• Journal of Korea Society of Industrial Information Systems
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• v.7 no.2
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• pp.74-81
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• 2002

In general, a multipath generator consists of a time delay generator, phase rotator, and amplitude attenuator, and is implemented mostly in an analog manner. Analog, or partially analog versions of a multipath generator is disadvantageous in that they may suffer from problems associated with component aging and adjustment, signal fidelity degradation stemming from repeated A/D and D/A conversion use of high frequency to achieve fine i.e., subsample fractional tin delays. This paper presents the design and implementation methodology of a full digital multipath generator which can be used in performance evaluations of digital terrestrial television as well as communications, receivers. In particular, an efficient practical method is proposed which can achieve both integer and fractional time delays simultaneously, without placing restrictions on the allowable system master clock frequency. The proposed algorithm lends itself to minimizing hardware implementation cost by relegating some fixed put of the computation involved to an IBM PC. The proposed multipath generator occupies only a single digital board space, and its experimental results are provided to corroborate the proposed implementation methodology.

• Journal of The Korean Association For Science Education
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• v.23 no.1
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• pp.75-85
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• 2003

We have developed of a criterion that would help to select and develop performance assessments in science education. There are six categories of a criterion: Fidelity, satisfaction, content validity, fairness & suitability, reliability & objectivity, and usability. There are the total of 25 sub-categories under the six categories. Five science educators evaluated the validity of the criterion. For reliability of the criterion, Kendall's tau-b was used. Eight science educators and elementary teachers evaluated three performance assessment tasks for the correspondence of the criterion. This study also discuss the implications of this criterion as well.

• Journal of Service Research and Studies
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• v.8 no.1
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• pp.1-12
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• 2018

The current research investigates an optimal design for the service system, which refers to the entire process of implementing, providing, and utilizing wisdom assets. We analyzed the intrinsic commonality of wisdom assets and services, and carried out research based on optimality in fidelity to service essence. The essential characteristics of service are horizontality, interactivity, harmonization, and relationship. It is suggested that the operating process can be implemented in the best condition when the wisdom asset service system is designed based on the four essential characteristics of services. It has been demonstrated that the entire process of production, delivery, marketing and quality control of wisdom contents can be designed on the basis of the essence of wisdom and service. After designing a basic service model, detailed service models are presented. The purpose of this study was to solve the problems of the material civilization society which is suffering mentally and to design the social service model which is high in productivity but mentally healthy. By supplementing and deepening the results of this study, it will be possible to develop and implement desirable social service model in which all societies live a happy life.

• Journal of Digital Convergence
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• v.14 no.3
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• pp.337-344
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• 2016

For the past half century, researches on human psychology have witnessed the flourish of various research tools in this area. Many psychological measures were developed to get objectified data and this trend has lead to the abundance of quantified results. However, considering subjectiveness and refinements of human experience, the research focused on individual's unique perspectives and explanations is needed also. In this vein, this study proposed the usefulness of photography as a research tool for human psychology. With the wide spread of smart phone, taking photo became the everyday activity for modern people and also a part of a public art. If photo could play an efficient and unique role to study human psychology, the depth and width of human understanding might change dramatically in positive way. Two friendship photos were presented to suggest the possibility of photo as a research tool and final considerations of using photo were suggested briefly.

• The Journal of Korean Association of Computer Education
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• v.6 no.4
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• pp.157-169
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• 2003

Teachers talked about the teaching and learning materials which were many but they were not always useful. Many teaching and learning materials called forth the quantitative expansion of them because of developing and delivering them after activating the education of using ICT. These results gave many teachers many advantages in comparison being in a difficult class because of few them. But, in spite of many good points, many teachers said that there were many materials but they were not useful and they could not find easily the fit material for themselves. These teacher's response based on the delivery method of teaching and learning materials is to be improved and the searching method of them is to be improved. To solve these problem, we proposed a method aobut the system for managing the quality of teaching and learning materials. It gives many teachers the advanced teaching and learning materials and the method for finding them more easy.

• Journal of the Korean Institute of Telematics and Electronics
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• v.10 no.1
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• pp.18-26
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• 1973

In AM detection system, when the ratio of the frequency of the carrier to that of the modulating signal becomes less than a ratio of approximately 10:1, AM detectors become unable to detect the impressed signal in a satisfactory waveform. The failure of detecting such a super wide-band AM signal resulting from charging and discharging transient phenomena in associated diode circuit during the detecting of AM signal, has been a cause of limiting the channel capacity in AM or FM super multiplexing systems. This Paper presents the "Poly-phase Envelope Detection System" as a suitable method to solve the problem and the analyses of the system suggested. This system will make it possible to take the envelope out of the impressed AM signal to any desired degree of accuracy even when the ratio of the frequency of the carrier to that of the modulating signal approaches unity. Experiments were carried out to verify the validity of the theory of Poly-phase Envelope Detection System by adopting the frequency conversion method from among the two proposals.proposals.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.1
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• pp.88-97
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• 1996

The metallization is the key to determining cell costs, cell performance, and system reliability. Screen printing technology suffers from several limitations affecting mainly the front grid. The buried contact solar cell (BCSC) was specifically desinged to be compatible with low cost, mass production techniques and avoid the conventional metallization problem. By using electroless plating technique, we performed this metallization inexpensively and reliably. This paper presents the details of the optimization procedure of metallization schemes on laser grooved cell surfaces. Commercially available Ni, Cu and Ag plating solutions were applied for the cell metallization. The application of those solutions on the buried contact front metallization has resulted in an cell efficiency of 18.8%. The cell parameters are an open circuit voltage of 651 mV, short circuit current density of 37.1 mA/$\textrm{cm}^2$, and fill factor of 77.8 %. The efficiency of over 18 % was achieved in the above 90% of the batch.

• Korea Journal of Hospital Management
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• v.15 no.1
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• pp.1-12
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• 2010

This study was tried to evaluate the level of completeness and the accordance in electronic medical records by comparing paper-based medical record in doctor's admission records, discharge summary, and nursing information records. Medical records of inpatients of neurology department that the 100 paper-based medical records in 2004 and 100 electronic medical records in 2006 were targeted. Existence of record items and doctor-nurse record accordance were evaluated in doctor's admission record, discharge summary, admission nursing information record, and discharge nursing information record. There were not any differences between electronic medical records and paper-based medical records in doctor's admission record and discharge summary. Electronic medical records had less missing records than paper-based medical records in admission and discharge nursing information records. Electronic medical records showed higher accordance than the paper-based medical record in doctor-nurse record generally, but there were statistically differences in only medication, allergy, smoking, and drinking (p<0.05). In this study, it was verified that the quality of electronic medical records are better than paper-based records in nursing information record and doctor-nurse record agreement.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.1
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• pp.13-21
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• 2020

Surrogate models have been used for the rapid estimation of six-DOF aerodynamic coefficients in the context of the design and control of a missile. For this end, we may generate highly accurate surrogate models with a multitude of aerodynamic data obtained from wind tunnel tests (WTTs); however, this approach is time-consuming and expensive. Thus, we aim to swiftly predict aerodynamic coefficients via co-Kriging using a few WTT data along with plenty of computational fluid dynamics (CFD) data. To demonstrate the excellence of co-Kriging models based on both WTT and CFD data, we first generated two surrogate models: co-Kriging models with CFD data and Kriging models without the CFD data. Afterwards, we carried out numerical validation and examined predictive trends to compare the two different surrogate models. As a result, we found that the co-Kriging models produced more accurate aerodynamic coefficients than the Kriging models thanks to the assistance of CFD data.

• Journal of Bio-Environment Control
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• v.6 no.1
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• pp.34-42
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• 1997

Effects of DIF on stem elongation in plug seedlings of mini tomato ‘Mini Carol’ and on the growth and flowering after transplanting were investigated. Stem elongation of seedlings was mainly influenced by day temperature rather than night temperature. When the effect of ＋DIF was compared to that of -DIF under the same average daily temperature(ADT), day temperature had greater impact on internode elongation than night temperature. On the other hand, leaf unfolding rate increased and compactness decreased as ADT in creased. Differences in internode length affected by DIF during seedlings stage DIF progressively diminished during growth period after transplanting. Node position at which first flower was initiated was lowered as ADT decreased. It was concluded that DIF treatment was an applicable tool for control of stem elongation, particularly to reduce stem length without a noticeably adverse effect on the growth and development of plant after transplanting.