• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.2
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• pp.93-100
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• 1995

This experiment was carried out to investigate how to effect the application of nitrogen, phosphate and potassium on the vegetation and dry matter yield in the mixed sward of orchardgrass and crabgrass (Digitaria sanguinalis [L.] Scop.). The experimental sward wa5 consisted of eight plots of non-application, P, K, PK, N. NK, NP and NPK. These plots were sown with seeds mixture of orchardgrass 17.5 kglha and crabgrass 17.5 kg/ ha on 22 April 1975 in the forage experimental field of Kangwon National University, Chunchon, Korea, and were cut four times from 6 July to 18 November 1975. The results obtained were summarized as follows: 1. In orchardgrass density measured after summering, the plot of nitrogen applied without phosphate marked only 3 1.0% of the plot of nitrogen applied with phosphate while in crabgrass density measured at that time the plot of nitrogen applied without phosphate marked as high as 112.5% of the plot of nitrogen applied with phosphate. 2. Application of phosphate and potassium improved wintering record of orchardgrass. In orchardgrass density measured after wintering, the plot of nitrogen applied without phosphate marked only 9.7% of the plot of nitrogen applied with phosphate, and the plot of NP applied without K marked 63.6% of the plot of NP applied with K. 3. In surface coverage of orchardgrass, in midsummer any plot applied with nitrogen regardless of accompanying with or not with phosphate wa5 0%, but in autumn the plot of nitrogen applied with phosphate was 56-58% and the plot of nitrogen applied without phosphate was 5%. While after wintering the plot of nitrogen applied with phosphate was 28-37% though the plot of nitrogen applied without phosphate was only 0.3-0.6%; the application of phosphate improved summering and wintering record of orchardgrass. 4. Application of phosphate demonstrated remarkable effect on increasing dry matter yield in orchardgrass. In year total yield of orchardgrass, the plot of nitrogen applied without phosphate marked as low as 11.3% of the plot of nitrogen applied with phosphate, but in crabgrass the plot of nitrogen applied without phosphate was almost equal to the plot of nitrogen applied with phosphate showing 97.5% of this plot. 5. Application of potassium was not effective on increasing dry matter yield of orchardgrass but its application was effective on increasing dry matter yield of crabgrass. In dry matter yield of orchardgrass significant difference was not found between NP plot and NPK plot, but in dry matter yield of crabgrass NPK plot recorded significantly higher yield compared with NP plot (p<0.05). 6. In botanical composition of the plot of nitrogen applied with phosphate, crabgrass recorded 46.5-50.5% in early summer (July) but in midsummer (August) it dominated the plot recording 85.6-91.2%. 7. In botanical composition based on the year total yield, in the plot of nitrogen applied with phosphate orchardgrass marked 21.7-26.2% and crabgrass recorded 73.8-78.370, but in the plot of nitrogen applied without phosphate orchardgrass marked only 3.5% being overwhelmingly dominated by crabgrass which recorded 96.5%. 8. Application of nitrogen not accompanied with phosphate strengthened competitive power of the crabgrass unilaterally, making orchardgrass be oppressed fatally by the crabgrass.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.366-378
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• 1998

Thermocondensation root canal filling technique have been used to fill accessary canals or to obtain homogeneous root caral fillings. But these thermocondensation technique inevitably produce heat in the canal which can be transmitted through the dentin and cementum and consequently damage periodontal ligamental cells and osteoblasts. In this study, System $B^{TM}$(Analytic technology, WA.D.S.A.) was used to evaluate the reaction of periodontal ligament tissue to "Continous Wave condensation technique" introduced by Buchanan, and the transmitted root surface temperature was measured according to measured root thicknesses. 12 Mandibular incisors of two adult dogs were used for the experiment. 6 controls were filled by lateral condensation technique with sealer.3 specimens were apically filled by Continuous Wave technique at $200^{\circ}C$ for 5 seconds and remaining 3 specimens were additionally backfilled using System $B^{TM}$(Analytic technology, WA.D.S.A.) was used to evaluate the reaction of periodontal ligament tissue to "Continous Wave condensation technique" introduced by Buchanan, and the transmitted root surface temperature was measured according to measured root thicknesses. 12 Mandibular incisors of two adult dogs were used for the experiment. 6 controls were filled by lateral condensation technique with sealer.3 specimens were apically filled by Continuous Wave technique at $200^{\circ}C$ for 5 seconds and remaining 3 specimens were additionally backfilled using System $B^{TM}$ at $100^{\circ}C$ for 20 seconds. Six weeks later, the dogs were sacrificed and the teeth stained with Hematoxylin and Eosin for histologic examination. 6 extracted human teeth were used to measure the transmitted temperature. After cutting off the crown, the canals were prepared and divided into 3 groups with root thickness of 1.5mm, 1.0mm, 0.5mm, 2 teeth in each group. Inside each root canal, System $B^{TM}$ was heated as with the temperature for the apically condensed and the back filled group, and the transmitted heat was measured on the external surface of the root. The temperature of System $B^{TM}$ heat spreader at $200^{\circ}C$ and $100^{\circ}C$ was also measured at root temperature. It can be concluded as follows: 1. In the thin area (200-$250{\mu}m$) of the root, root resorption could be seen even with heating at $200^{\circ}C$ for 5 seconds. 2. When the spreader was heated at $200^{\circ}C$ for 5 seconds and additionally at $100^{\circ}C$ for 20 seconds for backfill, all teeth showed root resorption regardless of their root thickness. 3. The transmitted external root surface temperature was higher as the root thickness decreased and as the heating time increased. In the thermocompaction technique using System $B^{TM}$, the spreader should be heated for the minimal time and used only in the apical area. The heated spreader shouldn't inserted to the binding point of the canal and backfilling should be done with other means of minimally heated gutta percha technique.

• Animal Bioscience
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• v.34 no.1
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• pp.48-55
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• 2021

Objective: This study was conducted to investigate the effects of wilting and microbial inoculant treatment on the fermentation pattern and quality of Italian ryegrass silage. Methods: Italian ryegrass was harvested at heading stage and ensiled into vinyl bags (20 cm×30 cm) for 60d. Italian ryegrass was ensiled with 4 treatments (NWNA, no-wilting noadditive; NWA, no-wilting with additive; WNA, wilting no-additive; WA, wilting with additive) in 3 replications, wilting time was 5 hours and additives were treated with 106 cfu/g of Lactobacillus plantarum. The silages samples were collected at 1, 2, 3, 5, 10, 20, 30, 45, and 60 days after ensiling and analyzed for the ensiling quality and characteristics of fermentation patterns. Results: Wilting treatment resulted in lower crude protein and in vitro dry matter digestibility and there were no significant differences in acid detergent fiber (ADF), total digestible nutrient (TDN), water-soluble carbohydrate (WSC), ammonia content, and pH (p>0.05). However, wilting treatment resulted in higher ADF and neutral detergent fiber content of Italian ryegrass silage (p<0.05), and the WNA treatment showed the lowest TDN and in vitro dry matter digestibility. The pH of the silage was higher in the wilting group (WNA and WA) and lower in the additive treatment group. Meanwhile, the decrease in pH occurred sharply between the 3-5th day of storage. The ammonia nitrogen content was significantly lower in the additive treatment (p<0.05), and wilting had no effect. As fermentation progressed, the lactic and acetic acid contents were increased and showed the highest content at 30 days of storage. Conclusion: The wilting treatment did not significantly improve the silage fermentation, but the inoculant treatment improved the fermentation patterns and quality of the silage. So, inoculation before ensiling is recommended when preparing high quality of Italian ryegrass silage, and when wilting, it is recommended to combine inoculation for making high quality silage.

• Journal of the speleological society of Korea
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• no.4
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• pp.41-50
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• 1996

The coastal plains of the Puna and Ka' u Districts of the island of Hawaii are a contradiction to the popular view that the island of Hawaii is a tropical rain forest or a vegetated landscape with abundant water sour This section of the island lies in the rain shadow of Mauna Loa a Kilauea Volcanoes and receives less than 30 inches of annual precipita When rain does come. it is in the form of sudden down pours. givi residents of the area little time to collect and conserve water. Due to porous nature of the rock. there is no standing surface water. In spite of these harsh climatic conditions. archeological evidence indic that an extensive agriculture complex existed not only along the coast. into the most remote parts of what is called the Ka'u Desert. Pass through these agricultural areas are historic and pre - historic t systems. These trail systems apparently played a significant suppor role for exchange between the ahupua's (classic land divisions of Haw and the geopolitical districts. The question arises as to how could vast agricultural complexes a heavy foot travel over miles of arid land exist without dependable wa sources\ulcorner While planting - pits and mounds were designed to make most efficient use of available water and conserve moisture(Carter 19 9). people involved in planting also needed potable water for surv Most publications and research papers dealing with the early population this area make only oblique reference to springs and wells which t populations depended upon. The Federal Cave Resource Protection Act(1988) has served as imprtus for the National Park Service to look closer at the lava tu caves and fault cracks within Hawaii Volcanoes National Park. P visitors to these underground areas found large volumes of standing wa in fault cracks. and abundant drip areas with the lava tubes. Re observes noted that in most cases. where the cracks and caves we located in the arid sections of the park. there has been extens modifiacation or utilization of these water sources by the early Hawaii and others. The variety of western containers used for collection indica that these water sources were used during historic times. William E described similar water sources in his narrative of his trip around island in 1823(Eills 1979), This report is directed at documenting recent observations and a stimulating further research into early Hawaiian water collection syst It also explores the implications that power and political influence of e chiefs in the arid portions of Hawaii could have been linked to the con of the water resources.

• Analytical Science and Technology
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• v.20 no.6
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• pp.516-523
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• 2007

Purification of silica mineral has been investigated by acid leaching of pulverized silica. A series of studies has been carried out on the effect of leaching silica powder as a function of the leaching time at the constant temperature of $80^{\circ}C$ in oxalic acid, aqua regia, and two mixed acids of HF/HCl, $HF/HNO_3$. The impurities of silica and leachantes were measured by neutron activation analysis (NAA), inductively coupled plasma atomic emission spectrometry (ICP-AES), atomic absorption spectrometry, x-ray fluorescence (XRF) method and wet analysis (WA). Certain metals, such as sodium, calcium, iron, aluminium and titanium, have been found in concentrations of hundreds or even thousands of mg/kg. Comparison of purification processes of silica and analytical methods of impurities in the silica was conducted in this study.

• Journal of the Korean housing association
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• v.17 no.4
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• pp.93-100
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• 2006

The purpose of the study was to analyze the appropriateness of space in multi-family housing by examining the current conditions of space, space norms and deficits, satisfaction with and needs for the spaces of individual rooms. The data came from the survey with 412 households living in Haeundae New Town, Busan and were analyzed with descriptive statistics. The appropriateness of space were mainly investigated in terms of housing size, number of bedrooms, and number of bathrooms. In terms of current space conditions, the highest portion of the households live in apartments with $20\sim30s$ pyong, 3 bedrooms, and 2 bathrooms. It was found that the space norms included housing with $30\sim40s$ pyong, 3 bedrooms, and 2 bathrooms. Households in current study tended to have some space deficits, especially in housing size and number or bathrooms. In general, the satisfaction with the current space of individual rooms were generally low except living room and master bedroom. It was also found that the households were more likely to make the second biggest bedroom bigger than now. The stages of family life cycle has significant effects on needs for the spaces of several rooms, such as dining room, room2, and room3.

• 보존과학연구
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• s.22
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• pp.27-40
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• 2001

DNA typing is often used to determine identity from human remains. Recently, the molecular biological analysis of ancient deposits has become possible since methods for the recovery of DNA conserved in bones or teeth from archaeological remains have been developed. In the field of archaeology, one of the most promising approaches is to identify the individuals present in a mass burial site. We performed nuclear DNA typing and mitochondrial DNA sequencing analysis based on PCR from a Korea ancient human remain excavated from Sa-chon Nuk-island and civilian access controlline(CACL). A femur bone were collected and successfully subjected to DNA extraction, quantification, PCR amplification, and subsequently typed for several shot tandem repeat(STR)loci. 4 types of STR systems used in this study were CTT multiplex(CSF1PO, TPOX, TH01), FFv multiplex(F13A01, FESFPS, vWA), Silver STRⅢ multiplex(D16S539, D7S820, D13S317), and amelogenin for sex determination. This studies are primarily concerned with the extraction, amplification, and DNA typing of ancient human bone DNA samples. Also, it is suggestive of importance about closely relationship between both fields of archaeology and molecular biology.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.8
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• pp.809-815
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• 2009

The previous work(Cheong et al., 2006) where the characteristics of acoustic emissions of wind turbines has been investigated according to the methods of power regulation, has showed that the acoustic power of wind turbine using the stall control for power regulation is more correlated with the wind speed than that using the pitch control. In this paper, basically extending this work, the noise generation characteristics of large modern upwind wind turbines are experimentally indentified according to the power regulation methods. To investigate the noise generation mechanisms, the distribution of noise sources in the rotor plane is measured by using the beam-forming measurement system(B&K 7768, 7752, WA0890) consisting of 48 microphones. The array results for the 660 kW wind turbine show that all noise is produced during the downward movement of the blades. This result show good agreement with the theoretical result using the empirical formula with the parameters: the convective amplification; trailing edge noise directivity; flow-speed dependence. This agreement implies that the trailing edge noise is dominant over the whole frequency range of the noise from the 660 kW wind turbine using the pitch control for power regulation.

• The korean journal of orthodontics
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• v.18 no.2
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• pp.367-385
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• 1988

In case of skeletal Class III malocclusion with underdeveloped maxilla, the extraoral orthopedic force for the stimulation of maxillary growth or anterior reposition of the maxilla has been used clinically for the improvement of facial skeletal relationship. The purpose of this investigation was to examine the initial reaction of maxillofacial complex to the maxillary protraction by using extraoral orthopedic force. The dried human skull was used and this investigation was done by means of double exposure holographic interferometry. The protraction forces placed on the canine or the first molar were parallel, $10^{\circ}$ downward, $20^{\circ}$ downward to the occlusal plane. Fringe pattern of each protraction condition was compared and analized. The results were as follows: 1. Each maxillofacial bone displaced saparately. 2. More displacement was shown at the area of the teeth and the alveolar bone. 3. A counterclockwise rotation of the maxilla wa decreased by downward protraction and especially 20 degree downward protraction from the canine showed least rotation. 4. On the zygomatic arch, outward bend was observed and this effect was decreased by downward protraction. 5. On the zygomatic bone, the counter clockwise rotation was increased by the downward protraction. 6. When maxillary expansion was applied at the same time, outward and upward displacement with counterclockwise rotation was observed on the maxilla. 7. The lateral pterygoid plate of sphenoid bone was affected by maxillary protraction.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.6
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• pp.19-28
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• 2004

Segmental Retaining Wall(SRW) has been variously applying in Civil and Architecture construction. Recently, the application of environmental element in all type's structures came to essential requirement, and the construction cases of retaining wall using reinforced soil and block are more increased than the past. But, this trend more widely was spread environmental element as landscape work for the backside of reinforced retaining wall as well as block itself. New environmental block, Greenstone Block, developed to apply of this tendency. The retaining wall system using Greenstone can be environmental constructing at both block itself and backside of retaining wall. The material tests, the axial compressive strength test of block and bending test of fiber-pipe, exercised to design and construction of vertical SRW, which were satisfied NCMA standard. Through this procedure, Rewall (ver 1.0) was developed, which can be automation design of SRW including internal stability, external stability and local stability. And these can be considered setback of retaining wall, as well the examples of vertical retaining wall using block presented to satisfying the follows; strength of reinforced geotextile, height of retaining wall, surcharge, types of backfill and groundwater level etc. Many problems investigated on after or before of construction were due to local failure, insufficiency of bearing capacity and groundwater level. Especially, the local failure was many occurred to during compaction or after construction, and the cases of SRW construction is similar to the results of model test on vertical SRW.