• Journal of the Korean Home Economics Association
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• v.36 no.3
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• pp.77-86
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• 1998

The aims of this study show the purpose of writing[Ka-ryae] and its transmission and operation from the end of Koryo to Chosun dynasty. And Studying of a traditional marriage ceremony as shown in [Ka-ryae], We intend to find a mental meaning and value in it. The major findings this study are as follows. 1. Though [Ka-ryae] was written by Chu-Ja who lived in the period of South-Song of China, it had greatly influenced the thought, system and life of Korean society from the end of Koryo to Chosun dynasty. 2. Studying the content of [Ka-ryae], we learned the respect, discretion and reghtness as the mental meaning and value of a marriage ceremony.

• Journal of Educational Research in Mathematics
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• v.27 no.4
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• pp.765-789
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• 2017

Arithmetic is the basis of school mathematics and in fact, number and operation in elementary school curriculum is the most basic and essential domain. Even though there has been a consensus that arithmetic should be taught more meaningfully beyond the emphasis of calculation skills and teachers should emphasize the aspect of the arithmetical thinking, it is difficult to find studies which focus on the arithmetical thinking itself. So this research aims to explore the meaning of the arithmetical thinking and extract the arithmetical thinking factors. In order to solve the research problems, we reviewed and analyzed the literatures and then conducted Delphi survey to extract arithmetical thinking factors. From the results of this research, we found the meaning of arithmetical thinking and the arithmetical thinking factors. Especially, the arithmetical thinking consists of 18 factors. It is important to pay attention to students' arithmetical thinking because there are various factors of the arithmetical thinking. It is necessary to identify the aspects of arithmetical thinking reflected in school mathematics based on the meaning of arithmetical thinking and its factors. Based on this, it is possible to find effective teaching and learning methods of arithmetic focusing on the arithmetical thinking.

• Computers and Concrete
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• v.6 no.3
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• pp.203-223
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• 2009

Regression analysis (RA) can establish an explicit formula to predict the strength of High-Performance Concrete (HPC); however, the accuracy of the formula is poor. Back-Propagation Networks (BPNs) can establish a highly accurate model to predict the strength of HPC, but cannot generate an explicit formula. Genetic Operation Trees (GOTs) can establish an explicit formula to predict the strength of HPC that achieves a level of accuracy in between the two aforementioned approaches. Although GOT can produce an explicit formula but the formula is often too complicated so that unable to explain the substantial meaning of the formula. This study developed a Backward Pruning Technique (BPT) to simplify the complexity of GOT formula by replacing each variable of the tip node of operation tree with the median of the variable in the training dataset belonging to the node, and then pruning the node with the most accurate test dataset. Such pruning reduces formula complexity while maintaining the accuracy. 404 experimental datasets were used to compare accuracy and complexity of three model building techniques, RA, BPN and GOT. Results show that the pruned GOT can generate simple and accurate formula for predicting the strength of HPC.

• KIEAE Journal
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• v.14 no.6
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• pp.105-110
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• 2014

The basic factors determining the amount of energy used in hospital buildings are weather conditions and building factors. But the real energy consumer is central plant equipment such as boilers and chillers that produce thermal energy for heating and cooling. Inaccurate decision of the primary equipment's size can cause a high initial-cost, an excessive equipment space, a wasted energy by low operation-efficiency and shortening of the machine's life. In this reason, the decision of optimal size for central plant equipment is very important. There are several factors for the decision such as an operation factor, a factor (equipment factor), piping losses and a simultaneous usage factor applied in the sizing process except a basic cooling load. But there is no standard method for applying those factors. Usually, factors are applied individually by an experience or custom of each engineer. In this study, the authors emphasize the meaning and the problem of those factors, examine them by analyzing factors which were applied to actual practices, and propose the recommendation value of safety, load, operation factors and application methods.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1326-1329
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• 1997

In designing the controller by changing the weighting matrix for the pirpose of satisfying constraints, the physical meaning of weighting matrix may disapperar and the system may not yield best performance because operation condition such as periodic disturbance was not considered. In this paper, the weighting matrix is fixed and controller is designed to minimize the new performance index to reduce the effects of periodic-type disturbances. This method is applied to design the satellite controller to verify the effetiveness.

• 전기의세계
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• v.29 no.11
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• pp.693-698
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• 1980

We T.E.C. have commenced to develop the O.F. cable in April, 1977. Now we have finished the Type-Test and produced in full-operation of 154KV 1x600mm$^{2}$ and 154KV 1x1200mm$^{2}$ O.F. cables. Especially we have completed pulling and splicing of the 24.82kms O.F. cable in KaeBong-OuRyu Route, and now it is operating well. This has important meaning that Extra High Voltage Under Ground Transmission Line has constructed by domastic engineers for the first time in Korea. Thank to arrange and publish it, and hope it can be helpful to the related.

• Journal of the Ergonomics Society of Korea
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• v.27 no.4
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• pp.109-117
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• 2008

Compared to the existing PC which uses a mouse and a keyboard, the touchscreen-based portable PC allows the user to use fingers, requiring new operation methods. However, current touchscreen-based web browser operations in many cases involve merely having fingers move simply like a mouse and click, or not corresponding well to the user's sensitivity and the structure of one's index finger, making itself difficult to be used during walking. Therefore, the goal of this study is to develop finger gestures which facilitate the interaction between the interface and the user, and make the operation easier. First, based on the frequency of usage in the web browser and preference, top eight functions were extracted. Then, the users' structural knowledge was visualized through sketch maps, and the finger gestures which were applicable in touchscreens were derived through the Meaning in Mediated Action method. For the front/back page, and up/down scroll functions, directional gestures were derived, and for the window closure, refresh, home and print functions, letter-type and icon-type gestures were drawn. A validation experiment was performed to compare the performance between existing operation methods and the proposed one in terms of execution time, error rate, and preference, and as a result, directional gestures and letter-type gestures showed better performance than the existing methods. These results suggest that not only during the operation of touchscreen-based web browser in portable PC but also during the operation of telematics-related functions in automobile, PDA and so on, the new gestures can be used to make operation easier and faster.

• Korean Journal of Computational Design and Engineering
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• v.4 no.3
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• pp.247-258
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• 1999

With the contemporary CAD/CAM system, where the tool path is generated and verified purely based on the geometric operation, geometric accuracy of the machined surface cannot be guaranteed dut to the cutting mechanics, meaning that the cutting mechanics should be incorporated in some fashion. In this paper, we incorporate the instantaneous cutting force and the tool deflection phenomena in predicting the machined surface for the finish-cut and milling operation. For the given NC dat including cutting conditions, the developed algorithm computes cutting force and deflection amount along the tool trajectory, and outputs the 3D graphic model of the machined surface together with error analysis. The validity and accuracy of the presented method has been tested by the actual cutting experiments. Experimental results and accuracy enhancement method together with implementing architecture of the VMCS (Virtual Machining CAM System) are discussed in the paper.

• 한국컴퓨터산업교육학회:학술대회논문집
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• 2003.11a
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• pp.33-38
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• 2003

Reports have a significant meaning in time-constrained large transaction environments, such as airplane control systems or wargame simulations. This is due to the necessity of generating reports within a limited scope of time without restraining the operation performance of large transaction environments. In order to generate reports in large transaction environments while satisfying time - constrained requirements, this paper propose a model which combines the incremental operation mechanism and materialized view mechanism using triggers and stored procedures. Further, the implementation and evaluation of the preposed model provides analysis for model characteristics.

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.2-3
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• 2001

Characteristics of two-dimensional slab photonic crystal lasers will be summarized. Room temperature c.w operation is demonstrated at 1.6 $\mu\textrm{m}$ by using InGaAsP slab-waveguide triangular photonic crystal on top of wet-oxidized aluminum oxide. Recently, 2-D PBG structures have attracted a great deal of attention due to their simplicity in fabrication and theoretical study as compared to the three-dimensional counterparts [1]. Air-guided 2-D slab PBG lasers were reported by Caltech group (2). However, this air-slab structure is mechanically fragile and thermally unforgiving. Therefore, a new structure that can remove this thermal limitation is dearly sought after for 2-D PBG laser to have practical meaning. In this talk, we report room-temperature continuous operation of 2-D photonic bandgap lasers that are thermally and mechanically stable.(omitted)