• Journal of The Korean Society of Agricultural Engineers
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• v.63 no.6
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• pp.61-75
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• 2021

This study aims to assess the changes in crop water requirement of paddy and upland according to future climate and land use changes scenarios. Changes in the spatiotemporal distribution of temperature and precipitation are factors that lower the stability of agricultural water supply, and predicting the changes in crop water requirement in consideration of climate change can prevent the waste of limited water resources. Meanwhile, due to the recent changes in the agricultural product consumption structure, the area of paddy and upland has been changing, and it is necessary to consider future land use changes in establishing an appropriate water use plan. Climate change scenarios were derived from the four GCMs of the CMIP6, and climate data were extracted under two future scenarios, namely SSP1-2.6 and SSP5-8.5. Future land use changes were predicted using the FLUS (Future Land Use Simulation) model. Crop water requirement in paddy was calculated as the sum of evapotranspiration and infiltration based on the water balance in a paddy field, and crop water requirement in upland was estimated as the evapotranspiration value by applying Penman-Monteith method. It was found that the crop water requirement for both paddy and upland increased as we go to the far future, and the degree of increase and variability by time showed different results for each GCM. The results derived from this study can be used as basic data to develop sustainable water resource management techniques considering future watershed environmental changes.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.397-400
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• 2000

This paper provides a product data representation, a data schema and related operations, for the management of engineering changes. The computer Interpretable format of the representation enables itself to be realized through databases and their applications to a component of a product data management system. Supporting general operations for the engineering changes, it resolves problems of the existing information systems in the nested engineering changes and the simultaneous change application to multiple products. To show the feasibility, a prototype system is implemented based on the representation.

• The Journal of Information Systems
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• v.18 no.1
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• pp.77-95
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• 2009

In customer-oriented make-to-order manufacturing environments, the works of BOM changes due to the changes of product specification and engineering are closely connected with almost all departments such as sales, engineering, production, procurement, cost, after service, etc within an enterprise. So, the contents of BOM changes must be instantly reflected on the related works among the departments. To effectively process these complex works of BOM changes, types of changes on product specification and engineering and types of BOM changes linked with those must be systematically defined, classified and managed by information systems. Thus, it is necessary to introduce solutions such as BPM and SOA in order to efficiently deal with complex business processes like BOM change management. This paper proposes a methodology of constructing information systems based on BPM and SOA. The proposed methodology defines the relationship between processes of BPM for definition, execution, monitoring, etc of business processes and services of SOA for connection among information systems within an enterprise, and presents a scheme of practically applying BPM and SOA solutions to actual business works. To show an utilization of the proposed methodology, the prototype system for product BOM management is implemented in order to efficiently deal with the works of BOM changes due to the changes of product specification and engineering.

• Journal of Ocean Engineering and Technology
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• v.20 no.6 s.73
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• pp.54-60
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• 2006

This study discusses characteristic of spatiotemporal changes of the sand barrier in the Nakdong estuarine for the last century, focusing on geomarphologic evolution and mobility of sand barriers in the view of coastal engineering. The Nakdong estuarine, the research subject, has a complexly changing natural environment by interaction between ground and marine elements such as ocean wave, tidal current, sediment, etc. Moreover, recently, unnatural geomorphologic changes (e.g., seaside reclamation, new harbor construction, etc.) has been radically increased in this area with increasing desire for coastal development. Because of this, its sand barrier has developed quite unstable condition. Therefore, to identify the development process of geomorphologic changes in this area, required is a close examination on historical characteristics of spatiotemporal changes of the sand barrier in relation to surrounding seaside reclamation and physical environmental changes. This study, based on the marine charts published in between 1927 and 1995 year, analyzes the length and area of the sand barrier for the last hundred years, and investigates the cause of the changes by looking into the change of water depth for the last two years and doing ocean-physical site observations. In conclusion, the sand barrier of the Nakdong estuarine expands toward the open sea by $7.4{\sim}26m$ in annual average, maintaining a fixed distance of $1,241{\sim}1.279m$, and its area is expected to increase about $2.8km^2$ annually. This is characterized by the wocean wave from the open sea and the discharge of Nakdong River.

• Journal of Biosystems Engineering
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• v.37 no.5
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• pp.327-334
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• 2012

Purpose: The color changes in red pepper during far infrared drying were studied in order to establish a color change model. Methods: The far infrared drying experiments of red pepper were conducted at two temperature levels of 60, $70^{\circ}C$ and two air velocity levels of 0.6 and 0.8 m/s. The results were compared with the hot-air drying method. The surface color changes parameters of red pepper were measured qualitatively based on L (lightness), a (redness), b (yellowness) and total color changes (${\Delta}E$). The goodness of fit of model was estimated using the coefficient of determination ($R^2$), the root mean square error (RMSE), the mean relative percent error (P) and the reduced chi-square (${\chi}^2$). Results: The results show that an increase in drying temperature and air velocity resulted in a decrease in drying time, the values of L (lightness) and a (redness) decreased with drying time during far infrared drying. The developed model showed higher $R^2$ values and lower RMSE, P and ${\chi}^2$ values. Conclusions: The model in this study could be beneficial to describe the color changes of red pepper by far infrared drying.

• International Journal of High-Rise Buildings
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• v.12 no.4
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• pp.351-362
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• 2023

In modern society, rapid environmental changes are occurring due to the complex interaction of various factors. Starting in 2020, the social environment is changing rapidly due to the impact of the pandemic, and the social and economic living environment is changing significantly not only in Korea but also internationally. In this trend, behavioral and spatial changes are occurring in response to changes in the architectural living environment. To analyze changes in behavior and space from an architectural perspective in response to changes in the social environment, first organize the concept and aspects of the pandemic that caused the change, examine the theory of the pandemic, and examine architectural responses to changes in the social environment. There is a need to analyze. Therefore, in order to architecturally review changes in the social environment due to the pandemic, the purpose of this study is to analyze the living behavior and space of major highrise residential complexes in the living environment and present new spatial alternatives in response.

• Journal of the Korean Society for Heat Treatment
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• v.5 no.3
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• pp.157-164
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• 1992

Barkhausen noise (BN) is created by the abrupt changes in the magnetization of materials under applied AC magnetizing field. These changes are known to be sensitive to residual and applied stresses. In this study, BN theory was reviewed and it was examined how BN intensity was affected by simultaneous stress, hardness and microstructural changes. Also, magnetoelastic effect was used to evaluate residual stresses through carrying out the cantilever beam test. An increase in BN intensity was observed when applied and residual stress changes from compression into tension. Microstructural softening by tempering also increased the amount of BN. Therefore, the quantitative evaluation of residual stress and microstructural changes will be possible, provided BN method is more studied about various materials through comparing with different stress measuring techniques.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.5
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• pp.718-723
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• 2016

The temperature changes are very important in improving the accuracy of the load forecasting during the summer. It is because the cooling load in summer contribute to the increasing of the load. This paper proposes a weekend load forecasting algorithm using the temperature change characteristic in a summer of Jeju. The days before and after weekends in Jeju, when the load curves are quite different from those of normal weekdays. The temperature change characteristic are obtained by using weekends peak load and high temperature data. And load forecasted based on the sensitivity between unit temperature changes and load variations. Load forecast data with better accuracy are obtained by using the proposed temperature changes than by using the ordinary daily peak load forecasting. The method can be used to reduce the error rate of load forecast.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.4
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• pp.174-179
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• 2022

Companies are making design changes by improving product quality and function to succeed while meeting customer requirements continuously. Design changes are changing the product BOM's amount, item, specification, and shape while causing a change in the product's structure. At this time, the problem of inventory exhaustion of parts before design change is a big topic. If the inventory exhaustion fails, the pieces before the design change become unused and are discarded, resulting in a decrease in asset value, and the quality cost of the design change affects the company's profits. Therefore, it is necessary to decide to minimize quality costs while minimizing waste inventory costs at the time of application of design changes. According to the analysis, priorities should be prioritized according to urgency because the quantity of items before the design change affects the applied lead time.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.49-49
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• 2016

The impact of land cover changes on streamflow of the Akaki catchment will be assessed using Soil and Water Assessment Tool (SWAT) model. The study will analyze the historical land cover changes (1993 to 2016) that have taken place in the catchment and its effect on the streamflow of the study area. Arc GIS will be used to analysis the satellite images obtained from the United States Geological Survey (USGS). To investigate the impact of land cover change on streamflow the model set up will be done using readily available spatial and temporal data, and calibrated against measured discharge. Two third of the data will be used for model calibration (1993?2000) and the remaining one-third for model validation (2001?2004). Model performance will be evaluated by using Nash and Sutcliff efficiency (NS) and coefficient of determination (R2). The calibrated model will be used to assess two land cover change (2002 and 2016) scenarios and its likely impacts of land use changes on the runoff will be quantified. The evaluation of the model response to these changes on streamflow will be presented properly. The study will contribute a lot to understand land use and land cover change on streamflow. This enhances the ability of stakeholder to implement sound policies to minimize undesirable future impacts and management alternatives which have a significant role in future flood control of the study area.