• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.3
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• pp.127-137
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• 2022

Zirconia is fabricated through various processes. Each element in fabricating process can affect the physical properties of the definitive prosthesis. In particular, both the milling process and the sintering process can affect the final integrity of the zirconia prosthesis. Most of the milling machines adopt the ultra-precision 5-axis machining method, and the results vary depending on which milling method was used and how the milling equipment was managed. Milling blocks are selected according to cutting efficiency and aesthetic reproducibility. The sintering method can affect the grain growth and optical properties, and an accurate evaluation can be made only with additional research on the recent speed sintering procedure. Not only the sintering temperature but also the temperature holding time can affect the quality of definitive prosthesis.

• The Journal of Engineering Geology
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• v.33 no.3
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• pp.427-438
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• 2023

We carried out a geological survey to classify the types of mass movement in Danyang Geopark (where various rock types are distributed) and analyzed the mechanical and hydraulic characteristics of landslide materials using a series of laboratory tests. Debris flows occurred in areas of limestone/marble, shale, and porphyroblastic gneiss, and limestone/marble landslides were distinguished from the others through the presence of karren topography. Soil tests showed that soil derived from weathered gneiss, which has a higher proportion of coarse grains, has a higher friction angle, lower cohesion, and larger hydraulic conductivity than soils from areas of limestone/marble, and shale. Rock failure mass movements occurred in areas of phyllite, sandstone, and conglomerate and were subdivided into plane failure, block-fall, and boulder-fall types in areas of phyllite, sandstone, and conglomerate, respectively. The shear strength of phyllite is much lower than that of the other types of rock, which have similar rock quality. The slake durability index of the conglomerate is similar to that of the other rock types, which have similar degrees of weathering, but differential weathering of the matrix and clasts was clearly observed when comparing the samples before and after the test. This study can help establish appropriate reinforcement and disaster prevention measures, which depend on the type of mass movement expected given the geological characteristics of an area.

• Journal of Powder Materials
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• v.31 no.2
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• pp.169-179
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• 2024

Colloidal quantum dot (QDs) have emerged as a crucial building block for LEDs due to their size-tunable emission wavelength, narrow spectral line width, and high quantum efficiency. Tremendous efforts have been dedicated to improving the performance of quantum dot light-emitting diodes (QLEDs) in the past decade, primarily focusing on optimization of device architectures and synthetic procedures for high quality QDs. However, despite these efforts, the commercialization of QLEDs has yet to be realized due to the absence of suitable large-scale patterning technologies for high-resolution devices., This review will focus on the development trends associated with transfer printing, photolithography, and inkjet printing, and aims to provide a brief overview of the fabricated QLED devices. The advancement of various quantum dot patterning methods will lead to the development of not only QLED devices but also solar cells, quantum communication, and quantum computers.

• Journal of the Korean Recycled Construction Resources Institute
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• v.12 no.2
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• pp.229-238
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• 2024

This study evaluated the odor removal performance of a bacteria-based odor reduction kit. The bacteria used were Rhodobacter capsulatus, Paracoccus limosus, and Brevibacterium hankyongi, which can remove ammonia (NH₃), hydrogen sulfide (H₂S), total nitrogen (T-P), and total phosphorus (T-N), which are odor pollutants. The materials used were bacteria and porous aggregates (expanded vermiculite, zeolite beads, activated carbon), and the combination of the materials varied depending on the removal mechanism. Materials with a physical adsorption mechanism (zeolite beads and activated carbon) gradually slowed down the concentration reduction rate of odor pollutants (NH₃, H₂S, T-P, and T-N), and had no further effect on reducing the concentration of odor pollutants after 60 hours. Expanded vermiculite, in which bacteria that remove odors through a bio-adsorption mechanism were immobilized, had a continuous decrease in concentration, and the concentration of odor pollutants reached 0 ppm after 108 hours. As a result, the odor removal performance of materials with physical adsorption mechanisms in actual river water did not meet the odor emission standard required by the Ministry of Environment, while the expanded vermiculite immobilized with bacteria satisfied the odor emission permissible standard and achieved water quality grade 1.

• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.513-520
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• 2023

Korean melon (Cucumis melo L.) is an environment in which most farming work can affect the increase in musculoskeletal diseases, and the stems are attracted to the ground in order to grow no-heating cultivation. In this study, growth and productivity were compared according to the type of high-bed. The narrower the surface area at the bottom of the high-bed, the faster the initial growth, which was advantageous. The bed is which the height if 70 cm, the surface temperature has risen due to the increase in direct solar radiation inflow since April, requiring side light blocking to block the inflow of solar radiation. In terms of fruit quality, the 200 cm width treatment had higher fruit sugar content and better hardness than the 160 cm treatment. From April to September, the total yield was 6.8 kg/plant of treatment A, 8.7 kg/plant of treatment B, 5.8 kg/plant of treatment C, treatment B mainly 50% higher than treatment C, and 27% higher than treatment A. Therefore, the bed form suitable for Korean melon high bed is 200 cm wide, 40 cm high between the surface and the bed, and the surface of the passage between the beds is 30cm high from the ground to the bed.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.1
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• pp.41-48
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• 1999

This experiment was carried out to determine the effect of the silage additives on improvement of quality of fresh rice straw silage using round bale at the forage experimental field, grassland and forage crops division, National Livestock Research Institute, RDA, Suwon from 1997 to 1998. The experiment was arranged in a randomized block design with three replication. The treatments used in this study were consisted of different additives(control, formic acid, molasses, molasses+urea and inoculant). The rice straw silage with molasses+urea treatment resulted in high crude protein content and in vitro dry matter digestibility were increased with molasses of inoculant treatments compare with the control. The mean dry matter of formic acid treatment material was higher than with control but there was no significant difference in dry matter content among the additives treatments. The pH of molasses treatments significantly increased the proportion of lactic acid(P<0.05) and decreased the proportion of butyric acid. The total organic acid content of all treatments had low around 2%. Ammonia-N of molasses+urea treatment was significantly(P<0.05) higher than that of others, but formic acid or inoculant treatments was lower below 10% per total nitrogen. Over a 7d feeding period, the dry matter intake per cattle on the inoculant treatment was higher that on both the untreated round bale silage of fresh rice straw and rice straw hay. Producing cost per kilogram of round bale silage of fresh rice straw was decreased according to the increasement of harvesting area. It is suggested that application of round bale silage system to fresh rice straw with molasses or inoculant was the best treatment for improving preservation as silage, and that animal intake was enhanced by addition of inoculant to fresh rice straw.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.2
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• pp.127-134
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• 2010

A study was conducted to determine the effects the of cattle manure application on forage yield, quality and soil in orchard grass pasture at the experimental field of Subtropical Animal Experiment Station, National Institute of Animal Science from 2008 to 2009. The experiment was arranged in a randomized complete block design with three replications. The treatment consisted of chemical fertilizer (CF N-200 kg/ha), cattle manure 50% (basis N, CM50%), CM100% (basis N), CM200% (basis N). The dry matter (DM) yield of CM200% was the highest among the other treatments. CF showed the highest average crude protein (CP) content by 12.4% and CM50% showed the lowest content by 11.0%. Average acid detergent fiber (ADF) and neutral detergent fiber (NDF) content were 30.4 and 69.7% respectively. All treatments have narrow range of total digestibility nutrient (TDN) from 64.0% to 69.1%. But there were big difference between treatment in forage nitrate content. Changes of physical and chemical properties of soils for applications of CF 200% and CM 200% was clearly in cattle manure application. Especially, CM application in pasture increased CF application with respect to soil pH, organic matter (OM), and avaliable phosphorous ($P_2O_5$) contents of soils.

• Korean Journal of Soil Science and Fertilizer
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• v.2 no.1
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• pp.31-38
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• 1969

This experiment was carried out to determine the effect of different levels of phosphate and potash firtilizers applied on yields and quality of leaf tobacco. It was done at all varying levels of phosphate and potassium fertilizers $S_0$ (non-fertilizer plot);N:P:K=0:0:0 (Kg/10a) $S_1$ (1/2 amount plot);N:P:K=10:7.5:10 (Kg/10a) $S_2$ (standard plot);N:P:K=10:15:20 (Kg/10a) $S_3$ (1.5 times plot);N:P:K=10:22.5:30(Kg/10a) $S_4$ (2.0times plot);N:P:K==10:30:40 (Kg/10a) Urea was applied as nitrogen, triple superphosphate as phosphate, potassium sulfate as potash source. The total amount of fertilizers was applied as basal dressing per one plant. This experiment was carried out by using randomized block design with 3 replication. The results obtained in terms of yields and quality are summarized as follows. 1. By increasing the amounts of phosphate and potassium fertilizers, growing status of the largest leaf length, the largest leaf width and stem size of tobacco increased in the order of $S_4>S_3>S_2>S_1>S_0$. 2. By increasing the amount of phosphate and potassium fertilizers, yield was increased in the order of $S_4>S_3>S_2>S_1>S_0$, This increase showed generally high significance among various levels of treatments. 3. The regressive equation was derived from the relationship between treatment levels and tobacco leaf yield. The most desirable treatment level for the maximum yield was estimated as the 2.87 times as much as the treatment level of phosphate and potasium fertilizers of standard plot. 4. By increased application of phosphate and potash fertilizers, the contents of $P_2O_5$ and $K_2O$ in the tobacco leaf became greater while the content of nicotine was decreased. Thus, a negative correlation between fertilizer application and nicotine content has been observed.

• Korean Journal of Poultry Science
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• v.42 no.2
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• pp.181-189
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• 2015

The objective of this study was to investigate the effect of dietary supplementation of vitamin C and Sea buckthorn on the performance, blood biochemistry and meat quality in old laying hens. A total 200 Hy-Line Brown laying hens (101 weeks old) were randomly allotted to 1 of 5 dietary treatments : (1) Basal : basal diet, (2) Vit. C : basal diet + 0.1% vitamin C, (3) SB 0.1 : basal diet + 0.1% Sea buckthorn, (4) SB 0.5 : basal diet + 0.5% Sea buckthorn, and (5) SB 1.0 : basal diet + 1.0% Sea buckthorn. Each treatment was replicated 4 times with 10 birds units were arranged according to randomized block design. Feeding trial lasted 4 weeks under 16L:8D lighting regimen. The diets were fed to hens on an ad libitum basis for 4 weeks. Result indicated that during feeding trial of the experiment, hen-day egg production and feed conversion ratio were not significantly influenced by treatments. However, feed intake was significantly (P<0.05) higher in Vit. C and SB treated groups than the basal during 1 wks and 3 wks. Egg weight was significantly (P<0.05) higher in basal and Vit. C than the SB 1.0 treatment. There were no differences in carcass yield during feeding trials. However, partial ratio (breast and neck) was significantly (P<0.05) higher in SB 0.5 than other treatment. There were no differences in the level of leukocytes and erythrocytes. There were no significant differences on proximate analysis (DM, crude protein, crude fat, and crude ash), meat color, water holding capacity, cooking loss, and fatty acids concentrations. In conclusion, dietary supplementation of vitamin C and Sea buckthorn to the diet of old laying hens might be a potential ingredient for increasing partial weight (breast) in old laying hens.

• Korean Journal of Organic Agriculture
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• v.21 no.1
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• pp.79-93
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• 2013

The experiment was conducted to investigate the effects of feeding herbaceous peat on growth performance and meat quality of Holstein beef cattle. Total of 20 Holstein beef cattle (18~20 month of age, $657{\pm}31kg$ body weight) were conventionally and separately fed a concentrate diet and rice straw for 134 days. The dietary treatments were randomly assigned by complete block design into four treatments, each of which were five heads in early fattening stage. The treatments in this study were the control group fed basal diet, feeding herbaceous peat group (5%/diet, T1), feeding coated vitamin C group (20g/head, T2) and feeding mixture of herbaceous peat and coated vitamin C group (5%/diet+20g/head, T3). The initial body weights between the groups of control, T1, T2 and T3 were similar showing with $689{\pm}31$, $661{\pm}24$, $659{\pm}32$ and $622{\pm}19kg$. The daily body weight gain was higher in T3 by 8.3% than that in the control (p<0.05). Glucose concentration in control group was the highest among treatments (p<0.05), but there was no significant differences between treatments on AST (aspartate aminotransferase), ALT (alanine aminotransferase), BUN and total protein concentrations of blood. The fat content of sirloin in the T2 was significantly higher than control and T1 group (p<0.05). Meat color (CIE) values in T2 was the highest among treatments (p<0.05), and other treatments also increased those values. In overall, the feeding herbaceous peat and vitamin C to the Holstein beef cattle was considered to have positive effects on the growth performance of Holstein beef cattle. In addition, the effects on the performances of animals were more improved when fed herbaceous peat and vitamin C concurrently.