• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.6
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• pp.1211-1216
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• 2002

To evaluate whole-body vibration(WBV) exposure and fatigue-decreased proficiency(FDP) boundary in passenger car driver, several roads in Busan were divided into 3 types by the condition of road surface; Road 1 was partially damaged, Road 2 was normal without damage, and Road 3 was better than Road 2. The results were following: The highest passenger driver's exposures to whole-body vibration acceleration and fatigue-decreased proficiency boundary at 40km/h were 0.108m/s² and about 2099 minutes in Road 2 for xh axis, 0.134m/s² and about 1585 minutes in Road 2 for yh axis, and 0.183m/s² and about 1053 minutes in Road 2 for zh axis, respectively. The highest passenger driver's exposures to whole-body vibration acceleration and fatigue-decreased proficiency boundary at 80km/h were 0.219m/s² and about 830 minutes in Road 3 xh axis, 0.203m/s² and about 918 minutes in Road 3 for yh axis, and 0.622m/s² and about 195 minutes in Road 1 for zh axis, respectively. The highest vector sums of whole-body vibration exposure at 40km/h and 804km/h were 0.328m/s² in Road 2 and 0.730m/s² in Road 1, respectively. The highest crest factors at 40km/h were 4.25 in Road 1 for xh, 4.51 in Road 3 for yh, and 5.81 in Road 2 for zh, respectively. The highest crest factors at 80km/h were 5.57 in Road 1 for xh, 5.60 in Road 2 for yh, and 6.46 in Road 3 for zh, respectively. The highest transmissibilities of whole-body vibration from floor to seat at 40km/h and 80km/h were 0.89 in Road 3 and 0.82 in Road 3 for xh axis, 0.83 in Road 3 and 0.87 in Road 1 and 2 for yh, and 0.80 in Road 2 and 0.92 in Road 1 tor zh axis, respectively. The highest fatigue-decreased proficiency boundaries for whole-body vibration exposure of passenger car driver in floor and seat were 457 minutes in Road 3 and 583 minutes in Road 3 at 40km/h and 159 minutes in Road 2 and 251 minutes in Road 2 at 80km/h, respectively.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.9
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• pp.859-866
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• 2010

Nonlinear dynamics of pulsating instability-diffusional-thermal instability with Lewis numbers sufficiently higher than unity-in counterflow diffusion flames, is numerically investigated by imposing a Damkohler number perturbation. The flame evolution exhibits three types of nonlinear behaviors, namely, decaying pulsating behavior, diverging behavior (which leads to extinction), and stable limit-cycle behavior. The stable limit-cycle behavior is observed in counterflow diffusion flames, but not in diffusion flames with a stagnant mixing layer. The critical value of the perturbed Damkohler number, which indicates the region where the three different flame behaviors can be observed, is obtained. A stable simple limit cycle, in which two supercritical Hopf bifurcations exist, is found in a narrow range of Damkohler numbers. As the flame temperature is increased, the stable simple limit cycle disappears and an unstable limit cycle corresponding to subcritical Hopf bifurcation appears. The period-doubling bifurcation is found to occur in a certain range of Damkohler numbers and temperatures, which leads to extend the lower boundary of supercritical Hopf bifurcation.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.880-894
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• 2010

The Grout injected precast pile is widely used in rapid-transit railway bridge recently. The existing portland cement of well used filling at injected precast method that with low strength and environmental pollution, unstable in which ground water contamination by cement flow out, ground relaxation by water down, decrease of horizontality resistance and durability and load transfer divide etc. In particular, as in rapid-transit railway bridge need to secure safety from different angle with vibration of high speed train, horizontal force when train stop and earthquake. Works of foundation construction consider to requirements of the times to coal yard green growth. Together, new green foundation method for possible economics and securing of reduce the term of works are material to developments. Therefore, we carried out study that it is using and development new concept environment - friendly filling include durability and earthquake resistance, for secure safety and minimize environment pollution. To achieve this, we carried out difference tests that new green fillings of underwater concrete, high liquidity, high viscosity, early stiffness as compared to existing portland cement fillings. As results, new green filling have outstanding application at precast pile method and micropile construction method with vertical bearing capacity, horizontal bearing capacity and many case. From now on we will be looking forward to development of new environment-friendly foundation method from various further studies.

• Korean Journal of Optics and Photonics
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• v.21 no.1
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• pp.21-25
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• 2010

In this paper, in order to enhance the image reconstruction performance of white light scanning interferometry(WLI), we demonstrate the scattered point noise filtering performance of post-processing methods. Median filtering is similar to using an averaging filter. Because the median value is less sensitive than the mean to extreme values, the median filter can remove the scattered point noise from a height-map without significantly reducing the sharpness of the image. In several specific cases, however, the median filter can't remove the scattered point noise. Therefore, we propose a comparative mean filter that uses order-statistic filtering and the mean of the neighborhood pixels. The performance is demonstrated by measuring an array of metal solder balls fabricated on PCB. The proposed method reduced the noise pixels by 4.4 percent.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.777-783
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• 2015

Wood is an anisotropic material that shows the changes in hardness, quality and dimensions depending on the types of cells on three cross sections, size, array and so on. It can also be used in different ways according to its use, which requires a meticulous research, in order to maximize the utilization by understanding the nature and use; and by clarifying the theory and technologies. The research on relationship among wood's physical properties, density, and elasticity of modulus have been studied in Korea and abroad, but those studies were based on correlation gained through standardized specimen. Rather, the study on complete product is rare. Moreover, the previous reports are mostly concentrating on vibration mode and batting, though the wood's physical properties as a material have not been in the main focus. Therefore, this study will carried out for analyzing MOE through figuring material property out and comparing frequency adapting to the Canadian HardMaple bat. For comparison of material properties, we studied the annual ring and density of the bat; calculated the MOE with resonance frequency and formula (ASTM C1259); and verified the repulsive force of this material. As a result, the relevance of the resonance frequency and annual ring is weak, and in comparison in the grain direction in wood, the MOE value is higher when the grain direction in wood is excited horizontally than when is excited vertically, because the material is repulsive when grain direction is horizontal.

• Journal of the Korean Applied Science and Technology
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• v.35 no.2
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• pp.485-491
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• 2018

The purpose of this study was to probe the influences of krill (Euphausia superba) meal supplementation on a dose effect relationship between fluoride levels of krill meal and serum hepatic functional enzyme activity such as alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) in rats fed experimental diets for 5 weeks. There were no significant differences in the activities of ALP, AST, ALT, and LDH in sera among krill meal diet groups (KM10, KM20, KM30). However, these groups were significantly (p<0.05) lower enzyme activities than control group (CG). The fluoride levels of sera and organ tissues (liver, brain, heart, lung, kidney) in krill meal diet groups (KM10, KM20, KM30) were significantly increased by adding krill meal in comparison with CG. The results indicate that a difficult to found toxicity to the liver from krill meal diet groups.

• Journal of Korean Society of Forest Science
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• v.81 no.1
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• pp.21-29
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• 1992

This study was conducted to provide basic information for deciding silvicultural system appropriate to a natural mixed stand in Jindong-Ri. For this, the stand structure such as DBH distribution, height distribution, and volume per DBH class were analyzed and the possibility of selection cutting as a silvicultural system was discussed. The DBH structure of the stand has reverse J-shaped diameter distribution which is typical in a selection cutting stand. The possibility of selection cutting is also accepted in the height structure by showing multi-storied height distribution of the stand. On the other hand, volume structure per DBH class did not show the mature stand of selection cutting due mainly to the lack of number of trees at 30cm DBH class and above. It seems that the unclear part of stand structure should be solved by further studies. Also, the rate of increment for DBH and volume should be estimated to predict the future stand structure.

• Journal of Korea Water Resources Association
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• v.47 no.12
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• pp.1227-1237
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• 2014

Dual-polarization can distinguish precipitation type and dual-polarization is provide not only meteorological phenomena in the atmosphere but also non-precipitation echoes. Therefore dual-polarization radar can improve radar estimates of rainfall. However polarimetric measurements by transmitting vertically vibration waves and horizontally vibrating waves simultaneously is contain systematic bias of the radar itself. Thus the calibration bias is necessary to improve quantitative precipitation estimation. In this study, the calibration bias of reflectivity (Z) and differential reflectivity ($Z_{DR}$) from the Bislsan dual-polarization radar is calculated using the 2-Dimensional Video Disdrometer (2DVD) data. And an improvement in rainfall estimation is investigated by applying derived calibration bias. A total of 33 rainfall cases occurring in Daegu from 2011 to 2012 were selected. As a results, the calibration bias of Z is about -0.3 to 5.5 dB, and $Z_{DR}$ is about -0.1 dB to 0.6 dB. In most cases, the Bislsan radar generally observes Z and $Z_{DR}$ variables lower than the simulated variables. Before and after calibration bias, compared estimated rainfall from the dual-polarization radar with AWS rain gauge in Daegu found that the mean bias has fallen by 1.69 to 1.54 mm/hr, and the RMSE has decreased by 2.54 to 1.73 mm/hr. And estimated rainfall comparing to the surface rain gauge as ground truth, rainfall estimation is improved about 7-61%.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.3
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• pp.81-90
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• 2013

The purpose of this paper is to do GIS-based suitable site selection using Scope for Growth index of Styela clava in Jindong Bay. The aquaculture of Styela calva is only conducted in Korea, especially Jindong Bay. Suspended culture of Styela clava was initiated in 2001 and the annual production reached 15,084M/T, but declined to 1,412M/T in 2005. The annual production was increased slightly to 2,484M/T in 2012 but the production is lower than the beginning yield. Scope for Growth(SFG) can indicate interrelationships between environment and organism growth index in aquaculture. GIS-based suitable site selection can be available by the concept of SFG, and fishery management system can be constructed for the sustainable production. As a result of the assessment of habitat suitability, Jindong Bay's SFG value ranges 0.054~0.57J/day and Styela clava farm's SFG values range 0.054~0.57J/day, either. The correlation between Styela clava farm's SFG and the actual production has a good result, as r=0.786, p<0.05. The construction of fishery management system using habitat suitability index ensures the reasonable site selection and the sustainable production in aquaculture farm. It introduces an objective method for the interrelationships between the environmental variation and the organism growth. Consequently, it can promote the decision making practices for the sustainable fishery management.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.15 no.1
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• pp.44-48
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• 2015

Mucopolysaccharidosis (MPS) IIIA is a lysosomal storage disorder caused by abnormalities of the enzyme Heparan N-sulfatase that is required for degradation of heparan sulfate. The patient in this study was a 5 year-old boy who presented with macrocephaly and developmental delay. Urinary excretion of glycosaminoglycan was increased (26 g/moL creatinine, reference range: <7 g/moL creatinine) and a distinct band of heparan sulfate was shown in electrophoresis. Heparan N-sulfatase activity was significantly decreased in skin fibroblasts (0.2 pmoL/min/mg protein, reference range: 9-64 pmoL/min/mg protein). PCR and direct sequencing analysis of the SGSH gene showed compound heterozygous mutations: c.1040C>T (p.S347F) and c.703G>A (p.D235N). This is the first report for a Korean patient with MPS IIIA who was confirmed by biochemical investigation and molecular genetic analyses.