• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2010년도 추계학술발표대회
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• pp.1183-1185
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• 2010

2005년 중국의 Wang 등이 SHA-1의 충돌쌍 공격에 대한 취약성을 발표한 이후 미국의 NIST(National Institute of Standards and Technologies)에서는 새로운 표준 해쉬 함수에 대한 필요성을 제기하였으며, SHA-3로 사용될 새로운 해쉬 함수를 공모하게 되었다. 전세계에서 64개의 후보들이 제안되었으며, 1라운드가 끝난 2010년 현재 14개의 후보들에 대한 2 라운드 심사가 진행중이다. 본 논문에서는 ASIC(Application Specified Intergrated Circuit) 설계 과정에서 설계 대상의 전력 소모량을 추정하는 과정을 소개하고, 이를 이용해 SHA-3 후보들의 H/W 구현들에 대해서 전력 소모량을 추정하여 결과를 제시한다.

• Journal of Microbiology and Biotechnology
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• 제23권2호
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• pp.149-155
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• 2013

Heterologous expression of a putative $K^+/H^+$ antiporter of Streptomyces coelicolor A3(2) (designated as sha4) in E. coli and Streptomyces hygroscopicus JCM4427 showed enhanced tolerance to $K^+$ stress, acidic-pH shock, and/or geldanamycin production under $K^+$ stress. In a series of $K^+$ extrusion experiments with sha4-carrying E. coli deficient in the $K^+/H^+$ antiporter, a restoration of impaired $K^+$ extrusion activity was observed. Based on this, it was concluded that sha4 was a true $K^+/H^+$ antiporter. In different sets of experiments, the sha4-carrying E. coli showed significantly improved tolerances to $K^+$ stresses and acidic-pH shock, whereas sha4-carrying S. hygroscopicus showed an improvement in $K^+$ stress tolerance only. The sha4-carrying S. hygroscopicus showed much higher geldanamycin productivity than the control under $K^+$ stress condition. In another set of experiments with a production medium, the secretion of geldanamycin was also significantly enhanced by the expression of sha4.

• 대한전자공학회논문지SD
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• 제47권4호
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• pp.41-49
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• 2010

본 논문은 다중 언폴딩 기법을 이용한 고속 SHA-1 해쉬 알고리즘 구현 방법을 제시하였다. 제안된 SHA-1 해쉬 구조는 알고리즘의 반복적인 단계 연산을 언폴딩한 후 연산의 순서를 재 배열하고, 임계경로에 포함된 연산의 일부를 이전 단계에서 선행연산하여 임계경로의 길이를 줄였다. 제안된 SHA-1 해쉬 구조는 최대 118 MHz의 동작주파수에서 5.9 Gbps 처리량을 나타낸다. 이는 기존의 SHA-1 보다 전송량이 26% 증가하였고, 회로 크기가 32% 감소하는 결과를 얻었다. 또한 이 논문에서는 여러 개의 SHA-1 모듈을 시스템 레벨에서 병렬로 연결하여 여러 개의 SHA-1을 다중 처리하여 고속화를 할 수 있는 모델을 제안했다. 이 모델은 하나의 SHA-1을 사용하는 것보다 빠르게 데이터를 처리할 수 있고 입력되는 데이터의 최소한의 지연으로 처리 가능하다. 제안된 모델은 입력되는 데이터가 지연 없이 처리 되도록 하기 위해 필요로 하는 SHA-1의 FPGA 수를 구할 수도 있다. 고속화된 SHA-1은 압축된 메시지에 유용하게 사용될 수 있고 모바일 통신이나 인터넷 서비스 등의 강한 보안에 널리 이용가능하다.

• 한국전자통신학회논문지
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• 제7권2호
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• pp.295-301
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• 2012

본 논문에서는 고속 ADC의 앞단에서 사용하기 위한 1 $V_{pp}$의 입력 신호 범위에서 12 Bit의 해상도를 갖고 100 MS/s의 샘플링 속도에서 동작하는 SHA를 설계하였다. 제안된 시스템은 입력 주파수가 5 MHz, 샘플링 주파수 100 MHz 일 때 SFDR(Spurious Free Dynamic Range)가 약 66.3 dB로 해상도가 떨어졌으나 feedthrough를 제거한 회로는 SFDR이 약 73 dB로 12 bit 해상도를 갖는다.

• Journal of Microbiology and Biotechnology
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• 제21권9호
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• pp.979-987
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• 2011

Culture pH change has some important roles in signal transduction and secondary metabolism. We have already reported that acidic pH shock enhanced actinorhodin production in Streptomyces coelicolor. Among many potential governing factors on pH variation, the putative $Na^+/H^+$ antiporter (sha) genes in S. coelicolor have been investigated in this study to elucidate the association of the sha on pH variation and secondary metabolism. Through the transcriptional analysis and overexpression experiments on 8 sha genes, we observed that most of the sha expressions were promoted by pH shock, and in the opposite way the pH changes and actinorhodin production were enhanced by the overexpression of each sha. We also confirmed that sha8 especially has a main role in maintaining cell viability and pH homeostasis through $Na^+$ extrusion, in salt effect experiment under the alkaline medium condition by deleting sha8. Moreover, this gene was observed to have a function of pH recovery after pH variation such as the pH shock, being able to cause the sporulation. However, actinorhodin production was not induced by the only pH recovery. The sha8 gene could confer on the host cell the ability to recover pH to the neutral level after pH variation like a pH drop. Sporulation was closely associated with this pH recovery caused by the action of sha8, whereas actinorhodin production was not due to such pH variation patterns alone.

• 한국전문물리치료학회지
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• 제23권3호
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• pp.57-67
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• 2016

Background: Many previous studies recommended the side-lying hip abduction (SHA) exercise for targeting the gluteus medius (Gmed) and gluteus maximus (Gmax) muscle activity while the decreasing tensor fasciae latae (TFL) activation. Mischoice of hip position and angle in SHA may increase the risk of lower extremity injuries and undesirable muscle activation. However, information is limited on the effect of composite hip flexion angles and hip rotation on the gluteal muscle activity during SHA. Objects: This study aimed to compare muscle activity (Gmed, TFL, and Gmax) and activity ratios (Gmed/TFL, Gmax/TFL, and Gmed/Gmax) using surface electromyography (EMG) during SHA exercise at three different hip flexion angles either with or without internal rotation (IR) in subjects with Gmed weakness. We hypothesized that applying hip flexion and IR during SHA would increase gluteal muscle activity and decrease TFL activity. Methods: Muscle activity and activity ratios in 20 volunteers with Gmed weakness during 6 different SHA were investigated with surface EMG. One-way repeated-measures analysis of variance was used to determine the statistical significance. Results: Significant differences were found among the six different exercises for Gmed ($F_{2,41}=11.817$, p<.001) and Gmax ($F_{3,52}=5.513$, p=.003) muscle activity, and Gmed/TFL ($F_{3,54}=8.735$, p<.001) and Gmax/TFL ($F_{2,37}=4.019$, p=.028) activity ratios. Conclusion: Applying hip flexion is an effective method for increasing gluteal activity, and it elicits great Gmed/TFL and Gmax/TFL activity ratios during SHA in subjects with Gmed weakness.

• Journal of Acupuncture Research
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• 제21권3호
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• pp.145-167
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• 2004

Objective : Neuropathic pain can be caused by a partial peripheral nerve injury. This kind of pain is usually accompanied by spontaneous burning pain, allodynia and hyperalgesia. It is not clear that scolopendrid aqua-acupuncture can control neuropathic pain effectively. The purpose of this study is to examine if scolopendrid aqua-acupuncture may be effective to the neuropathic pain (mechanical allodynia, cold allodynia) in a rat model of neuropathic pain. Methods : To produce the model of neuropathic pain, under isoflurane 2.5% anesthesia, tibial nerve and sural nerve was resected. After the neuropathic surgery, the author examined if the animals exhibited the behavioral signs of allodynia. The allodynia was assessed by stimulating the medial malleolus with von Frey filament and acetone. Three weeks after the neuropathic surgery, scolopendrid aqua-acupuncture was injected at Hwando(GB30) one time a day for one week. After that the author examined the withdrawl response of neuropathic rats' legs by von Frey filament and acetone stimulation. And also the author examined c-fos in the midbrain central gray of neuropathic rats and the change of WBC count in the blood of neuropathic rats. Results & Conclusion : 1. The scolopendrid aqua-acupuncture injected at Hwando(GB30) decreased the withdrawl response of mechanical allodynia in SHA-1, SHA-2 and SAH-3 group as compared with control group. 2. The scolopendrid aqua-acupuncture injected at Hwando(GB30) decreased the withdrawl response of chemical allodynia(cold allodynia) in SHA-1, SHA-2 and SAH-3 group as compared with control group. 3. The scolopendrid aqua-acupuncture injected at Hwando(GB30) showed the significant difference between sham group and control group(p=0.01), sham and SHA-3 group(p=0.026), control group and SHA-1 group(p=0.01), control group and SHA-2 group(p=0.024) in the c-fos expression. 4. The scolopendrid aqua-acupuncture injected at Hwando(GB30) showed the significant difference between sham group and SHA-3 group(p=0.010), control group and SHA-3 group(p=0.006) in the WBC count.

• Journal of Information Processing Systems
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• 제12권2호
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• pp.310-321
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• 2016

TCS_SHA-3 is a family of four cryptographic hash functions that are covered by a United States patent (US 2009/0262925). The digest sizes are 224, 256, 384 and 512 bits. The hash functions use bijective functions in place of the standard compression functions. In this paper we describe first and second preimage attacks on the full hash functions. The second preimage attack requires negligible time and the first preimage attack requires $O(2^{36})$ time. In addition to these attacks, we also present a negligible time second preimage attack on a strengthened variant of the TCS_SHA-3. All the attacks have negligible memory requirements. To the best of our knowledge, there is no prior cryptanalysis of any member of the TCS_SHA-3 family in the literature.

• 정보보호학회논문지
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• 제20권2호
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• pp.3-14
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• 2010

본 논문에서는 ARIRANG, HAS-160, PKC98-Hash의 단계-축소 버전에 대한 역상공격 결과를 소개한다. 이 공격에는 Aoki와 Sasaki가 SHA-0와 SHA-1의 단계-축소 버전을 공격하는데 이용한 chunk 검색 방법이 응용되었다. 본 논문에서 소개하는 공격 알고리즘들은 각각 ARIRANG, HAS-160, PKC98-Hash의 35단계, 65단계, 80단계에 대하여 전수조사보다 빠른시간내에 역상을 찾는다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2021년도 춘계학술대회
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• pp.63-65
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• 2021

보안 SoC (system-on-chip)를 이용한 타원곡선 디지털 서명 알고리듬 (elliptic curve digital signature algorithm; EC-DSA)의 H/W-S/W 통합 구현에 대해 기술한다. 보안 SoC는 Cortex-A53 APU를 CPU로 사용하며, 하드웨어 IP로 설계된 고성능 타원곡선 암호 (high-performance ellipitc curve cryptography; HP-ECC) 코어와 SHA3 (secure hash algorithm 3) 해시 함수 코어가 AXI4-Lite 버스 프로토콜로 연결된다. 고성능 ECC 코어는 12가지의 타원곡선을 지원하며, SHA3 코어는 4가지의 해시 함수를 지원한다. 보안 SoC를 Zynq UltraScale+ MPSoC 디바이스에 구현하여 EC-DSA에 의해 생성된 서명의 유효성을 검증하였다.