• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.3
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• pp.7-12
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• 2012

Ceramic core processing technology using 5-axis high-speed cutting machine is applied to make the glass molds for aspherical ophthalmic lenses. In the technology, optimum processing conditions for aspherical ceramic molds are based on minimal experimental data of surface roughness. Such surface roughness is influenced by fabricating tools, cutting speed, feed rate, and depth of cut, respectively. In this paper, we present that surface roughness and shape accuracy of aspheric ceramic mold obtained by optimum processing conditions are Pa $0.6184{\mu}m$ and Pt $5.0301{\mu}m$, respectively, and propose that these values are sufficiently possible to apply to making the glass molds for aspherical ophthalmic lenses.

• Journal of the Optical Society of Korea
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• v.17 no.1
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• pp.68-72
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• 2013

We developed an SD-OCT (Spectral Domain-Optical Coherence Tomography) system which uses a GPU (Graphics Processing Unit) for processing. The image size from the SD-OCT system is $1024{\times}512$ and the speed is 110 frame/sec in real-time. K-domain linearization, FFT (Fast Fourier Transform), and log scaling were included in the GPU processing. The signal processing speed was about 62 ms using a CPU (Central Processing Unit) and 1.6 ms using a GPU, which is 39 times faster. We performed an in-vivo retinal scan, and reconstructed a 3D visualization based on C-scan images. As a result, there were minimal motion artifacts and we confirmed that tomograms of blood vessels, the optic nerve, and the optic disk are clearly identified. According to the results of this study, this SD-OCT can be applied to real-time 3D display technology, particularly auxiliary instruments for eye operations in ophthalmology.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.2122-2122
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• 2001

The ultra-high pressure technology fur the preservation of foods is under intense research to evaluate its potential as an alternative or complementary process to traditional methods of food preservation. Traditional processing methods usually need a large amount of energy, may cause unwanted reactions in the food, leading to cooked flavor and loss of vitamins, etc. The application of ultra-high hydrostatic pressure for food processing consists of subjecting the food to pressures in the range of 100-1000 ㎫. The ultra-high pressure inactivates the microorganisms and some enzymes, promotes the germination of spores and extends the shelf-life of the foods. This new technology follows the “minimal processing” concept minimizing the quality degradation, saving the vitamins, essential nutrients and flavors as well as utilizing less energy. We joined the research team at our University involved in the mentioned technology using an ultra-high pressure equipment, recording of the near infrared spectra and signal response of a chemosensor array (electronic nose) of their meat (beef and pork), vegetable and fruit samples exposed to different pressure. The results of our investigations achieved by evaluating the measured data using PCA and PQS methods will be presented.

• Journal of Industrial Technology
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• v.3
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• pp.87-94
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• 1983

Heating characteristics of red pepper paste packed in report pouches of various thicknesses and their storage stability were investigated to determine the adequate processing conditions that good bacteriological safty and minimal quality changes could be obtained, when sterilized by using a steam-air system retort. A heat penetration into pouch-packed red pepper paste was carried out through by a conductive heat transfer, indicating a simple logarithmic heating curve, and the smaller thickness revealed the higher heat penetration rate, suggesting the possibility of high temperature-short time sterilization of red pepper paste. The processing conditions with Fo-value of 4.5 or higher were sufficient for keeping up bacterial safty, but based on C-value, better quality retention was obtained at pouch thickness of 15mm under the processing temperature of $120^{\circ}C$. Subsequent storage study revealed that the red pepper paste packed in 15mm and processed at $120^{\circ}C$ with Fo=4.5 could be held without any spoilage and overall acceptance change, when stored for 6 months at room temperature under the relative humidity of 70%. After 3 months storage in $38^{\circ}C$ under saturation humidity, overall acceptance of red pepper paste were judged not to be maintainable on the acceptable level, but it may be suggested that above the results could be kept up a desirable quality without any remarkable deterioration.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.6
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• pp.1073-1080
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• 2011

In this study, a target detection algorithm was proposed for using hyperspectral imagery. The proposed algorithm is designed to have minimal processing time, low false alarm rate, and flexible threshold selection. The target detection procedure can be divided into two steps. Initially, candidates of target pixel are extracted using matching ratio of spectral pattern that can be calculated by spectral derivation. Secondly, spectral distance is computed only for those candidates using Euclidean distance. The proposed two-step method showed lower false alarm rate than the Euclidean distance detector applied over the whole image. It also showed much lower processing time as compared to the Mahalanobis distance detector.

• Journal of Information Processing Systems
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• v.20 no.3
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• pp.307-316
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• 2024

In the realm of large-scale identification deployments, the EPCglobal Class-1 Generation-2 (Gen2) standard serves as a cornerstone, facilitating rapid processing of numerous passive RFID tags. The Q-Algorithm has garnered considerable attention for its potential to markedly enhance the efficiency of Gen2-based RFID systems with minimal adjustments. This paper introduces a groundbreaking iteration of the Q-Algorithm, termed Time-Efficient Q-Algorithm (SwiftQ), specifically designed to push the boundaries of time efficiency within Gen2-based RFID systems. Through exhaustive simulations, our study substantiates that SwiftQ outperforms existing algorithms by a significant margin, demonstrating exceptional expediency that positions it as a formidable contender in the landscape of large-scale identification environments. By prioritizing time efficiency, SwiftQ offers a promising solution to meet the escalating demands of contemporary Internet of Things applications, underscoring its potential to catalyze advancements in RFID technology for diverse industrial and logistical contexts.

• The Korean Journal of Food & Health Convergence
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• v.5 no.6
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• pp.17-21
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• 2019

This article addresses issues related to environmental pollution.Particular attention is paid to the prevention of environmental pollution by livestock waste, which prompted the creation of closed ecological and biotechnical systems as environmentally closed production structures that can fit into the equilibrium system of the environment with minimal damage to it. An energy-saving and environmental protection technology for the processing and disposal of livestock waste with a maximum coefficient of energy transfer to livestock products has been developed, which consists in a combined treatment of waste in three stages, by transferring waste from one technological module to another, which makes it possible to completely utilize mineral substances in waste. The focus is on vermicultivation, microalgae cultivation and anaerobic fermentation in a bioenergy plant. To increase the productivity of growing microalgae, the authors proposed a deep type cultivator with submerged movable light sources.The technological parameters of the bioenergy installation for waste treatment are determined. An energy-saving and environmental-friendly technology has been developed for processing The main contribution of the study is the development of energy-saving and environmental technology for the processing and disposal of livestock waste with a maximum coefficient of energy transfer to livestock products.

• Journal of Information Processing Systems
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• v.14 no.6
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• pp.1347-1360
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• 2018

Owing to limited energy in wireless devices power saving is very critical to prolong the lifetime of the networks. In this regard, we designed a cross-layer optimization mechanism based on power control in which source node broadcasts a Route Request Packet (RREQ) containing information such as node id, image size, end to end bit error rate (BER) and residual battery energy to its neighbor nodes to initiate a multimedia session. Each intermediate node appends its remaining battery energy, link gain, node id and average noise power to the RREQ packet. Upon receiving the RREQ packets, the sink node finds node disjoint paths and calculates the optimal power vectors for each disjoint path using cross layer optimization algorithm. Sink based cross-layer maximal minimal residual energy (MMRE) algorithm finds the number of image packets that can be sent on each path and sends the Route Reply Packet (RREP) to the source on each disjoint path which contains the information such as optimal power vector, remaining battery energy vector and number of packets that can be sent on the path by the source. Simulation results indicate that considerable energy saving can be accomplished with the proposed cross layer power control algorithm.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.12
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• pp.102-107
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• 2009

As technology gets developed, medical equipments are also modernized and leading-edge systems, such as PACS become popular. Many scientists noticed importance of medical image processing technology. Technique of region segmentation is the first step of digital medical image processing. Segmentation technique helps doctors to find out abnormal symptoms early, such as tumors, edema, and necrotic tissue, and helps to diagnoses correctly. Segmentation of white matter, gray matter and CSF of a brain image is very crucial part. However, the segmentation is not easy due to ambiguous boundaries and inhomogeneous physical characteristics. The rate of incorrect segmentation is high because of these difficulties. Fuzzy-based segmentation algorithms are robust to even ambiguous boundaries. In this paper a modified Fuzzy-based segmentation algorithm is proposed to handle the noise of MR scanners. A proposed algorithm requires minimal computations of mean and variance of neighbor pixels to adjust a new neighbor list. With the addition of minimal compuation, the modified FCM(mFCM) lowers the rate of incorrect clustering below 30% approximately compared the traditional FCM.

• Annual Conference on Human and Language Technology
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• 1998.10c
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• pp.419-424
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• 1998

본 논문에서는 단어들의 분포적 특성을 이용하여 자동으로 단어를 군집화(clustering) 하는 기법을 제시한다. 제안된 군집화 기법에서는 단어들 사이의 거리(distance)를 가상 공간상에 있는 두 단어의 평균점에 대한 불일치의 합(total divergence to the average)으로 측정하며 군집화 알고리즘으로는 최소 신장 트리(minimal spanning tree)를 이용한다. 본 논문에서는 이 기법에 대해 두 가지 실험을 수행한다. 첫 번째 실험은 코퍼스에서 상위 출현 빈도를 가지는 약 1,200 개의 명사들을 의미에 따라 군집화 하는 것이며 두 번째 실험은 이 논문에서 제시한 자동 군집화 방법의 성능을 객관적으로 평가하기 위한 것으로 가상 단어(pseudo word)에 대한 군집화이다. 실험 결과 이 방법은 가상 단어에 대해 약 91%의 군집화 정확도와(clustering precision)와 약 81%의 군집 순수도(cluster purity)를 나타내었다. 한편 두 번째 실험에서는 평균점에 대한 불일치의 합을 이용한 거리 측정에서 나타나는 문제점을 보완한 거리 측정 방법을 제시하였으며 이를 이용하여 가상 단어 군집화를 수행한 결과 군집화 정확도와 군집 순수도가 각각 약 96% 및 95%로 향상되었다.