• Title/Summary/Keyword: kernel development

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Development of WLAN AP based on IBM 405GP (IBM PowerPC 405GP를 이용한 Wireless LAN Access Point 개발에 관한 연구)

  • Kim Do-Gyu
    • The Journal of Information Technology
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    • v.6 no.3
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    • pp.65-73
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    • 2003
  • The evaluation AP embedded Linux board is implemented. The board is made of IBM 405 GP processor, PPCBoot-1.2.1 boot loader, Linux-2.4.21 kernel and root file system. The evaluation board has two flash memories, boot flash and application flash of size 512Kbyte and 16Mbyte, respectively. And it supports IEEE 802.11a which provide the maximum throughput of 54Mbps in the 5.2GHz frequency band. MTD(Memory Technology Device) and JFFS2(Journalling Flash File System version 2) technologies are adopted to optimally package the system software, boot loader, kernel and root file system. And in order to optimize root file system, busybox package and tiny login are used. Linux kernel and root file system is combined together with mkimage utility.

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A Development of Lagrangian Particle Dispersion Model (Focusing on Calculation Methods of the Concentration Profile) (라그란지안 입자확산모델개발(농도 계산방법의 검토))

  • 구윤서
    • Journal of Korean Society for Atmospheric Environment
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    • v.15 no.6
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    • pp.757-765
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    • 1999
  • Lagrangian particle dispersion model(LPDM) is an effective tool to calculate the dispersion from a point source since it dose not induce numerical diffusion errors in solving the pollutant dispersion equation. Fictitious particles are released to the atmosphere from the emission source and they are then transported by the mean velocity and diffused by the turbulent eddy motion in the LPDM. The concentration distribution from the dispersed particles in the calculation domain are finally estimated by applying a particle count method or a Gaussian kernel method. The two methods for calculating concentration profiles were compared each other and tested against the analytic solution and the tracer experiment to find the strength and weakness of each method and to choose computationally time saving method for the LPDM. The calculated concentrations from the particle count method was heavily dependent on the number of the particles released at the emission source. It requires lots fo particle emission to reach the converged concentration field. And resulting concentrations were also dependent on the size of numerical grid. The concentration field by the Gaussian kernel method, however, converged with a low particle emission rate at the source and was in good agreement with the analytic solution and the tracer experiment. The results showed that Gaussian kernel method was more effective method to calculate the concentrations in the LPDM.

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An efficient microscopic technique for aleurone observation with an entire kernel cross-section in maize (Zea mays L.)

  • Jae-Hong Kim;Ji Won Kim;Gibum Yi
    • Korean Journal of Agricultural Science
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    • v.50 no.4
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    • pp.645-652
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    • 2023
  • The aleurone layer in maize is crucial as it contains essential nutrients such as minerals, vitamins, and high-quality proteins. While most of the maize varieties are known to possess a single aleurone layer, several multi-aleurone layer mutants and landraces have been suggested for hierarchical genetic control of aleurone development. Conventional microscopy analysis often involves using immature seeds or sampling only a portion of the kernel sample, and whole kernel section analysis using a microtome is technically difficult and time-consuming. Additionally, the larger size of maize kernels posed challenges for comprehensive cross-sectional analysis compared to other cereal crops. Consequently, this study aimed to develop an efficient method to comprehensively understand the aleurone layer characteristics of the entire cross-section in maize. Through observations of diverse maize genetic resources, we confirmed irregular aleurone layer patterns in those with multiple aleurone layers, and we discovered a landrace having multiple aleurone layers. By selectively identifying genetic resources with multiple aleurone layers, this method may contribute to efficient breeding processes in maize.

Nondestructive Measurement of the Coating Thickness in the Simulated TRISO-Coated Fuel Particle Using Micro-Focus X-ray Radiography (마이크로포커스 X-선 투과 영상을 이용한 모의 TRISO 핵연료 입자 코팅 층 두께 비파괴 측정)

  • Kim, Woong-Ki;Lee, Young-Woo;Park, Ji-Yeon;Park, Jung-Byung;Ra, Sung-Woong
    • Journal of the Korean Society for Nondestructive Testing
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    • v.26 no.2
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    • pp.69-76
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    • 2006
  • TRISO(tri-isotropic)-coated fuel particle technology is utilized owing to its higher stability at a high temperature and Its efficient retention capability for fission products In the HTGR(high temperature gas-reeled reactor). The typical spherical TRISO fuel panicle with a diameter of about 1mm is composed of a nuclear fuel kernel and outer coating layers. The outer coating layers consist of a buffer PyC(pyrolytic carbon) layer, Inner PyC(1-PyC) layer, SiC layer, and outer PyC(O-PyC) layer Most of the Inspection Items for the TRTSO-coated fuel particle depend on destructive methods. The coating thickness of the TRISO fuel particle can be nondestructively measured by the X-ray radiography without generating radioactive wastel. In this study, the coaling thickness for the simulated TRISO-coated fuel particle with $ZrO_2$ kernel Instead of $%UO_2$ kernel was measured by using micro-focus X-ray radiography with micro-focus X-ray generator and flat panel detector The radiographic image was also enhanced by image processing technique to acquire clear boundary lines between coating layers. The coaling thickness wat effectively measured by applying the micro-focus X-ray radiography The inspection process for the TRISO-coated fuel particles will be improved by the developed micro-focus X-ray radiography and digital image processing technology.

An Implementation and Performance Analysis of IPC Mechanism in M3K : A Multimedia Micro-Kernel (멀티미디어 마이크로 커널 M3K에서 프로세스간 통신 구현 및 성능 분석)

  • Kim, Young-Ho;Ko, Young-Woong;Ah, Jae-Yong;Yoo, Hyuck
    • Journal of KIISE:Computer Systems and Theory
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    • v.29 no.3
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    • pp.143-152
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    • 2002
  • As the multimedia application becomes ubiquitous, the size of message used for Inter Process Communication (IPC) grows up to cope with the requirements of multimedia applications. And the rapid development of new hardware platforms makes the portability of operating system more important. But the traditional micro-kernel operating system is Implemented platform dependently for better performance, and especially focused on handling short message. In this paper, we present the design and implementation of IPC mechanism in M3K (MultiMedia Micro-Kernel) to address the above problems. Our IPC mechanism provides enhanced performance and efficiently handles large message without performance degrading.

Development of a Rapeseed Reaping Equipment Attachable to a Conventional Combine (II) - Evaluation of Feasibility in Rapeseed Harvesting - (보통형 콤바인 부착용 유채 예취장치 개발(II) - 유채 수확 적응성 평가 -)

  • Lee, Choung-Keun;Choi, Yong;Jang, Young-Seok;Jung, Young-Su;Lee, Seung-Kyu;Lee, Wang-Don
    • Journal of Biosystems Engineering
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    • v.34 no.1
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    • pp.21-29
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    • 2009
  • A rapeseed reaping equipment attachable to a conventional combine was developed in order to harvest rapeseed for bio-diesel materials. This study was carried out to measure the harvest feasibility of a prototype combine in rapeseed fields. Grain, stem and pod flow rate, grain qualities (whole kernel, damaged kernel, unhulled kernel, material-other-than-grain) and grain loss rates (header, threshing, separation) were investigated in each field test. As the result of the fold test, the average grain flow rates of SUNMANG and MS varieties showed 1,430 kg/h and 2,038 kg/h, respectively. The average stem and pod flow rates showed 3,443 kg/h and 6,596 kg/h, respectively. In each working speed, the average whole kernel rate and the material-other-than-grain showed 99.9% and below 0.08%, respectively. In the average grain loss, the rates showed 5.66% in case of SUNMANG and 5.94% in MS. Header loss was higher than other parts for SUNMANG. However, threshing loss was relatively higher than other parts for MS. Header loss rate due to side cutter knifes, however, was not so high when compared with a grain loss due to the cutter bar. Effective field capacity and field efficiency of the prototype combine showed 0.389 ha/h and 44%, respectively. Comparison of customary combine with the prototype combine through field test demonstrated that the header loss was reduced by 69.3% when the prototype combine was used.

Design and Implementation of An Object-Oriented Kernel Framework Reusable for the Development of Real-Time Embedded Multitasking Kernels (실시간 내장 멀티태스킹 커널의 개발에 재사용 가능한 객체지향 커널 프레임워크의 설계 및 구현)

  • Lee, Jun-Seob;Jeon, Tae-Woong;Lee, Sung-Young
    • Journal of KIISE:Computing Practices and Letters
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    • v.6 no.2
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    • pp.173-186
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    • 2000
  • Real-time embedded systems should accommodate many kinds of hardware platforms and resource management policies that vary depending on their operating environments and purposes. It is not an easy job to adapt a multitasking kernel to new system services and hardware platforms, as the kernel must strictly satisfy constraints on its size and performance. This paper describes the design and implementation of an object-oriented multitasking framework that can be reused for implementing microprocessor-based real-time embedded multitasking kernels, In this kernel framework, those parts that can vary depending on hardware platforms and system resource management policies are separated into the hot spots and encapsulated by abstract classes. Our framework thus can be effectively used to implement microprocessor-based real-time embedded kernels that demand high portability and adaptability.

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Anisotropic Diffusion based on Directions of Gradient (기울기 방향성 기반의 이방성 확산)

  • Kim, Hye-Suk;Kim, Gi-Hong;Yoon, Hyo-Sun;Lee, Guee-Sang
    • The Journal of the Korea Contents Association
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    • v.8 no.11
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    • pp.1-9
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    • 2008
  • Thanks to the multimedia technology development, it is possible to show image representations in high quality and to process images in various ways. Anisotropic diffusion as an effective diffusion filtering among many image preprocessing methods and postprocessing methods is used in reduction of speckle noises of ultrasound images, image restoration, edge detection, and image segmentation. However, the conventional anisotropic diffusion based on a cross-kernel causes the following problems. The problem is the concentration of edges in the vertical or horizontal directions. In this paper, a new anisotropic diffusion transform based on directions of gradient is proposed. The proposed method uses the eight directional square-kernel which is an expanded form of the cross-kernel. The proposed method is to select directions of small gradient based on square-kernel. Therefore, the range of proposed diffusion is selected adaptively according to the number of the directions of gradient. Experimental results show that the proposed method can decrease the concentration of edges in the vertical or horizontal directions, remove impulse noise. The image in high quality can be obtained as a result of the proposed method.

Changes in Protein, Rheology and Bread-Making Properties of Wheat during Kernel Maturation (소맥(小麥)의 성숙(成熟)에 따른 단백질(蛋白質), 리올로지 및 제(製)빵특성(特性)의 변화(變化))

  • Chang, Hak-Gil;Byoun, Kwang-Eui
    • Applied Biological Chemistry
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    • v.28 no.4
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    • pp.278-283
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    • 1985
  • These studies were conducted to investigate the changes and relation in protein, rheology and bread-mating properties during hard and soft wheat maturation. Samples were collected from the fields at 25 to 50 days after heading at intervals of 5 days. Protein content, sedimentation value and Pelshenke value of the tested wheat kernel or flour differed significantly between hard and soft wheat, and was relatively constant at 35 to 40 days after heading in each cultivar. In Mixogram water absorption of the flour, soft wheat increased only slightly, while intermediate and hard wheat increased remarkedly with maturation of the kernel. Total Mixogram characteristics increased and reached its maximum level at 35 days after heading. Farinogram pattern and bread loaf volume of the flour was greatly differences at the early stages of development due to cultivar, and was relatively constant at 40 days after heading. Significant positive and negative correlations were obtained among the protein and rheological properties, and tread loaf volume as the kernel matured.

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Characteristic Classification and Correlational Analysis of Source-level Vulnerabilities in Linux Kernel (소스 레벨 리눅스 커널 취약점에 대한 특성 분류 및 상관성 분석)

  • Ko Kwangsun;Jang In-Sook;Kang Yong-hyeog;Lee Jin-Seok;Eom Young Ik
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.15 no.3
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    • pp.91-101
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    • 2005
  • Although the studies on the analysis and classification of source-level vulnerabilities in operating systems are not direct and positive solutions to the exploits with which the host systems are attacked, It is important in that those studies can give elementary technologies in the development of security mechanisms. But, whereas Linux systems are widely used in Internet and intra-net environments recently, the information on the basic and fundamental vulnerabilities inherent in Linux systems has not been studied enough. In this paper, we propose characteristic classification and correlational analyses on the source-level vulnerabilities in Linux kernel that are opened to the public and listed in the SecurityFocus site for 6 years from 1999 to 2004. This study may contribute to expect the types of attacks, analyze the characteristics of the attacks abusing vulnerabilities, and verify the modules of the kernel that have critical vulnerabilities.