• Journal of the Korean GEO-environmental Society
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• v.13 no.1
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• pp.63-74
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• 2012

In Korea, grouting has been mostly designed and constructed by experiences without expert knowledge and theoretical study. So there are a lot of problems related to the quality and safty of grouting. Therefor, in this paper the quality management skills and method were discussed through out by using the auto-grouting method and field test of grouting for the construction. Through the limit water injection test of the soil, it make the optimum injection pressure and injection speed of grouting, and through the lugeon test of the rock, it make assess the permeability of before and after grouting. In order to prevent the hydraulic fracture of soil and break away from the grouts if it apply four kinds of mode of grouting stop criteria, injection effects can be improved. From the above characteristcs designers evalute the fitness values of injection pressure(p), injection speed(q) and grouting penetration time(t). So far, to record and manage pressure(p) and speed(q) of grouting autographic devices such as intergation flow-meter usually record data in a roll of paper. Intergration flow-meter can record grouting flow quantity exactly, but the recorded pressures differ from the any basis such as intitial, intermediate and final point. Therefore, it has been argued that is a need of reliable method to describe the connection between the pressure recorded by an intergration flow-meter and the special properties of the grouting target ground. auto-grouting method can describe the reliable connection between the grouting pressure and the special properties of the grouting target ground. So, in this paper by using auto-grouting method, it is expected that to secure basis of quality control techniques construction.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.2
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• pp.158-165
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• 2016

The purpose of this study was to analyze photoplethysmographic waveforms from pulse oximeter using raw data of red and infrared light and investigate the reference values of parameters (Height, Width50, Maximum slope, Minimum slope, Area) for evaluating pulpal blood flow in maxillary central incisors with normal pulp vitality in children. The study was performed in 30 pediatric patients, aged 7-16 years old, using pulse oximeter (MEKICS Co., Ltd, Korea) combined with a custom-made sensor. The raw data was obtained and recorded by custom-made software and analyzed by LabChart (v.7.3, ADInstruments, Germany) offline. In this study, we analyzed photoplethysmographic waveforms from pulse oximeter applied to maxillary central incisor for assessment of pulpal blood flow and suggested several reference values of young permanent maxillary central incisor with normal pulp. On average, the waveform of red light was higher, stiffer and wider than that of infrared light. Future studies about reference values for other normal teeth and the teeth with impaired pulp vitality are needed.

• Magazine of the Korean Society of Agricultural Engineers
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• v.8 no.1
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• pp.1011-1034
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• 1966

This thesis is the final report which has long been studied by the author to obtain the design basis for various hydrological constructions with the specific system suitable to the natural environmental conditions in Korea. This report is divided into two parts: one is to estimate runoff volume from watersheds and the other to estimate the peak discharge for a single storm. According to the result of observed runoff record from watersheds, it is known that Kajiyama formula is useful instrument in estimating runoff volume from watersheds in this country. But it has been found that this formula shows us 20-30% less than the actual flow. Therefore, when wihed to bring a better result, the watershed characteristics coefficient in this formula, that is, f-value, should be corrected to 0.5-0.8. As for the method to estimate peak discharge from drainage basin, the author proposes to classify it in two ways; one is small size watershed and the other large size watershed. The maximum -flood discharge rate $Q_p$ and time to peak Pt obtained from the observed record on the small size watershed are compared by various methods and formulas which are based upon the modern hydrological knowledge. But it was fou.d that it. was not a satisfied result. Therefore, the author proposes. tocomputate $Q_p$, to present 4.0-5.0% for the total runoff volume ${\Sigma}Q$.${\Sigma}Q$ is computed under the assumption of 30mm 103s in watershed per day and to change the theoritical total flow volume to one hour dura tion total flow rate when design daily storm is given. Time to peak Pt is derived from three parameters which are u,w,k. These are computed by relationship between total runoff volume (ha-m unit)and $Q_p$. (C.M.S. unit). Finally, the author checked out these results obtained from 51 hydrographs and got a satisfied result. Therefore the author suggested the model of design dimensionless unit-hydrograph. And the author believes that this model will be much available at none runoff record river site. In the large size watersheds in Korea when the maximum discharge occurs, the effective rainfall is two consequtive stormy days. So the loss in watershed was assutned as 6Omm/2days,and the author proposed 3-hour-daration hydrograph flow distribution percentage. This distribution percentage will be sure to form the hydrograph coordinate.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.4
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• pp.284-288
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• 2009

With explosively growing PPI databases, the computational approach for a prediction and configuration of PPI network has been a big stream in the bioinformatics area. Recent researches gradually consider physicochemical properties of proteins and support high resolution results with integration of experimental results. With regard to current research trend, it is very close future to complete a PPI network configuration of each organism. However, direct applying the PPI network to real field is complicated problem because PPI network is only a set of co-expressive proteins or gene products, and its network link means simple physical binding rather than in-depth knowledge of biological process. In this paper, we suggest a protein functional flow model which is a directed network based on a protein functions' relation of signaling transduction pathway. The vertex of the suggested model is a molecular function annotated by gene ontology, and the relations among the vertex are considered as edges. Thus, it is easy to trace a specific function's transition, and it can be a constraint to extract a meaningful sub-path from whole PPI network. To evaluate the model, 11 functional flow models of Homo sapiens were built from KEGG, and Cronbach's alpha values were measured (alpha=0.67). Among 1023 functional flows, 765 functional flows showed 0.6 or higher alpha values.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.2
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• pp.219-235
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• 2014

With the development of the technology of underwater moving bodies, the need for developing the knowledge of surface effect interaction of free surface and underwater moving bodies is increased. Hence, the two-phase flow is a subject which is interesting for many researchers all around the world. In this paper, the non-linear free surface deformations which occur during the water-exit of a circular cylinder due to its buoyancy are solved using finite volume discretization based code, and using Volume of Fluid (VOF) scheme for solving two phase flow. Dynamic mesh model is used to simulate dynamic motion of the cylinder. In addition, the effect of cylinder mass in presence of an external force is studied. Moreover, the oblique exit and entry of a circular cylinder with two exit angles is simulated. At last, water-exit of a circular cylinder in six degrees of freedom is simulated in 3D using parallel processing. The simulation errors of present work (using VOF method) for maximum velocity and height of a circular cylinder are less than the corresponding errors of level set method reported by previous researchers. Oblique exit shows interesting results; formation of waves caused by exit of the cylinder, wave motion in horizontal direction and the air trapped between the waves are observable. In 3D simulation the visualization of water motion on the top surface of the cylinder and the free surface breaking on the front and back faces of the 3D cylinder at the exit phase are observed which cannot be seen in 2D simulation. Comparing the results, 3D simulation shows better agreement with experimental data, specially in the maximum height position of the cylinder.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.2
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• pp.125-135
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• 2005

Generation and transport of nonpoint source pollution, especially sediment-associated pollutants, are profoundly influenced by hydrologic features of runoff. In order to identify pollutant export rates, hence, clear knowledge of rainfall-runoff relationship is a pre-requisition. In this study, performance of AnnAGNPS model was assessed based on the ability of the model to predict rainfall-runoff relationship. Three catchments, each under different nearly single land use, were simulated. From the results, it was found that the model was likely to produce better predictions for larger catchments than smaller catchments. Because of using the daily time scale, the model could not account for short durations less than 24 hours, especially high intensity events with multiple peak flow that significantly contribute to the generation and transport of pollutants. Since CN information for regional areas has not been built up, a careful selection of CN is needed to achieve accurate prediction of runoff volume. Storm distribution also found to be considered as an important calibration parameter for the hydrologic simulation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.1173-1178
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• 2004

Gagamhwanglyeonhaedog-tang(GHH), a Korean genuine medicine, is a newly designed herbal drug formula based on the traditional oriental pharmacological knowledge for the purpose of treating tumorous diseases. Apoptosis is an evolutionarily conserved suicide program residing in cells. It leads to cell death through a tightly regulated process resulting in the removal of damaged or unwanted tissue. In the present study, the apoptosis inducing activities of the decocted water extract of GHH were studied. Results of the 3- [4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay showed that GHH had a strong cytotoxic effect on HL-60 cells. The number of live cells was less than 20% after exposure to 1㎎/㎖ GHH for 48 hr. GHH increased cytotoxicity of HL-60 cells in a dose- and time­dependent manner. Cell apoptosis by GHH was confirmed by flow cytometric analysis of the DNA-stained cells. The percentage of apoptotic cells increased to 28%, 31% and 37% 24 hr and 37%, 44% and 81% 48 hr after treatment with 0.01, 0.1 and 1㎎/㎖ GHH, respectively. Flow cytometric analysis of GHH treated HL-60 cells showed increase of hypodiploid apoptotic cells in a dose- and time- dependent manner. DNA fragmentation also occurred in apoptosis and was characterized by a ladder pattern on agarose gel. In addition, GHH (0.01 and 0.1㎎/㎖) increased the secretion of tumor necrosis factor-alpha in 24 and 48 hr. The author showed that GHH-induced apoptosis was accompanied by activation of caspase-3. These results suggest that GHH induces activation of caspase-3 and eventually leads to apoptosis.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2001.10a
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• pp.25-28
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• 2001

Today enterprises are bringing forward the strong needs for the Global Work Space that is able to realize the collaboration of the virtual enterprise in order to achieve the rapid entrance to market, the quality improvement as well as the cost reduction of their new products. Especially, they are building the efficient Product Management Infrastructure in parallel with the real-time knowledge management for the information generated in the course of a product lifecycle and the Process Innovation making the Concurrent Engineering possible. Building a system in the web environment cannot be the entire effort to realize the Global Work Space within an enterprise that is an essential factor for the reduction of a product development period which in turn contributes to Time to Market. Various work models and processes are found in enterprises and many different application programs are developed and utilized to support these. This study proposes a scheme for the optimized Collaborative Workflow System Architecture that is able to take in and apply various application programs accompanied by the product development work process. Through this, we are to examine various limits and problems existing in the real-time collaborative system between enterprises and to reform these.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.1
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• pp.35-40
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• 2017

A most important progress in civilization was the introduction of mass production. One of main methods for mass production is die-casting molds. Due to the high velocity of the liquid metal, aluminum die-casting is so complex where flow momentum is critical matter in the mold filling process. Actually in complex parts, it is almost impossible to calculate the exact mold filling performance with using experimental knowledge. To manufacture the lightweight automobile bodies, aluminum die-castings play a definitive role in the automotive part industry. Due to this condition in the design procedure, the simulation is becoming more important. Simulation can make a casting system optimal and also elevate the casting quality with less experiment. The most advantage of using simulation programs is the time and cost saving of the casting layout design. For a die casting mold, generally, the casting layout design should be considered based on the relation among injection system, casting condition, gate system, and cooling system. Also, the extent or the location of product defects was differentiated according to the various relations of the above conditions. In this research, in order to optimize the casting layout design of an automotive Oil Pan_BR2E, Computer Aided Engineering (CAE) simulation was performed with three layout designs by using the simulation software (AnyCasting). The simulation results were analyzed and compared carefully in order to apply them into the production die-casting mold. During the filling process with three models, internal porosities caused by air entrapments were predicted and also compared with the modification of the gate system and overflows. With the solidification analysis, internal porosities occurring during the solidification process were predicted and also compared with the modified gate system.

• Corrosion Science and Technology
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• v.14 no.1
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• pp.19-24
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• 2015

Flow Accelerated Corrosion (FAC) causes unexpected accidents in a secondary side of a nuclear power plant. The secondary side pipes are mainly carbon steel tubes that have a protective magnetite ($Fe_3O_4$) layer on the inner surface. The stability of the protective magnetite layer depends on the parameters related to the FAC phenomena such as pH, temperature, flow rate, surface roughness etc. The dissolution of magnetite is basically the electrochemical reaction, but the most of the experiments of magnetite dissolution were carried out thermodynamically to determine the solubility of magnetite. The knowledge of the electrochemical properties of magnetite is required to understand the dissolution process of magnetite. This paper reviews the manufacture of the magnetite ($Fe_3O_4$) electrode, and summaries the electrochemical properties of the magnetite.