• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.6
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• pp.427-446
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• 2008

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2006 has been accomplished. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environments. The conclusions are as follows. (1) The research trends of fluid engineering have been surveyed as groups of general fluid flow, fluid machinery and piping, etc. New research topics include micro heat exchanger and siphon cooling device using nano-fluid. Traditional CFD and flow visualization methods were still popular and widely used in research and development. Studies about diffusers and compressors were performed in fluid machinery. Characteristics of flow and heat transfer and piping optimization were studied in piping systems. (2) The papers on heat transfer have been categorized into heat transfer characteristics, heat exchangers, heat pipes, and two-phase heat transfer. The topics on heat transfer characteristics in general include thermal transport in a cryo-chamber, a LCD panel, a dryer, and heat generating electronics. Heat exchangers investigated include pin-tube type, plate type, ventilation air-to-air type, and heat transfer enhancing tubes. The research on a reversible loop heat pipe, the influence of NCG charging mass on heat transport capacity, and the chilling start-up characteristics in a heat pipe were reported. In two-phase heat transfer area, the studies on frost growth, ice slurry formation and liquid spray cooling were presented. The studies on the boiling of R-290 and the application of carbon nanotubes to enhance boiling were noticeable in this research area. (3) Many studies on refrigeration and air conditioning systems were presented on the practical issues of the performance and reliability enhancement. The air conditioning system with multi indoor units caught attention in several research works. The issues on the refrigerant charge and the control algorithm were treated. The systems with alternative refrigerants were also studied. Carbon dioxide, hydrocarbons and their mixtures were considered and the heat transfer correlations were proposed. (4) Due to high oil prices, energy consumption have been attentioned in mechanical building systems. Research works have been reviewed in this field by grouping into the research on heat and cold sources, air conditioning and cleaning research, ventilation and fire research including tunnel ventilation, and piping system research. The papers involve the promotion of efficient or effective use of energy, which helps to save energy and results in reduced environmental pollution and operating cost. (5) Studies on indoor air quality took a great portion in the field of building environments. Various other subjects such as indoor thermal comfort were also investigated through computer simulation, case study, and field experiment. Studies on energy include not only optimization study and economic analysis of building equipments but also usability of renewable energy in geothermal and solar systems.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.101-105
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• 2012

'Secret Pink' was released by National Institute of Horticultural & Herbal Science in 2008. The cross was made between '03B1-23' and 'Sei-Monaco in 2005'. After the evaluation of the characteristics under shade culture in summer and retarding culture in spring and consecutive selection from 2006 to 2008, 'Secret Pink' was selected finality. The natural flowering time of 'Secret Pink' was the middle of October, and it is possible to flower all year round by shade and light culture. It has single type flowers with pink petals. The growth of plant was very vigorous and response time was 6.5 weeks. The diameter of flower was 6.7 cm. Number of flowers per stem and petals per flower were 14.5 and 25, respectively. Days to flowering under the short day treatment was about 50 and its vase life was 25.5 days in autumn season.

• Korean Journal of Agricultural Science
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• v.8 no.2
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• pp.212-223
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• 1981

The proper nozzle spacings have been tried to determined the better evenness of distribution on the development of the boom type nozzle system with three nozzles made in Korea-disk type, cap type and bolt type. The operating pressure has been changed in 7 levels ($2kg/cm^2-8kg/cm^2$) and the operating height in 3 levels (30, 40, 50cm) to find characteristics of deposit pattern and the proper spacing of each nozzle was examined and computed. The results of this study were as follows; 1. The CU(%) of the deposit distribution was improved with the operating pressure of $5kg/cm^2$ or $6kg/cm^2$ in Nozzle A with 80% and Nozzle C with 83%, and $7kg/cm^2$in Nozzle B with 80% 2. The better deposit distribution was got ten at operating height 40cm with CU 86% in Nozzle A, and 50cm in both Nozzle B, C with 80% 3. The spray deposit distribution was getting of improvement with decrease of nozzle spacing, nevertheless about half diameter of the spraying circle was recommended in regard to the cost and the work performance. 4. Improvement of quality of nozzles tested in this research may be required not to be less than their CU 90% in the use as boom-type nozzle system.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.268-268
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• 2016

Chemical sensors have attracted much attention due to their various applications such as agriculture product, cosmetic and pharmaceutical components and clinical control. A conventional chemical and biological sensor is consists of fluorescent dye, optical light sources, and photodetector to quantify the extent of concentration. Such complicated system leads to rising cost and slow response time. Until now, the most contemporary thin film transistors (TFTs) are used in the field of flat panel display technology for switching device. Some papers have reported that an interesting alternative to flat panel display technology is chemical sensor technology. Recent advances in chemical detection study for using TFTs, benefits from overwhelming progress made in organic thin film transistors (OTFTs) electronic, have been studied alternative to current optical detection system. However numerous problems still remain especially the long-term stability and lack of reliability. On the other hand, the utilization of metal oxide transistor technology in chemical sensors is substantially promising owing to many advantages such as outstanding electrical performance, flexible device, and transparency. The top-gate structure transistor indicated long-term atmosphere stability and reliability because insulator layer is deposited on the top of semiconductor layer, as an effective mechanical and chemical protection. We report on the fabrication of InGaZnO TFTs with silver nanowire as the top gate electrode for the aim of chemical materials detection by monitoring change of electrical properties. We demonstrated that the improved sensitivity characteristics are related to the employment of a unique combination of nano materials. The silver nanowire top-gate InGaZnO TFTs used in this study features the following advantages: i) high sensitivity, ii) long-term stability in atmosphere and buffer solution iii) no necessary additional electrode and iv) simple fabrication process by spray.

• Journal of the Korean Society for Nondestructive Testing
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• v.29 no.5
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• pp.450-457
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• 2009

Periodical thermal shock can introduce defects in thermal barrier coating made by layers of CoNiCrAlY bond coating(BC) and $ZrO_2-8wt%Y_2O_3$ ceramic top coating(TC) on Inconel-738 substrate using plasma spraying. Thermal shock test is performed by severe condition that is to heat until $1000^{\circ}C$ and cool until $20^{\circ}C$. As the number of cycle is increased, the fatigue by thermal shock is also increased. After test, the micro-structures and mechanical characteristics of thermal barrier coating were investigated by SEM, XRD. The TGO layer of $Al_2O_3$ is formed between BC and TC by periodical thermal shock test, and its change in thickness is inspected by eddy current test(ECT). By ECT test, it is shown that TGO and micro-crack can be detected and it is possible to predict the life of thermal barrier coating.

• Research in Plant Disease
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• v.17 no.3
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• pp.405-409
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• 2011

Azolla Lam. is a small aquatic fern with deeply bilobed leaves, which are consisted of a thick greenish, with chlorophyll, upper (dorsal) lobe and a thinner, translucent lower (ventral) lobe, without chlorophyll, submerged in the water. Azolla blight was observed at a lotus pond. Mycological characteristics of the fungus associated with Azolla blight was immediately determined as Rhizoctonia sp. by the thickness and branching of hypha at right angles at the point toward the distal end of septa, with branching hypha is constricted. The fungus produced brown mycelia and dark brown sclerotia on PDA. The optimum temperature for mycelial growth and sclerotia formation were $25^{\circ}C$ and $30^{\circ}C$, respectively. The optimum temperature for fungal infection was $30^{\circ}C$, when spray inoculated. Phylogenetic analysis of rDNA-ITS revealed that the fungus was identified as Rhizoctonia solani (AG-1 IA) closest to one causing rice sheath blight disease. This is the first report on the blight disease of Azolla caused by R. solani in Korea.

• The Korean Journal of Pesticide Science
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• v.19 no.2
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• pp.93-100
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• 2015

This study surveyed the selling, buying, usage, selection and spraying frequency of pesticides on apple orchards in Geochang, Gyeongsangnam-do province from 2012 to 2013 and found that the fungicides, insecticides and acaricides were sprayed $13.9{\pm}3.5$, $12.6{\pm}3.2$, and $2.6{\pm}1.3$ times per year, respectively. Fungicides were applied mainly to control for Diplocarpon mali, Colletotrichum gloeosporoides and Alternaria mali, whereas insecticides were sprayed mostly to control Grapholita molesta, Carposina sasakii insects. Dealers sold pesticides without monitoring of the pests in the apple orchards, and also sometimes sold pesticides which are non-registered for apple. Most of the farmers were highly relied on dealers' recommendations to choosing the brand product. Relating on Integrated Pest Management (IPM) on apple orchards in Geochang, residual active ingredient of frequently sprayed fungicides, insecticides, and acaricides were analyzed. Most applications of the fungicides, insecticides and acaricides were well corresponded with FAO's recommendations. For production of safe food and use of pesticides, it is requested to develope control calender and consideration of training program for farmers. The regional characteristics and environmental situation of the farm also should be considered.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.6
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• pp.268-273
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• 2014

$Y_2O_3$ ceramic specimens were fabricated from the granular powder, obtained by spray drying process from the slurry. The slurry was prepared by mixing PVA binder, NaOH for Ph control, PEG and $Y_2O_3$ powder. The $Y_2O_3$ specimen was shaped in size of ${\phi}14mm$ and then sintered at $1650^{\circ}C$. The characteristics, microstructure, densities and plasma resistance of the $Y_2O_3$ specimens were investigated with the function of forming pressure and sintering time. $Y_2O_3$ specimens were exposed under the $CHF_3/O_2/Ar$ plasma, the dry etching treatment of specimens was carried out by the physical reaction etching of $Ar^+$ ion beam and the chemical reaction etching of $F^-$ ion decomposed from $CHF_3$. With increasing sintering time, $Y_2O_3$ specimens showed relatively high density and strong resistance in plasma etching test.

• Research in Plant Disease
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• v.22 no.4
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• pp.293-296
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• 2016

In late June 2016, stalk rot symptoms were observed on five vatieties of sorghum (Sorghum bicolar) at organic paddy-upland rotation system in Anseong city, Korea. The initial symptom on stalk surfaces was red color with a dark red spot lesion. A fungus was isolated from the initial lesion, and cultured on potato dextrose agar. Size of microconidia mostly extend to $5-19{\times}2-{\mu}m$ in culture, with 0-1 septa and macroconidia extend to $29-52{\times}3-4{\mu}m$ with 4-6 septa. Pathogenicity was investigated using conidial suspension spray to seedling of sorghum. After 3 days of inoculation, the dark red lesion was produced on stalks. On the basis of mycological characteristics, pathogenicity, and internal transcribed spacer (ITS) rDNA sequence analysis, this fungus was identified as Fusarium thapsinum. This is the first report of stalk rot on sorghum caused by F. thapsinum in Korea.

• KSBB Journal
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• v.23 no.1
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• pp.65-69
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• 2008

The culture broth of a ${\beta}$-glucan-producing bacterium, Paenibacillus polymyxa JB115, was confirmed to show the antibiosis against pathogenic bacteria of livestock disease. The antibacterial substance produced by P. polymyxa JB115 exhibited strong bactericidal or bacteriostatic effect on the growth of livestock pathogenic bacteria including Staphylococcus aureus, Salmonella choleraesuis, Escherichia coli and Pseudomonas aeruginosa. This antibacterial substance also showed high stabilities in broad pH range (pH 3-11) and in broad temperature range $(40-121^{\circ}C)$, which is good enough to apply spray-dry method for the formulation of culture broth. It was also found that the antibacterial substance was very stable in artificial gastric fluid and bile acid, which implies the anticipated antibacterial activity against gastrointestinal bacteria harmful for livestocks. In conclusion, the culture broth of P. polymyxa JB115 can be developed as a multifuctional feed additive containing immune-enhancing ${\beta}$-glucan as well as antibacterial agent against livestock pathogenic bacteria.