• Korean Journal of Ichthyology
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• v.1 no.1_2
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• pp.35-41
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• 1989

An examination of the karyotypes, DNA values and nuclear sizes of three scups was undertaken as part of the study of cytogenetical evolution of order Perciformes. The chromosome number 2n=48 was the same in all three species but the numbers of chromosome arm were not identical. The distribution of genome size and nuclear volumes among species was continuous ranging from 1.287 pg and $20.78\;{\mu}m^3$ for Pagrus major down to 1.237 pg and $20.56\;{\mu}m^3$ for Acanthopagrus schlegeli. Above results indicate the possible role of pericentric inversions in the karyotypic evolution of these species.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.3C
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• pp.147-152
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• 2005

In this paper, we proposed a method for compressing the static video test patterns in high quality to test the picture quality in DTV. In our method, we use the fact that the generated bits and average quantization value have almost identical distribution characteristics per each GOP and we propose a new target bit allocation method suitable for compressing the static test pattern while the target bit allocation method in MPEG-2 TM5 is suitable for the moving picture. The proposed target bit allocation method is to maintain the high quality video continuously by using the normalized complexities which are updated or maintained by means of picture qualities at each GOP. Experiment result showed that the test pattern stream encoded by MPEG-2 software with the proposed algorithm had a stable bit rate and good video quality during the decoding process.

• Atmosphere
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• v.15 no.2
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• pp.91-99
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• 2005

This study compares the summer monsoon circulations during a heavy rainfall period over the Korean peninsular from 11 to 18 July 2004, simulated by three widely used regional models; WRF, MM5, and RSM. An identical model setup is carried out for all the experiments, except for the physical option differences in the RSM. The three models with a nominal resolution of about 50 km over Korea are nested by NCEP-DOE reanalysis data. Another RSM experiment with the same cumulus parameterization scheme as in the WRF and MM5 is designed to investigate the importance of the representation of subgrid-scale parameterized convection in reproducing monsoonal circulations in East Asia. All thee models are found to be capable of reproducing the general distribution of monsoonal precipitation, extending northeastward from south China across the Korean peninsula, to northern Japan. The results from the WRF and MM5 are similar in terms of accumulated precipitation, but a slightly better performance in the WRF than in the MM5. The RSM improves the bias for precipitation as compared to those from the WRF and MM5, but the pattern correlation is degraded due to overestimation of precipitation in northern China. In the comparison of simulated synoptic scale features, the RSM is found to reproduce the large-scale features well compared to the results from the MM5 and WRF. On the other hand, the simulated precipitation from the RSM with the convection scheme used in the MM5 and WRF is closer to that from the WRF and MM5 simulations, indicating the significant dependency of simulated precipitation in East Asia on the cumulus parameterization scheme.

• The Korean Journal of Applied Statistics
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• v.22 no.5
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• pp.911-921
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• 2009

Receiver Operating Characteristic(ROC) and Cumulative Accuracy Profile(CAP) curves are two methods used to assess the discriminatory power of different credit-rating approaches. The points of optimal classification accuracy on an ROC curve and of maximal profit on a CAP curve can be found by using iso-performance tangent lines, which are based on the standard notion of accuracy. In this paper, we offer an alternative accuracy measure called the true rate. Using this rate, one can obtain alternative optimal threshold points on both ROC and CAP curves. For most real populations of borrowers, the number of the defaults is much less than that of the non-defaults, and in such cases the true rate may be more efficient than the accuracy rate in terms of cost functions. Moreover, it is shown that both alternative scores of optimal classification accuracy and maximal profit are the identical, and this single score coincides with the score corresponding to Kolmogorov-Smirnov statistic used to test the homogeneous distribution functions of the defaults and non-defaults.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.662-667
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• 2007

The thermal performance comparisons of the dish solar collector system are numerically investigated with mirror arrays and receiver shapes. In order to compare the performances of the dish solar collector systems, six different mirror arrays and four different receiver shapes are considered and the radiative heat flux distribution on the inside of the receiver is analyzed. A parabolic-shaped perfect mirror of which diameter is 1.5 m is considered as a reference of the mirror arrays. Five different mirror arrays of twelve identical parabolic -shaped mirror facets of which diameter are 0.4 m are proposed in this study. Their reflecting areas, which are 1.5 $m^2$, are the same. Four different receiver shapes are a dome, a conical, a cylindrical and a unicorn type. The solar irradiation reflected by mirrors is traced using the Monte-Carlo method. In addition, the radiative properties of the mirror surface can vary the thermal performance of the dish solar collector system so that the effects of the surface reflectivity and the surface absorptivity are considered. Based on the calculation, the design information of dish solar collector system for producing the electric power can be obtained. The results show that the dome type has the best performance in receiver shapes and the 2AND4INLINE has the best performance in mirror arrays except the perfect mirror.

• Journal of Microbiology and Biotechnology
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• v.27 no.1
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• pp.101-111
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• 2017

The task of improving a fungal strain is highly time-consuming due to the requirement of a large number of flasks in order to obtain a library with enough diversity. In addition, fermentations (particularly those for fungal cells) are typically performed in high-volume (100-250 ml) shake-flasks. In this study, for large and rapid screening of itaconic acid (IA) high-yielding mutants of Aspergillus terreus, a miniaturized culture method was developed using 12-well and 24-well microtiter plates (MTPs, working volume = 1-2 ml). These miniaturized MTP fermentations were successful, only when highly filamentous forms were induced in the growth cultures. Under these conditions, loose-pelleted morphologies of optimum sizes (less than 0.5 mm in diameter) were casually induced in the MTP production cultures, which turned out to be the prerequisite for the active IA biosynthesis by the mutated strains in the miniaturized fermentations. Another crucial factor for successful MTP fermentation was to supply an optimal amount of dissolved oxygen into the fermentation broth through increasing the agitation speed (240 rpm) and reducing the working volume (1 ml) of each 24-well microtiter plate. Notably, almost identical fermentation physiologies resulted in the 250 ml shake-flasks, as well as in the 12-well and 24-well MTP cultures conducted under the respective optimum conditions, as expressed in terms of the distribution of IA productivity of each mutant. These results reveal that MTP cultures could be considered as viable alternatives for the labor-intensive shake-flask fermentations even for filamentous fungal cells, leading to the rapid development of IA high-yield mutant strains.

• Journal of the Korean Society for information Management
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• v.30 no.2
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• pp.297-315
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• 2013

This study aims to analyze and evaluate term suggestion services of major search portals, Naver and Google Korea. In particular, this study evaluated relevance and currency of related search terms provided, and analyzed characteristics such as number and distribution of terms, and queries that did not produce terms. This study also analyzed types of terms in terms of the relationship between queries and terms, and investigated types and characteristics of harmful terms and terms with grammatical errors. Finally, Korean queries and English queries, and popular queries and academic queries were compared in terms of the amount and relevance of search terms provided. The results of this study show that the relevance and currency of Naver's related search terms are somewhat higher than those of Google. Both Naver and Google tend to add terms to or delete terms from original queries, and provide identical search terms or synonym terms rather than providing entirely new search terms. The results of this study can be implemented to the portal's effective development of term suggestion services.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.2
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• pp.195-200
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• 1997

Water transport in highly-permeable membranes is facilitated by some specialized pathways, which are called aquaporins (AQP). AQP1 (AQP-CHIP) is the first recognized aquaporin identified from red cells and renal proximal tubules. Up until now 4 other aquaporin homologs have been reported. Each aquaporin has its unique tissue distribution and regulatory mechanims. To elucidate molecular mechanisms for their transcription regulation and tissue-specific expression isolation of aquaporin genes is required. To clone promoters of the AQP family mouse genomic library was screened by the 1st exon-specific probe of AQP4, and 5 different plaques were positively hybridized. Phage DNAs were purified and characterized by restriction mapping and sequencing. One of them is the mouse AQP-CD gene. The gene was consisted of 4 exons and the exon-intron boundaries of mouse AQP-CD gene were identified at identical positions in other related genes. The 5'-flanking region of AQP-CD gene contains one classic TATA box, a GATA consensus sequence, an E-box and a cyclic AMP-responsive element. The cloning of the mouse AQP-CD gene, of which product is expressed in the collecting duct and is responsible for antidiuresis by vasopressin, will contribute to understand the molecular mechanisms of tissue-specific expression and regulation of AQP-CD gene under various conditions.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.704-715
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• 2006

Oil spill was found in 1999 from a diesel storage facility located near the top of Baekun Mountain in Uiwang City. Application of bioremediation techniques was very relevant in removing oil spills in this site, because the geological condition was not amenable for other onsite remediation techniques. For efficient bioremediation, bacterial communities of the contaminated site and the uncontaminated control site were compared using both molecular and cultivation techniques. Soil bacterial populations were observed to be stimulated to grow in the soils contaminated with diesel hydrocarbon, whereas fungal and actinomycetes populations were decreased by diesel contamination. Most of the dieseldegrading bacteria isolated from contaminated forest soils were strains of Pseudomonas, Ralstonia, and Rhodococcus species. Denaturing gradient gel electrophoresis (DGGE) analysis revealed that the profiles were different among the three contaminated sites, whereas those of the control sites were identical to each other. Analysis of 16S rDNA sequences of dominant isolates and clones showed that the bacterial community was less diverse in the oil-contaminated site than at the control site. Sequence analysis of the alkane hydroxylase genes cloned from soil microbial DNAs indicated that their diversity and distribution were different between the contaminated site and the control site. The results indicated that diesel contamination exerted a strong selection on the indigenous microbial community in the contaminated site, leading to predominance of well-adapted microorganisms in concurrence with decrease of microbial diversity.

• Journal of the Microelectronics and Packaging Society
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• v.18 no.4
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• pp.27-32
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• 2011

Tin nanoparticles were synthesized at room temperature by a compulsive reduction reaction using tin(II) acetate and tin(II) chloride precursors. When an identical amount (0.015 g) of polyvinyl pyrrolidone (PVP) was added, it was concluded that the probability of abnormally big particles forming increased with an increase in PVP molecular weight, resulting in the wide distribution of Sn nanoparticles. Differential scanning calorimetry measurements were carried out using diethylene glycol solution containing synthesized tin nanoparticles. When the population of specific particles with sizes below 35 nm was adequate, the melting point depression peaks of tin nanoparticles corresponding to the specific size were observed besides an evaporation endothermic peak of DEG during the first heating. Because DEG was evaporated and tin nanoparticles in contact became molten and coarsened during the first heating, a melting peak of bulk tin was only observed at $232^{\circ}C$ during the second heating.