• 한국연소학회지
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• 제21권4호
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• pp.16-22
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• 2016

Pressure and temperature variations in a shock tube have been studied numerically by changing the diameter ratio of a driven part to a driver part. There are five cases where the adopted diameter ratios are 40%, 50%, 60%, 80%, and 100% respectively. The diameter of the driver part remains unchanged meanwhile the shock tube driven part diameter increases from 40% to 100% of the driver part. In the 100% ratio case, the driver part and driven parts have the same diameter of 66.9 mm. As the diameter ratio decreases, the pressure in the shock tube and available test time are increased.

• 한국초등과학교육학회지:초등과학교육
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• 제20권1호
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• pp.45-57
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• 2001

The purpose of this study is to guide and apply gettable and accessible materials around everyday life into classroom instruction, and to find out their effects on student academic achievement. In order to achieve it, this study was tried to develop and guide available materials around life in teaming activities, to provide a preliminary assignment that could apply the available materials, and to compare its academic achievement to one from field trip loaming. For the hypothesis testing, first, the experimental and comparing classes were selected based on the results of basic learning diagnostic evaluation, which conducted by the researcher being served as a full-time science teacher of the third and sixth grade of K elementary school in Kwangju for 2 years. Secondly, the instructional use of the available materials around life was applied to the experimental class. Also, the instructional use of the existing materials was applied to the comparing class. Finally, for the testing of the effects on academic achievement, the posterio test was implemented after conducting the experimental instruction in knowledge·understanding, inquiry process, and attitude domains classified by the unit characteristics. Using SPSS/WIN program the t-test was performed in order to compare the differences between the two groups. Major findings were as follows: 1) In the achievement test of knowledge·understanding domain, there were no significant differences at the 5％ level between the experimental and comparing classes. It could be difficult to say, therefore, that the instructional use of the available materials around life was more effective than the instructional use of the existing materials. However, it had some effects on differences between the third grade final achievement test and sixth grade experimental class. 2) In the achievement test of inquiry process domain, there were some significant differences in that the sixth grade experimental class was higher than the third grade out-of classroom experience unit. It was indicated that the instructional use of the available materials around life had some effects on improving the students' inquiry ability 3) In achievement test of attitude domain, there were some significant differences. It was shown that the self-evaluation test of the sixth grade experimental class unit was higher than that of the third grade out-of classroom experience unit; Especially, the learning activities in the experimental class were more active, and the experimental practice ability was improved. It was presented that the instructional use of the available materials around life had some effects on the students' academic achievement in attitude domain. It was concluded from this study that the instructional use of the available materials around life was less effective on Knowledge understanding domain, but was effective on improving their scientific inquiry ability and interest on science education.

• 한국임상약학회지
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• 제1권1호
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• pp.15-21
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• 1991

This study was attempted to investigate the dissolution rate and bioavailability of commercially available furosemide preparations. A. B. and C. The dissolution test was conducted in an artificial gastric juice using the basket method. and furosemide (40 mg) was administered orally to 8 normal volunteers by cross-over design. The results were as follows: the AUC and dissolution rate in 100 min ($D_{100\;min}$) were higher in order of preparations. A > C > B. But the peak concentration. time to reach peak concentration $(T_{max})$, and mean dissolution time (MDT) were in order of preparations. C > A > B. There were significantly linear correlations between the AUC and the $D_{100\;min}$, and between the $T_{max}$ and the MDT. From the results of this experiment. it can be concluded that commercially available preparations bioavailability of furosemide, which may be predicted from the dissolution rate.

• Journal of Biosystems Engineering
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• 제40권3호
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• pp.277-283
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• 2015

Background: Foodborne disease outbreaks from various food sources are a major health concern worldwide. Current methods for detection of foodborne pathogens are both expensive and time-consuming. Purpose: This review aims to present the current information available on the use of lateral flow test strips to detect pathogens in food products to enhance food safety. Results: Frequent foodborne disease outbreaks from various food sources have increased the need for rapid and easy methods for routine analysis of foodborne pathogens. Present detection methods for foodborne pathogens require expensive instruments, experts, and long time for sample analysis. Lateral flow test strips have drawn attention in recent years because of their ability to detect analytes quickly and easily. This review focuses on the principle of the lateral flow test, the various formats of lateral flow test strips, recognition elements, labeling tags, and reading instruments. In addition, this review also discusses the future prospects for the lateral flow test strips.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.13-17
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• 2003

Requirements of a benchmarking for rapid prototyping systems and process usually include manufacturing time, cost (including system price), and dimensional accuracy. This paper deals with a benchmarking comparisons to investigate the functional requirements of RP system. A special designed IMS_T2 test part with dimensional. geometrical, and surface roughness features has been used in the inspection of RP processes. IMS_T2 test part was built on 5 commercially available RP machines which are relatively new model in Korea.

• 한국의류학회지
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• 제29권9_10호
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• pp.1306-1315
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• 2005

Impulse buying has been considered a pervasive and distinctive phenomenon in the modern lifestyle and has been receiving increasing attention from consumer researchers and theorists. In the modern marketplace, spontaneous urges to buy and consume often compete with the practical necessity to delay the immediate gratification that purchasing provides. The purpose of this study is to conceptualize and test the framework of impulse buying behavior for fashion products using structural equation model. Data were obtained from 413 students attending universities during schedules classes in Busan. Analysis of the data, utilizing AMOS 4.1, supported most of the predictions. The results showed that situational variable(time available) and individual variable(fashion involvement) have direct effects on consumers' shopping emotions, including positive and negative emotion. Positive emotions had effects on all types of impulse buying(planned impulse buying, reminded impulse buying, and fashion-oriented impulse buying), while negative emotion affected two types of impulse buying(reminded impulse buying and fashion-oriented impulse buying). These emotional experiences influence impulse buying behaviors for fashion products serving as critical mediators. The findings suggest that time available and fashion involvement are good predictors mediated by shopping emotion to impulse buying behavior for fashion products. The implications of this research for future work on the shopping emotion and impulse buying behavior are discussed.

• 대한산업공학회지
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• 제33권1호
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• pp.76-85
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• 2007

A reliability acceptance sampling plan (RASP) consists of a set of life test procedures and rules for eitheraccepting or rejecting a collection of items based on the sampled lifetime data. Most of the existing RASPs areconcerned with the case where test items are available at the same time. However, as in the early stage ofproduct development, it may be difficult to secure test items at the same time. In such a case, it is inevitable toconduct a life test using sequentially supplied samples.In this paper, it is assumed that test items are sequentially supplied, the lifetimes of test items follow anexponential disthbution, failures are monitored continuously, arrival times of test items are known, and thenumber of test items at each arrival time is given. Under these assumptions, RASPs are developed by deter-mining the test completion time and the critical value for the maximum likelihood estimator of the mean lifetimesuch that the producer and consumer risks are satisfied. Then, the developed plans are compared to thetraditional Type-I censored RASPs in terms of the test completion time. Computational results indicate that thetest completion time of the developed RASP is shorter than that of the traditional Type-I censored plan in mostcases considered. It is also found that the superiority of the developed RASP becomes more prominent as theinter-arrival times of test items increase and/or the total number of test items gets larger.

• 한국군사과학기술학회지
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• 제18권5호
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• pp.566-573
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• 2015

The most important factor for the penetration performance of shaped charge is the liner design. By designing the liner to have properties of both high jet tip velocity and long jet break-up time, the better penetration performance could be acquired. Usually it is very difficult to satisfy above two conditions simultaneously. In this study, the liner with the shape of ogive was developed to have relatively larger jet mass compared to the conventional trumpet liner. The designed shaped charge showed jet properties with high jet tip velocity and long jet break-up time by using ogive liner and wave shaper. A commercially available hydro-dynamic code AUTODYN-2D was used for numerical analysis of jet formation. The flash X-ray test and the static penetration test were conducted to verify the results of numerical analysis.

• International Journal of Control, Automation, and Systems
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• 제5권4호
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• pp.410-418
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• 2007

For the purpose of fault detection of the primary control surface, real-time estimation of the longitudinal stability and control derivatives of the DURUMI-II using the flight data is considered in this paper. The DURUM-II, a research UAV developed by KARI, is designed to have split control surfaces for the redundancy and to guarantee safety during the fault mode flight test. For fault mode analysis, the right elevator was deliberately fixed to the specified deflection condition. This study also mentions how to implement the multi-step control input efficiently, and how to switch between the normal mode and the fault mode during the flight test. As a realtime parameter estimation technique, Fourier transform regression method was used and the estimated data was compared with the results of the analytical method and the other available method. The aerodynamic derivatives estimated from the normal mode flight data and the fault mode data are compared and the possibility to detect the elevator fault by monitoring the control derivative estimated in real time by the computer onboard was discussed.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제13권4호
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• pp.269-276
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• 2013

Information and communication technology (ICT) is a promising solution for mitigating road traffic congestion. ICT allows road users and vehicles to be managed based on real-time road status information. In Tanzania, traffic congestion causes losses of TZS 655 billion per year. The main objective of this study was to develop an optimal approach for integrating real-time road information (RRI) to mitigate traffic congestion. Our research survey focused on three cities that are highly affected by traffic congestion, i.e., Arusha, Mwanza, and Dar es Salaam. The results showed that ICT is not yet utilized fully to solve road traffic congestion. Thus, we established a possible approach for Tanzania based on an analysis of road traffic data provided by organizations responsible for road traffic management and road users. Furthermore, we evaluated the available road information management techniques to test their suitability for use in Tanzania. Using the floating car data technique, fuzzy logic was implemented for real-time traffic level detection and decision making. Based on this solution, we propose a RRI system architecture, which considers the effective utilization of readily available communication technology in Tanzania.