• Earthquakes and Structures
• /
• v.14 no.2
• /
• pp.129-142
• /
• 2018

The current paper introduces a new approach for development of damage index to obtain the maximum damage in the reinforced concrete frames caused by as-recorded single and consecutive earthquakes. To do so, two sets of strong ground motions are selected based on maximum and approximately maximum peak ground acceleration (PGA) from "PEER" and "USGS" centers. Consecutive earthquakes in the first and second groups, not only occurred in similar directions and same stations, but also their real time gaps between successive shocks are less than 10 minutes and 10 days, respectively. In the following, a suite of six concrete moment resisting frames, including 3, 5, 7, 10, 12 and 15 stories, are designed in OpenSees software and analyzed for more than 850 times under two groups of as-recorded strong ground motion records with/without seismic sequences phenomena. The idealized multilayer artificial neural networks, with the least value of Mean Square Error (MSE) and maximum value of regression (R) between outputs and targets were then employed to generate the empirical charts and several correction equations for design utilization. To investigate the effectiveness of the proposed damage index, calibration of the new approach to existing real data (the result of Park-Ang damage index 1985), were conducted. The obtained results show good precision of the developed ANNs-based model in predicting the maximum damage of regular reinforced concrete frames.

• The Journal of Korean Medicine
• /
• v.22 no.3
• /
• pp.63-73
• /
• 2001

Objectives : The objective of the current study is to determine the protective effect of Ukyium(Yougui-yin) on the apoptosis induced by zinc. Methods : Zinc is known to generate reactive oxygen species (ROS), including superoxide anion ($O_2$) and hydrogen peroxide ($H_2O_2$), which eventually contribute to cytotoxicity in a variety of cell types. We investigated the viablity of cells, $H_2O_2$ generation, chromatin condensation and nuclear fragmentation in Hoechst dye staining and $IkB-{\alpha}$ degradation in C6 glial cells of $ZnCl_2$ between pretreatment- and not pretreatment-group with Ukyium. The former methods were researched by Time- and Dose-dependent manners. Results : We demonstrated that pretreatment with Ukyium prevented zinc-induced cell death of C6 glial cells and apoptotic characteristics including chromatin condensation and nuclear fragmentation. Ukyium also prevented $H_2O_2-induced$ cell death. We further confirmed that Ukyium decreased zinc-induced generation of $H_2O_2$ and inhibited degradation of $IkB-{\alpha}$ by zinc in C6 glial ceHs. Conclusions : These data indicated that Ukyium (Yougui-yin) prevents zinc-induced apoptotic death of C6 glial cells via inhibition of ROS generation, such as $H_2O_2$ as well as inhibition of $IkB-{\alpha}$ degradation.

• Journal of Korean Society of Forest Science
• /
• v.84 no.1
• /
• pp.63-70
• /
• 1995

This paper discusses applications of neural network to stand stocking control problems. The scope of this research was to develop a neural network model for finding optimal stand management regimes and examining the performance of the model for field application. Performance was analyzed in consideration of the number of training examples and structural aspects of neural network. Research on network performance was based on extensive optimization studies for pure longleaf pine(Pinus palustris) stands. For experimental purposes. an existing nonlinear even-aged stand optimization model with a whole-stand growth and yield simulator was used to generate data samples required for the performance analysis.

• The Journal of the Acoustical Society of Korea
• /
• v.10 no.1
• /
• pp.47-51
• /
• 1991

it is well observed in the ocean that the surface disturbances due to rain, wind and breaking waves generate bubble clouds several meters deep from the water surfaces. Thses kinds of bubble clouds can work as a physical mechanism to produce underwater ambient noise. In the laboratory experiment observing the noise generated from a bubble cloud we showed a role of individual bubbles in collective oscillations of a bubble cloud. The experimental data agree very well with the theoretical predictions. These results confirm that the collective oscillations of a bubble cloud is one of the more likely mechanisms for an ocean ambient noise source around several hundred hertz.

• The Journal of Society for e-Business Studies
• /
• v.9 no.2
• /
• pp.17-31
• /
• 2004

It is very important that sellers provide reasonable reserve prices for auction items in internet auction systems. Recently, an agent has been proposed to generate reserve prices automatically based on the case similarity of information retrieval theory. However, one of its drawbacks is that the recent trend of auction prices is not reflected in the generated reserve prices, because it suggests the bid price of the most similar item from the past auction data. In this paper, in order to overcome the problem, we propose a new method that generates reserve prices based on the moving average of time series analysis, in which more weight is provided to the recent bid prices. Through performance experiments, we show that the successful bid rate can be increased by preventing sellers from making unreasonable reserve prices.

• The Journal of Society for e-Business Studies
• /
• v.12 no.3
• /
• pp.19-31
• /
• 2007

In this research, we propose the operational method of the RFID-based NPI (National Product Identifier) which can manage product assets for the Korean government in the future. First of all, we present the operational concept of the national product asset management. Second, we suggest the structure of the NPI which accommodates ISO/IEC 15459 and the method to encode NPI and related data to ISO/IEC 18000-6C tags. Finally, we propose the operational business processes to generate and manage NPI in the stages of product procurement and product asset management.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.10 no.3
• /
• pp.446-452
• /
• 2006

In this paper, I evaluated the throughput of various multimedia traffic by using computer simulation over wireless LAN environment based on 802.11e MAC protocol. The number of mobile terminals which generate various traffic and have different Internet QoS varies to improve the reliability of performance evaluation by simulation. Therefore, we investigate throughput of traffic that each mobile terminal generates. I expect that the result of study will be utilized as a fundamental data to control priorities of various types of traffic in case of formulating a scheduling policy supporting a variety of Internet QoS over wired and wireless networks.

• Journal of Navigation and Port Research
• /
• v.33 no.6
• /
• pp.451-456
• /
• 2009

In this paper, we presents an algorithm which generates its high-resolution DTM using a low-resolution DTM of the sea floor terrain and fractal theory. The fractal dimension of each patch region divided from the DTM is extracted and then with this information and original data, each cell region in the patch is interpolated using the midpoint displacement method and a median filter is incorporated to generate natural and smooth sea floor surface. The effectiveness of the proposed algorithm is tested on a fractal terrain map.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2009.01a
• /
• pp.351-354
• /
• 2009

Distributed video coding (DVC) is a new coding paradigm that enables to exploit the statistics among sources only in decoder and to achieve extremely low complex video encoding without any loss of coding efficiency. Wyner-Ziv coding, a particular implementation of DVC, reconstructs video by correcting noise on side information using channel code. Since a good quality of side information brings less noise to be removed by the channel code, generation of good side information is very important for the overall coding efficiency. However, if there are complex motions among frames, it is very hard to generate a good quality of side information without any information of original frame. In this paper, we propose a method to enhance the quality of the side information using small amount of additional information of original frame in the form of hash. By decoder's informing encoder where the hash has to be transmitted, side information can be improved enormously with only small amount of hash data. Therefore, the proposed method gains considerable coding efficiency. Results of our experiment have verified average PSNR gain up to 1 dB, when compared to the well-known DVC codec, known as DISCOVER codec.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.27 no.8
• /
• pp.1418-1425
• /
• 2003

In CAD systems, a surface to be machined is expressed by a series of curves, such as B-spline, Bezier and NURBS curves, which compose the surface and then in CAM systems the curves are divided into a large number of line or arc segments. These divided movement commands, however, cause many problems including their excessive size of NC data that makes almost impossible local adjustment or modification of the surface. To cope with those problems, the necessity of real-time curve or surface interpolators was embossed. This paper presents an efficient real-time tool-path generation method fur interpolation of NURBS surfaces in CNC machining. The proposed tool-path generation method is based on an improved iso-scallop strategy and can provide better precision than the existing methods. The proposed method is designed such that tool-path planning is easily managed in real-time. It proposed a new algorithm for regulation of a scallop height, which can efficiently generate tool-paths and can save machining time compared with the existing method. Through computer simulations, the performance of the proposed method is analyzed and compared with the existing method in terms of federate, total machining time and a degree of constraint on the scallop height.