• Journal of Convergence for Information Technology
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• v.10 no.6
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• pp.1-7
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• 2020

The demand on the underwater communications is extremely increasing in searching for underwater resources, marine expedition, or environmental researches, yet there are many problems with the wireless communications because of the characteristics of the underwater environments. Especially, with the underwater wireless networks, there happen inevitable delay time and spacial inequality due to the distances between the nodes. To solve these problems, this paper suggests a new solution based on ALOHA-Q. The suggested method use random NAV value. and Environments take reward through communications success or fail. After then, The environments setting NAV value from reward. This model minimizes usage of energy and computing resources under the underwater wireless networks, and learns and setting NAV values through intense learning. The results of the simulations show that NAV values can be environmentally adopted and select best value to the circumstances, so the problems which are unnecessary delay times and spacial inequality can be solved. Result of simulations, NAV time decreasing 17.5% compared with original NAV.

• Safety and Health at Work
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• v.8 no.2
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• pp.175-182
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• 2017

Background: With the recent rapid industrialization, occupational safety and health (OSH) has become an important issue in all industrial and human activities. However, incidents of injuries and fatality rates in the Ghanaian industry sector continue to increase. Despite this increase, there is no evidence regarding the element of OSH management in transport activities in Ghanaian industries. Thus, this study aims to examine the perceptions regarding the importance of safety and health in work-related transport activities in Ghanaian industries. Methods: A survey data collection technique was used to gather information on best safety practices over a 5-month period. We randomly selected 298 respondents from industries to answer structured questionnaires. The respondents included drivers, transport managers, and safety engineers. Standard multiple regression model and Pearson product-movement correlation were used to performed the analysis. Results: The result shows that for interventions to improve safety and health, concentration has been on drivers' safety practice with less attention to safe driving environments and vehicle usage. Additionally, the respondents are aware of the importance of OSH in transport activities, but the level of integration does not measure up to the standard to reduce operational accidents and injuries. Finally, strong commitment to changing unsafe practices at all levels of operations appears to be the effective way to improve safety situations. Conclusion: OSH culture is not fully complied in industries transport activities. This study, therefore, supports the use of safety seminars and training sessions for industry workers responsible for transport operations for better integration of safety standards.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.1 s.139
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• pp.167-176
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• 2005

The purpose of this study were to examine the relationship with respect to internet addiction and internet shopping addiction among internet fashion shoppers, and to find if internet addiction had mediating effects on internet shopping addictive buying. 550 females and males who had purchased fashion goods were used for the survey. For data analysis, descriptive statistics and Amos 5.0 were used. As the results, approximately $32.7\%\;and\;3.82\%$ of subjects were revealed as light internet addictive shoppers and heavy internet addictive shoppers. Also, $14.0\%$ of the internet shoppers in this study were found to have internet shopping addictive tendencies. Psychological factors such as self-esteem, impulsiveness, materialism, and compensatory buying were directly related to internet shopping addiction as well as to internet addiction. Internet-related factors such as flow, skill and usage time also were directly related to internet addiction, but not to internet shopping addictive buying. That is, internet addiction had a mediator effect between psychological factors and internet shopping addictive buying. Also, internet shopping variables such as buying frequency and shopping mall visit frequency were related to internet shopping addiction. Finally, internet addiction was directly related to internet shopping addiction. Based on these results, fashion marketing strategies and implications regarding internet shopping addiction were suggested.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.216-216
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• 1999

The usage of a stationary plasma thruster (SPT) ion source, invented previously for space application in Russia, in experiments with surface modifications and film deposition systems is reported here. Plasma in the SPT is formed and accelerated in electric discharge taking place in the crossed axial electric and radial magnetic fields. Brief description of the construction of specific model of SPT used in the experiments is presented. With gas flow rate 39ml/min, ion current distributions at several distances from the source are obtained. These was equal to 1~3 mA/$\textrm{cm}^2$ within an ion beam ejection angle of $\pm$20$^{\circ}$with discharge voltage 160V for Ar as a working gas. Such an extremely high ion current density allows us to obtain the Ti metal films with deposition rate of $\AA$/sec by sputtering of Ti target. It is shown a possibility of using of reactive gases in SPT (O2 and N2) along with high purity inert gases used for cathode to prevent the latter contamination. It is shown the SPT can be operated at the discharge and accelerating boltages up to 600V. The results of presented experiments show high promises of the SPT in sputtering and surface modification systems for deposition of oxide thin films on Si or polymer substrates for semiconductor devices, optical coatings and metal corrosion barrier layers. Also, we have been tried to establish in application of the modeling expertise gained in electric and ionic propulsion to permit numerical simulation of additional processing systems. In this mechanism, it will be compared with conventional DC sputtering for film microstructure, chemical composition and crystallographic considerations.

• Journal of fish pathology
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• v.15 no.2
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• pp.49-56
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• 2002

Effects of Temperature on the Pharmacokinetics of norfloxecin (NFX) were studied in the cultured carp,Cyprinus carpio, and cel, Anguilla japonica, using high performance liquid chromatography (HPLC) originally developed for quinolone determination in livesrocks. Pharmacokinetics of NFX was apparently affected by ambiem water temperature. In a two-compaament model for carp after oral dosage of 20 mg/K01 at $13^{\circ}C$ and $23^{\circ}C$ and 5.20/hr, respectively. In carp the $K_{\iota\nu}$, $T_{max}$and $C_{max}$ for carp at $13^{\circ}C$ were 13.30/hr, 17.44 ${\mu}g$/$m\ell$ and 7.00 ${\mu}g$/$m\ell$, respectively. The" correspoeding values at $23^{\circ}C$ were 3.93/hr, 15.40 ${\mu}g$/$m\ell$ and 9.44 ${\mu}g$/$m\ell$, respectively. The AUC and T were 355.66 ${\mu}g$ hr/$m\ell$, and 12.70 hr at $13^{\circ}C$ and 417,24 ${\mu}g$ hr/$m\ell$ and 13.86 hrs at $23^{\circ}C$, respectively. Similar trends were revealed in the NFX pharmacokinetics of eel kept under the two water temperature regimes aftee oral NFX dosage of 20 mg/kg. These pharmacokinetkal results have some implication in the optimal usage of recently introduced antibacterials in farmed fish, which were originally adapted for poultry and mammalian species.

• The Journal of Korean Association of Computer Education
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• v.14 no.4
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• pp.11-20
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• 2011

Recently, the interests of mobile GIS(Geographic Information System) technology is increasing with the spread of wireless network, the improvement of mobile device's performances and the growth of demands about mobile services. If we refer mobile GIS system classified as 3rd generation with the success of Web 2.0, it is suggested that supplies of information from the server side couldn't enhance users' participations and the usage of service. In this study, we suggested the model of GIS 2.0 application based on Google map for Android smart-phones, which users could make, save and share information using photos and text by themselves. We were able to grasp the expectation of GIS 2.0 by expert assessment of this application and got to the core of conditions and implications for the success of GIS 2.0.

• Journal of Ecology and Environment
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• v.38 no.1
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• pp.95-107
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• 2015

Because an ecological community consists of diverse species that vary nonlinearly with environmental variability, its dynamics are complex and difficult to analyze. To investigate temporal variations of benthic macroinvertebrate community, we used the community data that were collected at the sampling site in Baenae Stream near Busan, Korea, which is a clean stream with minimum pollution, from July 2006 to July 2013. First, we used a self-organizing map (SOM) to heuristically derive the states that characterizes the biotic condition of the benthic macroinvertebrate communities in forms of time series data. Next, we applied the hidden Markov model (HMM) to fine-tune the states objectively and to obtain the transition probabilities between the states and the emission probabilities that show the connection of the states with observable events such as the number of species, the diversity measured by Shannon entropy, and the biological water quality index (BMWP). While the number of species apparently addressed the state of the community, the diversity reflected the state changes after the HMM training along with seasonal variations in cyclic manners. The BMWP showed clear characterization of events that correspond to the different states based on the emission probabilities. The environmental factors such as temperature and precipitation also indicated the seasonal and cyclic changes according to the HMM. Though the usage of the HMM alone can guarantee the convergence of the training or the precision of the derived states based on field data in this study, the derivation of the states by the SOM that followed the fine-tuning by the HMM well elucidated the states of the community and could serve as an alternative reference system to reveal the ecological structures in stream communities.

• Journal of Broadcast Engineering
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• v.25 no.4
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• pp.569-575
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• 2020

The serial arc is one of factors causing electrical fires. Over past decades, various researches have been carried out to detect arc occurrences. Even though frequency analysis, wavelet, and statistical features have been used, additional steps such as transformation and feature extraction are required. On the contrary, deep learning models directly use the raw data without any feature extraction processes. Therefore, the usage of time-domain data is preferred, but the performance is not satisfactory. To solve this problem, subsequent 1-D signals are transformed into 2-D data that can feed into a convolutional neural network (CNN). Experiments validated that CNN model outperforms deep neural network (DNN) by the classification accuracy of 8.6%. In addition, data augmentation is utilized, resulting in the accuracy improvement by 14%.

• Journal of Advanced Navigation Technology
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• v.18 no.6
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• pp.600-608
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• 2014

In this paper, CABAC H/W module is developed using co-design method. After entire H.264/AVC encoder was developed with C using reference SW(JM), CABAC H/W IP is developed as a block in H.264/AVC encoder. Context modeller of CABAC is included on the hardware to update the changed value during binary encoding, which enables the efficient usage of memory and the efficient design of I/O stream. Hardware IP is co-operated with the reference software JM of H.264/AVC, and executed on Virtex-4 FX60 FPGA on ML410 board. Functional simulation is done using Modelsim. Compared with existing H/W module of CABAC with register-level design, the development time is reduced greatly and software engineer can design H/W module more easily. As a result, the used amount of slice in CABAC is less than 1/3 of that of CAVLC module. The proposed co-design method is useful to provide hardware accelerator in need of speed-up of high efficient video encoder in embedded system.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.4
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• pp.401-407
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• 2000

Modern microprocessors exploit instruction-level parallel processing to increase the performance. Especially VLIW processors supported by the parallelizing compiler are used more and more in specific applications such as high-end DSP and graphic processing. Bus-based VLIW architecture was proposed for these specific applications and it was designed to reduce the overhead of forwarding unit and the instruction width. In this paper, a optimizing scheduling compiler developed for the proposed bus-based VLIW processor is introduced. First, the method to model interconnections between buses and resource usage patterns is described. Then, on the basis of the modeling, machine-dependent optimization techniques such as bus-to-register promotion, copy coalescing and operand substitution were implemented. Optimization techniques for general-purpose VLIW microprocessors such as selective scheduling and enhanced pipelining scheduling(EPS) were also implemented. The experiment result shows about 20% performance gain for multimedia application benchmarks.