• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.11
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• pp.1311-1316
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• 2014

To be used in a transmitter of a satellite transponder of this paper, X band 25W power amplifier module, a part constituting of high-power amplifier is transmitted to the equipment for transmitting to geostationary communications satellites(36,000Km distance). PAM consisted a total of four power amplifier module has a high output characteristic of the high-output amplifier is used in the ground station. Used in conjunction with the structured type power amplifier module is composed of Serial Combining Structure. This PAM(Power Amplifier Module) configured by combining the circuit with the power amplifier, 10 MMIC chips and the Al2O3 thin film substrate using a Hybrid Technique of power amplifier module, was implemented at X band PAM(Power Amplifier Module) of 25W grade.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.6 s.97
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• pp.580-585
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• 2005

Two high-efficiency and high power power-combing modules were developed using slotline-to-microstrip transition at V-band. Power-combining modules incorporating two MMIC power amplifiers demonstrated combining efficiencies higher than $80\%$(maximum $86\%$) with saturated output power of 22.96 dBm and 22.81 dBm, respectively. The measurement of back-to-back connected combiners demonstrated insertion loss less than 1.2 dB with return loss better than 15 dB around 60 GHz, respectively.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.1
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• pp.231-238
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• 2019

In this paper, we have studied how to improve the amplifiers efficiency by minimizing the combining loss when several unit power amplifiers are combined to obtain high output power. Specifically, we have developed Ka-band Spatial Combining Amplifier. The fabricated Spatial Combining Amplifier is a Ka-band 20W class SSPA, which uses a 5W class unit amplifier module 8EA designed using a GaN bare die. We also combined The unit amplifier module using 8-way spatial divider and combiner with a hybrid radial structure. The output combining loss of the fabricated spatial coupler is about 0.334dB, which is about 92.6% efficiency. In this paper, we developed a Spatial Combining Amplifier with a maximum saturation output of 10W and a power addition efficiency of over 15%. As a result, we achieved the maximum saturation output of 30W and the power addition efficiency of 19%.

• Journal of Fashion Business
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• v.25 no.6
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• pp.25-45
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• 2021

Due to the fashion industry taking responsibility for their garment manufacturing, a significant number of UK universities are focusing on combining sustainability in their curriculum to support future employees' skills and knowledge in sustainable fashion. A proper understanding of educational and instructional theories is needed to develop effective teaching and learning materials and environments. Therefore, this study aimed to evaluate the Fashion Design module created with consideration of sustainability using ADDIE instructional model. For evaluation, the teaching materials, including the module brief and the PowerPoint slides for each session, were used. Ten students were interviewed and observed along with two tutors, also interviewed to analyze the strengths and weaknesses of the module from a variety of viewpoints. With sustainable fashion being embedded into specialized higher education courses, tutors decided to incorporate sustainability into the module as an introduction to this topical subject in order to build a stronger foundation of knowledge and challenge traditional ways of working. Results showed that combining sustainability into the design and technical sessions had a positive influence on students who built upon their existing knowledge. Tutors researched the need for change within the industry in line with the Sustainable Development Goals and aligned the content to inform the students of the current crisis. This study could provide a guideline to create instructional material for sustainable fashion design courses.

• Journal of the Semiconductor & Display Technology
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• v.21 no.4
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• pp.110-115
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• 2022

Accurate current-voltage modeling of solar cell systems plays an important role in power prediction. Solar cells have nonlinear characteristics that are sensitive to environmental conditions such as temperature and irradiance. In this paper, the output characteristics of photovoltaic module are accurately predicted by combining the artificial neural network and physical model. In order to estimate the performance of PV module under varying environments, the artificial neural network model is trained with randomly generated temperature and irradiance data. With the use of proposed model, the current-voltage and power-voltage characteristics under real environments can be predicted with high accuracy.

• Current Photovoltaic Research
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• v.8 no.1
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• pp.12-16
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• 2020

This study investigates the degradation characteristics of different material types of ethyl vinyl acetate (EVA) and polyolefin (POE) with combining transparent backsheet. To this end, we fabricated samples with structure of glass/encapsulant/transparent backsheet for each type of encapsulants, and shingled Si modules with the same structure. The samples were then subjected to accelerated test by storing under damp heat condition of 85℃ and 85% RH. As a result, encaplsulant discoloration was observed, which the transmittance of the samples with EVA decreased in a rapid rate than the samples with POE. The discoloration also affected a power degradation of the shingled modules with a reduction of current density, resulting that the module with EVA showed more drop on the efficiency than the modules with POE. Furthermore, corrosion of the soldered ribbon caused by acetic acid produced from the degraded EVA also contributed in fill factor reduction.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.367-371
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• 2004

This paper describes development of automatic flight control system for an unmanned target drone which is operated by Korean army as for anti-air gun shooting training. Current target drone is operated by pilot control of on-board servo motor via remote control system. Automatic flight control system for the target drone greatly reduces work load of ground pilot and can increase application area of the drone. Most UAVs being operated now days use high-priced sensors as AHRS and IMU to measure the attitude, but those are costly. This paper introduces the development of low-cost automatic flight control system with low-cost sensors. The integrated automatic flight control system has been developed by integrating combining power module, switching module, monitoring module and RC receiver as an one module. The performance of automatic flight control system is verified by flight test.

• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3595-3603
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• 2022

Nuclear safety-class DCS is used for nuclear reactor protection function, which is one of the key facilities to ensure nuclear power plant safety, the maintenance for DCS to keep system in a high reliability is significant. In this paper, Nuclear safety-class DCS system developed by the Nuclear Power Institute of China is investigated, the model of reliability estimation considering nuclear power plant emergency trip control process is carried out using Markov transfer process. According to the System-Subgroup-Module hierarchical iteration calculation, the evolution curve of failure probability is established, and the preventive maintenance optimization strategy is constructed combining reliability numerical calculation and periodic overhaul interval of nuclear power plant, which could provide a quantitative basis for the maintenance decision of DCS system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.1
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• pp.162-167
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• 2012

In power quality monitoring, it is very important to detect disturbances (sag, swell, transient, and interruption) accurately. In this paper, a detection method for power quality disturbances by combining the filter bank system and adaptive filter is proposed. To decompose power signal, binary tree structured filter bank system is designed. In the filter bank system, the fundamental filter bank(QMF bank) is used as a module in each decomposing level. An adaptive filter is used to improve the detection accuracy of disturbances for each subband signal. In the adaptive filter, the measure of estimated error change is used to detect singular points of power quality disturbances. Computer simulations were performed on synthetic signals which have disturbances to assess the performance of the proposed method.

• Journal of the Korean Society of Mechanical Technology
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• v.20 no.6
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• pp.803-808
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• 2018

Combining digital automation solutions throughout recent manufacturing process is essential. Advanced robot and mechanical techniques are required for design, manufacture, and distribution process. Manual design of repetitive similar mechanical components during the development phase of these advanced machines and robots can occur wasting time and money. Developed gear design module, which is the power transfer system mechanical component, was programmed in the Visual Basic language in CATIA V5 environment. Automation Process is Based on Parametric Modeling Method. and it was found to be effective in reducing design time compared to designers manual modeling.