• Journal of Ocean Engineering and Technology
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• v.33 no.4
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• pp.358-363
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• 2019

The acoustic power is used as a primary index characterizing underwater sound sources and could be defined by its source level. The source level has been assessed using various experimental techniques such as the reverberation time method and reverberant tank plot method. While the reverberation time method requires reverberation time data extracted in a preliminary experiment in a reverberant water tank, the reverberant tank plot method only needs acoustic pressure data directly obtained at the reverberation water tank. In this research, these experimental techniques were studied in comparative experiments to estimate the source levels of underwater sources in a reverberant water tank. This paper summarizes the basic theories and procedures of these experimental techniques and presents the experimental results for an underwater source in a long cuboid water tank using each technique, along with a discussion.

• English Language & Literature Teaching
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• v.13 no.1
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• pp.181-210
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• 2007

This study is to suggest systematic and effective reading comprehension techniques or strategies to be used in EFL reading classes. According to the definition of reading and reading process, six essential elements of reading comprehension are categorized: 1) reading speed; 2) skimming and scanning; 3) logical organization; 4) pleasure reading; 5) vocabulary; 6) cultural background and world knowledge. To present a more effective teaching and learning approach to EFL reading comprehension than ever, an experiment was performed. The hypothesis of the experimental study was that there would be a difference in students' reading speed as well as reading comprehension and vocabulary between an experimental group and a control group depending upon the teaching approaches (experimental vs. traditional). The result of the study indicates that the experimental teaching approach which intensifies speed reading and pleasure reading techniques as well as 4 other essential techniques of reading comprehension is more effective than the traditional one in teaching and learning reading comprehension.

• International Journal of Concrete Structures and Materials
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• v.10 no.2
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• pp.189-203
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• 2016

This paper investigates on the use of advanced optical measurement methods, i.e. 3D coordinate measurement machines (3D CMM) and stereo-vision digital image correlation (3D DIC), for the mechanical analysis of shear deficient prestressed concrete members. Firstly, the experimental program is elaborated. Secondly, the working principle, experimental setup and corresponding accuracy and precision of the considered optical measurement techniques are reported. A novel way to apply synthesised strain sensor patterns for DIC is introduced. Thirdly, the experimental results are reported and an analysis is made of the structural behaviour based on the gathered experimental data. Both techniques yielded useful and complete data in comparison to traditional mechanical measurement techniques and allowed for the assessment of the mechanical behaviour of the reported test specimens. The identified structural behaviour presented in this paper can be used to optimize design procedure for shear-critical structural concrete members.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.11
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• pp.1424-1431
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• 2004

With traditional experimental methods such as the secondary fluid (e.g., water) calorimetric method, it is very difficult to accurately test the local condensation heat transfer inside mini-channels. Hence, there are large discrepancies between the results of previous studies. The experimental methods as well as unidentified sources of uncertainties could be reasons for such discrepancies. In this study, innovative experimental techniques were developed to measure the in-tube condensation heat transfer coefficient. With these techniques, very low heat dissipation rates such as several watts from the mini-channel could be estimated and low mass flow rates below the 0.1 ㎏/h could be measured with reasonable uncertainties. To the authors' knowledge, these techniques provide a unique experimental apparatus for measuring the condensation heat transfer coefficients inside the sub-millimeter hydraulic diameter single channels.

• BMB Reports
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• v.50 no.12
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• pp.610-614
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• 2017

Scientists planning research that involves the use of animals are required to examine the possibilities for replacement, reduction, or refinement (the Three Rs), and their protocol must be reviewed by the Institutional Animal Care and Use Committee. Good scientific practice involving appropriate search techniques on the available Three Rs resources is essential for both ethical and scientific reasons. Appropriate experimental design and statistical analysis techniques are particularly necessary for research involving the use of animals, because this can improve animal welfare and scientific outcomes, as well as saving animal lives. There are a number of resources to help researchers improve their search techniques, experimental design strategies, and their reporting of research involving the use of animals. However, there is little specific information or resources on the Three Rs alternatives that is readily available in the Korean language. This paper outlines the common errors made by submitting researchers that have been repeatedly observed during the ethical review of experimental protocols over the last ten years, and provides information on the Korean resources available to promote good scientific practice. This could help to bridge the gap between Korean scientists and animal welfare advocates assisting scientists to improve ethical considerations and conduct responsible research.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.1
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• pp.45-50
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• 2001

With increasing complexity of digital logic circuits, fast and accurate verification of functional behaviour becomes most critical bottleneck in meeting time-to-market requirement. This paper presents several techniques for accelerating a cycle-based logic simulation. The acceleration techniques include parallel pattern logic evaluation, circuit size reduction, and the partition of feedback loops in sequential circuits. Among all, the circuit size reduction plays a critical role in maximizing logic simulation speedup by reducing 50% of entire circuit nodes on the average. These techniques are incorporated into a levelized table-driven logic simulation system rather than a compiled-code simulation algorithm. Finally, experimental results are given to demonstrate the effectiveness of the proposed acceleration techniques. Experimental results show more than 27 times performance improvement over single pattern levelized logic simulation.

• Fashion & Textile Research Journal
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• v.18 no.4
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• pp.412-423
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• 2016

This paper explores the possibility, and suggests an experimental procedure, of industrial application of traditional textile design techniques, such as hand silkprinting and natural dyeing. Theoretical and traditional background of this study is William Morris and his followers' Arts and Crafts Movement from the late 19th century to the early 20th century, which laid the philosophical as well as technical foundations of modern textile design tradition. Based on the basic understanding of the design philosophy, and starting from the design techniques of Morris and his successors, I made some experimental and systematic color plans reflecting and exploiting the physical traits and structure of jacquard woven silk material fabrics. And I applied hand silkscreen printing techniques on the jacquard silk fabrics of my own making, while testing various color combinations of natural dyes. After finishing final processing of design samples, I could get textile design products which met the criteria of my original expectation, i.e., eco-friendly and aesthetic design samples that can also be produced in automatized mass production system of contemporary textile industry. The conclusion of this experimental study is that I can expect the natural dyeing techniques, jacquard silk fabrics design techniques, silkprinting techniques, and the basic processes used in this study to be safely applied for contemporary commercial textile industry utilizing automatized silkscreen printing system and digital printing devices.

• Steel and Composite Structures
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• v.8 no.4
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• pp.329-342
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• 2008

The strengthening of reinforced concrete (RC) columns by steel angles and strips (steel cage) is one of various techniques available to increase ultimate column load. Different authors have shown the influence of the beam-column joint on the behaviour of columns strengthened by steel cages. This paper presents an experimental study carried out at the Universidad Polit$\acute{e}$cnica de Valencia with the aim of analysing two different techniques to solve the strengthening close to the joint and the influence on the behaviour of RC columns strengthened steel cages. The ultimate loads obtained in the laboratory tests for these two techniques are compared to that specified by Eurocode 4.

• Journal of the Korean Statistical Society
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• v.5 no.1
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• pp.29-34
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• 1976

The techniques about the analysis of variance for quantitative variables have been well-developed. But when the variable is categorical, we must switch to a completely different set of varied techniques. R.J. Light and B.H. Margolin presented one kind of techniques for categorical data in their paper, where there are G unordered experimental groups and I unordered response categories.

• Journal of the Korean Society for Library and Information Science
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• v.9
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• pp.99-118
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• 1982

This paper first reviews various techniques proposed for automatic indexing with special emphasis placed on statistical techniques. Frequency-based statistical techniques are categorized into the following three approaches for further investigation on the basis of index term selection criteria: term frequency approach, document frequency approach, and probabilistic approach. In the experimental part of this study, Pao's technique based on the Goffman's transition region formula and Harter's 2-Poisson distribution model with a measure of the potential effectiveness of index term were tested. Experimental document collection consists of 30 agriculture-related documents written in Korean. Pao's technique did not yield good result presumably due to the difference in word usage between Korean and English. However, Harter's model holds some promise for Korean document indexing because the evaluation result from this experiment was similar to that of the Harter's.