• Journal of the Korea Safety Management & Science
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• v.21 no.1
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• pp.17-23
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• 2019

The diesel engine generate many pollutants such as PM(Particulate matter) and NOx(Nitrogen oxide). So the SCR(Selective catalytic reduction) must be required to meet the emission standard. The SCR catalyst market is growing rapidly, and the automobile markets using alternative energy sources are growing rapidly. This study deals with optimization of the calcination process the manufacturing process of SCR catalyst to be competitive. The calcination process is a bottleneck and it is required to optimize productivity and accept to be safety, But we cannot trade off anything in terms of safety. We applied DOE(Design of experiments) among many research methods performed in various fields. In order to achieve quality and productivity optimization. The dependent variables in the DOE were selected as NO Conversion(%). The independent variables were selected as the calcination temperature, soaking time and fan speed RPM. the CCD(Central composite designs) constructs response surface using the data onto experience and finds optimum levels within the fitted response surfaces. Our tests are our stability guarantee and efficient together with operation.

• Journal of Korea Society of Waste Management
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• v.35 no.7
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• pp.647-652
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• 2018

The emission of nitrogen oxides has a great environmental impact. It leads to Los Angeles type smog, and it recently has attracted attention as a source of ultrafine dust. The main sources of nitrogen oxides are internal combustion engines and industrial boilers. These emission sources are processes that are essential for human industrial activities, so the regulation of original use is impossible. Therefore, special control methods should be applied to reduce NOx emissions into the atmosphere. In this study, we investigated how the supply of ER and urea influences the removal of nitrogen oxides from SRF combustion boilers. Experimental results show that the removal efficiency of nitrogen oxides can be up to 80% under the conditions of ER 2.0 and a urea feed of 0.5 LPM.

• Health Policy and Management
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• v.32 no.3
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• pp.258-271
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• 2022

The rapidly aging trend of Korea is a major factor that threatens the sustainability of the long-term care insurance system. Therefore, looking at how Japan and Germany mitigated the financial burden when they managed similar long-term care insurance systems will provide important implications for improving the Korean system in the future. The study was conducted using the literature review method, and the "country" was set as a unit for the case analysis. The three countries selected are Korea, Japan, and Germany. Recently in Korea, the insurance premium rates of all subjects have been rapidly rising, which can exacerbate the issue of intergenerational equity. On the other hand, Japan has responded to the aggravating finances for long-term care insurance due to aging by raising coinsurance for selected groups like the wealthy elderly. Germany is selectively raising the insurance premium rates by additionally increasing the premium rate for childless recipients. A more preventive and quality-oriented care service plan can be promoted by referring to the recent changes in Japan and Germany. In addition, a more effective and selective increase in payment burden in Japan and Germany could be considered in response to a recent equity issue in Korea.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2001.01a
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• pp.133-141
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• 2001

Since the computing environment changes very rapidly, the estimation of software effort is very difficult because it is not easy to collect a sufficient number of relevant cases from the historical data. If we pinpoint the cases, the number of cases becomes too small. However is we adopt too many cases, the relevance declines. So in this paper we attempt to balance the number of cases and relevance. Since many researches on software effort estimation showed that the neural network models perform at least as well as the other approaches, so we selected the neural network model as the basic estimator. We propose a search method that finds the right level of relevant cases for the neural network model. For the selected case set. eliminating the qualitative input factors with the same values can reduce the scale of the neural network model. Since there exists a multitude of combinations of case sets, we need to search for the optimal reduced neural network model and corresponding case, set. To find the quasi-optimal model from the hierarchy of reduced neural network models, we adopted the beam search technique and devised the Case-Set Selection Algorithm. This algorithm can be adopted in the case-adaptive software effort estimation systems.

• Journal of Korea Society of Digital Industry and Information Management
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• v.19 no.1
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• pp.109-118
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• 2023

Data-based analysis methods have become used more for estimating or predicting housing prices, and neural network models and decision trees in the field of big data are also widely used more and more. Neural network models are often evaluated to be superior to existing statistical models in terms of estimation or prediction accuracy. However, there is ambiguity in determining the input feature of the input layer of the neural network model, that is, the type and number of input features, and decision trees are sometimes used to overcome these disadvantages. In this paper, we evaluate the existing methods of using decision trees and propose the method of using decision trees to prioritize input feature selection in neural network models. This can be a complementary or combined analysis method of the neural network model and decision tree, and the validity was confirmed by applying the proposed method to house price estimation. Through several comparisons, it has been summarized that the selection of appropriate input characteristics according to priority can increase the estimation power of the model.

• The Journal of Economics, Marketing and Management
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• v.12 no.1
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• pp.39-51
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• 2024

Purpose: This study aims to derive planning directions of community facilities integrating generations based on local communities to promote sustainable intergenerational exchange by analyzing the spatial configuration and programs of domestic and foreign generation-integrated community facilities based on local communities. Research design, data and methodology: Through theoretical consideration, the concept of intergenerational integration, types of intergenerational exchange, and spatial arrangement types were identified. Then, case study analysis of domestic and foreign community facilities with well-planned intergenerational exchange spaces and programs were conducted to identify intergenerational integration, and to derive community facility planning direction. Results: The results of this research are as follows. First, in terms of humanware, in order to revitalize continuous exchange between the 1st, 2nd, and 3rd generations, a systematic support system is needed to build mutual trust through voluntary participation by each generation. Second, it is important to provide a variety of shared spaces while maintaining the uniqueness of each facility from a hardware perspective, and must be planned in such a way that selective interaction takes place with privacy and interaction in mind. Third, in terms of software, programs that meet the characteristics of each user must be provided. Conclusions: It is expected that the results of this research can be used as basic data for planning community facilities that integrate generations based on local communities, contributing to the search for sustainable ways to revitalize intergenerational exchange in the future.

• Hip & pelvis
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• v.34 no.4
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• pp.191-202
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• 2022

The aim of this study was to provide helpful information for use in selection of an appropriate medication after osteoporotic fractures through conduct of a literature review. In addition, a review of the recommendations of several societies for prevention of subsequent fractures was performed and the appropriate choice of medication for treatment of atypical femur fractures was examined. Clinical perspective was obtained and an updated search of literature was conducted across PubMed and MEDLINE and relevant articles were selected. The articles were selected manually according to relevance, and the references for identified articles and reviews were also evaluated for relevance. The following areas are reviewed: Commonly prescribed osteoporosis medications: BPs (bisphosphonates), denosumab, and SERMs (selective estrogen receptor modulators) in antiresorptive medications and recombinant human parathyroid hormone teriparatide, recently approved Romosuzumab in anabolic agents, clinical practice guidelines for the management of osteoporosis, osteoporotic fracture, and atypical femur fracture. Most medications for treatment of osteoporosis do not delay fracture healing and the positive effect of teriparatide on fracture healing has been confirmed. In cases where an osteoporotic fracture is diagnosed, risk assessment should be performed for selection of very high-risk patients in order to prevent subsequent fractures, and administration of anabolic agents is recommended.

• Journal of Digital Convergence
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• v.13 no.8
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• pp.59-67
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• 2015

As online game addiction of youth becomes a serious social problem, various regulations restricting their game play have been introduced. However, it is considered that forced shut-down, selective shut-down, and other regulations have no effect, and theoretical debates about the necessity of regulations also continue. Therefore, this study theoretically re-examines the necessity of youth game regulations by the discussion on domestic and international policy trends and existing research. In order to confirm empirical evidence of the effectiveness of regulations, this study compares and analyses the change of youth's game play time and patterns before and after the regulations. According to the results, the effect of the regulations is inadequate so this study proposes reasonable improvement ways of them through convergent approach including legal, political, and technological perspective.

• Journal of Computational Design and Engineering
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• v.1 no.2
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• pp.103-115
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• 2014

The engineering design process is a creative process, and the designers must repeatedly apply Undo/Redo operations to modify CAD models to explore new solutions. Undo/Redo has become one of most important functions in interactive graphics and CAD systems. Undo/Redo in a collaborative CAD system is also very helpful for collaborative awareness among a group of cooperative designers to eliminate misunderstanding and to recover from design error. However, Undo/Redo in a collaborative CAD system is much more complicated. This is because a single erroneous operation is propagated to other remote sites, and operations are interleaved at different sites. This paper presents a multi-user selective Undo/Redo approach in full distributed collaborative CAD systems. We use site ID and State Vectors to locate the Undo/Redo target at each site. By analyzing the composition of the complex CAD model, a tree-like structure called Feature Combination Hierarchy is presented to describe the decomposition of a CAD model. Based on this structure, the dependency relationship among features is clarified. B-Rep re-evaluation is simplified with the assistance of the Feature Combination Hierarchy. It can be proven that the proposed Undo/Redo approach satisfies the intention preservation and consistency maintenance correctness criteria for collaborative systems.

• Journal of Korean Neurosurgical Society
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• v.53 no.4
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• pp.235-240
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• 2013

Fusiform aneurysms on the basilar artery (BA) trunk are rare. The microsurgical management of these aneurysms is difficult because of their deep location, dense collection of vital cranial nerves, and perforating arteries to the brain stem. Endovascular treatment is relatively easier and safer compared with microsurgical treatment. Selective occlusion of the aneurysmal sac with preservation of the parent artery is the endovascular treatment of choice. But, some cases, particularly giant or fusiform aneurysms, are unsuitable for selective sac occlusion. Therefore, endovascular coiling of the aneurysm with parent vessel occlusion is an alternative treatment option. In this situation, it is important to determine whether a patient can tolerate parent vessel occlusion without developing neurological deficits. We report a rare case of fusiform aneurysms in the BA trunk. An 18-year-old female suffered a headache for 2 weeks. Computed tomography and magnetic resonance image revealed a fusiform aneurysm of the lower basilar artery trunk. Digital subtraction angiography revealed a $7.1{\times}11.0$ mm-sized fusiform aneurysm located between vertebrovasilar junction and the anterior inferior cerebellar arteries. We had good clinical result using endovascular coiling of unruptured fusiform aneurysm on the lower BA trunk with parent vessel occlusion after confirming the tolerance of the patient by balloon test occlusion with induced hypotension and accompanied by neurophysiologic monitoring, transcranial Doppler and single photon emission computed tomography. In this study, we discuss the importance of preoperative meticulous studies for avoidance of delayed neurological deficit in the patient with fusiform aneurysm on lower basilar trunk.