洛東江 河口海城의 식물플랑크톤 極大城 變動에 관한 數値시뮬레이션 : Ⅱ. 식물플랑크톤 극대역 변동의 수치시뮬레이션 Ⅱ. The numerical simulation on variation of phytoplankton maximum region

이대인,김동명,김형철,이석모,박청길 한국환경과학회 2000 한국환경과학회지 Vol.9 No.5

It is very important to interprete and simulate the variation of phytoplankton maximum region for the prediction and control of red tide. This study was composed of two parts, first, the hydrodynamic simulation such as residual current and salinity diffusion, and second, the ecological simulation such as phytoplankton distribution according to freshwater discharge and pollutant loads. Without the Nakdong river discharge, residual current was stagnated in inner side of this estuary, and surface distribution of salinity was over 25psu. On the contrary, with summer mean discharge, freshwater stretched very far outward and some waters flowed into Chinhae Bay through the Kadok channel, and low salinity extended over coastal sea and salinity front occurred. From the result of contributed physical process to phytoplankton biomass, the accumulation was occurred at the west part of this estuary and the Kadok channel with the Nakdong river discharge. When more increased input discharge, the accumulation band was transported to outer side of this estuary. The frequently outbreak of red tide in this area is caused by accumulation of physical processes. The phytoplankton maximum region located inner side of this estuary without the Nakdong river discharge and with mean discharge of winter, but it was moved to outer side when mean discharge of the Nakdong river was increased. The variation of input concentration from the land loads was not largely influenced on phytoplankton biomass and location of maximum region. When discharge was increased, phytoplankton maximum region was transferred to inner side of the Kadok channel. On the other hand, when discharge was decreased, phytoplankton maximum region was transferred to inner side of this estuary and chlorophyll a contents increased to over 20㎍/L. Therefore, if any other conditions are favorable for growth of phytoplankton, decrease of discharge causes to increase of possibility of red tide outbreak.

캔음료중 epichlorohydrin 의분석법에 관한 연구

이광호,곽인신,최재천,전대훈,김형일,강경모,최병희,김귀정,이철원 식품의약품안전청 2001 식품의약품안전청 연보 Vol.5 No.-

캔식품중에 잔류하는 epichlorohydrin을 분석하기 위한 pu링e & trap-Cc/uf통D 분석법을 확립하여 캔의 lacauer 코팅제에서 식품으로 이행되어 잔류하는 epichtorohydfn을 측정하고, 식품유사용매에 의한 용출시험을 통해 일일추정섭취량을 산출하였다. epichlorohydrin의 검량선은 y=0.0006x+0.OO6?(R큰0.9983)의 직선성·라 0.05#ga의 검출한계를 나타내었다. 각종 음료 및 식품유사용매에 일정량의 epichlorohydrin을 첨가한 후 분석하였을 때 회수을은 72~91%였으며, 실제 시판되는 f5건의 캔음료 중 잔류하는 epichlorohydrin을 측정한 결과 모든 캔음료에서 검출한계(0.1#94) 이하였다. 제관업체에서 구입한 modifed epoxy, epoxy phenolic, vinyl organosol, epoxy phenol ester 등의 BADGE(bisphenol A diglycidyt ether)형 에폭시수지로 lacquer 코팅된 식품용 캔에 식품윤사용매인 10% 또는 95% 에탄올을 층L진한 후 90~121'c의 드라이오븐에서 30분~2시간동안 용출시켰을 패 캔의 lacquer 코팅재에서 식품유사용매로 이행되는 epichBorollydirn은 코팅재질, 그리고 가열온도 및 시간에 문관하게 모든 캔에서 검출한계(0.4#ga)이하 였다. 위의 용출결과를 FD.f_의 "Recommendation for Chemistry Data for Indirect Food Additive Petition" 윽 일일추정섭취량 산출법에 적용하여 얻은 epichtorohydrin의 일딜추정 섭 취 량은 0.2r조persorday이하였다. A sensitive ana1?~7tical method based on gas cl)romatogFapy~mass spectrometry with a selected ion monitoring (GE/hfS-Slhf) and the purge-and-trap concentrator ))·asdeveloped for determining ot'epicillorohydrin in canr;ed be)#erages coated with eporl· resin. Thecalibration rurve in the ranre of 0.j ~50nr had'correlation coefficient of 0.9983 and detection limit of 0.Osrga. Recoveries of epichlorohydrin spiked to beverages were in the range of 72 ~91% with detection limits of 0.1 #ga. fn survey of epichlorohydff in twenty commercialcanned beverage samples, epichlorohydrin was not found in all the samples with the detectionlimit of 0.1 r9a. In migration test of various cans coated with BADGE-based coating cans;modifed epoxy, epoxy phenolic, vinyl organosol, epox?· phenol ester were exposed to the foodsimulants of 10% ethanol and 95% ethanol. flfo delectable epichlorohydrin migrated to foodsiHulants was found in aTl the cars with detection Jimit of 0.4 #9/L. Using the miEration data,along uTith the applicstion of food and beverage cans complied with FDA's "Recommendationfor Chemlstry Data f,3r Indirect Food Additive Petition" , the potential dietary exposure toepichlorohydrin was estlmated to be under 0.2rf/person/day.

A2024와 SM45C 마찰용접의 열전달 해석

이상윤,고준빈,명태식,김기길,강형모 大田産業大學校 2001 한밭대학교 논문집 Vol.18 No.-

The heat transfer mechanism initiating the friction welding is examined and a transient three dimensional heat conduction model for the welding of two dissimilar cylindrical metal bars is investigated. The cylindrical metal bars are made of materials made of A2024 and SM45C. Numerical simulations of heat flow are performed using the finite volume method. Respectively, Commercial FLUENT code is used in the heat flow simulation and maximum temperature and distribution of temperature are calculated. Temperature of friction welded joining face is compared with the temperature distribution measured by experiment and numerical simulation. The maximum temperature of friction welded joining face is lower than melting point of A2024-T6 aluminum alloy using insert metal. The temperature distribution of friction welded joining face with insert metal is more uniform than that of without insert metal

토지정보시스템에서 수치지도의 활용에 관한 연구

문형모,이성호 釜山大學校 都市問題硏究所 2003 都市硏究報 Vol.14 No.-

Geography Information System is devided to many details fields Urban Information System, Mlitary Information System etc. Theses detailed fields are connected each other an National Geography Information System. Now Geography Information System is being used in many fields with Urban Information System information of all field is being constructed to network. The purpose of this study is to use digital map for Land Information System. These applicable digital maps have a merit to anlize the regionality when one selected a data structure appropriate to a features of an objective region. GIS software which solve these problems of data structure being developed. The suitability of land use that are devided into urban areas(residential, commercial and industrial) and green areas was analyzed using overlay method by constructed database using digital map. The method and process for grafting digital map on Land Information System were examined and related environmental factors and relative importance among them were investigated on the base of preceding researches.

유세포 측정을 통한 CD34^(+)세포의 정량방법 비교

양형모,서영훈,엄현석,민창기,김희제,정대철,이종욱,진종율,한치화,김춘추,김학주 대한조혈모세포이식학회 1998 대한조혈모세포이식학회지 Vol.3 No.2

본 연구소에서는 현재 CD34^(+) 세포의 정량에 사용되고 있는 4가지 서로 다른 방법을 가지고 골수에 적용하여 그 결과를 비교하였다. 각각의 방법들이 편리한 점과 불리한 점들을 가지고 있었지만, 통계적으로는 유의한 차이를 보이지 않았다. 1) CD34-PE/CD45-FITC 방법13(ISHAGE: International Society of Hematotherapy and Graft Engineering), 2) CD34-PE/CD14-FITC 방법, 3) CD34-PE/CD14-FITC/CD45-PerCP 방법, 4) DNA dye/CD34-PE/CD45-PerCP4(Becton Dickinson) 등을 비교하였으며 그 결과 CD34^(+) 세포의 농도는 다음과 같았다. 1) 0.473±0.345, (%Mean±SD, N=70) 2) 0.663±0.519, (N=20), 3) 0.543±0.381 (N=46), 4) 0.624±0.341, (N=32). 시료로는 여의도 성모병원 카톨릭 조혈모세포이식 센터에서 채혈한 골수를 이용하였다. Four different methods for flow cytometric quantitation of CD34+ cell were compared using bone marrow samples (n=168). Following combination of antibodies were used for the analysis : A) CD45-FITC/CD34-PE (n=70), B) CD14-FITC/CD34-PE (n=20), C) CD14-FITC /CD34-PE /CD45-PerCP(n=46), D) DNA dye/CD34-PE/CD45-PerCP (n=32). Each method showed no significant differences among them (P=0.126, ANOVA test, SPSS Version 7.5). When we compare these methods using same samples (n=12), the P value became 0.832. The mean % of CD34+ cells calculated in this experiment were A) 0.474%, B) 0.663%, C) 0.548%, D) 0.624% respectively. In our laboratory, we decided to use CD45-FITC/CD34-PE methods as a routine protocol.

데페록사민 전처치가 토끼 심근경색 크기의 감소에 미치는 효과

양관모,오동렬,박승현,박규남,이원재,김형국,황두영,최승필,채장성 대한응급의학회 1998 대한응급의학회지 Vol.9 No.4

Background: Reperfusion of ischemic myocardium has been postulated to result in a specific oxygen radical mediated tissue injury. Iron may liberate during ischemia and we hypothesized that administration of the iron chelator, deferoxamine during ischemia would result in improved recovery after postischemic reperfusion. Purpose: To test whether iron-catalyzed processes contribute to myocardial necrosis during ischemia and reperfusion, deferoxamine was administered to block iron catalyzed hydroxyl radical formation in rabbits. Methods: Eleven rabbits were divided into two groups : control group (n=5) and deferoxamine pretreatment group (n=6). The left circumflex coronay artery was ligated for 30 minutes and reperfused for 180 minutes. Area at risk (AR) was measured by non-stained area with methylene blue injection into left atrium after left circumflex coronary artery ligation. Infarct size was measured by weighing after triphenyltetrazolium chloride staining. Heart rate was measured using electrocardiographic recording and systemic blood pressure was monitored by pressure transducer connected to the catheter in the left ventricle. Results: 1. There was no significant difference of heart rate and blood pressure in deferoxamine pretreatment group compared with control group. 2. There was significant decrease of serum iron concentration after continuous infusion of deferoxamine compared with serum iron concentration before ligation of coronary artery(P<0.05). 3. There was no significant difference of area at risk between control and deferoxamine pretreatment group. 4. Area at necrosis to area at risk was significantly reduced in deferoxamine pretreatment group compared with control group(P<0.05). The results suggest that deferoxamine infusion prior to coronary artery occlusion has a significant benefit in reducing infarct size in this model.

유한요소법을 이용한 수직형 롤러 분쇄기용 테이블 라이너의 내구 해석에 관한 연구

최형모,이경영,조석수,이선봉 三陟大學校 産業科學技術硏究所 2002 産業科學技術硏究論文集 Vol.7 No.1

Vertical roller mill, which perform the grinding and parting blending of raw material, is the one of the important machine to produce ordinary portland cement. The table liner belonged to the vertical roller is mill the one of the main parts influencing its grinding efficiency. The life of table liner is estimatede to 4×107cycles in the design stage, but at the field, when its operating time reaches to 4×106 ~ 8×106 cycles, the fracture of table liner being to be found. The fracture of table liner commences from the outside edge of grinding path contacting with the grinding roller. Its maintenance normally take 30% of the total maintenance costs of the roller mill. Therefore, this study shows the clarification of the reasons occuring the fatal destruction of the table liner by fatigue fracture analysis utilizing fracture mechanics and by FEM using ANSYS 5.6.

주의력결핍 과잉행동장애 아동의 연령에 따른 특성비교

정영철,이종범,박형배,정성덕,성형모,사공정규 대한생물치료정신의학회 2001 생물치료정신의학 Vol.7 No.1

Objectives : This study is to verify the developmental changes of ADHD symptoms and functions with aging from 7 to 12 year-old. Method : The subjects of this study were 120 children(108 boys and 12 girls) who were diagnosed as ADHD by DSM - IV at department of neuropsychiatry of Yeungnam University Medical Center. Multidementional tests(K-ABC, ADDES-HV, CAP, CPT, KPl-C, WCST) were carried out to evaluate the change of ADHD symptoms and functions. Results : In K-ABC, children with ADHD showed statistically significant increased "Reading and Understanding" ability(p<.001) with age. In ADDES-HV, They showed decreased inattention (p<.05) and hyperactivity(p<.05) but, not showed significant change of impulsivity symptom with age. In CAP, They showed decreased hyperactivity(p<.001) and inattention (p<.05) and lower total score(p<.05) with age. their result were similar with ADDES-HV. In CPT, They showed decreased hit reaction time(p<.001) and hit reaction time standard errors(p<.01) and variability of standard errors(p<.05) with age. In KPI-C, They showed decreased anxiety(p<.01), depression(p<.001), somatization(p<.05), delinquency(p<.05) and hyperactivity(p<.01) with age. Social relationship(P<.05) was improved, as well as decreased psychoticism(p<.05) and autism (p<.001). In WCST, They showed increased completed categories(p<.001), total corrects(p<.001) and fewer total errors (p<.001) with age. Conclusion : Above findings indicate that symptoms of inattention and hyperactivity in school-aged ADHD children tend to decline with age, but age was less associated with decline in impulsivity symptom . In additions, Their executive functions were improved notably and they appeared stability of emotion, close social relationship and decreased delinquency.

흰쥐에서 반복적 스트레스가 GABA성 신경전달에 미치는 영향

김창수,이종범,성형모,시현석,김진성,박형배,정성덕,하정희 大韓神經精神醫學會 2000 신경정신의학 Vol.39 No.1

연구목적 : 일반적으로 생체는 각종 스트레스에 반응하여 적응(adaptation) 기전이 나타난다. 이러한 적응 기전과 관련하여 포유동물의 중요한 억제성 신경전달계인 GABA성 신경전달계의 스트레스성 자극에 대한 반응양상에 대한 연구가 진행되고 있다. 신경전달의 변화양상은 부하된 스트레스의 종류 및 기간에 따라 다양하게 나타나므로 더욱 상세한 연구를 필요로 한다. 방 법 : 본 연구에서는 하루 2시간의 부동화 스트레스를 반복적으로 2주간 부하한 흰쥐의 뇌조직에서 GABA성 신경전달의 변화 양상을 관찰하고자 하였다. 수용체 결합반응을 통하여 GABA 수용체의 각 component별 배위자들의 각 수용체에 대한 결합 반응의 변화 양상을 정상 대조군와 비교하여 보고, 유의한 변화가 있는 부분의 상세한 검정을 위하여 포화결합반응을 통하여 친화력(Kd) 및 최대결합력(Bmax)에서의 변화양상을 검색하였다. 뿐만 아니라 GABA성 신경전달에 관여하는 중요한 신경전달체인 내인성 GABA의 함량과 대사효소인 GABA transaminase의 활성도의 변화양상도 검색하였다. 결 과 : 연구결과 반복적인 부동화 스트레스는 GABA 수용체 효현제인 [³H]muscimol의 흰쥐 뇌조직 GABA 수용체에 대한 결합도에는 별다른 영향을 미치지 않았다. 대뇌피질조직의 GABA 대사효소인 GABA transaminase 활성도를 감소시켰으나, 피질조직외의 다른 조직의 GABA transaminase 활성도나 내인성 GABA의 농도에는 별다른 영향을 미치지 않았다. 반복적인 부동화 스트레스를 부하한 흰쥐의 대뇌피질, 해마 및 시상하부 조직에서는 [³H]flunitrazepam의 수용체 결합도가 감소하였으며, 포화결합 반응결과 수용체의 수가 감소하였음을 확인하였다. 결 론 : 이상의 결과를 요약하면, 흰쥐에게 부하한 반복적인 부동화 스트레스는 뇌조직의 benzodiazepine 수용체의 수를 감소시킴으로써 GABA성 신경전달을 감소시키며, 이러한 GABA성 신경전달계의 변환은 생체에서 스트레스로 인한 행동장애의 한 기전이 될 수 있을 것으로 생각되었다. Objectives : Changes of GABAergic neurotransmission in response to the application of different types of environmental stress have been the subject of research for over two decades. However, the nature of the changes induced by stress appear to show a dependent phenomena on the type and duration of stressor agent employed. Methods : For this reason, this study was performed to observe the effects of repeated stress on the radioligands binding to GABAA/benzodiazepine receptors of discrete brain regions. The author also examined the activity of GABA transaminase and the concentration of endogenous GABA. Male Sprague-Dawley rats, weighing 150-200g were forced to suffer an immobilization stress for 2 hours during 14 consecutive days. Results : Repeated immobilization stress decreased the binding of [3H]flunitrazepam on the benzodiazepine receptor in the cortex, hippocampus and hypothalamus. Saturation experiments followed by scatchard analyses of the results showed decreased density of benzodiazepine receptor and the affinity remained unchanged. Repeated immobilization stress did not affect the binding of [3H]muscimol on the GABAA receptor, the activity of GABA transaminase, and the concentration of endogenous GABA in the brain regions. Conclusions : From these results, it can be concluded that repeated immobilization stress modulated GABAergic neurotransmission via downregulation of the benzodiazepine receptor in the brain.

흰쥐에서 음경발기 평가의 척도로서 음경해면체내압측정술 확립

송윤섭,김용준,이광우,김준모,문기혁,박영호,민영기,유형균,김형건 순천향의학연구소 2001 Journal of Soonchunhyang Medical Science Vol.7 No.1

Purpose: Because studies about the control of penile erection at the entral nervous system was dependent on the animal experiments, establishment of measuring penile erection is important to evaluate the effects changes at the central nervous system on the penile erection. Intracavernous pressure measurement in rats has been introduced as a suitable index for the evaluation of penile erection but this method is invasive and technically difficult. So, we established the intracavernous pressure measurement in rats as the experimental index for penile erection. Materials and Methods: 42 male adult Sprague-Dawley rats (250-300gm) were divided to saline or papaverine treated group. Rats were placed on a heating table to maintain their body temparature and anesthetized with 50mg/kg of pentobarbital sodium by intraperitoneal injection. A cannula was inserted to the left carotid artery to measure systemic blood pressure. Saline (0.05, 0.1ml), papaverine(0.05, 0.1, 0.25, 0.5, 1.0, 2.0mg) were injected intracavernously via 26 guage needle filled with saline or papaverine which connected to pressure transducer and polygraph was inserted into the corpus cavernosum on one side to inject the drug and to measure intracavernous presure. Results: Properly executed insertion and intracavernous administration produced a instantaneous but transient rise in intracavernous pressure that substantially stabilized and maintained at 5.4±0.4mmHg. Intracavernous pressure and duration of penile blood flow following intracavernous injection of papaverine are increased comared to those of saline. Conclusions: Monitoring intracavernous pressure in rats represents a suitable index for the evaluation of penile erection in small laboratory animals.