• Journal of the Korea Institute of Information Security & Cryptology
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• v.15 no.1
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• pp.57-66
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• 2005

SHACAL-2 is a 256-bit block cipher with various key sizes based on the hash function SHA-2. Recently, it was recommended as one of the NESSIE selections. This paper presents differential-linear type attacks on SHACAL-2 with 512-bit keys up to 32 out of its 64 rounds. Our 32-round attack on the 512-bit keys variants is the best efficient attack on this cipher in published literatures.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.11 no.6
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• pp.127-134
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• 2001

At PKC\`98, SangUk Shin et al. proposed a new hash function based on advantages of SHA-1, RIPEMD-160, and HAVAL. They claimed that the Boolean functions of the hash function have good properties including the SAC(Strict Avalanche Criterion). In this paper, we first show that some of Boolean functions which are used in Shin\`s hash function does not satisfy the SAC, and then argue that satisfying the SAC may not be a good property of Boolean functions, when it is used for constructing compress functions of a hash function.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.5
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• pp.87-93
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• 2002

SHACAL is based on the hash standard SHA-1 used in encryption mode, as a submission to NESSIE. SHACAL uses the XOR, modular addition operation and the functions of bit-by-bit manner. These operations and functions make the differential cryptanalysis difficult, i.e, we hardly find a long differential with high probability. But, we can find short differentials with high probability. Using this fact, we discuss the security of SHACAL against the amplified boomerang attack. We find a 36-step boomerang-distinguisher and present attacks on reduced-round SHACAL with various key sizes. We can attack 39-step with 256-bit key, and 47-step with 512-bit key.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.239-246
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• 2014

Purpose: This study was performed to investigate the effect of induced ametropia on static posture for body balance. Methods: Twenty subjects (10 males, 10 females) of average age $23.4{pm}2.70$ years were participated and ametropia(binocular myopia; BM, simple myopic anisometropia; SMA, binocular hyperopia; BH, and simple hyperopic anisometropia; SHA) were induced with ${pm}0.50D$, ${\pm}1.00D$, ${\pm}1.50D$, ${\pm}2.00D$, ${\pm}3.00D$, ${\pm}4.00D$, ${\pm}5.00D$, respectively. General stability (ST), weight distribution index (WDI), and fall risk index (FI) were measured using TETRAX the biofeedback systems. Each index of the body balance was evaluated for 32 seconds in each ametropic condition and those value was compared with the value in fully corrected condition. Results: The ST showed significant increase from +0.50 D under condition of BM, from +1.00 D under condition of SMA, from -1.00 D under condition of BH, and from -1.50 D under condition of SHA compared with under condition of fully corrected condition, respectively. The FI showed significant increases from +4.00 D under condition of BM, from -1.00 D under condition of BH, and from -1.50 D under condition of SHA. The WDI show no change in all ametropia condition. Conclusions: Whatever ametropia is, uncorrected refractive error could reduce the general stability of body balance and increase the falling risk.

• The Journal of Korean Obstetrics and Gynecology
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• v.30 no.3
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• pp.1-19
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• 2017

Objectives: The object of this study is to observe the possible ameliorating effects of Nokyongdaebo-tang (NYDBT) on the experimental subacute hemorrhagic anemia (SHA) in rats. Methods: In the present study, SHA in rats was induced by exsanguinations from orbital plexus, and ameliorating effects of NYDBT was observed based on the changes of body and hematopoietic organ (spleen, liver and femur) weights, red blood cell (RBC) related hematological values, smear cytology, histopathological changes and immunohistochemistrical analysis of hematopoietic stem cells in the femur bone marrow, liver and spleen. In addition, the gastrointestinal motility and the surface mucosa thicknesses of remnant fecal pellets in the colon lumen, mucosa thicknesses and the mucous producing cell numbers in the colonic mucosa were analyzed to observe the digestive disorders, especially on the constipation, the major discomfort problems in iron supplement. Results: SHA related abnormal anemic signs were markedly and dose-dependently inhibited by oral administration of NYDBT 500, 250 and 125 mg/kg in a condition of this experiment. In addition, no meaningful changes on the gastrointestinal motilities and mucous component on the colon and remnant feces were noticed in all three different dosages of NYDBT treated rats as compared with intact vehicle and SHA control rats in this study. Conclusions: It, therefore, is expected that NYDBT will be promising as a novel alternative hematopoietic and therapeutic agent for anemia.

• Journal of the Korean Chemical Society
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• v.41 no.4
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• pp.214-218
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• 1997

• Journal of the Korean Society of Food Science and Nutrition
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• v.5 no.1
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• pp.53-59
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• 1976

Around 2nd century B. C. two varieties of apple, i. e. 'Nay' and 'Imgum' were already grown in China. It can be suspected that 'Nay' came from the West because of its popular word 'Pyn Por' and 'Imgum' was originated from North East Asia because of its word 'Lii Kiem'. After this time 'Imgum' was called as its popular name 'Sha Guoo' in about 15 th century. In 17th century a new variety of 'Nay' was named as 'Pyng Guoo' and this name was replaced with 'Nay' when the variety was widely supplied. In 19th century a better variety of 'Nay' was developed in the West and it was introduced into China in 20th century which was called 'Western Pyng Guoo'. As a result there were two kinds of 'Pyng Guoo', i. e. 'Chinese Pyng Guoo' and 'Western Pyng Guoo'. However, the 'Western Pyng Guoo' was more supplied and it was said 'Pyng Guoo' which was written as 'Pyng Guoo(?果)' or 'Pyng Guoo (平果)'. At present time apples were classified into 'Sha Guoo' and 'Pyng Guoo'. The old 'Nay' is now called 'Bin Tzyy' which is hardly found. From this study it is suspected that the history of Chinese apples were affected much on our introduction history and its naming.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.6
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• pp.19-25
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• 2017

This paper deals with integer factorization of two prime p,q of SHA-256 secure hash value n for Bit coin mining. This paper proposes an algorithm that greatly reduces the execution time of Pollard's rho integer factorization algorithm. Rho(${\rho}$) algorithm computes $x_i=x^2_{i-1}+1(mod\;n)$ and $y_i=[(y^2_{i-1}+1)^2+1](mod\;n)$ for intial values $(x_0,y_0)=(2,2)$ to find the factor 1 < $gcd({\mid}x_i-y_i{\mid},n)$ < n. It however fails to factorize some particular composite numbers. The algorithm proposed in this paper applies multiple initial values $(x_0,y_0)=(2^k,2^k)$ and ($2^k,2$), $2{\leq}k{\leq}10$ to the existing Pollard's Rho algorithm. As a results, the proposed algorithm achieves both the factorization of all the composite numbers and the reduction of the execution time of Pollard's Rho by 67.94%.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.2
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• pp.65-73
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• 2008

Security layer of the Cdma2000 1x EV-DO is currently completing standard (C.S0024-A v2.0). Accordingly, a hardware security devices, that allows to implementation requirement of the security layer described in standard document, is required to apply security function about data transferred between AT and AN of then Cdma2000 1x EV-DO environment. This paper represents design of hardware device providing EV-DO security with simulation of the security layer protocol via the FPGA platform. The SHA-1 hash algorithm for certification and service of packet data, and the AES, SEED, ARIA algorithms for data encryption are equip in this device. And paper represents implementation of hardware that applies optionally certification and encryption function after executing key-switch using key-switching algorithm.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.7
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• pp.122-130
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• 2013

This work proposes a 12b 100MS/s 45nm CMOS four-step pipeline ADC for high-speed digital communication systems requiring high resolution, low power, and small size. The input SHA employs a gate-bootstrapping circuit to sample wide-band input signals with an accuracy of 12 bits or more. The input SHA and MDACs adopt two-stage op-amps with a gain-boosting technique to achieve the required DC gain and high signal swing range. In addition, cascode and Miller frequency-compensation techniques are selectively used for wide bandwidth and stable signal settling. The cascode current mirror minimizes current mismatch by channel length modulation and supply variation. The finger width of current mirrors and amplifiers is laid out in the same size to reduce device mismatch. The proposed supply- and temperature-insensitive current and voltage references are implemented on chip with optional off-chip reference voltages for various system applications. The prototype ADC in a 45nm CMOS demonstrates the measured DNL and INL within 0.88LSB and 1.46LSB, respectively. The ADC shows a maximum SNDR of 61.0dB and a maximum SFDR of 74.9dB at 100MS/s, respectively. The ADC with an active die area of $0.43mm^2$ consumes 29.8mW at 100MS/s and a 1.1V supply.