プライマリシステムの干渉制限を考慮した周波数共用のためのリソース割り当てに関する研究

In wireless communications, the improvement of spectral efficiency isrequired due to the shortage of frequency resource. As an effectivesolution, spectrum sharing has been attracted attention. A cognitiveradio is promising technology for realization of spectrum sharing. Inthe spectrum sharing, cognitive user (secondary user) has to protectlicensed user (primary user) according to the interference constraint.However, conventional metric of interference constraint cannot avoidlarge performance degradation in primary system with widely rangeof Signal to Noise Ratio (SNR) such as a cellular system. Additionally,conventional interference constraints do not considers schedulingbehavior in cellular system. In order to solve these problems, thispaper proposes novel metric of the interference constraint whichsupports the widely SNR region of the primary system, so calledcapacity conservation ratio (CCR). The CCR is defined as the ratio ofthe capacity of the Primary receiver without interference from thesecondary transmitter, to the decreased primary capacity due tointerference. Proposed interference constraint based on CCR canprotect primary capacities over the widely SNR region. In addition,scheduling behavior of the primary system can be protected by usingproposed interference constraint. In addition, we propose transmitpower control schemes: exact and simplified power control. The exactpower control can satisfy requirement of interference constraintwithout large margin; however, transmit power cannot be derivewithout numerical analysis. In contrast, transmit power isclosed-form solution in the simplified power control with satisfyingthe interference constraint. Finally, this thesis proposes the resourcescheduling under the interference constraint. Proposed schedulingachieves the high throughput and high user fairness in the secondarysystem without increasing feedback information compared withconventional algorithm.現在、無線通信において周波数リソース不足が深刻な問題となっており、抜本的な対策技術としてコグニティブ周波数共用が注目されている。本論文では、周波数共用において既存システムの周波数帯を他システム（2 次システム）が二次利用するために干渉制限指標及びリソース割り当てに関する研究を行った。一つ目の研究では、既存システムに与える与干渉状態の評価指標について提案を行い，幅広い通信品質の既存システムを保護可能な干渉制限について評価を行った．評価ではシステムのリンクが静的モデルおよび動的なリソース配分で変更される動的モデルを用いた．二つ目の研究では，その干渉制限達成可能な送信電力制御の検討を行った。送信電力制御を行う際に，外部からチャネル情報の一部のみが得られると仮定し，確率的に変動するフェージング要素について所望のアウテージ確率を満足できるように数値解析を行い，厳密設計および簡易設計について提案を行った．三つ目の研究では、既存システムが複数端末に対して無線リソースをスケジューリングするモデルへと拡張し，2 次システムが干渉を回避しつつ，効率的リソース割り当てに関する検討を行った。電気通信大学201

Whether Tis Nobler to Normalize : Increasing Inter-evaluator Consistency in the Evaluation of Oral Communication Based Activities

When totaling evaluation scores in such as oral communication based activities in the case of multiple evaluators who have not been previously trained to given standards, a simple approach to increasing inter-evaluator consistency is the employment of normalization

英語授業におけるドラマ的手法を用いたスピーキング指導についての考察～学生からのフィードバック分析に基いて～

“Dramatized presentations”have been effectively used in the classroom for some time to assist in the learning of language. This paper presents the authors\u27 experience in the use of original dramatized presentations in the classroom based on and around direct student feedback. The authors\u27 experience includes the teaching of English as a second language in Nagasaki, Japan at both private and national universities. Based on this feedback, the use of original dramatized presentations combined with transparent peer to peer feedback and self-evaluations have been found to increase learner motivation as well as student confidence and ability in communicating in English

英語スピーキングの評価方法についての実践的研究－評価数値の統計的標準化についての検討(2)－

In the evaluating of such as presentations in the classroom “peer evaluation” has become increasingly recognized as a potentially valuable part of the overall evaluation process. One of the challenges, however, in the evaluation of any activity involving speech is the aspect of achieving inter-evaluator consistency. In this paper the peer evaluated results of classroom presentations are normalized and the resulting increased inter peer-evaluator consistency is analyzed and discussed