• YAKHAK HOEJI
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• v.29 no.4
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• pp.176-182
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• 1985

As a part of the studies on adsorptive properties of Korean halloysite clays, Hadong white clays of premium grade were examined for geometric pore structured by mercury porosimetry and for specific surface areas by nitrogen adsorption according to the BET procedure. Three size fractions of the native clay sample were derived from passage BS #100, #200 and #325 meshes, respectively. Several parameters lhus observed in relation to the pore structures are shown below: 1. The size fraction of BS #100, #200 and #325 show internal pore volumes of 25.3, 30.2 and $35.0m^2g^{-1}$, respectively. 2. In the distribution curves of the cumulative pore volume against pore diameter, it has been shown that the larticle sizes, the steeper the distribution over the larger ranges of pore diameters. The converse is true the smaller particles. 3. Internal pore areas increase with decrease in pore sizes. It follows that the pores having diameters of $\leq$0.1$\mu\textrm{m}$ are responsible for more than 90% of the total pore area. 4. The behaviour of nitrogen adsorption can be best described by BET type IV isotherm. Further, the hysteresis loops of the adsorptiondesorption curves become narrower with decresing particle sizes. 5. The specific surface areas observed for the fractions of BS #100, BS #200 and BS #325 are 34.6, 35.4 and 43.2m $^2g^{-1}$, respectively. and the calcined clay of BS #325 has a specific surface area near $30.4m^2g^{-1}$.

• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.3
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• pp.48-58
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• 1995

This study was conducted to investigate the plant community and to propose ecological planning methods for urban environmental forest on Gaepo neighborhood park, Gangnamgu in Seoul. Thirty-six plots that the size of each plot was 10$\times$10m(100\ulcorner) were set up and the vegetation analysis was carried out. Field survey was executed Apirl, 1994. The actual vegetation was consisted of Poplulus$\times$albaglandulosa community(73.03%), Robinia pseudoacacia community(8.30%) P. $\times$ albaglandulosa-R.pseudoacacia community(1.81%) and environmental forest (15.22%) in the survey site. According to mean importance values of each plot, survey area were divided into ten forest communities. As for the analysis of plant community structure which was classified into ten forest communities, the importance values, ecological diversity, number of species, number of individuals, basal area and crown coverage of urban environmental forest were relatively lower than those of the native community. In urban environmental forest of Gaepo neighborhood park, it showed problems for the planting method. So urban environmental forest should be constructed considering ecological characteristics based on above results.

• Clinics in Shoulder and Elbow
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• v.19 no.1
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• pp.51-58
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• 2016

The arthroscopic rotator cuff repair is now considered a mainstream technique with highly satisfactory clinical results. However, concerns remain regarding healing failures for large and massive tears and high revision rate. In recent decades, various repair strategies and construct configurations have been developed for rotator cuff repair with the understanding that many factors contribute to the structural integrity of the repaired construct. The focus of biomechanical test in arthroscopic repair has been on increasing fixation strength and restoration of the footprint contact characteristics to provide early rehabilitation and improve healing. These include repaired rotator cuff tendon-footprint motion, increased tendon-footprint contact area and pressure, and tissue quality of tendon and bone. Recent studies have shown that a transosseous tunnel technique provides improved contact area and pressure between rotator cuff tendon and insertion footprint, and the technique of using double rows of suture anchors to recreate the native footprint attachment has been recently described. The transosseous equivalent suture bridge technique has the highest contact pressure and fixation force. In this review, the biomechanical tests about repair techniques of rotator cuff tear will be reviewed and discussed.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.2
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• pp.83-93
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• 2003

This study was conducted for an understanding of a threatened plant species,“Penthorum chinense”, which is a vegetation structure and environmental characteristic in the southern part of Ibaraki, Japan. We selected distribution and contiguity area where P. chinense is not distributed and we set up 69 sites by the quardrat method. The surveyed general characters in each site include mean-height, mean-coverage, moisture condition water depth coverage and depth of litter layer. We calculated the degree of succession by the survey data and grasped the main distribution area, vegetation structure, growth environment of P. chinense by TWINSPAN classification and DCA ordination. The results of this study are as follows. First, P. chinense habitat was categorized into the riverside and abandoned paddy fields. The riverside was influenced by natural disturbance caused by flooding and drought. These conditions led to a poor P. chinense growth. The abandoned paddy fields as the artificial disturbance area have high potential value, because the area can preserve P. chinense growth space by succession control and water management. second, we executed TWINSPAN analysis based on vegetation coverage data of survey sites. The vegetation types were classified into the three categories: annual plant flora(P. chinense dominates in wet state), perennial plant flora(Solidago altissima dominates in dry state), and perennial plant flora(Phragmites communis dominates in wet state). Third, the data was ordinated by DCA. The sample sequences along the first and second DCA axes effectively reflected moisture condition, number of species, mean height, coverage of litter layer and degree of succession. Especially, P. chinense flora has the high correlation with moisture condition and number of species.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.2
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• pp.179-186
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• 1995

In the present study, nutritional status of some minerals in sheep grazed on native pasture was investigated in dry area, Ningxia district, of the People's Republic of China. Samples of some forages and blood of sheep were collected for two seasons, dry (March) and rainy (August) seasons. The Ca contents of forages (wheat straw, green-pea straw and some wild grasses) were relatively high as compared with that required ordinarily as standard, but on the contrary, the P content was much lower than that of standard. Consequently, Ca/P ratio was very high in cost of the roughages sampled in the region. Trace elements, Cu and Zn, content of forage samples were fairly low, and the contents of Mo and Fe were fairly high, particularly in some wild grasses, when the values were compared with that required normally. The Ca level in blood of sheep was in a range accepted as normal, and the other macro minerals(Mg and P) were contained at relatively high levels as compared with the values observed ordinarily, but not at a toxic level. With trace minerals, the plasma Fe level was extremely high as compared with the standard level, although there were no disorders due to toxicity, and Mo level in plasma was a little lower than the lower limit described as a normal. The plasma levels of other trace elements (Cu, Zn and Se) in all the animals were within the range accepted as normal. There would be no clear differences in mineral nutrition of sheep between dry and rainy seasons. These results could suggest that there is no severe unbalance and/or imbalance, and grazing sheep in the Ningxia area of midland China have no problems relating to the nutritional status of minerals.

• Journal of Environmental Science International
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• v.12 no.8
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• pp.853-860
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• 2003

Plants sequester atmospheric CO$_2$, a major agent of climate change, during the growing periods and mitigate its rising accumulation in the atmosphere. Pinus densiflora and Quercus mongolica are the native tree species dominant in the temperate forests of Korea. This study quantified the annual CO$_2$ uptake by the two species at forest sites in Chuncheon in the middle of the country. The quantification was based on seasonal measurements of CO$_2$ exchange rates under natural conditions by an infrared gas analyzer over the growing season (1999). The monthly CO$_2$ uptake per unit leaf area ranged from 1.6-6.7 mg/d㎡/h for P. densiflora and from 3.7-8.9 mg/d㎡/h for Q. mongolica, with a maximum in mid-summer. An equation for each species was generated to estimate easily the annual CO$_2$ uptake by total leaf area per tree, which subtracted the CO$_2$ release (i.e. respiration) by leaves and woody organs from the gross CO$_2$ uptake (diurnal uptake and release by leaves). Annual CO$_2$ release by leaves and woody organs accounted for 58-73％ of the gross CO$_2$ uptake across tree specimens. Annual CO$_2$ uptake per tree increased with increasing dbh (stem diameter at breast height) for the study diameter range, and was greater for Q. mongolica than for P. densiflora in the same dbh sizes. This was mainly associated with a greater total leaf area in the former. For example, the annual CO$_2$ uptake by one tree with dbh of 25 cm was 35.6 kg/yr for P. densiflora and 47.9 kg/yr for Q. mongolica. The results from this study can be applied to evaluate an atmospheric CO$_2$ reduction of woody plants by forest type and age class.

• Korean Journal of Animal Reproduction
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• v.23 no.1
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• pp.37-43
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• 1999

The image analyser was used for the measurement of the morphological changes of the spermatogenic cells and seminiferous tubules in the pheasant during the breeding and non breeding season. 1. The seminiferous tubules were enlarged 2.57 times during the breeding season than during the non breeding season. Only Sertoli cells and spermatogonia in the seminiferous tubules can be found during the non breeding season. 2. There is no significantly difference in the ratio of nucleus area against that of cell size in the spermatogonium between breeding and non breeding season. The ratio of area was 28.71% and 29.11%, respectively. However, the enlargement of spermatogonium was noticed during the non breeding season. 3. The highest value of the ratio of the nucleus area against that of cell size among the germ cells was measured 37.40% in the pachytene phase of the spermatocyte during the breeding season. 4. The ratio of nucleus area against that of cell size in the spermatid was 22.53%.

• Korean Journal of Veterinary Service
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• v.32 no.2
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• pp.171-176
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• 2009

Johne's disease is a chronic inflammatory bowel disease of cattle, sheep, goats and other ruminants, and Mycobacterium paratuberculosis is the etiologic agent of this disease. Many studies have been carried out on paratuberculosis from daily cattle and Korean native cattle in multiple areas around nation, but there is no report in Eastern-Gyeongbuk area. The purpose of this study is to investigate the seroprevalence of bovine paratuberculosis in Eastern-Gyeongbuk area. From July to December in 2007, blood samples were collected from 363 dairy cattle of 27 farms and 281 Korean cattle of 114 farms and the ELISA was conducted. 25 (6.9%) dairy cattle of 6 (22%) farms and 19 (6.8%) Korean cattle of 8 (7.0%) farms were positive in ELISA. In regional analysis, 25 (8.3%) out of 300 dairy cattle in Gyeungju were positive and Pohang were negative in this research. 12 (16.4%) out of 73 Korean cattle in Gyeungju and 7 (9.6%) out of 73 Korean cattle in Uljin were positive. Pohang and Youngdeok of Korean cattle were negative in this research. According to raising scale of dairy cattle, 4 (66.7%) farms out of 6 farms were raising 30 below and 2 (33.3%) farms out of were raising 30$\sim$70. And there were negative raising scale more than 70. In Korean cattle, 6 (75%) farms out of 8 were raising below 10 and 2 (25%) farms were raising 10$\sim$30. And there were negative raising scale more than 30. The rate of seropositive of paratuberculosis dairy cattle and Korean cattle were similar and the positive rate of Eastern-Gyeongbuk area is reported lower than that of any other region.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.6
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• pp.29-39
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• 2011

This study aimed to select evergreen broad-leaved trees (EBT) that can be produced and planted in Korea by analyzing the current use of the trees for landscaping in the Kyushu area of Japan, a warm temperate region. The results revealed the total production of EBT was higher than that of conifers and due to the suitable growth environment of the area and the subsequent high demand for them. The landscape tree production methods in Japan were divided into container nursery and outdoor nursery, and the uses and species of the trees varied depending on the method; a variety of native species were produced in container nursery rather than in outdoor nursery, whereas trees used as ornamental, gardening, and shade plants were produced in outdoor nursery rather than in container nursery. The results also showed that in Fukuoka, a major city in Kyushu that is adjacent to Korea, the planting rate of EBT, used as ornamental, gardening, and shade plants, was higher than that of deciduous broad-leaved trees and conifers. In the city, the planting rate of Cinnamomum camphora was the highest, Elaeocarpus sylvestris var. ellipticus, Ternstroemia gymnanthera, Ilex rotunda, Quercus glauca, Camellia sasanqua, Eurya emarginata, Pittosporum tobira, Raphiolepis indica var. umbellata, Hedera rhombea, Kadsura japonica, Trachelospermum asiaticum var. asiaticum. These species were verified in Kyushu area for their application as landscape trees and are expected to serve as landscape trees in Korea if the planting areas of them are expanded by global warming, urban heat island and regional microclimate.

• Journal of Animal Science and Technology
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• v.64 no.1
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• pp.143-154
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• 2022

This study was conducted to evaluate the relationship among market weight, slaughter age, yield grade, and primal cut yield in Hanwoo. A total of 403 Hanwoo (Korean native cattle) was assessed for carcass traits such as carcass cold weight, backfat thickness, ribeye area, dressing percentage, yield index, and marbling score. The production yield of the individual major primal cuts of Hanwoo beef was also measured. Carcass cold weight, ribeye area, and backfat thickness, which affect meat quality increased with increased market weight (p < 0.05). The production yield of the ten major primal cuts also increased with increased market weight (p < 0.05). In terms of slaughter age, carcass cold weight, ribeye area, and backfat thickness all increased from 25 months to 28-29 months, and the production yield of all prime cuts also increased with increasing slaughter age. According to the meat yield grade, carcass cold weight and backfat thickness increased from grade A to grade C, although the ribeye area was not affected. The combined findings of the study suggest that slaughtering Hanwoo at the weight of 651-700 kg and 701-750 and age of 28.23 and 29.83 months could be desirable to achieve the best quality and quantity grade of Hanwoo beef. However, the positive correlation of carcass cold weight and backfat thickness, and the negative correlation of the yield index according to primal cuts yield indicated that it is necessary to couple the slaughtering management of cattle with improved genetic and breeding method of Hanwoo to increase the production yield of the major prime cuts of Hanwoo beef.