• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2001.11a
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• pp.343-343
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• 2001

최근 전자산업과 전파통신산업의 발달에 따라 불요전자파에 의한 전자파장해가 심각한 수 준에 이르게 되었다. 그 결과 국 . 내외 전자파환경은 나날이 악화되고 있으며, 이로 인한 사 회적 문제가 점차 증가되고 있는 실정이다. 이에 대한 대책으로 CISPR(Comite Internationale S Special des Perturbations Radioelectrique), FCC (Federal Communications Commissions) A ANSI(Amercian National Standards Institute) 둥이 주축이 되어 국제 규정이 제정되어 각종 전자기기들에 대해 방사(EMI) 및 내성(EMS)의 규제가 강화되고 있다. 그러나 국제규정이 요구하는(30 MHz - 18 GHz) 주파수 범위에서의 EMIjEMS 측정을 하기 위해 광대역(Broad-band) 전파무향실(Anechoic Chamber)이 필요하지만1 기존의 Ferrite T Tile 또는 그리드형 전파홉수체는 20 dB 이상 전파를 홉수할 수 잇는 주파수 대역이 30 M MHz - 400 MHz 또는 780 MHz에 불과하기 때문에 상기의 조건을 만족하는 전파무향실 을 구성하기에는 곤란한 실정이다. 본 논문에서는 국제 규격을 만족하는 전파무향실을 위한 광대역 전파홉수체를 개발하기 위해, 다충형으로 구성하고, 전파흡수체의 형상을 변화시켜 등가재료정수법을 사용하여 설계하고 그 특성을 평가함을 그 목적으로 하였다. 따라서 본 논문에서는 본 연구실에서 기폰에 제안한바 있는, 금속판 위에 타일형 페라이 트 충, 그 위에 원추절단형 페라이트 층과 원통형 페라이트 층을 적층시칸 형상의 전파홉수 체는 30 MHz - 6 GHz 정도까지 커버할 수 있으나, 1 GHz 부근의 주파수 대에서 16 dB 정도의 홉수능 밖에 가지지 못하였다. 이를 개선하기 위해, 금속판 위에 타일형 페라이트 층 을 형성하고 그 위에 원통형 페라이트 충, 원추절단형 페라이트 충I 원통형 페라이트 충, 타 원형 페라이트 충을 형성한 새로운 형태의 전파홉수체를 제안하였다. 본 논문에 제안한 새로운 형태의 전파흡수체의 시물레이션 결과 30 MHz - 20 GHz의 주파수 범위에서 전반적으로 25 dB이상의 전파흡수능을 가짐을 확인하였으며/ 특히 기폰에 제안한 전파홉수체와 비교하면,1GHz 부끈에서의 전파홉수능을 10 dB 이상 개선하였다. 나아가서/ 실재로 제작한 전파흡수체의 측정된 주파수특성이 시율레이션에 의한 이론치와 3 30 MHz - 6 GHz의 범위에서 잘 일치함을 확인하였다. 또한y 전파 홉수체의 전체 높이는 2 27 mm 밖에 되지 않으므로 본 연구에서 제안한 전파 홉수체를 사용할 경우 전파무향실의 유 효공간 확보에 매우 유리한 이점을 가진다

• Journal of Aquaculture
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• v.4 no.1
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• pp.67-71
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• 1991

Sensitivity to ethylmethanesulphonate(EMS) on Ulva Pertusa Kjellman thalli was investigated as preliminary studies aimed at mutation breeding of seaweeds. When the thalli were grown in medium containing the mutagen no growth and about $20{\%}$ growth inhibition occurred at $0.05{\%}$ and $0.025{\%}$ EMS-mixed medium respectively. In the case the thalli were treated short time at high concentration mutagen solution followed by culture in control medium no growth and about $10{\%}$ growth inhibition occurred at 40 min. in $1.0{\%}$ and 80 min. in $0.5{\%}$ EMS solution respectively. Among the mutagenized tissues, some showed variation in growth from and cell color contrast to the mother tissue. The mutagenized tissue polypeptide pattern using sodium dodecyl sulphate-polyacrylamide gel electrophoresis was simiiar that of the mother tissue except about 6.6 kD polypeptides.

• Investigative Magnetic Resonance Imaging
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• v.24 no.3
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• pp.95-122
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• 2020

In this article, we evaluated the performance of radiofrequency (RF) coils in terms of the signal-to-noise ratio (S/N) and homogeneity of magnetic resonance images when used for ultrahigh-frequency (UHF) 7T magnetic resonance imaging (MRI). High-quality MRI can be obtained when these two basic requirements are met. However, because of the dielectric effect, 7T magnetic resonance imaging still produces essentially a non-uniform magnetic flux (|B₁|) density distribution. In general, heterogeneous and homogeneous RF coils may be designed using electromagnetic (EM) modeling. Heterogeneous coils, which are surface coils, are used in consideration of scalability in the |B₁| region with a high S/N as multichannel loop coils rather than selecting a single loop. Loop coils are considered state of the art for their simplicity yet effective |B₁|-field distribution and intensity. In addition, combining multiple loop coils allows phase arrays (PA). PA coils have gained great interest for use in receiving signals because of parallel imaging (PI) techniques, such as sensitivity encoding (SENSE) and generalized autocalibrating partial parallel acquisition (GRAPPA), which drastically reduce the acquisition time. With the introduction of a parallel transmit coil (pTx) system, a form of transceiver loop arrays has also been proposed. In this article, we discussed the applications and proposed designs of loop coils. RF homogeneous coils for volume imaging include Alderman-Grant resonators, birdcage coils, saddle coils, traveling wave coils, transmission line arrays, composite right-/left-handed arrays, and fusion coils. In this article, we also discussed the basic operation, design, and applications of these coils.

• KSBB Journal
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• v.19 no.3
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• pp.169-173
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• 2004

The Rhodiola Sachalinensis 5 g were mixed and extracted with methanol 150 $m\ell$ at the room temperature for 12 h. The effluents were collected and grouped into the two. Un this experimental condition, the mobile phase composition were linearly changed as follows; water/methanol : 90/10 - 30/70 (vol. %, for 5 min), 30/70 - 10/90 (vol. %, for 15 min) and an analytical column (3.9 ${\times}$ 25 em, 15 $\mu\textrm{m}$ particle size, and 300 ${\AA}$ pore size) was utilized. The performance of the extracted Rhodiola Sachalinensis as a whitening agent was not favorable, so it classifies the Rhodiola Sachalinensis extractions with two fractions and collects each fraction for whitening agent assay. For the in-vivo melanin production ratio assay that used melanin-a cell in 10 ppm concentration, it was 58.6%, the first fraction of the effluents collected between 1.0 and 4.0 min, while it was 60％ between 10.4 and 17.6 min for the second fraction, which were more efficient than that of arbutin, 45.6%.

• Health Policy and Management
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• v.8 no.1
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• pp.232-265
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• 1998

Taiwan has experienced rapid economic growth during the past two decades. As a result, the demand for health care in Taiwan has increased rapidly. To meet the rising demand, Taiwan implemented a National Health Insurance (NHI) program on March 1, 1995. This program now covers more than 96 percent of Taiwan's citizens. Implementation of the NHI in 1995 represents fulfillment of a primary social and health policy goals of Taiwan. The goals of the NHI program is to eliminate financial barriers of health care for the citizens, to improve the quality of care. To achieve these goals, the NHI was designed on the following principles: 1. All Taiwan citizens are compul내교 joined the NHI program by law; 2. The NHI program provides comprehensive services; 3. The NHI is run by one single govt' subsidy; 5. The NHI adopt fee-for-services scheme to pay medical expenses and copayment to avoid abouse of medical services. However, the scheme did not bring in the efficient use of health care C. National Health Council, 1986 NARC, Aging in Japan, International Publication Series 1991;2 Kahana EF. Kiyak HA. Attitude and behavior of staff in facilities for the aged, 1984 Naoki I, John CC. Health polic report japan's medical care system, New England Joumal of Medicine 1995; 333(19) National Economic Research Associates, The Health CAre System in Japan, NERA, 1993. National Federation of health Insurance Societies (KEMPOREM), Health Insurance and Health Insurance Societies in Japan, 1995. Owe Ahlund, Aging and housing in sweden, Paper presented at the International Symposium, Long term Care Facility, 1993. Statisitics Jahrbuch, Statistisches Bundesamt, 1992. Stein S. Linn, MIW. and Stein EM. Patient's anticipation of stress in nursing home care, 1985. U. S. Senate Special Committee on Aging, A Report of the special Committee on Aging, Washing D. C, 1992. U.S. Bureau of the Census, 1994.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.3
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• pp.209-213
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• 1991

Early maturing hybrids(Comet 80, Comet 85 and Linda) and mid-late maturing hybrid (Suwon 19) were grown at Suwon to study the influence of maturity, plant population, and sowing date (45, 55, and 65 days delayed from the recommended sowing date of Suwon 19) on the dry matter yields, percentage ears and TDN yields. Com was planted at the density of 60 x 20, 50 x 20 and 40 x 20 em. Dry matter yields were not significantly different between the early and mid-late maturing hybrids in the delayed sowing time, but significantly higher in 20 x 50cm of planting density in early maturing hybrids. As sowing was delayed to Jun. 22 ear content decreased from 40.3% (early maturing hybrid) to 6.7% (Suwon 19). This resulted in significantly 24.1% higher TDN yield in Comet 85 than in Suwon 19.

• Journal of Chest Surgery
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• v.32 no.12
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• pp.1078-1086
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• 1999

배경 :폐포내 fibronectin(FN)의 분포와 역할은 많은 연구자에 의하여 연구되어왔다. 흰주에서 폐의 분화시 FN은 태자에서 폐포의 기저막에 주로 분포되고 간엽조직에서도 관찰되면 분화가 진행되면 폐포막의 간질조직에 FN의 함량이 높아진다. 또 FN은 일반적으로 폐포대식세포(alveolar macrophage)에서 분비되고 폐에 질병이 발생하였을 때 다량의 FN이 폐포대식세포에서 분비된다고 보고되어 있다(Schoenberger 등 1984: Ozaki 등 1990; Rom 등 1987 ; Cordier 등 1990) 저자는 흰쥐의 폐포발생이 진행중인 폐포기 후반에서의 폐포막내 정상적인 FN이니 분포의 변화와폐포를 구성하는 큰 폐포세포(type II pneumocyte)에서의 FN의 분비여부를 면역조직염색법과 전자현미경을 이용하여 추적하고자하였다 실험대상 및 방법: 청정동물실에서 사육한 SPF 흰쥐(Sprague-Dawley 계)를 임신시켜 질도말법을 이용하여 태령을 정한 뒤 태아제 17일 및 20일 출생 제 1일, 2일, 3일, 5일, 및 7일의 신생흰쥐를 실험동물로 사용하였으며 대조군의 흰쥐는 체중 200ㅎ의 건강한 수컷을 사용하였다 흰쥐의 폐조직은 면역조직염색을 위해 rabbit anti rat fibronectin polyclonal antibody를 일차항체로 biotinylated goat anti rabbit IgG를 이차항체로 사용하여 폐실질세포내 FN의 분포를 LM으로 관찰하였고 한편 폐포막을 구성하는 세포 중 큰폐포세포가 FN을 분비하는 세포인지를 추적하기 위해 금과립을 첨가한 항체를 사용하여 큰 폐포세포내 FN의 분포를 EM을 이용해서 추적한 결과 다음과 같은 결과를 얻었다 결과 : 제 17일 및 20일 태아시기의 폐에서의 혈관주위에 강한 FN반응이 관찰되었다 출생후 폐포막의 FN의 활성은 출생후 5일 및 7일에 최고주에 달했다. 출생직후 1-2일경에 혈관의 조직내 FN의 활성이 양성을 나타내지만 3일이후 활성이감소되었다. 폐포대식세포내 FN의 활성은 출생후 증가되었다. 폐조직내 소기관지의 FN의 활성은 출생후 완만하게 상승되었다. 큰 폐포세포는 출생 1-3일에 일정량의 FN 반응이 세포질과 미세융모내에 관찰되었다. 결론 : 이상과 같은 결과로 흰쥐의 폐포의 분화과정이 계속되는 출생후 폐에서 FN의 분비는 7일이내에 성숙흰쥐의 폐포내 반응과 비슷한 반응으르 보이며 이때 폐의 실질조직은 분화가 거의 완료되었을 것으로 사료되었고 큰 폐포세포에서도 FN이 분비되는 것으로 결론지울수 있다.

• The Journal of Korean Obstetrics and Gynecology
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• v.33 no.1
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• pp.1-18
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• 2020

Objectives: This review is aimed at assessing the efficacy and effectiveness of oriental medicine for the prevention of Ovarian Hyperstimulation Syndrome (OHSS) through literature research and overview. Methods: Database searching was conducted to identify relevant randomized controlled trials (RCTs) on oriental medicine for the prevention of Ovarian Hyperstimulation Syndrome. Studies were searched from Journal of Korean Obstetrics and Gynecology, Korean studies Information Service System, Korean Medical Database, China National Knowledge Infrastructure, Cochrane library, PubMed and EmBase up to 7^th November, 2019. Results: Ten RCTs were finally selected. Eight studies intervened with oral Chinese herb medicine, one is intervened with Chinese medicine enema and the other with acupuncture. Eight studies concluded that intervention with oriental medicine significantly decreased OHSS incidence. Five studies showed significantly higher pregnancy rate in the intervention groups. Two studies reported higher ovulation rate and other two studies showed more maturated eggs than the control groups. Four studies showed opposite results in serum Estradiol level. Vascular Endothelial Growth Factor level was significantly lower in the intervention groups in two studies. Conclusions: From ten studies, oriental medicine reduced OHSS incidence rate and showed preventable effectiveness. Further strictly designed studies and acupuncture intervened studies are needed to establish evidences.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.629-635
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• 2002

This study was performed to develop low-fat comminuted sausages (LFSs, < 3%) manufactured with 1% single (Konjac flour, KF; kappa-carrageenan, k-CN and Locust bean gum, LBG) or mixed hydrocolloids and to select the best combination which had similar textural characteristics to those with regular-fat (~25% fat) control. In experiment 1, LFSs were formulated with each 1% hydrocolloid, smoked and cooked to an internal temperature of 71.7$^{\circ}C$. The pH range of LFSs was 6.29 to 6.34 and approximately 23~24% of fat was removed in the final products, resulting in the higher moisture and protein contents (%) in LFSs, as compared to regular-fat control. No differences (p>0.05) in cooking loss (CL, %), expressible moisture (EM, %), and hunter color values (L, a, b) were observed with the addition of each 1% hydrocolloid. However, LFSs containing 1% k-CN had textural hardness values similar to those with low-/regular-fat controls, whereas LFSs having either KF or LBG had similar cohesiveness values to those with regular-fat counterpart. Tn experiment 2, two or three mixed hydrocolloids were added to the low-fat sausage formulation. The addition of mixed KF+LBG (KLL) and KF+CN+LBG(KCL) reduced EM and textural hardness values, as compared to low-fat control. Among the treatments, LFSs containing two or three combinations of CN with KF or/and LBG had similar textural characteristics to those with regular-fat control. These results suggested that multiple addition of CN with other hydrocolloids (KF or LBG) for the replacement of fats in LFSs would be recommended for the proper functional and textural properties.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.29 no.2 s.43
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• pp.205-232
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• 2003

Ursolic acid (UA) and Oleanolic acid (ONA), known as urson, micromerol and malol, are pentacyclic triterpenoid compounds which naturally occur in a large number of vegetarian foods, medicinal herbs, and plants. They may occur in their free acid form or as aglycones for triterpenoid saponins, which are comprised of a triterpenoid aglycone, linked to one or more sugar moieties. Therefore UA and ONA are similar in pharmacological activity. Lately scientific research, which led to the identification of UA and ONA, revealed that several pharmacological effects, such as antitumor, hepato-protective, anti-inflammatory, anticarcinogenic, antimicrobial, and anti-hyperlipidemic could be attributed to UA and ONA. Here, we introduced the effect of UA and ONA on acutely barrier disrupted and normal hairless mouse skin. To evaluate the effects of UA and ONA on epidermal permeability barrier recovery, both flanks of 8-12 week-old hairless mice were topically treated with either 0.01-0.1 mg/ml UA or 0.1-1 mg/ml ONA after tape stripping, and TEWL (Transepidermal water loss) was measured . The recovery rate increased in those UA or ONA treated groups (0.1 mg/ml UA and 0.5 mg/ml ONA) at 6 h more than $20\%$ compared to vehicle treated group (p<0.05). Here, we introduced the effects of UA and ONA on acute barrier disruption and normal epidermal permeability barrier function. For verifying the effects of UA and ONA on normal epidermal barrier, hydration and TEWL were measured for 1 and 3 weeks after UA and ONA applications (2mg/ml per day). We also investigated the features of epidermis and dermis using electron microscopy (EM) and light microscopy (LM). Both samples increased hydration compared to vehicle group from f week without TEWL alteration (p<0.005). EM examination using RuO4 and OsO4 fixation revealed that secretion and numbers of lamellar bodies and complete formation of lipid bilayers were most prominent $(ONA{\geq}UA>Vehicle)$. LM finding showed that thickness of stratum corneum (SC) was slightly increased and especially epidermal thickening and flattening was observed (UA>ONA>Veh). We also observed that UA and ONA stimulate epidermal keratinocyte differentiation via $PPAR\;\alpha$. Protein expression of involucrin, loricrin, and filaggrin increased at least 2 and 3 fold in HaCaT cells treated with either $ONA\;(10{\mu}M)$ or UA $(10{\mu}M)$ for 24h respectively. This result suggested that the UA and ONA can improve epidermal permeability barrier function and induce the epidermal keratinocyte differentiation via $PPAR\;{\alpha}$. Using Masson-trichrome and elastic fiber staining, we observed collagen thickening and elastic fiber elongation by UA and ONA treatments. In vitro results of collagen and elastin synthesis and elastase inhibitory activity measurements were also confirmed in vivo findings. These data suggested that the effects of UA and ONA related to not only epidermal permeability barrier functions but also dermal collagen and elastic fiber synthesis. Taken together, UA and ONA can be relevant candidates to improve epidermal and dermal functions and pertinent agents for cosmeseutical applications.