• Journal of The Korean Association For Science Education
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• v.31 no.5
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• pp.709-719
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• 2011

The purpose of this study was to identify the differences in classification skills shown in classification activities between the gifted and regular students in elementary schools. The subjects for the research consisted of six gifted students in an institute for the gifted for science annexed to P school district in Gangwon-do and 6 students at B and M general elementary schools. Results were as follows: The time taken for classification activities of the gifted was shorter than regular regardless of subjects for classifying. The number of standards for classifying for the gifted was more than regular students. Coefficient for measuring classification skills of the gifted was higher than regulars regardless of age. Consequently, there was a difference in the time taken for classifying and generating the number of standards and in a numerical index of classification activities performed at science classes between the science gifted and the regular students.

• Journal of Sensor Science and Technology
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• v.11 no.6
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• pp.335-341
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• 2002

In this paper, we investigated a novel UV sensor using evanescent field coupling between the side polished fiber and photo-functional polymer waveguide. It was found that resonant wavelength shifts occur due to variation in the refractive index of polymer planar waveguide for its photo-functional properties on exposed UV. Spiroxazine (photochromic dye) was used as the planar waveguide. The resonant wavelength responses were exhibited at 1.44 nm/mW, 1.64 nm/mW, and 1.78 nm/mW when UV irradiations were exposed for 20 seconds, 30 seconds, and 40 seconds, respectively. The recovery time of sensor was independent of UV exposure power and 90% recovery time was 100 seconds.

• Archives of Plastic Surgery
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• v.38 no.6
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• pp.740-746
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• 2011

Purpose: In the treatment of the unilateral cleft lip nasal deformities, the correction of the low-nostril height and short-columella are very difficult problems. We report the treatment outcomes of web uni-limb Z-plasty used for correction of unilateral cleft lip nasal deformities by using photographic analysis. Methods: A total of 36 patients with unilateral cleft lip nasal deformities were enrolled in this study, who underwent web uni-limb Z-plasty and were followed up for at least 6 months. First, a triangular flap was made on the medial side of alar-columella web. The nostril apex of cleft side was corrected to a higher point compared to noncleft side by 2 mm. The flap was transposed into the defect of the vestibule. To reduce the bulging of the flap, horizontal cinching sutures were added. Postoperative outcomes were evaluated by using photographic analysis. 2 indices and 1 angle were measured on their photographs taken before and after the surgery. Symmetry was also evaluated by means of the noncleft side to cleft side index. For anthropologic assessment, observers described postoperative outcomes, using Ordinary Scale Method. Results: The postoperative values obtained in photographic analysis improved compared to preoperative ones. More improving anthropologic assessment was shown in post-than pre-operative. Conclusion: Although, further long term follow up is needed, we found this technique to be an effective procedure to the symmetry of nostril apex level and the lengthening of columella in the unilateral cleft lip nasal deformities.

• Journal of Chest Surgery
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• v.30 no.10
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• pp.1040-1043
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• 1997

We report a patient who suffered from bronchiolitis obliterans organizing pneumonia(BOOP) after Ivor Lewis operation for esophageal cancer. The patient presented low grade fever, dry cough and mild dyspnea at day after operation. Chest roentgenograms and chest CT revealed bilateral patchy and infiltrative shadows. The respiratory symptoms worsened and respiratory failure developed with mild elevation of WBC count despite of conservative treatment. An open lung biopsy was done and the biopsy specimen showed bronchiolitis obliterans organizing pneumonia(BOOP). After several weeks of steroid therapy, there were marked clinical, physiological and roentgenographic improvements. Our experience suggests that BOOP may be one of the underlying pathology in a number of patients presenting with ARDS after thoracotomy. Since steroid therapy may improve survival in these patients, thoracic surgeons should heighten their index of suspicion for this entity. Early histologic diagnosis should be considered in patients with treatment-resistant ARDS after thoracotomy.

• Journal of Oral Medicine and Pain
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• v.22 no.2
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• pp.241-252
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• 1997

본 연구는 임상검사 및 방사선 사진상 악관절장애로 진단된 환자중 물리치료,악관절 안정장치 등의 보존적 치료방법을 시행하였으나 증상의 개선이 별로 없는 퇴행성 관절질환이나 중등도의 개구제한을 가진 환자를 대상으로하여 aspirin을 이용한 활액성분 분석 및 악관절 도약술과 sodium hyaluronate의 주입을 시행한후 이에 따른 치료결과를 평가하기 위하여 시행되었다. 평균연령이 31.2세(21-42세)인 11명의 악관절 장애환자를 대상으로 하였다. 악관절 도약술과 sodium hyaluronate의 주입은 악관절의 동통과 개구제한의 해소를 위해 시행되었으며 그 결과를 시술전, 시술 즉시, 시술 1주후 및 4주후로 나누어 분석하였으며 활액 채취시 생리식염수의 희석에 의한 활액성분의 농도 변화에 따른 오차를 막고자 활액과 혈액내의 aspirin의 농도차를 이용하여 정확한 활액 성분농도를 측정하였다. 이상의 연구를 통하여 다음과 같은 결론을 얻었다. 1. 전체 환자의 생리식염수에 의한 악관절 활액의 희석계수는 1.4-12.9(5.5$\pm$4.2)로 상당히 넓은 범위를 나타내었다. 2. 만성 폐구성 과두걸림 환자군(n=7)의 생리식염수에 의한 활액의 희석계수 (6.2$\pm$3.5)는 퇴행성 관절질환을 갖는 환자군(4.4$\pm$5.7, n=4)과 유의한 차이가 없었다. 3. 만성폐구성 과두걸림군과 퇴행성 관절 질환군간의 활액성분의 농도는 유의한 차이가 없었으나 희석계수를 이용한 수정된 Hyaluronic acid와 총단백질의 농도는 만성 폐구성 과두걸림군의 경우에서 유의하게 더 높게 나타났다. 4. 악관절 도약술과 sodium hyaluronate의 주입 직후 만성 폐구성 과두걸림 환자군의 경우 평균 8.3mm의 추가적인 개구 증가로 유의한 차이가 관찰되었고 퇴행성 관절질환의 경우 평균 1.3mm의 추가적인 개구증가가 있었으나 유의한 차이가 관찰되지 못했다. 5. 시술전, 시술 1주후 및 4주후의 여러 검사항목을 비교한 결과 두 군에서 모두 시간의 경과에 따라 기능이상 및 동통 감소의 경향을 나타내었으나 유의하지는 않았으며 만성 폐구성 과두걸림의 경우 기능장애지수(dysfunction index) 와 최대개구시 동통의 정도는 시술전과 시술 4주후간에 유의한 차이가 관찰되었다.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.6
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• pp.53-58
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• 2004

A novel UV sensor was manufactured and characterized using evanescent field coupling between photochromic dye dispersed polymer waveguide and side polished fiber. The spiroxazine (photochromic dye) dispersed polymer was used as planar waveguides. The resonant wavelength was shifted owing to refractive index variation of planar waveguide on exposed UV because of its photo-functional properties. The sensitivities are $1.21{\mu}W/mw$ and $2.75{\mu}W/mw$ when UV intensities increased after exposure times were fixed at 3 seconds and 5 seconds, respectively. Output optical power according to UV intensity increases and saturation time decreases as the intensity of UV radiations increases.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.4
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• pp.20-25
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• 2010

An integrated Mach-Zehnder interferometric sensor operating at 632.8 nm was designed and fabricated by the technology of planar rib waveguides. Rib waveguide based on silica system ($SiO_2-SiO_xN_y-SiO_2$) was geometrically designed to have single mode operation and high sensitivity. It was structured by semiconductor fabrication processes such as thin film deposition, photolithography, and RIE (Reactive Ion Etching). With the power observation, propagation loss measurement by cut-back method showed about 4.82 dB/cm for rib waveguides. Additionally the chromium mask process for an etch stop was employed to solve the core damaging problem in patterning the sensing zone on the chip. Refractive index measurement of water/ethanol mixture with this device finally showed a sensitivity of about $\pi$/($4.04{\times}10^{-3}$).

• Journal of the Korean association of regional geographers
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• v.5 no.1
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• pp.137-150
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• 1999

Five land use change detection methods were applied to 1994 and 1997 Landsat Thematic Mapper (TM) images of Pook-Gu, Taegu city to determine the land-cover changes between the two dates. The two images were coregistred to UTM coordinates. A post-classification comparison method was the most commonly used quantitative method of change detection. A pre-classification comparison method was more effective method to change detection of land cover than a post-classification comparison method. Two indices were used to assess the accuracies of the studied methods. A image differencing method was found to be most accurate for detecting change verse no change among five land use change detection methods. The difference image of band 2 was found to be most accurate. The overall accuracy and Kappa index agreement of the difference image of band 2 were 0.810 and 0.447.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.3
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• pp.145-152
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• 1989

Volume phase diffraction grating is formed in 5${mu}m$ Agfa 8E75 photographic emulsion film using He-Ne laser. It is dependent on the chemical processing rather than materials themselves that high diffraction efficiency can obtained in silver halide emulsions. With potassium dichromate bleach and alcohol drying, overall efficiency of 71% (81% after allowing for reflection at the two surfaces) has been achieved at an exposure of 180${mu}J/cm^2.$ Dichromate cross-linkage and air void by rapid dehydration increase refractive index modulation depth. The grating is swollen, which is newly identified by Scanning Electronic Microscope(SEM) photography, and it causes on-Bragg at larger angle than the recording angle. It is pointed out that controlling the emulsion thickness has an important role as a potential source for high diffraction efficiency.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.459-459
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• 2021

오래 전부터 농업용수 취수 등의 목적을 위해 설치된 하천 내 횡단구조물이 약 34,000개에 달하고, 홍수피해 방지를 위해 하천변을 따라 많은 제방이 설치되어 있다. 특히 보, 낙차공, 교각 보호공 등의 횡단구조물은 흐름의 단차를 발생시킴으로써 어류의 이동 등 하천의 종적 연속성을 훼손 또는 단절하고 있어 하천 수생태계 연속성 확보 측면에서 매우 중요한 요인으로 볼 수 있다. 하천 종적 연속성과 관련된 연구는 북미, 호주, 유럽, 일본 등에서 수생 종 특히, 어류를 중심으로 장벽의 영향을 분석하는 데 중점을 두고 진행되어 왔다. 하천 네트워크 규모에서 다수의 장벽 설치에 대한 누적 효과를 분석한 사례는 거의 없으며, 서식지 및 수생태계 연결과 관련하여, 하천 시스템의 네트워크 규모에서 속성을 설명하고 정량화하는 도구 역시 찾아보기 어렵다. 본 연구에서는 하천 네트워크 내의 종적 방향의 연결성을 정량화하기 위한 방법으로 Cote 등(2009)이 제시한 DCI(Dendritic Connectivity Index) 지표를 이용하였다. 수계 연속성 지표(DCI)는 하천 수계 내의 종적 연속성 평가를 목적으로 횡단구조물의 개소수와 위치, 어류의 이동률을 누적하여 정량화한 방법으로써, 구조물 단위 평가가 아닌 하천 단위 평가 방법이다. 곡성천과 삼척오십천을 대상으로 국가어도정보시스템 및 항공사진을 통해 구축한 구조물의 개소수와 위치정보를 이용하여 시계열 DCI를 산정하였다. 그리고 2차 조사에 걸쳐 횡단구조물 현황 및 수리 특성, 어류현황 및 이동특성 조사 및 분석결과를 DCI에 반영하여 DCIm을 산정하였다. 곡성천의 경우 현재(2018년) DCI 결과는 5.63%이며, 어류 이동률 적용 결과 DCIm은 6.29%로 산정되었고, 약 11.7% 증가하는 것으로 나타났다. 삼척오십천의 현재(2018년) DCI 결과는 9.78%이며, 어류 이동률 적용결과 DCIm은 10.34%로 산정되었고, 약 5.7% 증가하는 것으로 나타났다. 향후 하천 내 수생태계의 연속성을 확보하기 위해서는 우선적으로 하천 수생태계 훼손, 단절, 연속을 효과적으로 비교·평가할 수 있으며, 이를 통해 개선사업의 우순순위 등 의사결정을 위한 방법론의 개발이 필요하다.