• Journal of the Korean Mathematical Society
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• v.42 no.1
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• pp.135-151
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• 2005

In this paper, we obtain some properties of the sequences $U^{q}_n\;and\;V^{q}_n$ introduced in [6]. We find polynomial representations and formulas of them. For q = 5, $U^{5}_n$ is the Fibonacci sequence $F_n\;and\;V^{5}_n$ is the Lucas sequence $L_n$.

• Communications of the Korean Mathematical Society
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• v.32 no.3
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• pp.511-522
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• 2017

We explicitly solve the diophantine equations of the form $$A_{n_1}A_{n_2}{\cdots}A_{n_k}{\pm}1=B^2_m$$, where $(A_n)_{n{\geq}0}$ and $(B_m)_{m{\geq}0}$ are either the Fibonacci sequence or Lucas sequence. This extends the result of D. Marques [9] and L. Szalay [13] concerning a variant of Brocard-Ramanujan equation.

• Journal of the Chungcheong Mathematical Society
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• v.31 no.3
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• pp.333-341
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• 2018

In this paper we introduce the concept of equi-integrability of sequence of the fuzzy number-valued AP-Henstock-Stieltjes integrable functions. Under this concept, we prove two convergence theorems for sequences of the fuzzy number-valued AP-Henstock-Stieltjes integrable functions.

• Composites Research
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• v.25 no.5
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• pp.141-146
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• 2012

The strength design for the lightweight bicycle wheel made of the Carbon/Epoxy composite laminates has been discussed in this paper. For bicycle wheel design, lightness of the wheel is important. Also, it has to satisfy the required strength under specific loading cases. Two testing methods for the bicycle wheel, i.e. vertical and complex loadings, are adopted in this study. Because the strengths of composite wheel is different in relation to the stacking sequence and the number of plies, it is important to decide an appropriate stacking sequence and number of layers for the composite wheel. From the finite element analysis results, the most stable sequence orientation and number of layers are determined. The stacking sequence $[0]_{8n}$, $[90]_{8n}$, $[0/90]_{2ns}$, $[{\pm}45]_{2ns}$, $[0/{\pm}45/90]_{ns}$ (n=1,2,3,4)are performed for finite element analysis. From results, $[0/{\pm}45/90]_{3s}$ lay-up is a good selection for the composite bicycle wheel. Also, the weakest point and layer are found in this study.

• Journal of IKEEE
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• v.24 no.1
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• pp.40-45
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• 2020

In this paper, we consider an efficient design of quantizers at sensor nodes for sequence-based localization (SBL) systems which recently show a competitive performance for in-door positioning, Since SBL systems locate targets by partitioning the sensor field into subregions, each with an unique sequence number, we use the distance samples between sensors and the sequences for quantizer design in order to propose a low weight design process. Furthermore, we present a new cost function devised to assign the number of samples and the number of unique sequences uniformly into each of quantization partitions and design quantizers by searching the quantization partitions and codewords that minimize the cost function. We finally conduct experiments to demonstrate that the proposed algorithm offers an outstanding localization performance over typical designs while maintaining a substantial reduction of design complexity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.5049-5057
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• 2010

As communication technologies are developed and variety of services to mobile devices are provided, mobile users is rapidly increasing every year. However, mobile services running on wireless network environment are exposed to various security threats, such as illegal tampering, eavesdropping, and disguising identity. Accordingly, the secure mobile communications services to 3GPP were established that the standard for 3GPP-AKA specified authentication and key agreement. But in the standard, sequence number synchronization problem using false base station attack and privacy problem were discovered through related researches. In this paper, we propose an efficient authentication mechanism for enhanced privacy protection in the 3G network. We solve the sequence number synchronization existing 3GPP authentication scheme using timestamp and strengthen a privacy problem using secret token. In addition, the proposed scheme can improve the bandwidth consumption between serving network and home network and the problem of authentication data overhead for the serving network because it uses only one authentication vector.

• Journal of Microbiology and Biotechnology
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• v.26 no.10
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• pp.1800-1807
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• 2016

To understand how human cytomegalovirus (HCMV) might change and evolve after reactivation, it is very important to understand how the nucleotide sequence of cultured HCMV changes after in vitro passaging in cell culture, and how these changes affect the genome of HCMV and the consequent variation in amino acid sequence. Strain JHC of HCMV was propagated in vitro for more than 40 passages and its biological and genetic changes were monitored. For each passage, real-time PCR was performed in order to determine the genome copy number, and a plaque assay was employed to get virus infection titers. The infectious virus titers gradually increased with passaging in cell culture, whereas the number of virus genome copies remained relatively unchanged. A linear correlation was observed between the passage number and the log₁₀ infectious virus titer per virus genome copy number. To understand the genetic basis underlying the increase in HCMV infectivity with increasing passage, the whole-genome DNA sequence of the high-passage strain was determined and compared with the genome sequence of the low-passage strain. Out of 100 mutations found in the high-passage strain, only two were located in an open reading frame. A G-T substitution in the RL13 gene resulted in a nonsense mutation and caused an early stop. A G-A substitution in the UL122 gene generated an S-F nonsynonymous mutation. The mutations in the RL13 and UL122 genes might be related to the increase in virus infectivity, although the role of the mutations found in noncoding regions could not be excluded.

• Journal of The Korean Association For Science Education
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• v.19 no.4
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• pp.645-652
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• 1999

The effects of number, source, and sequence of analogs on middle school students' concept recall and application were investigated. Based on the number (one/two) and source(everyday/science) of analogs, four types of learning materials were developed and pilot-tested. Prior to the treatment the field dependence/independence (FD/l) test was administered and the scores were used as a blocking variable. The learning materials were read by randomly assigned middle school students (N=88), and the concept recall and application test was administered immediately and four weeks later. In the immediate and retention tests, there were no significant main effects of number, source, and sequence of analogs. In the application problems of retention test. however, there were some significant interaction effects with students' FD/I. Field-independent students who learned with two analogs scored significantly higher than those who learned with one analog. In the case of using two analogs, field-dependent students who learned with everyday-analog first scored significantly higher than those who learned with science-analog first.

• School Mathematics
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• v.18 no.1
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• pp.175-191
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• 2016

In the elementary school mathematics textbook that has been revised in 2013, the instructional sequence for teaching addition and subtraction, which had remained unchanged for three decades since 1982, was finally changed in 2013. Particularly, the addition and subtraction of two-digit numbers without regrouping, such as 72+25=97 or 85-24=61, are taught earlier than the composing and decomposing of the number 10 using other numbers. This study examines the appropriacy and validity of these changes. However, the reason for these changes in the national curriculum or teacher's guide could not be determined. Further, several references emphasize the addition of two single-digit numbers, such as 7+8=15, and the subtraction of a single-digit number from a number between 11 and 19, such as 16-9=7, as basic facts. In other countries' textbooks, the teaching of addition and subtraction up to the number 20 is prioritized before teaching the addition and subtraction of two-digit numbers without regrouping. The results of this study indicate that these changes in the instructional sequence in the textbook that was revised in 2013 need to be reconsidered.

• Journal of the Korean Data and Information Science Society
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• v.13 no.2
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• pp.77-85
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• 2002

The statistical testing methods have been widely recognized to determine the plain and cipher texts. In fact, the randomness for a sequence from an encryption algorithm is necessary to guarantee security and reliance of cipher algorithm. Thus, the statistical randomness tests are used to discover cipher text. In this paper, we would provide the critical value for an approximate entropy test by estimating the nonlinear regression equation when the number of sequence and the level of significance are given. Thus, we can discern plan and cipher text for real problem with given number of sequence and the level of significance. Also, we confirm the fitness of the estimated critical values from the rate of success for plain or cipher text.