• Journal of Astronomy and Space Sciences
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• v.23 no.3
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• pp.259-268
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• 2006

The use of GPS receiver at outer space becomes common in low earth orbit. Recently most of satellites use GPS receiver as navigation solution for finding satellite position. However, the accuracy of navigation solution acquiring directly from GPS receiver is not enough in satellite application such as map generation. Post-processing concepts such as Precise Orbit Determination (POD) are recently applied to satellite data processing to improve satellite position accuracy. The POD uses raw measurement data instead of navigation solution of GPS receiver. The performance of raw measurement data depends on raw measurement data accuracy and tracking loop algorithm of GPS receiver. In this paper, a method for evaluating performance of raw measurement data is suggested. Test environment and procedure of the low earth orbit satellite acquiring for navigation solution of GPS receiver and navigation solution of POD are described. In addition, accuracy on navigation solution of GPS receiver, raw measurement data, and navigation solution of POD are analyzed. The proposed method can be applicable to general low earth orbit satellite.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.4
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• pp.547-554
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• 2011

In small-scale water systems, the measurement of quality of raw water in running water is generally implemented when the quality of water is stable and frequency of measurement is low. However, units such as water temperature and pH, which are easily monitored, are frequently measured. In establishing an improvement plan for a water treatment system, the range of concentration of the target material present in the raw water of the running water provides relevant information. If the concentration of target material can be specified by the quality of water of data items that are measured daily, inverse estimation of the range of concentration is possible as well. In this paper, we took note of manganese in the raw water from Ogasawara-mura, Tokyo, and estimated the manganese concentration in the raw water of the running water for the past five years. Based on the results obtained, we have proposed a manganese removal system, considering the current situation and geographical conditions of Ogasawara-mura.

• Journal of Sensor Science and Technology
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• v.31 no.2
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• pp.96-101
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• 2022

As the elderly population gradually increases, the risk of fatal fall accidents among the elderly is increasing. One way to cope with a fall accident is to determine the fall direction before impact using a wearable inertial measurement unit (IMU). In this context, a previous study proposed a method of classifying fall directions using a support vector machine with sensor velocity, acceleration, and tilt angle as input parameters. However, in this method, the IMU signals are processed through several processes, including a Kalman filter and the integration of acceleration, which involves a large amount of computation and error factors. Therefore, this paper proposes a machine learning-based method that classifies the fall direction before impact using IMU raw signals rather than processed data. In this study, we investigated the effects of the following two factors on the classification performance: (1) the usage of processed/raw signals and (2) the selection of machine learning techniques. First, as a result of comparing the processed/raw signals, the difference in sensitivities between the two methods was within 5%, indicating an equivalent level of classification performance. Second, as a result of comparing six machine learning techniques, K-nearest neighbor and naive Bayes exhibited excellent performance with a sensitivity of 86.0% and 84.1%, respectively.

• Corrosion Science and Technology
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• v.12 no.3
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• pp.142-148
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• 2013

Safety is a major concern in Nuclear Power Plants (NPPs). Piping systems in NPPs are very complex and composed of many components such as tees, elbows, expanders and straight pipes. The high pressure and high temperature water flows inside piping components. As high speed water flows inside piping, the pipe wall thinning occurs in various reasons such as FAC (Flow Accelerated Corrosion), LDIE (Liquid Droplet Impingement Erosion) and Flashing. To inspect the wall thinning phenomenon and protect the piping from damages, piping components are checked by UT measurement in every overhaul. During every overhaul, approximately 200~300 components (40,000~60,000 UT data) are examined in NPPs. There are some methods from EPRI for evaluating wear rate of components. However, only few studies have been conducted to find out the raw data reliability for the wear rate evaluation. Securing the reliable raw data is the key factor for a reasonable evaluation. This paper suggests the reliability analysis method for the repeatedly measured data for wear rate evaluation.

• Korean Chemical Engineering Research
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• v.47 no.5
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• pp.599-607
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• 2009

This study was conducted to derive the five correlations which could predict specific gravity(or heating value), compression factor, density, etc., if we know heating value or specific gravity only. To make a sufficient number of raw data for regression, SGERG EOS was modified into equation of heating value. Based on these raw data, five correlations were obtained and the uncertainties of the correlations were evaluated. The results showed that the uncertainties were near 0.1% in most conditions of natural gas and so the correlations could be used in natural gas industry and academic fields.

• Journal of Korean Medicine for Obesity Research
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• v.12 no.1
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• pp.33-47
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• 2012

Objectives This study was designed to investigate the effects of fermented soybean upon anti-inflammation, cytotoxicity, antioxidant and intestinal mucous membrane permeability by measuring the cell viability, NO (nitric oxide) production, DPPH, Polyphenol, HRP and TEER in cells like Raw 264.7 and HCT 116 using fermented soybean. Methods Raw 264.7 cell and HCT 166 cell were used in this study. And fermented soybean powders were used for the experimental group and soybean powders for the control group. There was inflammation response upon using lipopolysaccharide(LPS). Fermented soybean powders and soybean powders were in a respectively different dose added to the cells with LPS. MTT assay, NO, DPPH and Polyphenol measurement, TEER, HRP were conducted for each cell. The results of this study were presented in mean and standard deviation. Results 1. In Raw 254.7 cells added with $100{\mu}l/ml$ unfermented soybean powders, 104.95% higher than 62.59% was measured. In Raw 254.7 cells added with $100{\mu}l/ml$ fermented soybean powders, there was 74.90% measured higher than 62.59%, which was a significant result. 2. By a gradual increase of unfermented soybean powders like $0.1{\mu}l/ml$, $1.0{\mu}l/ml$, $10{\mu}l/ml$, $100{\mu}l/ml$, the measured NO were also gradually decreased $53.12{\mu}M$, $47.57{\mu}M$, $37.02{\mu}M$, $28.16{\mu}M$. In case of cells added with fermented soybean powders, $43.95{\mu}M$ NO was measured in $0.1{\mu}l/ml$ which is significant, and in other cases, mostly measured over$ 56.72{\mu}M$. 3. It was inferred that fermented soybean powders have anti-inflammatory effects of maintaining intestinal mucous membrane permeability because the measured values of cells in both groups were all higher than $133.62{\Omega}$ measured of cells added with only LPS. And measured values of cells in both groups were all lower than 2.26 measured of cells added with only LPS. 4. In case of experiment DPPH and polyphenol measurement, fermented group was all higher than unfermented group. Conclusion From the results of conducting MTT assay, NO measurement, and TEER, HRP by using cells Raw 264.7 and HCT-116, even though there was no significance in the correlation between cytotoxicity, anti-inflammatory effects, both unfermented soybean powders and fermented soybean powders were shown to have intestinal mucous membrane permeability improvement effects. This effects could be applicable for autoimmune diseases, chronic inflammatory diseases and so additional studies are expected in the future. From the results of conducting DPPH, Polyphenol measurement, Fermented soybean may be useful as potential antioxidant.

• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.822-825
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• 1999

This paper compares two methods of GPS/INS integration ; tightly-coupled integration ana loosely-coupled integration. In the tightly -coupled method an integrated Kalman filter is designed to process raw GPS measurement data for state update and INS data for propagation. The loosely-coupled integration method uses the solution outputs from a stand-alone GPS receiver for update. The loosely-coupled method is simpler and can readily be applied to off-the-self receivers and sensors while the tightly-coupled integration requires access to raw measurement mechanism of the receiver. Simulation result show that the tightly-coupled integration system exhibits better performance and robustness than loosely-coupled integration method.

• Design & Manufacturing
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• v.17 no.2
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• pp.33-41
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• 2023

Metal raw materials and chemical additives, which are raw materials for secondary batteries, are pulverized by the high-speed rotation of the Grinding Disc of the Classifier Separator Mill (CSM). Grinding discs are required to withstand abrasion, corrosion, high-speed rotational force and impact. In order to analyze the stability of domestic and foreign grinding discs, quality tests including surface roughness, surface lubrication, surface state measurement, and surface 3D shape measurement were analyzed. When producing developed products, it shows that excellent products can be produced.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.45-49
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• 2004

The Navstar Global Positioning System(GPS) is an advanced navigation satelite system for determination of position, velocity and time. It can provide three-dimensional positioning on a global basis, independent of weather, 24 hours per day. Test results show that the carrier phase and pseudorange corrections are suitable for a kinematic GPS system. Using these corrections are more effective than using raw GPS data, since fewer bits are required for transmission Additionally, the number of computation required at the rover is reduced when corrections, rather than raw measurement are transmitted

• Proceedings of the Korean Fiber Society Conference
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• 1989.06a
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• pp.91-91
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• 1989