GMDP 신경망 알고리즘과 PID 제어기를 이용한 효율적인 PLANT 제어에 관한 연구

장진청,설재훈,장종승,추연규,임영도 동아대학교 공과대학 부설 한국자원개발연구소 1995 硏究報告 Vol.19 No.2

Adapative control theory or parameter tuning of PID controller is mainly limited in linear systems. But in this paper, using a nonlinear mapping capability of NNS, we derive a realtime tuning method of PID controller based on a Back-Propagation method of single GMDP NN. A variety of neural models, especially higher-order networks, are known to computationlly powerful for complex application. While they have advantages over traditional multilayered perceptrons, the uniformity in their network structures, learning algorithms and loop time creates practical problems. Thus this paper evaluates the capability between MLP and GMDP for performing velocity control. Backpropagation is applied to the GMDP as learning rule.

고강도 콘크리트 기둥부재의 횡보강효과 산정에 관한 연구

장일영,박훈규,송재호 金烏工科大學校 1998 論文集 Vol.19 No.-

High-strength concrete represents a rather recent development in concrete materials technology. In recent years, a considerable amount of research work has been carried out on the mechanical and structural properties of high-strength concrete. However, there has been little research on the behavior of hight-strength concrete columns laterally reinforced with square ties and subjected to compressive loading. With the addition of transverse reinforcement which lead to triaxial compressive state, ductility behavior of high-strength column member shall be increased. In this study, rational quality and quantity evaluations were made to investigate the ultimate strength and strain ductility by confinement effect of tie reinforced hight-strength concrete columns subject to uniaxial loads. Concrete failure theory at the triaxial compressive state and statistical results based on conventional experimental data were applied for this propose. Up to 185 columns, tested under monotonically increasing concentric loading, were evaluated in terms of strength and strain ductility. Analytical results show that confinement stress, maximum compressive strength, and increase of strain equations were developed with the consideration of concrete strength, yield strength, spacing, volumetric ratio, and configurations of tie reinforcement.

오스템퍼링한 구상흑연주철(ADI)의 드릴 가공시 경도 및 현미경조직변화에 관한 연구

조규재,장우양,심재기,홍성오,김선진 한국공작기계학회 1999 한국생산제조학회지 Vol.8 No.1

This paper was carried out to know the influence of advanced austempered ductile cast iron (ADI) on the tool life and mechanical properties of drilling machinability. For manufactured method of ADI, the spheroidal graphite cast iron were austenized at 900℃ for 1 hour and then austempered for 2 hour at 370℃ in the salt bath. And interrelationship has been investigated between tool life and mechanical characteristics of specimen material on drilling condition when the ordinary and step-feed drilling are carried out to drill holes of specimens. Tensile strength and hardness of ADI decrease and elongation of ADI increases with the increase austempered temperature. It is known that about 2 times of tool life in the case of step-feed decreases compared with ordinary feed due to the high hardness of ADI and hardness ascribed to the fact that retained austenite beame to martensite state due to cutting heat in drilling. Under the constant feed rate 0.1㎜/rev relation between hardness and length of end tip after drilling can be formularized to Hv=788.46L^-0.096 for the cutting speed 6.1m/min.

외상후 발작의 위험인자에 대한 조사

이재학,배학근,윤석만,도재원,이경석,윤일규,최순관,변박장 순천향의학연구소 2001 Journal of Soonchunhyang Medical Science Vol.7 No.1

Risk Factors for Posttraumatic Seizure The authors evaluate the risk factors for posttraumatic seizures. this prospective study was performed in a series of 470 head injured patient from January 1996 to Decomber 1998. The patients who were dead within 1 week of injury or children from 3 years old and under were excluded. There were 358 male and 112 female with a mean age of 35.2±22.8 years (range, 4-88 years). The results were as follows : 1). Of the 470 patients, pasttraumatic seizure occurred in 48 patients(10.2%): early seizure in 28(6%) and late seizure in 20 patients(4.2%). 2). The clinical risk factors for posttraumatic seizure were poor consciousness at admission, presence of brainstem herniation signs, poor GCS score, and posttraumatic amnesia more than 24 hours after trauma(p<0.001). 3). The radiological risk factors for posttraumatic seizure were subdural hematoma(p<0.001), intracerebral hematoma (p<0.02), mutiple intracranial CT lesions(p<0.001), or delayed lesions on follow-up CT scans(p<0.001). the incidence of seizure increased according to the severity of diffuse brain lesion(p<0.001), and the seizure rate in mass lesion was higher than that in diffuse lesion(p<0.001). 5). Hypoxia and coagulopathy had a statistically significant influence on posttraumatic seizure(p<0.05). Hypoxia had a infuence on occurrence of late seizure(p<0.05). 6). The incidence of posttraumatic seizure signiticantly increased in surgical group compared with coservative group(p<0.001) and significantly increased in patient who underwent decompressive craniectomy compared with those who underwent craniotomy(p<0.001) 7). Preventive administration of antiepileptic drugs decreased the incidence of early seizure, but did not affect on the reduction of late seizure. 8). Multivariate logistic regression analysis showed the subdural hematoma, GCS score, delayed lesion, and intracerebral hematoma in order of importance for seizure risk. in conclusion, the risk factors affecting on the occurrence of seizure were clinical status at admission, CT lesions, and severity of diffuse brain inJury. Considering that hypoxia affected on the late seizure, it is necessary to detect and treat it immediately after trauma. In addition, the patients who underwent decompressive craniectomy should be carefully followed to evaluate the risk of late seizure. Even though preventive administration of antiepileptic drugs had a tendency to decrease the incidence of early seizure, it is unclear whether administration of antiepileptic drugs can reduce the incidence of posttraumatic seizures. Prospective study will be needed in the selected patients.

특발성 자발성 신장 파열 1예

윤재철,김원,조규종,홍정석,이미우,장성은,오세현,임경수 대한응급의학회 2001 대한응급의학회지 Vol.12 No.4

Primary aldosteronism is a syndrome characterized by hypertension, hypokalemia, suppressed plasma renin activity, and elevated serum aldosterone levels. Conn first described it 1955 in association with adrenal cortical adenoma(Conn's syndrome). Today, it can be divided into at least six distinctive sub-groups. The diagnosis of primary aldosteronism is usually suspected when the patient presents with poorly controlled hypertension with hypokalemia. The main issues in the evaluation of primary aldosteronism are to differentiate an adenoma from hyperplasia and to localize the adenoma. Basic hormonal studies and computed tomographic(CT) scanning can be used effectively for that differentiation. An adenoma is one of a few potentially curable forms of hypertension, and it is best treated by removing the adrenal tumor. We experienced a case of a typical adrenal adenoma. The patient was a 37-year-old male who had experienced in both his legs over a period of several days a weakness due to hypokalemia. He was diagnosed using basic hormonal studies and adrenal CT scanning. After, he received laparoscopic adrenalectomy and was discharged with improved condition.

자발성 뇌지주막하 출혈 환자에서 최초 뇌실 크기의 임상적 의의

신일영,윤일규,윤석만,도재원,이경석,배학근,최순관,변박장 순천향의학연구소 2001 Journal of Soonchunhyang Medical Science Vol.7 No.1

The purpose of this study is to invesetigate the clinical significance of initial enlargement of ventricle in the patients who had aneurysmal SAH. Of the total 821 patients with aneursmal SAH who were registerd in SAH data bank system between 1989-1999, 307 patients who had been already measured in the size of ventricle at the time of admission, were studied retrospectively. The size of ventricle was calculated by bifrontal index. Normal size of ventricle was defined as 30% or less, mild enlargement was defined as 31 to 39%, and moderate enlargement of vertricle was defined as more than 39% in bifrontal index. The sizes of ventricle using bifrontal index were analysed according to the age, sex, blood pressure, consciousness at admission, medical history of hypertension, location of ruptured aneurysm, Fisher's grade on CT(computerized tomography) scan at the time of admission, cerebral vasospasm, intraventricular hemorrhage (IVH), performance of external ventricular drainage (EVD), and prognosis at discherge. Chi-square test and ANONA were used in the statistical evaluation. The results were as follows : 1) Of the 307 patients, 235(76.5%) had a mild to moderate enlargement of ventricle at the time of admission (more than 30% in bifrontal index). 2) The size of ventricle was enlarged according to the increase of age (p<0.05). 3) In the patients who had ruptured aneurysm on anterior cerebral artery, the size of ventricle significantly increased and showed a higher incidence in mild enlargement compared with moderate enlargement of ventricle (p<0.05). 4) The size of ventricle increased in th patients who had IVH and the EVD was more frequently performed in th patients who had the enlarged ventricle associated with IVH (p<0.05). 5) In the patients who had high Fisher's grade, the size of ventricle had a tendency to increase, but there was no statistical significance. 6) In the patients who had poor prognosis, the size of ventricle had a tendency to increase, but there was no statistical significance. Conclusively, the initial size of ventricle was enlarged in th aged patients, ruptured aneurysm on anterior communicating artery, high FIsher's grade, patients associated with IVH. Considering those factors, prediction for the enlargement of ventricle size may help to treat the patients suffering aneurysmal SAH.

유카 Ag-aide가 페어리링 병이 발생한 잔디토양의 투수계수 및 한지형 잔디 생육에 미치는 영향

김두환,이재필,함선규,장진혁,김성태 건국대학교 농업자원개발연구소 2000 農資源開發論集 Vol.22 No.-

Yucca Ag-aide extracted from Yucca, Agavaceae, is one of the several surface active agents being marked as a soil conditioner for turfgrass. According to the previous research, Yucca can provide an energy source for soil microbes, improve physical properties, and nutrient efficiency in soil, and enhance water infiltration capacity of soil. Yucca was applied to the tee area with cool-season grass showing fairy ring symptom at the Asiana Country Club from June to July, 1999. Yucca was also applied to "Pencross" creeping bentgrass that was stressed by 15 and 30 times of glass stick once every two months(three time total) in 5cm diameter of PVC pipe in greenhouse and to experiment field, established with 35% Tall fescue+50% Kentucky bluegrass+15%Perennial ryegrass at the Kon-kuk University on June 8, 1999. Infiltration at the tee area showing fairy ring symptom was improved by treatment of 250 and 500 fold of Yucca Ag-aide. Yucca Ag-aide treatment also improved root length and dry weight of creeping bentgrass with the stress by glass stick. Coverage and turf quality of cool-season turfgrass in field trial were increased by Yucca Ag-aide. Clipping dry weight was also increased by the treatment.

수도권 매립지 주변의 지표수 오염에 관한 연구

이인현,장원,백영,도갑수,최재규 한국환경과학회 1997 한국환경과학회지 Vol.6 No.6

In order to analyze the water quality variation of surface water around the Sudokwon landfill site, seasonal variations of water temperature, pH, DO, BOD, COD, SS, NH_3-N. NO_2-N, and NO_3-N were examined at 10 sites from January to December, 1996. It was found that the estimates of COD, DO, SS, and NH_3-N were increased compared with the results of environmental impact assessment carried out in 1988. Higher estimates of COD, DO, and SS were due to industrial and agricultural wastewater, and the increase of NH_3-N at Jangdo reservoir site was due to the leachate from the landfill. In particular, the estimate of SS was found to be increased by the soil wash from the landfill during the heavy rainy days.

Pb의 노출에 따른 넙치, Paralichthys olivaceus, 치어의 생존, 성장 및 산소소비율의 변화

김성길,김재원,장석우,김상규,강주찬 한국어병학회 2002 한국어병학회지 Vol.15 No.3

Experiments were carried out to investigate the effects of lead exposure on survival, growth and oxygen consumption of juvenile oliver flounder, Paralichthys olivaceus. Survival rate of the oliver flounder was significantly affected above 150㎍/L. Growth of the olive flounder exposed to ≥ 150 ㎍/L of lead concentration was significantly lower than that of fish reared in normal condition. Metabolic rate of fish exposed to lead ≥ 80 ㎍/L concentration was significantly reduced with increasing lead concentration than that in normal condition. This study revealed that high lead concentration (≥ 80 ㎍/L) reduced growth and metabolic rates of juvenile olive flounder suggesting potential influence of lead on the natural mortality of olive flounder in the coastal areas.

KAL기 추락에 의한 대량재해의 개인식별

강신몽,이원태,고영창,최상규,김윤희,이홍석,서재관,윤중진,이혜경,최득린,김종열,윤창육,변명식,이장홍 大韓法醫學會 1991 대한법의학회지 Vol.15 No.2

Individual identification is an important part in medicolegal field especially in mass disaster. At July, 27, 1989, KAL KE-803 was crashed on landing at Tripoli International Airport, Liba. The plane was caught in fire and sixty eight Koreans were sacrified. The majority of victims were severely charred and injured. The authors examed all dead bodies and successfully identified all the cases through visual, anthropological, odontological, radiological and pathological methods including fingerprint and blood typing.