• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1207-1210
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• 2005

The MgO protective layer provides protection from the discharge, lowers the discharge voltage and prolongs the AC-PDP lifetime. We have investigated the characteristics of degradation of MgO protective layer, which correlates to the image-sticking[1] and the lifetime in AC-PDP. The degraded MgO have been changed the surface morphology of MgO. It was found that panel lifetime depended on degradation of MgO protective.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2010년도 춘계학술대회
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• pp.262-268
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• 2010

Organic light emitting diode is developed fast from 1963 after discovering electric light emitting phenomenon. First PMOLED(passive matrix OLED) product is manufactured and AMOLED(active matrix OLED) using TFT(thin film ransistor) is now in the center. PMOLED is mainly mounted at sub display. but AMOLED is mounted at main display. Also AMOLED expand the market to PMP(portable multimedia players), navigation and TV. Even thought OLED's market is opening to many applications, OLED is worried about lifetime until now. That's appeared in market in a very short time and is not known well about result of OLED's lifetime and reliability test. And there is no standard ssessment method and not enough study to standardization the method. A study's purpose is reduce the time for life test by accelerated current and it can do production possible design by accelerated life model in design phase. It's must be add to process variables and design variables(like ratio of light emitting, organic material structure, condition of aging, etc) to make the best use of supplied accelerated lifetime model in this paper. In terms of lifetime it needs each criterion of applications because of image sticking. In conclusion, it's possible to discover new defect because there is not much time to be opened in market and develop a method of manufacturing process & materials, so we need to study on the subject of this paper continuously.

• 대한후두음성언어의학회지
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• 제18권2호
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• pp.96-101
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• 2007

Laryngopharyngeal reflux (LPR) is the retrograde movement of gastric contents into the larynx, pharynx, and upper aero-digestive tract. LPR differs from gastroesophageal reflux in that it is often not associated with heartburn and regurgitation symptoms. Otolaryngological manifestations of acid reflux include a wide range of pharyngeal and laryngeal symptoms. Belafsky et al. developed a useful self-administered tool, the reflux symptom index (RSI), for assessing the degree of LPR symptoms. Patients are asked to use a 0 to 5 point scale to grade the following symptoms: 1) hoarseness or voice problems; 2) throat clearing; 3) excess throat mucus or postnasal drip ; 4) difficulty swallowing; 5) coughing after eating or lying down; 6) breathing difficulties ; 7) troublesome or annoying cough; 8) sensation of something sticking or a lump in the throat; 9) heartburn, chest pain, indigestion or stomach acid coming up. A RSI score greater than 13 is considered abnormal. As there is no validated instrument to document the physical findings and severity of LPR, Belafsky et al. developed an eight-item clinical severity scale for judging laryngoscopic finding, the reflux finding score (RFS). They rated eight LPR-associated findings on a scale from 0 to 4 : subglottic edema, ventricular obliteration, erythema/hyperemia, vocal-fold edema, diffuse laryngeal edema, posterior commissure hypertrophy, granuloma/granulation tissue, and thick endolaryngeal mucus. A RFS score of greater than 7 was found to suggest LPR-associated laryngitis. Although both indices (RSI and RFS) are widely used, there is some controversy about their validity (sensitivity and specificity) and reliability (intra-rater and inter-rater) in LPR diagnosis and treatment. We discuss the validity and reliability of RSI and RFS with literature review.

• 컴퓨터교육학회논문지
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• 제14권3호
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• pp.1-12
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• 2011

'정보기기의 구성과 동작' 영역은 5차 교육과정에서 개정 교육과정에 이르기까지 지속적으로 정보교과의 교육과정에 포함되어 왔다. 그러나 이 영역에 대한 내용선정이나 교수방법 등과 같이 교육적 본질에 대한 논의는 전혀 이루어지지 않았다. 따라서 본 연구는 현대 교육과정의 관점에서 '정보기기의 구성과 동작' 영역의 탐구적 경향을 분석하였다. 4개의 교과서를 대상으로 분석한 결과, 1개의 교과서만이 탐구적 교과서로 나타났다. 연구 결과를 토대로 본 연구는 교과서의 제작에서는 내용의 중요성과 학습활동의 관점을 함께 고려할 것, 융복합의 시대에 기본이 되는 교과로서 단순 암기의 지식보다는 성찰을 제공하는 교과임을 고려해야 함을 제안하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.365-369
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• 2001

EAF's dust has been treated mainly by pyrometallurgical reduction process in rotary kiln furnace to recover valuable metal elements such as Zn and to avoid the disposal of hazardous materials to waste. Recently, hydrometallurgical eletrowinning of zinc from a zinc-amino chloride solution obtained by the leaching of EAF's dust was developed to recover high grade zinc metal from EAF’s dust. But there are some disadvantages in each process such as difficulty of operation condition control and sticking problem in kiln process and low extractability and recovery of zinc owing to insoluble zinc-ferrite in electrowinning process. We propose a new combined process of pyrometallurgical one and hydrometallurgical one to treat EAF's dust efficiently and economically. In this study, ammonium chloride solution leaching of crude zinc oxide recovered from reduction of EAF's dust was carried out to find out the efficiency of zinc extraction from it and the possibility for performance of eletrowinning in the proposed process. Effects of various leaching variables ruck as leaching temperature, concentration of leaching solution and leaching time were investigated. And the leaching results of the crude zinc oxide were compared with those of EAF's dust. The extraction percents of zinc in ammonium chloride solution leaching of the crude zinc oxide recovered from reduction of EAF's dust were above 80% after 60 minutes of leaching under the leaching condition of 4M NH$_4$CI concentration and above leaching temperature of 7$0^{\circ}C$. And the concentrations of zinc in the leached solution were obtained above 50g/$\ell$. The activation energy calculated for zinc extraction in NH$_4$CI leaching was 58.1 KJ/㏖ for EAF's dust and 15.8 KJ/㏖ for the crude zinc oxide recovered from reduction of EAF's dust.

• 디자인학연구
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• 제17권4호
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• pp.365-374
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• 2004

비교적 새로운 역사 분야라는 이유로 또한 다양한 인공물과 그 디자인과 제조, 유통과정에서 비롯되는 주제의 다양성에 따라 디자인사 연구는 상당히 도전적인 분야로 인식되고 있다. 그러나 같은 이유로 디자인사는 스스로 연구의 한계와 난점을 드러내고 있다. 사료의 무한정한 다양성도 문제로 들 수 있다. 근대적 생산기술의 도입에 따라 디자인 대상으로서 인공물의 증가는 생물 다양성의 수백 배를 넘었으며 여전히 기하급수적 증가 일로에 있다. 이는 디자인 역사가가 이 모든 것들을 다루기에는 현실적으로 불가능함을 뜻한다. 둘째, 이러한 인공물의 엄청난 증폭 현상은 최근 170년간의 특수한 현상으로서 이 기간을 하나의 역사 연구 단위로 보기에는 너무 짧고, 또한 현재에도 진행 중이기 때문에 수평 비교를 위한 거시적 안목의 설정이 불가능하다는 것이다. 따라서 이에 대한 객관적인 역사 평가 역시 내리기 어렵다는 점이다. 셋째, 디자인사의 연구 대상인 ‘디자인은 많은 경우 분야와 대상을 동시에 나타내어 그 구분이 어렵다. 즉 디자인은 디자인 행위, 혹은 디자인제(작)품 등의 뜻으로 복합적으로 쓰임으로써 디자인사가 정교히 서술할 만한 주제로 정리되지 못하고 있다. 본 연구는 이런 문제 의식에 기초하여 우리나라에 간행된 여러 디자인사 연구서를 비교 검토함으로써 역사 연구 일반의 체계적 기술을 위한 기초를 마련하고자 한다.

• 한국진공학회지
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• 제6권2호
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• pp.159-164
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• 1997

X-선 광전자 분광법 (x-ray photoelectron spectroscopy: SPS)과 반사 고에너지 전 자 회절법(reflection high energy electron diffraction: RHEED)을 이용하여 상온과 고온(약 300~$500^{\circ}C$)에서 알칼리금속(AM)/Si(111)7$\times$7표면에 1 monolayer(ML)의 AM을 흡착시키면 Si(111)7$\times$7표면에 비해 산소의 초기 부착 계수(initial sticking coefficient)와 산소의 포화량 은 증가하지 않았다. Si(111)7$\times$7-AM표면에 산소의 주입량을 증가시키면서 측정한 O ls 스 펙트럼으로부터 AM이 흡착된 Si(111)7$\times$7표면에 흡착되는 산소원자는 Si-O, AM-O 두 종 류의 결합형태를 가지는 것으로 생각되며 이중에서 AM-O 결합의 산화과정상에서의 역할 에 대하여 논의하였다. 상온과는 달리 고온에서는, Si(111)3$\times$1-AM표면으로 구조가 변화하 면서 산소의 흡착이 급격히 떨어지는 것을 관측할 수 있었다. 이때 3$\times$1-AM표면을 형성시 키는 AM종류의 산화에 대한 의존성을 살펴보았다.

• 복식
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• 제50권3호
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• pp.31-42
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• 2000

This study investigated the history of whakwan (crown, 화관(花冠)) and classified the types of whakwan accordint to its structure. Whakwan seemed to originate from the custome of sticking flowers in the hair which was the reflection of human desire of pursuing the beauty . The whakwan fist appeared in the Oriental painting during the Tang period and became fashionable is Song. It is not clear when whakwan was introduced into Korea, but is assumed to be greatly influenced by the Song whakwan. The Korean record on whakwan showed on whakwan showed fro the fist time in the reign of Kimg Sejong and whakwan was used for the costume of a dancing boy. Through the present type of whakwan appeared only one in the painting of the reign of King Seonjo, there are a number of whakwans in the lattern part of the Chosun dynasty, Now there exist three types of whakwan in Korea. The first type is similar to that of Chokduri in decoration . But it was made of paper, had the double structures of inner and outer part and was decorated by Yangkwan's vertical lines of gilt paper. The second type is the whakwan made of artifical flowers with various color cords and was widely used in Geesung and Pyungyang regions. Finally, though the third type is similar to Sabangkwan, its outside was decorated gaudilly iby Dangchae (colorful painting ) and it was assumed that dancing bodys put it on their head for various banquets. Out of these three types, the first is most representative , Black was the popularly used color for the first type and this type was used either for brides on wedding ceremonies or for shamans or palace dancers. The second type was widely used in Gaesung and Pyungyang regions. But the differences in the shape of whakwan of the two regions showed the regional characteristics of traditional costumes in Korea. The third type was most likely to be used in the dance for palace banquets, but it is necessary to further investigate whether shamans actually wore this type of whakwan.

• 한국재료학회지
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• 제27권2호
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• pp.63-68
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• 2017

A black nickel oxide powder, one of the commercial nickel oxide ores, was reduced by hydrogen gas in a batch-type fluidized-bed reactor in a temperature range of 350 to $500^{\circ}C$ and in a residence time range of 5 to 120 min. The hydrogen reduction behavior of the black nickel oxide was found to be somewhat different from that of green nickel oxide ore. For the black nickel oxide, the maximum temperature (below which nickel oxide particles can be reduced without any agglomeration) was significantly lower than that observed for the green nickel oxide. In addition, the best curve fittings of the Avrami model were obtained at higher values of the overall rate constant "k" and at lower values of the exponent "m", compared to those values for the green nickel oxide. It may be inferred from these results that the hydrogen reduction rate of the black nickel oxide is faster than that of the green nickel oxide in the early stages, but the situation reverses in the later stages. For the black nickel oxide ore, in spite of the low temperature sintering, it was possible to achieve a high degree fluidized-bed reduction at lower temperatures and at lower gas consumption rates than was possible for the green nickel oxide. In this regard, the use of black nickel oxide is expected to yield a benefit if its ore price is sufficiently lower than that of the green nickel oxide.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.213-216
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• 2001

Etching behaviors of ferroelectric $YMnO_3$ thin films were studied by an inductively coupled plasma (ICP). Etch characteristic on ferroelectric $YMnO_3$ thin film have been investigated in terms of etch rate, selectivity and etch profile. The maximum etch rate of $YMnO_3$ thin film is $300{\AA}/min$ at $Ar/Cl_2$ of 2/8, RF power of 800W, dc bias voltage of 200V, chamber pressure of 15mTorr and substrate temperature of $30^{\circ}C$. Addition of $CF_4$ gas decrease the etch rate of $YMnO_3$ thin film. From the results of XPS analysis, YFx compounds were found on the surface of $YMnO_3$ thin film which is etched in $Ar/Cl/CF_{4}$ plasma. The etch profile of $YMnO_3$ film is improved by addition of $CF_4$ gas into the $Ar/Cl_2$ plasma. These results suggest that fluoride yttrium acts as a sidewall passivants which reduce the sticking coefficient of chlorine on $YMnO_3$.