• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.8
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• pp.1010-1021
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• 1999

Camouflage measures in military purpose utilize the apparent temperature difference between target and background, so it is essential to develop a thermal analysis program for apparent temperature predictions and to apply some camouflage measures to real military targets for camouflage purpose. In this study, a thermal analysis program including conduction, convection and radiation is developed and the validity of radiation heat transfer terms is examined. The results show that longwave radiation along with solar radiation should be included in order to predict the apparent temperature as well as the physical temperature precisely. Longwave emissivity variation as an effective camouflage measures is applied to a real M2 tank. From the simulation results, it is found that an effective surface treatment, such as painting of a less emissive material or camouflage clothing, may provide a temperature similarity or a spatial similarity, resulting in an effective camouflage.

• 한국공간정보시스템학회:학술대회논문집
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• 2007.06a
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• pp.139-144
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• 2007

Recording data in hundreds of narrow contiguous spectral intervals, hyperspectral images have provided the opportunity to detect small differences in material composition. But a limitation of a hyperspectral image is the signal to noise ratio (SNR) lower than that of a multispectral image. This paper presents the efficiency of Spectral Similarity Scale (SSS) in change detection of hyperspectral image and the experiment was performed with Hyperion data. SSS is an algorithm that objectively quantifies differences between reflectance spectra in both magnitude and direction dimensions. The thresholds for detecting the change area were determined through Expectation-Maximization (EM) algorithm. The experimental result shows that the SSS algorithm and EM algorithm are efficient enough to be applied to the unsupervised change detection of hyperspectral images.

• Industrial Engineering and Management Systems
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• v.10 no.2
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• pp.123-127
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• 2011

Nowadays, green purchasing, stop global warming, love the mother earth, and others that related to environment become hot issues. Manufactures industries tend to more active and responsive to those issues by adopting green strategies or program like Environmentally Conscious Manufacturing (ECM). In this article, an electronic company had applied 12 ECM Program and tries to choose one of those programs using 6 criteria, such as total cost involved, quality, recyclable material, process waste reduction, packaging waste reduction, and regulation compliance. By using multi-criteria decision making model, i.e. Analytical Hierarchy Process (AHP), Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), and Modified TOPSIS methods, the ECM Program 9 (Open pit) is the best option.

• IE interfaces
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• v.10 no.3
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• pp.189-196
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• 1997

This paper presents a cell formation approach for a cellular manufacturing system to minimize the inter-cell moves considering operation sequences. Two new factors are introduced: (1)flow-similarity(FS) for integrating direct/indirect inter-machine flow and similarity (2)machine cell-part moves (CPM) for exactly computing inter-cell moves. FS is used for combining machines and CPM is used for assigning the parts to the preliminary machine cells. In addition, we develop an aggregated heuristic algorithm to form manufacturing machine cells and assign the parts to those cells based on these concepts. We use performance criterion called total inter-cell moves(TICM), which is the total material flow between internal cells and external cells. Results of computational tests on a number of randomly generated test problems show that the suggested heuristic is superior to existing methods.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.124-124
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• 2003

In order to study gene expression in a reproductive organ, we constructed a cDNA library of immature flower buds in Korean ginseng and generated expressed sequence tags (ESTs) of 3,360 clones randomly selected. The ESTs could be clustered into 1,844 non-redundant groups. Similarity search of the non-redundant ESTs against public non-redundant databases of both protein and DNA indicated that 1,254 groups show similarity to genes of known function. These ESTs clones were divided into sixteen categories depending upon gene function. The most abundant transcripts were unknown protein (72), chlorophyll a/b-binding protein (48), and stylar glycoprotein. There are no useful informations of gene expression during the development of flower bud in Korean ginseng. These results could help to understand the development of flower bud in Korean ginseng.

• Journal of the Korean Society of Safety
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• v.17 no.4
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• pp.38-44
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• 2002

The application of fractal concept provides an useful method in the study for the quantitative analysis of irregular variations like the fracture surfaces and crack profiles. Fractal curves have characteristics that represents a self-similarity based on the fractal dimension. The fractal dimensions were obtained by the box counting method. In this report, we obtained the nearly stable fractal dimensions of fracture crack profiles for STS316 with CT specimen as the crack advances and the relationships between crack length and fractal dimension. Moreover fractal fracture parameter that corresponds to J-R curve is shown by the relationships between fractal dimension and crack extension. From the results, we concluded that crack extension of high toughness material also shows the fractal characteristics, which can be used in order to evaluate the crack life precisely.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.3
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• pp.158-164
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• 1998

We introduce a statistical scheme to classify seabed from acoustic profiling data acquired using Chirp sonar system. The classification is based on grouping of signal traces by similarity index, which is computed using the K-L (Karhunen-Lo$\grave{e}$ve) transform of the Chirp profiling data. The similarity index represents the degree of coherence of bottom-reflected signals in consecutive traces, hence indicating the acoustic roughness of the seabed. The results of this study show that similarity index is a function of homogeneity, grain size of sediments and bottom hardness. The similarity index ranges from 0 to 1 for various types of seabed material. It increases in accordance with the homogeneity and softness of bottom sediments, whereas it is inversely proportional to the grain size of sediments. As a real data example, we classified the seabed off Cheju Island, Korea based on the similarity index and compared the result with side-scan sonar data and sediment samples. The comparison shows that the classification of seabed by the similarity index is in good agreement with the real sedimentary facies and can delineate acoustic response of the seabed in more detail. Therefore, this study presents an effective method for geoacoustic modeling to classify the seafloor directly from acoustic data.

• Journal of the Korean Society of Costume
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• v.58 no.4
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• pp.35-46
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• 2008

The purpose of this study was to closely examine the history of glasses and their cases used in the middle and late of Joseon Dynasty and identify inherent quality of our traditional glasses cases through color analyses of glasses cases' material and shape. While theoretical examination was conducted based on the literatures of glasses and their cases that firstly appeared in around Japanese Invasion (Imjin war) of Korea in 1592, practical analyses were demonstrated on photos of glasses cases used in the middle and late of Joseon Dynasty collected from both museum pieces and the internet which were grouped into wood, fabric, paper, sharkskin, hawksbill and cow's horn in accordance with their materials. 623 color samples were abstracted from collected 159 glasses cases and quantity analyses on each material were performed respectively. Abstracted representative colors based on the result of color analyses were classified into the main materials and accessories' color scheme. The result of this study are as follow: firstly, both Yellow and Yellow Red were mostly used in main materials. In Fabric case's colors were widely used in embroidery and in animal matter material cases such as sharkskin, hawksbill and cow's horn, which can be used as itself or dyed, Green Yellow shown in high frequency. Secondly, accessories were analyzed into similarity coloration with main materials. From this finding, it turns out that our traditional cases have characteristic of similarity coloration between main materials and accessories. Red Purple and Purple Blue in high frequency in accessories used as an accent color. Finally, based on the analysis of hue and tone, while the middle and low value colors shown in very high frequency, the high-chroma colors hardly shown.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.1
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• pp.35-42
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• 2008

Instrumented sharp indentation test is a well-directed method to measure hardness and elastic modulus. The sharp indenter such as Berkovich and conical indenters have a geometrical self-similarity in theory, but the self-similarity ceases to work in practice due to inevitable indenter tip-blunting. In this study we analyzed the load-depth curves of conical indenter with finite tip-radius via finite element method. Using the numerical regression data obtained from Kick's law, we first confirmed that loading curvature is significantly affected by tip radius as well as material properties. We then established a new method to evaluate Young's modulus, which successfully provides the value of elastic modulus with an average error of less than 2%, regardless of tip-radius and material properties of both indenter and specimen.

• Corrosion Science and Technology
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• v.4 no.5
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• pp.211-216
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• 2005

Failure analysis of the latch ram ball and the C-ram ball with the trade name AFBMA Gr. 50 Colmonoy No. 6, has been performed to identify the root cause of the failure. The study required the extraction of the both failed and normal balls from the nuclear fuel exchanger. Microstructures of both balls were examined after polishing and etching. Breaking tests of both the ball revealed similarity in cleavage surfaces. Fracture surfaces of both failed ball and normal ball after breaking test were examined with SEM and EDX. Microstructure of the ball revealed an austenite phase with coarse Cr rich precipitate. Indented marks observed on the surface of the failed ball are believed to be produced by overloading. In the light of the afore mentioned observations and studies, the failure mechanism of the ball in nuclear fuel exchanger seem to be caused by impact or mechanical overloading on ball.