• The Journal of Korea Robotics Society
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• v.14 no.4
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• pp.278-284
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• 2019

Legged locomotion has high mobility on irregular surfaces by touching the ground at discrete points. Inspired by the creature's legged locomotion, legged robots have been developed to explore unstructured environments. In this paper, we propose a modular crawler that can easily adjust the number of legs for adapting the environment that the robot should move. One module has a pair of legs, so the number of legs can be adjusted by changing the number of modules. All legs are driven by a single driving motor for simple and compact design, so the driving axle of each module is connected by the universal joint. Universal joints between modules enable the body flexion for steering or overcoming higher obstacles. A prototype of crawler with three modules is built and the driving performance and the effect of module lifting on the ability to overcome obstacles are demonstrated by the experiments.

• Journal of the Optical Society of Korea
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• v.17 no.6
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• pp.543-547
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• 2013

A temperature dependent (10K-290K) photoluminescence (PL) study for two differently prepared ZnO thin films (as-grown and O-plasma treated) is presented. Four characteristic peaks were identified for both samples: (i) neutral donor-bound excitons ($D^oX$), (ii) two electron satellites (TES), (iii) phonon replica of $D^oX$ ($D^oX$-1LO), and (iv) donor-acceptor pair transition (DAP). As the sample temperature increased, $D^oX$-1LO and DAP transitions became indistinct. This was accompanied by newly-rising emission of free electron-acceptor transitions (e, $A^o$). The spectral evolution with temperature for as-grown samples also showed the optical emission from free excitons, which became dominant at higher temperatures. Some features related to O-plasma were identified in PL spectra: (i) different positions of TES transitions (28meV lower than $D^oX$ for as-grown samples and 35meV for O-plasma treated samples), (ii) the decrease of spectral intensity in both emissions of $D^oX$ and DAP after O-plasma treatment, and (iii) no noticeable transition from free excitons after the O-plasma treatment.

• Journal of Information Processing Systems
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• v.17 no.2
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• pp.213-226
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• 2021

Given that most of the link prediction algorithms for signed social networks can only complete sign prediction, a novel algorithm is proposed aiming to achieve both link prediction and sign prediction in signed networks. Based on the structural balance theory, the local link tightness and global link tightness are defined respectively by using the structural information of paths with the step size of 2 and 3 between the two nodes. Then the total similarity of the node pair can be obtained by combining them. Its absolute value measures the possibility of the two nodes to establish a link, and its sign is the sign prediction result of the predicted link. The effectiveness and correctness of the proposed algorithm are verified on six typical datasets. Comparison and analysis are also carried out with the classical prediction algorithms in signed networks such as CN-Predict, ICN-Predict, and PSNBS (prediction in signed networks based on balance and similarity) using the evaluation indexes like area under the curve (AUC), Precision, improved AUC', improved Accuracy', and so on. Results show that the proposed algorithm achieves good performance in both link prediction and sign prediction, and its accuracy is higher than other algorithms. Moreover, it can achieve a good balance between prediction accuracy and computational complexity.

• Textile Coloration and Finishing
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• v.31 no.2
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• pp.65-76
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• 2019

A multi-point touch input sensor having different sizes or different capacitance touch points connected by only one pair of signal transmission lines was fabricated using a polyimide film coated with a thin copper plate. The capacitance increases with the decrease in the number of sheets of fabric spacers placed between the two sheets of the polyimide film. Therefore, the touch input sensor could be manufactured without fabric spacers, which was possible by the action of the polyimide film as a dielectric material in the capacitor. On the multi-point touch sensor, higher capacitance was obtained when pressing wider-area touch points with 10mm to 25mm diameter on average. However, the capacitance of a system comprising two sheets of touch sensors was considerably low, causing a serious overlap of the capacitance values according to the data collected from the reliability test. Although the capacitance values could be increased by stacking several sheets of touch sensors, the overlap of data was still observed. After reducing the size of all touch points to 10mm and stacking up to eight sheets of sensors, reliable and consistent capacitance data was obtained. Five different capacitance signals could be induced in the sensors by pushing touch points simultaneously.

• Journal of Drive and Control
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• v.19 no.4
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• pp.1-9
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• 2022

The structure and operating principle of the 2-speed shift reducer were explained, the allowable bending stress value of the material was compared with the analysis result through FM structural analysis program, and the average stress distribution value of von Mises was performed on the gear root atmosphere. The structural safety of the 2-speed planetary gear reducer was verified through FM structural analysis. The natural frequency was calculated by applying the specifications of the planetary gears of the 2-speed gearbox, and the critical speed of resonance was calculated by calculating the natural frequency and the transmission error of the engaged gear pair. As a result of analyzing the critical speed, since it is formed higher than the actual operating speed range, it is considered safe because there is no resonance problem due to the suggested specifications of the planetary gears of the 2-speed shift reduction.

• Journal of Software Assessment and Valuation
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• v.8 no.2
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• pp.13-27
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• 2012

This paper presents a tree-pattern based code-clone detector as CCR(Code Clone Ransacker) that finds all clusterd dulpicate pattern by comparing all pair of subtrees in the programs. The pattern included in its entirely in another pattern is ignored since only the largest duplicate patterns are interesed. Evaluation of CCR is high precision and recall. The previous tree-pattern based code-clone detectors are known to have good precision and recall because of comparing program structure. CCR is still high precision and the maximum 5 times higher recall than Asta and about 1.9 times than CloneDigger. The tool also include the majority of Bellon's reference corpus.

• The Journal of Economics, Marketing and Management
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• v.12 no.4
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• pp.27-36
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• 2024

Purpose: The paper analyzes for detecting unexpected shocks such as global financial crisis and COVID-19 pandemic, and contagion between countries by capturing in the mean-shift, variance-covariance-shift, and skewness-coskewness-shift parameters of interest rates. Research design, data and methodology: A flexible multivariate model of interest rates is provided by allowing for regime switching and a joint skewed normal distribution. The model is applying to the structural breaks of crisis and contagion between the US and the selected global bond markets during the global financial crisis and COVID-19 pandemic, respectively. Inspection of the moment statistics weakly suggests a flight to safety to the US during the global financial crisis and to Canada during the COVID-19 pandemic. Results: The results indicate that risk averse investors had a higher risk appetite for the US and Canada assets during the crisis regimes, compared to their counterparts. Conclusions: The results show that coskewness contagion dominates correlation contagion, and coskewness contagion is significant for the Korea and Japan-US pairs for the global financial crisis and the Euro-US pair for the COVID-19 pandemic. All channels of structural breaks of crisis and contagion are significant when considered jointly, reinforcing the need to consider contagion and structural breaks during crises in a multivariate setting.

• 대한예방의학회:학술대회논문집
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• 1999.10a
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• pp.1-15
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• 1999

In a case-control study to evaluate the factors involved in the development of hepatocellular carcinoma, polymorphisms of the p53 gene were compared in 68 cases mostly infected with hepatitis C virus (HCV) and 68 controls matched for sex and age: DNA from peripheral blood leukocytes was analyzed by the polymerase chain reaction-single strand conformation polymorphism method and direct sequencing. Polymorphisms analyzed were those in exon 4 (CCC vs. CGC, Pro vs. Arg at codon 72, Al allele vs. A2 allele), intron 2 (C vs. G at nucleotide 38, Al vs. A2), intron 3 (C vs. A at nucleotide 65, Al vs. A2; absence and presence of 16 base pair repeat at nucleotides 24 to 39, Al vs. A2), intron 6 (A vs. G at nucleotide 62, Al vs. A2) and intron 7 (C and T vs. T and G at nucleotides 72 and 92, Al vs. A2). A significantly higher frequency of the allele for CCC (Pro, Al) at codon 72 of exon 4 was found in cases (39%) than in controls (26%) (p<0.05). Highly significant linkage of the polymorphisms in exon 4, intron 2, intron 3 and intron 7, and between the intron 3-16 bp duplication and polymorphism in intron 6 also was found. Matched Fair analysis showed significantly higher frequencies of certain haplotypes (1-1-1-1-2-2 or 1-1-2-1-2-1 for exon 4, intron 2, intron 3, the intron 3-16 bp duplication, intron 6 and intron 7) in cases than in controls (p=0.014, OR=2.27, 95% CI= 1.08-5.12). No preference of specific p53 polymorphisms for specific HCV genotype was detected. These findings suggest that in hepatocarcinogenesis mainly due to HCV infection, genetic factors may be involved and that genetic markers can serve as predictors of a high-risk group for hepatocarcinogenesis.

• Fashion & Textile Research Journal
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• v.19 no.5
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• pp.653-660
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• 2017

Recently, consumers' evaluation and purchase of online design has been increasing due to the popularization of designing through personal computers, but there has not been enough studies on consumers' brain wave responses depending on the change of PC monitor's color. Therefore, this study investigated how brain waves changed when different background colors with gray patterns were presented through PC monitors. Six background colors with same tone of slightly low saturation were selected, including ivory, yellow, pink, green, blue and pure white as a base color. The brightness and characteristics of color used were analyzed using the luminance meter and color scales. Brain wave was measured by EEG measurement equipment. Brain wave measurement was carried out with 9 subjects at 6 points: F3, F4, T3, T4, O1, and O2. Stimuli were shown for 15 seconds each and black screens were displayed for 15 seconds between each stimulus. As results, the brain waves at O1 responded sensitively by different background colors, followed by F4 and T4. Brain index such as 'RT', 'RA', 'RG', 'RSA', and 'RAHB' showed significant differences depending on the background color at O1, whereas 'RST' differed at F4. Yellow and blue backgrounds pair was the only stimuli that showed significant differences in six brain indices mentioned. Yellow background had higher value of 'RG' at O1 and higher 'RST' at F4, indicating yellow background enhanced concentration. Blue background activated 'RT', 'RA', 'RSA', 'RAHB' at O1, meaning blue background induced calm and stable state.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.4
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• pp.173-178
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• 1980

Cercaria larvae of Bacciger harengulae which is parasitic to Meretrix lusoria, rapes japonica and Solen strictus were studied in terms of their morphology and incidence of infection rate. The host bivalves were collected from Naechodo, Okgu-gun during the Period from January to November in 1980. The tail of the cercaria bears 27 pairs of tufts of setae, the tufts being composed of 6 fine rays. Oral sucker, intestine, ventral sucker and a pair of testes are distinctive. The excretory duct bears numerous granules of various size, and the flame-cell arrangement is represented by a formula 2[(3+3)+(3+3)]=24. The cercaria is somewhat similar to the previously known Cercaria pectinata . It is however conformed that present cercaria belongs to Bacciger harengulae. Infection rate showed seasonal variation and host selectivity. Higher infections were observed in Solen strictus, and lower in Meretrix lusoria. Generally, the larger bivalves over 2-3 years old showed the higher infection rate.