• Journal of the Korean Institute of Intelligent Systems
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• v.26 no.2
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• pp.93-98
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• 2016

For accurate precipitation forecasts the choice of weather factors and prediction method is very important. Recently, machine learning has been widely used for forecasting precipitation, and artificial neural network, one of machine learning techniques, showed good performance. In this paper, we suggest a new method for forecasting precipitation using DBN, one of deep learning techniques. DBN has an advantage that initial weights are set by unsupervised learning, so this compensates for the defects of artificial neural networks. We used past precipitation, temperature, and the parameters of the sun and moon's motion as features for forecasting precipitation. The dataset consists of observation data which had been measured for 40 years from AWS in Seoul. Experiments were based on 8-fold cross validation. As a result of estimation, we got probabilities of test dataset, so threshold was used for the decision of precipitation. CSI and Bias were used for indicating the precision of precipitation. Our experimental results showed that DBN performed better than MLP.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.425-435
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• 2017

Structural analysis is used not only for large enterprises, but also for small and medium sized ones, as a necessary procedure for strengthening the certification process for product delivery and shortening the time in the process from concept design to detailed design. Open-source solvers that can be used atlow cost differ from commercial solvers. If there is a problem with the input data, such as with the grid, errors or failures can occur in the calculation step. In this paper, we propose a pre- and post-processor that can be easily applied to the analysis of mechanical structural problems by using the existing structural analysis open source solver (Caculix, Code_Aster). In particular, we propose algorithms for analyzing different types of data using open source solvers in order to extract and generate accurate information,such as 3D models, grids and simulation conditions, and develop and apply information analysis. In addition, to improve the accuracy of open source solvers and to prevent errors, we created a grid that matches the solver characteristics and developed an automatic healing function for the grid model. Finally, to verify the accuracy of the system, the verification and utilization results are compared with the software used.

• The Journal of Advanced Prosthodontics
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• v.9 no.3
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• pp.176-181
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• 2017

PURPOSE. The purpose of this study was to evaluate the marginal and internal gaps of Ni-Cr and Co-Cr copings, fabricated using the dental ${\mu}-SLA$ system. MATERIALS AND METHODS. Ten study dies were made using a two-step silicone impression with a dental stone (type IV) from the master die of a tooth. Ni-Cr (NC group) and Co-Cr (CC group) alloy copings were designed using a dental scanner, CAD software, resin coping, and casting process. In addition, 10 Ni-Cr alloy copings were manufactured using the lost-wax technique (LW group). The marginal and internal gaps in the 3 groups were measured using a digital microscope ($160{\times}$) with the silicone replica technique, and the obtained data were analyzed using the non-parametric Kruskal-Wallis H test. Post-hoc comparisons were performed using Bonferroni-corrected Mann-Whitney U tests (${\alpha}=.05$). RESULTS. The mean (${\pm}$ standard deviation) values of the marginal, chamfer, axial wall, and occlusal gaps in the 3 groups were as follows: $81.5{\pm}73.8$, $98.1{\pm}76.1$, $87.1{\pm}44.8$, and $146.8{\pm}78.7{\mu}m$ in the LW group; $76.8{\pm}48.0$, $141.7{\pm}57.1$, $80.7{\pm}47.5$, and $194.69{\pm}63.8{\mu}m$ in the NC group; and $124.2{\pm}52.0$, $199.5{\pm}71.0$, $67.1{\pm}37.6$, and $244.5{\pm}58.9{\mu}m$ in the CC group. CONCLUSION. The marginal gap in the LW and NC groups were clinically acceptable. Further improvement is needed for CC group to be used clinical practice.

• Journal of The Korean Association of Information Education
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• v.20 no.6
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• pp.617-628
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• 2016

For the education on information, information appliances and operating systems of the information curriculum in elementary schools, precedent studies on the content structure of domestic and foreign curricula and etc. were compared and analyzed, and the ways of improvement and implications were examined. In addition, the necessity to select these contents, time of education, appropriateness of the selected contents were surveyed by professionals, and as the research results, the contents for the education on information, information appliances and operating systems in elementary schools were chosen, and achievement standards were set and proposed. The paper results can be used for the development of national level of elementary information curriculum and for the cultivation of elementary school students' key educational capacities. This paper has the limit that its results cannot be generalized because its analysis was based on the outcome surveyed only by some experts. Nevertheless, it is meaningful in that it specifically tried to analyze the appropriateness of the content achievement standards of the elementary information curriculum, and through which, it offers the information necessary for the stable management of elementary information curriculum and the improvement of elementary information curriculum.

• Journal of Digital Contents Society
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• v.18 no.6
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• pp.1183-1191
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• 2017

In order to support the service efficiently, a Science and Technology information platform that can share the same contents and technologies is needed. Therefore this study develop a platform that can use various contents and technologies as a common utilization factor, and support a fast and efficient service. In addition, It suggest examples of various APIs in a platform environment system that can utilize scientific data and technologies in various forms according to their use. Throughout the studies, various contents and technologies will be able to connect and interact with each other through the API Gateway on the platform, as well as to integrate Science and Technology contents based on identified researchers, institutions, and terminology data.

• Journal of KIISE:Software and Applications
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• v.31 no.3
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• pp.293-307
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• 2004

We consider the problem of scheduling tasks of a precedence constrained task graph, where each task has its execution time and deadline, onto a set of identical processors in a way that simultaneously minimizes the number of processors required and the total tardiness of tasks. Most existing approaches tend to focus on the minimization of the total tardiness of tasks. In another methods, solutions to this problem are usually computed by combining the two objectives into a simple criterion to be optimized. In this paper, the minimization is carried out using a multiobjective genetic algorithm (GA) that independently considers both criteria by using a vector-valued cost function. We present various GA components that are well suited to the problem of task scheduling, such as a non-trivial encoding strategy. a domination-based selection operator, and a heuristic crossover operator We also provide three local improvement heuristics that facilitate the fast convergence of GA's. The experimental results showed that when compared to five methods used previously, such as list-scheduling algorithms and a specific genetic algorithm, the Performance of our algorithm was comparable or better for 178 out of 180 randomly generated task graphs.

• Korean Journal of Construction Engineering and Management
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• v.17 no.2
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• pp.31-38
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• 2016

In a construction project, the portion for maintenance costs for a building is considerable compared to the initial construction cost. As such, Life Cycle Cost (LCC) analysis is being increasingly utilized to assess the design value of engineering work in Korea. Additionally, the Public Procurement Service in Korea announced that it will be mandatory for all domestic construction projects to adopt BIM. Furthermore, the paradigm for architectural design has shifted from 2D to 3D, and to BIM, which includes a data management system. Within this background, however, there is currently no adequate BIM-based LCC analysis software and the requirements of cost estimation for repair and replacement cost for a building is not completely adequate in BIM tools such as Revit and Archicad. Therefore, this study suggests a process of cost estimation for repair and replacement (R&R) cost based on IFC data. First, we analyzed existing R&R criteria and defined BIM-based requirements when calculating R&R costs. These requirements were extracted from relevant IFC data. Subsequently, this was saved to a database and a BIM-based database was built for R&R cost estimation. Finally, this database was connected with external databases such as R&R Criteria DB and Cost Information DB to calculate R&R costs. This process is expected to improve upon the traditional process of cost estimation of R&R cost by applying a BIM model. The proposed process can contribute to a further standardizing of BIM-based LCC analysis thru application to initial construction costs, energy costs, and other maintenance costs.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.6
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• pp.503-512
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• 2018

SAR(Synthetic Aperture Radar) is a technology to acquire images by processing signals obtained from radar, and there is an increasing demand for utilization of high-resolution SAR images. In this paper, for high-speed processing of high-resolution SAR image data, a study for SAR image processing algorithms to achieve optimal performance in multi-core based computer architecture is performed. The performance deterioration due to a large amount of input/output data for high resolution images is reduced by maximizing the memory utilization, and the parallelization ratio of the code is increased by using dynamic scheduling and nested parallelism of OpenMP. As a result, not only the total computation time is reduced, but also the upper bound of parallel performance is increased and the actual parallel performance on a multi-core system with 10 cores is improved by more than 8 times. The result of this study is expected to be used effectively in the development of high-resolution SAR image processing software for multi-core systems with large memory.

• The Korean Journal of Nuclear Medicine Technology
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• v.22 no.1
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• pp.28-34
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• 2018

Purpose With regard to the use of radioiodine in domestic medical institution, the case of exceeding the allowance of nuclear safety Act about radioactive concentration in drainage was found. Through understanding the cause of exceeding case and analyzing radioactive concentration in drainage, evaluating the relationship of the public waters in surroundings and usefulness. Materials and Methods From November 1, 2014 to April 30th, 2015, the research is aiming at domestic twenty hospitals for six months. By using a HPGe gamma-ray spectrometer(Canberra DSA-1000) and GENIE-2000 Analysis software for comparative analysis, measuring a radioactive concentration of radioiodine in drainage. Consequently, we confirm the excess of radioactive concentration of radioiodine in seven medical institutions. Results Conducting a survey of twenty hospitals and average radioactive concentration of radioiodine in drainage appears $42,100Bq/m^3$. The features of domestic hospitals where show a high radioactive concentration are a number of medical treatment patient when using radioactive iodine and the absence of private rest room. During I-131 whole body scan, the pretreatment procedure of urinating is considered emission of residual Iodine. In public waters, the cause of exceeding detect on radioactive concentration in drainage suppose a diagnostic radioactive iodine. Conclusion We confirm the importance of enhanced education, providing a safety control instructions and installing a private rest rooms for patients who injected a low capacity radioiodine. Also, constructing institutional and legal management system is considered about the Emission management standard in drainage.

• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.307-318
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• 2002

To provide a guideline for the development of a web-based sport biomechanics class in undergraduate program, thirty web sites, searched via search engines in May 2002, were analyzed intensively. In terms of requirement of log-in, only one site of 30 sites required user name and password. Seventeen(57%) sites provided the lecture note, which had various file formats such as 59% if PDF, 29% of HTML, and 12% of PPT. Fourteen(47%) sites provided the assignment and grade information on web. Eleven(37%) sites provided various resource and links which were related in sports biomechanics. Only four(13%) sites provided discussion or online digitizing or kinematic analysis program. Based on above results, a guideline for the development of a virtual classroom for college level sport biomechanics. A web-based sport biomechanics class should be developed with consideration of several functions as follows; homepage design, lecture note, measurement of class attendance, collaborative research system, and web-based data collection and analysis software for biomechanics laboratory.