• Fire Science and Engineering
• /
• v.32 no.5
• /
• pp.34-39
• /
• 2018

In this study, the experiment conditions for the variation of heat release rate in compartment space were constructed to analyze the effects of fire spread and the operation time of sprinkler in accordance with the heat loss of the sprinkler's heat element. The compartment composed of fire board (width = 0.3 m, height = 0.5 m, length = 3.0 m), are manufactured to measure the temperature distributions in the inner space, the mass loss rate and heat release rate during the experiment of N-heptane pool fire test. Also, the operation time of sprinkler is analyzed with the installation of sprinkler and C-factor using Fire Dynamics Simulator Ver.6 under the experiment conditions. The results show that the operation time of sprinkler, which has RTI $100(m{\cdot}s)^{0.5}$ operating temperature $70^{\circ}C$, is 30 s~60 s for C-factor = 0 and 1, 62 s~92 s for C-factor = 3, and 120 s over for C-factor = 5, respectively.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.7
• /
• pp.1055-1061
• /
• 2014

Innovative freezing technology is currently applied to preserve foodstuffs for long-term storage. Generally, the quality of frozen food is closely related to the types of freezing and thawing processes. In this study, we characterized the physicochemical properties of onions depending on freezing rate. When onions were frozen at $-40^{\circ}C$, freezing rates were 0.1, 0.5, and $0.7^{\circ}C/min$ depending on air-blast quick freezer mode. Onions were thawed by microwave irradiation at 400 W. Hardness of onion dramatically decreased after freezing and thawing compared with blanched onion. However, the fastest freezing rate did not affect hardness. Thawing loss of onion decreased with a faster freezing rate. For morphological observation, onion frozen at a faster rate showed a smaller ice-crystal size. Vitamin C content decreased upon blanching or freezing, but there was no significant difference according to freezing rate. Although free sugar content also decreased upon blanching and freezing, its highest content was at $0.7^{\circ}C/min$ freezing. Among organic acids, malic acid content was highest at $0.7^{\circ}C/min$ freezing. Based on this study, it could be suggested that a faster freezing rate is effective to improve frozen food quality in accordance with preventing tissue damage or minimizing destruction of nutrients.

• Radiation Oncology Journal
• /
• v.14 no.3
• /
• pp.201-209
• /
• 1996

Purpose : To assess the efficacy of high dose rate - intracavitary radio-therapy (HDR-ICR) in the radiotherapy of FIGO stage IB squamous cell carcinoma of uterine cervix and to determine the optimum dose combination scheme of external radiotherapy and ICR to achieve acceptable local control without severe complication. Materials and Methods : One hundred and sixty two patients with FIGO stage Ib squamous cell carcinoma of uterine cervix who received definitive radiotherapy between May 1979 and December 1990 were retrospectively analyzed. All the patients received external radiotherapy combined with HDR-ICR. External dose of 40-46 Gy in 4.5-5 weeks was given to whole pelvis(median 45 Gy) and ICR dose of 30-39 Gy in 10-13 times was given to the point A. Midline shielding was done after 20-45 Gy of external radiotherapy(median 40 Gy) Summation of external dose Plus ICR dose to the point A range were 64.20-95.00 Gy. and mean was 83.94 Gy. We analyzed the local control rate, survival rate, and late complication rate. Rusults : Initial complete response rate was $99.4\%$ for all patients. Overall 5-year survival rate was $91.1\%$ and 5-year disease free survival rate was $90.9\%$. Local failure rate was $4.9\%$ and distant failure rate was $4.3\%$. Tumor size was the only significant prognostic factor. When tumor size greater than 3cm, 5-rear survival rate was $92.6\%$ and less than 3cm, that was $79.6\%$. Late complication rate was $23.5\%$ with $18.5\%$ of rectal complication and $4.9\%$ of bladder complication. Mean rectal dose summation of external midline dose plus ICR rectal point dose was lower in the patients without rectal complication(74.88 Gr) than those with rectal complication (78.87 Gy). Complication rate was increased with low rate of improvement of survival rate when summation of external midline dose plus point A or point R dose by ICR was greater than 70-75 Gy. Conclusion : The definitive radiation therapy using high dose rate ICR in FIGO stage IB uterine cervical cancer is effective treatment modality with good local control and survival rate without severe complication.

• Journal of fish pathology
• /
• v.8 no.1
• /
• pp.23-30
• /
• 1995

We had reported the infection rates of trematode larvae, Cercaria tapidis and C. harengulae in the gonad tissues of Tapes philippinarum and Solen strictus in the estuary of Kum river, the west coast in Korea in 1980~1982. At the same sites from January 1994 to January 1995, we investigated the variation of the infection rates of these trematode larvae in the two clams. The results are follows. The infection rate of C. tapidis parasitized in T. philippinarum increased in 2.4 times (14.0%) higher than that (5.7%) in 1981. Monthly maxium infection rate was 32.0% in October 1994. Comparing the rate (23.3%) in December 1981, the rate in 1994 showed a higher trend than that in 1981. The mean infection rate of C. harengulae in T. philippinarum showed 2.3% in 1994. Comparing that (5%) in 1980, it showed a decreased rate than that in 1980. And monthly maximum infection infection rate of this clam was 6.7% in May 1994, compared with the rate (19.0%) in March 1980. It appeared furthermore decreased rate in 1994. The mean infection rate of the year of C. harengulae in S. strictus was 6.9% in 1994, while it was 10.2% between 1981 and 1982. It showed a decreased trend in 1994. Monthly maximum infection rate was 23.4% in August 1981, while it was 13.3% in April 1994. It showed a decreased trend in 1994 also. In case of C. tapidis the more large sizes of shell length the more infection rates were higher as same in the investigation in 1980, while in C. harengulae the smaller sizes, the more infection rates showed a higher trend.

• Applied Chemistry for Engineering
• /
• v.20 no.4
• /
• pp.423-429
• /
• 2009

The purpose of this study is to investigate the optimal condition for the hydrogen-rich gas production and the CO removal by reforming of gliding arc plasma reforming system using biogas. The parametric screening studies were carried out according to changes of steam feed amount, catalyst bed temperature in water gas reactor and catalyst bed temperature, input air flow rate in preferential oxidation reactor. The standard condition is as follows. The steam/carbon ratio, catalyst bed temperature, total gas flow rate, input electric power and biogas composition rate ($CH_4$ : $CO_2$) were fixed 3, $700^{\circ}C$, 16 L/min, 2.4 kW and 6 : 4, respectively. The results are as follow, HTS optimum operating conditions were S/C ratio of 3 and reactor temperature of $500^{\circ}C$. LTS were S/C ratio of 2.9 and temperature of $300^{\circ}C$. Also, PROX I optimum conditions were input air flow rate of 300 mL/min and reactor temperature of $190^{\circ}C$. PROX II were 200 mL/min and $190^{\circ}C$ respectively. After having passed through each reactor, the results were as follows: 55% of $H_{2}$ yield, 0% of CO selectivity, 99% of $CH_4$ conversion rate, 27% of $CO_2$ conversion rate, respectively.

• Biomedical Science Letters
• /
• v.13 no.3
• /
• pp.213-221
• /
• 2007

This study was designed to investigate the correlation between the expression rate of p53 and p21 proteins, c-erbB-2 oncoprotein and $TGF-{\beta}1$ and tumor prognostic factors in colon cancer including the tumor size, histological differentiation and Dukes' stage. The expression rate of p53 protein was 11.4% (4 cases) at well differentiation, 48.6% (17 cases) at moderately differentiation, and 17.1% (6 cases) at poorly differentiation. In other words, the poorer differentiation, the higher the expression rate of p53 protein (P<0.05). The expression rate of p21 protein was 17.1% (6 cases) at well differentiation, 40.0% (14 cases) at moderately differentiation, and 8.6% (3 cases) at poorly differentiation, indicating that, as the histological malignant degeneration progressed, the expression rate of p21 protein decreased distinctively (P<0.05). However, the correlation of the above mentioned proteins with tumor size and Dukes' stage was not recognized. The expression rate of c-cerbB-2 oncoprotein was 11.4% (4 cases) at well differentiation, 54.3% (19 cases) at moderately differentiation, and 17.1% (6 cases) at poorly differentiation, indicating that the poorer differentiation, the higher expression rate of c-erbB-2 oncoprotein (P<0.05). The expression rate of $TGF-{\beta}1$ was 17.1% (6 cases) at well differentiation, 48.6% (17 cases) at moderately differentiation, and 11.4% (4 cases) at poorly differentiation. As Dukes' stage progressed, the expression rate of $TGF-{\beta}1$ was 8.6% (3 cases) in stage A, 20.0% (7 cases) in stage B, 37.1 % (13 cases) in stage C, and 11.4% (4 cases) in stage D. There was a difference in expression rates between Dukes' stages (P<0.05). In 10 cases, p53 protein was positive while p21 protein was negative, and in 6 cases, p53 protein was negative whereas p21 was positive (P<0.05). Therefore, a statistically significant inverse correlation between the expression rate of p53 protein and that of p21 protein was observed. In conclusion, since there was a signigicant correlation between histological differentiation of colon cancer and the expressions of p53 and p21 proteins and c-erbB-2 oncoprotein, and between Dukes' stage and the expression of $TGF-{\beta}1$, it was conformed that the overexpression of p53 and p21 proteins, c-erbB-2 oncoprotein, and $TGF-{\beta}1$ is closely associated with the occurrence of colon cancer and its progress. Accordingly, this study may be greatly beneficial to the presumption of diagnosis, treatment and prognosis of colon cancer patients.

• Journal of the Korean Ceramic Society
• /
• v.27 no.8
• /
• pp.1055-1063
• /
• 1990

The early hydration characteristics of the system $C_3S-C_3A-C_4AF$ according to the clinker composition variations, in order to establish the mutual interactionof clinker minerals during the portland cement hydration, have been studied. The early hydration rate of $C_3S$ was greatly effected by the change of $C_3S/C_3A$ ratio. The lower the $C_3S/C_3A$ ratio was, the faster the apex reaching time and the rate of heat liberation of the 2nd exothermic peak originating from the formation of $Ca(OH)_2$ were. The effect of $C_3S/C_3A$ ration on the amounts of $Ca(OH)_2$ formation was decreased, in process of hydration time, but the effect of $C_3S$ content was increased.

• Korean Journal of Plant Resources
• /
• v.13 no.1
• /
• pp.29-34
• /
• 2000

In order to obtain fundamental information for developing new salinity tolerance soybean cultivars, the germination rate was evalulated with a total of 28 soybean varieties. The germination rate of soybean cultivars was decreased as the NaCl concentration was higher and that by temperature difference was the lowest at 35$^{\circ}C$. the germination rate of 1.2% NaCl treatment of seed shape and size was the highest at 15$^{\circ}C$ but was the lowest at 35$^{\circ}C$ in small seed groups. The germination rates of Gumjungkong, Alchankong, Gumgangkong, Hayumkong, Hwasungpukong, Janmikong cultivars were higher when treated with 1.2% NaCl at 35$^{\circ}C$, but those of Dawonkong, Hannamkong, Kwangankong, Daebaekkong, Danwonkong, Sukwyangputkong, Keunolkong, Bokwangkong, Jangyoupkong cultivars were lower. The germination rate of soybean cultivars was significantly decreased by higher temperature and NaCl concentration.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.45 no.4
• /
• pp.251-259
• /
• 2009

Swimming crabs, Portunus trituberculatus(Miers) are commercially important off the coasts of Korea, Japan and China. Harvest of swimming crabs has been fluctuated along their distribution ranges. Fluctuations in the interannual harvest of swimming crabs may be correlated with the survival rate during the larval period. The survival rates, intermolt periods, and growth of larval swimming crabs were investigated in the laboratory. Larval swimming crabs are released and undergo development from April to August off the western coast of Korea in the Yellow Sea. Sea surface temperatures off the western coast of Korea during the larval season were used for the laboratory experiments, and ranged from 22 to 26${^{\circ}C}$. Larvae were individually cultured at four different temperatures, 22${^{\circ}C}$, 24${^{\circ}C}$, 26${^{\circ}C}$, and 28${^{\circ}C}$. Zoea molted to megalopa at all temperatures and developed to the first crab stage at 24${^{\circ}C}$, 26${^{\circ}C}$, and 28${^{\circ}C}$. Survival rates from zoea I to the first crab stage increased with increasing temperatures. Intermolt period and the growth rate of the mean carapace length were inversely correlated with temperature. Our research helps understand the changes in survival rate and growth of larval swimming crabs resulting from changing oceanic temperatures. Further, our study suggests that the fluctuations in fishery harvest of swimming crabs off the coast of Korea may be related to changes in larval survival affected by changing ocean conditions.

• The Korean Journal of Physiology
• /
• v.3 no.1
• /
• pp.45-49
• /
• 1969

The effects of water extracts and powder of Korean ginseng on the division of Saccharomyces cerevisiae were studied. 1. The addition of several doses of water extracts and powder of ginseng to the yeast medium of Moyer and Coghill showed various promoted division of Saccharomyces. 2. The optimal dose of ginseng on tile division of Saccharomyces (0.08% dry ginseng medium solution per $10\;cells/mm^3$) could be recognized. 3. On the culture for 24 hours at $18^{\circ}C$, the cell number of control group was $13.25{\times}10^3\;cells/mm^3$ and that of the optimal dose group of water extracts of ginseng was $23.20{\times}10^3\;cells/mm^3$. On the culture, for 24 hours at $25^{\circ}C$, the cell number of control group was $16.85{\times}10^3\;cells/mm^3$ and that of the optimal dose group was $30.20{\times}10^3\;cells/mm^3$. The increasing rate of cell divison by the ginseng was about twice than that of control group. The optimal dose treatment of ginseng at $18^{\circ}C$ was more effective than control group at $25^{\circ}C$. 4. On the culture for 24 hours at $18^{\circ}C$, the increasing rate of water extracts of ginseng was 75.1%, and the rate of ginseng powder was 7.6%. On the culture for 24 hours at $25^{\circ}C$, the rate of water extracts of ginseng was 79.8%, and the rate of ginseng powder was 57.2%. Therefore water extracts of ginseng was more effective than ginseng powder of same dry weight, and the promoted effect of ginseng powder at $25^{\circ}C$ was more effective than at $18^{\circ}C$.