• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.235-237
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• 2008

A unified hydrocode, ExLO, in which Largrangian, ALE and Eulerian solvers are incorporated into a single framework, has recently been developed in Korea. It is based on the three dimensional explicit finite element method and written in C++. ExLO is mainly designed for the calculation of structural responses to highly transient loading conditions, such as high-speed impacts, high-speed machining, high speed forming and explosions. In this paper the numerical schemes are described. Some improvements of the material interface and advection scheme are included. Details and issues of the momentum advection scheme are provided. In this paper the modeling capability of ExLO has been described for two extreme loading events; high-speed impacts and explosions. Numerical predictions are in good agreement with the existing experimental data. Specific applications of the code are discussed in a separate paper in this journal. Eventually ExLO will be providing an optimum simulation environment to engineering problems including the fluid-structure interaction problems, since it allows regions of a problem to be modeled with Lagrangian, ALE or Eulerian schemes in a single framework.

• Toxicological Research
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• v.32 no.2
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• pp.103-108
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• 2016

The purpose of this study was to determine the hair growth effects of lavender oil (LO) in female C57BL/6 mice. The experimental animals were divided into a normal group (N: saline), a vehicle control group (VC: jojoba oil), a positive control group (PC: 3% minoxidil), experimental group 1 (E1: 3% LO), and experimental group 2 (E2: 5% LO). Test compound solutions were topically applied to the backs of the mice ($100{\mu}L$ per application), once per day, 5 times a week, for 4 weeks. The changes in hair follicle number, dermal thickness, and hair follicle depth were observed in skin tissues stained with hematoxylin and eosin, and the number of mast cells was measured in the dermal and hypodermal layers stained with toluidine blue. PC, E1, and E2 groups showed a significantly increased number of hair follicles, deepened hair follicle depth, and thickened dermal layer, along with a significantly decreased number of mast cells compared to the N group. These results indicated that LO has a marked hair growth-promoting effect, as observed morphologically and histologically. There was no significant difference in the weight of the thymus among the groups. However, both absolute and relative weights of the spleen were significantly higher in the PC group than in the N, VC, E1, or E2 group at week 4. Thus, LO could be practically applied as a hair growth-promoting agent.

• Korean journal of applied entomology
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• v.38 no.2
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• pp.123-128
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• 1999

Recently, entomopathogenic nematodes have received a considerable attention as biologicalcontrol agents. For in vitro cultivation, storage and transportation of nematodes, oxygen supply isextremely impotant due to its limited solubility and mass transfer problem. The oxygen uptake rates(OURs) of four different Steinernema species were measured in a 5L bioreactor at varying temperatures.The OURs of the Steinernema spp. were below 0.5 x mmolO'||'&'||' . min in the range of 13-17$^{\circ}$C. TheOURs (mmo102/L - min) of S. glaseri Dongrae and S. carpocapsae Pocheon strains were 0.4 x lo-', 0.75x lo-\ulcorner at 21$^{\circ}$C, 1.5 x lo-\ulcorner, 3.2 x 10-2 at 25"C, and 2.8 x lo-', 5.8 x lo-\ulcorner at 29"C, respectively. However,the OURs were not significantly altered by the agitation speed of 50-150 rpm. The specific oxygenuptake rates (qol) of S. glaseri NC, S. glaseri Dongrae, S. glaseri Mungyeong and S. carpocapsaePocheon strains were 0.3 x 0.5 x 0.3 x and 0.2 x mmolO~/cell min at 25"C,respectively. As the nematode size and temperature were increased, the qo, was also increased.the qo, was also increased.

• Applied Microscopy
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• v.46 no.3
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• pp.140-149
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• 2016

This study intended to compare the effects of the sugar-Omija extract tea (SO) and LuoHanGuo-Omija extract tea (LO) to blood glucose levels and metabolism among streptozotocin (STZ)-induced diabetic mice and to prove the positive effects of LuoHanGuo extract as a sugar substitute. According to the results, the rate of blood glucose increase and the blood glucose level was reduced, and the weight was increased. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglyceride, low density lipoprotein cholesterol, and total cholesterol was decreased, and albumin, total protein, and high density lipoprotein cholesterol (HDL-C) was increased in the STZ/LO group as compared to the STZ group. Compared to the STZ/SO group, the rate of blood glucose increase and glucose tolerance was decreased. AST, ALT, and total cholesterol was decreased, and HDL-C level was high. In conclusion, the LO displayed hypoglycemic effect, prevented weight loss caused by diabetes, recovered liver function, and improved lipid metabolism. In addition, such positive effects were obviously shown during comparison with the experimental group treated with the SO. Therefore, the LO were considered as favorable food supplements that can be safely taken by persons with diabetes, obesity, hypertension, and heart disease; they have to control their sugar intake as well as their diet.

• Proceedings of the IEEK Conference
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• 2004.06a
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• pp.205-208
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• 2004

본 논문에서는 직접 변환 방식의 가장 큰 문제점 중 하나인 DC 오프셋 문제를 개선하기 위한 방안으로, 서브 하모닉 저항성 믹서를 GaAs FET 소자를 이용하여 제작하였다. 측정된 결과 LO 주파수의 2 차 하모닉 성분을 이용하는 특성상 변환이득은 일반 믹서보다 큰 -15.0dB의 특성을 얻었다. 또한 별도의 대역통과 여파기를 사용하지 않고도 LO-IF 및 LO-RF 분리도 특성은 최소 48.2dB와 77.8dB의 양호한 특성을 나타내었다.

• Proceedings of the IEEK Conference
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• 2003.07a
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• pp.346-349
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• 2003

A SiGe HBT MMIC double balaced up-converter has been designed and fabricated for C-band WLAN applications. The up-converter is based on the Gilbert cell mixer with an active baluns for differential inputs of LO and IF signals. The designed up-converter exhibits a conversion gain 12.5dB for a -10 dBm LO power. It also exhibits LO-RF isolation of 19.3dBc, and IF-RF isolation of 23.3 dBc at a 1-dB compression point of -14.2dBm

• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.121-122
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• 1998

Raman 분광학을 이용하여 질화된 GaAs 박막의 특성을 조사 하였다. GaAs 질화 과 정은 상온에서부터 $600^{\circ}C$까지의 여러 가지 온도에서 ECR질소 플라즈마를 조사함으로써 시 료를 준비하였다. Raman 측정의 결과 온도가 증가함에 따라 세로 광학(LO) 포논 및 가로 광학 (TO) 포논모드의 진동수는 낮은 진동수로 이동하였고 또한 LO-TO 분리 크기 역시 감소하였다. 진동수의 이동의 근원을 격자상수의 변화에 따른 변형 및 유효전하의 감소등으 로 설명하였다. LO 포논 모드의 밴드 폭의 넓어어지는 $600^{\circ}C$에서 가장 컸으며 이는 고온에 서 표면의 무질서 구조가 가장 많이 일어났음을 뜻한다. 이와 같은 원인으로 질화된 GaAs 박막의 몇 가지 물리적 변수인 결함의 비율, 변형의 크기 및 상관 길이 등을 계산하였다.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.193-196
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• 2000

본 논문에서는 FG-CPW(Finite-Ground Coplanar Wave-Guide) 구조의 단일 평형 다이오드 믹서에 대해서 논의된다. 주파수 영역은 무선 LAN 대역으로 선택하였다. RF 신호는 5.725-5.875 GHz, LO 신호는 5.58GHz, 그리고 IF 신호는 140 MHz가 사용된다. 제시된 FG-CPW 구조의 LPF(low pass filter)는 회의크기를 줄일 수 있으며, 불필요한 하모닉 억제 특성이 우수하다. 5.635 GHz에서 5 dBm의 Power를 갖는 LO신호가 입력될 때 6.2 dB 의 혼합기의 변환손실을 얻는다. 또한 LO-RF isolation과 LO-IF isolation은 각각 30 dB $\Omega$dB 의 특성을 보인다. 이 혼합기는 CPW 구조가 일반적으로 알려진 밀리미터 대역에서의 장점뿐만 아니라 C-Band의 무선 LAN 분야에도 충분히 응용될 수 있으리라 기대된다.

• KIEE International Transactions on Electrophysics and Applications
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• v.4C no.6
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• pp.272-275
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• 2004

A balanced single side-band (SSB) mixer employing a sub-harmonic configuration is designed for up and down conversions in K-band. The designed mixer uses anti-parallel diode (APD) pairs to effectively eliminate even harmonics of the local oscillator (LO) spurious signal. To reduce the odd harmonics of LO at the RF port, we employ a balanced configuration for LO. The fabricated chip shows 12$\pm$2dB of conversion loss and image-rejection ratio of about 20dB for down conversion at RF frequencies of 24-27.5GHz. As an up-conversion mode, the designed chip shows 12dB of conversion loss and image-rejection ratio of 20 ～ 25 dB at RF frequencies of 25 to 27GHz. The odd harmonics of the LO are measured below -37dBc.

• Journal of Practical Agriculture & Fisheries Research
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• v.23 no.2
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• pp.25-32
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• 2021

There is a need to breed and distribute of domestic varieties for Lilium longiflorum because most of the lily bulbs cultivated in Korea were imported from foreign country. The L. longiflorum 'Ace' and 'Nellie White' collected from 1996 had been self-crossed from 1996 to 2010. In 2012, the L. longiflorum 'Bright LoSong' was developed as a F₁ hybrid crossed between 'L₂-17-4' and 'L₂-16-6' that obtained by 7th self-fertilization. The 'Bright LoSong' was tested for homogeneity, regional adaptability test, consumer preference show from 2014 to 2015, and it was registered in 2017. The flower of 'Bright LoSong' is a trumpet shaped single flower with no spots.It has 5.8 flowers per plant, which is a relatively many number compared control 'Mount Carmel', Its flower diamater is 9.8cm, relatively a bit small size. And the flower inflorescence has umbel or raceme while the attitude of longitudinal axis is horizontal. The plant height is 38.4cm with 30.8 leaves per plant and 1.9cm of the leaf width. 'Bright LoSong' has a longer flowering period because of relatively small diameter or many number of flowers than those of the control 'Mount Carmel'. Thus, the 'Bright LoSong' showed a high consumer preference, and the cultivar has the advantage of being able to reproduce since the parents are pure lines.