간극내 외팔보 운동의 실험해석

최연선,김경래 成均館大學校 科學技術硏究所 1995 論文集 Vol.46 No.1

Many mechenical systems experience intermittent motion of contact and separation due to the existence of clearances which may cause from manufacturing tolerances, wear, or backlash. The complex nonlinear dynamic responses within such systems can produce proper functioning or loss of performance as like wear, fretting, fatigue, as well as high noise level. In this study, the dynamic responses of a cantilever beam motion in clearance are measured with a simplified experimental set-up and the experimental results are compared with those of numerical harmonic balance method and those of numerical intergration. The results show that the cantilever motion in clearance can be modeled as a piecewise-linear oscillator, which characterizes nonlinear system. As a result, the nonlinear responses of jump phenomenon and higher harmonics are investigated experimentally and analytically. Also, the effects of the variation on system parameter were studied.

흰쥐 십이지장 점막의 Polyamine 대사, [^(14)C]Spermine 단백 결합능 및 [³H]Thymidine DNA 섭취에 대한 Calcitriol과 Prednisolone의 상호작용

최상현,이영재,정휘정,김형건,신경호,천연숙,전보권 고려대학교 의과대학 1997 고려대 의대 잡지 Vol.34 No.1

Calcitriol has been shown to induce the duodenal synthesis of the spermine-binding protein. and hydrocortisone was reported to increase the intestinal polyamine contents. This study examined whether prednisolone might enhance or reduce the calcitriol effects on the polyamine contents, [^(14)C]spermine-protein binding activity, and [^(3)H] thymidine DNA synthesis of the rat duodenum. The mucosal contents of putrescine. spermidine. and spermine were increased by 198.8%, 84.0%, and 78.3%, respectively, within 6 hours after calcitriol. 5 ㎍/kg (CT) and fell down to the control values at 12 hours. And prednisolone. 10 mg/kg (PD) also increased the polyamine contents in similar patterns. They did not counteract each other in the polyamine metabolism. CT increased the [^(14)C]spermine-binding activity of the cytosol protein fraction from the duodenal mucosa by 71.1%. But PD increased the binding activity by 28.0% and did not affect the CT-induced increase. CT increased the [^(3)H]thymidine DNA synthesis of the duodenal mucosa by 42.3%. but PD reduced it slightly. The CT-dependent increase of the synthesis was significantly inhibited by PD. These results suggested that the inhibitory effect of glucocorticoids on the vitamin D dependent increases of the duodenal calcium absorption and mucosal proliferation seems not to be associated with the metabolic changes of polyamines in the duodenal mucosa.

장구균의 동정에 대한 PCR 방법의 유용성

최연화,이영선,김홍빈,김치경,김봉수 대한감염학회 2001 감염 Vol.33 No.2

Background : Enterococci are important cause of nosocomial infections. Recently, vancomycin-resistant enterococci (VRE) has been increasingly reported as significant nosocomial pathogens. Therefore, accurate identification of enterococcal species is a prerequisite step for the appropriate antibiotic treatment and epidemiologic surveillance. We wanted to know the usefulness of PCR method compared with Vitek automatic identification system. Methods : Totally 105 isolates were identified on the species level by Vitek (GPI card and software version R06.1), methyl-α -D-glucopyranoside test, and PCR methods. Results : Among 105 enterococcal isolates, 59 were identified as E. faecium, 11 E. faecalis, 6 E. gallinarum by Vitek. But 29 isolates (28%) were unidentified. Subsequently all of these isolates were analyzed by PCR, the results of which were as follows : 17 E. faecium, 5 E. casseliflavus, 7 E. gallinarum. Two isolates identified as E. gallinarum by Vitek were reidentified as E. casseliflavus by PCR and other methods far phenotypic characterization. Conclusoin : PCR method was more accurate and sensitive than Vitek for the identification of enterococci species. (Korean J Infect Dis 33:123∼127, 2001)

영아에서 발생한 골수섬유증 1례

최성민,이동석,권경배,김두권,김나연,원유흥,이준희,권영무 동국대학교 경주대학 1996 東國論集 Vol.15 No.-

특발성 골수섬유증은 만성 골수증식성 질환의 하나로 말초혈액도말에서 백적아구증, 부동변형적혈구 눈물방울세포 소견을 보이며, 골수 생검상 망상 섬유와 교원섬유로 구성된 섬유조직이 증가하는 골수의 섬유화 소견을 보이며, 골수외 조혈작용으로 인한 대상적 비장·간장 종대를 특징으로 하는 소아에서는 극히 드문 질환이다. 저자들은 본원에 복부종괴와 안면창백으로 입원하였던 8개월된 남아에서 임상증상, 말초혈액검사, 골수생검에서 특발성 골수섬유증으로 진단되어 Methylprednisolone 대량 정주 요법으로 치료하였으나 진단7개월만에 패혈증과 심부전으로 사망했던 1례를 경험하였기에 문헌고찰과 함께 보고하는 바이다. Idiopathic myelofibrosis is a chronic myeloproliferative disorder characterized by anemia, leukoerythroblastosis, anisopoikilocytosis, tear-drop cell, extramedullary hematopoiesis with hepatosplenomegaly and varying degrees of myelofibrosis of bone marrow. The mean age is about 60 years, and pediatric cases are rare. We experienced a case of idiopathic myelofibrosis in a 8 months old male who was presented with pallor, huge splenomegaly, leukoerythroblastosis in peripheral blood, myelofibrosis in bone marrow biopsy. We presented a case of idiopathic myelofibrosis with brief review of the literatures.

노인의 영적 간호요구

최미혜,김경희,김귀옥,김기숙,김수강,김정신,김춘숙,노흥진,박지연,성혜연,오명선,이선희,이원옥,이윤영,이현수,장명재,차혜경,채정선,홍상희 중앙대학교 의과대학 간호학과 간호과학연구소 2001 중앙간호논문집 Vol.5 No.1

This study was designed to exam the aged's needs for spiritual nursing care. The purpose was to serve as a basis for the development of spiritual nursing practice. The major findings are as follows : 1. The degree of needs for spiritual nursing care as area was that needs of love and relationship mean 22.0, needs of meaning and object mean 28.2, needs of forgiving mean 13.5. Total needs for spiritual nursing care mean 63.7, which was on the upper middle level. The needs of meaning and object was rated highest. 2. Among the general characteristics of the subjects, needs of love and relatiohship wasn't significanlty different. 3. Among the general characteristics of the subjects, needs of meaning and object was significantly different according to two factors : age(F=7.260, p=0.001), religion(F=5.275, p=0.001). Higher needs of meaning and object was possessed by the older than the younger, by the one who have religion than the other. 4. Among the general characteristics of the subjects, four factors made a significantly difference to needs of forgiving : sex(t=-2.851, p=0.006), age(F=8.201, p=0.001), religion(F=6.928, p=0.000), disease(t=2.327, p=0.024). Higher needs of forgiving was possessed by man than woman, by the older than the younger, by the one who have religion than the other, by the one who have disease than the other.

조직구성 수성망상증 2예

최연수,박일,죄희충,김원식,양태영,허경,안기완,정춘해 조선대학교 1993 The Medical Journal of Chosun University Vol.18 No.2

Histiocytic medullary reticulosis (HMR) is a malignant noeplastic process, with tumor cells belonging to the histiomonocytic line, and originally described by Scott and Robb-Smith in 1939 characterized by its acute onset, progression to death within a few months and its clinical features are fever, lymphadenopathy, hepatosplenomegaly, jaundice, and purpura common laboratory findings are characterized by severe anemia, leukopenia, thrombocytopenia and histologically by systemic progressive invasion of morphologically atypical histiocytes or of their precursor. 61 and 37-year-old males were admitted with camplaints of high fever and chilling sensation and were treated by cyclophosphamide, vincristine, prednison and antiobiotics, but patients all died 17 and 14 days after admission due to probably sepsis and respiratory failure.

비만을 동반한 위암 환자에서 두 병을 같이 수술 치료한 경험(증례)

최경현,윤기영,문형환,신연명,서경원,안수미,송윤미,석정희,정경연,이은하 고신대학교의과대학 2008 고신대학교 의과대학 학술지 Vol.23 No.3

Obesity is growing problem in Korea. We had a case of bariatric surgery during gastric cancer operation. Patient was 29 year old Korean lady with early gastric cancer located in the lesser curvature side of the middle 1/3 of the stomach. Her body weight was 89 kg, height 163 cm, and thus body mass index was 33.5 kg/m2. Preoperative blood pressure was 130/90 mmHg, hemoglobin 12.9 g/dL, total lymphocyte count 3,280/mL, serum albumin 4.3 g/dL, CEA 1.1 ng/mL, CA 19-9 9.1 ng/mL, and alpha fetoprotein 2 ng/mL. Another associated disease was right thyroid follicular neoplasm. The chest X-ray was normal. After IM injection of 2,500 units of heparin 30 minutes before the induction of general anesthesia, she received curative subtotal gastrectomy and Roux en Y gastrojejunostomy when a malabsorption loop of 120 cm jejunum was incorporated between the Treitz ligament and the end to side jejuno-jejunostmy site at May 29th 2006. Her postoperative course was uneventful except a minor wound seroma and the elevations of serum amylase(up to 4 folds) and lipase(up to 2 folds). She lost her body weight 9 kg in 5th, 21 kg in 7th, and 27 kg in 10th postoperative months to became 61.5 kg. On follow up exams in July 2008, she gained 4 kg to overcome her weakness and fatigue. From the above result, the incorporation of a malabsorption loop during reconstruction phase of gastric cancer operation was a good option for obese gastric cancer patients especially in cases of early gastric cancer.

저수축형 폴리머 콘크리트의 제조 및 물리·역학적 특성

연규석,이윤수,최동순,정경현,황진하 강원대학교 부설 석재복합신소재 제품연구센터 2000 석재연 논문집 Vol.5 No.-

본 연구에서는 폴리머 콘크리트의 수축저감을 목적으로 수지량, 수축저감제함량과 S/a 비등을 변화시켜 경화수축의 변화와 강도 특성을 실험적으로 구명하였다. 경화수축량은 수치량이 105%일 때 보다 11.5%일 때, 즉 수지량이 증가할수록 커짐을 알 수 있었다. 수축저감제의 첨가에 따른 경화수축량은 감소함을 알 수 있었다. B10.5-SR10일 경우 수축저감제가 첨가되지 않았을 때 보다 약 30%, B10.5-SR20 일 경우 약 53%, B11.5-SR10일 경우 약 31%, B11.5-SR20 일 경우 약 47% 정도의 수축저감의 효과를 볼 수 있었다. S/a 비에 따른 경화 수축챨ㅇ은 S/a 60일 때 가장 적은 값을 보였으며, S/a 50, S/a 40 일때는 S/a60 일 때 가장 적은 값을 보였으며, S/a 50, S/a 40일 때는 S/a 60일 때 보다 각각 10%, 30% 정도 수축량이 증가함을 알 수 있었다. 압축 및 휨 강도특성은 수지량이 증가할수록 높아지고, 수축저감제의 첨가량이 증가할수록 낮아짐을 알 수 있었다. S/a 비에 따른 강도 특성은 압축강도와 휨강도 모두 S/a 비가 60일 때 가장 큰 값을 보였으며, S/a 비가 50,40 순으로 감소하였다. Many different polymer based concrete materials are known today, but the large setting or hardening shrinkage of polymer concrete is a problem to overcome in their practical applications. The setting shrinkage reaches about five to ten times the drying shrinkage of ordinary cement concrete, i.e, 50 to 60 ×10^4. This paper deals with a reduction in the hardening shrinkage of unsaturated polyester resin concrete which is treated with respect to shrinkage-reducing agent content, S/a ratio and catalyst content, and tested for length change during hardening, and flexural and compressive strengths. It is shown that the change of shrinkage-reducing agent content and S/a ration the length change of the unsaturated polyester resin concrete during hardening.

FDTD Modeling for the Accurate Electromagnetic Wave Analysis of Graphene

Yeon‑Hwa Kim,Hongjin Choi,Jeahoon Cho,Kyung‑Young Jung 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.3

We develop a fnite-diference time-domain (FDTD) method suitable for the electromagnetic (EM) analysis of graphene. In this work, we employ the modifed Lorentz model for dispersion modeling, the two-dimensional (2-D) sheet model for geometrical modeling, and the complex-frequency-shifted (CFS)-perfectly matched layer (PML) for the absorbing boundary condition. In specifc, the accurate complex-conjugate pole-residue (CCPR) dispersion model is frst adapted for the electrical modeling of graphene by using the robust vector ftting. Next, the CCPR parameters are converted to the modifed Lorentz parameters and then the modifed Lorentz-based dispersive FDTD formulation is used to enhance the computational efciency. In FDTD cell modeling, the 2-D sheet cells are allocated for graphene rather than the conventional FDTD cell-based modeling. Finally, CFS-PML are employed for terminating the computational domain to avoid the late-time instability. The presented FDTD approach is validated in numerical examples for graphene-based parallel plate waveguides.

지역적 특성을 고려한 보육시설모형에 관한 연구

최경순,황연숙,정지영 신라대학교 자연과학연구소 1999 自然科學論文集 Vol.6 No.-

This study aims to grasp the present condition of nurseries, to investigate and analyse case studies, to suggest standards and reform measures, and based on these, to produce basic information for the formation of an architectural spatial model. Data were collected through questionnaire survey including observations and interviews. The sample consisted of 82 Child Care Centers. The data were analized by using SPSS-PC program. The major findings were as follows : (1) The facility and equipments in the child care centers were insufficient for children's development. (2) Most of child care centers are not in the desirable Interior environment. To enhance the quality of child care centers, the physical interior environment of child care centers should be influence on the development of child. (3) Functional spaces should be organized to support the child' behavior. Multi-purposed room should be provide to encourage and adapt to variety of large-muscle activities. (4) Interior findings looks too monotonous and do not have characteristics. Natural materials, various colors and patterns are recommendable. Furniture should be designed to meet the functions of flexibility, mobility, and security.