• Title/Summary/Keyword: CPA method

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Toxin Gene Typing, DNA Fingerprinting, and Antibiogram of Clostridium perfringens Isolated from Livestock Products

  • Lee, Seung-Bae;Choi, Suk-Ho
    • Food Science of Animal Resources
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    • v.26 no.3
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    • pp.394-401
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    • 2006
  • Forty Clostridium perfringens isolates were obtained from twelve animal products, following the examination of eighty six beef, pork, broiler chicken and salami meat products, and eleven milk powder products. There were 21 isolates from salami stored at $25^{\circ}C$, 3 isolates from pork, 4 isolates from beef, 9 isolates from broiler chicken, and 3 isolates from milk powder. Only the cpa gene encoding a toxin among the 5 toxin genes tested (cpa, cpb, etx, iap, and cpe) was detected in all forty isolates, suggesting contamination with C. perfringens type A. DNA fingerprinting analysis using PCR of the tRNA intergenic spacer (tDNA-PCR) and the 16S-23S internal transcribed spacer (ITS-PCR), and randomly amplified polymorphic DNA (RAPD) analysis were attempted to differentiate the isolates. RAPD analysis was the most discriminating method among the three PCR analyses. Isolates from the same products tended to show similar RAPD patterns. Antimicrobial susceptibility tests showed that some isolates from broiler chickens had the same antibiogram with multiple resistance to streptomycin, colistin, and ciprofloxacin. Antibiograms were similar between isolates from the same livestock products, but differed considerably between the products.

Sedative Activity of Aporphine and Cyclopeptide Alkaoids Isolated from the Seeds of Zizyphus Vulgaris var. Spinosus, and the Fruits and Stem Bark of Zizyphus Jujuba var. Inermis in mice (산조인 및 대추, 대추나무로부터 단리한 아포르핀과 환상 펩티드 알칼로이드의 생쥐에 대한 진정작용)

  • 한병훈;박명환;한용남
    • YAKHAK HOEJI
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    • v.37 no.2
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    • pp.143-148
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    • 1993
  • The objective of this study was to evaluate the sedative activity of four aporphine alkaloids (APA) and nine cyclopeptide alkaloids(CPA), which had been isolated from the seeds (sanjoin) of Zizyphus vulgaris var. spinosus, and the fruits and stem bark of Zizyphus jujuba var. inermis. The assessment of sedative activity was carried out, employing a hexobarbital-induced sleeping time method in mice. When the relative sedative potency of sanjoinine-A(CPA) was given as one unit, those of nuciferine (APA), lysicamine (APA), chlorpromazine (positive control), and sanjoinine -Ahl (an epimer of sanjoinine-A) were 13, 6.5, 5, and 3, respectively. The sedatvie activities of other CPAs were much lower than those of sanjoinine-A and -Ahl, and other APAs were not active. On heat treatment, nuciferine and lysicamine were degraded into some artifacts which exhibited no sedative activity, while sanjoinine-A was converted into sanjoinine-Ahl which showed more potent sedative activity. These results suggested that nuciferine and sanjoinine-A were major sedative components of native sanjoin, and that sanjoinine-A and its epimeric artifact, sanjoinineAhl were the active principles of roasted sanjoin. It provides a scientific basis for heat-processing (roasting) of this Oriental medicine.

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The Lung Expression of Proinflammatory Cytokines, TNF-$\alpha$ and Interleukin 6, in Early Periods of Endotoxemia (내독소혈증 유발 급성폐손상에서 폐장내 Proinflammatory Cytokines 발현에 관한 고찰)

  • Moon, Seung-Hyug;Kim, Yong-Hoon;Park, Choon-Sik;Lee, Shin-Je
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.3
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    • pp.553-564
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    • 1998
  • Background: The immediate hoot response to LPS is the production of proinflammatory cytokines that act as intercellular mediators in inflammatory reactions, including acute lung injury. These "early response" cytokines transmit signals from recognition cells to target or effector cells. This host response is further amplified by the expression of leukocyte chemoattractants, growth factors, and adhesion molecules, resulting in an array of proinflammatory events. This experiment was performed to define the lung origin of proinflammatory cytokines, such as TNF-$\alpha$, IL 6 in early periods of endotoxin induced acute lung injury (ALI). Method: The healthy male Sprague-Dawley, weighted 150 - 250g, were divided into saline control (NC) and endotoxemia-induced ALI (ETX-), and leukopenic endotoxemia-induced ALI (CPA-ETX-Group) which was induced by cyclophosphamide, 70 mg/kg i.p. injection. Acute lung injury was evoked by LPS, 5 mg/kg, intravenously administered. Bronchoalveolar lavage was performed at 0, 3, 6 h after LPS-treated to estimate the influx of phagocytes and concentration of total protein, and cytokines as TNF-$\alpha$ and IL 6 by a bioassy using MIT method. We also examined the localization of TNF-$\alpha$ and IL 6 protein in endotoxemia-challenged lung tissue by immunohistochemical stain (IH). Results: The total cell, macrophage and PMN count in BALF were elavated in ETX group compared to NC(p<0.05). In CPA-ETX group, total cell and macrophage count in BALF were not changed compared to NC. but PMN count was markedly reduced and it took part in less than 0.1 % of total BAL cells (p<0.01). The protein concentration in BALF were significantly increased in ETX and CPA-ETX group Compared to NC (p<0.05), but there was significant difference between ETX- and CPA-ETX group only at 6 h (p<0.05). This observation suggested that even if PMNs are involved in the pathogenesis of acute lung injury, their role cannot be viewed as essential The concentration of TNF-$\alpha$ and IL 6 in BALF was significantly increased in the ETX- and CPA-ETX group compared to NC. There was no difference between ETX- and CPA-ETX group. In IH, anti-TNF-$\alpha$- and anti-IL 6 antibody was strongly localized at interstitial monocytes and alveolar macrophages in endotoxemia-challenged lung tissue. From above point of view, activated alveolar macrophage/monocyte considered as a prominent source of proinflammatory cytokines in endotoxemia-challenged lung injury. Conclusion: The prominent source of proinflammatory cytokines in early periods of endotoxemia-induced lung injury will be the activated resident macrophages like an alveolar macrophage and interstitial monocytes. The pulmonary macrophage/monocyte will impact the initiation and continuance of lung injury without PMNs's certain inflammatory role, particularly in endotoxemia-induced acute lung injury.

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Reverse Engineering of Deep Learning Network Secret Information Through Side Channel Attack (부채널 분석을 이용한 딥러닝 네트워크 신규 내부 비밀정보 복원 방법 연구)

  • Park, Sujin;Lee, Juheon;Kim, HeeSeok
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.32 no.5
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    • pp.855-867
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    • 2022
  • As the need for a deep learning accelerator increases with the development of IoT equipment, research on the implementation and safety verification of the deep learning accelerator is actively. In this paper, we propose a new side channel analysis methodology for secret information that overcomes the limitations of the previous study in Usenix 2019. We overcome the disadvantage of limiting the range of weights and restoring only a portion of the weights in the previous work, and restore the IEEE754 32bit single-precision with 99% accuracy with a new method using CPA. In addition, it overcomes the limitations of existing studies that can reverse activation functions only for specific inputs. Using deep learning, we reverse activation functions with 99% accuracy without conditions for input values with a new method. This paper not only overcomes the limitations of previous studies, but also proves that the proposed new methodology is effective.

Efficient Key Detection Method in the Correlation Electromagnetic Analysis Using Peak Selection Algorithm

  • Kang, You-Sung;Choi, Doo-Ho;Chung, Byung-Ho;Cho, Hyun-Sook;Han, Dong-Guk
    • Journal of Communications and Networks
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    • v.11 no.6
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    • pp.556-563
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    • 2009
  • A side channel analysis is a very efficient attack against small devices such as smart cards and wireless sensor nodes. In this paper, we propose an efficient key detection method using a peak selection algorithm in order to find the advanced encryption standard secret key from electromagnetic signals. The proposed method is applied to a correlation electromagnetic analysis (CEMA) attack against a wireless sensor node. Our approach results in increase in the correlation coefficient in comparison with the general CEMA. The experimental results show that the proposed method can efficiently and reliably uncover the entire 128-bit key with a small number of traces, whereas some extant methods can reveal only partial subkeys by using a large number of traces in the same conditions.

High Speed Modular Multiplication Algorithm for RSA Cryptosystem (RSA 암호 시스템을 위한 고속 모듈라 곱셈 알고리즘)

  • 조군식;조준동
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.3C
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    • pp.256-262
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    • 2002
  • This paper presents a novel radix-4 modular multiplication algorithm based on the sign estimation technique (3). The sign estimation technique detects the sign of a number represented in the form of a carry-sum pair. It can be implemented with 5-bit carry look-ahead adder. The hardware speed of the cryptosystem is dependent on the performance modular multiplication of large numbers. Our algorithm requires only (n/2+3) clock cycle for n bit modulus in performing modular multiplication. Our algorithm out-performs existing algorithm in terms of required clock cycles by a half, It is efficient for modular exponentiation with large modulus used in RSA cryptosystem. Also, we use high-speed adder (7) instead of CPA (Carry Propagation Adder) for modular multiplication hardware performance in fecal stage of CSA (Carry Save Adder) output. We apply RL (Right-and-Left) binary method for modular exponentiation because the number of clock cycles required to complete the modular exponentiation takes n cycles. Thus, One 1024-bit RSA operation can be done after n(n/2+3) clock cycles.

Modified Multi-Chaotic Systems that are Based on Pixel Shuffle for Image Encryption

  • Verma, Om Prakash;Nizam, Munazza;Ahmad, Musheer
    • Journal of Information Processing Systems
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    • v.9 no.2
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    • pp.271-286
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    • 2013
  • Recently, a pixel-chaotic-shuffling (PCS) method has been proposed by Huang et al. for encrypting color images using multiple chaotic systems like the Henon, the Lorenz, the Chua, and the Rossler systems. All of which have great encryption performance. The authors claimed that their pixel-chaotic-shuffle (PCS) encryption method has high confidential security. However, the security analysis of the PCS method against the chosen-plaintext attack (CPA) and known-plaintext attack (KPA) performed by Solak et al. successfully breaks the PCS encryption scheme without knowing the secret key. In this paper we present an improved shuffling pattern for the plaintext image bits to make the cryptosystem proposed by Huang et al. resistant to chosen-plaintext attack and known-plaintext attack. The modifications in the existing PCS encryption method are proposed to improve its security performance against the potential attacks described above. The Number of Pixel Change Rate (NPCR), Unified Average Changed Intensity (UACI), information entropy, and correlation coefficient analysis are performed to evaluate the statistical performance of the modified PCS method. The simulation analysis reveals that the modified PCS method has better statistical features and is more resistant to attacks than Huang et al.'s PCS method.

Collaboration and Node Migration Method of Multi-Agent Using Metadata of Naming-Agent (네이밍 에이전트의 메타데이터를 이용한 멀티 에이전트의 협력 및 노드 이주 기법)

  • Kim, Kwang-Jong;Lee, Yon-Sik
    • The KIPS Transactions:PartD
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    • v.11D no.1
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    • pp.105-114
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    • 2004
  • In this paper, we propose a collaboration method of diverse agents each others in multi-agent model and describe a node migration algorithm of Mobile-Agent (MA) using by the metadata of Naming-Agent (NA). Collaboration work of multi-agent assures stability of agent system and provides reliability of information retrieval on the distributed environment. NA, an important part of multi-agent, identifies each agents and series the unique name of each agents, and each agent references the specified object using by its name. Also, NA integrates and manages naming service by agents classification such as Client-Push-Agent (CPA), Server-Push-Agent (SPA), and System-Monitoring-Agent (SMA) based on its characteristic. And, NA provides the location list of mobile nodes to specified MA. Therefore, when MA does move through the nodes, it is needed to improve the efficiency of node migration by specified priority according to hit_count, hit_ratio, node processing and network traffic time. Therefore, in this paper, for the integrated naming service, we design Naming Agent and show the structure of metadata which constructed with fields such as hit_count, hit_ratio, total_count of documents, and so on. And, this paper presents the flow of creation and updating of metadata and the method of node migration with hit_count through the collaboration of multi-agent.

Image Classification Method using Independent Component Analysis and Normalization (독립성분해석과 정규화를 이용한 영상분류 방법)

  • Hong, Jun-Sik;Ryu, Jeong-Woong
    • Journal of KIISE:Software and Applications
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    • v.28 no.9
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    • pp.629-633
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    • 2001
  • In this paper, we improve noise tolerance in image classification by combining ICA(Independent Component Analysis) with Normalization. When we add noise to the raw image data the degree of noise tolerance becomes N(0, 0.4) for PCA and N(0, 0.53) for ICA. However, when we use the preprocessing approach the degree of noise tolerance after Normalization becomes N(0, 0.75), which shows the improvement of noise tolerance in classification.

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A New Approach to the Evaluation of Collision Risk using Sech Function (Sech 함수를 이용한 새로운 충돌위험도 평가법)

  • Jeong, Tae-Gweon
    • Journal of Navigation and Port Research
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    • v.27 no.2
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    • pp.103-109
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    • 2003
  • Evaluating the risk of collision quantitatively plays a key role in developing the expert system of navigation and collision avoidance. This study analysed the existing methods of appraising the collision risk, examined the problem that are intrinsic to them, and developed a new approach to its evaluation by using the sech function as an alternative to them. This paper applied the new method in appraising the collision risk and suggested how to decide the safe range of ownship's action.