접속증가에 따른 ADSL망 트래픽 증가에 대한 연구 : ADSL Network Traffic

노승현,이석환,채덕재,안종근 순천향대학교 부설 산업기술연구소 2001 순천향 산업기술연구소논문집 Vol.7 No.2

With the explosive increace of Internet users, wide installation of fiber optical networks is necessary. However, for various reasons, use of conventional network is still popular as an interim solution to the problems. Among many conventional network technologies to support Internet users, ADSL is one of the most popular one. In this paper we are to analyze the traffic on the network, as the number of simultaneously connected users increase.

지속성 외래 복막투석 환자에서 염증 지표와 고해상도 B 모드 경동맥 초음파 소견의 연관성에 관한 연구

송현용,송영수,안철우,강신욱,최규헌,하성규,이현철,이호영,한대석 대한신장학회 2002 Kidney Research and Clinical Practice Vol.21 No.2

배 경 : 저알부민혈증 및 C-반응 단백(C-reactive protein, CRP)이 증가된 지속성 외래 복막투석 환자의 사망률이 높은 정확한 이유는 밝혀져 않다. 혈액투석 환자에서처럼 복막투석 환자에서 저알부민혈증 및 염증반응이 심혈관계 질환 위험인자 인지 알아보고자 하였다. 방 법: 비당뇨병성 말기 신부전, 지속성 외래 복막투석 환자 93명의 심혈관계 질환 위험인자들과 복막 투과 특성 및 알부민, CRP 등의 염증지표에 따라 고해상도 초음파를 이용한 경동맥내막-중간막 두께, 내막-중간막 면적, 플라크의 유무 등을 단면적으로 비교하였다. 결 과: 복막 투과 특성은 고투과막군 14명, 중간 고투과막군 38명, 중간 저투과막군 31명, 저투과막군 10명으로 각 군간의 경동맥 내막-중간막 두께, 플라크 유무 및 내막-중간막 면적의 차이는 없었다. 기존 관상동맥 질환 환자는 8예(8.6%)로 내막-중간막 두께는 관상동맥 질환이 없는 환자보다 증가되었고(0.79±0.21 vs 0.60±0.11 mm, p<0.05) 플라크 형성은 더 많이 보이나 통계적 유의성은 없었다(75.0 vs 63.5%, p>0.05). 혈청 알부민치와 경동맥 내막-중간막 면적은 역상관관계를 보였다(r=-0.27, p<0.05). 저알부민혈증 환자(혈청 알부민 <3.5 g/dL)는 정상 알부민혈증 환자보다 내막-중간막 두께가 증가되었고(0.67±0.15 vs 0.61±0.12 mm, p<0.05), 플라크도 유의하게 많았다(68.0 vs 55.8%, p<0.05). 혈청 CRP치와 경동맥 내막-중간막 면적은 양의 상관관계가 있었으며(r=0.21, p<0.05) CRP가 높은 환자(≥0.8 mg/dL, n=18)에서플라크가 많이 관찰되었으나(65.8 vs 50.0%, p<0.05) 경동맥 내막-중간막 두께 및 내막-중간막면적은 양군간에 차이가 없었다. 다변량 회귀 분석상 경동맥 내막-중간막 두께에 영향을 미치는 인자는 고령, 높은 CRP, 기존 심혈관계질환, 낮은 혈청 알부민 순이였다. 결 론 : 복막투석 환자에서 고해상도 초음파를 이용한 경동맥 내막-중간막 두께 측정은 심혈관계 질환 유무 예측의 비침습적 검사가 될 수 있고 저알부민혈증 및 높은 CRP과 같은 만성염증 지속상태가 복막투석 환자에서 죽상 동맥 경화증의 발생을 증가시킨다고 가정할 수 있다. Background : Continuous ambulatory peritoneal dialysis(CAPD) patients with low albumin(LA) and signs of inflammation reflected by increased C-reactive protein(CRP) level have an increased mortality, but the mechanism of this phenomenon is not clear yet. Methods : To answer whether LA and inflammation also enhance cardiovascular risk in CAPD patients, we performed cross sectional study measuring carotid artery intima-media thickness(IMT), calculated intima-media area(cIM area) and the presence of plaque by high-resolution B-mode ultrasonography in 93 non-diabetic CAPD patients. Results : Patients with coronary artery disease (CAD, n=8) had significantly increased IMT(0.79± 0.21 mm vs. 0.60±0.11 mm, p<0.05) and higher prevalence of carotid plaques(75.0% vs. 63.5%) compared to the non-CAD patients. Significant inverse correlation was observed between serum albumin (SA) level and cIM area(r=-0.27, p<0.05). Those patients with LA(SA <3.5 g/dL) had significantly increased IMT compared to non-LA patients(0.67±0.15 mm vs 0.61±0.12 mm, p<0.05). Prevalence of carotid plaques was also significantly higher in LA patients (68.0% vs. 55.8%, p<0.05). CRP level revealed a significant positive correlation with cIM area(r=0.21, p< 0.05). Patients with high CRP(≥0.8 mg/dL, n=18) had higher prevalence of carotid plaques (65.8% vs. 50.0%, p<0.05) compared to those patients with CRP <0.8 mg/dL, but IMT and cIMT area were not different. By multivariate logistic regression analysis, old age, high CRP, history of CAD and low SA were the independent risk factors affecting IMT. Conclusion : Our study strongly suggests that low albumin and chronic inflammatory state of CAPD patients could be associated with increasing atherosclerotic cardiovascular disease. (Korean J Nephrol 2002;21(2):285-294)

인천 인현동 호프집 화재 피해자 분석

최정태,안무업,안희철,최영미,정재봉,서정열,유기철,이삼우,박석현,조준휘,김성환,김아진,송근정 대한응급의학회 2001 대한응급의학회지 Vol.12 No.4

Purpose : This study was conducted to develop field triage, transportation, distribution, and prehospital care at a fire disaster by analyzing the victims of the fore that broke out at a bar in Incheon. Method : We analyzed the cases of the victims of a fire in Incheon in Oct. 1999. We determined the primary care hospital, the arrival time, the burn size, the outcome, and the injury type from the medical records, the concerned organ records, and interviews with concerned persons. Result : The total number of victims was 137: 56 prehospital deaths, 1 hospital death, and 80 survivals. The Pearson correlation coefficient between the burn size and the severity was -0.175. There were 121(89.6%) cases of inhalation injury, 59 (43.7%) cases of flame burns, 66 (48.9%) cases of hypoxic brain damage, and 16 (11.9%) cases involving other types of injury. Conclusion : The causes of death of the fire victims were inhalation injury and hypoxic brain damage due to CO poisoning and other toxic inhalants. We propose the use of a simple triage and rapid treatment(START) system and a reassessment the delayed category in fire disasters.

154kV용 활선 안전 경보기 개발에 관한 연구

정민규,조현광,우종수,안창회,서영석,김응태,박창기,오세득 영남대학교 공업기술연구소 2000 工業技術硏究所論文集 Vol.28 No.1

In this report we developed a high voltage alarm for the safety of workers who check and repair the 154kV power line. This high voltage alarm we developed is attached on workers' helmet and alarms automatically in order to let workers know when workers work over the safety distance near 154kV power line. Until now the exact safety distance hasn't been regulated and high voltage alarm we've been using was for the range of 6∼22.9kV power line. We fabricated this high voltage alarm on the basis of electric density and actual measurement of power line. The experimental result was that high voltage alarm at 66kV power line alarmed near 90cm, at 154kV power line alarmed near 160cm from the line. Accordingly, we developed the new high voltage alarm which is operated in the range of 66∼154kV power line.

전압제어형 DC/DC Converter의 평균 모델을 위한 Duty Cycle 모델

홍성수,사공석진,안현식 국민대학교 생산기술연구소 2002 공학기술논문집 Vol.25 No.-

The conventional average model for a pulse width modulator employed in a voltage-mode-controlled pulse width modulated converter tends to be numerically unstable when the on-time duty ratio becomes sufficiently small. This paper presents a new average model for a voltage-mode control modulator that is not susceptible to such numerical problems. The validity of the proposed model is confirmed with cycle-by-cycle simulations using an exact discrete-time model.

한국인 상염색체 우성 다낭신 가계에서의 유전자 아형분석

이중건,안규리,황대연,황영환,어현선,채회진,이은주,조종태,김연수,한진석,김성권,이정상 대한신장학회 2000 대한신장학회잡지 Vol.19 No.4

당뇨병 환자에서 혈장 Thrombin-Antithrombin Ⅲ 및 Plasmin-α_2-Plasmin Inhibitor 복합체의 임상적 의의

김경욱,김은숙,정상수,윤수지,박우일,이준희,남수연,안철우,문병수,김경래,차봉수,송영득,임승길,이현철,허갑범 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.25 No.5

연구배경:당뇨병 환자에서 혈액응고 및 섬유소용해 체계의 이상경향이 있어 그 결과로 여러 혈관합병증의 발생위험이 높다는 사실은 널리 알려져 있다. 그 기전은 아직 확실히 밝혀지지 않았으나, 고혈당으로 인한 혈장 단백질들의 비효소성 당화작용이나 산화성 스트레스로 인한 유리 라티칼 작용으로 응고항진이나 섬유소용해 활성의 저하를 유발하는 것으로 생각되고 있다. 최근 응고 및 용해인자와 그 억제자의 복합체들의 증가가 이 상태를 비교적 예민하게 반영한다고 알려져 있다. 방법:본 연구에서는 당뇨병 환자 101명과 정상 대조군 20명에서 혈장내 thrombin­antithrombin complex(TAT)와 plasmin­α₂­plasmin inhibitor complex(PIC)를 측정하여 비교하고, 당뇨병 환자에서 미세혈관 합병증과 대혈관합병증의 유무에 따른 차이와, 이미 혈관 질환의 위험인자로 알려져 있는 인자들간의 상관성을 알아보고자 하였다. 결과:1. 환자의 분포를 살펴보면 혈관합병증이 있는 군은 85명, 혈관합병증이 없는 군은 16명이었고, 평균연령은 각각 57.9±14.1세, 49.9±16.6세로 혈관 합병증이 있는 군에서 더 나이가 많았고, 체질량지수는 23.2±3.4㎏/㎡, 24.1±3.4㎏/㎡로 두 군간 유의한 차이는 없었다. 또 두 군간의 혈압 및 HbA1c, 공복혈당 및 인슐린과 C­peptide, 총 콜레스테롤, 중성지방, HDL­콜레스테롤, Lp⒜는 유의한 차이가 없었고, 미세혈관합병증이 있는 군에서 당뇨병의 유병기간이 길었다. 2. TAT 및 PIC의 농도는 정상 대조군에서는 2.8±1.2 ng/mL, 240.4±69.7 ng/mL이었고, 당뇨병 환자군에서는 9.5±22.6 ng/mL, 472.2±258.7 ng/mL이었다. TAT와 PIC 모두 당뇨병 환자군에서 정상 대조군에 비해 유의하게 증가되어 있었고(p<0.001), TAT/PIC ratio는 두 군간 차이가 없었다. 3. 당뇨병 환자의 혈관합병증에 따른 TAT 및 PIC, fibrinogen 농도는 합병증이 없는 군은 각각 4.1±2.4ng/mL, 362.2±272.0ng/mL, 322.7±102.4mg/mL으로 PIC와 fibrinogen의 증가를 보였으나, 연령을 보정한 후에는 통계학적 유의성은 없었다. 또 대혈관 합병증군에서는 각각 6.0±4.9 ng/mL, 507.4±321.6 ng/mL, 427.1±194.7 mg/dL이었으며 미세·대혈관 합병증군에서는 10.4±6.4 ng/mL, 484.8±269.7 ng/mL, 388.4±132.4 mg/dL으로 TAT의 증가를 보였으나 역시 연령을 보정한 후에는 통계학적 유의성은 없었다. 4. 미세혈관합병증군에서 HbA1c(>8%)가 높은 군의 PIC 농도가 유의하게 높았고(p=0.049), 대혈관합병증군에서 HbA1c(>8%)가 높은 군의 총 콜레스테롤 농도가 유의하게 높았다(p=0.042). 5. 총 당뇨병 환자군에서 PIC는 fibrinogen과 HbA1c와 양의 상관관계를, BMI와 음의 상관관계를 보였으며(r=0.47, 0.31,-0.25), 혈관 합병증이 없는 당뇨병 환자군에서만 TAT는 HbA1c와 양의 상관관계를 보였다(r=0.67). 결론:이상의 결과에서 혈장 TAT 및 PIC 농도는 당뇨병 환자에서 정상 대조군에 비해 의미있게 증가되어 있었고, 당뇨병 환자군에서는 연령의 증가와 유병기간이 혈액응고항진 및 용해의 장애에 큰 역할을 함을 알 수 있었으며, 총 당뇨병 환자군에 PIC와 HbA1c와 양의 상관관계를, BMI와 음의 상관관계를 보였으며 혈관 합병증이 없는 당뇨병 환자군에서만 TAT는 HbA1c와 양의 상관관계를 보였다. 따라서 당뇨병 환자에서 혈액응고 및 용해의 장애가 동반되어 있다고 볼 수 있으며, 혈장 TAT 및 PIC는 혈관합병증으로의 진행을 예측하는 지표로서 유용하리라 생각된다. 또 혈당조절정도와 상관성이 있으므로 혈당조절후에 추적검사를 시행하여 합병증의 예방이 가능한지 추후 연구가 필요하리라 생각된다. Background : Abnormality of coagulation and fibrinolystic system is known as a predisposing factor of vascular complication in diabetes. Although the pathogenesis is not well known, non-enzymatic glycation reaction and the increase in production of free radicals due to an increased oxidative stress may be linked to the hypercoagulibility and hypofibrinolytic activity. As indices of abnormality in coagulation and firinolysis in peripheral blood, plasma thrombin-antithrombin Ⅲ complex (TAT) and plasmin-α_2-plasmin inhibitor complex (PIC) were measured. The purpose of this study was to clarify whether hypercoagulability exists in diabetic patients with or without vascular complication. Methods : In our study, we measured plasma thrombin-antithrombin Ⅲ compelx (TAT) and plasmin-α_2-plasmin inhibit or complex (PIC) in 101 diabetic subjects and 20 controls. Comparing TAT and PIC levels in diabetic microvascular complication group, diabetic macrovascular complication group and controls, we examined correlation between risk factors associated with diabetic vascular complication. Results : 1. The group with diabetic vascular complication was older than group without complication. There was no significant difference in BMI, blood pressure, HbA_ic, blood sugar level, insulin, C-peptide, serum creatinine, total cholesterol, triglyceride, HDL-cholesterol, Lp (a) between two groups. The group with diabetic microvascular complication had longer duration of diabetes. 2. Concentration of TAT and PIC were 2.8±1.2 ng/ mL, 240.4±69.7 ng/ mL in controls and 9.5±22.6 ng/ mL, 472.2±258.7 ng/ mL in diabetic patients, respectively. TAT and PIC were significantly higher in diabetic patients than in control (p<0.001). But TAT/PIC ratio was no significant difference between two groups. 3. In diabetic patients, concentration of TAT and PIC and fibrinogen were respectively 4.1±2.4 ng/ mL, 362.2±272.0 ng/ mL, 322.7±102.4 mg/ dL in group without vascular complication and 5.3±4.1 ng/ mL, 529.5±258.7 ng/ mL, 374.9±106.2 mg/ dL in group with microvascular complication, which group had increase in PIC and Fibrinogen but no significance after correction of age. Concentration of TAT and PIC and Fibrinogen were 60.±4.9 ng/ mL, 507.4±321.6 ng/ mL, 427.1±194.7 mg/ dL in macrovascular complication, and 10.4±6.7 mg/ mL, 484.8±269.7 ng/ mL, 388.4±132.4 mg/ dL in combined vascular complication which group showed increase of TAT but also had no significant increase after correction of age. 4. In diabetic microvascular complication patients, group of high HbA_1c (>8%) (p=0.049) had significant high PIC concentration. In diabetic macrovascular complication patients, group of high HbA_1c (>8%) (p=0.042) had significant high total cholesterol concentration. 5. In all diabetic patients, PIC was positively correlated with fibrinogen and HbA_1c and negatively correlated BMI (r=0.47, 0.31, -0.25). Only in daibetic patients without angiopathy, TAT was positively correlated with HbA_1c (r=0.67). Conclusion : In this study, plasma TAT and PIC concentration significantly increased in diabetic patients compared with controls, and PIC was increased in group with microvascular complication, TAT were increased in group with combined micro macrovascular complication. However, there was no significance relationship existed when correctinf for age. PIC was correlated with HbA_1c. TAT was correlated with HbA_1c only in the group without angiopathy. Abnormality of coagulation and fibrinolysis were combined in diabetes, plasma TAT and PIC can be used as an index of vascular complication. Also we found the correlation with the degree of the blood glucose control. Therefore we need follow up study for the possibility of prevention of vascular complication after controlling the blood glucose to age-matched patients (J Kor Diaabetes Asso 25:354~363, 2001).

대구 성서지역 악취 민원발생일의 기상학적 특성

김해동,구현숙,정우식,최성우,안지숙,박명희 한국환경과학회 2003 한국환경과학회지 Vol.12 No.10

We studied the relationship between a civil affair occurrence of bad smell and meteorological conditions around Seongseo district for recent 2 years. The results were as follows; (1) The civil affair occurrence days of bad smell were concentrated from May to August. (2) Daily mean temperatures were mostly 20~28℃ and daily mean relative humidities were 60~80%. (3) Wind speeds were mostly less than 2m/s(75%). and wind directions were southerly winds(50%). It was hardly occurred for relatively well-ventilated conditions in cases of wind speeds 2m/s over. And the Lagrangian particle dispersion model were used to figure out the transport route in a civil affairoccurrence days of bad smell. It was found that the south-western winds transported the bad smelling materials from Jungni-dong(the place of source) to the housing complex located along a piedmont district.

녹동균 세포외막 단백질 백신 CFC-1-101의 안정성 및 면역원성 검토 : 임상 제 Ⅰ/Ⅱa상 시험

장인진,김익상,유경상,임동석,김형기,신상구,장우현,박완제,이나경,정상보,안동호,조양제,안보영,이윤하,김영지,남성우,김현수 대한감염학회 1998 감염 Vol.30 No.3

목적 : 제일제당에서는 녹농균의 세포외막 단밸질을 유효성분으로 하는 백신인 CFC-101을 개발하였으며, 동물시험에서 이 백신의 안전성과 유효성을 입증하였다. 본 연구에서는 이 녹농균 백신의 인체에 대한 안전성과 면역원성을 평가하는 동시에 인체 접종시의 최적 투여 용량을 결정하기 위하여 제 I/Ⅱa상 임상시험을 수행하였다. 방법 : 건강한 성인 남자를 피험자로 선별하여 각 용량군에 백신투여자 6명, 위약투여자 2명을 배정하였다. 백신 투여군은 0.25mg, 0.5mg 또는 1.0mg 용량의 녹농균 백신을 7일 간격으로 3회에 걸쳐 근육주사 하였으며, 위약 투여군에게는 세포외막 단백질을 제외한 동일한 성분을 투여하였다. 백신접종 후 국소적 또는 전신적인 반응의 발생여부를 관찰하고, 혈액시료를 체취하여 백신의 역가와 유효성을 검정하였다. 결과 : 녹농균 백신 CFC-101은 모든 접종자에서 양호한 내약성을 보였다. 또한 0.5mg 과 1.0mg 백신 투여군에서는 100%의 항체양전율을 나타내었다. 생성된 항체는 녹농균 세포외막단백질에 특이성을 보였고, 녹농균 감염에 대해 방어효능이 있었다. 결론 : 이와같은 결과로부터 이 녹농균 백신은 인체에 안전하게 투여할 수 있으며, 높은 항체 생성능으로 감염방어 효능을 보이고 0.5mg과 1.0mg이 최적용량인 것으로 판단되었다. Background : We developed a Pseudomonas aeruginosa outer membrane protein(OMP) vaccine CFC-101, and the prophylactic efficacy of which has been demonstrated in animal models. In order to evaluate the safety and immunogenicity of the P. aeruginosa vaccine, we carried out a phase I/Ⅱa clinical trial in healthy male volunteers. Methods : Groups of eight volunteers, including two placebo subjects, were vaccinated intramuscularly with three doses of 0.25, 0.5 or 1.0 mg of the vaccine at one week intervals. Sings of systemic and local reactions observed after vaccination were recorded for each vaccinee for 5 days. Physical examinations were performed on days 0, 1, 7, 8, 14, 15, 21, and 42, and clinical laboratory tests were done on days 0, 3, and 21. Blood samples for assay of serum antibody levels were obtained up to 42 days after the first vaccination. Results : The vaccine was generally well tolerated by all vaccinees, showing no significant side effects. In the three dosage groups, all vaccinees, except one receiving the 0.25 mg dose, showed significant elevation in serum IgG antibody titers against the vaccine proteins, indicating 100% seroconversion in 0.5 and 1.0 mg groups. The human antibodies induced by the vaccine were specific for P. aeruginosa OMPs, as confirmed by western blot analysis and immunoprecipitation assays. The capacity of the human antisera to enhance opsonophagocytic killing activity by polymorphonuclear leukocytes and to confer protection against P. aeruginosa infections indicates that the antibodies elicited by the vaccine have protective efficacy. Conclusion : We conclude that the P. aeruginosa OMP vaccine is safe and effective for human use and its optimal dose to be 0.5 or 1.0 mg.

Elongation Habit of Mesocotyl and Coleoptile in a Weedy Rice with High Emergence Ability in Direct-Seeding on Dry Paddy Field

Suk-Hyun Ahn,So-Hee Shin,Min-Ho Wang,Nam-Jin Chung 한국작물학회 2010 한국작물학회 학술발표대회 논문집 Vol.2010 No.04

Direct-seeding method on dry paddy soil could make rice farming large-scale cultivation and cost-saving, but it has still some problems on poor seedling establishment caused by low temperature and varying sowing depth. This research was carried out to identify weedy rice genetic resources that may help to poor seedling establishment in direct-seeded rice on dry paddy soil in temperate region. The genetic resources screened in this study were 128 accessions that consist of 92 japonica weedy rices, 24 indica weedy rices, and 12 Korean bred cultivars.The weedy rices on average have very superior abilities to emerge form depth than cultivated rice. The germplasm showed that the coleoptile or/and mesocotyl lengths were positively correlated with emergence rate to a high degree. Among the germplasm, WD-3, a japonica weedy rice, evidenced the highest level of emergence with the longest coleoptile and mesocotyl elongation. The emergence ability of WD-3 depending on the burial depth under low temperature condition was confirmed in both the phytotron and the field conditions. WD-3 showed 100% of emergence rate until a burial deptho f 7 cm in the dry soil in the phytotron, and 76.2 % of very high emergence rate in the total layer of paddy field where the seeds were sown from the surface to 10 cm depth. In the emerged plants in the field, the mesocotyl elongation increased with increasing burial depth in a logarithmic fashion, and the coleoptile extension increased exponentially. The total elongation lengths of the mesocotyl and coleoptile were similar with a plant burial depth, which indicated that they could induce the safe emergence of the main leaf of the seedling from the soil to thesurface. Conclusively, the elongation habit of mesocotyl and coleoptile of WD-3 could be one of the important characteristics to develop direct-seeding cultivars.