• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7667-7671
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• 2015

Recently, Zinc coating is often used with environment friendly features and high performance. Generally The coating temperature is one of main factors for determining coating thickness and coating ability, so the optimal coating temperature is strongly required. In this paper, the thermo-flow simulation considering the air flow inside the coating rooms for analyzing the temperature distributions of Zinc spray coating room was performed. Two spray coating rooms, preheating room and drying room were all modeled by SolidWorks program and the temperature distributions were analyzed by Flow simulation program. The analysis results were verified with the measured data by thermal image camera. The characteristics of temperature distributions of the first spray room and the second spray room were understood and the results showed that the temperatures of two spray coating room were low compared with the target temperature $25^{\circ}C$. To the exclusion of heater addition, the simulation with all the same conditions exclusive the exhaust fan was performed, which showed that the temperatures of the first and the second spray rooms increased by $6.2^{\circ}C$ and $5.8^{\circ}C$. This analysis can be applicable for designing a new spray coating room for improving performance.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.3
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• pp.649-660
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• 2017

In electronic warfare, the pulse amplitude, one of information of a pulse signal emitted by an enemy, is used for estimating distance from the source and for deinterleaving mixed source signals. An estimate of pulse amplitude is conventionally determined as the maximum magnitude of a Fourier transformed signal within its pulse width which is estimated pre-step in an electronic warfare receiver. However, when frequency modulated signals are received, it is difficult to estimate their pulse amplitudes with this conventional method because the energy of signals is dispersed in frequency domain. In order to overcome this limitation, this paper proposes an enhanced pulse amplitude estimation method which calculates the average power of the received pulse signal in time domain and removes the noise power of the receiver. Simulation results show that even in case the frequency modulated signal is received, the proposed method has the same performance as estimating the pulse amplitude when unmodulated signal is received. In addition, the proposed method is shown to be more robust to an estimation error of pulse width, which affects the estimation performance of pulse amplitude, than the conventional method.

• Journal of Intelligence and Information Systems
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• v.25 no.4
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• pp.89-103
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• 2019

Recently, various approaches to recommendation systems have been studied in terms of the quality of recommendation system. A recommender system basically aims to provide personalized recommendations to users for specific items. Most of these systems always recommend the most relevant items of users or items. Traditionally, the evaluation of recommender system quality has focused on the various predictive accuracy metrics of these. However, recommender system must be not only accurate but also useful to users. User satisfaction with recommender systems as an evaluation criterion of recommender system is related not only to how accurately the system recommends but also to how much it supports the user's decision making. In particular, highly serendipitous recommendation would help a user to find a surprising and interesting item. Serendipity in this study is defined as a measure of the extent to which the recommended items are both attractive and surprising to the users. Therefore, this paper proposes an application of serendipity measure to recommender systems to evaluate the performance of recommender systems in terms of recommendation system quality. In this study we define relevant or attractive unexpectedness as serendipity measure for assessing recommendation systems. That is, serendipity measure is evaluated as the measure indicating how the recommender system can find unexpected and useful items for users. Our experimental results show that highly serendipitous recommendation such as item-based collaborative filtering method has better performance than the other recommendations, i.e. user-based collaborative filtering method in terms of recommendation system quality.

• Korean Journal of Applied Biomechanics
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• v.18 no.3
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• pp.61-69
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• 2008

The purpose of this study is to examine the success or failure on the balance beam in element group requirements posture which is bending salto side-ward tucked through kinetic analysis. The national team players were participated. The goal was to present training methods to coaches and athletes so as to provide scientifically useful information. The results from this study were summarized as below. When the performance was successful, the features of the body's center of gravity during the side somersault motion showed to spread from the center of the balance beam and the center of the gravity moved to the direction of the body's rotation. In the spring sections - event2 and 3, when the performance was successful, up/down fluctuation became more wider and increased air time. It supported the result that the projecting variable was higher than in failure trial. In addition, the right side hip joint angles and speed, and angular velocity as jumping up for a leap were larger than in failure trial. Those variables showed the optimal conditions for a leap. By increasing the speed of the upper limb from the shoulder and the speed of the shoulder joint angular velocity, the momentum was increased. Especially the right side shoulder joint angular velocity increased dramatically because the right leg was held. As to the side somersault motion, the angular momentum of successful trial with respect to x-axis was bigger than failed trial. It indicated that the increasing angular momentum with respect to x-axis was an important factor in flying motion. Besides, as to side somersault, the appropriate proportion of angular momentum with respect to y-axis and z-axis was a key to successful trails.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.3
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• pp.463-469
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• 2009

We performed the experimental study on the control of suspended dust in a cement packaging process for various ventilation systems. To effectively remove the dust generated in the cement packaging process, three different kinds of ventilation system, such as local exhaust ventilation, electrostatic scrubber, and local air supply system, were adopted. Dust concentrations in the packaging process were measured with the variation of the airflow rate of the ventilation systems and then their ventilation performance were evaluated. From the results, we knew that the ventilation performance was the best when the local exhaust ventilation and the electrostatic scrubber were simultaneously operated in the packaging process. In the electrostatic scrubber system, the effect of the airflow rate on the indoor dust removal efficiency was negligible so hat he system ust be operated at $2,700m^3/h$ for saving power consumption.

• Journal of the Korean Institute of Intelligent Systems
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• v.26 no.6
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• pp.471-476
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• 2016

In this paper, recognition system for continuous human action is explained by using motion history image and histogram of oriented gradient with spotter model based on depth information, and the spotter model which performs action spotting is proposed to improve recognition performance in the recognition system. The steps of this system are composed of pre-processing, human action and spotter modeling and continuous human action recognition. In pre-processing process, Depth-MHI-HOG is used to extract space-time template-based features after image segmentation, and human action and spotter modeling generates sequence by using the extracted feature. Human action models which are appropriate for each of defined action and a proposed spotter model are created by using these generated sequences and the hidden markov model. Continuous human action recognition performs action spotting to segment meaningful action and meaningless action by the spotter model in continuous action sequence, and continuously recognizes human action comparing probability values of model for meaningful action sequence. Experimental results demonstrate that the proposed model efficiently improves recognition performance in continuous action recognition system.

• (The) Research of the performance art and culture
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• no.32
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• pp.7-30
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• 2016

The inter­relationship of Korea southeast region community related to a mask dramas in depth. The Folk mask dramas are, for traditional community members to live well and enjoy cultural practices in society. Even if a mask drama would be performed in the 21st century, it would be the one of traditional society. It shows the life of traditional society and proposes the issue of traditional society. The thing is handed down well with technology of a mask drama assigned as intangible cultural asset. The Korea southeast region, Kyongsang Provinces, or Yeongnam area has been handed down several kind of mask dramas. These are Byeolsingut Talnori with religious, the Ogwangdae of wandering play team, the Ogwangdae of local residents, and the Dulnorum of local residents. The mask dramas of Korea southeast region are specified as intangible cultural asset, many traditional mask play were restored. The restoring is imitation. These things are difficult to assigned as the intangible cultural asset. But though it is the imitation of the mask dramas, it is culture phenomenon. So we need to make the fostering system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.814-824
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• 2018

This study was conducted to investigate VFA, monosaccharides and metabolites in rumen fluid according to feeding methods. Three castrated Hanwoo steers were used to the $3{\times}3$ Latin square design, 10 day for the diet adaptation period. VFA and monosaccharides which were not detected by HPLC and HPAEC however, those were detected by $^1H-NMR$. Among the metabolites measured by $^1H-NMR$ carbohydrate metabolites, pyruvate was detected only in the rumen fluid before feeding and succinate was detected before and after feeding rumen fluid. In amino acid total 9 metabolites were detected. In lipid metabolites, ethylene glycol was significantly higher (P<0.05) in before feeding Con group. In aliphatic acylic metabolite, trimethylamine N-oxide was no significant difference observed compare to Con group. In this study, many metabolites were observed in the rumen fluid by $^1H-NMR$, and it confirmed that rumen metabolic products were changed by feeding methods.

• Korean Journal of Remote Sensing
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• v.36 no.6_2
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• pp.1615-1627
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• 2020

The purpose of this study is to compare and analyze the performance of KOMPSAT-3 Digital Surface Model (DSM) made in overseas testbed area. To that end, we collected the KOMPSAT-3 in-track stereo image taken in San Francisco, the U.S. The stereo geometry elements (B/H, converse angle, etc.) of the stereo image taken were all found to be in the stable range. By applying precise sensor modeling using Ground Control Point (GCP) and DSM automatic generation technique, DSM with 1 m resolution was produced. Reference materials for evaluation and calibration are ground points with accuracy within 0.01 m from Compass Data Inc., 1 m resolution Elevation 1-DSM produced by Airbus. The precision sensor modeling accuracy of KOMPSAT-3 was within 0.5 m (RMSE) in horizontal and vertical directions. When the difference map was written between the generated DSM and the reference DSM, the mean and standard deviation were 0.61 m and 5.25 m respectively, but in some areas, they showed a large difference of more than 100 m. These areas appeared mainly in closed areas where high-rise buildings were concentrated. If KOMPSAT-3 tri-stereo images are used and various post-processing techniques are developed, it will be possible to produce DSM with more improved quality.

• Journal of Digital Convergence
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• v.19 no.5
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• pp.461-468
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• 2021

The purpose of this study is to collect official records of the 2019 Men's and Women's Handball World Championships to identify important shooting variables that determine the team's record of winning or losing. After collecting 192 games of men's and women's national teams from 24 countries and verifying the difference in competition records according to the winning and losing groups, the decision tree method, one of the data mining techniques, is analyzed. According to the analysis, the 9m shooting success rate and Near shooting success rate were the most important factors for both men and women. Men win 83.3% if the 9m shooting success rate is 32.5% or higher and the Near shooting success rate is 67.5%, and women win 75% if the 9m shooting success rate is 75% or more and the Near shooting success rate is 51%. Also, the women's yellow cards are considered important variables that determine victory or defeat. In conclusion, both men and women were able to identify the factors of winning and losing decision shooting, but follow-up studies are needed considering the relativity of various record variables and performance in future handball.