• Title/Summary/Keyword: Air Force

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An Research Into The Reactive Safety Action Program for Promoting Aviation Safety Culture

  • Kim, Dae Ho
    • Journal of the Ergonomics Society of Korea
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    • v.35 no.3
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    • pp.165-173
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    • 2016
  • Objective: The objective of this research is to inquire about safety information from the standpoint of its usefulness to suggest the significance of the Reactive Safety Action Program, which serves to promote aviation safety culture. Background: Safety information plays an important role in operating safety programs. Each organization learns lessons from safety information collected from aviation accidents and incidents. When an accident occurs, it is only through safety investigation and a close inquiry on the cause that we can come up with an appropriate countermeasure which would contribute to preventing the recurrence of the same or similar accident. However, the usefulness of safety information produced from unsatisfactory safety investigation is insufficient. Method: This research analyzed the characteristics of aviation accidents, the differences between safety investigations and legal accident investigations in systematic and operative perspectives, and safety culture as a measure to activate reporting systems (compulsory/voluntary). Results: This research defined the investigation scope and processes of safety investigations and legal accident investigations. It also suggested factors such as just culture based on trust, non-punitiveness, confidentiality, the participation of the entire staff through the use of inclusive reporting base, ensuring the independence of the operating organization as a way to promote safety through reporting systems. Conclusion: The organization's effort is the important aspect in obtaining exact and accurate safety information from accidents/incidents. The separate running of SIB (Safety Investigation Board) and AIB (Accident Investigation Board), the systematization of safety information reporting system, and prescribing (legislating) the composition of related organizations are some representative programs. Application: This research inquired experiences that contributed in promoting aviation safety culture in a reactive perspective, and will serve a role in spreading safety culture by enabling the use of application experiences of the aviation field in other domains.

Reduction of Electromagnetic Field from Wireless Power Transfer Using a Series-Parallel Resonance Circuit Topology

  • Kim, Jong-Hoon;Kim, Hong-Seok;Kim, In-Myoung;Kim, Young-Il;Ahn, Seung-Young;Kim, Ji-Seong;Kim, Joung-Ho
    • Journal of electromagnetic engineering and science
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    • v.11 no.3
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    • pp.166-173
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    • 2011
  • In this paper, we implemented and analyzed a wireless power transfer (WPT) system with a CSPR topology. CSPR refers to constant current source, series resonance circuit topology of a transmitting coil, parallel resonance circuit topology of a receiving coil, and pure resistive loading. The transmitting coil is coupled by a magnetic field to the receiving coil without wire. Although the electromotive force (emf) is small (about 4.5V), the voltage on load resistor is 148V, because a parallel resonance scheme was adopted for the receiving coil. The implemented WPT system is designed to be able to transfer up to 1 kW power and can operate a LED TV. Before the implementation, the EMF reduction mechanism based on the use of ferrite and a metal shield box was confirmed by an EM simulation and we found that the EMF can be suppressed dramatically by using this shield. The operating frequency of the implemented WPT system is 30.7kHz and the air gap between two coils is 150mm. The power transferred to the load resistor is 147W and the real power transfer efficiency is 66.4 %.

A Vision for Nursing Education Reform in Korea (한국 간호교육에 대한 개혁 전망)

  • 김모임
    • Journal of Korean Academy of Nursing
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    • v.24 no.2
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    • pp.313-318
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    • 1994
  • To build a suitable National Health Care System for the coming 21s1 century, Nursing must also be renewed. The future Korea will be united and the majority of its population will raidly consist of the aged. Economically standing on the same level with developed countries the growth of scientific technologies will foster communications, firing astounding changes in the medical field. While the overall life style pattern of Koereans not to mention the structure of diseases undergo change, the possibility that the reckless induction of high-tech health care may only cause medical fees to eascafate. It can전so be expected that the health care system will evolve towards the consumers. Nursing in the 21s1 century will be of two scenarios according to WHO, which presents the role of the nurse. The first scenario is that "a gen-eric health care work force" namely a "care giver" will replace all other health professions. If Nursing does not become the compatent profession fitting to this purpose it will eventually dei out. The second scenario is that nurses who are educated in a well grounded and extensive general background and have command of a specialized area will undertake services varying from health pro-motion to treatment and rehabilitation both direct and indirectly, while supervising other personnel. The nurse here would become the "care giver". To become the necessary health care profession in the 21s1 century, nurses should be provided with more educational opportunities, variating in its con-tents, course, and system, enabling them to grow. Clair Faign points out that the minimal educational entry for the nursing profession is a 4 year undergraduate education in this aspect, now in the time to set the future of Nursing into the course of the first scenario. A new educational system stipulating a baccalaureate nursing degree is in urgent need, and aside from govermental actions nurse themseives should formaily officiallze this process, striving for quality assurance. While considering 6 years nursing education programs, multifarious degree courses for existing 3 years educated nurse should be provided Junior nursing schools must devise measures to grow into baccalaucate institutions, also. Among the existing courses, the Self Study Degree Program should be converted into RN, BSN courese provided by universities, and clinical training for the University on the Air must be supplimented, The possibility of establishing nursing courses into commercial high school programs only jeopardizes the development of the nursing profession.

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A Study on the Unsteady Flow Characteristics of a Delta Wing by 3-D Stereo PIV (3-D Stereo PIV에 의한 비정상 델타윙 유동특성에 대한 연구)

  • Kim, Beom-Seok;Lee, Hyun;Kim, Jeong-Hwan;Lee, Young-Ho
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.1672-1677
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    • 2004
  • Leading edge extension(LEX) in a highly swept shape applied to a delta wing features the modem air-fighters. The LEX vortices generated upon the upper surface of the wing at high angle of attack enhance the lift force of the delta wing by way of increased negative suction pressure over the surfaces. The present 3-D stereo PIV includes the Identification of 2-D cross-correlation equation, stereo matching of 2-D velocity vectors of two cameras, accurate calculation of 3-D velocity vectors by homogeneous coordinate system, removal of error vectors by a statistical method followed by a continuity equation criterion and so on. A delta wing model with or without LEX was immersed in a circulating water channel. Two high-resolution, high-speed digital cameras($1280pixel{\times}1024pixel$) were used to allow the time-resolved animation work. The present dynamic stereo PIV represents the complicated vortex behavior, especially, in terms of time-dependent characteristics of the vortices at given measuring sections. Quantities such as three velocity vector components, vorticity and other flow information can be easily visualized via the 3D time-resolved post-processing to make the easy understanding of the LEX effect or vortex emerging and collapse which are important phenomena occurring in the field of delta wing aerodynamics.

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A Study of Crack Propagation and Fatigue Life Prediction on Welded Joints of Ship Structure (II) (선체 용접부의 균열진전 및 피로수명예측에 관한 연구(II))

  • Kim, Kyung-Su;Shim, Chun-Sik;Kwon, Young-Bin;Ko, Hee-Seung;Ki, Hyeok-Geun;Viswanathan, K.K.
    • Journal of the Society of Naval Architects of Korea
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    • v.45 no.6
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    • pp.679-687
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    • 2008
  • The fatigue life of ship structure under cyclic loading condition is made up of crack initiation and propagation stages. For a welding member in ship structure, the fatigue crack propagation life is more important than the fatigue crack initiation life. To calculate precisely the fatigue crack propagation life at the critical welding location, the knowledge of the residual stress sensitivity on the fatigue strength is necessary. In this study, thermo elastic-plastic analysis was conducted in order to examine the effect of residual stress on the fatigue crack propagation life. Also the fatigue crack propagation lives considering residual stress were calculated using fatigue crack growth code, AFGROW, on the basis of fracture mechanics. AFGROW is widely used for fatigue crack growth predictions under constant and variable amplitude loading. The reliability of AFGROW on the fatigue of ship structure was confirmed by the comparison of the estimated results with the fatigue propagation test results.

Analysis of A New Crossbar Embedded Structure for Improved Attenuation Characteristics on the Various Lossy Media (다양한 손실매질내의 손실특성 개선을 위한 새로운 크로스바 구조의 해석)

  • Kim, Yoon-Suk
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.43 no.12 s.354
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    • pp.83-88
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    • 2006
  • In this paper, we propose a new cross bar embedded structure for improvement of attenuation characteristics along the different lossy media. A general characterization procedure based on the extraction of the characteristic impedance and propagation constant for analyzing a single MIS(Metal-Insulator-Semiconductor) transmission line used and an analysis for a new substrate shielding MIS structure consisting of grounded crossbars at the interface between Si and Sio2 layer using the Finite-Difference Time-Domain(FDTD) technique is used. In order to reduce the substrate effects on the transmission line characteristics, a shielding structure consisting of grounded cross bar lines over time-domain signal has been examined. The extracted, distributed frequency-dependent transmission line parameters as well as the line voltages and currents, and also corresponding equivalent circuit parameters have been examined as function of frequency. It is shown that the quality factor of the transmission line can be improved without significant changes in the characteristic impedance and effective dielectric constant.

Authors Under the Service of the Army in the Korean War (한국전쟁기 육군종군작가단의 작품 활동)

  • 신영덕
    • Lingua Humanitatis
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    • v.1 no.2
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    • pp.197-217
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    • 2001
  • The literary products of Authors Under the Service of the Army during the Korean War have been neglected on the whole because of the perception that they were little more than war propaganda. The majority of the works (poetry, serial novels, and short stories) Published by these authors in various Army publications such as Junsunmunhak (Literature of the War Front) and Comet, as well as in regular literary periodicals, supports this perception. Most of these works convey simplistic emotions and stereotypes that project untroubled patriotism and strongly antipathetic sentiments against to the Communist North. The appointed leader of this group, Dock-Kyun Choi regarded the pen as another form of weapon to be used against the Communists in the North, and did not shy away from describing in graphic details the atrocities committed by his enemies. But what truly deserves our attention is the fact that many of the same authors who wrote highly propagandistic works also wrote works that can only be described as antiwar. In these works are depicted as faithfully as possible the human sufferings of the war. These works resist and even question the very ideologies that have brought about the conflict, focusing instead on the dark side of the war -the horrifying deaths, the separation of families, and the displacement of people from their homes, How we are to interpret this ambivalence in many of these authors is a task that remains to be carried out. We must approach these works with more seriousness and begin by comparing them with similar products from authors under the service of the Navy and the Air Force during the Korean War.

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A Fundamental Study of Structure-Property Relationships in $Eu^{3+}$ Luminescence ($Eu^{3+}$ 이온의 발광성에 대한 구조와 성질의 기본적인 연구)

  • Chang, Ki-Seog
    • Korean Journal of Crystallography
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    • v.13 no.1
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    • pp.25-30
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    • 2002
  • The M/sub 1-x/Na/sub 2x/Al₂(BO₃)₂O (M = Ca and Sr) solid solution systems have been shown interstitial solid solutions and continuous substitutional solid solutions. The symmetry around the Eu site of yEu/sup 3+/ : M/sub 1-x/Na/sub 2x/Al/sub 2-y/Mg/sub /(BO₃)₂O (M = Ca and Sr) changes the intensities and the chromaticities of transitions. The Eu/sup 3+/ion can be very bright and efficient and have the desired emission wave-length depending on the site symmetry of the Eu/sup 3+/ion site. As the amount of Na in the Eu/sup 3+/ion doped Ca/sub 1-x/Na/sub 2x/Al₂(BO₃)₂O system increases, the Eu site symmetry is going to be a noncentrosymmetric site. With increasing x, the decreased intensity in the /sup 5/D/sub 0/→/sup 7/F₁(590 nm) transition relates to the low symmetry of the Eus/up 3+/-doped Ca/sub 1-x/Na/sub 2x/Al₂(BO₃)₂O system, because of the Ca-centered octahedron in the CaAl₂(BO₃)₂O compound. The SrAl₂(BO₃)₂O compound also provides an improved chromaticity due to the lower site symmetry of Eu/sup 3+/ion.

Sea Breeze Criterion and the Climatological Characteristics of the Short-time Sea Breeze in Gangneung Coastal Area (강릉 연안지역 해풍의 선정기준과 단 시간 해풍의 기후학적 특성)

  • Park, Jae-Hong;Jung, Woo-Sik;Leem, Heon-Ho;Lee, Hwa-Woon
    • Journal of the Korean earth science society
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    • v.23 no.5
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    • pp.436-441
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    • 2002
  • This study is concerned with the sea breeze criterion and climatological characteristics of the short-time sea breeze in the Gangneung coastal area. The sea breeze criteria in this area are listed here. First, the fact of the sea breeze blowing was considered to be a change of wind direction from land to sea and vice versa without terrain effect like easterly wind. Second, the sea breeze of which continuous time 1-hour or 2-hour was selected. Then the climatological characteristics of the short-time sea breeze were analyzed using the meterological data from a 10-year(1988${\sim}$1997) period. The climatological characteristics which were analyzed for the short-time sea breeze consist of the frequency, onset time, wind direction speed and temperature. Finally, this study will be helpful in meteorological application through the climatological characteristics of sea breeze along the east coast as well as Gangneung Airport.

PERFORMANCE AND DESIGN OF A SINGLE-PHASE LINEAR SYNCHRONOUS GENERATOR USING FINITE ELEMENT METHOD

  • Eid, Ahmad M.;Kim, Sung-Jun;Kang, Ju-Sung;Lee, Hyun-Woo;Nakaoka, Mutsuo
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2005.11a
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    • pp.95-99
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    • 2005
  • This paper presents a general proposal to design and calculate the performance of a tubular permanent magnet linear generator treated here on the basis of the Finite Element Method. Optimizing the linear generator dimensions reduces the cogging force, which occurs due to the interaction between stator teeth and the permanent magnets. The generated AC voltage is analyzed and evaluated for both no load and load cases to take the armature reaction effects on the air gap flux density. A repetitive routine is followed to calculate the output AC voltage from the change of flux and the speed of the single-phase linear generator. The AC output voltage is calculated for different resistive loads, and hence, the linear generator load characteristic is obtained. The designed linear generator is capable to generate an output power of 5.3kW with AC output voltage of 222V with an efficiency of 96.8% at full load of 23.8A. The full load current is chosen based on the thermal properties of the coil wire insulations.

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