• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.1
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• pp.30-33
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• 2006

Transparent indium tin oxide (ITO) anode surface was modified using $O_3$ Plasma and organic ultrathin buffer layers were deposited on the ITO surface using 13.56 MHz RF plasma polymerization technique. The EL efficiency, operating voltage and lifetime of the organic light-emitting device (OLED) were investigated in order to study the effect of the plasma surface treatment and role of plasma polymerized organic ultrathin buffer layer. Poly methylmethacrylate (PMMA) layers were plasma polymerized on the ITO anode as buffer layer between anode and hole transport layer (HTL). The plasma polymerization of the organic ultrathin layer were carried out at a homemade capacitive-coupled RF plasma equipment. N,N'-diphenyl-N,N'(3- methylphenyl)-1,1'-diphenyl-4,4'-diamine (TPD) as HTL, Tris(8-hydroxyquinolinato) Aluminum $(Alq_3)$ as both emitting layer (EML)/electron transport layer (ETL), and aluminum layer as cathode were deposited using thermal evaporation technique. Effects of the plasma surface treatment of ITO and plasma polymerized buffer layers on the OLED performance were discussed.

• Korean Journal of Metals and Materials
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• v.49 no.5
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• pp.400-405
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• 2011

ZnO nanotube arrays were synthesized by a two-step process: electrodeposition and selective dissolution. In the first step, ZnO nanorod arrays were grown on an Au/Si substrate by using a homemade electrodeposition system. ZnO nanorod arrays were then selectively dissolved in an etching solution composed of 0.125 M NaOH, resulting in hollow ZnO nanotube arrays. It is suggested that the formation mechanism of the ZnO nanotube arrays might be attributed to the preferred surface adsorption of hydroxide ion ($OH^{-1}$) on a positive polar surface followed by selective dissolution of the metastable Zn-terminated ZnO (0001) polar surface caused by the difference in the surface energy per unit area between the ZnO nanorod and nanotube.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.1
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• pp.131-146
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• 2021

Multimodal biometric-based recognition has been an active topic because of its higher convenience in recent years. Due to high user convenience of finger, finger-based personal identification has been widely used in practice. Hence, taking Finger-Print (FP), Finger-Vein (FV) and Finger-Knuckle-Print (FKP) as the ingredients of characteristic, their feature representation were helpful for improving the universality and reliability in identification. To usefully fuse the multimodal finger-features together, a new robust representation algorithm was proposed based on hierarchical model. Firstly, to obtain more robust features, the feature maps were obtained by Gabor magnitude feature coding and then described by Local Binary Pattern (LBP). Secondly, the LGBP-based feature maps were processed hierarchically in bottom-up mode by variable rectangle and circle granules, respectively. Finally, the intension of each granule was represented by Local-invariant Gray Features (LGFs) and called Hierarchical Local-Gabor-based Gray Invariant Features (HLGGIFs). Experiment results revealed that the proposed algorithm is capable of improving rotation variation of finger-pose, and achieving lower Equal Error Rate (EER) in our homemade database.

• Journal of Apiculture
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• v.34 no.4
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• pp.325-328
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• 2019

We investigated the food storage stability of propolis extracts using homemade meatballs. Propolis extracts were prepared by using the ethanol extraction method. After making the meatballs, propolis was mixed into the meatball materials and egg water with a final concentration of 1% v/v. Microbial cultivation results showed that the cultivation of Staphylococcus aureus, which is one of the food poisoning bacteria, was reduced by more than 90% and the period of storage was 1.5 times longer. Also, it was observed to be effective when propolis was added to meatballs, it was even more effective when propolis was mixed with egg water. Thus, propolis extracts may be a useful ingredient for food storage stability due to its anti-microbacterial function.

• Human Ecology Research
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• v.61 no.1
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• pp.29-38
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• 2023

This study examined changes in dietary life and dietary life satisfaction in one-person households during the COVID-19 pandemic. Using a sample of 916 one-person households from the Food Consumption Behavior Survey, we applied ANOVA and a system of equations model for our analysis which produced four main results. Firstly, during the COVID-19 pandemic, eating homemade and delivered meals increased, whereas eating restaurant, group, and HMR meals decreased. Eating breakfast and regular eating habits also increased during the pandemic. Secondly, approximately 30% of the sample reported increased expenditure on fresh food and HMR meals. The proportion of positive changes in dietary life was also greater than negative changes, and dietary life satisfaction was about three times higher than it had been before the pandemic. Thirdly, having breakfast and regular eating fully mediated the relationship between spending on fresh food and dietary life satisfaction, as well as the relationship between HMR purchases and dietary life satisfaction. Changes in expenditure on fresh food and HMR meals positively affected dietary life satisfaction through eating breakfast and regular eating. Fourthly, increased consumption of delivered food had a positive direct effect on dietary life satisfaction. Among sociodemographic variables, gender, education, occupation, and age were also significantly related to changes in dietary life satisfaction.

• The Journal of the Acoustical Society of Korea
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• v.28 no.2
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• pp.127-134
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• 2009

In this study, possibility of the laser eavesdropping is investigated on the window glasses with various thicknesses, Glass windows are excited by maximum length sequency (MLS) signal and the vibration sound is detected by a laser doppler vibrometer. From the detected sound, speech intelligibility is objectively estimated. Speech transmission index (STI), which is based on the modulation transfer function (MTF). is calculated for the estimation. Finally, disturbing wave effect on the speech intelligibility is analysed by using an outside speaker and a window shaker attached on the glass window. The purpose of the study is to estimate the possibility of remote eavesdropping by the laser sensor and to evaluate the performance of the homemade window shaker to protect from the remote eavesdropping.

• Journal of the Korean Electrochemical Society
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• v.16 no.1
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• pp.46-51
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• 2013

In order to monitor in situ electrochemical reaction we prepared the gold microshells on silica microspheres of $2{\mu}m$ in diameter which were able to not only work as electrodes but also surface enhanced Raman scattering (SERS) active substrates. Previously reported gold microshell using polystyrene as core material have a few serious problems, mostly coming from solubility in organic solvent, nonuniform distribution in size and toxicity of the polystyrene. Here we prepared silica core-gold microshell to obtain a strong SERS active platform benefitting from the physicochemical stability, uniformity and non-toxicity of silica. Varying the concentration of 3-aminopropyl triethoxysilane (APTES), the surfaces of silica beads were modified and the optimal condition was determined to be 1% APTES that made the SERS activity of gold microshell strongest. The gold microshells as made were characterized by homemade Micro-Raman system spectrometer, Field-Emission Scanning Electron Microscope.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.4
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• pp.301-305
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• 1986

This study was conducted to develop the homemade soil media adequate to raising rice seedlings for machine transplanting. A raising experiment of rice seedlings was tested on a newly developed soil medium made mainly from briquette ash compared to ones of infertile red earth and fertile paddy loams. Dry weight of rice seedlings at 36 days after seeding was slighly lower in the plot of briquette ash that in soils, however, it was quite good in the plot of briquette ash mixed with zeolite and diatomaceous earth. pH in soil media was high in briquette ash and also high in soils mixed compost compared with out compost treatment, resulting in higher occurrence of damping off or physiological disorder. Good rice seedlings could be raised in soil media without compost and briquette ash mixed with zeolite diatomaceous earth.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.3
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• pp.167-175
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• 2003

This study was conducted to investigate the actual state of the food allergy and food behavior in adults by using a questionnaire. The subjects of this study were consisted of 207 males and 355 females in Gyeongbuk area. The results are as follows: Among the respondents, 54.9% kept up with proper eating habits, 41.2% knew how much they would have to eat appropriately in a day, and women ate more milk and snacks than men in a day and men ate more meat than women. 58.3% of men and 46% of women were eating 3 meals a day. This finding indicated that women skipped the meal more than men. 77.2％ of the respondents skipped their breakfast, 13.5％ the lunch, and 9.3% the dinner. 48.5％ of men and 28.8% of women evacuated over 8 times a week(p<0.001). Eczema was the allergy symptom which broke out the most highly in both male and female; 25% of men and 29.9% of women. Atopic dermatitis and pollen allergy broke out similarly in both male and female. Allergic rhinitis occurred twice more in men than in women. Asthma broke out in men about three times more than in women. 36.3% of men and 46.5% of women visited a doctor when they had an allergic reaction. 40.9% of men and 40.7% of women believed that the allergy was caused mainly by the dust in the house and mites. The other factors, which caused the allergic reaction, were thought to be the specific food and the pollution from cars and factories by men and the specific food and others by women. 35.4% of men and 44.2% of women ate homemade food to prevent allergies.

• Korean Journal of Microbiology
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• v.50 no.2
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• pp.158-163
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• 2014

In the acidic LB plate, a bacterial strain was isolated from homemade soybean paste as a producer of the extracellular mannanase. The isolate YB-1402, which was a Gram-positive rod-shaped bacterium with spore, has been identified as Bacillus amyloliquefaciens on the basis of its 16S rDNA sequence and biochemical properties. Maximum mannanase productivity of the isolate YB-1402 was reached approximately 150 U/ml in LB broth supplemented with konjac (3.0%). The molecular mass of YB-1402 mannanase was estimated to approximately 38.0 kDa by zymogram of the culture filtrate on SDS-PAGE. The mannanase of culture filtrate was the most active at $55^{\circ}C$ and pH 5.5. The mannanase activity was completely maintained after pre-incubation at pH 3.0 to 10.0 for 1 h. The predominant products resulting from the mannanase hydrolysis were mannose, mannobiose and mannotriose for LBG or mannooligosaccharides. The enzyme could hydrolyze mannooligosaccharides larger than mannobiose.