• Journal of electromagnetic engineering and science
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• v.17 no.3
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• pp.138-146
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• 2017

A phase-locked dielectric resonator oscillator (PLDRO) is an essential component of millimeter-wave communication, in which phase noise is critical for satisfactory performance. The general structure of a PLDRO typically includes a dual loop of digital phase-locked loop (PLL) and analog PLL. A dual-loop PLDRO structure is generally used. The digital PLL generates an internal voltage controlled crystal oscillator (VCXO) frequency locked to an external reference frequency, and the analog PLL loop generates a DRO frequency locked to an internal VCXO frequency. A dual loop is used to ease the phase-locked frequency by using an internal VCXO. However, some of the output frequencies in each PLL structure worsen the phase noise because of the N divider ratio increase in the digital phase-locked loop integrated circuit. This study examines the design aspects of an interconnected PLL structure. In the proposed structure, the voltage tuning; which uses a varactor diode for the phase tracking of VCXO to match with the external reference) port of the VCXO in the digital PLL is controlled by one output port of the frequency divider in the analog PLL. We compare the proposed scheme with a typical PLDRO in terms of phase noise to show that the proposed structure has no performance degradation.

• Journal of the Korea Furniture Society
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• v.21 no.4
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• pp.326-337
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• 2010

The invention and development of digital computer networks since the post-modern culture and creating new ideas, and in nearly all areas since the industrial revolution has had the greatest impact. A new paradigm for the 21st century, the Internet and ubiquitous, and mobile devices are being created by the new culture is being created. Rapidly being replaced by digital and analog, and 'Digilog' fusion concept has appeared. In addition, the development of computer cyberspace culture, art, design and structure are changing. In the field of furniture design, changing design processes and innovative design philosophy that change is now occurring. These symptoms experienced at the same time, almost every country on Earth is a phenomenon. Since the 20th century, computer network design based on the relationship between digital and cyber culture espoused by philosophers studied society and organic modernism and organic design of digital-based differences are confirmed through the case. Using digital technology, modeling case study of a furniture designer in cyber space and the creation of human capabilities and the fusion of computing power will be studied in modern furniture design.

• Korean Institute of Interior Design Journal
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• v.13 no.4
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• pp.188-195
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• 2004

The evolutions of human mental capability and technology opened a new era called "Digital Space." Moreover, Digital Space as technology is already accelerating the process of "self-expansion." The expansion, on the foundation of its conceptual and morphological variety, acquired the potential to furnish various types of spatiotemporal experience. This phenomenon, as a necessary consequence of focusing on the resulting value of the human-space relation which came next to its ontological value, requests the value of the space design as an attempt of various phenomenal experience in the relation of technology, human, and space to be educationally established. From a typological point of view, no true creation exists in any form of design. It is practically impossible to design in the void without any restrictions, and all design is based on preceding examples. This is because production of artificial is based on the universal principles or structure residing in history, namely, typology. Considering Digital Space from technological and cultural standpoints, it can obviously be called a new type of space, and beyond that, it becomes a new type of a methodological tool of design. Thus, the purpose of this study is to systematize the paradigm of the space design in the digital era by studying the concept of space in Digital Space from the standpoints of history and context, that is typology, and in accordance with it, classify the phases of the space design that is led digitally.at is led digitally.

• Journal of IKEEE
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• v.23 no.3
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• pp.988-993
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• 2019

Over the past decades, the semiconductor industry has continuously scaled down the size of semiconductor devices to increase those performance and to integrate them at higher density on the chip. However, facing the reduction of gate control, higher leakage current, and short channel effect, there is a growing interest in next-generation semiconductors which can overcome these problems. In this paper, we discuss digital circuit design techniques using CNTFET(Carbon NanuTube Field Effect Transistor), which are attracting attention as candidates for the next generation of semiconductors. Since the structure of CNTFETs are clearly different from the structure of the structure of conventional MOSFETs, we will discuss how to utilize existing digital circuit methodology when designing digital circuits using the CNTFETs, and then simulate the performance differences between the two devices.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.1
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• pp.10-18
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• 2022

Since High Sierra, APFS has been used as the main file system. It is a well-established file system that has been used stably thus far. From the perspective of digital forensics, there are still many areas to be investigated. Apple File System Reference is provided to the apple developer site, but it is not satisfactory to fully analyze APFS. Researchers know more about the structure of APFS than before, but they have not yet fully analyzed its structure to a perfect level about it. In this paper, we develop APFS object identification tool for digital forensics. The most basic and essential object identification and analysis of the APFS filesystem will be conducted with the tool. The analysis in this study serves as the background for an analysis of the checkpoint operation principle and structure, including the more complex B-tree structure of APFS. There are several options for the developed tool, but the results of two use cases will be shown here. Based on the implemented tool, it is hoped that more functions will be added to make APFS a useful tool for faster and more accurate analyses.

• IE interfaces
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• v.23 no.1
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• pp.68-77
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• 2010

Digital reactor protection system which consists of many identical modules, is fault- tolerant to provide high safety. The modules themselves including DSP(digital signal processing) card are also fault-tolerant in nature. This paper assesses the safety for being-designed digital reactor protection system of 2-out-of-4 G structure with lockout. Some interesting design alternatives are compared. Fault tree analysis for assessing system safety is performed by Relex software. The selected reactor protection system fully satisfies EPRIURD stipulation of mean failure time of 50 years.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.4 no.4
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• pp.264-271
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• 2011

ILS(Instrument Landing System) is the international standard system for approach and landing guidance. ILS was adopted by ICAO(International Civil Aviation Organization) in 1947 and is currently being used in commercial systems. To design the digital transmitter and receiver modules that can be mounted in the integrated ILS, we propose the digital design methods of digital double AM modulator and demodulator using FPGA chip, DDS(Direct Digital Synthesizer) for generation of sampling clock, demodulator of DDC(Digital Down Converter) structure, and spectrum analyzer using DSP chip. We demonstrate the efficiency of the proposed design method through experiments using developed transmitter and receiver modules. This system can be used as a high-performance commercial system.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1155-1158
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• 2007

To reduce acoustic noise level of an AV projector, primary noise sources of AV projector were analyzed. Based on the analyzed result, methods to control each source are presented and tried. Structure-borne noise can be controlled by anti vibration design of mounting system, and air-borne noise by reducing flow resisitvity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.03b
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• pp.3-3
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• 2010

The Characteristics of Digital Vterbi Decoder utilizing the analog parallel processing circuit technology is proposed. The Analog parallel structure of the viterbi decoder acted by a replacement of the conventional digital viterbi Decoder is progressing fastly. The proposed circuits design han, low distortion, high accuracy over the previous implementation and dynamic programming.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.1
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• pp.1-5
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• 2002

A common way to design a digital control system is to design an analog controller first and discretize it for digital implemention. In this paper, optimal digital controller design is studied within the framework of sampled -data control theory. In particular, multirate discretization of analog controller is considered using an Η$_2$optimality criterion. Solutions are obtained via multirate H2 optimization with a causality constraint due to the multirate structure. In design example, the comparison of the proposed methods is made with the conventional discretization methods, and demonstrate the superiority of the multirate design method.