• Title/Summary/Keyword: Performance isolation

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An Efficient Kernel Introspection System using a Secure Timer on TrustZone (TrustZone의 시큐어 타이머를 이용한 효율적인 커널 검사 시스템)

  • Kim, Jinmok;Kim, Donguk;Park, Jinbum;Kim, Jihoon;Kim, Hyoungshick
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.25 no.4
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    • pp.863-872
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    • 2015
  • Kernel rootkit is recognized as one of the most severe and widespread threats to corrupt the integrity of an operating system. Without an external monitor as a root of trust, it is not easy to detect kernel rootkits which can intercept and modify communications at the interfaces between operating system components. To provide such a monitor isolated from an operating system that can be compromised, most existing solutions are based on external hardware. Unlike those solutions, we develop a kernel introspection system based on the ARM TrustZone technology without incurring extra hardware cost, which can provide a secure memory space in isolation from the rest of the system. We particularly use a secure timer to implement an autonomous switch between secure and non-secure modes. To ensure integrity of reference, this system measured reference from vmlinux which is a kernel original image. In addition, the flexibility of monitoring block size can be configured for efficient kernel introspection system. The experimental results show that a secure kernel introspection system is provided without incurring any significant performance penalty (maximum 6% decrease in execution time compared with the normal operating system).

A Brief Review on Uncertainty Analysis for the WIPP PA (EPA 규제에 대한 WIPP 사이트 성능평가의 불확실성 분석에 관한 검토)

  • 이연명;강철형;한경원
    • Tunnel and Underground Space
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    • v.12 no.1
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    • pp.52-69
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    • 2002
  • The WIPP (Waste Isolation Pilot Plant), located 42km east of Carlsbad, New Mexico (NM), in bedded salt 655m below the surface, is a mined repository constructed by the US DOE for the permanent disposal of transuranic (TRU) wastes generated by activities related to defence of the US since 1970. Its historical disposal operation began in March 1999 following receipt of a final permit from the State of NM after a positive certification decision for the WIPP was issued by the EPA in 1998, as the first licensed facility in the US for the deep geologic disposal of radioactive wastes. The CCA (Compliance Certification Application) for the WIPP that the DOE submitted to the EPA in 1966 was supported by an extensive performance assessment (PA) carried out by Sandia National Laboratories (SNL), with so-called 1996 PA. Even though such PA methodologies could be greatly different from the way we consider for HLW disposal in Korea largely due to quite different geologic formations in which repository are likely to be located, a review on lots of works done through the WIPP PA studies could be the most important lessons that we can learn from in view of current situation in Korea where an initial phase of conceptual studies on HLW disposal has been just started. The objective of this art report is an overview of the methodology used in the recent WIPP PA to support the US DOE WIPP CCA and some relevant results completed by SNL.

Isolation and Identification of Low Molecular Weight Compounds Produced by Bacillus subtilis HJ927 and Their Biocontrol Effect on the Late Blight of Pepper (Capsicum annuum L.) (Bacillus subtilis HJ927에 의해 생성된 화합물의 분리, 동정 및 고추(Capsicum annum L.) 역병방제 효과)

  • Lee, Hyun-Jin;Park, Keun-Hyung;Shim, Jae-Han;Park, Ro-Dong;Kim, Yong-Woong;Hwang-Bo, Hoon;Cho, Jeung-Yong;Kim, Young-Cheol;Kim, Kil-Yong
    • Korean Journal of Soil Science and Fertilizer
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    • v.38 no.1
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    • pp.25-31
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    • 2005
  • A soil bacterium, Bacillus subtilis HJ927, exhibiting strong antagonistic property against pathogenic fungi was isolated from pepper fields infested with Phytophthora capsici. Pepper plants inoculated with P. capsici revealed severe root mortality while plants co-inoculated with B. subtilis HJ927 and P. capsici showed drastically reduced root mortality. Low molecular weight substances released by B. subtilis HJ927 mediated the plant protective effect. The anti-fungal compounds released by B. subtilis HJ927 were identified as 3-methylbutyric acid, 2-methylbutyric acid, and methyl 2-hydroxy, 3-phenylpropanoate by high-performance liquid chromatography and gas chromatography-mass spectrometry. In addition to these compounds, B. subtilis HJ927 also produced ${\beta}$-1,3-glucanase, a hydrolytic enzyme implicated in antifungal activity.

Isolation and Identification of Low Molecular Volatile Compounds from Ethyl Acetate Layer of Korean Black Raspberry (Rubus coreanus Miq.) Wine (복분자(Rubus coreanus Miquel) 와인의 ethyl acetate 획분으로부터 저분자 휘발성 화합물들의 분리 및 구조해석)

  • Cho, Jeong-Yong;Kim, Seong-Ja;Lee, Hyoung-Jae;Kim, Jin-Young;Lym, Ik-Jae;Kang, Seong-Koo;Park, Keun-Hyung;Moon, Jae-Hak
    • Korean Journal of Food Science and Technology
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    • v.43 no.5
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    • pp.558-563
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    • 2011
  • In the course of our investigation for chemical constituents in the ethyl acetate layer of Korean black raspberry wine, five compounds were isolated and purified by silica gel column chromatography and high-performance liquid chromatography. The isolated compounds were identified as ethyl succinate (1), vanillic acid (2), ethyl 3,4-dihydroxybenzoate (3), furan-2-ol (4), and 4-(4-hydroxyphenyl)butan-2(S)-ol (5) based on the spectroscopic data of electrospray ionization tandem mass spectrometry and nuclear magnetic resonance. The presence of 2 in Korean black raspberry has previously reported. However, 1 and 3-5 in Korean black raspberry and its wine were isolated for the first time.

Isolation and Purification of Garlic Specific Organic Compounds (마늘 특이 유기화합물의 분리 및 정제)

  • Oh, Tae-Young;Kyung, Kyu-Hang
    • Korean Journal of Food Science and Technology
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    • v.43 no.5
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    • pp.553-557
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    • 2011
  • Garlic specific organic compounds were separated and purified using a recycling preparative high-performance liquid chromatography (HPLC) from blanched garlic cloves. Identification of the compounds involved comparing the previously reported HPLC retention times as well as other identification methods including $^1H$- and $^{13}C$-nuclear magnetic resonance and liquid chromatography-mass spectrometry. The yields of garlic specific organic compounds were 12.2, 42.5, 1.6, 1.2, and 4.8% on wet weight basis of garlic for alliin(S-allyl-L-cysteine sulfoxide), isoalliin(S-1-propenyl-L-cysteine sulfoxide), ${\gamma}$-glutamyl-S-allylcysteine, ${\gamma}$-glutamyl-S-1-propenylcysteine and ${\gamma}$-glutamyl-phenylalanine, respectively. All the compounds, except for ${\gamma}$-glutamylphenylalanine, contained sulfur.

The method of development for enhancing reliability of missile assembly test set (유도탄 점검 장비의 신뢰성 향상을 위한 개발 방법)

  • Koh, Sang-Hoon;Han, Seok-Choo;Lee, Kye-Shin;Lee, You-Sang;Kim, Young-Kuk;Park, Dong-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.8
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    • pp.37-43
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    • 2018
  • A developer solves problems with isolating failures if faults are detected when inspecting missiles using the missile assembly test set (MATS) and then resumes the testing. In order to identify faults, it is necessary to analyze the data coming from the equipment, but the information received may not be sufficient, depending on the inspection environment. In this case, the developer repeats the test until the problem is reproduced or checks the performance of each piece of equipment that is related to the fault. When this task is added, schedule management becomes problematic, and development costs rise. To solve this problem, we need to design a MATS in a systematic way to increase fault coverage while satisfying the required reliability. By designing the necessary processes for each procedure, it is possible to reduce the fault identification time when a fault is detected during operations. But it is not possible to guarantee 100% fault coverage, so we provide another method by comparing costs and effects. This paper describes a development method to enhance the reliability of the missile assembly test set; it describes the expected effects when it is adapted, and describes the limitations of this method.

Analysis of Mission Statement of Social Welfare Centers (사회복지관의 조직 사명문 분석)

  • Kwon, Sun-ae;Kim, Sun-joo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.11
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    • pp.425-432
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    • 2017
  • The purpose of this study is to analyze mission statements of social welfare centers. For this, we collected mission statements of 385 social welfare centers nationwide. We analyzed data using the NVivo 10 program. Analysis results found the total number of collected words was 1,401. The number of words corresponding to the target of organizations was 448 (32.0%), the number of words corresponding to problems was 51 (3.6%), the number of words corresponding to the directionality 118 (8.4%), the number of words corresponding to strategy was 545 (38.9%), and the number of words corresponding to organization's image was 239 (17.1%). Second, the words of the intervention target were resident of community, local community and community. Intervention issues included community problems, poverty, and social isolation. The words of the organizational directivity included welfare community/village, social welfare, and empowerment. Words related to organizational strategy were formation/building, sharing/serving, and improvement/development/improvement. Words related to the organizational image included in the mission statements were the welfare center, we, the professional agency, and the neighbors. By analyzing the mission statements, we found that social welfare centers portrayed its identity based on 'locality'. The distribution of the words related to the community was high in both the target, target, and direction. The limitations of this study include the exclusion of analyzing the relationship between organizational mission and organizational performance. This should be considered in future studies.

Isolation of Bacillus subtilis GS-2 Producing γ-PGA from Ghungkukjang Bean Paste and Identification of γ-PGA (청국장으로부터 분리한 Poly(γ-glutamic acid)를 생산하는 균주 Bacillus subtilis GS-2의 분리 및 γ-PGA의 확인)

  • Bang, Byung-Ho;Jeong, Eun-Ja;Rhee, Moon-Soo;Kim, Yong-Min;Yi, Dong-Heui
    • Journal of Applied Biological Chemistry
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    • v.54 no.1
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    • pp.1-6
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    • 2011
  • ${\gamma}$-PGA(poly-${\gamma}$-glutamic acid) is an unusual anionic polypeptide that is made of D- and L-glutamic acid units connected by amide linkages between ${\alpha}$-amino and ${\gamma}$-carboxylic acid groups. ${\gamma}$-PGA has been isolated from many kinds of organisms. Many Bacillus strains produce ${\gamma}$-PGA as a capsular material of an extracellular viscous material. It is safe for eating as a viscosity element of fermented soybean products such as Chungkookjang and Natto. It is biodegradable, edible and nontoxic toward humans and the environment and its molecular weight varies from ten thousand to several hundred thousand depending on the kinds of strains used. Therefore, potential applications of ${\gamma}$-PGA and its derivatives have been of interest in the past few years in a broad range of industrial fields such as food, cosmetics, medicine, water-treatment, etc. In this study, a bacterium, Bacillus subtilis GS-2 isolated from the Korean traditional seasoning food, Chungkookjang could produce a large amount of ${\gamma}$-PGA with high productivity and had a simple nutrient requirement. Based on carbon utilization pattern and partial 16S rRNA sequence analysis, the GS-2 strain was identified as B. subtilis. The determination of purified ${\gamma}$-PGA was confirmed with thin layer chromatography (TLC), high performance liquid chromatography (HPLC), fourier transform infrared (FT-IR) spectra, and $^1H$-nuclear magnetic resonance ($^1H$-NMR) spectroscopy.

ISOLATION, IDENTIFICATION AND CHARACTERIZATION OF AN IMMOBILIZED BACTERIUM PRODUCING N2 FROM NH4+ UNDER AN AEROBIC CONDITION

  • Park, Kyoung-Joo;Cho, Kyoung-Sook;Kim, Jeong-Bo;Lee, Min-Gyu;Lee, Byung-Hun;Hong, Young-Ki;Kim, Joong-Kyun
    • Environmental Engineering Research
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    • v.10 no.5
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    • pp.213-226
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    • 2005
  • To treat wastewater efficiently by a one-step process of nitrogen removal, a new bacterial strain producing $N_2$ gas from ${NH_4}^+$ under an aerobic condition was isolated and identified. The cell was motile and a Gram-negative rod, and usually occurred in pairs. By 16S-rDNA analysis, the isolated strain was identified as Enterobacter asburiae with 96% similarity. The isolate showed that the capacity of $N_2$ production under an oxic condition was approximately three times higher than that under an anoxic condition. Thus, the consumption of ${NH_4}^+$ by the isolate was significantly different in the metabolism of $N_2$ production under the two different environmental conditions. The optimal conditions of the immobilized isolate for $N_2$ production were found to be pH 7.0, $30^{\circ}C$ and C/N ratio 5, respectively. Under all the optimum reaction conditions, $N_2$ production by the immobilized isolate resulted in reduction of ORP with both the consumption of DO and the drop of pH. The removal efficiencies of $COD_{Cr}$, and TN were 56.1 and 60.9%, respectively. The removal rates of $COD_{Cr}$, and TN were the highest for the first 2.5 hrs with the removal $COD_{Cr}/TN$ ratios of 32.1, and afterwards the rates decreased as reaction proceeded. For application of the immobilized isolate to a practical process of ammonium removal, a continuous operation was executed with a synthetic medium of a low C/N ratio. The continuous bioreactor system exhibited a satisfactory performance at 12.1 hrs of HRT, in which the effluent concentrations of ${NH_4}^+$-N was measured to be 15.4 mg/L with its removal efficiency of 56.0%. The maximum removal rate of ${NH_4}^+$-N reached 1.6 mg ${NH_4}^+$-N/L/hr at 12.1 hrs of HRT(with N loading rate of $0.08\;Kg-N/m^3$-carrier/d). As a result, the application of the immobilized isolate appears a viable alternative to the nitrification-denitrification processes.

A Study on Mastitis Infection Rate and Investigation of Milk Contamination Level by Measuring the Bacteria and Somatic Cell Counts in Gyunggi Area (京畿一圓 乳牛의 乳房炎 感染率과 原乳의 細菌 및 體細胞數 測定에 따른 乳質 汚染度에 관한 연구)

  • Eu, Byung Woo
    • Journal of Environmental Health Sciences
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    • v.11 no.2
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    • pp.41-54
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    • 1985
  • This study was conducted for the improvement of milk quality and milk hygiene in public health point of view. Investigation of mastiris infection rate, isolation and identification of causative microorganisms in CMT positive milk, investigation of milk contamination level by measuring the bacteria and soma tic cell counts and investigation of dairy management in farms were performed on 1.605 quarters milk of 434 cows of 20 dairy farms in Gyunggi-area from September 1983 to March 1984. The results were summarized as follows 1. Sixteen (3.7%) of 434 cows were found to be infected with clinical mastiris. 234 (53.9%) of 434 cows and 608(37.9%) of 1, 605 quarters were found to be infected with subclinical mastiris. 2. The causative microorganisms isolated were Staphylococcus aureus (38.3%), Staphylococcus epidermidis(21.0%), Micrococci(13.6%), Streptococcus spp. (12.3%), E. coli (7.4%), Fungus & Yeast (1.6%) and others (5.8%). 3. Total numbers of bacteria were $9.2{\times}10^6$ to $1.21{\times}10^7/ml$(av. $1.805{\times} 10^7/ml$), numbers of coliform bacteria were $4.1{\times} 10^5$ to $9.4{\times} 10^5$/ml(av. $7.05{\times} 10^5$/ml) and somatic cell counts were $4.8{\times} 10^5$ to $1.52{\times} 10^6$ cells/ml (av. $9.5{\times} 10^5$cells/ml) in bulk milk. 4. As comparing with CMT score of +, ++ and +++, somatic cell counts were $3.4{\times} 10^5$ to $1.64{\times} 10^6$ cells/ml (av. $6.41{\times} 10^5$cells/ml), $5.4{\times} 10^5$ to $2.75{\times} 10^6$ cells/ml(av. $1.762{\times} 10^6$cells/ml) and $1.97{\times} 10^6$ to $9.75{\times} 10^6$ cells/ml(av. $7.781{\times} 10^6$cells/ml), respectively. 5. In investigation on dairy management, performance of dry cow therapy, teat dipping after milking, disinfection of milking machine at every milking, replacement of milk liner within 6months and opportunity of acquirement for the mastiris control techniques by dairy education were 65%, 40%, 45%, 55% and 50% in 20 dairy farms, respectively.

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