• Journal of the Korean Chemical Society
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• v.35 no.4
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• pp.308-315
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• 1991

The structure and thermodynamic properties of body centered cubic structure of simple Coulombic liquids are computed from the perturbation theory for one-component plasma. A comparison of perturbation theory (PT) and Monte Carlo (MC) simulation shows excellent agreement. The hardsphere perturbation theory is applicable to a long-range attractive system, such as the one-component plasma. A comparison of the radial distribution function (g(r)) and the structure factor (S(q)) for PT data and MC data shows agreement. Thus the perturbation theory is an applicable method to explain the structure and thermodynamic properties of Coulomb liquids.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.5
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• pp.463-469
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• 2015

In this study, we synthesized graphene oxide and developed novel spin-spray coating technology. The graphene oxide thin film was uniformly coated on amine-functionalized glass surfaces using spin-spray coating technology. We also stacked up to four layers of graphene oxide on glass substrates in a uniform manner. From the results, we infer that this spin-spray coating of graphene oxide thin film could be a powerful tool for various electronic display coating applications.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.7
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• pp.939-948
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• 2019

Objective: Extension and Agouti loci play a key role for proportions of eumelanin and pheomelanin in determining coat color in several species, including goat. Mongolian goats exhibit diverse types of coat color phenotypes. In this study, investigation of the melanocortin 1 receptor (MC1R) coding region in different coat colors in Mongolian goats was performed to ascertain the presence of the extension allele. Methods: A total of 105 goat samples representing three goat breeds were collected for this study from middle Mongolia. A 938 base pair (bp) long coding region of the MC1R gene was sequenced for three different breeds with different coat colors (Gobi Gurwan Saikhan: complete black, Zalaa Jinstiin Tsagaan: complete white, Mongolian native goat: admixture of different of coat colors). The genotypes of these goats were obtained from analyzing and comparing the sequencing results. Results: A total of seven haplotypes defined by five substitution were identified. The five single nucleotide polymorphisms included two synonymous mutations (c.183C>T and c.489G>A) and three missense (non-synonymous) mutations (c.676A>G, c.748T>G, and c.770T>A). Comparison of genotypes frequencies of two common missense mutions using chi-sqaure ($x^2$) test revealed significant differences between coat color groups (p<0.001). A logistic regression analysis additionally suggested highly significant association between genotypes and variation of black versus white uniform combination. Alternatively, most investigated goats (60.4%) belonged to H2 (TGAGT) haplotype. Conclusion: According to the findings obtained in this study on the investigated coat colors, mutations in MC1R gene may have the crucial role for determining eumelanin and pheomelanin phenotypes. Due to the complication of coat color phenotype, more detailed investigation needed.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.9
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• pp.1229-1238
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• 2016

This study was conducted to determine the relationships of five intragenic single nucleotide polymorphism (SNP) markers (protein kinase adenosine monophosphate-activated ${\gamma}3$ subunit [PRKAG3], fatty acid synthase [FASN], calpastatin [CAST], high mobility group AT-hook 1 [HMGA1], and melanocortin-4 receptor [MC4R]) and meat quality traits of Duroc breeding stocks in Korea. A total of 200 purebred Duroc gilts from 8 sires and 40 dams at 4 pig breeding farms from 2010 to 2011 reaching market weight (110 kg) were slaughtered and their carcasses were chilled overnight. Longissimus dorsi muscles were removed from the carcass after 24 h of slaughter and used to determine pork properties including carcass weight, backfat thickness, moisture, intramuscular fat, $pH_{24h}$, shear force, redness, texture, and fatty acid composition. The PRKAG3, FASN, CAST, and MC4R gene SNPs were significantly associated with the meat quality traits (p<0.003). The meats of PRKAG3 (A 0.024/G 0.976) AA genotype had higher pH, redness and texture than those from PRKAG3 GG genotype. Meats of FASN (C 0.301/A 0.699) AA genotype had higher backfat thickness, texture, stearic acid, oleic acid and polyunsaturated fatty acid than FASN CC genotype. While the carcasses of CAST (A 0.373/G 0.627) AA genotype had thicker backfat, and lower shear force, palmitoleic acid and oleic acid content, they had higher stearic acid content than those from the CAST GG genotype. The MC4R (G 0.208/A 0.792) AA genotype were involved in increasing backfat thickness, carcass weight, moisture and saturated fatty acid content, and decreasing unsaturated fatty acid content in Duroc meat. These results indicated that the five SNP markers tested can be a help to select Duroc breed to improve carcass and meat quality properties in crossbred pigs.

• Korean Journal of Agricultural Science
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• v.19 no.2
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• pp.179-186
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• 1992

This experiment was carried out to study the drying characteristics of model foods containing moisture, protein and starch on different concentration of additives such as sodium chloride and sucrose. Textural properties of model foods were measured by using UTM(instron). The results obtained are summaried as follows: As starch content and solute concentration of model foods increase, drying time was extended. The multiple regression equations for drying characteristics of additive concentration ($X_1$, %), drying time ($X_3$, hr), drying temperature ($X_2$, OC), starch content($X_4$, %) are : $$E(MC)=58.282-5.197X_3-15.151X_4-0.145X_2+2.672X_1\;R^2=0.798\;(NaCl)$$ $$E(MC)=56.651-7.253X_3-0.183X_2-42.844X_1+3.025X_4\;R^2=0.858\;(Sucrose)$$ As starch content, drying temperature and solute concentation increased, he hard ness of model foods increased.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.7
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• pp.662-666
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• 2005

Silicon nitride $(SiN_x)$ film is a promising material for anti-reflection coating and passivation of multicrystalline silicon (me-Si) solar cells. In this work, a plasma-enhanced chemical vapor deposition (PECVD) system with batch-type reactor tube was used to prepare highly robust $SiN_x$ films for screen-printed mc-Si solar cells. The Gas flow ratio, $R=[SiH_4]/[NH_3]$, in a mixture of silane and ammonia was varied in the range of 0.0910.235 while maintaining the total flow rate of the process gases to 4,200 sccm. The refractive index of the $SiN_x$ film deposited with a gas flow ratio of 0.091 was measured to be 2.03 and increased to 2.37 as the gas flow ratio increased to 0.235. The highest efficiency of the cell was $14.99\%$ when the flow rate of $SiH_4$ was 350 sccm (R=0.091). Generally, we observed that the efficiency of the mc-Si solar cell decreased with increasing R. From the analysis of the reflectance and the quantum efficiency of the cell, the decrease in the efficiency was shown to originate mainly from an increase in the surface reflectance for a high flow rate of $SiH_4$ during the deposition of $SiN_x$ films.

• Korean Journal of Plant Taxonomy
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• v.49 no.4
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• pp.371-373
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• 2019

While conducting a floristic study of Korean moss, we discovered one unrecorded species collected from Mt. Hallasan in Korea. Brachydontium olympicum (E. Britton) T. T. McIntosh & J. R. Spence is recorded for the first time for Korea. Unlike other species of Brachydontium, this species has no peristome and its distal laminal cells are mostly isodiametric.

• Structural Engineering and Mechanics
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• v.4 no.1
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• pp.73-89
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• 1996

In Lagrangian mechanics, attention is directed at the body as it moves through space. The region occupied by the body is called a configuration. All body points are labelled by the position they would have if the body were to occupy a chosen reference configuration. The reference configuration can be regarded as an extra fictional copy where notes are kept. As the body moves and deforms, it is important to correctly observe the use of each configuration for computational purposes. The description of strain is particularly important. The present work establishes clearly the role of each configuration in total and in incremental forms. This work also details the differences between gradient and configurational calculus.

• Structural Engineering and Mechanics
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• v.4 no.1
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• pp.91-107
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• 1996

In Lagrangian mechanics, attention is directed at the body as it moves through space. Each body point is identified by the position it would have if the body were to occupy an arbitrary reference configuration. A result of this approach is that the analyst often describes the body by using quantities that may involve more than one configuration. This is particularly common in incremental calculations and in changes of the choice of reference configuration. With the rise of very powerful computing machinery, the popularity of numerical calculation has become great. Unfortunately, the mechanical theory has been evolved in a piecemeal fashion so that it has become a conglomeration of differently developed patches. The current work presents a unified development of the equilibrium principle. The starting point is the conservation of momentum. All details of configuration are shown. Finally, full dynamic and static forms are presented for total and incremental work.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.4
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• pp.507-520
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• 2022

The Sr isotope ratio, which is used as basic data for rock formation time, crustal and mantle evolution studies, is determined by mass spectrometer such as thermal ionization mass spectrometry (TIMS) or multi-detector inductively coupled plasma mass spectrometry (MC-ICP-MS). In this technical report, we compared how incomplete chemical separation of elements affects the determination of Sr isotope ratios. For the experiment, commercial resin, NBS987(NIST SRM987) Sr isotope standard, and rock standard samples from the Geological Survey of Japan (GSJ) such as JG1a, JB3 and JA1 were used. As a result of the comparative experiment, it was clearly observed that the measured values of ⁸⁷Sr/⁸⁶Sr change when Rb remains due to incomplete separation of the NBS987 Sr isotope standard sample as well as the rock standard samples of GSJ. This indicates that complete separation is an important factor since the calculated value deviates from the true value even though correction for isotope interference by isobar is performed when measuring the isotope ratio with MC-ICP-MS. This also suggests that, when reporting the measurement result of Sr isotope ratio using MC-ICP-MS, the measurement strength of ⁸⁵Rb should be reported together with the measurement strength of all isotopes of Sr so that isotope interference by isobar can be judged.