• Asian Journal of Atmospheric Environment
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• v.2 no.1
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• pp.34-46
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• 2008

Emissions inputs for use in air quality modeling of Korea were generated with the emissions inventory data from the National Institute of Environmental Research (NIER), maintained under the Clean Air Policy Support System (CAPSS) database. Source Classification Codes (SCC) in the Korea emissions inventory were adapted to use with the U.S. EPA's Sparse Matrix Operator Kernel Emissions (SMOKE) by finding the best-matching SMOKE default SCCs for the chemical speciation and temporal allocation. A set of 19 surrogate spatial allocation factors for South Korea were developed utilizing the Multi-scale Integrated Modeling System (MIMS) Spatial Allocator and Korean GIS databases. The mobile and area source emissions data, after temporal allocation, show typical sinusoidal diurnal variations with high peaks during daytime, while point source emissions show weak diurnal variations. The model-ready emissions are speciated for the carbon bond version 4 (CB-4) chemical mechanism. Volatile organic carbon (VOC) emissions from painting related industries in area source category significantly contribute to TOL (Toluene) and XYL (Xylene) emissions. ETH (Ethylene) emissions are largely contributed from point industrial incineration facilities and various mobile sources. On the other hand, a large portion of OLE (Olefin) emissions are speciated from mobile sources in addition to those contributed by the polypropylene industry in point source. It was found that FORM (Formaldehyde) is mostly emitted from petroleum industry and heavy duty diesel vehicles. Chemical speciation of PM2.5 emissions shows that PEC (primary fine elemental carbon) and POA (primary fine organic aerosol) are the most abundant species from diesel and gasoline vehicles. To reduce uncertainties in processing the Korea emission inventory due to the mapping of Korean SCCs to those of U.S., it would be practical to develop and use domestic source profiles for the top 10 SCCs for area and point sources and top 5 SCCs for on-road mobile sources when VOC emissions from the sources are more than 90% of the total.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.3
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• pp.285-292
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• 2016

In this study, FE-BE direct coupling methods of 1D and 2D problems are considered for the pontoon-type floating structure and the difference of the modeling dimensions is investigated for the hydroelastic response. The modeling dimensions are defined as the 1D problem consisting 1D beam-2D fluid coupling and the 2D problem consisting 2D plate-3D fluid coupling with zero-draft assumption. For case studies, hydroelastic responses of the 1D Problem are compared to those of the 2D Problem for a wide range of aspect ratio and regular waves. It is shown that the effects of the elastic behavior are increased by decreasing the incident wavelength, whereas the effects of the rigid behavior are increased by increasing the incident wavelength. In 2D problem, the incident wave angle can be considered, and slightly more accurate results can be obtained, but the computational efficiency is lower. On the other hand, in 1D problem with plate-strip condition, the incident wave angle cannot be considered, but when the aspect ratio is large, the overall responses can be analyzed through a simplified model, and the computational efficiency can be improved.

• Convergence Security Journal
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• v.8 no.1
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• pp.101-108
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• 2008

This research focuses on the process improvement of port logistics by using Lean methodology. On the one hand, we firstly analyze the current situation and weakness of the processes in port logistics, and then re-design the current processes by the principles of Lean discipline. Based on the appropriately changed processes, the improvement scheme of port logistics will be figured out. On the other hand, we construct the port logistics system by implementing the improved processes. The port logistics' processes accomplished in steel company will be further assorted and identified. The relationship of wharves process, operational process, shipping process, construction process, quality process, and purchasing process are also defined. Every process has been improved by Lean Tools in order to analyze the value added or non-value added processes, to improve the service level, and to reduce the cycle time, inventory, changing time, re-working and waste. Based on above, the appropriate environment that is suitable to Lean process of port logistics will be established and the modeling that can help to implement the improvement scheme will be figured out.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1869-1872
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• 2003

As SLA(Sterealithography), SLS(Selective Laser Sintering), LOM(Laminated Object Manufacturing), FDM(Fused Deposition Modeling) etc. The FDM system the heart of a study and is developed by Stratasys co. ltd, in US., is small and cheap R.P. The material filament is heated until the material reaches a near-liquid state, it is pumped through a nozzle and become hand with a shape required, and this nozzle move pumping on the previously deposited material. Such FDM system that choice deposition type with X-Y plouter obtain in the thin continue layer by decreasing amount of extrusion or to central the injection amount when the head slow down at the corner, but in the process that fusion wax or resin become hand, deformation occur and it will affect the shape accuracy and the surface roughness. Such effect will depreciate quality and reliability of the product. Therefore, when the product made in actuality, the fundamental study on the basis geometry(surface, volume, line, angle) must be preceded and it have been research by many Free Form Fabrication. So, this basic object study purpose to obtain the fundamental geometry data and to enhance the surface roughness of the shape. And an operant can use the data for the progress of the surface roughness. This study research the estimation and application of the prototype surface roughness by adjustment the injection amount. And basie of this research, describe the pattern of prototype surface roughness and also used the result to estimate the surface of prototype.

• Journal of Electrical Engineering and Technology
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• v.13 no.3
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• pp.1069-1078
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• 2018

Demand response (DR) programs give opportunity to consumers to manage their electricity bills. Besides, distribution system operator (DSO) is interested in using DR programs to obtain technical and economic benefits for distribution network. Since small consumers have difficulties to individually take part in the electricity market, an entity named demand response provider (DRP) has been recently defined to aggregate the DR of small consumers. However, implementing DR programs face challenges to fairly allocate benefits and payments between DRP and DSO. This paper presents a procedure for modeling the interaction between DRP and DSO based on a bilevel programming model. Both DSO and DRP behave from their own viewpoint with different objective functions. On the one hand, DRP bids the potential of DR programs, which are load shifting and load curtailment, to maximize its expected profit and on the other hand, DSO purchases electric power from either the electricity market or DRP to supply its consumers by minimizing its overall cost. In the proposed bilevel programming approach, the upper level problem represents the DRP decisions, while the lower level problem represents the DSO behavior. The obtained bilevel programming problem (BPP) is converted into a single level optimizing problem using its Karush-Kuhn-Tucker (KKT) optimality conditions. Furthermore, point estimate method (PEM) is employed to model the uncertainties of the power demands and the electricity market prices. The efficiency of the presented model is verified through the case studies and analysis of the obtained results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.11
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• pp.2037-2042
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• 2017

The manufacturing facility is generally operated by a pre-set program under the existing factory automation system. On the other hand, the manufacturing facility must decide how to operate autonomously in Industry 4.0. Determining the operation mode of the production facility itself means, for example, that it detects the abnormality such as the deterioration of the facility at the shop-floor, prediction of the occurrence of the problem, detection of the defect of the product, In this paper, we propose a manufacturing process modeling using a queue for detection of manufacturing process abnormalities at the shop-floor, and detect abnormalities in the modeling using SVM, one of the machine learning techniques. The queue was used for M / D / 1 and the conveyor belt manufacturing system was modeled based on ${\mu}$, ${\lambda}$, and ${\rho}$. SVM was used to detect anomalous signs through changes in ${\rho}$.

• Korean Institute of Interior Design Journal
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• v.26 no.3
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• pp.45-54
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• 2017

A social phenomenon that occurs in a physical space is said to be a complex system. However, space syntax, which is commonly employed by researchers to identify such social phenomena, has various limitations in interpreting their complexity. On the other hand, agent-based modeling considers a variety of factors including the personality of the agent, objective-oriented work flows, estimation according to time flows and better prediction of space use through diverse parameters depending the situation, as well as the characteristics of the space. The agent-based method thus has the potentials to be developed as an alternative to space syntax techniques. In particular, discrete event driven simulation(DEVS), which is part of the agent-based modeling method, embraces the concept of networks just like space syntax, which allows a possible theoretical linkage in the future. This study suggests a procedural model of agent-based DEVS reflecting two different connection methods, i.e. connections between adjacent areas and those of the entire space, and attempts to identify the relationship between the local and regional indices of space syntax. A number of spaces were selected as examples-one for a preliminary experiment and eight modified for the main experiment-and space syntax and DEVS were applied to each of them. The comparative analysis of the results led to the conclusions as follows: 1) Adjacent connections were closely related to local indices, while the whole-space approach to regional indices. Local integration shows both characteristics. 2) Observation of the time flow model indicated a faster convergence with the range of 1 to 3-fold of the total time of one lap, with the error of less than 10%. 3) The heat map analysis showed more obvious characteristics of using the space for the entire space rather than adjacent connections. 4) Space syntax shows higher eligibility than ABM.

• Nutrition Research and Practice
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• v.14 no.2
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• pp.167-174
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• 2020

BACKGROUND/OBJECTIVES: With the advances in technologies, self-service kiosks at foodservice operations are becoming a new way of service provision. This study examined the relationships among the menu information quality, nutrition information quality, technology acceptance characteristics, and customer behavioral intention toward the kiosks in fast food restaurants. SUBJECTS/METHODS: A survey with a self-administered method was distributed online and offline. The sample consisted of customers who had used the kiosks at fast food restaurants in the last six months prior to the survey. The study hypotheses were tested by applying structural equation modeling. RESULTS: Structural equation modeling revealed the positive impacts of menu information quality and nutrition information quality, technology acceptance characteristics, and behavioral intention toward kiosks at fast food restaurants. On the other hand, one hypothesis (Hypothesis 4) on the impact of nutrition information quality on the perceived usefulness was rejected. CONCLUSION: The study is the first to investigate nutrition and menu information at foodservice kiosks and relate them to technology acceptance. The study is very timely and adequate in the time of the 4^th industrial revolution. The critical importance of the presentation of nutrition information and menu information at the kiosks at fast food restaurants was verified. The academic and industrial implications of the study findings were discussed.

• Fashion & Textile Research Journal
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• v.19 no.3
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• pp.312-319
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• 2017

The purpose of this study was to develop a customized wrist brace using 3D scanner and 3D printer. This study included in-depth interviews with people who had wrist pain and ever used wrist braces. The wrist brace has been designed and modeled by the CAD program after 3D scanning the wrist of subjects. Based on the results of the in-depth interviews on wrist brace users and design investigation in the market, a prototype of the wrist brace has been created. The wrist brace does not compress the hand and is easy to put on. In addition, it is adjustable to the wrist of users, allowing them to move his or her wrist without any restrictions. A computer-modeling program produced solid files for the design of the wrist brace after 3D scanning ten subjects' hands. It features a lattice-patterned surface, a velcro adjustment and trimming to smoothen the surface. PLA filaments were used to 3D print the wrist brace. As for the assessment, the wrist brace has been evaluated to be easy to put on and adjust to user's wrist. However, when it comes to appearance and comfortability, it was rated 3.0 or slightly above. This is because 3D printing materials are firm and not flexible compared to other materials such as neoprene or stretchable bands.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.2
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• pp.317-325
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• 2019

A suction caisson has been widely used for anchor and foundation of offshore structures due to its broad application, simple installation, and rapid construction. In design of suction caisson foundation, the bearing capacity and the stability of soil are mainly dealt with and analysis methods for them are presented in design codes related to the foundation. On the other hand, the method for structural safety analysis of the suction caisson is not generalized, in particular for load modeling of the caisson under suction. Consequently, there are difficulties in design of the caisson cross section. For this reason, this study analyzed the magnitude and distribution of pore water pressure on inner and outer surface of the caisson using theoretical and numerical seepage analyse, and an approach to reasonably estimate the load applied to the structural analysis of the caisson was presented. Furthermore, effects of penetration depth, anisotropy of permeability, and suction pressure on the pore water pressure were analyzed.