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.

冬蟲夏草의 抗轉移와 免疫增進에 關한 硏究

최우진,유화승,이용연,서상훈,조정효,이연월,손창규,조종관 대전대학교 한방병원 2000 惠和醫學 Vol.9 No.2

This experimental study was carried out to evaluate the effects of Cordiceps sinensis on the antimetastasis and immune activity. In order to investigate the effect of Cordiceps sinensis, the followings were performed; Cytotoxicity, inhibition of MMP-2 & MMP-9 gene expression, fraction of CD4+, CD8+, CD19+ in splenic cell, the moprphological change of splenic cells, gene expression of IL-12(p35), IL-12(p40), IFN-?? and splenic cell proliferation by CS-E. The results were obtained as follows. 1. CS-E did not present cytotoxic effect on L+14, B16-F10 melanoma cells and HMCB. 2. CS-E inhibited MMP-2 and MMP-9 gene expression more effectively compared with control group. 3. CS-E inhibited invasion of B16-F10 melanoma cells more effectively compared with control group. 4. CS-E helped CD4+, CD8+, CD19+ expression more effectively compared with control group. 5. CS-E activated phagocytic cells in spleen more effectively compared with control group. 6. CS-E helped IL-12(p35), IL-12(p40), IFN-?? gene expression in splenic cell more effectively compared with control group. 7. CS-E activated splenic cell proliferation more effectively compared with control group. From above findings, it is suggested that CS-E is able to inhibit metastasis of cancer and activate immune response system.

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)

일부 지역 노인의 건강증진 생활양식에 관한 연구

최연희,김연화 韓國保健敎育.健康增進學會 2001 보건교육건강증진학회지 Vol.18 No.3

This study was done describe health promoting lifestyle and to determine affecting factors in elderly based on the health promoting behaviors. The specific purpose of this study was to examine the relationships of life satisfaction, self-esteem and the demographic characteristics to health promoting lifestyle and to determine causal factors affecting the elderly. The subjects were a volunteer sample of 200 elderly in Kyungsan city. The instruments for this study were Health Promoting Lifestyle Profile(47 items), Life Satisfaction Scale(20 items) and Self-Esteem Scale(10 items). Frequency, percentage, t-test, ANOVA, Pearson's correlation coefficient and stepwise multiple regression technique with SAS program were used to analyze the data. The results of the study are as follows; 1)The average item score for the health promoting lifestyle was 3.3; the highest score on the subscale was self-actualization(M=3.5) with the lowest being exercise(M=2.9) 2)Health promoting lifestyle was significantly different according to marital status and religion. 3)All of the subscales on health promoting lifestyle were positively related to life satisfaction(r=0.534, p<0.001) and self-esteem(r=0.608, p<0.001). The life satisfaction was positively related to self-esteem(r=0.593, p<0.001). 4)Life satisfaction, self-esteem and marital status explained 28.04% of the variance for the total health promoting lifestyle. The results of this study show that life satisfaction, self-esteem and marital status predicted the health promoting lifestyle of the elderly. So health promoting programs that Increase life satisfaction and self-esteem should be developed to promote a healthy lifestyle of the elderly.

영아보육 일과에 나타난 질적 보육의 장애요인 분석

유연화,최경애,이정란 경복대학 2004 京福論叢 Vol.8 No.-

본 연구는 질적 연구를 통해 영아보육일과에 나타난 질적 보육의 장애요인을 분석함으로써 우리나라 영아보육 현장의 생태학적 특성을 이해하는데 목적이 있다. 보육시설의 질적 수준과 관련된 생태적 특성을 분석하기 위해 서울·경기 지역의 9개 보육시설을 참여관찰하고 영아반 교사와 시설장을 심층 면접하였다. 연구 결과, 협소한 보육실 등 물리적 환경의 열악함, 영아기 프로그램에 대한 이해 및 영아에게 적합한 교수전략의 부족, 지나치게 집단적인 교육과정 운영 및 일과지도, 비위생적인 건강관리태도, 영아용 실외놀이 환경의 부족, 보육교사의 열악한 근무 여건, 조기 학습에 대한 학부모의 압력 등이 관찰대상 영아보육 프로그램의 질을 저하시키는 장애요인으로 지적되었다. The purpose of this study is to understand the ecological characteristics of infant/toddler care program by analyzing major factors of barriers about the quality of infant/toddler care center. The main research consisted of the qualitative research, and 9 infant/toddler centers locate in Seoul and Gyeong-gi province. As findings of research, It pointed out some problems of infant/toddler care program which were observing target. It's problems were 1)lack of physical environment, specially small-crowded room, 2)lack of understand on the developmentally appropriate practice and instruction for infant/toddler care, 3)excessive grouping of activity and care, 4)unsuitable attitude of health care, 5)lack of out door environment for infant/toddler, 6)bad working condition of teachers, 7)negative attitude and pressure of parents toward ealy learning.

抗癌丹을 投與한 大腸癌 患者 83例에 대한 臨床報告

이용연,서상훈,유화승,최우진,조정효,이연월,손창규,조종관 대한한방종양학회 2000 대한한방종양학회지 Vol.6 No.1

Climical studies were carried out 83 cases of patients with colorectal cancer treated bv Hangamdan(抗癌丹) from January lth 1998 to September 30th 2000. The results were summarized as follows; 1. Distribution of those attached by colorectal cancer, by sex, showed that Male is more then Female, by age, showed that the numbber of fifties is majorith. 2. distribution of diagnostic stage, in descending order; stage Ⅲ(53%, top), stagew Ⅵ(45.8%). 3. The effects of maintenance and improvement in the symptoms with traditional oriental therapy(83.3%) and combined treatment of westem and oriental therapy(92.1%)were boserved. The effects of the symptoms were as folows: diarrhea(37.3%),abdominal pain (25.3%), general body weakness(22.9%), nausea(20.5%) and etc. in orders. 4. Analysis of hematology attached by colorectal cancer, maintenance and increasing of WBC(89.9%), RBC(74.7%), Hgb(81.1%), Platelet(92.4%) were Observed. After taken Hangamdan, the satety of the liver and kidney were as follows; maintenance and decreasting of AST(85.9%), ALT(94.8%) , GTP(87.5%), Creatinine(90.9%) were observed. 5. of IL-12 and IFN-λ attached by colorectal cancer, increasing of IL-12(53.3%), IFN-λ(80%) were observedl. 6. Analysis of QOL attached by colorectal cancer, maintenance and improvement of combined treatment of western and oniental therapy(89.6%), traditional oriental therapy(83.3%) were observed. 7. Analysis of survival in patients with Ⅳ stage of colorectal cancer, above 7 months(18.4%), 12 months(65.8%). 8. Analysis of antitumor effects, maintenance of traditional oriental therapy(83.3%) and maintenance and improvement of combined treatment of western and oriental therapy(80.5%) were observed. Analysis of tumor marker attached by colorectal cancer, maintenance and decreasing of CEA(78.8%) were boserved 9. Analysis of curative valuation, maintenance and improvement of traditional oriental therapy(83.3%), combined treatment of westem and oriental therapy(72.7%) were observed.

西歐 代替醫學의 癌 治療에 關한 硏究

兪和承,李容淵,徐祥熏,崔宇鎭,曺政孝,李淵月,孫彰奎,趙鍾寬 대한한방종양학회 2000 대한한방종양학회지 Vol.6 No.1

At here, we investigated the historical background, current stage, and concrete therapies of altematives in cancer therapy. We obatined the conclusion below. 1. Alternative medicine(AM) is a unothodoxial medical physiology, medical practice or intervension that overcome the side effects. faults, limits of coventional medicine. 2. Recentely, as emerging New-age movement, collgpse of Decarte's mecanical cosmology, and emphasis on patient rights, the interest of AM is increased, and foreign & domestic use rates of AM are risen. 3. After coventional medicine in cancer therapies tha depends on poerations, radiations, and chemotherapy is bounded, Altematives in cancer therapy are rapidly developed, and the majority of users are often considered satisfactory. 4. Alternatives in cancer therapy are classified six boundaries; Diet and Nutrition, MInd-body Technique, Integrated System, Pharmacologic and Biologictreatments, Immuno Enhanced Therapy, Immuno Enthaced Therapy, Natural and herbal medicine. 5. Looking at contents of Alternatives in cancer therapy, we get to know most of them are similar to the treatment of oriental medicine in holistic method, therapy, philosophy. If we synthesize the alternative medicine's treatment mentioned above and investigate it with oriental medical viewpoint, that may help us approach the conquest of cancer and improve the rate of cure. that may help us approach the conquest of cancer and improve the rate of cure. 6. It is certain that foreign AM will be imported reversely, and we must prepare for rebuilding of Korean traditional AM systemically, investing for activity positively, making national policy for medical system.

보육실습교사가 경험한 실습유형에 따른 보육실습실태

유연화,최경애,오애순 한국영유아보육학회 2004 한국영유아보육학 Vol.0 No.37

The purpose of this study is to analyze the practice areas and contents of student teaching program in child care centers, in which student teachers investigated the sort of practice activities according to have their experience during their practice period. This study was surveyed 324 under-graduate students who finished in child care center located in Seoul and Kyunggido. 349 questionsheets had distributed, and 324 respondents had answered it, that were analyzed with T-test, ANOVA, χ². The finding of this study were as follows: First, student teachers took practice average 9 hours and 58 minutes for a day, and they worked classroom for 80% of the practice time. Practicing Student teachers of 66.7% carried only in one classroom and others were rotated from a classroom to another. Second, student teachers had average 7.72% free play activities and 9.47% group activities. Private child care centers took more free play activities(arts, books, music area) and group activities(literature, music activities) than public. Third, almost student teachers assisted to children in snack and lunch every day or 3-4 times in routine practice. Forth, It was presented that student teachers were not coached by their instructor about charge of business practice. Fifth, It showed that student teachers used to participate classroomcleaning and teaching materials-arrangement from "participation degree of miscellaneous task" almost in everyday.

혈액에서 분리된 Extended-Spectrum Cephalosporin 내성 Enterobacter cloacae에서 Plasmid-Mediated Quinolone Resistance 유전자의 분포 및 Fluoroquinolone 감수성 양상

김연재,서미란,김지은,최은화,이환종,배현주 대한감염학회 2009 감염과 화학요법 Vol.41 No.5

Background : Extended-spectrum cephalosporins (ESCs)-resistant Enterobacter cloacae is one of the pathogens of nosocomial infection the incidence of which is on the rise. Moreover, plasmid-mediated quinolone resistance genes (PMQR genes) that reduce quinolone sensitivity have been shown to be widely distributed among clinical isolates of Enterobacteriaceae. This study was carried out to observe the distribution of PMQR genes in clinical isolates of E. cloacae resistant to ESCs. Materials and Methods : Fourty-three ESCs-resistant E. cloacae strains from the blood collected during the span of 7 years, from 1994 to 2001, at Seoul National University Children’s Hospital (SNUCH) were included in this study. Isoelectric focusing and enzyme specific PCR were performed to characterize β-lactamase. The presence of qnrA, qnrB, qnrC, qnrS, qepA, and aac(6’)-Ib-cr was determined by PCR, restriction enzyme analyses of PCR products, and DNA sequencing. Minimal inhibitory concentration (MIC) of several quinolones was measured by agar dilution method. Results : The PMQR genes were detected in 9 (21%) of 43 ESCs-resistant E. cloacae isolates. Among them, five isolates were positive for qnrB2, and each two isolates harbored qnrB4 or qnrB5, respectively. qnrA, qnrC, qnrS or qepA was not identified. aac(6’)-Ib was detected in 27 isolates, but aac(6’)-Ib-cr was not found. Among the 9 qnrB-positive isolates, 5 produced SHV-12, 3 were derepressed mutants, and 1 produced pI 7.5 β-lactamase. MIC ranges and percent resistances of nalidixic acid, ofloxacin, levofloxacin, and moxifloxacin for the PMQR genes-positive isolates were higher than PMQR genes-negative isolates. Conclusions : In this study, ESCs-resistant E. cloacae showed a high prevalence of PMQR genes, and qnrB was the only PMQR gene identified.

抗癌丹을 投與한 胃癌 患者 105例에 對한 臨床報告

유화승,최우진,이용연,서상훈,조정효,이연월,손창규,조종관 대전대학교 한방병원 2000 惠和醫學 Vol.9 No.2

Clinical studies were carried out 105 cases of patients with stomach cancer treated by Hangamdan(抗癌丹) from January 1th 1998 to September 30th 2000. The results were summarized as follows; 1. Distribution of those attached by stomach cancer, by sex, showed that Male is more then Female, by age, showed that the number of forties, fifties, sixties are majority. 2. Distribution of diagnostic stage, in descending order; stage Ⅲ(45.1%, top), stage Ⅳ(40.2%). 3. The effects of maintenance and improvement in the symptoms with traditional oriental therapy(77.8%) and combined treatment of western and oriental therapy(92.3%) were observed. The effects of the symptoms were as follows; abdominal pain (16.3%), general body weakness(10.5%), nausea&vomiting (8.6%), diarrhea(6.7%) and etc, in orders. 4. Analysis of hematology attached by stomach cancer, maintenance and increasing of WBC(89.4%), RBC(63.6%), Hgb(62.3%), Platelet(95.6%) were observed. After taken Hangamdan, the safety of the liver and kidney were as follows; maintenance and decreasing of AST(85.3%), ALT(91.6%), BUN(84.8%), Creatinine(92.4%) were observed. 5. Analysis of IL-12 and IFN-γ attached by stomach cancer, increasing of IL-12(39.1%), IFN-γ(69.6%) were observed. 6. Analysis of QOL attached by stomach cancer, maintenance and improvement of combined treatment of western and oriental therapy(91%), traditional oriental therapy(85.2%) were observed. 7. Analysis of survival in patients with Ⅳ stage of stomach cancer, above 6 months(17.1%), 12 months(85.2%) were observed. 8. Analysis of antitumor effects, maintenance of traditional oriental therapy(81.5%) and maintenance and improvement of combined treatment of western and oriental therapy(89.7%) were observed. Analysis of tumor marker attached by stomach cancer, maintenance of CEA(85.7%) were observed. 9. Analysis of curative valuation, maintenance and improvement of traditional oriental therapy(77.7%), combined treatment of western and oriental therapy(82.1%) were observed. From the above results, it is suggested that Hangamdan has significant effects of antitumor and immune activity, also could be usefully applied for stomach cancer patients by combination with western therapy or alone.