• Journal of the Korean Geotechnical Society
• /
• v.15 no.6
• /
• pp.307-317
• /
• 1999

The purpose of this study is to utilize conventional procedures for evaluation of liquefaction potential and to compare the results obtained by modified detailed method based on Korean earthquake magnitude (M=6.5). Liquefaction potential is assessed by comparing liquefaction strength of soil and cyclic shear stress generated in the soil layers during earthquakes. The cyclic shear stress is computed from the earthquake response analysis, and liquefaction strength of soil is evaluated by using results from cyclic triaxial tests. The cyclic triaxial tests are performed on many different conditions of sample ; relative densities(50%, 60%, and 70%), initial effective confining pressures (70kPa, 100kPa, and 150kPa), and fine contents(10%, 20%, and 30%). From the result of comparing the conventional procedure with the modified detailed method, it is found that the modified detailed method tends to evaluate larger safety factor against liquefaction in the weak sand site$(FS \leq1.5)$. Therefore in this case, it is suggested that liquefaction potential should be evaluated by using the modified detailed method based on cyclic triaxial tests. It is also found that in modified detailed method based on earthquake magnitude 6.5, critical depth where liquefaction can be generated is around 15m from the ground surface.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.36 no.11
• /
• pp.1417-1424
• /
• 2007

The food components of fish (skipjack tuna, yellowfin tuna, bluefin tuna, conger eel, salmon, Spanish mackerel, armored weasel-fish) frames and their hot-water extracts were investigated to explore their possibilities as resources for fish Gomatang. According to the results of volatile basic nitrogen and heavy metal, bluefin tuna and salmon frames were below the safety limits suggested by Codex Code. Thus, bluefin tuna and salmon frames appeared to be safe as basic ingredients for fish Gomtang. The major components of all hot-water extracts from fish frames were nitrogenous component. According to the results of extractive nitrogen and sensory evaluations of hot-water extracts from fish frames, the salmon frame was a good raw material as a basic ingredient of fish Gomtang. The calcium and phosphorus contents of hot-water extracts from salmon frame were 18.0 mg/100mL and 33.1 mg/100mL, respectively.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.6
• /
• pp.859-863
• /
• 2010

The principal objective of this study was to compare and analyze the qualitative characteristics of mulberry leaf tea (MLT) and fermented mulberry leaf tea (FMLT). The concentrations of polyphenols were approximate in FMLT and MLT, with measurements of 4,022.82 mg/100 g and 3,932.32 mg/100 g, respectively. These polyphenol concentrations were relatively high and were approximate to the contents in green tea and yellow tea. Moreover, both MLT and FMLT contained small amount of vitamin C. The concentrations of caffeine were also relatively low for both MLT and FMLT, with values of 5.68 mg/100 g and 21.11 mg/100 g, respectively. When the quality of the MLT and FMLT was evaluated, we noted only minimal difference in color a (redness) values between each material; however, the b (yellowness) and the L (lightness) values were higher in the MLT than in the FMLT. When sensory tests were conducted, both materials were judged to have a bitter taste, and FMLT has a synthetic and pleasant taste.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.42 no.1
• /
• pp.83-88
• /
• 2013

To improve kimchi qualities, Ecklonia (E.) cava of 5%, 15% or 25% were added and the qualities investigated by measuring changes in physicochemical, microbiological, and sensory characteristics during fermentation at $5^{\circ}C$. The pH of kimchi with E. cava added decreased and acidity increased. The number of Leuconostoc sp. in kimchi reached its maximum at the optimum fermenting stage, the $16^{th}$ day in control kimchi and the $20^{th}$ day in the kimchi added E. cava. The optimum fermenting stage of the kimchi was retarded due to adding the E. cava. The reducing sugar contents was highest in kimchi with 25% E. cava during the early stage of fermentation. According to Hunter's color values, the lightness of the kimchi with E. cava added decreased during fermentation, while the redness increased as fermentation proceeded. The sensory scores for overall acceptance, taste, texture and appearance were highest in kimchi with 15% E. cava.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.42 no.12
• /
• pp.2004-2011
• /
• 2013

This study was carried out to investigate the chemical and microbiological properties of Kimchi containing different amounts of squid and octopus during fermentation at $4^{\circ}C$ for 56 days. Kimchi were assigned to one the of the following 7 treatment groups: CK (control Kimchi; no addition), SK-5 (added 5% of squid), SK-10 (added 10% of squid), SK-20 (added 20% of squid), OK-5 (added 5% of octopus), OK-10 (added 10% of octopus), and OK-20 (added 20% of octopus). The quality characteristics of CK and other treatments were determined by measuring the pH, titratable acidity, reducing sugar, volatile basic nitrogen (VBN), and microbial analysis. During fermentation, Kimchi containing squid and octopus had higher pH and lower acidity values than the CK group (P<0.05). The titratable acidity was increased in all treatment groups, whereas the reducing sugar content decreased gradually during fermentation. The reducing sugar contents were highest in the CK group. The VBN value increased in all treatment groups with increasing storage period, and the CK group had lower VBN value than the other treatment groups containing squid and octopus. The numbers of total bacteria and lactic acid bacteria rapidly increased up to the second week, and this slowly increased thereafter.

• Economic and Environmental Geology
• /
• v.46 no.5
• /
• pp.469-476
• /
• 2013

With the advent of a new Korean government, a new national agenda (140 items) was reported. Additionally, Work Plans of the executive bodies were also released, including the Ministry of Science, ICT and Future Planning (MSIP); the Ministry of Trade, Industry and Energy (MOTIE); the Ministry of Oceans and Fisheries (MOF); and the Ministry of Environment (MOE); the Ministry of Land, Infrastructure, and Transport (MOLIT). For government-supported research institutes, it will be important to watch and analyze the changes in the government's primary policies and strategic goals. In this paper, we analyzed new governmental research and development (R&D) policy with respect to geoscience and mineral resources technology. The results indicated that the executive bodies emphasized, for the job creating 'creative economy' and the 'safety and integration society', the establishment of the creative economy; science and technology development based on creativity and innovation; creation of new growth engines by fusion and diffusion; construction of stable energy systems; promotion of environmental industry; and creating satisfactory land services. In the area of geoscience and mineral resources technology, it is time to search for a new, creative, and interagency fusion R&D contents to meet the needs of the public and boost its national competitiveness.

• Korean Journal of Food Science and Technology
• /
• v.43 no.1
• /
• pp.98-104
• /
• 2011

The storage quality of fresh buckwheat sprouts, as influenced by pretreatment and packaging within processing steps, was investigated to establish appropriate postharvest handling treatment for the commodity. After harvest, the sprouts were dipped in chlorine water (100 ppm), rinsed twice with clean water, pre-cooled with iced water, de-watered, and packed in plastic trays. Sprout samples taken from each processing step were stored at $5^{\circ}C$ for 6 days to measure quality attributes. Viable cell counts of mesophilic aerobes and coliform bacteria were lower by about 1 log scale in the postharvest treated samples compared to an untreated control, although the initial microbial reduction due to the postharvest treatments was offset by cell growth during storage. All sprout samples showed a decrease of fresh weight by approximately 4% after 6 days of storage. However, moisture and soluble solid contents were maintained at the initial levels of the sprouts. No significant difference in surface color was observed among sample treatments. For sensory properties including discoloration, wilting, decay, and visual quality, there were no significant differences among sample treatments. The present results suggest that proper postharvest processing treatments can exert positive effects on extending the shelf-life of fresh buckwheat sprout.

• Korean Journal of Food Science and Technology
• /
• v.37 no.3
• /
• pp.397-404
• /
• 2005

Effects of ${\gamma}$-oryzanol (0.0, 0.1, 0.5, 1.0, 2.0%) addition on physical and chemical properties of yackwa were determined during storage for 6 weeks at $30^{\circ}C$. Acid, peroxide, and thiobarbituric acid (TBA) valves, color, texture, fatty acid compositions, hexanal content, and rancid flavor of yackwa were measured. Acid, peroxide, and TBA values. and hexanal contents of ${\gamma}$-oryzanol-treated groups were significantly lower than those of groups without ${\gamma}$-oryzanol treatment after 6 week (p < 0,05) and showed concentration-dependency, while no significant differences were observed in colors (p > 0.05). Effects of ${\gamma}$-oryzanol on textural characteristics were not consistent. As storage time increased, ratio of unsaturated fatty acids to saturated fatty acids or ${\gamma}$-oryzanol-added groups was higher than that of groups without ${\gamma}$-oryzanol addition. Addition of ${\gamma}$-oryzanol was effective in decreasing hexanal formation. Sensory evaluation showed rancid odor decreased with increasing concentration of ${\gamma}$-oryzanol. These results suggested ${\gamma}$y-oryzanol, as a natural antioxidant, delayed quality decrease of yackwa during storage.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.10
• /
• pp.3911-3916
• /
• 2010

In this paper we describe contents and results on running test for ATP on-board equipment, which has propelled as one of the research projects, so called, "Reliability assessment and operation technology development for Korean-type tilting trains" in order to ensure the safety and operation efficiency of tilting trains. We developed tilting trains for the speed-up of conventional lines and for the passenger service improvement where the KTX is not available. And we made progress the operation trial test in the 120,000 km distance with the use of ATS equipment, used in existing lines, for the purpose of the reliability assessment of the developed tilting trains. We decided to accelerate the speed for more than 200km/h with respect to the 6 existing lines including Jungang-line and Chungbuk-line where KTX has not operated. According to this decision, Train control system is to be changed from ATS to ATP. We should have installed an ATP on-board unit in tilting trains and verified the operational suitability, therefore we installed the same ATP on-board unit on tilting trains as that used in the ATP construction project on Gyeongbu-line and Honam-line, and verified that the function and performance of the installed ATP on-board unit conformed to the tilting trains operation.

• Journal of Environmental Health Sciences
• /
• v.41 no.1
• /
• pp.1-10
• /
• 2015

Objectives: The purpose of this study was to propose an indirect exposure assessment method using a questionnaire survey at a time when direct exposure assessment would be impossible after a chemical accident. Methods: About two weeks after an accident, a questionnaire survey was performed with 1,264 persons from the local community. Variables related to exposure were extracted from the survey contents, weighted and then graded for comparison with subjective symptoms in order to evaluate the extent of exposure. Survey items suitable for reflecting the previous exposure level during the accident were extracted, weighted and divided into quartile ranges. Subjective symptoms showed an increasing tendency with higher exposure level when compared with final exposure level (p<0.01). Results: For the relationship between the final exposure grade and subjective symptoms, as the exposure grade was increasing the rates complaining of symptom also showed an increasing tendency. However, when adjusted for demographic characteristics, there was a tendency for the eye irritation symptom to appear higher in women, and respiratory organ irritation appeared higher in smokers. Conclusions: When the problem of recall bias is considered, this study may not have completely unraveled exposure and the characteristics of the participants can affect subjective symptoms. Nevertheless, the exposure rating method of using a questionnaire showed a significant relationship with symptom level. It can be deemed that assessment of past exposure may be successfully evaluated by questionnaire in cases such as chemical accidents.