Sol-Gel방법에 의해서 성장시킨PbTiO₃박막의 결정화와 물리적 성질

구영진,강민진,정원태,김태현,김상수 昌原大學校 基礎科學硏究所 2000 基礎科學硏究所論文集 Vol.12 No.-

Ferroelectric PbTiO3 thin films coated on SiO2/Si(100) and ITO glass substrates were prepared by sol-gel processing of metal alkoxide solutions and solvents. The use of sol-gel method for preparing various functional films makes it possible for the homogeneous distribution of elements at the molecular level, precise composition control, lower temperature synthesis, large surface coating and high optical quality. First of all, the XRD investigation shows that perovskite phase of polycrystalline PbTiO3 was formed by four times coating of the concentrated solution and by the heat treatment over 500, 600℃(O2 gas and air) and over 10, 20, 30 min. Surfaces of thin films were crack-free and uniform and the average grain size investigated by SEM was 0.25∼1.00 ㎛. Dielectric constant of PbTiO3/ITO glass thin film were 380 ∼ 5.25 in the region of 1 kHz∼ 10 MHz at room temperature(30℃), respectively. From the hysteresis loop of PbTiO3/ITO glass thin film, a remnant polarization of 0.382 μC/cm2 and a coercive filed of 23.85 kV/cm were obtained. At the frequency(5 kHz), C-V measurements of films in MFIS and MFM configurations showed well-behaved C-V characteristics and an injection type hysteresis. The capacitance of flat band(CFB) was 60 pF. The band gap energies of the thin films depend on the assumption of direct or indirect transition. Using one layer structure model, we calculated refractive index, extinction coefficient, absorption coefficient and band gap energy of thin film in the wavelength range of 300 to 800 nm. The band gap energy, refractive index and extinction coefficient at λ = 6325 Å of the PbTiO3 thin film were 3.7 eV, 1.96 and 0.1 respectively.

지속성 외래 복막투석환자에서 발생한 장간막경색증 1예

강동구,이준상,윤재호,장원철,조영일,송종호,전혜정 건국대학교 의과학연구소 2004 건국의과학학술지 Vol.13 No.-

The mesenteric infarction, as a abdominal disease which show acute abdominal pain and almost need to emergency operation, has very high mortality. This mesenteric infarction has been reported very rarely. Also specific clinical manifestations are not clear, therefore initial diagnosis can be missed easily so that patients usually miss their opportunities for adequate treatment. Especially CAPD patients have high mortality because of their rareness and having similar symptoms like CAPD peritonitis. The authors report that the mesenteric infarction was miss-diagnosed to the CAF'D peritonitis with unspecific symptoms.

1982년 경북지방 우량아 선발대회에 참가한 영유아의 성장발육상

이원석,구순모,강덕식,이건수 慶北大學校 醫科大學 1982 慶北醫大誌 Vol.23 No.2

1982년 경북지방 우량아 선발대회에 참가한 영유아(9-24개월) 442명을 대상으로 이들의 각종 신체계측치 및 혈청단백량, 비타민 D 결핍상황을 살펴본 결과 다음과 같은 결론을 얻었다. (1) 체중에 있어서 한국표준치 및 일본평균치와 비교하여 남녀 모두 2.11∼3.19kg 1.25-2.25kg 우위에 있었고 신장 역시 4.29-6.75cm 및 2.46-2.73cm 우위에 있었으며 흉위 및 두위에 있어서도 각 0.75-4.48cm, 1.33-4.04cm 및 6.54-2.17cm, 0.1-1.06cm 씩 우위임이 측정되었다. (2) 피부두께 측정치에서 Triceps skin fold thickness가 홍등의 계측치에 비해 남아는 0.40-1.48mm, 여아는 1.41-1.93mm, scapular thickness에서는 남아 2.29-2.44mm, 여아가 2.35-2.83mm우위에 있었다. (3) 상완둘레는 홍등의 계측치보다 남아 2.53-2.77cm, 여아 2.19-2.43cm 우위에 있었다. (4) Hand refractometer를 사용하여 측정한 혈청단백량은 남아평균 7.00gm% 여아 7.08gm%로서 연령별 차이는 없었다. (5) kaup지수 20이상은 남아에서 7.8% 여아 6.3%로 나타났다 (6) 수유방법에서는 모유영양이 가장 많아 50.2%였으며 다음이 혼합, 인공영양의 순서였다. (7) 이유시기는 56.6%가 4-6개월에 시작하여 1년이내에 대부분(98.8%)이 시작한 것으로 나타났다. (8) 헤마토크맅치가 33미만인 빈혈환아는 4.75%였고 약 1/3에서 철분투여가 이루어졌으며 빈혈은 철분투여군에서 3.4%, 비투여군에서 5.4% 발생하였다. (9) 약 1/4에서 비타민 D가 투여되었으며 D 부족증상은 12.7%에서 발견되었고 이들의 대부분이 (80%) 이전에 비타민 D 공급을 받지 못했으며 투여군에서 10%, 비투여군에서 13.6% 나타났다. (10) 본 조사군에서는 과거 5년간에 비해 성장발육(체중, 신장, 흉위, 두위, 상완둘레, 피부두께은 큰 차이가 없으나 비만정도, 빈혈, 비타민 D 부족증상은 많은 감소를 보였다. Authors have conducted a study on 442 infants participated in Kyungpook regional wellbaby contest, held in 1982. After through investigation of several parameters including physical growth (body weight, height, chest and head circumferences), nutritional status (Kaup index, serum protein, hematocrit and signs of vitamin C deficiency), and feeding history, along with comparing this with data obtaind from past 5 years (1976-1980), the following results were obtained. Comparing their body weight, height, chest and head circumferences with Korean children's growth standard(K.S.) and Japanese children's growth standard(J.S.), their body weight were superior to those of K.S(2.11-3.19kg) and J.S(1.25-2.25kg), their height superior to those of K.S(4.29-6.75cm) and J.S(2.46-2.73cm) but no remarkable diference between these data and those obtained from past 5 years. Triceps skin fold thickness and scapular thickness were superior to those of Hong(0.4-1.93mm,2.29-2.83mm), the arm circumference were superior to those of Hong(2.19-2.77mm), too. But no remarkable difference between these data and those obtained from past 5 years were found. Total mean serum protein was 7.0gm% in male infants and 7.08gm% in female infants. Kaup index was over 20 in 7.8% in male infants and 6.3% in female infants. Compared to past 5 years, obesity was found less frequently. Breast milk feeding was the most common form of the infant feeding comparing 50.2%, followed by mixed feeding 29.8%, and bottle feeding in 20%. Weaning was started between 4-6 months of age in 56.6% of infants and the vast majority within 12 months of age (98.9%) About 5% of those infants showed anemia, using the cirteria of anemia as being hematocrit less than 33%. They were found in 3.4% of infants with iron-supplemented group, and 5.4% of infants without iron supplementation. In 12.7% of the infants, there were signs of the vitamin D deficiency including Harrison's groove, rachitic rosary, and pigeon chest. They were found in 10% of infants with vitamin D supplementation and 13.6% of infants without supplementation. Compared to past 5 years, anemia and vitamin D deficiency were found less frequently.

전하 제어법을 이용한 압전 액추에이터의 이력저감

정순종,이대수,송재성,홍원표,강은구,최원종 한국공작기계학회 2005 한국공작기계학회 춘계학술대회논문집 Vol.2005 No.-

This paper presents a method to reduce hysteresis in multilayer ceramic actuator by connecting the actuator with a capacitor in a series circuit. The change in hysteresis with respect to the capacitor was examined. 0.2Pb(Mg_(1/3)Nb_(2/3))O₃-0.8Pb(Zr_(0.475)Ti_(0.525)) O₃ ceramic material was used as a piezoelectric material for the actuator. Displacement of the actuator was measured in a capacitive gap sensor measuring system. In case of inserting a capacitor in a total circuit, hysteresis became dramatically decreased, and then finally the hysteresis value can be reduced below 0.2%. It was found in this present study that reducing the hysteresis in the actuator is dependent upon the characteristics of the capacitor in total circuit and also operating frequency

TRANSLATIONAL ENHANCEMENT OF MAIZE 10kZ IN TRANSGENIC TOBACCO BY THE LEADER SEQUENCE OF TMV

Kang, Hong-Gu,Park, Jae-Won,Kim, Chung-Ho,Kang, Yun-Jung,Choi, Yang-Do Plant Molecular Biology & Biotechnology Research C 1993 Plant molecular biology and biotechnology research Vol.1993 No.

A Novel Body-tied Silicon-On-Insulator(SOI) n-channel Metal-Oxide-Semiconductor Field-Effect Transistor with Grounded Body Electrode

Kang, Won-Gu,Lyu, Jong-Son,Yoo, Hyung-Joun Electronics and Telecommunications Research Instit 1996 ETRI Journal Vol.17 No.4

A novel body-tied silicon-on-insulator(SOI) n-channel metal-oxide-semiconductor field-effect transistor with grounded body electrode named GBSOI nMOSFET has been developed by wafer bonding and etch-back technology. It has no floating body effect such as kink phenomena on the drain current curves, single-transistor latch and drain current overshoot inherent in a normal SOI device with floating body. We have characterized the interface trap density, kink phenomena on the drain current ($I_{DS}-V_{DS}$) curves, substrate resistance effect on the $I_{DS}-V_{DS}$ curves, subthreshold current characteristics and single transistor latch of these transistors. We have confirmed that the GBSOI structure is suitable for high-speed and low-voltage VLSI circuits.

Concurrent chemoradiotherapy for elderly patients with stage III non-small cell lung cancer

Kang, Ki Mun,Jeong, Bae Kwon,Ha, In Bong,Chai, Gyu Young,Lee, Gyeong Won,Kim, Hoon Gu,Kang, Jung Hoon,Lee, Won Seob,Kang, Myoung Hee The Korean Society for Radiation Oncology 2012 Radiation Oncology Journal Vol.30 No.3

Purpose: Combined chemoradiotherapy is standard management for locally advanced non-small cell lung cancer (LA-NSCLC), but standard treatment for elderly patients with LA-NSCLC has not been confirmed yet. We evaluated the feasibility and efficacy of concurrent chemoradiotherapy (CCRT) for elderly patients with LA-NSCLC. Materials and Methods: Among patients older than 65 years with LA-NSCLC, 36 patients, who underwent CCRT were retrospectively analyzed. Chemotherapy was administered 3-5 times with 4 weeks interval during radiotherapy. Thoracic radiotherapy was delivered to the primary mass and regional lymph nodes. Total dose of 54-59.4 Gy (median, 59.4 Gy) in daily 1.8 Gy fractions and 5 fractions per week. Results: Regarding the response to treatment, complete response, partial response, and no response were shown in 16.7%, 66.7%, and 13.9%, respectively. The 1- and 2-year overall survival (OS) rates were 58.2% and 31.2%, respectively, and the median survival was 15 months. The 1- and 2-year progression-free survivals (PFS) were 41.2% and 19.5%, respectively, and the median PFS was 10 months. Regarding to the toxicity developed after CCRT, pneumonitis and esophagitis with grade 3 or higher were observed in 13.9% (5 patients) and 11.1% (4 patients), respectively. Treatment-related death was not observed. Conclusion: The treatment-related toxicity as esophagitis and pneumonitis were noticeably lower when was compared with the previously reported results, and the survival rate was higher than radiotherapy alone. The results indicate that CCRT is an effective in terms of survival and treatment related toxicity for elderly patients over 65 years old with LA-NSCLC.

NUTRITIONAL QUALITY IMPROVEMENT OF SOYBEAN SEED STORAGE PROTEIN BY GENE MANIPULATION

Kang, Hong-Gu,Lee, Min-Gyu,Park, Jee-Won,Kang, Yun-Jung,Kim, Chung-Ho,Choi, Yang-Do Gyeongsang National University Chinju, Korea 1992 Plant molecular biology and biotechnology research Vol.1992 No.

Environmental exposure of heavy metal (lead and cadmium) and hearing loss

Gu Hyeok Kang,Jun Young Uhm,Young Gon Choi,Eun Kye Kang,Soo Young Kim,Won Oh Choo,Seong Sil Chang 대한직업환경의학회 2018 대한직업환경의학회지 Vol.30 No.-

Background: Lead and cadmium have been identified as risk factors for hearing loss in animal studies, but largescale studies targeting the general human population are rare. This study was conducted to investigate the link between heavy metal concentrations in blood and hearing impairment, using a national population-based survey. Methods: The study participants comprised 6409 Koreans aged 20 or older, who were included in the Fifth and Sixth Korea National Health and Nutrition Examination Surveys (KNHANES 2010–2013). Hearing impairment was categorized into two types, low- and high-frequency hearing impairment, using pure tone audiometry. Lowfrequency hearing impairment was defined as having a binaural average of hearing thresholds for 0.5, 1, and 2 kHz exceeding 25 dB, and high-frequency hearing impairment was defined as having a binaural average of hearing thresholds for 3, 4, and 6 kHz exceeding 25 dB. The blood levels of heavy metals (lead and cadmium) were classified into quartiles. Cross-sectional association between hearing impairment and the level of heavy metals (lead and cadmium) was examined in both sexes. Multivariate logistic regression was used to obtain adjusted odds ratios (ORs) and 95% confidence intervals (CIs). Results: Among men, the prevalence of low- and high- frequency hearing impairment was 13.9% and 46.7%, respectively, which was higher than the prevalence among women (11.8% and 27.0%, respectively). Regarding lead, the adjusted OR of high-frequency hearing impairment for the highest blood level group versus the lowest group was significant in both men (OR = 1.629, 95% CI = 1.161-2.287) and women (OR = 1.502, 95% CI = 1.027-2.196), after adjusting for age, body mass index, education, smoking, alcohol consumption, exercise, diagnosis of diabetes mellitus, hypertension, and noise exposure (occupational, loud, firearm noises). No links were found between blood lead levels and low-frequency hearing impairment, or between blood cadmium levels and low- or high-frequency hearing impairment in either sex. Conclusions: The present study findings suggest that even exposure to low-level lead is a risk factor for highfrequency hearing loss. A prospective epidemiologic study should be conducted to identify the causal relationship between human health and exposure to heavy metals, and efforts to reduce heavy metal exposure in the general population should continue.

INTERFACE TRAP DENSITY OF A NOVEL BODY-TIED SOI nMOSFET BY WAFER BONDING

Kang,Won Gu,Lyu,Jong Son,Kang,Sang Won,Lee,Kwy Ro,Yoo,Hyung Joun 대한전자공학회 1995 ICVC : International Conference on VLSI and CAD Vol.4 No.1

We have measured the interface trap density of novel body-tied SOI nMOSFET fabricated by wafer bonding and etch-back technology. The novel body-tied SOI nMOSFET has a body connected to a highly doped polysilicon, so that a certain bias can be applied to the SOI body for the measurement of charge pumping current. Measured interface trap density at the gate oxide silicon interface of the novel body-tied SOI nMOSFET was about 3.2 X 10^(10) eV^(-1)cm^(-2), which was somewhat larger than 1.9 X 10^(10) eV^(-1) cm^(-2) of the conventional bulk silicon nMOSFET. This result indicates that damage resulting from the wafer bonding and etch-back was not serious.