• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.49 no.3
• /
• pp.74-80
• /
• 2012

Recently at SCIS2011, Nakatsu et. al. proposed multi-round Correlation Power Analysis(CPA) on Hardware Advanced Encryption Standard(AES) to improve the performance of CPA with limited number of traces. In this paper, we propose, Multi-Round CPA to retrieve master key using CPA of 1round and 2round on Hardware DES. From the simulation result for the proposed attack method, we could extract 56-bit master key using the 300 power traces of Hardware DES in DPA contes. And it was proved that we can search more master key using multi-round CPA than using single round CPA in limited environments.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.53 no.6
• /
• pp.146-151
• /
• 2016

In this paper, we present a method for estimating the ratio of CPA distance to velocity of underwater target using target bearing information in CPA situation. This ratio can be estimated by previous research which is Envelope CPA using proximity sensor but it has low performance if the target is close to receiver sensor or bigger interference caused by multi-path effects. Therefore we propose a Bearing CPA technique using a target bearing information as a way to overcome.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.21 no.7
• /
• pp.1276-1284
• /
• 2017

Lightweight Encryption Algorithm (LEA) that was standardized as a lightweight block cipher was implemented with 8-bit data path, and the vulnerability of LEA encryption processor to correlation power analysis (CPA) attack was analyzed. The CPA used in this paper detects correct round keys by analyzing correlation coefficient between the Hamming distance of the computed data by applying hypothesized keys and the power dissipated in LEA crypto-processor. As a result of CPA attack, correct round keys were detected, which have maximum correlation coefficients of 0.6937, 0.5507, and this experimental result shows that block cipher LEA is vulnerable to power analysis attacks. A masking method based on TRNG was proposed as a countermeasure to CPA attack. By applying masking method that adds random values obtained from TRNG to the intermediate data of encryption, incorrect round keys having maximum correlation coefficients of 0.1293, 0.1190 were analyzed. It means that the proposed masking method is an effective countermeasure to CPA attack.

• Journal of the Korea Society of Computer and Information
• /
• v.27 no.1
• /
• pp.43-50
• /
• 2022

Correlation Power Analysis(CPA) is a sub-channel attack method that measures the detailed power consumption of attack target equipment equipped with cryptographic algorithms and guesses the secret key used in cryptographic algorithms with more than 90% probability. Since CPA performs analysis based on statistics, a large amount of data is necessarily required. Therefore, the CPA must measure power consumption for at least about 15 minutes for each attack. In this paper proposes a method of using a Convolutional Neural Network(CNN) capable of accumulating input data and predicting results to solve the data collection problem of CPA. By collecting and learning the power consumption of the target equipment in advance, entering any power consumption can immediately estimate the secret key, improving the computational speed and 96.7% of the secret key estimation accuracy.

• YAKHAK HOEJI
• /
• v.30 no.2
• /
• pp.87-95
• /
• 1986

Inclusion complexation of $\alpha$-cyclodextrin($\alpha$-CD), $\beta$-cyclodextrin($\beta$-CD) and tri-O-methyl-$\beta$-cyclodextrin(tri-O-methyl-$\beta$-CD) with chlorpamide(CPA) in aqueous solution and in the solid state were studied by the solubility method, spectroscopy (UV, IR), differential scanning calorimetry (DSC) and powder X-ray diffractometry, and all their molar ratios were found to be 1:1. The solid complexes of CPA with three kinds of cyclodextrins were prepared by a freezedrying method, and their dissolution behaviors were examined. As a result, the release of CPA from the inclusion complexes was significantly improved. The intrinsic dissolution rate of CPA in cyclodextrin inclusion complexes was about 51 times ($\alpha$-CD inclusion complex) and 12 tmies ($\beta$-CD inclusion complex) larger than that of intact CPA.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.24 no.5
• /
• pp.1013-1022
• /
• 2014

Correlation Power Analysis (CPA) is a type of Side-Channel Analysis (SCA) that extracts the secret key using the correlation coefficient both side-channel information leakage by cryptography device and intermediate value of algorithms. Attack performance of the CPA is affected by noise and temporal synchronization of power consumption leaked. In the recent years, various researches about the signal processing have been presented to improve the performance of power analysis. Among these signal processing techniques, compression techniques of the signal based on Principal Component Analysis (PCA) has been presented. Selection of the principal components is an important issue in signal compression based on PCA. Because selection of the principal component will affect the performance of the analysis. In this paper, we present a method of selecting the principal component by using the correlation of the principal components and the power consumption is high and a CPA technique based on the principal component that utilizes the feature that the principal component has different. Also, we prove the performance of our method by carrying out the experiment.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.44 no.6
• /
• pp.665-670
• /
• 2011

The rotifer Brachionus plicatilis is one of the most important food organisms in aquaculture. The resting eggs produced by mictic female rotifers are easily stored and hatched, making them useful as the starter for the mass culture of rotifers in marine larval culture. This study examined the optimum preservation method for resting eggs to ensure a high hatching rate. To produce resting eggs, the marine rotifer B. plicatilis was cultured with Nannochloris oculata (KMMCC 16). The resting eggs were harvested and cryopreserved using 5% and 10% methanol (MeOH), dimethylsulfoxide (DMSO), and glycerol as cryoprotectant agents (CPAs). The cryopreservation comprised slow or rapid freezing and the resting eggs were stored for one month in liquid nitrogen ($-196^{\circ}C$). The resting eggs were also dried at different temperatures (30, 40, and $50^{\circ}C$) and for different times (1, 2, and 3 h). In general, the hatching rates of the resting eggs preserved with CPA were higher than those without CPA and the slow freezing method was better than the rapid freezing method. However, the optimum CPA concentration for the hatching rate of the resting eggs varied with the freezing method and kind of CPA, and the CPA also affected the viability of the resting eggs. Dried resting eggs had a high, rapid hatching rate over 80%. The moisture content of the resting eggs cryopreserved in liquid nitrogen affected the hatching rate. Drying at $30^{\circ}C$ for 1 hour resulted in a high hatching rate of the resting eggs. In conclusion, drying at $30^{\circ}C$ for 1 hour and preservation in liquid nitrogen with the slow freezing method, without CPA, is recommended for a high hatching rate (ca. 95%) of rotifer resting eggs.

• Clean Technology
• /
• v.19 no.1
• /
• pp.59-64
• /
• 2013

Pt/carbon Electrode catalysts for PEMFC were synthesized using colloidal method. PSA (platinum sulfite acid) was used as a Pt precursor and CPA (chloroplatinic acid) was also used to replace relatively expensive PSA. Electrode catalysts prepared using PSA showed Pt particle size less than 3.5 nm and Pt yield higher than 90% in 10~40 wt% Pt loading. Electrode catalysts prepared using CPA also showed Pt particle size less than 4.4 nm and Pt yield higher than 80% in 10~40 wt% Pt loading. The MEA (membrane electrode assembly) using 20 wt% Pt/VXC72 showed equivalent I-V curve comparing with commercial electrode catalyst in single cell test.

• Proceedings of the KIEE Conference
• /
• 2002.07b
• /
• pp.571-576
• /
• 2002

Electromagnetic analysis has been made for the design of 3 MJ Compulsator (Compensated Pulsed Alternator, CPA) that will be used as the power supply system of the electrothermal-chemical launcher system. using finite element method with ANSYS/Emag. From the analysis results, it was possible to decide the excitation MMF and the rotor/stator size to obtain the desired output current. And using electromagnetic forces from the analysis results. the stresses on the components of 3 MJ CPA could be analyzed. The detailed design based on the analysis results has been made and the fabrication of 3 MJ CPA is in progress. Before assembling components into 3 MJ CPA. an experiment is being made to check the correspondence between analysis results and measurements.

• Korean Journal of Construction Engineering and Management
• /
• v.5 no.6 s.22
• /
• pp.129-137
• /
• 2004

When we consider the present state of construction delay claim analysis, the delay analysis methods generally used from the abroad construction industries are not applied to our industry. By reviewing the existing methods of delay analysis, this study investigated the important concepts and characteristics of the delay analysis methods. Selection of the delay analysis methods could be decided among 1)As-planned versus as-built comparison method,2)What-if method,3)But-for method.4)CPA method, and 5)DAMUDS method. In order to make clear the characteristics and mechanisms of the analysis methods, this study performed a case study.