• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.10
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• pp.23-30
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• 2008

Recently, a considerable number of studies have been conducted on pairing based cryptosystems. The efficiency of pairing based cryptosystems depends on finite fields, similar to existing public key cryptosystems. In general, pairing based ctyptosystems are defined over finite fields of chracteristic three, GF($3^m$), based on trinomials. A multiplication in GF($3^m$) is the most dominant operation. This paper proposes a new most significant digit(MSD)-first digit- serial multiplier. The proposed MSD-first digit-serial multiplier has the same area complexity compared to previous multipliers, since the modular reduction step is performed in parallel. And the critical path delay is reduced from 1MUL+(log ${\lceil}n{\rceil}$+1)ADD to 1MUL+(log ${\lceil}n+1{\rceil}$)ADD. Therefore, when the digit size is not $2^k$, the time delay is reduced by one addition.

• Journal of Elementary Mathematics Education in Korea
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• v.14 no.1
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• pp.123-134
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• 2010

Recently, mathematics education have been emphasized on developing students' mathematical thinking and problem solving abilities. Accordance with this emphasis, dramatical changes are needed in learning mathematics not merely let alone students solve real-made mathematics problems. The project learning to explore a counterweight activity will have an effects on positive mathematical attitude(to pose problem, to have curiosity) and mathematical thinking(power 10-digit representation, 2-digit number, two representation of 3-digit number, connect exponential number and log situation) which could develop understanding problems and critical thinking.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.11 no.2
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• pp.37-44
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• 2001

In this paper, an efficient architecture for the ECC multiplier in GF(2") is proposed. We give a design example for the irreducible trinomials $x_{193}\;+\;x_{15}\;+\;1$. In hardware implementations, it is often desirable to use the irreducible trinomial equations. A digit-serial multiplier with a digit size of 32 is proposed, which has more advantages than the 193bit serial LFSR architecture. The proposed multiplier is verified with a VHDL description using an elliptic curve addition. The elliptic curve used in this implementation is defined by Weierstrass equations. The measured results show that the proposed multiplier it 0.3 times smaller than the bit-serial LFSR multiplier.lier.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3865-3869
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• 2013

Background: Cigarette per day (CPD) use is a key smoking behaviour indicator. It reflects smoking intensity which is directly proportional to the occurrence of tobacco induced cancers. Self reported CPD assessment in surveys may suffer from digit bias and under reporting. Estimates from such surveys could influence the policy decision for tobacco control efforts. In this context, this study aimed at identifying underlying factors of digit bias and its implications for Global Adult Tobacco Surveillance. Materials or Methods: Daily manufactured cigarette users CPD frequencies from Global Adult Tobacco Survey (GATS) - India data were analyzed. Adapted Whipple Index was estimated to assess digit bias and data quality of reported CPD frequency. Digit bias was quantified by considering reporting of '0' or '5' as the terminal digits in the CPD frequency. The factors influencing it were identified by bivariate and logistic regression analysis. Results: The mean and mode of CPD frequency was 6.7 and 10 respectively. Around 14.5%, 15.1% and 15.2% of daily smokers had reported their CPD frequency as 2, 5 and 10 respectively. Modified Whipple index was estimated to be 226.3 indicating poor data quality. Digit bias was observed in 38% of the daily smokers. Heavy smoking, urban residence, North, South, North- East region of India, less than primary, secondary or higher educated and fourth asset index quintile group were significantly associated with digit bias. Discussion: The present study highlighted poor quality of CPD frequency data in the GATS-India survey and need for its improvement. Modeling of digit preference and smoothing of the CPD frequency data is required to improve quality of data. Marketing of 10 cigarette sticks per pack may influence CPD frequency reporting, but this needs further examination. Exploring alternative methods to reduce digit bias in cross sectional surveys should be given priority.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.5
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• pp.875-881
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• 2007

This study explores the attention effects of PPL(product placement) in multimedia contents. PPL has been attracted attention in multimedia as well as marketing communication field as a beneficiary model. For the research, multimedia screen is divided into 9 sections and the serial 9 digit($1{\sim}9$) is assigned to the each part of the screen. The visual exposure forms of each 9 digit are composed by 2-dimension(2D) and 3-dimension(3D). And the visual exposure patterns of each 9 digit are consisted of stopping and moving image. As a result, the 5th quartering has been proved the most attracted attention regardless of all exposure forms including 2D/3D and slopping/moving image. This means center of the multimedia screen is the best place for PPL. Especially in one digit moving screen the attention of the digit has reached the climax. This suggests moving PPL is able to get more attention than stopping. These results provide the most effective PPL position in the screen of the multimedia and PPL's visual exposure forms for maximizing multimedia user's attention. Finally, these findings can be a guideline fer message arrangements of the multimedia screen.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.499-503
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• 2000

The use of Multiple-Valued FFT(Fast fourier Transform) is extended from binary to multiple-valued logic(MVL) circuits. A multiple-valued FFT circuit can be implemented using current-mode CMOS techniques, reducing the transitor, wires count between devices to half compared to that of a binary implementation. For adder processing in FFT, We give the number representation using such redundant digit sets are called redundant positive-digit number representation and a Redundant set uses the carry-propagation-free addition method. As the designed Multiple-valued FFT internally using PD(positive digit) adder with the digit set 0,1,2,3 has attractive features on speed, regularity of the structure and reduced complexities of active elements and interconnections. for the mutiplier processing, we give Multiple-valued LUT(Look up table)to facilitate simple mathmatical operations on the stored digits. Finally, Multiple-valued 8point FFT operation is used as an example in this paper to illuatrates how a multiple-valued FFT can be beneficial.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.1
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• pp.157-165
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• 2013

In this paper, efficient digit-serial VLSI architecture for 1D (9,7) lifting-based discrete wavelet transform (DWT) filter has been proposed. The proposed architecture computes the DWT in digit basis, so that the required hardware is reduced. Also, the multiplication is replaced with the shift and add operation to minimize the hardware requirement. Bit allocation for input, output, and the internal data has been determined by analyzing the PSNR. We have carefully designed the data feedback latency not to degrade the performance in the recursive folded scheduling. The proposed digit-serial architecture requires small amount of hardware but achieve 100% of hardware utilization, so we try to optimize the tradeoffs between the hardware cost and the performance. The proposed architecture has been designed and verified by VerilogHDL and synthesized by Synopsys Design Compiler with a DongbuHitek $0.18{\mu}m$ STD cell library. The maximum operating frequency is 330MHz with 3,770 gates in equivalent two input NAND gates.

• International Journal of Precision Engineering and Manufacturing
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• v.7 no.4
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• pp.18-22
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• 2006

Although many efforts have been made in making nanometer-sized holes, there is still a major challenge in fabricating individual single-digit nanometer holes in a more controllable way for different materials, size distribution and hole shapes. In this paper we describe our efforts to use a top down approach in nanofabrication method to make single-digit nanoholes. There are three major steps towards the fabrication of a single-digit nanohole. 1) Preparing the freestanding thin film by epitaxial deposition and electrochemical etching. 2) Making sub-micro holes ($0.2{\mu}\;to\;0.02{\mu}$) by focused ion beam (FIB), electron beam (EB), atomic force microscope (AFM), and others methods. 3) Reducing the hole size to less than 10 nm by epitaxial deposition, FIB or EB induced deposition and micro coating. Preliminary work has been done on thin films (30 nm in thickness) preparation, sub-micron hole fabrication, and E-beam induced deposition. The results are very promising.

• Journal of Sensor Science and Technology
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• v.5 no.4
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• pp.9-15
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• 1996

In order to display magnetic signals obtained from a magneto-resistance sensor, a direct current magnetometer was designed and its circuit was constructed. The magnetic fields measured by the home-made magnetometer, which showed good functions of automatic ranging, analog output, and vector sensing, were well agreed with those by commercial MAG-01 magnetometer. The measurement range of the magnetometer was $1\;{\mu}T$ to 1.999 mT, the resolution was -132 dB within 1 Hz bandwidth and the measured magnetic fields could be displayed with $3{\cdot}1/2$-digit LED.

• Korean Journal of Occupational Health Nursing
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• v.6 no.1
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• pp.53-71
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• 1997

Across sectional study was performed to evaluate the chronic effects on central nerve system(CNS) of cumulative exposure of complex organic solvents, using neurobehavioral test. Subjects were 66 (male) dock yard painters of some large ship industry which is located in Ulsan. The neurobehavioral test battery used in this study was NCTB (Neurabehavioral Core Test Battery recommended by WHO(World Health Organization), which consisted of 7 items-Profile of mood states (POMS), Simple reaction time, Santa Ana dexterity test. Digit span, Digit symbol, Benton visual retention test and Pursuit aiming. The subjects were classified by 3 groups according to duration of employment(group 1 ; less than 9 years, group 2 ; 10-14 years, group 3 ; more than 15 years). The results of performance were analyzed considering of work duration, age, educational level, alcohol drinking, smoking and testing time as confounding factors. Benton visual retention test, pursuit aiming correct dot and sum of dot showed significant differences among the groups, and decreased with increasing work duration. It indicated that the mean scores of performance ability were lowering according to work duration. Besides, the tests that didn't show statistical significances but showed linear trends were depression-dejection, vigor, fatigue of POMS, slowest time of simple reaction time and digit span forward. Most of the neurobehavioral test items were correlated with age and educational level. After controlling of confounding factors-age and educational level, the results followed ; digit span backward was different significantly. Tension-anxiety, depression-dejection, anger-hostility of POMS, SD and slowest time of simple reaction time, Santa Ana dexterity test non-preferred hand, digit span forward, Benton visual retention test and pursuit aiming correct dot decreased with increasing of work duration. The correlation analysis was done in order to find out the relationship between subjective symptom and the scores of neurobehavioral core test battery. According to the results of analysis there were no items that had statistical significant relationship(p<0.05).