• 한국산학기술학회논문지
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• 제14권3호
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• pp.1388-1392
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• 2013

전동스쿠터는 수명이 짧고 효율이 낮은 직류 모터를 사용하고 있으며, 모터를 제어하기 위한 시스템을 일률적으로 수입하여 장착하고 있어 제품의 차별화가 없고 다양한 특성을 갖는 장애인에 맞는 제품을 디자인 할 수 없는 문제점을 가지고 있다. 따라서 본 연구에서는 장애인용 전동스쿠터에 특화시켜 가격은 저렴하면서도 반영구적인 수명 그리고 고출력의 특징을 갖는 BLDC 모터 제어시스템을 개발하였다. 특히, 국내 외 업체에서 생산되고 있는 전동스쿠터와는 차별화된 고출력, 고효율 전동스쿠터 제어시스템를 개발함으로써 국내산 전동스쿠터의 기술대비 가격 경쟁력을 확보할 수 있을 뿐만 아니라 관련 산업의 활성화에도 기여할 수 있을 것이다.

• 산업경영시스템학회지
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• 제45권3호
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• pp.78-89
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• 2022

The purpose of this study was to propose useful suggestion by analyzing preventive replacement policy under which there are minor and major failure. Here, major failure is defined as the failure of system which causes the system to stop working, however, the minor failure is defined as the situation in which the system is working but there exists inconvenience for the user to experience the degradation of performance. For this purpose, we formulated an expected cost rate as a function of periodic replacement time and the number of system update cycles. Then, using the probability and differentiation theory, we analyzed the cost rate function to find the optimal points for periodic replacement time and the number of system update cycles. Also, we present a numerical example to show how to apply our model to the real and practical situation in which even under the minor failure, the user of system is not willing to replace or repair the system immediately, instead he/she is willing to defer the repair or replacement until the periodic or preventive replacement time. Optimal preventive replacement timing using two variables, which are periodic replacement time and the number of system update cycles, is provided and the effects of those variables on the cost are analyzed.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.220-220
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• 2022

Disproportionating Enzyme 1 (DPE1) is an a-1,4-D-glucanotransferase that cleavages the a-1,4-glucosidic bonds and transfers glucosyl groups. In rice endosperm, it participates in starch synthesis by transferring maltooligosyl groups from amylose and amylopectin to amylopectin. Here, we investigated the haplotype variations and evolutionary indices (e.g., genetic diversity and population structure) for the DPE1 gene in 374 rice accessions representing seven subgroups (wild, indica, temperate japonica, tropical japonica, aus, aromatic, and admixture). Variant calling analysis of DPE1 coding regions leads to the identification of six functional haplotypes representing/occupying 8 nonsynonymous SNPs. Nucleotide diversity analysis revealed the highest pi-value in wild group (0.0556) compared to other cultivated groups, of which temperate japonica showed the most reduction of genetic diversity value (0.003). A significant positive Tajima's D value (1.6330) of admixture highlights sudden population contraction under balancing selection, while temperate japonica with the lowest Tajima's D value (-1.3523) showed a selection signature of DPE1 domestication which might be the cause of excess of rare alleles. Moreover, these two subpopulations exhibits a greater differentiation (F_ST=0.0148), indicating a higher genetic diversity. Our findings on functional DPE1 haplotypes will be useful in future breeding programs, and the evolutionary indices can also be applicable in functional studies of the DPE1 gene.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.217-217
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• 2022

Pullulanase (PUL), a debranching enzyme, has been utilized in hydrolyzing the a-1,6 glucosidic linkages in starch, amylopectin, pullulan, as well as related oligosaccharides. It has also been indicated that PUL is a novel indicator of inherent RS (Resistant Starch) formation in rice. In this study, we performed haplotype analysis on 320 bred rice accessions, and additional 54 wild accessions were added to study genetic diversity along with other population-based analyses of the PUL gene. Through these investigations, we summarized a total of 10 functional (non-synonymous) SNPs from 7 different exons on chromosome 4. There were 10 haplotypes, of which only six haplotypes were functional, implicating different subpopulations. Diversity reduction was noticed in temperate japonica (0.0005) compared to the highest one (aus, 0.0154), illustrating their higher genetic differentiation by F_ST-value (0.926). The highest Tajima^ D value was observed in indica (3.6613), indicating PUL gene domestication signature under balancing selection, while the lowest Tajima's D value was found in temperate japonica (-2.2191) which might have undergone under positive selection and purified due to the excess of rare alleles. PCA, population structure, and phylogenetic analyses provide information on the genetic relatedness between and or among the cultivated subpopulations and the wild based on PUL genomic region.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.218-218
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• 2022

Granules-bound starch synthase II (GBSSII), one of the isoforms of granule-bound starch synthase (GBSS), is responsible for amylose synthesis by expressing in non-storage tissues such as leaf, stem, root, and pericarp. Up to date, little is known about this gene functions and basic knowledge of heritable characteristics of this gene, GBSSII. We identified functional haplotypes and performed evolutionary analyses on the GBSSII using 374 rice accessions (320 Korean bred and 54 wild) based on the classified groups. A total of 14 haplotypes were found, and almost all haplotypes (13) were functional, carrying 19 non-synonymous SNPs in two exons (exons 1 and 2). The lowest nucleotide diversity was detected in Tropical japonica (0.00145), while the highest pi-value was in Aus (0.01081), illustrating the signal of this gene evolution. The highest Tajima's D value in Aus (1.6380) indicates GBSSII gene domestication signature under balancing selection, while the lowest Tajima's D value in Temperate japonica (-0.8243) highlights that they were under positive selection, which may be purified due to the excess of rare alleles. The highest genetic differentiation was observed between Tropical japonica and aroma (F_ST = 0.921928). In contrast, the highest interbreed level was detected in Aus-admixture (F_ST = -0.20157). The genetic relatedness between and or among the wild and cultivated subpopulations was revealed through PCA, population structure, and phylogenetic analyses.

• 한국콘텐츠학회논문지
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• 제20권6호
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• pp.406-414
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• 2020

수출은 해외 신규시장 개척을 가능케 하여 내수시장의 의존성을 줄여주는 역할을 한다. 또한 기업의 전략적 수단으로써 수출은 국가의 성장에 기여할 뿐 아니라 기업의 규모의 경제, 범위의 경제, 경험효과를 최대한 이용할 수 있는 기회를 제공한다. 실제로 내수시장의 성장 한계와 해외 시장에 대한 정보기술의 발달로 많은 기업들이 수출을 통해 해외 시장으로의 진출을 촉진시키고 있다. 본 논문은 대구에 위치한 기업들을 대상으로 산업조직론적 관점과 전략관점에 근거하여 각 변수들이 수출에 미치는 영향에 대해서 분석하였다. 산업조직론적 관점에서의 실증분석 결과를 살펴보면, 제도적 협력과 정부지원이 기업의 수출에 유의적으로 긍정적인 영향을 미치는 것으로 나타났으며, 수출성과에는 제도적 협력만이 긍정적인 영향을 미치고 있음을 알 수 있었다. 전략관점에서는 제품차별화, 해외수출망, 해외진출 국가 수가 수출에 긍정적인 영향을 미치는 것으로 나타났으며, 수출성과에는 해외수출망, 해외진출 국가 수가 긍정적인 영향을 미치는 것으로 나타났다.

• 한국약용작물학회지
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• 제24권4호
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• pp.317-322
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• 2016

Background: In the herbal medicine market, Angelica gigas, Angelica sinensis, and Angelica acutiloba are all called "Danggui" and used confusingly. We aimed to assess the genetic diversity and relationships among 14 Angelica species collected from different global seed companies. Toward this aim we developed DNA markers to differentiate the Angelica species. Methods and Results: A total of 14 Angelica species, A. gigas, A. acutiloba, A. sinensis, A. pachycarpa, A. hendersonii, A. arguta, A. keiskei, A. atropurpurea, A. dahurica, A. genuflexa, A. tenuissima, A. archangelica, A. taiwaniana, and A. hispanica were collected. The genetic diversity of all 14 species was analyzed by using five chloroplast DNA-based simple sequence repeat (SSR) markers and employing the DNA fragment analysis method. Each primer amplified 3 - 12 bands, with an average of 6.6 bands. Based on the genetic diversity analysis, these species were classified into specific species groups. The cluster dendrogram showed that the similarity coefficients ranged from 0.77 to 1.00. Conclusions: These findings could be used for further research on cultivar development by using molecular breeding techniques and for conservation of the genetic diversity of Angelica species. The analysis of polymorphic SSRs could provide an important experimental tool for examining a range of issues in plant genetics.

• 산업경영시스템학회지
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• 제42권2호
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• pp.1-8
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• 2019

Network externalities are essentially dynamic in that the value consumers feel about a product is affected by the size of the existing customer base that uses that product. However, existing studies on network externalities analyzed the effects of network externalities in a static way, not dynamic. In this study, unlike previous studies, the impact of network externalities on price competition in a vertically differentiated market is dynamically analyzed. To this end, a two-period duopoly game model was used to reflect the dynamic aspects of network externalities. Based on the game model, the Nash equilibria for price, sales volume, and revenue were derived and numerically analyzed. The results can be summarized as follows. First, if high-end product has strong market power, the high-end product vendor takes almost all benefits of the network externality. Second, when high-end product has strong market power, the low-end product will take over most of the initial sales volume increase. Third, when market power of high-end product is not strong, it can be seen that the effects of network externalities on the high and low-end products are generally proportional to the difference in quality. Lastly, if there exists a strong network externality, it is shown that the presence of low-end product can be more profitable for high-end product vendor. In other words, high-end product vendor has incentive to disclose some technologies for the market entrance of low-end product, even if it has exclusive rights to the technologies. In that case, however, it is shown that the difference in quality should be maintained significantly.

• ETRI Journal
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• 제26권6호
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• pp.641-646
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• 2004

As the use of signatures for identification purposes is pervasive in society and has a long history in business, dynamic signature verification (DSV) could be an answer to authenticating a document signed electronically and establishing the identity of that document in a dispute. DSV has the advantage in that traits of the signature can be collected on a digitizer. The research question of this paper is to understand how the individual variables vary across devices. In applied applications, this is important because if the signature variables change across the digitizers this will impact performance and the ability to use those variable. Understanding which traits are consistent across devices will aid dynamic signature algorithm designers to create more robust algorithms.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.355-357
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• 2004

In this paper, to calculate accurate remaining volume, it presents how to figure out nickel-cadmium battery algorithm. A nickel-cadmium battery has widely been used in industrial field and to military. Recent high demands on the battery caused 'How to calculate accurate remaining volume is very important task to be solved. In this paper, it says it is useful using the terminal voltage change of the resistance that can be connected with the battery and the differentiation of the terminal voltage to calculate remaining volume of nickel-cadmium battery. And these can be used for volume inference data so that it is fuzzy based system which can be helpful to inference the remaining volume by the resistance of terminal voltage change. Because of electrochemical complexity, the volume calculating system is inferencing undirectly by experimentally built DB where as current the existing volume models are suffering to be adapted.