• 한국전자파학회논문지
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• 제25권10호
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• pp.1062-1068
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• 2014

본 논문에서는 두 개의 순차적인 inverse synthetic aperture radar(ISAR) 영상들을 활용하여 표적의 회전 속도(Rotation Velocity: RV) 추정을 통한 수직 거리 스케일링(cross-range scaling: CRS)을 수행한다. 순차적으로 형성된 두 개의 ISAR 영상들에 각각 scale invariant feature transform(SIFT)를 적용함으로써 관측각도의 변화에 강인한 산란원(scatterer)들을 추출한다. 추출된 산란원과 각 영상 내 표적의 회전 중심(Rotation Center: RC) 사이의 거리가 같다는 점을 이용하여 비용함수(cost function)를 설정한 후, 전역 탐색 기법(exhaustive search method)과 결합된 particle swarm optimization(PSO)의 최적화를 통해 표적의 RV를 RC 정보 없이 추정한다. 시뮬레이션에서는 시나리오 기반으로 기동하는 표적에 대한 ISAR 영상 형성 후, 제안된 기법을 통해 RC의 정보 없이 RV를 추정함으로써 ISAR 영상의 CRS가 성공적으로 수행됨을 보여준다.

• Korean Journal of Radiology
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• 제21권4호
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• pp.450-461
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• 2020

Objective: We performed a meta-analysis to evaluate the agreement of cardiac computed tomography (CT) with cardiac magnetic resonance imaging (CMRI) in the assessment of right ventricle (RV) volume and functional parameters. Materials and Methods: PubMed, EMBASE, and Cochrane library were systematically searched for studies that compared CT with CMRI as the reference standard for measurement of the following RV parameters: end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), or ejection fraction (EF). Meta-analytic methods were utilized to determine the pooled weighted bias, limits of agreement (LOA), and correlation coefficient (r) between CT and CMRI. Heterogeneity was also assessed. Subgroup analyses were performed based on the probable factors affecting measurement of RV volume: CT contrast protocol, number of CT slices, CT reconstruction interval, CT volumetry, and segmentation methods. Results: A total of 766 patients from 20 studies were included. Pooled bias and LOA were 3.1 mL (-5.7 to 11.8 mL), 3.6 mL (-4.0 to 11.2 mL), -0.4 mL (5.7 to 5.0 mL), and -1.8% (-5.7 to 2.2%) for EDV, ESV, SV, and EF, respectively. Pooled correlation coefficients were very strong for the RV parameters (r = 0.87-0.93). Heterogeneity was observed in the studies (I² > 50%, p < 0.1). In the subgroup analysis, an RV-dedicated contrast protocol, ≥ 64 CT slices, CT volumetry with the Simpson's method, and inclusion of the papillary muscle and trabeculation had a lower pooled bias and narrower LOA. Conclusion: Cardiac CT accurately measures RV volume and function, with an acceptable range of bias and LOA and strong correlation with CMRI findings. The RV-dedicated CT contrast protocol, ≥ 64 CT slices, and use of the same CT volumetry method as CMRI can improve agreement with CMRI.

• Pediatric Infection and Vaccine
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• 제26권2호
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• pp.99-111
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• 2019

목적: 호흡기세포융합바이러스(RSV)와 라이노바이러스(hRV)는 소아의 호흡기 바이러스감염의 가장 흔한 원인이다. 본 연구는 RSV 혹은 hRV 감염으로 입원하는 소아의 역학, 임상적 특성, 혈액 검사 결과를 분석하고, 각 바이러스 단독 감염과 동시 감염 간의 임상적 특성 및 혈액 검사 결과를 비교하고자 하였다. 방법: 2014년 10월부터 2017년 4월까지 매년 10월부터 4월 사이에 원주세브란스기독병원 소아청소년과에 호흡기 증상으로 입원한 만 5세 미만의 환아 중, 비강인두도말 검체로 다중 역전사 실시간 중합효소연쇄반응 검사를 시행하여 RSV 혹은 hRV가 검출된 사례를 대상으로 의무기록을 후향적으로 분석하였다. 결과: 강원 지역 소아 호흡기 환자의 multiplex RT-PCR 바이러스 검출 패턴 상, RSV는 늦가을부터 초봄 사이, hRV는 연중 고르게 분포하였다. RSV 혹은 hRV가 검출된 총 384례 중 RSV는 258례(R group), hRV는 99례(H group)에서 단독으로 검출되었고, RSV와 hRV의 동시 검출은 27례에서 있었다(RH group). R군의 연령 중앙값은 6개월이었으며, 248례(96.1%)가 하기도 감염이었다. 산소치료는 14례(5.4%)에서 있었다. 12개월 미만의 영아가 반수 이상을 차지하였고(63.2%) 호흡곤란, 산소치료가 많았다. H군의 연령 중앙값은 16개월이었으며, 56례(56.6%)가 하기도 감염이었다. 산소치료는 4례(4.0%), 기계 호흡은 1례(1.0%)에서 시행하였다. 영아(40.4%)는 12개월 이상 환자보다 재원기간이 길었다(5 vs. 4 days, P<0.05). RH군의 경우 24례(88.9%)가 하기도 감염이었고, 산소치료는 2례(7.4%)에서 있었다. RH군은 R군 및 H군과 비교하여 재원기간, 산소치료 및 기계 호흡의 비율에 차이가 없어, 동시 감염과 단독 감염의 유의한 중증도 차이는 없는 것으로 나타났다. 결론: RSV는 hRV보다 더 어린 연령에서 잘 이환되고 하기도 감염의 비율이 높았다. 동시 감염된 환자의 임상증상은 RSV 감염의 특성이 보다 반영되었고, 단독 감염에 비해 중증도에 차이는 없었다.

• 한국식품영양학회지
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• 제30권6호
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• pp.1348-1358
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• 2017

To enhance the physiological activity of the Rhynchosia volubilis (RV), R. volubilis (RVHE-A) and R. volubilis-added herbal powder (RVHE-B) were fermented with a solid state culture of Hericium erinaceum mycelia (HE). The total isoflavone contents of the non-fermented RV-A ($489.9{\mu}g/g$) and RV-B ($571.1{\mu}g/g$) were remarkably increased in fermented RVHE-A ($1,836.4{\mu}g/g$) and RVHE-B ($1,276.7{\mu}g/g$). In particular, aglycone isoflavones such as daidzein and genistein were significantly higher in the RVHE-A than any other sample. When hot-water (HW) and EtOH extracts (E) were fractionated from the RV and RVHE, both extracts from the RVHE-A were higher than those from the RV-A in total polyphenol and flavonoid contents. However, the RVHE-B-HW showed a lower polyphenol and flavonoid content level than did RV-B-HW. RVHE-A-HW and -E also had more potent ABTS radical scavenging activity than any extract from the non-fermented RV and other ferments (RVHE-B). In the meanwhile, RVHE-A-HW potently stimulated the production of macrophage activation-related cytokines such as $TNF-{\alpha}$, IL-6 and IL-12 ($841.7{\pm}71.3pg/mL$, $3.9{\pm}0.1ng/mL$, $179.3{\pm}30.2pg/mL$) from peritoneal macrophage more than RV-A-HW ($92.5{\pm}1.5pg/mL$, $0.1{\pm}0.0ng/mL$, $37.4{\pm}5.4pg/mL$) as well as RVHE-B-HW ($557.0{\pm}21.3pg/mL$, $1.8{\pm}0.0ng/mL$, $90.0{\pm}10.0pg/mL$). However, all the EtOH extracts did not show significant activity. In addition, the RVHE-A-HW showed a significantly higher intestinal immune system modulating activity through Peyer's patch and GM-CSF production than did any other extract from RV and RVHE-B. In conclusion, these results suggest that the fermented R. volubilis with H. erinaceum mycelia possesses a possible use as an industrial application as functional food or material.

• 천문학회지
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• 제51권1호
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• pp.17-25
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• 2018

Detecting exoplanets around giant stars sheds light on the later-stage evolution of planetary systems. We observed the M giant HD 18438 and the K giant HD 158996 as part of a Search for Exoplanets around Northern circumpolar Stars (SENS) and obtained 38 and 24 spectra from 2010 to 2017 using the high-resolution Bohyunsan Observatory Echelle Spectrograph (BOES) at the 1.8m telescope of Bohyunsan Optical Astronomy Observatory in Korea. We obtained precise RV measurements from the spectra and found long-period radial velocity (RV) variations with period 719.0 days for HD 18438 and 820.2 days for HD 158996. We checked the chromospheric activities using Ca $\text\tiny{II}$ H and $H{\alpha}$ lines, HIPPARCOS photometry and line bisectors to identify the origin of the observed RV variations. In the case of HD 18438, we conclude that the observed RV variations with period 719.0 days are likely to be caused by the pulsations because the periods of HIPPARCOS photometric and $H{\alpha}$ EW variations for HD 18438 are similar to that of RV variations in Lomb-Scargle periodogram, and there are no correlations between bisectors and RV measurements. In the case of HD 158996, on the other hand, we did not find any similarity in the respective periodograms nor any correlation between RV variations and line bisector variations. In addition, the probability that the real rotational period can be as longer than the RV period for HD 158996 is only about 4.3%. Thus we conclude that observed RV variations with a period of 820.2 days of HD 158996 are caused by a planetary companion, which has the minimum mass of 14.0 $M_{Jup}$, the semi-major axis of 2.1 AU, and eccentricity of 0.13 assuming the stellar mass of $1.8 M_{\odot}$. HD 158996 is so far one of the brightest and largest stars to harbor an exoplanet candidate.

• BMB Reports
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• 제29권2호
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• pp.99-104
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• 1996

Site-directed substitutions were made to change the Ile91 of restriction endonuclease EcoRV to either Val, Ala or Gly to identify the role of Ile91 in recognition and catalysis, since substitution of Ile91 with Leu afforded dramatic effects on the activity and properties of restriction endonuclease EcoRV. These changes alter the size of the hydrophobic side chain at position 91 and thus might have revealed the reason for the altered phenotype of Ile91Leu. However, the properties of Ile91Val and Ile91Ala mutants were much like wild type EcoRV, in both activity and metal ion preference. Ile91Gly had very little activity with either $Mg^{2+}$ or $Mn^{2+}$ as cofactors. To try to understand the unusual $Mn^{2+}$ profile of the Ile91Leu mutant, two double mutants, Ile91Leu;Asp90Asn and Ile91Leu;Glu45Met were created. Both double mutants were seriously disabled by the second amino acid change. Ile91Leu;Glu45Met had some residual activity in the $Mn^{2+}$ reaction buffer, whereas the Ile91Leu;Asp90Asn displayed no detectable activity.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 추계학술대회 논문집 전력기술부문
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• pp.9-11
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• 2008

A protection current transformer (CT) has been widely used for protection devices. When a fault occurs, a CT should provide the faithful reproduction of the primary fault current. However, a CT may saturates due to the magnitude of fault current, dc component primary time constant and the remanent flux of the iron core, and the secondary current of a CT is distorted. The distorted current can cause mal-operation or the operating time delay of a protection relay. This paper provides a modeling of CT saturation using EMTP-RV. The performance of the proposed CT saturation modeling was investigated under various fault conditions varying the fault distance, fault inception angle, and remanent flux of the iron core. The results indicate that the proposed EMTP-RV modeling can operate correctly, and the reasons for CT saturation are verified by EMTP-RV simulations.

• Journal of Chest Surgery
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• 제7권2호
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• pp.201-208
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• 1974

The purpose of this paper is to present author's experience with 6 cases of ruptured aneurysm of sinus of Valsalva which were treated surgically during last 10 years. Among the 6 cases, 5 were male and one was female. All of them originated from the right coronary sinus and 5 cases were ruptured into the RV while remained one into RA. The diagnosis was obtained in 4 cases by cineangiocardiogram. Clinically, we had difficulties in differential diagnosis with combined cases of VSD with A.I. and had special experience in its differentiation during cardiac catheterization. By simultaneous trans-venous and trans-arterial catheterization, identified two catheter tips in the RV, and pull back tracing obtained aortic pressure directly from RV, and RA from RV pressure which were benefit in confirm ruptured aneurysm of the aortic sinus. Surgical correction was performed by means of direct suture closure or combined Teflon pledget Of patch enforcement graft after aneurysm resection by trans-RA or trans-RV approach. All patients had no history of bacterial endocarditis, syphilis, or tuberculosis and operative findings revealed intact coronary sinus except involved one moreover 3 cases combined with high VSD which uggested congenital in origin although pathologic reports revealed only fibrosis. Post-operative course were uneventful in all cases but one who had bleeding and 2 months to 9 years follow up results were good and spend their usual life in all cases.

• 디자인학연구
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• 제14권4호
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• pp.35-45
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• 2001

The origin of Minivan styled RV dates all the way back to the year 1959 when Volkswagen introduced the Microbus in Germany. But the new category of "Minivan" was made, and first used by Chrysler. This was when Chrysler revealed a new vehicle in 1982 named "Minivan". Minivan was successful in gathering the public attention with it′s multi-purpose characteristic. Ever since, many models were introduced in this category by various auto-makers around the world, which made the Minivan segment very competitive. Various Minivans were also introduced by the Korean auto-makers and these models have been finding their place rapidly in the market owing to their unique characteristics. But the reason for the growth of the Minivan category in Korea was quite different from that of other nations. Through out this thesis, the possibilities of a Minivan that can full fill the needs of a new life style of a family in the basis of various documentary records will be discussed. Ways of making roads, where bigger sized Minivans are continuously increasing, more efficient will also be considered. The main topic of this thesis will be about Minivan styled RV(Recreational vehicle) in relation to the change of Korean life style.

• 천문학회보
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• 제35권2호
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• pp.78.2-78.2
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• 2010

We report the detection of a low-amplitude 380.8-day radial velocity (RV) variations in oscillating K2 III star ${\alpha}$ Ari (HD 12929). We do not found the correlation between RV variations and equivalent widths of chromospheric activity indicators ($H{\alpha}$ and CaII 8662 ${\AA}line$). The bisector analysis shows that bisector velocity span (BVS) and RV variations are not strongly correlated with each other. These result suggest that the RV variations could have been produced either by planetary companion or by the surface spots. If this RV variation is indeed caused by a planetary companion, an orbital solution with a period of P = 381 days, a semi-amplitude of K = 41 m/s, and an eccentricity of e = 0.25 fits the data best. Assuming a possible stellar mass of $M_{\bigstar} = 1.4-5.6 M\odot$, we estimate the minimum mass for the companion of m sini = 1.8-4.5 $M_{Jup}$ with an orbital semi-major axis of 1.2-1.9 AU. If confirmed, our finding gives a support to search for exoplanets around giant stars with multi-periodic oscillations.