• Title/Summary/Keyword: masking technique

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Suggestion of CPA Attack and Countermeasure for Super-Light Block Cryptographic CHAM (초경량 블록 암호 CHAM에 대한 CPA 공격과 대응기법 제안)

  • Kim, Hyun-Jun;Kim, Kyung-Ho;Kwon, Hyeok-Dong;Seo, Hwa-Jeong
    • KIPS Transactions on Computer and Communication Systems
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    • v.9 no.5
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    • pp.107-112
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    • 2020
  • Ultra-lightweight password CHAM is an algorithm with efficient addition, rotation and XOR operations on resource constrained devices. CHAM shows high computational performance, especially on IoT platforms. However, lightweight block encryption algorithms used on the Internet of Things may be vulnerable to side channel analysis. In this paper, we demonstrate the vulnerability to side channel attack by attempting a first power analysis attack against CHAM. In addition, a safe algorithm was proposed and implemented by applying a masking technique to safely defend the attack. This implementation implements an efficient and secure CHAM block cipher using the instruction set of an 8-bit AVR processor.

Maskless Pattern Fabrication on Si (100) Surface by Using Nano Indenter with KOH Wet Etching (나노인덴터와 KOH 습식 식각 기술을 병용한 Si(100) 표면의 마스크리스 패턴 제작 기술)

  • 윤성원;신용래;강충길
    • Transactions of Materials Processing
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    • v.12 no.7
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    • pp.640-646
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    • 2003
  • The nanoprobe based on lithography, mainly represented by SPM based technologies, has been recognized as potential application to fabricate the surface nanostructures because of its operational versatility and simplicity. The objective of the work is to suggest new mastless pattern fabrication technique using the combination of machining by nanoindenter and KOH wet etching. The scratch option of the nanoindenter is a very promising method for obtaining nanometer scale features on a large size specimen because it has a very wide working area and load range. Sample line patterns were machined on a silicon surface, which has a native oxide on it, by constant load scratch (CLS) of the Nanoindenter with a Berkovich diamond tip, and they were etched in KOH solutions to investigate chemical characteristics of the machined silicon surface. After the etching process, the convex structure was made because of masking effect of the affected layer generated by nano-scratch. On the basis of this fact, some line patterns with convex structures were fabricated. Achieved patterns can be used as a mold that will be used for mass production processes such as nanoimprint or PDMS molding process. All morphological data of scratch traces were scanned using atomic force microscope (AFM).

A Secure ARIA implementation resistant to Differential Power Attack using Random Masking Method (랜덤 마스킹 기법을 이용한 DPA 공격에 안전한 ARIA 구현)

  • Yoo Hyung-So;Kim Chang-Kyun;Park Il-Hwan;Moon Sang-Jae;Ha Jae-Cheol
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.16 no.2
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    • pp.129-139
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    • 2006
  • ARIA is a 128-bit block cipher, which became a Korean Standard in 2004. According to recent research this cipher is attacked by first order DPA attack In this paper, we explain a masking technique that is a countermeasure against first order DPA attack and apply it to the ARIA. And we implemented a masked ARIA for the 8 bit microprocessor based on AVR in software. By using this countermeasure, we verified that it is secure against first order DPA attack.

Development of Fast Dissolving Tablet Containing Herb Extract by Freeze-Drying Technique

  • Kim, Jae-Il;Choi, Hoo-Kyun
    • Journal of Pharmaceutical Investigation
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    • v.40 no.3
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    • pp.161-166
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    • 2010
  • A fast dissolving tablet was developed using the freeze-drying technique. Hyeonggaeyeongyotang was selected as a model oriental medicine. Formulation and processing parameters were studied to obtain freeze-dried tablet with high drug loading, good palatability, and fast disintegration time. $Kollidon^{(R)}$ CLM served as both matrix former and taste masking agent. Ethanol used as co-solvent, decreased the disintegration time of tablet. Aspartame was employed to impart better taste. Drying condition was found to have a major effect in the morphology of the tablets. Freeze-drying process was optimized to decrease the processing time and improve the appearance of the tablets.

A Study on Watermark Technique for Copyright Protection of Digital Images (디지털 영상물의 저작권 보호를 위한 워터마크 기술에 관한 연구)

  • Hong, Min-Suk;Park, Kang-Seo;Chung, Tae-Yun;Shin, Joon-In;Park, Sang-Hui
    • Proceedings of the KIEE Conference
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    • 1998.11b
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    • pp.606-608
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    • 1998
  • Digital watermarking is the technique which embeds the invisible signal into multimedia data such as audio, video, images, for copyright protection, including owner identification and copy control information. In this paper, a new watermark detection algorithm by local masking cross covariance between watermarked signal and pseudo noise signal is proposed. The proposed algorithm enhances the detection probability for embedding information. Since reducing detection errors for the weak embedding signals, the algorithm improves the image quality and robusts against illegal attack to delete the embedding information and data compression applications such as JPEG and MPEGs.

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Application of Blind Deconvolution with Crest Factor for Recovery of Original Rolling Element Bearing Defect Signals (볼 베어링 결함신호 복원을 위한 파고율을 이용한 Blind Deconvolution의 응용)

  • Son, Jong-Duk;Yang, Bo-Suk;Tan, A.C.C.;Mathew, J.
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.585-590
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    • 2004
  • Many machine failures are not detected well in advance due to the masking of background noise and attenuation of the source signal through the transmission mediums. Advanced signal processing techniques using adaptive filters and higher order statistics have been attempted to extract the source signal from the measured data at the machine surface. In this paper, blind deconvolution using the eigenvector algorithm (EVA) technique is used to recover a damaged bearing signal using only the measured signal at the machine surface. A damaged bearing signal corrupted by noise with varying signal-to-noise (s/n) was used to determine the effectiveness of the technique in detecting an incipient signal and the optimum choice of filter length. The results show that the technique is effective in detecting the source signal with an s/n ratio as low as 0.21, but requires a relatively large filter length.

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The Hearing Ability of the Dusky spinefoot Siganus fuscescens(Houttuyn)to Audible Sound 2. The Auditory Critical Ratio (가청음에 의한 독가시치의 청각 능력 2. 청각 임계비)

  • Lee, Chang-Heon;Moon, Jong-Wook;Seo, Du-Ok
    • Journal of Fisheries and Marine Sciences Education
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    • v.12 no.2
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    • pp.191-198
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    • 2000
  • An experiment was carried out to obtain the fundamental data on the auditory thresholds of fishes for catching method using audible frequency sound, the auditory thresholds of dusky spinefoot Siganus fuscescens(Houttuyn) were measured in the presence of masking noise in the spectrum level range of 74 - 83dB re $1{\mu}Pa/{\sqrt{Hz}}$ by heartbeat conditioning technique using pure tones coupled with a delayed electric shock. The auditory critical ratios were about 23 - 34dB at measurement frequency range. The ratio increased almost linearly with increasing frequency from 200 to 500Hz. The noise spectrum level at the start of masking was about 61 - 73dB within the measurement frequency range. This suggests that hearing of dusky spinefoot is masked in the natural environment with the noise spectrum level above 70dB. The sound pressure level of which the signal sound of 100Hz is recognized by dusky spinefoot under the white noise of 70dB is above 98dB and the critical ratio of them is above 23dB.

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The Hearing Ability of Black Rockfish Sebastes inermis to Underwater Audible Sound 2. The Auditory Critical Ratio (수중 가청음에 의한 볼락의 청각 능력 2. 청각 임계비)

  • LEE Chang-Heon;SEO Du-Ok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.2
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    • pp.151-155
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    • 2001
  • In order to obtain the fundamental data on the auditory thresholds of fishes for marine ranching, the auditory thresholds of black rockfish Sebastes inermis were measured in the presence of masking noise in the spectrum level range of $73\~83$ dB (0 dB re $1{\mu}Pa/\sqrt{Hz}$) with a classical cardiac conditioning technique. Critical ratios were about $28\~34$ dB at $80\~300$ Hz and $47\~52$ dB at $500\~800$ Hz. The ratio increased almost linearly with increasing frequency to 500 Hz. The noise spectrum level at the start of masking was about 70 dB within the frequency range of $80\~800$ Hz excepting 65 dB at 300 Hz. It means that hearing of the black rockfish is masked in the natural environment with the noise spectrum level above 65 dB. The sound pressure level of $200\~300$ Hz recognized by black rockfish was above 96 dB under the ambient noise and the critical ratio of them was above 26 dB.

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Performance Improvement of a Variability-index CFAR Detector for Heterogeneous Environment (비균질 환경에 강인한 검출기를 위한 변동 지수 CFAR의 성능 향상)

  • Shin, Jong-Woo;Kim, Wan-Jin;Do, Dae-Won;Lee, Dong-Hun;Kim, Hyoung-Nam
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.49 no.3
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    • pp.37-46
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    • 2012
  • In RADAR and SONAR detection systems, noise environment can be classified into homogeneous and heterogeneous environment. Especially heterogeneous environments are modelled as target masking and clutter edge. Since the variability-index (VI) CFAR, a composed CFAR algorithm, dynamically selects one of the mean-level algorithms based on the VI and the MR (mean ratio) test, it is robust to various environments. However, the VI CFAR still suffers from lowered detection probabilities in heterogeneous environments. To overcome these problems, we propose an improved VI CFAR processor where TM (trimmed mean) CFAR and a sub-windowing technique are introduced to minimize the degradation of the detection probabilities appeared in heterogeneous environments. Computer simulation results show that the proposed method has the better performance in terms of detection probability and false alarm probability compared to the VI CFAR and single CFAR algorithms.

Iterative Pre-Whitening Projection Statistics for Improving Multi-Target Detection Performance in Non-Homogeneous Clutter (불균일 클러터 환경에서 다중 표적탐지 성능 향상을 위한 반복 백색화 투영 통계 기법)

  • Park, Hyuck;Kang, Jin-Whan;Kim, Sang-Hyo
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.49 no.4
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    • pp.120-128
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    • 2012
  • In this paper, we propose a modified iterative pre-whitening projection statistics (MIPPS) scheme for improving multi-target detection performance in non-homogeneous clutter environments. As a non-homogeneity detection (NHD) technique of space-time adaptive processing algorithm for airborne radar, the MIPPS scheme improves the average detection probability of weak target when multiple targets with different reflection signal intensities are located in close range. Numerical results show that the conventional NHD schemes suffers from the masking effect by strong targets and clutters and the proposed MIPPS scheme outperforms the conventional schemes with respect to the average detection probability of the weak target at low signal-to-clutter ratio.