• Analytical Science and Technology
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• v.15 no.2
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• pp.142-148
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• 2002

They were analyzed that the levels of PCDDs/PCDFs in mackerel, walleye pollack, croaken and cuttlefish, which were mainly consumed in Korea, by high resolution gas chromatography/high resolution mass spectrometr (HRGC/HRMS). The samples measured in this study had been bought 3 sets of each fish from different 5 cities, Seoul, Chunchon, Daejon, Kwangju and Pusan. The TEQ level of PCDDs in mackerel (0.032 pgTEQ/g) was the highest. The TEQ level of PCDFs in walleye pollack (0.010 pgTEQ/g) was the lowest. The level of PCDDs was higher than PCDFs in fish.

• Journal of the Korean Dietetic Association
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• v.2 no.1
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• pp.69-80
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• 1996

This study was performed to investigate the food preference trends of the children according to age increase and change of the times. The subjects were 1,450 children who are fifth grade of primary school and 2,000 juveniles who are senior high school in 1993. This survey data were compared with the Food preference study of the primary school aged children in 1987.' The results of this study can be summarized as follows 1. State of the general taste The subject had a high preferences to bulgogi(roast beef), panbroiled cuttlefish, steamed egg, fried sausage and donuts among the all sorts of 165 principal and subsidiary foods. But, fried beef liver, pancake, sweet potato with syrup, spinach soup and boiled rice with red bean didn't suit for their taste. Compared with survey data done in 1987, in present study significantly increased preferences to steamed food, pan frying and parboiled vegetables were shown. Particularly, food preference was changed with the cooking methods rather than materials. 2. Differences of the preference according to change of the times In present study, except the rice cakes preferences to all sorts of foods were improved and markedly increased preferences to steamed food, parboiled vegetables and mixed with seasonings were observed. Compared with 87's study deviation of the preference to cooking materials was decreased considerably. Preferences to salty tasted foods as like as stew and salted food were low no better than before. 3. Changes of preference according to age increase Among the principal foods, increased preferences to boiled rice and cereals were shown but to one-dish meal, bread and rice cake were decreased. Among the subsidiary foods, significantly decreased preference to frying was observed. Irrespectively of the cooking methods, preferences to fish and vegetables were improved. And in the frying and panbroiled foods, deviation of preferences to cooking materials were considerable, which means the fixation of food behavior.

• Journal of The Korean Association For Science Education
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• v.16 no.4
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• pp.451-460
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• 1996

The ethical issue is one of the most important themes in both science and environmental education. Especially related to the right of other species, animal dissection has been brought about two contradictory attitudes. In spring 1996, a survey was conducted to assess the status of animal dissection in secondary schools and the awareness of 94 biology teachers and 422 secondary students toward animal dissection. And the meaning of animal dissection in biology class was discussed in terms of environmental education. The findings were as follows: First, most of students(96.6%) had participated once or twice to animal dissection experiments(eg. fish, frog, shellfish, cuttlefish and chicken). And about half of teachers (57.4$\sim$64.9%) and some students(41.9%) felt ethical conflict in animal dissection. Second, many teachers(81.0%) and students(87.1%) thought that animal dissection was effective method to achieve the goal of biology education, but they needed more consideration on the respect for life in animal dissection experiment. Third, many teachers(88.3%) had students, who objected to animal dissection, participate obligatorily or passively. Fourth, teachers and students thought that audio-visual media such as video(teachers 63.5%, students 39.7%), computer simulations(teachers 31.7%, students 28.1%) and models(teachers 22.2%, students 24.1%) could be effective as alternatives. These findings suggest that animal dissection experiment, although it is needed to achieve the goal of biology education, requires careful consideration on the rights of animal and the respect for life, and alternatives for students who object to animal dissection in biology class.

• Journal of the Korean Society of Food Culture
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• v.12 no.3
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• pp.289-299
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• 1997

This study was performed with survay in the field and literature. The result were; 1. In Vietnam, They took their meal in three times a day. They have taken Nuoc nam (fish sauce) with sliced red pepper, half a lime, etc... in every day every night. Fish Sauce was prepared with small fish (generally fresh- water fish), the same amount of salt, and stored in 8 months, and made filltered fluid. It's Nuoc mam. They have gained protein sauce from it. 2. Their basic menu were composed with rice, soup, food with marine products and meat (generally pork), various vegetables, tropical fruit. 3. Food of cereals were Com Trang (white rice), Pho (rice noodle), Chao (rice gruel), Banh Trang (rice paper), Banh mi (bread) etc... Food of meat were Ho sua, Banh bao chien (barbecued little pork), Suon Nuon (grilled pork), Cha Lua (sausage of pork) etc..., Thit be nhung (grilled beef, Dog meat, Chicken, Duck, Frog. Food of fish were generally fresh-water fish, Ca Chien (grilled fish), Canh chua (soup with sour taste), Ca chem chung (steamed fish with fragrant vegetable), Lobster, Crab, Oyster, Cuttlefish, Shellfish, etc... Food of vegetables were Doa Hanh (Kimchi with a welsh onion), Rau xao hon hop (roasted vegetables), Goi Tom (salad), Canh he dau hu (soup) etc..., and They took much food of trophical fruit, Tra (Tea), Coffee, Lua Moi (distilled liquor). 4. For example, Their Daily meal were composed of Sup Bong Ca (Soup), Heo Sua, Banh Bao Chien (barbecued little Pork), Top Hap (steamed shrimp), Cua (steamed Crab), Luon Um (bioled a fresh-water eel), Lau Thap Cam, Hai Sam Sac Nam Dong Co, Trai Cay.

• Steel and Composite Structures
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• v.45 no.2
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• pp.205-218
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• 2022

Proper calculation of splitting tensile strength (STS) of concrete has been a crucial task, due to the wide use of concrete in the construction sector. Following many recent studies that have proposed various predictive models for this aim, this study suggests and tests the functionality of three hybrid models in predicting the STS from the characteristics of the mixture components including cement compressive strength, cement tensile strength, curing age, the maximum size of the crushed stone, stone powder content, sand fine modulus, water to binder ratio, and the ratio of sand. A multi-layer perceptron (MLP) neural network incorporates invasive weed optimization (IWO), cuttlefish optimization algorithm (CFOA), and electrostatic discharge algorithm (ESDA) which are among the newest optimization techniques. A dataset from the earlier literature is used for exploring and extrapolating the STS behavior. The results acquired from several accuracy criteria demonstrated a nice learning capability for all three hybrid models viz. IWO-MLP, CFOA-MLP, and ESDA-MLP. Also in the prediction phase, the prediction products were in a promising agreement (above 88%) with experimental results. However, a comparative look revealed the ESDA-MLP as the most accurate predictor. Considering mean absolute percentage error (MAPE) index, the error of ESDA-MLP was 9.05%, while the corresponding value for IWO-MLP and CFOA-MLP was 9.17 and 13.97%, respectively. Since the combination of MLP and ESDA can be an effective tool for optimizing the concrete mixture toward a desirable STS, the last part of this study is dedicated to extracting a predictive formula from this model.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.15 no.2
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• pp.67-76
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• 1979

Diurnal variation of the catch of some important species groups in the Northwestern coast of Africa were studied on the basis of fish catching data compiled by a stern trawler(G.T., 499ton 2,200ps). The experimental fishing has been conducted from September, 1975 to August, 1976. The catch of the important groups I. e. squid, cuttlefish, octopus, sole fish and sea bream revealed different fluctuation patterns. The results obtained are as follows: 1. The catch of squid caught in daytime(0900-1800) was greater than that caught in night (2100-0600). 2. The catch of cuttle fish caught in daytime was more than that caught in night. In the daytime, large size group(heavier than 300g) was caught dominately during midday (1200-1500) whereas the small size group, lighter than 300g, was caught dominately during the time of sunrise (0600-0900) and sunset (1800-2100). 3. The catch of octopus varied according to the size groups. The large sige group, heavier than 700g, was caught predominately during daytime and the small size group, lighter than 700g, was caught predominately during night. 4. The catch of sole fish caught in night was greater than that caught in daytime. 5. The catch of sea bream and miscellaneous fishes including sardin, jack-mackerel and etc. was greater in daytime.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.3 no.3
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• pp.161-171
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• 1970

1. The higher the temperature of the sea water, and the smaller the size of the oriental brown shrimp, the higher the feeding rate of the shrimp will be as long as the temperature ranges from $19^{\circ}\;to\;30^{\circ}C$, and each shrimp weighs from 1.6 to 14.9 grams. The average daily feeding rate is between 18 to 44 percent. 2. The nighttime feeding rate is always higher than the daytime feeding rate. However, the daytime feeding rate can be raised to from 22 to 37 percent of the daily feeding rate iii the non-sediment, dark or direct-sunshine-shielded conditions. Growth can thus be accelerated to that extent under such conditions. 3. When anchovy and short-necked clam meats were simultaneously used as food, a greater quantity of anchovy meat was consumed than short-necked clam meat both during the daytime and nighttime. When anchovy and short-necked clam meats were simultaneously given, the averaged daily feeding rates of anchovy and short-necked clam meats were 12.9 percent and 10.3 percent, respectively. 4. The following equation applies to the relationship between the freight of the oriental brown shrimp (W in grams) and their daily growth rate (DGR in percent): log DGR=0.7035-0.7864 log W. The daily growth rate is in inverse proportion to the size of the shrimp. 5. The efficiency of food conversion of the oriental brown shrimp fluctuates between 2.8 and 7.8 percent without extensive difference depending on the size of the shrimp. This was very small as compared with the corresponding figures so far known for fish and cuttlefish.

• Development and Reproduction
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• v.20 no.2
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• pp.119-125
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• 2016

This study describes results on sexual maturation and characteristics of natural spawned eggs to develop a method for the production of stable, healthy fertilized eggs from captive-reared yellowtail kingfish, Seriola lalandi. A total of 59 yellowtail kingfish were captured off the coast of Jeju Island, after which the broodstock was cultured in indoor culture tank ($100m^3$) until they were 6.1-14.9 kg in body weight. As part of the rearing management for induced sex maturation, the intensity of illumination was maintained at 130 lux. The photoperiod (light/dark; L/D) was set to a 12 L/12 D from October 2013 to January 2014, and 15 L/9 D from February 2014 to June 2014. Feeds comprised mainly EP (Extruded Pellets), with squid cuttlefish added for improvement of egg quality, and was given from April to June 2014. The first spawning of yellowtail kingfish occurred in May 3, 2014, at a water temperature of $17.0^{\circ}C$. Spawning continued until June 12, 2014, with the water temperature set at $20.5^{\circ}C$. Time of spawning was 26 times at this period. The total number of eggs that spawned during the spawning period was $4,449{\times}10^3$. The buoyant rate of spawning eggs and fertilization rate of buoyant eggs during the spawned period were 76.1% and 100%, respectively. The diameters of the egg and oil globule were $1.388{\pm}0.041mm$ and $0.378{\pm}0.029mm$, respectively, which was higher in early eggs than in those from late during the spawned period.

• The Journal of Korean Society for School & Community Health Education
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• v.12 no.1
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• pp.59-70
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• 2011

Methods: This study was performed to estimate the use of frozen convenience food in middle schools located in the Daegu district. Objectives: These schools have directly managed school meal services. The subjects for this study were 145 students and 66 dieticians. The study involved a survey on food preference and quantity satisfaction of the students and the frequency of use of frozen convenience food in the daily menu. Results: As the result, 50.0% of the students were not satisfied with the meat and poultry quantity from school meals(felt small), and 25.0% of students were not satisfied with vegetables(felt much). The majority of students (50.7%) who were not satisfied with vegetables said they were dissatisfied with the school food because of the taste. On the other hand, 36.6% said they were dissatisfied because they dislike vegetables in general. As for the use and frequency rate of frozen convenience food, the survey results were revealed in the order of dumpling 58.3% > processed meat 50.0% > chicken 50.0% > frozen marine food 40.4% > cuttlefish 30.3% > miscellaneous 26.3% > vegetable & potatoes 14.4%. It was found that many schools employing more than five workers did not use flour-based frozen foods in their menu. As for the use of the frozen processed food, many schools which had an average food cost of more than 1,700 Won were found to use frozen foods more than once a month. In addition, chicken was not used often at the schools whose average food cost was less than 1,500 Won while many schools, whose average food items cost was more than 1,500 Won, incorporated chicken into the menu once a month. Processed flour food [hot dog] was used often by schools whose average food cost was between 1,500 Won and 1,600 Won. As for the actual conditions of using frozen convenience food, there was a significant difference in the use of chicken in relation with the number of food service recipients. As a result, the use of frozen convenience food has been shown to be related with food cost, number of food preparers, and the number of school students.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.577-583
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• 2011

In 2007, pet food contaminated with melamine caused hundreds of dogs and cats to develop renal failure all over the world. In 2008, over 294,000 infants consumed infant formula and developed kidney stones in China. Further investigation revealed that fish feed also contained melamine; this raised concerns about melamine residues in edible fish tissues, which could have caused the urinary tract stone epidemic. In Korea, catfish fed with assorted feed that included cuttlefish organs that contained melamine developed whitening syndrome and fell dead in some populations in 2008. This event raised suspicions about the toxicity of melamine and all feeds containing melamine were immediately recalled. In this study, we investigated the rates of melamine accumulation and depletion in muscle and viscera of catfish to propose proper withdrawal periods. One group of catfish was fed a commercially available diet that contained 30, 100 and 300 mg melamine per kg diet for 14 days. To investigate residual melamine contents in muscle and viscera, other experimental groups were fed a melamine free diet after being fed melamine for 7 days. The residual amount of melamine was analyzed by LC-MS/MS. The melamine concentration in muscle was estimated to be 3.7 mg/kg after 6 days of feeding with a diet containing 300 mg melamine/kg. After 2 days of culture with a melamine free diet, the residual melamine was depleted and the concentration had decreased from 1.15 mg/kg to 0.19 mg/kg in the muscle of catfish fed a diet containing 300 mg melamine/kg for 7 days. The residual amount of melamine was reduced to 0.03 mg/kg in muscle after 7 days of culture with a melamine free diet and was undetectable after a prolonged culture period of 14 days. Catfish tend to excrete melamine rapidly after oral administration and changes in body color were not observed during the short dosing period.