• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.2
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• pp.213-221
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• 2011

Avionics system tends to be designed to have the integrated architecture, and it is getting difficult and complex to verify the flight-critical function because of sophisticated structure. In Korean Utility Helicopter, mission computer acts as the MUX Bus Controller to handle the data from both communication, identification, mission/display and survivability equipment inside Mission Equipment Package and aircraft subsystems such as fuel system and electrical system while it is interfacing with Automatic Flight Control System and Full-Authority Digital Engine Control via ARINC-429 bus. The Flight Displays which is classified as flight-critical function in aircraft is implemented on Primary Flight Display after mission computer processes data from AFCS in order to generate graphics. This paper defines the flight-critical function implemented in mission computer for KUH, and presents the static and dynamic test procedures which is performed on System Integration Laboratory along with Playback Recorder prior to flight test.

• Journal of Distribution Science
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• v.19 no.3
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• pp.15-23
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• 2021

Purpose: This study aims to identify the role of technological progress in the distribution sector in Saudi Arabia. Research design, data, and methodology: The study applies the Autoregressive Distributed Lag (ARDL) approach to estimate the Cobb Douglas production function of the wholesale and retail trade sector in Saudi Arabia, relied on annual data from the General Authority for Statistics from 2005 to 2019. Results: The results show that there is a long run relationship between the production of the wholesale and retail trade sector in KSA and the factors of production labour, capital and technology progress. The elasticity of the wholesale and retail trade production with respect to capital and labour are 0.26 and 0.78 respectively; the coefficients are positive and statistically significant. The wholesale and retail trade sector is operating under increasing returns to scale. The main result indicates that the elasticity of the wholesale and retail production with respect to the technology progress is 4.62%, which is positive and statistically significant. Conclusions: The study concluded that technological progress has a positive contribution to the growth of the distribution sector in KSA. Therefore, the technological progress can improve the productivity and efficiency of the resources allocated to the dis.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.6
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• pp.3280-3298
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• 2019

Vehicular ad-hoc networks (VANETs) have become increasingly significant in intelligent transportation systems, they play a great role in improving traffic safety and efficiency. In the deployment of intelligent VANETs, intelligent vehicles can efficiently exchange important or urgent traffic information and make driving decisions. Meanwhile, secure data communication and vehicle's identity privacy have been highlighted. To cope with these security issues, in this paper, we construct an efficient anonymous authentication scheme with secure communication in intelligent VANETs. Combing the ElGamal encryption technique with a modified Schnorr signature technique, the proposed scheme provides secure anonymous authentication process for encrypted message in the vehicle-to-infrastructure communication model, and achieves identity privacy, forward security, and reply attack resistance simultaneously. Moreover, except the trusted authority (TA), any outside entity cannot trace the real identity of an intelligent vehicle. The proposed scheme is designed on an identity-based system, which can remove the costs of establishing public key infrastructure (PKI) and certificates management. Compared with existing authentication schemes, the proposed scheme is much more practical in intelligent VANETs.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.874-882
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• 2017

As the interest on the air-pollution is gradually rising up at home and abroad, automotiv e and fuel researchers have been working on the exhaust emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative after-treatment systems, using clean (eco-friendly alternative) fuels and fuel quality improvement. This research has brought forward three main issues : evaporative, performance, air pollution. In addition, researcher studied the environment problems of the bio-ethanol, bio-butanol, bio-ETBE (Ethyl Tertiary Butyl Ether), MTBE (Methyl Tert iary Butyl Ether) fuel contained in the fuel as octane number improver. The researchers have many dat a about the health effects of ingestion of octane number improver. However, the data support the con clusion that octane number improver is a potential human carcinogen at high doses. Based on the bio-fuel and octane number improver types (bio-ethanol, bio-butanol, bio-ETBE, MTBE), this paper dis cussed the influence of gasoline fuel properties on the evaporative emission characteristics. Also, this p aper assessed the acceleration and power performance of gasoline vehicle for the bio-fuel property. As a result of the experiment, it was found that all the test fuels meet the domestic exhaust gas standards, and as a result of measurement of the vapor pressure of the test fuels, the bio - ethanol : 15 kPa and the biobutanol : 1.6 kPa. thus when manufacturing E3 fuel, Increasing the biobutanol content reduces evaporation gas and vapor pressure. In addition, Similar accelerating and powering performance was shown for the type of biofuel and when bio-butanol and bio-ethanol were compared accelerated perf ormance was improved by about 3.9% and vehicle power by 0.8%.

• Nuclear Engineering and Technology
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• v.56 no.7
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• pp.2516-2523
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• 2024

This study aims to validate the dosimetric characteristics of Low Dose Rate (LDR) I-125 source Geant4-based Monte Carlo code. According to the recommendation of the American Association of Physicists in Medicine (AAPM) task group report (TG-43), the dosimetric parameters of a new brachytherapy source should be verified either experimentally or theoretically before clinical procedures. The simulation studies are very important since this procedure delivers a high dose of radiation to the tumor with only a minimal dose affecting the surrounding tissues. GEANT4 Monte Carlo simulation toolkit associated brachytherapy example was modified, adapted and several updated techniques have been developed to facilitate and smooth radiotherapy techniques. The great concordance of the current study results with the consensus data and with the results of other MC based studies is promising. It implies that Geant4-based Monte Carlo simulation has the potential to be used as a reliable and standard simulation code in the field of brachytherapy for verification and treatment planning purposes.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.8
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• pp.325-334
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• 2021

The study investigates the effectiveness of the macroprudential policy on credit growth in Vietnam. The authors use the logic of the transmission mechanism of macroprudential policy on credit growth. Research variables include economic growth, inflation, interest rate, and quarterly bank-level data from 28 commercial banks in Vietnam during 2011-2018. The results reveal that: (i) GDP growth had a positive impact on credit growth of small banks but had no impact on large banks, (ii) Domestic Systemically Important Banks (D-SIBs) and small banks respond differently to macroprudential measures of imposing different credit growth targets for different bank groups, (iii) Restrictions on foreign currency loans are found to be effective in curbing credit growth for the full sample and small banks, (iv) Inflation and economic cycle have significantly impacted credit growth at bank-level in Vietnam and (v) Interestingly, a significant positive relationship between interest rates and credit growth is found for the full sample and D-SIBs in Vietnam. The findings suggest that a stable macroeconomic environment should be good conditions for financial stability, and monetary authority should pay more attention to small banks' behaviors than D-SIBs behavior, toward such "administration" tools since small banks tend to prefer "breaking the rules" to make profits.

• Proceedings of the Korea Contents Association Conference
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• 2006.05a
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• pp.495-498
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• 2006

Domestic information service authority and company provide database services to introduce the newest scientific and technological information, trend, and research data. Among many databases, FSTA((Food Science and Technology Abstracts)) is a bibliographic database providing worldwide coverage of all scientific and technological aspects of the processing and manufacturing of human food products. To service FSTA database through KRISTAL search engine developed by KISTI(Korea Institute of Science and Technology Information) need many process such as data obtainment, building, search, modification, rebuilding, and statistics. In this paper, we present implementation of management tool used to build FSTA database effectively. The management tool provides graphical user interface and controls all process from data obtainment to building of KRISTAL information searching system. By building FSTA database fast and accurately, user can get information that they want to find from the newest FSTA database.

• Nuclear Engineering and Technology
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• v.56 no.9
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• pp.3898-3903
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• 2024

There is a lack of available data on the radioactivity levels of these materials, despite the potential risks they may pose to patients, dental technicians, and dentists. A total of forty samples were collected from different dental markets in Egypt. Using an NaI(Tl) detector, the gamma-ray spectrometer measured the activity levels of uranium-238, radium-226, thorium-232, and potassium-40. The findings revealed that the mean concentration of ²³⁸U (below the minimum detectable activity, MDA), ²²⁶Ra (135 ± 5 and 132 ± 5 Bq/kg), ²³²Th (187 ± 4 and 243 ± 8 Bq/kg), and ⁴⁰K (1560 ± 52 and 2501 ± 89 Bq/kg) in feldspar and zirconia (ZrO₂) dental ceramic samples, respectively, were all within the limits established by the International Organization for Standardization (ISO) and the European Commission (EC). The use of feldspar and zirconia dental ceramics to restore all teeth would result in an estimated maximum beta dose of 1.5 mGy/year to the oral tissue. The results suggest that there is no cause for concern regarding any additional beta dose to the oral cavity from the use of feldspar and zirconia dental ceramics.

• Nuclear Engineering and Technology
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• v.52 no.4
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• pp.819-826
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• 2020

The method of the Laplace transform has been used to obtain an analytical solution of the three-dimensional steady state advection diffusion equation for the airborne radionuclide release from any nuclear installation such as the power reactor in an area source. The present treatment takes into account the removal of the pollutants through the nuclear reaction. We assume that the pollutants are emitted as a constant rate from the area source. This physical consideration is achieved by assuming that the vertical eddy diffusivity coefficient should be a constant. The prevailing wind speed is a constant in 𝑥- direction and a linear function of the vertical height z. The present model calculations are compared with the other models and the available data of the atmospheric dispersion experiments that were carried out in the nuclear power plant of Angra dos Reis (Brazil). The results show that the present treatment performs well as the analytical dispersion model and there is a good agreement between the values computed by our model and the observed data.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.2
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• pp.287-293
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• 2012

It has been only few years that various contents information subject for information processing system has been remarkably increased in online. If we say the year 2000 is the technology based year when deluge of information and data such as real time sharing, the time since after 2000 until 2011 has been a period plentiful of application based functions and solutions. Also, as the applicable range of these information process systems extends, individual information effluence has been social issues twice in 2009 and 2010. Thus now there are continuous efforts made to develop technologies to secure and protect information. However, the range problem has been extended from the illegal access from outside to the legal access from internal user and damages by agents hidden in internal information process system and client system. Therefore, this study discusses the necessity for the studies on efficiency based information security by control of access to internal information and authority setting for administrator and internal users. Based on the result of this study, it provides data that can be used from SOHO class network to large scale for information security method.