• Journal of Communications and Networks
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• 제12권3호
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• pp.201-208
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• 2010

We propose a new notion of metered signatures. Metered signature is an extension of k-times signatures in which a signer can generate only k signatures. However, the restriction of metered signatures can be more elaborate: It can be used k-times every day or to preserve the order of signed messages in some applications. Any violation of this regulation reveals a secret key or the signature on a predetermined message. The applications includes proxy signatures, limited free downloads, and the rating web site. We give two instances of metered signatures: One is based on the computational Diffie-Hellman problem (CDHP) using a bilinear map and the other is based on the RSA problem. In both schemes, the signature and certificate size and the verification cost are constant with respect to k. Further, we show that the proposed metered signatures admit batch verification of many signatures almost at one verification cost with small security loss.

• 한국소음진동공학회논문집
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• 제14권8호
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• pp.675-683
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• 2004

The motor current signature provides an important source of the information for the faults diagnosis of three-phase induction motor. The theoretical principles behind the generation of unique signal characteristics, which are indicative of failure mechanisms, are Presented. The fault detection techniques that can be used to diagnose mechanical Problems, stator and rotor winding failure mechanisms, and air-gap eccentricity are described. A theoretical analysis is presented which predicts the presence of unique signature patterns in the current that are only characteristics of the fault. The predictions are verified by experimental results from a special fault Producing test rig and on-site tests in a steel company. And this study have made new diagnostic algorithm for the operating induction motors with the test results. These developments are including the use of monitoring and analysis of electric current to diagnose mechanical and electrical problems and gave the precise test results automatically.

• 정보보호학회논문지
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• 제28권4호
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• pp.963-974
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• 2018

비트코인과 같은 암호 화폐에 대한 관심이 증대됨에 따라 블록체인 기술은 뛰어난 보안성을 갖춘 분산 원장 플랫폼으로 다양한 응용분야에서 많은 주목을 받고 있다. 그러나 암호 화폐 채굴(Cryptomining) 과정에 대한 취약성으로 인해 타인에게 CPU와 같은 컴퓨터 자원을 몰래 갈취하는 공격인 Cryptojacking이 등장하였다. 그 중에서도 브라우저 기반 Cryptojacking은 사용자의 PC에 설치하는 동작 없이 단순히 웹 사이트를 방문하는 것만으로 공격이 수행된다는 점에서 그 심각성이 증대되고 있다. 현재까지의 Cryptojacking 탐지 시스템은 대부분 시그니처 기반으로 동작하기 때문에, 기존 Cryptomining 코드의 변형이나 새롭게 등장하는 Cryptomining 코드는 탐지하지 못하는 문제점이 존재한다. 이를 극복하기 위하여, 본 논문에서는 알려지지 않은 Cryptojacking 공격에 대한 탐지를 위해 Headless 브라우저를 이용하여 탐지대상 사이트의 공격 여부를 확인하는 동적 Cryptojacking 사이트 탐지 방안을 제안한다. 제안하는 동적 분석 기반 Cryptojacking 탐지 시스템은 기존 시그니처 기반 Cryptojacking 탐지 시스템에서 탐지하지 못하는 새로운 Cryptojacking 사이트를 탐지 할 수 있으며, Cryptomining 코드를 우회하여 호출하거나 난독화하더라도 이를 탐지하는 것이 가능하다.

• 한국소음진동공학회논문집
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• 제12권4호
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• pp.287-293
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• 2002

The unexpected failure of the induction motor makes the downtime of production, and the cost of the process cessation enormous. To reduce the downtime and increase the reliability of the motor, the vibration measurements for the fault detection have been used previously. Recently motor current signature analysis(MCSA) has been adapted for the fault detection and diagnosis of the motors. MCSA provides a powerful analysis tool for detecting the presence of mechanical and electrical faults in both the motor and driven equipment. In this paper, the fault severity of the rotor bar has been derived in terms of the resistance change which is calculated from the equivalent circuit model. Results show that the fault of the rotor can be easily detected and the measured value of the resistance change is verified by the detected fault from on-site tests using MCSA for the induction motors in an iron foundry.

• BMB Reports
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• 제39권2호
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• pp.178-182
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• 2006

Four strains of Acidithiobacillus ferrooxidans with different iron oxidation capacity were isolated from different mine drainage stations. The 16S rRNA gene of these strains were cloned and sequenced. Based on our sequences analysis on the four strain and the data on the other strains deposited in Genbank, all A. ferrooxidans may be classified into three phylogenetic groups. The analysis data showed that nucleotide variables (signature sites) were detected in 21 positions, and most of them were found in the first 800bp from 5' terminal except position 970 and 1375. Interestingly, the first 13 signature sites were located in two main regions:the first region (position 175-234) located in V2 while the second region (position 390-439) were detected in constant region between V2 and V3. Furthermore, the secondary structure and minimal free energy were determined in two regions among strains of three groups. These results may be useful in characterizing the microevolutionary mechanisms of species formation and monitoring in biohydrometallurgical application.

• 한국자기공명학회논문지
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• 제18권1호
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• pp.10-14
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• 2014

Hsp90 is a good drug target molecule that is involved in regulating various signaling pathway in normal cell and the role of Hsp90 is highly emphasized especially in cancer cells. Thus, much efforts for discovery and development of Hsp90 inhibitor have been continued and a few Hsp90 inhibitors targeting the N-terminal ATP binding site are being tested in the clinical trials. There are no metabolic signature molecules that can be used to evaluate the effect of Hsp90 inhibition. We previously found a potential C-domain binder named PPC1 that is a synthetic small molecule. Here we report the metabolomics study to find signature metabolites upon treatment of PPC1 compound in lung cancer cell line, A549 and discuss the potentiality of metabolomic approach for evaluation of hit compounds.

• Journal of electromagnetic engineering and science
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• 제14권2호
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• pp.79-81
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• 2014

In B-scan data measured by a pulse-type monostatic borehole radar, target signatures are seriously obscured by two clutters that differ in orientation and intensity. The primary clutter appears as a nearly constant time delay, which is caused by internal ringing between antenna and transceiver in the radar system. The secondary clutter occurs as an oblique time delay due to the guided borehole wave along the logging cable of the radar antenna. This issue led us to perform adaptive filtering processing for orientation-based clutter removal. This letter describes adaptive filtering processing consisting of a combination of edge detection, data rotation, and eigenimage filtering. We show that the hyperbolic signatures of a dormant air-filled tunnel target can be more distinctly enhanced by applying the proposed approach to the B-scan data, which are measured in a well-suited test site for underground tunnel detection.

• Journal of Microbiology and Biotechnology
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• 제19권3호
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• pp.217-228
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• 2009

Mobile genetic segments, or transposons, are also referred to as jumping genes as they can shift from one position in the genome to another, thus inducing a chromosomal mutation. According to the target site-specificity of the transposon during a transposition event, the result is either the insertion of a gene of interest at a specific chromosomal site, or the creation of knockout mutants. The former situation includes the integration of conjugative transposons via site-specific recombination, several transposons preferring a target site of a conserved AT-rich sequence, and Tn7 being site-specifically inserted at attTn7, the downstream of the essential glmS gene. The latter situation is exploited for random mutagenesis in many prokaryotes, including IS (insertion sequence) elements, mariner, Mu, Tn3 derivatives (Tn4430 and Tn917), Tn5, modified Tn7, Tn10, Tn552, and Ty1, enabling a variety of genetic manipulations. Randomly inserted transposons have been previously employed for a variety of applications such as genetic footprinting, gene transcriptional and translational fusion, signature-tagged mutagenesis (STM), DNA or cDNA sequencing, transposon site hybridization (TraSH), and scanning linker mutagenesis (SLM). Therefore, transposon-mediated genetic engineering is a valuable discipline for the study of bacterial physiology and pathogenesis in living hosts.

• JSTS:Journal of Semiconductor Technology and Science
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• 제13권3호
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• pp.259-262
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• 2013

Multi-site testing is considered as a solution to reduce test costs. This paper presents a new channel sharing architecture that enables I/O pins to share automatic test equipment (ATE) channels using simple circuitry such as tri-state buffers, AND gates, and multiple-input signature registers (MISR). The main advantage of the proposed architecture is that it is implemented on probe cards and does not require any additional circuitry on a target device under test (DUT). In addition, the proposed architecture can perform DC parametric testing of the DUT such as leakage testing, even if the different DUTs share the same ATE channels. The simulation results show that the proposed architecture is very efficient and is applicable to both wafer testing and package testing.

• 국제초고층학회논문집
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• 제6권4호
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• pp.315-322
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• 2017

A modern and highly-sustainable addition to the skyline of Seoul, South Korea has been completed; the Federation of Korean Industries Headquarters (FKI). The signature saw-toothed exterior wall of the 245-meter tall tower and the contrasting smooth nature of the pipe-shell structured podium "egg" gives this project and site a unique identity in the city.