• Title/Summary/Keyword: problem analysis

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A Centralized Deployment Protocol with Sufficient Coverage and Connectivity Guarantee for WSNs (무선 센서 네트워크에서 유효 커버리지 및 접속성 보장을 위한 중앙 집중형 배치 프로토콜)

  • Kim, Hyun-Tae;Zhang, Gui-Ping;Kim, Hyoung-Jin;Joo, Young-Hoon;Ra, In-Ho
    • Journal of the Korean Institute of Intelligent Systems
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    • v.16 no.6
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    • pp.683-690
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    • 2006
  • Reducing power consumption to extend network lifetime is one of the most important challenges in designing wireless sensor networks. One promising approach to conserving system energy is to keep only a minimal number of sensors active and put others into low-powered sleep mode, while the active sensors can maintain a connected covet set for the target area. The problem of computing such minimum working sensor set is NP-hard. In this paper, a centralized Voronoi tessellation (CVT) based approximate algorithm is proposed to construct the near optimal cover set. When sensor's communication radius is at least twice of its sensing radius, the covet set is connected at the same time; In case of sensor's communication radius is smaller than twice of its sensing radius, a connection scheme is proposed to calculate the assistant nodes needed for constructing the connectivity of the cover set. Finally, the performance of the proposed algorithm is evaluated through theoretical analysis and extensive numerical experiments. Experimental results show that the proposed algorithm outperforms the greedy algorithm in terms of the runtime and the size of the constructed connected cover set.

A Comparative Experiment on Dimensional Reduction Methods Applicable for Dissimilarity-Based Classifications (비유사도-기반 분류를 위한 차원 축소방법의 비교 실험)

  • Kim, Sang-Woon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.3
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    • pp.59-66
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    • 2016
  • This paper presents an empirical evaluation on dimensionality reduction strategies by which dissimilarity-based classifications (DBC) can be implemented efficiently. In DBC, classification is not based on feature measurements of individual objects (a set of attributes), but rather on a suitable dissimilarity measure among the individual objects (pair-wise object comparisons). One problem of DBC is the high dimensionality of the dissimilarity space when a lots of objects are treated. To address this issue, two kinds of solutions have been proposed in the literature: prototype selection (PS)-based methods and dimension reduction (DR)-based methods. In this paper, instead of utilizing the PS-based or DR-based methods, a way of performing DBC in Eigen spaces (ES) is considered and empirically compared. In ES-based DBC, classifications are performed as follows: first, a set of principal eigenvectors is extracted from the training data set using a principal component analysis; second, an Eigen space is expanded using a subset of the extracted and selected Eigen vectors; third, after measuring distances among the projected objects in the Eigen space using $l_p$-norms as the dissimilarity, classification is performed. The experimental results, which are obtained using the nearest neighbor rule with artificial and real-life benchmark data sets, demonstrate that when the dimensionality of the Eigen spaces has been selected appropriately, compared to the PS-based and DR-based methods, the performance of the ES-based DBC can be improved in terms of the classification accuracy.

Relationship of Orofacial Pain and Sleep Quality (수면의 질과 구강 안면 통증의 관계)

  • Lee, You-Mee
    • Journal of Oral Medicine and Pain
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    • v.31 no.1
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    • pp.91-99
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    • 2006
  • This study was performed to investigate about sleep quality and orofacial pain pattern between experimental and control group. 101 subjects with temporomandibular disorders without any psychologic and neurologic problem were selected from the patients presented to Wonkwang University dental hospital. Routine clinical examination for TMD was carried out, especially for the frequency of headache and the craniocervical muscles were also done by the author in the first visit. All the subjects filled out the questionnaires, that was, for the evaluation of sleep quality using Pittsburgh sleep quality index(PSQI), and for the analysis of behavioral pain scale questionnaires. Data obtained were statistically processed by the SPSS Windows program and the results of this study were as follows: 1. Subjective sleep index, sleep latency, sleep disturbance, global score in control group were significantly lower than 2. Subjective sleep index, sleep disturbance, global score in subject with headache were significantly lower than subject without headache(P<0.05). 3. Medicine taker have sleeping drug. Caffeine drinkers was significantly higher in daytime dysfunction, global score than no drinker. 4. It have more frequent head and neck pain, pain spreading, daily life difficult in poor sleeper than good sleeper.

Violence and an Ethical Figure in Harold Pinter's One for the Road (해롤드 핀터의 『길 떠나기 전 한잔』에 나타난 폭력과 윤리적 주체)

  • Lee, Seon Hyeon
    • English & American cultural studies
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    • v.18 no.4
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    • pp.103-137
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    • 2018
  • Harold Pinter's One for the Road(1984) is a play about violence. Nicholas, who appears to be the manager of a place, interrogates Victor, Nicky, and Victor's wife Gila in a room for one day from morning to night. There is no direct physical violence in this play. But hints about the atrocities that took place outside the stage make the audience guess the violence and cruelty. Violence, which is not seen as such, is the central theme of the play. One for the road is worth reading as a resistance to breaking the mirror of global ideology, not as it deals with violent events confined to Turkey. The problem which Pinter had in mind, in particular, is that the United States plays a leading role in producing world-class ideologies, and that Britain is involved in collusion with the United States in cultivating such ideological fantasies, both abroad and at home. This thesis analyzes the contrasting reactions of each character in the play based on this social context. In particular, the conflicting reactions of the characters on the system are the most important conflict in the drama. Nicolas is a manager who moves on the system without seeing the truth. Victor and his family, on the other hand, do not move within the same ideology as Nicholas. This paper will take a look at what their strategies of resistance is and how they are revealed in the work. In fact, Nicholas appears split. Nicholas seemingly reacted decisively to the interpellation of the system. He expresses his belief and respect for the legitimacy of his actions. However, he has repeatedly sought the respect and love of Victor. Nicholas is now swaying. The theme that Nicholas presents consciously by grabbing at his own sway is 'Patriotism.' But this fantasy splits through Victor's silence and death demands. Therefore, the questions to be answered are: So why does Nicolas appear to be torn apart in a system that directs violence? But why is he forced to assimilate into the system? What other figures imply? To answer these questions, this thesis will take Slavoj Zizek's view of ideology. On the other hand, there are previous studies that read the system of violence in One for the road from the Althusser's perspective. Surely, this play explores the role of Ideological State Apparatus. However, from the point of view of Althusser, it is not possible to read Nicholas's division and the point of resistance seen by Victor's family. Pinter does not limit the scope of the ideological system as a closed one that regenerates ideologies, but secures the domain of main body resistance and struggle. On the other hand, there are already several domestic theses that read Pinter's work in Zizek's perspective. But these theses are mainly focused on analysis of Mountain Language. What this thesis would suggest is that there is a potential for an ethical figure of Zizek to be considered in One for the Road.

A case study of family therapy about conflict between mother and the eldest son (홀어머니와 큰아들의 갈등에 대한 가족치료 사례연구)

  • Park, Tai-young;Kim, Tae-han
    • Korean Journal of Family Social Work
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    • no.23
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    • pp.263-302
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    • 2008
  • The study had four purposes as follows; First, the researcher tried to find the characteristics of conflict. Second, the researcher attempted to find the factors influencing the conflict between mother and the eldest son, Third, the study attempted to find the therapist's intervention techniques, which were caused the change of the conflict between mother and the eldest son. Lastly, the study was to find the changed contents of family relationships. The total family counseling was 13 sessions, which included individual and family counseling. The study used constant comparative analysis by using open coding method to find the factors. Also, the researcher used Miles and Huberman's matrix and graphical network display to show the relationships among factors influencing the conflicts between mother and the eldest son. The study found the boundary problem of family, family's undifferentiated ego, dysfunctional communication patterns, and mother's experience from family of origin as factors influencing the conflict between mother and the eldest son. On the other hand, the study found that the therapist used the formation of therapeutic alliance relationship, guide of communication skills, the reflection of repeated pattern, reframing and a metaphor as intervention methods. The result of study revealed that changed level of family relationship, activating functional communication, changed boundary among family members, differentiated ego of family members, and changed cognition as the changed contents of family relationship.

Application of Multispectral Remotely Sensed Imagery for the Characterization of Complex Coastal Wetland Ecosystems of southern India: A Special Emphasis on Comparing Soft and Hard Classification Methods

  • Shanmugam, Palanisamy;Ahn, Yu-Hwan;Sanjeevi , Shanmugam
    • Korean Journal of Remote Sensing
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    • v.21 no.3
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    • pp.189-211
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    • 2005
  • This paper makes an effort to compare the recently evolved soft classification method based on Linear Spectral Mixture Modeling (LSMM) with the traditional hard classification methods based on Iterative Self-Organizing Data Analysis (ISODATA) and Maximum Likelihood Classification (MLC) algorithms in order to achieve appropriate results for mapping, monitoring and preserving valuable coastal wetland ecosystems of southern India using Indian Remote Sensing Satellite (IRS) 1C/1D LISS-III and Landsat-5 Thematic Mapper image data. ISODATA and MLC methods were attempted on these satellite image data to produce maps of 5, 10, 15 and 20 wetland classes for each of three contrast coastal wetland sites, Pitchavaram, Vedaranniyam and Rameswaram. The accuracy of the derived classes was assessed with the simplest descriptive statistic technique called overall accuracy and a discrete multivariate technique called KAPPA accuracy. ISODATA classification resulted in maps with poor accuracy compared to MLC classification that produced maps with improved accuracy. However, there was a systematic decrease in overall accuracy and KAPPA accuracy, when more number of classes was derived from IRS-1C/1D and Landsat-5 TM imagery by ISODATA and MLC. There were two principal factors for the decreased classification accuracy, namely spectral overlapping/confusion and inadequate spatial resolution of the sensors. Compared to the former, the limited instantaneous field of view (IFOV) of these sensors caused occurrence of number of mixture pixels (mixels) in the image and its effect on the classification process was a major problem to deriving accurate wetland cover types, in spite of the increasing spatial resolution of new generation Earth Observation Sensors (EOS). In order to improve the classification accuracy, a soft classification method based on Linear Spectral Mixture Modeling (LSMM) was described to calculate the spectral mixture and classify IRS-1C/1D LISS-III and Landsat-5 TM Imagery. This method considered number of reflectance end-members that form the scene spectra, followed by the determination of their nature and finally the decomposition of the spectra into their endmembers. To evaluate the LSMM areal estimates, resulted fractional end-members were compared with normalized difference vegetation index (NDVI), ground truth data, as well as those estimates derived from the traditional hard classifier (MLC). The findings revealed that NDVI values and vegetation fractions were positively correlated ($r^2$= 0.96, 0.95 and 0.92 for Rameswaram, Vedaranniyam and Pitchavaram respectively) and NDVI and soil fraction values were negatively correlated ($r^2$ =0.53, 0.39 and 0.13), indicating the reliability of the sub-pixel classification. Comparing with ground truth data, the precision of LSMM for deriving moisture fraction was 92% and 96% for soil fraction. The LSMM in general would seem well suited to locating small wetland habitats which occurred as sub-pixel inclusions, and to representing continuous gradations between different habitat types.

A Study on the Characteristics and Evaluation of the Policy in Japan's recent Reform of Education - Focus on the MEXT and CCE - (일본의 최근 교육개혁 정책의 특징과 평가 - 문부과학성과 중앙교육심의회를 중심으로 -)

  • Ko, Jeon
    • Korean Journal of Comparative Education
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    • v.26 no.4
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    • pp.173-198
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    • 2016
  • The purpose of this study is to analyze the characteristics of Educational Reforms Policy in lately Japan and to evaluate it. Especially focus on the activities of the [MEXT; Ministry of Education, Culture, Sports, Science and Technology] and [CCE;The Central Council for Education] This article composed of five chapters; Implication and problem situation, History of the Japanese educational reforms, the characteristics in the site of process of educational reforms policy, evaluation on the main policies, and Conclusion(contain the suggestion for Korea). The method of study composed of the literature search and interview. The System Analysis[input-process-output-feedback] is used as a model of the analyze the characteristics of educational reforms policy. By the new Basic Act on Education, the principles of educational administration is changed. Education administration shall be carried out in a fair and proper manner through appropriate role sharing and cooperation between the national and local governments(Article 16). As a conclusion, The initiative in the establishment of educational reform plans has gone over to the cabinet side from MEXT. And evaluate the five policies. That is Japan's Basic Plan for the Promotion of Education, The new Basic Act on Education(enacted on 2006), Provincial Governor's (Tokyo & Oska) Educational Reform Plan, Reform plan of the Boards of Education, and Improvement Policy of the Quality of Teachers.

Does the Quantitative Supply of Secondary Teachers Compromise their Quality?: A Comparative Analysis of South Korea and China (한국과 중국의 중등학교 교사 신규채용제도 비교 분석)

  • Kim, Ee-Gyeong;Ahn, Ji-Yoon;Wei, Hua-Ou
    • Korean Journal of Comparative Education
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    • v.24 no.3
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    • pp.157-177
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    • 2014
  • The importance of selection methods of secondary school teachers have gathered attention due to their enormous influence on the pre-service education programs. However, scholars and practitioners are skeptical about the effectiveness of the measures, especially under the condition of teacher oversupply found in South Korea and China. Based on this problem statement, this study seeks to compare the secondary teacher employment methods of the two countries to better understand the situations as well as to draw implications for improvement. We reach the following conclusions through comparative analyses. First, the reforms of the teacher employment system in both countries have been triggered by the quantitative supply concerns not by the qualitative concerns. Second, both countries require teaching license as a precondition of employment, while their quality assurance measures for the license reveal critical limitations. Third, both countries have attempted to improve selection methods; nevertheless, oversupply of prospective teachers makes objectivity and fairness more important than the appropriateness. Based on the conclusions, policy implications focusing on the quality-oriented approach are suggested in order to employ effective secondary teachers who can contribute to the quality improvement of school education.

Analysis of the Context of Inclusion and Awareness of Classical Literature Materials in Literature - With a Focus on High School Literature Textbooks (고전문학 제재의 수록 맥락과 교육적 인식의 탐색 -고등학교 문학 교과서를 대상으로-)

  • Choi, Hong-won
    • Journal of Korean Classical Literature and Education
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    • no.35
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    • pp.5-46
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    • 2017
  • This study aims to investigate the context of materials in literature textbooks and the awareness about the educational value of classical literature, as part of an interest in literature education phenomena. This study accepts the premise that textbooks affect the practice of classical literature education and, in particular, materials in textbooks are chosen according to the intentions, demands, and perspectives of education in specific social conditions. I divided the educational value of classical literature into two categories, classical and literary value, and investigated the actual conditions and context of materials of literature textbooks based on the 2009 revised curriculum and the 2011 revised curriculum. Classical literature is generally alienated and excluded; contemporary literature materials are mostly included and organized in the domains of 'the role of literature', 'reception and production of literature' and 'literature and life.' In addition, the tendency to heighten classical value and diminish literary value is deepening. In order to solve the problem that classical literature is only included as the product of the past, changes must be made not just to the curriculum, which are external changes, but to the awareness of the essence of classical literature, which are internal changes. Above all, generality as 'literature' and the sense of distance about space and time as 'classic' should be connected to various relationships which respond to problematic situations and the demands of learners. Based on the relationships, we can expect a rich diversity of contexts and aspects of included classical literature. In addition, an extension of the width and scope of included classical literature is anticipated. The reduction of workload, the advent of the concept of capability and the dissolution of traditional literature concepts are the changes of external environment, which is continuously requiring renewed investigation into classical literature beyond simple appropriateness.

The Restructuring of Elementary and Secondary Teacher Education System: An Analysis of Irish Case (아일랜드 교원양성체제 재구조화 사례 분석 및 시사점)

  • Kim, Ee-gyeong;Kim, Ji-hye
    • Korean Journal of Comparative Education
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    • v.26 no.4
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    • pp.81-103
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    • 2016
  • The reform of teacher policies to raise the quality of teachers has been one of the major priorities of countries around the world. Especially, the structure of elementary and secondary teacher education institutions has been the focus of international teacher policy reform agenda. Despite the problems faced by Korean teacher education system, the reform policy effort has not been actively pursued. Based on this problem recognition, this study seeks to analyze the case of Ireland to reveal the characteristics of teacher education system restructuring including background of restructuring, key strategies, and major contents. We found that the restructuring of Irish system was triggered by both domestic and international initiatives to tackle the problems of the system. The restructuring effort was led by the government and showed several distinctive features, such as reducing the number of institutions, combining elementary and secondary teacher education institutions, and strengthening research capacity of institutions. Base on the findings, a few policy recommendations were made to reignite the discussions on the reform of teacher education system in South Korea.