• The Journal of Fisheries Business Administration
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• v.43 no.2
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• pp.79-94
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• 2012

The purpose of this study is to investigate the production efficiencies of the Korean aquaculture fishery with respect to species and methods using a Data Envelopment Analysis. The study extracted the 8 fishes in each of the sea cage culture, aquarium basin, and enclosed aquaculture for the analytical purposes. First, the study estimated the technical, pure technical, and scale efficiencies of the total of 24 aquaculture fishes based on the traditional DEA under the assumptions of both CRS and VRS. 2 fishes were identified as the efficient DMUs under the CCR-model, and 6 fishes under the BCC-model. Second, we tested to see if there was any difference in production efficiencies regarding those three different methods of aquaculture. we could not find any evidence of the differences in efficiency using a rank sum test based on the traditional DEA. However, we could do find that the pure technical efficiency in the sea cage culture was lower than others at 1% level of significance and the pure technical efficiency in enclosed aquaculture was also lower than others at 5% level of significance using Bilateral-DEA, which could explicitly consider the heterogeneity in the 3 production methods of aquaculture. Finally, the study obtained the 95% confidence intervals of the efficiency scores for the 24 fishes under our study using the smoothed bootstraping method in the process of the re-sampling in cooperation with both a kernel density estimation and a reflection method. At the same time, we could estimate the bias-corrected efficiency scores while the traditionally estimated efficiency scores suffered from the biases in the process of solving a linear programming with the deterministic nature of a production frontier. And hence, we could distinguish the differences in production efficiencies of the 8 fishes with respect to those 3 methods of aquaculture.

• ALGAE
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• v.30 no.4
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• pp.265-274
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• 2015

Thorea indica sp. nov. is described from the Sai River, Uttar Pradesh, India (26°39′00.7″ N, 80°47′38.3″ E). Its classification is based on molecular sequences of the plastid-encoded RuBisCO large-subunit gene, rbcL and the barcode region of the mitochondrial encoded cytochrome c oxidase subunit 1, cox1, and morphological data. The sequence analyses confirm a new species of Thorea. The cox1 barcode sequence had 90.4-90.8% identity with Thorea sp. from Australia and Thorea hispida from Hawaii and China. Based on rbcL sequences the Indian specimen was positioned in a major clade with high support (>95 bootstrap and 0.95 posterior probability) containing two other species: T. okadae from Japan and T. hispida from the continental USA, Hawaii, the UK, and China. The divergences among these sequences were T. indica vs. T. okadae (2.8%) and T. indica vs. T. hispida (2.9-3.4%). The comparison of morphological characters of Thorea from India was not conclusive due to the inadequate descriptions in previous reports: most specimens reported as T. hispida fit within the circumscription of T. indica as described here. The previous report of T. siamensis from the Sai River is incorrect and the specimens fit within our description of T. indica. Thorea indica and T. okadae can be distinguished by minor morphometric characters and sexuality (dioecious vs. monoecious).

• Parasites, Hosts and Diseases
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• v.54 no.4
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• pp.503-507
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• 2016

The genus Spirometra belongs to the family Diphyllobothriidae and order Pseudophyllidea, and includes intestinal parasites of cats and dogs. In this study, a plerocercoid labeled as Spirometra mansonoides from the USA was examined for species identification and phylogenetic analysis using 2 complete mitochondrial genes, cytochrome c oxidase I (cox1) and NADH dehydrogenase subunit 3 (nad3). The cox1 sequences (1,566 bp) of the plerocercoid specimen (USA) showed 99.2% similarity to the reference sequences of the plerocercoid of Korean Spirometra decipiens (GenBank no. KJ599679), and 99.1% similarity in regard to nad3 (346 bp). Phylogenetic tree topologies generated using 4 analytical methods were identical and showed high confidence levels with bootstrap values of 1.00, 100%, 100%, and 100% for Bayesian inference (BI), maximum-likelihood (ML), neighbor-joining (NJ), and maximum parsimony (MP) methods, respectively. Representatives of Diphyllobothrium and Spirometra species formed a monophyletic group, and the sister-genera status between these species was well supported. Trapezoic proglottids in the posterior 1/5 region of an adult worm obtained from an experimentally infected cat were morphologically examined. The outer uterine loop of the uterus coiling characteristically consisted of 2 complete turns. The results clearly indicated that the examined Spirometra specimen from the USA matched to S. decipiens very well, and indicated possible presence of the life cycle of this species in this region.

• The Plant Pathology Journal
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• v.16 no.1
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• pp.29-35
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• 2000

The internal transcribed spacer regions (ITS I, 5.8S and ITS II) of the ribosomal DNAs were amplified from Korean isolates of Phytophthora spp. and sequenced to characterize them. Sequences from 33 isolates previously identified as P. boehmeriae, P. cactprum, P. cambivora, P. capsici, P. cinnamomi, P. erythroseptica, P. infestans, P. megasperma, P. melonis, P. nicotianae, P. palmivora and P. sojae were compared with published sequences, and a phylogenetic tree was produced. All isolates belonging to 10 species, P. cactorum, P. cambivora, P. capsici, P. cinnamomi P. citricola, P. infestans, P. nicotianae, P. palmivora and P. sojae were clearly clustered into published isolates of each species above 97% bootstrap value. Cucurbits isolates of Phytophthora previously identified as either P. melonis or P. drechsleri showed distinct evolutionary lineages from the P. megasperma was closely related to isolates of P. cryptogea-P. drechsleri showed distinct evolutionary lineages from the P. cryptogea-P. drechsleri complex group, indicating that P. melonis is a valid species. A Korean isolate of P. megasperma was closely related to isolates of P. erythroseptica showed distant genetic relationship with published isolates of P. erythroseptica (CBS 956.87). It is probable that the two Korean isolates could be genetically different from foreign isolates or misidentified. A grouping of species according to ITS sequence divergence matched, to some degree, the broad classification based on type of papilla. However, a separation of semi-papillate species and papillate species was not wvident in this study.

• Korean Journal of Plant Taxonomy
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• v.44 no.4
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• pp.250-256
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• 2014

This study was carried out to understand the genetic relationship of three Aloe spp. cultivated in Korea, A. saponaria, A. vera and A. arborescens and a new variant in Korea based on three plastid (matK, trnL-F, rbcL) and one nuclear (ITS regions) DNA barcode markers. A total of 2,420 bp sequence was amplified. Two indels were detected in the trnL region, and also several species specific nucleotide loci were detected in all 29 parsimonious informative sites, and 148 variable sites were detected among four taxa studied while 170 variable and 75 parsimonious sites were detected when other Aloe spp. in worldwide were used. An UPGMA phenogram with 10,000 bootstrap replication showed that the new variant was closest to A. vera. The variant was not morphologically and genetically concurrent with any reported species so far. The clustering of Aloe species were broadly in agreement with previously reported results.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.6
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• pp.760-770
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• 2016

A 12-bit 750 kS/s Dual-Sampling Successive Approximation Register Analog-to-Digital Converter (SAR ADC) technique with reduced Capacitive DAC (CDAC) is presented in this paper. By adopting the Adaptive Power Control (APC) technique for the two-stage latched type comparator and using bootstrap switch, power consumption can be reduced and overall system efficiency can be optimized. Bootstrapped switches also are used to enhance the sampling linearity at a high input frequency. The proposed SAR ADC reduces the average switching energy compared with conventional SAR ADC by adopting reduced the Most Significant Bit (MSB) cycling step with Dual-Sampling of the analog signal. This technique holds the signal at both comparator input asymmetrically in sample mode. Therefore, the MSB can be calculated without consuming any switching energy. The prototype SAR ADC was implemented in $0.18-{\mu}m$ CMOS technology and occupies $0.728mm^2$. The measurement results show the proposed ADC achieves an Effective Number-of-Bits (ENOB) of 10.73 at a sampling frequency of 750 kS/s and clock frequency of 25 MHz. It consumes only 0.13 mW from a 5.0-V supply and achieves the INL and DNL of +2.78/-2.45 LSB and +0.36/-0.73 LSB respectively, SINAD of 66.35 dB, and a Figures-of-Merit (FoM) of a 102 fJ/conversion-step.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.6
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• pp.367-373
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• 2007

We assessed the stock of the southern bluefin tuna (SBT, Thunnus maccoyii) by applying the MULTIFAN-CL model. The model is spatially disaggregated, with the population and fisheries stratified into a number of regions within the overall stock range. Catch, effort, length-frequency, and tagging data from 1965 to 2003 were stratified by three regions and four quarters (Jan-Mar, Apr-Jun, Jul-Sept and Oct-Dec). These data were used to estimate the instantaneous fishing mortality (F), biomass, spawning biomass, recruitment, and so on. The Commission for the Conservation of Southern Bluefin Tuna (CCSBT) used only Japanese data and did not consider migration for the SBT stock assessment. By contrast, we used Japanese, Australian, New Zealand, Taiwanese, and Korean data, and considered migration. As a result, the estimated annual average F of all age classes was 0.073/yr and the F of age class 6-10 was the highest. The results also showed that the biomass and recruitment of SBT had declined significantly after 1965. Compared with the CCSBT results, the estimated spawning biomass in this study was lower and more uncertain. However, we will conduct a sensitivity analysis to get more accurate biological parameters and results. In addition, we need to use the bootstrap resampling method to quantify the uncertainty.

• The Korean Journal of Applied Statistics
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• v.30 no.6
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• pp.877-888
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• 2017

Spectral analysis is used to determine the frequency of time series data. We first determine the frequency of the series through the power spectrum or the periodogram and then calculate the period of a cycle that may exist in a time series. Estimating the frequency using a Bayesian technique has been developed and proven to be useful; however, the Bayesian estimator for the frequency cannot be analytically solved through mathematical equations and may be handled numerically or computationally. In this paper, we make an inference on the Bayesian frequency through both resampling a parameter by Markov chain Monte Carlo (MCMC) methods and resampling data by bootstrap methods for a time series. We take the Korean real estate price index as an example for Bayesian frequency estimation. We have found a difference in the periods between the sale price index and the long term rental price index, but the difference is not statistically significant.

• The Plant Pathology Journal
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• v.29 no.1
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• pp.52-58
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• 2013

Fusarium head blight (FHB) caused by the filamentous fungus Fusarium graminearum is one of the most severe diseases threatening the production of small grains. Infected grains are often contaminated with mycotoxins such as zearalenone and trichothecences. During survey of contamination by FHB in rice grains, we found a bacterial isolate, designated as BN1, antagonistic to F. graminearum. The strain BN1 had branching vegetative hyphae and spores, and its aerial hyphae often had long, straight filaments bearing spores. The 16S rRNA gene of BN1 had 100% sequence identity with those found in several Streptomyces species. Phylogenetic analysis of ITS regions showed that BN1 grouped with S. sampsonii with 77% bootstrap value, suggesting that BN1 was not a known Streptomyces species. In addition, the efficacy of the BN1 strain against F. graminearum strains was tested both in vitro and in vivo. Wheat seedling length was significantly decreased by F. graminearum infection. However, this effect was mitigated when wheat seeds were treated with BN1 spore suspension prior to F. graminearum infection. BN1 also significantly decreased FHB severity when it was sprayed onto wheat heads, whereas BN1 was not effective when wheat heads were point inoculated. These results suggest that spraying of BN1 spores onto wheat heads during the wheat flowering season can be efficient for plant protection. Mechanistic studies on the antagonistic effect of BN1 against F. graminearum remain to be analyzed.

• Journal of Wetlands Research
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• v.20 no.2
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• pp.116-123
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• 2018

The objective of this study was to examine effects of stand age on soil $CO_2$ efflux in plantation Pinus koraiensis, and to elucidate what extent plant (fine) root and soil microbial biomass contribute to the whole soil $CO_2$ efflux. In three age classes (20-yr-old. 40-yr-old, 70-yr-old) of plantation Pinus koraiensis, in-situ soil respiration, plant fine root biomass and soil microbial biomass were measured from April to November in 2004. Regardless of stand age, soil temperature and soil $CO_2$ efflux increased until July then slowly decreased. Soil respiration was higher in 70-yr-old stand than in 20- and 40-yr stands. Fine root biomass and soil microbial biomass was also higher in 70-yr-old stand. Root exclusion decreased soil respiration in 40-yr stand, but not in 70-yr stand. Soil microbial biomass was higher in 70-yr stand, but there was no monthly variation between July and November. The results suggest that soil respiration may increase as plant stand ages and microbial contribution could play more roles in older stands.