• Structural Engineering and Mechanics
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• 제48권6호
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• pp.879-914
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• 2013

In part I of the article, formulation and characteristics of the several well-known structural geometrical nonlinear solution techniques were studied. In the present paper, the efficiencies and capabilities of residual load minimization, normal plane, updated normal plane, cylindrical arc length, work control, residual displacement minimization, generalized displacement control and modified normal flow will be evaluated. To achieve this goal, a comprehensive comparison of these solution methods will be performed. Due to limit page of the article, only the findings of 17 numerical problems, including 2-D and 3-D trusses, 2-D and 3-D frames, and shells, will be presented. Performance of the solution strategies will be considered by doing more than 12500 nonlinear analyses, and conclusions will be drawn based on the outcomes. Most of the mentioned structures have complex nonlinear behavior, including load limit and snap-back points. In this investigation, criteria like number of diverged and complete analyses, the ability of passing load limit and snap-back points, the total number of steps and analysis iterations, the analysis running time and divergence points will be examined. Numerical properties of each problem, like, maximum allowed iteration, divergence tolerance, maximum and minimum size of the load factor, load increment changes and the target point will be selected in such a way that comparison result to be highly reliable. Following this, capabilities and deficiencies of each solution technique will be surveyed in comparison with the other ones, and superior solution schemes will be introduced.

• Parasites, Hosts and Diseases
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• 제53권3호
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• pp.345-348
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• 2015

Toxoplasma gondii is a eukaryotic parasite of the phylum Apicomplexa, which infects all warm-blood animals, including humans. In the present study, we examined sequence variation in dense granule 20 (GRA20) genes among T. gondii isolates collected from different hosts and geographical regions worldwide. The complete GRA20 genes were amplified from 16 T. gondii isolates using PCR, sequence were analyzed, and phylogenetic reconstruction was analyzed by maximum parsimony (MP) and maximum likelihood (ML) methods. The results showed that the complete GRA20 gene sequence was 1,586 bp in length among all the isolates used in this study, and the sequence variations in nucleotides were 0-7.9% among all strains. However, removing the type III strains (CTG, VEG), the sequence variations became very low, only 0-0.7%. These results indicated that the GRA20 sequence in type III was more divergence. Phylogenetic analysis of GRA20 sequences using MP and ML methods can differentiate 2 major clonal lineage types (type I and type III) into their respective clusters, indicating the GRA20 gene may represent a novel genetic marker for intraspecific phylogenetic analyses of T. gondii.

• International Journal of Industrial Entomology and Biomaterials
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• 제44권2호
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• pp.65-71
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• 2022

The wild silkmoth Antheraea yamamai Guérin-Méneville, 1861 (Lepidoptera: Saturniidae) is an important producer of silk that is superior to the silk produced by traditional domesticated silkworm. In this study, we sequenced the complete mitochondrial genome (mitogenome) of An. yamamai collected from Jeju Island, which is the southernmost island approximately 100 km offshore southward from the Korean Peninsula. Determining this sequence will be necessary for tracing the biogeographic history of the species and developing molecular markers for identifying the origin of commercial products. Comparison of the sequence divergence among two available and the current mitogenomes revealed a low but substantial number of substitutions, totaling 23 nucleotides in the whole genome. CytB and ND5 showed the highest variability with five and four variations, respectively, suggesting that these regions will be prior regions to target for subsequent biogeographic and diagnosis study. Phylogenetic reconstruction based on all available sequences of Saturniidae showed that An. yamamai is a sister to the congeneric species An. pernyi, corroborating that Antheraea is a highly supported monophyletic group. The tribe Saturniini was clearly non-monophyletic and interrupted by Attacini and Bunaeini.

• Animal cells and systems
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• 제16권5호
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• pp.408-414
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• 2012

To reexamine taxonomic status of endemic Mogera wogura coreana from Korea, we first obtained partial 12S rRNA sequences (893 bp) and complete cytochrome b gene sequences (1140 bp) of this subspecies, and these sequences and partial cytochrome b sequences (402 bp) were compared to the corresponding haplotypes of M. wogura from East Asia, obtained from GenBank. The one of three 12S rRNA haplotypes in M. w. coreana was identical to one 12S rRNA haplotype of M. w. robusta from East Asia: 10 complete and 13 partial cytochrome b haplotypes of M. w. coreana formed a single clade with one complete and four partial cytochrome b haplotypes of M. w. robusta, respectively. We considered that M. w. coreana from Korea is an endemic subspecies with only morphological differences, although it is necessary to reexamine the subspecies status of M. w. coreana. Additionally, in the 12S rRNA and complete cytochrome b sequences, M. wogura from Japan was distinct from the two continental subspecies of M. w. coreana and M. w. robusta with average distances of 1.76 and 5.65%, respectively; insular M. wogura, with within-group distances of 2.09 and 4.38%, respectively, was also genetically more divergent than the mainland M. wogura, with within-group distances of 0.08 and 0.57%, respectively. Thus, we considered that insular M. wogura of Japan dispersed into neighboring East Asian continent, which is opposite to the traditional hypothesis on the origin of Japanese M. wogura.

• Journal of Ecology and Environment
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• 제36권4호
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• pp.449-463
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• 2013

DNA barcoding is becoming a widely applied tool to accurately discriminate red algae. We tested the effectiveness of DNA barcoding for identification and discovery of Champia species in Korea and clarified the phylogenetic relationships using the plastid rbcL gene. As results, we described four species of Champia such as C. inkyua sp. nov., C. recta Noda, C. bifida Okamura, and C. expansa Yendo. A new species, C. inkyua, is characterized by entangled thallus, terete and irregular branches, hooked apices, and longitudinal filaments running throughout the frond periphery only. Longitudinal filaments were composed of a complete cell with two half cells between diaphragms in the cavity. C. recta and C. bifida were reinstated with previously used names of C. parvula and C. compressa, respectively. C. recta is the first recorded species from Korea and is characterized by an erect thallus, terete and irregular branches, and straight apices. C. bifida is characterized by compressed thallus, pinnate or alternate branches, and bifid apices. C. expansa is characterized by flabellate thallus and dichotomous branches. Molecular analyses of COI and rbcL genes revealed sufficient sequence divergence to warrant species recognition in the genus Champia.

• Parasites, Hosts and Diseases
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• 제54권3호
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• pp.369-373
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• 2016

The 2 species of the genus Anoplocephala (Anoplocephalidae), A. perfoliata and A. magna, are among the most important equine cestode parasites. However, there is little information about their differences at the molecular level. The present study revealed that the mitochondrial (mt) genome of A. magna was 13,759 bp in size and 700 bp shorter than that of A. perfoliata. The 2 species includes 2 rRNA, 22 tRNA, and 12 protein-coding genes each. The size of each of the 36 genes was the same as that of A. perfoliata, except for cox1, rrnL, trnC, trnS2(UCN), trnG, trnH, trnQ, and trnP. In the full mitochondrial genome, the sequence similarity was 87.1%. The divergence in the nucleotide and amino acid sequences of individual protein-coding genes ranged from 11.1% to 16% and 6.8% to 16.4%, respectively. The 2 non-coding regions of the mt genome of A. magna were 199 bp and 271 bp in length, while the equivalent regions in A. perfoliata were 875 bp and 276 bp, respectively. The results of this study support the proposal that A. magna and A. perfoliata are separate species, consistent with previous morphological analyses.

• 한국환경과학회지
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• 제10권5호
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• pp.329-336
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• 2001

Characgcteristics of nocturnal boundary layer(NBL) were analyzed by the upper-air observations data using with the airsonde and pilot balloons from 1994 to 1999 in Kyungpook province. The automate weather boundary layer can become stably stratified when the surface is cooler than the air. Stable nocturnal boundary layer height were estimated from the top of surface stable layer where the vertical gradient of temperature and mixing ratio tend to zero or negative. The depth of the stable nocturnal boundary layer depended largely on the thermal effect rather than the wind effect at nighttime. The NBL was more developed on the land than on the coastal region. The stability index (bulk Richardson number) showed that the NBL was stable when the wind was weak and the vertical gradient of the temperature was strong. The heat budget in the NBL was studied by considering the effect of the radiative and the cooled by both the longwave radiative flux and the divergence of the heat flux, while NBL under the cloudy sky the longwave radiative flux played a role of the warming. It was noted that the heat was not conserved in both cases. To complete the heat budget in the NBL the warming/cooling by advection and subsidence must be considered.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.816-823
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• 2007

Electric car tract plays the role of supply high electric power to the electric car from the substation by using Pantograph of the electric car. It is always exposed to the external atmosphere, which results in quite substantial fluctuations in current and voltage during operation of electric car. This generates possibility of occurrence of accident at all times. Since range of wiring metallic globe installed on the catenary cannot achieve complete electrical contact, accidents are occurring due to circulating current caused by arc caused by incomplete contact due to occurrence of hairline fracture of Pantograph due to pressure or vibration of wiring. Furthermore, rapid increase in the operational current due to increase in the operational frequency of the electric car is causing erosion and short circuit of the metallic globe at the contact points. This study on arc is generated as current transmitted out of the substation courses through power line or wiring metallic globe other than the main circuit as the current is being collected at the electric car through feeder and feeder divergence device. Accordingly, since heat generated by the arc becomes the cause for generation of circulating current due to melting of metal or softening of metal due to increase in temperature accompanying increase in contact resistance, this research shall describe causes and measures against occurrence of circulation current.

• Parasites, Hosts and Diseases
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• 제56권6호
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• pp.583-588
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• 2018

Although widely studied, the natural diversity of the hard tick is not well known. In this study, we collected 194 sequences from 67 species, covering 7 genera of hard tick. The 5' region of the mitochondrial cytochrome c oxidase subunit 1 region (586 bp) has been used to investigate intra- and inter-species variation and the phylogenetic tree of neighbor joining method has been used for assessment. As a result, by comparing the K2P-distance of intra- and interspecies, 30 samples (15.2%) shown that interspecies distance was larger than the minimum interspecfic distance. From the phylogenetic analysis, 86.8% (49) of the species were identified correctly at the genus level. On deeper analysis on these species suggested the possibility of presence cryptic species. Therefore, further work is required to delineate species boundaries and to develop a more complete understanding of hard tick diversity over larger scale.

• Animal Systematics, Evolution and Diversity
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• 제28권2호
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• pp.133-136
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• 2012

The objective of this study was to determine the degree of mitochondrial DNA (mtDNA) divergence between two subspecies of $Mustela$ $sibirica$ from Korea ($M.$ $s.$ $coreanus$ on the Korean Peninsula and ($M.$ $s.$ $quelpartis$ on Jeju Island) and to examine the taxonomic status of ($M.$ $s.$ $quelpartis$. Thus, we obtained complete sequences of mtDNA cytochrome $b$ gene (1,140 bp) from the two subspecies, and these sequences were compared to a corresponding haplotype of ($M.$ $s.$ $coreanus$, downloaded from GenBank. From this analysis, it was observed that the sequences from monogenic ($M.$ $s.$ $quelpartis$ on Jeju Island were identical to the sequences of four ($M.$ $s.$ $coreanus$from four locations across the Korean Peninsula, and that the two subspecies formed a single clade; the average nucleotide distance between the two subspecies was 0.26% (range, 0.00 to 0.53%). We found that the subspecies $quelpartis$ is not genetically distinct from the subspecies $coreanus$, and that this cytochrome $b$ sequencing result does not support the current classification, distinguishing these two subspecies by pelage color. Further systematic analyses using morphometric characters and other DNA markers are necessary to confirm the taxonomic status of ($M.$ $s.$ $quelpartis$.