• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.12
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• pp.1129-1135
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• 2013

In this, three types of natural gas were employed to investigate the effect of low-calorific natural gas on the performance of and emissions from a heavy-duty CNG engine. The performance and emission characteristics were analyzed by conducting a full-load test, WHSC mode test, and WHTC mode test. The results showed that the torque of low-calorific natural gas with $9,800kcal/Nm^3$ of higher heating value decreased by 4.4 compared to that of the current natural gas with $10,400kcal/Nm^3$ of heating value. With low-calorific fuels, CO, $CO_2$, and $NO_x$ emissions decreased. However, THC emissions increased. According to the WHSC and WHTC mode test results, the thermal efficiency increased and the emission characteristics showed a similar trend to the full-load test results. Low-calorific natural gases cause a decrease in torque at full-load operation conditions and an increase in hydrocarbon emissions.

• Journal of the Korean Society of Food Culture
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• v.18 no.3
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• pp.261-269
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• 2003

This was preliminary study that was to find out the developing point in military meal service to focus on seafood dishes that recently increased plate waste. This study was conducted to analyze menu patterns in military meal service. The result of this study was using to develop new seafood dishes in military meal service. On the basis of some findings, several developing points how to plan meals include many kinds of seafood dishes and to modify taste and cooking method that was more highly prefered by young military persons were suggested. This preliminary study findings were as follows: 1. Each meal was served cooked rice and 4 kinds of dishes(soup or stew, main dish, side dish and kimchi) 2. The seafood dishes was served as 28.6% in soup or stew, 35.0% in main dish and 36.4% in side dish of total serving of seafood dishes. 3. All of raw materials of seafood were supplied by frozen, several items were supplied dried material. Supplying seafood items were limited. Numbers of using seafood items were using 2.7 times per day. Laver and squid was most frequently used. 4. Seafood dishes were frequently serving in breakfast, especially seasoned & toasted laver was served 28.8% of seafood menu in breakfast because of convenience. 5. The nutrients contents of each dishes were as follows, the soup was $86.5{\pm}3.2kcal$ and $10.9{\pm}8.9g$ of animal protein, stew was $165.3{\pm}70.2kcal$ and $13.3{\pm}7.9g$ of animal protein. Nutrients content of other main dish and side dishes was different from 108.1kcal (in steaming dish) to 412.4kcal (in deep-fat frying dish) according to different cooking method. The highest animal protein dish that contented $18.9{\pm}5.1g$ of protein was pan-frying dish or grilling dish. Lowest one was $8.4{\pm}4.9g$ in braising dish. 6. Major cooking method of seafood was stew and the next was deep fat frying, stirfrying and braising. Pan-frying or grilling was seldomly used in military menu because of limitation of kitchen facilities and cooking utensils. On the basis of these findings, newely developing military seafood menus were focused on combination dish(such as seafood cooked rice or seafood fried rice) and many kinds of sauce that was applied to deep-fat frying dishes.

• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.256-260
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• 1992

This study was conducted to calculate and predict the shelf-life of meat sausage through physicochemical and biological analysis. Judging from physico-chemical components, it can be found out the most effective indicator in meat sausage. And also, the materials used for packaging is cellulose #23 in inner-packaging and CN/HDPE laminating film in outer-packaging. The changes of the most effective indicator were discussed through the method of kinetic analysis. Judging from physico-chemical components, VBN was the most available component in quality judgement of meat sausage and their upper limiting contents were 20 mg%. It is possible to calculate and predict the shelf-life of meat sausage through the regression equation and $Q_{10}$ value. As a result, the shelf-life prediction was $58{\sim}63$ days at $10^{\circ}C$, $47{\sim}51$ days at $20^{\circ}C$ and 26 days at $40^{\circ}C$, respectively, but the difference between two methods showed about $4{\sim}5$ days. $Q_{10}$ value on the changes contents was 1.35 at acceralated temperature $40^{\circ}C$. The reaction rate of VBN contents could be interpreted as a first order reaction that divided into 2 periods with different reaction rate constants. The corresponding Arrhenius activation energies were 2.959 Kcal/mole and 3.632 Kcal/mole, respectively.

• Korean Journal of Materials Research
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• v.4 no.6
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• pp.638-643
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• 1994

The Si(ll1) surface structures induced by deposition of Au atoms were investigated by RHEED system. When Au atoms were deposited on the Si(ll1) $7\times7$ surfade, the dependence of structures and phases on the substrate temperatures and coverages was drastic. For O.1ML to 0.4ML of coverage the $7\times7$ structure changes to $7\times7$ + $5\times2$ structure as temperature increases to $350^{\circ}C$-$750^{\circ}C$. Between 0.4M1 to 1.OML the phase changed to $5 \times 2,\alpha- \sqrt{3} \times \sqrt{3},\beta- \sqrt{3} \times \sqrt{3}$ structure according to the substrate temperature and coverages. When the coverages exceeds O.SML, the 6 x 6 structure appears at the substrate temperature range between $270^{\circ}C$-$370^{\circ}C$ and compeletely transforms to 6 x6 at 1,OML. The isothermal desorption of Au on Si(ll1) surface investigated by using AES in the $\alpha- \sqrt{3} \times \sqrt{3},5 \times 2$ structures shows that the desorption energys of $\alpha- \sqrt{3} \times \sqrt{3}$ and 5 x 2 were 79Kcal/mol and 82 Kcal/mol respectively.

• Resources Recycling
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• v.7 no.5
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• pp.33-40
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• 1998

The formation reation of anhydrite (CaSO$_{4}$) depends upon the amount and velocity of the SO$_{3}$(g) and CaO(s) produced in the process of the thermal decomposition of alunite[K$_{2}SO_{4}{\cdot}Al_{2}(SO_{4})_{3}{\cdot}4Al(OH)_{3}$] and limestone (CaCO$_{3}$) respectively. Therefore, this study had carried out to investigate the amount and velocity of SO$_{3}$(g) produced by roasting alunite and pyrolytic materials. In air, alunite was transfouned into KAl(SO$_{4})_{2}$ and Al$_{2}O_{3}$ by dehydration at 500~580$^{\circ}C$. The dehydration velocity of alunite was found to be kt=(1-(1-${\alpha})^{1/3})^{2}$, the activation energy, 73.01 kcal/mol. SO$_{3}$(g) ware slowly produced by the thermal decomposition of KAl(SO$_{2})_{2}$, at 580~700$^{\circ}C$, rapidly, at 700~780$^{\circ}C$, The pyrolysis velocity of KAl(SO$_{4})_{2}$ was found to be kt=1-(1-${\alpha})^{1/1}$; activation energy, 66.84kcal/mol. The SiO$_{2}$ and kaolinite in alunite ore scarcely affected the temperature and velocity in which SO$_{3}$(g) were produced.

• Journal of Nutrition and Health
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• v.11 no.4
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• pp.31-38
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• 1978

Younghung-myun is located on a small island under the jurisdiction of Gyunggi province. The island occupying a total of approximately 40sq km is populated by 5,850 people. Two areas within the island were selected for this survey; 1) Nae 4-ri in Younghung-myun (mainly engaged in farming) 2) Nae 5-ri in Younghung-myun (mainly engaged in fishery) The survey was conducted for the period of 5-12 august 1978. Intake of foods and nutrients of all members in the households surveyed by means of questionnaire was computed based on number of meals a day. On the other hand, daily intake of nutrients by an individual was calculated by sex, age and type of work based on the conversion rate of RDA (Korean Recommended Dietary Allowances for Adult). The results obtained are summarized; 1. Status of food intake Average daily food intake of an individual in the surveyed areas was 1,018gm. Out of 1,018gm above, 490gm which represent 48% of the total intake were from cereals, grains or other vegetative products. Ratio of animal-origin foods was determined as only 16% of the total intake. These findings led us to the conclusion that people in the surveyed areas live heavily on vegetative foods. 2. Status of nutrients intake 1) Overall average intake of calorie by an individual in the surveyed areas was 2026.3Kcal per day. On the other hand, average calorie intake by adult persons was 2,491.3 Kcal per day, which is lower than 2,700 Kcal recommended by RDA by approximately 7.7%. Furthermore, it was observed that most of 2,491.3 Kcal obtained by adult persons was from such vegetative foods as cereals, grains, ect. 2) Overall average intake of protein by an individual in the areas surveyed was 52.2gm per dar. On the other hand, average protein intake among adult persons was 67.7gm a day, which indicates lower intake of protein than 80gm of RDA. It was also found that 84.3% of the protein intake by an adult person was of plant origin. 3) Overall average of fat intake by an individual in the areas surveyed was 18.9gm per day, whereas average fat intake among adult persons was 23. 2gm a day. It was brought to our attention that the average fat intake by adult persons is much lower than 36gm recom mended by RDA. 4) Average calcium intake among adult persons in the areas surveyed was 457.1mg per day, that is somewhat lower than 500mg in RDA. However, average iron intake among adult persons in the areas was slightly higher with 10.5mg a day than 10mg of RDA. 5) With exception with vitamin C, intake of all other vitamin groups, such as vit. A, vit. $B_1$, vit. $B_2$ and niacin, were lower among the inhabitants than recommended by RDA. 3. Economic status Average schooling years of food handlers was 6.5 years with average monthly income of \89,000 in the areas surveyed. Petroleum was used by majority of the households for fuel.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.6167-6175
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• 2012

This study is experimental analysis to verify heating efficiency of Ondol in floor heating panel developed. For this one, an experiment tests producing an each test speciment and measuring heating efficiency. The result of an experiment, supplying hot water temperature is $45^{\circ}C$ and the result of measuring on parts temperature of test speciment on supplying for 8 hours, mortar surface that is superstructure plumbing of heating system developed is $49.4^{\circ}C$, the gap of piping on center of mortar surface is $44.1^{\circ}C$ and airspace is proved $25.3^{\circ}C$. In floor structure of standards, mortar surface is $46.2^{\circ}C$, the gap of piping on center of mortar surface $37.7^{\circ}C$ and airspace is $24.7^{\circ}C$. On the other hand, energy consumption accumulating of development technology is identified, in case of hot-water supply on $45^{\circ}C$ as 4,646 kcal and in existing technology, as 4,814 kcal. developing technology is verified and lower than existing technology.

• Journal of Nutrition and Health
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• v.42 no.5
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• pp.474-485
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• 2009

The purpose of the present study was to evaluate the characteristics of nutrient intakes of adults aged 20-64 years in Daegu and Gyeongbuk areas in comparison with Seoul and the whole nation. Data from the 1st (1998) to 3rd (2005) Korean National Health and Nutrition Examination Survey (KNHANES) were used. Total numbers of subjects were 296-369 from Daegu and 307-447 from Gyeongbuk while 1076-1244 from Seoul and 5436-6852 from the whole nation. Average energy intakes (men; 2,386, 2,581, 2,305 Kcal, women; 1,937, 1,981, 1,804 Kcal in 1998, 2001, 2005, respectively) of the subjects from Daegu were higher than those from Gyeongbuk (men; 2309, 2267, 2487 Kcal, women; 1,851, 1,845, 1,901 Kcal) and those from Seoul in 1998 and 2001 but not different from those in 2005. Energy from carbohydrate was consistently higher in the subjects from Daegu and Gyeongbuk than in those from Seoul from 1998 to 2005, when the subjects whose carbohydrate energy was over 70% comprised 34 to 58% of the total in the two regions. In 2005, the average intakes of calcium of women and men from Daegu were 512 and 573 mg, iron, 12.8 and 16.6 mg, sodium, 4,650 and 5,951 mg, potassium, 2,585 and 3,152 mg, vitamin A, 823 and 1,038 ${\mu}$gRE, thiamin, 1.10 and 1.43 mg, riboflavin, 1.08 and 1.33 mg, and niacin. 15.4 and 19.3 mg, and vitamin C, 94 and 105 mg and these intakes were not very different from those from Gyeongbuk except higher sodium intake of the Gyeongbuk subjects. Nutrients of which the intakes were over 50% lower than EAR were calcium and riboflavin and those about 30% lower than EAR were iron in women, vitamins A and C in men and women from Daegu and Gyeongbuk. From the present results, it is concluded that high dependence on carbohydrate as energy source and low calcium intake in adults of Daegu and Gyeongbuk are serious and that low intakes of riboflavin, iron and vitamins A and C need to be improved. But changes in the intakes of total energy and other micronutrients from 1998 to 2005 were not reliable enough to judge the regional nutrition due to large variations during this period. The present study also provides the adults' nutrient intakes separated by sex and age groups in the three regions which could be readily used for setting up the nutrition policy for the adults in the regions.

• Nutrition Research and Practice
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• v.12 no.4
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• pp.336-341
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• 2018

BACKGROUND/OBJECTIVES: Dietary Reference Intakes (DRI) for energy are derived from total energy expenditure (TEE) measured using the doubly labelled water (DLW) method. The objective of this study was to assess the validity of DRI for predicting the energy requirements of elementary school-age children. SUBJECTS/METHODS: The present study involved 25 elementary school-age children aged between 9 and 11 years. TEE was assessed by the DLW method, and the results were compared with the TEE predicted by the DRI equations in order to evaluate accuracy. RESULTS: The subjects' TEE measured by the DLW method was $1,925.2{\pm}380.9kcal/day$ in boys and $1,930.0{\pm}279.4kcal/day$ in girls, whereas resting energy expenditure was $1,220.2{\pm}176.9kcal/day$ in boys and $1,245.9{\pm}171.3kcal/day$ for girls. The physical activity level was $1.58{\pm}0.20$ in boys and $1.55{\pm}0.13$ in girls. The mean bias between the predicted and measured TEE was 12.6% in boys and -1.6% in girls, and the percentage of accurate predictions was 28.6% and 63.6%, respectively. In boys, the equation resulted in underprediction of TEE among the subjects having low TEE values, whereas there was overprediction among subjects having high TEE values as shown by the Bland-Altman plot. On the contrary, this proportional bias was not observed in girls. CONCLUSIONS: The findings of this study suggest that the DRI equation for energy could result in the overestimation of energy requirements in elementary school-age boys. In the case of girls, the equations could be accurate at the group level. However, the DRI appears to be invalid for individual girls, as more than one third of girls had their TEE inaccurately predicted. We recommend more studies for confirmation of these results.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.10
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• pp.731-738
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• 2011

In this study AOPs of $O_3/UV$ radiation, $O_3/Mg(OH)_2/UV$ radiation and $O_3/MgO/UV$ radiation system for phenol treatment in aqueous solution was performed in a laboratory scale circulating batch reacter. Flow rate of ozone 1.0 L/min, ozone concentrations $150{\pm}10mg/L$ was maintained constantly at the above-mentioned oxidation processes. During the oxidation processes the $COD_{Cr}$ and TOC was measured in the composition. The pseudo first-order rate constants of the processes was $5.12{\times}10^{-5}$, $1.19{\times}10^{-4}$ and $1.79{\times}10^{-4}sec^{-1}$, and the activation energy was 3.03, 1.79 and $2.32kcal{\cdot}mol^{-1}$ at $20^{\circ}C$, respectively. It was found that both $Mg(OH)_2$ and MgO had remarkable accelerations on degradation of phenol and removal of COD in water. On this basis, $O_3/MgO/UV$ system is an effective and feasible routes for catalytic ozonation of phenol in water.