• Title/Summary/Keyword: Kernel Level

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TTY Device Driver Model of User-Level (사용자 수준의 단말기 구동기 모델)

  • Lee, Hyeong-Ju;Im, Seong-Rak
    • The Transactions of the Korea Information Processing Society
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    • v.2 no.6
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    • pp.815-822
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    • 1995
  • In the conventional UNIX system, the all device driver realized in the kern el. Hence, whenever we want to add a new device driver or change the existin g device driver, the modification of kernel is unavoidable. Generally, it is very difficult to modify the kernel codes.As a method of overcoming this difficulty, a TTY device driver model of user-level is presented in this paper. The basic concept of this model is providing a dynamic reconfiguration of TTY device driver by realizing a user-level server process for TTY device driver. In order to verify the proper y of this model, a prototype of TTY device driver has been realized in the SunOS and Linux environment and evaluated its performance.

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Spatial Distribution of the Levels of Water Pollutants in Han River (수질오염도의 공간적 분포 변화 분석 : 한강 유역을 대상으로)

  • Kim, Kwang-Soo;Kwon, Oh-Sang
    • Environmental and Resource Economics Review
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    • v.18 no.1
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    • pp.105-138
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    • 2009
  • This study investigates the spatial distribution of the degree of water pollutants in Han River using data obtained by the water pollution observation stations. This study estimates a non -parametric kernel density function for each water pollutants, and tests a significant difference between two estimated distribution functions. Next, Generalized Entropy inequality indices are evaluated and this research tests difference of inequality indices between two years using bootstrapping method. Lastly in a dynamic of view, it is analyzed that there are significant changes in the ranking of water pollution level. Estimation results show that the degree of inequality in spatial distribution of water pollution tends to be stable or decreasing for last 15 years in a great part of water pollutants, and ranking of water pollution level hardly changes in Han River.

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Nutritional Evaluation of Imported Organic Feeds and Locally Produced Agricultural By-products for Organic Ruminant Farming (유기 반추동물 전용 수입산 유기사료 및 국내산 유기 부산물의 사료적 가치 평가)

  • Park, Joong-Kook;Kim, Chang-Hyun
    • Korean Journal of Organic Agriculture
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    • v.19 no.4
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    • pp.513-528
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    • 2011
  • This study was conducted to evaluate the nutritional value of locally produced organic agricultural by-products to substitute imported organic feeds for organic ruminant farming. Imported organic feeds (corn grain, soybean meal, soybean seed, oat grain, barley grain, wheat grain, buckwheat, sunflower seed meal) and byproducts (rice bran, grape seed meal, rice straw, soybean hull, soybean curd, rice hull, green kernel rice, and crushed rice grain) were analyzed for chemical composition and NDF, ADF, mineral, and amino acid contents and anti-nutritional factors. Dry matter, NDF and ADF contents in organic feeds were higher than those in conventional feeds. Especially, the 9.65% fat content of organic soybean meal was 6 times higher than the 1.95% fat content of conventional soybean meal. Fat contents of rice bran, grape seed meal, green kernel rice, and crushed rice grain were 25.66, 6.09, 3.57 and 1.59%, respectively. Protein contents of soybean hull and soybean curd were 14.68 and 19.87%, respectively, which are highest among organic by-products. Levels of aflatoxin in all feeds were below the safety level. Therefore, organic rice bran, green kernel rice and crushed rice as energy source, and soybean hull and soybean curd as protein source could partial replace imported feeds for organic ruminant farming.

A design and implementation of DOS-based multitasking Kernel of the real-time operating systems for robot controller (DOS 환경 로봇제어기용 실시간 운영체계를 위한 멀티태스킹 커널의 설계및 구현)

  • Jang, Ho;Lee, Ki-Dong
    • Journal of Institute of Control, Robotics and Systems
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    • v.3 no.4
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    • pp.373-380
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    • 1997
  • In order to implement the real-time operating systems for robot controller, this paper proposes a systematic method for implementing the real-time kernel under the DOS environment. So far, we designed the robot control software and its own operating system simultaneously. Though robot operating systems have simple structure, it allows the developer to have a surplus time and effort to implement complete robot systems. In addition to this, in most cases of this type, operating systems does not support multitasking function, thus, low level hardware interrupts are used for real-time execution. Subsequently, some kinds of real-time tasks are hard to implement under this environment. Nowadays, the operating systems for robot controller requires multitasking functions, intertask communication and task synchronization mechanism, and rigorous real-time responsiveness. Thus, we propose an effective and low costs real-time systems for robot controller satisfying the various real-time characteristics. The proposed real-time systems are verified through real implementation.

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Learning Discriminative Fisher Kernel for Image Retrieval

  • Wang, Bin;Li, Xiong;Liu, Yuncai
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.3
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    • pp.522-538
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    • 2013
  • Content based image retrieval has become an increasingly important research topic for its wide application. It is highly challenging when facing to large-scale database with large variance. The retrieval systems rely on a key component, the predefined or learned similarity measures over images. We note that, the similarity measures can be potential improved if the data distribution information is exploited using a more sophisticated way. In this paper, we propose a similarity measure learning approach for image retrieval. The similarity measure, so called Fisher kernel, is derived from the probabilistic distribution of images and is the function over observed data, hidden variable and model parameters, where the hidden variables encode high level information which are powerful in discrimination and are failed to be exploited in previous methods. We further propose a discriminative learning method for the similarity measure, i.e., encouraging the learned similarity to take a large value for a pair of images with the same label and to take a small value for a pair of images with distinct labels. The learned similarity measure, fully exploiting the data distribution, is well adapted to dataset and would improve the retrieval system. We evaluate the proposed method on Corel-1000, Corel5k, Caltech101 and MIRFlickr 25,000 databases. The results show the competitive performance of the proposed method.

Preventing ELF(Executable and Linking Format)-File-Infecting Malware using Signature Verification for Embedded Linux (임베디드 리눅스에서 서명 검증 방식을 이용한 악성 프로그램 차단 시스템)

  • Lee, Jong-Seok;Jung, Ki-Young;Jung, Daniel;Kim, Tae-Hyung;Kim, Yu-Na;Kim, Jong
    • Journal of KIISE:Computing Practices and Letters
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    • v.14 no.6
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    • pp.589-593
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    • 2008
  • These days, as a side effect of the growth of the mobile devices, malwares for the mobile devices also tend to increase and become more dangerous. Because embedded Linux is one of the advanced OSes on mobile devices, a solution to preventing malwares from infecting and destroying embedded Linux will be needed. We present a scheme using signature verification for embedded Linux that prevents executallle-Infecting malwares. The proposed scheme works under collaboration between mobile devices and a server. Malware detection is delegated to the server. In a mobile device, only integrity of all executables and dynamic libraries is checked at kernel level every time by kernel modules using LSM hooks just prior to loading of executables and dynamic libraries. All procedures in the mobile devices are performed only at kernel level. In experiments with a mobile embedded device, we confirmed that the scheme is able to prevent all executable-Infecting malwares while minimizing damage caused by execution of malwares or infected files, power consumption and performance overheads caused by malware check routines.

Design and Implementation of Kernel Binder Cache for Accelerating Android IPC (안드로이드 IPC 가속화를 위한 커널 바인더 캐쉬의 설계 및 구현)

  • Yeon, Jeseong;Koh, Kern;Lee, Eunji
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.5
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    • pp.33-38
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    • 2016
  • In Android platform, as applications invoke various service functions through IPC (Inter-Process Communication), IPC performance is critical to the responsiveness in Android. However, Android offers long IPC latency of hundreds of micro-seconds due to complicated software stacks between the kernel Binder and the user-level process Context Manager. This separation provides modularity and flexibility, but degrades the responsiveness of services owing to additional context switching and inefficient request handling. In this paper, we anatomize Android IPC mechanisms and observe that 55% of IPC latency comes from the communication overhead between Binder and Context Manager. Based on this observation, this paper proposes a kernel Binder cache that retains a popular subset of service function mappings, thereby reducing the requests transferred to the user-level daemon. The proposed Binder cache is implemented in Android 5.0 and experimental results with various benchmarks show that the proposed cache architecture improves performance by 52.9% on average.

Mechanical Fault Classification of an Induction Motor using Texture Analysis (질감 분석을 이용한 유도 전동기의 기계적 결함 분류)

  • Jang, Won-Chul;Park, Yong-Hoon;Kang, Myeong-Su;Kim, Jong-Myon
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.12
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    • pp.11-19
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    • 2013
  • This paper proposes an algorithm using vibration signals and texture analysis for mechanical fault diagnosis of an induction motor. We analyze characteristics of contrast and pattern of an image converted from vibration signal and extract three texture features using gray-level co-occurrence model(GLCM). Then, the extracted features are used as inputs of a multi-level support vector machine(MLSVM) which utilizes the radial basis function(RBF) kernel function to classify each fault type. In addition, we evaluate the classification performance with varying the parameter from 0.3 to 1.0 for the RBF kernel function of MLSVM, and the proposed algorithm achieved 100% classification accuracy with the parameter of the RBF from 0.3 to 1.0. Moreover, the proposed algorithm achieved about 98% classification accuracy with 15dB and 20dB noise inserted vibration signals.

Probability Density Function of the Tidal Residuals in the Korean Coast (한반도 연안 조위편차의 확률밀도함수)

  • Cho, Hong-Yeon;Kang, Ju-Whan
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.24 no.1
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    • pp.1-9
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    • 2012
  • Tidal residual is being an important factor by the influence of the climate change in terms of the coastal safety and defense. It is one of the most important factor for the determination of the reference sea level in order to check the safety and performance of the coastal structures in company with the typhoon intensity variation. The probability density function (pdf) of tidal residuals in the Korean coasts have a non-ignorable skewness and high kurtosis. It is highly restricted to the application of the normal pdf assumption as an approximated pdf of tidal residuals. In this study, the pdf of tidal residuals estimated using the Kernel function is suggested as a more reliable and accurate pdf of tidal residuals than the normal function. This suggested pdf shows a good agreement with the empirical cumulative distribution function and histogram. It also gives the more accurate estimation result on the extreme values in comparison with the results based on the normal pdf assumption.

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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