• Journal of Korean Society for Atmospheric Environment
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• v.33 no.5
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• pp.497-514
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• 2017

This study quantitatively analyzes the effects of emission inventory choices on the simulated particulate matter (PM) concentrations and the domestic/foreign contributions in the Seoul Metropolitan Area (SMA) with an air quality forecasting system. The forecasting system is composed of Weather Research and Forecasting (WRF)-Sparse Matrix Operator Kernel Emissions (SMOKE)-Community Multi-Scale Air Quality (CMAQ). Different domestic and foreign emission inventories were selectively adopted to set up four sets of emissions inputs for air quality simulations in this study. All modeling cases showed that model performance statistics satisfied the criteria levels (correlation coefficient >0.7, fractional error <50%) suggested by previous studies. Notwithstanding the apparently good model performance of total PM concentrations by all emission cases, annual average concentrations of simulated total PM concentrations varied up to $20{\mu}g/m^3$ (160%) depending on the combination of emission inventories. In detail, the difference in simulated annual average concentrations of the primary PM coarse (PMC) was up to $25.2{\mu}g/m^3$ (6.5 times) compared with other cases. Furthermore, model performance analyses on PM species showed that the difference in the simulated primary PMC led to gross model overestimation in general, which indicates that the primary PMC emissions need to be improved. The contribution analysis using model direct outputs indicated that the domestic contributions to the annual average PM concentrations in the SMA vary from 44% to 67%. To account for the uncertainty of the simulated concentration, the contribution correction factor method proposed by Bae et al. (2017) was applied, which resulted in converged contributions(from 48% to 57%). We believe this study shows that it is necessary to improve the simulated concentrations of PM components in order to enhance the accuracy of the forecasting model. It is deemed that these improvements will provide more accurate contribution results.

• The Journal of Korean Academy of Prosthodontics
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• v.28 no.2
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• pp.91-108
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• 1990

The purpose of this study was to compare the maganitude of the discrepancies of the mounting errors in according to the states of dentitions, and to the superoinferior, anteroposterior, and rightleft driecetions. GROUP I. : Fourteen patients 22 to 26 years of age with a full complement of teeth, were used in the study. The criteria fro patient selection were a complete dentition, sparse restorarive treatment, and adequate posterior and anterior occlusan stops. And they had no sign and sympton at TMG area. GROUPII. : Eigth patients 37 to 62 years of age with bilateral free ends. The criteria for patient selection were Kennedy classification class 1 cases, and adequate posterior and anterior stops. And the opposite dentitions were a full complement of teeth. Irreversible hydrocolloid impresiion of each arch was taken of each patient. These were immediatel poured in stone and mounted on a Denar Mark II. Articulator with the arbitrary slidematic face-bow. With hand articulation th e mandibular cast was mounted to the maxillary cast in centric occlusion. Five types of interocclusal records were taken of each patient : (1) aluwax (2) baseplate wax; (3) znic oxide-eugenol pasts; (4) polyether (Ramitec); (5) modeling compound. All measurement of the five selected recording materials were compared with those of the hand-articulated full arch models in centric occlusion or maximum interdigitation. The results were as follows; 1. There were statistical differences in amount of devitation in according to the materials and the states of dentition. The amount of deviation of compound was the largest. 2. There were statistical differences in amount of deviation in complete dentition at all directions. The amount of diviation of compound was the largest. And at the right-left direction the amount of znic oxide-eugenol paste was larger than that of baseplate wax. 3. There was a statistical difference in amount of diviations in partial edentulous dentition at the superoinferior direction. The amount of deviation of compound was larger than that of znic oxide-eugenol paste. 4. There was as statistical difference in amount of deviations in partial edentulous dentition at the right-left direction. The amount of deviation of baseplate wax was larger that tnat of polyether. 5. There was not a statistical difference in amount of diviation in partial edentulous dentition at the anteroposterior direction.

• Journal of Korea Water Resources Association
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• v.46 no.7
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• pp.755-765
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• 2013

This study developed a real-time dam's hydrologic variables prediction model (DHVPM) and evaluated its performance for simulating historical dam inflow and outflow in the Chungju dam basin. The DHVPM consists of the Sejong University River Forecast (SURF) model for hydrologic modeling and an autoreservoir operation method (Auto ROM) for dam operation. SURF model is continuous rainfall-runoff model with data assimilation using an ensemble Kalman filter technique. The four extreme events including the maximum inflow of each year for 2006~2009 were selected to examine the performance of DHVPM. The statistical criteria, the relative error in peak flow, root mean square error, and model efficiency, demonstrated that DHVPM with data assimilation can simulate more close to observed inflow than those with no data assimilation at both 1-hour lead time, except the relative error in peak flow in 2007. Especially, DHVPM with data assimilation until 10-hour lead time reduced the biases of inflow forecast attributed to observed precipitation error. In conclusion, DHVPM with data assimilation can be useful to improve the accuracy of inflow forecast in the basin where real-time observed inflow are available.

• Korean Journal of Construction Engineering and Management
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• v.16 no.6
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• pp.124-135
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• 2015

As many countries have been raising awareness of environmental issues, greater efforts for eco-friendly construction have been made in both governmental and private sectors. However, assessment circumstances for building energy performance and green building standard of legislation are still based on two dimension and handwork. This takes time, cost and labor, and makes assessment inaccurate and inefficient. Therefore, this study suggests methods to improve eco-friendly construction permission process and to automatize open BIM-based assessment of Energy Performance Index (EPI) among several eco-friendly construction certification standards. First, it analyzes the relations between assessment criteria and IFC data, and provides solutions to problems and limitations. Second, it applies the solutions to assessment program in order to automatize open BIM-based assessment for EPI. The eco-friendly construction permission process with these solutions applied will reduce time, cost, and labor by simplifying and automatizing the tasks. Also, the simplified process of design revision will improve not only productivity and efficiency but also accuracy and reliability.

• Journal of the Korean Society of Radiology
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• v.18 no.2
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• pp.127-133
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• 2024

The elbow joint is made up of three different bones. X-rays or other radiological exams are commonly used to diagnose elbow injuries or disorders caused by physical activity and external forces. Previous research on the elbow joint reported a new examination method that meets the imaging evaluation criteria in the tilt position by Z-axis elevation of the forearm. Therefore, this study aims to design an optimized instrument and develop an aid applicable to other upper extremity exams. After completing the 2D drawing and 3D modeling design, the final design divided into four parts was fabricated with a 3D printer using ABS plastic and assembled. The developed examination aid consists of a four-stage Z-axis elevation tilt angle function (0°, 5°, 10°, and 15°) and can rotate and fixate 360° in 1-degree increments. It was designed to withstand a maximum equivalent stress of 56.107 Pa and a displacement of 1.6548e-5 mm through structural analysis to address loading issues caused by cumulative frequency of use and physical utilization. In addition to X-ray exams of the elbow joint, the developed aid can be used for shoulder function tests by rotating the humerus and also be applied to MRI and CT exams as it is made of non-metallic materials. It will contribute to the accuracy and efficiency of medical imaging diagnosis through clinical applications of various devices and medical imaging exams in the future.

• The Transactions of the Korea Information Processing Society
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• v.5 no.10
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• pp.2575-2583
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• 1998

The productionof the highly relible softwae systems and theirs performance evaluation hae become important interests in the software industry. The software evaluation has been mainly carried out in ternns of both reliability and performance of software system. Software reliability is the probability that no software error occurs for a fixed time interval during software testing phase. These theoretical software reliability models are sometimes unsuitable for the practical testing phase in which a software error at a certain testing stage occurs by causes of the imperfect debugging, abnornal software correction, and so on. Such a certatin software testing stage needs to be considered as an outlying stage. And we can assume that the software reliability does not improve by means of muisance factor in this outlying testing stage. In this paper, we discuss Bavesian software reliability growth modeling and estimation procedure in the presence of an imidentitied outlying software testing stage by the modification of Jehnski Moranda. Also we derive the Bayes estimaters of the software reliability panmeters by the assumption of prior information under the squared error los function. In addition, we evaluate the proposed software reliability growth model with an unidentified outlying stage in an exchangeable model according to the values of nuisance paramether using the accuracy, bias, trend, noise metries as the quantilative evaluation criteria through the compater simulation.