• International Journal of Computer Science & Network Security
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• v.22 no.3
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• pp.285-291
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• 2022

WSN is the major component for information transfer in IoT environments. Source Location Privacy (SLP) has attracted attention in WSN environments. Effective SLP can avoid adversaries to backtrack and capture source nodes. This work presents a Two-Level Randomized Sector-based Routing (TLRSR) model to ensure SLP in wireless environments. Sector creation is the initial process, where the nodes in the network are grouped into defined sectors. The first level routing process identifies sector-based route to the destination node, which is performed by Ant Colony Optimization (ACO). The second level performs route extraction, which identifies the actual nodes for transmission. The route extraction is randomized and is performed using Simulated Annealing. This process is distributed between the nodes, hence ensures even charge depletion across the network. Randomized node selection process ensures SLP and also avoids depletion of certain specific nodes, resulting in increased network lifetime. Experiments and comparisons indicate faster route detection and optimal paths by the TLRSR model.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.38 no.5
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• pp.498-508
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• 2001

In this paper, we propose an efficient coding algorithm for the zoom images to find the optimal depth and texture information. The proposed algorithm is the area-based method consisting of two consecutive steps, i) the depth extraction step and ii) the texture extraction step. The X-Y plane of the object space is divided into triangular patches and the depth value of the node is determined in the first step and then the texture of the each patch is extracted in the second step. In the depth extraction step, the depth of the node is determined by applying the block-based disparity compensation method to the windowed area centered at the node. In the second step, the texture of the triangular patches is extracted from the zoom images by applying the affine transformation based disparity compensation method to the triangular patches with the depth value extracted from the first step. To improve the quality of image, the interpolation is peformed on the object space instead of the interpolation on the image plane.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.10
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• pp.79-88
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• 2003

We demonstrate a novel all-optical packet switching system that is suitable for optical ring networks. For the demonstration, video signals are encoded into optical packets which are composed of header and payload. The optical packets are all-optically processed at a switching node based on all-optical header processor, packet-level clock extraction, bit-level clock extraction, all-optical data format converter and so on.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.9B
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• pp.589-597
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• 2007

In this paper, a WDM metro ring consisting of access nodes with $FT-FR^n$ (Fixed Transmitter - n Fixed Receivers) is considered. A trade-off exists between node throughput and transmission fairness because the access nodes share wavelength channels. In order to eliminate the transmission unfairness and to increase throughput, the p-persistent medium access control (MAC) protocol is proposed: each node uses an empty optical slot to transmit a packet and make it available with the extraction of a transferred packet at the source access node, called source-stripping. The local empty slot can be used to transfer a head-of-line packet in the local buffer with probability p or it is used for the next downstream nodes with 1-p. The proposed MAC protocol provides better node throughput than the non-persistent protocol and exhibits better fairness index than the 1-persistent protocol in WDM ring networks. In addition, numerical analysis shows that the proposed MAC protocol maximizes the node throughput under uniform traffic conditions. For more detailed results, we use the network simulation under Poisson and self-similar traffic. Furthermore, unpredictable traffic constructed by the combination of the former and the latter is also considered. The reasonable probability of the p-persistent protocol for a given architecture can be determined through simulation.

• Journal of Korea Society of Industrial Information Systems
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• v.6 no.2
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• pp.7-15
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• 2001

In this paper, we suggest the algorithm that inserts or deletes documents into web sites without creating tag. This algorithm uses tag which links between documents to automatically inset or delete the web documents. This study extracts the texts in the ... tag of the document to put into the structure as a type of graph creating the link as a node m of sub-node. That is, in this case of configurating new link between web documents, this algorithm allows to insert or delete the node to or from the graph without creating the tag. In the case of deleting the document, it removes the broken link connecting the sub-nodes of deleted node newly to its parent node.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.3
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• pp.978-983
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• 2010

Acoustic target classification in wireless sensor network is important research at environmental surveillance, invasion surveillance, multiple target separation. General sensor node signal processing methods concentrated on received signal energy based target detection and received raw signal compression. The former is not suited to target classification because of almost every target information are lost except target energy. The latter bring down life-time of sensor node owing to high computational complexity and transmission energy. In this paper, we introduce an feature extraction algorithm for acoustic target classification in wireless sensor network which has time and frequency information. The proposed method extracts time information and de-noised target classification information using wavelet decomposition step. This method reduces communication energy by 28% of original signal and computational complexity.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.773-776
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• 1998

In this paper, we propose an efficient multi-view images coding algorithm which finds the optimal texture from the restricted number of multi-view images. The X-Y plane of the normalized object space is divided into triangular patches. The depth value of the node is determined by applying the block based disparity compensation method and then the texture of the each patch is extracted by applying the affine transformation patch is extracted by applying the affine transformation based disparity compensation method to the multi-view images. We restricted the number of images contributed to determining the texture comapred to traditional methods which use all the multi-view images in the texture extraction. Experimental results show that the SNR of images encoded by the proposed algorithm is better than that of imaes encoded by the traditional method by the amount about 0.2dB for the test sets of multi-view images called dragon, kid, city and santa. The recovered images from the encoded data by the proposed method show the better visual images than the recovered images from the encoded data by the traditional methods.

• Journal of Gastric Cancer
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• v.16 no.1
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• pp.51-53
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• 2016

Laparoscopic gastrectomy for cancer has some significant postoperative benefits over open surgery with similar oncologic outcomes. This procedure is more popular in the Far East countries where obesity is not a serious public health problem. In the Western countries, laparoscopic gastrectomy for cancer is not a common procedure, yet obesity is more common. Herein, we aimed to demonstrate the feasibility of laparoscopic gastrectomy for advanced gastric cancer in a morbidly obese patient. Additionally, we used natural orifice specimen extraction as an option to decrease wound-related complications, which are more prevalent in morbidly obese patients. In this case, we performed a fully laparoscopic subtotal gastrectomy with lymph node dissection and Roux-en-Y gastrojejunostomy with the specimen extracted through the vagina. To the best of our knowledge, this was the first report of a natural orifice surgery in a morbidly obese patient with gastric cancer.

• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.6
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• pp.981-987
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• 1986

This paper describes the CIREX(CIRcuit EXtractor), an automated CMOS circuit extraction program which provides SPICE2 input file by computing circuit connectivity and transistor dimensions from the CIF file. The CIREX also computes parasitic capacitance and resistance which makes it a valuable tool for timing analysis and detailed circuit simulation. A lattice model is used to calculate the interconnection resistances and substrate capacitances which can be replaced, as an option, by a node model for the worst case timing analysis of the circuit.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.7
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• pp.793-801
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• 1992

This paper proposes a method of extracting connected strokes and characters in a Hangeul document image represented by a quadtree. Connected strokes are extracted by examining adjacency for each node of a black region to the side of east and south. Then, each character is extracted by the sizes and the relations of connected strokes. This is done by iterative vertical and horizontal manipulation. The result shows all characters are extracted in the same sequence as that of context with space and time efficiency.