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      • 에너지 트랩 單一 電極 세라믹 필터의 주파수 스펙트럼

        宋埈泰,鄭仁永,李鍾德,徐東勳 成均館大學校 科學技術硏究所 1991 論文集 Vol.42 No.1

        The thickness -extensional trapped energy mode vibrations are treated analytically. In each program the solution cinsists of a sum the dominant plate eigensolutions for shoted electrodes in the electroded resgion and for zero surface charge in the unelectroded region. The driven thickness solution is also included in the electroded region in the programs of forced vibrations. Combinations of these solutions for the infinite plate, which satisfy the differance equations and boundary conditions on the major surfaces exactry, are then employed in an appropriate variational principle of the linear piezoelectricity in order to satisfy the remaining boundary conditions at the junction between the electroded and unelectroded regions approximately.

      • 9.5/65/35 PLZT를 이용한 Color filtering 특성에 관한 연구

        宋埈泰,余東勳,李範熙 成均館大學校 科學技術硏究所 1992 論文集 Vol.43 No.1

        In this study 9.5/65/35 PLZT was selected which has the excellent quadratic electro-optic property and slim-loop. It was fabricated by the methods of vacuum hot-pressing and sintering. The electrode of color filter was evaporated using the interdigital type masks. They had the ratio of electrode gaps and the specimen thickness which were 1 : 1, 1.5 : 1, 2 : 1, and 2.5 : 1. Its color filtering characteristics were measured in the range of wavelength 380 to 780[nm] and electric field 0 to 15[kV/cm]. The results shows the relationship between the thickness of specimen, the electrode gap and the maximum RGB transmittance.

      • SCOPUSSCIEKCI등재
      • KCI등재

        타타늄의 열처리 조건에 따른 동전위 양극분극특성 및 표면 미세구조 변화

        주동현,이용렬,정영화,양홍서,박상원,이도재,송호준,박영준 大韓齒科器材學會 2002 대한치과재료학회지 Vol.29 No.2

        The corrosion resistance of metallic implants is essential for successful implant osseointegration. Moreover, the implant surface should have appropriate surface roughness for the attachment of the osteoblast and collagen fibrils. When titanium is exposed to air a thermodynamically very stable oxide film is formed at once. This oxide is very thin and yet it protects the metal from corrosion instantaneously. However, the oxide would not be ideal, and it would be supposed that the state of oxide film would be various by the different conditions when it is formed. The objective of this study was to evaluate the electrochemical properties and surface microstructural changes of titanium after passivation treatment or exposure to high heat (in vacuum or in air). ASTM grade 2 commercially pure titanium (Ti) disks of 10㎜ diameter were wet ground and polished with 240 and 600 grit SiC, and then ultrasonically cleaned with distilled water and ethanol. Cleansed as-received samples (As-R group) were passivated with 30% nitric acid solution at 50℃ for 15 minutes to make the Pas group. The Std-V samples were made by treating the Ti disks in vacuum quartz tube (10^-8 Torr) at 530℃ for 40 min for stress relieving, followed by annealing at 700℃ for 90 min, and then slow cooling to room temperature. The Std-A samples undergo identical procedure as the Std-V group except that it is done in air. For 530℃-V samples, Ti disks were heated at 530℃ for 40 minutes and slow cooled to room temperature. The 1000℃-V samples were produced by heating Std-V specimens again at 1000℃ for 2 hr, followed by cooling to room temperature. 530℃-A and 1000℃-A samples were also prepared. Potentiodynamic anodic polarization measurement, SEM, AFM and XRD analysis were performed to evaluate the effects of the various treatments. The difference in the mean values of E_corr between groups showed statistically significant difference (P<0.05), but that of I_corr did not show significance (P>0.05). When Ti surface was passivated there was a shift of corrosion potential (E_corr) in the noble direction and a lower corrosion current density (I_corr) value. Std-A samples showed most noble E_corr value among the tested groups. 530℃-V samples showed more noble E-corr than other tested groups except Std-A group. 1000℃-V samples showed more noble E-corr than those of Std-V sample. In the case of Std-, 530℃- and 1000℃-groups, -A sub-groups showed better corrosion resistant characteristics than -V sub-groups in regard to E-corr and I_corr values. In the SEM observations, the surfaces of the As-R samples showed only scratch line on smooth surface. In Pas samples, thick oxide layer covered the surface under high magnification observation. 530℃-A samples were covered by oxide granules, and Std-A samples had 25~50 nm-thick acicular oxides. The 1000℃-A samples were covered by coarse oxide crystals with a granule diameter of 0.1~0.6 μm having a gross appearance of milky white color, which was identified by XRD as a rutile. On the other hand, 1000℃-V samples showed an Widmansta¨tten structrue of which the orientation of the lattice is formed along crystallographic planes of the parent crystals. On the AFM observation, 530℃-A samples showed RMS roughness of 79.38 nm which is 5 times rougher than those of the As-R samples. Std-A sample had a roughness of 330.47 nm which is about 20-times rougher than that of the As-R sample. 1000℃-A samples were covered by coarse granular oxides and the roughness were about 0.56 μm. Vacuum sub-group samples showed a more smooth surface than air sub-group samples, and the oxide film was more dense. Due to variability of the surface treatment and heat treatment conditions, the process of the oxide formation seems to be affected thereby making the corrosion properties and surface micro-morphology different. However, more various electrochemical analysis together with surface analysis, and an investigation for the effects of those on the osteoblast cell adhesion and calcium phosphate apposition are needed for the improvement of the osseointegration rates of the titanium implants.

      • KCI등재

        강산 및 강알칼리 음독에서 냉각 용액을 사용한 희석 요법과 중화 요법의 가능성

        이중의,송형곤,김동훈,권운용,곽영호,서길준,윤여규 대한응급의학회 2001 대한응급의학회지 Vol.12 No.3

        Background: There is no effective treatment modality for caustic agent ingestion. Dilution and neutralization are prohibited because of the risk of secondary thermal injury. This experiment is designed to evaluate the amount of dilution and neutralization heat and to gauge the applicability of dilution and neutralization therapy using cold solutions to suppress the peak temperature. Methods: This is an in-vitro chemical experiment. HCl, CH3COOH, NaOH, and NH4OH are selected as representatives of strong and weak acids and strong and weak alkali, respectively. 20℃, 11.6M, 5.8M, and 2.9M solutions of each acid and alkali are made and mixed using a magnetic stirrer at a room air temperature of 28℃. The peak temperature, the duration above 40℃, and the heat amount are measured or calculated. Results: When a 11.6M HCl or NaOH solution is diluted with same amount of water, 32 or 18cal. per mL of HCl or NaOH is produced, respectively. HCl produces a significant peak temperature, but NaOH does not. The lower the concentration, the lower the amount of heat production. 11.6M CH3COOH and NH4OH solutions don't produce dilution heat.11.6M and 5.8M solutions of all acids and alkali produce destructive neutralization heat. However, 2.9M solutions produce neutralization heat which might be controllable. When a 11.6M HCl or NaOH solution is neutralized with a -10℃ 2.9 M NaOH or HCl solution, respectively, the peak temperature produced is below 40℃ and seems to add little thermal damage to viable tissue. Conclusion: Dilution and neutralization with a cold solution in cases of strong acid or alkali ingestion is a promising method to avoid thermal injury.

      • 서울의 Penicillinase Producing Neisseria Gonorrhoeae 발생빈도(1996)

        김재홍,황동규,전재홍,김윤석,김중환,김용준,이창균,임동진,김현수,조창근,김경문,박상훈,전우형,김희성,이호정,차명수,김갑형,김형석,김석우,황지환,박병순,권오상,이민수,송기훈,성소영,이인섭,부태성 대한화학요법학회 1999 대한화학요법학회지 Vol.17 No.2

        Background : In recent years, gonorrhea has been panedemic and remains one of the most commom STDs in the world, especially in developing countries. Objective & Methods: For the detection of a more effective therapeutic regimen and assessing the prevalence of PPNG, we have been trying to study the patients who have visited the VD Clinic of Choong-Ku Public Health Center in Seoul since 1980 by means of the chromogenic cephalosporin method. Results: In 1996, 139 strains of N. gonorrhoeae were isolated, among which 53(39.0%) were PPNG. Conclusion: Our results suggests that after a peak of 74.3% in 1993, the prevalence of PPNG in Seoul is gradually declining.

      • KISE-기초학력검사(KISE-BAAT)개발연구

        박경숙,김계옥,송영준,정동영,정인숙 국립특수교육원 2004 연구보고서 Vol.- No.12

        본 연구는 학교 학습 특히. 국어와 수학에서 부진을 나타내는 아동을 선별 또는 진단하고, 이들이 부진을 나타내는 영역과 수준을 파악하여 이들의 교육계획 수립과 적용에 필요한 정보를 제공할 수 있는 개인용 기초학력 검사(Korea Institute for Special Education-Basic Academic Achievement Tests KISE-BAAT)의 개발을 위해 기초학력의 개념과 기초학력의 구성요인 등을 탐색하여 KISE-BAAT의 구성모형을 개발한 다음, 그 모형을 토대로 검사문항의 성취기준을 설정하고, 그에 따라 제7차 교육과정의 내용을 토대로 범교과적으로 통용할 수 있는 KISE-BAAT의 검사문항을 개발하였다. 본 연구는 유ㆍ초ㆍ중ㆍ고등학교 및 대학교의 학생 1,499명을 대상으로 KISE-BAAT의 예비검사를 실시하고, 그 결과를 토대로 검사문항의 변별도와 양호도 등을 분석하여 최종 검사문항을 선정하였다. 그리고 본 연구는 KISE-BAAT의 표준화를 위해 전국의 유치원, 초등학교와 중학교에 재학중인 5~l4세의 아동 5,977명을 대상으로 검사를 실시하여 규준의 작성 및 해석에 필요한 기초 통계를 산출하였으며, 신뢰도와 타당도를 검증하였다. 본 연구의 결과를 요약하면 다음과 같다. 첫째, 본 연구는 학력을 기초학력 과 심화학력으로 구성 된다고 가정 하여 심화학력에 의 한 학업성취를 제외한 학업성취를 기초학력으로 규정하고, 만 5세부터 14세까지 아동의 기초학력을 측정하는 개인용 기초학력검사인 KISE-BAAT를 개발하였다. KISE-BAAT는 KISE-BAAT(읽기), KISE-BAAT(쓰기), KISE-BAAT(수학)의 3개 검사로 구성되는 복합심리검사(battery)로서 각각의 소검사는 가형과 나형 2종의 동형검사로 구성되어 교육 프로그램의 사전ㆍ사후효과, 일반화 및 전이효과 측정을 용이하게 하며, 백분위수ㆍ환산점수ㆍ학력지수 학년규준의 제시로 아동의 기초학력의 지체 여부와 정도에 대한 진단과 더불어 교육계획의 수립ㆍ시행 및 평가에 활용할 수 있도록 하였다. 따라서 KISE-BAAT는 학교학습의 도구가 되는 읽기ㆍ쓰기ㆍ수학의 기초학력을 종합적으로 측정할 수 있으며, 결과를 다양하게 분석할 수 있는 개인용 기초학력검사라 할 수 있다. 둘째, KISE-BAAT의 신뢰도를 검증한 결과, 동형검사 신뢰도계수는 KISE-BAAT(읽기) 가형과 나형 .82, KISE-BAAT(쓰기) 가형과 나형 .69, KISE-BAAT(수학) 가형과 나형 .89로 나타났고, 반분신뢰도 계수는 KISE-BAAT(읽기) 가형 .93, 나형 .92, KISE-BAAT(쓰기) 가형 .91, 나형 .94, KISE-BAAT(수학) 가형과 나형 모두 .98로 나타났으며, 문항반응이론 신뢰도 계수는 KISE-BAAT(읽기) 가형과 나형 모두 .90, KISE-BAAT(쓰기) 가형 .99, 나형 .96, KISE-BAAT(수학) 가형 .97,나형 .99로 나타났다. 그리고 측정의 표준오차는 KISE-BAAT(읽기) 가형 .76, 나형 .85, KISE-BAAT(쓰기) 가형 .90, 나형 .92, KISE-BAAT(수학) 가형 2.11, 나형 2.32로 나타났으며, 재검사 신뢰도 계수는 KISE-BAAT(읽기) 가형 과 나형 모두 .96, KISE-BAAT(쓰기) 가형 .95, 나형 .96, KISE-BAAT(수학) 가형과 나형 모두 .98로 나타났으며, 문항의 내적 일치도 계수도 KISE-BAAT(읽기) 가형과 나형 모두 .98, KISE-BAAT(쓰기) 가형과 나형도 모두 .98, KISE-BAAT(수학) 가형과 나형 모두 .99로 나타났다. 따라서 KISE-BAAT의 KISE-BAAT(읽기), KISE-BAAT(쓰기), KISE-BAAT(수학) 가형과 나형은 모두 측정학적으로 아동의 기초학력을 측정하는데 있어 일관된 수치와 정보를 제공해 주는 도구라 할 수 있다. 셋째, KISE-BAAT의 타당도를 검증한 결과, KISE-BAAT(읽기) 가형ㆍ나형과 KEDI-기초학습기능점사 읽기Ⅱ의 상관계수는 각각 .50, .56, KISE-BAAT(쓰기) 가형ㆍ나형과 KEDI-기초학습기능검사 읽기Ⅰ의 상관계수는 각각 .68, .67, KEDI -기초학습기능검사 쓰기와 상관계수는 각각 .51, .68, KISE-BAAT(수학) 가형ㆍ나형과 KEDI-기초학습기능검사 셈하기의 상관계수는 각각 .70, .75로 나타났다. KISE-BAAT와 KEDI-기초학습기능검사는 매우 다른 영역과 내용으로 구성되어 있고, 서로 다른 개념을 기초로 제작된 것이나 두 검사간의 상관계수는 비교적 양호한 상태라 할 수 있다. 그리고 구인 타당도의 한 측면을 나타내는 KISE-BAAT 검사영역 상호간 상관계수는 전체적으로 KISE-BAAT(읽기) 가형이 .23에서 .93을, 나형이 .19에서 .91을 범위로 하고 있으며, KISE-BAAT(쓰기) 가형이 .70에서 .95를, 나형이 .73에서 .95을 범위로 하고 있고, KISE-BAAT(수학) 가형이 .81에서 .94를, 나형이 .83에서 .94를 범위로 하고 있다. 따라서 KISE-BAAT는 개발의 과정에서부터 이루어진 내용 타당도의 확보를 위한 노력 등으로 기초학력을 측정하는데 타당한 도구라 할 수 있다. 따라서 본 연구에서 개발한 KISE-BAAT는 아동들의 읽기ㆍ쓰기ㆍ수학 기초학력을 측정하는 신뢰롭고 타당한 개인용 기초학력검사라 할 수 있다. 그러나 KISE-BAAT는 연구 수행상의 제한점과 함께 앞으로 활용의 과정에서 나타나는 문제점을 계속 수정 보완해야 한다. 뿐만 아니라 KISE-BAAT는 문항 편파성 분석 (item bias analysis)과 일반화 가능도 분석에 대한 연구와 더 폭넓은 타당도 분석을 위해 사고력 검사나 다른 학력검사와 공인타당도 분석 등을 연구해야 한다. 그래야만 KISE-BAAT는 아동의 기초학력을 진단 평가하는데 더욱 유용하고 정교한 검사로 발전해 갈 수 있을 것이다. The purpose of this study is to develop a basic academic achievement test battery, KISE-BAAT(Korea Institute for Special Education-Basic Academic Achievement Tests) which provides information about a student's achievement and performance in reading, writing and math. In order to develop the test battery the concept and construct of basic academic achievement were investigated. Subsequently the framework of the test battery was developed, the achievement standards of test items were established and test items were developed based on the current seventh national curriculum. The item tryout of KISE-BAAT was administered to 1,499 students in grades K, 2, 5, 8, 12 and in college. Item difficulty and discrimination data were obtained. Items were selected by reviewing all data available. The national standardization was administered to 5,977 students in grades K through 9. Data obtained from the standardization test used to develop national norms for the test and reliability and validity of the test. The results of the study is as follows. First, KISE-BAAT, a test battery for an individual, consists of three tests of reading, writing and math. Each test has Form A and Form B. KISE-BAAT is used to assess the achievement of an individual student of age 5 through 14. The data can be used for general instruction, remedial instruction and evaluation of an educational program. Second, Several methods were used to estimate the reliability of KISE-BAAT. Alternate-form reliability coefficient of KISE-BAAT(Reading) is .82, KISE-BAAT(writing) .69, KISE-BAAT(Math) .89. As for Split-half Reliability coefficient of each alternate form of KISE-BAAT(Reading) shows .93 and .92. In KISE-BAAT(writing) .91 and .94 are presented. In KISE-BAAT(Math) .98 in common. Item response theory reliability coefficient of each alternate form of KISE-BAAT(Reading) are .98 in common. In KISE-BAAT(writing) .90 and .92 are presented. In KISE-BAAT(Math) .97 and .99 are presented. The standard error of measurement of each alternate form of KISE-BAAT(Reading) is .76 and .85, for KISE-BAAT(writing) .90 and .92 and for KISE-BAAT(Math) 2.11 and 2.32. Test-retest reliability coefficient of each alternate form of KISE-BAAT(Reading) are .96 in common. In KISE-BAAT(writing) .95 and .96 are presented. In KISE-BAAT(Math) .98 is presented in common. Third, the criterion-related validity of KISE-BAAT in terms of the relationship with KEDI-Basic Academic Ability Test was examined. The validity coefficient of each alternate form of KISE-BAAT(Reading) and Reading II of KEDI-Basic Academic Ability Test showed .50 and .56 repectively. The validity coefficient of each alternate form of KISE-BAAT(Writing) and Reading I of KEDI-Basic Academic Ability Test showed .68 and .67 respectively. Reading I of KEDI-Basic Academic Ability Test was matched to KISE-BAAT(Writing) since it has features of writing ability. The validity coefficient of each alternate form of KISE-BAAT(Reading) and Writing of KEDI-Basic Academic Ability Test showed .51 and .68. The validity coefficient of each alternate form of KISE-BAAT(Math) and Computing of KEDI-Basic Academic Ability Test showed .70 and .75. As for intercorrelation coefficents between subtests KISE-BAAT(Reading) range form .23 to .93. In KISE-BAAT(Writing) from .70 to .96 and in KISE-BAAT(Math) from .81 to .94. Based on all the data mentioned above KISE-BAAT can be said a reliable and valid test battery which assess students' ability in reading, writing and math. However, KISE-BAAT should be modified and complemented in order to compensate its own limitations. Future research on item bias analysis and generalizability needs to be done. Criterion-related validity to examine the relationship with other psychological tests or achievement tests also should be done to validate KISE-BAAT further. Case studies and suggestions from test users will also contribute to improve KISE-BAAT.

      • 장티푸스 진단에 있어서 Vi-Indirect Fluorescent Antibody Test의 민감도 및 특이도

        장경희,류동렬,박성하,박병규,이준구,염준섭,최영화,송영구,김현숙,정윤섭,김준명 대한감염학회 1998 감염 Vol.30 No.4

        목 적 : 장티푸스는 체액의 세균배양검사에서 Salmonella typhi의 분리로 확진하지만 조기진단을 위해서는 혈청학적인 검사가 도움이 된다. 저자 등은 1989년 이후 장티푸스진단에 S. typhi의 Vi항원을 이용한 간접형광항체법 (Vi-indirect fluorescent antibody test : Vi-IFAT)을 도입하였다. 이에 지난 7년간의 검사결과를 토대로 Vi-IFAT의 민감도 및 특이도를 규명하고자 하였다. 방 법 : 1989년부터 1996년까지 연세대학교 의과대학 세브란스 병원에 발열을 주소로 내원하여 Vi-IFAT가 의뢰된 환자 중 발열의 원인이 확진된 744명의 환자를 대상으로 하였으며, Vi-IFAT에 있어서 양성반응은 1:64이상으로 하였다. 결 과 : 1) 세균배양검사에서 확진된 장티푸스 환자 178예 중 168예에서 양성반응을 보여 민감도는 94.4%이었다. 항체가는 1:64가 89예, 1:128이 36예, 1:256이 27예, 그리고 1:512가 16예이었다. 위음성이었던 10예의 항체가는 1:32가 7예, 1:16이하가 3예이었다. 2) 발열을 주소로 내원한 환자 중 장티푸스 이외의 다른 질환으로 확진된 566예 중 538예에서 음성반응을 보여 특이도는 95.1%이었다. 항체가는 1:32가 117예, 1:16이하가 421예이었다. 위양성이었던 28예의 항체가는 1:64가 23예, 1:128이 5예이었으며, 장티푸스 이외의 살모넬라증이 4예, 요로계감염이 10예, 소화기계감염이 6예, 호흡기 계감염이 5예, 악성 종양이 2예, 그리고 바이러스 감염이 1예이었다. 3) Vi-IFAT 양성인 196예 중에서 장티푸스는 168예로 양성예측율은 85.7%이었으며, Vi-IFAT 음성인 548예 중 장티푸스 이외의 발열질환은 538예로 음성예측율 98.2%이었다. 4) 배양검사와 Widal test 사이의 일치율 (Kappa value)는 0.28로 poor agreement를 보였으며 Vi-IFAT와 Widal test 사이의 Kappa value는 0.74로 good agreement를 보였다. 그러나 배양검사와 Vi-IFAT 사이의 Kappa value는 0.86으로 excellent agreement를 보여 일치율이 가장 높은 검사는 배양검사와 Vi-IFAT라 할 수 있겠다. 5) 장티푸스 환자에 있어서 Vi-IFAT의 양성율은 발열기간이 1중 미만인 환자에서는 68%, 1내지 2주인 환자에서는 89.5%, 2주이상인 환자에서는 100%이었다. 결 론 : Vi 항원을 이용한 간접형광항체법 (Vi-IFAT)은 장티푸스 진단에 높은 민감도 및 특이도를 가지며, 또한 조기진단에 있어서도 임상적으로 유용함을 확인할 수 있었다. Background : Typhoid fever is diagnosed by culture or serological study. The confirmative diagnosis of typhoid fever is made by culture of the causative organism usually from body fluids. Serological test is a supportive diagnositic tool, which is useful for early diagnosis. In Severance Hospital, Vi-indirect foluorescent antibidy test(Vi-IFAT) using the Vi-antigen of Salmonella typhi has been used in the diagnosis of typhoid fever since 1989. We investigated the test results from the past 7 years, in order to clarify the sensitivity and specificity of Vi-IFAT. Methods : A retrospective study was done on patients whose chief complaint was fever and who were tested using Vi-IFAT in the Severance Hospital from 1989 to 1996. The positive value for Vi-IFAT was defined as 1:64 or higher. Results : The sensitivity and specificity of Vi-IFAT for typhoid fever was 94.4% and 95.1%, respectively. The positive and negative predictive values were 85.7% and 98.2% respectively. Positive rates of Vi-IFAT after fever onset increased with time and 68% were positive before the first week. From the first to the second week, 89.5% were positive and after the second week, 100% were positive. Conclusion : Vi-IFAT is not only a valuable serologic test for the diagnosis of typhoid fever, but also useful in the early diagnosis of the disease.

      • 방전관용 전극개발 및 특성에 관한 연구

        안성환,황동원,최준영,송시준,전용우,박원주,이광식 영남대학교 공업기술연구소 2001 工業技術硏究所論文集 Vol.29 No.1

        This paper describes the development of sputtered tungsten electrode for discharge tube by making use of Sputtering method using plasma. The Xe discharge tube was designed and fabricated by using sputtered tungsten electrode, and the ICCD(Intensified Charged Coupled Device) and monochromator were used in order to observe the discharge image distribution and to measure the signal intensity. As a result, the emission light form the electrode was spreaded almost uniformly over a wide wavelength band, and the discharge image distribution and the signal intensity show quite a uniform distribution. The emission light from the Xe discharge tube was peaked at 488[nm] and 648[nm].

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