• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.475-478
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• 2006

본 논문에서는 소형 무인항공기의 정확한 위치, 속도, 자세 정보를 제공하기 위해 저급의 MEMS IMU를 이용한 항법 시스템을 제안한다. 제안하는 시스템은 비행체의 직선운동과 회전운동을 측정할 수 있는 관성측정기와 위성신호를 수신하여 항체의 위치, 속도 정보를 제공하는 GPS 수신기, 지구 자기장 정보를 이용하여 방향각 정보를 제공하는 지자기 센서들로 구성되었다. SDINS와 약결합 방식의 칼만필터를 이용한 항법 시스템은 초기정렬 알고리즘과 센서 오차 보상 알고리즘, 자력계 보상 알고리즘 및 복합항법 알고리즘으로 나뉘며, 설계된 항법 알고리즘들은 시뮬레이션과 차량 실험을 통해서 성능을 분석하였다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.55-59
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• 2000

A specific and sensitive sandwich enzyme-immunoassay (EIA) using Avidin-Biotin complex was developed for the measurement of GTH II levels in pituitary content and pituitary cell culture medium of the rainbow trout-(Oncorhpchus mykiss). Biotin-salmon GTH II rabbit IgG (sefondary antibody) wai purified by a protein A sepharose affinity chromatography column and that was biotinylated by using Biotin-N-hydroxysuccinimide ofter (BNHS). Non-biotin salmon GTH II rabbit IgG (first antibody) was obtained only through a protein A sepharose affinity chromatography column. The assay was performed by the so-called 'sandwich' method using a microtiter plate, A dose-response curve was obtained between $0.12 to 125 ng/ml$ of salmon GTH II. The displacement curves for pituitary extraction and pituitary cell culture medium of testosterone-treated rainbow trout were Parallel to the standard curie. The intra-assay and inter-assay coefficients of variation (CV) were $8.2{\%} (N=5) and 12.5{\%} (N=6)$, respectively, This assay system was used to measure the amount of GTH II that accumulated in the culture medium of dispersed pituitary cells in testosterone-treated immature rainbow trout, The accumulation was increased with the amount or salmon gonadotropin-releasing hormone. GTH II values determined by the present method were well correlated with those determined by radioimmunoassay. As a result, this assay system was found to be suitable for the measurement of GTH II for pituitary extraction and pituitary culture medium in many salmonid fishes.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.4
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• pp.285-293
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• 2020

In this paper, to improve Synthetic Aperture Radar (SAR) image quality, the effect of time synchronization error in the EGI/IMU (Embedded GPS/INS, Inertial Measurement Unit) integrated system is analyzed and state augmentation is applied to compensate it. EGI/IMU integrated system is widely used as a SAR motion measurement algorithm, which consists of EGI mounted to obtain the trajectory and IMU mounted on the SAR antenna. In an EGI/IMU integrated system, a time synchronization error occurs when the clocks of the sensors are not synchronized. Analysis of the effect of time synchronization error on navigation solutions and SAR images confirmed that the time synchronization error deteriorates SAR image quality. The state augmentation is applied to compensate for this and as a result, the SAR image quality does not decrease. In addition, by analyzing the performance and the observability of the time synchronization error according to the maneuver, it was confirmed that the time-variant maneuver such as rotational motion is necessary to estimate the time synchronization error adequately. In order to reduce the influence of the time synchronization error on the SAR image, the time synchronization error must be compensated by performing maneuver changing over time such as a rotation before SAR operation.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.6
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• pp.481-487
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• 2013

In GPS(Global Positioning System)/INS(Inertial Navigation System) integrated navigation systems, GPS antennas and an inertial measurement units are usually installed outside and inside of the vehicle, respectively. By the difference of installed locations, performance of GPS/INS integrated navigation systems is affected by lever arm errors. For more accurate navigation, lever arm errors need to be compensated correctly since it directly affects the accuracy of navigation states. This paper proposes an effective lever arm error compensation method that utilizes velocity measurements of GPS and INS. By an experiment, feasibility of the proposed algorithm is verified. It is also shown that lever arm compensation is especially important when vehicles are experiencing rotational movements.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.5
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• pp.531-537
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• 2010

Real-time Aerial Monitoring System performs the rapid mapping in an emergency situation so that the geoinformation could be constructed in near real time. In this system, the position and attitude information from GPS/INS integration algorithm is used to perform the aerial triangulation(AT) without GCPs. Therefore, if we obtain Exterior Orientation(EO) estimates from AT sequentially, EO are used as the measurements in the Kalman filter. In this study, we simulate the GPS/IMS/Image data for an UAV-based aerial monitoring system and compare the GPS/INS/AT with and without from AT. Comparative analysis showed that result from the GPS/INS/AT with EO update is more accurate than without the update. However, when the vehicle turns, the position error significantly increases which need more analysis in the future.

• Tuberculosis and Respiratory Diseases
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• v.53 no.5
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• pp.497-509
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• 2002

Background : The mechanisms through which cellular activation results in intracellular mycobacterial killing is only partially understood. However, in vitro studies of human immunity to Mycobacterium tuberculosis have been largely modeled on the work reported by Crowle, which is complicated by several factors. The whole blood culture is simple and allows the simultaneous analysis of the relationship between bacterial killing and the effect of effector cells and humoral factors. In this study, we attempted to determine the extent to which M. tuberculosis is killed in a human whole blood culture and to explore the role of the host and microbial factor in this process. Methods : The PPD positive subject were compared to the umbilical cord blood and patients with tuberculosis, diabetes and lung cancer. The culture is performed using heparinized whole blood diluted with a culture medium and infected with a low number of M. avium or M. tuberculosis $H_{37}Ra$ for 4 days by rotating the culture in a $37^{\circ}C$, 5% $CO_2$ incubator. In some experiments, methlprednisolone- or pentoxifyline were used to inhibit the immune response. To assess the role of the T-cell subsets, CD4+, CD8+ T-cells or both were removed from the blood using magnetic beads. The ${\Delta}$ log killing ratio was defined using a CFU assay as the difference in the log number of viable organisms in the completed culture compared to the inoculum. Results : 1. A trend was noted toward the improved killing of mycobacteria in PPD+ subjects comparing to the umbilical cord blood but there was no specific difference in the patients with tuberculosis, diabetes and lung cancer. 2. Methylprednisolone and pentoxifyline adversely affected the killing in the PPD+ subjects umbilical cord blood and patients with tuberculosis. 3. The deletion of CD4+ or CD8+ T-lymphocytes adversely affected the killing of M. avium and M. tuberculosis $H_{37}Ra$ by PPD+ subjects. Deletion of both cell types had an additive effect, particularly in M. tuberculosis $H_{37}Ra$. 4. A significantly improved mycobacterial killing was noted after chemotherapy in patients with tuberculosis and the ${\Delta}$ logKR continuously decreased in a 3 and 4 days of whole blood culture. Conclusion : The in vitro bactericidal assay by human whole blood culture model was settled using a CFU assay. However, the host immunity to M. tuberculosis was not apparent in the human whole blood culture bactericidal assay, and patients with tuberculosis showed markedly improved bacterial killing after anti-tuberculous chemotherapy compared to before. The simplicity of a whole blood culture facilitates its inclusion in a clinical trial and it may have a potential role as a surrogate marker in a TB vaccine trial.