불순물 첨가 BGO 섬광체 단결정의 육성과 열형광 특성

김성철,김중환,김종일,정중현,도시홍,김기동,이대원 동의대학교 기초과학연구소 1996 基礎科學硏究論文集 Vol.6 No.1

Eu or Fe doped BGO scintillation crystals were grown by Czochralski method. In order to get information about traps in the grown BGO crystals, we measured trap parameters including activation energy, frequency factor and the kinetic order of thermoluminescence, and compared such parameters with thermoluminescent characteristics of pure BGO scintillation crystals. In addition, optical transmittance of the grown BGO crystals was measured.

우리나라 논 관개용 지하수 수질 특성

김진호,조광래,임수정,이경자,경기천,엄미정,김희권,김찬용,이영한,이신찬,윤순강 한국환경농학회 2003 한국환경농학회지 Vol.22 No.4

This study was carried out to evaluate the status of the groundwater quality for paddy fields irrigation in Korea. Water samples were collected at 130 sites throughout the country. Samples were collected at three seasons-April, July and October-in 2000. According to our survey, the groundwater was found to be suitable for irrigation purpose. Average EC was shown 0.286 dS/m. Nitrate-nitrogen and Cl^(-) concentration was 5.6 ㎎/L, 32.95 ㎎/L which satisfied the Korean Standards for Irrigation Water. Nitrate-nitrogen concentration in each province was shown as following orders: Jeju (11.17 ㎎/L) > Chungnam (8.16 ㎎/L) > Gyeongbuk (6.64 ㎎/L) > Gyounggi (5.91 ㎎/L) > Chungnam (4.95 ㎎/L) > Gyeongnam (3.91 mgk) > Jeonbuk (3.50 ㎎/L) > Jeonnam (3.27 ㎎/L) > Gangwon (2.91 ㎎/L). The concentration by sampling seasons were October (6.62 ㎎/L) > July (5.88 mg&) > April (4.78㎎/L). As the soil of Jeju Province is usually derived from volcanic ash soils mainly used for upland drops, it may influence the nitrate-nitrogen concentration of groundwater. The amount of rainfall also influence the water quality. But the COD_(Cr), were shown April (3.17㎎/L) > July (2.91 ㎎/L) > October (2.40 ㎎/L), it is highly related in the basal dose of organic matter fertilizers. This study demonstrated that groundwater quality was suitable for irrigation, but continuous monitoring is recommended for agricultural policy and developing OECD agricultural environment indicators.

특수 언어발달 장애 환아의 임상 및음향음성학적 특성연구

김연희,박세훈,신용일,김찬양,김현기,김정수 大韓再活醫學會 2000 Annals of Rehabilitation Medicine Vol.24 No.1

청각 자극용 전기자극기 개발

허승덕,정동근,김리석,김광년,강명구,김재룡,김기련 한국음성과학회 2004 음성과학 Vol.11 No.3

This paper introduces a development of an electrical stimulator for auditory stimulation. The electrical stimulator is useful in neurotological diagnosis, audiological evaluation, candidate selection for cochlear implantation, optimal device selection and decision making of MAP strategy for severe-to-profound hearing impaired persons. The development was based on sound parameters of auditory brainstem responses and auditory electrophysiological characteristic such as effective firing of auditory nerve and recording evoked potentials during refractory period of neuron. Besides pulse parameter could adjustable by programming for more varied electrical stimulation evoked response audiometry. Using the electrical stimulator, electrical square pulse was applied to promontory, and electrically evoked auditory brainstem response and electrically middle latency response were successfully recorded in cats.

교잡종 찰옥수수에 대한 연구 : Ⅰ. 찰옥수수 "연농×재래" 교잡종의 생육 및 수량특성 Ⅰ. Growth and Yield Characteristics in Waxy Maize Hybrid Yeonnong × Jaerae

이희봉,정재영,최현구,김기훈,김효기,주정일 충남대학교 농업과학연구소 2001 농업과학연구 Vol.28 No.2

재래종 찰옥수수 F₁ 교잡종에 대한 생육 및 수량비교를 위해 충남대학교 농과대학 실험포장에서 육성한 이들 교잡종의 식물학적 특성에 대한 연구 결과는 다음과 같다. 1. 간장은 대조구에 비해 대학찰×재래찰, FR805/1K₃×고령찰이 가장 크게 나타났으나, FR805/1K₃×대학찰, 찰옥 1호에서 대조구와 비슷하게 나타내었다. 2. 착수수는 간장에서와 마찬가지로 대학찰×재래찰, FR805/1K₃×고령찰이 대조구보다 높게 나타났으나 대학찰×재래찰, 찰옥 1호는 비슷하였다. 3. 분얼수는 각 교잡종들간에 큰 차이가 없었다. 4. 이삭의 길이는 대조구에 비해 교잡종들이 거의 2배이상의 크기를 나타내었다. 5. 이삭직경은 FR805/1K₃× 고령찰의 교잡종을 제외하고 대조구와 비슷하게 나타났다. 6. 이삭열수는 Daehakchal×1K₁/LE만이 대조구와 유의성을 나타내고 기타 교잡종은 대조구와 비슷하였다. In order to evaluate the characteristics of growth and yield in F_(1) waxy hybrids using Korean local maize lines, six hybrids including check, Chalok # 1, were planted at the experinental field of e Chungnam National University. Stem and ear heights of Yeonnong × Jaerae and FR805/IK_(3) × Koryong hybrids were higher than the check hybrid. Number of fillers per plant in all hybrids were similar as 0.3 to 0.5 per plant Ear length of waxy hybrids was longer than 15㎝ of check hybrid and ear diameter was also thicker than check except FR805/IK_(3) × Koryong waxy hybrid. A final result, Yeonnong × Jaerae among hybrids was comparatively superior to other hybrids in the test.

축산분뇨 혐기소화 잔재물의 특성 및 초지 적용성 평가

김승민(Seung Min Kim),정웅기(Woong-gi Jung),성용주(Yong Joo Sung),안희권(Hee-Kwon Ahn),김동성(Dong Sung Kim),윤도현(Do-Hyun Yoon),김동섭(Dong-Seop Kim1),정광화(Hwa Gwang Jung) 한국펄프·종이공학회 2014 펄프.종이기술 Vol.46 No.3

풍선 도뇨관을 이용한 식도 둔형 이물제거

김기운,김시영,이종서,김철,정윤석 대한응급의학회 2001 대한응급의학회지 Vol.12 No.4

Background: In most cases of a foreign body in the esophagus, an ENT specialist is consulted, which may be time consuming if not evaluated in a timely fashion. The patients are admitted to the hospital and sent to the operating room, where they are placed under anesthesia and the object is removed by using an esophagoscope. Methods: A prospective randomized trial was conducted during the period from January 1998 to June 2000. All patients presenting to emergency department with blunt objects in the esophagus were included. In one group, with fluoroscopic guidance, a Foley catheter was placed to remove the blunt foreign bodies. And in the other group, we removed them by using the esophagoscpe. We used the t-test for statistical analysis in this study. Results: Total number of patients enrolled in this study was 38.22 patients were enrolled in the Foley Catheter removal group, and the remaining 16 were enrolled in the esophagoscope removal group. The success rate for the Foley catheter was 21/22(95.5%), and that for the esophagoscope was 15/16(93.8%). The average time of removal for the Foley catheter group was 0.70± 0.28 hours while that for the esophagoscope group was 5.96 ± 2.22 hours. One side effect, nonfatal hypoxia, was noted in the Foley catheter removal group. The average cost for the Foley catheter group were 78,800 won(approximately 600 US dollars) while that for the esophagoscope group took 722,800 won(approximately 600 US dollars). Conclusion: In our study, we found that the success rate for removing blunt foreign bodies from the esophagus by using a simple Foley catheter was high, also the Foley catheter was a time saving and cost effective procedure with an excellent safety profile.

CT 스캔 영상재구성과 개인용 컴퓨터를 이용한 영상 재형성과의 비교에 관한 연구

김상준,김은경,정기훈 大韓口腔顎顔面 放射線學會 1994 Imaging Science in Dentistry Vol.24 No.2

Radiographic planning is needed for implant placement in order to determine implant length, jaw bone volume, anatomical stucture nd so on. Radiographic examination includes conventional radiography, conventional tomography and CT scan. The most accurate mesurement can be obtained from CT scan. For the cross-sectional view of mandible, CT scan reconstruction is generally needed. But the cross-sectional view of mandible can be reformed by personal computer. This study was performed to examine the clinical usefulness of reformed image using personal computer in comparison with CT scan reconstructed image. CT axial slices of 4 mandibles of 4 volunteers were used. Digital imaging system was composed of Macintosh Ⅱ ci computer, high resolution Sony XC-77 CCD camera, QuickCapture frame grabber board and "NIH Image" program. Seven reconstructed cross-sectional images within CT machine(CT group) were obtained. And seven reformed cross-sectional images(PC group) after digitization of CT axial slices into the personal computer were obtained. PC group was compared with CT group in the objective and subjective aspects. The results were as follow: 1.Measurement of mandibular height & width in both group showed insignificant difference(p>0.05). 2.Subjective assessment of the mandibular canal in both group showed insignificant difference(p>0.05). 3.Image reformation using personal computer could provide panoramic view, which could not be obtained in CT scan reconstruction.

류머티스 관절염과 골관절염 환자에서 Transforming grwoth factor β의 발현 양상

김채기,윤원찬,송용호,김상경,최정윤 Official Journal of the Korean society for immunol 2001 Immune Network Vol.1 No.3

아크용해에 의해서 제작된 FeCo에 기초한 연자성체의 자기적 성질에 대한 냉간 롤링과 열처리 효과

김정기,한경훈,이상문,정재윤,신경호 한양대학교 자연과학연구소 2001 自然科學論文集 Vol.20 No.-

최대출력 3.5kw인 고주파에 의한 아르곤 플라즈마 분위기에서 제작된 시료인 Fe0.6 Co0.38(BN)0.02의 결정구조와 자기적 성질을 상온에서의 X선 회절과 진동시료자력계를 이용한 자기이력곡선 측정 방법의 의해서 연구하였다. 시료는 수압기로 9.000Nl㎠의 압력을 가하여 (1)알약형태로 제작하여 (2)냉간롤링과 (3)600℃와 800℃로 열처리를 하였다. X선 회절결과는 시료들의 결정구조가 Fe와 동일한 bcc 결정구조이며, 800℃열처리에 의해서 시료 내부에 존재하는 잔류응력이 제거되어 졌음을 보인다. 롤링에 의한 시료 두께 감소율이 증가함에 따라서 포화자화에 잔류자화는 회절선이동과 함께 증가하였고, 이들 값들을 롤링방향에도 의존함을 보았다. 반면 보자력은 임의의 시료두께 감소율(65%) 이상부터 감소하였다. 또한 열처리온도가 증가함에 따라서 잔류자화와 보자력은 선폭의 변화와 함께 감소하지만 포화자화는 열처리온도와 무관하게 거의 일정한 값을 갖는다. 이는 롤링과 열처리효과에 의해서 시료내부에 존재하는 개재물과 잔류응력이 제거되어 자벽이동이 용이해졌음을 의미하며, 또한 롤링에 의해서 동족원자쌍이 생성되어 롤링방향에 평행한 국부 유도자화용이축이 생성되었음을 의미한다. The crystallographic and magnetic properties of Fe0.6 Co0.38(BN)0.02 synthesized by microwave arc-melting with the maximum power of 3.5KW have been studied by the methods of x-ray diffraction and by the magnetic hysteresis using vibrating sample magnetometer at room temperature. The samples were prepared in a form of (1)pellet pressed under the pressure of 9.000Nl㎠ (2)cold rolled and then (3)heat treated at 600℃ and 800℃. The x-ray diffraction patterns show that the crystal structure of the samples are bcc as same as that of Fe with a good uniformity. A residual stress, which exists in the cold rolled sample, is eliminated by the final 800℃ annealing. As the thickness reduction rate of samples by rolling increases, the saturation magnetization and the remanence increase with x-ray diffraction line shift and are related with the rolling direction. On the other hand, the coercivity decreases at a critical thickness reduction rate of 65%. As the heat treatment temperature increases, the remanence and coercivity decrease with line width but saturation magnetization is maintained at approximately a constant value that has nothing to do with heat treatment. This means that a domain wall motion is easy owing to elimination of a residual stress formed parallel to the rolling direction owing to creation of the like-atom pairs across the slip plane by rolling.