조위변동(潮位變動)을 받는 호안제(護岸堤)의 사면안정해석(斜面安定解析)

김상규,Kim, Sang Kyu 대한토목학회 1988 대한토목학회논문집 Vol.8 No.3

하루에 두번씩 10m의 진폭을 가지고 조위(潮位)가 계속해서 변화(變化)한다고 가정하여 한 대표적인 호안제(護岸提) 단면에 대해 사면안정해석(斜面安定解析)을 행한다. 조위(潮位)가 변화(變化)하는 동안 호안제내(護岸提內) 간극수압(間隙水壓)의 변화(變化)는 전산 프로그램 "FLUMP"에 의해 수행되며 이 프로그램은 포화(飽和)흐름은 물론 비포화(非飽和)흐름과 비정상(非正常) 흐름까지 고려될 수 있도록 짜여져 있다. 이 프로그램으로 얻어진 결과는 조위변동시(潮位變動時)의 자유수면(自由水面) 변화(變化)와 정(正) 및 부간극수압(負間隙水壓)의 크기와 분포를 명확하게 결정할 수 있음을 보여주고 있다. 조위(潮位)가 최저(最低)까지 내려갔을 때 제체내(堤體內) 어느 부분에서는 압력수두(壓力水頭)가 자유수면(自由水面)의 높이보다 더 높게 나타난다. 즉 이것은 조위변동(潮位變動)을 받는 호안제(護岸堤)의 일부에 과잉간극수압(過剩間隙水壓)이 발생함을 의미한다. 또한 부간극수압(負間隙水壓)이 나타나는 불포화영역(不飽和領域)이 조위강하시(潮位降下時)에 일시적(一時的)으로 발생한다. 이 불포화영역(不飽和領域)의 흙의 전단강도(剪斷强度)는 간극수압(間隙水壓)이 정(正)의 상태로부터 부(負)로 바뀔때 증가(增加)되며 이 값은 Fredlund 등이 제안한 방법에 따라 결정될 수 있다. 호안제(護岸堤) 사면(斜面)의 안정해석(安定解析)에 있어서는 조위변동시(潮位變動時) 발생되는 과잉간극수압(過剩間隙水壓)과 불포화영역(不飽和領域)의 부간극수압(負間隙水壓)이 반드시 고려되어야 한다는 것을 이 논문에서 강조하고 있다. 이것들이 고려되었을 때 임계활동원은 조위(潮位)가 최저(最低)로 되었을 때 얻어지는 자유수면(自由水面)보다 아래에 존재하는 것 같다. Assuming that tidal level is constantly changed with an amplitude of 10 meters and a cycle of 12 hours, the slope stability for a typical dyke is analysed. The variation of pore water pressure within the dyke during the tidal change is obtained using a computer program, FLUMP, which is incorporated with saturated-unsaturated and transient flow. The results show that the variation of free water surface and distribution of pore water pressure within the dyke during the tidal fluctuations can be clearly predicted with the computer program. When a tide is lowered to the minimum level, the predicted pressure head is higher than the level of the free water surface in some parts of the dyke; that is, excess pore water pressure is generated in a zone affected by the tidal change. Also an unsaturated zone which shows negative pore water pressure is temporally created when a tide is lowered. The shear strength of the zone can be predicted based on the proposal suggested by Fredlund et al. It is emphasized that the excess pore water pressure generated during tidal fluctuations and strength parameters for the unsaturated zone should be considered in analyzing the slope stability of dykes. When those are considered, the critical slip surface seems to be located below the free water surface obtained when a tide is at the lowest.

소양강(昭陽江)댐의 거동(擧動)에 대한 유한요소해석(有限要素解析)과 실측치(實測値)와의 비교(比較)

김상규,임희대,Kim, Sang Kyu,Lim, Heui Dae 대한토목학회 1987 대한토목학회논문집 Vol.7 No.1

1973년(年)에 완공(完工)된 소양강댐은 매설계기가 잘 설치되어 그 댐의 응력(應力)과 변형(變形)의 측정결과는 이미 발표된 바 있다. 그러나 이론적(理論的)인 해석은 지금까지 이루어지지 않았다. 본(本)연구(硏究)는 시공시(施工時) 재료의 자중을 받고 또 담수시 물 하중을 받게 되는 댐 본체의 응력(應力)과 변형(變形) 거동을 수치적(數値的)으로 해석하려는데 그 목적(目的)이 있다. 해석(解析)에 사용(使用)된 구성법칙(構成法則)은 Duncan 등(等)이 개발한 hyperbolic 모델이며, 시공단계(施工段階)를 모방한 비선형증가(非線型增加) 유한요소해석(有限要素解析)이 본(本) 연구(硏究)에 적용되었다. hyperbolic 파라미터들은 문헌에서 추정하여 사용(使用)하였다. 이론적(理論的) 해석(解析)으로부터 얻어진 결과는 댐의 임의의 단면에서의 변형특성과 응력벡타를 명확(明確)하게 나타내었다. 해석결과는 최대단면(最大斷面)에서의 변형측정치(變形測定値)와 잘 일치(一致)하였으나 수평변형(水平變形)과 심벽(心壁)에 생긴 응력에 있어서는 약간의 차이를 보였다. 수치해석과 측정치와의 비교(比較)로부터 얻은 본댐의 거동의 특징(特徵)은 심벽에서 비교적(比較的) 큰 시공침하(施工沈下)가 생겼고, 심벽의 토피하중(土被荷重)은 아아칭 효과에 의해 상당히 감소되었고, 또 양안부근(兩岸附近)에서는 수평변위(水平變位)가 커서 인장구역(引張區域)이 생길 수 있다는 것이다. The Soyanggang Dam completed in 1973 was well instrumented during construction period. The measured results for stresses and movements of the embankment have already been published elsewhere, but theoretical analyses have not been made until now. This study intends to analyze the stress and deformation behavior of the embankment numerically which have been subjected to the load of materials during construction and water load during impounding. The constitutive law used for the analyses is hyperbolic model developed by Duncan et al., and a nonlinear incremental finite element analysis simulating its contruction steps is. used in this study. Hyperbolic parameters for each Zone are estimated from literature. The results obtained from the theoretical analyses clearly show deformation characteristics and stress vectors in arbitrary section of the dam. The analytical results ate well agreed with the measured deformations at the maximum cross section, however, there are some discrepancy in horizontal movements and in stresses generated in the core zone. From the numerical analyses and its comparison with the measured values, it is charaterized that relatively large construction settlements occurred in core zone, overburden pressure in the core zone was considerably reduced by arching effect, and tension zones might occur near both abutments because of the large horizontal displacement.

PLL을 이용한 고속 마이크로프로세서용 32MHz~1GHz 광대역 클럭발생회로

김상규,이재형,이수형,정강민,Kim, Sang-Kyu,Lee, Jae-Hyung,Lee, Soo-Hyung,Chung, Kang-Min 한국정보처리학회 2000 정보처리논문지 Vol.7 No.1

This paper presents a low power PLL based clock geneator circuit for microprocessors. It generates 32MHz${\sim}$1GHz clocks and can be integrated inside microprocessor chips. A high speed D Flip-Flop is designed using dynamic differential latch and a new Phase Frequency Detector(PFD) based on this FF is presented. The PFD enjoys low error characteristics in phase sensitivity and the PLL using this PFD has a low phase error. To improve the linearity of voltage controlled oscillator(VCO) in PLL, the voltage to current converter and current controlled oscillator combination is suggested. The resulting PLL provides wide lock range and extends frequency of generated clocks over 1 GHz. The clock generator is designed by using $0.65\;{\mu}m$ CMOS full custom technology and operates with $11\;{\mu}s$ lock-in time. The power consumption is less than 20mW. 본 연구에서 PLL을 이용한 고속 마이크로프로세서용 클럭발생회로를 설계하였다. 이 회로는 32MHz${\sim}$1GHz 클럭을 발생시키며 마이크로프로세서내에 내장될 수 있다. 동적 차동래치를 사용하여 고속 D Flip-Flop을 설게하였고 이에 의거한 새로운 형태의 위상주파수 검출기를 제시하였다. 이 검출기는 위상민감도오차가 매우 적으며 이를 사용한 PLL은 위상오차가 적은 우수한 위상특성을 지닌다. 또한 전압제어발진기 VCO의 선형적 제어를 위하여 전압-전류 변환기가 구동하는 전류제어 발진기로 구성된 새로운 구조의 VCO를 제시하였다. 이러한 PLL에서 제어전압 범위를 1V${\sim}$5V로 넓히고 발생클럭의 주파수를 32 MHz${\sim}$1 GHz로 증가시킬 수 있었다. 클럭발생회로는 $0.65\;{\mu}m$ CMOS 기술을 이용하여 설계하였다. 이 회로는 $1.1\;{\mu}s$의 lock-in 시간과 20mW 이하의 전력소비를 갖는다.

유비쿼터스 헬스케어를 위한 전기화학 바이오센서

김상규,정봉현,Kim, Sang-Kyu,Chung, Bong-Hyun 대한의용생체공학회 2008 의공학회지 Vol.29 No.5

To date, many researchers have developed a variety of biosensors to detect the biomolecular interactions. Recently, electrochemical biosensors have been attracting great interest as one of key technologies in a ubiquitous healthcare (U-healthcare) system since they are highly sensitive and feasible to miniaturize. Here we overview the current electrochemical biosensors based on strip-type, nanowire/nanotube, field effect transistor (FET), and nanogap electrode.

추적관찰을 통한 일개 농촌 노인의 인지기능변화와 관련요인

김상규,황태윤,사공준,이경수,강복수,Kim, Sang-Kyu,Hwang, Tae-Yoon,SaKong, Joon,Lee, Kyeong-Soo,Kang, Pock-Soo 대한예방의학회 2007 예방의학회지 Vol.40 No.2

Objectives : This prospective population-based cohort study was conducted to evaluate the risk factors of cognitive impairment and the degree of cognitive function change through a 5-year follow-up. Methods : The baseline and follow-up surveys were conducted in 1998 and 2003, respectively, Among 176 subjects who had normal cognitive function in the baseline study, 136 were followed up for 5 years. The cognitive function was investigated using the Korean version of the Mini-Mental State Examination (MMSE-K). The collected data were analyzed using SPSS and Stata. Results : Of the 136 subjects analyzed, 25 (18.4%) were cognitively impaired. Old age and low social support in the baseline survey were risk factors for cognitive impairment after 5 years. In the generalized estimating equation for 128 subjects except severe cognitive impairment about the contributing factors of cognitive function change, the interval of 5 years decreased MMSE-K score by 1.02 and the cognitive function was adversely affected with increasing age, decreasing education and decreasing social support. Conclusions : Although the study population was small, it was considered that the study results can be used to develop a community-based prevention system for cognitive impairment.

일개 농촌지역 노인의 아포지단백 E 다형성과 인지기능 변화

김상규,황태윤,이경수,강복수,조희순,배영경,Kim, Sang-Kyu,Hwang, Tae-Yoon,Lee, Kyeong-Soo,Kang, Pock-Soo,Cho, Hee-Soon,Bae, Young-Kyung 대한예방의학회 2009 예방의학회지 Vol.42 No.4

Objectives : The aim of this study is to examine the cognitive function change related to aging, the incidence of cognitive impairment, and the association between apolipoprotein E polymorphism and cognitive impairment through a follow-up of the elderly with normal cognitive ability at baseline. Methods : Two hundred and fifteen subjects aged 65 and over were surveyed in February, 1998 (baseline survey), and their cognitive function was assessed again in 2003 1st follow-up) and the once again in 2006 (2nd follow-up). Ninety one subjects completed all surveys up through the 2nd follow-up and their cognitive function scores using MMSE-K (Korean Version of the Mini-Mental State Examination) and the distribution of apolipoprotein E allele were analyzed. Results : The cognitive function scores decreased with aging and the difference between baseline and the 2nd follow-up scores of the study increased with the age group. The incidence rate of cognitive impairment through an 8-year follow-up was 38.5% and higher in older age groups. Age was the only significant factor for incidence of cognitive impairment, but there was no significant association between apolipoprotein E genotype and incidence of cognitive impairment. Conclusions : The cognition of the elderly decreased with aging and the association of apolipoprotein E genotype with incidence of cognitive impairment was not significant in this study. To confirm the association between apolipoprotein E polymorphism and incidence of cognitive impairment further studies will be needed.

조위변동(潮位變動)으로 인한 호안제내(護岸堤內)의 침투(浸透)

김상규,Kim, Sang Kyu 대한토목학회 1985 대한토목학회논문집 Vol.5 No.3

포화(飽和) 및 비포화(非飽和) 흐름을 함께 적용할 수 있는 transient flow 방정식(方程式)을 사용하여 조위(潮位)의 상계(上界) 하강(下降)에 따른 호안제(護岸堤) 내(內) 수두(水頭의) 시간적(時間的) 변화(變化)를 구하였다. 계산(計算)은 FEM 기법(技法)을 써서 흙 속의 흐름 문제를 해석하도록 개발(開發)된 전산(電算)프로그램 FLUMP로 행 하였는데, 본(本) 연구(硏究)에서 조위상승시(潮位上昇時)에도 적용할 수 있도록 이것을 일부분(一部分) 보완(補完)하였다. 호안제(護岸堤)는 두 가지 재료(材料)로 구성된 것으로 보고 10m의 일정(一定)한 조차(潮差)로 인한 제체(제체) 내(內) 수두(水頭)의 시간적(時間j的) 변화(變化)를 최대 96 시간까지 계산하였다. 제체(堤體) 배면(背面)의 지하수위(地下水位)는 최저(最低) 조위(潮位)로부터 0 m, 5 m, 및 10 m의 위치에 있다고 가정하고 제체(堤體) 내(內) 수두(水頭)가 지하수위(地下水位)의 위치에 따라 어떻게 평형되어가는가 알아보았다. 해석결과(解析結果)에 의하여 조위(潮位) 상계(上界) 하강(下降)에 대응(對應)하여 제체(堤體) 내(內) 수두(水頭)도 변화(變化)하나 수두(水頭)의 변화진폭(變化振幅)은 위치마다 다르다는 것을 알게 되었다. 즉(卽), 제체(堤體)의 상류면(上流面) 지단(趾端)에서 수두(水頭)의 진폭(振幅)이 가장 크고 상류면(上流面)에서 제체(堤體) 내(內)로 멀어질수록 진폭(振幅)은 차츰 줄어들며, 어느 위치를 넘어서면 수두(水頭)는 조위변동(潮位變動)의 영향을 받음이 없이 제체(堤體) 배면(背面)의 지하수위(地下水位)에 상응(相應)하는 어떤 평형된 수두(水頭)를 향(向)하여 안정(安定)되어간다. 제체(堤體)가 일시(一時)에 축조되었다고 가정하면 96 시간이 경과하였을 때 제체(堤體) 내(內) 수두(水頭)는 안정(安定)된 위치로 대락(大略) 접근(接近)하였다. Using a saturated-unsaturated transient flow equation the change of hydraulic heads within a dike due to tidal fluctuation is investigated in this study. The calculation is done by the use of a software computer program called FLUMP, which is based on a FEM technique and useful to the analyses of unsaturated flow problems. Some of the program has been supplemented in this study for the application to the rise of a tide. It is assumed that a dike is composed of two materials, that the tide rises and falls with a constant amplitude of 10 meters, and that water tables are located at 0m, 5m, and lam from the minimum tidal level. For these conditions the hydraulic heads are calculated for 8 cycles(96 hours) of tidal changes. It is known from the analysis that the hydraulic heads change with tidal level in some extent and that the amplitudes of the head varies depending on the location within the dike: the maximum amplitude shows near the toe of the dike, the amplitude decreases with increasing distance from the upstream face, and beyond a certain location the heads are unaffected by the tidal differences. Assuming that the dike has been completed in a moment the hydraulic heads are nearly stabilized in 96 hours towards some constant values corresponding to a specified water table.

書院祭를 通해서 본 戰略的ㆍ操作的 父系親族集團

金相圭(Kim Sang-kyu) 동북아시아문화학회 2002 동북아시아문화학회 국제학술대회 발표자료집 Vol.- No.-

In this presentation, being aware of kin organizations in East Asia, we will examine from a new perspective the nature of Korean Mun Jung groups, which have been studied based on theories of family and kin, through a positive research on Do Dong Seo Won Ritual, referring to the archives of existing researches on Seo Won and Mun Jung groups. Seo Won Ritual, which has been preserved until now though its educational function was removed, can be positioned as a ground where social relationships among Mun Jungs are established in Korean local societies, beyond its traditional function as a place simply for family rituals (events). Thus, through a sociological anthropological analysis of Seo Won Ritual, we may be able to throw some light on previous findings in the areas of history, politics and education, and grasp the nature of Seo Won Ritual in Korean local society. On the other hand, Mun Jung in Korea can not be thought merely as an innate patrilineal kin group. Rather than that, it may be understood as an manipulative and strategic organization that exercise authority and influence on the local society, taking charge of social relationships with external entities (This fact is manifested particularly by Seo Won ritual services. Especially Mun Jung in higher social status is more active in manipulative and strategic activities. The characteristic of Do Dong Seo Won (Ritual) is that it has grand ritual services 4 times a year. In general, Seo Won ritual services occurred twice a year, which are Chunhyeong Ritual and Chuhyeong Ritual, in the past in Korean society, but now they vary depending on the condition (mainly the economic condition) of the Mun Jung that holds the actual control of management of Seo Won. It is thought as a strategic and manipulative ritual service in a patrilineal kin group that, in Do Dong Sea Won, before having Myohyeong Ritual Service for Kim Going Pil, who is the Ju Hyeong of the Seo Won, Myohyeong Ritual Service for "Yu", Kim Going Pil's father, is held first by the Mun Jung of Seoheung Kim. What are necessary for further researches are to compare Japanese Sin Sa Ritual and Chinese with Korean Seo Won Ritual that has the function of expanding and integrating local societies, and compare and analyze all related factors from individuals to states among Korea, China and Japan to make clear the cultural universality and particularity of the three countries.

전국(全國) 동결(凍結)깊이 분포(分布)와 동결깊이 및 동결지수(凍結指數)와의 상관관계(相關關係)

김상규,박상길,박방훈,Kim, Sang Kyu,Park, Sang Kil,Park, Bang Hun 대한토목학회 1990 대한토목학회논문집 Vol.10 No.2

국립 건설 시험소에서 1980년 부터 1989년에 이르기가지 10년 동안 전국에 걸쳐 동결(凍結)된 지반의 깊이를 조사하였다. 그 위치는 무작위(無作爲)로 선정하였으나 동결이 심한 지반에 대해 조사하도록 노력하였다. 조사지점의 동결토(凍結土)를 채취하여 미 공병단의 동결토(凍結土) 분류방법(分類方法)에 따라 분류하였다. 동결 깊이 조사자료를 근거로 하여 전국(全國) 최대(最大) 동결(凍結)깊이 선도(線圖)가 작성되었다. 한편, 기상자료를 이용하여 포장설계에 이용할 수 있도록 설계 동결지수선도를 작성하고, 1980년에 도로조사단에서 작성한 자료(資料)와 비교 분석하였다. 동결깊이는 공기동결지수의 3승근(乘根)에 비례하는 새로운 경험식을 제안(提案)하고 다른 경험식과 비교하였다. The National Construction Research Institute of Korea has measured the depth of the frozen ground covering all the areas of South Korea during ten years ranging through 1980. The measurements were made for the frozen ground at random but intended for the most frost-susceptible soils. The soils of the frozen ground were sampled and then classifide into four groups according to the frost design soil classification system suggested by the Corps of Engineers of the United States. The contours of the maximum depth of the frost penetration are drawn on a map with data collected during the ten years. Also isolines of the design frezing index are shown on an another map using the metorological information of 1980-1989 and compared whth those in vestigated in 1980 by Highway Survey Team of the Ministry of Construction, Korea. It is known that the maximum depth of the frost penetration is related to freezing index values. An empirical formula expressing the relation is suggsted, in which the depth is proportional to the one-third power of the air freezing index values.

Acrylamide가 인체상피세포의 발암화에 미치는 영향

김상규,김진욱,김진수,Kim, Sang-Kyu,Kim, Jin-Wook,Kim, Chin-Soo 대한구강악안면외과학회 2008 대한구강악안면외과학회지 Vol.34 No.6

Purpose Acrylamide is present in significant quantities in a wide range of commonly consumed human foods. Carcinogenic risk of acrylamide through the consumption of food is a great public concern and in controversy, but it is not properly addressed due to the lack of evidence in humans. While a plenty of data is available on the carcinogenicity in animal models, the studies in humans are limited. Thus, the present study attempted to examine the carcinogenic potentials of acrylamide on the human epithelial cell, which is the target cell origin of the most cancers. Material and method & Result 1. Acrylamide was not cytotoxic up to $100{\mu}M$ as measured by MTT and LDH assays, indicating a relatively low toxicity of this substance in human epithelial cells. 2. The parameters of neoplastic cellular transformation such as cell saturation density, soft-agar colony formation and cell aggregation were analyzed to examine the carcinogenic potential of acrylamide. 3. The neoplastic transformation was further increased with the co-treatment of TPA 4. Antioxidants blocked the generation of Reactive Oxygen Species(ROS) and the GSH depleting agent dramatically increased the ROS production. 5. mRNA levels of fibronectin following acrylamide exposure was increased in a dose-dependent manner, indicating a possible biomarker of acrylamide-induced cellular transformation. Conclusion The present study will provide a valuable basis to compare the interspecies differences in response to carcinogenic potentials of acrylamide. The data on the interspecies differences are essential element in human risk assessment. Thus, our results obtained from the human epithelial cells will contribute to improving the risk assessment of human neoplasm including oral cancer.