• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.3C
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• pp.119-124
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• 2005

In this paper, we propose a novel algorithm for determining the variable size of locally adaptive window using region-merging method. A region including a denoising point is partitioned to disjoint sub-regions. Locally adaptive window for denoising is obtained by selecting Proper sub-lesions. In our method, nearly arbitrarily shaped window is achieved. Experimental results show that our method outperforms other critically sampled wavelet denoising scheme.

• Wind and Structures
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• v.17 no.2
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• pp.185-202
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• 2013

The goal of this study was to investigate the vulnerability of roof tile systems and metal shutters to roof tile debris. Three phases addressed the performance of tile roof systems and metal shutters impacted by roof tile debris. The first phase experimentally evaluated the tile fragment size and quantity generated by a tile striking a tile roof system. The second phase experimentally quantified the puncture vulnerability of common metal panel shutter systems as a function of tile fragment impact speed. The third phase provided context for interpretation of the experimental results through the use of a tile trajectory model. The results provide supporting evidence that while metal panel window shutters provide significant protection against a prevalent form of windborne debris, these systems are vulnerable to tile fragment puncture in design level tropical cyclones. These findings correlate with field observations made after Hurricane Charley (2004).

• Proceedings of the KIEE Conference
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• 1987.07b
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• pp.1174-1177
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• 1987

The design of flow control protocols for integrared networks with complete voice traffic on the data link level is investigated. The class of admissible flow control policies analyzed maximized the average data link throughput subject to an average system time delay constraints a finite intervals (O,s). In particular, it is shown that the optimum control law is bang-bang (window flow mechanism). The window size L can be analytically derived from maximum tolerated time delay T, the input arrival C of the queueing system, the duration of the time interval S, the initial number of packets in the queue.

• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.27-30
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• 2002

In this paper, we propose a window-based congestion control algorithm to achieve a fair sharing of the available bandwidth in ECN capable heterogeneous TCP networks with a single bottleneck link. The proposed algorithm is based on extracting the network status from the successive binary congestion information provided by ECN. From the explicit network information, we estimate the fair window size proportional to the propagation delay. Through simulations, the effect and performance of the proposed algorithm are shown for the heterogeneous networks.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.265-266
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• 1998

This paper describes a depth extraction algorithm in the stereo endoscopic images using adaptive window. First, The relation between the 3D coordinates in the world and the 2D coordinates in the image plane is estimated using camera calibration. Next, stereo matching is performed to find the conjugate pairs in the left and right images. To improve the precision of the matching result, adaptive window which can be varied on the shape as well as on the size according to the area characteristics is used. Finally, the result from the stereo matching and that of camera modeling are combined to extract the real depth information.

• Communications of the Korean Institute of Information Scientists and Engineers
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• v.5 no.2
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• pp.49-60
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• 1987

To decide on the queuing system of the optimum-sized bank window, data by means of simulation was reckoned. That is, by linking the average arrival rate and the average service rate with the exponential random number, customers' arrival time and service time was reckoned and simulation size optionally decided. By so doing, this paper is aimed at predicting the conditions of a bank, average arrival time, average waiting time, aveerage service time, average queuing length, servers' idle time, etd, and at preparing for a simulation model of the queuing system that can apply not only to the bank window box but also to all system under which queuing phenomena may arise.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2070-2075
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• 2008

Identification of steady-state is the first step in developing a fault detection and diagnosis (FDD) system. In a complete FDD system, the steady-state detector will be included as a module in a self-learning algorithm which enables the working system's reference model to "tune" itself to its particular installation. In this study, a steady-state detector of a residential air conditioner based on moving windows was designed. Seven representing measurements were selected as key features for steady-state detection. The optimized moving window size and the feature thresholds was suggested through startup transient test and no-fault steady-state test. Performance of the steady-state detector was verified during indoor load change test. From the research, the general methodology to design a moving window steady-state detector was provided for vapor compression applications.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.9
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• pp.3110-3125
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• 2014

Network coding improves TCP's performance in lossy wireless networks. However, the complex congestion window evolution of network coded TCP (TCP-NC) makes the analysis of end-to-end throughput challenging. This paper analyzes the evolutionary process of TCP-NC against lossy links. An analytic model is established by applying a two-dimensional Markov chain. With maximum window size, end-to-end erasure rate and redundancy parameter as input parameters, the analytic model can reflect window evolution and calculate end-to-end throughput of TCP-NC precisely. The key point of our model is that by the novel definition of the states of Markov chain, both the number of related states and the computation complexity are substantially reduced. Our work helps to understand the factors that affect TCP-NC's performance and lay the foundation of its optimization. Extensive simulations on NS2 show that the analytic model features fairly high accuracy.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.04a
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• pp.1136-1139
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• 2009

본 논문은 802.15.4에서 CW(Contention Window)에 따른 성능과 에너지 소비량을 분석한다. 기존 연구에서는 802.15.4 표준안의 성능과 에너지 소비량을 분석하고, CW나 BE(Backoff Exponent)와 같은 변수를 변화시켜 시뮬레이션만으로 성능과 에너지 소비량을 비교하여 분석하였으나, 본 논문은 CW에 따른 성능과 에너지 소비량을 마코프 체인(Markov Chain)을 이용하여 수학적으로 분석을 하였다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.6
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• pp.307-315
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• 2010

Although a substantial amount of studies have been carried out in order to improve the performance of IEEE 802.11, most of them focused on how to slowly decrease the Contention Window size, instead of resetting it to its initial value. Slow decreasing of the window size reduces the collision probability and increases the channel throughput. Therefore, it is difficult to achieve good results in a heterogeneous network which coexists with the original DCF. For instance, a Gentle DCF(GDCF) has good performance in a homogeneous environment, while it can hardly transmit frames in a heterogeneous environment including the original DCF. It is because the slow decreasing of the window size reduces the transmission probability. In this paper, we propose a Fast Recovery DCF(FRDCF) to solve this problem. In the FRDCF, the reset mechanism of the original DCF is maintained to keep the transmission probability high, while a new counter is used to enhance the performance of the wireless LAN. We prove that, compared with the GDCF, the FRDCF has better performance in a heterogeneous wireless LAN.