• The Journal of the Acoustical Society of Korea
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• 제25권1호
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• pp.7-13
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• 2006

Fisheries policy change from catching to farming requires more intensive consideration for aquaculture industry. The oceanic farm is a desirable cost effective aquaculture method. However. in odor to gather fish in the oceanic farm, eating sound or any attracting sound should be radiated through underwater loudspeaker. In this Paper, it has been found in literature that the frequency range responding to fish is about 16Hz to 13kHz but sensitive frequency range is about 150Hz to 2kHz and sound pressure level is about 100dB to 150dB reference $1{\mu}Pa$. Therefore, frequency range and output sound level of designed underwater loudspeaker has been specified as 150Hz to 3kHz and 100dB to 145dB reference $1{\mu}bar$. respectively To verify the stability and the endurance to the pressure of 40m water depth, manufactured underwater loudspeaker was examined before sea trial in manufactured water pressure tank which gives a maximum of 10 atmospheric Pressure. We experimented on acoustic characteristic with manufactured underwater loudspeaker under water depth of 10m.

• Korean Journal of Environmental Agriculture
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• 제40권4호
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• pp.279-289
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• 2021

BACKGROUND: Recently, the golden apple snail, Pomacea canaliculata has been used as an environmentally-friendly weed-control agent in rice farming. Although effective for this particular style of farming, P. canaliculata can be destructive to other crops. The objective of this study was to identify overwintering as well as regional and seasonal distribution characteristics of P. canaliculata. Notably, winter is typically fatal for P. canaliculata. However, owing to increasing average global temperatures, we assessed the ability of P. canaliculata to survive through uncharacteristically warm winters. METHODS AND RESULTS: To examine the distribution and overwintering regions of P. canaliculata, We conducted a survey from April 2020 to May 2021 on environmentally-friendly rice fields, agricultural waterways, and streams in 23 cities belonging to 8 provinces. In addition, because air temperature may influence the distribution density of P. canaliculata, we analyzed the winter temperature data (http://weather.rda.go.kr). CONCLUSION(S): In 2021, overwintering of P. canaliculata (1-3 individuals/m²) was observed in the Goheung and Yeongam regions in Jeonnam. Overwintering of P. canaliculata was observed in fewer regions in 2021 than in 2020; this fact may be attributed to the lower minimum temperatures measured in 2021 (approximately 8℃ lower) than those in 2020. Our results suggest that overwintering occurs as long as overnight temperatures are ≥ -15℃, but can take place if temperatures are as low as -19℃.

• Journal of Environmental Science International
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• 제28권1호
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• pp.7-18
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• 2019

This study aimed to assess the impact of livestock excreta discharged from an Intensive Livestock Farming Area (ILFA) on river water quality during a rainfall event. The Bangcho River, which is one of the 7 tributaries in the Cheongmi River watershed, was the study site. The Cheongmi River watershed is the second largest area for livestock excreta discharge in Korea. Our results clearly showed that, during the rainfall event, the water quality of the Bangcho River was severely deteriorated due to the COD, $NH_4-N$, T-N, $PO_4-P$, T-P, and heavy metals (Cu, Zn, and Mn) in the run-off from nearby farmlands, where the soil comprised composted manure and unmanaged livestock excreta. In addition, stable isotope analysis revealed that most of nitrogen ($NH_4-N$ and $NO_3-N$) in the run-off was from the ammonium and nitrate in the livestock excreta. The values of ${\delta}^{15}N_{NH4}$ and ${\delta}^{15}N_{NO3}$ for the Bangcho River water sample, which was obtained from the downstream of mixing zone for run-off water, were lower than those for the run-off water. This indicates that there were other nitrogen sources upstream river in the river. It was assumed from ${\delta}^{15}N_{NH4}$ and ${\delta}^{15}N_{NO3}$ stable isotope analyses that these other nitrogen sources were naturally occurring soil nitrogen, nitrogen from chemical fertilizers, sewage, and livestock excreta. Therefore, the use of physicochemical characteristics and nitrogen stable isotopes in the water quality impact assessment enabled more effective analysis of nitrogen pollution from an ILFA during rainfall events.

• Research in Plant Disease
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• 제17권2호
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• pp.142-147
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• 2011

In order to develop a environmentally friendly control protocol for managing tomato leaf mold disease in the field, we employed bacteria- and fungi-based commercially available microbial preparations. The field experiment was conducted from April to July in 2010. Average incidence rates tomato leaf mold caused by Fulvia fulva were 13.1% at the two plastic houses located in Jangsung, Jeonnam area. Initially 11 microbial preparations were tested for antifungal activity against F. fulva in vitro. Among them, 7 selected preparations showed to be inhibited the mycelial growth of the fungal pathogen over 50%. Four microbes suppressed disease incidence as much 50% under greenhouse condition. Eventually in the field two microbial products including Bacillus subtilis GB-0365 and B. subtilis KB-401 respectively were showed control value up to 71.8% for four times sprays from 20 days to 70 days after transplanting. Furthermore, the control value of three times spray program demonstrated 79.3%. Efficacy of the three and four spray programs was more effective than that of non-spray control treatment. Our results indicated that adjustment of application method of commercially available microbial preparation could be used to control a target plant disease as an effective and efficient crop protection system for organic farming.

• Korean Journal of Food Science and Technology
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• 제42권4호
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• pp.407-413
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• 2010

This study was performed to compare the quality and volatile components of two cucumber (Cucumis sativus L.) cultivars (Cheongnakhab, Ipchunakhab)-grown under organic and conventional conditions. The levels of pH and soluble solids in the organic system were similar to those in the conventional system. The hardness of the pulp in the organic cucumbers was slightly higher than that in conventional cucumber regardless of cultivar. However, the contents of chlorophyll a, b, and total chlorophyll in organic cucumbers were significantly (p<0.05) higher than those in conventional cucumber. The major volatile compound of fresh cucumber was (E,Z)-2,6-nonadienal regardless of cultivar and farming system. When classified by the identified components' functional group, the rate of aldehydes was the highest of all samples. The results indicate that the quality and volatile components in organic cucumbers were similar to those in conventional cucumbers except for hardness and chlorophyll contents regardless of cultivar.

• Journal of Venture Innovation
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• 제2권1호
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• pp.119-130
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• 2019

In this study, we intend to test whether experience variables such as sense, feel, think, relate, and action experiential activities of farming village can be usefully applied to revisit intention. As a result, we found that the sense, relate, and action experiences were adopted, while the feel and think variables were rejected, leading to the conclusion that Schmitt's (1999) experiential marketing theory was also applied to 6th industry experience marketing activities in rural areas. Therefore, the significant effect of rural experience activities on revisiting intention is thought to be related to the fact that they stimulated sensitivities by drawing attention and interest of consumers during the 6th industrial experience configuration, and to the environmental facilities connected to the experience site. The Feel experience has been rejected due to limitation of development of emotional element from the 6th industry certification business experience program, leading to the necessicity for development of a program that can stimulate the consumer's emotions. The reason why the Think experience was rejected is that the experience of the rural area 6th industry did not create surprises or curiosity, and thus does not meet the expectations of consumers. In case of relational experience, experiential marketing through social organizational relationship formation is expanding, and in case of behavioral experience, experience of 6th industry constitutes experience related to interaction with others and lifestyle.

• Journal of Animal Science and Technology
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• 제45권4호
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• pp.649-658
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• 2003

Early introducing the ducks into the paddy field involves a variety of environmental changes such as new surroundings and contact with water, so that some free-ranged ducks show behavioral and physiological changes indicative of stress or die from not adapted for new circumstances. Moreover, the free-ranged ducks was tread on the rice plant, and required a great deal of labor and time for captured the ducks after finishing the introducing. The aim of the present study was to examine the effect of accustoming and imprinting of duckling on behavior patterns, body weight gain and yield of the rice plant in paddy fields. Three paddy plots were used as control (no imprinting and no contact with people), taming (imprinting and regular handling) and roughness (handling roughly and strike terror to ducks) plots. Right after introducing the ducks into the paddy field, eating and moving behaviour of taming plot ducks tended to be longer time spend than that of other treatments. However, eating and moving time tended to be longer in the control than that of other two treatments on the 2 weeks after. Flighting distance was not showed in the free-ranging period taming plot, but the control plot was significantly (P<0.05) longer than the roughness plot. The captured time of free-ranged ducks tended to be shorter in the order of taming, control and roughness plots. Body weight gains was not significant. The number of rice plants damaged by free-ranging ducks in the taming plot were significantly (P<0.05) less than that in the control plot, but the yield and yield components of the rice plant were not differ among 3 treatments. These results indicated that the imprinting or regular handling and related treatments of duckling was reducing badly damage of rice plants, captured time and labor of free-ranged ducks in paddy field, although the working behavior of ducks and yield ability of the rice plants were not affected.

• Journal of the Korean Society of Food Science and Nutrition
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• 제36권8호
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• pp.965-974
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• 2007

This study was performed to investigate the effects of vegetable sprout powder on serum and adipose tissue lipid metabolism in rats fed high-fat diet for 4 weeks for induction hyperlipidemic model rat. Weight-matched male Sprague-Dawley rats were assigned to five groups according to dietary fat level (10% or 20% of diet wt.) and mixture of vegetable sprout powder levels (5% or 10% 10% or 20% of diet wt.). Vegetable sprout powder was the mixture of same amounts of dried barley, broccoli, rapeseed, alfalfa, radish, mustard, buckwheat and brussels sprouts. Experimental groups were normal fat diet with 5% cellulose (NF-C), high fat diet without fiber (HF-N), high fat diet with 5% cellulose (HF-C), HF-C diet with 5% vegetable sprout powder (HF-CSL), and HF-C diet with 10% vegetable sprout powder (HF-CSH). The body weight of HF-N group increased 16% compared with the NF-C group, while it was decreased by 15% and 22% for HF-CSL group and HF-CSH group, respectively. Fat mass and fat cell size of adipose tissue were lower in HF-CSL group and HF-CSH group compared with HF-C group, and lower in HF-CSH group compared with HF-CSL group. Serum triglyceride, total cholesterol and LDL-cholesterol contents were markedly decreased by vegetable sprout powder containing diet, while the serum HDL-cholesterol and phospholipid contents were higher in vegetable sprout powder containing diet in a dose-dependent manner. Leptin and insulin levels in serum showed a decrease in HF-CSH group. Significantly increased contents of triglyceride, total cholesterol, LDL-cholesterol, leptin and insulin in the serum of HF-N group were returned to normal or even below normal levels by feeding 10% vegetable sprout powder diet. The increased activities of NADP-malate dehydrogenase (ME), glucose-6-phosphate dehydrogenase (G6PDH) and 6-phosphogluconate dehydrogenase (6PGDH) and lipoprotein lipase (LPL) in adiposetissue by HF-N group were decreased to the activity of normal fat group by feeding vegetable sprout powder in a dose-dependant manner. These results indicate that lipid metabolism in rats fed high-fat diet was suppressed by feeding vegetable sprout powder.

• Journal of Fisheries and Marine Sciences Education
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• 제27권4호
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• pp.1084-1091
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• 2015

Aquaculture of olive flounder started in the middle of 1980's and now farming has been taken place in many places along the coastal line in Korea. The taste of olive flounder has a good chewy texture because of high collagen content, low fat content, so it is popular for sliced raw fish. Olive flounder is popular among Koreans but the consumption pattern is uniformly so as to be used as sliced raw fish but not other ways. So, now there needs to develop high valued-processed food using olive flounder. This study was set to investigate the processing of terrine by using olive flounder, in which terrine is French style meat loaf that is well favored around the world. In this study, terrine was prepared by chopping olive flounder meat with 39 g egg white and 10 mL fresh cream (per 50 g fillet) and then seasoned with 5 mL lemon juice, 5 mL brandy, 0.05 g salt and 0.05 g pepper. The 25 g of dough was placed on a vinyl wrap, put with 2 g cheese, and layered an another 25 g dough, and then rolled up and wrapped by aluminium foil. Two different cooking methods were used for terrine processing in this study. Terrine-1 was cooked by vacuum sealed in polyethylene film ($20{\times}30{\times}0.05mm$) after boiling for 5 min and stored at $-20^{\circ}C$ for 7 days. Terrine-2 was prepared by vacuum sealed in polyethylene film ($20{\times}30{\times}0.05mm$) and stored at $-20^{\circ}C$ for 7 days. After 7 days, Terrine-1 was thawed and then heated up in microwave for 2 min (Sample-1), while Terrine-2 was thawed and then boiled in water for 5 min (Sample-2). Viable bacterial count, chemical composition, pH, salinity, hardness, TBA, free amino acid content, and sensory evaluation were measured for both Sample-1 and Sample-2. Especially, the scores of sensory evaluation of Sample-2 is slightly higher than that of Sample-1. On the other hand, there were no significant differences on color, odor, taste, texture, and overall acceptance between Sample-1 and Sample-2.