계산자의 사용법

이계희,Lee, Gye-Hui 한국전산구조공학회 2019 전산구조공학 Vol.32 No.2

간호학생이 내린 실습 영역별 간호진단 분류에 관한 일 연구

이계희 대구산업정보대학 1994 논문집 Vol.8 No.-

This Study classified the nursing diagnoses by student nurses according to clinical areas, using the reports summitted from Mar 8, to Nov 27, 1993 after their clinical practice, based on 72 NANDA nursing diagnoses so as to provide the data bases for the estabilishment of nursing diagnoses. The result were as follows : 1. The number of nursing diagnoses used in adult nursing was 340 and they showed the next frequency : Comfort, alteration in : pain(9.1%), which was most frequently used, Anxiety and Bowel elimination, alteration in : constipation(6.2% respectively), Hyperthermia(5.0%) and Health maintenance, alteration in(4.7%) 2. According to clinical area, the frequency distribution was Hyperthermia(7.9%), most frequently used, Health maintenance, alteration in(7.3%), and Comfort, alteration in : Pain(6.7%) in the internal ward ; Comfort, alteration in : pain(16.9%), most frequently used, Anxiety(10.6%), and Comfort, altered : chronic pain(6.7%) in the general surgical ward ; Sensory-perceptual alteration(12.9%), most frequently used, Bowel elimination, alteration in : constipation(9.8%), and Thermoregulation, ineffective(6.5%) in the neurosurgical ward ; Bowel elimination, alteration : constipation(16.3%), most frequentty used, Comfort, alteration in : pain and Anxiety(10.8% respectively) in the orthopedic surgical ward.

준정적 충돌해석을 통한 선박충돌방공호의 방호능력평가

이계희,Lee, Gye-Hee 한국전산구조공학회 2011 한국전산구조공학회논문집 Vol.24 No.6

본 연구에서는 방호공의 최대방호능력을 산정하기 위하여 선박충돌방호공과 선박을 수치적으로 모델링하고 준정적해석으로 충돌해석을 수행하였다. 방호공은 구조물의 비선형 거동과 지반의 지지효과 및 인발을 고려하여 모델링되었다. 충돌선박은 비선형거동이 집중되는 선수부분을 정밀하게 모델링하고 효율적인 해석을 위해 mass scaling기법을 사용하였다. 동일한 해석모델에 대하여 동적해석을 추가적으로 수행하여 두 해석방법의 차이점과 효율성을 평가하였다. 선박과 방호공의 에너지소산곡선을 바탕으로 충돌선박이 교량하부구조에 충돌력을 전달되는 시점을 추정하고, 이를 바탕으로 대상선박의 최대충돌허용속도를 산정하였다. 이러한 추정방법이 방호공의 에너지소산한계를 명확히 판단할 수 있어 공학적으로 효율적인 산정방법임을 보였다. In this study, the vessel collision protective structure and the vessel were modeled numerically and the quasi-static collision analysis was performed to evaluate the maximum protection capacity. In the modeling process of protective structure, the nonlinear behaviors of structure and the supporting conditions of ground including pull-out action were considered. In that of collision vessel, the bow of vessel was modeled precisely, because of the nonlinear behaviors were concentrated on it. For the efficient analysis, the mass scaling scheme was applied, also. To evaluate the differences and efficiency, the dynamic analyses were performed for the same model, additionally. Based on the obtained energy dissipation curves of the structure and the vessel, the moment that the collision force affected to the bridge substructures was determined and the maximum allowable collision velocity was evaluated. Because of the energy dissipation bound can be recognized clearly, this scheme can be used efficient in engineering work.

μ-GA를 이용한 원전 캐비닛구조물의 최적감쇠보강

이계희,하동호,Lee, Gye-Hee,Ha, Dong-Ho 한국지진공학회 2005 한국지진공학회논문집 Vol.9 No.1

The optimal seismic retrofitting of NPP(Nuclear Power Plant) cabinet structures that contain seismic category 1 relays was studied in this paper. During earthquake event, the failure modes of relays are not appeared in form of structural failure, but are appeared in form of contact chatter of relay. Therefore, the retrofitting of cabinet has to be aimed at the reducing of the structural response, such as acceleration. In this study, the optimal characteristic values of dampers were searched by ${\mu}$-GA (micro-Genetic Algorithm) scheme for several installation patterns. To keep accuracy and efficiency of analysis, the structural models of cabinet were considered as a frame structure. The responses of structure were obtained inform of acceleration response spectra derived from the results of nonlinear time history analysis including damping nonlinearity. The objective function of the optimum procedure was constructed based on the maximum ratio of maximum spectral value and target GERS (General Equipment Ruggedness Spectra). The results show the good improvements of fitness for adequate retrofitting pattern. Especially, the improvements of fitness were remarkable when the values of damping exponents are low. 본 논문에서는 원전내부의 내진범주 1급 계전기를 포함하고 있는 캐비닛 구조물의 최적내진보강에 대한 연구를 수행하였다. 지진시 계전기는 구조적인 파괴보다는 떨림에 의한 기능적 파괴가 발생한다. 이를 방지하기 위해서는 캐비닛구조물의 응답을 적정 수준이하로 감소시켜야 하므로 다양한 감쇠보강의 설치패턴에 따라 최적의 감쇠계수를 ${\mu}$-GA(micro-Genetic Algorithm)기법을 이용하여 산정하였다. 대상캐비닛 구조물은 해석의 정확도와 계산의 효율성을 만족시키기 위해 이용한 프레임구조로 모델링되었다. 구조물의 응답은 감쇠기의 비선형거동을 고려한 비선형 시간이력해석에 의해 얻어진 가속도응답스펙트럼으로 나타내었다. 목적함수는 구조물의 해석에서 얻어진 응답스펙트럼의 최대값과 목표 포괄기기내진력 스펙트럼 (GERS; General Equipment Ruggedness Spectra)의 최대응답비를 기초로 작성되었다. 해석결과 적절한 보강패턴을 선정한 경우 좋은 적합도의 향상을 보였으며 특히 감쇠지수의 값이 작은 경우 적합도의 개선효과가 뛰어났다.

박리를 고려한 지하박스구조물의 화재하중해석 I : 박리해석

이계희,최익창,Lee, Gye-Hee,Choi, Ik-Chang 한국전산구조공학회 2007 한국전산구조공학회논문집 Vol.20 No.4

본 연구에서는 전력구나 공동구와 같은 지하 콘크리트박스구조물의 화재발생시 온도분포와 박리거동에 대한 수치해석을 수행하였다. 해석에 사용된 온도장은 터널화재에 사용하는 화재곡선을 기본으로 하고 화재시 내부공간에 대한 열유체해석을 수행하여 온도분포를 결정하였다. 박리거동은 탈수화도를 따라 콘크리트의 온도가 기준값에 도달하였을때 발생하는 것으로 하였다. 이때 박리가 일어난 요소를 제거하고 경계조건과 요소망을 재생성하여 해석을 반복수행하였다. 3개의 화재 시나리오에 따라 해석을 수행하였고, 해석결과는 각 시나리오별로 타당한 박리거동을 보여주었다. 각 시나리오에 따른 구조물의 내하력은 본 논문의 2편에서 산정되었다. In this study, the numerical fire analysis for temperature distribution and spalling behavior of underground concrete box structures that contained lifelines, such as power cables and communication cables. The temperature field of inner space was assumed based on the fire curve with the thermal gradient obtained from CFD analysis. It was assumed that the spalling behaviors of concrete are occurred when the concrete temperature reached the threshold, as dehydration degree. In this case, the elements correspond to spalling parts were removed and the analysis model were updated. Three fire scenarios were analyzed and the results were showed adequate spalling behavior. The bearing capacities of the box structures would be estimated in the companion paper.

비동질 반무한 평면에서의 비례경계유한요소법

이계희,Lee, Gye-Hee 한국전산구조공학회 2007 한국전산구조공학회논문집 Vol.20 No.2

본 논문에서는 비동질 반무한 평면에 대한 비례경계유한요소법의 식을 유도하고 수치예제를 해석하였다. 비례경계유한 요소법은 편미분 방정식을 경계방향으로는 유한요소와 같은 근사를 통해서 약화시키고 방사방향으로는 정확해를 사용하는 반 해석적인 방법으로, 방사방향으로 멱함수를 따라 탄성계수가 변화되는 반무한 평면에 대해서 관계식을 가상일의 원리에 근거하여 새로이 유도하였다. 이 과정에서 반무한평면의 거동이 Euler-Cauchy방정식을 따름을 보이고, 기존의 동질 반무한평면의 해석시 도입되던 로그모드가 비동질 반무한 평면의 해석에는 유효하지 않음을 보였다. 수치예제를 통하여 유도된 식이 타당한 거동을 보임을 증명하고 이 접근법이 실제 공학적 문제의 해결에 있어서 유용함을 보였다. In this paper, the equations of the scaled boundary finite element method are derived for non-homogeneous half plane and analyzed numerically In the scaled boundary finite element method, partial differential equations are weaken in the circumferential direction by approximation scheme such as the finite element method, and the radial direction of equations remain in analytical form. The scaled boundary equations of non-homogeneous half plane, its elastic modulus varies as power function, are newly derived by the virtual work theory. It is shown that the governing equation of this problem is the Euler-Cauchy equation, therefore, the logarithm mode used in the half plane problem is not valid in this problem. Two numerical examples are analysed for the verification and the feasibility.

지역사회 알레르기 질환의 역학적 연구

이계희,Lee, Kye-Hee 한국지역사회간호학회 2000 지역사회간호학회지 Vol.11 No.1

In order to find out the sex- and age-related prevalence rate of allergic diseases in the community. as well as the causes of those diseases. questionnaires were given to 2.415 subjects (1.206 males and 1.209 females) from May to June. 1998. As a second stage. skin tests were given to 452 of the original subjects between July and August. 1998. Finally. from March to November 1999. the results of the tests were compared with those of other countries to make a comparative analysis of epidemiological research on allergic diseases. The results of this study were as follows: The frequency of allergic symptoms by sex was 50.1% in males and 56.7% in females. respectively, which displayed significant difference between males and females(p<.01). By age, the frequency of allergic symptoms in males was highest for those under the age of 9 at 60.6%, whereas in females the highest frequency was between the ages of 30 to 39 at 75.1 %. The relationship between economic level of the subjects and their frequency of allergic diseases showed significant difference (P<.05). There was a high degree of correlation between family history and the frequency of allergic diseases(P<.01). In allergic symptoms, the highest prevalence in both males and females occurred with urticaria, itch and skin rash (33.6% with males and 38.0% with females). Rhinitis, nasal blocking and sneezing had the second highest frequency in both sexes (11.8% of males and 14.0% of females). With regard to the causes of allergic symptoms among the people with allergies, the rate in males was 30.1% in food. 25.0% in pollen, and among females the rate was 30.7% in food, 26.6% in pollen. The frequency of food allergies by sex was 25.6% in males and 25.8% in females, with little difference between males and females, and by age, males of the ages between 40 to 49 and females of the ages between 30 and 39 showed the highest frequency, 31.8% and 32.6% respectively. Among 585 people with food allergies, the sympoms occurring with the allergy in males were 81.5% with urticaria, itch and skin rash. 5.9% with diarrhea and stomachache, and 5.2% with rhinitis, nasal blocking and sneezing. Among females with food allergies, the symptoms were 82.6% with urticaria, itch, skin rash, 9.1% with diarrhea and stomachache, and 4.7% with rhinitis, nasal blocking and sneezing. The type of food most often causing allergy in males was mackerel (6.6%) and females peaches (7.4%). In respect to a positive rate in the skin test by sex, of the 379 males taking the skin test, 21.4% were positive for allergies, whereas 14.7% of the 346 females tested were positive. Among food items found to cause positive allergic reactions, hops had the highest frequency in males (58.9%) and whole eggs had the greatest effect on females (36.4%). The estimated prevalence of food allergies in terms of skin tests was 5.0% of 1.206 males and 3.6% of 1.209 females. In the estimated frequency of food allergy by age group, males of the ages between 40 and 49 and females of the ages from 30 to 39 had the highest rate (6.5% with males and 4.5% with females). In a comparative analysis of epidemiological research on allergic diseases by country group, allergic diseases occurred in 18-50% of each population studied, and the occurrence of allergic diseases when categorized according to symptoms displayed the following as such: allergic rhinitis (3.8-52%), allergic asthma (1.6-17%), and atopy dermatitis (0.33-20.4%). The prevalence of food-related allergies was 6.6-64.9% and the foods causing allergies frequently included milk, eggs, eggs, peanuts, fish, etc.

경계반력법에 의한 비선형 SSI 해석을 위한 선형 FE 해석모델 검증

이계희,홍관영,이은행,김재민,Lee, Gye Hee,Hong, Kwan Young,Lee, Eun Haeng,Kim, Jae Min 한국전산구조공학회 2014 한국전산구조공학회논문집 Vol.27 No.2

이 논문에서는 경계반력법을 이용한 비선형 지반-구조물 상호작용 해석을 위해 LS-DYNA나 MIDAS/Civil 등의 유한요소해석 프로그램과 연계하는 방법을 제시하였다. 경계반력법 적용시 유한요소프로그램에서 구조물과 지반은 선형 또는 비선형 유한요소를 이용하여 모델링하였다. 유한요소의 해석모델 외부의 무한영역으로 전달되는 탄성파를 최대한 흡수하기위해 유한요소 모델의 외측에 LS-DYNA의 경우에는 PML(Perfectly Matched Layer) 요소를, MIDAS/Civil의 경우에는 점성감쇠-스프링 요소를 적용하였다. 비선형 유한요소는 구조물영역에만 적용되는 것으로 가정하였다. 이 연구에서는 입사지진파에 의한 경계반력은 KIESSI-3D 프로그램을 이용하여 계산하였다. 선형 지반-구조물 상호작용 문제에 대해 일반적인 KIESSI-3D의 해석결과와 BRM해석결과를 비교하여 제시된 방법의 효율성을 제시하였다. 또한 수치적 비교를 통해 비선형 구조에 대해 보수적인 응답을 보이는 선형 SSI문제에 대하여 얻은 경계반력이 비선형 지반-구조물 상호작용해석에 효과적으로 적용 가능함을 알 수 있었다. In this paper, a coupling scheme for applying finite element analysis(FEA) programs, such as, LS-DYNA and MIDAS/Civil, to a nonlinear soil structure interaction analysis by the boundary reaction method(BRM) is presented. With the FEA programs, the structure and soil media are discretized by linear or nonlinear finite elements. To absorb the outgoing elastic waves to unbounded soil region as much as possible, the PML elements and viscous-spring elements are used at the outer FE boundary, in the LS-DYNA model and in MIDAS/Civil model, respectively. It is also assumed that all the nonlinear elements in the problem are limited to structural region. In this study, the boundary reaction forces for the use in the BRM are calculated using the KIESSI-3D program by solving soil-foundation interaction problem subjected to incident seismic waves. The effectiveness of the proposed approach is demonstrated with a linear SSI seismic analysis problem by comparing the BRM solution with the conventional SSI solution. Numerical comparison indicates that the BRM can effectively be applied to a nonlinear soil-structure analysis if motions at the foundation obtained by the BRM for a linear SSI problem excluding the nonlinear structure is conservative.

비동질 탄성 무한공간에 대한 비례경계유한요소법의 동적강도행렬

이계희,Lee, Gye-Hee 한국전산구조공학회 2010 한국전산구조공학회논문집 Vol.23 No.2

In this paper, the dynamic stiffness of scaled boundary finite element method(SBFEM) was analytically derived to represent the non-homogeneous space. The non-homogeneous parameters were introduced as an expotential value of power function which denoted the non-homogeneous properties of analysis domain. The dynamic stiffness of analysis domain was asymptotically expanded in frequency domain, and the coefficients of polynomial series were determined to satify the radiational condition. To verify the derived dynamic stiffness of domain, the numerical analysis of the typical problems which have the analytical solution were performed as various non-homogeneous parameters. As results, the derived dynamic stiffness adequatlly represent the features of the non-homogeneous space. 본 논문에서는 비동질 탄성무한공간에 대한 비례경계유한요소법의 동적강도행렬을 해석적으로 유도하였다. 해석영역의 비동질성은 비동질파라메터를 지수로 하는 멱함수로 고려하였다. 동적강도행렬은 진동수영역에서 다항식으로 점근전개한 후, 방사조건을 만족시키도록 하여 각 다항식의 계수를 구하는 과정을 통하여 유도되었다. 얻어진 동적강도행렬의 타당성을 검증하기 위해 정확해가 알려져 있는 대표적인 문제에 대하여 비동질파라메터의 값을 변화시키면서 수치해석을 수행하였다. 그 결과 유도된 동적강도행렬이 비동질공간에 대한 특성을 적절하게 반영하는 것으로 나타났다.

Infinite Element for the Scaled Boundary Analysis of Initial Valued on-Homogeneous Elastic Half Space

이계희,Lee, Gye-Hee,Deeks, Andrew J. Computational Structural Engineering Institute of 2008 한국전산구조공학회논문집 Vol.21 No.2

본 논문에서는 초기값을 갖는 비동질 반무한 평면문제를 비례경계유한요소법으로 해석하기 위하여 무한요소를 이 해석법에 도입하였다. 초기값을 갖는 반무한 평면의 자유면은 비례경계좌표계의 원주방향의 좌표를 이용하여 모델링하였고 무한요소는 이 자유면이 나타내는 무한한 영역을 모사하기 위해 사용되었다. 반무한 평면의 물성치(탄성계수)에 대한 초기값은 비례중심의 위치와 비례경계좌표계에서의 반지름 멱함수를 이용하여 나타내었다. 사상형 무한요소를 사용하여 일관된 정식화가 가능하였고, 제안된 해석법에 대한 적용성과 성능을 두 수치예제를 통하여 보였다. In this paper, to analyze the initial valued non-homogeneous elastic half space by the scaled boundary analysis, the infinite element approach was introduced. The free surface of the initial valued non-homogeneous elastic half space was modeled as a circumferential direction of boundary scaled boundary coordinate. The infinite element was used to represent the infinite length of the free surface. The initial value of material property(elastic modulus) was considered by the combination of the position of the scaling center and the power function of the radial direction. By use of the mapping type infinite element, the consistent elements formulation could be available. The performance and the feasibility of proposed approach are examined by two numerical examples.