• The Journal of the Acoustical Society of Korea
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• v.41 no.2
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• pp.199-209
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• 2022

Typical anomaly detection algorithms are trained by using prior data. Thus the batch learning based algorithms cause inevitable performance degradation when characteristics of newly incoming normal data change over time. We propose an online anomaly detection algorithm which can consider the gradual characteristic changes of incoming normal data. The proposed algorithm based on one-class classification model includes both offline and online learning procedures. In offline learning procedure, the algorithm learns the prior data to be close to centroid of the latent space and then updates the centroid of the latent space incrementally by new incoming data. In the online learning, the algorithm continues learning by using the updated centroid. Through experiments using public underwater acoustic data, the proposed online anomaly detection algorithm takes only approximately 2 % additional learning time for the incremental centroid update and learning. Nevertheless, the proposed algorithm shows 19.10 % improvement in Area Under the receiver operating characteristic Curve (AUC) performance compared to the offline learning model when new incoming normal data comes.

• Journal of Microbiology and Biotechnology
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• v.33 no.6
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• pp.840-847
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• 2023

Korean ginseng (Panax ginseng C. A. Meyer), a member of the Araliaceae family, is known as a traditional medicinal plant to have a wide range of health properties. Polysaccharides constitute a major component of Korean ginseng, and its berries exhibit immune-modulating properties. The purpose of this study was to investigate the immune effects of crude polysaccharide (GBPC) extracted from Korean ginseng berry on peritoneal macrophages in mice with cyclophosphamide (CY)- induced immunosuppression. BALB/c mice were divided into eight groups: normal control, normal control + CY, levamisole + CY, ginseng + CY, and four concentrations of 50, 100, 250, and 500 mg/kg BW/day of GBPC + CY. Mice were orally administered with samples for 10 days. Immunosuppression was established by treating mice with CY (80 mg/kg BW/day) through intraperitoneal injection on days 4 to 6. The immune function of peritoneal macrophages was then evaluated. Oral administration of 500 mg/kg BW/day GBPC resulted in proliferation, NO production, and phagocytosis at 100%, 88%, and 91%, respectively, close to the levels of the normal group (100%) of peritoneal macrophages. In CY-treated mice, GBPC of 50-500 mg/kg BW/day also dose-dependently stimulated the proliferation, NO production, and phagocytosis at 56-100%, 47-88%, and 53-91%, respectively, with expression levels of immune-associated genes, such as iNOS, COX-2, IL-1β, IL-6, and TNF-α, of about 0.32 to 2.87-fold, compared to those in the CY group. GBPC could be a potential immunomodulatory material to control peritoneal macrophages under an immunosuppressive condition.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.470-473
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• 2000

Because of the continuous growth of energy consumption, and also the tendency to site power lines and pipelines along the same routes, the close proximity of high voltage structures and metallic pipelines has become more and more frequent. Moreover, normal steady state and fault currents become higher as electric networks increase in size and power. Therefore, there has been and still is a growing concern (safety of people marking contact with pipeline, risk of damage to the pipeline coating, the metal and equipment connected to pipeline. especially cathodic protection system) about possible hazards resulting from the influence of high voltage power system on metallic structures(gas pipeline, oil pipeline and water pipeline etc.). Therefore, we analyze the interference problems when the gas pipeline is buried with power cable in the same submarine tunnel. This paper present the results of the study about interference mechanism, AC corrosion, limitation of safety voltage and analysis of indiction voltage.

• International Journal of Precision Engineering and Manufacturing
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• v.6 no.3
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• pp.24-28
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• 2005

Stress state of chip formation zone is one of the main problems in metal cutting mechanics. In two-dimensional case this process is usually considered as consistent shears of work material along one of several shear surfaces, separating chip from workpiece. These shear planes are assumed to be trajectories of maximum shear stress forming corresponding slip-line field. This paper suggests a new approach to the constriction of slip-line field, which implies uniform compression in chip formation zone. Based on the given model it has been found that imaginary shear line in orthogonal cutting is close to the trajectory of maximum normal stress and the problem about its determination has been considered as well. It has been shown that there is a second central slip-line field inside chip, which corresponds well to experimental data about stress distribution on tool rake face and tool-chip contact length. The suggested model would be useful in understanding mechanistic problems in machining.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.12
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• pp.1726-1731
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• 2014

This paper shows the developed new lightning arrester LCM (Leakage Current Measuring device) which is important element of GIS (Gas Insulated Switchgear) Preventive & Diagnostic system and verify its performance though strengthened test standards. The existing lightning arrester LCM was modified to solve measuring errors which happened frequently. At first, we explained the principle of measuring leakage current. Through analyzing some problems which the existing LCM have. we got some improvable items. For the performance verification of the improved LCM, we manufactured prototype LCM which is applied some improvable items such as improving LCM circuit, adding protection circuit, optimizing inner structure of LCM and changing ground design. After then we carried out the performance test. Accredited testing laboratory carried out the performance verification test according to performance test criteria and procedure of reliability test standards, IEC-60225, 61000 and 60068 etc. We confirmed the test results which correspond with the performance test criteria. Also, we confirmed the performance of the improved LCM installed & being operated at G Substation through the immunity test against the normal noise and open/close surge etc.

• Korean Institute of Interior Design Journal
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• v.21 no.1
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• pp.68-77
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• 2012

Appreciating the aspect of modem architecture requires not only the comprehension of the nature of design and architects' ways of thinking and expression but also observers' views on buildings and their perceptive/cognitive stages. This calls for an in-depth study on the "system of phenomenological perceptions" that works as a new architectural experience system. The system of phenomenological perceptions makes it possible to specify the individual process of understanding architecture, that is, hands-on experiences, participations, feelings, perceptions, and cognition. The value of user experience and cognition has been emphasized by philosophical and aesthetical concepts as well. Therefore, in order to better appreciate the modern architecture, this study suggests theoretical consideration to "orientation and event" that are crucial elements in understanding a phenomenological view and materializing actual space formation. This offers the cognitive system with which we analyze modem architecture and comprehensive expressional methods. In other words, this study contemplates the system of phenomenological perceptions from an existential spatial perspective by structurizing the system of the orientation and the event in order to segmentalize users' current locations, potential directions, the relations with spaces, continual vie'wpoints as well as buildings' functions and interior and exterior division. The system of phenomenological perceptions helps understand and systemize modern architecture through a system based on relations between sensation, perception, cognition, sensitivity, and rationality. This creates a new cognitive system employing the concept of the orientation and the event, which is different from a normal cognitive system basing on the sense of vision. When observers appreciate space, they tend to relate the space to a certain event and to remember their experiences in it. During the process, they draw borders of the space in which the event takes place and give shape to their experiences including actions, movements, cognition and sensation. The process leads to the formation of "placeness," and here, the concept of the orientation comes in as the location and the center of the placeness. This study proves that a determined orientation coupled with individual experience and events settles the place ness; detailed elements in the cognitive system have close relations with one another; the orientation, actions, events, and places are the factors that materialize observers' architectural experience.

• Korean Institute of Interior Design Journal
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• no.12
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• pp.40-49
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• 1997

What's the direction of INTERIOR ARCHITECTURAL DESIGN in 21 Century High Tech\ulcorner The purpose of this research is to show not only practical use of Computer Graphic(CG) as simple tool function, but offering conversation with computer and other ways of method. When we consider poor CG market, investment on the research of VR(Virtual Reality) is the most urgent. The investment on VR will solve various problems. Firstly. It will solve the problems drived from Interior design process by making spatial images like reality. Secondly, It will solve high wages and financial difficulties caused by raise cost funds. Thirdly, It prevents in a road from foreign company that will bring enormous program, caused by opening the domestic market. Also, It help interior designer check in advance the problems in constructure through showing him a supposed imagination including the system and location of equipments. But it is reality that even ordinary American can't offer VR(Virtual Reality) System. We should have noted that it is normal to spend 10 billion won for such presentation as Model House in the large corporation. We must acknowledge that it is such a waist of money nationally. Therefore, investment on CG & VR System is essential in order to save cost more effective presentation & interior design. We will see great result within a year. As we can see, there is huge area we have make develop. One of them is specific technical plan on VR System and study of flow chart. We close with simple methodological way to use VR System and will study Computer System. Which is fitting to CG that we have to solve the link of hardware and software on VR System\ulcorner We know from the cases in other countries that continuous research on this subject has great value for Interior Architectural Design and its effective use. When we try hard not only for methodological use but practical use, the purpose of CG and VR System will be a factor to contribute on this subject for better Interior design & presentation.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.9 no.1
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• pp.15-19
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• 2013

The auxiliary feedwater is an important to remove the heat from the reactor core when the main feedwater system is unavailable. In most initiating events in Probabilistic Safety Assessment(PSA), the operaton of this system is required to mitigate the accidents. For one of domestic nuclear power plants, a design change of a turbine-driven auxiliary feedwater pump(TD-AFWP), pipe, and valves in the auxiliary system is implemented due to the aging related deterioration by long time operation. This change includes the replacement of the TD-AFWP, the relocation of some valves for improving the system availability, a new cross-tie line, and the installation of manual valves for maintenance. The design modification affects the PSA because the system is critical to mitigate the accidents. In this paper, the safety effect of the change of the auxiliary feedwater system is assessed with regard to the PSA view point. The results demonstrate that this change can supply the auxiliary feedwater from the TD-AFWP in the accident with the motor-driven auxiliary feedwater pump(MD-AFWP) unavailable due to test or maintenance. In addition, the change of MOV's normal position from "close" to "open" can deliver the water to steam generator in the loss of offsite power(LOOP) event. Therefore, it is confirmed that the design change of the auxiliary feedwater system reduces the total core damage frequency(CDF).

• Journal of Internet Computing and Services
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• v.2 no.4
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• pp.41-53
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• 2001

Multi-distributed web cluster model built for high availability E-Business model exposes internal system nodes on its structural characteristics and has a potential that normal job performance is impossible due to the intentional prevention and attack by an illegal third party. Therefore, the security system which protects the structured system nodes and can correspond to the outflow of information from illegal users and unfair service requirements effectively is needed. Therefore the suggested distributed invasion detection system is the technology which detects the illegal requirement or resource access of system node distributed on open network through organic control between SC-Agents based on the shared memory of SC-Server. Distributed invasion detection system performs the examination of job requirement packet using Detection Agent primarily for detecting illegal invasion, observes the job process through monitoring agent when job is progressed and then judges the invasion through close cooperative works with other system nodes when there is access or demand of resource not permitted.

• Ecology and Resilient Infrastructure
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• v.10 no.4
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• pp.143-160
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• 2023

This study applied the stream physical habitat assessment system to obtain basic information for river restoration and watershed management in high-gradient and mid-gradient streams in the Naeseongcheon basin. The total length of high-gradient and mid-gradient streams in the Naeseongcheon basin is about 273 km, and as a result of the assessment, it was analyzed that suboptimal reach was about 8.2 km, normal reach was 180.3 km, and marginal reach was 84.7 km. In addition, the physical habitat quality of high-gradient streams was analyzed to be normal condition with an average of 106 points (53%), and in particular, the score of channel/hydraulic category, which is the most important for the habitat of aquatic animals, was analyzed to be normal, close to the limit, with an average of 54 points (45%). The physical habitat quality of mid-gradient streams was found to be in normal condition with an average of 90 points (45%), and the score of channel/hydraulic category was in marginal condition with an average of 39 points (32%). Overall, among 165 reaches of high-gradient and mid-gradient streams in the Naeseongcheon basin, 4 reaches (3%) were evaluated as suboptimal, 119 reaches (72%) were normal, and 42 reaches (25%) were considered marginal. These results showed that the physical habitat of Naeseongcheon was significantly disturbed. Disturbance of stream physical habitat in the Naeseongcheon basin occured due to farmland around stream, urbanization, reservoir construction, and river maintenance.