• Journal of Animal Environmental Science
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• v.17 no.sup
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• pp.7-20
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• 2011

This study was conducted to analyze the mixing ratio of raw feed materials for the methane mitigation and also to identify the minimum rearing density for improving the productivity of beef calves as eco-friendly fodder. Raw materials used in this study for the formulation of feed for methane reduction were crushed corn and alfalfa along with other 21 species. In addition, to investigate the appropriate rearing density, 12 Hanwoo calves with average weight of 150 kg was selected and experiment was conducted for four months. Methane gas emission (Bo) is about 3-4 times less in TMR 4 compared to TMR 1, 2 and 3. Feed price calculated for TMR 4 ration was also affordable. In addition, all TMRs showed a normal ruminal pH. Disappearance rate was observed to be lower in TMR 4 as compared to TMR 1, 2 and 3, but methane production decreased by 24 to 37%. The result showed improved total body weight, average daily gain and feed conversion ratio in rearing low-density ($18m^2/head$), and general treatment ($9m^2/head$) compared to overcrowding treatment ($6m^2/head$). In addition, blood components (total protein, glucose, AST, ALT and GGT factors) involved in health and disease treatments and health-related nutrition metabolism are lower in the low-density and general treatment compared to the high density treatment. Postural development (development of body size) i.e., weight, height and width significantly increased in the low and general density treatment compared to high density treatment. Especially excellent improvement was observed in low-density treatment than the general treatment. Moisture content, colonic bacteria and coccidium are higher in low and high density treatments than in the general treatment. The adequacy for beef rearing density is considered to be more desirable in an area more than $6m^2/head$. In conclusion, present study suggests that possibility of methane reduction through adjusting mixed feed ration. Also, rearing density is also an important factor in the growth and development of beef calves.

• Korean Journal of Environment and Ecology
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• v.24 no.2
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• pp.157-165
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• 2010

This study was carried out to suggest the basic data of planting method for construction of buffer green space based on the land use in case of reclaimed land by analyzing land structure, planting concept, and planting structure in buffer green space, Rokko Island, Kobe, Japan. Rokko Island(total area: 580ha) is divided into port and logistics industry area and urban area by constructing the box type large-scale buffer green space. The land structure of buffer green space were biased mounding type, parallel mounding type, and complex mounding type. The width of buffer green space was 50meters in case of northern area, from 28 to 32meters in case of eastern area, and 37.5meters in case of western area, and the slope of that was from 18 to 25 degrees and the height of that was from 2 to 15meters. There were applied landscape and buffer planting concept on the sea side area of northern buffer green space, on the other hand landscape and shade planting concept on the Inner city side area of that. According to the result of planting structure analysis of northern buffer green space, the main woody species were those of deciduous-evergreen species grow in warm-temperate forest zone such as Quercus glauca, Cinnamomum camphora, Machilus thunbergii, Elaeagnus maritima. The results of maximum number of species and planting density by $100mm^2$ was that 9 species 22 individuals in canopy layer, 9 species 15 individuals in understory layer, 3 species 67 individuals in shrub layer, and 14 species 104 individuals in total. The plant coverage of northern buffer green space based on the ecological planting method was from 69 to 139% in case of canopy layer, from 26 to 38% in case of understory layer, from 6 to 7% in case of shrub layer, and from 101 to 184% in total. Index of plant crown volume of northern buffer green space based on the ecological planting method was from 1.40 to $3.12m^3/m^2$ in case of canopy layer, from 0.43 to $0.55m^3/m^2$ in case of understory layer, $0.06m^3/m^2$ in case of shrub layer, and from 1.89 to $3.73m^3/m^2$ in total.

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.148-157
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• 2014

The purpose of this study was to investigate greenhouse maintenance by farms by looking into greenhouses across the nation for greenhouse specification, disaster-resistance greenhouse construction, types and degree of damage due to natural disasters, pre-inspection in case of typhoon or heavy snow forecast, and fire-fighting facilities to prevent a fire. The findings were summarized as follows: as for greenhouse specification, the highest proportion of them were 90 m or longer both in single- and multi-span greenhouses in terms of length; 8 m or wider and 7.0~7.9 m in single- and multi-span greenhouses, respectively, in terms of width; 1.5~1.9 m and 2.0~2.9 m in single-and multi-span greenhouses, respectively, in terms of height; and 3.0~3.9 m and 6 m in single- and multi-span greenhouses, respectively, in terms of diameter. As for disaster-resistance greenhouses, farmers were reluctant to install such greenhouses. The low distribution of disaster-resistance greenhouses was attributed to the greenhouses built dependent on the old practice, the greenhouses already completed, and relatively high construction costs. As for damage by natural disasters, greenhouses were subject to more damage by typhoons than heavy snow. They mainly inspected the ceiling and side windows, entrances, and fixation bands for covering materials in case of typhoon forecast and the heating devices in case of heavy snow forecast. As for repair methods for greenhouse pipe corrosion, they preferred partial replacement to painting and did not use stiffeners for structures to prevent a natural disaster in most cases. As for the maintenance of greenhouse covering materials, most farmers inspected their sealing property but did not clean the coverings for light transmission. The destruction of structural materials can be prevented by eliminating greenhouse covering materials during a typhoon, but they were not able to do so because of the covering material replacement costs and the crops they were growing. The study also examined whether greenhouse farms had fire-fighting facilities to prevent a fire and found that they lacked the perception of greenhouse fire prevention to a great degree.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.1 no.1
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• pp.3-17
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• 1998

The purposes of this study is to investigate the possibility of planting trees at space land in the riverside. The space land is for the green space. Calculating the plantable space in the representation section and the flood flowing stability of the existing banks based on the hydrological and meteorological data of the Kap-Chon riverbasin located in Tae-jon, the following results are drawn. (1) The flood discharges in each flow section are $698.7m^3/s$ in section 1, $654.6m^3/s$ in section 2, and $1353.3m^3/s$ in section 3 during 100 years recurrence interval. Because the designed-flood discharges in those sections are $1719.9m^3/s$, $2119.7m^3/s$, and $1512.8m^3/s$ respectively, safety for flood flowing is sufficient in existing banks. (2) The possible clearance for planting trees is 1.80m in section 1, 3.90m in section 2, and 0.01m in section 3. Planting clearance is enough in section 1 and 2. However, planting should be planned after estimating a rise-height due to the bridge piers, because many piers under riverine-highway are now on the construction in section 2. The section 3 does not have sufficient clearance for planting trees, but the planting is possible after getting enough flow area with slope by cutting the terrace land on the river artificially heightened. (3) In case of planting a tree 70cm diameter in $1m^2$ in section 1, the water level increases by 0.60m. Planting a tree in a $48m^2$ area increases the water level by 0.90m. Considering that plantable clearance is 1.8m in section 1, it is sufficient to flow safely. But if the trees are planted so compactly from the upper stream, expected heavy resistance is expected due to caught materials on the trees. So, trees have to be planted widely in upper streams but compactedly in lower streams. (4) The river width without changing, Kap-Chon's flow channel can be snaked in accordance with the nature law the wide terrace land in the riverside. Decreased flow area due to planting trees will be compensated by the inclination of terrace land. And, it is theoretically proved that the flood discharge is safe even though the terrace land on the river is parked similar to the nature. Planting trees in the terrace land of the Kap-chon river to the extent that flood flowing is not adversely affected, we can get the enjoyable park to citizens not spending expensive cost. It also contributes to the recovery of ecosystem, which gives the natural beauty of river and shade to citizens and becomes good natural-educational places for children.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.349-354
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• 2013

This study examined a technique for cooling root zone aimed at lowering substrate temperature for sweet pepper (Capsicum annum L. 'Orange glory') cultivation in coir substrate hydroponics during hot season, from the $16^{th}$ of July to $15^{th}$ of October in 2012. The root zone cooling technique was applied by using an air duct (${\varnothing}12$ cm, hole size 0.1 mm) to blow cool air between two slabs during night (5p.m. to 3a.m.). Between the $23^{rd}$ of July and $31^{st}$ of August (hot temperature period), average daily substrate temperature was $24.7^{\circ}C$ under the root zone cooling, whereas it was $28.2^{\circ}C$ under condition of no cooling (control). In sunny day (600~700 W $m^{-2}{\cdot}s^{-1}$), average substrate temperatures during the day (6a.m. to 8p.m.) and night (8p.m. to 6a.m.) were lower about $1.7^{\circ}C$ and $3.3^{\circ}C$, respectively, under the cooling treatment, compared to that of control. The degree of temperature reduction in the substrate was averagely $0.5^{\circ}C$ per hour under the cooling treatment during 6p.m. to 8p.m.; however, there was no decrease in the temperature under the control. The temperature difference between the cooling and control treatments was $1.3^{\circ}C$ and $0.6^{\circ}C$ in the upper and lower part of the slab, respectively. During the hot temperature period, about 32.5% reduction in the substrate temperature was observed under the cooling treatment, compared to the control. Photosynthesis, transpiration rate, and leaf water potential of plants grown under the cooling treatment were significantly higher than those under the control. The first flowering date in the cooling was faster about 4 days than in the control. Also, the number of fruits was significantly higher than that in the control. No differences in plant height, stem thickness, number of internode, and leaf width were found between the plants grown under the cooling and control, except for the leaf length with a shorter length under the cooling treatment. However, root zone cooling influenced negligibly on eliminating delay in fruiting caused by excessively higher air temperature (> $28^{\circ}C$), although the substrate temperature was reduced by $3^{\circ}C$ to $5.6^{\circ}C$. These results suggest that the technique of lowering substrate temperature by using air-duct blow needs to be incorporated into the lowering growing temperature system for growth and fruit set of health paprika.

• Publications of The Korean Astronomical Society
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• v.36 no.3
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• pp.65-78
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• 2021

Jagyeokru, an automatic striking water clock described in the Sejong Sillok (Veritable Records of King Sejong) is essentially composed of a water quantity control device and a time-signal device, with the former controlling the amount or the flow rate of water and the latter automatically informing the time based on the former. What connects these two parts is a signal generating device or a power transmission device called the 'Jujeon' system, which includes a copper rod on the float and ball-racked scheduled plates. The copper products excavated under Gongpyeong-dong in Seoul include a lot of broken plate pieces and cylinder-like devices. If some plate pieces are put together, a large square plate with circular holes located in a zigzag can be completed, and at the upper right of it is carved 'the first scheduled plate (一箭).' Cylinder-like devices generally 3.8 cm in diameter are able to release a ball, and have a ginkgo leaf-like screen fixed on the inner axis and a bird-shaped hook of which the leg fixes another axis and the beak attaches to the leaf side. The lateral view of this cylinder-like device appears like a trapezoid and mounts an iron ball. The function of releasing a ball agrees with the description of Borugak Pavilion, where Jagyeokru was installed, written by Kim Don (1385 ~ 1440). The other accounts of Borugak Pavilion's and Heumgyeonggak Pavilion's water clocks describe these copper plates and ball releasing devices as the 'Jujeon' system. According to the description of Borugak Pavilion, a square wooden column has copper plates on the left and right sides the same height as the column, and the left copper plate has 12 drilled holes to keep the time of a 12 double-hours. Meanwhile, the right plate has 25 holes which represent seasonal night 5-hours (Kyeong) and their 5-subhours (Jeom), not 12 hours. There are 11 scheduled plates for seasonal night 5-hours made with copper, which are made to be attached or detached as the season. In accordance with Nujutongui (manual for the operation of the yardstick for the clepsydra), the first scheduled plate for the night is used from the winter solstice (冬至) to 2 days after Daehan (大寒), and from 4 days before Soseol (小雪) to a day before the winter solstice. Besides the first scheduled plate, we confirm discovering a third scheduled plate and a sixth scheduled plate among the excavated copper materials based on the spacing between holes. On the other hand, the width of the scheduled plate is different for these artifacts, measured as 144 mm compared to the description of the Borugak Pavilion, which is recorded as 51 mm. From this perspective, they may be the scheduled plates for the Heumgyeonggak Ongru made in 1438 (or 1554) or for the new Fortress Pavilion installed in Changdeokgung palace completed in 1536 (the 31^st year of the reign of King Jungjong) in the early Joseon dynasty. This study presents the concept of the scheduled plates described in the literature, including their new operating mechanism. In addition, a detailed model of 11 scheduled plates is designed from the records and on the excavated relics. It is expected that this study will aid in efforts to restore and reconstruct the automatic water clocks of the early Joseon dynasty.

• Korean Journal of Heritage: History & Science
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• v.44 no.4
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• pp.142-153
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• 2011

'Silla Monument Stone in Jungseong-ri, Pohang' was discovered in Pohang City, Gyeongsangbuk Province of Korea in 2009. The monument stone with irregular shape has dimensions of maximum height of 105cm, width of 47.6~49.6cm, thickness of 13.8~14.7cm and weight of 115kg. The results of monument stone was found to be granitite. Conservation treatment procedure was carried out in the order of production of Weathering map, cleaning of surface pollutants, consolidation using ethyl silicate. Black pollutant(crust) that covered more than 60% of the surface was analyzed first in order to remove the pollutants on the surface of the monumental stone by cleaning of surface pollutants using laser. The purpose on analysis was not only to verify the pollutants on the stone but also to carry out preliminary cleaning by securing rocks with same pollutant as the monumental stone. As the results of analysis using p-XRF(PMI. INNOV-X, USA) on the site, high level of Mn and Fe were detected, and the analysis of small section that had been fallen off with SEM/EDX for the purpose of quantitative analysis also detected high level of Mn. The Similar contaminants on Stone secured in the manner described above were made into 10 samples ($5cm{\times}5cm$) and was subjected to preliminary cleaning by Nd-YAG Laser(Laser&Physics, Korea). The results of surface observation through portable microscope during cleaning revealed that the power of 460mJ, wavelength of 1064nm and irradiation frequency of 1,800~2,300 per $25cm^2$ were most effective. Evaluation on the preservative treatment was made through confirmation of the extent of removal through color-difference meter measurement and component analysis prior to and following removal of the pollutants. As the result of color-difference meter measurement increase in the brightness was evidenced by the increase in the brightness ($L^*$)value from 33 to 49, and it was possible to ascertain the reduction in the pollutants as the content of Mn was reduced by about 80% from $50,000{\pm}5,000ppm$ to $10,000{\pm}2,000pmm$ from the result of component analysis.

• Journal of Bio-Environment Control
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• v.32 no.3
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• pp.249-255
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• 2023

Korean melon (Cucumis melo L.) is grown mostly in Northeast Asia area, and as a fruit mainly produced in Korea, the yield per unit area continues to improve, but the cultivation method is limited to soil cultivation, so it is necessary to develop hydroponic cultivation technology for scale and labor-saving is needed. As the ratio of NO₃^- increased, the plant height, the leaf length, the leaf width, and the internode length became longer and larger. On the other hand, the SPAD value decreased. The lower the ratio of NO₃^-, the faster the female flower bloom, and there was no difference in fruit maturity between treatments. There was no difference in the shape of fruit according to the ratio of NO₃^-, and the hardness was higher as the ratio of NO₃^- was lower. The total yield from March to July was KM3 5,650 kg/10a and KM1 4,439 kg/10a, 27% higher in KM3 and, in particular, 36% higher in quantity from March to May, when Korean melon prices were high season. Therefore, it was judged that it would be appropriate to supply NO₃^- suitable for hydroponic cultivation of Korean melon, which was formalized in December and produced from spring, at the level of 6.5 to 10 me·L^-1.

• Archives of design research
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• v.16 no.3
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• pp.319-328
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• 2003

The purpose of this study was to investigate the actual size of tables and chairs in small restaurants. The examined objets were 48 restaurants serving flour-based, korean style and japanese style meals. Those restaurants are currently being operated at six universities in Seoul, and their sizes are limited under $66m^2$. The results of this study were as follows ; 1 . In small restaurants, the size of the seat for one person is $0.346m^2$on the average. The range of the size starts from $0.285m^2$to $0.403m^2$, showing a great difference. 2. The most common size of tables in small restaurants is the oblong style of $600{\times}900$ for four people. The smallest size is $440{\times}710$, while the biggest one is $700{\times}1000$, showing a great number of variation. If the most common size of tables is set to be the general size of tables in small restaurants, it will be $600{\times}900$. 3. The sizes of the seats for chairs used in small restaurants start from $270{\times}270$ to $430{\times}430$. The most common size of the seats for chairs is $400{\times}400$, only showing a small number. For the cases of tables with the most common size of $600{\times}900$, the width of the seats for chairs should be under 400. 4. For the height between the table and the seats of the chair, the distance from 270 to 300 is relevant. However, according to the results of the investigation, it seems that there are more cases of the distance from 250 to 260 than that from 270 to 300.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.4
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• pp.233-238
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• 1978

Rainbow trout were reared in a stainless steel aquarium from Nov. 11, 1977 to June 12, 1978, and the following results were obtained : 1. The volume of water was about $400\iota$ in a aquarium measuring $1m\;(Length)\times1m\;(Width)\times67cm(Height)$ and water depth 40 cm. Water was supplied for about 16 hours daily at a rate $3\iota/min$ and was drained through the conical settling part in the middle of the aquarium bottom. Filter tank was about $23cm(W)\times23cm(L)\times40cm(D)$ and contained pebbles 30 cm in depth. Water recirculation rate was at)out $1,030\iota/hr$, or 2.6 turn-over per hour. 2. During the first period (77 days), the trout grew from 88.3g to 229g in average, the total weight attaining 30.7kg. The food coefficient was 1.249, average daily increment 243.3g, average daily growth rate 1.245%, and the mortality was 2 smallest fish weighing 53 g, owing to unknown reason. During the second period (135 days), the trout grew from 239g to 555g in average, the total weight attaining 57.2 kg. The food coefficient was 1.447, average daily increment 279.8g, average daily growth rate $0.65\%$ and the mortality was 31 fish weighing 11,255 g, owing partly to miss-handling and partly to disease. 3. The feed consisting of fully domestic materials was prepared in this laboratory, and the feed conversion was not inferior to high protein commercial feed available in foreign countries. 4. The result of whole period for 212 days was 56.5 kg in gross increment, and based on this result, when $1\iota/min$ full day inflowing water available, the net production will become 28.25 kg. So, if a 5000kg production is planned, $180\iota/min$ or about $10.8m^3/hr$ be reauired, and the production in value frill become 15million won at local price at the expense of about 5.3 million won. From the result of this experiment, rainbow trout is feasible for commercial production in Korea with relatively small amount of well water and simplified water recirculation system.