• 제목/요약/키워드: HRG

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Avoidance of Internal Resonances in Hemispherical Resonator Assemblies from Fused Quartz Connected by Indium Solder

  • 세르게이 사라플로프;이희남;박상진
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2013년도 춘계학술대회 논문집
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    • pp.835-841
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    • 2013
  • Modern solid-state gyroscopes (HRG) with hemispherical resonators from high-purity quartz glass and special surface superfinishing and ultrathin gold coating become the best instruments for precise-grade inertial reference units (IRU) targeting long-term space missions. Designing of these sensors could be a notable contribution into development of Korea as a space nation. In participial, 40mm diameter thin-shell resonator from high-purity fused quartz, fabricated as a single-piece with its supporting stem has been designed, machined, etched, tuned, tested, and delivered by STM Co. (ATS of Ukraine) several years ago; an extremely-high Q-factor (upto 10~20 millions) has been shown. Understanding of the best way how to match such a unique sensor with inner glass assembly of the gyro means how to use the high potential in a maximal extent; and this has become the urgent task. Inner quartz glass assembly has a very thin indium (In) layer soldered the resonator and its silica base (case), but effects of internal resonances between operational modal pair of the shell-cup and its side (parasitic) modes can notable degrade the potential of the sensor as a whole, instead of so low level of resonator's intrinsic losses. Unfortunately, there are special combinations of dimensions of the parts (so-called, "resonant sizes"), when intensive losses of energy occurs. The authors proposed to use the length of stem's fixture as an additional design parameter to avoid such cases. So-called, a cyclic scheme of finite element method (FEM) and ANSYS software were employed to estimate different combinations of gyro assembly parameters. This variant has no mismatches of numerical origin due to FEM's discrete mesh. The optimum length and dangerous "resonant lengths" have been found. The special attention has been paid to analyses of 3D effects in a cup-stem transient zone, including determination of a difference between the positions of geometrical Pole of the resonant hemisphere and of its "dynamical Pole", i.e., its real zone of oscillation node. Boundary effects between the shell (cup) and 3D short "beams" (inner and outer stems) have been ranged. The results of the numerical experiments have been compared with the classic model of a quasi-hemispherical shell band with inextensional midsurface, and the solution using Rayleigh's functions of the $1^{st}$ and $2^{nd}$ kinds. To guarantee the truth of the recommended sizes to a designer of the real device, the analytical and FEM results have been compared with experimental data for a party of real resonators. The consistency of the results obtained by different means has been shown with errors less than 5%. The results notably differ from the data published earlier by different researchers.

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반구형공진기 실험장치 개발과 진동패턴 제어 (Development of a Test System for a Hemispherical Resonator and Control of Vibrating Pattern)

  • 김동국;윤형주;진재현
    • 한국항공우주학회지
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    • 제41권10호
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    • pp.813-819
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    • 2013
  • 본 논문에서는 반구형 공진자이로에 대한 연구를 위해 NI FPGA 장비를 기반으로 한 실험 장치를 개발하였고 공진유도, 진폭제어 및 회전실험을 통해 실험 장치에 대한 적합성을 판별하고 시스템에 대한 파라미터를 추정하였다. 또한 공진기의 형상 불 균일로 인해 진동패턴이 표류하는 현상을 확인하고, 이를 정렬시킴으로써 구동모드중 하나인 FTR 모드 구현에 대한 선행연구를 수행하였다.

반구형 공진 자이로의 동작모델과 기초 제어특성 실험 (Dynamic Models of Hemispherical Resonator Gyros and Tests of Basic Control Characteristics)

  • 진재현;최홍택;윤형주;김동국
    • 제어로봇시스템학회논문지
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    • 제19권10호
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    • pp.947-954
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    • 2013
  • This article focuses on a hemispherical resonator gyro driven by the Coriolis effect. The operational principle of resonator gyros and mathematical models are introduced. These models are useful to explain the behavior of a resonator and to design controllers. Several control tests of a resonator have been done. A resonator has been excited by electromagnets controlled by a computer. Its amplitude has been adjusted by a PI control. The transient response is matched with a simulation result based on a mathematical model. A vibrating pattern may drift due to non-uniform factors of a resonator. The drift of the vibrating pattern is controlled and aligned to a reference direction by a PI control. These results are very useful to understand the behavior of resonator gyros and to design advanced control algorithm for better performance.

The Development of Bluetooth Router Capable of Communication between Broadband Network and Slave Devices for Companion Animals

  • Kwak, Ho-Young;Kim, Woo-Chan;Chang, Jin-Wook
    • 한국컴퓨터정보학회논문지
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    • 제23권9호
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    • pp.51-56
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    • 2018
  • Currently, many households raise their companion animals for personal reasons. In this environment, the companion animal is left alone in the home, the owner of the companion animal is increasingly curious about the behavior pattern of the companion animal left alone, and there are many devices that can solve this question. In this paper, we have designed and implemented a Bluetooth-based slave device (beacon in this paper) and a router capable of connecting to a broadband network that can observe behavior patterns of companion animals by using advanced ICT technology. The Bluetooth router designed and implemented in this paper installs a beacon in the home, receives the beacon signal from the device and the beacon installed by the companion animal, and transmits the moving line of the companion animal to the owner of the companion animal through the broadband network, so that it can be confirmed in real time through the app for the provided smart phone.

The Image Processing System for Volume Gains Rate Measurement of Pigs

  • Kwak, Ho-Young;Chang, Jin-Wook
    • 한국컴퓨터정보학회논문지
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    • 제24권12호
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    • pp.127-134
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    • 2019
  • 본 논문에서는 양돈의 증체율을 영상 이미지를 이용하여 자동으로 측정하는 시스템을 설계하고 구현하였다. 양돈은 축사에서 사육되면서 육돈으로 출하하기 위해 양돈의 증체율이 목장주의 경제적 이익과 직결하기 때문에 매우 중요한 요소로 작용하고 있다. 따라서 양돈 개체별 증체율을 손쉽게 측정할 수 있는 방법이 요구되고 있어, 이를 위한 방법으로 양돈을 평면적으로 촬영하여 양돈의 증체율을 측정할 수 있는 영상 분석 알고리즘을 제시하였다. 또한 제시된 알고리즘을 구현하여 양돈의 표면적을 측정하여 이를 증체율로 표현할 수 있도록 구현하였다. 본 논문에서 제안된 방법을 통하여 손쉽게 양돈의 개체별 증체율을 측정할 수 있게 됨으로써 농장주의 요구에 부응할 수 있게 되었다. 향후에는 표면적 계산하는 알고리즘을 향상시켜 실제 측정치와 동일한 값이 구해질 수 있도록 개선 작업을 진행할 예정이다.

Evaluation of BTA1 and BTA5 QTL Regions for Growth and Carcass Traits in American and Korean Cattle

  • Kim, K.S.;Kim, S.W.;Raney, N.E.;Ernst, C.W.
    • Asian-Australasian Journal of Animal Sciences
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    • 제25권11호
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    • pp.1521-1528
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    • 2012
  • Previously identified QTL regions on BTA1 and BTA5 were investigated to validate the QTL regions and to identify candidate genes for growth and carcass traits in commercial cattle populations from the USA and Korea. Initially, a total of 8 polymorphic microsatellite (MS) markers in the BTA1 and 5 QTL regions were used for Chi-square tests to compare the frequencies of individual alleles between high and low phenotypic groups for the US (Michigan Cattleman's Association/Michigan State University; MCA/MSU) cattle. For a subsequent study, 24 candidate genes containing missense mutations and located within the QTL regions based on bovine genome sequence data were analyzed for genotyping in the two commercial cattle populations. Re-sequencing analyses confirmed 18 public missense SNPs and identified 9 new SNPs. Seventeen of these SNPs were used for genotyping of the MCA/MSU cattle (n = 98) and Korean native cattle (n = 323). On BTA1, UPK1B, HRG, and MAGEF1 polymorphisms residing between BM1312 and BMS4048 were significantly associated with growth and carcass traits in one or both of the MCA/MSU and Korean populations. On BTA5, ABCD2, IL22 and SNRPF polymorphisms residing between BL4 and BR2936 were associated with marbling and backfat traits in one or both of the MCA/MSU and Korean cattle populations. These results suggested that BTA 1 and 5 QTL regions may be segregating in both Korean Hanwoo and USA commercial cattle populations and DNA markers tested in this study may contribute to the identification of positional candidate genes for marker-assisted selection programs.

궤도기반 모델을 이용한 SPOT-5 HGR 입체영상의 3차원 위치결정 정확도 평가 (Accuracy Assessment of 3D Geo-positioning for SPOT-5 HRG Stereo Images Using Orbit-Attitude Model)

  • 위광재;김덕인;이하준;장용호
    • 한국측량학회지
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    • 제27권5호
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    • pp.529-534
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    • 2009
  • 위성영상은 제조사별로 지상해상력이 다르고, 위성의 특성마다 모델링하는 방법이 다르다. 또한 위성영상도 항공사진처럼 스테레오 영상 형태로 제공이 되지만, 스테레오로 입체시 했을 때에 발생하는 영상상의 시차나, 모델과 모델의 인접지역에서의 위치 오차에 대한 연구는 아직 미비한 상태이다. 최근에는 SPOT-5 위성영상을 이용한 공간정좌자료를 갱신하는 사례가 늘어나고 있다. SPOT-5 위성영상은 공간해상력이 2.5m로 1/5,000에서 1/20,000 수치지도 제작이 가능하다. 기존의 SPOT-5 위성영상의 정확도 해석은 대부분 단사진을 기반으로 자상기준점이나 모델링의 방법에 따른 정확도를 분석하는 연구가 이루어졌다. 따라서 본 연구에서는 SPOT-5 스테레오 위성영상에 대한 궤도기반모델기법을 적용하여 입체시를 통한 SPOT-5 위성영상의 정확도를 검증하였다. 궤도기반모델은 여러 가지 위성영상을 처리하는 센서모델 중 가장 정확도가 높은 모델링 기법으로 위성의 궤도력과 천문력을 이용하여 지상좌표를 정확하게 추출하는 방법이다. 이를 통하여 수치도하기 상에서 입체시를 수행하고 입체시를 통하여 지상기준점, 모델과 모델의 인접 정확도, 수치지도 제작 정확도를 분석하였다.

Experimental and Clinical Study of Korea Red Ginseng Treatment on Hypertension

  • Jin, En-Yuan;Jin, Ming;Wei, Yu-Lin;Huang, Lin-Hun;Yan, Xiao-Ping;Shi, Zai-Xiang;Huang, Li;Shen, De-Chu;Fu, Ren-Jie;Zhao, Tian-Yu;Nam, Ki-Yeul;Kumagai, Akira
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 1998년도 Advances in Ginseng Research - Proceedings of the 7th International Symposium on Ginseng -
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    • pp.190-198
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    • 1998
  • 1 . Experimental study Preventive effect of Korea Red Ginseng (KPG) on hypertensive retinal arteriolosis in rabbits was studied. The results as follows: Blood pressure: Hypertensive group (B) was obviously raised up in comparing with that in normal group(A) and in hypertension + KRG group(C). Ocular fundus:Changes in B group including the retinal arteriospasm, crossing arterioveous, exudation and edema. But C group showed lightly. Light microscope: HE stained vascular damage in retina including thickness hyalimisation, execdates and edema Electron microscope: The endothelial cells were arranged irregularly, different shape and showed cytoplasm loose and vacuole. Immunohistochemistry: Ginseng can regulating endothelin-1, angiotension-ll, endothelium grow factor expre,j,iion and secreation in retinal blood clrultion. 2. ClinicAl Study 66 of hypertensive patients (42 men, 23 women,48-68 years old)and 20 normal person (7 men, 13 women,47-68 years old) were administrated(p.0.) by HRG (3g per day for 6 weeks). The results showed that marked effective rate and total effective rate were 53cyo and 60.6alo respectively and no severe side effects were found. The above results suggest that Ginseng have a difinite hypotensive effect and a role of preventing hyperfine sloe arteriosclerosis.

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Chronic dietary ginseng extract administration ameliorates antioxidant and cholinergic systems in the brains of aged mice

  • Lee, Mi Ra;Ma, Jin Yeul;Sung, Chang Keun
    • Journal of Ginseng Research
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    • 제41권4호
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    • pp.615-619
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    • 2017
  • Background: Black ginseng has a more potent biological activity than non-steamed ginseng. We investigated the effects of long-term intake of dietary black ginseng extract (BG) on antioxidant activity in aged mice. We also compared the effects of BG on cognitive deficits with those of white ginseng extract (WG) and red ginseng extract (RG). Methods: Ten-month-old mice were fed an AIN-93G-based diet containing 10 g/kg (low dose, L) or 30 g/kg (high dose, H) WG powder, RG powder, or BG powder for 24 wk. We measured serum lipids, the activities of antioxidant enzymes, and malondialdehyde levels. Additionally, the protein expression levels of choline acetyltransferase and vesicular acetylcholine transporter, which are presynaptic cholinergic markers in the cortex and hippocampus of the brain, were measured by western blotting. Results: Triglyceride levels were reduced in all the extract-treated mice, except those in the LBG group. High-density lipoprotein cholesterol levels in the HBG group were higher than those in the control group. Total cholesterol levels were reduced in the LBG group. Additionally, glucose levels in the HBG group were significantly reduced by 41.2%. There were lower levels of malondialdehyde in the LBG group than in the control group. Furthermore, glutathione reductase activity increased in the HWG group and the HRG group. The protein expression levels of choline acetyltransferase and vesicular acetylcholine transporter significantly increased in all the ginseng-treated groups. Conclusion: The results suggest that supplementation with the tested ginseng extracts may suppress the cognitive decline associated with aging, via regulation of the cholinergic and antioxidant defense systems.

A Method of White Noise Reduction for Recognizing Cattle's Gulp Downing Sounds

  • Kwak, Ho-Young;Kim, Woo-Chan;Chang, Jin-Wook
    • 한국컴퓨터정보학회논문지
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    • 제24권11호
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    • pp.153-161
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    • 2019
  • 본 논문에서는 소의 목 넘김 소리를 이용하여 소의 사료 섭취량을 측정할 수 있도록 하는 방법을 제안하였다. 목 넘김 소리를 측정하기 위해 소의 목에 부착한 웨어러블 장치를 통해 녹음을 하게 되는데, 목장 사육환경에 따라 많은 소음이 함께 녹음되어진다. 이처럼 백색 잡음(white noise)이 섞여 들어간 원시 사운드 데이터를 스펙트럼화 하고, 필터를 이용한 신호 변환을 통하여 백색 잡음을 제거할 수 있는 방법을 제안하였다. 이를 통해 사료 섭취량을 측정할 수 있도록 하였다. 제안된 백색 소음 제거 방법을 통하여 소의 목 넘김 소리만을 추출하는 것이 가능하였고, 이를 통하여 소의 목 넘김 횟수 측정이 가능하였다. 본 논문에서 제안된 방법을 통하여 손쉽게 소의 사료섭취량을 측정할 수 있게 됨으로써 발정기 예측, 건강관리, 그리고 사료 관리 등이 효율적으로 이루어질 수 있게 되었다.