Lightweight Printed Dipole Antenna Array With 3×2 Beamforming Network for Wide UAV Communication Coverage

Dong‑Geun Seo,Jeong‑Soo Park,Gun ‑Ki Lee,Wang‑Sang Lee 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.4

In this paper, a lightweight printed dipole antenna array with 3×2 beamforming network for wide unmanned aerial vehicle (UAV) communication coverage is presented. The proposed antenna consists of an upper substrate, a lower substrate, and two supports with a microstrip feeding. The upper substrate has a two-element printed dipole antenna array, and the lower substrate includes a beamforming feeding circuit and a ground plane as a refector of the proposed antenna array for gain improvement. For wide beam coverage, the proposed feeding network consists of three RF switches, one Wilkinson power divider, and one 90° hybrid coupler, and generates the wide beam using one broadside beam and two end-fre beams. Measured impedance bandwidth, peak gain, and half-power beamwidth (HPBW) of the proposed array operated from 5.03 to 5.15 GHz are approximately 2 GHz, 4.3 dBi, and 155°, respectively.

Two New Species of Placolecis (Lichenized Ascomycota) from China

( An Cheng Yin ),( Xin Yu Wang ),( Dong Liu ),( Yan Yun Zhang ),( Mei Xia Yang ),( Li Juan Li ),( Li Song Wang ) 한국균학회 2019 Mycobiology Vol.47 No.4

Two new species of the lichen genus Placolecis are discovered in China, namely P. kunmingensis An. C. Yin & Li S. Wang and P. sublaevis An. C. Yin & Li S. Wang. The new combination P. loekoesiana (S.Y. Kondr., Farkas, J.J. Woo & Hur) An. C. Yin is proposed. Placolecis kunmingensis is characterized by having simple, spherical or ellipsoid, hyaline spores, and pear-shaped pycnidia; while P. sublaevis can be distinguished by its thallus forming larger aggregations with slightly flattened lobes at the thallus margin, and urn-shaped pycnidia. Descriptions, a phylogenetic tree and a key are provided for all the known Placolecis species in China.

개에서 발생한 이버멕틴 중독증 1례

여동원,윤기영,박정호,이왕희,송근호,박성준 忠南大學校 獸醫科大學 附設 動物醫科學硏究所 2011 動物醫科學硏究誌 Vol.18 No.1

A 1-year old, intact male Jin-do dog with ataxia, hypersalivation and anorexia was referred to the Veterinary Medical Teaching Hospital of Chungnam National University. Ivermectin toxicosis was diagnosed by the history taking, clinical signs, physical examination and neurological examination. After therapy with intravenous fluid and lipid emulsion administration, the clinical signs were found to have significantly improved.

흰쥐에서 염화비닐 폭로수준에 따른 소변내 thiodiglycolic acid 농도의 변화

왕승준,차봉석,노재훈,신동천,김명수,전근재 大韓産業醫學會 1999 대한직업환경의학회지 Vol.11 No.4

Objectives : It is the objective of this research to identify the variation of thiodiglycolic acid(TdGA) in urine with vinyl chloride monamer(VCM) exposure levels through methylation. Methods : After rats were exposed to vinyl chloride monomer of 4 levels, 0㎎/㎥, 50㎎/㎥, 150㎎/㎥, 500㎎/㎥, respectively, of which urine was sampled in each sampling time of 0 hour, 2 hours, 4 hours, 8 hours, 16 hours, 36 hours, 48 hours. After urine had been methylated with diazomethane in the preliminary experiment and the peak of 146 m/z had been verified, the main experiment was done. Results : In the variation of TdGA with sampling times, concentration of TdGA increased rapidly in 4 hours and then decreased after 8 hours. When the variation of urinary TdGA concentration in urine according to exposure level of VGM was verified through Kruskal-Wallis statistical method at each sampling time, the significant increment with the exposure levels at 2 hours, 4 hours, 8 hours after exposure was clarified. Conclusion : TdGA concentration in urine with increment of VCM exposure level increased, especially significantly at 2 hours, 4 hours, 8 hours of sampling time.

운동장을 이용한 우수의 포집, 수량 및 수질에 관한 연구

왕창근,이영복,이동곤 忠南大學校 環境問題硏究所 2003 環境硏究 Vol.21 No.-

In this study, quantity and quality of rainwater collected by soil and sand as the playground collection materials were investigated and CNURCPM (Chungnam National University Rainwater Collection Prediction Model) was developed to predict amount of collected rainwater. Quantity of collected rainwater in soil and sand (depth 5 cm) collection system was 615 L(63%) and 7,315 L(77%) for study period, respectively. Average turbidity of collected rainwater in soil and sand collection system was 9.70 NTU, 2.05 NTU for study period, respectively. In case of heavy metal, the concentrations of Fe and A1 were higher than the other heavy metals in both soil and the sand. But in this analyzing the Fe and A1 were less than the standard of water quality that was required in drinking water. So the collected water was insignificant because concentration of heavy metal was not serious. List of water quality; pH, TOC, COD_(Mn), NH_(4)-N, NO_(3)-N were lower or a little higher than the standard of water quality and the item of coli-form was higher than the standard of water quality. These result suggest that the water needs the second treatment such as disinfection. To predict amount of collected rainwater, CNURCPM was developed. For sand collection material, predicted amount by CNURCPM and actual collected amount were 7,534 L and 7,315 L, which were very closed.

생쥐 말초에서 성숙 T세포의 증식

이동섭,이왕재 대한해부학회 1999 Anatomy & Cell Biology Vol.32 No.5

펩티드가 제한된 상황에서 transgenic CD4T세포의 발달

이동섭,이왕재 대한해부학회 1999 Anatomy & Cell Biology Vol.32 No.5

血府逐瘀湯과 그 構成藥物群이 Alloxan 糖尿 白鼠의 血淸 組成 및 抗酸化 效果에 미치는 影響

朴宣東,朱旺錫,高元道 대한본초학회 2002 大韓本草學會誌 Vol.17 No.1

This study was reseached to investigate the effect of Hyulbuchukeotant(?????) and its component groups on diabetes, free radical and antioxidative defense system in alloxan-induced diabetic rats, The experimental group was divided into three groups: Hyulbuchukeotang (HCT), and its components groups, Sayeoksan(H-sa) and Dohong- samultant(H-do). The results were obtained as follows: In the study of effect on diabetes, the level of glucose was considerablely reduced by HCT, H-sa and H-do with high significancy. In the change of fat metabolism, all experimental groups significantly changed the level of triglyceride, total cholesterol and HDL cholesterol expecially HCT and H-do group, but H-sa group has less significancy. In the change of protein metabolism, all experimental groups changed the level of total protein and albumin with high significancy. In the change of kidney function, HCT decreased the level of creatinine and BUN with high significancy, H-sa and H-do did with some significancy too. In the study on free radical scavenging effect in vitro, it has shown that all experimental groups have significant suppressing effect on peroxidation of linoleic acid on concentration, and in the scavenging effect of DPPH radical, inhibitory effect of superoxide in xanthine-xanthine oxidase system and inhibitory effect on lipid peroxidation reaction by hydroxy radical in H₂O₂-Fe^2+ system, all experimental groups have some activity. In the study on antioxidative defense system in vivo, HCT reduced the amount of lipid peroxide in serum and liver with high significantcy, and H-sa, H-do group did too with some significancy. In hepatic catalase activity, all experimental groups had showed activity on catalase, but H-sa no significancy. In the level of hepatic hlutathione, HCT increased the amount of glutathione significantly, but other groups with no significancy. In the activity of glutathione-s-transferase, all experimental groups has decreasing effect with significancy. These results suggest that Hyulbuchukeotant(?????) has strong effect on diabetes and peroxidative damage by free radical, so it is useful to prevent diabetes.

한국형 출혈열 병원체 한탄바이러스의 조직배양 세포에서의 증식

박동욱,이호왕 고려대학교 의과대학 1982 고려대 의대 잡지 Vol.19 No.3

Korean hemorrhagic fever (KHF) was recognized for the first time in 1951 among United Nations troops and has remained endemic near the demilitarized zone between North and South Korea. But, recently it appears to have spreaded all over the World. In 1976 Lee & Lee succeeded in demonstrating an antigen in the lungs of the striped field mouse, Apodemus agrarius, which gave specifie immunofluorescent antibody reactions with sera from patients convalescent from KHF for the first time. In 1981 Lee et al. registered this antigen as Hantaan virus. Recently, French et al. reported a successful growth of the virus in A549 cells. This is the successful results on growth curve after inoculation of Hantaan virus into A549 cells which originated from alveoler epithelial cells of human lung cancer. The results are summerized as follows. 1. The propagation of Hantaan virus could be demonstrated in the cytoplasm of A549 cells on 3rd day after inoculation of the virus, about 60% of cells were infected on 5th day, 80% on 6th day and 100% on 8th day. Cytopathic effect was not appeared. 2. The viral antigens were appeared as a fine spots in the cytoplasm of cells by indirect immunofluorescent antibody technique and at times as a granule-like morphology. 3. The infected A549 cells with Hantaan virus can be used as an antigen for serologic diagnosis of KHF and there was no occurence of nonspecific reaction.

단일전자 다중접합 트랩의 대전에너지와 문턱전압

문성왕,강동식,강영봉 濟州大學校 師範大學 科學敎育硏究所 1999 科學敎育 Vol.16 No.-

Based on the analytic solution to the electrostatic problem of the multi-junction trap with equal N-junction capacitances C and a well capacitance Cw, we obtain explicit expressions for the charging energy, the GiMs free energy, the energy barrier height and the threshold voltage. In particular, when an electron is already trapped in the store island, we analyze the effect of the well capacitance and the number of junction for single electron multi-junction txap. In the C_(w)/C>3/Ncase, an electron can be trapped in the store island height depernds on the number of junction, the value of barrier height is Ne^(2)/8C for C_(w)/C>1. Thus, when N is large and C_(w)/C is large, it is favor of trapping electron in the store island. We find that multi-junction trap with small well capacitance is not suitable for studying the single electron trap. The threshold voltage is proportioned to the bias voltage U and the number of junction N