• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.9A
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• pp.772-780
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• 2005

In this paper, an efficient pre-processing in space tine block coded-spatial multiplexing systems is presented. The pre-processing scheme is designed empirically with extending the diagonally weighted orthogonal space time-block coded diversity system to spatial multiplexing system. Simulation results show the proposed scheme outperforms both the precoder using the predefued codebooks and typical antenna selection scheme over moderate doppler frequency in limited feedback channel.

• The KIPS Transactions:PartC
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• v.15C no.1
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• pp.1-8
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• 2008

The security of wireless sensor networks is a challenging research area where the resources constraints are a bottleneck for any successful security design. Due to their computational feasibility, symmetric key algorithms that require key pre-distribution are more desirable for use in these networks. In the pre-distribution scheme, keys or keying materials are assigned to each node prior deployment to guarantee a secure communication within the entire network. Though several works are introduced on this issue, yet the connectivity and resiliency are imperfectly handled. In this paper, we revisit the grid based key pre-distribution scheme aiming to improve the connectivity, introduce a higher resiliency level, simplify the logic of key establishment and maintain same level of used of resources usage. The core of our modification relies on introducing the novel plat-based polynomial assignment and key establishment mechanism. To demonstrate the advantageous properties of our scheme over the revisited one, details of consumed resources, resulting connectivity, security and comparisons with relevant works are introduced.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.780-791
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• 1996

A hybrid image processing system which automatically distinguished lean tissues in the image of a complex beef cut surface and generated the lean tissue contour has been developed. Because of the in homegeneous distribution and fuzzy pattern of fat and lean tissue on the beef cut, conventional image segmentation and contour generation algorithm suffer from a heavy computing requirement, algorithm complexity and poor robustness. The proposed system utilizes an artificial neural network enhance the robustness of processing. The system is composed of pre-network , network and post-network processing stages. At the pre-network stage, gray level images of beef cuts were segmented and resized to be adequate to the network input. Features such as fat and bone were enhanced and the enhanced input image was converted tot he grid pattern image, whose grid was formed as 4 X4 pixel size. at the network stage, the normalized gray value of each grid image was taken as the network input. Th pre-trained network generated the grid image output of the isolated lean tissue. A training scheme of the network and the separating performance were presented and analyzed. The developed hybrid system showed the feasibility of the human like robust object segmentation and contour generation for the complex , fuzzy and irregular image.

• Journal of Information Processing Systems
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• v.14 no.6
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• pp.1480-1493
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• 2018

Recently, computational intelligence has received a lot of attention from researchers due to its potential applications to artificial intelligence. In computer science, computational intelligence refers to a machine's ability to learn how to compete various tasks, such as making observations or carrying out experiments. We adopted a computational intelligence solution to monitoring residual resources in cloud computing environments. The proposed residual resource monitoring scheme periodically monitors the cloud-based host machines, so that the post migration performance of a virtual machine is as consistent with the pre-migration performance as possible. To this end, we use a novel similarity measure to find the best target host to migrate a virtual machine to. The design of the proposed residual resource monitoring scheme helps maintain the quality of service and service level agreement during the migration. We carried out a number of experimental evaluations to demonstrate the effectiveness of the proposed residual resource monitoring scheme. Our results show that the proposed scheme intelligently measures the similarities between virtual machines in cloud computing environments without causing performance degradation, whilst preserving the quality of service and service level agreement.

• Journal of information and communication convergence engineering
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• v.4 no.4
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• pp.166-169
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• 2006

Almost all network systems provide an authentication mechanism based on user ID and password. In such system, it is easy to obtain the user password using a sniffer program with illegal eavesdropping. The one-time password and challenge-response method are useful authentication schemes that protect the user passwords against eavesdropping. In client/server environments, the one-time password scheme using time is especially useful because it solves the synchronization problem. In this paper, we present a new identification scheme: OPI(One Pass Identification). The security of OPI is based on the square root problem, and OPI is secure: against the well known attacks including pre-play attack, off-line dictionary attack and server comprise. A number of pass of OPI is one, and OPI processes the password and does not need the key. We think that OPI is excellent for the consuming time to verify the prover.

• Journal of Information Processing Systems
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• v.18 no.1
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• pp.1-11
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• 2022

Online video telephony systems have been increasingly used in several industrial areas because of coronavirus disease 2019 (COVID-19) spread. The existing session initiation protocol (SIP)-based video call system is being usefully utilized, however, there is a limitation that it is very inconvenient for users to transmit additional information during conversation to the other party in real time. To overcome this problem, an enhanced scheme is presented based on augmented real-time reality (AR). In this scheme, augmented information is automatically searched from the Internet and displayed on the user's device during video telephony. The proposed approach was qualitatively evaluated by comparing it with other conferencing systems. Furthermore, to evaluate the feasibility of the approach, we implemented a simple network application that can generate SIP call requests and answer with AR object pre-fetching. Using this application, the call setup time was measured and compared between the original SIP and pre-fetching schemes. The advantage of this approach is that it can increase the convenience of a user's mobile phone by providing a way to automatically deliver the required text or images to the receiving side.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2003.06a
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• pp.161-164
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• 2003

This research presents the parallel control scheme of PID servo-driver for shaping of the curved glass. The designed system consists of a PC, main controller and 11 servo-drivers. Each elements are connected by using RS-232C and 8-bit bus communication. In order to guarantee the stability and the control performance, we use the LM629, a precision PID motion controller, and LMD18200, a H-bridge on the servo-drivers. PC calculates position values of 11 DC motors by using the pre-determined curvature value and offers the user interface environment operator.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.605-608
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• 1999

A conventional image coder, such as JPEG, requires not only DCT and quantization but also additional pre-filtering under noisy environment. Since the pre-filtering removes camera noise and improves coding efficiency dramatically, its efficient implementation has been an important issue. Based on well-known noise removal techniques in image processing fields, this paper introduces an efficient scheme by adapting a noise removal procedure to block-based image coders. By using two-dimensional DCT factorization, the proposed image coder has only a modified DCT and a VLC, and performs pre-filtering and quantization simultaneously in the modified DCT operation.

• Journal of the Institute of Convergence Signal Processing
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• v.5 no.1
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• pp.40-45
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• 2004

This paper presents the parallel distributed control scheme for shaping of the bent glass. The designed system consists of a PC, a main controller and 11 servo-controllers, the precision motion controllers. Each elements are connected by using RS-232C and 8-bit data bus. In order to guarantee the stability and the control performance, we use a precision PID motion controller and a H-bridge on the servo-drivers. PC calculates position values of 11 DC motors by using the pre-determined curvature value and offers the user interface environment operator. The main controller provides the control instructions and parameter values to 11 servo-controllers by chip enable signal, simultaneously. Using the received commands and parameter values, the servo-controllers control the positions of the DC motors based on PID control scheme.

• KIISE Transactions on Computing Practices
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• v.23 no.5
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• pp.293-298
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• 2017

Recently, much research has been devoted to implementing and provisioning high-performance computing environment using clusters with multiple computers and high-performance networking technologies. In-memory based Key-Value stores, such as Redis or Memcached, are widely used in high performance cluster environments to improve the data processing performance. We can distribute data at different storage nodes, and each computing node can access it at a high speed using these In-memory based Key-Value stores. InfiniBand is a de-facto technology that is widely used to interconnect each node of a cluster. In this paper, we propose a new data pre-fetching scheme for Key-Value store based on high performance clusters to improve the performance. The proposed scheme utilizes the data transfer characteristics of InfiniBand. The results of the simulation show that the proposed scheme can reduce the data transfer time by up to about 28%.