• Structural Engineering and Mechanics
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• 제30권6호
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• pp.679-698
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• 2008

On marine vessels, delicate instruments such as navigation radars are normally mounted on ship masts. However the vibrations at the top of mast where the radar is mounted often cause serious deterioration in radar-tracking resolution. The most serious problem is caused by the rotational vibrations at the top of mast that may be due to wind loading, inertial loading from ship rolling and base excitations induced by the running propeller. This paper presents a method of semi-active vibration control using magneto-rheological (MR) dampers to reduce the rotational vibration of the mast. In the study, the classical optimal control algorithm, the independent modal space control algorithm and the double input - single output fuzzy control algorithm are employed for the vibration control. As the phenomenological model of an MR damper is highly nonlinear, which is difficult to analyse, a back- propagation neural network is trained to emulate the inverse dynamic characteristics of the MR damper in the analysis. The trained neural network gives the required voltage for each MR damper based on the displacement, velocity and control force of the MR damper quickly. Numerical simulations show that the proposed control methods can effectively suppress the rotational vibrations at the top of mast.

• 기본간호학회지
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• 제23권2호
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• pp.172-183
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• 2016

Purpose: The purpose of this study was to explore the subjective experience of life-sustaining treatment care among nurses in intensive care units. Method: A phenomenology was used for the study. Data were collected from October to December, 2015 using open-ended questions during in-depth interviews. Participants were nurses working in intensive care units and were contacted through purposive techniques. Eight nurses participated in this study. Results: Four categories emerged from the analysis using Colaizzi's method: (a) difficulties due to life-sustaining treatment care, (b) dilemma of extension or cessation of life-sustaining treatment, (c) repressed feelings and emotional exhaustion, and (d) forming values for life-sustaining treatment from nursing experience. Conclusion: Provision of clearer guidelines on life-sustaining treatment which reflect a family-oriented culture is important for nurses in ICU and will promote nurses involvement in the decision-making process of life-sustaining treatment of patients.

• 한국간호교육학회지
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• 제19권3호
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• pp.351-361
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• 2013

Purpose: This study aimed to understand and explain the essences and structures of the experience of Korean nursing students' college life who have defected from North Korea. Korea. Methods: The data were collected in 2012 through individual in-depth interviews using open-ended questions. A total of 6 nursing students who have escaped from North Korea participated in the study. Each interview lasted about 2 hours. Verbatim transcripts were analyzed using Phenomenological analysis. Results: Four theme clusters emerged by the analysis using Collaizzi's method: a dream of passing, the stern realities of life, out of the frying pan into the fire, and passion for my dream. These theme clusters illustrate that although most participants faced very strange and strenuous situations in most aspects of college life, each of them had hope to be an a good nurse in the future. The essence of the experience of participants was "living as a star in the black night". Conclusion: This study provides deep understanding of college life of nursing students who defected from North Korea. Based on the results of the study, the Korean government, society, and college should support refugees in order to help settle well in Korean society.

• 천문학회지
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• 제46권1호
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• pp.49-63
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• 2013

Nonthermal radiation from supernova remnants (SNRs) provides observational evidence and constraints on the diffusive shock acceleration (DSA) hypothesis for the origins of Galactic cosmic rays (CRs). Recently it has been recognized that a variety of plasma wave-particle interactions operate at astrophysical shocks and the detailed outcomes of DSA are governed by their complex and nonlinear interrelationships. Here we calculate the energy spectra of CR protons and electrons accelerated at Type Ia SNRs, using time-dependent, DSA simulations with phenomenological models for magnetic field amplification due to CR streaming instabilities, Alf$\acute{e}$enic drift, and free escape boundary. We show that, if scattering centers drift with the Alf$\acute{e}$en speed in the amplified magnetic fields, the CR energy spectrum is steepened and the acceleration efficiency is significantly reduced at strong CR modified SNR shocks. Even with fast Afv$\acute{e}$nic drift, DSA can still be efficient enough to develop a substantial shock precursor due to CR pressure feedback and convert about 20-30% of the SN explosion energy into CRs. Since the high energy end of the CR proton spectrum is composed of the particles that are injected in the early stages, in order to predict nonthermal emissions, especially in X-ray and ${\gamma}-ray$ bands, it is important to follow the time dependent evolution of the shock dynamics, CR injection process, magnetic field amplification, and particle escape. Thus it is crucial to understand the details of these plasma interactions associated with collisionless shocks in successful modeling of nonlinear DSA.

• 간호행정학회지
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• 제20권1호
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• pp.82-94
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• 2014

Purpose: This study was conducted to define the experiences of nursing activities in Gwangju area during the May 18 (5 18) Democratic Uprising over 30 years ago. Methods: Data were collected in 2010 and 2011 through individual in-depth interviews. Ten nurses who worked in general hospitals in the Gwangju area during the 5 18 Democratic Uprising were interviewed using open-ended questions. Each interview lasted about 2~3 hours. Verbatim transcripts were analyzed using Van Kaam's method of phenomenological analysis. Results: Four categories emerged from the analysis: anxiety about the incident which was experienced for the first time; progress of the 5 18 events and relationship to participants; changes in nursing environment; retrospection and wishes related to the 5 18 incident. Conclusion: This oral history study revealed more clearly of the experiences of nursing activities in the Gwangju area during the 5 18 Democratic Uprising. The data may provide a basis for writing history nursing in the community, and can be a basis for guidelines covering nursing care in crisis.

• 한국도서관정보학회지
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• 제44권1호
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• pp.177-199
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• 2013

본 연구는 질적 다방법을 적용하여 복합 현상인 사서의 직업 사회화 경험의 실체이론을 구성하였다. 일련의 3개 질적 선행연구의 총참여자는 이론적 표집에 의한 42명의 현직 사서(사서교사)들이다. 질적 다방법 접근의 최종 통합방법으로서 근거이론 방법을 적용하여 3개의 선행연구 결과 및 심층면담자료의 최종분석과 비교, 재검토, 통합을 하였다. 사서의 직업사회화 경험의 전체과정을 이끌고 통합하는 핵심범주는 사서가 대중들로 부터 신뢰와 존중, 사회적 영향력을 추구하는 과정인 '사회적 인정 추구하기'로 도출하였다. 사서의 직업사회화의 '사회적 인정추구하기'의 경험 유형은 '사서직과 자아 일치형'과 '자아 불일치형'으로 구분되며, 여기에는 '신념형', '성공지향형', '업무 책임감형', '열악함 매몰형', '개인자존감형', '회의형'으로 도출되었다. 각 유형별 직업사회화 특성과 지원방안을 제시하였다.

• 간호행정학회지
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• 제18권3호
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• pp.301-309
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• 2012

Purpose: This study was done to investigate changes in image of nursing in first year students of nursing after courses on history & philosophy of nursing. Methods: Participants were 100 first year students at a nursing college located in K city. The students were asked to submit a written answer to an open-ended question. Data were collected in March, 2011, before the students started nursing courses, and again in June, 2011, after they had finished one semester of nursing courses. Data were analyzed using Van Kaam's phenomenological method. Results: Before the nursing courses, students regarded nursing as caring for patients comfortably with warmth and kindness, helping patients with self-sacrificing spirit and service, and being tough and overwhelming to do. After finishing one semester of nursing courses, they regarded nursing as a profession that requires motherly care, love and devotion, and as meaningful and beautiful to do. Conclusions: After finishing one semester of nursing courses, the images of nursing held by the students changed from a traditional perspective emphasizing the emotional and negative aspects to one focusing more on the professional and positive aspects. It is essential to establish healthy and positive images of nursing among students through the nursing curriculum.

• 융합정보논문지
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• 제10권9호
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• pp.35-42
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• 2020

본 연구는 임상 간호 현장에서 종합병원 신규 간호사의 태움 경험을 이해하고 이를 토대로 우리나라의 간호 환경 개선 및 태움에 대한 대책 마련을 위한 조직적 차원에서의 제도적 장치를 마련하는데 기초 자료를 제공하고자 시도되었다. 본 연구는 현상학적인 방법을 사용하였고 자료 수집은 심층 면담으로 진행하였다. 자료 수집 기간은 2019년 9월부터 12월까지였으며 연구 참여자는 임상 간호 현장에서 태움을 경험한 신규 간호사 7명이었다. 연구 결과 신규 간호사의 태움 경험은 3개의 주제와 7개의 범주로 도출되었다. 3개의 주제는 '태움으로부터 의연해 지기 위하여 도피처를 찾아해맴', ' 모든 사람들로부터 갑질을 당함', ' 정신적, 신체적으로 병들어감'이었다. 본 연구를 통하여 종합병원 신규 간호사들의 태움에 영향을 주는 요인을 규명하고 실무 현장에서 이들이 전문직 간호사로 성장할 수 있는 방법에 대한 모색이 필요하다 하겠다.

• 대한간호학회지
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• 제28권2호
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• pp.291-302
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• 1998

The purpose of this phenomenological study was to understand and describe the essence and the structure of lived experience of people with kidney transplantation. Initially, nine individual interviews were conducted to gather data regarding their subjective experiences. And two focus group interviews were utilized to validate or discard the themes that were emerged from the analysis using Colaizzi's method. Among 17 participants, 13 had living related kidney donations, one living unrelated, and the remaining two cadavor donations. About 130 significant statements were extracted and these were clustered into 11 themes. All participants felt anxiety and fear toward the rejection of transplantation and the complication of immunosuppressive drugs. Although they were initially satisfied with their life after kidney transplantation, most of them lost a self-confidence and experienced loneliness, depression, and despair. Most of the participants also felt guilty for not being able to accomplish their appropriate roles in the family, They also had financial difficulties and social restrictions. However, they overcame these psychosocial distress by exercising, working and sharing love with others. They also could overcome it by living a religious life and by working to help others with kidney transplantations. Most of them felt gratitude toward the donor and did not have a psychological rejection toward the kidney transplanted. The results of the study might help nurses who work with people with kidney transplantations in establishing and implementing an effective nursing intervention by understanding their lived experience.

• 대한간호학회지
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• 제36권7호
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• pp.1215-1223
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• 2006

Purpose: This study was done to understand elderly women within a community who have used lots of drugs. Method: Data was collected through in-depth interviews with four elderly women from April 2001 to February 2002. Data was analyzed by Giorgi's phenomenological method(2000). Results: The components in common with drug usage of elderly women were as follows: 'Awareness of the limitation of physical strength and uncertainty of life', 'Dread of a crisis situation occurring', 'Attachment and dependency on drugs', 'Expectation of a comfortable life and death', 'Prevention of family burden', and 'Pursuit of psychological comfort'. The general structure of experiences was as follows: causal factors were 'Awareness of uncertainty and limitation', 'dread of a crisis situation occurring' the results factor was 'Attachment and dependency on drugs' and the facilitating factors were 'Expectation of a comfortable life and death', 'Prevention of family burden', and 'Pursuit of psychological comfort'. The causal relation was cyclic. This structure showed a realistic adaptation pattern. Conclusion: This study contributed to provide fundamental data for nursing interventions for health promotion and promoting quality of life in elderly women by increasing understanding of the experiences of drugs use.