• 한국정보통신학회논문지
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• 제19권9호
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• pp.2029-2036
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• 2015

하둡 MR(MapReduce)는 매퍼(Mapper)의 출력을 리듀서(Reducer)의 입력으로 전달하기 위해 파티션 함수(Partition Function)을 사용한다. 파티션 함수는 키에서 해쉬 값을 계산한 후 리듀서 개수로 나머지 연산을 수행하여 대상 리듀서를 결정한다. 기존 파티션 함수는 키의 편중도에 민감하여 잡이 균등하게 배분될 수 없었다. 잡이 균등하게 배분되지 못하면 특정 리듀서들의 처리 수행 시간이 길어져 전체 분산 처리 수행 성능에 영향을 주게 된다. 이에 본 논문은 VPT(Virtual Partition Table)을 제안하고 편중도가 심한 데이터에 VPT을 적용하여 실험을 수행 하였다. 적용된 VPT는 기존 파티션 함수와 대비하여 평균 3초 정도 성능향상이 발생하였으며, 데이터 처리량이 증가할수록 성능 향상 폭이 증가할 것으로 예상된다.

• 한국인쇄학회지
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• 제22권2호
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• pp.123-138
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• 2004

The video phone tube (VPT) of monochrome CRT have utilized home door phone, fish-finder and the rear watch monitors. Phosphor screen formation is made by electrodeposition spin coating and thermal transfer methods etc. Recently, thermal transfer method was developed, as a novel method, to form the phosphor surface for mnonchrom VPT. This method have advantages of simple process, automatization, clean environment, saving raw material and saving running-cost. In this study, it was developed new phosphor of VPT, and tested about phosphor paste properties. An experimental studies of VPT as a new phosphor property and improved VPT's manufacturing process shortening and brightness. As thermal transper method is a paste processing, it is important that rheology of phosphor effects on the formation of phosphor screen. Hence this paper was studied rheology properties of phosphor paste and the formation of phosphor screen had looked most suitable condition. Experimented thermal separation properties of low calcination temperature resin and the result analyzed comparison by TGA. Also, examined calcination properties to reduce remaining binder phosphor.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.593-594
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• 2006

A novel thermal transfer method was developed to form the phosphor screen for VPT(Video Phone Tube). This method have advantages of simple process, clean environment, saving raw material and running-cost comparison of electrodeposition, spin coating of conventional methods. But now applying phosphor screen for thermal transfer method has been formed three layers (phosphor layer, ITO layer and thermal adhesive layer) on the PET film as substrate. This is complex process, run to waste of raw-material and require of high cost. Also ITO paste at present has been imported from Japan. To improve these problems, we have manufactured phosphor screen formed by two layers (phosphor layer and ITO layer). We have developed ITO paste that had both conductive and excellent thermal transfer abilities, made it of domestic raw-material.

• Journal of Dental Anesthesia and Pain Medicine
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• 제19권4호
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• pp.227-233
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• 2019

Background: Dental anxiety in children is a major barrier in patient management. If dental anxiety in pediatric patients is assessed during the first visit, it will not only aid in management but also help to identify patients who are in need of special care to deal with their fear. Nowadays, children and adults are highly interested in multimedia and are closely associated with them. Children usually prefer motion pictures on electronic devices than still cartoons on paper. Therefore, this study was conducted to evaluate a newly designed scale, the animated emoji scale (AES), which uses motion emoticons/animojis to assess dental anxiety in children during their first dental visit, and compare it with the Venham picture test (VPT) and facial image scale (FIS). Methods: The study included 102 healthy children aged 4-14 years, whose dental anxiety was measured using AES, VPT, and FIS during their first dental visit, and their scale preference was recorded. Results: The mean anxiety scores measured using AES, FIS, and VPT, represented as $mean{\pm}SD$, were $1.78{\pm}1.19$, $1.93{\pm}1.23$, and $1.51{\pm}1.84$, respectively. There was significant difference in the mean anxiety scores between the three scales (Friedman test, P < 0.001). The Pearson's correlation test showed a very strong correlation (0.73) between AES and VPT, and a strong correlation between AES and FIS (0.88), and FIS and VPT (0.69), indicating good validity of AES. Maximum number of children (74.5%) preferred AES. Conclusion: The findings of this study suggest that the AES is a novel and child-friendly tool for assessing dental anxiety in children.

• 한국인쇄학회지
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• 제22권2호
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• pp.73-82
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• 2004

A thermal transfer method was developed novel method to form the phosphor screen for monochrom VPT. This method have advantages of simple process, clean environment, saving raw material and running-cost. But now applying phosphor screen for thermal transfer method has been formed three layers (phosphor layer, ITO layer and thermal adhesive layer) on the PET film as substrate. This is complex process, consumption of raw-material and require of high cost. Also ITO paste at present has been imported from Japan. To improve these problems, we have developed ITO paste as conductive paste by using ITO sol and binder resin (AA3003). Ito paste as developed in this study has both conductive and excellent thermal transfer abilities. Thus we could manufacture phosphor screen formed two layers (phosphor layer and ITO layer).

• 한국정보관리학회:학술대회논문집
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• 한국정보관리학회 2006년도 제13회 학술대회 논문집
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• pp.153-160
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• 2006

통제어휘를 사용하는 주제색인 작업에서 색인전문가를 효율적으로 지원할 수 있는 자동색인 방법으로 프로파일 방법의 성능과 특성을 검토해 보았다. 자동색인의 성능에 영향을 미치는 주요 요인들을 검토한 다음, 동일한 조건 하에서 프로파일 기반 방법과 다른 방법들(NB, SVM, VPT)의 성능을 비교하였다. 그 결과, 로치오 알고리즘에 기초한 프로파일을 사용하는 방법이 다른 방법들에 비해 저성능이라는 일부 평가를 일반화하기는 어렵다는 사실이 실험을 통해 드러났다. 또한, 후보 디스크립터 리스트의 생성을 통하여 색인전문가의 색인작업을 지원하는 반자동색인의 경우, F$_1$척도로는 SVM, VPT와 동등한 수준에 있으면서 재현율이 상대적으로 높은 수준인 프로파일 기반 방법을 우선적으로 고려해 볼 수 있을 것이다.

• 정보관리학회지
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• 제23권3호
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• pp.69-89
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• 2006

로치오 알고리즘에 기초한 통제어휘 자동색인 또는 텍스트 범주화에서 적용되어 온 여러 성능 요인들을 재검토하였고, 성능 향상을 위한 기본적인 방법을 찾아보았다. 또한, 동등한 조건에서 통제어휘 자동색인을 위한 로치오 알고리즘 기반 방법의 성능을 다른 학습기반 방법들의 성능과 비교하였다. 결과에 따르면, 통제어휘 자동색인을 위한 로치오 기반의 프로파일 방법은 구현의 용이성과 컴퓨터 처리시간 측면의 경제성이라는 기존의 장점을 그대로 유지하면서도, 다른 학습기반 방법들(SVM, VPT, NB)과 거의 동등하거나 더 나은 성능을 보여주었다. 특히, 색인전문가의 색인작업을 지원하는 반-자동 색인의 목적으로는 비교적 높은 수준의 재현율을 유지하면서 학습 데이터의 증가에 따라 정확률이 크게 향상되는 로치오 알고리즘을 이용한 방법을 우선적으로 고려할 수 있을 것이다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.250-250
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• 2011

Zinc oxide (ZnO) structures have great potential in many applications. Currently, the most commonly used method to grow ZnO nanostructres are the vapor transport method (VPT). The morphology of the ZnO structures largely related to the growth conditions, including growth temperature, distance between the substrate and source, and gas ambient. Previously ZnO nanosturecutres with high crystallinity were obtained at the growth temperature of 800$^{\circ}C$, in the argon and oxygen gas ambient. In this study, we report the properties of the ZnO nanostructures, which were synthesized on Au-catalyzed Si substrate by VPT, using a mixture of ZnO and graphite powders as source material under the different condition, including gas ratio of argon/oxygen and distance between substrate and source at the growth temperature of 800$^{\circ}C$. The structural and optical properties of the ZnO nanostructures were investigated by field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and photoluminescence (PL).

• Journal of Preventive Medicine and Public Health
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• 제28권4호
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• pp.765-771
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• 1995

치과용 핸드피스에서 발산하는 고주파수의 진동에 의한 일시적 진동감각역치 변화를 관찰하고자 치과위생병 28명을 대상으로 34,000rpm의 low-speed handpiece를 진동기구로 사용하였다. 진동에 폭로시키기 전과 후, 치과의사가 스케일링시 취하는 작업자세에 5분간 폭로시킨 후의 진동감각역치를 청력계기의 골전도진동기를 사용하여 250 Hz에서 그들이 주로 사용하는 손의 제2지두수에서 측정한 결과, 각각 $23.5{\pm}3.5dB,\;30.8{\pm}4.2dB,\;23.7{\pm}4.6dB$로 진동에 5분간 폭로시킨 후의 역치가 폭로 전에 비해 7.3dB의 유의한 증가가 있었다(p<0.001). 진동폭로 전후의 차이에 따른 분포를 보면, 10 dB 내외로 증가한 사람이 71.4%로 대부분이었고 16 dB의 증가가 가장 높았다. 진동 폭로 전의 진동감각역치와 신장, 체중, 체질량 지수와의 상관관계는 각각의 상관계수가 0.0360, -0.1657, -0.2641로 통계적 유의성은 없었으며, 흡연에 따른 차이도 흡연군(N=20)과 비흡연군(N=8)의 진동감 각역치가 각각 23.1 dB, 24.6 dB로 그 차이 가 없었다. 본 연구 결과로 볼 때 핸드피스와 같은 고주파-진동기구를 사용하는 치과의사 및 치과위생사에게서 진동감각역치의 변화가 예상되며, 말초신경병증의 원인이 될 수 있는 작업자세에 의한 장기간의 영향 및 아말감 충전시 사용하는 수은의 영향에 대해서도 연구가 필요할 것으로 생각된다.

• 한국환경과학회지
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• 제14권8호
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• pp.801-810
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• 2005

The phosphor and ITO(Indium Tin Oxide) films for video phone tube (VPT) were simply prepared by the screen printing and thermal transfer methods. The increasing order of thermal firing of acrylic binder for phosphor and ITO was M6003 < M6664 < A/A 1919 < M500l < M670 1 and all mass of binders were perfectly decomposed at lower temperature than $400^{\circ}C.$ After thermal firing of phosphor paste, the residual of binder on the surface of phosphor could not be found by SEM. Aerosil as thickner provides the thixotropy property for phosphor paste but decrease the brightness of phosphor screen as residual after thermal firing. Since the thixotropy of M5001 binder without aerosil was shown and the storage modulus of phosphor paste by increasing the angular frequency was not nearly changed and the decrease of the storage modulus of phosphor paste by increasing the strain was remarkably shown. It was possible to prepare the phosphor paste which was predominant in the plate separation and the reproduction of pattern after the screen printing. Since the addition of dispersing agent to improve the printing process decreases the electrical conductivity and light transmission of ITa film, it could be found to be necessary the development of binder for phosphor paste that decreases the amount of dispersing agent possibly and does not use the aerosil as additive.