• Korean Chemical Engineering Research
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• v.59 no.3
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• pp.345-358
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• 2021

This study focuses on the development of the liquid air production process that uses LNG (liquefied natural gas) cold energy which usually wasted during the regasification stage. The liquid air can be transported to the LNG exporter, and it can be utilized as the cold source to replace certain amount of refrigerant for the natural gas liquefaction. Therefore, the condition of the liquid air has to satisfy the available pressure of LNG storage tank. To satisfy pressure constraint of the membrane type LNG tank, proposed process is designed to produce liquid air at 1.3bar. In proposed process, the air is precooled by heat exchange with LNG and subcooled by nitrogen refrigeration cycle. When the amount of transported liquid air is as large as the capacity of the LNG carrier, it could be economical in terms of the transportation cost. In addition, larger liquid air can give more cold energy that can be used in natural gas liquefaction plant. To analyze the effect of the liquid air production amount, under the same LNG supply condition, the proposed process is simulated under 3 different air flow rate: 0.50 kg/s, 0.75 kg/s, 1.00 kg/s, correspond to Case1, Case2, and Case3, respectively. Each case was analyzed thermodynamically and economically. It shows a tendency that the more liquid air production, the more energy demanded per same mass of product as Case3 is 0.18kWh higher than Base case. In consequence the production cost per 1 kg liquid air in Case3 was $0.0172 higher. However, as liquid air production increases, the transportation cost per 1 kg liquid air has reduced by $0.0395. In terms of overall cost, Case 3 confirmed that liquid air can be produced and transported with $0.0223 less per kilogram than Base case.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.1
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• pp.26-31
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• 2022

This study was carried out to evaluate the growth characteristics and forage yield potential for warm season grass as emergency forages. The experimental design was a randomized block design (RBD) with three replications. Two barnyard millet (Echinochloa species cv. Shirohie and Jeju native), a pearl millet (Pennisetum glaucum cv Feed milk 2) a proso millet (Panicum miliaceum cv Native), a teffgrass (Eragrostis tef cv. Tiffany) and a kleingrass (Panicum coloratum cv. Selection 75) were compared for forage production and quality at the Mid regions of Korea. Warm season forage crops were sown on May 21 and June 23 respectively, and in 2021, it was sown twice on May 21 and June 21 The number of days to seedling emergence for barnyard millet and teffgrass was observed approximately 10 and 3 days after seeding, respectively. The cultivation period from seeding to harvest was within 60 days for all entry spices except for the late-heading type barnyard millet (within 84 days). As for the dry matter yield by seeding date, the dry matter yield of the late-heading type barnyard millet in May seeding was the highest at 23,872 kg/ha, and the kleingrass was the lowest at 3,888 kg/ha. For the June seeding, the dry matter yield of the late-heading type barnyard millet was 17,032 kg/ha, the highest, and the proso millet, teffgrass and kleingrass showed the lowest at 5,468, 5,442, and 5,197 kg/ha, respectively. The crude protein (CP) content was varied by warm season grass species, but the early-heading type barnyard millet, teffgrass, and kleingrass showed the highest tendency, and the late-heading type barnyard millet showed the lowest at 5.7~5.9%. Neutral detergent fiber (NDF) and acid detergent fiber (ADF) content did not show a significant difference between the seeding in May, but kleingrass in June sowed lower than the others.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.6
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• pp.152-161
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• 2023

In general, large-capacity hydrogen storage vessels, typically in the form of vertical cylindrical vessels, are constructed using steel materials. These vessels are anchored to foundation slabs that are specially designed to suit the environmental conditions. This anchoring method involves pre-installed anchors on top of the concrete foundation slab. However, it's important to note that such a design can result in concentrated stresses at the anchoring points when external forces, such as seismic events, are at play. This may lead to potential structural damage due to anchor and concrete damage. For this reason, in this study, it selected an vertical hydrogen storage vessel based on site observations and created a 3D finite element model. Artificial seismic motions made following the procedures specified in ICC-ES AC 156, as well as domestic recorded earthquakes with a magnitude greater than 5.0, were applied to analyze the structural behavior and performance of the target structures. Conducting experiments on a structure built to actual scale would be ideal, but due to practical constraints, it proved challenging to execute. Therefore, it opted for an analytical approach to assess the safety of the target structure. Regarding the structural response characteristics, the acceleration induced by seismic motion was observed to amplify by approximately ten times compared to the input seismic motions. Additionally, there was a tendency for a decrease in amplification as the response acceleration was transmitted to the point where the centre of gravity is located. For the vulnerable components, specifically the sub-system (support columns and anchorages), the stress levels were found to satisfy the allowable stress criteria. However, the concrete's tensile strength exhibited only about a 5% margin of safety compared to the allowable stress. This indicates the need for mitigation strategies in addressing these concerns. Based on the research findings presented in this paper, it is anticipated that predictable load information for the design of storage vessels required for future shaking table tests will be provided.

• Journal of Animal Environmental Science
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• v.10 no.1
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• pp.47-58
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• 2004

This work was carried out to investigate the effects of rice hull continuously utilized and/or replenished on the composting properties and to obtain the fundamental data between an unsupported wall and a soil supported wall during the period of composting with pig slurry in winter season. There were no the temperature holding effects in soil supported wall. New compost facility design for the temperature holding effects from a soil supported wall was required. The results were as follows; 1. Composting 1㎥ of pig slurry caused to save on 0.31㎥ of bulking agent in the unsupported wall in comparison with a soil supported wall in the rice hull single addition, and 0.45㎥ in the rice hull gradual addition. 2. The pile in the rice hull single addition had a high temperature in 4 days of composting indicating $71^{\circ}C$ and had a tendency in repeating periodically between $40^{\circ}C$ and $65^{\circ}C$ till 43 days of composting. And also the temperature of the pile was maintained between $48^{\circ}C$ and $28^{\circ}C$ after 50 days of composting. The pile of a rice hull gradual addition had the lower point of the temperature high increasingly according to adding up rice hull during the 35 days of composting. 3. The pH recorded in the rice hull single addition was higher(8.35∼10.02) compared to the rice hull gradual addition(8.6∼9.8). The pile of a rice hull single addition had a tendency in abruptly decreasing pH of the unsupported wall during the period of between 0.363$\textrm m^3$ and 0.537$\textrm m^3$ as a unit of pig slurry per rice hull. EC depending upon the way in adding rice hull was changed between 1.10 mS/$\textrm {cm}^3$ and 1.87 mS/$\textrm {cm}^3$. 4. The organic matter in an unsupported wall of the hull single addition was maintained the level of 55% during the period between 0.119㎥ and 0.363㎥ as a unit of pig slurry per rice hull while in the soil supported wall between 48 and 70. Water soluble C:N ratio was maintained between 1 and 2 in the rice hull single addition, while between 1 and 3 in the rice hull gradual addition. 5. Fertilizer constituents were detected higher level in the unsupported wall than in the soil supported wall in all treatments. This was dependant upon the input of pig slurry.

• Journal of the Korean Society of Costume
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• v.1
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• pp.119-129
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• 1977

It is significant for developing the future for us to know our present age. In order to preserve our Korean costume as a fola clothes retaining our distinguished independent characterisitics and to help design the tomorrow of our Korean costume playing a role as a racial to develop the world clothing culture, a survey was conducted to investigate modern people's conscious-ness and wearing practumes of Korean costume by questionaire and interviewing methods. The results of the survey were analyzed as follows: (1) At present, Korean costumes were purchased as customtailored(64.0%) and as ready-made(17.8%) and most of them were not made at individual homes. The laundry and ironing of them were carried out at laundry shops(68.8%). Considering our present economic, social and cultural aspects, sowing, laundryand ironing will not be carried out at homes again in the future and ready made costumes seen to be produced in a large scale in the future. Garment makers and laundry shop operators should be trained how to make our Korean costumes retain our traditional beauty in the course of their production and laundry and the makers of ready-made costumes must make research how to efficiently produce ideal ready-made costumes by adopting the synchro system in their wrk odisivion. (2) The age group wearing Korean costumes most frequently was the aged people over 60 (their wearing rate; 45%-50%) and the group wearing them most frequently next io the aged people over 60, was housewives(their wearing rate; 15%-20%). Excludign aged people and housewives, other respondentsdid not wear Korean costumes very frequently. Men's wearing rate was lower their wearing rate was the younger their ages were and the less their monthly incomes were. Korean costumes were used for holiday and festival(60%), wedding and funeral ceremonies (52%), visiting and working(22%), casual wear(12.8%) and home wear(9.2%). The use of Korean costumes as casual and home wears, was lower than the use for holday, festival, visiting and working, Under our present circumstances in which our Korean people use both Western style clothes and Korean costumer, our Korean costume has lostits position as a basic and necessary requiement in Korean people's daily life and become a ceremonical and fancy costume. It is natural that the times and life change everything in our daily life. Our costume has to be made as good ceremonial and fancy clothes satisfying modern sensibility according to its new role. In order for us to get close with our clothes, a keen study must be carried out to cleat the color, material, style, function and harmony of the Korean costume matching the of the times. (3) The 47.8% of the respondents answered that they were proud of our Korean costume as our folk clothes, 47.6% replied that thought them just common and 1.1% responded that they were ashamed of it. Most of them were affirmative in feeling pride with our Korean costume. (4) Considering the functional aspect of Korean costumes, their strong points were symetric beauty, rhythmical beauty, unity feeling, harmonical beauty and detailed decorations. Their common shortcomings were lack of individuality and inadequateness for active life. The shortcomings of woman costumes were suppressing breast, making resperation difficult and in adequnteness in summer time. The main reason not to wear our Korean costumes, was due to the fact that they are incomvenient for active life. As a measure to eliminate such shortcomings, 1) the suspension system of skirt to remove the suppression of breast should be generally adopted. 2) they should be simplified in their structure to make them convenient for active life and adepuate in wearing them in hot weather in an extent to which the traditional beauty of the costume may not be lostand 3) a new technique must be explored for showing individuality by wearing method and new arrangment of colors and decorations. (5) The reasons desiring to wear Korean costumes were classifide as follows: A. Korean costumes are our traditional clothes(43.4%). B. Korean costumes are noble and beautiful(26.8%). C. They are accustomed to wear Korean costumes by habit(19.5%). D. Korean costumes are necessary for attending ceremoneis(9.5%). E. Miscellaneous reasons(0.8%). Classifying these reasons into age groups, the high age group over 40 wore them because they were easy to wear by habit and the low age group of 10-30 never thought that they were east to wear by habit. Considering that even those who were accustomed to wear Korean costumes showed a low wearing rate and that the young generation were accustomed to wear Western style clothes rather than Korean costumes, the wearing rate of Korean costumes will be reduced in the future if such trend continues. It is urgent for us to make our best efforts in order to enhance the interest of young generation in Korean costumes and not to make them lose the strong points of Korean costume in the future. (6) Conicering the plan of the respondents on what kind of clothes they were going to wear in the future, among the age group over 50, those who wanted to wear only Korean costumes were 24.8%(men) and 35.1%(women), those who wanted to wear 49.7%(men) and 47.4(women), those who wanted to wear chiefly Western style clothes were 20.7% (men) and 14.4%(women) and those who wanted to wear only Western style clothes, were 2.4% (men) and 2.1%(women). This shows that the general tendency to wear only or chiefly Korean costumes is more prevalent than that to wear only Western style. Among the age group under 50, the tendency to wear Western style clothes was conspicuous and most of the respondent answered that they would wear chiefly Western style clothes and Korean costumes occasionally. Only 5.4% of the respondent answered that they would wear only Western style clothes and this shows that meny respondents still wonted to wear Korean costumes. Those who wanted their descendants to wear what they desire, were 50.1%(men) and 68.8% (women) and those who wanted their descendants to wear Koran costumes occasionally, were 85.8%(men) and 86.3%(women). This shows that most of respondents wanted their descendants to wear Korean costumes. In order to realize, it is necessory for us to make ourdescendants recognize the preciousness of our traditional culture and modify our Korean costumes according to their taste so that they may like wearing them.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.4
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• pp.343-354
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• 2010

The present study was conducted to examine the fermentation characteristics and effective degradability (ED) in the rumen, and whole tract digestibility of whole crop silage based TMR in comparison with conventional separate feeding of concentrate and roughage. Three ruminally fistulated non-lactating Holstein cattle were used in a 3 $\times$ 3 Latin square design. The cattle were fed 8kg of whole crop barley silage based TMR (BS-TMR) or 8kg (DM basis) of whole crop rye silage based TMR (RS-TMR) twice (08:00 and 18:00) daily in an equal amount. The cattle were also fed concentrate (5.6kg) and rice straw (1.4kg) seperately (DM basis, Control) twice daily in an equal amount. The both silages were included in TMR at 20% level (as fed basis). pH in the rumen fluid was not influenced by the diets but was slightly higher from TMR than from control. No difference was found in ammonia-N concentration between diets. Total VFA concentration was relatively increased in the cattle fed RS-TMR to the other diets up to 6h post feeding. The proportion of acetate was increased in the TMR feeding at right before feeding (0 h, p<0.005) and 9 h (p<0.048) post feeding compared with control. Propionate proportion was increased (p<0.046) in both TMRs while butyrate proportion was increased (p<0.029) at 1h post feeding compared to other diets. Effective degradability (ED) of DM and CP of RS-TMR was relatively increased to other diets, and EDNDF of both TMRs was higher than that of control diet due to the increased parameters b (p<0.039) and c (p<0.006) in TMR treatments. Whole track digestibility of most components in the TMRs was slightly increased compared to that in control diet, and RS-TMR had a tendency to be increased whole track digestibility except for NDF compared to BS-TMR. Based on the results observed from the present study, nutrient availability of whole crop silage based TMR looked slightly better than conventional separate feeding of concentrate and rice straw, mainly due to the improved stabilization of fermentation in the rumen and increased NDF digestibility of whole crop silage in TMR.

• Korean Journal of Poultry Science
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• v.39 no.2
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• pp.87-95
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• 2012

This experiment was conducted to investigate the effects of varying levels of metabolizable energy (ME) and crude protein (CP) on growth performance and carcass characteristics in layer-type growing male chicks. Nine hundred 1-d-old Hy-Line Brown male chicks were randomly allocated to 30 pens in a $2{\times}3$ factorial design. The experimental diets contained 2 levels of ME (2,800 kcal/kg and 2,950 kcal/kg) in combination with 3 levels of CP (17%, 18.5%, and, 20%). A significant interaction of ME and CP on feed intake was observed (p<0.05). No interaction was observed between ME and CP for 53 d BW gain or FCR, which improved linearly with dietary CP levels (p<0.05). A significant interaction or tendency was observed between ME and CP levels. The intake of ME for 1 g BW gain was linearly decreased with increasing CP levels (p<0.001). The intake of CP per bird was significantly increased in low ME (2,800 kcal/kg) treatment than that of the high ME treatment (2,950 kcal/kg) (p<0.05), and dietary CP level had more influence on CP intake for gram BW gain than level of ME. The relative weights of liver, spleen, breast meat and, leg were not influenced by the dietary treatments. Serum BUN, albumin, creatinine, and the activities of GOT and GPT were not influenced significantly by the diet treatment. In conclusion, the growth performance in layer-type male chicks was linearly increased when the level of dietary CP increased. The ME and CP did not affect the carcass characteristics and blood profiles. Therefore, the optimum levels of dietary ME and CP to improve the growth were 2,800 kcal/kg and above 18.5% in layer-type growing male chicks, respectively.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.3
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• pp.25-37
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• 1988

The purpose of this study is to fmd out the bask data for irrigation plans of tomato and chinese cabbage during the growing period, such as total amount of evapotranspiration, coefficients of evapotranspiration at each growth stage, the peak stage of evapotranspiration, the maximum evapotranspiration, optimum irrigation point, total readily available moisture and intervals of irrigation date. The plots of experiment were arranged with split plot design which were composed of two factors, irrigation point for main plot and soji texture for split plot, and three levels, irrigation points with PF 1.8, PF 2.2, PF 2.6 for tomato and those with PF 1.9, PF 2.3, PF 2.7, for Chinese cabbage, soil textures of silty clay, sandy loam and sandy soil for both tomato and Chinese cabbage, with two replications. The results obtained are summarized as follows 1. There was the highest significant correlation between the evapotranspiration and the pan evaporation, beyond all other meteoralogical factors considered. Therefore, the pan evaporation is enough to be used as a meteorological index measuring the quantity of evapotranspiration. 2. 1/10 probability values of maximum total pan evaporation during growing period for tomato and Chinese cabbage were shown as 355.8 mm and 233.0 mm, respectively, and those of maximum ten day pan evaporation for tomato and Chinese cabbage, 68.0 mm and 43.8 mm, respectively. 3. The time that annual maximum of ten day pan evaporation can be occurred, exists at any stage of growing period for tomato, and at any growth stage till the late of Septemberfor Chinese cabbage. 4. The magnitude of evapotranspiration and of its coefficient for tomato and Chinese cabbage was occurred in the order of pF 1.8>pF 2.2>pF 2.6 and of pF 1.9>pF 2.3>pF 2.7 respectively in aspect of irrigation point and of silty clay>sandy loam>sandy soil in aspect of soil texture. 5. 1/10 probability value of evapotranspiration and its coefficient during the growing period of tomato were shown as 327.3 mm and 0.92 respectively, while those of Chinese cabbage, 261.0 mm and 1.12 respectively. 6. The time that maximum evapotranspiration of tomato can be occurred is at the date of fortieth to fiftieth after transplanting and the time for Chinese cabbage is presumed to he in the late of septemben At that time, 1/10 probability value of ten day evapotranspiration and its coefficient for tomato is presumed to be 74.8 mm and 1.10 respectively, while those of Chinese cabbage, 43.8 mm and 1.00. 7. In aspect of only irrigaton point, the weight of raw tomato and Chinese cabbage were mcreased in the order of pF 2.2>pF 1.8>pF 2.6 and of pF 1.9>pF 2.3>pF 2.7, respectively but optimum irrigation point for tomato and Chinese cabbage, is presumed to be pF 2.6 - 2.7 if nonsignificance of the yield between the different irrigation treatments, economy of water, and reduction in labour of irrigaion are synthetically considered. 8. The soil moisture extraction patterns of tomato and Chinese cabbage have shown that maximum extraction rate exists at 7 cm deep layer at the beginning stage of growth m any soil texture and that extraction rates of 21 cm to 35 cm deep layer are increased as getting closer to the late stage of growth. And especially the extraction rates of 21 cm deep layer and 35 cm deep layer have shown tendency to be more increased in silty clay than in any other soils. 9. As optimum irrigation point is presumed to be pF Z6-2.7, total readily available moisture of tomato in silty clay, sandy loam and sandy sofl becomes to be 19.06 mm, 21.37 mm and 20.91 mm respectively while that of Chinese cabbage, 18.51 mm, 20.27 mm, 21.11 mm respectively. 10. On the basis of optimum irrigation point with pF 2.6 - 2.7 the intervals of irrigation date of tomato and Chinese cabbage at the growth stage of maximum consumptive use become to be three days and five days respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.6
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• pp.823-829
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• 2016

Eight Holstein steers ($216{\pm}48kg$ body weight) fitted with ruminal and duodenal cannulas were used to evaluate effects of wheat straw processing (ground vs pelleted) at two straw inclusion rates (7% and 14%; dry matter basis) in dry rolled or steam-flaked corn-based finishing diets on characteristics of digestion. The experimental design was a split plot consisting of two simultaneous $4{\times}4$ Latin squares. Increasing straw level reduced ruminal (p<0.01) and total tract (p = 0.03) organic matter (OM) digestion. As expected, increasing wheat straw level from 7% to 14% decreased (p<0.05) ruminal and total tract digestion of OM. Digestion of neutral detergent fiber (NDF) and starch, per se, were not affected (p>0.10) by wheat straw level. Likewise, straw level did not influence ruminal acetate and propionate molar proportions or estimated methane production (p>0.10). Pelleting straw did not affect ($p{\geq}0.48$) ruminal digestion of OM, NDF, and starch, or microbial efficiency. Ruminal feed N digestion was greater (7.4%; p = 0.02) for ground than for pelleted wheat straw diets. Although ruminal starch digestion was not affected by straw processing, post-ruminal (p<0.01), and total-tract starch (p = 0.05) digestion were greater for ground than for pelleted wheat straw diets, resulting in a tendency for increased post-ruminal (p = 0.06) and total tract (p = 0.07) OM digestion. Pelleting wheat straw decreased (p<0.01) ruminal pH, although ruminal volatile fatty acids (VFA) concentration and estimated methane were not affected ($p{\geq}0.27$). Ruminal digestion of OM and starch, and post-ruminal and total tract digestion of OM, starch and N were greater (p<0.01) for steam-flaked than for dry rolled corn-based diets. Ruminal NDF digestion was greater (p = 0.02) for dry rolled than for steam-flaked corn, although total tract NDF digestion was unaffected (p = 0.94). Ruminal microbial efficiency and ruminal degradation of feed N were not affected (p>0.14) by corn processing. However, microbial N flow to the small intestine and ruminal N efficiency (non-ammonia N flow to the small intestine/N intake) were greater (p<0.01) for steam-flaked than for dry rolled corn-based diets. Ruminal pH and total VFA concentration were not affected ($p{\geq}0.16$) by corn processing method. Compared with dry rolled corn, steam-flaked corn-based diets resulted in decreased acetate:propionate molar ratio (p = 0.02). It is concluded that at 7% or 14% straw inclusion rate, changes in physical characteristics of wheat straw brought about by pelleting negatively impact OM digestion of both steam-flaked and dry-rolled corn-based finishing diets. This effect is due to decreased post-ruminal starch digestion. Replacement of ground straw with pelleted straw also may decrease ruminal pH.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.8
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• pp.1189-1195
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• 2008

A study was conducted with 48 weaned barrows ($28{\pm}3d$, $8.45{\pm}0.14kg$) to determine the effect of Achyranthes bidentata polysaccharide (ABPS) supplementation on pig performance, immunological, adrenal and somatotropic responses following Escherichia coli lipopolysaccharide (LPS) challenge. The experiment was a $2{\times}2$ factorial design; the main factors included diet (supplementation with 0 or 500 mg/kg ABPS) and immunological challenge (LPS or saline). On d 14 and 21 of the trial, pigs were given an intraperitoneal injection with either $100{\mu}g/kg$ BW of LPS or an equivalent amount of sterile saline. Blood samples were obtained 3 h after injection for analysis of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), prostaglandin $E_2$ ($PGE_2$), cortisol, growth hormone (GH), insulin-like growth factor (IGF)-I and immunoglobulin G (IgG). On d 2 after LPS challenge, peripheral blood lymphocyte proliferation (PBLP) was measured. LPS administration decreased average daily feed intake (ADFI) (p<0.05), had a tendency to decrease average daily gain (ADG) (p<0.10) during both the first and second challenge periods and increased (p<0.05) feed:gain ratio only during the first challenge period. ABPS tended to improve ADG (p<0.10) during the first challenge period, and improved ADG (p<0.05) and tended to improve ADFI (p<0.10) during the second challenge period. ABPS did not affect feed:gain ratio. An interaction (p<0.05) between LPS challenge and diet was observed for the plasma concentrations of TNF-${\alpha}$, $PGE_2$ and cortisol after both LPS challenges such that, among LPS-treated pigs, pigs fed the ABPS diet were lower for these indices than those receiving the control diet. In contrast, pigs fed the ABPS diet had higher IGF-I (p<0.05) compared with those fed the control diet. No effect of diet, LPS challenge or both on GH and IgG was observed after both LPS administrations. LPS challenge increased PBLP when these cells were incubated with $8{\mu}g/ml$ of LPS during both the challenge periods, and did likewise when incubated with $8{\mu}g/ml$ of concanavalin A only after the first challenge. ABPS had no effect on PBLP. These data demonstrate that ABPS alters the release of pro-inflammatory cytokines following an immunological challenge, which might enable pigs to achieve better performance.