• Journal of Power Electronics
• /
• 제15권4호
• /
• pp.1035-1046
• /
• 2015

This study presents a practical implementation of a multi-mode two-phase interleaved boost converter for fuel cell electric vehicle application. The main operating modes, which include two continuous conducting modes and four discontinuous conducting modes, are discussed. The boundaries and transitions among these modes are analyzed with consideration of the inductor parasitic resistance. The safe operational area is analyzed through a comparison of the different operating modes. The output voltage and power characteristics with open-loop or closed-loop operation are also discussed. Key performance parameters, including the DC voltage gain, input ripple current, output ripple voltage, and switch stresses, are presented and supported by simulation and experimental results.

• 통합자연과학논문집
• /
• 제14권2호
• /
• pp.65-72
• /
• 2021

This paper discusses on the implementation of blockchain system, specifically the private system for Energy trading purpose. Blockchain is records bundled together in blocks and added to the chain after ledger is generated. All the blocks in the entire networks should be same contents and also only the permitted nodes can join the chain in the private blockchain system, thus not that same block and permitted nodes cannot be accepted in terms of proof-of-work phase. We implement the all stages which are necessary to process blockchain system. After coding the whole process, we test and conclude that the system is correctly working in terms of the functions implemented.

• International Journal of Internet, Broadcasting and Communication
• /
• 제11권2호
• /
• pp.27-30
• /
• 2019

Factory monitoring systems are gaining importance in wide areas of industry. Especially, there have been many efforts in implementation of vibration measurement and analysis for monitoring the status of rotating machines. In this paper, a digital signal processor (DSP) based monitoring system dedicated to the vibration monitoring and analysis on rotating machines is discussed. Vibration signals are acquired and processed for the continuous monitoring of the machine status. Time domain signals and fast Fourier transform (FFT) are used for vibration analysis. All of the signal processing procedures are done in the DSP to reduce the production and maintenance cost. The developed system could also provide remote and mobile monitoring capabilities to operator via internet connection. This paper describes the overview of the functional blocks of the implemented system. Test results based on signals from small-size single phase motors are discussed for monitoring and defect diagnosis of the machine status.

• Journal of information and communication convergence engineering
• /
• 제20권1호
• /
• pp.16-21
• /
• 2022

In this research, we create a network infrastructure based on a service-oriented infrastructure (SOI) for the virtualization technology and integrate it with a cloud technology that applies the cloud integration management platform (CIMP) concept. In CIMP, the server and storage will be separated. The server will be adopted for virtualization while the storage will be used by students and teachers to store data. As long they save their data in the storage module, every time, everywhere, and on every device, they can access their data. This research will implement the design of the network infrastructure and be applied to the remote practical learning system in the laboratory. Students and teachers will ultimately adopt this network infrastructure for remote practice using their respective devices without physically meeting in the laboratory. In the future, if the implementation phase is successful, then in addition to laboratory environments, it can be implemented in all learning activities at our campus.

• 융합신호처리학회 학술대회논문집
• /
• 한국신호처리시스템학회 2000년도 하계종합학술대회논문집
• /
• pp.265-268
• /
• 2000

In this paper, we propose an algorithm, an optimized architecture, and an implementation for an improved performance of image downscaler. The proposed downscaler uses two-dimensional digital filters for horizontal and vertical scalings, respectively. It also improves scaling precisions and decreases the loss of data, compared with the 1/32 scaler 〔1〕. In order to achieve the optimization, the digital filters are implemented by the multiplexer -adder type scheme 〔2〕. The scaler is designed by using the Verilog-HDL. It is synthesized into gates by using the Samsung 0.35 um STD90 TLM library.

• 한국정보처리학회논문지
• /
• 제3권4호
• /
• pp.877-882
• /
• 1996

Bonhoeffer-Van der Pol(BVP)모델을 실제 소자값을 이용하여 하드웨어를 구현하고 A1 coswt를 인가하여 주기 운동과 카오스 운동을 조사하였다. BVP모델의 하드웨어를 구성하기 위해 컴퓨터 시뮬레이션〔11〕에 의해 구현된 결과를 이용하여 실제 소자값 으로 Rescaling 하였으며 각 계수의 값을 a=0.7, b=0.8, c=0.1로 정하고 주기적 자극 전류의 진폭을 0에서 1.3까지 변화시켜 주기운동에서 카오스 운동으로 천이됨을 위 상공간, 시계열 데이터로 확인하였다.

• Journal of Electrical Engineering and Technology
• /
• 제10권4호
• /
• pp.1655-1666
• /
• 2015

This paper proposes a new approach of Field Programmable Gate Array (FPGA) controlled digital implementation of shunt active power filter (SAPF) under steady state and dynamic operations. Typical implementations of SAPF uses microprocessor and digital signal processor (DSP) but it limited for complex algorithm structure, absence of feedback loop delays and their cost can be exceed the benefit they bring. In this paper, the hardware resources of an FPGA are configured and implemented in order to overcome conventional microcontroller or digital signal processor implementations. This proposed FPGA digital implementation scheme has very less execution time and boosts the overall performance of the system. The FPGA controller integrates the entire control algorithm of an SAPF, including synchronous reference frame transformation, phase locked loop, low pass filter and inverter current controller etc. All these required algorithms are implemented with a single all-on chip FPGA module which provides freedom to reconfigure for any other applications. The entire algorithm is coded, processed and simulated using Xilinx 12.1 ISE suite to estimate the advantages of the proposed system. The coded algorithm is also defused on a single all-on-chip Xilinx Spartan 3A DSP-XC3SD1800 laboratory prototype and experimental results thus obtained match with simulated counterparts under the dynamic state and steady state operating conditions.

• 대한전자공학회논문지SP
• /
• 제45권5호
• /
• pp.118-125
• /
• 2008

이 논문에서 OFDM(Orthogonal Frequency Division Multiplexing) 시스템의 주파수 옵셋 동기화 블록의 효율적인 구조를 제안한다. 기존의 CORDIC(Coordinate Rotation Digital Computer)을 이용한 주파수 옵셋 동기화 블록들은 위상 추정을 위하여 CORDIC Vector 모드를 사용하고, 보상을 위하여 CORDIC Rotation 모드를 사용하고 있다. 이와 비교하여 제안구조는 Vector 모드만을 사용하고 Rotation 모드는 Divider로 대치하는 알고리즘이다. 제안된 방식을 사용함으로써 Rotation 모드를 사용해야 했던 기존의 방식보다 하드웨어 구현복잡도가 감소함을 구현을 통하여 검증하였다. 검증 Tool로 Design Compiler를 사용하였고 각 비교 구조 마다 동일한 Constraint를 적용하여 검증을 진행하였다. 제안구조에 대한 Front-End 칩 구현을 통하여 기존 구조에 비하여 22.1%의 gate count 감소를 보임으로써 저전력 통신용 칩에서 사용할 수 있음을 보였다.

• Journal of Information Technology Applications and Management
• /
• 제24권3호
• /
• pp.23-49
• /
• 2017

This paper is part of the dissertation for an MSc in Project Management and Innovation of Strathclyde Business School The research aims at understanding how IT-SMEs (Small and Medium-sized Enterprises in Information Technology Business) implement and use Flexible Work Arrangements and Flexible Working Hours (FWH/FWA) in their organisations. In-depth interview data was collected from managers and business owners of 31 companies whose needs for Work-Life Balance varied. Results show that many factors positively influence IT-SMEs to use FWH/FWA. For example, customers and partners working at different work-hours, traffic congestions between home and office, and the general stereotype of IT personnel. However, the results also found several concerning factors that may hamper the success of FWH/FWA implementation. They include the inadequacy of management skills in tracking, monitoring, and assessing employee's real performance, contextual factors for Thai IT-SMEs, i.e. conflict resolution culture, IT people's protocol of communication exchanges, and shortcoming of technology infrastructure. The findings also show that many companies that had used FWA eventually stopped. Thus, a four-phase cyclical framework called PLIC (Purpose-Limitation-Implementation-Consequence) has been developed as an approach to FWH/FWA implementation.

• 국제학술발표논문집
• /
• The 9th International Conference on Construction Engineering and Project Management
• /
• pp.1154-1161
• /
• 2022

Building Information Modelling (BIM) has evolved into a comprehensive, collaborative method in construction project delivery. Most industrialized and developed countries have made BIM mandatory in the government and public projects, whereas developing countries are embracing and catching up BIM technologies to improve their professional's abilities and reduce claims in the construction projects. However, BIM awareness and professional's competence have become critical in implementing BIM in infrastructure projects in Nepal, particularly hydropower projects. The objectives of this study are to find the BIM awareness among hydropower professionals in Nepal and assess their response. The study used a questionnaire survey to assess the awareness. The results showed that only few professionals (12 percentage in this study) are aware of BIM and its application in Hydropower infrastructures. Majority of the respondents (more than 50%) were interested in BIM trainings and believed BIM implementation in future projects. The study indicated that lack of BIM training and lack of BIM awareness were the top factors affecting BIM implementation in hydropower projects in Nepal. The findings showed that about 66 percent of the respondents who used BIM in their projects mainly used during construction phase. More than 80 percent believed that BIM should be mandated for the hydropower projects in Nepal. The findings presented in this study could promote awareness among different professionals, organization, and construction team and encourage BIM implementation in Hydropower projects. The findings could raise awareness of BIM in Nepal's infrastructure sectors and its invaluable benefits in construction.