• 한국전기전자재료학회논문지
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• 제13권4호
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• pp.326-331
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• 2000

We have fabricated the field emitter arrays coated with diamond-like carbon (DLC) films that improved the field emission characteristics. The nitrogen doped DLC films are prepared by the filtered cathodic vacuum are (FCVA) tehnique. The activation energy of the nitrogen doped DLC films are derived from electrical conductivity measurements. The silicon field emission arrays (FEAs) were prepared by the VLSI technique. The turn-on field was rapidly decreasing and the emission current was remarkably increasing the DLC-coated FEAs than the non-coated silicon FEAs. In the nitrogen doped FEAs, the turn-on field decreased and the emission current increased with increasing the nitrogen found out the field emission current and the work function of the DLC-coated FEAs was remarkably decreased than that of the non-coated silicon FEAs. As nitrogen doping concentrations are increased the work function of FEAs is decreased and the field emission properties are improved in nitrogen doped DLC-coated FEAs. This phenomenon in due the fact that the Fermi energy level moves to the conduction band by increasing nitrogen doping concentration.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.1049-1052
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• 2007

Extremely sharp and uniform Transfer Mold FEAs with thin film low work function TiN emitter material have been fabricated by controlling the thickness of the coated emitter materials to realize high efficient, high reliable and low-cost vacuum nanoelectronic devices..Their tip radii are 8.3-13.8 nm. Turn-on electric fields of the Ni FEAs and TiN-FEAs resulted in the low electric field values of $31.6\;V/{\mu}m$ and $44.2V/{\mu}m$,respectively, at the short emitter/anode distance: less than $30\;{\mu}m$, which are lower than those of conventional FE As such as Spindt type FEAs and carbon nan otube FEAs The Transfer Metal Mold fabrication method is one of the best methods of changing emit ter materials with sharp and uniform emit ter shapes.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1997년도 한국재료학회 추계학술발표회
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• pp.155-155
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• 1997

• International Journal of Naval Architecture and Ocean Engineering
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• 제9권6호
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• pp.705-719
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• 2017

Progressive Collapse Method (PCM) has been broadly applied to predict moment-carrying capacity of a hull girder, however accuracy of PCM has not been much studied. Accuracy of PCM is known to be dependent on how Load-Shortening and -Elongation (LSE) curve of a structural units are well predicted. This paper presents a new procedure to determine LSE datum based on box girder Finite Element Analyses (FEAs) instead of using finite element model of stiffened panels. To verify reliability of FEA results, the simple box girder collapse test results are compared with FEA results of same box girders. It reveals one frame-based box girder model is sufficiently accurate in terms of ultimate strengths of the box girders. After extracting LSE data from the box girders, PCM-based moment-carrying capacities are compared with those from FEAs of the box girders. PCM results are found to be equivalent to FEAs in terms of moment-carrying capacity if accurate LSE data are secured. The new procedure is applied to well-known 1/3 scaled frigate full section. Very excellent moment-carrying capacity of frigate hull section is obtained from PCM with LSE data from box girder FEAs.

• Journal of Acupuncture Research
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• 제24권5호
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• pp.151-170
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• 2007

Backgraounds : Recent studies provide the evidences that the efficacy of acupuncture may be no better than placebo or inconclusive. These results are very different from those of the actual clinical situations in many acupuncture medical institutions. Objectives : The present study was designed to evaluate the influencing factors which affect the efficacy of acupuncture scale(FEAS) as the methodological assessment tool of acupuncture for examining acupuncture interventions and to demonstrate the importance of it in randomized controlled trials of acupuncture. Data sources : Electronic data were retrieved from NDSL, Pubmed, sciencedirect, LWW, OVID, Black-Well Synergy, Wiley Interscience, EBSCO HOST, springer, PML, and Kluwer. No electronic data were collected from MEDLIS and MEDLAS. Study selection : The inclusion criteria were five systematic reviews included in Alberta study and all randomized controlled trials obtained from their references. Study analysis : The acupuncture rationale, methods of stimulation, treatment regimen, and the practitioner's background were rated by FEAS, and the scores were compared with those by other methodological assessment tools. Results : The number of positive conclusions of high-rank RCTs by FEAS was the same as or higher than that of high-rank RCTs by other methodological assessment tools. Conclusions : We have analysed 5 systematic reviews and their objectives 58 RCTs using FEAS. Practitioner's background has been described slightly in some reviews and studies. It may directly influence the effectiveness of acupuncture negatively in the systematic reviews.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.456-458
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• 2004

We proposed a novel triode-type carbon nanotube field emitter arrays in which extracted gate is surrounded by CNT emitters. We carried out 3-dimensional numerical calculations of electrostatic potential for the proposed CNT-FEAs using the finite element method and compared the results with those obtained from the structure of conventional CNT-FEAs. It was found that the proposed structure could reduce the turn-on voltage for electron emission and improve beam focusing.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.685-688
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• 2002

In this paper, it is reported that the anode current changes at the constantly applied gate voltages and the current-voltage (I-V) characteristics of Si, Co silicide and Mo silicide field emitter arrays (FEAs) depending on vacuum level from a $10^{-9}$ torr to a $10^{-6}$ torr. The mechanism of the robustness of anode current degradation of Mo silicide FEAs under poor vacuum conditions can be explained by the model of tolerance for the oxygen adsorption and oxidation at the silicide surface. Also, we present the changes of emitting area and work function of the emitters according to vacuum level.

• 터널과지하공간
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• 제13권4호
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• pp.270-278
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• 2003

고준위 방사성폐기물 처분 연구 사업이 대중의 동의를 얻기 위해서는 처분 사업의 안전성에 대한 신뢰성 획득이 중요하다. 이를 위해서 투명하게 공개될 수 있는 종합성능평가(TSPA, Total System Performance Assessment)의 수행이 필요하다. 종합성능평가 수행에서 무엇을 평가할 것인가, 어떻게 평가할 것인가 그리고 각 이해 당사자들이 쉽게 이해할 수 있는 용어로 평가 결과들을 어떻게 전달할 것인가등과 같은 의견전달논의의 시발점이 된 것이 FEP(Features, Events, and Processes)시나리오 관련 연구라고 할 수 있는데 지금까지는 평가 영역 외부의 이해 당사자들이 평가 관련 상세 정보를 접하는 것이 쉽지 않은 일이었기 때문에 대부분의 경우 일방향(One-way communication) 의견 전달에 한정되어 왔다. 그러나 인터넷의 출현으로 성능 평가 등에도 쌍방향(Two-way communication) 의견 전달의 가능성이 높아지게 되었다. 본 연구에서는 FEP으로부터 AM(Assessment Methods Flow chart)까지의 형성 전 과정을 체계적으로 연결하여 웹 상에 나타내는 방법을 개발했다. 평가 관련 모든 요소들은 웹 기반 프로그램인 FEAS(FEp to Assessment through Scenario development) 내에서 시스템적 구성을 이루게 된다. 2003년부터 시작되는 연구에서는 FEAS 프로그램과 현재 개발 중에 있는 웹 기반의 품질보증(QA, Quality Assurance) 및 성능 평가(PA, Performance Assessment) 입력 자료 시스템을 하나의 시스템으로 통합하는 연구를 수행함으로써 든 이해 당사자들이 "처분장에서 생태계에 이르는 핵종들의 이동 경로에 대한 시나리오는 어떠한 것이며, 그 관계 결과들과 연구에 이용되는 실제 데이터들은 어떤 것인지"에 대해 쉽게 이해할 수 있도록 할 것이다.

• Journal of Information Display
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• 제2권3호
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• pp.66-71
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• 2001

MCFEDs (MOSFET-Contoolled Field Emission Displays) were fabricated to evaluate the validity of MCFEA for display application. The electrical properties of FEAs (Field Emitter Arrays), HVMOSFETs (High-Voltage MOSFETs), and MCFEAs (MOSFET-Controlled Field Emitter Arrays) were measured. The extraction gate voltage of the FEAs to obtain the anode current of 10 nA/tip was around 71 V. The breakdown voltages of the HVMOSFETs were above 81 V for all the samples. The I-V characteristics of the MCFEAs showed that the emission currents of the FEAs were well controlled depending on the control gate voltages of the HVMOSFETs. To avoid the harmful effects during the packaging process, the performance of the MCFEDs was evaluated in a high vacuum chamber. The emission images of the MCFEDs were controlled through very-through operation. From the comparison with a conventional FED, it was proven that the poor uniformity of FED could be improved through the integration with HVMOSFET.

• Journal of Information Display
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• 제1권1호
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• pp.63-69
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• 2000

In order to improve both the level and the stability of electron emission, Mo and Co silicides were formed from Mo mono-layer and Ti/Co bi-layers on single crystal silicon field emitter arrays (FEAs), respectively. Using the slope of Fowler-Nordheim curve and tip radius measured from scanning electron microscopy (SEM), the effective work function of Mo and Co silicide FEAs were calculated to be 3.13 eV and 2.56 eV, respectively. Compared with silicon field emitters, Mo and Co silicide exhibited 10 and 34 times higher maximum emission current, 10 V and 46 V higher device failure voltage, and 6.1 and 4.8 times lower current fluctuation, respectively. Moreover, the emission currents of the silicide FEAs depending on vacuum level were almost the same in the range of $10^{-9}{\sim}10^{-6}$ torr. This result shows that silicide is robust in terms of anode current degradation due to the absorption of air molecules.