• The Korean Journal of Mycology
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• v.43 no.3
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• pp.158-164
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• 2015

A total of 509 rice panicle samples were collected at harvest time from fields in 8 provinces from 2010 to 2014. One hundred five grains per sample were plated on potato dextrose agar and 6,658 Fusarium isolates were obtained; among them, 67 were identified as Fusarium armeniacum by sequencing the translation elongation factor $1{\alpha}$ ($EF-1{\alpha}$) and confirmed by their morphological and cultural characteristics. Considerable variation in conidial size, colony color and $EF-1{\alpha}$ sequences was observed among the fungal isolates. The ability of 24 F. armeniacum isolates to produce T-2 and HT-2 toxin in potato sucrose agar was determined using liquid chromatography-mass spectrometry. Twenty one isolates produced T-2 and HT-2 toxin, resulting in varying toxin levels among the isolates. The results show that Korean isolates of F. armeniacum have diversity with respect to morphological, cultural, genetic, and toxigenic properties.

• The Journal of the Petrological Society of Korea
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• v.11 no.2
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• pp.65-73
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• 2002

The wavy extinction of quartz grains can be used as a good indicator to show the degree of rock deformation. To determine degree of the rock deformation, intensity of wavy extinction (IWE) of quartz grains was measured by using polarizing microscope, digital camera, and NIH image (or Scion Image). In this experiment, the measurement was performed along the line perpendicular to the subgrain boundary of wavy extinction. IWE was measured when a quartz grain shows maximum extinction in polarizing microscope. NIH image was represented in terms of 256 gray-scale brightness, which was associated with intensity of the wavy extinction. IWE was determined by the degree of brightness versus the measuring length of a quartz grain. IWE was analysed in the distribution chart with the collection unit of 5. Regarding the characteristics of data distribution, the median between the mode and the median of the histogram is defined as a representative value for the IWE, and this value is subdivided into the five levels of rock deformation zones (lowest- or non-, low-, medium-, high-, and highest deformation) with their respective indices (D1, D2, D3, D4, and D5). The correlation between the Eonyang Granite and the Yangsan Fault was investigated by using the indices. The results indicate that IWE values decreased away from the fault.

• Applied Microscopy
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• v.36 no.3
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• pp.195-208
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• 2006

Using light and scanning electron microscopy morphological studies of pollens were conducted to determine the sectional boundary and the relationships among eight species of section Zygophyllidium and its five related species of subg. Poinsettia. Pollen characters of 13 species were described, and their diagnostic keys were presented here. Based on the sculpturing patterns and the results of numerical analysis using 10 pollen characters 13 species were divided into four Pollen types: type I, having micro-reticulate shaped pollen (E. hexagona, E. lagunensis, E. hexagonoides and E. bilobata), type II, having reticulate shaped pollen (E. delicatula, E. extipulata, E. dentata, E. heterophylla, E. pulcherrima and E. cyathophora), type III, micro-reticulate shaped pollen with platten muri (E. lacera), and type IV, haying foveolate shaped pollen grains (E. chersonesa and E. eriantha). The results of pollen morphological studies suggest that the sect. Zygophyllidium should be delimited based on only four species, E. hexagona, E. lagunensis, E. hexagonoides and E. bilobata, E. delicatural and E. exstipulata of sect. Zygophyllidium must be transferred to subg. Poinsettia based on pollen morphology. E. eriantha and E. chersonesa having forveolate sculpturing pattern of pollen grains seem to be closely related with species from subg. Agaloma, and additional studies of these species are needed to determine the species relationships within Agaloma group.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.154-155
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• 2012

The promise of nano-crystalites (nc) as a technological material, for applications including display backplane, and solar cells, may ultimately depend on tailoring their behavior through doping and crystallinity. Impurities can strongly modify electronic and optical properties of bulk and nc semiconductors. Highly doped dopant also effect structural properties (both grain size, crystal fraction) of nc-Si thin film. As discussed in several literatures, P atoms or radicals have the tendency to reside on the surface of nc. The P-radical segregation on the nano-grain surfaces that called self-purification may reduce the possibility of new nucleation because of the five-coordination of P. In addition, the P doping levels of ${\sim}2{\times}10^{21}\;at/cm^3$ is the solubility limitation of P in Si; the solubility of nc thin film should be smaller. Therefore, the non-activated P tends to segregate on the grain boundaries and the surface of nc. These mechanisms could prevent new nucleation on the existing grain surface. Therefore, most researches shown that highly doped nc-thin film by using conventional PECVD deposition system tended to have low crystallinity, where the formation energy of nucleation should be higher than the nc surface in the intrinsic materials. If the deposition technology that can make highly doped and simultaneously highly crystallized nc at low temperature, it can lead processes of next generation flexible devices. Recently, we are developing a novel CVD technology with a neutral particle beam (NPB) source, named as neutral beam assisted CVD (NBaCVD), which controls the energy of incident neutral particles in the range of 1~300eV in order to enhance the atomic activation and crystalline of thin films at low temperatures. During the formation of the nc-/pm-Si thin films by the NBaCVD with various process conditions, NPB energy directly controlled by the reflector bias and effectively increased crystal fraction (~80%) by uniformly distributed nc grains with 3~10 nm size. In the case of phosphorous doped Si thin films, the doping efficiency also increased as increasing the reflector bias (i.e. increasing NPB energy). At 330V of reflector bias, activation energy of the doped nc-Si thin film reduced as low as 0.001 eV. This means dopants are fully occupied as substitutional site, even though the Si thin film has nano-sized grain structure. And activated dopant concentration is recorded as high as up to 1020 #/$cm^3$ at very low process temperature (＜ $80^{\circ}C$) process without any post annealing. Theoretical solubility for the higher dopant concentration in Si thin film for order of 1020 #/$cm^3$ can be done only high temperature process or post annealing over $650^{\circ}C$. In general, as decreasing the grain size, the dopant binding energy increases as ratio of 1 of diameter of grain and the dopant hardly be activated. The highly doped nc-Si thin film by low-temperature NBaCVD process had smaller average grain size under 10 nm (measured by GIWAXS, GISAXS and TEM analysis), but achieved very higher activation of phosphorous dopant; NB energy sufficiently transports its energy to doping and crystallization even though without supplying additional thermal energy. TEM image shows that incubation layer does not formed between nc-Si film and SiO2 under later and highly crystallized nc-Si film is constructed with uniformly distributed nano-grains in polymorphous tissues. The nucleation should be start at the first layer on the SiO2 later, but it hardly growth to be cone-shaped micro-size grains. The nc-grain evenly embedded pm-Si thin film can be formatted by competition of the nucleation and the crystal growing, which depend on the NPB energies. In the evaluation of the light soaking degradation of photoconductivity, while conventional intrinsic and n-type doped a-Si thin films appeared typical degradation of photoconductivity, all of the nc-Si thin films processed by the NBaCVD show only a few % of degradation of it. From FTIR and RAMAN spectra, the energetic hydrogen NB atoms passivate nano-grain boundaries during the NBaCVD process because of the high diffusivity and chemical potential of hydrogen atoms.

• Magazine of the Korean Society of Agricultural Engineers
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• v.11 no.1
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• pp.1598-1603
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• 1969

A field expeperiment has been conducted in order to explore possibilities of efficient and economical irrigation methods for the rice cultivation through which irrigation water may be saved and rice paddies may keep water for longer period of time, resulting in an increased yield of rice. Some of the major findings from the experimentation are summarized in the following. 1. There is slightly significant difference among experimental plots in the weight of rice straw. 2. The 9cm-lined plot proves to be the best in terms of the thickness. In this connection, however, it seems to by 3cm. 3. The wheat straw-lined plot is found superior in yield. However, this may be resulted in by the application of more fertilizer, and how long the plot could be durable may be problematic. Since every two or three years the straw-lining work has to be done, more labour may be required of the plot. 4. It would be inappropriate to expect any meaningful experimental results for the first year, since surface soil and deep soil are mixed up in the course of work. There is not observed any meaningful difference in the number of ears per stalk and in the number of grains per ear. However, in the lined plots, the number of tillers is slightly increased. 5. Irrigation has been applied by means of ordinary method after lining. When irrigation is applied at the interval of five to six days, irrigation water is saved by 44.9 per cent in the case of 9cm-lined plot, 39.7 per cent in the case of 6 cm-lined plot, and 36.3 percent in the case of 3 cm-lined plot. 6. An increased yields arenoted in the wheat straw-lined plot by 23.8 per cent, in the 9 cm-lined plot by 20.1 per cent, in the 3 cm-lined plot by 12 per cent. and in the case of vinyl-lined plot by 12.5 per cent. 7. The rate of maturity of grains is proved better, and the husking rate also found better(75%), that is, the quality of rice grains is improved.

• Korean Journal of Agricultural Science
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• v.34 no.1
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• pp.53-60
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• 2007

A layer feeding trial was conducted for 10 weeks to investigate the effects of the addition of corn distillers dried grains with solubles (DDGS) to layer diets on the laying performance, egg qualities, and yolk fatty acid composition. Nine hundred Hyline Brown layers, 24 weeks of age,were randomly allotted to 20 replicate laying cages, 45 birds per replicate. There were four diet treatments (0, 10, 15, and 20% DDGS), and five replicates per treatment. All experimental diets were prepared to contain iso-protein (17%) and iso-calorie (TMEn 2,780 kcal/kg). The use of DDGS up to 20% level in layer diets did not exert any influence on feed intake, laying rate, total egg mass, mean egg weight, and feed conversion ratio. DDGS did not exert any influence in weight of egg, breaking strength, and color of eggshell. The albumen height and Haugh unit was not influenced by DDGS addition. The yolk color was significantly increased by DDGS supplementation. As the DDGS level increased, the oleic acid content decreased, and the linoleic acid increased (P<0.05). The degree of saturation of yolk fatty acids was not affected by dietary DDGS. The inclusion of DDGS up to 20% in layer diets resulted in the decrease of feed cost per kg without any effect in the laying performance. In conclusion, the use of DDGS up to 20% level in layer diets could replace corn and soybean meal without any harmful effect on the laying performances.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.5
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• pp.721-738
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• 2015

This research analyzed emergency foods in Korea during the Japanese occupation through the food literature of that era, and attempted to determine the cultural history of food through recorded contents of emergency foods literature. The examination was mainly conducted on the basis of the four excerpts within the emergency foods literature of the Japanese occupation: "Emergency plants of the Joseon", "Wild Fruits and Plants of the Joseon", "Guhwangginam", and "Emergency Plants and How to Eat of the Joseon". After a thorough examination, each of the excerpts had unique data regarding amounts of ingredients, such as Namuls, trees, grain, and beans. "Emergency Plants of the Joseon" listed 142 Namuls, 54 trees,"Wild Fruits and Plants of the Joseon" listed 32 Namuls, 29 trees, "Guhwangginam" 4 grains, 205 Namuls, 84 trees, "Emergency Plants and How to Eat of the Joseon" listed five grain, three beans, 37 Namuls, and eight trees. Emergency foods literature demonstrated the utilization of various wild and edible plants as excellent ingredients for meals. Additionally, changes in traditional cooking methods using sugar, preservation through canning, and frying substantiate the subtle influence of foreign influence on Korean food. Perhaps the carefully structured components of the Korean food can be interpreted as a direct result of a scientific approach. It can be argued that creative application of methods ingredients, approach, of emergency foods is necessary to this modern age.

• Journal of Korean Society of Forest Science
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• v.85 no.3
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• pp.472-486
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• 1996

The pollen morphology of 19 species and 1 variety of the genus Acer L. in Korea was investigated by light and scanning electron microscopy. The results are as follows ; 1. A. pollen key of the genus Acer L. in Korea was provided in four types. 2. Based on the aperture types and sculpture patterns, the four major pollen types of the genus Acer L. in Korea were recognized which included palmatum, barbinerve, negundo and saccharum types. 3. Pollen grains are tricolpate or tricolporate on the aperture, and striate, rugulate or reticulate on the sculpture pattern. 4. As the result of the correlation analysis between the five measured pollen parameters in pairs, a highly significant positive correlation was found between polar axis length(PL) and colpus length (CL).

• Current Photovoltaic Research
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• v.7 no.4
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• pp.103-110
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• 2019

Cu(In,Ga)₃Se₅ (β-CIGS) has a band gap of 1.35 eV, which is an optimum value for high solar-energy conversion efficiency. The effects of Cu and Ga content on the cell performance were investigated previously. However, the effect of Se content on the cell performance is not well understood yet. In this work, β-CIGS films were fabricated by three-stage co-evaporation of elemental sources with various Se fluxes at the third stage instead of at all stages. The average composition of five samples was Cu_1.05(In_0.59,Ga_0.41)3Se_y, where the stoichiometric y value is 5.03 and the stoichiometric Se/metal (Se/M) ratio is 1.24. We varied the Se/metal ratio in a range from 1.18 to 1.28. We found that the best efficiency was achieved when the Se/M ratio was 1.24, which is exactly the stoichiometric value where the CIGS grains on the CIGS surface were tightly connected and faceted. With the optimum Se/M ratio, we were able to enhance the cell efficiency of a β-CIGS solar cell from 9.6% to 12.0% by employing a Na₂S post deposition treatment. Our results indicate that Na₂S post deposition treatment is very effective to enhance the cell efficiency to a level on par with that in α-CIGS cell.

• Journal of Biosystems Engineering
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• v.27 no.3
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• pp.219-226
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• 2002

Desorption equilibrium moisture contents of oak mushroom were measured by the static method using salt solutions at flour temperature levels of 35$\^{C}$, 45$\^{C}$, 55$\^{C}$ and 6$\^{C}$ and five relative humidity levels in the range from 11.0% to 90.8%. EMC data were fitted to the modified Henderson, Chung-Pfost, modified Halsey and modified Oswin models using nonlinear regression analysis. Drying tests far oak mushroom were conducted in an experimental dryer equipped with air conditioning unit. The drying test were performed in triplicate at flour air temperatures of 35$\^{C}$, 45$\^{C}$, 55$\^{C}$ and 65$\^{C}$ and three relative humidities of 30%, 50% and 70% respectively. Measured moisture ratio data were fitted to the selected four drying models(Lewis, Page, simplified diffusion and Thompson models) using stepwise multiple regression analysis. The results of comparing root mean square errors for EMC models showed that modified Halsey was the best model, and modified Oswin models could be available far oak mushroom. The results of comparing coefficients of determination and root mean square errors of moisture ratio for four drying models showed that Page model were found to fit adequately to all drying test data with a coefficient of determination of 0.9990 and root mean square error of moisture ratio of 0.00739.