• Title/Summary/Keyword: physical theory

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Transmitter Beamforming and Artificial Noise with Delayed Feedback: Secrecy Rate and Power Allocation

  • Yang, Yunchuan;Wang, Wenbo;Zhao, Hui;Zhao, Long
    • Journal of Communications and Networks
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    • v.14 no.4
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    • pp.374-384
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    • 2012
  • Utilizing artificial noise (AN) is a good means to guarantee security against eavesdropping in a multi-inputmulti-output system, where the AN is designed to lie in the null space of the legitimate receiver's channel direction information (CDI). However, imperfect CDI will lead to noise leakage at the legitimate receiver and cause significant loss in the achievable secrecy rate. In this paper, we consider a delayed feedback system, and investigate the impact of delayed CDI on security by using a transmit beamforming and AN scheme. By exploiting the Gauss-Markov fading spectrum to model the feedback delay, we derive a closed-form expression of the upper bound on the secrecy rate loss, where $N_t$ = 2. For a moderate number of antennas where $N_t$ > 2, two special cases, based on the first-order statistics of the noise leakage and large number theory, are explored to approximate the respective upper bounds. In addition, to maintain a constant signal-to-interferenceplus-noise ratio degradation, we analyze the corresponding delay constraint. Furthermore, based on the obtained closed-form expression of the lower bound on the achievable secrecy rate, we investigate an optimal power allocation strategy between the information signal and the AN. The analytical and numerical results obtained based on first-order statistics can be regarded as a good approximation of the capacity that can be achieved at the legitimate receiver with a certain number of antennas, $N_t$. In addition, for a given delay, we show that optimal power allocation is not sensitive to the number of antennas in a high signal-to-noise ratio regime. The simulation results further indicate that the achievable secrecy rate with optimal power allocation can be improved significantly as compared to that with fixed power allocation. In addition, as the delay increases, the ratio of power allocated to the AN should be decreased to reduce the secrecy rate degradation.

Development of a Curriculum for Rehabilitation Nurse Specialist Program (재활 전문간호사 교육과정안 개발연구)

  • Kang, Hyun-Sook;Suh, Yeon-Ok;Lee, Myung-Hwa;Kim, Jeong-Hwa;Lim, Nan-Young;Suh, Moon-Ja;Lee, Jeong-Ja;Park, In-Joo;Cho, Bok-Hee;Kim, In-Ja;So, Hee-Young;Song, Chung-Sook;Lee, Sung-Sook;Hwang, Ok-Nam;Park, Sang-Yeun;Yoo, Yang-Sook
    • The Korean Journal of Rehabilitation Nursing
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    • v.4 no.2
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    • pp.179-186
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    • 2001
  • The purpose of this study is to develop a systematic and efficient curriculum for the rehabilitation nurse specialist program. This research was carried out as a group work of 15 experts in order to share various opinions about the curriculum, and also through literature review. Articles, curriculums of other Clinical Nurse Specialist Programs, medical laws guidelines, as well as Clinical Nurse Specialist Program from the Korean Nurses Association were reviewed, and the issue was discussed throughly via group meetings. The developed curriculum is as follows: 1. Educational philosophy lies in the fact that the rehabilitation nurses support the patients to maximize their potential and functional level, so that they could maintain healthy state and re-adapt to changed environment. Furthermore the rehabilitation nurses are disposed of arbitrary decision power under their own responsibility, thus they take charge of welfare and healthy environment of the local society through the patients(subjects) and local resources. 2. Educational goals are to train rehabilitation nurse specialist, who correspond to the social needs, so to say, those who have the knowledge and skills for nursing practice, education and research. 3. The curriculum consists of 37 credits, of which 24 credits are based on lectures and 13 credits based on clinical practice. General courses are 3 subjects (5 credits) ; nursing theory, nursing research, and laws/ethics. Mandatry courses are 8 subjects with 19 credits; advanced physical assessment, pharmacology, pathophysiology, issues in rehabilitation nursing, advanced rehabilitation nursing intervention I, advanced rehabilitation nursing intervention II, sports physiology, special rehabilitation nursing intervention. As for the clinical practice courses, assessment and evaluation for rehabilitation(64 hours), community and home based rehabilitation nursing(128 hours), hospital based rehabilitation nursing(128 hours), institution based rehabilitation nursing(96 hours) would be treated. 4. Contents of the curses were developed to correspond with the courses' objectives and specific items. 5. Evaluation would be carried out both in the lecture and in the clinical practice. The knowledge and skills of the students would be measured to ensure full validity and credibility. However this developed curriculum should be continuously modified and updated in more desirable direction.

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An Analysis on the Contents and the Trend of Nursing Research Published in Journal of Korean Academy of Adult Nursing (1989-2000) (성인간호학회지 논문(1989-2000)의 내용과 경향 분석)

  • Suh, Moon-Ja;Kim, So-Sun;Song, Mi-Soon;Yee, Myoung-Sun;Oh, Eui-Geum;Shin, Kyung-Rim;Kim, Ok-Soo;Lee, Sook-Ja;Lee, Young-Ja;Oh, Hyo-Sook;Jung, Jae-Sim;Kim, Chul-Kyu
    • Korean Journal of Adult Nursing
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    • v.13 no.4
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    • pp.571-580
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    • 2001
  • "Journal of Korean Academy of Adult Nursing" has been published since 1989 and more than 330 articles have been published up 2000. We reviewed all the articles published in this journal to analyze the contents and trend of published articles and to find out the way of improvement both in quantity and quality of studies in this area. The results are as follows; 1) Ninety percent of articles were quantitative studies. Experimental design was used in 16.1% and quasi-experimental design was adapted in 73.6% of articles. Qualitative research were 10.3% of total articles reviewed. 2) Only 5.1% of articles described theoretical framework and 73.6% of experimentally designed articles included research hypotheses. 3) Among experimental studies, only one was true experimental studie design. Eighty nine point three persent had descriptive survey method among non-experimental studies. Amog the thirty four qualitative studies, phenomenologic(73.5%), grounded theory(14.7%), and ethnographic (11.8%) design were used. 4) Most of research subject were patients and few healthy people, healthcare worker, and patient family. 5) Psychosocial data collection method which used questionnaire were 53.7% and interview, physical measurement, observation were used in 22.8%, 8.2%, 5.4% of articles respectively. 6) Total number of keywords were 692, and average number of key words per article was 2.2. Health-related keyword was the most frequently used according to four metaparadigm of nursing (human, health, nursing, and environment). Environment related keyword was rarely appeared. The number and quality of nursing research in "Journal of Korean Academy of Adult Nursing" have been improved continuously. It is difficult to find out special trend or characteristics which is unique in this journal because of relatively short history of adult nursing studies. This review study was performed to analyze adult nursing studies only in the view of quantitative aspect, but it is needed to analyse qualitatively to find philosophical or theoretical trend in nursing.

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The Research Trends in Fundamental Nursing - Based on the Analysis of Journal of Korean Academy of Fundamental Nursing - (기본간호학 연구동향 - 기본간호학회지 논문분석을 기반으로 -)

  • Jeong Ihn-Sook;Kang Kyu-Sook;Kim Kyung-Hee;Kim Keum-Soon;Kim Won-Ock;Byun Young-Soon;Sohng Kyeong-Yae;Son Yeong-Hee;Yang Sun-Hee;Jo Hyun-Sook
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.8 no.2
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    • pp.132-146
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    • 2001
  • Purpose: This study was to analyze the trends and content of all the research (171 research papers) published in the Journal of Fundamentals of Nursing from 1994, when it began to 2000 using an objective tool developed by the researches, and to identify the direction for the future research in Fundamentals of Nursing. Method: Research published in the Journal of Fundamentals of Nursing from 1994 were reviewed. Result: Most of research (94.2%) was non-degree based and funded research was very limited. The average number of researchers per research study was 2.2 and collaborative research has been gradually increasing. The total number of key words was 331 and the average was 2.6 per research. The major key words were not different from other nursing departments and included home care nursing (10 times), health promotion (8 times), self-care (7 times). self-efficacy (7 times), and homo-dialysis (6 times). Eighty seven percent of the research was quantitative research. and there were very few qualitative studies. Considering theory level, it was found that 40% were factor related research For study design, non-experimental studies were most frequent (66%), and the rate, especially of surveys, has remarkably decreased. Selection of subjects by convenience sampling, was most frequent and there were very few studies that provided the rationale for the calculation of sample size. The major subjects of study were patients (44.8%) with various diagnoses. The subjects usually gave oral consent to take part in that study. Giving information (46.9%) and exercise (26.5%) were common nursing interventions, and physiological indices (16.5%). vital signs (10.3%), physical functioning (8.2%), level of knowledge/skill (7.2%) and level of activity (6.2%) were frequently measured as outcome. Variables questionnaires were the major approach used to collect data, and 57.8% of the research provided the Cronbach alpha to guarantee internal consistency of study instruments. Data were analyzed with computerized statistical packages using, ANOVA (42.0%), T test(39.5%), and chi-square test. For the last seven years, nursing research in Fundamentals of Nursing has gradually improved in both quantify and quality. Conclusion: It was difficult to find any uniqueness or difference compared to other departments of nursing. In fact, because the history of the Journal of Fundamentals of Nursing is rather short, we can expect that there will be further improvement in qualify and content in the future.

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The Effect of Sensory Integration Intervention Program on Body-scheme and Praxis Ability in Children With Developmental Disability (감각통합치료프로그램이 발달장애아의 신체도식과 실행능력에 미치는 영향)

  • Kim, Hyun-Ho;Yoo, Byung-Kook;Jang, Yong-Su
    • The Journal of Korean Academy of Sensory Integration
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    • v.7 no.1
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    • pp.47-57
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    • 2009
  • Objective : Purpose of this study is to study how Sensory Integration (SI) Intervention Program affect body-scheme and praxis ability of children with Developmental Disability (DD). Method : The SI intervention was programmed based on the theory of SI by Jean Ayres. Thirty children with DD underwent the SI program for six weeks. The effect of the SI intervention was evaluated in terms of body-scheme and praxis ability. Assessments used in this study are One-Point Imitation Test (OPIT) and 6 Body Puzzle Test (6BPT) for body-scheme; Praxis Test Sheet (PTS) for linguistic order, oral motor control, sequential praxis and Sensory Integration and Praxis Tests (SIPT) for postural praxis. Data of this study was analyzed by the paired t-test to compare before- and after the SI intervention. Results : Results of this study are (1) in the OPIT, there is significant difference on body-scheme ability (p<0.01); (2) in the PTS, there is significant difference on all three items (p<0.01); and (3) in the SIPT, there is significant difference on sensory integration and praxis function. Conclusions : From the results, it is concluded that sensory integration intervention is effective on body-scheme and praxis functions for children with developmental disability.

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A Study on the Priority Analysis in Stakeholers of Information Systems Audit using Fussy-ANP Method (Fuzzy ANP 기법을 이용한 정보시스템 감리 이해당사자별 우선순위 분석에 관한 연구)

  • Kyung, Tae-Won;Kim, Sang-Kuk
    • Information Systems Review
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    • v.11 no.1
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    • pp.85-106
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    • 2009
  • Current trend of audit is to check the physical aspects of developed information system, such as checking the budget constraints, time constraints or functional fluency etc. However, ultimate goal of information system is to help the organization to achieve the competency over their competitors. Also, there are three different interest groups in system auditing, like audit requesting group, audited group and audit group, who may have different points of interests in auditing. Current auditing process, however, ignores this point, and so does not check the differences between three groups. This study tries to develop new auditing method to cure these two problems. Contributions of this study may be summarized as follows. First, Redefine Information Systems Audit from a service point of view. Second, Divide the audit related person into three groups, and their different needs toward the information system was analyzed. Third, Analyze and compare the main interests of three groups, and weights of each groups to each indexes were calculated. Fourth, Fuzzy theory was applied to quantify the qualitative answers, which may minimize the ambiguity of questionnaire replies.

Conceptual Metaphor based on Embodied Cognition (체현 인지에 기반한 개념 메타포에 관한 연구)

  • Kim, Hyung-Woo
    • Journal of Korea Multimedia Society
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    • v.16 no.7
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    • pp.888-896
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    • 2013
  • The existing interface study has been focused on rhetorical metaphor based on a cognitive viewpoint in traditional objectivism. But the existing study viewpoint about the interface shows logical limitation by the changes in media environment. This study suggests conceptual metaphor based on embodied cognition for an alternative to solve the limitation, and research logical suitability of the existing interface environment. The result of this study is as follow; The first, the embodied cognitive viewpoint provides the interface as a space for holistic recognition communication, and the conceptual metaphor based on embodied cognition provides a well-structured metaphor logic and is a suitable metaphor to explain complicated metaphor structure. The second, the container image schema provides concrete and detailed metaphor structure than previous metaphor when it comes to explaining desktop metaphor by offering subsidiary image schema from 'IN-OUT-BOUNDARY' image schema. The third, path image schema is possible to make a concrete logic and works off the laxity and confusion of logical structure in existing metaphor by offering subsidiary image schema from 'SOURCE-PATH-GOAL' image schema. The conceptual metaphor based on embodied cognition is expected to be a basic theory to explain interfaces for various media environment by thinking of human physical experience as container and path image schema.

Representation of Wilderness in Western Films: An Aesthetic Interpretation (서부 영화에서 황야의 재현에 대한 미학적 해석)

  • Lee, Myeong-Jun;Pae, Jeong-Hann
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.2
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    • pp.1-10
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    • 2013
  • This paper aims to make an aesthetic inquiry into representing modes of wilderness in western films. The western film was the first genre in earnest about natural landscape, covering vast areas of America from the East to the West. It adopted representative modes suited to physical characteristics of landscapes which produced aesthetic characteristics. In western films, wilderness was represented at a distance from the camera lens as a setting and an object of contemplation. In eastern forest landscapes, western films adopted the visual model of Hudson River School's landscape painting which expressed the transcendental sublime. The western semiarid region reproduced the warrior's gaze shot from a high angle, and, in this visual mode, wilderness was expressed as a demonic landscape derived from Burke's definition of the sublime. On one hand, the western desert was represented as a place of hardship shot at a low angle which expressed the vastness, unevenness and limitlessness of the desert owing to the absence of horizon. On the other hand, the mesas of Monument Valley have sublime characteristics of size and time. In western films, they play the role of an emblem by rising from the limitless desert on the horizon. The prospect-refuge relationship, the desire to see without being seen, is discovered in the representative mode of wilderness in western films. In this context, this study hopes to discover the archetype of landscape representation.

A Policy of Page Management Using Double Cache for NAND Flash Memory File System (NAND 플래시 메모리 파일 시스템을 위한 더블 캐시를 활용한 페이지 관리 정책)

  • Park, Myung-Kyu;Kim, Sung-Jo
    • Journal of KIISE:Computer Systems and Theory
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    • v.36 no.5
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    • pp.412-421
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    • 2009
  • Due to the physical characteristics of NAND flash memory, overwrite operations are not permitted at the same location, and therefore erase operations are required prior to rewriting. These extra operations cause performance degradation of NAND flash memory file system. Since it also has an upper limit to the number of erase operations for a specific location, frequent erases should reduce the lifetime of NAND flash memory. These problems can be resolved by delaying write operations in order to improve I/O performance: however, it will lower the cache hit ratio. This paper proposes a policy of page management using double cache for NAND flash memory file system. Double cache consists of Real cache and Ghost cache to analyze page reference patterns. This policy attempts to delay write operations in Ghost cache to maintain the hit ratio in Real cache. It can also improve write performance by reducing the search time for dirty pages, since Ghost cache consists of Dirty and Clean list. We find that the hit ratio and I/O performance of our policy are improved by 20.57% and 20.59% in average, respectively, when comparing them with the existing policies. The number of write operations is also reduced by 30.75% in average, compared with of the existing policies.

Application of Flood Discharge for Gumgang Watershed Using GIS-based K-DRUM (GIS기반 K-DRUM을 이용한 금강권 대유역 홍수유출 적용)

  • Park, Jin-Hyeog;Hur, Young-Teck
    • Journal of Korean Society for Geospatial Information Science
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    • v.18 no.1
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    • pp.11-20
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    • 2010
  • The distributed rainfall-runoff model which is developed in the country requires a lot of time and effort to generate input data. Also, it takes a lot of time to calculate discharge by numerical analysis based on kinematic wave theory in runoff process. Therefore, most river basins using the distributed model are of limited scale, such as small river basins. However, recently, the necessity of integrated watershed management has been increasing due to change of watershed management concept and discharge calculation of whole river basin, including upstream and downstream of dam. Thus, in this study, the feasibility of the GIS based physical distributed rainfall-runoff model, K-DRUM(K-water hydrologic & hydraulic Distributed RUnoff Model) which has been developed by own technology was reviewed in the flood discharge process for the Geum River basin, including Yongdam and Daecheong Dam Watersheds. GIS hydrological parameters were extracted from basic GIS data such as DEM, land cover and soil map, and used as input data of the model. Problems in running time and inaccuracy setting using the existing trial and error method were solved by applying an auto calibration method in setting initial soil moisture conditions. The accuracy of discharge analysis for application of the method was evaluated using VER, QER and Total Error in case of the typhoon 'Ewiniar' event. and the calculation results shows a good agreement with observed data.