• 한국농공학회지
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• 제44권5호
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• pp.54-66
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• 2002

A grid-based hydrological model, CELTHYM, capable of estimating base flow and surface runoff using only readily available data, was used to assess hydrologic impacts caused by land use change on Little Eagle Creek (LEC) in Central Indiana. Using time periods when land use data are available, the model was calibrated with two years of observed stream flow data, 1983-1984, and verified by comparison of model predictions with observed stream flow data for 1972-1974 and 1990-1992. Stream flow data were separated into direct runoff and base flow using HYSEP (USGS) to estimate the impacts of urbanization on each hydrologic component. Analysis of the ratio between direct runoff and total runoff from simulation results, and the change in these ratios with land use change, shows that the ratio of direct runoff increases proportionally with increasing urban area. The ratio of direct runoff also varies with annual rainfall, with dry year ratios larger than those for wet years shows that urbanization might be more harmful during dry years than abundant rainfall years in terms of water yield and water quality management.

• 대한수학회보
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• 제54권2호
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• pp.687-704
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• 2017

Using a simple formula for conditional expectations over an analogue of Wiener space, we calculate a generalized analytic conditional Fourier-Feynman transform and convolution product of generalized cylinder functions which play important roles in Feynman integration theories and quantum mechanics. We then investigate their relationships, that is, the conditional Fourier-Feynman transform of the convolution product can be expressed in terms of the product of the conditional FourierFeynman transforms of each function. Finally we establish change of scale formulas for the generalized analytic conditional Fourier-Feynman transform and the conditional convolution product. In this evaluation formulas and change of scale formulas we use multivariate normal distributions so that the orthonormalization process of projection vectors which are essential to establish the conditional expectations, can be removed in the existing conditional Fourier-Feynman transforms, conditional convolution products and change of scale formulas.

• 한국의류학회지
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• 제17권1호
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• pp.137-149
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• 1993

The concept of style including the external form and internal meaning provides a useful structure to clarify the historical phenomenon on dress. The purpose of this study was to explore surrealism related to the external form and internal meaning and the stylistic change of surrealism through 1930 and 1988 according the linked solution proposed by Brodsky. The results were as follows; 1. In terms of double roots including the external form and the internal meaning on the surrealism of dress, first, the external form was founded to be that each objects having symbolic meaning was dislocated from its original place to dress. Second, the aspects of internal meaning intended to represent not rational and external world but irrational as well as to reveal other nature of object or dress itself. 2. The change of surrealistic style on dress was characterised as "linked solution" change theory than cyclical change theory through the historical data from 1930 to 1988 of documentary sources.

• 펄프종이기술
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• 제37권1호
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• pp.67-72
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• 2005

In the grade change operations inputs and outputs are highly correlated and application of conventional linear feedback control methods such as PID schemes might lead to poor control performance. In this study the neural networks model for the grade change operation is trained by using bilinear terms which can represent non-linear characteristics of grade change operations. The inverse model of the grade change operation is obtained from training and the optimal input variables are computed from the trained neural networks as well. The proposed bilinear inverse model predictive control scheme was found out to showlittle discrepancy between simulated outputs and setpoints.

• 설비공학논문집
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• 제12권2호
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• pp.189-199
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• 2000

This paper investigates the thermodynamic performance of latent heat thermal energy storage system using two phase change materials(2-PCM system). The thermodynamic merit of using 2-PCM is clear in terms of exergetic efficiency, which is substantially higher than that of 1-PCM system. Optimum phase change temperature to maximize the exergetic efficiency exists for each case. The heat transfer area ratio of high temperature storage unit, X, becomes another important parameter for 2-PCM system if the phase change temperatures of given materials are different from those of optimum conditions. It is a good approximation for X$_{opt}$ to be 0.5 when optimum phase change temperatures are used. Otherwise X$_{opt}$ is determined differently as a function of given phase change temperatures.res.

• East Asian mathematical journal
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• 제33권4호
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• pp.431-451
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• 2017

This is a descriptive study with the intent of providing a rich characterization of teachers' perceptions of rate of change. The nature of teachers' perceptions and differences among teachers were examined by collecting data through a survey on teachers' conceptions of rate of change in terms of learning goals, prerequisites, and beliefs about teaching and learning of rate of change, and an interview individually assessing teachers' concept images and definitions. The participating 13 teachers were selected to provide a range of similar and contrasting levels of experiences based on the teachers' educational background and the number of years they had been teaching. Findings and implications of this study are discussed.

• Nuclear Engineering and Technology
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• 제31권1호
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• pp.9-16
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• 1999

A 330 MWt-sized multi-purpose integral-type reactor, SMART is under development in Korea for the use of nuclear energy other than electricity generation. In this study, various radioactive source terms are estimated for SMART. SMART is different from conventional reactor concepts in operation and design. Therefore Specific Calculation method namely recurrence model is used. This model is based on the change rate in the RC radioactivity materials and operational characteristics of SMART Calculation results show tremendously increase of the levels of RC activity because no cleanup of RC and long term operation.

• 한국유기농업학회지
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• 제21권3호
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• pp.335-350
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• 2013

With the efforts to development of renewable energy technologies, and increasing awareness to environmental issues, the usage of wood pallets has been increasing every year since the introduction of wood pallet technology to the domestic market. until 2009, majority usage of pellet boiler was in the residential houses. In an effort to increase the distribution of wood pellet boiler to cultivation facilities with high usage of fuels, The Ministry of Agriculture and Forestry has launched a distribution project of wood pellet boiler for fuel usage as a part of the agricultural and fishery energy efficiency projects. Although only small number of farms with a heat-culturing facility have replaced from conventional boiler to pellet boiler. Although part of reason for low usage of pallet boiler is lack of understanding and information of it, the main reasons are high initial cost and uncertainty of its cost efficiency. Also, most people from agricultural industry don't realize it's significance in terms of environmental benefit due to lack of understanding in 'resource circulation' and 'adopting to climate change'. In this study, first, we did a cost-efficiency analysis of the farm which uses a diesel boiler to grow cucumber, tomato, paprika. Then we replaced the diesel boiler to a pallet boiler and measured its cost-efficiency again. By comparing the cost-efficiency of the diesel boiler with the pellet boiler, we analyzed the economic viability of pellet boiler. Then we analyzed viability of pallet boiler usage in terms of 'resource circulation' and 'adopting to climate change'. As a result of our analysis, we have found out that under the current system of government support, the energy usage varies depends of the types crops grown and the higher the energy use, the more cost efficient it is to use the pallet boiler. Also, it is economically viable to use the pallet boiler in terms of 'resource circulation' and 'adopting to climate change'.

• 복식
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• 제63권5호
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• pp.35-50
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• 2013

This thesis is based on the study of formativeness and versatility of Sarong. For the aim of the research, Sarongs were classified into two types: rectangular and tube, using its original form as the basis. These two types of Sarongs were divided into more detailed groups depending on the purposes of attire, such as skirts, dresses, and capes. To look into the formativeness and versatility of Sarong, the usage of wear and expression methods were observed based on these categories. The following results were found regarding the versatility of Sarong: First, Sarong has a wide degree of versatility in terms of usage. It can be worn as a skirt, a head scarf, a dress, a cape, or used as a carrier or even a sleeping bag, based on one's intention. The change of usage is often accompanied with the change of forms, as can be shown by the longyi of Myanmar, the tube type Sarong, which is used as briefs. Second, Sarong has a wide degree of versatility in terms of function. Variations of instrumental and expressive function of Sarong are observed simultaneously. The physical function sometimes coincides with the changes of usage as mentioned above. The way that Sarong's are expressed in different social situations changes depending on the wearer's social status, religion, or origin. So by looking at the way a Sarong is worn, others can tell if a person is going to social events such as festivals and weddings. Third, Sarong has a wide degree of versatility in terms of design. However, even if same usage and function is pursued, the design can be different based on an individual. This is because the external change of Sarong is affected by individuality or aesthetic sense of the wearer.

• 대한치과교정학회지
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• 제54권3호
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• pp.142-152
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• 2024

Objective: This retrospective cohort study aimed to assess and compare the accuracy of 3 different Invisalign^® treatment regimens in terms of variations of aligner change frequency and type of aligner material in achieving maxillary dental buccal expansion. Methods: Altogether, 120 adult patients whose treatment involved maxillary dental expansion with Invisalign^® were included. The patients were divided into 3 groups, with each group comprising 40 patients as follows: SmartTrack^® 1-week changes (ST1), SmartTrack^® 2-week changes (ST2), and EX30^® 2-week changes (EX2). The groups were assessed by comparing actual changes achieved with those prescribed by ClinCheck^®. The rates of clinically significant inaccuracies (CSI) observed for buccal expansion (≥ 0.5 mm) and buccolingual inclination (≥ 2°) during expansion were then determined. Results: In terms of expansion, the ST1 group demonstrated the highest CSI rate at all tooth levels, whereas the ST2 group had the lowest rate of CSI and the lowest mean inaccuracy for each tooth level. In terms of buccolingual inclination, the ST1 group had the highest CSI rate across all tooth levels, whereas the EX2 group had the lowest CSI rate at all tooth levels except for the canine level where the ST2 group had the lowest CSI rate. A tendency toward overexpression of buccal crown inclination, and underexpression of buccal expansion was observed at all tooth levels. Conclusions: Two-week aligner change regimens offer improved accuracy compared with 1-week aligner changes. SmartTrack^® 2-week changes were the most accurate for buccal expansion, whereas EX30^® 2-week changes were the most accurate for buccolingual inclination.