• Journal of Bio-Environment Control
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• v.23 no.1
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• pp.60-64
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• 2014

These studies were conducted to identify the effects of non-perforated breathable package film on storability at $1^{\circ}C$, $8^{\circ}C$, and $20^{\circ}C$ storage of 'Fuji' apples. The fresh weight loss rate was less than 2.0% in all non-perforated breathable films at three different storage periods and temperatures, $1^{\circ}C$; 210 days, $8^{\circ}C$; 75 days, and $20^{\circ}C$; 30 days except for the perforated film. 1,300 cc ($1^{\circ}C$), 5,000 cc ($8^{\circ}C$), and 10,000 cc ($20^{\circ}C$) films were closed at the optimum MA storage condition by carbon dioxide and oxygen concentration. Ethylene concentration was lowest at the 40,000 cc film in every temperatures during storage. The 1,300 cc film established higher result in soluble solid and vitamin C content than any other films at $1^{\circ}C$, also showed higher in visual quality by panel test. The 5,000 cc film had the best results on soluble solid and off-flavor in $8^{\circ}C$. In the $20^{\circ}C$ storage after 30 days of treatment the 10,000 cc film had highest firmness and visual quality. Following these results, it come to conclusion the suitable type of non-perforated breathable film such as 1,300 cc at $1^{\circ}C$, 5,000 cc at $8^{\circ}C$, and 10,000 cc at $20^{\circ}C$ for MA storage in 'Fuji' apples.

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.116-122
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• 2014

This study was conducted to find out the appropriate packaging materials to extend the storability and maintain the quality of cherry tomato for modified atmosphere (MA) storage. Tomatoes were grown by hydroponic at a plastic house in Gangwon Province. Light red maturity stage tomatoes were harvested and packed with MA condition (10,000; 20,000; 40,000; 60,000; 80,000; and $100,000cc/m^2.day.atm$ $O_2$ permeability film) and perforated film to store at $5^{\circ}C$, $11^{\circ}C$ and $24^{\circ}C$. The fresh weight loss was less than 0.6% in all non-perforated breathable films at $^5{\circ}C$, $11^{\circ}C$, and $24^{\circ}C$, but perforated film had less than 2.93% at $5^{\circ}C$, 13.29% at $11^{\circ}C$ and 27.24% at $24^{\circ}C$. The 20,000cc at $5^{\circ}C$ and $11^{\circ}C$, and the 40,000cc film at $24^{\circ}C$ balanced optimum carbon dioxide and oxygen concentration in the package to maintain quality. The 10,000cc film was appeared the significantly highest ethylene concentration at $5^{\circ}C$, $11^{\circ}C$, and $24^{\circ}C$, this film had the lowest $O_2$ permeability. Visual quality, firmness, and soluble solids were maintained in 20,000cc films both at $5^{\circ}C$ and $11^{\circ}C$, the 40,000cc film at $24^{\circ}C$. There was no any trend in titratable acidity and vitamin C content of treated packed film types and temperatures at cherry tomatoes packages. Therefore, the appropriate MA condition for $5^{\circ}C$ and $11^{\circ}C$ is $20,000cc/m^2.day.atm$ $O_2$ permeability film; for $24^{\circ}C$ it is $40,000cc/m^2.day.atm$ $O_2$ permeability film because those films extended the storability through the firmness, soluble solids as well as visual quality.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.1
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• pp.115-123
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• 1990

The purpose of this study was to examine the uses of coal ash as a type of construction material. The methods of examination were chemical anlysis, soil laboratory test and the soil vibration test. Materials used were coal ash obtained as a by-product from 5 thermal power plants in Yongdong, Yongwol, Sochon(anthracite coal) and in Samchonpo and Honam (bituminous coal). Over 70% of the coal ash consisted of silica and alumina. The fly ash grain size showed a uniform distribution from fine-sand to silt, and that of the bottom ash showed from sand to gravel. The specific gravity and density of the coal ash were low. The long term strength increased gradually due to the self-setting property resulting from pozzolanic activity. The shear strength was higher than that of general soil. Cohesion and optimum moisture content of anthracite coal ash were higher than bituminous coal ash, whereas the maximum dry density was higher in bituminous coal ash. The coal ash dynamic Young's modulous curve range was similar to that of general soil. Of the results from the soil vibration test by car-running, the size relative acceleration level in the ash pond was higher than that of natural ground, but the damping ratio was lower than that of natural ground near the ash pond. The coal ash has more advantageous engineering properties than general soil with particles of the same size. For example, the California Bearing Ratio of the bottom ash at both Yongdong and Yongwol was 77~137%. Therefore we expect that if further study is done, coal ash can be used as a construction material when reclaiming seashore, construction embankments, road construction, making right-weight aggregate, or as a general construction material.

• Korean journal of food and cookery science
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• v.22 no.3 s.93
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• pp.291-298
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• 2006

This study, investigated the effect of changes in inoculum levels and fermentation temperature of chunggugjang prepared with Bacillus subtilis(B. subtilis) NRLSI IV on the quality characteristics. In chunggugjang prepared at different inoculum levels, viable cell count, reducing sugar and amino type nitrogen were maximized at $10^6\;CFU/mL$, whereas relative viscosity of viscous substance and hardness peaked at $10^2\;CFU/mL$. In sensory evaluation, chunggugjang made with $10^2\;CFU/mL$ showed higher values of appearance, color, taste and viscosity and a lower value of off-flavor than that made at other inoculum levels. Based on the results of ammonia type nitrogen, relative viscosity and sensory evaluation, the optimum inoculum level for chunggugjang prepared by B. subtilis NRLSI IV was $10^2\;CFU/mL$. In the second step, the effect of different fermentation temperatures on the quality changes of chunggugjang incubated with $10^2\;CFU/mL$ of B. subtilis NRLSI IV were investigated. The viable cell count was maximized at $40^{\circ}C$, but minimized at $45^{\circ}C$. Reducing sugar was not significantly different from $30^{\circ}C$ to $40^{\circ}C$ but was increased at $45^{\circ}C$. Increasing fermentation temperature decreased the content of amino type and ammonia type nitrogen. Chunggugjang prepared at $40^{\circ}C$ showed high sensory evaluation result in microorganism growth, appearance, taste and viscosity and particularly had low off-favor.

• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.120-132
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• 1984

In order to clarify the effect of the fish meat hydrolysate on the growth of lactic acid bacteria(Str. lactis, Str. thermophibus, L. bulgaricus, L. acidophilus, and L. helveticus), the optimum conditions for hydrolyzing the fish meat were examined, and changes of the acid production, viable cell count of lactic acid bacteria and the charge of pH of the culture medium by addition of the fish meat hydrolysate were tested. The results were as follows: 1. When the hydrolysis of back muscle of mackerel was proceeded at $50^{\circ}C$ and at pH 8, for 48 hours adding 6% pancreatin of the protein content in the substrate, the best result was obtained. 2. The composition of the fish meat hydrolysate were 53.6% moisture, 32.4% protein, 1.0% fat, 10.7% carbohydrate, and 3.2% ash. 3. Above 0.1% of the fish meat hydrolysate in the culture medium, the acidity of the culture medium by Sir. lactis and Str. thermophilus were increased remarkably. The acidity of the culture medium by L. acidophilus and L. helveticus were increased in above 0.2% fish meat hydrolysate in the culture medium. but L. bulgaricus was not effected by the fish meat hydrolysate. 4. The pH of the culture medium during incubating Str. laclis and Sir. thermophilus failed obviously by adding the fish meat hydrolysate. But in the cases of L. bulgaricus, L. acidophilus, and L. helveticus, the pH were not changed clearly. 5. The viable cell count in all bacterial strains tested here were elevated by increasing the concentration of the fish meat hydrolysate.

• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.309-317
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• 1987

The raw milk produced in Korea was heated at $70^{\circ}C$, $75^{\circ}C$, $80^{\circ}C$, $85^{\circ}C$, $90^{\circ}C$, $95^{\circ}C$ and $100^{\circ}C/15sec.$. The changes in chemical composition and microbiological aspects of the milk were summarized as following results: 1. In high temperature pasteurized milks as the heat treatment increased, pH value decreased but protein, fat, lactose and ash did not show significant changes in their contents while casein nitrogen and non-protein nitrogen increased but non-casein nitrogen and filterable nitrogen decreased in their contents. 2. Calcium content of raw milk decreased from 119.79mg/100g to 111.86mg/100g at $75^{\circ}C$ and to 106.24mg/100g at $100^{\circ}C$. Vitamin C decreased from $1.37mg/100m{\ell}$ of raw milk to $1.15mg/100m{\ell}$ at $75^{\circ}C$ and $0.94mg/100m{\ell}$ at $100^{\circ}C$. Artificial digestibility increased as the heat treatment got higher. 3. Viable bacteria counts decreased from $9.0{\times}10^3/m{\ell}$ at $75^{\circ}C$ to $3.4{\times}10^2/m{\ell}$ at $100^{\circ}C$. Coliforms were not found at $70^{\circ}C$ and thermoduric bacteria, thermophiles, psychrotrophic bacteria, mould and yeast decreased rapidly as the heat treatment increased. 4. The results of Keeping quality test for high temperature pasteurized milk showed that the' milks preserved at $25^{\circ}C$ and $37^{\circ}C$ were clotted just after 1 day but the milk preserved at $4^{\circ}C$ showed good shelf life which did not have any deterioration in titratable acidity, microorganisms and com positions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.6
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• pp.747-756
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• 1995

To find out the optimum application method of slow-releasing fertilizer(SRF) and conventional fertilizer(CF) with different fertilization rate under two culture methods[l0-day old seedling machine transplanting(MT) and direct-sowing on dry paddy(DS)] in the south-western region(clay loam soil) of Korea, used were Chosun slow-releasing fertilizer(silicate latex coated fertilizer: N-P$_2$O$_{5}$-K$_2$O =18-12-13) and conventional fertilizer. Plant height and number of tillers with different two culture methods were higher at MT than DS in early growth. The ratio of dry weight in heading stage was higher at CF than SRF in MT than DS and especially, SRF 80% + CF 20% than SRF 100% or CF 100%. Leaf area index (LAI) in heading stage was higher at CF in MT but higher at SRF in DS than their counterparts. Chlorophyll content was higher at SRF than in CF expect for heading stage(HS), especially in DS. It was highest at HS in CF without its difference during maximum tillering stage(MTS) and panicle formation stage(PFS), while highest at PFS in SRF with tendency of gradual increase and decrease before and after PFS, respectively. Heading was delayed 2~3 days at SRF in two cultrue methods and 4~5 days at SRF in DS in comparison with CF in MT with delay of 2 days at DS compared with MT. Culm length was longer at CF in MT and at SRF in DS than their counterparts. Panicle number per m was more at SRF and in DS. Filled grain ratio was higher at CF and in MT. Yield was obtained 101 and 100% at 100% and 80% level of SRF in DS respectively, and 96% at 80% level of CF in MT, compared with conventional application method (516kg /l0a), and increased 2~4% at DS and 0~3% at MT in SRF. Yield was high in order of 100%(SRF) =80%(SRF) + 20%(CF) > 100%(SRF) + 20%(CF) > 80%(SRF) at MT and 80%(SRF) + 20%(CF) =100%(SRF) > 80%(SRF) =100%(SRF) + 20%(CF) at DS.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.387-394
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• 2012

The study was conducted to develop an effective forest resources use models for an alternate use of abandoned quarry by an attitude survey. According to the result of survey, a pessimistic view due to dust, noise pollution, and forest damage was 5% higher than an affirmative view by economic benefits from the development of quarry. The 42% of the respondents preferred the alternate use of abandoned quarry and the 25% of the respondents wanted an art and cultural space. The optimum size of alternate use was 5-10 ha (43%) with the requirement of nearby residents (32%). According to the SWOT analysis for abandoned quarry, the strength factors were an effective use of land, the content development of modern industrial inheritance + cultural and art fusion, attraction for nearby city and visitors, a harmony of beauty landscape and clean environment, and a sustainable increase of domestic and foreign visitors with the 5-day-work week. The opportunity factors were the improvement of traffic networks through KTX and local highway, the creation of the new growth engines with the establishment of artistic creation belts, the providing of unique cultural and art space through grafting of tour and education, the creation of local income through stone processed goods, and the vitalization of local development through eco-city. The weakness factors were a psychological remoteness and backwardness, and the weakness of staying tour infra. The threat factors were a poor financial support for sustainable development in nearby quarry and a modify of legal and institutional system for the alternated use of abandoned quarry. The developed restoration models for the alternate use in abandoned quarry are classified to a sculpture park, a waterfall and lake park, a rock-climbing, a sports park + forest park, a native botanical garden, a culture and art park, a complex park, a water storage site, a water storage site to extinguish forest fire, a geriatric hospital, an agricultural facility, and a school site types etc. The results suggest that the alternate use in the abandoned soil and stone quarry is needed to establish facility use models with consideration of user's preference.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.718-724
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• 1999

This study was investigated the changes of the properties of matter such as the gel formation of the combined fish based on the mixed rate between the ocean jumbo squid and Alaska pollock surimi, and compared the relationships between the gel formation and water holding capacity. The changes of the gel formation based on 20 min fish grinding time and $2.5\%$ salt concentration according to the mixed rate was thought as the optimal addition limit. There was no significant function of gel product more than $20\%$ Jumbo squid meat. The more squid meat in the mixed meat could make the lower breaking stress but 7:3 rate of pollock : squid could retain breaking strain. The effect of the moisture content on mixed fish meat was studied and the drastic decrease of the gel formation and water holding capacity was indicated in $78\%$.

• Journal of the Korean Electrochemical Society
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• v.9 no.4
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• pp.141-150
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• 2006

Nanocrystalline CoW thin/thick film alloys were electodeposited from citrate baths to investigate the influences of metal ion concentration, current density and solution pH on chemical composition, current efficiency, residual stress, surface morphology, and microstructure of the film. Deposit W (tungsten) content in CoW thin/thick film increased with increasing W ion concentration, current density, and solution pH in the plating bath. It was observed that residual stress in CoW thin/thick film decreased with increasing W ion concentration and solution pH. CoW thin film exhibited mixed phases of hop Co [(100) and (002)] and hcp $Co_3W$ [(002) and (201)] at W ion concentration with 0.02 to 0.08 M. The microstructure of CoW thin film at W ion concentration of 0.1 to 0.2 M was close to amorphous phase. The dominant phases were found to be hop Co (002) and hop $Co_3W$ [(200), (002) and (201)] at the current densities of 5, 10, 25, and $100mA{\cdot}cm^{-2}$ CoW thin film at the current densities of 50 and $75mA{\cdot}cm^{-2}$ was close to amorphous phase. At solution pH 8.7, CoW thin film exhibited hcp Co (002) and hop $Co_3W$ [(200), (002) and (201)]. Below solution pH 8.7, CoW thin film exhibited amorphous microstructure. The optimum electrodeposition conditions for CoW thin/thick film were found to be W ion concentration of 0.08 M, current density of $10mA{\cdot}cm^{-2}$, and solution pH 8.7.