• Asian-Australasian Journal of Animal Sciences
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• v.19 no.5
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• pp.699-704
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• 2006

Twenty-four cannulated Small-tailed Han${\times}$Poll Dorset wethers (BW $47.5{\pm}2.1kg$) were used to determine the effects of forage to concentrate ratio (40:60 vs. 70:30), monensin supplementation (0, 15 or 30 ppm, DM basis) and interactions of these two factors on cis-9, trans-11 conjugated linoleic acid (cis-9, trans-11 CLA) and trans-11 octadecenoic acid (trans11-$C_{18:1}$) concentrations in ruminal contents and plasma in sheep. The experiment was designed as a $2{\times}3$ factorial. The diet contained Chinese wild rye grass hay (Aneurolepidium Chinese), cracked corn, soybean meal, NaCl, limestone and trace mineral premix. Dietary crude fat and linoleic acid ($C_{18:2n-6}$) were adjusted with soybean oil to about 7.0% and 24.0 mg/g (DM basis), respectively. High forage diets increased (p<0.001) the concentrations of trans11-$C_{18:1}$ and cis-9, trans-11 CLA in ruminal contents and plasma. Monensin supplementation increased (p<0.001) the concentration of trans11-$C_{18:1}$ in ruminal contents, but had no effect on that of cis-9, trans-11 CLA. Concentrations of trans11-$C_{18:1}$ (p<0.019) and cis-9, trans-11 CLA (p<0.022) in plasma increased with dietary monensin levels. Interactions of forage: concentrate ratio and monensin level tended to affect the concentrations of trans11-$C_{18:1}$ (p<0.091) and $C_{18:2n-6}$ (p<0.083) in ruminal contents. Increasing forage levels increased the concentrations of trans11-$C_{18:1}$ and cis-9, trans-11 CLA in the rumen. Supplementing with monensin increased the ruminal production of trans11-$C_{18:1}$ and concentrations of trans11-$C_{18:1}$ and cis-9, trans-11 CLA in plasma.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.10
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• pp.1441-1448
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• 2008

This experiment was carried out to study the carcass characteristics, chemical composition and fatty acid profile of the Longissimus muscle (LM) of bulls (10) and steers (17) finished in a pasture system. Animals (1/2 Zebu vs. 1/2 Aberdeen Angus) were fed in a pasture system (Hermatria altissima) and with a supplement of soybean meal, cracked corn, urea, limestone and mineral salts, twice a day. Both animal groups were slaughtered at 27 months of age, with an average 508.88 kg of live weight. Final weight, hot carcass weight and texture were similar (p>0.05) between bulls and steers. Carcass dressing, fat thickness, color and marbling were higher (p<0.02) in steers. Conversely, the Longissimus area was greater (p<0.05) in bulls. Moisture levels were higher (p<0.01) in bulls. Ash, crude protein, total lipids and total cholesterol levels were higher (p<0.10) in steers. C14:0, C16:0, C16:1 n-7 and C18:1 n-9 fatty acids percentages were higher (p<0.06) in steers. C16-1 n-10, i 17:0, C19:0, C18:2 n-6, C18:3 n-3, C20:2 n-3 C20:4 n-6, C20:5 n-3, C22:1 n-7, C22:4 n-6 and C22:5 n-3 fatty acids percentages were higher (p<0.05) in bulls. The percentage of the other fatty acids was similar (p>0.05) in bulls and steers. The levels of monounsaturated fatty acids were higher (p<0.02) in steers while polyunsaturated fatty acids, n-3, n-6, PUFA/SFA and n6:n3 ratios, were higher (p<0.05) in bulls. The CLA contents (mg/g lipids) were similar (p>0.10) in bulls and steers.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.8
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• pp.1131-1138
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• 2004

The objective of this study was to investigate the effects of different sources of Ca and P on urine and ileal digesta pH, and ammonia ($NH_{3}$), methane ($CH_{4}$), and odor emission. In experiment 1, eight pigs (commercial three-way cross; initial BW 67$\pm$3 kg) were arranged in a repeated 4$\times$4 Latin Square design. All pigs were equipped with a T-cannula in the distal ileum. Four corn-soybean meal based diets were formulated. Diet 1 was the control in which dicalcium phosphate (DCP) and limestone ($CaCO_{3}$) were used as the sources of inorganic P and Ca. In Diets 2 and 3, ${H_{3}}{PO_{4}}$, monocalcium phosphate (MCP), and $CaSO_{4}$replaced DCP and $CaCO_{3}$ as the inorganic sources of P and Ca. Diet 4 was similar to Diet 1 except that it was fortified with HCl to provide an acid load similar to that of diet 2. Urine and ileal digesta pH were determined in pigs fed each of these diets. In Exp. 1, urine pH decreased (p<0.05) in animals consuming diets containing ${H_{3}}{PO_{4}}$-$CaSO_{4}$ (5.85$\pm$0.38) and MCP-$CaSO_{4}$(5.73$\pm$0.30) compared with the DCP-$CaCO_{3}$ diet (6.89$\pm$0.24). In the pigs consuming ${H_{3}}{PO_{4}}$-$CaSO_{4}$, ileal digesta pH decreased compared with the control (5.52$\pm$0.28 vs. 6.66$\pm$0.17; p<0.05). Based on the results of Exp. 1, a total of four trials were performed in environmental chambers for determining how $NH_{3}$, $NH_{4}$, and odor were affected by the different dietary Ca and P sources (Exp. 2). In Exp. 2, pigs fed the ${H_{3}}{PO_{4}}$-$CaSO_{4}$ diet had decreased (30%) $NH_{3}$ emissions compared with the control (p<0.05). Also, a combination of MCP-$CaCO_{3}$-$CaCl_{12}$ decreased $NH_{3}$ emission by 15% (p<0.05). Emission of $CH_{4}$ was decreased only with the ${H_{3}}{PO_{4}}$-$CaSO_{4}$ diet with 14% (p<0.05). Odorant emission of phenolics and volatile fatty acids increased roughly three-fold with the DCP-$CaSO_{4}$ diet but was not affected by other test diets. In conclusion, acidogenic Ca and P sources in swine diets can decrease the urinary pH and reduce $NH_{3}$ and $CH_{4}$ emission from swine facilities.

• Journal of the Korean association of regional geographers
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• v.1 no.1
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• pp.93-101
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• 1995

Nam Khane watershed, in the Northern Laos, consists of limestone plateau surrounded with steep slope(above 1000m), wide piedmont hill land(300-700m) and narrow alluvial plain. Opium on the plateau and up-land rice on the hill-side are cultivated for each, but its shifting agricultural activity, which degrades the forest and soil, has caused the serious environmental problems. MOS-1 satellite image and 40 points of soil samples are analyzed to identify the distribution of the shifting cultivation and to evaluate the environmental problems for Nam Khane watershed. The land use classification map is presented on the photo 2, and the value of each land use area by elevation level and soil property are showed on the table 2 and 3, respectively. Excessive agricultural activity of shifting cultivation in the Nam Khane watershed not only decreased the forest area, but also changed the primary forest of tree into secondary woodland of shrub. On the phase of soil property, it accelerated the soil and gully erosion, and acidification. To solve these environmental problems, the most important step is to settle the agriculture from shifting cultivation to permanent cropping.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.545-552
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• 2017

Ground subsidence can result in the formation of sinkholes, potholes, settlement of structures, and road subsidence. Road subsidence is described as the sudden collapse of the road surface into subsurface cavities caused by the loss of bearing capacity in the ground, such as the dissolution of limestone by fluid flow in the surface causing the formation of voids leading to subsidence at the surface. Road subsidence occurs about 665 times annually, and this incidence has been increasing until 2013. Damaged underground facilities, management negligence, and lowering of the ground water table have been the causes of road subsidence in Seoul. Seoul metropolitan government announced special management counter plans to relieve the anxieties and make the roads safe for passing. Construction sites, such as excavation works, need to be managed properly because they have strong potential to induce road subsidence. The aim of this study was to identify the main causes of road subsidence and suggest management plans. First, life cycle cost analysis revealed the daytime construction to be more appropriate than nighttime. In addition, by analyzing the limitations of using sand as a backfill material, it is proposed to use a flowable backfill material instead of sand. Finally, to reduce the blind spots, which is a problem in surveying the road pavement conditions of local governments, the road to be managed is divided into several zones, and a specialized agency is selected for each zone and a method of surveying the blind spots through collaboration is suggested.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.2
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• pp.116-123
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• 2014

The description of vegetation cover and floral composition was undertaken in terms of phytosociological study in Dodamsambong(scenic site no. 44) and Danyangseokmoon(no. 45). In this study a total of 17 $relev{\acute{e}}s$ containing 144 taxa were collected and analyzed. Eight plant communities are differentiated, grouped into 4 physiognomic types: forest type(Buxus microphylla var. koreana-Thuja orientalis community, Tilia mandshurica-Quercus variabilis community, and Cynanchum wilfordii-Pinus densiflora community), mantle type(Cardamine leucantha-Neillia uekii community), secondary meadow type(Galium kinuta-Spodiopogon sibiricus community, Diarthron linifolium-Zoysia japonica community), and crevice type(Patrinia rupestris-Selaginella stauntoniana community, Hypodematium glandulosopilosum community). The vegetation of Dodamsambong and Danyangseokmoon is characterized by local flora, such as calciphilous plants, geological distribution-limit species, and endemic species. The soil depth, slope, and human impact have been identified as the most important differentiating ecological factors. Buxus microphylla var. koreana-Thuja orientalis community, Tilia mandshurica-Quercus variabilis community, and Patrinia rupestris-Selaginella stauntoniana community were evaluated highly by National Vegetation Naturalness. In order to restore the value of specific landscape for scenic site, we should improve the problems of protected area such as wrong management on habitat, forest fragmentation by facilities and decline in vegetation by lack of growing the next succession.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.44-52
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• 1996

Humic substances of 17 organic fertilizers available on the market were the objects of study. The list of ingredients for formulation of them comprised fish meal. bone meal, oil-cakes, brewer's grains, peat, sawdust, wood bark, zeolite, soil conditioner, live-stock droppings, amino acid fermentation byproduct, chaff, limestone and others. Humic and fulvic acids were isolated from those substances and given chemical and spectroscopic analyses. Nutritional values of the organic fertilizers showed big diversity. Humification of organic matter was incomplete for some of the fertilizers as indicated by a high C/N ratio. Extractable humic acid percentage was higher, in general, than that of fulvic acid. Also the relative content of humin increased with advanced humification. Total acidity was closely related to phenolic hydroxyl groups. Relationships between carboxyl and hydroxyl groups. and carboxyl and alcoholic hydroxyl groups were very significant. Ultraviolet and visible light absorption spectra of humic and fulvic acids were substantially similar. The types of humic acids were B. P, and Rp. Two humic acids of the 17 samples belonged to B type. 3 to P type and all the rest to Rp type.

• Journal of the Korean Ceramic Society
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• v.40 no.8
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• pp.804-810
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• 2003

The fine powder produced by heating and grinding of the waste concrete in the waste construction was investigated whether utilize as substitution raw material of SiO$_2$, CaO, and Al$_2$O$_3$ source for OPC clinker manufacture is possible or not. In order to synthesize OPC clinker, limestone, shale, converter slag and fly ash were used as main raw materials, and modulus was fixed LSF 91.0, SM 2.60, IM 1.60. The synthesized clinkers were characterized. The Main products of synthesized clinker were C$_3$S, ${\beta}$-C$_2$S, C$_3$A, C$_4$AF as OPC clinker at 1,43$^{\circ}C$. As a result of TG-DTA and burnability index(B.U) analysis of each raw mixtures, the formation temperature of clinker phases was similar and B.I was showed easy burning as 48.6∼51.4.

• Journal of the Korean Ceramic Society
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• v.53 no.2
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• pp.194-199
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• 2016

Presently, for the cement industry, studies that seek to reduce $CO_2$, because of the development of the plastic industry and demand for reduction of energy use, have been actively conducted among them, studies attempting to use Gamma-$C_2S({\gamma}-C_2S)$ to fix $CO_2$ have been actively conducted. The ${\gamma}-C_2S$ compound has an important function in reacting to $CO_2$ and stiffening through carbonatization in the air. The ${\gamma}-C_2S$ compound, reacting to $CO_2$ in the air, generates $CaCO_2$ within the pore structure of cement materials and densifies the pore structure this leads to an improvement of the durability and to the characteristic of resistance against neutralization. Therefore, in this experiment, in order to synthesize ${\gamma}-C_2S$, limestone sludge and waste foundry sands are used these materials are plasticized for 30 or 60 minutes at $1450^{\circ}C$, and are prevented from being cooled in the temperature range of $30{\sim}1000^{\circ}C$ when they are about to be cooled. XRD analysis and XRF analysis are used to determine the effects of this process on ${\gamma}-C_2S$ synthesization, the temperature at which a thing is plasticized, and the conditions for cooling that obtain in the plasticized clinker also, in order to confirm the $CO_2$ capture function, analysis of the major hydration products is conducted through an analysis of carbonatization depth and compressive strength, and through MIP analysis and XRD Rietveld analysis. As a result of these analyses, it is found that when ${\gamma}-C_2S$ was synthesized, the clinker that was plasticized at $1450^{\circ}C$ for one hour demonstrated the highest yield rate the sample with which the ${\gamma}-C_2S$ was mixed generated $CaCO_3$ when it reacted with $CO_2$ therefore, carbonatization depth and porosity were reduced, and the compressive strength was increased.

• Journal of the Korean earth science society
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• v.22 no.6
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• pp.558-570
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• 2001

The Middle Carboniferous Manhang and Geumcheon Formations exposed in the Taebaek area, Kangwondo, Korea consist of sandstones and shales with some intercalation of limestone beds. The limestones of the formations contain abundant conodonts and other fossils. The purpose of this study is (1) to investigate the conodont fauna, (2) to assign conodont biozones of the Manhang and Geumcheon Formations, and (3) to refine their geologic age more exactly. The conodonts of the Manhang and Geumcheon Formations are 6 genera distributed into 11 species. Conodonts found from limestones of the Manhang Formation are Idiognathodus delicatus, Hindeodus minutus, Streptognathodus sp., Diplognathodus coloradoensis, N. bothorops, and N. medexultimus. This conodont fauna can be assigned to the Neognathodus bothrops Zone. This conodont biozone indicates that the geologic age of the Manghang Formation is the Atokan stage of the Middle Carboniferous Period. Conodonts came from limestones of the Geumcheon Formation are Idiognathodus delicatus, N. medexultimus, N. roundyi, N. dilatus, Diplognathodus edentulus, Hindeodus minutus, Streptognathodus elegantulus, and Gondolella bella. These conodonts permit them to be assigned to the Neognathodus roundyi Zone. This Conodont biozone indicates that the geologic age of the Geumcheon Formation is the Desmoinesian stage of the Middle Carboniferous Period.