• Nuclear Engineering and Technology
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• v.49 no.8
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• pp.1589-1599
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• 2017

Field programmable gate arrays (FPGAs) are getting more attention in safety-related and safety-critical application development of nuclear power plant instrumentation and control systems. The high logic density and advancements in architectural features make static random access memory (SRAM)-based FPGAs suitable for complex design implementations. Devices deployed in the nuclear environment face radiation particle strike that causes transient and permanent failures. The major reasons for failures are total ionization dose effects, displacement damage dose effects, and single event effects. Different from the case of space applications, soft errors are the major concern in terrestrial applications. In this article, a review of radiation effects on FPGAs is presented, especially soft errors in SRAM-based FPGAs. Single event upset (SEU) shows a high probability of error in the dependable application development in FPGAs. This survey covers the main sources of radiation and its effects on FPGAs, with emphasis on SEUs as well as on the measurement of radiation upset sensitivity and irradiation experimental results at various facilities. This article also presents a comparison between the major SEU mitigation techniques in the configuration memory and user logics of SRAM-based FPGAs.

• Journal of electromagnetic engineering and science
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• v.14 no.2
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• pp.68-73
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• 2014

A linear stacked field-effect transistor (FET) power amplifier (PA) is implemented using a $0.18-{\mu}m$ silicon-on-insulator CMOS process for W-CDMA handset applications. Phase distortion by the nonlinear gate-source capacitance ($C_{gs}$) of the common-source transistor, which is one of the major nonlinear sources for intermodulation distortion, is compensated by employing a PMOS linearizer with improved AM-PM. The linearizer is used at the gate of the driver-stage instead of main-stage transistor, thereby avoiding excessive capacitance loading while compensating the AM-PM distortions of both stages. The fabricated 836.5 MHz linear PA module shows an adjacent channel leakage ratio better than -40 dBc up to the rated linear output power of 27.1 dBm, and power-added efficiency of 45.6% at 27.1 dBm without digital pre-distortion.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.8
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• pp.1847-1853
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• 2014

The PAPR of the input signal is increased due to OFDMA signal in a mobile communication system. High efficiency of a power amplifier, which accounts for power consumption, is a very important key technology. Digital Pre-Distortion techniques were used to improve the linearity of the power amplifier. The Asymmetric Doherty scheme was used to improve the efficiency of the power amplifier. In this paper, we propose a new structure of Asymmetric Doherty. Drive power amplifier part is separated as main path and peak path, and phase shifter is employed to improve power combine characteristics of the Doherty Amplifier. Also, envelope tracking technology for drive gate bais in drive peak amplifier is used to improve efficiency.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.48-51
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• 2004

In this paper the importance of re-nitridation on a plasma-enhanced chemical-vapor deposited(PECVD) $SiO_2$ stacked on a thermally grown thin-nitrided $SiO_2$ on n-type 4H SiC have been investigated. Without the final re-nitridation process, the leakage current of metaloxidesemiconductor(MOS) was extremely large. It is believed that water and carbon, contamination from the low-thermal budget PECVD process, are the main factors that destroyed the high quality thin-buffer nitrided oxide. After re-nitridation annealing, the quality of the stacked gate oxide was improved. The reasons of this improvement are presented.

• Journal of architectural history
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• v.28 no.4
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• pp.17-26
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• 2019

After opening Suwon railway station in 1905, a new road was constructed between Suwon station and Paldalmun(the South gate). It was the starting point to change urban structures of Suwon and shape the new city scape. In 1914, administrative districts of Suwon were reorganized. Suwon-myeon (township, a subdivision of Suwon-gun) was promoted to Suwon-eup(town) in 1931. Suwon-eup expanded its territory and changed the address system from 'li(里)' system to Japanese address system, 'Jeong(町)' in 1936. From 1920s, road system was changed and transformed Suwon's urban structures. A straight road was built from Jongro intersection to Janganmun(the north gate) in 1928. Another straight road was constructed between Suwon station to Padamun in the early 1930s. Public office buildings used the Hwa Seong HaengGung(華城行宮) and some of building moved to new location with new buildings. Main buildings of most schools in Suwon were reconstructed since 1930s. Commercial buildings and stores were sprung up and had their own characteristics by region. Around Suwon station, there are more hotels and restaurants than other areas. Rearranging administrative areas, developing road system and new buildings transformed Suwon's spatial structures. Constructing new roads formed a straight road passing through Suwon. After reorganizing administrative areas, this road turned to be the central axis of Suwon. Buildings in new style on the axis made the modern cityscape in Suwon.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.2
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• pp.3-10
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• 2019

The purpose of the study is to survey the effective methodology of composition and connection for the third pedestrian routes in mixed-use building by case studies. The study is performed as follows: First of all, pedestrian routes are classified into malling route, evacuation route, and the Third route. Secondly, case studies are conducted based on the classification. Thirdly, it is investigated about the composition and connection of the malling and the Third pedestrian route. The investigation is focused on gate, path, central area, vertical circulation(EV and escalator) and the four circulation elements. Finally, the effective methodology is extracted for setting the Third route in mixed-use buildings. The conclusion of the study is as follows: The enhancement of consistency and connection between the main route and the Third route is important for providing convenient paths especially to users who needs shortcut, EV/ES users. Additionally, the connections between EV and gate, between shortcut and EV/ES should be increased to enable users choosing their path as needed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.4
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• pp.43-49
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• 2021

A small infrared image homing system is a tracking system that has an infrared image sensor that identifies a target through the day and night infrared image processing of the target on the ground and searches for and detects the target with respect to the main target. This paper describes the development of a board equipped with a high-speed CPU and FPGA (Field Programmable Gate Array) to identify target through real-time image processing by acquiring target information through infrared image. We propose a CPU-FPGA combining architecture for CPU and FPGA selection and video signal processing, and also describe a controller design using FPGA to control infrared sensor.

• Nuclear Engineering and Technology
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• v.55 no.1
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• pp.248-253
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• 2023

Directly, it is not possible to measure the absorbed dose of radiopharmaceuticals in the organs of the human body. Therefore, simulation methods are utilized to estimate the dose in distinct organs. In this study, individual organs were separately considered as the source organ or target organ to calculate the mean absorption dose, which SAF and S factors were then calculated according to the target uptake via MIRD method. Here, ^99mTc activity distribution within the target was analyzed using the definition and simulation of ideal organs by summing the fraction of cumulative activities of the heart as source organ. Thus, GATE code was utilized to simulate the Zubal humanoid phantom. To validate the outcomes in comparison to the similar results reported, the accumulation of activity in the main organs of the body was calculated at the moment of injection and cardiac rest condition after 60 min of injection. The results showed the highest dose absorbed into pancreas was about 21%, then gallbladder 18%, kidney 16%, spleen 15%, heart 8%, liver 8%, thyroid 7%, lungs 5% and brain 2%, respectively, after 1 h of injection. This distinct simulation model may also be used for different periods after injection and modifying the prescribed dose.

• Journal of architectural history
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• v.24 no.3
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• pp.17-29
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• 2015

This study is about the change of multi-storied buildings in Hanyang, the capital city of Joseon Dynasty. The changes are divided into 3 phases in the viewpoint of architectural types and building types. The first phase is from the early Joseon Dynasty to the time of Japanese invasion to Korea and Sungryemun remains until now. The second phase is from 1592 to the the first half of the 18th century. Many multi-storied Buddhist halls were rebuilt at that time. In the final phase, many multi-storied gate buildings and multi-storied main buildings of palaces were rebuilt. And there are differences between the Buddhist buildings and the main buildings of palaces. By the way the change that architectural style of the Buddhist buildings and the main buildings of pal were switched and mixed occurred. For example, Anguksa Daeungjeon adopted the style of multi-storied gates and Injeongjeon adopted the style of multi-storied Buddhist halls. These phenomenon was result from periodical situation the monk carpenter and his disciple took part in governmental construction like Janganmun.

• The Journal of Korean Medicine
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• v.19 no.2
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• pp.194-210
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• 1998

The main purpose of this work is the study on the etiology and pathology of the anorexia in oriental and western medicine. An appetite is stimulated by the need of supply of nutrition for life and the physical desire of hunger which appeared as the alternative of taste. In this paper, I investigated the anatomical and the physiological function system, the Piwei functional system and meridian distribution, and the differentiation of the disease according to the Zangfu(internal organs) in association with the anorexia. And conclusion could be summarized as follows : 1. The tongue, one of the Piwei functional system(脾胃機能系), is connected with Pi(脾), Xin(心), Gan(肝) and Shen(腎) meridian. Especially Pi and Xin meridian have the close relations with taste. 2. The appetite has the close relations with Piwei. The appetite and digestion is influenced by the function of smoothing and regulating and bloodflow of Ki(肝主疏泄), warming the Shen to activate the function of Pi(腎主溫養), cleansing the inspired air and keeping the Ki flowing downward(肺主肅降). 3. The cause of anorexia is the insufficiency of Ki of Piwei(脾胃氣虛), the attack of Wei by hyperactive Gan Ki(脾氣犯胃), the insufficiency of Wei Yin(胃陰不足), the declination of the fire from the vital gate(命門火衰) and the retention or stagnancy of undigested food (飮食停滯). Especially, the main cause of anorexia is the insufficiency of Ki of the Piwei(脾胃氣虛). 4. Recently the attack of Wei by hyperactive Gan Ki(脾氣犯胃) is raised by the main cause of anorexia. 5. The mental function of anorexia, which is induced by the unbalance of Pi, is directly associated with Xin(心) and Xin meridia(心經). 6. The goal of the treatment of the anorexia is dependent on the recovery of the weakness of the Pi. And for this goal, the disorders of the other organs is also treated. 7. In the point of the anatomy and physiology, the main cause of anorexia is the loss of function of the autonomic nerve system and the vagus nerve.