시퀀셜 로테이션 분배기 구조를 이용한 X-band 마이크로스트립 4×4 광대역 원형 편파 배열 안테나

김정한,김중관,김용진,이홍민,Kim, Jung-Han,Kim, Joong-Kwan,Kim, Yong-Jin,Lee, Hong-Min 한국전자파학회 2007 한국전자파학회논문지 Vol.18 No.2

본 논문은 X-band에서 동작하는 마이크로스트립 원형 편파 $4{\times}4$ 배열 안테나의 설계와 제작에 대해 다룬다. 단일 안테나는 정사각형 패치를 사용하고 비대칭 십자 개구 결합 급전 구조를 사용하여 RHCP(Right Handed Crcularly Polarization)로 동작하도록 하였다. 기존의 배열 안테나의 소자간의 간격을 0.8 ${\lambda}_0$에서 0.45 ${\lambda}_0$로 간격을 줄여 실장 면적을 감소시켰다. 급전 선로는 시퀀셜 로테이션 분배기로 $2{\times}2$ 배열 안테나를 설계하여 양호한 이득과 축비 대역폭을 나타내었다 ${\lambda}/4$ Transformer와 T-junction 전력 분배기로 $4{\times}4$ 배열 안테나로 확장하였다. 시뮬레이션으로 확인한 결과 최대 방사 이득은 15.09 dBi로 나타났으며, 축비 대역폭은 3 dB 기준 $9.05{\sim}10.4$ GHz(13.5%)의 양호한 특성을 보였다. 제작된 $4{\times}4$배열 안테나는 10 GHz에서 측정 결과 임피던스 대역폭($VSWR{\leq}2$)은 $8.45{\sim}11.84$ GHz(33.9%)로 나타났으며, 최대방사 이득은 11.10 dBi를 얻었다. 또한 측정된 축비 대역폭은 $9.42{\sim}10.47$ GHz(10.5%)를 얻었다. In this paper, the circularly polarized $4{\times}4$ array antenna is proposed for the X-band. A single antenna consists of square patch and unequal cross-aperture coupled feeding. The RHCP(Right Handed Circularly Polarization) is generated by unequal cross-aperture coupled feeding. By reducing space among elements of way antenna from 0.8 ${\lambda}_0$ to 0.45 ${\lambda}_0$, the mounting area of array antenna is miniaturized. The $2{\times}2$ array antenna is designed using sequential rotation feeding network. The good level of gain, axial ratio, and impedance bandwidth are achieved. The $4{\times}4$ array antenna is extended by ${\lambda}/4$ transformer and T-junction power divider. The simulated maximum radiation gain is 15.09 dBi at 10 GHz. The simulated 3 dB Axial Ratio bandwidth is from 9.05 to 10.4 GHz(13.5%). Also the measured impedance bandwidth($VSWR{\leq}2$) of manufactured $4{\times}4$ array antenna is from 8.45 to 11.84 GHz(33.9%). The measured maximum radiation gain is 11.10 dBi at 10 GHz. The measured 3 dB Axial Ratio bandwidth is from 9.42 to 10.47 GHz(10.5%).

한국인 사체에서의 정상 종골의 실측: 예비보고

김정한,곽희철,김전교,정양환,Kim, Jung-Han,Gwak, Heui-Chul,Kim, Jeon-Gyo,Jung, Yang Hwan 대한족부족관절학회 2014 대한족부족관절학회지 Vol.18 No.1

Purpose: The purpose of this report is to evaluate the measured values of normal Korean calcaneus by conduct of a cadaveric study. Materials and Methods: A total of 42 calcanei were obtained from Korean cadavers. A digital goniometer was used for measurement of B$\ddot{o}$hler's angle, Gissane angle, posterior facet articular inclination angle, and Fowler-Philip angle of calcaneus. A vernier caliper was used for measurement of the maximal antero-posterior length, maximal transverse width, and maximal height of calcaneus. Results: The average B$\ddot{o}$hler's angle, Gissane angle, posterior facet articular inclination angle, and Fowler-Philip angle was $32.3^{\circ}{\pm}5.0^{\circ}$, $114.4^{\circ}{\pm}8.2^{\circ}$, $61.2^{\circ}{\pm}4.4^{\circ}$, and $60.3^{\circ}{\pm}7.6^{\circ}$. The average maximal antero-posterior length, maximal transverse width, and maximal height of calcaneus was $74.2{\pm}3.0mm$, $43.0{\pm}4.0mm$, and $42.5{\pm}3.0mm$. Conclusion: The measured values of normal Korean calcaneus were lower than the values reported in the international literature. Therefore, development of appropriate instruments reflecting the anatomical characteristics of Koreans will be needed.

족근골 유합의 발생 빈도: 단일 기관 자기공명영상 분석

김정한,곽희철,이창락,김영준,김전교,이선주,이정한,박준호,Kim, Jung-Han,Gwak, Heui-Chul,Lee, Chang-Rak,Kim, Young-Jun,Kim, Jeon-Gyo,Lee, Sun-Joo,Lee, Jeong-Han,Park, Jun-Ho 대한족부족관절학회 2016 대한족부족관절학회지 Vol.20 No.3

Purpose: Tarsal coalition results from defects during the developmental stage and produes ankle pain and limitations in the range of motions. Its incidence has been reported to be 1%, but there has not been any reports with respect to Koreans. Therefore, we evaluated the prevalence of tarsal coalition in Koreans. Materials and Methods: Between 2005 and 2014, we analyzed a total of 733 cases of foot and ankle magnetic resonance imaging (MRI) in our hospital. There were 391 men and 342 women. All MRI readings were read by a radiologist in our hospital. We classified the coalitions in accordance with the histological and anatomical characteristics, and calculated the prevalence in each group. Moreover, we tried to determine the prevalence of tarsal coalitions in accordance with sex, age, and proportion of the symptomatic tarsal coalitions. Results: There were a total of 11 MRIs of tarsal coalition - 9 talocalcaneal coalitions, 1 calcaneocuboidal coalition, and 1 calcaneonavicular coalition. Nine tarsal coalitions were observed in men and 2 in women. Conclusion: Through this study, we found that the prevalence of tarsal coalition, including the asymptomatic patients, is similar to the previously known prevalence (1%). By getting more MRIs of the foot and ankle, we could better represent the prevalence of tarsal coalitions in Koreans.

Isoguanosine과 Berberine 1 : 1 혼합물의 항암효과

김정한,이상준,한영복,문정조,김종배,Kim, Jung-Han,Lee, Sang-Jun,Han, Young-Bok,Moon, Jung-Jo,Kim, Jong-Bae 대한약학회 1994 약학회지 Vol.38 No.2

Isoguanosine and berberine 1:1 mixture[l:[1(mole:mole)] has been prepared and evaluated by measuring antitumor effects against various tumor cell lines in culture and in mice. We reported that the synergistic effect of isoguanosine and berberine mixture has been revealed compared with each of isoguanosine and berberine increased by $3{\sim}8$ times than that of each components in various tumor cell lines in vitro. The most effective dose of isoguanosine and berberine mixture was 60 mg/kg/day in mice bearing S-180 solid tumor, the %(1-T/C) values were 70%. Against the P-388 leukemia, isoguanosine-berberine mixture was the most effective at the dose of 60 mg/kg/day, the %T/C values were 163%.

원위 경골 골절에서 금속정 및 금속판 고정술의 결과 비교

김정한,곽희철,이창락,정양환,Kim, Jung-Han,Gwak, Heui-Chul,Lee, Chang-Rack,Jung, Yang-Hwan 대한족부족관절학회 2015 대한족부족관절학회지 Vol.1 No.2

Purpose: We analyzed and compared the clinical and radiologic results between minimally invasive plate osteosynthesis and internal fixation using intramedullary (IM) nail in the treatment of distal tibia fractures. Materials and Methods: From March 2005 to June 2013, 65 cases of distal tibia fractures treated with either plate fixation or IM nail fixation were analyzed retrospectively by clinical and radiologic evaluations. The clinical results were compared using the American Orthopaedic Foot and Ankle Society (AOFAS) score, Olerud-Molander ankle score (OMAS), and visual analogue scale (VAS) score at the last follow-up. The radiologic results were compared by time to bone union, complications such as nonunion, delayed union, and malunion. Results: The clinical results (according to OMAS, AOFAS score, and VAS score) were 77.47, 84.76, and 1.75, respectively, in the plating group, and 90.21, 91.00, and 1.25, respectively, in the nailing group, and there was no statistically significant difference. Plating group showed earlier union than the nailing group and the nailing group showed higher frequency of non-union and delayed union than plating group. Conclusion: In treatment of distal tibia fractures, two methods showed appropriate results. Therefore, thorough investigation of the types of fracture, state of soft tissues, and advantages and disadvantages of the two methods should be conducted in the treatment of distal tibia fractures.

1-페닐술포닐 부탄-2-온의 빵효모 환원 : 손쉬운 (S)-(+)-3-옥탄올의 합성

김정한,오원택,임정훈,Jung-Han Kim,Won-Taek Oh,Jeong-Hoon Lim 대한화학회 1991 대한화학회지 Vol.35 No.5

미세유두상 갑상선암

김정한,양정현,Jeong Han Kim,Jung-Hyun Yang 대한갑상선-내분비외과학회 2002 The Koreran journal of Endocrine Surgery Vol.2 No.1

Purpose: Papillary microcarcinoma of the thyroid gland is defined as a tumor of 1.0 cm or less in diameter according to the WHO. Long-term follow-up of patients with papillary tumors of small size has shown that the prognosis is very good in spite of their ability to metastasize to regional lymph node and distant site, but the surgical management of them are still unclear. The aim of this study is to analyze the clinical and pathologic features and to determine the adequate extent of surgery of papillary microcarcinomas. Methods: 189 patients with papillary carcinoma of 1 cm or less in diameter underwent thyroidectomy at center between 1994 to 2001. Their medical records were reviewed retrospectively. Chi-square test was used for statistical analysis. Results: 26.3% of 720 papillary carcinomas were microcarcinomas and 44.4% of patients with these tumors were presented for palpable neck mass. 73.6% of 189cases were diagnosed preoperatively as papillary carcinoma by FNAC and their mean size was 6.1 mm. Only 22 patients underwent lobectomy and the others did subtotal or total thyroidectomy with/without modified radical neck dissection. Among 5 recurred cases, 3 recurred in contralateral lobe after lobectomy and 2 in cervical lymph node after subtotal or total thyroidectomy. Smaller tumors had a lower rate of extra- thyroidal extension but the same rate of lymph node metastasis as larger tumors. Conclusion: Detection by screening ultrasonography and the proportion of microcarcinoma in papillary carcinoma are increasing and more than subtotal thyroidectomy is recommended for papillary microcarcinoma due to its multifocality and remnant recurrence. (Korean J Endocrine Surg 2002; 2:31-36)

두 개의 기생 패치를 갖는 고 이득.광대역 SAP 안테나

김정한,김용진,이홍민,Kim, Jung-Han,Kim, Yong-Jin,Lee, Hong-Min 한국전자파학회 2007 한국전자파학회논문지 Vol.18 No.8

본 논문에서는 SDMB(Satellite Digital Multimedia Broadcasting) 시스템에서 동작하는 고 이득 광대역 안테나를 구현하였다. 제안된 안테나는 표면파를 억제하기 위한 SAP(Shorted Annular Patch) 구조와 이득, 대역폭 그리고 지향성을 개선시키기 위하여 $0.25 {\lambda}_0$ 간격을 갖는 3차원 배열의 기생 SAP로 구성되었다. 원형 패치상의 서로 반대 방향으로 농인 두 개의 슬릿을 이용하여 RHCP(Right Hand Circular Polarization)로 동작하도록 하였다. 모의 실험 결과, 제안된 안테나의 최대 방사 이득은 기존의 마이크로스트립 패치 안테나에 비해서 5.22 dBi 개선된 12.6 dBi로 나타났다. 제작된 안테나는 동작 주파수 2.63 GHz에서 최대 방사 이득이 10.5 dBi로 나타났다. 측정된 임피던스 대역폭$(VSWR{\leq}2)$은 기존의 마이크로스트림 패치 안테나에 비해서 300 MHZ 개선된 $360 MHz(2.488{\sim}2.848 GHz)$이며, HPBW(Half Power Beam Width)는 $45.8^{\circ}$, FBR(Front Back Ratio)은 15.49dBi로 나타났다. 3dB 축비 대역폭은 220 MHz$(2.54{\sim}2.76 GHz)$를 얻었다. In this paper, the high gain and broadband antenna operating for SDMB(Satellite Digital Multimedia Broadcasting) system is realized, The proposed antenna consists of the SAP(Shorted Annular Patch) structure, which inhibits surface-wave and the parasitic SAP element with spacing of $0.25 {\lambda}_0$ in order to improve gain, bandwidth and directivity. The RHCP(Right Hand Circular Polarization) is generated by two slits, which are made along the periphery of the circular patch at the diametrically opposite points, The simulated maximum gain of the proposed antenna is 12.6 dBi, which is better 5.22 dBi than maximum gain of the conventional microstrip patch antenna. The measured maximum gain is 10.5dBi at operating frequency 2.63GHz. Also, the measured impedance bandwidth$(VSWR{\leq}2)$ of the proposed antenna is $360MHz(2.488{\sim}2.848 GHz)$, which is better 300 MHz than the bandwidth of the conventional microstrip patch antenna. The measured HPBW(Half Power Beam Width) of the proposed antenna is $45.8^{\circ}$, and the measured FBR(Front to Back Ratio) is 15.49 dBi, The 3dB axial ratio bandwidth is 220 MHz$(2.54{\sim}2.76 GHz)$.

포스터 발표 - 무기재료분과 / 전기화학분과 / 촉매분과 : Ba - Cu 와 Mn - Zr 산화물의 NOx 제거 특성 연구

김정한,배정훈,손종락,박상언 ( Jung Han Kim,Jung Hoon Bae,Jong Rack Sohn,Sang Eon Park ) 한국공업화학회 1997 한국공업화학회 연구논문 초록집 Vol.1990 No.3

소독제가 개인용 트레이와 실리콘 인상재의 접착력에 미치는 영향에 대한 연구

김정한,정창모,전영찬,황의성,Kim, Jung-Han,Jeong, Chang-Mo,Jeon, Young-Chan,Hwang, Hic-Seong 대한치과보철학회 1996 대한치과보철학회지 Vol.34 No.2

The effects of impression tray disinfection procedures on the bond strength of impression-material adhesive to two of types resin trays were evaluated with a tensile test. Autopolyme-rizing acrylic resin was formed into 1x1x1 cm cubes. A hook was attached to each cube with autopolymerizing acrylic resin. Perforated trays were fabricated with stops to maintain an even 3 cm of impression material over the resin block. Hook on the opposite side of the perforated tray permitted attachment of the metal plate to a mechanical testing machine. Before adhesive was applied, one third of the resin specimens were immersed in a 5% sodium hypochlorite solution : one third in a 2% glutaradehyde solution, and one third were kept in the "as fabricated" condition. Three products(Perfect ups, Exafine, and Exp-ress) of polyvynil siloxane impression material-adhesive system were evaluated. The resin-impression material-metal plate couples were attached to a mechanical testing machine and tensile forces were applied at a separation rate of 10 centimeters per second. The results were as follows; 1. Both disinfectant and adhesive had effects on bond strength values, but adhesive had more effect than disinfectant(p<0.01). However, there was no interaction between dinin-fectant and adhesive(p>0.01). 2. Mean bond strength values for the Perfect materials were about 85% less than that of the Exafine or the Express materials. However, there was no stastically significant difference between the mean bond strength values of the Exafine materials and the Express materials(p>0.05). 3. The use of disinfectants produced significant reduction in bond strength values(p<0.05). But there was no stastically significant difference between the mean bond strength values of the groups treated with disinfectants(p>0.05).