• Journal of Korea Multimedia Society
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• v.4 no.5
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• pp.455-464
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• 2001

For future multimedia services, one of the most crucial issues is building an access network that can accommodate multimedia services in subscriber network. The VB5.2 interface of B-ISDN located between an access network and a service node allows dynamic allocation and release of ATM resources. The SG 13 of ITU-T is standardizing the B-BCC protocol, which is sequentially interworked with signaling protocols in the service node. To minimize a connection setup delay of the sequential interworking mode, we proposed the parallel interworking model in which the SN executes simultaneously the connection control protocol of VB5.2 interface and signaling protocol. We simulate two interworking models in terms of a connection setup delay and a completion ratio. The results of simulation show that our proposed parallel interworking model for the VB5.2 interface reduces the setup delay and has the similar completion ratio compared to the sequential interworking model. however, the connection setup delay of parallel interworking model becomes about seven tenths of that of the sequential interworking model and the improvement become larger as the arrival rate increased.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.75-82
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• 2005

Pyrolysis of biomass is one of the promising methods to obtain energy and valuable chemical stocks. Fast pyrolysis of Q. acutissima and L. letolepis has been carried out in a bubbling fluidized bed reactor to determine the optimum operating conditions of the pyrolyzer. Effects of reaction temperature, Uo/Umf, L/D ratio, and feed rate have been determined and the optimum conditions are as follows: $T\;=\;400^{\circ}C,\;U_o/U_{mf}\;=\;3.0,\;L/D\;=\;2.0$. Maximum yield of bio-oil was about 55% and the main compositions were carbohydrates, guaiacols, furans, phenols, and syringols. Product gas was consists of CO, $CO_2$, light hydrocarbons and the measured gas yield using the compositions agreed with the calculated value.

• Food Science and Preservation
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• v.16 no.2
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• pp.299-303
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• 2009

To explore the preservation parameters of a prototype anti-inflammatory drink containing a Helianthus annuus seed extract, we first examined sweetness, pH and color changes, and temperature effects during preservation. Over 25 days, pH rose slightly from 3.50 to 3.65. Small color changes in L, a, and b values occurred on prolonged storage. Temperature most affected storage properties, which differed considerably at $10^{\circ}C$ and $40^{\circ}C$. Microbiological safety tests showed that the prototype drink was safe; neither general bacterial contamination nor Escherichia coli growth occurred. We concluded that the prototype drink was biologically and microbiologically safe on preservation.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.303-307
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• 2009

Secondary flow losses can be as high as $30{\sim}50%$ of the total aerodynamic losses generated in the cascade of a turbine. Therefore, these are important part for improving a turbine efficiency. As well, many studies have been performed to decrease the secondary flow losses. The present study deals with the leading edge fences on a wing-body to decrease a horseshoe vortex, one of the factors to generate the secondary flow losses, and optimizes the shape of leading-edge fence with the shape factors, such as the installed height, length, width, and thickness of the fence as the design variables. The study was investigated using $FLUENT^{TM}$ and $iSIGHT^{TM}$. Total pressure loss coefficient was improved about 7.5 % than the baseline case.

• Journal of the Korean Electrochemical Society
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• v.15 no.4
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• pp.256-263
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• 2012

This study was performed to investigate the separation of cesium cations by using an electrochemical ion exchanger of nickel hexacyanoferrate($KNiFe(CN)_6$) film electrode. Potential, current, and charge passing through the cyclic voltammograms were measured in singular and binary solutions of 1.0M $NaNO_3$ and 1.0M $CsNO_3$. Before and after each experiment, the structural morphology and atomic composition of $KNiFe(CN)_6$ were analyzed by SEM and EDS, respectively. The ion selectivity of $KNiFe(CN)_6$ was also observed by the voltammograms and atomic compositions measured in the solution alternated between sodium and cesium. As the result of this study, it was found that the electrically switched $KNiFe(CN)_6$ ion exchanger had the significant advantage of 40 times or longer durability than conventional organic or inorganic ion exchanger. It was also shown that the $KNiFe(CN)_6$ ion exchanger had high selectivity for cesium over sodium.

• Journal of the Korea Convergence Society
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• v.9 no.5
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• pp.15-20
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• 2018

In modern society, crime is one of the major social problems. Crime has a great impact not only on victims but also on those around them. It is important to predict crimes before they occur and to prevent crime. Various studies have been conducted to predict crime. One of the most important factors in predicting crime is frequency of crime occurrence. The frequency of crime is widely used as basic data for predicting crime. However, the frequency of crime occurrence is announced about 2 years after the statistical processing period. In this paper, we propose a frequency analysis of crime - related key words retrieved from the web as a way to indirectly grasp the frequency of crime occurrence. The relationship between the number of frequency of crime occurrence and frequency of actual crime occurrence was analyzed by correlation coefficient.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.3
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• pp.174-178
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• 2013

A modified driving waveform is proposed to improve the address discharge characteristics using wall charge on the common electrodes in plasma display panel. In the driving scheme of plasma display, after a reset period, the negative charge are accumulated on two front electrodes and positive wall charge are accumulated on the address electrode. As the address discharge during an address period is produced when the scan and address pulses are applied at the same time, negative charge on the scan electrodes and positive charge on the address electrodes are mainly used. On the other hand, as the voltage are only maintained without applying the waveform during an address period on the common electrodes, the wall charge is not used on the common electrodes. In this paper, the address discharge characteristics are investigated with changing pulse applying time and applied voltage amplitude on the common electrodes and consequently the producing time of an address discharge are shortened about 200 ns compared with the conventional driving waveform.

• Journal of Aquaculture
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• v.5 no.2
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• pp.167-175
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• 1992

The differences of nutritive components in muscle and viscera of local and Israeli strains of common carp were examined. The crude lipid content in muscle was higher in the local carp than in the Israeli carp, but that in viscera was lower in the local carp than in the Israeli carp. There was no appreciable differences of crude protein and ash in viscera between local and Israeli carp. The distribution patterns of the total amino acid profiles for both local and Israeli carp were very similar. The principal amino acids were aspartic acid, glutamic acid, leucine and Iysine. They were 42 percent of total amino acids. Taurine and histidine were important part of free amino acids. Eicosapentaenoic acid and docosahexaenoic acid content in the polar lipids were high in both strains.

• Korean Journal of Social Welfare
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• v.63 no.4
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• pp.155-181
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• 2011

The purpose of this study was to explore 1) the illness experiences, 2) health behaviors (causal thoughts), and 3) health beliefs (health behavior changes after cancer diagnosis) among Korean breast cancer survivors using focus groups, which is a form of qualitative research methods. Thus, this study intended to understand how the illness experiences and health beliefs are associated with health behaviors. Three focus groups composed of 16 breast cancer survivors living in Seoul and GyeongGi were conducted with 5 to 6 people in each group. For illness experiences, health beliefs, and health behaviors of breast cancer survivors, some major themes related to physical, behavioral, psychological, and social domains were identified. Understanding health beliefs and health behaviors for Korean breast cancer survivors will be an important step toward developing social work interventions for enhancing health promotion.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1399-1406
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• 2011

The reducer of the mixer is one of the main parts of the processor used for water and wastewater treatment. In this study, an advanced reducer with a drywell structure was developed in order to prevent oil leakage during operation in the field. During the development of the advanced reducer prototype, a mockup, a metal mold, and a cast were made using CAD and a CNC machine. The structural safety of the reducer prototype's lower housing (drywell structure) was checked using the ALGOR commercial FEM analysis code, which yielded a von Mises stress of about 123 N/mm2, which is below the yield stress of 250 N/$mm^2$, and a natural frequency of about 650-700 Hz. In addition, the torque transmission efficiency for the advanced prototype was 95.87%, which is about 8% more than that found in a previous study, 88.45%, and the sound level was below 75 dB. Furthermore, no oil leakage or abnormal sound or vibration occurred. Therefore, an optimally designed advanced reducer prototype has been successfully developed.