• 항공우주기술
• /
• 제6권1호
• /
• pp.83-91
• /
• 2007

위성용 RF 수동 소자에 대한 MP(multipactor) 현상과 그 검출 방법에 대한 연구를 수행하였으며, 본 연구에 사용된 RF 수동 소자는 S 대역 diplexer로, 이는 인터디지털 타입의 5단 chebyshev 응답특성을 갖는 두개의 대역통과필터로 구성되며 2.232 및 2.055 GHz 대역에서 2.7 %의 대역폭을 갖는 구조로 각각 설계되었다. MP 민감도 해석을 위해 diplexer에 대하여 3D 전자기 모델링을 수행하였으며, 이를 통하여 diplexer 구조적으로 multipactor에 대하여 가장 민감한 부분을 정의 하였고 이때의 MP 방전 현상이 나타나지 않는 최대 RF 입력전력을 규명하였다. 또한 KARI 자체 개발한 MP 민감도 시험 시설을 이용하여 QM용 diplexer에 대한 시험을 수행하였으며, 그 결과 CW 모드에서 43 dBm, 펄스 모드 시험에서 44 dBm의 RF 입력 전력에서 MP가 발생됨을 확인 하였다.

• 한국정보통신설비학회:학술대회논문집
• /
• 한국정보통신설비학회 2007년도 학술대회
• /
• pp.415-418
• /
• 2007

This paper presents the design and analysis of LNA-Mixer for 2.45GHz RFID reader. The LNA is implemented by PCSNIM method for low power consumption. The Mixer is implemented by using the Gilbert-type configuration, current bleeding technique, and the resonating technique for the tail capacitance. The connection between the two designed circuits is made by active balun. This LNA-Mixer has about 35dB for -40dBm input RF power, LO power is 0dBm and RF frequency is 2.45 GHz and IIP3 is -4dBm. The layout of LNA-Mixer for one-chip design in a $0.18-{\mu}m$ TSMC process has 2.6mm ${\times}$ 1.3mm size.

• Journal of information and communication convergence engineering
• /
• 제3권3호
• /
• pp.146-151
• /
• 2005

This paper represents an attempt to bring together and analyses the measurement data measured by the Satellite Signal Monitoring Center in Korea and the Korea Meteorological Administration/Korea Meteorological Research Institute in close cooperation with this study team. This paper presents the signal characteristic of GEO satellite operating in frequency range 1 to 20GHz associated with Asian Sand Dust (the so-called Yellow Sand Dust). The downlink signal power (dBm) for L-, S-, C-, Ku-, and Ka-band frequencies from GEO satellites were measured in a clear weather and in Asian Sand Dust weather by the Satellite Signal Monitoring Center. The measured signal power(dBm) were compared to the total number concentration and size distribution of Sand Dust that were measured by the Korea Meteorological Administration/Korea Meteorological Research Institute and the possible correlation between these sets data were analyzed. The results demonstrate that the downlink signal level (dBm) of GEO satellite is attenuated by Asian Sand Dust. Hitherto, merger information has been reported as to the influence of sand dust on satellite communications operating in regions affected by sand dust.

• 한국축산식품학회지
• /
• 제34권2호
• /
• pp.252-256
• /
• 2014

The objective of this study was to investigate the effect of dietary supplementation of blood meal as a source of L-histidine, and the addition of magnesium (Mg) as a catalyst of carnosine synthetase for the carnosine and anserine concentrations of pig muscles (longissimus dorsi, LD and vastus intermedius, VI). A total of twenty-four pigs with an average body weight of $60.2{\pm}4.2$ kg were randomly allotted to one of three dietary treatments (eight replicates), during 56 d of the feeding trial. Dietary treatments included: (1) Basal: basal diet; (2) BM: 95% basal diet + 5% blood meal; and (3) BM+Mg: 94.8% basal diet + 5% blood meal + 0.2% MgO (60% Mg). Results indicated that drip loss in the LD was less (p<0.05) for meat with BM+Mg treatment than that with Basal treatment, but the values for BM treatment did not differ from those of the other two treatment groups. The concentrations of carnosine in the LD were increased by 10.0% in both BM and BM+Mg treatment groups over the Basal treatment group (significance not verified). The concentrations of carnosine and anserine in the VI were not affected by the dietary treatments. Inclusion of additional Mg in diets had no effect on carnosine and anserine concentrations in the LD and VI. In conclusion, dietary supplementation of blood meal could be a potential method of fortifying the pork with carnosine. Inclusion of additional Mg in the diets containing blood meal had no benefit on carnosine and anserine depositions in pig muscles.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제3권1호
• /
• pp.13-18
• /
• 2001

The role of polyhedrin in the polyhedra production in baculovirus Autograha californica Nucelopolyhedro-sisvirus (AcNPV) was studied by over-expression of AcNPV polyhedrin or heterologous polyhedrin from Bombyx mori (Bm) NPV or Spodoptera exigua (Se) NPV. The transfer vectors containing additional polyhedrin from AcNPV, BmNPV, or SeNPV were constructed and cotransfected with bacmid bApGOZA into Sf9 cells. The resulting recombinants, designated as vApAcPol, vApBmPol, and vApSePol were tonstructed, and the polyhedra production of the recombinant was characterized. All of the recombinants produced polyhedra in the nucleus, and the polyhedrin was over-expressed. Among three recombinants, vApAcPol and vApBmPol were discriminated by their larger polyhedra size than that of wild type AcNPV, and vApSePol also produced larger polyhedra than wild type SeNPV polyhedra.

• Asian-Australasian Journal of Animal Sciences
• /
• 제15권5호
• /
• pp.721-724
• /
• 2002

Postmortem Proteolysis of breast (BM) and leg (LM) muscles in Chiayi native chickens at $5^{\circ}C$ were compared. Myofibrils were purified from BM and LM samples that were randomly taken from carcasses after 0, 1, 3, 7 and 14 days of storage at $5^{\circ}C$. Fragmentation of myofibrils were determined, and degradation of myofibrillar proteins were analyzed by the SDS-PAGE and western blots. The results showed that myofibril fragmentation index (MFI) was significantly (p<0.05) higher in BM than in LM samples. Disappearance of titin and nebulin and appearance of the 30 kDa component were more rapidly as seen on SDS-PAGE in BM than in LM samples. Western blots labeled with a monoclonal antibody to desmin also demonstrated that desmin degraded more quickly in BM samples. Our data suggested that postmortem proteolysis occurred more rapidly in breast muscles in Chiayi native chickens.

• BMB Reports
• /
• 제57권5호
• /
• pp.238-243
• /
• 2024

Bone marrow-derived mesenchymal stem cells (BM-MSCs) can differentiate into endothelial cells in an inflammatory microenvironment. However, the regulatory mechanisms underlying this process are not entirely understood. Here, we found that TIE2 in BM-MSCs was upregulated at the transcriptional level after stimulation with tumor necrosis factor-alpha (TNFα), a major pro-inflammatory cytokine. Additionally, the STAT-binding sequence within the proximal region of TIE2 was necessary for TNFα-induced TIE2 promoter activation. TIE2 and STAT3 knockdown reduced TNFα-induced endothelial tube formation in BM-MSCs. Among the major TNFα-activated MAP kinases (ERK1/2, JNK1/2, and p38 MAPK) in BM-MSCs, only inhibition of the p38 kinase abrogated TNFα-induced TIE2 upregulation by inhibiting the JAK-STAT signaling pathway. These findings suggest that p38 MAP contributes to the endothelial differentiation of BM-MSCs by activating the JAK-STAT-TIE2 signaling axis in the inflammatory microenvironment.

• 전기학회논문지
• /
• 제58권5호
• /
• pp.999-1003
• /
• 2009

We have designed and fabricated a linear drive amplifier with a novel intermodulation distortion(IMD) canceller using $0.18{\mu}m$ CMOS process. The drive amplifier with IMD canceller is composed of a cascode main amplifier and an additional common-source IMD canceller. Since the IMD canceller generates IM3($3^{rd}$-order imtermodulation) signal with $180^{\circ}$ phase difference against the IM3 of the cascode main amplifier, the IM3 power is drastically eliminated. As of the measurement results, $OP_{1dB}$, $OIP_3$, and power-add efficiency are 5.5 dBm, 15.5 dBm, and 21%, respectively. Those are 5 dB, 6 dB, and 13.5% enhanced values compared to a conventional cascode drive amplifier. The IMD3 of the drive amplifier with IMD canceller is enhanced more than 10 dB compared to that of the conventional cascode drive amplifier for input power ranges from -22 to -14 dBm.

• Asian Pacific Journal of Cancer Prevention
• /
• 제17권3호
• /
• pp.1405-1410
• /
• 2016

Background: The European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Bone Metastases Module (EORTC QLQ-BM22) is a recently designed supplement to EORTC Quality of Life Questionnaire-C30 (EORTC QLQ-C30). Additional psychometric properties, especially using confirmatory factor analysis (CFA) and the Rasch model, are warranted. Materials and Methods: A total of 573 patients with bone metastases were enrolled from eight countries with a mean${\pm}$SD age of $55.8{\pm}13.7years$. Slightly more than two thirds of them were female (n=383; 66.8%). CFA was used to examine the BM22 framework; Rasch models were applied to understand misfit items and differential item functioning (DIF). Results: The fit indices were satisfactory in CFA (comparative fit index=0.972, Tucker-Lewis index=0.964, root mean square error of approximation=0.076, and standardized root mean square residual=0.045). All items fit well in the Rasch models (mean square values were between 0.5 and 1.5), and only one item (number 17) displayed DIF across gender. However, there were six DIF items across Canada and Taiwan, ten across Canada and Iran, and six across Taiwan and Iran. Conclusions: The BM22 has satisfactory psychometric properties, and could assess the QoL of patients with bone metastases specifically focusing on their symptoms. Clinicians may want to use it to capture the underlying QoL for patients with bone metastases. However, the score of item 17 should be interpreted with caution when comparing male and female patients. In addition, researchers should note that variation in DIF items may occur when conducting an international study.

• 한국전자파학회:학술대회논문집
• /
• 한국전자파학회 2000년도 종합학술발표회 논문집 Vol.10 No.1
• /
• pp.175-178
• /
• 2000

본 연구에서는 CDMA단말기용 Receiver MMIC를 설계하였다. 전체회로는 저잡음 증폭기, 하향 주파수 혼합기 그리고 중간주파수 증폭기로 구성된다. 또한 문턱전압과 전원전압의 변화에 대해 회로의 안정성을 높이는 바이어스 보상회로를 추가하였다. 설계시 높은 선형성과 저잡음 특성을 가지도록 토폴리기를 구성하였고 설계 결과 전체 이득은 28.5dB, 저잡음 증폭기의 입력IP3는 8dBm, 하향주파수 혼합기의 입력 IP3는 0dBm이며 전체회로의 소모전류는 22.1mA이다. 레이아웃된 전체회로의 크기는 1.4$\times$1.4 [$\textrm{mm}^2$] 이다.