• The Journal of the Korea Contents Association
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• v.9 no.3
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• pp.9-19
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• 2009

In this paper, we propose a novel hardware architecture to facilitate the applicable SoC chip design of H.264/SVC which has a great deal of advancement in the international standardization in recent. Moreover, a new C-model simulator based on the proposed hardware system will be presented to support optimal SoC circuit development. Since the proposed SVC decoder is consist of some hardware engine for processing of major decoding tools and core processor for software processing, the system is simply implemented with the conventional embedded system. To improve the feasibility and applicability, and reduce the decoder complexity, the hardware decoder architecture is constructed with only the consideration of IPPP structure scalability without using the full B-picture. Finally, we present results of decoder hardware implementation and decoded picture to show the effectiveness of the proposed hardware architecture and C-model simulator.

• Journal of KIISE:Computing Practices and Letters
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• v.10 no.6
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• pp.448-459
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• 2004

Interoperability is an important requirement of portable storage devices that are used to exchange and share data among diverse hosts. However, the required interoperability cannot be provided if different host systems use different file systems. To address this problem, we propose a new type of storage device called FSOC(File System On a Chip) that contains the file system within the storage device. In this paper, we give an example of the design and implementation of a flash memory-based FSOC and propose the performance models of the conventional storage device and the FSOC. We also analyze the performance characteristics of the conventional storage device and the FSOC based on the proposed performance models, and provide several experimental results using real applications that validate the performance models.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.9
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• pp.615-625
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• 2006

Nonvolatile memory technology is evolving continuously and commercial products such as FeRAM and PRAM are now challenging their markets. As NVRAM has properties of both memory and storage, it can store persistent data objects while allowing fast and random access. To utilize NVRAM for general purpose storing of frequently updated data across power disruptions, some essential features of the file system including naming, recovery, and space management are required while exploiting memory-like properties of NVRAM. Conventional file systems, including even recently developed NVRAM file systems, show very low space efficiency wasting more than 50% of the total space in some cases. To efficiently utilize the relatively expensive NVRAM, we design and implement a new extent-based space-thrifty file system, which we call NEBFS (NVRAM Extent-Based File System). We analyze and compare the space utilization of conventional file systems with NEBFS and validate the results with experimental results observed from running the file system implementations on a system with actual NVRAM installed as well as on systems emulating NVRAM. We show that NEBFS has high space efficiency compared to conventional file systems.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.1A
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• pp.19-27
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• 2011

WiBro is a wireless mobile communication system which supports a high data rate and high mobility in anywhere and anytime. Although WiBro system provides multimedia service including data, audio and video services, customers require better service quality in WiBro system. But, many researches have theoretically evaluated the performance of WiBro system without systematic studies by simulation. Therefore, in this paper, we evaluate a performance of WiBro system using OPNET simulator. We analyze system performance according to various modulation and coding schemes, and propose Adaptive Modulation and Coding (AMC) profile to support quality of services for user requirements. Also we evaluate the performance of WiBro system using AMC and Hybrid-Automatic Repeat Request (H-ARQ) technologies, and confirm that the proposed AMC profile can be applied to WiBro system with high performance.

• Membrane Journal
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• v.25 no.5
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• pp.385-390
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• 2015

To determine the pervaporation separation characteristics of IPA/water mixtures, PEI/PDMS hollow fiber membrane module commercialized by Airrane Co. was subjected to both lab and pilot tests. The flux of $0.52kg/m^2h$ and IPA concentration of 68.5% at $25^{\circ}C$ were obtained whereas the $1.368kg/m^2h$ and 61.2% were measured at $55^{\circ}C$. In order to realized the durability of the module, the long-term test (at $50^{\circ}C$) of 100 days has been conducted and as a result, the flux $1.03{\sim}1.15kg/m^2h$ and IPA concentration 61.8~62.5% were maintained with the initial values.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.955-960
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• 2005

Resistance to metronidazole, a key component of therapies against Helicobacter pylori, is common in clinical isolates. Resistance generally requires inactivation of rdxA (HP0954), and sometimes also frxA (HP0642), two related nitroreductase genes. Here we studied the effect of resistance to metronidazole on fitness of the gastric pathogen H. pylori. The effect of metronidazole resistance for H. pylori in culture was assessed first by looking at colonies formed by freshly constructed mutant derivatives of H. pylori strain 26695. Mutations resulting in metronidazole resistance caused premature death of H.pylori in stationary phase, but had no significant effect on early exponential growth. The effect of nitroreductase deficiencies on fitness in vivo was tested by infecting C57BL/6 mice with 1:1 mixtures of SS1 wild type and its isogenic metronidazole resistant derivatives. Inactivation of rdxA caused an inability to colonize mice in SS1 H. pylori strain. Derivatives of a metronidazole resistant strain that survived better in stationary phase, although remaining metronidazole resistant, could again colonize mice. In conclusion, metronidazole resistance diminishes H. pylori's fitness, but their costs can be suppressed by additional mutation.

• Tunnel and Underground Space
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• v.24 no.2
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• pp.176-186
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• 2014

Roughness, aperture and filling material of rock joint are widely considered to affect the hydraulic characteristics of joint. Among these factors, in this study, the joint roughness was examined with artificial joint profiles generated by Monte Carlo simulating on the original profiles suggested by Barton and Choubey(1977). Original profiles and revised profiles were combined to establish flow channel models, in which the hydraulic characteristics were analyzed numerically on the basis of minimum aperture changes and flow channel shapes. Maximum flow rate was identified at the growing point of flow area after passing through minimum aperture generated by the two profiles, and it was resulted that maximum flow rate is inversely proportional to minimum aperture. Maximum flow rate per unit area showed different values because flow channel shapes and minimum aperture locations are different in each model. In flow channel, mechanical aperture showed approximately 1.07 ~ 3.00 times larger than hydraulic aperture. In this study, mechanical and hydraulic aperture were concluded to be closely related to $A_i$ value, and their relations can be denoted by $e_m=0.519A^{0.7169_i}$ and $e_h=0.6182A^{0.239}_i$, respectively.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.8 s.338
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• pp.27-34
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• 2005

In this paper, FPGA It/w and S/W Embedded system for LDM remote control is implemented. XScale CPU is used on developed system and in communcation ethenet and serial is used. CPU interface with H/W LDM rotation and to drive LDM FPGA logic is implemented, to transmit LDM data from long distance command packet is composed, for S/W Embedded linux is used to design linux device driver and linux application program. This S/W is run by module so by loading this module to linu)( file system it can do any movement. Also by compiling Embedded linux to the system it can lower the price of the system. By using this H/W and S/W theory it can be used on any other embedded system.

• The Journal of the Korea Contents Association
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• v.4 no.1
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• pp.1-7
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• 2004

In addition to wired communication technology, wireless communication technology has been driving communication revolution nowadays. Bluetooth technology carries out data/voice communication making pico-net and the various application services are supported by access network connected to public network. This paper presents educational software development of bluetooth protocol stack including HCI, L2CAP, RFCOMM, SDP and profiles including GAP, SPP, GEOP, FTP. This software which supports programming environment of these protocol monitoring and emulation is implemented basically step by step for education based on H connected to the bluetooth device through RS-232-C, UART or USB cable. Application program coded by Visual C is operated over the firmware loaded on the bluetooth device connected to the PC. Additionally ftp and chatting function are developed to enhance educational efficiency.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1997.11a
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• pp.151-156
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• 1997

본 논문은 저비용이면서 정확한 제어를 수행하는 새로운 퍼지 제어기의 VHDL 설계 및 FPGA 구현을 자동적으로 수행하는 통합 개발 환경(IDE : Integrated Development Environment)을 다룬다. 이를 위해 FLC의 자동 설계 및 구현의 전 과정을 하나의 환경 내에서 개발 가능하게 하는 퍼지 제어기 자동 설계 및 구현 시스템 (FLC Automatic Design and Implementation Station :FADIS)을 개발하였는데 이 시스템은 다음 기능을 포함한다. (1) 원하는 퍼지 제어기의 설계 파라메터를 입력받아 이로부터 FLC를 구성하는 각 모듈의 VHDL 코드를 자동적으로 생성한다. (2) 생성된 각 모듈의 VHDL 코드가 원하는 동작을 수행하는지를 Synopsys사의 VHDL Simulator상에서 시뮬레이션을 수행한다. (3) Synopsys사의 FPGA Compiler에 의해 VHDL 코드를 합성하여 FLC의 각 구성 모듈을 얻는다. (4) 합성된 모듈은 Xilinx사의 XactSTep 6.0에 의해 최적화 및 배치, 배선이 이루어진다. (5) 얻어진 Xilinx rawbit 파일은 VCC사의 r2h에 의해 C 언어의 header 파일 형태의 하드웨어 object로 변환된다. (6) 하드웨어 object를 포함하는 응용 제어 프로그램의 실행 파일을 재구성 \ulcorner 능한 FPGA 시스템 상에 다운로드한다. (7) 구현된 FLC의 동작 과정은 구현된 FLC와 제어 target 사이의 상호 통신에 의해 모니터링한다. 트럭 후진 주차 제어에 사용하는 퍼지 제어기 설계 및 구현의 전 과정을 FADIS상에서 수행하여 FADIS가 완전하게 동작하는지를 확인하였다.