• The Journal of Engineering Research
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• v.2 no.1
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• pp.39-47
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• 1997

This paper presents a single board digital signal processing system which can perform two-dimensional (2-D) digital infinite impulse response (IIR) filtering in realtime. We have developed an architecture to provide not only the necessary computational power but also a balance of the system input/output and computational requirements. The architecture achieves large system throughput by using highly parallel processing at both the system and processor levels. It reduces system data communication requirements significantly by taking advantage of a custom-designed processor and by providing each processor with its own input and ouput channel. After system initialization, almost 100 percent of the time is used for data processing. Data transfers occur concurrently with data processing. The functional level simulation reveals that the system throughput can reach as high as one pixel per system cycle. With only 10MHz clock frequency system, it can implement up to fourth order 2-D IIR filters for video-rate data ($512\times512$ pixels per frame at 30 frames per second). If we increase the system frequency, the system can be used for the preprocessing and postprocessing of video signal of HDTV.

• Journal of Korean Medicine for Obesity Research
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• v.18 no.1
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• pp.1-9
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• 2018

Objectives: The objective of this study was to assess the safety of 'Gamitaeeumjowee-tang' by analyzing adverse events in weight loss program in combination with 'Gamitaeeumjowee-tang' and low-calorie diet. Methods: A retrospective review of adverse events in weight loss program in combination with 'Gamitaeeumjowee-tang' and low-calorie diet from the electronic medical chart (n=124) between June 2015 and December 2016 was conducted. Three Korean Medicine Doctors (KMDs) reviewed adverse events for two times, during week 2 to 4 and at week 10, after starting weight loss program. Adverse events were evaluated in terms of causality, severity and system-organ classes. Also, agreement among the three KMDs was made through further discussion in case of disagreement after independent review. Results: The overall rate of adverse events was 37.1% during week 2 to 4 and 16.9% at week 10. For causality of adverse events using the World Health Organization-Uppsala Monitoring Centre causality categories, 52.2% were evaluated 'possible' at week 2-4 and 57.1% were evaluated 'unlikely' at week 10. All symptoms were evaluated as 'mild' by LDS scale. Nausea (15, 12.1%) was the most frequent adverse event at week 2-4 and dizziness (6, 4.8%) was the most common at week 10. Conclusions: Adverse events decreased over time. There were no serious adverse events and none of the subjects were dropped due to adverse events. Continuous study is needed to prove the safety of 'Gamitaeeumjowee-tang' for treating obesity.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.4
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• pp.117-122
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• 2021

Permanent magnet synchronous motors can secure high power density and efficiency, but have problems in that the materials required for manufacturing are expensive and design is somewhat more difficult than induction motors. Therefore, it is necessary to develop an optimal motor that considers both efficiency and maintenance convenience and related control research. In addition, driving by a practical motor leads to a request to increase the highest efficiency in a narrow rated range, an increase in average efficiency in the entire electric driving range, and an increase in average output. Due to this movement, a reluctance motor that does not require a permanent magnet is being considered as an alternative. In this paper, in line with the issues of the times that require the development of future technology that can replace rare earth permanent magnet motors and the technological preemption of rare earth reduction motors and rare earth motors, switched reluctance motors without permanent magnet For motor, SRM), modeling through machine language (C language) and the characteristics of SRM accordingly are to be studied.

• Journal of the Korean Society for Library and Information Science
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• v.57 no.3
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• pp.119-141
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• 2023

The COVID-19 pandemic has significantly changed the landscape of knowledge and information services that public libraries around the world have been providing since modern times. In particular, as social distancing has become routine, the contraction of cultural activities and the shift to online platforms have negatively impacted library visitation and use services, greatly reducing borrowing and reading, use of spaces and facilities, interlibrary loan services, program operations, and outreach services. Therefore, this study investigated and analyzed the current status of services provided by public libraries in Korea and abroad in response to COVID-19, and proposed practical ways to improve and expand services in response to COVID-19 based on the results of a survey of librarians' perceptions. Specifically, these include improving the online reservation system for reading and borrowing services and developing and providing various outreach services, acquiring and expanding electronic resources, expanding online program services (reading, culture, lifelong learning, etc.), strengthening library services for vulnerable populations, providing information portal services related to new infectious diseases, strengthening facilities and space provision services, preparing infectious disease response guidelines, and providing education and training to strengthen librarians' capabilities.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.12
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• pp.1-7
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• 2001

Single-layer polymer green electroluminescent devices were fabricated with novel material synthesis by using moleculely-dispersed TTA and NIDI into the polymer PC(B79) emitter layer doped with C6 fluorescent dye which has low operating voltage and high quantum efficiency. A EL cell structure of glass substrate/indium-tin-oxide/PC:TTA:NIDI:C6/Ca/Al was employed and compared with various low work function cathode electrodes Ca and Mg metals. By adjusting the concentration of the fluorescent dye C6, low turn-on voltage of 2.4V was obtained, maximum quantum efficiency of 0.52% at 0.08mole% has been improved by about a factor of ~50 times in comparison with the undoped cell. The PL and EL colors can't be turned by changing the concentration of the C6 dopant. PL emission peaking was obtained at 495nm and EL emission peaking at 520nm with FWHM ~70nm

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.6
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• pp.597-602
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• 2008

This paper examines the damage effect and delay time of CMOS integrated circuits device with coupling caused by high power microwaves. The waveguide and magnetron was employed to study the influence of high power micro-waves on CMOS inverters. The CMOS inverters were composed of a LED circuit for visual discernment. Also CMOS inverters broken by high power microwave is observed with supply current and delay time. When the power supply current was increased 2.14 times for normal current at 9.9 kV/m, the CMOS inverter was broken by latch-up. Three different types of damage were observed by microscopic analysis: component, onchipwire, and bondwire destruction. Based on the results, CMOS inverters can be applied to database to elucidate the effects of microwaves on electronic equipment.

• Ocean and Polar Research
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• v.33 no.1
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• pp.1-11
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• 2011

This study describes measurements of fast ice recorded on May 23, 2009, in Kongsfjorden (translated as 'Kongs Fjord'), an inlet on the west coast of Spitsbergen in the Svalbard Archipelago. Seasonal fast ice is an important feature for Svalbard fjords, both in relation to their physical environment and also the local ecosystem, since it grows seaward from the coast and remains in place throughout the winter. Ice thickness, snow, ice properties, and wind speed were measured, while SAR (Synthetic Aperture Radar) data was observed simultaneously observed two times from ALOS-PALSAR (L-band). Measured ice thickness was about 25-35 cm while the thickness of ice floe broken from fast ice was measured as 10-15 cm. Average salinity was 1.9-2.0 ppt during the melting period. Polarimetric data was used to extract H/A/alpha-angle parameters of fast ice, ice floe, snow and glacier, which was classified into 18 classes based on these parameters. It was established that the area of fast ice represents surface scattering which indicates low and medium entropy surface scatters such as Bragg and random surfaces, while fast ice covered with snow belongs to a zone of low entropy surface scattering similar to snow-covered land surfaces. The results of this study will contribute to various interpretations of interrelationships between H/A/alpha parameters and the wave scattering Phenomenon of sea ice.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.12 no.6
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• pp.582-590
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• 2019

As Korea's low fertility and aging progress, Korea is facing a social change such as an increase of one generation by entering an aging society that has raised 14% of the population. An effective way to prevent a gas fire accident caused by an increase in one generation in an aging society is to install a control valve to forcibly shut off the gas after a set time. In this study, we developed a valve that can be opened and closed by rotating the valve left and right by transmitting power to the worm gear and the helical gear by using a motor by pressing the switch. It is easy to assemble and inspect by developing a dedicated valve that is easy to attach and detach. It was developed to enhance competitiveness by reducing cost by reducing the number of parts and product size. In addition, through endurance test, it was developed to be used for more than 9 years by repeating ON / OFF once every 12 seconds so that it can operate stably for 10,000 times for 34 hours. The instrument and PCB were designed using solid works and Altium Designer tools. Firmware development was developed in IAR Embedded Workbench environment.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.208-208
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• 2013

Graphene has emerged as a fascinating material for next-generation nanoelectronics due to its outstanding electronic properties. In particular, graphene-based field effect transistors (GFETs) have been a promising research subject due to their superior response times, which are due to extremely high electron mobility at room temperature. The biggest challenges in GFET applications are control of carrier concentration and opening the bandgap of graphene. To overcome these problems, three approaches to doping graphene have been developed. Here we demonstrate the decoration of Ni nanoparticles (NPs) on graphene films by simple annealing for p-type doping of graphene. Ni NPs/graphene films were fabricated by coating a $NiCl2{\cdot}6H2O$ solution onto graphene followedby annealing. Scanning electron microscopy and atomic force microscopy revealed that high-density, uniformly sized Ni NPs were formed on the graphene films and the density of the Ni NPs increased gradually with increasing $NiCl2{\cdot}6H2O$ concentration. The formation of Ni NPs on graphene films was explained by heat-driven dechlorination and subsequent particlization, as investigated by X-ray photoelectron spectroscopy. The doping effect of Ni NPs onto graphene films was verified by Raman spectroscopy and electrical transport measurements.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.8 no.6
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• pp.483-490
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• 2015

There are many software reliability models that are based on the times of occurrences of errors in the debugging of software. It is shown that it is possible to do likelihood inference for software reliability models based on finite failure model and non-homogeneous Poisson Processes (NHPP). For someone making a decision about when to market software, the conditional failure rate is an important variables. The infinite failure model are used in a wide variety of practical situations. Their use in characterization problems, detection of outlier, linear estimation, study of system reliability, life-testing, survival analysis, data compression and many other fields can be seen from the many study. Statistical process control (SPC) can monitor the forecasting of software failure and thereby contribute significantly to the improvement of software reliability. Control charts are widely used for software process control in the software industry. In this paper, proposed a control mechanism based on NHPP using mean value function of Musa-Okumo and Power law type property.