부여 취수장의 $NH_3-N$자료에 대한 평균 및 분산추정

김형수,정건희,김응석,김중훈,Kim, Hyeong-Su,Jeong, Geon-Hui,Kim, Eung-Seok,Kim, Jung-Hun 한국수자원학회 2001 한국수자원학회논문집 Vol.34 No.4

실험 또는 계측에 의해 관측된 관측치들은 종종 어떤 기준치 이하의 작은 값들이 기록되는데, 이들 기준치 이하의 값들이 크기는 미소할지라도 평균이나 분산 추정시 왜곡된 결과를 줄 수 있다. 그러나 우리 나라에서는 관측오차로 간주하여 N.D.(Not Detected)로 처리하는 것을 관례로 하고 있어 미소치들이 기록되지 않고 있다. EK라서 본 연구에서는 부여 취수장의 암모니아성 질소(NH$_3$-N)자료가 크기에 따라 분표형이 다름을 조사하고 그 분포를 구별할 수 있는 기준치와 기준치 이하의 자료들에 대한 평균과 분산 추정시 가장 적절한 기법을 찾고자 하였다. 즉, 기준치 이하의 값들과 이상의 값들을 구분하여 평균과 분산을 위한 적절한 기법을 선정하여 추정하였다. 분석 결과 부여취사장의 자료는 편기 수정된 최우도(Bias Corrected ML)법이 가장 적합한 것으로 결정되었으며, 시행착오법에 의하여 기준치를 설정하였다. Sometimes the observed data is too small to discriminate it from noise of the instrument. Say, the data can be recorded as below DL(Detection Level) value. Even though the data below Detection Level(BDL) is small vague, it can be resulted in wrong estimates for mean and variance. However, in practice, the BDL data is generally eliminated as N.D. (Not Detected) and do not record it in Korea. This study investigates the distributions according to the data values of ammonia concentration (NH$_3$-N) in Puyeo intake. Also we try to find out DL value and an appropriate method for the estimations of mean and variance of BDL values that can be discriminate the distributions. The DL is estimated by trial and error method. The appropriate method for the estimations of mean and variance of above the detection level(ADL)and BDL dada sets is selected, and the mean and variance are estimated. As a result, it is found that the Bias Corrected Maximum Likelihood Estimator is the most accurate method for NH$_3$-N in Puyeo intake.

강우와 홍수의 인자료에 대한 평균 및 분산추정

김형수,정건희,김중훈,김태균,Kim, Hyeong-Su,Jeong, Geon-Hui,Kim, Jung-Hun,Kim, Tae-Gyun 한국수자원학회 2000 한국수자원학회논문집 Vol.33 No.1

우포늪의 생태치수기능 개선을 위한 천변저류지 검토

김형수,경민수,김상단,김재근,김덕길,Kim, Hyeong-Soo,Gyeong, Min-Soo,Kim, Sang-Dan,Kim, Jae-Geun,Kim, Deok-Gil 한국수자원학회 2007 물과 미래(한국수자원학회지) Vol.40 No.4

분말사출성형 시 분말 혼합체의 유동성 시뮬레이션을 통한 투광성 알루미나 소결체의 특성 연구

김형수,변종민,김세훈,김영도,Kim, Hyung Soo,Byun, Jong Min,Kim, Se Hoon,Kim, Young Do 한국분말야금학회 2014 한국분말재료학회지 (KPMI) Vol.21 No.3

Translucent alumina is a potential candidate for high temperature application as a replacement of the glass or polymer. Recently, due to the increasing demand of high power light emitting diode (LED), there is a growing interest in the translucent alumina. Since the translucent property is very sensitive to the internal defect, such as voids inside or abnormal grain growth of sintered alumina, it is important to fabricate the defect-free product through the fabrication process. Powder injection molding (PIM) has been commonly applied for the fabrication of complex shaped products. Among the many parameters of PIM, the flowability of powder/binder mixture becomes more significant especially for the shape of the cavity with thin thickness. Two different positions of the gate were applied during PIM using the disc type of die. The binder was removed by solvent extraction method and the brown compact was sintered at $1750^{\circ}C$ for 3 hours in a vacuum. The flowability was also simulated using moldflow (MPI 6.0) with two different types of gate. The effect of the flowability of powder/binder mixture on the microstructure of the sintered specimen was studied with the analysis of the simulation result.

일부 농촌주민에서 Alcohol Use Disorders Identification Test를 이용한 위험 및 유해 음주율 조사

김형수,이건세,김청식,김기옥,장성훈,Kim, Hyeong-Su,Lee, Kun-Sei,Kim, Cheong-Sik,Kim, Ki-Ock,Chang, Soung-Hoon 대한예방의학회 2001 예방의학회지 Vol.34 No.3

Objectives : To investigate the prevalence of hazardous and harmful alcohol use, which are a subthreshold of alcohol related disorders, Methods : Direct-interview questionnaires to 1,183 rural persons (489 male, 694 female) were conducted in Chungju-city from July 2 to 20, 1998. As a screening instrument, the alcohol use disorders identification test (AUDIT) was used. Results : The prevalence of alcohol use was 41.7%. In males, it was 66.3% and in females, it was 24.4%. The mean of the AUDIT score of males and females was 13.2 and 5.6, respectively. As WHO guideline, the prevalence of hazardous alcohol use in males and females was 80.3% and 20.7%, respectively. This suggests that the prevalence of 'hazardous drinking' and 'harmful drinking' was 45.4% and 29.3% for males and 1.2% and 2.4% for females, respectively. Conclusions : This study presented the prevalence of hazardous and harmful drinking of a rural population in Korea and reviewed those health problems. Further evaluation to detect and treat lower alcoholic drinkers is recommended.

천변저류지를 이용한 우포늪 주변지역 습지의 확대방안

김형수,박성제,박창근,김재근,김상단,박재현,경민수,김덕길,Kim, Hyeong-Su,Park Seong-Je,Park Chang-Geun,Kim Jae-Geun,Kim Sang-Dan,Park Jae-Hyeon,Gyeong Min-Su,Kim Deok-Gil 한국하천협회 2007 하천과 문화 Vol.3 No.2

Laser Doppler Flowmetry를 이용한 치은혈류량에 관한 연구

김형수,이장희,송형근,김병옥,한경윤,Kim, Hyung Soo,Lee, Zang-Hee,Song, Hyung-Geun,Kim, Byung-Ock,Han, Kyung-Yoon 대한치주과학회 1998 Journal of Periodontal & Implant Science Vol.28 No.2

The periodontal health has been evaluated clinically by various epidemiological indices, and in researches by measurement of gingival crevicular fluid. Laser Doppler flowmetry is a reliable and objective method that allows immediate measurement of erythrocyte flux in approximately one cubic mm of the capillary bed without disturbing the tissues. The purpose of the present study was to determine whether human gingival blood flow was different according to measuring area, measuring time, and sex or not. Forty volunteers with good general and periodontal health, aged early twenties and unmarried, were selected. Laser Doppler flowmetry($floLAB^{(R)}$, Moor Instruments Ltd., England) was applied to measure the gingival blood flow of marginal gingiva, interdental papilla, attached gingiva and alveolar mucosa. The blood flow of interdental papilla was measured at 9-10 AM, 1-2 PM, and 5-6 PM. The difference of blood flow according to measuring area and measuring time was statistically analyzed by one way AOVA and Dunkan test, and the difference of blood flow between men and women was statistically analyzed by t-test. (1) Mean blood flow was significantly higher in alveolar mucosa than in the gingiva(p<0.05), and there was no significant difference in blood flow between marginal gingiva and interdental papilla(p>0.1). (2) Mean blood flow was significantly higher at 5-6 PM than at 9-10 AM and 1-2 PM(p<0.05). But there was no significant difference in gingival blood flow between 9-10 AM and 1-2 PM(p>0.1). (3) There was no significant difference in gingival blood flow between men and women(p>0.1). The above results suggest that the measurment of gingival blood flow using laser Doppler flowmetry may be clinically applicable to early determination of gingival inflammation and evaluation of healing status, but further studies are necessary to standardize and simplify the measuring procedure.

Trevor 병; 편측성 골단 이형성증 - 증례 보고 -

김형수,장준희,Kim, Hyoung-Soo,Chang, Jun-Hee 대한정형외과스포츠의학회 2009 대한정형외과스포츠의학회지 Vol.8 No.1

Trevor 병이라고도 불리는 편측성 골단 이형성증(dysplasia epiphysealis hemimelica)은 2세에서 14세 연령에서 한측 사지의 내측 또는 외측의 편측 골단부의 연골 이상 발육을 특징으로 하는 소아기의 드문 희귀 질환이다. 국내에서는 술 후 재발한 1례를 포함하여 6례가 보고 되었다. 본 교실에서 경험한 7세 남아는 좌측 슬관절의 통증을 호소하나 슬관절의 변형은 없었다. 단순 방사선 소견상 우슬부 대퇴골 원위부 내과의 골단 내측에 여러 개의 편심성 화골점이 관찰되었고, 자기 공명 영상 소견상 골단부 내측에 불규칙한 화골점 및 비정상적인 연골 비대가 확인되었다. 본 교실에서는 대퇴 내과 골단에 발생한 임상적으로 매우 드문 희귀 질환을 경험하여 자기 공명 영상 소견을 포함하여 문헌 고찰과 함께 보고하는 바이다. Trevor's disease, also known as dysplasia epiphysealis hemimelica, is rare abnormality characterized by aberrant cartilaginous overgrowth forming one half of epiphysis. Typically the patient is 2 to 14 years of age. Until now only six cases, including a case recurred after surgery, have been reported in Korea. A seven year-old boy complained pain of the left knee. However, any deformity of the knee was not seen. The plain radiographic findings showed multiple ossifications asymmetrically on the medial epiphysis of distal femur. The magnetic resonance imaging (MRI) clearly demonstrated the epiphyseal mass which contained low signal spots corresponding to calcified foci and abnormal cartilaginous overgrowth. We report one additional case with a brief review of literature with the MRI findings.

관절경적 전방 십자 인대 재건술 - 골-슬개건-골과 4중 슬괵건 자가이식의 전향적 비교 연구 -

김형수,박승림,강준순,이우형,김영훈,박주식,Kim, Hyoung-Soo,Park, Seung-Rim,Kang, Joon-Soon,Lee, Woo-Hyoeng,Kim, Young-Hoon,Park, Ju-Sik 대한관절경학회 1998 대한관절경학회지 Vol.2 No.1

Purpose : The purpose of this study was to compare the postoperative success and stability of arthroscopically assisted anterior cruciate ligament(ACL) reconstructions using the central one third bone patellar tendon bone(BPB) autograft versus a quadrupled semitendinosus/gracilis(ST) autograft in patients with "isolated" ACL tears. Materials & Methods : A strict criteria to identify isolated ACL tears was used which included : no previous surgery, no other ligamentous injury, no history of patellofemoral symptoms, no patellofemoral malalignment, no meniscal pathology, no chondromalacia or chondral injury and no limitation of motion of the injured knee. 30 patients (15 BPB, 15 ST) with a mean age of 27.4 years were available for a mean follow up of 18 months (between 12 months and 26 months). Preoperatively, there was no significant difference between the two groups with respect to age, sex and degree of laxity. Results : Postoperatively, we couldn't find significant differences between the two groups with respect to subjective Lysholm score, objective laxity including Lachman test, pivot shift test and KT-2000 measurements. Mean side to side difference of KT-2000 scores at 20lbs were 1.5mm for the BPB group and 1.4mm for the ST group. Positive Lachman test was found in 26.7% and 33.3% and positive pivot shift was found in 20% and 33.3% of the patients in the BPB and ST groups, respectively. Anterior knee pain (33.3%) was more common in the BPB group. There were 80% of the patients in both groups above nearly normal grade according to the IKDC grade. Conclusions : In patients with "isolated" ACL tears, the overall results, ligamentous stability for the patellar tendon and the quadrupled semitendinosus/gracilis were comparable. We consider that the quadrupled autogenous hamstring tendon is a good alternative substitute in ACL reconstruction together with the bone patellar tendon bone.

후방 십자 인대의 해부학과 생역학

김형수,Kim, Hyoung-Soo 대한관절경학회 1998 대한관절경학회지 Vol.2 No.1

As with anterior cruciate ligament reconstruction, posterior cruciate ligament(PCL) reconstruction requires a good understanding of the anatomy and biomechanical properties of the PCL to place the graft correctly as well as to choose the appropriate structure and material for the graft. The anatomy and function of the PCL can be somewhat confusing and continuing to evolve so far. Recent studies have focused on the insertion site anatomy and the identification of the functional components of the ligament. The issue of the ligament isometry and the role of PCL in knee kinematics are still totally resolved. This article can be provided an update on current concepts of the anatomy and biomechanics of the PCL through literature reviews. A clear understanding of these knowledges enables the clinicians to diagnose injuries to the PCL accurately and to reconstruct these structures successfully.