• Journal of the Korean Wood Science and Technology
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• v.44 no.6
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• pp.903-912
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• 2016

Morphological and anatomical evaluation of grafted P. merkusii have been undertaken to obtain the information about compatible and incompatible symptoms of 18 years old grafts based on morphological observation and microscopic analysis. Samples of compatible and incompatible grafts were obtained from previous research conducted by the Silviculture Departement Team in 1994. Result showed that compatible grafts have normal stem form and secondary growth (diameter growth), but some abnormality symptoms like undulated pattern of annual growth rings, phloem thickening and abnormality resin ducts in inner and middle parts of the union area occurred. Incompatible ones showed abnormality of the stem form, cortex-bark necrosis and swelling in the union area. Microscopic observation showed abnormality of all parts of the union, undulated pattern of annual growth rings, phloem thickening, abnormal resin ducts, low numbers and discontinuity of vascular elements in the union area.

• Mycobiology
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• v.31 no.1
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• pp.42-45
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• 2003

For transformation of Pleurotus ostreatus, two novel vectors, pPhKM1 and pPhKM2, were constructed, using the regulatory sequences of the P. sajor-caju $\beta$-tubulin gene(TUB1) and the ble gene encoding phleomycin binding protein. pPhKM1 contains ble fused to the TUB1 promoter and the Schizophyllum commune GPD terminator. pPhKM2 contains ble fused to the promoter and terminator regions of P. sajor-caju TUB1. To confirm phleomycin-resistance activity, each vector was cotrans-formed with pTRura3-2 into the P. ostreatus homokaryotic $ura^-$ strain. The transforming DNA was stably integrated into the genomic DNA. Subsequently, phleomycin resistance was conferred on wild-type dikaryotic P. ostreatus by transformation with pPhKM1 or pPhKM2. This transformation system generated stable phleomycin-resistant transformants.

• Journal of Biosystems Engineering
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• v.22 no.3
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• pp.289-294
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• 1997

The chestnut is a well-known and important forest product in Korea. The annual production of chestnut is about 100, 000tons and its cultivating area is 80, 000ha. However, the peeling process of outer and inner skins of chestnut is very difficult due to hardness and adhesiveness of chestnut skin. The peeling process of chestnut was operated by manual work and the performance of chestnut peeling machine is very low. The purpose of this study is to develope the prototype of new chestnut peeling system. The hardness of chestnuts was tested with six different drying conditions and its range was from 949$g/mm^2$ to 2, 149$g/mm^2$. The hardness of chestnuts was decresed gradually during the drying process. The chestnut peeling Process includes sorting, storage, drying, outer skin cutting, flame peeling, continuous frictional skin peeling, and inner skin cutting operation. The developed chestnut peeling system consists of outer skin cutter, flame peeler, continuous frictional skin peeler and inner skin cutter. The system can peel domestic chestnuts at 150$kg/hr$ with peeling rate of 78%.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.1
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• pp.18-28
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• 1998

The main protein peak was observed in fraction No.9 and 109 when cellulase seperation was conducted by use of DEAE-Sephadex. The protein obtained from fraction No.9 has the characteristics of Cx component and that from fraction No.109 characteristics similiar to $C_1$ component. The effective reaction condition of the ensyme used was $40^{\circ}C$ in temperature. pH 5.0 and 90 minutes in treatment time. For the case of $C_1$ pH 5.5 in temperature range of $30^{\circ}C 50^^{\circ}C$, 4.0 5.5 in pH, and over 30 minutes of treatment time, the reaction was in the range of 80% of the maximum. Affinity of enzyme increased as freeness, increased, and this effect was more visible in fiber than in fines.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.347-349
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• 2009

Unmanned helicopters are needed in various fields such as monitoring system, agriculture and forest fire. Swash plate is a essential part for exact driving of unmanned helicopter. And it is usually produced by machining. In this research, hot forging process of upper swash plate has been studied to improve proof stress against repeated loading of the product. In the forming analysis, design parameters such as effective stress, effective strain and distribution of damage have been considered in the hot forging.

• Journal of Information Technology Services
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• v.14 no.4
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• pp.159-169
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• 2015

Customer reviews are one of the important sources for purchase decision makings in online stores. Online stores have tried to provide useful reviews in product pages to customers. To assess the usefulness of customer reviews before other users have voted enough on the reviews, diverse aspects of reviews were utilized in prevous studies. Style and semantic information were utilized in many studies. This study aims to test diverse alogrithms and datasets for identifying a proper classification method and threshold to classify useful reviews. In particular, most researches utilized ratio type helpfulness index as Amazon.com used. However, there is another type of usefulness index utilized in TripAdviser.com or Yelp.com, count type helpfulness index. There was no proper threshold to classify useful reviews yet for count type helpfulness index. This study used reivews and their usefulness votes on restaurnats from Yelp.com to devise diverse datasets and applied text mining approaches to classify useful reviews. Random Forest, SVM, and GLMNET showed the greater values of accuracy than other approaches.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2008.10a
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• pp.153-161
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• 2008

Agriculture and forest are basis for livelihood in Nepal while both sectors constitute around 40 percent of the national product and over two-thirds of the economically active population is dependent on agriculture. However, radical changes in land use, depletion in crops production and food availability are major threats due to loss of soil fertilityand severe environmental degradation. In this study, we used time series data from 1986/87 to 2005/06 about food crop production and population published by Government of Nepal, Ministry of Agriculture and Cooperatives and Central Bureau of Statistics. Descriptive statistics and ArcGIS were used to assess and map the food security status of Nepalese Terai based on the local food demand and supply system. Food supply to demand ratio(FSDR) was the main idea of assessment. Our results showed that out of 20 districts, only 8 districts were categorised under secured food districts whereas 5 districts were still under food unsecured situation. The analysis further revealed that 7 districts had faced food deficit more than 8-16 times during the last 20 year periods. Data further showed that there was surplus food supply relative to the requirements dictated by FSDR. However, the average FSDR was less than 1.2(less than 20% surplus) exploring fact that most of the districts were not producing sufficient food to cope up the food shock and after 1995 it was relatively stagnant. Our prediction reveals that food supply in Terai even in the future would remain at almost the same level as now, and there will not more than 16-17% surplus by 2021 considering medium vibrant population growth. The findings thus, indicate that Terai may not be a food secure region in the future, even though the region is considered as a food storage house of Nepal. In addition, this paper suggests ways to make future comprehensive case studies more widely comparable in Terai, Nepal.

• The Plant Pathology Journal
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• v.22 no.2
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• pp.125-130
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• 2006

An isolate of Peanut stunt virus (PSV) isolated from black locust tree (Robinia pseudo-acacia L.) showing severe mosaic and malformation symptoms, was designated as PSV-Rp. PSV-Rp was characterized by the tests of host range, physical properties, RNA and coat protein composition and RT-PCR analysis. Nucleotide sequences of the cucumoviruses CP genes were also used for identification and differentiation of PSV-Rp. Six plant species were used in the host range test of PSV-Rp. PSV-Rp could be differentiated from each Cucumovirus strain used as a control by symptoms of the plants. The physical properties of PSV-Rp virus were TIP $65^{\circ}C$, DEP $10^{-3}$, and LIP $2{\sim}3$ days. In dsRNA analysis, PSV-Rp consisted of four dsRNAs, but satellite RNA was not detected. Analysis of the coat proteins by SDS-PAGE showed one major protein band of about 31 kDa. RT-PCR using a part of Cucumovirus RNA3 specific primer amplified ${\sim}950bp$ DNA fragments from the crude sap of virus-infected black locust leaves. RFLP analysis of the RT-PCR product could differential PSV-RP from CMV The nucleotide sequence identity between the PSV-Rp CP and the TAV-P CP genes and the PS-V-RP CP and CMV-Y CP genes were 61.6% and 40.5%, respectively. On the other hand, the nucleotide sequence identity of the PSV-Rp CP gene was $70.9%{\sim}73.4%$ in comparison with those of PSV subgroup I (PSV-ER and PSV-J) and 67.3% with that of PSV subgroup II(PSV-W). Especially, the nucleotide sequence identity of PSV-Rp CP gene and that of PSV-Mi that was proposed recently as the type member of a novel PSV subgroup III was 92.4%.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.3
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• pp.169-176
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• 2002

To determine availability as a feed source of deer of by-products that produced at reforestation areas and comprised shrubs and wild grasses, mixed forest by-product silage(FBS), arrowroot silage(ARS), bristletooth oak tree silage(BOS), white oak tree silage(WOS) were prepared to compare dry matter intake, digestibility and nitrogen balance in digestion balance trials with spotted deer. Dry matter intake was highest in WOS and lowest in ARS but there was no significant difference(P＞0.05). Digestible dry matter intake was higher in FBS and ARS that had higher dry matter digestibility than in WOS and BOS that had lower dry matter digestibility(P＞0.05). Dry matter digestibility was highest fur ARS and lowest for BOS(P＜0.05). Digestibility of crude protein was similar to that of dry matter. That of crude fiber was higher for FBS and ARS than for BOS and WOS(P＞0.05). Daily gain of body weight was slightly greater for WOS than fer other treatments(P＞0.05). Nitrogen intake was highest for ARS and lowest for BOS(P＜0.05), and fecal nitrogen was opposite to nitrogen intake(P＜0.05). Nitrogen excretion with urine was highest for ARS that had higher nitrogen intake and lowest for BOS and there was a significant difference(P＜0.05). Retained nitrogen was highest for FBS and lowest for. BOS (P＞0.05). Although there was no significant difference(P＞0.05): the ration of nitrogen intake to retained nitrogen was highest in FBS for 43.9% and lowest in BOS for 24.7%. Consequently because by-products that produced at reforestation areas had high intake and internal availability, it was evaluated to valuable feed source for deer.

• Research in Plant Disease
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• v.24 no.4
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• pp.353-358
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• 2018

An effective bioformulation of mixtures of chitin-degrading bacteria has been used successfully to control plant diseases and nematodes. In this study, the bioformulation approach was assessed to control damping-off disease of ginseng. In pot experiments with soils infested with dapming-off pathogens of ginseng, root-drenchings of Chrobacterium sp. C-61, Lysobacterium enzymogenes C-3, and mixture of two bacterial strains grown in chitin minimal medium were signficantly increased emergence of seeds and reduced damping-off disease incidence of seedlings. Efficacy of the bioformulated product depended on the dose and timing of application. In two-year-old ginseng field, the high control efficacies were achieved by soil drenching of two times with an undiluted product or three times with a 10-fold diluted product. In a To-jik nursery (self soil nursery), biocontrol efficacy of the undiluted product against damping-off disease were similar to that of a seed dressing with fungicide, Tolclofos-methyl WP. These results suggest that the bioformulated product containing Chromobacterium sp. C-61 and L. enzymogenes C-3 could be an effective approach to control of ginseng damping-off disease.