• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.7
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• pp.46-56
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• 2002

In this paper, we describe a hardware-software co-verification methodology and environment in developing a mobile station modem chip for cdma2000 1x which is one of the 3rd generation mobile communication standards. By constructing an efficient co-verification environment for a register-transfer-level hardware model and a physical-layer software model combining a channel link simulator and a versatile test-bench, we can drastically reduce both time and cost for developing a complex three-million-gate class system integrated circuit.

• The Korean Journal of Applied Statistics
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• v.26 no.1
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• pp.49-58
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• 2013

Data envelopment analysis is a relatively new data oriented approach to evaluate the performance of a set of peer entities called decision making units which convert multiple inputs into multiple outputs. It has been extensively applied in performance evaluation and benchmarking entities such as hospitals, universities, cities, courts, and business firms. This study provides the evaluating results of the operational efficiencies of local universities using a DEA approach. In addition, we explore the difference of the efficiency between regional flagship national universities and non-flagships.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.5
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• pp.381-387
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• 2014

This paper introduces a system to machine micro-sized patterns effectively on surface based on micro-milling process using tools with simultaneous rotation and oscillation, oscillation micro milling. To review the effectiveness of proposed concept, we integrated a micro-spindle supported by active magnetic bearings with a precision 3-axis air bearing stage using double-wedge mechanism, and tested this oscillation milling. Two types of oscillation milling were tested, which are linear oscillation milling with a flat end mill and elliptical oscillation milling with a ball end mill with 0.3 mm of diameter. The spindle was rotating 110 krpm and workpiece was moving constant speed of 2~8 mm/sec during the oscillation milling. As the results, multiple oval shape dimples were generated in regular spacing, and the variation of elliptical motion made different shapes of patterns. The results showed that proposed oscillation milling can be successfully used for machining repeated micro-patterns.

• Elastomers and Composites
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• v.44 no.3
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• pp.222-231
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• 2009

Shirasu-porous-glass (SPG) membrane emulsification is highly attractive in the field of toner industries, foods and drug delivery systems because of its easy control of particle size in micro-scale, narrow size distribution and multiple emulsion. The particle size and morphology of emulsion droplets can be controlled by changing the type of initiators, additives, monomers, crosslinkers and inhibitors in SPG membrane emulsification. In this paper, principles of SPG membrane emulsification, influence of process parameters and industrial applications have been addressed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.4
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• pp.480-484
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• 2008

The incidence of aspergillosis infections in the maxillary sinus has increased recently, because of overuse of antibiotics, steroids, anticancer agents, immunosuppressant, antimetabollites, and uncontrolled diabetes mellitus. The clinical features of maxillary sinus aspergillosis include pain, swelling and foul odor nasal excretion. This needs to be differentiated from bacterial maxillary sinusitis, and surgical treatment with antifungal agents are suggested. Recently, we treated two patients with maxillary sinus aspergillosis surgically (Caldwell Luc operation) and with antifungal agents(itraconazole). The results were satisfactory so we report these cases with literature review.

• Korean Security Journal
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• no.41
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• pp.153-183
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• 2014

Nowadays, proactive intelligence activities are required because of enhanced nation wide threats of terrorism and complexity of multidimensional factors of national security. South Korea not only need to draw up plans of information sharing among agencies for more effective national intelligence activities, but also have to evaluate the structure of Domestic Intelligence Agency and its right direction of activities. In this vein, this paper conducts comparative studies of structures and range of activities of intelligence Agencies by reviewing U.K, U.S.A, and France cases and suggests a potential model of 'domestic information specified agency' that we can adopt and methods to share information among agencies. The focus of this paper is on the reviewing of necessity of establishing new 'domestic information specified agency' which will mainly conduct anti-terrorism and counterintelligence activities, and its appropriate form. After reviewing the cases of U.K, U.S.A. and France, we conclude that overcoming the people's distrust about an invasion of freedom and rights caused by centralized and integrated independent intelligence agency is a prerequisite. Disputable issues of FBI, DHS, and South Korea's intelligence agency cases suggest that plans for restoring trust have to be considered if a new 'domestic information specified agency' is established in NIS. If it is established under government ministries such as MSPA focusing on implementing anti-terrorism and counterintelligence activities, organizations such as NCTC, NIC, that can carry out information sharing and cooperating with agencies concerned have to be established. Additionally, measures to solve structural problems caused by carrying out law enforcement functions by domestic information specified agency should be considered.

• Korean Security Journal
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• no.49
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• pp.157-183
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• 2016

Countries across the globe, including those in Europe, are waging a "war against terrorism" as international terrorist groups such as ISIS and lone-wolf terrorists have unleashed various large-scale attacks on rail infrastructure. Anti-South Korean sentiment exists in Muslim-majority countries because the nation has cooperated with the US for its military interventions in the Middle East, and ISIS has threatened to target South Korea four times since September 9, 2015. In addition, North Korea has been left isolated in the international community with its missile and nuclear tests, while further escalating inter-Korean tension and threatening to strike major facilities and attack important figures in the South. These situations imply that South Korea is no longer immune to terrorist attacks. If the nation fails to prevent or deter such terrorist attacks against rail networks, massive casualties, property damage and social confusion would be unavoidable, deteriorating national and international trust in its counter-terrorism policies. This may lead to a national crisis involving decreases in the number of tourists, dampened interest of foreign investors, and capital flight. This study aims to propose policy measures to enhance railroad security checks, based on the work of railroad police officers, for the sake of protecting citizens and public safety. The suggestions include an incremental expansion of railroad security checks; growth of the railroad police force and adjustment of their policing distribution with other police officers; enhancement of security systems across important rail networks; improvement of the Railroad Safety Act; Southeast Asia, including the corresponding strengthening of the national crackdown illegal immigrants, and plans for pre-emptive and regular cooperation among organizations related to the promotion of security checks and the prevention of terrorist attacks.

• Journal of Advanced Navigation Technology
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• v.11 no.4
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• pp.371-377
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• 2007

Ionospheric time delay is one of the main error source for single-frequency DGPS applications, including time transfer and Wide Area Differential GPS (WADGPS). Grid-based algorithm was already developed for WADGPS but that algorithm is not applicable to geomagnetic storm condition in accuracy and management. In geomagnetic storm condition, the spatial distribution of vertical ionospheric delay is noisy and therefore the accuracy of modeling become low in grid-based algorithm. For better accuracy, function based algorithm can be used but the continuity of correction message is not guranteed. In this paper, we propose the ionospheric model using wavelet based algorithm. This algorithm shows better accuracy with the same number of correction message than the existing spherical harmonics algorithm and guarantees the continuity of correction messages when the number of message is expanded for geomagnetic storm condition.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.5
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• pp.118-125
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• 2004

The use of electric arc furnace has been increasing as the steel consumption is increasing and the operation technique of electric arc furnace are developing. But as the use of electric arc furnace is increased, the furnace have produced the adverse effects of power quality: voltage and current harmonics, voltage and current imbalances, low power factor, and voltage flicker. One of the power quality problems, the harmonic have the characteristics of the time-varying and non-linear. This paper analyzed the harmonics for the various operation conditions of electric arc furnace. The power system model with electric arc furnace have been made, and the harmonic's effects on the power system has been analyzed according to the various operating conditions, first melting, second melting, so on. Also, the filter reducing the harmonic components have been designed and its effects on the power system have been examined.

• Korean Journal of Medicinal Crop Science
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• v.20 no.3
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• pp.165-170
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• 2012

This study was conducted to evaluate the effect of light spectrum using red (660 nm), blue (460 nm), red and blue mixed (Red : Blue = 6 : 4) LED (light-emitting diode), and fluorescent lamp on antioxidant activities and functional components of dandelion (Taraxacum officinale). Total polyphenol contents in dandelion irradiated with the red and blue mixed or the red LED were 121.77 mg/100 g or 115.36 mg/100 g, respectively, which were greater than those in dandelion treated with blue LED and fluorescent lamp. Asparagine showed the highest content among amino acids in leaves and roots regardless of treatments. Total amino acid was the highest when illuminated with the red LED. DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging activity and SOD (super oxide dismutase) activity of ethanol extracts were increased under all of the LED treatments compared with fluorescent lamp, and the antioxidant activities were increased by the red and the mixed LED illumination. The results indicate that application of the red and the mixed LED illumination promote antioxidant activity and increase functional components during cultivation of dandelion.