해도분석을 통한 낙동강 하구 사주 면적의 시ㆍ공간 변화

유창일(CHANG-ILL YOO),윤한삼(HAN-SAM YOON),류청로(CHEONG-RO RYU),이인철(IN-CHEOL LEE) 한국해양공학회 2006 韓國海洋工學會誌 Vol.20 No.6

This study discusses characteristic of spatiotemporal changes of the sand barrier in the Nakdong estuarine for the last century, focusing on geomorphologic evolution and mobility of sand barriers in the view of coastal engineering. The Nakdong estuarine, the research subject, has a complexly changing natural environment by interaction between ground and marine elements such as ocean wave, tidal current, sediment, etc. Moreover, recently, unnatural geomorphologic changes (e.g., seaside reclamation, new harbor construction, etc.) has been radically increased in this area with increasing desire for coastal development. Because of this, its sand barrier has developed quite unstable condition. Therefore, to identify the development process of geomorphologic changes in this area, required is a close examination on historical characteristics of spatiotemporal changes of the sand barrier in relation to surrounding seaside reclamation and physical environmental changes. This study, based on the marine charts published in between 1927 and 1995 year, analyzes the length and area of the sand barrier for the last hundred years, and investigates the cause of the changes by looking into the change of water depth for the last two years and doing ocean-physical site observations. In conclusion, the sand barrier of the Nakdong estuarine expands toward the open sea by 7.4~26 m in annual average, maintaining a fixed distance of 1,241~1.279 m, and its area is expected to increase about 2.8 k㎡ annually. This is characterized by the wocean wave from the open sea and the discharge of Nakdong River.

쌀 품종별 제분특성 및 제빵적성에 관한 연구

유인수,허장성,윤인화 단국대학교 1998 論文集 Vol.33 No.-

This experiment was conducted to evaluate the characteristics of extruded rice flour, bread qualities of rice flour in blends with wheat flour and properties of the steam cooked rice bread for Korean rice varieties compared to the imported rice. Whiteness index and contents of crude fat and crude protein were higher in Korean rice varieties than in the imported rice, but the content of amylose was less than 20 percent in Korea varietes. Bread qualities score according to the 30% composition ratio of the extruded rice flour to wheat flour was inferior to the bread with only wheat flour in texture and color, but it was better in taste. Bread quality for rice varieties were good in order of Dongjinbyeo>Calrose>Dasanbyeo>Indian rice Panticle size of over 100 mesh was more in rice flour from the wet roller mill compare to the dry-pin mill in grinding methods. In amylogram characteristics, gelatinization temperature, peak viscosity, final viscosity were lower in rice flour from in wet roller mill than from the dry-pin mill. In varieties, Dongjinbyeo and Dasanbyeo were good for bread-making properties with lower value in amylogram charateristics. In score of the volume, hardness and taste for the steam cooked rice bread, the flour from the wet roller mill was higher than that from the drip-pin mill. In varieties, it was in order of Dongjinbyeo>Dasanbyeo>Calrose>Indian rice.

태풍내습시 수영만내에서의 파랑특성 분석을 위한 수치실험연구

김동환(Dong-Hwan Kim),유창일(Chang-Ill Yoo),이인철(In-Cheol Lee),김헌태(Heon-Tae Kim),류청로(Cheong-Ro Ryu) 한국해양환경·에너지학회 2012 한국해양환경공학회 학술대회논문집 Vol.2012 No.5

In order to research the wave characteristics in Suyeong bay on typhoons in 201this study were carried out observation of waves on typhoon "Ma-on" and "Muifa", calculation of wave characteristics using STWAVE and comparison with significant wave heights between observed and calculated data at three in-situ measurements (Geoje floating buoy, Gwangan light beacon, Observation point). The model input parameters are significant wave height, peak period and wave direction in Case 1 and changed edited wave direction instead of original it in Case 2. As the result of this study, the maximum significant wave height at Gwangan light beacon (St. 1) and Observation point (St. 2) in case of "Ma-on" was observed, respective^ 2.8m, 2.6m and calculated by STWAVE L76m, 2,8m Also, the maximum significant wave height in case of "Muifa" observed at St 1 and St 2 was 3.5m, 3.82m and calculated 25m, 3.97m, respectively. Our found significant differences between the observed and numerical in Gwangan light beacon on two typhoons but no significant differences between the observed and numerical in Observation point on two typhoons.

태풍내습시 수영만내에서의 파랑특성 분석을 위한 수치실험연구

김동환(Dong-Hwan Kim),유창일(Chang-Ill Yoo),이인철(In-Cheol Lee),김헌태(Heon-Tae Kim),류청로(Cheong-Ro Ryu) 대한조선학회 2012 대한조선학회 학술대회자료집 Vol.2012 No.5

In order to research the wave characteristics in Suyeong bay on typhoons in 2011, this study were carried out observation of waves on typhoon "Ma-on" and "Muifa", calculation of wave characteristics using STWAVE and comparison with significant wave heights between observed and calculated data at three in-situ measurements (Geoje floating buoy, Gwangan light beacon, Observation point). The model input parameters are significant wave height, peak period and wave direction in Case 1 and changed edited wave direction instead of original it in Case 2 As the result of this study, the maximum significant wave height at Gwangan light beacon (St.1) and Observation point (St. 2) in case of "Ma-on" was observed, respectively, 2.8m, 2.6m and calculated by STWAVE 1.76m, 2.8m. Also, the maximum significant wave height in case of "Muifa" observed at St. 1 and St. 2 was 3.5m, 3.82m and calculated 2.5m, 3.97m, respectively. Our found significant differences between the observed and numerical in Gwangan light beacon on two typhoons but no significant differences between the observed and numerical in Observation point on two typhoons.

래칭 릴레이의 온도에 따른 동작 특성 변화

류재만,진인영,허창수,Ryu, Jae-Man,Jin, In-Young,Huh, Chang-Su 한국전기전자재료학회 2017 전기전자재료학회논문지 Vol.30 No.8

Electrical relay in an essential part of smart grids, electrical vehicles, and LED lightning systems. Therefore, studying relay reliability is important. Relays using permanent magnet actuators (PMAs), which are energy efficient, are also in the spotlight. However, most of the permanent magnets used in PMAs have a characteristic wherein the magnetic flux decreases as the temperature increases. When the magnetic flux is reduced, the force acting on the actuator is reduced. Therefore, in this study, we measured the decrease in the relay operating speed with permanent magnet reduction due to temperature rise. In addition, changes in the bouncing phenomena due to magnetic flux reduction were analyzed. As a result, the operating speed of the relay has decreased and the bouncing phenomenon has not significantly changed.

기술교사의 역할에 대한 중등학교 기술교사의 인식

여인문,류창열 충남대학교 공업교육연구소 1995 論文集 Vol.18 No.1

This research was to find out the roles of technology teacher perceived by technology teachers. The specific objectives of the research were threefold; (1)to find out the expected roles for technology teacher based on the literature review, (2)to find out the roles for technology teacher perceived by technology teachers, (3)to find out real time input in each expected role for technology teacher. The method of this research was questionnaire survey conducted by the technology teachers. The technology teachers were selected by cluster sampling method. After data screening, 100 data were analyzed by frequency, percentage and paired T-test. The main findings of this research were as follows: (1)technology teachers teached 3.3 classes a day average. They spend 0.6 hours on evaluation after test, 0.8 hours in counseling students, 1.1 hours in managing official documents and doing office work, and 0.4 hours on activities related to industrial fields per a day average. (2)the optimal time spent per a day at school which technology teachers perceived were 2.8 hours in teaching, 1.7 hours in preparation of teaching, 0.5 hours in evaluation, 0.8 hours in counseling, 0.5 hours in managing documents, 0.4 hours in activities in relation to industrial fields. (3)technology teachers knew the importance of ability to teach student how to operate tools and machine, to demonstrate manufacturing technics, to develop students' crativity in technics, to manage workshop, to teach students safety in workshop. But technology teachers didn't spend their time and energy in these roles.

치은섬유아세포와 치은인대세포의 형태와 화학주성에 미치는 대조추출물의 효과에 관한 연구

양창호,류인철,최상묵,정종평,Yang, Chang-Ho,Ryu, In-Chul,Choi, Sang-Mook,Chung, Chong-Pyoung 대한치주과학회 1995 Journal of Periodontal & Implant Science Vol.25 No.2

The most important object of periodontal treatment is the perfect regeneration of destructed periodontal tissue. The healing of periodontal lesion is affected by several cells & factors, which result in formation of long juntional epithelium, root resorption, bony ankylosis or connective tissue attachment. And ideal healing is enhanced by epithilial exclusion or periodontal ligament cell activation. In this investigation, I studied the effect of Zizyphus Fructus extract which enhances biologic activity& collagen synthesis, on the chemotaxis & cell nature. The cells were obtained from interdental area & middle third area of the freshly extracted teeth for the orthodontic purpose. And they were fully incubated in${\alpha}-MEM$ solution containing $100{\mu]g/ml$ penicillin & $100{\mu]g/ml$ streptomycin followed by 6 generation incubation. The test cells were collected by trypsin-EDTA & centrifuge in the fully incubated cells, counted by Hernacyotmeter, incbated $5{\times}10^5/ml$ cells for 24 hours, re-incubated 24 hours in media containing natural extract and photographed. The cells were incubated for 4 hours in 48 well microchemotaxis chamber bisecting upper & lower chamber by 8ug/m pore polycarbonate membrane coating 5mg/ml gelatin solution. The migrated cells in microscope were counted, which meaned cell chemotaxis activity. The study had shown that the morphology of cell was spindle-shaped as the control group, and the subextract test groups were not significantly different. In gingival fibroblasts, the chemotaxis effect of PDGF was statistically significant compared to control group. The Zizyphus Fructus extract was more or less enhanced chemotaxis effect and in $1{\mu}g/ml$ concentration the chemotaxis effect was slightly elevated compared with $10{\mu}g/ml$ concentration. But, among the subextracts, it was not significantly defferent. In PDL cells, the chemotaxis effect of PDGF in statistically significant, and the zizyphus Fructus extract had shown the enhanced effect. The effect was slightly higher in $1{\mu}g/ml$ concentration than 10g/ml concentration,and no significance among the subextracts.

수리적 간극변화를 고려한 수리적 굴착손상영역의 정의에 관한 연구

박종성,류창하,이정인,류동우,Park, Jong-Sung,Ryu, Chang-Ha,Lee, Chung-In,Ryu, Dong-Woo 한국터널지하공간학회 2007 한국터널지하공간학회논문집 Vol.9 No.2

굴착손상영역(EDZ)은 굴착으로 인해 현지 암반이 역학적으로 손상을 입게 되어 응력상태, 변위상태, 암반의 안정성, 지하수의 흐름상태 등에 변화가 일어나는 영역을 의미한다. EDZ의 역학적 특성과 관련한 많은 연구들이 수행되었지만, EDZ에서의 지하수 유동 특성에 관한 연구는 아직 부족한 수준이다. 따라서 본 연구에서는 굴착으로 인해 굴착면 주변의 수리적 간극이 늘어나는 영역을 산정하여 '수리적 굴착손상영역'이라 정의하고 이를 위해 수리-역학적 상호작용(coupling)해석을 수행하였다. 이는 개별 불연속면 망의 생성을 통한 역학적, 수리적 변화의 모사가 가능한 개별요소법(discrete element method; DEM)을 이용하여 수행하였다. 이를 통해 EDZ에서 지하수의 흐름에 영향을 미치는 각종 조건들(불연속면의 간극, 불연속면 군의 방향, 불연속면 군의 길이, 불연속면의 각도 등)의 변화와, 응력분포, 지하수의 유동 등으로 인해 수리적 간극 값이 어떻게 변화하는지를 파악하였다. 이 결과를 토대로 수리적 간극이 커지는 영역, 수리적 EDZ를 공동 주변의 불연속면 방향에 수직 방향으로 존재하는 타원형의 형태로 모델링 하였다. The excavation damaged zone (EDZ) is an area around an excavation where in situ rock mass properties, stress condition, displacement, groundwater flow conditions have been altered due to the processes induced by the excavation. Various studies have been carried out on EDZ, but most studies have focused on the mechanical bahavior of EDZ by in situ experiment. Even though the EDZ could potentially form a high permeable pathway of groundwater flow, only a few studies were performed on the analysis of groundwater flow in EDZ. In this study, the 'hydraulic EDZ' was defined as the rock zone adjacent to the excavation where the hydraulic aperture has been changed due to the excavation by using H-M coupling analysis. Fundamental principles of distinct element method (DEM) were used in the analysis. In the same groundwater level, the behavior of hydraulic aperture near the cavern was analyzed for different stress ratios, initial apertures, fracture angles and fracture spacings by using a two-dimensional DEM program. We evaluate the excavation induced hydraulic aperture change. Using the results of the study, hydraulic EDZ was defined as an elliptical shape model perpendicular to the joint.

조석환경 변화에 의한 표층퇴적물의 시.공간적 분포 변화: 한국 서해안의 무안만

류상옥,장진호,이희준,조영조,최옥인,Ryu, Sang-Ock,Chang, Jin-Ho,Lee, Hee-Jun,Jo, Yeong-Jo,Choi, Ok-In 한국해양학회 2009 바다 Vol.14 No.1

하구언과 방조제 건설에 따라 고극조위 상승과 같은 조석환경 변화가 심한 무안만에서 표층퇴적물의 분포 변화와 변화 원인을 규명하기 위하여 퇴적물 시료를 채취하고 조류관측을 실시하였다. 무안만의 표층퇴적물은 1998년에 비해 역과 사의 조립질퇴적물의 함량이 증가하고 실트의 함량이 감소하여 퇴적물의 평균입도는 6.2${\phi}$에서 5.8${\phi}$로 조립해지는 경향을 보였다. 조립질퇴적물의 함량 증가와 실트의 함량 감소는 만조선 주변을 중심으로 광범위하게 나타났으며, 특히 동암리와 구로리, 압해도 조간대에서 두드러지게 나타났다. 만조선 주변의 조립화 현상은 일차적으로 하구언 및 방조제 건설에 따른 고극조위 상승에 기인하는 것으로 해석된다. 한편, 서측 만입구 주변에서 세립질퇴적물의 함량이 증가하는 현상은 인공구조물(교각) 건설에 따른 조류속의 감소와 위상차에 의한 조류의 방향 변화 등 수류의 변형에 기인하는 것으로 판단된다. Muan Bay has extensively undertaken artificial influences through a series of construction of dams and dykes nearby resulting in a substantial increase in highest high water level. To unravel sedimentary responses to the water level rise, we collected a number of surface sediment samples and hydrodynamic data from in-situ observations of tidal currents in Muan Bay in 1998 and 2007. Comparison of the data between 1998 and 2007 shows that the relative content of coarse fractions, sand and gravel, in the sediment samples has increased with a decreased mean size, on average, from 6.2 to 5.8${\phi}$ at the expense of silt contents. Such a coarsening trend, which is more evident around high water level, particularly on the tidal flats of Dongam-ri, Guro-ri and Aphae-do, is most likely attributable to rising water level. On the other hand, an increase of fine fractions locally in the western entrance of the bay can be explained with changes in characteristics of tidal currents imposed by construction of bridges therein, such as decreased velocities and varied direction and phase of the tidal currents.

靈岩灣 貝類의 重金屬 含量에 關한 硏究

장인애,류일광 광주보건대학 1976 論文集 Vol.3 No.-

A. A. S에 依하여 靈岩濟 具類中에 함유되어 있는 Cu, Pb, Mn, Cd, Zn, Hg등 6개 중금속을 分析하여 다음과 같은 결과를 얻었다. 1. Cu(구리)는 채취장소 Ⅰ에서 0.55∼0.57ppm, Ⅱ에서 0.82∼1.04ppm, Ⅲ에서 0.89∼1.13ppm, Ⅳ에서 0.29∼0.39ppm, Ⅴ에서 0.85ppm으로 나타났다. 2. Pd(鉛)는 채취장소 Ⅰ에서 0.04∼1.02ppm, Ⅱ에서 0.27∼0.98ppm, Ⅲ에 있어서는 0.20∼0.40ppm, Ⅳ에서 0.22∼0.29ppm, Ⅴ에서 0.29ppm으로 나타났다. 3. Mn(망간)은 채취장소 Ⅰ에서 2.05∼6.87ppm, Ⅱ에서 8.73∼16.97ppm, Ⅲ에서 5.12∼12.50ppm, Ⅳ에서 3.28∼11.68ppm, Ⅴ에서 10.66ppm으로 나타났다. 4. Cd(카드뮴)은 채취장소 Ⅰ에서는 檢出되지 않았고 Ⅱ에서 0.04∼005ppm, Ⅲ에서 0.11∼0.25ppm, Ⅳ에서는 1.25∼1.40ppm, Ⅴ에서 0.05ppm으로 나타났다. 5. Zu(아연)의 경우는 채취장소 Ⅰ에서 14.9∼16.0ppm, Ⅱ에서 20.1∼23.3ppm, Ⅲ에서 22.1∼23.3ppm, Ⅳ에서 14.1∼22.7ppm, Ⅴ에 있어서는 11.8ppm으로 나타났다. 6. Hg(수은)은 채취장소 Ⅰ에서 0.34ppm, Ⅱ에서는 檢出되지 않았고 Ⅲ에서 0.48ppm, Ⅳ에서 0.05ppm, Ⅴ에서 0.13ppm으로 나타났다. A survey was performed to determine the concentrations of six heavy metals (i. e., Cu, Pb, Mn, Cd, Zn and Hg) in several kinds of shellfishes which were collected in the Young-Ahm Bay during June to August 1976. The contents of six heavy metals were measured by Atomic Absorption Spectrophotometer(Perkm-Elmer Model 403). The results were summarized as follows: 1. Mean value of Cu, Pb, Mn, Cd, Zn and Hg contents was 0.73, 0.41, 8.65, 0.35, 18.59 and 0.20 ppm respectively. 2. In general, their concentrations were relatively low not to be significant in water pollution, but those of Cu and Hg appeared to be significant, for the maximal concentrations of Cd and Hg came to 1.40 and 0.48 ppm.