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        28.
        2020.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Recently, a study of prognosis and health management (PHM) was conducted to diagnose failure and predict the life of air craft engine parts using sensor data. PHM is a framework that provides individualized solutions for managing system health. This study predicted the remaining useful life (RUL) of aeroengine using degradation data collected by sensors provided by the IEEE 2008 PHM Conference Challenge. There are 218 engine sensor data that has initial wear and production deviations. It was difficult to determine the characteristics of the engine parts since the system and domain-specific information was not provided. Each engine has a different cycle, making it difficult to use time series models. Therefore, this analysis was performed using machine learning algorithms rather than statistical time series models. The machine learning algorithms used were a random forest, gradient boost tree analysis and XG boost. A sliding window was applied to develop RUL predictions. We compared model performance before and after applying the sliding window, and proposed a data preprocessing method to develop RUL predictions. The model was evaluated by R-square scores and root mean squares error (RMSE). It was shown that the XG boost model of the random split method using the sliding window preprocessing approach has the best predictive performance.
        4,000원
        30.
        2018.10 구독 인증기관·개인회원 무료
        In order to accumulate the ecological information of Drosophila suzukii for export negotiations of domestic strawberry, we weekly monitored occurrence of D. suzukii at three strawberry fields located in Gok-seong, Dam-yang and Hwa-sun using the best combination of trap and attractant from November 2017 to May 2018, the period of strawberry production. Monitoring was carried out at three sites (a hill located 150 meter distant to greenhouse, outside greenhouse and inside greenhouse) in Gok-seong. Drosophil suzukii was trapped at three short periods from November to the beginning of December, from the end of December to the beginning of January, and from April in a hill. At outside greenhouse, D. suzukii was trapped at two short periods from November to the early December and the beginning of May. In inside greenhouse, it occurred once after May 24th. Gok-seong data can be summarized as more occurrence for longer period as the distance to greenhouse increases. Dam-yang occurred once in a short period inside greenhouse and hill, respectively on May. In case of Hwa-sun, D. suzukii did not trapped in whole trapping sites during trapping period, except for the surrounding grape and peach cultivation areas at the end of November. Summarized, no occurrence periods are from November 20th, 2017 to May 14th, 2018 inside greenhouse; from December 11th, 2017 to May 3rd, 2018 outside greenhouse; and from January 8th, 2018 to April 12th, 2018 on a hill. In connection with strawberry culture, the D. suzukii tends to occur at the beginning and the end of the strawberry production period. We expect this result can serve as a helpful data for export negotiation for quarantine.
        31.
        2018.10 구독 인증기관·개인회원 무료
        The yellow-legged hornet, Vespa velutina nigrithorax (Hymenoptera: Vespidae), invaded into South Korea in 2003. Currently, V. velutina is distributed throughout South Korean regions,. A genetic trait of invasive species provides important data for environmental risk assessment. In this study, we analysed the genetic variation of the V. velutina among the populations of South Korea and other foreign countries using partial sequences of mitochondrial COI, CytB and 16S rRNA. We further developed intergenic spacers (IGS2 and IGS3) to detect genetic variation among Korean populations. Each single haplotype was recovered from the domestic V. velutina from each coding gene sequence. Korean individuals shared the haplotype with that of Japan and China. Phylogenetic analysis (excluding 16S rRNA) using available sequences and ours showed the presence of two groups: the Indonesia and Malaysia group and another group (Korea, Japan, China, France, Vietnam and Thailand). The newly developed IGS2 and IGS3 markers resulted in each seven and four haplotypes, providing better resolution than coding gene sequences. Analysis of Molecular Variance using the combined sequences of IGS2 and IGS3 showed that the majority of variance was allocated to each population and only minority of variance is allocated to among-populations. This result may indicate that the V. v. nigrithorax invaded in Korea shows a single panmictic population and this possibly suggest that Korean population may have originated from small founder individuals.
        32.
        2018.05 구독 인증기관·개인회원 무료
        Roads in Korea are equipped with PMS (Pavement Management System) computation data that runs on highway, national highway and municipal road. PMS is a program that selects and manages the road pavement optimal maintenance alternative as a indicator of the road pavement structural and functional performance. PMS is a system that has been developed for the primary purpose of maintaining the structural performance of road pavement, and so far does not include any indicators associated with the safety of road users. However, the road cave-in, which have recently become an issue on social networking sites, mass-media, and other issues, should pose systematically because it can make a safety risk to road users, and in particular lead to the structural and functional failure of the PMS program in view of the road pavement. Accordingly, this research has developed a practical use case for developing an integrated road cave-in management program based on the results of various studies on the exploration, analysis, assessment and handling of the existing road cave-in in Korea.
        33.
        2018.04 구독 인증기관·개인회원 무료
        동남아시아에 발생하던 등검은말벌은 최근 국내 뿐만 아니라 프랑스와 일본, 유럽 전역으로 확산되어 전 세계 양봉 산업에 극심한 피해를 주고 있다. 등검은말벌을 방제하기 위해 다양한 방제 방법들이 연구되고 있으며, 그 중 말벌 유인제에 대해 국제적으로 많은 연구가 진행되어 왔으나 이 역시 지속적인 개발이 필요한 실정이다. 따라서 본 연구에서는 시판 유인제와 최근 (주)다목에코텍에서 새롭게 개발한 신규 개발 유인제에 대한 효능 검정을 수행하였 고 양봉장에 출현하는 국내 발생 말벌속의 발생양상을 조사하였다. 담양 1개소와 곡성 2개소에 기존 유인제과 신규 유인제를 장착한 포획기를 각 3쌍씩 설치하여 2016년 9월부터 11월말까지 주 1~2회 관찰하였다. 그 결과 국내 발생 말벌속 중 등검은말벌(7,787 개체)이 가장 많이 포획되었고, 다음으로 장수말벌, 말벌, 좀말벌, 꼬마장수말벌, 털보말벌 순으로 포획되었다. 두 유인제의 포획력 검정 결과, 신규 개발 유인제가 통계적으로 유의하게(P < 0.01) 등검은말벌 포획력이 높음을 보였다.
        34.
        2018.04 구독 인증기관·개인회원 무료
        벼메뚜기의 인공사료 개발을 위하여 일본의 Konno식 먹이를 대조구로 하고, 28개의 배합비율별 인공사료를 제작하여 급이시험을 하였다. 시험결과, Konno식 보다 6주 후 1마리당 체중은 22개 처리에서 높았고 우화성공율은 23개 처리에서 높았다. 폐사율은 부화입식 후 45일까지 Konno식 대비 24개 처리에서 높았다. 1마리당 체중, 우화성공율, 폐사율을 종합해 볼 때 탄수화물원으로는 옥수수 건조잎 분말 또는 통밀가루와 단백질원으로는 2~5%의 탈지대두분 또는 어분의 배합비율이 벼메뚜기의 인공사료로서 가능성이 높았다.
        35.
        2018.04 구독 인증기관·개인회원 무료
        Previously, a partial mitochondrial COI and CytB gene sequences have been used to infer genetic diversity and gene flow of the species. In this study, we additionally collected C. tripartitus from one previous and two new localities, sequenced the COI and CytB genes. Sequence divergence of current samples showed slightly lower values, but nearly equivalent to previous study. Haplotype diversity was still high and nucleotide diversity indicating that Seogwi-dong showed the highest estimates in both gene sequences. Gene flow among populations is high, but a significance difference was detected between Gulupdo and Anmado; and between Gulupdo and Seogwi-dong only in COI sequences (P < 0.05). Considering the high genetic diversity and gene flow in C. tripartitus populations, one of the major issues regarding conservation seems not to be the recovery of genetic diversity as has been suggested before.
        37.
        2017.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was aimed to evaluate the dose-response the effects of nano-encapsulated conjugated linoleic acids(CLAs) on in vitro ruminal fermentation profiles. A fistulated Holstein cow was used as a donor of rumen fluid. Nano-encapsulated CLAs(LF, 5% of nano-encapsulated CLA-FFA; HF, 10% of nano-encapsulated CLA-FFA; LT, 5% of nano-encapsulated CLA-TG; HT, 10% of nano-encapsulated CLA-TG) were added to the in vitro ruminal fermentation experiment. In the in vitro ruminal incubation test, the total gas production on incubation with nano-encapsulated CLAs was increased significantly according to the incubation time, compared with the control(p<0.05). The tVFA concentrations on addition of LF and HT were significantly higher than that of the control(p<0.05). Thus, nano-encapsulated CLAs might improve the ruminal fermentation characteristics without adverse effects on the incubation process. In addition, the population of Butyrivibrio fibrisolvens which is closely related to ruminal biohydrogenation was increased by adding HT, while decreased by adding LF at 12 h incubation. These results showed that nano-encapsulated CLA-FFA could be applied to enhance CLA levels in ruminants by maintaining the stability of CLA without causing adverse effects on ruminal fermentation profiles considering the optimal dosage.
        4,000원
        38.
        2017.04 구독 인증기관·개인회원 무료
        Despite of a substantial effort, the phylogeny of Lepidoptera still has unstable taxa and unresolved relationships particularly form Apoditrysia to Ditrysia (e.g. phylogenetic position and familial relationships of Gelechioidea, the monophylies of Tineoidea and Zygaenoidea and so on). We performed phylogenetic analysis using ~13,000-bp length of mitogenome sequences form 50 species (with seven species in two superfamilies form this study) representing 13 superfamilies to improve the lepidopteran phylogeny from Apoditrysia to Ditrysia. A close relationship of Gelechioidea to Obtectomera than to apoditrysian taxa was noteworthy, although the nodal support is very weak (ML, 23%; BI, BPP = 0.94). Monophyly of Zygaenoidea without Epipyropidae (Epipomponia nawai) was also noteworthy in spite of weak nodal support (ML, 64%; BI, 1.0). Scrutinized analysis is currently underway.
        39.
        2017.04 구독 인증기관·개인회원 무료
        We sequenced the complete mitochondrial genome (mitogenome) of Vespa velutina nigrithorax and V. ducalis (Hymenoptera: Vespidae). The genomes were 16,475-bp and 15,779-bp long and contained typical sets of genes. The V. velutina and V. ducalis A+T-rich region was 132-bp long and 166-bp long and was the shortest of all sequenced Vespoidea genomes. Start and stop codons in several Vespa species—including V. velutina and V. ducalis—were diversified, despite these species belonging to the same genus. In comparison with the ancestral mitogenomes, Vespa mitogenomes showed substantial gene rearrangement; however, we detected no gene rearrangement among Vespa species. We conducted phylogenetic reconstruction based on concatenated sequences of 13 PCGs and two rRNAs in available species of Vespoidea—22 species in six subfamilies in two families (Vespidae and Formicidae). The Bayesian inference and maximum likelihood (ML) methods revealed that each family formed strong monophyletic groups.
        40.
        2016.10 구독 인증기관·개인회원 무료
        Currently, only limited number of mitochondrial genomes (mitogenome) is available from Odonata. In order to extend current mitogenome data for comparative biology and phylogeny we sequenced complete mitogenomes of two endangered dragonfly species, Libellula angelina and Nannophya pygmaea (Ododana: Libellulidae). The whole genomes were 15,233 bp in L. angelina and 15,112 bp in N. pygmaea and included a typical set of genes (13 protein-coding genes, two rRNA genes, and 22 tRNA genes) and one major non-coding A+T-rich region. The arrangement of the genomes was identical to typical one found in insects. Phylogenetic reconstruction using concatenated sequences of 13 PCGs and two rRNAs of Odonata (17 species in eight families in three suborders) using both Bayesian Inference (BI) and Maximum Likelihood (ML) methods have shown a strong support for monophyletic Zygoptera (BI, BPP = 1 and ML, 100%). Currently, further scrutinized analysis is under progress.
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