• Journal of The Korean Society of Grassland and Forage Science
• /
• v.35 no.2
• /
• pp.137-144
• /
• 2015

This study was carried out to investigate the growth characteristics, yield, and chemical compositions of corn hybrids for silage according to the drainage depths in a lowland paddy field. The experimental design was arranged in a randomized block design with four treatments and three replications. The drainage depths of the four treatments were 0 cm, 20 cm, 30 cm and 50 cm. Tip-filling degree, ear length, and ear circle were higher in the 30 cm and 50 cm treatments compared with the other treatments (p < 0.05); but the plant length, leaf length, leaf width, ear height, stem diameter, and stem hardness were not significantly different (p < 0.05). The brix was higher in the order of 20 cm > 0 cm > 50 cm > 30 cm treatment. The fresh yield, dry matter yield, and TDN yield increased as the drainage depth increased (p < 0.05). The crude-protein and crude-ash content were highest in the 50 cm treatment (p < 0.05), but the crude-fat, NDF, ADF, and crude-fiber levels were not significantly different (p < 0.05). The total mineral content was higher in the order of 0 cm > 30 cm > 20 cm > 50 cm treatment (p < 0.05). Fructose, glucose, and sucrose were highest in the 20 cm treatment. The total amino-acid (EAA + NEAA) content was the highest in the 50 cm treatment. Based on these results, greater drainage depths increased the yield and feed value of silage corn.

• Journal of Korean Society for Atmospheric Environment
• /
• v.7 no.1
• /
• pp.55-65
• /
• 1991

The study was performed to select a adaptable tree species under stressed field conditions where there are a industrial plants operating with a number of smoke stacks emitting pollutants, such as hydrogen fluoride and sulfur dioxide. As a result of the study, a tree species selected are due to construct a forest belt in a zones near industrial plants to reduce the concentrations of air pollutants. The concentrations of atmospheric hydrogen fluoride and sulfur dioxide were very higher at experimental sites near industrial plants (air-pollution sites) than at control site. The leaves of 7 tree species grown at air pollution sites contained more sulfur and, specially, fluorine than at those control site. Among the tested tree species, Ligustrum japonicum Thunb. and Euonymus japonica Thunb. grown at air pollution sites did not at all break out a foliar injury but appeared to be healthy, as well as those grown at control site. Acer pseudo-sieboldianum Kom., Pinus virginiana Mill., Larix leptolepis Gordon., Pinus koraiensis Sieb. et Zucc., Pinus strobus L., Picea abies Karst and Ligustrum obtusifolium Sieb. et Zucc., however, showed a severe fluoride-type foliar injury such as necrosis on tip or margin of leaves, etc. Fluorine found in leaves was proved to be correlated to sulfur found in leaves whereas index of foliar injury hadn't a good correlation to pollutants found in leaves. It appears that Euonymus japonica Thunb., Ligustrum japonica Thunb., Platanus acerifolia Willd, Chamaecyparis pisifera Endl., Populus tomentiglandulosa T. Lee and Sophora japonica L. grown at both experimental sites had a high value of percent survival whereas Pinus virginiana Mill., Pinus koraiensis Sib. et Zucc., Koelreuteria paniculata Laxm. and Alnus hirsuta Rupr. had an extremely low value of that. In comparison with control site, the percent tree height increments in Chamaecyparis pisifera Endl., Ligustrum japonicum Thunb., Quercus acutissima Carruth., Populus tomentiglandulosa T. Lee, Pinus thunbergii Parl and Euonymus japonica Thunb. and the percent upmost root diameters in Populus tomentiglandulosa T. Lee, Chamaecyparis pisifera Endl., Euonymus japonica Thunb., Ligustrum japonicum Thunb., Betula platyphylla var. japonica Hara and Pinus thunbergii Parl. cultivated at air polluted sites showed very high value above 90%, respectively. A significant negative correlation (r=-0.662) was recognized between the index of foliage injury and the percent collective character, which was the mean of tree characters such as percent survival, percent tree height increment and percent upmost root diameter increment which compared to those at air polluted site with those at control site. Based on the percent collective character Ligustrum japonicum Thunb., Euonymus japonica Thunb., Chamaecyparis pisifera Endl., Populus tomentiglandlosa T. Lee, Betula platyphyla var. japonica Hara and Platanus occidentalis L. have large value about 90%, respectively. Therefore, the results indicate that this tree species are adaptable species in air polluted regions. For better understanding of the adaptable tree species, furthur studies concerning the effects of various air pollutants on the tree growth are required.

• The Korean Journal of Pain
• /
• v.1 no.2
• /
• pp.203-206
• /
• 1988

Evaluation of inadvertent dural puncture occuring among 308 epidural blocks done for the relief of pain from various conditions was performed. Dural puncture was suspected in 5 out of 308 epidural bloks. (1.6%) Aspiration of CSF was negative in 3 cases in which dural puncture was suspected only after developing spinal anesthesia. Of the 3 negative CSF aspirations, one case had a history of laminectomy. Adhesions of the adjacent tissues might result in the loss of flexibility and a decrease in potential epidural space which might cause dural tearing during injection and subarachoid injection of the local anesthetic followed by high spinal anesthesia. In another case, the needle tip was obstructed by tissue which led to negative aspiration of CSF and failure to feel loss of resistance. The second injection at the same site may cause subarachnoid injection of the local anesthetic through the previously perforated dura mater and in turn, lead to spinal anesthesia. In the last case, there was no reason to suspect dural puncture since the loss of resistance plus air rebound were definite and aspiration of CSF was negative, but dural puncture was suspected after the patient developed spinal anesthesia.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.19 no.3
• /
• pp.389-407
• /
• 2017

In the current work, a series of three-dimensional finite element analysis was carried out to understand the behaviour of pile when the tunnel passes through the lower part of a single pile or group piles. At the current study, the numerical analysis analysed the results regarding the ground reinforcement condition between the tunnel and pile foundation. In the numerical modelling, several key issues, such as the pile settlements, the axial pile forces, the shear stresses and the total displacements near the tunnel have been thoroughly analysed. The pile head settlements of the single pile with the maximum level of reinforcement decreased by about 16% compared to the pile without ground reinforcement. Furthermore, the maximum axial force of the single pile with the maximum level of ground reinforcement experienced a 30% reduction compared to the pile without reinforcement. It has been found that the angle of ground reinforcement in the transverse direction affects the pile behaviour more so than the length of the ground reinforcement in the longitudinal direction. On the other hand, in the case of the pile group with the reinforced pile cap, the ground displacement near the pile tip appears to be similar to the corresponding ground displacement without reinforcement. However, it was found that the pile cap near the pile head greatly restrained the pile head movement and hence the axial pile force increased by about 2.5 times near the pile top compared to the piles in other analysis conditions. The behaviour of the single pile and group piles, depending on the amount of ground reinforcement, has been extensively examined and analysed by considering the key features in great details.

• Journal of the Microelectronics and Packaging Society
• /
• v.11 no.2 s.31
• /
• pp.59-66
• /
• 2004

This paper presents a novel fabrication process for a tapered hollow metallic microneedle array using backside exposure of SU-8, and analytic solutions of critical buckling of a tapered hollow microneedle. An SU-8 meta was formed on a Pyrex glass substrate and another SU-8 layer, which was spun on top of the SU-8 mesa, was exposed through the backside of the glass substrate. An array of SU-8 tapered pillar structures. with angles in the range of $3.1^{\circ}{\sim}5^{\circ}$ was formed on top of the SU-8 mesa. Conformal electrodeposition of metal was carried out followed by a mechanical polishing using a pianarizing polymeric layer. All organic layers were then removed to create a metallic hollow microneedle array with a fluidic reservoir on the backside. Both $200{\mu}m\;and\;400{\mu}m$ tall, 10 by 10 arrays of metallic microneedles with inner diameters of the tip in the range of $33.6{\sim}101\;{\mu}m$ and wall thickness of $10{\mu}m\;-\;20{\mu}m$ were fabricated. Analytic solutions of the critical buckling of arbitrary-angled truncated cone-shaped columns are also presented. It was found that a single $400{\mu}m$ tall hollow cylindrical microneedle made of electroplated nickel with a wall thickness of $20{\mu}m$, a tapered angle of $3.08^{\circ}$ and a tip inner diameter of $33.6{\mu}m$ has a critical buckling force of 1.8 N. This analytic solution can be used for square or rectangular cross-sectioned column structures with proper modifications.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.34 no.4
• /
• pp.409-416
• /
• 2010

The use of oxy-fuel combustion and flue gas recirculation (FGR) for $CO_2$ reduction has been studied by many researchers. This study focused on the characteristics of oxy-fuel combustion and the effects of $CO_2$ addition from the point of view of oxygen feeding ratio (OFR) and the position of $CO_2$ addition in order to reproduce an FGR system with a triple concentric multi-jet burner. Oxy-fuel combustion was stable at all OFRs at a fuel flow-rate of 15 lpm, which corresponds to an equivalence ratio of 0.93; however, the structure and length of the flame varied at different OFRs. When $CO_2$ was added in oxy-fuel combustion, various stability modes such as stable, transient, quasistable, unstable, and blow-out were observed. The temperature in the combustion chamber decreased upon $CO_2$ addition in all conditions, and the maximum reduction in temperature was below 1800 K. $CO_2$ concentration with respect to height varied with the volume percent of $CO_2$ at the nozzle tip.

• Animal Systematics, Evolution and Diversity
• /
• v.5 no.1
• /
• pp.77-88
• /
• 1989

Genetic and morphometric comparison between two species of the genus Agkistrodon were performed to estimate the degree of genic variation and to clarify the taxonomic status of Cheju population, a suspected hybrid form between A. blomhoffii brevicaudus and A u ussuriensis. A sum of 147 specimens representing six populations of A.b. brevicaudus and two populations of A ussuriensis was used in this study. Out of the 21 loci examined, 5 loci (Adh, Ldh-2, Mdh-2, Mpi, Pgi) were monomorphic with identical mobility in both species. O Other Sioci (Aco, Gp, Fum, [po and Xdh in A b. brevicaudus; Est, Got-l, Gp, Mdh-l and 6Pgd in A ussuriensis) were highly poplymorphic. The degree of genic variation of Ab. b brevicaudus and A ussuriensis was A=1.SS, P=42.1%, HD=0.096, HG=O.l1S, and A= 1.4S, P = 31.6%, HD=0.117, HG =0.121, repectively. These values are twofold higher t than those of other reptilian species reported (Selander, 1976) including Korean species of Rhabdophis tigrina and Elaphe dione (Paik and Yang, 1986, 1987). The average values of t the genetic similarities among six populations of A b. brevicaudus and two populations of A ussuriensis were S=0.919 and S=0.962, respectively, whereas the value between species was S = 0.662. Presumed divergent time estimate (Nei, 1975) of these two species was about 1 1.8 million years ago. The analysis of the geographic variations of various morphological c characters was based on Gloyd’s criteria (Gloyd, 1972). Coloration of tongue and tail tip, t the number of ventral scales, and the number of subcaudal scales are good diagnostic c characters to identify these two species. The pattern of cross band is, however, highly variable within and between populations of both species. No hybrid was detected and the s suspected hybrid form of Cheju population falls within the range of A. ussuriensis in the g genetic and morphometric analyses.

• Archives of Plastic Surgery
• /
• v.35 no.5
• /
• pp.589-596
• /
• 2008

Purpose: The nasal bone fracture is most common fracture in facial bone injuries. Regardless of the severity or type of fracture, closed reduction has traditionally been the common method of treatment. However, through detailed pre-operative evaluation, we found out that many patients consider rhinoplasty prior to trauma due to aesthetic desire or nasal deformity with or without septal deviation. In treatment of nasal bone fracture, we focused not only on the fracture management but also on the patients' desire prior to trauma, and we made additional operation according to patients' desire with fracture reduction and gained rewarding outcomes. Methods: From March 2005 to June 2007, total 263 patients were treated for nasal bone fracture. Among these patients, 57 patients (21%) had the additional operation with nasal fracture reduction. The additional operations were categorized in three types: augmentation rhinoplasty with tip plasty (40%), septoplasty only (16%), corrective rhinoplasty (44%). The mean follow-up period was 5.6 months and results were evaluated by scoring. Results: Forty four of 57 patients (77%) were highly satisfied regardless of any additional operation kinds. The complications were one septal perforation, two displacement of implant and four remnant nasal deformities. For the septal perforation, no further management was performed because we lost the contact with the patient. Then 4 of the other complicated patients were revised. Conclusion: In general, many physicians tend to consider nasal fracture as a simple trauma. However through the strict history taking, physical examination and professional counseling, we could catch the patient's cosmetic desire and get the eyes on new concept: the nasal fracture is not only a trauma but a cosmetic and functional field. In the treatment of nasal bone fracture, if additional rhinoplasty is performed, patients will be more satisfied and we also can expect higher profits.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.22 no.1
• /
• pp.23-46
• /
• 2020

In the current work, a series of three-dimensional finite element analyses have been carried out to understand the behaviour of pre-existing single piles to adjacent tunnelling by considering the tunnel face pressures and the relative location of pile tips with respect to the tunnel. The numerical modelling has analysed the effect of the face pressures on the pile behaviour. The analyses concentrate on the ground settlements, the pile head settlements, the axial pile forces and the shear stress transfer mechanism at the pile-soil interface. The head settlements of the pile (the vertical distance between the pile and the tunnel: 0.25D, where D is the tunnel diameter) directly above the tunnel crown with the face pressure 50% of the in-situ horizontal soil stress at the tunnel springline decreased by about 38% compared to corresponding settlements with a face pressure 25% of the in-situ horizontal soil stress at the tunnel springline. Furthermore, it was found that the smaller the face pressure, the larger the tunnelling-induced ground movements and the axial pile forces were and the higher the degree of the shear strength mobilisation at the pile-soil interface. When the piles were outside the tunnel influence zone, compressive pile forces were developed due to tunnelling. It has been found that the ground settlements and the pile settlements are heavily affected by the face pressures and the position of the pile tip relative to the tunnel. In addition, the computed results have been compared with relevant studies previously reported in literature. The behaviour of the piles has been extensively examined and analysed by considering the key features in great detail.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.9 no.1
• /
• pp.75-82
• /
• 2007

As one of the main support systems, rock bolts play a crucial role in the reinforcement of tunnels. Numerical and experimental studies using a transmission method of ultrasonic guided waves are performed to evaluate the integrity of rock bolts encapsulated by grouting paste. Numerical simulations using "DISPERSE" are carried out for the selection of the optimal experimental setup, i.e. non-destructive testing (NDT) system of the rock bolt. Based on results of the numerical simulation, the calculated frequency range for NDT testing is between 20kHz and 70kHz with the first longitudinal L(1) mode. Laboratory transmission tests are performed by attaching the piezo electric sensor at the tip of the rock bolt before embedding. Both of analytical and experimental results show that the amplitude of signals as well as the wave velocity increases with increase in the defect ratio of grouting paste. The defect in grouting paste means that the space around the rock bolt is not fully filled with the grouting paste. Experimental results also show that the increase of the wave velocity is more sensitive to the defect ratio increase than that of the amplitude. This study demonstrates that the transmission technique of ultrasonic guided waves may be a valuable tool in the evaluation of the rock bolt integrity.