• 대한수학회논문집
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• 제35권1호
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• pp.83-116
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• 2020

Let G be a finite group. By a sequence over G, we mean a finite unordered sequence of terms from G, where repetition is allowed, and we say that it is a product-one sequence if its terms can be ordered such that their product equals the identity element of G. The large Davenport constant D(G) is the maximal length of a minimal product-one sequence, that is, a product-one sequence which cannot be factored into two non-trivial product-one subsequences. We provide explicit characterizations of all minimal product-one sequences of length D(G) over dihedral and dicyclic groups. Based on these characterizations we study the unions of sets of lengths of the monoid of product-one sequences over these groups.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1993년도 추계학술대회 논문집
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• pp.200-205
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• 1993

The automatic forming sequence design system can determine desirable operation sequences even if they have little experience in the design of cold forging process. This system is proposed,which generates forming sequence plans for the multistage cold forging of zxisymmetrical solid products. Since the process of metal forming can be considered as a transformation of geometry, treatment of the geometry of the product is a key in planning processes. Forming sequence for the part can be determined by means of primitive geometries such as cylinder,cone, convex, and concave. By utilizing this geometrical characteristics(diameter,height, and radius),the product geometry is expressed by a list of the pnmitive geometries. Accordingly, the forming sequence design is formulated as the search problem which starts with a billet geometry and finishes with a given product one. Using the developed system, the sequence drawing with all dimensions, which includes the proper sequence of operations for the part, is generated under the environment of AutoCAD. The preliminary choice of some feasible forming sequences can verify by using the finite element simulation.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제8권9호
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• pp.363-372
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• 2019

시퀀스란 두 항목 간의 순서가 존재하는 데이터를 말하며, 고객 한 명이 구매한 상품들이 나열된 구매이력 데이터는 대표적인 시퀀스 데이터 중 하나이다. 일반적으로 모든 상품은 대분류/ 중분류/ 소분류와 같은 상품 분류 체계를 가지며, 서로 다른 상품이더라도 비슷하다면 그 특성에 따라 동일한 범주로 분류된다. 따라서 본 논문에서는 두 구매이력 시퀀스 비교 시 상품의 구매 순서를 고려할 뿐만 아니라, 비교하고자 하는 두 상품이 다르더라도 서로 동일한 상품 군에 속한다면 더 높은 유사도를 부여하여 계산한다. 특히 구매이력 시퀀스 유사도 계산 성능에 직접적인 영향을 미치는 시퀀스 유사도 측정 방법을 선택하기 위해 본 연구에서는 대표적인 시퀀스 간 유사도 측정 방법인 레벤슈타인 거리, 동적 타임 워핑 거리, 니들만-브니쉬 유사도의 성능을 비교하였으며, 항목간의 계층구조도 반영하여 계산하도록 확장하였다. 기존의 유사도 측정 방법의 경우 시퀀스 내 상품 비교 시 상품의 일치 유무에 따라 단순히 0 또는 1의 값을 부여하여 계산한다. 하지만 제안 방법의 경우 서로 다른 상품이더라도 두 상품 간의 연관정도를 다르게 부여하기 위하여 상품 분류 트리를 사용하여 0에서 1 사이의 값을 가지도록 세분화하였다. 실험을 통해 세 알고리즘에 제안 방법을 적용한 경우 기존 방법에 비하여 구매이력 시퀀스 간의 유사도를 더 정확히 측정함을 확인하였다. 또한 정확성 측정 비교 실험을 통해 동적 타임 워핑 유사도가 다른 두 유사도 측정 방법에 비하여 시퀀스 내 상품의 연관 정도를 고려할 뿐만 아니라 두 시퀀스의 길이가 다른 경우에도 좋은 성능을 보였기 때문에 구매이력 데이터에서 시퀀스 간의 유사도 비교 시 가장 적합한 측정 방법임을 확인하였다.

• 한국통신학회논문지
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• 제34권7C호
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• pp.635-639
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• 2009

본 논문에서는 행벡터의 집합이 이진 벡터합 연산에 관해 닫혀있는 모든 하다마드 (Hadmard) 행렬들은 서로 동치(equivalent) 임융 증명한다. 이를 이용하면, 최대길이 수열로부터 생성된 순회 (cyclic) 하다마드 행렬과 크로네커 (Kronecker) 곱에 의해 생성된 월쉬-하다마드 (Walsh-Hadamard) 행렬이 동치임을 간단히 보일 수 있다.

• 대한본초학회지
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• 제29권3호
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• pp.19-26
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• 2014

Objectives : Aucklandiae Radix (Muxiang) one of important herbal medicines in oriental medicine, is defined as the dried root of Aucklandia lappa (Asteraceae). Owing to the similarities in the morphology and name, Inulae Radix (Tu-Muxiang) and Vladimiriae Radix (Chuan-Muxiang) as well as Aristolochiae Radix (Qing-Muxiang) originated from other medicinal plants are often used as substitutes and/or adulterants of Aucklandiae Radix. Therefore, a reliable authentication of these herbal medicines is necessarily for the public health and prevention of misuse. Methods : 32 samples of medicinal plants supplying Aucklandiae Radix, Inulae Radix, Vladimiriae Radix, and Aristolochiae Radix were collected in Korea and China. The ITS (Internal transcribed spacer) nucleotide sequences of samples were determined. The PCR primers to amply DNA marker of each herbal medicine were designed basing on the specific ITS regions showing differences in the sequences among medicinal plants. Results : Primer set Al R/IS F designed in this work amplified 220 bp PCR product only in samples of Aucklandiae Radix. In contrast, primer set Ih F/IS R, Vs R/IS F, and AcR F1/Ac R amplified 250 bp product, 356 bp prouct, and 516 bp product respectively to identify Inulae Radix, Vladimiriae Radix, and Aristolochiae Radix. Conclusions : The primers designed basing on the nucleotide sequences of ITS regions appearing differenced in the sequences among medicinal plants amplified the DNA markers for the identification of Aucklandiae Radix, Inulae Radix, Vladimiriae Radix, and Aristolochiae Radix. These herbal medicines were more efficiently identified by multiplex PCR method using all primers in a single PCR process.

• Nuclear Engineering and Technology
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• 제46권6호
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• pp.825-836
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• 2014

Predicting radioactive fission product (FP) behaviors in the reactor coolant system and the containment of a nuclear power plant (NPP) is one of the major concerns in the field of reactor safety, since the amount of radioactive FP released into the environment during the postulated accident sequences is one of the major regulatory issues. Radioactive FPs circulating in the primary coolant loop and released into the containment are basically in the form of gas or aerosol. In this study, a multi-component and multi-sectional analysis module for aerosol fission products has been developed based on the MAEROS model [1,2], and the aerosol transport model has been developed and verified against an analytic solution. The deposition of aerosol FPs to the surrounding structural surfaces is modeled with recent research achievements. The developed aerosol analysis model has been successfully validated against the STORM SR-11 experimental data [3], which is International Standard Problem No. 40. Future studies include the development of the resuspension, growth, and chemical reaction models of aerosol fission products.

• Journal of applied mathematics & informatics
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• 제30권1_2호
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• pp.93-100
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• 2012

In this paper, we present a strongly convergent parallel projection algorithm by introducing some parameter sequences for convex feasibility problem. To prove the strong convergence in a simple way, we transmit the parallel algorithm in the original space to an alternating one in a newly constructed product space. Thus, the strong convergence of the parallel projection algorithm is derived with the help of the alternating one under some parametric controlling conditions.

• 제어로봇시스템학회논문지
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• 제1권2호
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• pp.112-118
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• 1995

In designing assembly lines, it is required that the lines should not only meet the demand of the product, but also minimize the assembly cost associated with the line. For such a purpose, numerous research efforts have been made on either the assembly sequence generation or the assembly line balancing. However, the works dealing with both the research problems have been seldom reported in literature. When assembly sequences are generated without consideration of line balancing, additional cost may be incurred, because the sequences may not guarantee the minimum number of workstations. Therefore, it is essential to consider line balancing in the generation of cost-effective assembly sequences. To incorporate the two research problems into one, this paper treats a single-model and deterministic (SMD) assembly line balancing (ALB) problem, and proposes a new method for generating line-balanced robotic assembly sequences by using a simulated annealing. In this method, an energy function is derived in consideration of the satisfaction of assembly constraints, and the minimization of both the assembly cost and the idle time. Then, the energy function is iteratively minimized and occasionally perturbed by the simulated annealing. When no further change in energy occurs, an assembly sequence with consideration of line balancing is finally found. To show the effectiveness of the proposed scheme, a case study for an electrical relay is presented.

• International Journal of Industrial Entomology and Biomaterials
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• 제4권2호
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• pp.155-162
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• 2002

Cytochrome P45O (CYP) gene has been known to play one of the most important roles in metabolizing the exogenous materials. In insect, CYP is particularly known to detoxify toxic materials by adding oxygen molecule to the hydrophobic region of the materials. Thus, CYP-dependent metabolism is associated with the adaptation of insect to host plant chemicals. This in turn is known to be one of the driving forces for CYP diversification. In the present study, we cloned seven gene fragments of CYP 4 (CYP4) family from the midgut of the beet armyworm, Spodoptera exigua, through RT.PCT, Sequence analysis of the product showed the gene fragment to contain an open reading frame of ~150 amino acids, consisted of ~450 bp. The cloned gene fragments contained typical, conserved regions found in CYP4 family. Pairwise comparison of the deduced amino acid sequences among seven clones ranged in divergence from 0% to 52.86% and resulted in five distinct clones. The other two clones were identical or differ by one amino acid respectively to the corresponding clone, although each differed by ten nucleotides. Analysis of correlation between GenBank-registered, full length CYP4 and the cloned fragments resulted in statistically significant relationship ($r^{2}$ = 0.96085; p < 0.001), suggesting utility of the partial sequences as such full-length sequences. Phylogenetic analysis of the clones with GenBank-registered insect and mammal CYP4 family sequences by parsimony and several distance methods subdivided the clones into two groups: tones belonging to CYP4S and the others to CYP4M families.

• 대한수의학회지
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• 제41권1호
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• pp.59-65
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• 2001

To clarify for the presence of infectious bronchitis virus (IBV) in Korea before 1986, in which the virus was first isolated, materials collected from chicken diagnostic consignments between 1980 and 1985 and propagated in chicken embryos or cell cultures were screened by the reverse transcriptase polymerase chain reaction (RT-PCR) targeted to the nucleocapsid gene of the virus. Among 11 samples examined, one sample (IBV-SNU80108) submitted in 1980 showed specific PCR product (281 bp). When the amplified product was sequenced, together with IBV vaccine virus H120 strain, and compared with the data for ten other IBV strains derived from the GeneBank, identities between IBV-SNU80108 and other strains in nucleotide and amino acid sequences ranged 96.3% to 63.7% and 96.4% to 69%, respectively. IBV-SNU80108 was distinct from H120 strain by showing 91.9% and 92.9% identities in the respective sequences. This data suggested that IBV genetically distinctive from other foreign IBV strains might be present before 1986 in Korea.