• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.3
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• pp.45-50
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• 2008

The choice of an irreducible polynomial and the representation of elements have influence on the efficiency of operators for finite fields. This paper suggests two serial multiplier for the extention field GF$(p^n)$ where p is odd prime. A serial multiplier using an irreducible binomial consists of (2n+5) resisters, 2 MUXs, 2 multipliers of GF(p), and 1 adder of GF(p). It obtains the mulitplication result after $n^2+n$ clock cycles. A serial multiplier using an AOP consists of (2n+5) resisters, 1 MUX, 1 multiplier of CF(p), and 1 adder of GF(p). It obtains the mulitplication result after $n^2$+3n+2 clock cycles.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.9
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• pp.3841-3857
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• 2020

RSA is one of the best well-known public key cryptosystems. This methodology is widely used at present because there is not any algorithm which can break this system that has all strong parameters within polynomial time. However, it may be easily broken when at least one parameter is weak. In fact, many weak parameters are already found and are solved by some algorithms. Some examples of weak parameters consist of a small private key, a large private key, a small prime factor and a small result of the difference between two prime factors. In this paper, the new weakness of RSA is proposed. Assuming Euler's totient value, Φ (n), can be rewritten as Φ (n) = ad + b, where d is the private key and a, b ∈ ℤ, if a divides both of Φ (n) and b and the new exponent for the decryption equation is a small integer, this condition is assigned as the new weakness for breaking RSA. Firstly, the specific algorithm which is created for this weakness directly is proposed. Secondly, two equations are presented to find a, b and d. In fact, one of two equations must be implemented to find a and b at first. After that, the other equation is chosen to find d. The experimental results show that if this weakness has happened and the new exponent is small, original plaintext, m, will be recovered very fast. Furthermore, number of steps to recover d are very small when a is large. However, if a is too large, d may not be recovered because m which must be always written as m = h^a is higher than modulus.

• Fisheries and Aquatic Sciences
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• v.24 no.3
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• pp.129-137
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• 2021

Dietary protein requirements of abalone (Haliotis discus) depending on abalone size were determined and compared. One thousand and fifty small abalone (initial weight of 2.7 g) and five hundred forty large one (initial weight of 16.0 g) were distributed into 15 and 18 containers in Trial 1 and 2, respectively. Five and six experimental diets containing crude protein level from 20% to 40% and 20% to 45% with 5% increment of protein level for the small and large abalone were prepared and referred to as the CP20, CP25, CP30, CP35, CP40, and CP45 diets, respectively. The experimental diets were fed to abalone for 16 weeks in Trials 1 and 2. Specific growth rate (SGR) of the small abalone fed the CP20 diet was lower compared to that of abalone fed all other diets in Trial 1. Growth performance (weight gain and SGR) of the large abalone fed the CP30, CP35, and CP40 diets were greater than that of abalone fed the CP20, CP25, and CP45 diets in Trial 2. Dietary protein requirements were estimated to be 33.0% and 33.5% for the small and large abalone based on the 2^nd order polynomial analysis, respectively. Dietary protein requirements for the small abalone grown from 2.7 g to 7.4 g and the large one grown from 16 g to 21 g were estimated to be 33.0% and 33.5%, respectively. Size differences in abalone did not affect dietary protein requirement under this experimental conditions.

• Nuclear Engineering and Technology
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• v.50 no.1
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• pp.18-24
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• 2018

This study proposes a new method of analyzing the burnup credit in boiling water reactor spent fuel assemblies against various operating parameters. The operating parameters under investigation include fuel temperature, axial burnup profile, axial moderator density profile, and control blade usage. In particular, the effects of variations in one and two operating parameters on the curve of effective multiplication factor ($k_{eff}$) versus burnup (B) are, respectively, the so-called single and compound effects. All the calculations were performed using SCALE 6.1 together with the Evaluated Nuclear Data Files, part B (ENDF/B)-VII238-neutron energy group data library. Furthermore, two geometrical models were established based on the General Electric (GE)14 $10{\times}10$ boiling water reactor fuel assembly and the Generic Burnup-Credit (GBC)-68 storage cask. The results revealed that the curves of $k_{eff}$ versus B, due to single and compound effects, can be approximated using a first degree polynomial of B. However, the reactivity deviation (or changes of $k_{eff}$, ${\Delta}k$) in some compound effects was not a summation of the all ${\Delta}k$ resulting from the two associated single effects. This phenomenon is undesirable because it may to some extent affect the precise assessment of burnup credit. In this study, a general formula was thus proposed to express the curves of $k_{eff}$ versus B for both single and compound effects.

• Korean Journal of Health Education and Promotion
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• v.13 no.2
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• pp.130-166
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• 1996

As compared with body height and body weight by ages and sexes, by means of the data reported under other researchers from 1967 to 1994 for 33 years, this study obtained the estimate value of body height and body weight by ages and sexes for the same period, and figured out prediction value of body height and body weight in the ages of between 6 and 14 from 1995 to 2000. These surveys and measurements took for one year from October 1st 1994 to September 30th. As shown in the 〈Table 1〉, in order to calculate the establishment, estimate value and prediction value of the chronological regression model of body height and body weight, by well-grounded 17 representative research papers, this research statistically tested propriety of liner regression model by the residual analysis in advance of being reconciled to simple liner regression model by the autonomous variable-year and the subordinate variable-body weight and measured prediction value, theoretical value from 1962 to 1994 by means of 2nd or 3rd polynomial regression model, with this redult did prediction value from 1995 to 2000. 1. Chronological Change of Body Height and Body Weight The analysis result from regression model of the chronological body height and body weight for the aged 6 - 16 in both sexes ranging from 1962 to 1994, corned from the 〈Table 2-20〉. On the one hand, the measurement value of respective researchers had a bit changes by ages with age growing, but the other hand, theoretical value, prediction value showed the regular increase by the stages and all values indicated a straight line on growth and development with age growing. That is, in case of the aged 6, males had 109.93cm in 1962 and females 108.93cm, but we found the increase that males had 1I8.0cm, females 1I3.9cm. In theoretical value, prediction value, males showed the increase from 109.88cm to 1I7.89cm and females from 109.27cm to 1I5.64cm respectively. There was the same inclination toward all ages. 2. Comparision to Measurement Value and Prediction Value of Body Height and Body Weight in 1994 As shown in the 〈Table 21〉, in case of body height, measurement value and prediction value of body height and body weight by ages and sexes almost showed the similiar inclination and poor grade, in case of body weight, prediction value in males had a bit low value by all ages, and prediction value in females had a high value in adolescence, to the contrary, a low value in adult. 3. Prediction Value of Body Height and Body Weight from 1995 to 2000 This research showed that body height and body weight remarkably increased in adolescence but slowly in adult. This study represented that Korean physique was on the increase and must be measured continually hereafter.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.1
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• pp.37-42
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• 2024

This paper suggests polynomial time algorithm for cutwidth minimization problem that classified as NP-complete because the polynomial time algorithm to find the optimal solution has been unknown yet. To find the minimum cutwidth CW_f(G)=max_𝜈∈_VCW_f(𝜈)for given graph G=(V,E),m=｜V｜, n=｜E｜, the proposed algorithm divides neighborhood N_G[𝜈_i] of the maximum degree vertex 𝜈_i in graph G into left and right and decides the vertical cut plane with minimum number of edges pass through the vertex 𝜈_i firstly. Then, we split the left and right N_G[𝜈_i] into horizontal sections with minimum pass through edges. Secondly, the inner-section vertices are connected into line graph and the inter-section lines are connected by one line layout. Finally, we perform the optimization process in order to obtain the minimum cutwidth using vertex moving method. Though the proposed algorithm requires O(n²) time complexity, that can be obtains the optimal solutions for all of various experimental data

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.2
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• pp.23-29
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• 2012

Existing pedestrian and evacuation models generally seek to find locally optimal solutions for the shortest or the least time paths to exits from individual locations considering pedestrian's characteristics (eg. speed, direction, sex, age, weight and size). These models are not designed to produce globally optimal solutions that reduce the total evacuation time of the entire pedestrians in a building when all of them evacuate at the same time. In this study, we suggest a globally optimal model for indoor pedestrian evacuation to minimize the total evacuation time of occupants in a building considering different distributions of them. We used the genetic algorithm, one of meta-heuristic techniques because minimizing the total evacuation time can not be easily solved by polynomial expressions. We found near-optimal evacuation path and time by expressing varying pedestrians distributions using chromosomes and repeatedly filtering solutions. In order to express and experiment our suggested algorithm, we used CA(cellular automata)-based simulator and applied to different indoor distributions and presented the results.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.4
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• pp.915-922
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• 2014

This study was conducted to evaluate the optimum dietary protein level in juvenile river puffer. Five semi-purified diets were formulated by using casein to contain graded levels of protein levels of 35, 45, 50, 55 and 65%. Fish averaging $8.56{\pm}0.04g$ were randomly assigned to one of five experimental diets in triplicate groups for 8 weeks. After the 8-weeks of feeding trial, weight gain and feed efficiency of fish fed 45, 50 and 55% diets were significantly higher than those of fish fed 35 and 65% diets (P<0.05). Protein efficiency ratio of fish fed the 35% diet was significantly higher than those of fish fed 65% diet (P<0.05), but there were no significant difference among those of fish fed 45, 50 and 55% diets. Specific growth rate of fish fed 50% diet was significantly higher than those of fish fed 35 and 65% diets (P<0.05), but there was no significant difference among those of fish fed 45, 50 and 55% diets. No significant differences were observed in condition factor, hepatosomatic index, visceralsomatic index and survival among those of fish fed all the diets. Optimum dietary protein levels by using broken-line model and by using second order polynomial were estimated at 45.9% and 51.6% for the maximum growth of fish respectively. Therefore, these results suggested that the optimum dietary protein level could be greater than 45.9% but less than 51.6% for the maximum growth in juvenile river puffer.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.6
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• pp.24-30
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• 2003

This study focuses on the arithmetical methodology and hardware implementation of low system-complexity A $B^2$＋C operator over GF(2$^{m}$ ) using the irreducible AOP of degree m. The proposed parallel-in parallel-out operator is composed of CS, PP, and MS modules, each can be established using the array structure of AND and XOR gates. The proposed multiplier is composed of (m＋1)$^2$ 2-input AND gates and (m＋1)(m＋2) 2-input XOR gates. And the minimum propagation delay is $T_{A}$ ＋(1＋$\ulcorner$lo $g_2$$^{m}$ $\lrcorner$) $T_{x}$ . Comparison result of the related A $B^2$＋C operators of GF(2$^{m}$ ) are shown by table, It reveals that our operator involve more lower circuit complexity and shorter propagation delay then the others. Moreover, the interconnections of the out operators is very simple, regular, and therefore well-suited for VLSI implementation.

• Journal of Biomedical Engineering Research
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• v.23 no.5
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• pp.365-373
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• 2002

Accurate localization of target lesion is required to protect normal peripheral tissue and irradiate exactly to tumors in stereotactic radiosurgery(SRS). Digital angiography is one of the most effective diagnostic tools to detect and identify the target tumors. However, it shows pincushion distortion due to the characteristics of the image intensifier. We have implemented a simulation study for the correction of distortion using the geometric transformation. Phantom images were produced transformation. In conclusion, the geometric transformation could effectively be used for the pincushion distortion of image intensifier and there was no significant different between two methods indicating 2% correction error from the ideal image in all cases.