• Journal of the Korean GEO-environmental Society
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• v.15 no.1
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• pp.63-68
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• 2014

In this study, it was found that determined the photocatalytic degradation of antibiotics (lincomycin, LM) with various catalyst composite of titanium dioxide ($TiO_2$), hydroxyapatite (HAP) and germanium (Ge) under UV-A irradiation. At first, various type of complex catalysts were investigated to compare the enhanced photocatalytic potential. It was observed that in order to obtain the removal efficiencies were $TiO_2/HAP/Ge$ > $TiO_2/Ge$ > $TiO_2/HAP$. The composition of $TiO_2/HAP/Ge$ using a statistical approach based on mixture analysis design, one of response surface method was investigated. The independent variables of $TiO_2$ ($X_1$), HAP ($X_2$) and Ge ($X_3$) which consisted of 6 condition in each variables was set up to determine the effects on LM ($Y_1$) and TOC ($Y_2$) degradation. Regression analysis on analysis of variance (ANOVA) showed significant p-value (p < 0.05) and high coefficients for determination value ($R^2$ of $Y_1=99.28%$ and $R^2$ of $Y_2=98.91%$). Contour plot and response curve showed that the effects of $TiO_2/HAP/Ge$ composition for LM degradation under UV-A irradiation. And the estimated optimal composition for TOC removal ($Y_2$) were $X_1=0.6913$, $X_2=0.2313$ and $X_3=0.0756$ by coded value. By comparison with actual applications, the experimental results were found to be in good agreement with the model's predictions, with mean results for LM and TOC removal of 99.2% and 49.3%, respectively.

• The Journal of Engineering Geology
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• v.28 no.1
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• pp.101-115
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• 2018

This study was carried out to evaluate the effects of various filter conditions on unconfined aquifer (alluvial aquifer). We made model test device which has filter layer, pumping well and observation well which consist of sand layer and gravel layer to test. Step drawdown test and long term pumping tests were carried out using the device. The permeability characteristics of each test group were confirmed and the optimal yield was calculated. As a result of comparing the optimal yield of double filter and single filter in sand, dual-filter SD-300 was valued at 216.8 % higher final optimal yield than single-filter SS-300. Comparing the dual filter SD-300 and the single filter SS-100 with a thin filter layer, dual-filter SD-300 was valued at 709.2% higher final optimal yield than single-filter SS-300. As a result of analysis of optimal yield change over time, It was confirmed that the ratio of optimal yield of single filter and dual filter increase over time. In order to evaluate the long-term change in water intake efficiency, we considered the point at which the initial optimal yield was reduced by 50%. The dual filter SD-300 is about 351.1% higher than SS-300, which is the same thickness filter, and about 579.0% higher than SS-100. From these results, Assuming that the point at which the initial quantity of water intake is reduced to 50% is the well life, double filters are expected to increase their lifespan by about 3.5 times over single filters of the same thickness and by about 5.8 times over typical single filter. These results can be used to design wells to river bank filtration or filtered seawater. In addition, it is possible to clarify the effect of the double filter through the comparison with the future field test results.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.4
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• pp.341-350
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• 2008

This trial was conducted to investigate effects of different feeding types of conventional or total mixed rations (TMR) provision on feed intake, nutrient digestibility, nitrogen retention and blood metabolite characteristics in different breeds of native and cross bred Korean black goats. Ten Korean native male goats and 10 Korean crossbred black male goats (Korean native $\times$ Australian feral crossbred, 50:50), average 18 kg of BW, were used in this trial, and each breed of Korean black goats was separated into conventional and TMR diets treatments in a randomized complete block design. Conventional diet was based on forages and commercial diet. All animals were housed in individual metabolism crates and were fed ad libitum. Water was available at all times. Experimental period totally lasted for 38 days, consisting of 14 days of adaptation, 10 days of preliminary period and 14 days of sample collection period. Daily dry matter intake was significantly (p<0.05) higher in TMR treatments of the crossbred goats. Within breeds, crossbred rather than native-bred consumed more highly, and within the feeding type, TMR diets were more fed in comparison with conventional diet. Average daily gain ranked the highest in crossbred : TMR, followed by crossbred: conventional diet, native-bred: TMR, and native-bred: conventional diet (p<0.05). Dry matter digestibility was significantly (p<0.05) higher for TMR than for conventional diets, and it was higher in crossbred than in native-bred Korea black goats. Nitrogen retention was highest in TMR treatments of crossbreed, whereas it was lowest in conventional diet of native breed (p<0.05). Plasma glucose and urea nitrogen concentrations were significantly (p<0.05) higher in crossbred than in native-bred Korean black goats. Overall, the results indicated that feeding total mixed ration to crossbred rather than native-bred Korean black goats had more favourable influences on their performances, intakes, digestibility, nitrogen retention and blood metabolite characteristics. In conclusion, it is conceived that the results may contribute to economical benefit to farms producing Korean black goats together with establishment of an efficient feeding management system.

• Horticultural Science & Technology
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• v.31 no.3
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• pp.259-268
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• 2013

This study was carried out to evaluate the visual turfgrass's color quality, winter color, and spring green-up under three different soil systems and to make a practical use for sports turf design and construction. Several turfgrasses were evaluated in multi-layer, USGA and mono-layer systems. Turfgrass entries in the study comprised of 3 cultivars from Korean lawngrass (Zoysia japonica Steud.) of typical warm-season grass (WSG) and 3 blends and 3 mixtures from Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), and tall fescue (TF, Festuca arundinacea Schreb.) of cool-season grass (CSG). Significant differences were observed in the turfgrass's color quality, winter color, and spring green-up in the study. Seasonal variation of visual turf color greatly occurred according to soil systems and turfgrasses. Multi-layer and USGA systems were highly associated with better visual color ratings, as compared with mono-layer system. Regardless of soil system, visual turf color in all entries was better from spring to fall than in winter. Great color differences were observed during a period of early December to early spring. CSG produced a better color quality over WSG in any soil system. Overall color ratings for CSG were KB > PR > Mixtures > TF. As for a winter color, its ranking was USGA > multi-layer > mono-layer system. No difference was found in winter among cultivars of Korean lawngrass, being completely brown, but great differences among CSG. Rated best for winter color was PR, followed by CSG mixtures, KB and finally TF in order. It was generally conceded that fast green-up in spring was greatly related with multi-layer over mono-layer system and also CSG over WSG. Among CSG, TF had a fastest green-up. PR was also fast in green-up, but poor in color uniformity. KB, however, was the slowest due to shallow rooting system, when compared with other CSGs. These results demonstrate color differences were greatly variable according to soil systems and also among turfgrass species. A precise decision should be made in selecting turfgrass species and soil system. Multi-layer and USGA systems were considered as the suitable one for turfgrass color quality, winter color and spring green-up. It is a great necessity to combine proper soil system, right turfgrass species, and appropriate mixing rates by a concept-oriented approach, when establishing garden, parks, soccer field, and golf courses and so on.

• Journal of the Korean Wood Science and Technology
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• v.17 no.2
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• pp.34-64
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• 1989

Corner block with anchor bolt(CBA) joint method used in knock-down type table furniture manufacturing can reduce the packing and transporting cost. Unfortunately. it also has the disastrous defect to be loosend and unstable during the service life mainly due to fatigue and creep(repeated and prolonged loading). So 22 joint groups constructed were tested to evaluate the effect of some design factors related to the size of side rail(apron). block attachment to side rail. and the number of anchor bolt as well as the effect of the type of corner block(mitered type vs. rectangular type) Usable strength from the stiffness coefficients of each joint group were analysed with SPSS /PC+ and described as the criteria of CBA joint construction. The conclusions were as follows: The height of side rail(50, 75 and 100 mm) and the addition of polyvinyl acetate(PVAc) emulsion in the corner block attactment to side rail had the effect on raising the usable strength of CBA joint with remarkable high significance. And the effect of 2 - anchor bolts was also superior to that of 1 - bolt significantly. However. the thickness of side rail(22 mm vs. 25 mm) had no effect on the strengthening the table joint rigidity. Mitered type corner block joint appeared to he recommendable for CBA jointed table construction rather than the rectangular type one regardless of the method of block attachment to side rail. The best result identified from Duncan's multiple comparison was in the construction with 25 mm thick and 100 mm height of side rail fastened using 2 - anchor bolts in mitered type corner block. But it would be reasonable to use 22 mm thick & 75 mm high side rail and mitered corner block with PVAc emulsion & 2 bolts considering the productivity and production cost down in the MDF furniture manufacturing industries.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.3
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• pp.85-95
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• 2008

The City of Seoul enforces the 'Median reserved bus lane', a revised public transportation system, in order to achieve both a faster and more convenient transit system. This study examines the visual image and preference of the median bus stops in accordance with the operation of the median reserved bus lanes. In order to evaluate and clarify the distinct landscape of each bus stop in a different environment, our team selected 3 representative bus stops with different environments on main roads and conducted landscape simulations so as to evaluate visual preference. The sites were on a narrow range road, wide width road in the downtown area and wide width road on the outskirts of the city. The preference degree for each selected bus-stop environment was compared. The comparison conditions were a median bus stop with preexisting landscape, a median bus stop with planted trees, and a landscape without a median bus stop. The results of the study can be Summarized as follows: First, the visual influence on median bus stops depends on the visual complexity of the environment where they are located. People had an affinity for the median bus stop in which the visual complexity was low, while the preference degree of median bus stop was low in a highly complex area. Secondly, regardless of regional environment where median bus stops are located, research showed that it is more "impressive" to have a median bus-stop with planted trees than landscape without a median bus stop. Thirdly, the median bus stop with plants highly preferred over one without moreover, the landscape with planted trees would provide a comfortable mind for people. This study reveals that planting-oriented design concepts in median bus stops exhibit significant differences in the preference assessment factors. Thus, for further median bus stop construction, planting is desirable to create an impressive streetscape and better scenic quality.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.2
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• pp.34-44
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• 2020

The purpose of this study was to investigate the difference in perceptions between gardens and park functions as recognized by two groups, Group A and Group B, in order to confirm the distinction between concepts and functions and then establish the importance of individual functions. The AHP was used to analyze the importance of each group's perceptions by dividing them into garden and park, Group A and non-Group A, respectively. In Group A, the importance of garden functions were considered in descending order of importance to be cultural function, ecological function, and social function. In the general group, ecological function, cultural function, and social function also appeared, but in a different order of importance. As for the park functions, Group A recognized the importance of functions in a similar order of importance to the gardens: cultural function, ecological function, and social function. Group B thought that social function, ecological function, and cultural function have the same significance. At the major classification level, Group A and Group B emphasized the social function of the parks. Group A recognized the importance of the garden's cultural function as the most important, whereas the general group emphasized the importance of the garden's ecological function. As for the mid-class level, Group A recognized the aesthetic beauty, health, ecological environment protection, and water circulation as important functions of the garden. For Group B, the ecological environment protection, aesthetic beauty, water cycle, and health were important. The concepts and functions of gardens and parks are still largely mixed but are gradually becoming differentiated. As a follow-up study, it is important to systematically manage the functions of gardens by establishing design, construction, and monitoring DB techniques for the garden type and examine the hierarchy of various other gardens.

• Korean Journal of Poultry Science
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• v.44 no.4
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• pp.253-258
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• 2017

This study was aimed at evaluating the additivity of crude protein digestibility in mixed diets of corn and soybean meal (SBM), and comparing direct and indirect methods for evaluating crude protein (CP) digestibility. Totally, five hundred and twenty-five 18-day-old broiler chickens were grouped into 7 blocks based on body weight, and randomly allocated to 6 treatment groups in a randomized complete block design. The basal diet, diet 3, was corn-SBM-based, containing 65% corn and 28% SBM. Diets 1 and 5 contained corn and SBM, respectively, as the sole CP source. To use the difference method, 2 diets, diets 2 and 4, were prepared by mixing corn and SBM at the expense of the basal diet, respectively. Diet 2 contained 79% corn and 14% SBM, and diet 4 contained 32.5% corn and 34% SBM. To evaluate the additivity of digestibility values, the difference between measured values for the mixed diets (diets 2, 3, and 4) and predicted values calculated using the measured values for diets 1 and 5 was examined. The apparent (AID) and standardized (SID) ileal digestibility of CP in SBM differed between the direct and indirect methods; however, corresponding digestibility did not differ for corn. Additionally, the predicted and measured digestibility of both AID and SID differed in diets 2 and 3, implying that the digestibility values obtained from diets 1 and 5 were not additive for mixed diets. In conclusion, this study showed that digestibility evaluated by direct and indirect methods depends on the ingredients having different CP concentrations, and this finding may be considered to improve the accuracy of feed formulation for broiler chickens.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.567-573
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• 2010

Research was initiated to investigate early establishment characteristics and germination pattern of fine-textured fescues (FF). Six varieties from Chewings fescue ($Festuca$ $rubra$ L. ssp. $commutata$ Gaud., CF), creeping red fescue ($F.$ $rubra$ L. ssp. $rubra$ Gaud., CRF), hard fescue ($F.$ $ovina$ ssp. $longifolia$ Thuill., HF) and sheep fescue ($F.$ $ovina$ L., SF) were evaluated in the study. An alternative environmental condition requiring a FF germination test by International Seed Testing Association (ISTA) was applied in the experiment, consisting of 8-hr light at $25^{\circ}C$ and 16-hr dark at $15^{\circ}C$ (ISTA conditions). Daily and cumulative germination patterns were measured and analyzed on a daily basis. Significant differences were observed in germination pattern, days to the first germination, days to 50% germination, days to 60% germination, and germination rate. The final germination percentage was variable with species and varieties, being 40.25 to 82.00% at the end of study. There were considerable variations in early germination characteristics and germination pattern among FF species. The first germination in all entries except HF was initiated between 5 and 6 DAS (days after seeding) under ISTA conditions, while HF between 6 and 7 DAS, being 1 day later. It was 8 to 10 DAS in days to the 50% germination, which was 2 to 4 days after the first germination date. Days to the 60% germination were 9.10 to 14.80 DAS under ISTA conditions, being 5.70 days in differences among the entries. CF 'Jamestown II' and 'Shadow II' and HF 'Aurora Gold' were the fast varieties. The slowest one was HF 'Rescue 911'. Among FF species, turf establishment speed was becoming faster in CRF, SF, HF and CF in this order. Information on differences in germination characteristics and pattern from this study would be usefully applied for golf course design and construction, when established with FF.

• Korean Journal of Psychosomatic Medicine
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• v.9 no.1
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• pp.28-36
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• 2001

Objectives : This study was undertaken to identify the clinical and psychological characteristics in patients of mental disability assessment following traumatic brain injury who had the finding with or without abnormal brain imaging study. Methods : A consecutive series of 59 patients were assessed in hospital from January 1994 to December 1998. Patients were divided into 2 groups based on normal or abnormal brain imaging and the two groups were compared in demographic characteristics, psychiatric symptoms, type of head injury, clinical psychological findings. There were 27 patients with abnormal findings and 32 with normal findings in brain imaging study. Results : Abnormal finding group in brain imaging study had significantly higher incidence of psychosis, decreased memory, decreased appetite, increased nihilistic idea, and intracranial hemorrhage. Also, abnormal finding group showed significantly lower level of performance on the block design subtest of K-WAIS and had significantly lower scores on F, hypochodriasis, depression, hysteria, psychopathic deviate, psychasthenia and schizophrenia subscale of the MMPI. Conclusion : The findings suggest that the patients undergone brain surgery due to intracranial hemorrage at that time of brain injury may have higher frequency of abnormal findings in brain imaging study, complain more cognitive and affective symptoms, and have lower the abstract concept formation and perceptual organization abilities.