진공열간가압성형 (VHP) 법 및 압출로 제조한 SiCp/Al 및 SiCp/2024Al 복합재료의 동적탄성계수와 감쇄능 (내부마찰) : 금속기 복합재료의 동적탄성계수 및 감쇄능 측정

김영만,조기현,이경민,홍성길 대한금속재료학회(대한금속학회) 1999 대한금속·재료학회지 Vol.37 No.9

To shorten the processes of MMC fabrication, a number of techniques are being studied. In this study, a new process for MMC's fabrication was developed utilizing vacuum hot pressing and subsequent extrusion. MMC's with pure Al and 2024Al matrices reinforced with various volume fractions of SiC particulates were produced at 400℃ by vacuum hot pressing(VHP), followed by direct extrusion with extrusion ratios of 10:1 at 480℃ at constant ram speed of 2㎜/sec. The effects of extrusion pressure and relative density according to the volume fractions of the reinforcement were compared with the resultant metallurgical microstructures. Young's moduli of the manufactured composites were measured by the sonic resonance method, damping capacity by free decay method. Measured Young's moduli of the composites at room temperature were compared with the predictions based on Rule of Mixtures, Halpin-Tsai and Mean-field models. Measured Young's moduli of the composites are in good agreement with the predictions based on Mean-field model. The composites reinforced with finer particles showed higher damping capacity under the same amount of SiC reinforcement.

인터넷 중독 청소년들의 정신병리 및 대처 방식

안영균(Young Kyun Ahn),신영철(Young Chul Shin),고복자(Bok Ja Koh),심진현(Jin Hyun Shim),김범조(Bum Jo Kim),이승민(Seung Min Lee),이길홍(Kil Hong Lee) 한국중독정신의학회 2005 중독정신의학 Vol.9 No.1

This study was conducted to investigate the differences in psychopathology and coping strategies among internet addictors, over users and non addictors in high school students. Subjects were 273 high school students in Seoul city. Self rating questionnaires included demographic data, Young’s Internet Addiction Scale, SCL-90-R, Beck Depression Inventory, Spielberger State-Trait Anxiety Inventory, and The Way of Coping Strategy. Subjects were classified into 3 groups (addiction, over use, non addiction) by Internet Addiction Scale score. Prevalence of internet addiction was 4.3% and male adolescents were more addictive than female. Students who were mainly involved with internet chatting or game showed higher internet addiction score. The addiction group and over use group showed higher level of somatization, obsession, interpersonal sensitivity, depression, anxiety, hostility, and paranoia than non-addicted group. Addiction group and over use group used passive coping strategies more frequently in the stressful situation than nonaddicted group. Also, the regression analysis for finding out causal factors that predicts internet addiction showed that emotion relieving strategy were important variable which predict internet addiction. Interpersonal sensitivity and emotion relieving coping strategy was important to predict addiction. This study showed that problematic internet use was closely associated with psychopathology and psychiatric comorbidity. And high interpersonal sensitivity and emotion relieving coping strategy were related with internet addiction in adolescence.

한국인 인슐린 비의존형 당뇨병 및 이차성 당뇨병 환자에서 글루코키나제 유전자 변이

남재현(Jae Hyun Nam),이현철(Hyun Chul Lee),김연의(Youn Euy Kim),권석호(Suk Ho Kwon),윤용석(Yong Suk Yoon),박석원(Suk Won Park),원영준(Young Jun Won),차봉수(Bong Su Cha),송영득(Young Duk Song),이은직(Eun Jig Lee),임승길(Sung Kil Lim) 대한내과학회 1998 대한내과학회지 Vol.54 No.6

N/A Objectives: Mutations in the glucokinase (GCK) gene are considered a possible cause of maturity-onset diabetes of the young. The purpose of this study was to evaluate the contribution of this gene to the development of non insulin dependent diabetes mellitus (NIDDM), gestational diabetes mellitus (GDM) and post-renal transplantation diabetes mellitus (PTDM). Method: Identification of GCK mutation was attempted on 39 NIDDM patients, 2 GDM patients and 58 selected renal allograft recipients with PTDM and 45 normal controls. The exons in the GCK gene were examined by polymerase chain reaction (PCR), followed by analysis of single-stranded DNA conformational polymorphism (SSCP). The abnormal bands were also confirmed by DNA sequencing analysis. The exons of affected family members were also investigated for mutations of the GCK gene. Results: Two of the 58 PTDM patients (3.4%) were found to have CKK mutations. One had the mutation on exon 5 and the other on intron 7. One control subject had the mutation on intmn 9. The mutation of exon 5 was identified as a substitution of CCT (proline) for CTT (leucine) at codon 164, which has not ever reported before. The family members of the PFDM patient with mutation of exon 5 were analyzed by PCR followed by SSCP, and two of them revealed the same mutation. The abnormal band on the SSCP analysis of exon 7 was identified as the insertion of base C/T at the 39th nucleotide in intron 7. Two family members of this patients also had same band on SSCP. The one mutation of 45 normal controls was CT located at the 8th nucleotide in intron 9, which was a common polymorphism. Conclusion: We found GCK mutations in subjects with PTDM and we speculate that these mutations may be one of the contributing cause of PTDM.

비만증 환자에서 한약제에 의한 체중 감소효과

Oh, Seung-Joon,Jeong, In-Kyung,Kim, Young-Seol,Choi, Young-Kil,Paeng, Jeong-Ryung,Bae, Jung-Hwan,Shin, Hyun-Dae 경희대학교 동서의학연구소 1999 INTERNATIONAL SYMPOSIUM ON EAST-WEST MEDICINE Vol.1999 No.1

Seung-Joon Oh, In-Kyung Jeong, Young-Seol Kim, Young-Kil Choi, Jeong-Ryung Paeng¹, Jung-Hwan Bae and Hyun-Dae Shin²Department of internal Medicine, College Medicine, Endocrine Research Institute¹. Department of Rehabilitation, College of Oriental Medicine², Seoul, korea. Bady Fat Reduction Effects of Red Ginseng Compound Preparation on the Patients with Obesity. Proceedings of International Symposium on East-West Medicine, Seoul. 244-254, 1999.-Obesity can be defined as a metabolic disease due to an increased state of fat tissues caused by an imbalance of calorie intake and use. Recently, in Korea by improvement and westernization of food intake, along with decrease in exercise activities, the prevalence of obesity has increased greatly. Our objectives were to study stability and effects of decrease in body fat by administering red ginseng compound preparation (known to have body fat decreasing effects in laboratory animals) to obesity patients on low calorie diets. Changes in weight and body fat were measured while carrying out calorie-restricted diets on patients for 4 weeks, then administering red ginseng compound preparation for another 4 weeks. The patients were 20 people whose BMI were 25kg/㎡ or over and whose percent body fat was also 30% or over when tested by bioelectrical conductivity. 1. Changes in weight were from 70.04kg(base line) to 67.43kg(after taking red ginseng compound preparation). 2. In similar sense, BMI decreased from 27.12kg/㎡(base line) to 26.56kg/㎡(after dieting), and further to 26.01kg/㎡ (after taking red ginseng compound preparation). The BMI seemed to decrease significantly compared to the baseline after the use of red ginseng compound. 3. Waist hip ratio was changed from 0.8858(base line) to 0.8728, but it was statistically insignificant. 4. The percent body fat was 35,16%(base line), 33.87%(after dieting), and 31.68%(after taking red ginseng compound preparation). 5. Complete blood cell count and blood chemisrty remained unaffected by the administration. 6. In concern to endocrinologic studies, T3 decreased from 118.7 to 98.2ng/dL, and T4 increased from 8.8 to 9.2㎕/ dL. Epinephrine showed a tendency to decreased from 0.27 to 0.25 ng/mL, and norepinephrine increased from 0.39 to 0.44ng/mL. 7. Leptin was not changed. 8. Some patients complained adverse effects; constipation(5 patients, may be due to diet therapy), fatigue (2 patients), pruritus(2 patients), flushing(s patients), dizziness(3 patients) and epigastric discomfort(2 patients). However their symptoms were mild, so medication did not stopped. In conclusion, loss of weight without significant side effects was observed during low calorie diet and red ginseng compound preparation administration. This is thought to be in relation to sympathetic nerve system rather than adrenal gland. Also, further long0term studies should be required, since the observed results were based on short-term changes in weight.

합성 HMT를 이용한 도로 속도 표지판 인식

현영길,도양회 濟州大學校 産業技術硏究所 1998 산업기술연구소논문집 Vol.9 No.1

In this paper. we proposed a method to recognize a speed limit signboard for autonomous road vehicles( ARV's) using the synthetic HMT(hit-miss transform). When images are acquired constantly by a camera of a car while ARV drives. it is difficult to detect the signboard in an instant. So. we set a limited range of distance between the camera and the signboard to have time enough to detect the signboard. However, signboard images which are acquired at each location in the limited range have different shapes each other. So, the synthetic HMT is used to detect each different shaped signboard at one time. Using the synthetic HMT, first signboards are detected and secondly signboard images are extracted. Finally speed limit numer is recognized from the extracted signboard images using the synthetic HMT again. Simulation results shows that the proposed method can be used for detection of signboard and recognition of speed limit in the limited range with only one HMT operation.

胃腸管閉鎖時의 輸液療法

玄偶,李容吉,李尙住 順川鄕病院 1976 順天鄕醫報 Vol.1 No.2

遮光水準이 麥門冬의 生育 및 收量에 미치는 影響

玄京卓,趙南棋,宋昌吉,姜榮吉 濟州大學校亞熱帶農業硏究所 1996 亞熱帶農業硏究 Vol.13 No.-

SummaryFive shading levels (0, 5, 50, 75 and 90%) were investigated for their effects on growth and yield of Liriope platyphylla Wang et Tang. The results obtained were summarized as follows;1. Plant height and leaf length increased with increasing shading levels up to 50% and then decreased with further increasing shading. Leaf width ranging from 0.49 to 0.52cm tended to linearly decrease as shading level was increased. 2. SPAD reading was linearly increased from 56.9 to 69.5 as shading level was increased from 0 to 90%. 3. There was no difference in fresh leaf weight among shading levels. However, fresh weight of roots, tuberous roots, and shoots + roots decreased with increasing shading level. 4. The number of tuberous roots per plant decreased from 21.4 at 0% shading to 11.8 at 90% shading. Dry weight per tuberous root was heaviest (0.4g) at 35% shading and then declined with increasing shading level. 5. Dry tuberous root yield per plant ranged from 6.5g at 0% shading to 3.1g at 90% shading showing linear relationship between yield and shading level. Yield per plant highly correlated wish the number of tuberous roots per plant. 6. The results indicate that growing Liriope platyphylla Wang et Tang under shading has no advantage in Cheju province.

수정 합성 HMT를 이용한 교통표지 분류

현영길,윤종수,도양회 濟州大學校 産業技術硏究所 1999 산업기술연구소논문집 Vol.10 No.1

A classification algorithm of traffic signs using a MSHMT (modified synthetic hit-miss transform) is proposed for the autonomous road vehicles(ARV's). In the case of classification of traffic signs, there are many kinds of signs with intraclass distortions and interclass similarities. The MSHMT provides a good solution with the property of distortion invariant recognition of multiple objects in noisy and cluttered scene. The proposed algorithm of traffic sign classification consists of the phase of sign detection and the phase of symbol recognition. In the phase of sign detection. structuring elements(SEs) are synthesized using only set theory to adapt to simple variations. In the phase of symbol recognition, SEs are synthesized using set theory and SDFkynthetic discriminant function) synthesis method to adapt to complex variations. Based on extensive simulations, it has been shown that the proposed algorithm is efficient for the classification of traffic signs.

수정 합성 HMT를 이용한 교통표지 분류

현영길,윤종수,도양회 濟州大學校工科大學産業技術硏究所 1999 尖端技術硏究所論文集 Vol.10 No.1

A classification algorithm of traffic signs using a MSHMT(modified synthetic hit-miss transform) is proposed for the autonomous road vehicles(ARV's). In the case of classification of traffic signs, there are many kinds of signs with intraclass distortions and interclass similarities. The MSHMT provides a good solution with the property of distortion invariant recognition of multiple objects in noisy and cluttered scene. The proposed algorithm of traffic sign classification consists of the phase of sign detection and the phase of symbol recognition. In the phase of sign detection, structuring elements(SEs) are synthesized using only set theory to adapt to simple variations. In the phase of symbol recognition, SEs are synthesized using set theory and SDF(synthetic discriminant function) synthesis method to adapt to complex variations. Based on extensive simulations, it has been shown that the proposed algorithm is efficient for the classification of traffic signs.

합성 HMT를 이용한 도로 속도 표지판 인식

현영길,도양회 濟州大學校 工科大學 産業技術硏究所 1998 尖端技術硏究所論文集 Vol.9 No.1

In this paper, we proposed a method to recognize a speed limit signboard for autonomous road vehicles(ARV's) using the synthetic HMT(hit-miss transform). When images are acquired constantly by a camera of a car while ARV drives, it is difficult to detect the signboard in an instant. So, we set a limited range of distance between the camera and the signboard to have time enough to detect the signboard. However, signboard images which are acquired at each location in the limited range have different shapes each other. So, the synthetic HMT is used to detect each different shaped signboard at one time. Using the synthetic HMT, first signboards are detected and secondly signboard images are extracted. Finally speed limit numer is recognized from the extracted signboard images using the synthetic HMT again. Simulation results shows that the proposed method can be used for detection of signboard and recognition of speed limit in the limited range with only one HMT operation.