• Economic and Environmental Geology
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• v.27 no.3
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• pp.263-279
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• 1994

Paleomagnetic and rock-magnetic data of Cretaceous sedimentary and volcanic rocks from the Euiseong area indicate that the stable components of remanence are carried by single and pseudo-single domain magnetite, with the exception of the Shinyangdong Formation which has been remagnetized. The Hayang Group, except for the remagnetized Shinyangdong Formation, yields the mean characteristic direction of $D/I=22.5^{\circ}/57.2^{\circ}$ (${\alpha}_{95}=4.6^{\circ}$, N=14 sites) and the pole position is $72.0^{\circ}N$, $206.4^{\circ}E$ ($dp/dm=4.9^{\circ}/6.7^{\circ}$). The Yucheon Group shows two polarities and the mean characteristic direction of $D/I=351.2^{\circ}/60.5^{\circ}$ (${\alpha}_{95}=11.2^{\circ}$, N= 19 sites) and the pole position is $81.3^{\circ}N$, $79.0^{\circ}E$ ($dp/dm=13.0^{\circ}/17.0^{\circ}$). The mean directions of both the Hayang and the Yucheon Groups are supported by the McElhinny's fold test at the 99% confidence level and that of the Yucheon Group by a reversal test at the 95% confidence level. A magnetostratigraphic correlation between polarities of the study formations and the Geomagnetic Time Scale indicates that the Hayang Group can be correlated to the Cretaceous Long Normal Superchron (CLNS), and the Yucheon Group to the boundary between the CLNS and the Polarity Chron 33R or later boundaries between normal and reverse polarities. Comparison of the paleopoles from this study with those from the surrounding areas both within the Gyeongsang basin and in the northeastern Asia indicates that the study area was not undergone significant tectonic rotations with respect to the other parts of the Gyeongsang basin and that the Korean Peninsula was the part of the single terrane of the northeastern Asia at least since the CLNS. The Yucheon Group can be divided into four sub-groups based on the paleomagnetic data, suggesting that there were at least four times of volcanic activities in the study area.

• International Journal of Aeronautical and Space Sciences
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• v.1 no.1
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• pp.48-61
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• 2000

Korea Aerospace Research Institute (KARI) have gained experience with Helicopter Vibration Health Monitoring (VHM) System technology with the help of UK GKN-WHL. GKN-WHL have had many years of experience with the research and development of vibration analysis techniques to improve the health monitoring of helicopter transmissions. This activity was targeted at transmission rig testing at first, but the techniques have been progressively developed where they are now used as a part of integrated Health and Usage Monitoring (HUM) systems on many types of in-service and new helicopters. The technique development process has been considerably aided by an ever expanding database of transmission monitoring experience from both the rig testing and aircraft operations. This experience covers a wide range of failure types from naturally occurring faults to crack propagation studies and covering a wide range of transmission configurations. Primarily based on accelerometer signals GKN-WHL's vibration analysis methods have also been applied to a variety of other sensor types. The transition from an experimental environment to operational VHM systems has been a lengthy process, there being a need to demonstrate technique reliability as well as effectiveness to both regulatory (Airworthiness Authority) and commercial organizations. Another important feature of this process has been the development of close relationships with a number of VHM system hardware and software suppliers. Such an experienced GKN-WHL provides various raw vibration data which was acquired from transmission ground test rig and allow KARI to develop it's own analysis program. KARI made a program and then analyzed the data to coma pre with the results of GKN-WHL. The KARI's results both time domain signals and statistical values show comparable to GKN's.

• The Journal of the Korea Contents Association
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• v.5 no.3
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• pp.29-35
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• 2005

The task for chromosome analysis and diagnosis by experienced cytogenetists are being concerned as repetitive, time consuming job and expensive. For that reason, intelligent agent based on chromosome knowledge base using web has been developed to be able to analyze chromosomes and obtain necessary advises from the knowledge base instead of human experts. That is to say, the knowledge base of IF THEN production rule was implemented to a knowledge domain with normal and abnormal chromosomes, and then the inference results by the knowledge base could enter the inference data into the database. Experimental data were composed of normal chromosomes of 2,736 cases and abnormal chromosomes of 259 cases that have been obtained from GTG-banding metaphase peripheral blood and amniotic fluid samples. The completed intelligent agent for the chromosome knowledge base provides variously morphological information by analysis of normal or abnormal chromosomes also has the advantage of being able to consult with the user on the chromosome analysis and diagnosis.

• Journal of Korea Multimedia Society
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• v.21 no.8
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• pp.837-848
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• 2018

Monitoring technology of machining has a long history since unmanned machining was introduced. Despite the long history, many researchers have presented new approaches continuously in this area. Sound based machine fault diagnosis is the process consisting of detecting automatically the damages that affect the machines by analyzing the sounds they produce during their operating time. The collected sound is corrupted by the surrounding work environment. Therefore, the most important part of the diagnosis is to find hidden elements inside the data that can represent the error pattern. This paper presents a feature extraction methodology that combines various digital signal processing and pattern recognition methods for the analysis of the sounds produced by tools. The magnitude spectrum of the sound is extracted using the Fourier analysis and the band-pass filter is applied to further characterize the data. Statistical functions are also used as input to the nonlinear classifier for the final response. The results prove that the proposed feature extraction method accurately captures the hidden patterns of the sound generated by the tool, unlike the conventional features. Therefore, it is shown that the proposed method can be applied to a sound based automatic diagnosis system.

• Journal of Biomedical Engineering Research
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• v.10 no.3
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• pp.253-260
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• 1989

The time domain methods of estimating the attenuation coefficient are generally based on the analysis of statisical properties of the reflected echoes form an attenuating medium. Hence, it is often required to have a large number of data samples in order to obtain a statistically stable estimation result. In the attenuation estimation problem, this means that many different speckle patterns are required in the spatial resolution volume of an attenLlation image. In this paper, by using the fact that the speckle pattern Is sensitive to the point spread function of the ultrasound beam, we suggest a method to generate the statiscally uncorrelated or slightly correlated data samples in a given region by rotating a linear transducer and carrying out lateral scans for all rotating angles. This technique is applied to the entropy method for attenuation estimation proposed recently by the authors where the performance is verified by experiments using a tissue equivalent phantom.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.3
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• pp.35-47
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• 2004

Telematics and LBS is one of rapidly emerged technology domains. In order to efficiently construct them, moving object technology which manages huge volume of real-time location data is required. Especially, the query which obtains special sorts of information closely related to the detailed applications is required in order to effectively retrieve and analyze the location data for moving object in logistics domain. It has also complex query structure comparing to the conventional database query. The approach using the standard database query language, like SQL, can be considered as an effective alternative choice. In this paper, we not only propose a new query language, entitled as MOQL based on SQL, for the query processing of the vehicle monitoring and control in e-Logistics but also design and implement the query processor.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.6A
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• pp.465-473
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• 2005

In this paper, the reduction scheme of Interchannel Interference(ICI) caused by the phase noise in Orthogonal Frequency Division Multiplexing(OFDM) systems for archiving high data rates is proposed. The performance of conventional common phase error(CPE) compensation method is degraded by the phase noise with wide 3dB bandwidth in OFDM systems width a higher-order constellation. After estimating dominant ICI coefficients using pilot subcarriers and data subcarriers adjacent to pilot subcarriers, the proposed scheme compensates OFDM signals distorted by the phase noise using estimated coefficients in the time or frequency domain. Also, in order to determine the length of dominant ICI coefficients effectively, the estimation method of the 3dB bandwidth of the phase noise is proposed. The proposed phase noise reduction method is shown to improve the Bit Error Ratio(BER) performance compared with the conventional CPE compensation.

• Convergence Security Journal
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• v.16 no.5
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• pp.73-79
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• 2016

EPG (Electronic Program Guide), which shows the title, broadcasting time, genre, parental rating of a program, is recognized as one of the most successful data service by viewers and broadcasting stations, who want an improved TV watching experience and a more fruitful profit model, respectively. In the circumstance, the request for the development or renewal of EPG frequently occurs and so the developers are looking for ways to improve the efficiency of the EPG development. This paper addresses the need of the developers by devising an EPG feature model based on FODA (Feature-Oriented Domain Analysis) and the testcases of each feature of the model. By utilizing the EPG feature model and the testcases, the tasks of requirement analysing and testcase designing, which are major tasks of the EPG development process, can be improved.

• Journal of the Korean Geotechnical Society
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• v.21 no.6
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• pp.147-154
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• 2005

This study deals with the calibration of low-frequency water content reflectometer for measuring the volumetric water content of soils in landfill final cover layer, and the validity of calibrations was evaluated by electrical conductivity and index properties of the soils. Linear calibrations concerning volumetric water content to WCR period provided good agreement with the data. Analysis of the calibration data indicates that the slope of the calibration decreases as the electrical conductivity of the soil increases. Lower slopes correspond to soils with greater clay content, organic content, liquid limit, and plasticity index, which typically have higher electrical conductivity. It could be well explained that WCR can operate in a lower frequency range.

• Journal of the Korea Society for Simulation
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• v.15 no.4
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• pp.11-19
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• 2006

With the emergence of pervasive computing, personalization becomes an important issue to provide with users customized services, anywhere and anytime in their specific environment. Many researches have shown the possibilities of personalization by acquiring and processing sensor information around users. However, personalization remains still at its infancy, since most researches have failed to consider various contexts comprehensively besides sensor data, and just developed tailored services for a specific application domain. In this work, we propose a simulation-based CAS (context Aware Web Services) development methodology. Our methodology considers various contexts on users (eg. current location), web services (eg. response time), devices (eg. availability) and environment (eg. sensor data) all together by simulating them on the fly for personalized and adaptable services.