• Magazine of the Korean Society of Agricultural Engineers
• /
• v.30 no.1
• /
• pp.50-62
• /
• 1988

This study refers to the development of a hydrologic model simulating daily inflow and release rates for irrigation reservoirs. A daily - based model is needed for adequate operation of an irrigation reservoir sufficing the water demand for paddy fields which is closely related to meteorological conditions. Inflow rates to a reservoir need to be accurately described, which may be simulated using a hydrologic model from daily rainfall data. And the objective of this paper is to develop, test, and apply a hydrologic model for daily runoff simmulation. A well - known tank model was selected and modified to simulate daily inflow rates. The model parameters were calibrated using observed runoff data from twelve watersheds, Relationships between the parameters and the watershed characteristics were derived by a multiple regression analysis. The simulation results were in agreement with the data. The inflow model was found to simulate low flow conditions more accurately than high flow conditions, which may be adequate for water resources utilization.

• Journal of Korean Society of Rural Planning
• /
• v.2 no.2
• /
• pp.57-66
• /
• 1996

The purpose of this study is to suggest the rural village model which is able to be applied to the rural village (re)development. The rural village model consists of five sector models land use model, residential unit model, public facilities allocation model, productive space arrangement model, road & green system model. The village model as a spatial structure needs modification/revision through the its application to various sites. The following are suggestions developed in the process of preparing a model for the Korean rural village. First, some indices presented in the land use model need to be further studied as the planning indices before implementing the rural village projects. Second, it is recomended that the image of a rural village needs to be created by developing the residential unit(6 households) as a planning development unit, And various residential unit models need to be suggested. Third, it is desirable to develop the double circulation system and green edge(1 m), and to introduce pedestrian road as much as possible for the amenity of the residential environment, Fourth, being located within walking distance from the existing village, new-introduced site should be developed as a interlinked and opened structure. The rural village model is useful in preparing the spatial structure for the village (re)development, and in finding the best design solution responsive to the conditions of a project site.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.29 no.10
• /
• pp.515-529
• /
• 2017

EnergyPlus, which is widely used in various fields, provides Simple Window Model, a window model that can be used practically. However, the results of building load using the model are different from those of the standard model. The main cause of the deviation by Simple Window Model was analyzed to be due to the assumption that all windows were considered as single layer. The purpose of this study is to propose a window model that improves the cause of deviation by Simple Window Model and can be easily calculated from the algebraic relations. The proposed window model solved the heat balance equation algebraically by using seven window characteristic coefficients. The coefficient relationships consisted of the heat transmission coefficient and solar heat gain coefficient as input parameters make practical use and calculation possible. As a result of comparing the deviation between each window model by implementing the dynamic analysis method, the proposed window model showed that the deviation of the total heating/cooling energy consumption was reduced to 1/3 compared to Simple Window Model for one year. Although the maximum energy consumption did not show any significant improvement, the indoor temperature evaluation showed significantly reduced deviation.

• Korean Journal of Agricultural Science
• /
• v.49 no.4
• /
• pp.1001-1013
• /
• 2022

The purpose of this study is to build an oyster outlook model. In particular, by limiting oyster items, it was designed as a partial equilibrium model based on a panel analysis of a fixed effect model on aquaculture facilities. The model was built with a dynamic ecological equation (DEEM) system that considers aquaculture and harvesting processes. As a result of the estimation of the initial aquaculture facilities based on the panel analysis, the elasticity of the remaining facility volume in the previous month was estimated to be 0.63. According to Nerlove's model, the adjustment coefficient was interpreted as 0.31 and the adjustment speed was analyzed to be very slow. Also, the relative income coefficient was estimated to be 2.41. In terms of elasticity, it was estimated as 0.08% in Gyeongnam, 0.32% in Jeonnam, and 1.98% in other regions. It was analyzed that the elasticity of relative income was accordingly higher in non-main production area. In case of the estimation of the monthly harvest facility volume, the elasticity of the remaining facility volume in the previous month was estimated as 0.53, and the elasticity of the farm-gate price was estimated as 0.23. Both fresh and chilled and frozen oysters' exports were estimated to be sensitive to fluctuations in domestic prices and exchange rates, while Japanese wholesale prices were estimated to be relatively low in sensitivity, especially to the exchange rate with Japan. In estimating the farm-gate price, the price elasticity coefficient of monthly production was estimated to be inelastic at 0.25.

• Journal of the Korea Safety Management & Science
• /
• v.25 no.3
• /
• pp.9-15
• /
• 2023

As the first step of risk management, risk identification is inevitable to understand the degree of work safety. However, the safety requirements can be divided in necessary factors and additional factors. Thus, we propose a safety requirements assessment model using Kano model derived from Herzberg's two-factor theory, classifying safety requirements into ideal elements and must-be elements. The Kano model is usually applied to evaluate customer satisfaction divided into three major requirements in the fields of product development and marketing: attractive, must-be, and one-dimensional requirements. Among them, attractive requirement and must-be requirement are matched with ideal element and must-be element for safety requirement classification, respectively. The ideal element is defined as preventive safety elements to make systems more safe and the must-be element is referred to as fatal elements to be essentially eliminated in systems. Also, coefficients of safety measurement and safety prevention are developed to classify different class of safety requirements. The positioning map is finally visualized in terms of both coefficients to compare the different features. Consequently, the proposed model enables safety managers to make a decision between safety measurement and prevention.

• International conference on construction engineering and project management
• /
• 2009.05a
• /
• pp.847-855
• /
• 2009

While many studies on feasibility analysis for housing projects have been released, the main focus was on economic feasibility and factors related to developers were not clearly identified enough to be used in practice. In order to establish a feasibility analysis model for apartment development projects requested by developers in Korea, 31 driving factors behind projects' success were identified under seven different categories. Criterions of the each factor were also developed, and weight of each factor was assigned by applying the Analytical Hierarchy Process(AHP). Finally, based on the Monte Carlo simulation, the feasibility analysis model was established, providing probability distribution of project's grade. The model was applied to 12 housing projects to verify its reliability, and found that the model properly filtered projects that are unlikely to be profitable, indicating reasonable reliability of the model. The model can be a useful tool for contractors, especially with less experience in analyzing project development feasibility.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2006.04a
• /
• pp.395-402
• /
• 2006

In analyzing the nano-scale phenomena or behaviors of nano devices or materials, it is often desirable to deal with more atoms than can be treated only with a full atomistic simulation. However, even now, it is advisable to apply the atomistic simulation to the narrow region where the deformation field changes rapidly but to apply the conventional continuum model to the region far from that region. This equivalent continuum model can be formulated by applying the Cauchy-Born rule to the exact atomistic potential as in the quasicontinuum method. To couple the atomistic model with the equivalent continuum model, continuum displacements are conformed to the molecular displacements at the discrete positions of the atoms within the bridging domain. To satisfy the coupling constraints, we apply the Lagrange multiplier method. The continuum model in the bridging model should be applied on the region where the deformation field changes gradually. Then we can make the nodal spacing in the continuum model be much larger than the atomic spacing. In the first step, we generate the atomic-resolution mesh with the nodal spacing equal to the atomic spacing, and then we eliminate the nodal degrees of freedom adaptively using the node deactivation techniques. We eliminate more DOFs as the regions are more far from the atomistic region. Computing time and computational resources can be greatly reduced by the present node deactivation technique in multi scale analysis.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2022.05a
• /
• pp.152-152
• /
• 2022

Only employing historical data limits the estimation of the full distribution of probable Tropical Cyclone (TC) risk due to the insufficiency of samples. Addressing this limitation, this study introduces a semi-physical TC rainfall model that produces spatially and temporally resolved TC rainfall data to improve TC risk assessments. The model combines a statistical-based track model based on the Markov renewal process to produce synthetic TC tracks, with a physics-based model that considers the interaction between TC and the atmospheric environment to estimate TC rainfall. The simulated data from the combined model are then fitted to a probability distribution function to compute the spatially heterogeneous risk brought by landfalling TCs. The methodology is employed in South Korea as a case study to be able to implement a country-scale-based vulnerability inspection from damaging TC impacts. Results show that the proposed model can produce TC tracks that do not only follow the spatial distribution of past TCs but also reveal new paths that could be utilized to consider events outside of what has been historically observed. The model is also found to be suitable for properly estimating the total rainfall induced by landfalling TCs across various points of interest within the study area. The simulated TC rainfall data enable us to reliably estimate extreme rainfall from higher return periods that are often overlooked when only the historical data is employed. In addition, the model can properly describe the distribution of rainfall extremes that show a heterogeneous pattern throughout the study area and that vary per return period. Overall, results show that the proposed approach can be a valuable tool in providing sufficient TC rainfall samples that could be an aid in improving TC risk assessment.

• Korean Journal of Computational Design and Engineering
• /
• v.16 no.4
• /
• pp.305-313
• /
• 2011

This paper proposes a method for reusing kinematic design data for virtual facilities, Making a virtual model of a facility involves two major activities: geometric design (virtual model visualization) and kinematic design that should be remodeled frequently whenever design changes occur, Conventionally, a virtual model of an automated facility focuses on the design level, which mainly deals with design verification, alternative comparison, and geometric model diagnosis, Although a design level model can be designed with the information of past models from PLM system, a simulation level model is not sufficient utilized to be reused for kinematic design purpose, We propose a method for reusing kinematic information of a past simulation model to cope with this problem, We use the concept or the 'center of mass', which is a point representing the mean position of the matter in a body or system. And we also use comparison method of a boundary box to identity which 3D objects have to be involved from the design model to a link structure that is contained in the simulation model. Because a proposed method only use not a historical approach but a geometrical approach, it is more effective to apply to the field.

• KIEAE Journal
• /
• v.6 no.4
• /
• pp.25-32
• /
• 2006

Mock-up model can be applied to measure accurate performance data but difficult to apply the variables in experiment. There can be a slight experiment errors in Scale model, but various parameters can be applied for a objective experiment. This paper aims to compare the daylighting performance in 1, 1/5, 1/10 scale model of offices and analyze the experiment errors to certificate the influence of model experiment. To analyse daylighting performance, a comparison of a Mock-up model, sized $12.0m(w){\times}7.2m(l){\times}3.7m(h)$, designed for experimentation of daylighting systems and its 1:5, 1:10 scale model. It has an identical configuration of reference room and the test room. For the test room, the lightshelf system was designed as Micro-4 reflective material. To assess work plane illuminance and light factor, photometric sensors of each room were installed at work-plane(6 points) and exterior horizontal illuminance (1 point). And luminance of window, rare of the room was measured under clear sky. It is to be monitored by Agilent data logger, photometric sensor Li-cor and the Radiant Imaging ProMetric 1400. Comparisons with a light factor, increase-decrease ratio and luminance are discussed.