• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.4
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• pp.29-35
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• 2008

In this paper, a new guidance law to reduce sensitivity to the initial heading errors is proposed. In order for shaping the input weights over the flight, we introduce the distribution functions expressed in terms of time-to-go and its inverse term. By applying the optimal control theory with the synthesized weights, the homing guidance law is derived. Also the characteristics of the proposed law are examined. Various computer simulations show the good performance of the proposed guidance.

• Journal of Korea Multimedia Society
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• v.19 no.8
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• pp.1386-1394
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• 2016

Pyramid fusion usually adjusts the Laplacian weights of pixels of the input images by evaluating predefined criteria. This has advantages that it can selectively express intense color and enhance the contrast when applied to HDR exposure fusion. But it may cause noise because the weights are determined by pixel importance without considering the interdependent pixel relationship that constitutes a scene. This paper proposes a fusion method using simple weight criteria generated from the gray pixel values, which is expected to preserve the interdependent relationship and improve execution speed. In order to evaluate the performance of the proposed method we examine a homogeneity measure, H and compare the execution time for both methods. The proposed method is found to be more advantageous with respect to homogeneity and execution speed.

• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1337-1340
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• 2001

The bulk photopolymerization of methyl methacrylate (MMA) with para-substituted phenylsilanes such as F-C6H4SiH3 (1), H3C-C6H4SiH3 (2), and H3CO-C6H4SiH3 (3) was performed to produce poly(MMA)s containing the respective silyl moiety as an end group. For all the hydrosilanes, the polymerization yields and the polymer molecular weights decreased, whereas the TGA residue yields and the relative intensities of Si-H IR stretching bands increased as the relative silane concentration over MMA increased. The polymerization yields and polymer molecular weights of MMA with 1-3 increased in the order of 3 < 1 < 2. These hydrosilanes influence significantly upon the photopolymerization of MMA as both chain-initiation and chain-transfer agents.

• Journal of Korea Multimedia Society
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• v.24 no.11
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• pp.1461-1471
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• 2021

This paper presents a light exposure correction algorithm for less pleasant images, acquired with a light metering failure. Since conventional tone mapping and gamma correction methods adopt a function mapping with the same range of input and output, the results are pleasurable for almost symmetric distributions to their intensity average. However, their corrections gave insufficient outputs for asymmetric cases at either bright or dark regions. Also, histogram modification approaches show good results on varied pattern images, but these generate unintentional noises at flat regions because of the compulsive shift of the intensity distribution. Therefore, in order to sufficient corrections for both bright and dark areas, the proposed algorithm calculates the gamma coefficients using primary parameters extracted from the global distribution. And the fusion weights are adaptively determined with complementary parameters, considering the classification information of a binary segmentation. As the result, the proposed algorithm can obtain a good output about both the symmetric and the asymmetric distribution images even with severe exposure values.

• Journal of the Korea Society of Computer and Information
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• v.23 no.12
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• pp.219-226
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• 2018

Collaborative filtering has been most popular approach to recommend items in online recommender systems. However, collaborative filtering is known to suffer from data sparsity problem. As a simple way to overcome this problem in literature, Jaccard index has been adopted to combine with the existing similarity measures. We analyze performance of such combination in various data environments. We also find optimal weights of factors in the combination using a genetic algorithm to formulate a similarity measure. Furthermore, optimal weights are searched for each user independently, in order to reflect each user's different rating behavior. Performance of the resulting personalized similarity measure is examined using two datasets with different data characteristics. It presents overall superiority to previous measures in terms of recommendation and prediction qualities regardless of the characteristics of the data environment.

• Asian Journal of Innovation and Policy
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• v.8 no.1
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• pp.73-96
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• 2019

This study suggests a new approach for identifying core robot tech-nologies based on technological cross-impact. Specifically, the approach applies data mining techniques and multi-criteria decision-making methods to the co-classification information of registered patents on the robots. First, a cross-impact matrix is constructed with the confidence values by applying association rule mining (ARM) to the co-classification information of patents. Analytic network process (ANP) is applied to the co-classification frequency matrix for deriving weights of each robot technology. Then, a technique for order performance by similarity to ideal solution (TOPSIS) is employed to the derived cross-impact matrix and weights for identifying core robot technologies from the overall cross-impact perspective. It is expected that the proposed approach could help robot technology managers to formulate strategy and policy for technology planning of robot area.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.1
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• pp.25-31
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• 2018

In this study, the differences of holding power according to the shape and weight distribution of concrete weight used in shellfish shell fishery were investigated through the experiments. To investigate the differences in shape, five bar-shaped concrete weights with the same length and different cross-sectional shapes were produced. The sectional shape of each weight was square, triangle, circle, small cross, and large cross (SQ, TR, CI, CR-S, CR-L). Ten rectangular parallelepiped weights with different bottom area and cross-sectional area were produced. To investigate the differences by the weight distribution, the holding power on the square model (SQ) with six 50 g weights at different positions was investigated. All the holding power was obtained by measuring the tensile force generated when the concrete weight was pulled at a constant speed on the sand. As a result, there were no differences in holding power between the ten rectangular weights. However, the experiment on weights with different cross-sectional shapes showed differences in holding power. The holding power was higher in the order of CR-L > CR-S > CI > TR > SQ. In the weight distribution test, the holding power was higher as the front side of the weight was heavier. Generally, the frictional force is the same even if the shape is different, when two objects have the same value in the weight and the roughness. On the other hand, it seems to have a large impact when the shape of the bottom is deformed in the course of pulling the object. Particularly, the larger the degree of protrusion like cruciform weights, the more the holding power increased while deeply digging the bottom. It is also likely that the holding power increases as the front weight increases.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.2
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• pp.444-452
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• 2007

Acupuncture treatment cures disease by regulating the functional excessiveness or deficiency which occurs in the meridian and visceral organs, and by letting stagnated Qi and Blood flow through the whole body and then controlling Qi. Whether or not to have Qi feeling is the main factor needed to manifest the efficacy of acupuncture. So it needs the very stimulus to make Qi felt rather than the simple stimulus. In order to have Qi feeling, it needs to acupuncture a patient according to patient's thinness or fatness, constitution, richness or poverty and age. And also it needs to vary the way to acupuncture a patient according to meridian, kinds of pulse, degrees of disease, new or old diseases, seasons with a disease and local areas of disease. In order to ascertain that it is important for the quality and quantity of acupuncture stimulus and the state of feeling acupuncture to get the efficacy of acupuncture, the experiment was planned to confirm whether the form and Qi of subject has different result according to the stimulated duration and depth. On the basis of the report that acupuncture on derma, when using electroacupuncture at Zusanli(ST 36) which denotes small intestinal motility, is more efficient than full depth acupuncture, I got the following result, after I observed whether the stimulated duration and depth give different efficacy according to the sex and weights of rat in experiment. The increased effects of small intestinal motility by electroacupuncture on Zusanli(ST 36) appeared after stimulating full depth for thirty minutes without distinction of sex and weights. This significant change was observed only in the female experimental group when I distinguished the sex. The small interstinal motility in rats by electroacupuncture at zusanli(ST 36) decreased in the 10 minutes' stimulated group and 30 minutes' stimulated group by duration on the one hand, and derma-deep stimulated group and full depth stimulated group by the depth of stimulus on the other hand, as the weights increased. This result shows that the duration and depth of acupuncture depends on the differences of acupuncture points, sex of the experimental animals, ages, and, weights. And the further study on the experimental and clinical differences and sextual differences need to be continued on.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.10
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• pp.446-452
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• 2002

For most of pattern recognition applications, it is required to correctly recognize patterns even if they have translation variations. In this paper, to achieve the goal of translation invariant pattern recognition, we propose a new generalized translation invariant second-order neural network using a constraint on the weights. The weight constraint is implemented using generalized translation invariant features which are accumulated sums of pixel combinations. Simulation results will be given to demonstrate that the proposed second-order neural network has the generalized translation invariant property.

• Journal of Information Science Theory and Practice
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• v.4 no.1
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• pp.21-29
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• 2016

Given the difference in research performance in various scientific fields, this study aims to weight and valuate current indicators used for evaluation of scientific productions (publications), in order to adjust these indicators in comparison to each other and make possible a more precise evaluation of scientific productions. This is a scientometrics study using documentary, evaluative, and survey techniques. The statistical population consisted of 106 top Iranian researchers, scientists, and scientific and research managers. Then their research résumé information was gathered and analyzed based on research questions. In order to compare values, the data gathered from research production performance of the population was weighted using Shannon entropy method. Also, the weights of each scientific production importance according to expert opinions (extracted from other works) was analyzed and after adjustment the final weight of each scientific production was determined. A pairwise matrix was used in order to determine the ratios. According to the results, in the area of engineering sciences, patents (0.142) in the area of science, international articles (0.074) in the area of humanities and social sciences, books (0.174), and in the area of medical sciences, international articles (0.111) had the highest weight compared to other information formats. By dividing the weights for each type of publication, the value of each scientific production compared to other scientific productions in the same field and productions of other fields was calculated. Validation of the results in the studied population resulted in very high credibility for all investigated indicators in all four fields. By using these values and normalized ratios of publication indicators it is possible to achieve precise and adjusted results, making it possible to feasibly use these results in realistic policy making.