• 마이크로전자및패키징학회지
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• 제28권3호
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• pp.25-32
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• 2021

본 논문에서는 X-Band 대역에서 이중 편파 특성을 갖는 Magneto-Electric(ME) dipole 배열안테나를 제안하고, 이를 Low Temperature Co-fired Ceramic (LTCC) 공정을 이용하여 구현 및 측정하였다. 제안된 배열안테나는 LTCC로 구성된 1 × 1 ME dipole 안테나 32 개를 Teflon PCB에 배열하여 8 × 4 배열 안테나로 구성된다. 1 × 1 ME dipole 안테나는 두 쌍의 방사체에서 각각 수직 편파와 수평 편파를 방사하여 이중 편파를 구현하게 된다. 2개의 Port 급전은 LTCC를 이용한 적층 공정을 통해 구현하였으며, 각 각의 Port는 포트 간 격리도를 확보하기 위해 Γ-shaped feeding strip을 통해 독립적으로 방사체에 급전된다. 안테나 배열에 사용된 Teflon PCB는 4층 구조로 형성하였으며, 상단 면과 하단 면을 통해 2개의 Port가 급전된다. 그리고 배열되는 안테나와 Teflon PCB의 임피던스 정합을 위해 Teflon PCB의 전송선로에 λ_g/4 변환기를 적용하였으며 시뮬레이션을 통해 최적 파라미터를 얻었다. 구현된 ME dipole 8 × 4 배열안테나의 크기는 15.5 mm × 11 mm × 4.2 mm이며, Port 1 급전 시 측정된 방사 최대 이득은 18.2 dBi, cross-pol은 1.0 dBi이고 Port 2 급전 시 측정된 방사 최대 이득은 18.1 dBi, Cross-pol은 3.2 dBi로 확인하였다.

• 한국가금학회지
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• 제23권2호
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• pp.85-98
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• 1996

Results of experiments on the nutrient requirements and feeding system of broiler breeder hens were reviewed, and daily requirements of energy and protein were calculated using the prediction equations reported by Scott(1977) and NRC(1981). The experimental reports on daily ME needs of broiler breeder hens were ranged from 400 to 450 kcal, however, the ME needs of caged hens were 92~93% to those of floor-housed hens due to the difference of ME need for activity. The ME needs of broiler breeders decreased with increasing environmental temperature corresponding to a drop of 25 kcal per day for each 5˚C rise. About 80~90% of the daily ME needs were used for body rnaintenance and activity of hens. Experimental results on daily protein needs of broiler breeder hens were ranged from 18 to 22 g, however, calculated protein needs decreased as the BW gain and eggmass output decreased after peak production, and about 60~65% of the daily protein needs were used for egg production. In the current practice, broiler breeder hens are restricted in feed, and consume their daily allowance in the first 2 to 6 h after dawn. The results suggest that eggshell quality can be significantly improved in hens fed during the afternoon when shell calcification is initiated, with no adverse effect on laying rate and fertility of eggs.

• 한국식품영양과학회지
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• 제27권3호
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• pp.537-542
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• 1998

The present study was performed to elucidate desmutagenic principles from Ecklonia stolonifera extracts against 2-amino-1-methyl-6-phenylimidazo[4,5-b] pyridine(PhIP) and 2-amino-3,8-dime-thylimidazo[4,5-f]duinoxaline(MeIQx) with Salmonella/mammalian-microsome mutagenicity test. Alginate, phenols, chlorophyll and carotenoids from Ecklonia stolonifera were extracted and their desmutagenicities were assayed. Alginate hydroysates showed desmutagenic activities against PhIP and MeIQx at high level dose. Phenol fractions and bromophenol showed desmutagenic activity of about MeIQx at high level dose. Phenol fractions and bromophenol showed desmutagenic activity of about 90% per 0.5mg against PhIP and MeIQx. Chlorophyllin among chlorophyll derivatives exhibited remarkable desmutagenic activities of 92.9% and 82.7% at 20uM against PhIP and MeIQx, respectively. Carotenoids, such as lutein and $\alpha$-cryptoxanthin isolated from Ecklonia stolonifera exerted also high desmutagenic activity. Major desmutagenic substances from Ecklonia stolonifera are considered to be chlorophyllin, phenols, lutein, $\alpha$-cryptoxanthin and low molecular alginates.

• Journal of Radiation Protection and Research
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• 제26권3호
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• pp.143-147
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• 2001

The dosimetric properties of Ge- and Er-doped optical fibres are studied. The Ge-doped fibre is found to be more sensitive to radiation and there is little fading of TL signal compared with Er-doped fibre. The Ge- and Er-doped fibres showed a linear response over a range of ${\sim}1\;Gy$ to about 120 Gy and ${\sim}1Gy$ to about 250Gy respectively. The Ge-doped fibre is found to be dose-rate independent both for photons and electron beams of energy ranging from 6 to 10 MeV and 6 to 12 MeV respectively. The fibre is energy independent for energy greater than ${\sim}0.1\;MeV$ for photon or 0.1 MeV for electron beam. From the depth-dose measurement, it was found that the position of maximum dose, dmax, increased with increasing energy ranging from ${\sim}2\;cm$ and ${\sim}2.5\;cm$ for 6 MeV and 10 MeV photons respectively. The central axis percentage depth dose at 10 cm depth was found to be in good agreement with the value obtained using ionization chamber.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 제2회 추계심포지움
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• pp.147-172
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• 1994

Aziridinylbenzoquinones such as 3, 6-diaziridinyl-1, 4-benzoquinone (DZQ) and its 2, 5-methyl analog (MeDZQ) require bioreductive activation in order to elicit their anticancer activities. To determine the involvement of DTD in the activation of these drugs, we have used a ligation-mediated polymerase chain reaction to map the intracellular alkylation sites in a sing1e copy gene at the nucleotide level. We have performed this analysis in two human colon carcinoma cells, one proficient (HT-29) and one deficient (BE) in DT-diaphorase (DTD) activity. In the DTD proficient HT-29 cell line, DZQ and MeDZQ were found to alkylate both 5'-(A/T)G(C)-3' and 5'-(A/T)A-3' sequences. This is consistent with the nucleotide preferences observed when DZQ and MeDZQ are activated by purified DTD to reactive metabolites capable of alkylating DNA in vitro [Lee, C. -S., Hartley, J. A., Berardini, M. D., Butler, J., Siegel., D., Ross, D., & Gibson, N. W. (1992) Biochemistry, 31: 3019-3025]. Surprisingly in the DTD-deficient BE cell line a pattern of alkylation induced by DZQ and MeDZQ similar to that observed in the DTD-proficient HT-29 cells was observed. This suggests that reductive enzymes other than DTD can be involved in activating DZQ and MeDZQ to DNA reactive species in vivo.

• 대한간호학회지
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• 제35권7호
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• pp.1420-1425
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• 2005

Purpose: We try to disclose how much the keywords of the papers from the Journal of the Korean Academy of Nursing coincide with MeSH terminologies and to understand the major subjects of the recent nursing research in Korea from keywords. Methods: Keywords of journals were extracted and compared with MeSH terms. The frequency of the appearance of each keyword was sorted by a descending order. Results: Coincidence rate of 1,235 keywords with MeSH terms was $51.6\%$. Out of them, depression, elderly, stress, self efficacy, quality of life, exercise, middle-aged women, and women appeared most frequently in descending order. Conclusion: Coincidence rate of the keywords with MeSH terms was at an acceptable level, however to improve it, the education of submitters and editorial board members are required, as well as the copy editor, to take a role in checking keywords. To infer the subjects of the research from keywords might well represent the recent topics of research work.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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• pp.149-152
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• 2001

In general, the wireless services based on markup language and provided with wired network requires dedicated gateway system. But in this case, the serious problems such as security vulnerabilities, damage of contents are occurred to the application. In this paper, to improve above problems, we designed and implemented the new application named "Interacted Wired St Wireless Student Information System" using J2ME(Java 2 Micro Edition) platform and XML(eXtensible Markup Language) to transmit user data safely and support the system extendibility maintaining data format consistency respectively.pectively.

• 한국의학물리학회지:의학물리
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• 제20권2호
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• pp.97-105
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• 2009

물 흡수선량표준을 기반으로 하는 선량측정 프로토콜에서는 전자선의 선질결정 지표는 $R_{50}$이며, 선량측정의 정확성을 향상시키기 위하여 전자선의 기준 에너지가 $R_{50}$>7 $g/cm^2$ (E${\gtrsim}$16 MeV)인 고에너지 전자선에서 표준기관에 소급성이 있는 원통형이온함의 물흡수선량교정계수을 이용한 평행평판형이온함의 교차교정을 권고하고 있다. 그러나 이러한 조건을 만족하는 고에너지 전자선은 모든 치료기관에서 보유하기가 어려운 실정이다. 따라서 본 연구에서는 평행평판형이온함의 교차교정 시 16 MeV 이상의 고 에너지 전자선뿐 아니라 12 MeV 이하의 전자선 에너지에서 얻은 평행평판형이온함의 교정계수를 이용하여 선량차이를 각각 비교하였다. 전자선 선량측정은 PTW 30013, Wellhofer FC65G의 Farmer형 원통형이온함과 PTW 34001, Wellhofer PPC40의 Roos형 평행평판형이온함을 이용하였으며 물팬텀내 기준깊이 $Z_{ret}=0.6R_{50}-0.1$(cm)에 원통형이온함과 평행평판형이온함을 같은 위치에 놓고 교차교정을 실시하였다. 교차교정 선질 20 MeV에서 결정된 교정계수를 적용한 물 흡수선량과 전자선에너지 12, 16 MeV에서의 물 흡수선량 차이는 0.2% 이내로 비교적 잘 일치하는 연구결과를 보였다. 그러므로 교차교정 선질 차이에 의한 흡수선량 값 상호 비교한 결과는 측정 불확도내에서 잘 일치하고 있어 각 기관에서 보유하고 있는 의료용가속기의 최고 전자선 선질에서의 교차교정도 유효하다고 사료된다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1999년도 춘계학술대회
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• pp.53-61
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• 1999

Radiation therapy has been used for the cancer treatment and radiation synovectomy$\^$1-3)/. There are two kinds of radiation therapy; the external radiation therapy and the internal radiation therapy. Hitherto, the external radiation therapy has been widely used, but for the lack of its selectivity it requires strong radiation dose and causes the irritation and damage of the normal tissue or organ. Therefore many researchers give their interests to the internal radiation therapy in which the radioactive materials are injected directly into the target organ or tissue. Many ${\beta}$-emitting radionuclides have been studied for the application of the internal radiation theraily. Among them, Holmium-166 has the many beneficial physical characteristics for the internal radiation therapy such as appropriate half life (26.8hr), high ${\beta}$ energy (max. 1.85 MeV(51%), 1.77 MeV (48%), mean 0.67MeV), and low ${\gamma}$ energy (0.081MeV) easily detected by ${\gamma}$-camera. In the internal radiation therapy, the administered radioactive materials should be retained in the target long enough to increase the therapeutic effects and avoid the damage in the normal tissue or organ. For this purpose, radionuclides are used as complex form with carriers. Carriers should have a high affinity with radionuclides in vivo and in vitro, so the complex can be evenly distributed in the lesion but can not be leaked out from the lesion.

• Bulletin of the Korean Chemical Society
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• 제25권9호
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• pp.1346-1350
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• 2004

Pseudo-first order rate constants $(k_{obs})$ are reported for the following solvolyses in approximately isodielectric mixtures: 3- and 4-methoxybenzyl chloride, bromo- and chlorodiphenylmethane, and 4-chloro-, 4,4'-dichloro and 4-methyl-chlorodiphenylmethane in 0-80% v/v nitromethane-methanol mixtures; and bromo- and chlorodiphenylmethane and 4-methyl-chlorodiphenylmethane in various acetonitrile-methanol mixtures (in the range 0-50% v/v) at$25^{\circ}C.$ These data, and literature data for t-butyl halides (Cl, Br, and I), and for p-methoxybenzoyl chloride, show rate maxima in solvent compositions of ca. 30% aprotic cosolvent, explained by a stoichiometric solvent effect on electrophilic solvation. Linear relationships are observed between $(k_{obs})/[MeOH]^2$ and [AP]/[MeOH], where [AP] refers to the molar concentration of aprotic cosolvent. The results are consistent with competing third order contributions to $k_{obs}$, $k_{MM}[MeOH]^2$ with hydrogen-bonded methanol as electrophile, and $k_{MAP}[MeOH][AP]$ with hydrogen-bonding disrupted by the aprotic solvent.