• Korean Security Journal
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• no.13
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• pp.529-550
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• 2007

In proportion to the increase of public security demand, the private companies advanced continuously every year. However the size of the industry expanded in its quantity, the quality remains the same as before. So it's important to training of the security officers. This study suggest the improvements of training system through the analysis and the review of problems of training and education security officers. To develop our private security industry, we suggest as follows. First, In spite of the training is important, the recognition against security officers training is low, so the improvement is demanded. Second, When selecting the educational institution, it does not reflect the demand and situation of education enough. So there is necessary that selecting the educational institution again, after finishing a demonstration duration. Third, The education contents is general, so there is a necessity of the education which is professionalized. Fourth, In order to improve the ability of the lecturer, we must strengthen the qualification of the lecturer. Fifth, For the development of securities industry, we must found the professional training institution.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.2
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• pp.15-29
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• 2020

The aims of this study is to improve physical properties of the sewage sludge and the process sludge generated in the leachate treatment by mixing the dry fuel, to develop the neutral solidifing agents that reduce oder, and to recycle the sewage and the process sludges as landfill cover materials. The mixing ratio (W/W) of sludges and dry fuel was appropriate at about 1:1, and the mixed materials were shown to be homogeneous at that ratio. We could know that when the sludges were mixed with dry fuel, moisture contents and viscosities are reduced, and air passages are formed between particles and particles. The various mixing tests and odor tests showed that the neutral solidifing agent was effective for the odor reduction. The main ingredient of the solidifing agent is the ash of sewage sludge, enabling it competitive in waste recycling and production costs. The landfill cover, using developed neutral solidification agent, improved physical properties to satisfy the quality standards and to increase the compressive strength. It also proved to reduce the value of complex oder and the usage of solidification agent to 1/3 (3,000 to 1,000) and to 1/8 (50% to 6%), respectively, from the comparative study with alkaline solidified landfill cover. Further research is under way to prove that this can be mixed with general soil to be used as a soil improvement agent for plant cultivation.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.389-395
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• 1996

This survey was conducted to investigate the factors affecting the chemical components of groundwater in the plastic house area cultivated with horticulture crops. The data were evaluated with depth of groundwater, topography and years of cultivation as major factors. $NO_3-N$ content of groundwater was higher at waterside(Alluvial plain) than Inland plain(Alluvial plain), local valley & fan or mountain foot area, and also was detected the highest concentration in 6-10m depth well. The contents of $NO_3-N$ and $SO_4{^{2-}}$ in groundwater were increased with cultivation years. The ionic composition (${\sum}A/{\sum}C$ : ratio between total equivalant of anions and cations) of groundwater decreased with depth and was higher at waterside(alluvial plain) than other topography. The $NO_3-N$ content was negatively correlated with pH whereas it was positively correlated with $SO_4{^{2-}}$, $Cl^-$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$.

• Culinary science and hospitality research
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• v.23 no.2
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• pp.159-168
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• 2017

This study was conducted to compare the food quality of domesticated species. Consumers surveyed for safe food intake and proper culture of food distribution. The results of the comparison study are as follows. Muscle moisture content, protein content, and fat content. K, P, and C showed relatively high values in the muscle of the sea bream. Fe showed low contents. As a result of measuring heavy metal component, Cd was not detected in sea bream and mullet, but $0.01{\pm}0.00mg/kg$ was detected in red mine. Other heavy metals were below the reference value or were not detected. Electrophoresis results showed that the band appeared at in red minefish. In the case of sea bream and swordfish, no distinctive features of the band were shown. In the case of sea bream, there was little difference in food science between the similar fish species and the red sea bream fish, but price was different. An environment should be created for consumers to buy the right ingredients at the price they want. It is necessary to educate consumers about food ingredients immediately.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1415-1422
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• 2014

Hot water extraction concentrate was prepared from Alliun hookeri root (AHR) to evaluate its applicability to yogurt. The highest antioxidant activity of hot water concentrates was obtained under extraction conditions of 4 hr at $95^{\circ}C$. Antioxidant activities measured by DPPH radical assay, ABTS radical cation assay, reducing power, and cheating activity were highly correlated with total phenolic (89.51 mg/g) and total flavonoid (52.71 mg/g) contents, with R values of 0.94 and 0.96, respectively. Yogurt was fermented with a commercial lactic acid bacteria mixed strain (Yo-mix$^{TM}$ 305) for 10 hr at $42^{\circ}C$ after addition of 0~10% (w/w) hot water concentrates from AHR to yogurt base. As fermentation proceeded, pH and $^{\circ}Brix$ of yogurt decreased from 6.57~6.60 to 4.34~4.51 and from 8.10~8.90% to 4.60~5.25%, respectively, whereas titrate acidity, viscosity, and viable cell numbers increased from 0.22~0.23% to 1.01~1.10%, from $0mPa{\cdot}s$ to $202.55{\sim}290.50mPa{\cdot}s$, and from 6.40~6.80 log CFU/mL to 8.60~9.20 log CFU/mL, respectively. There was no significant difference in any sensory attribute between the control and 2.5% addition group, suggesting that 2.5% hot water concentrate from AHR could be used to manufacture yogurt.

• Korean Journal of Plant Resources
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• v.8 no.1
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• pp.55-62
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• 1995

This study was carried out to investigate the effects of floral inhibition of Angelica gigas NAKAI in the hilly altitude located in the Northern Gyeongbuk Province from Feb. 1992 to 1994. The results obtained were as follows: As the cultivated areas are high, rate of bolting was significantly decreased, having high yield, good growth, and medicinal quality. It is considered that the optimal cultivating area was at least above 600m altitude. In the hilly altitude, the more shorten nursery period was, the more decreased rate of bolting was, it results in decreased yield, having no significant differences in contents such as extract and decursin. In bolting response from temperature treatment of the seedlings, treatment of temperature was significantly decreased floral induction, but rate of establishment was decreased by decayed root. Bolting rate at different organic resources has more reduced in single fertilization than that of in organic application, but among organic resources, compost of rice straw has the lowest bolting rate. As a result, yield and medicinal qualities at various organic resources were increased in application of organic resources which was no considerable tendency among organic resources.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.3
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• pp.287-293
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• 2009

In this study, red ginseng extract solutions were analyzed to set up the functional saponin content and quality optimization condition. The highest saponin content among the total red ginseng extracts was 64.6 mg / 100 ml which was extracted at $75^{\circ}C$ for 18 hours. In addition, the saponin content decreased according to the increased extraction temperature and time. The highest total content of $Rb_2$ and Re was 11.8 mg / 100 ml at $75^{\circ}C$ for 12 hours which decreased according to the increased extraction temperature and time. The prosapogenin content of red ginseng extract was increased at $75^{\circ}C$ and $85^{\circ}C$ while the content decreased at $95^{\circ}C$, in which the highest prosapogenin content was 34.9 mg / 100 ml at $85^{\circ}C$ for 24 hours. The total sugar content and cloudness were increased according to the increased extraction time at $95^{\circ}C$, but pH and hue value were decreased according to the increased extracted time. The highest sweetness content was 4.0% which was found at $95^{\circ}C$ for 24 hours extract. Therefore, the most appropriate red ginseng extracting method was lower the temperature for saponin content at first time in combination with raise the temperature for taste at second time.

• Tunnel and Underground Space
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• v.29 no.6
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• pp.532-541
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• 2019

Even though shotcrete is a main support for securing the stability of tunnel, the performance of shotcrete is not properly checked due to various difficulties arisen from the characteristics of materials themselves which constitute shotcrete, such as steel fibers and accelerators, and the on-site quality control. In this study, the actual conditions of shotcrete applied to expressway tunnel construction sites were tried to find out, and then some improvement was tried to derive. For this purpose, the characteristics of steel fibers and accelerators supplied to the expressway construction sites were investigated. Also, shotcrete specimens were prepared at the tunnel sites and performance tests were carried out. For steel fiber, domestic production states were investigated, and carbon content and tensile strength were measured using the steel fibers collected in the construction sites. For three types of accelerators such as aluminate, cement mineral and alkali-free, basic properties and total amount of alkali contents were analyzed. Shotcrete specimens were prepared using on-site shotcrete machine with regard to mix designs and types of accelerators. Using these specimens, uniaxial compression tests and flexural tests were performed. As the results, compressive strength, flexural strength, flexural toughness, and etc. were compared with types of acclerators and mix designs.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.419-425
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• 1988

The clarified apple juice was pre-concentrated by reverse osmosis system as a trial for reduction of heat treating time and quality drop in concentration of the juice. The permeate fluxes through CA 865 and CA 960 membranes were higher than those of HR 95 and HR 98 membranes even at the low operating pressure. In the concentration limit depended on the membranes used, HR membranes operated at 60 bar showed $29.0^{\circ}$Brix, and the time required to reach the limit was 86 min for HR 95 and 71 min for HR 98. In cases of CA membranes run at 30 bar, the juice concentration was linearly increased without the limit, and longer time to reach the same concentration was required in comparison with HR membranes. As the juice concentration was increased, the loss of soluble solids was increased, and the average contents of soluble solids in the permeate passed through HR 95, HR 98, CA 865 and CA 960 were 1.3, 0.5, 7.5 and $2.3^{\circ}$ Brix, respectively, in the juice concentration range of 20.0 -$25.0^{\circ}$ Brix. The lower amounts of sugars, total acid and flavor volatiles were involved in the permeate through HR membranes, especially HR 98 than in the permeate through CA membranes.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1120-1127
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• 1998

An attempt was made in this study to investigate the optimum condition of washing for preparation of mackerel surimi by alkaline washing of 1, 3, 5, and 7 times under atmospheric (760), 660, and 560 mmHg pressure. The qualities of surimis were examined by analyzing the factors such as water content, crude lipid, pH, volatile basic nitrogen (VBN), expressible drip, protein extractability, $Mg^{2+}-$, $Ca^{2+}-$ and EDTA-ATPase activity, transglutaminase (TGase) activity, gel strength and color. The contents of moisture, crude lipid, pH and VBN in surimis prepared by alkaline washing under atmospheric, and reduced pressure went up to $72.0{\sim}72.9%$, $4.8{\sim}5.7%$, $6.9{\sim}7.0$ and $6.7{\sim}7.0\;mg/100\;g$, respectively. Protein extractability, ATPase activity and TGase activity were highest in surimis prepared by alkaline washing under 560 mmHg. Gel strengths of surimi setting gel and cooked gel from five times washing under 560 mmHg were 420 g cm (atmospheric, 330 g cm) and 485 g cm (atmospheric, 412 g cm), respectively. For the preparation of mackerel surimi, optimum washing condition was five times washing under 560 mmHg.