지는 파스 트리의 선택을 어렵게 한다. 한국어에서 이런 부착의 문제는 대부분 한국어 문장이 내포문을 포함하는 복문의 형태로 구성되어 있기 때문이다. 단문에서는 부착의 문제가 발생하지 않지만 복문에서는 체언구나 부사구가 어떤 용언에 부착하느냐에 따라 체언구 부착이나 부사구 부착의 문제가 발생한다. 따라서 용언이 가지는 정보를 이용하여 내포문의 범위를 결정해서 하나의 구문범주의 기능을 가지도록 분할한다. 이를 단문 분할이라 하며 문형이 가지는 필수격들을 최대로 부착하여 이루어진다. 단문분할을 하면 복문의 구조가 단문으로 바뀌므로 이런 부착의 문제가 자연스럽게 해결된다. 본 논문에서는 문형과 단문 분할을 이용하여 많은 구문 모호성을 해결할 수 있음을 제안한다.

• Annual Conference on Human and Language Technology
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• 2000.10d
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• pp.116-123
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• 2000

한국어 구문 분석은 체언구 부착이나 부사구 부착의 문제를 가진다. 이런 부착의 문제는 많은 구문 모호성을 만들어 내어 올바른 의미를 가지는 파스 트리의 선택을 어렵게 한다. 한국어에서 이런 부착의 문제는 대부분 한국어 문장이 내포문을 포함하는 복문의 형태로 구성되어 있기 때문이다. 단문에서는 부착의 문제가 발생하지 않지만 복문에서는 체언구나 부사구가 어떤 용언에 부착하느냐에 따라 체언구 부착이나 부사구 부착의 문제가 발생한다. 따라서 용언이 가지는 정보를 이용하여 내포문의 범위를 결정해서 하나의 구문범주의 기능을 가지도록 분할한다. 이를 단문 분할이라 하며 문형이 가지는 필수격들을 최대로 부착하여 이루어진다. 단문분할을 하면 복문의 구조가 단문으로 바뀌므로 이런 부착의 문제가 자연스럽게 해결된다. 본 논문에서는 문형과 단문 분할을 이용하여 많은 구문 모호성을 해결할 수 있음을 제안한다.