• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.285-289
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• 2006

In this paper, a design and implementation of GPS/Galileo software receiver is given. As a GPS receiver, it is able to perform every function of receiver such as acquisition, code and carrier tracking, navigation bit extraction, navigation data decoding, pseudorange calculations, and position calculations. A method to acquire and track the Galileo BOC(1,1) signal is also required because the correlation of BOC(1,1) signal has multiple peaks different from that of GPS signal. Therefore, a method to detect the main-peak in correlation function of BOC signal is required to avoid false acquisition. In this paper, very-early, very late correlation is implemented to track the correct main peak. The performance of implemented GPS/Galileo software receiver with BOC(1,1) signal tracking feature is evaluated with GPS/Galileo IF signal generator.

• Journal of Ocean Engineering and Technology
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• v.33 no.5
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• pp.421-426
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• 2019

The directivity of an underwater sound source should be measured in an acoustically open field such as a calm sea or lake, or an anechoic water tank facility. However, technical difficulties arise when practically implementing this in open fields. Signal processing-based techniques such as a sound intensity method and near-field acoustic holography have been adopted to overcome the problem, but these are inefficient in terms of acquisition and maintenance costs. This study established a simple directivity estimation technique with data acquisition, filtering, and analysis tools. A numerical simulation based on an acoustic radiosity method showed that the technique is practicable for sound source directivity estimation in a diffused reverberant acoustic field like a reverberant water tank.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.906-909
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• 2000

To improve dimension accuracy and make very small parts are one of the major purpose on the electrochemical micromachining. This paper introduce a small machine tool by using the point electrode. That has a data acquisition system for gathering applied electric condition between the gap. Point electrode on this system was made by this method as well. It was found that variable phenomena occurred through the acquired V-I curve on the process.

• Journal of electromagnetic engineering and science
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• v.6 no.4
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• pp.229-234
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• 2006

This paper presents an advanced method of simulation for EM(electromagnetic) environment that affects on mobile receivers. A new calibration algorithm in the process of simulation is introduced. With a proposed calibration method, the time required for simulation is reduced and this makes it possible to simulate a near-real time EM environment in a shielded anechoic chamber. EM environment data acquisition and logging techniques with GPS for simulation were developed.

• Journal of Biomedical Engineering Research
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• v.41 no.2
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• pp.107-119
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• 2020

The deep neural networks (DNN) that can replicate the behavior of the human expert who recognizes the characteristics of ECG waveform have been developed and studied to analyze ECG. However, although the existing DNNs can not provide the explanations for their decisions, those trials have attempted to determine whether patients have certain diseases or not and those decisions could not be accepted because of the absence of relating theoretical basis. In addition, these DNNs required a lot of training data to obtain sufficient accuracy in spite of the difficulty in the acquisition of relating clinical data. In this study, a small-sized continuous data processing DNN (C-DNN) was suggested to determine the simple characteristics of ECG wave that were not required additional explanations about its decisions and the C-DNN can be easily trained with small training data. Although it can analyze small input data that was selected in narrow region on whole ECG, it can continuously scan all ECG data and find important points such as start and end points of P, QRS and T waves within a short time. The star and end points of ECG waves determined by the C-DNNs were compared with the results performed by human experts to estimate the accuracies of the C-DNNs. The C-DNN has 150 inputs, 51 outputs, two hidden layers and one output layer. To find the start and end points, two C-DNNs were trained through deep learning technology and applied to a parameter acquisition algorithms. 12 lead ECG data measured in four patients and obtained through PhysioNet was processed to make training data by human experts. The accuracy of the C-DNNs were evaluated with extra data that were not used at deep learning by comparing the results between C-DNNs and human experts. The averages of the time differences between the C-DNNs and experts were 0.1 msec and 13.5 msec respectively and those standard deviations were 17.6 msec and 15.7 msec. The final step combining the results of C-DNN through the waveforms of 12 leads was successfully determined all 33 waves without error that the time differences of human experts decision were over 20 msec. The reliable decision of the ECG wave's start and end points benefits the acquisition of accurate ECG parameters such as the wave lengths, amplitudes and intervals of P, QRS and T waves.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.3
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• pp.55-62
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• 2010

Currently, cost estimation is very important to the government acquisition programs to support decisions about funding and to evaluate resource requirement as key decision points. Parametric cost estimating models have been used extensively to obtain appropriate cost estimates in early acquisition phase. However, they have many restrictions to ensure the cost estimating result in Korean defense environment because they are developed in the U.S.A. environment. In order to obtain a good R&D cost estimate, developing our own CERs (Cost Estimation Relationships) using historical R&D data is essential. Nevertheless, there has been little research to develop our own CERs. In this research, we established a CER development process and found some cost drivers in the historical movement weapon system R&D data. The R&D CER is developed using the PCR(Principle Component Regression) method to remove multicollinearity among data and to overcome the restriction of the insufficient number of sample. At least, this research is meaningful as a first attempt in terms of defining the CER development process and obtaining our own R&D CER based on the historical data in Korean weapon system R&D environment.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.6
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• pp.569-578
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• 2016

With the recent advancement of surveying and technology, the spatial data acquisition rates and precision have been improved continually. As the updates of spatial data are rapid, and the size of data increases in line with the advancing technology, the LOD (Level of Detail) algorithm has been adopted to process data expressions in real time in a streaming format with spatial data divided precisely into separate steps. The existing GRID analysis utilizes the single DEM, as it is, in examining and analyzing all data outside the analysis area as well, which results in extending the analysis time in proportion to the quantity of data. Hence, this study suggests a method to reduce analysis time and data throughput by acquiring and analyzing DEM data necessary for GRID analysis in real time based on the area of analysis and the level of precision, specifically for streaming DEM data, which is utilized mostly for 3D geographic information service.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.244-249
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• 1993

This paper proposes a method of automatic function test for parts mounted Printed Circuit Board. For this purpose, we designed a Data Acquisition Equipment, PC interface card and inspection software. The experiment was done for the coffee vending machine and its result was good.

• Journal of the korean Society of Automotive Engineers
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• v.9 no.5
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• pp.6-18
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• 1987

Owing to remarkable development in automotive industry, vehicle performance comes close to perfection and guarantee of stability is getting emphasized in accordance with high speed trend in vehicle. In recent years, the utilization of automatic test method for research and development of automotive brake system is being propelled actively, which pursue whole automatic control from simple measurement to data acquisition. The main subject of this paper is to make a brief explanation on Micro computer controlled Automatic Test Method for Automotive Brake System which makes it possible to test with high accuracy and speed.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.1
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• pp.111-122
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• 2018

Using OAuth protocol, third-party applications on the Android operating system use user's credentials or access tokens that have access authority on user's resources to gain user's account and personal information from account information providers. These credentials and token information are stored in the device by the OAuth data management method provided by the Android operating system. If this information is leaked, the attacker can use the leaked credential and token data to get user's personal data without login. This feature enables the digital forensic investigator to collect data directly from the remote server of the services used by the target of investigation in terms of collecting evidence data. Evidence data collected at a remote location can be a basis for secondary warranties and provide evidence which can be very important evidence when an attacker attempts to destroy evidence, such as the removal of an application from an Android device. In this paper, we analyze the management status of OAuth tokens in various Android operating system and device environment, and show how to collect data of various third party applications using it. This paper introduces a method of expanding the scope of data acquisition by collecting remote data of the services used by the subject of investigation from the viewpoint of digital forensics.