• Nuclear Engineering and Technology
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• 제11권2호
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• pp.111-117
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• 1979

Time of flight Technique를 사용한 coincidence spectrometer에 의해 액체 형광물질(liquid scintillator) NE213의 전자와 양자에 대한 빛 방출량을 측정하였다. 이 실험에서 양자에너지 (3.2Mev, 4Mev, 5Mev, 6Mev)는 2Mev에서 9Mev에 이르는 여러 에너지 분포를 갖고 있는 Am.Be 중성자원을 사용하여 중성자 탄성산란의 각도(45$^{\circ}$ and 60$^{\circ}$)와 측정기간의 거리를 조절하므로서 얻었다. NE213액체발광물질의 빛 방출량은 전자 에너지에 대해 선형적인 응답을 보였으며 양자에 대한 응답은 에너지 증가에 따라 비선형적이었다. 빛의 세기도 전자에 의한 응답이 양자에 의한 것보다 약 세배 가랑 컸다. 본 실험결과는 Batchelor et at 이 발표한 실험결과와 거의 비슷했다.

• Spatial Information Research
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• 제11권4호
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• pp.391-407
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• 2003

최근 효율적 국토자원관리와 토지관리를 위해 국토정보와 토지관련 지적정보의 연계활용에 많은 관심이 모아지고 있으며, 도면정보로써 수치지도와 지적도를 포함하는 종합적인 정보체계의 구축에 많은 관심이 모아지고 있다. 본 연구에서는 수치지도와 지적도의 부정합 원인들에 대한 분석을 수행하고, 두 도면간의 정확한 중첩을 위해 지도의 변환에 활용되고 있는 대표적인 알고리즘에 대한 조사를 수행하여 중첩방안을 모색하였다. 또한 도면간 정합성 확보 방안에 대한 연구를 수행함으로써 수치지도와 지적도의 통합 데이터베이스 구축을 위한 기반을 마련하고 그 품질의 향상을 도모할 수 있는 방안을 제시하였다.

• Corrosion Science and Technology
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• 제12권6호
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• pp.265-273
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• 2013

Ti-stabilized 11 wt% Cr ferritic stainless steels (FSSs) for automotive exhaust systems have been experienced intergranular corrosion (IC) in some heat-affected zone (HAZ). The effects of sensitizing heat-treatment and silicon on IC were studied. Time-Temperature-Sensitization (TTS) curves showed that sensitization to IC was observed at the steels heat-treated at the temperature lower than $650^{\circ}C$ and that silicon improved IC resistance. The sensitization was explained by chromium depletion theory, where chromium is depleted by precipitation of chromium carbide during sensitizing heat-treatment. It was confirmed with the results from the analysis of precipitates as well as the thermodynamical prediction of stable phases. In addition, the role of silicon on IC was explained with the stabilization of grain boundary. In other words, silicon promoted the formation of the grain boundaries with low energy where precipitation was suppressed and consequently, the formation of Cr-depleted zone was retarded. The effect of silicon on the formation of grain boundaries with low energy was proved by the analysis of coincidence site lattice (CSL) grain boundary, which is a typical grain boundary with low energy.

• 한국환경과학회지
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• 제18권12호
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• pp.1427-1436
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• 2009

The purpose of this study was to explain community structure for actual vegetation and their environment variables in Anmyeon Island. Samples were collected for 106 plots using ZM phytosociology method and coincidence method. Actual vegetation were classified into three vegetations types(forest vegetation type, maritime vegetation type, lake vegetation type) and eleven community units. Pourthiaea villosa community in forest vegetation type was divided into 5 groups such as Carpinus coreana group, Pinus rigida group, Chamaecyparis obtusa group, Castanea crenata group and Typical group. Maritime vegetation type was divided into 3 communities, such as Vitex rotundifolia community, Koelreuteria paniculata community and Suaeda japonica community. V. rotundifolia community was subdivided into 2 groups, Rosa rugosa group and Diodia teres group. K. paniculata community was subdivided into 2 groups, Grewia biloba var. parviflora group and Typical group. Lake vegetation type was divided into 1 community, Nelumbo nucifera community. And it was entirely classified into 11 community units.

• 치과방사선
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• 제19권1호
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• pp.151-159
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• 1989

The author has studied radiographic bony cnages of mandibular condyle head in temporomandibular disorder patients using Oblique lateral transcranial projection, Orthopantomography, and Tomography. The bony change types and the frequencies of occurrence and the incidences of bony changes in three different radiographic techniques were examined. The coincidences of bony change types between the Oblique lateral transcranial projection and the lateral part of Tomogram, the Orthopantomogram and the medial part of Tomogram were also examined. The results were as follows: 1. The mean age of patients was 31.7 years and under 40 years were 24 patients, women werw 27 patients, men were 4patients. 2. The observable case of bony changes in all three radiographic techniques were 19 cases (50%) of 38 cases and the observable cases of bony changes in only Tomography were 5 cases(13.2%) 3. The most frequent radiographic bony change type was osteophyte and next orders were flattening, erosion, concavity. 4. The positional incidences of bony change in Tomogram were 31 cases in lateral part and 27 cases in central part. 5. The coincidence of bony change types between the Oblique lateral transcranial projection and the lateral part of Tomogram was 80%, and the coincidence between the Orthopantomogram and the medial part or Tomogram was 76.0%.

• 대한전자공학회논문지
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• 제4권2호
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• pp.3-15
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• 1967

감마선 후방산란을 이용한 철관 두께 측정용 측후계의 설계의 있어서 1/2인치 이하의 얇은 NaI 크리스털을 사용함으로써 계측부에 있어서 1개의 파고선별회로와 Anti-coincidence Circuit를 제거할 수 있다. 이 방식은 종래의 방식에 비하여 훨씬 회로가 경제적이면서도 거의 비슷한 정밀도와 안정도를 유지할 수 있다. 본논문에서는 위와 같은 새로운 방식에 의하여 설계, 시작된 측정기로서 지금까지 타연구자에 의하여 시도되지 않았던 200℃의 고온파이프의 관순측정실험을 행하였던바 상온에서의 측정치보다 불과 5%이내의 변화밖에 가져오지 않음을 실험적으로 확인하였다.

• Nuclear Engineering and Technology
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• 제48권3호
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• pp.778-784
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• 2016

HyperGam-U was recently developed to determine uranium enrichment based on ${\gamma}$- and X-ray spectroscopy analysis. The $XK_{\alpha}$ region of the uranium spectrum contains 13 peaks for $^{235}U$ and $^{238}U$ and is used mainly for analysis. To describe the X-ray peaks, a Lorentzian broadened shape function was used, and methods were developed to reduce the number of fitting parameters for decomposing the strongly overlapping peaks using channel-energy, energy-width, and energy-efficiency calibration functions. For validation, eight certified reference material uranium samples covering uranium enrichments from 1% to 99% were measured using a high-resolution planar high-purity germanium detector and analyzed using the HyperGam-U code. When corrections for the attenuation and true coincidence summing were performed for the detection geometry in this experiment, the goodness of fit was improved by a few percent. The enrichment bias in this study did not exceed 2% compared with the certified values for all measured samples.

• 치과방사선
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• 제10권1호
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• pp.47-55
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• 1980

The author analysed the routine radiographic changes and clinical symptoms of 205 cases of temporomandibular joint arthrosis. The clinical symptoms of the patients were classified and the morphological ylar head, articular eminence, and articular fossa were analized and discussed view point. The positional changes of condylar head and articular fossa relatation in TMJ arthrosis were observed. The frequencies of coincidence between the site of complaints and the site of the abnormal images which could be detected were examined. The results were obtained as follows; 1. Bone erosion, deformity, marginal proliferation and sclerosis were selected from many abnormal images as the radiographic diagnostic criteria of TMJ arthrotic lesions. 2. Abnormal radiographic findings were revealed in 150 cases (73.9%) of 205 total TMJ arthrosis cases and site with abnormal findings coincided with the site of complaints in 106 cases (70.7%) of 150 cases and coincidence rates were higher above fourth decades than below third decades. 3. Sclerosis of the abnormal radiographic findings could be found more often below third decades than above fourth decades. 4. The positional changes of condylar head were revealed in 176 cases (85.9%) of 205 total cases. 5. Pain complaints were revealed in 170 cases(82.9%) and clicking sounds were revealed in 120 cases (58.6%) of clinical symptoms of TMJ arthrosis. 6. No tendency was found so far the differential diagnosis between pain dysfunction syndrom and osteoarthrosis of TMJ.

• 한국광학회지
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• 제15권5호
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• pp.399-404
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• 2004

매개하향변환과정에서 발생한 640 nm와 660 nm 파장을 갖는 광자쌍의 진동수 얽힘상태를 이용하여 양자간섭실험을 수행하였다. 두 광자의 파장에 대응하는 각진동수가 각각 $\omega$$_1$과 $\omega$$_2$인 광자쌍을 간섭계의 출구에 놓인 두 검출기로 서로 다른 진동수의 광자들을 동시계수할 때, 광의 결맞음 시간이내에서 두 광자가 빔분할기에 도달하는 시간 간격의 변화 $\delta$$\tau$에 따라 동시계수가 변하는 간섭무늬를 관측하였다.

• Journal of Periodontal and Implant Science
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• 제38권2호
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• pp.199-206
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• 2008

Purpose: Variation in the morphology of gingival papilla may be determined by the shape and position of anatomic crown as well as contact area and embrasure form of individual teeth. However, periodontal biotype classification is regarded to be subjective because of the lack of definite criteria. In this study, we defined the objective parameters which constitute the periodontal biotype and measured their relationship. Materials and Methods: 109 of dental casts were prepared using three dimensional scanner and specialized reconstruction software, then acquiredvirtual models were sent to the 20 professional dentists to define the specific periodontal biotypes. Several parameters around periodontal structures were measured from the virtual models; facial surface area of the anterior tooth (AT), anterior papillary area (AP), proportion of the dento-papillary complex, clinical papillary length (PL), and clinical papillary angle (PA). Statistical analysis was performed to confirm the relationship among parameters. Results: Coincidence rate of periodontal biotype within observers was $63.77{\pm}16.05%$. Coincidence rate between observers was $76.15{\pm}16.43%$. Among the parameters measured, PL showed the most positive correlations and PA presented the most negative correlations. The parameter of the AP and PL of six maxillary anterior teeth showed significant correlation coefficient. Conclusion: Anterior papillary area and clinical papillary length would be objective parameters for determining the consistent periodontal biotypes.